1 /*
2 *class++
3 *  Name:
4 *     CmpMap
5 
6 *  Purpose:
7 *     Compound Mapping.
8 
9 *  Constructor Function:
10 c     astCmpMap
11 f     AST_CMPMAP
12 
13 *  Description:
14 *     A CmpMap is a compound Mapping which allows two component
15 *     Mappings (of any class) to be connected together to form a more
16 *     complex Mapping. This connection may either be "in series"
17 *     (where the first Mapping is used to transform the coordinates of
18 *     each point and the second mapping is then applied to the
19 *     result), or "in parallel" (where one Mapping transforms the
20 *     earlier coordinates for each point and the second Mapping
21 *     simultaneously transforms the later coordinates).
22 *
23 *     Since a CmpMap is itself a Mapping, it can be used as a
24 *     component in forming further CmpMaps. Mappings of arbitrary
25 *     complexity may be built from simple individual Mappings in this
26 *     way.
27 
28 *  Inheritance:
29 *     The CmpMap class inherits from the Mapping class.
30 
31 *  Attributes:
32 *     The CmpMap class does not define any new attributes beyond those
33 *     which are applicable to all Mappings.
34 
35 *  Functions:
36 c     The CmpMap class does not define any new functions beyond those
37 f     The CmpMap class does not define any new routines beyond those
38 *     which are applicable to all Mappings.
39 
40 *  Copyright:
41 *     Copyright (C) 1997-2006 Council for the Central Laboratory of the
42 *     Research Councils
43 
44 *  Licence:
45 *     This program is free software: you can redistribute it and/or
46 *     modify it under the terms of the GNU Lesser General Public
47 *     License as published by the Free Software Foundation, either
48 *     version 3 of the License, or (at your option) any later
49 *     version.
50 *
51 *     This program is distributed in the hope that it will be useful,
52 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
53 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
54 *     GNU Lesser General Public License for more details.
55 *
56 *     You should have received a copy of the GNU Lesser General
57 *     License along with this program.  If not, see
58 *     <http://www.gnu.org/licenses/>.
59 
60 *  Authors:
61 *     RFWS: R.F. Warren-Smith (Starlink)
62 
63 *  History:
64 *     1-FEB-1996 (RFWS):
65 *        Original version.
66 *     25-SEP-1996 (RFWS):
67 *        Implemented external interface and I/O facilities.
68 *     12-DEC-1996 (RFWS):
69 *        Over-ride the astMapList method.
70 *     13-DEC-1996 (RFWS):
71 *        Over-ride the astSimplify method.
72 *     4-JUN-1997 (RFWS):
73 *        Eliminate any simplification when MapList is used. Instead,
74 *        over-ride the MapMerge method and implement all
75 *        simplification in this.
76 *     24-MAR-1998 (RFWS):
77 *        Fixed bug in testing of simplified invert flag in Simplify.
78 *     15-APR-1998 (RFWS):
79 *        Improved the MapMerge method to allow parallel combinations
80 *        of series CmpMaps to be replaced by series combinations of
81 *        parallel CmpMaps, and vice versa.
82 *     26-SEP-2001 (DSB):
83 *        Over-ride the astDecompose method.
84 *     8-JAN-2003 (DSB):
85 *        - Changed private InitVtab method to protected astInitCmpMapVtab
86 *        method.
87 *     8-JAN-2003 (DSB):
88 *        - Modified MapMerge so that a parallel CmpMap can swap with a
89 *        suitable PermMap lower neighbour.
90 *     23-APR-2004 (DSB):
91 *        - Modified Simplify to avoid infinite loops.
92 *     27-APR-2004 (DSB):
93 *        - Correction to MapMerge to prevent segvio if CmpMap and PermMap
94 *        cannot be swapped.
95 *     4-OCT-2004 (DSB):
96 *        Modify astMapList to return flag indicating presence of inverted
97 *        CmpMaps in supplied Mapping.
98 *     20-APR-2005 (DSB):
99 *        Modify MapMerge so that it will attempt to merge the first
100 *        and second CmpMaps in a list of series CmpMaps.
101 *     8-FEB-2006 (DSB):
102 *        Corrected logic within MapMerge for cases where a PermMap is
103 *        followed by a parallel CmpMap.
104 *     14-FEB-2006 (DSB):
105 *        Override astGetObjSize.
106 *     14-MAR-2006 (DSB):
107 *        - When checking for patterns in the simplification process,
108 *        require at least 30 samples in the waveform for evidence of a
109 *        pattern.
110 *        - Override astEqual.
111 *        - The constructor no longer reports an error if the resulting
112 *	 CmpMap cannot transform points in either direction. This is
113 *	 because it may be possible to simplify such a CmpMap and the
114 *	 simplified Mapping may have defined transformations. E.g. if a
115 *	 Mapping which has only a forward transformation is combined in
116 *	 series with its own inverse, the combination will simplify to a
117 *	 UnitMap (usually).
118 *     9-MAY-2006 (DSB):
119 *        - In Simplify, remove checks for patterns in the number of atomic
120 *        mappings when calling astSimplify recursively.
121 *     23-AUG-2006 (DSB):
122 *        - In Simplify, add checks for re-appearance of a Mapping that is
123 *        already being simplified at a higher levelin the call stack.
124 *     18-APR-2007 (DSB):
125 *        In Simplify: if the returned Mapping is not a CmpMap, always copy
126 *        the returned component Mapping (rather than cloning it) so that
127 *        the returned Mapping is not affected if user code subsequently
128 *        inverts the component Mapping via some other pointer.
129 *     12-MAR-2008 (DSB):
130 *        Modify MapSplit so that attempts to split the inverse
131 *        transformation if it cannot split the forward transformation.
132 *     30-JUL-2009 (DSB):
133 *        Ensure the PermMap has equal number of inputs and outputs when
134 *        swapping a PermMap and a CmpMap in astMapMerge.
135 *     3-JAN-2011 (DSB):
136 *        In MapSplit, certain classes of Mapping (e.g. PermMaps) can
137 *        produce a returned Mapping with zero outputs. Consider such
138 *        Mappings to be unsplitable.
139 *     11-JAN-2011 (DSB):
140 *        Improve simplification of serial combinations of parellel CmpMaps.
141 *     25-JAN-2011 (DSB):
142 *        Big improvement to the efficiency of the astMapSplit method.
143 *     24-JAN-2012 (DSB):
144 *        If efficient MapSplit fails to split (e.g. due to the presence
145 *        of PermMaps), then revert to the older slower method.
146 *     5-FEB-2013 (DSB):
147 *        Take account of Invert flags when combining parallel CmpMaps in
148 *        series.
149 *     29-APR-2013 (DSB):
150 *        In MapList, use the astDoNotSimplify method to check that it is
151 *        OK to expand the CmpMap.
152 *class--
153 */
154 
155 /* Module Macros. */
156 /* ============== */
157 /* Set the name of the class we are implementing. This indicates to
158    the header files that define class interfaces that they should make
159    "protected" symbols available. */
160 #define astCLASS CmpMap
161 
162 /* Include files. */
163 /* ============== */
164 /* Interface definitions. */
165 /* ---------------------- */
166 
167 #include "error.h"               /* Error reporting facilities */
168 #include "memory.h"              /* Memory allocation facilities */
169 #include "object.h"              /* Base Object class */
170 #include "pointset.h"            /* Sets of points/coordinates */
171 #include "mapping.h"             /* Coordinate Mappings (parent class) */
172 #include "channel.h"             /* I/O channels */
173 #include "permmap.h"             /* Coordinate permutation Mappings */
174 #include "unitmap.h"             /* Unit transformations */
175 #include "cmpmap.h"              /* Interface definition for this class */
176 #include "frameset.h"            /* Interface definition for FrameSets */
177 #include "globals.h"             /* Thread-safe global data access */
178 
179 /* Error code definitions. */
180 /* ----------------------- */
181 #include "ast_err.h"             /* AST error codes */
182 
183 /* C header files. */
184 /* --------------- */
185 #include <stdarg.h>
186 #include <stddef.h>
187 #include <string.h>
188 #include <stdio.h>
189 
190 /* Module Variables. */
191 /* ================= */
192 
193 /* Address of this static variable is used as a unique identifier for
194    member of this class. */
195 static int class_check;
196 
197 /* Pointers to parent class methods which are extended by this class. */
198 static int (* parent_getobjsize)( AstObject *, int * );
199 static AstPointSet *(* parent_transform)( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
200 static int (* parent_maplist)( AstMapping *, int, int, int *, AstMapping ***, int **, int * );
201 static int *(* parent_mapsplit)( AstMapping *, int, const int *, AstMapping **, int * );
202 
203 #if defined(THREAD_SAFE)
204 static int (* parent_managelock)( AstObject *, int, int, AstObject **, int * );
205 #endif
206 
207 
208 /* Define macros for accessing each item of thread specific global data. */
209 #ifdef THREAD_SAFE
210 
211 /* Define how to initialise thread-specific globals. */
212 #define GLOBAL_inits \
213    globals->Class_Init = 0; \
214    globals->Simplify_Depth = 0; \
215    globals->Simplify_Stackmaps = NULL;
216 
217 /* Create the function that initialises global data for this module. */
218 astMAKE_INITGLOBALS(CmpMap)
219 
220 #define class_init astGLOBAL(CmpMap,Class_Init)
221 #define class_vtab astGLOBAL(CmpMap,Class_Vtab)
222 #define simplify_depth astGLOBAL(CmpMap,Simplify_Depth)
223 #define simplify_stackmaps astGLOBAL(CmpMap,Simplify_Stackmaps)
224 
225 
226 
227 /* If thread safety is not needed, declare and initialise globals at static
228    variables. */
229 #else
230 
231 static int simplify_depth  = 0;
232 static AstMapping **simplify_stackmaps = NULL;
233 
234 
235 /* Define the class virtual function table and its initialisation flag
236    as static variables. */
237 static AstCmpMapVtab class_vtab;   /* Virtual function table */
238 static int class_init = 0;       /* Virtual function table initialised? */
239 
240 #endif
241 
242 /* External Interface Function Prototypes. */
243 /* ======================================= */
244 /* The following functions have public prototypes only (i.e. no
245    protected prototypes), so we must provide local prototypes for use
246    within this module. */
247 AstCmpMap *astCmpMapId_( void *, void *, int, const char *, ... );
248 
249 /* Prototypes for Private Member Functions. */
250 /* ======================================== */
251 static AstMapping *CombineMaps( AstMapping *, int, AstMapping *, int, int, int * );
252 static AstMapping *RemoveRegions( AstMapping *, int * );
253 static AstMapping *Simplify( AstMapping *, int * );
254 static AstPointSet *Transform( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
255 static double Rate( AstMapping *, double *, int, int, int * );
256 static int *MapSplit( AstMapping *, int, const int *, AstMapping **, int * );
257 static int *MapSplit0( AstMapping *, int, const int *, AstMapping **, int, int * );
258 static int *MapSplit1( AstMapping *, int, const int *, AstMapping **, int * );
259 static int *MapSplit2( AstMapping *, int, const int *, AstMapping **, int * );
260 static int Equal( AstObject *, AstObject *, int * );
261 static int GetIsLinear( AstMapping *, int * );
262 static int MapList( AstMapping *, int, int, int *, AstMapping ***, int **, int * );
263 static int MapMerge( AstMapping *, int, int, int *, AstMapping ***, int **, int * );
264 static int PatternCheck( int, int, int **, int *, int * );
265 static void Copy( const AstObject *, AstObject *, int * );
266 static void Decompose( AstMapping *, AstMapping **, AstMapping **, int *, int *, int *, int * );
267 static void Delete( AstObject *, int * );
268 static void Dump( AstObject *, AstChannel *, int * );
269 static int GetObjSize( AstObject *, int * );
270 
271 #if defined(THREAD_SAFE)
272 static int ManageLock( AstObject *, int, int, AstObject **, int * );
273 #endif
274 
275 
276 /* Member functions. */
277 /* ================= */
Equal(AstObject * this_object,AstObject * that_object,int * status)278 static int Equal( AstObject *this_object, AstObject *that_object, int *status ) {
279 /*
280 *  Name:
281 *     Equal
282 
283 *  Purpose:
284 *     Test if two CmpMaps are equivalent.
285 
286 *  Type:
287 *     Private function.
288 
289 *  Synopsis:
290 *     #include "cmpmap.h"
291 *     int Equal( AstObject *this, AstObject *that, int *status )
292 
293 *  Class Membership:
294 *     CmpMap member function (over-rides the astEqual protected
295 *     method inherited from the astMapping class).
296 
297 *  Description:
298 *     This function returns a boolean result (0 or 1) to indicate whether
299 *     two CmpMaps are equivalent.
300 
301 *  Parameters:
302 *     this
303 *        Pointer to the first Object (a CmpMap).
304 *     that
305 *        Pointer to the second Object.
306 *     status
307 *        Pointer to the inherited status variable.
308 
309 *  Returned Value:
310 *     One if the CmpMaps are equivalent, zero otherwise.
311 
312 *  Notes:
313 *     - A value of zero will be returned if this function is invoked
314 *     with the global status set, or if it should fail for any reason.
315 */
316 
317 /* Local Variables: */
318    AstCmpMap *that;
319    AstCmpMap *this;
320    AstMapping **that_map_list;
321    AstMapping **this_map_list;
322    int *that_invert_list;
323    int *this_invert_list;
324    int i;
325    int result;
326    int that_inv;
327    int that_nmap;
328    int this_inv;
329    int this_nmap;
330 
331 /* Initialise. */
332    result = 0;
333 
334 /* Check the global error status. */
335    if ( !astOK ) return result;
336 
337 /* Obtain pointers to the two CmpMap structures. */
338    this = (AstCmpMap *) this_object;
339    that = (AstCmpMap *) that_object;
340 
341 /* Check the second object is a CmpMap. We know the first is a
342    CmpMap since we have arrived at this implementation of the virtual
343    function. */
344    if( astIsACmpMap( that ) ) {
345 
346 /* Check they are both either parallel or series. */
347       if( that->series == that->series ) {
348 
349 /* Decompose the first CmpMap into a sequence of Mappings to be applied in
350    series or parallel, as appropriate, and an associated list of
351    Invert flags. */
352          this_nmap = 0;
353          this_map_list = NULL;
354          this_invert_list = NULL;
355          astMapList( (AstMapping *) this, this->series, astGetInvert( this ),
356                      &this_nmap, &this_map_list, &this_invert_list );
357 
358 /* Similarly decompose the second CmpMap. */
359          that_nmap = 0;
360          that_map_list = NULL;
361          that_invert_list = NULL;
362          astMapList( (AstMapping *) that, that->series, astGetInvert( that ),
363                      &that_nmap, &that_map_list, &that_invert_list );
364 
365 /* Check the decompositions yielded the same number of component
366    Mappings. */
367          if( that_nmap == this_nmap ) {
368 
369 /* Check equality of every component. */
370             for( i = 0; i < this_nmap; i++ ) {
371 
372 /* Temporarily set the Mapping Invert flags to the required values,
373    saving the original values so that they can be re-instated later.*/
374                this_inv = astGetInvert( this_map_list[ i ] );
375                astSetInvert( this_map_list[ i ], this_invert_list[ i ] );
376                that_inv = astGetInvert( that_map_list[ i ] );
377                astSetInvert( that_map_list[ i ], that_invert_list[ i ] );
378 
379 /* Compare the two component Mappings for equality. */
380                result = astEqual( this_map_list[ i ], that_map_list[ i ] );
381 
382 /* Re-instate the original Invert flags. */
383                astSetInvert( this_map_list[ i ], this_inv );
384                astSetInvert( that_map_list[ i ], that_inv );
385 
386 /* Leave the loop if the Mappings are not equal. */
387                if( !result ) break;
388             }
389          }
390 
391 /* Free resources */
392          for( i = 0; i < this_nmap; i++ ) {
393             this_map_list[ i ] = astAnnul( this_map_list[ i ] );
394          }
395          this_map_list = astFree( this_map_list );
396          this_invert_list = astFree( this_invert_list );
397 
398          for( i = 0; i < that_nmap; i++ ) {
399             that_map_list[ i ] = astAnnul( that_map_list[ i ] );
400          }
401          that_map_list = astFree( that_map_list );
402          that_invert_list = astFree( that_invert_list );
403 
404       }
405    }
406 
407 /* If an error occurred, clear the result value. */
408    if ( !astOK ) result = 0;
409 
410 /* Return the result, */
411    return result;
412 }
413 
GetIsLinear(AstMapping * this_mapping,int * status)414 static int GetIsLinear( AstMapping *this_mapping, int *status ){
415 /*
416 *  Name:
417 *     GetIsLinear
418 
419 *  Purpose:
420 *     Return the value of the IsLinear attribute for a CmpMap.
421 
422 *  Type:
423 *     Private function.
424 
425 *  Synopsis:
426 *     #include "mapping.h"
427 *     void GetIsLinear( AstMapping *this, int *status )
428 
429 *  Class Membership:
430 *     CmpMap member function (over-rides the protected astGetIsLinear
431 *     method inherited from the Mapping class).
432 
433 *  Description:
434 *     This function returns the value of the IsLinear attribute for a
435 *     Frame, which is one if both component Mappings have a value of 1
436 *     for the IsLinear attribute.
437 
438 *  Parameters:
439 *     this
440 *        Pointer to the CmpqMap.
441 *     status
442 *        Pointer to the inherited status variable.
443 */
444    AstCmpMap *this;
445    this = (AstCmpMap *) this_mapping;
446    return astGetIsLinear( this->map1 ) && astGetIsLinear( this->map2 );
447 }
448 
GetObjSize(AstObject * this_object,int * status)449 static int GetObjSize( AstObject *this_object, int *status ) {
450 /*
451 *  Name:
452 *     GetObjSize
453 
454 *  Purpose:
455 *     Return the in-memory size of an Object.
456 
457 *  Type:
458 *     Private function.
459 
460 *  Synopsis:
461 *     #include "cmpmap.h"
462 *     int GetObjSize( AstObject *this, int *status )
463 
464 *  Class Membership:
465 *     CmpMap member function (over-rides the astGetObjSize protected
466 *     method inherited from the parent class).
467 
468 *  Description:
469 *     This function returns the in-memory size of the supplied CmpMap,
470 *     in bytes.
471 
472 *  Parameters:
473 *     this
474 *        Pointer to the CmpMap.
475 *     status
476 *        Pointer to the inherited status variable.
477 
478 *  Returned Value:
479 *     The Object size, in bytes.
480 
481 *  Notes:
482 *     - A value of zero will be returned if this function is invoked
483 *     with the global status set, or if it should fail for any reason.
484 */
485 
486 /* Local Variables: */
487    AstCmpMap *this;         /* Pointer to CmpMap structure */
488    int result;                /* Result value to return */
489 
490 /* Initialise. */
491    result = 0;
492 
493 /* Check the global error status. */
494    if ( !astOK ) return result;
495 
496 /* Obtain a pointers to the CmpMap structure. */
497    this = (AstCmpMap *) this_object;
498 
499 /* Invoke the GetObjSize method inherited from the parent class, and then
500    add on any components of the class structure defined by thsi class
501    which are stored in dynamically allocated memory. */
502    result = (*parent_getobjsize)( this_object, status );
503 
504    result += astGetObjSize( this->map1 );
505    result += astGetObjSize( this->map2 );
506 
507 /* If an error occurred, clear the result value. */
508    if ( !astOK ) result = 0;
509 
510 /* Return the result, */
511    return result;
512 }
513 
CombineMaps(AstMapping * mapping1,int invert1,AstMapping * mapping2,int invert2,int series,int * status)514 static AstMapping *CombineMaps( AstMapping *mapping1, int invert1,
515                                 AstMapping *mapping2, int invert2,
516                                 int series, int *status ) {
517 /*
518 *  Name:
519 *     CombineMaps
520 
521 *  Purpose:
522 *     Combine two Mappings with specified Invert flags into a CmpMap.
523 
524 *  Type:
525 *     Private function.
526 
527 *  Synopsis:
528 *     #include "cmpmap.h"
529 *     AstMapping *CombineMaps( AstMapping *mapping1, int invert1,
530 *                              AstMapping *mapping2, int invert2,
531 *                              int series, int *status )
532 
533 *  Class Membership:
534 *     CmpMap member function.
535 
536 *  Description:
537 *     This function combines two Mappings into a CmpMap (compound
538 *     Mapping) as if their Invert flags were set to specified values
539 *     when the CmpMap is created. However, the individual Mappings are
540 *     returned with their Invert flag values unchanged from their
541 *     original state.
542 
543 *  Parameters:
544 *     mapping1
545 *        Pointer to the first Mapping.
546 *     invert1
547 *        The (boolean) Invert flag value required for the first Mapping.
548 *     mapping2
549 *        Pointer to the second Mapping.
550 *     invert2
551 *        The (boolean) Invert flag value required for the second Mapping.
552 *     series
553 *        Whether the Mappings are to be combined in series (as opposed to
554 *        in parallel).
555 *     status
556 *        Pointer to the inherited status variable.
557 
558 *  Returned Value:
559 *     A pointer to the resulting compound Mapping (a CmpMap).
560 
561 *  Notes:
562 *     - This function is a wrap-up for the astCmpMap constructor and
563 *     temporarily assigns the required Invert flag values while
564 *     creating the required CmpMap. However, it also takes account of
565 *     the possibility that the two Mapping pointers supplied may point
566 *     at the same Mapping.
567 *     - A null Object pointer (AST__NULL) will be returned if this
568 *     function is invoked with the AST error status set, or if it
569 *     should fail for any reason.
570 */
571 
572 /* Local Variables: */
573    AstMapping *map1;             /* First temporary Mapping pointer */
574    AstMapping *map2;             /* Second temporary Mapping pointer */
575    AstMapping *result;           /* Pointer to result Mapping */
576    int copy;                     /* Copy needed? */
577    int inv1;                     /* First original Invert flag value */
578    int inv2;                     /* Second original Invert flag value */
579    int set1;                     /* First Invert flag originally set? */
580    int set2;                     /* Second Invert flag originally set? */
581 
582 /* Initialise */
583    result = NULL;
584 
585 /* Check the global error status. */
586    if ( !astOK ) return result;
587 
588 /* Limit incoming values to 0 or 1. */
589    invert1 = ( invert1 != 0 );
590    invert2 = ( invert2 != 0 );
591 
592 /* Obtain the Invert flag values for each Mapping. */
593    inv1 = astGetInvert( mapping1 );
594    inv2 = astGetInvert( mapping2 );
595 
596 /* Also determine if these values are explicitly set. */
597    set1 = astTestInvert( mapping1 );
598    set2 = astTestInvert( mapping2 );
599 
600 /* If both Mappings are actually the same but we need different Invert
601    flag values to be set, then this can only be achieved by making a
602    copy. Note if this is necessary. */
603    copy = ( ( mapping1 == mapping2 ) && ( invert1 != invert2 ) );
604 
605 /* Clone the first Mapping pointer. Do likewise for the second but
606    make a copy instead if necessary. */
607    map1 = astClone( mapping1 );
608    map2 = copy ? astCopy( mapping2 ) : astClone( mapping2 );
609 
610 /* If the Invert value for the first Mapping needs changing, make the
611    change. */
612    if ( invert1 != inv1 ) {
613       if ( invert1 ) {
614          astSetInvert( map1, 1 );
615       } else {
616          astClearInvert( map1 );
617       }
618    }
619 
620 /* Similarly, change the Invert flag for the second Mapping if
621    necessary. */
622    if ( invert2 != inv2 ) {
623       if ( invert2 ) {
624          astSetInvert( map2, 1 );
625       } else {
626          astClearInvert( map2 );
627       }
628    }
629 
630 /* Combine the two Mappings into a CmpMap. */
631    result = (AstMapping *) astCmpMap( map1, map2, series, "", status );
632 
633 /* If the first Mapping's Invert value was changed, restore it to its
634    original state. */
635    if ( invert1 != inv1 ) {
636       if ( set1 ) {
637          astSetInvert( map1, inv1 );
638       } else {
639          astClearInvert( map1 );
640       }
641    }
642 
643 /* Similarly, restore the second Mapping's Invert value if
644    necessary. This step is not needed, however, if a copy was made. */
645    if ( ( invert2 != inv2 ) && !copy ) {
646       if ( set2 ) {
647          astSetInvert( map2, inv2 );
648       } else {
649          astClearInvert( map2 );
650       }
651    }
652 
653 /* Annul the temporary Mapping pointers. */
654    map1 = astAnnul( map1 );
655    map2 = astAnnul( map2 );
656 
657 /* If an error occurred, then annul the result pointer. */
658    if ( !astOK ) result = astAnnul( result );
659 
660 /* Return the result. */
661    return result;
662 }
663 
Decompose(AstMapping * this_mapping,AstMapping ** map1,AstMapping ** map2,int * series,int * invert1,int * invert2,int * status)664 static void Decompose( AstMapping *this_mapping, AstMapping **map1,
665                        AstMapping **map2, int *series, int *invert1,
666                        int *invert2, int *status ) {
667 /*
668 *
669 *  Name:
670 *     Decompose
671 
672 *  Purpose:
673 *     Decompose a Mapping into two component Mappings.
674 
675 *  Type:
676 *     Private function.
677 
678 *  Synopsis:
679 *     #include "mapping.h"
680 *     void Decompose( AstMapping *this, AstMapping **map1,
681 *                     AstMapping **map2, int *series,
682 *                     int *invert1, int *invert2, int *status )
683 
684 *  Class Membership:
685 *     CmpMap member function (over-rides the protected astDecompose
686 *     method inherited from the Mapping class).
687 
688 *  Description:
689 *     This function returns pointers to two Mappings which, when applied
690 *     either in series or parallel, are equivalent to the supplied Mapping.
691 *
692 *     Since the Frame class inherits from the Mapping class, Frames can
693 *     be considered as special types of Mappings and so this method can
694 *     be used to decompose either CmpMaps or CmpFrames.
695 
696 *  Parameters:
697 *     this
698 *        Pointer to the Mapping.
699 *     map1
700 *        Address of a location to receive a pointer to first component
701 *        Mapping.
702 *     map2
703 *        Address of a location to receive a pointer to second component
704 *        Mapping.
705 *     series
706 *        Address of a location to receive a value indicating if the
707 *        component Mappings are applied in series or parallel. A non-zero
708 *        value means that the supplied Mapping is equivalent to applying map1
709 *        followed by map2 in series. A zero value means that the supplied
710 *        Mapping is equivalent to applying map1 to the lower numbered axes
711 *        and map2 to the higher numbered axes, in parallel.
712 *     invert1
713 *        The value of the Invert attribute to be used with map1.
714 *     invert2
715 *        The value of the Invert attribute to be used with map2.
716 *     status
717 *        Pointer to the inherited status variable.
718 
719 *  Notes:
720 *     - Any changes made to the component Mappings using the returned
721 *     pointers will be reflected in the supplied Mapping.
722 
723 *-
724 */
725 
726 
727 /* Local Variables: */
728    AstCmpMap *this;              /* Pointer to CmpMap structure */
729 
730 /* Check the global error status. */
731    if ( !astOK ) return;
732 
733 /* Obtain a pointer to the CmpMap structure. */
734    this = (AstCmpMap *) this_mapping;
735 
736 /* First deal with series mappings. */
737    if( this->series ) {
738       if( series ) *series = 1;
739 
740 /* If the CmpMap has been inverted, return the Mappings in reverse
741    order with inverted Invert falgs. */
742       if( astGetInvert( this ) ) {
743          if( map1 ) *map1 = astClone( this->map2 );
744          if( map2 ) *map2 = astClone( this->map1 );
745          if( invert1 ) *invert1 = this->invert2 ? 0 : 1;
746          if( invert2 ) *invert2 = this->invert1 ? 0 : 1;
747 
748 /* If the CmpMap has not been inverted, return the Mappings in their
749    original order with their original Invert flags. */
750       } else {
751          if( map1 ) *map1 = astClone( this->map1 );
752          if( map2 ) *map2 = astClone( this->map2 );
753          if( invert1 ) *invert1 = this->invert1;
754          if( invert2 ) *invert2 = this->invert2;
755       }
756 
757 /* Now deal with parallel mappings. */
758    } else {
759       if( series ) *series = 0;
760 
761 /* The mappings are returned in their original order whether or not the
762    CmpMap has been inverted. */
763       if( map1 ) *map1 = astClone( this->map1 );
764       if( map2 ) *map2 = astClone( this->map2 );
765 
766 /* If the CmpMap has been inverted, return inverted Invert flags. */
767       if( astGetInvert( this ) ) {
768          if( invert1 ) *invert1 = this->invert1 ? 0 : 1;
769          if( invert2 ) *invert2 = this->invert2 ? 0 : 1;
770 
771 /* If the CmpMap has not been inverted, return the original Invert flags. */
772       } else {
773          if( invert1 ) *invert1 = this->invert1;
774          if( invert2 ) *invert2 = this->invert2;
775       }
776 
777    }
778 }
779 
astInitCmpMapVtab_(AstCmpMapVtab * vtab,const char * name,int * status)780 void astInitCmpMapVtab_(  AstCmpMapVtab *vtab, const char *name, int *status ) {
781 /*
782 *+
783 *  Name:
784 *     astInitCmpMapVtab
785 
786 *  Purpose:
787 *     Initialise a virtual function table for a CmpMap.
788 
789 *  Type:
790 *     Protected function.
791 
792 *  Synopsis:
793 *     #include "cmpmap.h"
794 *     void astInitCmpMapVtab( AstCmpMapVtab *vtab, const char *name )
795 
796 *  Class Membership:
797 *     CmpMap vtab initialiser.
798 
799 *  Description:
800 *     This function initialises the component of a virtual function
801 *     table which is used by the CmpMap class.
802 
803 *  Parameters:
804 *     vtab
805 *        Pointer to the virtual function table. The components used by
806 *        all ancestral classes will be initialised if they have not already
807 *        been initialised.
808 *     name
809 *        Pointer to a constant null-terminated character string which contains
810 *        the name of the class to which the virtual function table belongs (it
811 *        is this pointer value that will subsequently be returned by the Object
812 *        astClass function).
813 *-
814 */
815 
816 /* Local Variables: */
817    astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
818    AstMappingVtab *mapping;      /* Pointer to Mapping component of Vtab */
819    AstObjectVtab *object;        /* Pointer to Object component of Vtab */
820 
821 /* Check the local error status. */
822    if ( !astOK ) return;
823 
824 /* Get a pointer to the thread specific global data structure. */
825    astGET_GLOBALS(NULL);
826 
827 /* Initialize the component of the virtual function table used by the
828    parent class. */
829    astInitMappingVtab( (AstMappingVtab *) vtab, name );
830 
831 /* Store a unique "magic" value in the virtual function table. This
832    will be used (by astIsACmpMap) to determine if an object belongs to
833    this class.  We can conveniently use the address of the (static)
834    class_check variable to generate this unique value. */
835    vtab->id.check = &class_check;
836    vtab->id.parent = &(((AstMappingVtab *) vtab)->id);
837 
838 /* Initialise member function pointers. */
839 /* ------------------------------------ */
840 /* Store pointers to the member functions (implemented here) that
841    provide virtual methods for this class. */
842 
843 /* None. */
844 
845 /* Save the inherited pointers to methods that will be extended, and
846    replace them with pointers to the new member functions. */
847    object = (AstObjectVtab *) vtab;
848    mapping = (AstMappingVtab *) vtab;
849    parent_getobjsize = object->GetObjSize;
850    object->GetObjSize = GetObjSize;
851 
852 #if defined(THREAD_SAFE)
853    parent_managelock = object->ManageLock;
854    object->ManageLock = ManageLock;
855 #endif
856 
857    parent_maplist = mapping->MapList;
858    mapping->MapList = MapList;
859 
860    parent_transform = mapping->Transform;
861    mapping->Transform = Transform;
862 
863    parent_mapsplit = mapping->MapSplit;
864    mapping->MapSplit = MapSplit;
865 
866 /* Store replacement pointers for methods which will be over-ridden by
867    new member functions implemented here. */
868    object->Equal = Equal;
869    mapping->Decompose = Decompose;
870    mapping->MapMerge = MapMerge;
871    mapping->Simplify = Simplify;
872    mapping->RemoveRegions = RemoveRegions;
873    mapping->GetIsLinear = GetIsLinear;
874 
875 /* For some reason the CmpMap implementation of astRate can be immensely
876    slow for complex Mapping, so it's currently disable until such time as
877    I have time to sort it out.
878 
879    mapping->Rate = Rate;
880 */
881 
882 /* Declare the copy constructor, destructor and class dump function. */
883    astSetCopy( vtab, Copy );
884    astSetDelete( vtab, Delete );
885    astSetDump( vtab, Dump, "CmpMap", "Compound Mapping" );
886 
887 /* If we have just initialised the vtab for the current class, indicate
888    that the vtab is now initialised, and store a pointer to the class
889    identifier in the base "object" level of the vtab. */
890    if( vtab == &class_vtab ) {
891       class_init = 1;
892       astSetVtabClassIdentifier( vtab, &(vtab->id) );
893    }
894 }
895 
896 #if defined(THREAD_SAFE)
ManageLock(AstObject * this_object,int mode,int extra,AstObject ** fail,int * status)897 static int ManageLock( AstObject *this_object, int mode, int extra,
898                        AstObject **fail, int *status ) {
899 /*
900 *  Name:
901 *     ManageLock
902 
903 *  Purpose:
904 *     Manage the thread lock on an Object.
905 
906 *  Type:
907 *     Private function.
908 
909 *  Synopsis:
910 *     #include "object.h"
911 *     AstObject *ManageLock( AstObject *this, int mode, int extra,
912 *                            AstObject **fail, int *status )
913 
914 *  Class Membership:
915 *     CmpMap member function (over-rides the astManageLock protected
916 *     method inherited from the parent class).
917 
918 *  Description:
919 *     This function manages the thread lock on the supplied Object. The
920 *     lock can be locked, unlocked or checked by this function as
921 *     deteremined by parameter "mode". See astLock for details of the way
922 *     these locks are used.
923 
924 *  Parameters:
925 *     this
926 *        Pointer to the Object.
927 *     mode
928 *        An integer flag indicating what the function should do:
929 *
930 *        AST__LOCK: Lock the Object for exclusive use by the calling
931 *        thread. The "extra" value indicates what should be done if the
932 *        Object is already locked (wait or report an error - see astLock).
933 *
934 *        AST__UNLOCK: Unlock the Object for use by other threads.
935 *
936 *        AST__CHECKLOCK: Check that the object is locked for use by the
937 *        calling thread (report an error if not).
938 *     extra
939 *        Extra mode-specific information.
940 *     fail
941 *        If a non-zero function value is returned, a pointer to the
942 *        Object that caused the failure is returned at "*fail". This may
943 *        be "this" or it may be an Object contained within "this". Note,
944 *        the Object's reference count is not incremented, and so the
945 *        returned pointer should not be annulled. A NULL pointer is
946 *        returned if this function returns a value of zero.
947 *     status
948 *        Pointer to the inherited status variable.
949 
950 *  Returned Value:
951 *    A local status value:
952 *        0 - Success
953 *        1 - Could not lock or unlock the object because it was already
954 *            locked by another thread.
955 *        2 - Failed to lock a POSIX mutex
956 *        3 - Failed to unlock a POSIX mutex
957 *        4 - Bad "mode" value supplied.
958 
959 *  Notes:
960 *     - This function attempts to execute even if an error has already
961 *     occurred.
962 */
963 
964 /* Local Variables: */
965    AstCmpMap *this;       /* Pointer to CmpMap structure */
966    int result;            /* Returned status value */
967 
968 /* Initialise */
969    result = 0;
970 
971 /* Check the supplied pointer is not NULL. */
972    if( !this_object ) return result;
973 
974 /* Obtain a pointers to the CmpMap structure. */
975    this = (AstCmpMap *) this_object;
976 
977 /* Invoke the ManageLock method inherited from the parent class. */
978    if( !result ) result = (*parent_managelock)( this_object, mode, extra,
979                                                 fail, status );
980 
981 /* Invoke the astManageLock method on any Objects contained within
982    the supplied Object. */
983    if( !result ) result = astManageLock( this->map1, mode, extra, fail );
984    if( !result ) result = astManageLock( this->map2, mode, extra, fail );
985 
986    return result;
987 
988 }
989 #endif
990 
MapList(AstMapping * this_mapping,int series,int invert,int * nmap,AstMapping *** map_list,int ** invert_list,int * status)991 static int MapList( AstMapping *this_mapping, int series, int invert,
992                      int *nmap, AstMapping ***map_list, int **invert_list, int *status ) {
993 /*
994 *  Name:
995 *     MapList
996 
997 *  Purpose:
998 *     Decompose a CmpMap into a sequence of simpler Mappings.
999 
1000 *  Type:
1001 *     Private function.
1002 
1003 *  Synopsis:
1004 *     #include "mapping.h"
1005 *     int MapList( AstMapping *this, int series, int invert, int *nmap,
1006 *                  AstMapping ***map_list, int **invert_list )
1007 
1008 *  Class Membership:
1009 *     CmpMap member function (over-rides the protected astMapList
1010 *     method inherited from the Maping class).
1011 
1012 *  Description:
1013 *     This function decomposes a CmpMap into a sequence of simpler
1014 *     Mappings which may be applied in sequence to achieve the same
1015 *     effect. The CmpMap is decomposed as far as possible, but it is
1016 *     not guaranteed that this will necessarily yield any more than
1017 *     one Mapping, which may actually be the original CmpMap supplied.
1018 *
1019 *     This function is provided to support both the simplification of
1020 *     CmpMaps, and the analysis of CmpMap structure so that particular
1021 *     forms can be recognised.
1022 
1023 *  Parameters:
1024 *     this
1025 *        Pointer to the CmpMap to be decomposed (the CmpMap is not
1026 *        actually modified by this function).
1027 *     series
1028 *        If this value is non-zero, an attempt will be made to
1029 *        decompose the CmpMap into a sequence of equivalent Mappings
1030 *        which can be applied in series (i.e. one after the other). If
1031 *        it is zero, the decomposition will instead yield Mappings
1032 *        which can be applied in parallel (i.e. on successive sub-sets
1033 *        of the input/output coordinates).
1034 *     invert
1035 *        The value to which the CmpMap's Invert attribute is to be
1036 *        (notionally) set before performing the
1037 *        decomposition. Normally, the value supplied here will be the
1038 *        actual Invert value obtained from the CmpMap (e.g. using
1039 *        astGetInvert).  Sometimes, however, when a CmpMap is
1040 *        encapsulated within another structure, that structure may
1041 *        retain an Invert value (in order to prevent external
1042 *        interference) which should be used instead.
1043 *
1044 *        Note that the actual Invert value of the CmpMap supplied is
1045 *        not used (or modified) by this function.
1046 *     nmap
1047 *        The address of an int which holds a count of the number of
1048 *        individual Mappings in the decomposition. On entry, this
1049 *        should count the number of Mappings already in the
1050 *        "*map_list" array (below). On exit, it is updated to include
1051 *        any new Mappings appended by this function.
1052 *     map_list
1053 *        Address of a pointer to an array of Mapping pointers. On
1054 *        entry, this array pointer should either be NULL (if no
1055 *        Mappings have yet been obtained) or should point at a
1056 *        dynamically allocated array containing Mapping pointers
1057 *        ("*nmap" in number) which have been obtained from a previous
1058 *        invocation of this function.
1059 *
1060 *        On exit, the dynamic array will be enlarged to contain any
1061 *        new Mapping pointers that result from the decomposition
1062 *        requested. These pointers will be appended to any previously
1063 *        present, and the array pointer will be updated as necessary
1064 *        to refer to the enlarged array (any space released by the
1065 *        original array will be freed automatically).
1066 *
1067 *        The new Mapping pointers returned will identify a sequence of
1068 *        Mappings which, when applied in order, will perform a forward
1069 *        transformation equivalent to that of the original CmpMap
1070 *        (after its Invert flag has first been set to the value
1071 *        requested above). The Mappings should be applied in series or
1072 *        in parallel according to the type of decomposition requested.
1073 *
1074 *        All the Mapping pointers returned by this function should be
1075 *        annulled by the caller, using astAnnul, when no longer
1076 *        required. The dynamic array holding these pointers should
1077 *        also be freed, using astFree.
1078 *     invert_list
1079 *        Address of a pointer to an array of int. On entry, this array
1080 *        pointer should either be NULL (if no Mappings have yet been
1081 *        obtained) or should point at a dynamically allocated array
1082 *        containing Invert attribute values ("*nmap" in number) which
1083 *        have been obtained from a previous invocation of this
1084 *        function.
1085 *
1086 *        On exit, the dynamic array will be enlarged to contain any
1087 *        new Invert attribute values that result from the
1088 *        decomposition requested. These values will be appended to any
1089 *        previously present, and the array pointer will be updated as
1090 *        necessary to refer to the enlarged array (any space released
1091 *        by the original array will be freed automatically).
1092 *
1093 *        The new Invert values returned identify the values which must
1094 *        be assigned to the Invert attributes of the corresponding
1095 *        Mappings (whose pointers are in the "*map_list" array) before
1096 *        they are applied. Note that these values may differ from the
1097 *        actual Invert attribute values of these Mappings, which are
1098 *        not relevant.
1099 *
1100 *        The dynamic array holding these values should be freed by the
1101 *        caller, using astFree, when no longer required.
1102 
1103 *  Returned Value:
1104 *     A non-zero value is returned if the supplied Mapping contained any
1105 *     inverted CmpMaps.
1106 
1107 *  Notes:
1108 *     - It is unspecified to what extent the original CmpMap and the
1109 *     individual (decomposed) Mappings are
1110 *     inter-dependent. Consequently, the individual Mappings cannot be
1111 *     modified without risking modification of the original CmpMap.
1112 *     - If this function is invoked with the global error status set,
1113 *     or if it should fail for any reason, then the *nmap value, the
1114 *     list of Mapping pointers and the list of Invert values will all
1115 *     be returned unchanged.
1116 */
1117 
1118 /* Local Variables: */
1119    AstCmpMap *this;              /* Pointer to CmpMap structure */
1120    int invert1;                  /* Invert flag for first component Mapping */
1121    int invert2;                  /* Invert flag for second component Mapping */
1122    int r1;                       /* Value returned from first map list */
1123    int r2;                       /* Value returned from second map list */
1124    int result;                   /* Returned value */
1125 
1126 /* Check the global error status. */
1127    if ( !astOK ) return 0;
1128 
1129 /* Obtain a pointer to the CmpMap structure. */
1130    this = (AstCmpMap *) this_mapping;
1131 
1132 /* Check if the CmpMap combines its component Mappings in the same way
1133    (series or parallel) as the decomposition requires. Also, do not
1134    expand CmpMaps that are not appropriate for simplification. */
1135    if ( this->series == series && !astDoNotSimplify( this ) ) {
1136 
1137 /* If so, obtain the Invert attribute values to be applied to each
1138    component Mapping. */
1139       invert1 = this->invert1;
1140       invert2 = this->invert2;
1141 
1142 /* If the CmpMap itself is inverted, also invert the Invert values to be
1143    applied to its components. */
1144       if ( invert ) {
1145          invert1 = !invert1;
1146          invert2 = !invert2;
1147       }
1148 
1149 /* If the component Mappings are applied in series, then concatenate
1150    the Mapping lists obtained from each of them. Do this in reverse
1151    order if the CmpMap is inverted, since the second Mapping would be
1152    applied first in this case. */
1153       if ( series ) {
1154          if ( !invert ) {
1155             r1 = astMapList( this->map1, series, invert1,
1156                              nmap, map_list, invert_list );
1157             r2 = astMapList( this->map2, series, invert2,
1158                              nmap, map_list, invert_list );
1159          } else {
1160             r1 = astMapList( this->map2, series, invert2,
1161                              nmap, map_list, invert_list );
1162             r2 = astMapList( this->map1, series, invert1,
1163                              nmap, map_list, invert_list );
1164          }
1165 
1166 /* If the component Mappings are applied in parallel, then concatenate
1167    the Mapping lists obtained from each of them. In this case,
1168    inverting the CmpMap has no effect on the order in which they are
1169    applied. */
1170       } else {
1171          r1 = astMapList( this->map1, series, invert1,
1172                           nmap, map_list, invert_list );
1173          r2 = astMapList( this->map2, series, invert2,
1174                           nmap, map_list, invert_list );
1175       }
1176 
1177 /* Did we find any inverted CmpMaps? */
1178       result = invert || r1 || r2;
1179 
1180 /* If the CmpMap does not combine its components in the way required
1181    by the decomposition (series or parallel), then we cannot decompose
1182    it. In this case it must be appended to the Mapping list as a
1183    single entity. We can use the parent class method to do this. */
1184    } else {
1185       result = ( *parent_maplist )( this_mapping, series, invert, nmap,
1186                                     map_list, invert_list, status );
1187    }
1188 
1189    return result;
1190 }
1191 
MapMerge(AstMapping * this,int where,int series,int * nmap,AstMapping *** map_list,int ** invert_list,int * status)1192 static int MapMerge( AstMapping *this, int where, int series, int *nmap,
1193                      AstMapping ***map_list, int **invert_list, int *status ) {
1194 /*
1195 *  Name:
1196 *     MapMerge
1197 
1198 *  Purpose:
1199 *     Simplify a sequence of Mappings containing a CmpMap.
1200 
1201 *  Type:
1202 *     Private function.
1203 
1204 *  Synopsis:
1205 *     #include "mapping.h"
1206 *     int MapMerge( AstMapping *this, int where, int series, int *nmap,
1207 *                   AstMapping ***map_list, int **invert_list )
1208 
1209 *  Class Membership:
1210 *     CmpMap method (over-rides the protected astMapMerge method
1211 *     inherited from the Mapping class).
1212 
1213 *  Description:
1214 *     This function attempts to simplify a sequence of Mappings by
1215 *     merging a nominated CmpMap in the sequence with its neighbours,
1216 *     so as to shorten the sequence if possible.
1217 *
1218 *     In many cases, simplification will not be possible and the
1219 *     function will return -1 to indicate this, without further
1220 *     action.
1221 *
1222 *     In most cases of interest, however, this function will either
1223 *     attempt to replace the nominated CmpMap with one which it
1224 *     considers simpler, or to merge it with the Mappings which
1225 *     immediately precede it or follow it in the sequence (both will
1226 *     normally be considered). This is sufficient to ensure the
1227 *     eventual simplification of most Mapping sequences by repeated
1228 *     application of this function.
1229 *
1230 *     In some cases, the function may attempt more elaborate
1231 *     simplification, involving any number of other Mappings in the
1232 *     sequence. It is not restricted in the type or scope of
1233 *     simplification it may perform, but will normally only attempt
1234 *     elaborate simplification in cases where a more straightforward
1235 *     approach is not adequate.
1236 
1237 *  Parameters:
1238 *     this
1239 *        Pointer to the nominated CmpMap which is to be merged with
1240 *        its neighbours. This should be a cloned copy of the CmpMap
1241 *        pointer contained in the array element "(*map_list)[where]"
1242 *        (see below). This pointer will not be annulled, and the
1243 *        CmpMap it identifies will not be modified by this function.
1244 *     where
1245 *        Index in the "*map_list" array (below) at which the pointer
1246 *        to the nominated CmpMap resides.
1247 *     series
1248 *        A non-zero value indicates that the sequence of Mappings to
1249 *        be simplified will be applied in series (i.e. one after the
1250 *        other), whereas a zero value indicates that they will be
1251 *        applied in parallel (i.e. on successive sub-sets of the
1252 *        input/output coordinates).
1253 *     nmap
1254 *        Address of an int which counts the number of Mappings in the
1255 *        sequence. On entry this should be set to the initial number
1256 *        of Mappings. On exit it will be updated to record the number
1257 *        of Mappings remaining after simplification.
1258 *     map_list
1259 *        Address of a pointer to a dynamically allocated array of
1260 *        Mapping pointers (produced, for example, by the astMapList
1261 *        method) which identifies the sequence of Mappings. On entry,
1262 *        the initial sequence of Mappings to be simplified should be
1263 *        supplied.
1264 *
1265 *        On exit, the contents of this array will be modified to
1266 *        reflect any simplification carried out. Any form of
1267 *        simplification may be performed. This may involve any of: (a)
1268 *        removing Mappings by annulling any of the pointers supplied,
1269 *        (b) replacing them with pointers to new Mappings, (c)
1270 *        inserting additional Mappings and (d) changing their order.
1271 *
1272 *        The intention is to reduce the number of Mappings in the
1273 *        sequence, if possible, and any reduction will be reflected in
1274 *        the value of "*nmap" returned. However, simplifications which
1275 *        do not reduce the length of the sequence (but improve its
1276 *        execution time, for example) may also be performed, and the
1277 *        sequence might conceivably increase in length (but normally
1278 *        only in order to split up a Mapping into pieces that can be
1279 *        more easily merged with their neighbours on subsequent
1280 *        invocations of this function).
1281 *
1282 *        If Mappings are removed from the sequence, any gaps that
1283 *        remain will be closed up, by moving subsequent Mapping
1284 *        pointers along in the array, so that vacated elements occur
1285 *        at the end. If the sequence increases in length, the array
1286 *        will be extended (and its pointer updated) if necessary to
1287 *        accommodate any new elements.
1288 *
1289 *        Note that any (or all) of the Mapping pointers supplied in
1290 *        this array may be annulled by this function, but the Mappings
1291 *        to which they refer are not modified in any way (although
1292 *        they may, of course, be deleted if the annulled pointer is
1293 *        the final one).
1294 *     invert_list
1295 *        Address of a pointer to a dynamically allocated array which,
1296 *        on entry, should contain values to be assigned to the Invert
1297 *        attributes of the Mappings identified in the "*map_list"
1298 *        array before they are applied (this array might have been
1299 *        produced, for example, by the astMapList method). These
1300 *        values will be used by this function instead of the actual
1301 *        Invert attributes of the Mappings supplied, which are
1302 *        ignored.
1303 *
1304 *        On exit, the contents of this array will be updated to
1305 *        correspond with the possibly modified contents of the
1306 *        "*map_list" array.  If the Mapping sequence increases in
1307 *        length, the "*invert_list" array will be extended (and its
1308 *        pointer updated) if necessary to accommodate any new
1309 *        elements.
1310 
1311 *  Returned Value:
1312 *     If simplification was possible, the function returns the index
1313 *     in the "map_list" array of the first element which was
1314 *     modified. Otherwise, it returns -1 (and makes no changes to the
1315 *     arrays supplied).
1316 
1317 *  Notes:
1318 *     - A value of -1 will be returned if this function is invoked
1319 *     with the global error status set, or if it should fail for any
1320 *     reason.
1321 */
1322 
1323 /* Local Variables: */
1324    AstCmpMap *cmpmap1;           /* Pointer to first CmpMap */
1325    AstCmpMap *cmpmap2;           /* Pointer to second CmpMap */
1326    AstCmpMap *cmpmap;            /* Pointer to nominated CmpMap */
1327    AstCmpMap *new_cm;            /* Pointer to new CmpMap */
1328    AstMapping **map_list1;       /* Pointer to list of cmpmap1 component Mappings */
1329    AstMapping **map_list2;       /* Pointer to list of cmpmap2 component Mappings */
1330    AstMapping **new_map_list;    /* Extended Mapping list */
1331    AstMapping *map;              /* Pointer to nominated CmpMap */
1332    AstMapping *new1;             /* Pointer to new CmpMap */
1333    AstMapping *new2;             /* Pointer to new CmpMap */
1334    AstMapping *new;              /* Pointer to replacement Mapping */
1335    AstMapping *simp1;            /* Pointer to simplified Mapping */
1336    AstMapping *simp2;            /* Pointer to simplified Mapping */
1337    AstMapping *submap1;          /* A subset of mappings from cmpmap1 */
1338    AstMapping *submap2;          /* A subset of mappings from cmpmap2 */
1339    AstMapping *tmap2;            /* Temporary Mapping */
1340    AstMapping *tmap;             /* Temporary Mapping */
1341    AstPermMap *new_pm;           /* Pointer to new PermMap */
1342    AstPermMap *permmap1;         /* Pointer to first PermMap */
1343    AstUnitMap *unit;             /* UnitMap that feeds const PermMap i/p's */
1344    const char *class;            /* Pointer to Mapping class string */
1345    double *conperm;              /* Pointer to PermMap constants array */
1346    double *const_new;            /* Pointer to new PermMap constants array */
1347    double *p;                    /* Pointer to PermMap input position */
1348    double *q;                    /* Pointer to PermMap output position */
1349    double *qa;                   /* Pointer to 1st component output position */
1350    double *qb;                   /* Pointer to 2nd component output position */
1351    int *inperm;                  /* Pointer to copy of PermMap inperm array */
1352    int *inperm_new;              /* Pointer to new PermMap inperm array */
1353    int *invert_list1;            /* Pointer to list of cmpmap1 invert values */
1354    int *invert_list2;            /* Pointer to list of cmpmap2 invert values */
1355    int *new_invert_list;         /* Extended Invert flag list */
1356    int *outperm;                 /* Pointer to copy of PermMap outperm array */
1357    int *outperm_new;             /* Pointer to new PermMap outperm array */
1358    int aconstants;               /* Are all 1st component outputs constant? */
1359    int bconstants;               /* Are all 2nd component outputs constant? */
1360    int canswap;                  /* Can nominated Mapping swap with lower neighbour? */
1361    int i;                        /* Coordinate index */
1362    int iconid;                   /* Constant identifier in supplied PermMap */
1363    int imap1;                    /* Index of first Mapping */
1364    int imap2;                    /* Index of second Mapping */
1365    int imap;                     /* Loop counter for Mappings */
1366    int invert1;                  /* Invert flag for first CmpMap */
1367    int invert1a;                 /* Invert flag for sub-Mapping */
1368    int invert1b;                 /* Invert flag for sub-Mapping */
1369    int invert2;                  /* Invert flag for second CmpMap */
1370    int invert2a;                 /* Invert flag for sub-Mapping */
1371    int invert2b;                 /* Invert flag for sub-Mapping */
1372    int invert;                   /* Invert attribute value */
1373    int j;                        /* Coordinate index */
1374    int jmap1;                    /* Index of next component Mapping in cmpmap1 */
1375    int jmap2;                    /* Index of next component Mapping in cmpmap2 */
1376    int new_invert;               /* New Invert attribute value */
1377    int nin2a;                    /* No. input coordinates for sub-Mapping */
1378    int nin2b;                    /* No. input coordinates for sub-Mapping */
1379    int nmap1;                    /* Number of Mappings in cmpmap1 */
1380    int nmap2;                    /* Number of Mappings in cmpmap2 */
1381    int nout2a;                   /* No. of outputs for 1st component Mapping */
1382    int nout2b;                   /* No. of outputs for 2nd component Mapping */
1383    int npin;                     /* No. of inputs for original PermMap */
1384    int npin_new;                 /* No. of inputs for new PermMap */
1385    int npout;                    /* No. of outputs for original PermMap */
1386    int npout_new;                /* No. of outputs for new PermMap */
1387    int nunit;                    /* No. of PermMap i/p's fed by UnitMap */
1388    int oconid;                   /* Constant identifier in returned PermMap */
1389    int result;                   /* Result value to return */
1390    int set;                      /* Invert attribute set? */
1391    int simpler;                  /* Simplification possible? */
1392    int subin2;                   /* Number of inputs of submap2 */
1393    int subinv1;                  /* Invert attribute to use with submap1 */
1394    int subinv2;                  /* Invert attribute to use with submap2 */
1395    int subout1;                  /* Number of outputs of submap1 */
1396 
1397 /* Initialise.*/
1398    result = -1;
1399 
1400 /* Check the inherited status. */
1401    if ( !astOK ) return result;
1402 
1403 /* Simplify the CmpMap on its own. */
1404 /* =============================== */
1405 /* Obtain a pointer to the nominated Mapping (which is a CmpMap). */
1406    map = ( *map_list )[ where ];
1407    cmpmap = (AstCmpMap *) map;
1408 
1409 /* Determine if the Mapping's Invert attribute is set and obtain its
1410    value. */
1411    set = astTestInvert( map );
1412    invert = astGetInvert( map );
1413 
1414 /* If necessary, change the Invert attribute to the value we want. We
1415    do this so that simplification (below) has a chance to absorb a
1416    non-zero Invert value into the implementation of the simplified
1417    Mapping (the preference being to have an Invert value of zero after
1418    simplification, if possible). */
1419    if ( invert != ( *invert_list )[ where ] ) {
1420       astSetInvert( map, ( *invert_list )[ where ] );
1421    }
1422 
1423 /* Simplify the Mapping and obtain the new Invert value. */
1424    new = astSimplify( map );
1425    new_invert = astGetInvert( new );
1426 
1427 /* If necessary, restore the original Mapping's Invert attribute to
1428    its initial state. */
1429    if ( invert != ( *invert_list )[ where ] ) {
1430       if ( set ) {
1431          astSetInvert( map, invert );
1432       } else {
1433          astClearInvert( map );
1434       }
1435    }
1436 
1437 /* We must now determine if simplification has occurred. Since this is
1438    internal code, we can compare the two Mapping pointers directly to
1439    see whether "astSimplify" just cloned the pointer we gave it. If it
1440    did, then simplification was probably not possible, but check to
1441    see if the Invert attribute has changed to be sure. */
1442    if ( astOK ) {
1443       simpler = ( new != map ) || ( new_invert != ( *invert_list )[ where ] );
1444 
1445 /* If simplification was successful, annul the original pointer in the
1446    Mapping list and replace it with the new one, together with its
1447    invert flag. */
1448       if ( simpler ) {
1449          (void) astAnnul( ( *map_list )[ where ] );
1450          ( *map_list )[ where ] = new;
1451          ( *invert_list )[ where ] = new_invert;
1452 
1453 /* Return the result. */
1454          result = where;
1455 
1456 /* Otherwise, annul the new Mapping pointer. */
1457       } else {
1458          new = astAnnul( new );
1459 
1460 /* If the nominated CmpMap is a series CmpMap and the sequence of
1461    Mappings are being combined in series, or if the nominated CmpMap is
1462    a parallel CmpMap and the sequence of Mappings are being combined in
1463    parallel, replace the single CmpMap with the two component Mappings. */
1464          if( ( series && cmpmap->series ) ||
1465              ( !series && !cmpmap->series ) ) {
1466 
1467 /* We are increasing the number of Mappings in the list, so we need to create
1468    new, larger, arrays to hold the list of Mapping pointers and invert flags. */
1469             new_map_list = astMalloc( ( *nmap + 1 )*sizeof( AstMapping * ) );
1470             new_invert_list = astMalloc( ( *nmap + 1 )*sizeof( int ) );
1471             if( astOK ) {
1472 
1473 /* Copy the values prior to the nominated CmpMap. */
1474                for( i = 0; i < where; i++ ) {
1475                   new_map_list[ i ] = astClone( ( *map_list )[ i ] );
1476                   new_invert_list[ i ] = ( *invert_list )[ i ];
1477                }
1478 
1479 /* Next insert the two components of the nominated CmpMap */
1480                new_map_list[ where ] = astClone( cmpmap->map1 );
1481                new_invert_list[ where ] = cmpmap->invert1;
1482                new_map_list[ where + 1 ] = astClone( cmpmap->map2 );
1483                new_invert_list[ where + 1 ] = cmpmap->invert2;
1484 
1485 /* Now copy any values after the nominated CmpMap. */
1486                for( i = where + 1; i < *nmap; i++ ) {
1487                   new_map_list[ i + 1 ] = astClone( ( *map_list )[ i ] );
1488                   new_invert_list[ i + 1 ] = ( *invert_list )[ i ];
1489                }
1490 
1491 /* Now annul the Object pointers in the supplied map list. */
1492                for( i = 0; i < *nmap; i++ ) {
1493                   (* map_list )[ i ] = astAnnul( ( *map_list )[ i ] );
1494                }
1495 
1496 /* Free the memory holding the supplied Mapping and invert flag lists. */
1497                astFree( *map_list );
1498                astFree( *invert_list );
1499 
1500 /* Return pointers to the new extended lists. */
1501                *map_list = new_map_list;
1502                *invert_list = new_invert_list;
1503 
1504 /* Increase the number of Mappings in the list, and the index of
1505    the first modified Mapping. */
1506                (*nmap)++;
1507                result = where;
1508 
1509 /* Indicate some simplification has taken place */
1510                simpler = 1;
1511             }
1512          }
1513       }
1514 
1515 /* If no simplification has been done, merge adjacent CmpMaps. */
1516 /* ========================================================== */
1517 /* If the CmpMap would not simplify on its own, we now look for a
1518    neighbouring CmpMap with which it might merge. We use the previous
1519    Mapping, if suitable, since this will normally also have been fully
1520    simplified on its own. Check if a previous Mapping exists. */
1521       if( !simpler ) {
1522          if ( astOK && *nmap > 1 ) {
1523 
1524 /* Obtain the indices of the two potential Mappings to be merged. imap1
1525    is the first Mapping, imap2 is the second. imapc is the CmpMap, imapn is
1526    the neighbouring Mapping. */
1527             if( where == 0 ) {
1528                imap1 = 0;
1529                imap2 = 1;
1530             } else {
1531                imap1 = where - 1;
1532                imap2 = where;
1533             }
1534 
1535 /* Obtain the Class string of the neighbouring Mapping and determine if it
1536    is a CmpMap. */
1537             class = astGetClass( ( *map_list )[ (where>0)?where-1:1 ] );
1538             if ( astOK && !strcmp( class, "CmpMap" ) ) {
1539 
1540 /* If suitable, obtain pointers to the two CmpMaps. */
1541                cmpmap1 = (AstCmpMap *) ( *map_list )[ imap1 ];
1542                cmpmap2 = (AstCmpMap *) ( *map_list )[ imap2 ];
1543 
1544 /* Obtain the associated invert flag values. */
1545                invert1 = ( *invert_list )[ imap1 ];
1546                invert2 = ( *invert_list )[ imap2 ];
1547 
1548 /* Extract the invert flags associated with each CmpMap sub-Mapping
1549    and combine these with the flag values obtained above so as to give
1550    the invert flag to be used with each individual sub-Mapping. */
1551                invert1a = cmpmap1->invert1;
1552                invert1b = cmpmap1->invert2;
1553                if ( invert1 ) {
1554                   invert1a = !invert1a;
1555                   invert1b = !invert1b;
1556                }
1557                invert2a = cmpmap2->invert1;
1558                invert2b = cmpmap2->invert2;
1559                if ( invert2 ) {
1560                   invert2a = !invert2a;
1561                   invert2b = !invert2b;
1562                }
1563 
1564 /* Series CmpMaps in parallel. */
1565 /* =========================== */
1566 /* Now check if the CmpMaps can be merged. This may be possible if we
1567    are examining a list of Mappings combined in parallel and the two
1568    adjacent CmpMaps both combine their sub-Mappings in series. */
1569                if ( !series && cmpmap1->series && cmpmap2->series ) {
1570 
1571 /* Form two new parallel CmpMaps with the sub-Mappings re-arranged so
1572    that when combined in series these new CmpMaps are equivalent to
1573    the original ones. In doing this, we must take account of the
1574    invert flags which apply to each sub-Mapping and also of the fact
1575    that the order in which the sub-Mappings are applied depends on the
1576    invert flags of the original CmpMaps. */
1577                   new1 = CombineMaps( invert1 ? cmpmap1->map2 : cmpmap1->map1,
1578                                       invert1 ? invert1b      : invert1a,
1579                                       invert2 ? cmpmap2->map2 : cmpmap2->map1,
1580                                       invert2 ? invert2b      : invert2a, 0, status );
1581                   new2 = CombineMaps( invert1 ? cmpmap1->map1 : cmpmap1->map2,
1582                                       invert1 ? invert1a      : invert1b,
1583                                       invert2 ? cmpmap2->map1 : cmpmap2->map2,
1584                                       invert2 ? invert2a      : invert2b, 0, status );
1585 
1586 /* Having converted the parallel combination of series CmpMaps into a
1587    pair of equivalent parallel CmpMaps that can be combined in series,
1588    try and simplify each of these new CmpMaps. */
1589                   simp1 = astSimplify( new1 );
1590                   simp2 = astSimplify( new2 );
1591 
1592 /* Test if either could be simplified by checking if its pointer value
1593    has changed. Also check if the Invert attribute has changed (not
1594    strictly necessary, but a useful safety feature in case of any
1595    rogue code which just changes this attribute instead of issuing a
1596    new pointer). */
1597                   simpler = ( simp1 != new1 ) || ( simp2 != new2 ) ||
1598                             astGetInvert( simp1 ) || astGetInvert( simp2 );
1599 
1600 /* If either CmpMap was simplified, then combine the resulting
1601    Mappings in series to give the replacement CmpMap. */
1602                   if ( simpler ) new =
1603                                (AstMapping *) astCmpMap( simp1, simp2, 1, "", status );
1604 
1605 /* Annul the temporary Mapping pointers. */
1606                   new1 = astAnnul( new1 );
1607                   new2 = astAnnul( new2 );
1608                   simp1 = astAnnul( simp1 );
1609                   simp2 = astAnnul( simp2 );
1610 
1611 /* Parallel CmpMaps in series. */
1612 /* =========================== */
1613 /* A pair of adjacent CmpMaps can also potentially be merged if we are
1614    examining a list of Mappings combined in series and the two
1615    adjacent CmpMaps both combine their sub-Mappings in parallel. */
1616                } else if ( series && !cmpmap1->series && !cmpmap2->series ) {
1617 
1618 /* Expand each of the two adjacent CmpMaps into a list of Mappings to be
1619    combined in parallel. */
1620                   map_list1 = map_list2 = NULL;
1621                   invert_list1 = invert_list2 = NULL;
1622                   nmap1 = nmap2 = 0;
1623                   (void) astMapList( (AstMapping *) cmpmap1, 0, invert1,
1624                                      &nmap1, &map_list1, &invert_list1 );
1625                   (void) astMapList( (AstMapping *) cmpmap2, 0, invert2,
1626                                      &nmap2, &map_list2, &invert_list2 );
1627 
1628 /* We want to divide each of these lists into N sub-lists so that the
1629    outputs of the Mappings in the i'th sub-list from cmpmap1 can feed
1630    (i.e. equal in number) the inputs of the Mappings in the i'th sub-list
1631    from cmpmap2. If such a sub-list contains more than one Mapping we
1632    combine them together into a parallel CmpMap. Initialise a flag to
1633    indicate that we have not yet found any genuine simplification. */
1634                   simpler = 0;
1635 
1636 /* Initialise the index of the next Mapping to be added into each
1637    sublist. */
1638                   jmap1 = jmap2 = 0;
1639 
1640 /* Indicate both sublists are currently empty. */
1641                   subout1 = subin2 = 0;
1642                   new = submap1 = submap2 = NULL;
1643                   subinv1 = subinv2 = 0;
1644 
1645 /* Loop round untill all Mappings have been used. */
1646                   while( jmap1 <= nmap1 && jmap2 <= nmap2 && astOK ) {
1647 
1648 /* Note the number of outputs from submap1 and the number of inputs to
1649    submap2. If the Invert flag is not set to the required value for
1650    either Mapping, then inputs become outputs and vice-versa, so swap Nin
1651    and Nout. */
1652                      if( !submap1 ) {
1653                         subout1 = 0;
1654                      } else if( subinv1 == astGetInvert( submap1 ) ) {
1655                         subout1 = astGetNout( submap1 );
1656                      } else {
1657                         subout1 = astGetNin( submap1 );
1658                      }
1659 
1660                      if( !submap2 ) {
1661                         subin2 = 0;
1662                      } else if( subinv2 == astGetInvert( submap2 ) ) {
1663                         subin2 = astGetNin( submap2 );
1664                      } else {
1665                         subin2 = astGetNout( submap2 );
1666                      }
1667 
1668 /* If sublist for cmpmap1 has too few outputs, add the next Mapping from
1669    the cmpmap1 list into the submap1 sublist. */
1670                      if( subout1 < subin2 ) {
1671                         tmap = CombineMaps( submap1, subinv1,
1672                                             map_list1[ jmap1 ],
1673                                             invert_list1[ jmap1 ], 0, status );
1674                         (void) astAnnul( submap1 );
1675                         submap1 = tmap;
1676                         subinv1 = 0;
1677                         jmap1++;
1678 
1679 /* If sublist for cmpmap2 has too few inputs, add the next Mapping from
1680    the cmpmap2 list into the submap2 sublist. */
1681                      } else if( subin2 < subout1 ) {
1682                         tmap = CombineMaps( submap2, subinv2,
1683                                             map_list2[ jmap2 ],
1684                                             invert_list2[ jmap2 ], 0, status );
1685                         (void) astAnnul( submap2 );
1686                         submap2 = tmap;
1687                         subinv2 = 0;
1688                         jmap2++;
1689 
1690 /* If submap1 can now feed submap2, combine them in series, and attempt to
1691    simplify it. */
1692                      } else {
1693 
1694 /* Check this is not the first pass (when we do not have a submap1 or
1695    submap2). */
1696                         if( submap1 && submap2 ) {
1697 
1698 /* Combine the Mappings in series and simplify. */
1699                            tmap = CombineMaps( submap1, subinv1, submap2,
1700                                                subinv2, 1, status );
1701                            submap1 = astAnnul( submap1 );
1702                            submap2 = astAnnul( submap2 );
1703                            tmap2 = astSimplify( tmap );
1704                            tmap = astAnnul( tmap );
1705 
1706 /* Note if any simplification took place. */
1707                            if( tmap != tmap2 ||
1708                                astGetInvert( tmap ) != astGetInvert( tmap2 ) )
1709                                            simpler = 1;
1710 
1711 /* Add the simplifed Mapping into the total merged Mapping (a parallel
1712    CmpMap). */
1713                            if( !new ) {
1714                               new = tmap2;
1715                            } else {
1716                               tmap = (AstMapping *) astCmpMap( new, tmap2, 0,
1717                                                                " ", status );
1718                               tmap2 = astAnnul( tmap2 );
1719                               (void) astAnnul( new );
1720                               new = tmap;
1721                            }
1722                         }
1723 
1724 /* Reset submap1 to be the next Mapping from the cmpmap1 map list. First,
1725    save its old Invert flag and set it to the required value. */
1726                         if( jmap1 < nmap1 ) {
1727                            submap1 = astClone( map_list1[ jmap1 ] );
1728                            subinv1 = invert_list1[ jmap1 ];
1729                            jmap1++;
1730                         } else {
1731                            break;
1732                         }
1733 
1734 /* Do the same for the second list. */
1735                         if( jmap2 < nmap2 ) {
1736                            submap2 = astClone( map_list2[ jmap2 ] );
1737                            subinv2 = invert_list2[ jmap2 ];
1738                            jmap2++;
1739                         } else {
1740                            break;
1741                         }
1742                      }
1743                   }
1744 
1745 /* Free the lists of Mapping pointers and invert flags. */
1746                   if( map_list1 ) {
1747                      for( jmap1 = 0; jmap1 < nmap1; jmap1++ ) {
1748                         map_list1[ jmap1 ] = astAnnul( map_list1[ jmap1 ] );
1749                      }
1750                      map_list1 = astFree( map_list1 );
1751                   }
1752                   invert_list1 = astFree( invert_list1 );
1753 
1754                   if( map_list2 ) {
1755                      for( jmap2 = 0; jmap2 < nmap2; jmap2++ ) {
1756                         map_list2[ jmap2 ] = astAnnul( map_list2[ jmap2 ] );
1757                      }
1758                      map_list2 = astFree( map_list2 );
1759                   }
1760                   invert_list2 = astFree( invert_list2 );
1761 
1762                }
1763             }
1764 
1765 /* Update Mapping list. */
1766 /* ==================== */
1767 /* If adjacent CmpMaps can be combined, then annul the original pointers. */
1768             if ( astOK && simpler ) {
1769                ( *map_list )[ imap1 ] = astAnnul( ( *map_list )[ imap1 ] );
1770                ( *map_list )[ imap2 ] = astAnnul( ( *map_list )[ imap2 ] );
1771 
1772 /* Insert the pointer to the replacement CmpMap and initialise its
1773    invert flag. */
1774                ( *map_list )[ imap1 ] = new;
1775                ( *invert_list )[ imap1 ] = 0;
1776 
1777 /* Loop to close the resulting gap by moving subsequent elements down
1778    in the arrays. */
1779                for ( imap = imap2 + 1; imap < *nmap; imap++ ) {
1780                   ( *map_list )[ imap - 1 ] = ( *map_list )[ imap ];
1781                   ( *invert_list )[ imap - 1 ] = ( *invert_list )[ imap ];
1782                }
1783 
1784 /* Clear the vacated elements at the end. */
1785                ( *map_list )[ *nmap - 1 ] = NULL;
1786                ( *invert_list )[ *nmap - 1 ] = 0;
1787 
1788 /* Decrement the Mapping count and return the index of the first
1789    modified element. */
1790                ( *nmap )--;
1791                result = imap1;
1792             }
1793          }
1794       }
1795    }
1796 
1797 /* If we are merging the Mappings in series, and if the nominated CmpMap
1798    is a parallel CmpMap, and if the lower neighbour is a PermMap, it may
1799    be possible to swap the PermMap and the CmpMap. This may allow one of
1800    the two swapped Mappings to merge with its new neighbour.
1801    ==================================================================== */
1802 
1803 /* Only do this if no simplification occurred above, and if the Mappings
1804    are being merged in series, and if the nominated Mapping is not the
1805    first in the list. */
1806    if( result == -1 && where > 0 ){
1807 
1808 /* Obtain the indices of the two potential Mappings to be swapped. */
1809       imap1 = where - 1;
1810       imap2 = where;
1811 
1812 /* Obtain a pointer to the CmpMap. */
1813       cmpmap2 = (AstCmpMap *) ( *map_list )[ imap2 ];
1814 
1815 /* Obtain the Class string of the first (previous) Mapping and
1816    determine if it is a PermMap. Also check that the nominated Mapping is
1817    a parallel CmpMap. */
1818       class = astGetClass( ( *map_list )[ imap1 ] );
1819       if ( astOK && !strcmp( class, "PermMap" ) && !cmpmap2->series) {
1820 
1821 /* Indicate we have no new Mapping to store. */
1822          new = NULL;
1823 
1824 /* If suitable, obtain a pointer to the PermMap. */
1825          permmap1 = (AstPermMap *) ( *map_list )[ imap1 ];
1826 
1827 /* Obtain the current values of the Invert attribute in the Mappings. */
1828          invert1 = astGetInvert( permmap1 );
1829          invert2 = astGetInvert( cmpmap2 );
1830 
1831 /* Temporarily set the Invert attributes of both Mappings to the values
1832    supplied in the "invert_list" parameter. */
1833          astSetInvert( permmap1, ( *invert_list )[ imap1 ] );
1834          astSetInvert( cmpmap2, ( *invert_list )[ imap2 ] );
1835 
1836 /* Get the number of inputs and outputs for the PermMap.*/
1837          npout = astGetNout( permmap1 );
1838          npin = astGetNin( permmap1 );
1839 
1840 /* Get the number of inputs and outputs for the two components of the
1841    nominated parallel CmpMap. */
1842          nin2a = astGetNin( cmpmap2->map1 );
1843          nin2b = astGetNin( cmpmap2->map2 );
1844          nout2a = astGetNout( cmpmap2->map1 );
1845          nout2b = astGetNout( cmpmap2->map2 );
1846 
1847 /* Get the input and output axis permutation arrays and the constants
1848    array from the PermMap */
1849          inperm =astGetInPerm( permmap1 );
1850          outperm =astGetOutPerm( permmap1 );
1851          conperm = astGetConstants( permmap1 );
1852 
1853 /* In order to swap the Mappings, the PermMap outputs which feed the
1854    inputs of the first component of the parallel CmpMap must be copied
1855    from a contiguous block at the end of the list of PermMap inputs, or
1856    must all be assigned constant values. Likewise, the PermMap outputs which
1857    feed the inputs of the second component of the parallel CmpMap must be
1858    copied from a contiguous block at the beggining of the list of PermMap
1859    inputs or must be assigned constant values. Also, there must be a
1860    one-to-one correspondance between inputs and outputs in the PermMap.
1861    Check that the first block of nin2a PermMap outputs are copied from
1862    the last block of nin2a PermMap inputs (and vica-versa) or are constant. */
1863          canswap = ( npin == npout );
1864          aconstants = ( outperm[ 0 ] < 0 );
1865 
1866          for( i = 0, j = npin - nin2a; i < nin2a; i++, j++ ) {
1867             if( aconstants ) {
1868                if( outperm[ i ] >= 0 ) {
1869                   canswap = 0;
1870                   break;
1871                }
1872 
1873             } else if( outperm[ i ] != j || inperm[ j ] != i ) {
1874                canswap = 0;
1875                break;
1876             }
1877          }
1878 
1879 /* Check that the first block of nin2b PermMap inputs are copied from
1880    the last block of nin2b PermMap outputs, and vica-versa. */
1881          bconstants = ( outperm[ nin2a ] < 0 );
1882          for( i = 0, j = npout - nin2b; i < nin2b; i++, j++ ) {
1883             if( bconstants ) {
1884                if( outperm[ j ] >= 0 ) {
1885                   canswap = 0;
1886                   break;
1887                }
1888             } else if( inperm[ i ] != j || outperm[ j ] != i ) {
1889                canswap = 0;
1890                break;
1891             }
1892          }
1893 
1894 /* If the Mappings can be swapped.. */
1895          new_pm = NULL;
1896          new_cm = NULL;
1897          qa = NULL;
1898          qb = NULL;
1899          if( canswap ) {
1900 
1901 /* Temporarily set the Invert attributes of the component Mappings to the
1902    values they had when the CmpMap was created. */
1903             invert2a = astGetInvert( cmpmap2->map1 );
1904             invert2b = astGetInvert( cmpmap2->map2 );
1905             astSetInvert( cmpmap2->map1, cmpmap2->invert1 );
1906             astSetInvert( cmpmap2->map2, cmpmap2->invert2 );
1907 
1908 /* If any PermMap outputs are constant, we will need the results of
1909    transforming these constants using the CmpMap which follows. */
1910             if( aconstants || bconstants ) {
1911 
1912 /* Transform a set of bad inputs using the PermMap. This will assign the
1913    PermMap constant to any fixed outputs. */
1914                p = astMalloc( sizeof( double )*(size_t) npin );
1915                q = astMalloc( sizeof( double )*(size_t) npout );
1916                qa = astMalloc( sizeof( double )*(size_t) nout2a );
1917                qb = astMalloc( sizeof( double )*(size_t) nout2b );
1918                if( astOK ) {
1919                   for( i = 0; i < npin; i++ ) p[ i ] = AST__BAD;
1920                   astTranN( permmap1, 1, npin, 1, p, 1, npout, 1, q );
1921 
1922 /* Transform the PermMap outputs using the two component Mappings in the
1923    CmpMap. */
1924                   astTranN( cmpmap2->map1, 1, nin2a, 1, q, 1, nout2a, 1, qa );
1925                   astTranN( cmpmap2->map2, 1, nin2b, 1, q + nin2a, 1, nout2b, 1, qb );
1926 
1927                }
1928                p = astFree( p );
1929                q = astFree( q );
1930             }
1931 
1932 /* If necessary, create a UnitMap to replace a Mapping which has constant
1933    outputs. The number of axes for the UnitMap is chosen to give the
1934    correct total number of inputs for the final parallel CmpMap. At the
1935    same time determine the number of inputs needed by the final PermMap. */
1936             if( aconstants ) {
1937                nunit = npin - nin2b;
1938                npin_new = nout2b + nunit;
1939             } else if( bconstants ) {
1940                nunit = npin - nin2a;
1941                npin_new = nout2a + nunit;
1942             } else {
1943                nunit = 0;
1944                npin_new = nout2a + nout2b;
1945             }
1946             unit = nunit ? astUnitMap( nunit, "", status ) : NULL;
1947 
1948 /* Determine the number of outputs for the final PermMap and allocate memory
1949    for its permutation arrays. */
1950             npout_new = nout2a + nout2b;
1951             outperm_new = astMalloc( sizeof( int )*(size_t) npout_new );
1952             inperm_new = astMalloc( sizeof( int )*(size_t) npin_new );
1953             const_new = astMalloc( sizeof( double )*(size_t) ( npout_new + npin_new ) );
1954             if( astOK ) {
1955                oconid = 0;
1956 
1957 /* First assign permutations for the second component Mapping, if used. */
1958                if( !bconstants ) {
1959                   for( i = 0, j = npout_new - nout2b; i < nout2b; i++,j++ ) {
1960                      inperm_new[ i ] = j;
1961                      outperm_new[ j ] = i;
1962                   }
1963 
1964 /* Otherwise, store constants */
1965                } else {
1966 
1967                   for( i = 0; i < nunit; i++ ){
1968                      iconid = inperm[ i ];
1969                      if( iconid >= npout ) {
1970                         inperm_new[ i ] = npout_new;
1971 
1972                      } else if( iconid >= 0 ) {
1973                         astError( AST__INTER, "astMapMerge(CmpMap): Swapped PermMap "
1974                                   "input is not constant (internal AST programming "
1975                                   "error)." , status);
1976                         break;
1977 
1978                      } else {
1979                         inperm_new[ i ] = --oconid;
1980                         const_new[ -( oconid + 1 ) ] = conperm[ -( iconid + 1 ) ];
1981                      }
1982                   }
1983 
1984                   for( i = 0, j = npout_new - nout2b; i < nout2b; i++,j++ ) {
1985                      outperm_new[ j ] = --oconid;
1986                      const_new[ -( oconid + 1 ) ] = qb[ i ];
1987                   }
1988 
1989                }
1990 
1991 /* Now assign permutations for the first component Mapping, if used. */
1992                if( !aconstants ) {
1993                   for( i = 0, j = npin_new - nout2a; i < nout2a; i++,j++ ) {
1994                      inperm_new[ j ] = i;
1995                      outperm_new[ i ] = j;
1996                   }
1997 
1998 /* Otherwise, store constants */
1999                } else {
2000 
2001                   for( i = nout2b; i < npin_new; i++ ){
2002                      iconid = inperm[ i - nout2b + nin2b ];
2003                      if( iconid >= npout ) {
2004                         inperm_new[ i ] = npout_new;
2005 
2006                      } else if( iconid >= 0 ) {
2007                         astError( AST__INTER, "astMapMerge(CmpMap): Swapped PermMap "
2008                                   "input is not constant (internal AST programming "
2009                                   "error)." , status);
2010                         break;
2011 
2012                      } else {
2013                         inperm_new[ i ] = --oconid;
2014                         const_new[ -( oconid + 1 ) ] = conperm[ -( iconid + 1 ) ];
2015                      }
2016                   }
2017 
2018                   for( i = 0; i < nout2a; i++ ) {
2019                      outperm_new[ i ] = --oconid;
2020                      const_new[ -( oconid + 1 ) ] = qa[ i ];
2021                   }
2022 
2023                }
2024 
2025 /* Create the new PermMap */
2026                new_pm = astPermMap( npin_new, inperm_new, npout_new,
2027                                     outperm_new, const_new, "", status );
2028 
2029 /* Create the new CmpMap.*/
2030                if( aconstants ) {
2031                   if( unit ) {
2032                      new_cm = astCmpMap( cmpmap2->map2, unit, 0, "", status );
2033                   } else {
2034                      new_cm = astCopy( cmpmap2->map2 );
2035                   }
2036 
2037                } else if( bconstants ) {
2038                   if( unit ) {
2039                      new_cm = astCmpMap( unit, cmpmap2->map1, 0, "", status );
2040                   } else {
2041                      new_cm = astCopy( cmpmap2->map1 );
2042                   }
2043 
2044                } else{
2045                   new_cm = astCmpMap( cmpmap2->map2, cmpmap2->map1, 0, "", status );
2046                }
2047 
2048             }
2049 
2050 /* Free Memory. */
2051             if( unit ) unit = astAnnul( unit );
2052             outperm_new = astFree( outperm_new );
2053             inperm_new = astFree( inperm_new );
2054             const_new = astFree( const_new );
2055             if( aconstants || bconstants ) {
2056                qa = astFree( qa );
2057                qb = astFree( qb );
2058             }
2059 
2060 /* Re-instate the original Invert attributes in the component Mappings. */
2061             astSetInvert( cmpmap2->map1, invert2a );
2062             astSetInvert( cmpmap2->map2, invert2b );
2063 
2064          }
2065 
2066 /* Release the arrays holding the input and output permutation arrays
2067    and constants copied from the PermMap. */
2068          inperm = astFree( inperm );
2069          outperm = astFree( outperm );
2070          conperm = astFree( conperm );
2071 
2072 /* Re-instate the original values of the Invert attributes of both
2073    Mappings. */
2074          astSetInvert( permmap1, invert1 );
2075          astSetInvert( cmpmap2, invert2 );
2076 
2077 /* If the Mappings can be swapped... */
2078          if( astOK && canswap ) {
2079 
2080 /* Annul the supplied pointer to the two Mappings. */
2081             ( *map_list )[ imap1 ] = astAnnul( ( *map_list )[ imap1 ] );
2082             ( *map_list )[ imap2 ] = astAnnul( ( *map_list )[ imap2 ] );
2083 
2084 /* Store the new PermMap pointer in the slot previously occupied by the
2085    nominated CmpMap pointer. Likewise, store the invert flag. */
2086             ( *map_list )[ imap2 ] = (AstMapping *) new_pm;
2087             ( *invert_list )[ imap2 ] = astGetInvert( new_pm );
2088 
2089 /* Store the new PermMap pointer in the slot previously occupied by the
2090    nominated CmpMap pointer. Likewise, store the invert flag. */
2091             ( *map_list )[ imap1 ] = (AstMapping *) new_cm;
2092             ( *invert_list )[ imap1 ] = astGetInvert( new_cm );
2093 
2094 /* Return the index of the first modified element. */
2095             result = imap1;
2096 
2097          }
2098       }
2099    }
2100 
2101 /* If an error occurred, clear the result value. */
2102    if ( !astOK ) result = -1;
2103 
2104 /* Return the result. */
2105    return result;
2106 }
2107 
MapSplit1(AstMapping * this,int nin,const int * in,AstMapping ** map,int * status)2108 static int *MapSplit1( AstMapping *this, int nin, const int *in, AstMapping **map, int *status ){
2109 /*
2110 *  Name:
2111 *     MapSplit1
2112 
2113 *  Purpose:
2114 *     Create a Mapping representing a subset of the inputs of an existing
2115 *     Mapping.
2116 
2117 *  Type:
2118 *     Private function.
2119 
2120 *  Synopsis:
2121 *     #include "cmpmap.h"
2122 *     int *MapSplit1( AstMapping *this, int nin, const int *in, AstMapping **map )
2123 
2124 *  Class Membership:
2125 *     CmpMap method
2126 
2127 *  Description:
2128 *     This function performs the work for the astMapSplit method. It
2129 *     first invokes the astMapSplit method to see if the forward
2130 *     transformation of the supplied Mapping (not necessarily a CmpMap)
2131 *     can be split as requested. If this is not possible it invokes MapSplit2
2132 *     which attempts an inverse approach to the problem. For each possible
2133 *     sub-sets of the Mapping outputs it call astMapSplit to see if the
2134 *     sub-set of outputs are generated from the selected inputs.
2135 
2136 *  Parameters:
2137 *     this
2138 *        Pointer to the Mapping to be split. It is not assumed to be a CmpMap.
2139 *     nin
2140 *        The number of inputs to pick from "this".
2141 *     in
2142 *        Pointer to an array of indices (zero based) for the inputs which
2143 *        are to be picked. This array should have "nin" elements. If "Nin"
2144 *        is the number of inputs of the supplied Mapping, then each element
2145 *        should have a value in the range zero to Nin-1.
2146 *     map
2147 *        Address of a location at which to return a pointer to the new
2148 *        Mapping. This Mapping will have "nin" inputs (the number of
2149 *        outputs may be different to "nin"). A NULL pointer will be
2150 *        returned if the supplied Mapping has no subset of outputs which
2151 *        depend only on the selected inputs.
2152 
2153 *  Returned Value:
2154 *     A pointer to a dynamically allocated array of ints. The number of
2155 *     elements in this array will equal the number of outputs for the
2156 *     returned Mapping. Each element will hold the index of the
2157 *     corresponding output in the supplied Mapping. The array should be
2158 *     freed using astFree when no longer needed. A NULL pointer will
2159 *     be returned if no output Mapping can be created.
2160 
2161 *  Notes:
2162 *     - If this function is invoked with the global error status set,
2163 *     or if it should fail for any reason, then NULL values will be
2164 *     returned as the function value and for the "map" pointer.
2165 */
2166 
2167 /* Local Variables: */
2168    int *result;       /* Axis order to return */
2169 
2170 /* Initialise */
2171    result = NULL;
2172    *map = NULL;
2173 
2174 /* Check the global error status. */
2175    if ( !astOK ) return result;
2176 
2177 /* First see if the forward transformation can be split as requested. */
2178    result = astMapSplit( this, nin, in, map );
2179 
2180 /* If forward transformation could not be split, we attempt to split the
2181    inverse transformation by selecting every possible sub-set of Mapping
2182    outputs until one is found which is fed by the requested mapping inputs. */
2183    if( !result ) result = MapSplit2( this, nin, in, map, status );
2184 
2185 /* Free returned resources if an error has occurred. */
2186    if( !astOK ) {
2187       result = astFree( result );
2188       *map = astAnnul( *map );
2189    }
2190 
2191 /* Return the list of output indices. */
2192    return result;
2193 }
2194 
MapSplit2(AstMapping * this,int nin,const int * in,AstMapping ** map,int * status)2195 static int *MapSplit2( AstMapping *this, int nin, const int *in, AstMapping **map, int *status ){
2196 /*
2197 *  Name:
2198 *     MapSplit2
2199 
2200 *  Purpose:
2201 *     Create a Mapping representing a subset of the inputs of an existing
2202 *     Mapping.
2203 
2204 *  Type:
2205 *     Private function.
2206 
2207 *  Synopsis:
2208 *     #include "cmpmap.h"
2209 *     int *MapSplit2( AstMapping *this, int nin, const int *in, AstMapping **map )
2210 
2211 *  Class Membership:
2212 *     CmpMap method
2213 
2214 *  Description:
2215 *     This function attempts to split the supplied Mapping using an
2216 *     inverse approach to the problem. For each possible sub-sets of the
2217 *     Mapping outputs it call astMapSplit to see if the sub-set of outputs
2218 *     are generated from the selected inputs.
2219 
2220 *  Parameters:
2221 *     this
2222 *        Pointer to the Mapping to be split. It is not assumed to be a CmpMap.
2223 *     nin
2224 *        The number of inputs to pick from "this".
2225 *     in
2226 *        Pointer to an array of indices (zero based) for the inputs which
2227 *        are to be picked. This array should have "nin" elements. If "Nin"
2228 *        is the number of inputs of the supplied Mapping, then each element
2229 *        should have a value in the range zero to Nin-1.
2230 *     map
2231 *        Address of a location at which to return a pointer to the new
2232 *        Mapping. This Mapping will have "nin" inputs (the number of
2233 *        outputs may be different to "nin"). A NULL pointer will be
2234 *        returned if the supplied Mapping has no subset of outputs which
2235 *        depend only on the selected inputs.
2236 
2237 *  Returned Value:
2238 *     A pointer to a dynamically allocated array of ints. The number of
2239 *     elements in this array will equal the number of outputs for the
2240 *     returned Mapping. Each element will hold the index of the
2241 *     corresponding output in the supplied Mapping. The array should be
2242 *     freed using astFree when no longer needed. A NULL pointer will
2243 *     be returned if no output Mapping can be created.
2244 
2245 *  Notes:
2246 *     - If this function is invoked with the global error status set,
2247 *     or if it should fail for any reason, then NULL values will be
2248 *     returned as the function value and for the "map" pointer.
2249 */
2250 
2251 /* Local Variables: */
2252    AstMapping *map2;  /* Subset Mapping */
2253    AstMapping *this2; /* Inverted copy of the supplied Mapping */
2254    int *out;          /* Selected output indices */
2255    int *result;       /* Axis order to return */
2256    int *result2;      /* Axis order for current output subset */
2257    int i;             /* Loop count */
2258    int iscmp;         /* Is "this" a CmpMap? */
2259    int j;             /* Loop count */
2260    int mout;          /* Number of selected outputs */
2261    int nin2;          /* Number of inputs fed by current outputs */
2262    int nout;          /* The number of outputs from the supplied Mapping */
2263    int ok;            /* Are all required inputs fed by current outputs? */
2264 
2265 /* Initialise */
2266    result = NULL;
2267    *map = NULL;
2268 
2269 /* Check the global error status. */
2270    if ( !astOK ) return result;
2271 
2272 /* Get the number of Mapping outputs. */
2273    nout = astGetNout( this );
2274 
2275 /* Get an inverted copy of the Mapping. We do this rather than inverting
2276    the supplied Maping in case an error occurs which may leave the
2277    supplied Mapping inverted. */
2278    this2 = astCopy( this );
2279    astInvert( this2 );
2280 
2281 /* Note if the Mapping is a CmpMap. */
2282    iscmp = astIsACmpMap( this );
2283 
2284 /* Allocate memory to hold the selected output indices. */
2285    out = astMalloc( nout*sizeof( int ) );
2286 
2287 /* Loop round all useful subset sizes. */
2288    if( out ) {
2289       for( mout = 1; mout < nout && !result; mout++ ) {
2290 
2291 /* Initialise the first subset of outputs to check at the current subset
2292    size. */
2293          for( i = 0; i < mout; i++ ) out[ i ] = 0;
2294 
2295 /* Loop round all ways of picking a subset of "mout" outputs from the total
2296    available "nout" outputs. */
2297          while( ! result ) {
2298 
2299 /* Skip this subset if it refers to any axis index more than once. */
2300             ok = 1;
2301             for( i = 1; i < mout && ok; i++ ) {
2302                for( j = 0; j < i; j++ ) {
2303                   if( out[ i ] == out[ j ] ) {
2304                      ok = 0;
2305                      break;
2306                   }
2307                }
2308             }
2309             if( ok ) {
2310 
2311 /* Attempt to split the inverted Mapping using the current subset of
2312    outputs. Take care to avoid an infinite loop if "this" is a CmpMap. */
2313                if( iscmp ) {
2314                   result2 = MapSplit0( this2, mout, out, &map2, 1, status );
2315                } else {
2316                   result2 = astMapSplit( this2, mout, out, &map2 );
2317                }
2318 
2319 /* If succesful... */
2320                if( result2 ) {
2321 
2322 /* See if the inputs that feed the current subset of outputs are the same
2323    as the inputs specified by the caller (and in the same order). */
2324                   nin2 = astGetNout( map2 );
2325                   ok = ( nin2 == nin );
2326                   if( ok ) {
2327                      for( i = 0; i < nin; i++ ) {
2328                         if( in[ i ] != result2[ i ] ) {
2329                            ok = 0;
2330                            break;
2331                         }
2332                      }
2333                   }
2334 
2335 /* If so, set up the values returned to the caller. */
2336                   if( ok ) {
2337                      result = astStore( result, out, mout*sizeof(int) );
2338                      astInvert( map2 );
2339                      *map = astClone( map2 );
2340                   }
2341 
2342 /* Free resources. */
2343                   result2 = astFree( result2 );
2344                   map2 = astAnnul( map2 );
2345                }
2346             }
2347 
2348 /* Increment the first axis index. */
2349             i = 0;
2350             out[ i ]++;
2351 
2352 /* If the incremented axis index is now too high, reset it to zero and
2353    increment the next higher axis index. Do this until an incremented axis
2354    index is not too high. */
2355             while( out[ i ] == nout ) {
2356                out[ i++ ] = 0;
2357 
2358                if( i < mout ) {
2359                   out[ i ]++;
2360                } else {
2361                   break;
2362                }
2363             }
2364 
2365 /* If all subsets have been checked break out of the loop. */
2366             if( i == mout ) break;
2367 
2368          }
2369       }
2370    }
2371 
2372 /* Free resources. */
2373    out = astFree( out );
2374    this2 = astAnnul( this2 );
2375 
2376 /* Free returned resources if an error has occurred. */
2377    if( !astOK ) {
2378       result = astFree( result );
2379       *map = astAnnul( *map );
2380    }
2381 
2382 /* Return the list of output indices. */
2383    return result;
2384 }
2385 
MapSplit0(AstMapping * this_mapping,int nin,const int * in,AstMapping ** map,int reentry,int * status)2386 static int *MapSplit0( AstMapping *this_mapping, int nin, const int *in,
2387                        AstMapping **map, int reentry, int *status ){
2388 /*
2389 *  Name:
2390 *     MapSplit0
2391 
2392 *  Purpose:
2393 *     Create a Mapping representing a subset of the inputs of an existing
2394 *     CmpMap.
2395 
2396 *  Type:
2397 *     Private function.
2398 
2399 *  Synopsis:
2400 *     #include "cmpmap.h"
2401 *     int *MapSplit0( AstMapping *this, int nin, const int *in,
2402 *                     AstMapping **map, int reentry, int *status )
2403 
2404 *  Class Membership:
2405 *     CmpMap method
2406 
2407 *  Description:
2408 *     This function creates a new Mapping by picking specified inputs from
2409 *     an existing CmpMap. This is only possible if the specified inputs
2410 *     correspond to some subset of the CmpMap outputs. That is, there
2411 *     must exist a subset of the CmpMap outputs for which each output
2412 *     depends only on the selected CmpMap inputs, and not on any of the
2413 *     inputs which have not been selected. If this condition is not met
2414 *     by the supplied CmpMap, then a NULL Mapping is returned.
2415 
2416 *  Parameters:
2417 *     this
2418 *        Pointer to the CmpMap to be split (the CmpMap is not actually
2419 *        modified by this function).
2420 *     nin
2421 *        The number of inputs to pick from "this".
2422 *     in
2423 *        Pointer to an array of indices (zero based) for the inputs which
2424 *        are to be picked. This array should have "nin" elements. If "Nin"
2425 *        is the number of inputs of the supplied CmpMap, then each element
2426 *        should have a value in the range zero to Nin-1.
2427 *     map
2428 *        Address of a location at which to return a pointer to the new
2429 *        Mapping. This Mapping will have "nin" inputs (the number of
2430 *        outputs may be different to "nin"). A NULL pointer will be
2431 *        returned if the supplied CmpMap has no subset of outputs which
2432 *        depend only on the selected inputs.
2433 *     reentry
2434 *        Set to zero if this is a top level entry, and non-zero if it is
2435 *        a recursive entry.
2436 *     status
2437 *        Pointer to the inherited status variable.
2438 
2439 *  Returned Value:
2440 *     A pointer to a dynamically allocated array of ints. The number of
2441 *     elements in this array will equal the number of outputs for the
2442 *     returned Mapping. Each element will hold the index of the
2443 *     corresponding output in the supplied CmpMap. The array should be
2444 *     freed using astFree when no longer needed. A NULL pointer will
2445 *     be returned if no output Mapping can be created.
2446 
2447 *  Notes:
2448 *     - If this function is invoked with the global error status set,
2449 *     or if it should fail for any reason, then NULL values will be
2450 *     returned as the function value and for the "map" pointer.
2451 */
2452 
2453 /* Local Variables: */
2454    AstCmpMap *this;
2455    AstMapping **map_list;
2456    AstMapping *amap;
2457    AstMapping *bmap;
2458    AstPermMap *pmap;
2459    int *aout;
2460    int *cin;
2461    int *cout;
2462    int *inp;
2463    int *invert_list;
2464    int *outp;
2465    int *p;
2466    int *result;
2467    int doperm;
2468    int i;
2469    int ibot;
2470    int ibotout;
2471    int iin;
2472    int imap;
2473    int iout;
2474    int itop;
2475    int j;
2476    int naout;
2477    int ncin;
2478    int ncout;
2479    int nmap;
2480    int npin;
2481    int npout;
2482    int ok;
2483    int old_inv;
2484    int t;
2485 
2486 
2487 /* Initialise */
2488    result = NULL;
2489    *map = NULL;
2490 
2491 /* Check the global error status. */
2492    if ( !astOK ) return result;
2493 
2494 /* Get a pointer to the CmpMap structure. */
2495    this = (AstCmpMap *) this_mapping;
2496 
2497 /* Get the number of inputs and outputs in the supplied CmpMap. */
2498    npin = astGetNin( this );
2499    npout = astGetNout( this );
2500 
2501 /* Check all input axis indices are valid. */
2502    ok = 1;
2503    for( i = 0; i < nin; i++ ) {
2504       if( in[ i ] < 0 || in[ i ] >= npin ) {
2505          ok = 0;
2506          break;
2507       }
2508    }
2509 
2510 /* If OK, proceed. */
2511    if( ok ) {
2512 
2513 /* Initialise dynamic arrays of Mapping pointers and associated Invert
2514    flags. */
2515       nmap = 0;
2516       map_list = NULL;
2517       invert_list = NULL;
2518 
2519 /* Decompose the CmpMap into a sequence of Mappings to be applied in
2520    series or parallel, as appropriate, and an associated list of
2521    Invert flags. */
2522       (void) astMapList( this_mapping, this->series, astGetInvert( this ),
2523                          &nmap, &map_list, &invert_list );
2524 
2525 /* First handle lists of Mapping in series. */
2526       if( this->series ) {
2527 
2528 /* Initialise the array of inputs to be split from the next component
2529    Mapping. */
2530          ncin = nin;
2531          cin = astStore( NULL, in, sizeof( int )*nin );
2532 
2533 /* Loop round all the component Mappings that are combined in series to form
2534    the supplied CmpMap. */
2535          for( imap = 0; imap < nmap && cin; imap++ ) {
2536 
2537 /* Temporarily reset the Invert attribute within the commponent Mapping back
2538    to the value it had when the CmpMap was created. */
2539             old_inv = astGetInvert( map_list[ imap ] );
2540             astSetInvert(  map_list[ imap ], invert_list[ imap ] );
2541 
2542 /* Attempt to split the component Mapping using the current list of
2543    inputs. */
2544             cout = MapSplit1( map_list[ imap ], ncin, cin, &amap, status );
2545 
2546 /* If the split could be done... */
2547             if( amap ) {
2548 
2549 /* The outputs that correspond to the picked inputs become the inputs to
2550    be picked from the next component Mapping. */
2551                (void) astFree( cin );
2552                cin = cout;
2553                ncin = astGetNout( amap );
2554 
2555 /* Combine the split Mapping in series with the earlier split Mappings. */
2556                if( *map ) {
2557                   bmap = (AstMapping *) astCmpMap( *map, amap, 1, " ", status );
2558                   amap = astAnnul( amap );
2559                   (void) astAnnul( *map );
2560                   *map = bmap;
2561                } else {
2562                   *map = amap;
2563                }
2564 
2565 /* If the split could not be done, free the array of Mapping inputs to
2566    indicate that no more component Mappings need be checked. */
2567             } else {
2568                cin = astFree( cin );
2569                cout = astFree( cout );
2570             }
2571 
2572 /* Re-instate the original value of the Invert attribute within the
2573    commponent Mapping. */
2574             astSetInvert(  map_list[ imap ], old_inv );
2575          }
2576 
2577 /* Return the final array of output indices. */
2578          result = cin;
2579 
2580 /* Now handle lists of Mapping in parallel. */
2581       } else {
2582 
2583 /* Allocate work space. */
2584          outp = astMalloc( sizeof(int)*(size_t)nin );
2585          inp = astMalloc( sizeof(int)*(size_t)nin );
2586          cin = astMalloc( sizeof(int)*(size_t)npin );
2587          cout = astMalloc( sizeof(int)*(size_t)npout );
2588          if( astOK ) {
2589 
2590 /* The caller may have selected the Mapping inputs in any order, so we
2591    need to create a PermMap which will permute the inputs from the
2592    requested order to the order used by the CmpMap. First fill the outperm
2593    work array with its own indices. */
2594             for( i = 0; i < nin; i++ ) outp[ i ] = i;
2595 
2596 /* Sort the outperm work array so that it accesses the array of input indices
2597    in ascending order */
2598             for( j = nin - 1; j > 0; j-- ) {
2599                p = outp;
2600                for( i = 0; i < j; i++,p++ ) {
2601                   if( in[ p[0] ] > in[ p[1] ] ) {
2602                      t = p[0];
2603                      p[0] = p[1];
2604                      p[1] = t;
2605                   }
2606                }
2607             }
2608 
2609 /* Create the inperm array which is the inverse of the above outperm
2610    array. Note if the permutation is necessary. */
2611             doperm = 0;
2612             for( i = 0; i < nin; i++ ) {
2613                if( outp[ i ] != i ) doperm = 1;
2614                inp[ outp[ i ] ] = i;
2615             }
2616 
2617 /* Create a PermMap which reorders the inputs into ascending order. */
2618             pmap = doperm ? astPermMap( nin, inp, nin, outp, NULL, "", status ) : NULL;
2619 
2620 /* Store the sorted input indices in the inp work array. */
2621             for( i = 0; i < nin; i++ ) {
2622                inp[ i ] = in[ outp[ i ] ];
2623             }
2624 
2625 /* Initialise the index within the supplied CmpMap of the last (highest)
2626    input in the current component Mapping. */
2627             itop = -1;
2628 
2629 /* Initialise the index within the supplied CmpMap of the first (lowest)
2630    output for the current component Mapping. */
2631             ibotout = 0;
2632 
2633 /* Initialise the index within the supplied CmpMap of the current picked input. */
2634             iin = 0;
2635 
2636 /* Initialise the index of the next returned output index. */
2637             ncout = 0;
2638 
2639 /* Loop round all the component Mappings that are combined in series to form
2640    the supplied CmpMap. */
2641             for( imap = 0; imap < nmap && cout; imap++ ) {
2642 
2643 /* Temporarily reset the Invert attribute within the component Mapping back
2644    to the value it had when the CmpMap was created. */
2645                old_inv = astGetInvert( map_list[ imap ] );
2646                astSetInvert(  map_list[ imap ], invert_list[ imap ] );
2647 
2648 /* Get the index within the supplied CmpMap of the first (lowest) input in
2649    the current component Mapping. */
2650                ibot = itop + 1;
2651 
2652 /* Get the index within the supplied CmpMap of the last (highest) input in
2653    the current component Mapping. */
2654                itop += astGetNin( map_list[ imap ] );
2655 
2656 /* Get the zero-based indicies of the required inputs that feed the current
2657    component Mapping. */
2658                ncin = 0;
2659                while( iin < nin && inp[ iin ] <= itop ) {
2660                   cin[ ncin++ ] = inp[ iin++ ] - ibot;
2661                }
2662 
2663 /* Skip components from which no inputs are being picked. */
2664                if( ncin > 0 ) {
2665 
2666 /* Attempt to split the component Mapping using the current list of inputs. */
2667                   aout = MapSplit1( map_list[ imap ], ncin, cin, &amap,
2668                                     status );
2669 
2670 /* If successful... */
2671                   if( amap ) {
2672 
2673 /* Correct the output indices so that they refer to the numbering scheme
2674    of the total CmpMap, and append to the total list of output indices. */
2675                      naout = astGetNout( amap );
2676                      for( iout = 0; iout < naout; iout++ ) {
2677                         cout[ ncout++ ] = aout[ iout ] + ibotout;
2678                      }
2679 
2680 /* Combine the split Mapping in parallel with the earlier split Mappings. */
2681                      if( *map ) {
2682                         bmap = (AstMapping *) astCmpMap( *map, amap, 0, " ",
2683                                                          status );
2684                         amap = astAnnul( amap );
2685                         (void) astAnnul( *map );
2686                         *map = bmap;
2687                      } else {
2688                         *map = amap;
2689                      }
2690 
2691 /* If the component Mapping could not be split, free the cout array to
2692    indicate that no more component Mappings need be considered. */
2693                   } else {
2694                      cout = astFree( cout );
2695                   }
2696 
2697 /* Free remaining resources. */
2698                   aout = astFree( aout );
2699                }
2700 
2701 /* Update the index within the supplied CmpMap of the first (lowest) output in
2702    the next component Mapping. */
2703                ibotout += astGetNout( map_list[ imap ] );
2704 
2705 /* Re-instate the original value of the Invert attribute within the
2706    commponent Mapping. */
2707                astSetInvert(  map_list[ imap ], old_inv );
2708             }
2709 
2710 /* If the requested inputs could be split from the total CmpMap, add in any
2711    PermMap needed to re-order the inputs. */
2712             if( cout && ncout ){
2713                if( doperm ) {
2714                   bmap = (AstMapping *) astCmpMap( pmap, *map, 1, "", status );
2715                   (void) astAnnul( *map );
2716                   *map = bmap;
2717                }
2718 
2719 /* Also return the list of output indices. */
2720                result = cout;
2721                cout = NULL;
2722             }
2723 
2724 /* Free remaining resources. */
2725             if( pmap ) pmap = astAnnul( pmap );
2726          }
2727          outp = astFree( outp );
2728          inp = astFree( inp );
2729          cin = astFree( cin );
2730          cout = astFree( cout );
2731       }
2732 
2733 /* Loop to annul all the Mapping pointers in the list. */
2734       for ( i = 0; i < nmap; i++ ) map_list[ i ] = astAnnul( map_list[ i ] );
2735 
2736 /* Free the dynamic arrays. */
2737       map_list = astFree( map_list );
2738       invert_list = astFree( invert_list );
2739 
2740    }
2741 
2742 /* Mappings that have no outputs cannot be used. */
2743    if( !result && *map ) *map = astAnnul( *map );
2744 
2745 /* If the above method failed to split the CmpMap, we attempt to split the
2746    inverse transformation by selecting every possible sub-set of Mapping
2747    outputs until one is found which is fed by the requested mapping inputs. */
2748    if( !result && !reentry ) result = MapSplit2( this_mapping, nin, in, map,
2749                                                  status );
2750 
2751 /* Free returned resources if an error has occurred. */
2752    if( !astOK ) {
2753       result = astFree( result );
2754       *map = astAnnul( *map );
2755    }
2756 
2757 /* Return the list of output indices. */
2758    return result;
2759 }
2760 
MapSplit(AstMapping * this,int nin,const int * in,AstMapping ** map,int * status)2761 static int *MapSplit( AstMapping *this, int nin, const int *in,
2762                       AstMapping **map, int *status ){
2763 /*
2764 *  Name:
2765 *     MapSplit
2766 
2767 *  Purpose:
2768 *     Create a Mapping representing a subset of the inputs of an existing
2769 *     CmpMap.
2770 
2771 *  Type:
2772 *     Private function.
2773 
2774 *  Synopsis:
2775 *     #include "cmpmap.h"
2776 *     int *MapSplit( AstMapping *this, int nin, const int *in,
2777 *                    AstMapping **map, int *status )
2778 
2779 *  Class Membership:
2780 *     CmpMap method (over-rides the protected astMapSplit method
2781 *     inherited from the Mapping class).
2782 
2783 *  Description:
2784 *     This function is the main entry point for the astMapSplit method.
2785 *     It is a simple wrapper for MapSplit0 which calls MapSplit0
2786 *     indicating that this is a top-level entry.
2787 
2788 *  Parameters:
2789 *     this
2790 *        Pointer to the CmpMap to be split (the CmpMap is not actually
2791 *        modified by this function).
2792 *     nin
2793 *        The number of inputs to pick from "this".
2794 *     in
2795 *        Pointer to an array of indices (zero based) for the inputs which
2796 *        are to be picked. This array should have "nin" elements. If "Nin"
2797 *        is the number of inputs of the supplied CmpMap, then each element
2798 *        should have a value in the range zero to Nin-1.
2799 *     map
2800 *        Address of a location at which to return a pointer to the new
2801 *        Mapping. This Mapping will have "nin" inputs (the number of
2802 *        outputs may be different to "nin"). A NULL pointer will be
2803 *        returned if the supplied CmpMap has no subset of outputs which
2804 *        depend only on the selected inputs.
2805 *     status
2806 *        Pointer to the inherited status variable.
2807 
2808 *  Returned Value:
2809 *     A pointer to a dynamically allocated array of ints. The number of
2810 *     elements in this array will equal the number of outputs for the
2811 *     returned Mapping. Each element will hold the index of the
2812 *     corresponding output in the supplied CmpMap. The array should be
2813 *     freed using astFree when no longer needed. A NULL pointer will
2814 *     be returned if no output Mapping can be created.
2815 
2816 *  Notes:
2817 *     - If this function is invoked with the global error status set,
2818 *     or if it should fail for any reason, then NULL values will be
2819 *     returned as the function value and for the "map" pointer.
2820 */
2821    return MapSplit0( this, nin, in, map, 0, status );
2822 }
2823 
PatternCheck(int val,int check,int ** list,int * list_len,int * status)2824 static int PatternCheck( int val, int check, int **list, int *list_len, int *status ){
2825 /*
2826 *  Name:
2827 *     Looping
2828 
2829 *  Purpose:
2830 *     Check for repeating patterns in a set of integer values.
2831 
2832 *  Type:
2833 *     Private function.
2834 
2835 *  Synopsis:
2836 *     #include "cmpmap.h"
2837 *     int PatternCheck( int val, int nmap, int **mlist, int **nlist, int *list_len )
2838 
2839 *  Class Membership:
2840 *     CmpMap member function.
2841 
2842 *  Description:
2843 *     This function appends a supplied integer to a dynamic list, creating
2844 *     or expanding the list if necessary.It then optionally, check the
2845 *     list for evidence of repeating patterns. If such a pattern is
2846 *     found, its wavelength is returned.
2847 
2848 *  Parameters:
2849 *     val
2850 *        The integer value to add to the list.
2851 *     check
2852 *        Should a check for reating patterns be performed?
2853 *     list
2854 *        Address of a location at which is stored a pointer to an array
2855 *        holding the values supplied on previous invocations of this
2856 *        function. If a NULL pointer is supplied a new array is allocated.
2857 *        On exit, the supplied value is appended to the end of the array. The
2858 *        array is extended as necessary. The returned pointer should be
2859 *        freed using astFree when no longer needed.
2860 *     list_len
2861 *        Address of a location at which is stored the number of elements
2862 *        in the "list" array.
2863 
2864 *  Returned Value:
2865 *     A non-zero "wavelength" value is returned if there is a repeating
2866 *     pattern is found in the "list" array. Otherwise, zero is returned.
2867 *     The "wavelength" is the number of integer values which constitute a
2868 *     single instance of the pattern.
2869 
2870 *  Notes:
2871 *     - A value of 1 is returned if this function is invoked with the AST
2872 *     error status set, or if it should fail for any reason.
2873 */
2874 
2875 /* Local Variables: */
2876    int *wave[ 30 ];          /* Pointers to start of waves */
2877    int iat;                  /* Index of elements added by this invocation */
2878    int jat;                  /* Index of element condiered next */
2879    int jlo;                  /* Earliest "mlist" entry to consider */
2880    int k;                    /* Index of element within pattern */
2881    int mxwave;               /* Max pattern length to consider */
2882    int iwave;                /* Index of current wave */
2883    int nwave;                /* Number of waves required to mark a pattern */
2884    int result;               /* Returned flag */
2885    int wavelen;              /* Current pattern length */
2886 
2887 /* Check the global status. */
2888    if ( !astOK ) return 1;
2889 
2890 /* Initialise */
2891    result = 0;
2892 
2893 /* If no array has been supplied, create a new array. */
2894    if( !(*list) ) {
2895       *list = astMalloc( 100*sizeof( int ) );
2896       *list_len = 0;
2897    }
2898 
2899 /* Store the new value in the array, extending it if necessary. */
2900    iat = (*list_len)++;
2901    *list = astGrow( *list, *list_len, sizeof( int ) );
2902    if( astOK ) {
2903       (*list)[ iat ] = val;
2904 
2905 /* If required, determine the maximum "wavelength" for looping patterns to be
2906    checked, and store the earliest list entry to consider. We take 3 complete
2907    patterns as evidence of looping, but we only do the check when the
2908    list length is at least 30. */
2909       if( check && *list_len > 29 ){
2910          mxwave = iat/3;
2911          if( mxwave > 50 ) mxwave = 50;
2912          jlo = iat - 3*mxwave;
2913 
2914 /* Search backwards from the end of "list" looking for the most recent
2915    occurence of the supplied "val" value. Limit the search to
2916    wavelengths of no more than the above limit. */
2917          jat = iat - 1;
2918          while( jat >= jlo ) {
2919             if( (*list)[ jat ] == val ) {
2920 
2921 /* When an earlier occurrence of "val" is found, see if the values
2922    which precede it are the same as the values which precede the new
2923    element if "list" added by this invocation. We use 3 complete
2924    patterns as evidence of looping, unless the wavelength is 1 in which
2925    case we use 30 patterns (this is because wavelengths of 1 can occur
2926    in short sequences legitamately). */
2927                wavelen = iat - jat;
2928 
2929                if( wavelen == 1 ) {
2930                   nwave = 30;
2931                   if( nwave > iat ) nwave = iat;
2932                } else {
2933                   nwave = 3;
2934                }
2935 
2936                if( nwave*wavelen <= *list_len ) {
2937                   result = wavelen;
2938                   wave[ 0 ] = *list + *list_len - wavelen;
2939                   for( iwave = 1; iwave < nwave; iwave++ ) {
2940                      wave[ iwave ] = wave[ iwave - 1 ] - wavelen;
2941                   }
2942 
2943                   for( k = 0; k < wavelen; k++ ) {
2944                      for( iwave = 1; iwave < nwave; iwave++ ) {
2945                         if( *wave[ iwave ] != *wave[ 0 ] ) {
2946                            result = 0;
2947                            break;
2948                         }
2949                         wave[ iwave ]++;
2950                      }
2951                      wave[ 0 ]++;
2952                   }
2953                }
2954 
2955 /* Break if we have found a repeating pattern. */
2956                if( result ) break;
2957 
2958             }
2959             jat--;
2960          }
2961       }
2962    }
2963 
2964    if( !astOK ) result= 1;
2965 
2966 /* Return the result.*/
2967    return result;
2968 }
2969 
Rate(AstMapping * this,double * at,int ax1,int ax2,int * status)2970 static double Rate( AstMapping *this, double *at, int ax1, int ax2, int *status ){
2971 /*
2972 *  Name:
2973 *     Rate
2974 
2975 *  Purpose:
2976 *     Calculate the rate of change of a Mapping output.
2977 
2978 *  Type:
2979 *     Private function.
2980 
2981 *  Synopsis:
2982 *     #include "cmpmap.h"
2983 *     result = Rate( AstMapping *this, double *at, int ax1, int ax2, int *status )
2984 
2985 *  Class Membership:
2986 *     CmpMap member function (overrides the astRate method inherited
2987 *     from the Mapping class ).
2988 
2989 *  Description:
2990 *     This function returns the rate of change of a specified output of
2991 *     the supplied Mapping with respect to a specified input, at a
2992 *     specified input position.
2993 
2994 *  Parameters:
2995 *     this
2996 *        Pointer to the Mapping to be applied.
2997 *     at
2998 *        The address of an array holding the axis values at the position
2999 *        at which the rate of change is to be evaluated. The number of
3000 *        elements in this array should equal the number of inputs to the
3001 *        Mapping.
3002 *     ax1
3003 *        The index of the Mapping output for which the rate of change is to
3004 *        be found (output numbering starts at 0 for the first output).
3005 *     ax2
3006 *        The index of the Mapping input which is to be varied in order to
3007 *        find the rate of change (input numbering starts at 0 for the first
3008 *        input).
3009 *     status
3010 *        Pointer to the inherited status variable.
3011 
3012 *  Returned Value:
3013 *     The rate of change of Mapping output "ax1" with respect to input
3014 *     "ax2", evaluated at "at", or AST__BAD if the value cannot be
3015 *     calculated.
3016 
3017 */
3018 
3019 /* Local Variables: */
3020    AstMapping *c1;
3021    AstMapping *c2;
3022    AstCmpMap *map;
3023    double result;
3024    int old_inv1;
3025    int old_inv2;
3026    int nin1;
3027    int nin2;
3028    double *at2;
3029    double r1;
3030    double r2;
3031    int nout1;
3032    int i;
3033 
3034 /* Check inherited status */
3035    if( !astOK ) return AST__BAD;
3036 
3037 /* Get a pointer to the CmpMap structure. */
3038    map = (AstCmpMap *) this;
3039 
3040 /* Note the current Invert flags of the two component Mappings. */
3041    old_inv1 = astGetInvert( map->map1 );
3042    old_inv2 = astGetInvert( map->map2 );
3043 
3044 /* Temporarily reset them to the values they had when the CmpMap was
3045    created. */
3046    astSetInvert( map->map1, map->invert1 );
3047    astSetInvert( map->map2, map->invert2 );
3048 
3049 /* If the CmpMap itself has been inverted, invert the component Mappings.
3050    Also note the order in which the Mappings should be applied if in series. */
3051    if( !astGetInvert( this ) ) {
3052       c1 = map->map1;
3053       c2 = map->map2;
3054    } else {
3055       c1 = map->map2;
3056       c2 = map->map1;
3057       astInvert( c1 );
3058       astInvert( c2 );
3059    }
3060 
3061 /* First deal with Mappings in series. */
3062    if( map->series ) {
3063 
3064 /* Get the number of inputs to the two component Mappings. */
3065       nin1 = astGetNin( c1 );
3066       nin2 = astGetNin( c2 );
3067 
3068 /* Allocate workspace to hold the result of transforming the supplied "at"
3069    position using the first component. */
3070       at2 = astMalloc( sizeof( double )*(size_t) nin2 );
3071 
3072 /* Transform the supplied "at" position using the first component. */
3073       astTranN( c1, 1, nin1, 1, at, 1, nin2, 1, at2 );
3074 
3075 /* The required rate of change is the sum of the products of the rate of
3076    changes of the two component mappings, summed over all the output axes
3077    of the first componment. */
3078       result = 0.0;
3079       for( i = 0; i < nin2; i++ ) {
3080 
3081 /* Find the rate of change of output "i" of the first component with
3082    respect to input "ax2" at the supplied "at" position. */
3083          r1 = astRate( c1, at, i, ax2 );
3084 
3085 /* Find the rate of change of output "ax1" of the second component with
3086    respect to input "i" at the transformed "at2" position. */
3087          r2 = astRate( c2, at2, ax1, i );
3088 
3089 /* If both are good, increment the ryunning total by the product of the
3090    two rates. Otherwise, break. */
3091          if( r1 != AST__BAD && r2 != AST__BAD ) {
3092             result += r1*r2;
3093          } else {
3094             result = AST__BAD;
3095             break;
3096          }
3097       }
3098 
3099 /* Free the workspace. */
3100       at2 = astFree( at2 );
3101 
3102 /* Now deal with Mappings in parallel. */
3103    } else {
3104 
3105 /* Get the number of inputs and outputs for the lower component Mappings. */
3106       nin1 = astGetNin( map->map1 );
3107       nout1 = astGetNout( map->map1 );
3108 
3109 /* If both input and output relate to the lower component Mappings, use its
3110    astRate method. */
3111       if( ax1 < nout1 && ax2 < nin1 ) {
3112          result = astRate( map->map1, at, ax1, ax2 );
3113 
3114 /* If both input and output relate to the upper component Mappings, use its
3115    astRate method. */
3116       } else if( ax1 >= nout1 && ax2 >= nin1 ) {
3117          result = astRate( map->map2, at + nin1, ax1 - nout1, ax2 - nin1 );
3118 
3119 /* If input and output relate to different component Mappings, return
3120    zero. */
3121       } else {
3122          result = 0.0;
3123       }
3124    }
3125 
3126 /* Reinstate the original Invert flags of the component Mappings .*/
3127    astSetInvert( map->map1, old_inv1 );
3128    astSetInvert( map->map2, old_inv2 );
3129 
3130 /* Return the result. */
3131    return result;
3132 }
3133 
RemoveRegions(AstMapping * this_mapping,int * status)3134 static AstMapping *RemoveRegions( AstMapping *this_mapping, int *status ) {
3135 /*
3136 *  Name:
3137 *     RemoveRegions
3138 
3139 *  Purpose:
3140 *     Remove any Regions from a Mapping.
3141 
3142 *  Type:
3143 *     Private function.
3144 
3145 *  Synopsis:
3146 *     #include "cmpmap.h"
3147 *     AstMapping *RemoveRegions( AstMapping *this, int *status )
3148 
3149 *  Class Membership:
3150 *     CmpMap method (over-rides the astRemoveRegions method inherited
3151 *     from the Mapping class).
3152 
3153 *  Description:
3154 *     This function searches the supplied Mapping (which may be a
3155 *     compound Mapping such as a CmpMap) for any component Mappings
3156 *     that are instances of the AST Region class. It then creates a new
3157 *     Mapping from which all Regions have been removed. If a Region
3158 *     cannot simply be removed (for instance, if it is a component of a
3159 *     parallel CmpMap), then it is replaced with an equivalent UnitMap
3160 *     in the returned Mapping.
3161 *
3162 *     The implementation provided by the CmpMap class invokes the
3163 *     astRemoveRegions method on the two component Mappings, and joins
3164 *     the results together into a new CmpMap.
3165 
3166 *  Parameters:
3167 *     this
3168 *        Pointer to the original Region.
3169 *     status
3170 *        Pointer to the inherited status variable.
3171 
3172 *  Returned Value:
3173 *     A pointer to the modified mapping.
3174 
3175 *  Notes:
3176 *     - A NULL pointer value will be returned if this function is
3177 *     invoked with the AST error status set, or if it should fail for
3178 *     any reason.
3179 */
3180 
3181 /* Local Variables: */
3182    AstCmpMap *new;               /* Pointer to new CmpMap */
3183    AstCmpMap *this;              /* Pointer to CmpMap structure */
3184    AstMapping *newmap1;          /* New first component Mapping */
3185    AstMapping *newmap2;          /* New second component Mapping */
3186    AstMapping *result;           /* Result pointer to return */
3187    int nax;                      /* Number of Frame axes */
3188    int unit1;                    /* Is new first Mapping a UnitMap? */
3189    int unit2;                    /* Is new second Mapping a UnitMap? */
3190 
3191 /* Initialise. */
3192    result = NULL;
3193 
3194 /* Check the global error status. */
3195    if ( !astOK ) return result;
3196 
3197 /* Get a pointer to the CmpMap. */
3198    this = (AstCmpMap *) this_mapping;
3199 
3200 /* Invoke the astRemoveRegions method on the two component Mappings. */
3201    newmap1 = astRemoveRegions( this->map1 );
3202    newmap2 = astRemoveRegions( this->map2 );
3203 
3204 /* If neither component was modified, just return a clone of the supplied
3205    pointer. */
3206    if( this->map1 == newmap1 && this->map2 == newmap2 ) {
3207       result = astClone( this );
3208 
3209 /* Otherwise, we need to create a new Mapping to return. */
3210    } else {
3211 
3212 /* The implementation of the astRemoveRegions method provided by the
3213    Region class returns a Frame rather than a UnitMap. But we need
3214    Mappings here, not Frames. So if either of these new Mappings is
3215    a Frame, replace it with an equivalent UnitMap. Also, get flags
3216    indicating if either Mapping is a UnitMap.*/
3217       if( astIsAFrame( newmap1 ) ) {
3218          nax = astGetNin( newmap1 );
3219          (void) astAnnul( newmap1 );
3220          newmap1 = (AstMapping *) astUnitMap( nax, " ", status );
3221          unit1 = 1;
3222       } else {
3223          unit1 = astIsAUnitMap( newmap1 );
3224       }
3225 
3226       if( astIsAFrame( newmap2 ) ) {
3227          nax = astGetNin( newmap2 );
3228          (void) astAnnul( newmap2 );
3229          newmap2 = (AstMapping *) astUnitMap( nax, " ", status );
3230          unit2 = 1;
3231       } else {
3232          unit2 = astIsAUnitMap( newmap2 );
3233       }
3234 
3235 /* First handle series CmpMaps. */
3236       if( this->series ) {
3237 
3238 /* Otherwise, if the second new Mapping is a UnitMap, return a copy of the
3239    first new Mapping (with the original Invert attribute) since the second
3240    one will have no effect. */
3241          if( unit1 ) {
3242             result = astCopy( newmap2 );
3243             astSetInvert( result, this->invert2 );
3244             if( astGetInvert( this ) ) astInvert( result );
3245 
3246 /* Otherwise, if the second new Mapping is a UnitMap, return a copy of the
3247    first new Mapping (with the original Invert attribute) since the second
3248    one will have no effect. */
3249          } else if( unit2 ) {
3250             result = astCopy( newmap1 );
3251             astSetInvert( result, this->invert1 );
3252             if( astGetInvert( this ) ) astInvert( result );
3253 
3254 /* If neither of the new Mappings is a UnitMap, return a new CmpMap
3255    containing the two new Mappings. We take a deep copy of the supplied
3256    CmpMap and then modify the Mappings os that we retain any extra
3257    information (such as invert flags) in the supplied CmpMap. */
3258          } else {
3259             new = astCopy( this );
3260             (void) astAnnul( new->map1 );
3261             (void) astAnnul( new->map2 );
3262             new->map1 = astClone( newmap1 );
3263             new->map2 = astClone( newmap2 );
3264             result = (AstMapping *) new;
3265          }
3266 
3267 /* Now handle parallel CmpMaps. */
3268       } else {
3269 
3270 /* If both new Mappings are UnitMaps, return an equivalent UnitMap. */
3271          if( unit1 && unit2 ) {
3272             result = (AstMapping *) astUnitMap( astGetNin( newmap1 ) +
3273                                                 astGetNin( newmap2 ), " ",
3274                                                 status );
3275 
3276 /* Otherwise, return a new CmpMap containing the two new Mappings. */
3277          } else {
3278             new = astCopy( this );
3279             (void) astAnnul( new->map1 );
3280             (void) astAnnul( new->map2 );
3281             new->map1 = astClone( newmap1 );
3282             new->map2 = astClone( newmap2 );
3283             result = (AstMapping *) new;
3284          }
3285       }
3286    }
3287 
3288 /* Free resources. */
3289    newmap1 = astAnnul( newmap1 );
3290    newmap2 = astAnnul( newmap2 );
3291 
3292 /* Annul the returned Mapping if an error has occurred. */
3293    if( !astOK ) result = astAnnul( result );
3294 
3295 /* Return the result. */
3296    return result;
3297 }
3298 
Simplify(AstMapping * this_mapping,int * status)3299 static AstMapping *Simplify( AstMapping *this_mapping, int *status ) {
3300 /*
3301 *  Name:
3302 *     Simplify
3303 
3304 *  Purpose:
3305 *     Simplify a Mapping.
3306 
3307 *  Type:
3308 *     Private function.
3309 
3310 *  Synopsis:
3311 *     #include "mapping.h"
3312 *     AstMapping *Simplify( AstMapping *this, int *status )
3313 
3314 *  Class Membership:
3315 *     CmpMap method (over-rides the astSimplify method inherited from
3316 *     the Mapping class).
3317 
3318 *  Description:
3319 *     This function simplifies a CmpMap to eliminate redundant
3320 *     computational steps, or to merge separate steps which can be
3321 *     performed more efficiently in a single operation.
3322 
3323 *  Parameters:
3324 *     this
3325 *        Pointer to the original Mapping.
3326 *     status
3327 *        Pointer to the inherited status variable.
3328 
3329 *  Returned Value:
3330 *     A new pointer to the (possibly simplified) Mapping.
3331 
3332 *  Notes:
3333 *     - A NULL pointer value will be returned if this function is
3334 *     invoked with the AST error status set, or if it should fail for
3335 *     any reason.
3336 */
3337 
3338 /* Local Variables: */
3339    astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
3340    AstCmpMap *this;              /* Pointer to CmpMap structure */
3341    AstMapping **map_list;        /* Mapping array pointer */
3342    AstMapping *map;              /* Pointer to cloned Mapping pointer */
3343    AstMapping *result;           /* Result pointer to return */
3344    AstMapping *tmp;              /* Temporary Mapping pointer */
3345    int *invert_list;             /* Invert array pointer */
3346    int *mlist;                   /* Point to list of modified Mapping indices */
3347    int *nlist;                   /* Point to list of Mapping counts */
3348    int i;                        /* Loop counter for Mappings */
3349    int improved;                 /* Simplification achieved? */
3350    int invert;                   /* Invert attribute value */
3351    int invert_n;                 /* Invert value for final Mapping */
3352    int mlist_len;                /* No. of entries in mlist */
3353    int nlist_len;                /* No. of entries in nlist */
3354    int modified;                 /* Index of first modified Mapping */
3355    int nmap;                     /* Mapping count */
3356    int nominated;                /* Index of nominated Mapping */
3357    int set;                      /* Invert attribute set? */
3358    int set_n;                    /* Invert set for final Mapping? */
3359    int simpler;                  /* Simplification possible? */
3360    int t;                        /* Temporary storage */
3361    int wlen1;                    /* Pattern wavelength for "modified" values */
3362    int wlen2;                    /* Pattern wavelength for "nmap" values */
3363 
3364 /* Initialise. */
3365    result = NULL;
3366 
3367 /* Check the global error status. */
3368    if ( !astOK ) return result;
3369 
3370 /* Get a pointer to the thread specific global data structure. */
3371    astGET_GLOBALS(this_mapping);
3372 
3373 /* It is possible for the astSimplify method to be called recursively from
3374    within astSimplify. It is also possible that the Mapping being
3375    simplified by the current invocation is the same as the Mapping being
3376    simplified by some recursive invocation higher up the call stack. If
3377    this happens we will get into an infinite loop, since we already know
3378    that simplifying the supplied Mapping will involve (eventually) a
3379    recursive call to astSimplify with the same Mapping. To avoid this
3380    looping, we note the Mappings supplied at each depth and first compare
3381    the supplied Mapping with the Mappings which are currently being
3382    simplified higher up the call stack. If the supplied Mapping is
3383    already being simplified at a higher level, then we return immediately
3384    without doing any simplification. Otherwise, we record the supplied
3385    Mapping pointer in a static list so that it is available to subsequent
3386    recursive invocations of this function. First compare the supplied
3387    Mapping with the Mappingsbeing simpliied higher up. Return without
3388    action if a match is found. */
3389    for( i = 0; i < simplify_depth; i++ ) {
3390       if( astEqual( this_mapping, simplify_stackmaps[ i ] ) ) {
3391          return astClone( this_mapping );
3392       }
3393    }
3394 
3395 /* We have further work to do, so increment the recursion depth, extend
3396    the simplify_stackmaps array, and store the new Mapping in it for future use. */
3397    simplify_depth++;
3398    simplify_stackmaps = astGrow( simplify_stackmaps, simplify_depth, sizeof( AstMapping * ) );
3399    if( astOK ) {
3400       simplify_stackmaps[ simplify_depth - 1 ] = astClone( this_mapping );
3401    }
3402 
3403 /* Obtain a pointer to the CmpMap structure. */
3404    this = (AstCmpMap *) this_mapping;
3405 
3406 /* Initialise dynamic arrays of Mapping pointers and associated Invert
3407    flags. */
3408    nmap = 0;
3409    map_list = NULL;
3410    invert_list = NULL;
3411 
3412 /* Decompose the CmpMap into a sequence of Mappings to be applied in
3413    series or parallel, as appropriate, and an associated list of
3414    Invert flags. If any inverted CmpMaps are found in the Mapping, then
3415    we can at least simplify the returned Mapping by swapping and
3416    inverting the components. Set "simpler" to indicate this. */
3417    simpler = astMapList( this_mapping, this->series, astGetInvert( this ), &nmap,
3418                          &map_list, &invert_list );
3419 
3420 /* Initialise pointers to memory used to hold lists of the modified
3421    Mapping index and the number of mappings after each call of
3422    astMapMerge. */
3423    mlist = NULL;
3424    nlist = NULL;
3425 
3426 /* Loop to simplify the sequence until a complete pass through it has
3427    been made without producing any improvement. */
3428    improved = 1;
3429    while ( astOK && improved ) {
3430       improved = 0;
3431 
3432 /* Loop to nominate each Mapping in the sequence in turn. */
3433       nominated = 0;
3434       while ( astOK && ( nominated < nmap ) ) {
3435 
3436 
3437 /* Clone a pointer to the nominated Mapping and attempt to merge it
3438    with its neighbours. Annul the cloned pointer afterwards. */
3439          map = astClone( map_list[ nominated ] );
3440          modified = astMapMerge( map, nominated, this->series,
3441                                  &nmap, &map_list, &invert_list );
3442          map = astAnnul( map );
3443 
3444 /* Move on to nominate the next Mapping in the sequence. */
3445          nominated++;
3446 
3447 /* Note if any simplification occurred above. */
3448          if( modified >= 0 ) {
3449 
3450 /* Append the index of the first modified Mapping in the list and and check
3451    that there is no repreating pattern in the list. If there is, we are
3452    probably in a loop where one mapping class is making a change, and another
3453    is undoing the change. The Looping function returns the "wavelength"
3454    of any pattern found. If a pattern was discovered, we ignore it unless
3455    there is also a pattern in the "nmap" values - the wavelengths of the
3456    two patterns must be related by a integer factor. */
3457             wlen1 = PatternCheck( modified, 1, &mlist, &mlist_len, status );
3458             wlen2 = PatternCheck( nmap, wlen1, &nlist, &nlist_len, status );
3459             if( wlen1 && wlen2 ) {
3460 
3461 /* Ensure wlen2 is larger than or equal to wlen1. */
3462                if( wlen1 > wlen2 ) {
3463                   t = wlen1;
3464                   wlen1 = wlen2;
3465                   wlen2 = t;
3466                }
3467 
3468 /* See if wlen2 is an integer multiple of wlen1. If not, ignore the
3469    patterns. */
3470                if( ( wlen2 % wlen1 ) != 0 ) wlen1 = 0;
3471             }
3472 
3473 /* Ignore the simplication if a repeating pattern is occurring. */
3474             if( wlen1 == 0 ) {
3475                improved = 1;
3476                simpler = 1;
3477 
3478 /* If the simplification resulted in modification of an earlier
3479    Mapping than would normally be considered next, then go back to
3480    consider the modified one first. */
3481                if ( modified < nominated ) nominated = modified;
3482             }
3483          }
3484       }
3485    }
3486 
3487 /* Free resources */
3488    if( mlist ) mlist = astFree( mlist );
3489    if( nlist ) nlist = astFree( nlist );
3490 
3491 /* Construct the output Mapping. */
3492 /* ============================= */
3493 /* If no simplification occurred above, then simply clone a pointer to
3494    the original Mapping. */
3495    if ( astOK ) {
3496       if ( !simpler ) {
3497          result = astClone( this );
3498 
3499 /* Otherwise, we must construct the result from the contents of the
3500    Mapping list. */
3501       } else {
3502 
3503 /* If the simplified Mapping list has only a single element, then the
3504    output Mapping will not be a CmpMap. In this case, we cannot
3505    necessarily set the Invert flag of the Mapping to the value we want
3506    (because we must not modify the Mapping itself. */
3507          if ( nmap == 1 ) {
3508 
3509 /* We must make a copy. Cloning is no good (even if the Mapping already
3510    has the Invert attribute value we want), since we want the returned
3511    Mapping to be independent of the original component Mappings, so that
3512    if user code inverts a component Mapping (via some other pre-existing
3513    pointer), the returned simplified Mapping is not affected. */
3514             result = astCopy( map_list[ 0 ] );
3515 
3516 /* Either clear the copy's Invert attribute, or set it to 1, as
3517    required. */
3518             if ( invert_list[ 0 ] ) {
3519                astSetInvert( result, 1 );
3520             } else {
3521                astClearInvert( result );
3522             }
3523 
3524 /* If the simplified Mapping sequence has more than one element, the
3525    output Mapping will be a CmpMap. In this case, we can set each
3526    individual Mapping element to have the Invert attribute value we
3527    want, so long as we return these attribute values to their original
3528    state again afterwards (once a Mapping is encapsulated inside a
3529    CmpMap, further external changes to its Invert attribute do not
3530    affect the behaviour of the CmpMap). */
3531          } else {
3532 
3533 /* Determine if the Invert attribute for the last Mapping is set, and
3534    obtain its value. */
3535             set_n = astTestInvert( map_list[ nmap - 1 ] );
3536             invert_n = astGetInvert( map_list[ nmap - 1 ] );
3537 
3538 /* Set this attribute to the value we want. */
3539             astSetInvert( map_list[ nmap - 1 ], invert_list[ nmap - 1 ] );
3540 
3541 /* Loop through the Mapping sequence in reverse to merge it into an
3542    equivalent CmpMap. */
3543             for ( i = nmap - 1; i >= 0; i-- ) {
3544 
3545 /* Simply clone the pointer to the last Mapping in the sequence (which
3546    will be encountered first). */
3547               if ( !result ) {
3548                   result = astClone( map_list[ i ] );
3549 
3550 /* For subsequent Mappings, test if the Invert attribute is set and
3551    save its value. */
3552                } else {
3553                   set = astTestInvert( map_list[ i ] );
3554                   invert = astGetInvert( map_list[ i ] );
3555 
3556 /* Set this attribute to the value required. */
3557                   astSetInvert( map_list[ i ], invert_list[ i ] );
3558 
3559 /* Combine the Mapping with the CmpMap formed so far and replace the
3560    result pointer with the new pointer this produces, annulling the
3561    previous pointer. */
3562                   tmp = (AstMapping *) astCmpMap( map_list[ i ], result,
3563                                                   this->series, "", status );
3564                   (void) astAnnul( result );
3565                   result = tmp;
3566 
3567 /* Restore the Invert attribute of the Mapping to its original
3568    state. */
3569                   if ( !set ) {
3570                      astClearInvert( map_list[ i ] );
3571                   } else {
3572                      astSetInvert( map_list[ i ], invert );
3573                   }
3574                }
3575             }
3576 
3577 /* When all the Mappings have been merged into the CmpMap, restore the
3578    state of the Invert attribute for the final Mapping in the
3579    sequence. */
3580             if ( !set_n ) {
3581                astClearInvert( map_list[ nmap - 1  ] );
3582             } else {
3583                astSetInvert( map_list[ nmap - 1 ], invert_n );
3584             }
3585          }
3586       }
3587    }
3588 
3589 /* Clean up. */
3590 /* ========= */
3591 /* Loop to annul all the Mapping pointers in the simplified list. */
3592    for ( i = 0; i < nmap; i++ ) map_list[ i ] = astAnnul( map_list[ i ] );
3593 
3594 /* Free the dynamic arrays. */
3595    map_list = astFree( map_list );
3596    invert_list = astFree( invert_list );
3597 
3598 /* Decrement the recursion depth and free the pointer to the supplied
3599    Mapping currently stored at the end of the simplify_stackmaps array. */
3600    simplify_depth--;
3601    if( astOK ) {
3602       simplify_stackmaps[ simplify_depth ] = astAnnul( simplify_stackmaps[ simplify_depth ] );
3603    }
3604 
3605 /* If we are now at depth zero, free the simplify_stackmaps array. */
3606    if( simplify_depth == 0 ) simplify_stackmaps = astFree( simplify_stackmaps );
3607 
3608 /* If an error occurred, annul the returned Mapping. */
3609    if ( !astOK ) result = astAnnul( result );
3610 
3611 /* Return the result. */
3612    return result;
3613 }
3614 
Transform(AstMapping * this,AstPointSet * in,int forward,AstPointSet * out,int * status)3615 static AstPointSet *Transform( AstMapping *this, AstPointSet *in,
3616                                int forward, AstPointSet *out, int *status ) {
3617 /*
3618 *  Name:
3619 *     Transform
3620 
3621 *  Purpose:
3622 *     Apply a CmpMap to transform a set of points.
3623 
3624 *  Type:
3625 *     Private function.
3626 
3627 *  Synopsis:
3628 *     #include "cmpmap.h"
3629 *     AstPointSet *Transform( AstMapping *this, AstPointSet *in,
3630 *                             int forward, AstPointSet *out, int *status )
3631 
3632 *  Class Membership:
3633 *     CmpMap member function (over-rides the astTransform method inherited
3634 *     from the Mapping class).
3635 
3636 *  Description:
3637 *     This function takes a CmpMap and a set of points encapsulated in a
3638 *     PointSet and transforms the points so as to apply the required Mapping.
3639 *     This implies applying each of the CmpMap's component Mappings in turn,
3640 *     either in series or in parallel.
3641 
3642 *  Parameters:
3643 *     this
3644 *        Pointer to the CmpMap.
3645 *     in
3646 *        Pointer to the PointSet associated with the input coordinate values.
3647 *     forward
3648 *        A non-zero value indicates that the forward coordinate transformation
3649 *        should be applied, while a zero value requests the inverse
3650 *        transformation.
3651 *     out
3652 *        Pointer to a PointSet which will hold the transformed (output)
3653 *        coordinate values. A NULL value may also be given, in which case a
3654 *        new PointSet will be created by this function.
3655 *     status
3656 *        Pointer to the inherited status variable.
3657 
3658 *  Returned Value:
3659 *     Pointer to the output (possibly new) PointSet.
3660 
3661 *  Notes:
3662 *     -  A null pointer will be returned if this function is invoked with the
3663 *     global error status set, or if it should fail for any reason.
3664 *     -  The number of coordinate values per point in the input PointSet must
3665 *     match the number of coordinates for the CmpMap being applied.
3666 *     -  If an output PointSet is supplied, it must have space for sufficient
3667 *     number of points and coordinate values per point to accommodate the
3668 *     result. Any excess space will be ignored.
3669 */
3670 
3671 /* Local Variables: */
3672    AstCmpMap *map;               /* Pointer to CmpMap to be applied */
3673    AstPointSet *result;          /* Pointer to output PointSet */
3674    AstPointSet *temp1;           /* Pointer to temporary PointSet */
3675    AstPointSet *temp2;           /* Pointer to temporary PointSet */
3676    AstPointSet *temp;            /* Pointer to temporary PointSet */
3677    int forward1;                 /* Use forward direction for Mapping 1? */
3678    int forward2;                 /* Use forward direction for Mapping 2? */
3679    int ipoint1;                  /* Index of first point in batch */
3680    int ipoint2;                  /* Index of last point in batch */
3681    int nin1;                     /* No. input coordinates for Mapping 1 */
3682    int nin2;                     /* No. input coordinates for Mapping 2 */
3683    int nin;                      /* No. input coordinates supplied */
3684    int nout1;                    /* No. output coordinates for Mapping 1 */
3685    int nout2;                    /* No. output coordinates for Mapping 2 */
3686    int nout;                     /* No. output coordinates supplied */
3687    int np;                       /* Number of points in batch */
3688    int npoint;                   /* Number of points to be transformed */
3689 
3690 /* Local Constants: */
3691    const int nbatch = 2048;      /* Maximum points in a batch */
3692 
3693 /* Check the global error status. */
3694    if ( !astOK ) return NULL;
3695 
3696 /* Obtain a pointer to the CmpMap. */
3697    map = (AstCmpMap *) this;
3698 
3699 /* Apply the parent Mapping using the stored pointer to the Transform member
3700    function inherited from the parent Mapping class. This function validates
3701    all arguments and generates an output PointSet if necessary, but does not
3702    actually transform any coordinate values. */
3703    result = (*parent_transform)( this, in, forward, out, status );
3704 
3705 /* We now extend the parent astTransform method by applying the component
3706    Mappings of the CmpMap to generate the output coordinate values. */
3707 
3708 /* Determine whether to apply the forward or inverse Mapping, according to the
3709    direction specified and whether the Mapping has been inverted. */
3710    if ( astGetInvert( map ) ) forward = !forward;
3711 
3712 /* Check if either component Mapping's inversion flag has changed since it was
3713    used to construct the CmpMap. Set a "forward" flag for each Mapping to
3714    change the direction we will use, to compensate if necessary. (Such changes
3715    may have occurred if other pointers to the component Mappings are in
3716    circulation). */
3717    forward1 = forward;
3718    forward2 = forward;
3719    if ( map->invert1 != astGetInvert( map->map1 ) ) forward1 = !forward1;
3720    if ( map->invert2 != astGetInvert( map->map2 ) ) forward2 = !forward2;
3721 
3722 /* Determine the number of points being transformed. */
3723    npoint = astGetNpoint( in );
3724 
3725 /* Mappings in series. */
3726 /* ------------------- */
3727 /* If required, use the two component Mappings in series. To do this, we must
3728    apply one Mapping followed by the other, which means storing an intermediate
3729    result. Since this function may be invoked recursively and have to store an
3730    intermediate result on each occasion, the memory required may become
3731    excessive when transforming large numbers of points. To overcome this, we
3732    split the points up into smaller batches. */
3733    if ( astOK ) {
3734       if ( map->series ) {
3735 
3736 /* Obtain the numbers of input and output coordinates. */
3737          nin = astGetNcoord( in );
3738          nout = astGetNcoord( result );
3739 
3740 /* Loop to process all the points in batches, of maximum size nbatch points. */
3741          for ( ipoint1 = 0; ipoint1 < npoint; ipoint1 += nbatch ) {
3742 
3743 /* Calculate the index of the final point in the batch and deduce the number of
3744    points (np) to be processed in this batch. */
3745             ipoint2 = ipoint1 + nbatch - 1;
3746             if ( ipoint2 > npoint - 1 ) ipoint2 = npoint - 1;
3747             np = ipoint2 - ipoint1 + 1;
3748 
3749 /* Create temporary PointSets to describe the input and output points for this
3750    batch. */
3751             temp1 = astPointSet( np, nin, "", status );
3752             temp2 = astPointSet( np, nout, "", status );
3753 
3754 /* Associate the required subsets of the input and output coordinates with the
3755    two PointSets. */
3756             astSetSubPoints( in, ipoint1, 0, temp1 );
3757             astSetSubPoints( result, ipoint1, 0, temp2 );
3758 
3759 /* Apply the two Mappings in sequence and in the required order and direction.
3760    Store the intermediate result in a temporary PointSet (temp) which is
3761    created by the first Mapping applied. */
3762             if ( forward ) {
3763                temp = astTransform( map->map1, temp1, forward1, NULL );
3764                (void) astTransform( map->map2, temp, forward2, temp2 );
3765             } else {
3766                temp = astTransform( map->map2, temp1, forward2, NULL );
3767                (void) astTransform( map->map1, temp, forward1, temp2 );
3768             }
3769 
3770 /* Delete the temporary PointSets after processing each batch of points. */
3771             temp = astDelete( temp );
3772             temp1 = astDelete( temp1 );
3773             temp2 = astDelete( temp2 );
3774 
3775 /* Quit processing batches if an error occurs. */
3776             if ( !astOK ) break;
3777          }
3778 
3779 /* Mappings in parallel. */
3780 /* --------------------- */
3781 /* If required, use the two component Mappings in parallel. Since we do not
3782    need to allocate any memory to hold intermediate coordinate values here,
3783    there is no need to process the points in batches. */
3784       } else {
3785 
3786 /* Get the effective number of input and output coordinates per point for each
3787    Mapping (taking account of the direction in which each will be used to
3788    transform points). */
3789          nin1 = forward1 ? astGetNin( map->map1 ) : astGetNout( map->map1 );
3790          nout1 = forward1 ? astGetNout( map->map1 ) : astGetNin( map->map1 );
3791          nin2 = forward2 ? astGetNin( map->map2 ) : astGetNout( map->map2 );
3792          nout2 = forward2 ? astGetNout( map->map2 ) : astGetNin( map->map2 );
3793 
3794 /* Create temporary PointSets to describe the input and output coordinates for
3795    the first Mapping. */
3796          temp1 = astPointSet( npoint, nin1, "", status );
3797          temp2 = astPointSet( npoint, nout1, "", status );
3798 
3799 /* Associate the required subsets of the input and output coordinates with
3800    these PointSets. */
3801          astSetSubPoints( in, 0, 0, temp1 );
3802          astSetSubPoints( result, 0, 0, temp2 );
3803 
3804 /* Use the astTransform method to apply the coordinate transformation described
3805    by the first Mapping. */
3806          (void) astTransform( map->map1, temp1, forward1, temp2 );
3807 
3808 /* Delete the temporary PointSets. */
3809          temp1 = astDelete( temp1 );
3810          temp2 = astDelete( temp2 );
3811 
3812 /* Create a new pair of temporary PointSets to describe the input and output
3813    coordinates for the second Mapping, and associate the required subsets of
3814    the input and output coordinates with these PointSets. */
3815          temp1 = astPointSet( npoint, nin2, "", status );
3816          temp2 = astPointSet( npoint, nout2, "", status );
3817          astSetSubPoints( in, 0, nin1, temp1 );
3818          astSetSubPoints( result, 0, nout1, temp2 );
3819 
3820 /* Apply the coordinate transformation described by the second Mapping. */
3821          (void) astTransform( map->map2, temp1, forward2, temp2 );
3822 
3823 /* Delete the two temporary PointSets. */
3824          temp1 = astDelete( temp1 );
3825          temp2 = astDelete( temp2 );
3826       }
3827    }
3828 
3829 /* If an error occurred, clean up by deleting the output PointSet (if
3830    allocated by this function) and setting a NULL result pointer. */
3831    if ( !astOK ) {
3832       if ( !out ) result = astDelete( result );
3833       result = NULL;
3834    }
3835 
3836 /* Return a pointer to the output PointSet. */
3837    return result;
3838 }
3839 
3840 /* Copy constructor. */
3841 /* ----------------- */
Copy(const AstObject * objin,AstObject * objout,int * status)3842 static void Copy( const AstObject *objin, AstObject *objout, int *status ) {
3843 /*
3844 *  Name:
3845 *     Copy
3846 
3847 *  Purpose:
3848 *     Copy constructor for CmpMap objects.
3849 
3850 *  Type:
3851 *     Private function.
3852 
3853 *  Synopsis:
3854 *     void Copy( const AstObject *objin, AstObject *objout, int *status )
3855 
3856 *  Description:
3857 *     This function implements the copy constructor for CmpMap objects.
3858 
3859 *  Parameters:
3860 *     objin
3861 *        Pointer to the object to be copied.
3862 *     objout
3863 *        Pointer to the object being constructed.
3864 *     status
3865 *        Pointer to the inherited status variable.
3866 
3867 *  Returned Value:
3868 *     void
3869 
3870 *  Notes:
3871 *     -  This constructor makes a deep copy, including a copy of the component
3872 *     Mappings within the CmpMap.
3873 */
3874 
3875 /* Local Variables: */
3876    AstCmpMap *in;                /* Pointer to input CmpMap */
3877    AstCmpMap *out;               /* Pointer to output CmpMap */
3878 
3879 /* Check the global error status. */
3880    if ( !astOK ) return;
3881 
3882 /* Obtain pointers to the input and output CmpMaps. */
3883    in = (AstCmpMap *) objin;
3884    out = (AstCmpMap *) objout;
3885 
3886 /* For safety, start by clearing any references to the input component
3887    Mappings from the output CmpMap. */
3888    out->map1 = NULL;
3889    out->map2 = NULL;
3890 
3891 /* Make copies of these Mappings and store pointers to them in the output
3892    CmpMap structure. */
3893    out->map1 = astCopy( in->map1 );
3894    out->map2 = astCopy( in->map2 );
3895 }
3896 
3897 /* Destructor. */
3898 /* ----------- */
Delete(AstObject * obj,int * status)3899 static void Delete( AstObject *obj, int *status ) {
3900 /*
3901 *  Name:
3902 *     Delete
3903 
3904 *  Purpose:
3905 *     Destructor for CmpMap objects.
3906 
3907 *  Type:
3908 *     Private function.
3909 
3910 *  Synopsis:
3911 *     void Delete( AstObject *obj, int *status )
3912 
3913 *  Description:
3914 *     This function implements the destructor for CmpMap objects.
3915 
3916 *  Parameters:
3917 *     obj
3918 *        Pointer to the object to be deleted.
3919 *     status
3920 *        Pointer to the inherited status variable.
3921 
3922 *  Returned Value:
3923 *     void
3924 
3925 *  Notes:
3926 *     This function attempts to execute even if the global error status is
3927 *     set.
3928 */
3929 
3930 /* Local Variables: */
3931    AstCmpMap *this;              /* Pointer to CmpMap */
3932 
3933 /* Obtain a pointer to the CmpMap structure. */
3934    this = (AstCmpMap *) obj;
3935 
3936 /* Annul the pointers to the component Mappings. */
3937    this->map1 = astAnnul( this->map1 );
3938    this->map2 = astAnnul( this->map2 );
3939 
3940 /* Clear the remaining CmpMap variables. */
3941    this->invert1 = 0;
3942    this->invert2 = 0;
3943    this->series = 0;
3944 }
3945 
3946 /* Dump function. */
3947 /* -------------- */
Dump(AstObject * this_object,AstChannel * channel,int * status)3948 static void Dump( AstObject *this_object, AstChannel *channel, int *status ) {
3949 /*
3950 *  Name:
3951 *     Dump
3952 
3953 *  Purpose:
3954 *     Dump function for CmpMap objects.
3955 
3956 *  Type:
3957 *     Private function.
3958 
3959 *  Synopsis:
3960 *     void Dump( AstObject *this, AstChannel *channel, int *status )
3961 
3962 *  Description:
3963 *     This function implements the Dump function which writes out data
3964 *     for the CmpMap class to an output Channel.
3965 
3966 *  Parameters:
3967 *     this
3968 *        Pointer to the CmpMap whose data are being written.
3969 *     channel
3970 *        Pointer to the Channel to which the data are being written.
3971 *     status
3972 *        Pointer to the inherited status variable.
3973 */
3974 
3975 /* Local Variables: */
3976    AstCmpMap *this;              /* Pointer to the CmpMap structure */
3977    int ival;                     /* Integer value */
3978    int set;                      /* Attribute value set? */
3979 
3980 /* Check the global error status. */
3981    if ( !astOK ) return;
3982 
3983 /* Obtain a pointer to the CmpMap structure. */
3984    this = (AstCmpMap *) this_object;
3985 
3986 /* Write out values representing the instance variables for the CmpMap
3987    class.  Accompany these with appropriate comment strings, possibly
3988    depending on the values being written.*/
3989 
3990 /* In the case of attributes, we first use the appropriate (private)
3991    Test...  member function to see if they are set. If so, we then use
3992    the (private) Get... function to obtain the value to be written
3993    out.
3994 
3995    For attributes which are not set, we use the astGet... method to
3996    obtain the value instead. This will supply a default value
3997    (possibly provided by a derived class which over-rides this method)
3998    which is more useful to a human reader as it corresponds to the
3999    actual default attribute value.  Since "set" will be zero, these
4000    values are for information only and will not be read back. */
4001 
4002 /* Series. */
4003 /* ------- */
4004    ival = this->series;
4005    set = ( ival == 0 );
4006    astWriteInt( channel, "Series", set, 0, ival,
4007                 ival ? "Component Mappings applied in series" :
4008                        "Component Mappings applied in parallel" );
4009 
4010 /* First Invert flag. */
4011 /* ------------------ */
4012    ival = this->invert1;
4013    set = ( ival != 0 );
4014    astWriteInt( channel, "InvA", set, 0, ival,
4015                 ival ? "First Mapping used in inverse direction" :
4016                        "First Mapping used in forward direction" );
4017 
4018 /* Second Invert flag. */
4019 /* ------------------- */
4020    ival = this->invert2;
4021    set = ( ival != 0 );
4022    astWriteInt( channel, "InvB", set, 0, ival,
4023                 ival ? "Second Mapping used in inverse direction" :
4024                        "Second Mapping used in forward direction" );
4025 
4026 /* First Mapping. */
4027 /* -------------- */
4028    astWriteObject( channel, "MapA", 1, 1, this->map1,
4029                    "First component Mapping" );
4030 
4031 /* Second Mapping. */
4032 /* --------------- */
4033    astWriteObject( channel, "MapB", 1, 1, this->map2,
4034                    "Second component Mapping" );
4035 }
4036 
4037 /* Standard class functions. */
4038 /* ========================= */
4039 /* Implement the astIsACmpMap and astCheckCmpMap functions using the
4040    macros defined for this purpose in the "object.h" header file. */
astMAKE_ISA(CmpMap,Mapping)4041 astMAKE_ISA(CmpMap,Mapping)
4042 astMAKE_CHECK(CmpMap)
4043 
4044 AstCmpMap *astCmpMap_( void *map1_void, void *map2_void, int series,
4045                        const char *options, int *status, ...) {
4046 /*
4047 *+
4048 *  Name:
4049 *     astCmpMap
4050 
4051 *  Purpose:
4052 *     Create a CmpMap.
4053 
4054 *  Type:
4055 *     Protected function.
4056 
4057 *  Synopsis:
4058 *     #include "cmpmap.h"
4059 *     AstCmpMap *astCmpMap( AstMapping *map1, AstMapping *map2, int series,
4060 *                           const char *options, ... )
4061 
4062 *  Class Membership:
4063 *     CmpMap constructor.
4064 
4065 *  Description:
4066 *     This function creates a new CmpMap and optionally initialises its
4067 *     attributes.
4068 
4069 *  Parameters:
4070 *     map1
4071 *        Pointer to the first Mapping.
4072 *     map2
4073 *        Pointer to the second Mapping.
4074 *     series
4075 *        If a non-zero value is given, the two Mappings will be connected
4076 *        together in series. A zero value requests that they be connected in
4077 *        parallel.
4078 *     options
4079 *        Pointer to a null terminated string containing an optional
4080 *        comma-separated list of attribute assignments to be used for
4081 *        initialising the new CmpMap. The syntax used is the same as for the
4082 *        astSet method and may include "printf" format specifiers identified
4083 *        by "%" symbols in the normal way.
4084 *     ...
4085 *        If the "options" string contains "%" format specifiers, then an
4086 *        optional list of arguments may follow it in order to supply values to
4087 *        be substituted for these specifiers. The rules for supplying these
4088 *        are identical to those for the astSet method (and for the C "printf"
4089 *        function).
4090 
4091 *  Returned Value:
4092 *     A pointer to the new CmpMap.
4093 
4094 *  Notes:
4095 *     - A null pointer will be returned if this function is invoked
4096 *     with the global error status set, or if it should fail for any
4097 *     reason.
4098 *-
4099 
4100 *  Implementation Notes:
4101 *     - This function implements the basic CmpMap constructor which is
4102 *     available via the protected interface to the CmpMap class.  A
4103 *     public interface is provided by the astCmpMapId_ function.
4104 *     - Because this function has a variable argument list, it is
4105 *     invoked by a macro that evaluates to a function pointer (not a
4106 *     function invocation) and no checking or casting of arguments is
4107 *     performed before the function is invoked. Because of this, the
4108 *     "map1" and "map2" parameters are of type (void *) and are
4109 *     converted and validated within the function itself.
4110 */
4111 
4112 /* Local Variables: */
4113    astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
4114    AstCmpMap *new;               /* Pointer to new CmpMap */
4115    AstMapping *map1;             /* Pointer to first Mapping structure */
4116    AstMapping *map2;             /* Pointer to second Mapping structure */
4117    va_list args;                 /* Variable argument list */
4118 
4119 /* Initialise. */
4120    new = NULL;
4121 
4122 /* Get a pointer to the thread specific global data structure. */
4123    astGET_GLOBALS(NULL);
4124 
4125 /* Check the global status. */
4126    if ( !astOK ) return new;
4127 
4128 /* Obtain and validate pointers to the Mapping structures provided. */
4129    map1 = astCheckMapping( map1_void );
4130    map2 = astCheckMapping( map2_void );
4131    if ( astOK ) {
4132 
4133 /* Initialise the CmpMap, allocating memory and initialising the
4134    virtual function table as well if necessary. */
4135       new = astInitCmpMap( NULL, sizeof( AstCmpMap ), !class_init, &class_vtab,
4136                            "CmpMap", map1, map2, series );
4137 
4138 /* If successful, note that the virtual function table has been
4139    initialised. */
4140       if ( astOK ) {
4141          class_init = 1;
4142 
4143 /* Obtain the variable argument list and pass it along with the
4144    options string to the astVSet method to initialise the new CmpMap's
4145    attributes. */
4146          va_start( args, status );
4147          astVSet( new, options, NULL, args );
4148          va_end( args );
4149 
4150 /* If an error occurred, clean up by deleting the new object. */
4151          if ( !astOK ) new = astDelete( new );
4152       }
4153    }
4154 
4155 /* Return a pointer to the new CmpMap. */
4156    return new;
4157 }
4158 
astCmpMapId_(void * map1_void,void * map2_void,int series,const char * options,...)4159 AstCmpMap *astCmpMapId_( void *map1_void, void *map2_void, int series,
4160                          const char *options, ... ) {
4161 /*
4162 *++
4163 *  Name:
4164 c     astCmpMap
4165 f     AST_CMPMAP
4166 
4167 *  Purpose:
4168 *     Create a CmpMap.
4169 
4170 *  Type:
4171 *     Public function.
4172 
4173 *  Synopsis:
4174 c     #include "cmpmap.h"
4175 c     AstCmpMap *astCmpMap( AstMapping *map1, AstMapping *map2, int series,
4176 c                           const char *options, ... )
4177 f     RESULT = AST_CMPMAP( MAP1, MAP2, SERIES, OPTIONS, STATUS )
4178 
4179 *  Class Membership:
4180 *     CmpMap constructor.
4181 
4182 *  Description:
4183 *     This function creates a new CmpMap and optionally initialises
4184 *     its attributes.
4185 *
4186 *     A CmpMap is a compound Mapping which allows two component
4187 *     Mappings (of any class) to be connected together to form a more
4188 *     complex Mapping. This connection may either be "in series"
4189 *     (where the first Mapping is used to transform the coordinates of
4190 *     each point and the second mapping is then applied to the
4191 *     result), or "in parallel" (where one Mapping transforms the
4192 *     earlier coordinates for each point and the second Mapping
4193 *     simultaneously transforms the later coordinates).
4194 *
4195 *     Since a CmpMap is itself a Mapping, it can be used as a
4196 *     component in forming further CmpMaps. Mappings of arbitrary
4197 *     complexity may be built from simple individual Mappings in this
4198 *     way.
4199 
4200 *  Parameters:
4201 c     map1
4202 f     MAP1 = INTEGER (Given)
4203 *        Pointer to the first component Mapping.
4204 c     map2
4205 f     MAP2 = INTEGER (Given)
4206 *        Pointer to the second component Mapping.
4207 c     series
4208 f     SERIES = LOGICAL (Given)
4209 c        If a non-zero value is given for this parameter, the two
4210 c        component Mappings will be connected in series. A zero
4211 c        value requests that they are connected in parallel.
4212 f        If a .TRUE. value is given for this argument, the two
4213 f        component Mappings will be connected in series. A
4214 f        .FALSE. value requests that they are connected in parallel.
4215 c     options
4216 f     OPTIONS = CHARACTER * ( * ) (Given)
4217 c        Pointer to a null-terminated string containing an optional
4218 c        comma-separated list of attribute assignments to be used for
4219 c        initialising the new CmpMap. The syntax used is identical to
4220 c        that for the astSet function and may include "printf" format
4221 c        specifiers identified by "%" symbols in the normal way.
4222 f        A character string containing an optional comma-separated
4223 f        list of attribute assignments to be used for initialising the
4224 f        new CmpMap. The syntax used is identical to that for the
4225 f        AST_SET routine.
4226 c     ...
4227 c        If the "options" string contains "%" format specifiers, then
4228 c        an optional list of additional arguments may follow it in
4229 c        order to supply values to be substituted for these
4230 c        specifiers. The rules for supplying these are identical to
4231 c        those for the astSet function (and for the C "printf"
4232 c        function).
4233 f     STATUS = INTEGER (Given and Returned)
4234 f        The global status.
4235 
4236 *  Returned Value:
4237 c     astCmpMap()
4238 f     AST_CMPMAP = INTEGER
4239 *        A pointer to the new CmpMap.
4240 
4241 *  Notes:
4242 *     - If the component Mappings are connected in series, then using
4243 *     the resulting CmpMap to transform coordinates will cause the
4244 *     first Mapping to be applied, followed by the second Mapping. If
4245 *     the inverse CmpMap transformation is requested, the two
4246 *     component Mappings will be applied in both the reverse order and
4247 *     the reverse direction.
4248 *     - When connecting two component Mappings in series, the number
4249 *     of output coordinates generated by the first Mapping (its Nout
4250 *     attribute) must equal the number of input coordinates accepted
4251 *     by the second Mapping (its Nin attribute).
4252 *     - If the component Mappings of a CmpMap are connected in
4253 *     parallel, then the first Mapping will be used to transform the
4254 *     earlier input coordinates for each point (and to produce the
4255 *     earlier output coordinates) and the second Mapping will be used
4256 *     simultaneously to transform the remaining input coordinates (to
4257 *     produce the remaining output coordinates for each point). If the
4258 *     inverse transformation is requested, each Mapping will still be
4259 *     applied to the same coordinates, but in the reverse direction.
4260 *     - When connecting two component Mappings in parallel, there is
4261 *     no restriction on the number of input and output coordinates for
4262 *     each Mapping.
4263 c     - Note that the component Mappings supplied are not copied by
4264 c     astCmpMap (the new CmpMap simply retains a reference to
4265 c     them). They may continue to be used for other purposes, but
4266 c     should not be deleted. If a CmpMap containing a copy of its
4267 c     component Mappings is required, then a copy of the CmpMap should
4268 c     be made using astCopy.
4269 f     - Note that the component Mappings supplied are not copied by
4270 f     AST_CMPMAP (the new CmpMap simply retains a reference to
4271 f     them). They may continue to be used for other purposes, but
4272 f     should not be deleted. If a CmpMap containing a copy of its
4273 f     component Mappings is required, then a copy of the CmpMap should
4274 f     be made using AST_COPY.
4275 *     - A null Object pointer (AST__NULL) will be returned if this
4276 c     function is invoked with the AST error status set, or if it
4277 f     function is invoked with STATUS set to an error value, or if it
4278 *     should fail for any reason.
4279 *--
4280 
4281 *  Implementation Notes:
4282 *     - This function implements the external (public) interface to
4283 *     the astCmpMap constructor function. It returns an ID value
4284 *     (instead of a true C pointer) to external users, and must be
4285 *     provided because astCmpMap_ has a variable argument list which
4286 *     cannot be encapsulated in a macro (where this conversion would
4287 *     otherwise occur).
4288 *     - Because no checking or casting of arguments is performed
4289 *     before the function is invoked, the "map1" and "map2" parameters
4290 *     are of type (void *) and are converted from an ID value to a
4291 *     pointer and validated within the function itself.
4292 *     - The variable argument list also prevents this function from
4293 *     invoking astCmpMap_ directly, so it must be a re-implementation
4294 *     of it in all respects, except for the conversions between IDs
4295 *     and pointers on input/output of Objects.
4296 */
4297 
4298 /* Local Variables: */
4299    astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
4300    AstCmpMap *new;               /* Pointer to new CmpMap */
4301    AstMapping *map1;             /* Pointer to first Mapping structure */
4302    AstMapping *map2;             /* Pointer to second Mapping structure */
4303    va_list args;                 /* Variable argument list */
4304 
4305    int *status;                  /* Pointer to inherited status value */
4306 
4307 /* Get a pointer to the thread specific global data structure. */
4308    astGET_GLOBALS(NULL);
4309 
4310 /* Initialise. */
4311    new = NULL;
4312 
4313 /* Get a pointer to the inherited status value. */
4314    status = astGetStatusPtr;
4315 
4316 /* Check the global status. */
4317    if ( !astOK ) return new;
4318 
4319 /* Obtain the Mapping pointers from the ID's supplied and validate the
4320    pointers to ensure they identify valid Mappings. */
4321    map1 = astVerifyMapping( astMakePointer( map1_void ) );
4322    map2 = astVerifyMapping( astMakePointer( map2_void ) );
4323    if ( astOK ) {
4324 
4325 /* Initialise the CmpMap, allocating memory and initialising the
4326    virtual function table as well if necessary. */
4327       new = astInitCmpMap( NULL, sizeof( AstCmpMap ), !class_init, &class_vtab,
4328                            "CmpMap", map1, map2, series );
4329 
4330 /* If successful, note that the virtual function table has been initialised. */
4331       if ( astOK ) {
4332          class_init = 1;
4333 
4334 /* Obtain the variable argument list and pass it along with the
4335    options string to the astVSet method to initialise the new CmpMap's
4336    attributes. */
4337          va_start( args, options );
4338          astVSet( new, options, NULL, args );
4339          va_end( args );
4340 
4341 /* If an error occurred, clean up by deleting the new object. */
4342          if ( !astOK ) new = astDelete( new );
4343       }
4344    }
4345 
4346 /* Return an ID value for the new CmpMap. */
4347    return astMakeId( new );
4348 }
4349 
astInitCmpMap_(void * mem,size_t size,int init,AstCmpMapVtab * vtab,const char * name,AstMapping * map1,AstMapping * map2,int series,int * status)4350 AstCmpMap *astInitCmpMap_( void *mem, size_t size, int init,
4351                            AstCmpMapVtab *vtab, const char *name,
4352                            AstMapping *map1, AstMapping *map2, int series, int *status ) {
4353 /*
4354 *+
4355 *  Name:
4356 *     astInitCmpMap
4357 
4358 *  Purpose:
4359 *     Initialise a CmpMap.
4360 
4361 *  Type:
4362 *     Protected function.
4363 
4364 *  Synopsis:
4365 *     #include "cmpmap.h"
4366 *     AstCmpMap *astInitCmpMap( void *mem, size_t size, int init,
4367 *                               AstCmpMapVtab *vtab, const char *name,
4368 *                               AstMapping *map1, AstMapping *map2,
4369 *                               int series )
4370 
4371 *  Class Membership:
4372 *     CmpMap initialiser.
4373 
4374 *  Description:
4375 *     This function is provided for use by class implementations to initialise
4376 *     a new CmpMap object. It allocates memory (if necessary) to
4377 *     accommodate the CmpMap plus any additional data associated with the
4378 *     derived class. It then initialises a CmpMap structure at the start
4379 *     of this memory. If the "init" flag is set, it also initialises the
4380 *     contents of a virtual function table for a CmpMap at the start of
4381 *     the memory passed via the "vtab" parameter.
4382 
4383 *  Parameters:
4384 *     mem
4385 *        A pointer to the memory in which the CmpMap is to be initialised.
4386 *        This must be of sufficient size to accommodate the CmpMap data
4387 *        (sizeof(CmpMap)) plus any data used by the derived class. If a
4388 *        value of NULL is given, this function will allocate the memory itself
4389 *        using the "size" parameter to determine its size.
4390 *     size
4391 *        The amount of memory used by the CmpMap (plus derived class
4392 *        data). This will be used to allocate memory if a value of NULL is
4393 *        given for the "mem" parameter. This value is also stored in the
4394 *        CmpMap structure, so a valid value must be supplied even if not
4395 *        required for allocating memory.
4396 *     init
4397 *        A logical flag indicating if the CmpMap's virtual function table
4398 *        is to be initialised. If this value is non-zero, the virtual function
4399 *        table will be initialised by this function.
4400 *     vtab
4401 *        Pointer to the start of the virtual function table to be associated
4402 *        with the new CmpMap.
4403 *     name
4404 *        Pointer to a constant null-terminated character string which contains
4405 *        the name of the class to which the new object belongs (it is this
4406 *        pointer value that will subsequently be returned by the Object
4407 *        astClass function).
4408 *     map1
4409 *        Pointer to the first Mapping.
4410 *     map2
4411 *        Pointer to the second Mapping.
4412 *     series
4413 *        If a non-zero value is given, the two Mappings will be connected
4414 *        together in series. A zero value requests that they be connected in
4415 *        parallel.
4416 
4417 *  Returned Value:
4418 *     A pointer to the new CmpMap.
4419 
4420 *  Notes:
4421 *     -  A null pointer will be returned if this function is invoked with the
4422 *     global error status set, or if it should fail for any reason.
4423 *-
4424 */
4425 
4426 /* Local Variables: */
4427    AstCmpMap *new;               /* Pointer to new CmpMap */
4428    int map_f;                    /* Forward transformation defined? */
4429    int map_i;                    /* Inverse transformation defined? */
4430    int nin2;                     /* No. input coordinates for Mapping 2 */
4431    int nin;                      /* No. input coordinates for CmpMap */
4432    int nout1;                    /* No. output coordinates for Mapping 1 */
4433    int nout;                     /* No. output coordinates for CmpMap */
4434 
4435 /* Check the global status. */
4436    if ( !astOK ) return NULL;
4437 
4438 /* If necessary, initialise the virtual function table. */
4439    if ( init ) astInitCmpMapVtab( vtab, name );
4440 
4441 /* Initialise. */
4442    new = NULL;
4443 
4444 /* Determine in which directions each component Mapping is able to transform
4445    coordinates. Combine these results to obtain a result for the overall
4446    CmpMap. */
4447    map_f = astGetTranForward( map1 ) && astGetTranForward( map2 );
4448    map_i = astGetTranInverse( map1 ) && astGetTranInverse( map2 );
4449    if ( astOK ) {
4450 
4451 /* If connecting the Mappings in series, check that the number of coordinates
4452    are compatible and report an error if they are not. */
4453       if ( series ) {
4454          nout1 = astGetNout( map1 );
4455          nin2 = astGetNin( map2 );
4456          if ( astOK && ( nout1 != nin2 ) ) {
4457             astError( AST__INNCO, "astInitCmpMap(%s): The number of output "
4458                       "coordinates per point (%d) for the first Mapping "
4459                       "supplied does not match the number of input "
4460                       "coordinates (%d) for the second Mapping.", status, name, nout1,
4461                       nin2 );
4462          }
4463       }
4464    }
4465 
4466 /* If OK, determine the total number of input and output coordinates per point
4467    for the CmpMap. */
4468    if ( astOK ) {
4469       if ( series ) {
4470          nin = astGetNin( map1 );
4471          nout = astGetNout( map2 );
4472       } else {
4473          nin = astGetNin( map1 ) + astGetNin( map2 );
4474          nout = astGetNout( map1 ) + astGetNout( map2 );
4475       }
4476 
4477    } else {
4478       nin = 0;
4479       nout = 0;
4480    }
4481 
4482 /* Initialise a Mapping structure (the parent class) as the first component
4483    within the CmpMap structure, allocating memory if necessary. Specify
4484    the number of input and output coordinates and in which directions the
4485    Mapping should be defined. */
4486    if ( astOK ) {
4487       new = (AstCmpMap *) astInitMapping( mem, size, 0,
4488                                           (AstMappingVtab *) vtab, name,
4489                                           nin, nout, map_f, map_i );
4490 
4491       if ( astOK ) {
4492 
4493 /* Initialise the CmpMap data. */
4494 /* --------------------------- */
4495 /* Store pointers to the component Mappings. Extract Mappings if
4496    FrameSets are provided. */
4497          if( astIsAFrameSet( map1 ) ) {
4498             new->map1 = astGetMapping( (AstFrameSet *) map1, AST__BASE,
4499                                        AST__CURRENT );
4500          } else {
4501             new->map1 = astClone( map1 );
4502          }
4503 
4504          if( astIsAFrameSet( map2 ) ) {
4505             new->map2 = astGetMapping( (AstFrameSet *) map2, AST__BASE,
4506                                        AST__CURRENT );
4507          } else {
4508             new->map2 = astClone( map2 );
4509          }
4510 
4511 
4512 /* Save the initial values of the inversion flags for these Mappings. */
4513          new->invert1 = astGetInvert( new->map1 );
4514          new->invert2 = astGetInvert( new->map2 );
4515 
4516 /* Note whether the Mappings are joined in series (instead of in parallel),
4517    constraining this flag to be 0 or 1. */
4518          new->series = ( series != 0 );
4519 
4520 /* If an error occurred, clean up by annulling the Mapping pointers and
4521    deleting the new object. */
4522          if ( !astOK ) {
4523             new->map1 = astAnnul( new->map1 );
4524             new->map2 = astAnnul( new->map2 );
4525             new = astDelete( new );
4526          }
4527       }
4528    }
4529 
4530 /* Return a pointer to the new object. */
4531    return new;
4532 }
4533 
astLoadCmpMap_(void * mem,size_t size,AstCmpMapVtab * vtab,const char * name,AstChannel * channel,int * status)4534 AstCmpMap *astLoadCmpMap_( void *mem, size_t size,
4535                            AstCmpMapVtab *vtab, const char *name,
4536                            AstChannel *channel, int *status ) {
4537 /*
4538 *+
4539 *  Name:
4540 *     astLoadCmpMap
4541 
4542 *  Purpose:
4543 *     Load a CmpMap.
4544 
4545 *  Type:
4546 *     Protected function.
4547 
4548 *  Synopsis:
4549 *     #include "cmpmap.h"
4550 *     AstCmpMap *astLoadCmpMap( void *mem, size_t size,
4551 *                               AstCmpMapVtab *vtab, const char *name,
4552 *                               AstChannel *channel )
4553 
4554 *  Class Membership:
4555 *     CmpMap loader.
4556 
4557 *  Description:
4558 *     This function is provided to load a new CmpMap using data read
4559 *     from a Channel. It first loads the data used by the parent class
4560 *     (which allocates memory if necessary) and then initialises a
4561 *     CmpMap structure in this memory, using data read from the input
4562 *     Channel.
4563 *
4564 *     If the "init" flag is set, it also initialises the contents of a
4565 *     virtual function table for a CmpMap at the start of the memory
4566 *     passed via the "vtab" parameter.
4567 
4568 
4569 *  Parameters:
4570 *     mem
4571 *        A pointer to the memory into which the CmpMap is to be
4572 *        loaded.  This must be of sufficient size to accommodate the
4573 *        CmpMap data (sizeof(CmpMap)) plus any data used by derived
4574 *        classes. If a value of NULL is given, this function will
4575 *        allocate the memory itself using the "size" parameter to
4576 *        determine its size.
4577 *     size
4578 *        The amount of memory used by the CmpMap (plus derived class
4579 *        data).  This will be used to allocate memory if a value of
4580 *        NULL is given for the "mem" parameter. This value is also
4581 *        stored in the CmpMap structure, so a valid value must be
4582 *        supplied even if not required for allocating memory.
4583 *
4584 *        If the "vtab" parameter is NULL, the "size" value is ignored
4585 *        and sizeof(AstCmpMap) is used instead.
4586 *     vtab
4587 *        Pointer to the start of the virtual function table to be
4588 *        associated with the new CmpMap. If this is NULL, a pointer to
4589 *        the (static) virtual function table for the CmpMap class is
4590 *        used instead.
4591 *     name
4592 *        Pointer to a constant null-terminated character string which
4593 *        contains the name of the class to which the new object
4594 *        belongs (it is this pointer value that will subsequently be
4595 *        returned by the astGetClass method).
4596 *
4597 *        If the "vtab" parameter is NULL, the "name" value is ignored
4598 *        and a pointer to the string "CmpMap" is used instead.
4599 
4600 *  Returned Value:
4601 *     A pointer to the new CmpMap.
4602 
4603 *  Notes:
4604 *     - A null pointer will be returned if this function is invoked
4605 *     with the global error status set, or if it should fail for any
4606 *     reason.
4607 *-
4608 */
4609 
4610 /* Local Variables: */
4611    astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
4612    AstCmpMap *new;               /* Pointer to the new CmpMap */
4613 
4614 /* Initialise. */
4615    new = NULL;
4616 
4617 /* Check the global error status. */
4618    if ( !astOK ) return new;
4619 
4620 /* Get a pointer to the thread specific global data structure. */
4621    astGET_GLOBALS(channel);
4622 
4623 /* If a NULL virtual function table has been supplied, then this is
4624    the first loader to be invoked for this CmpMap. In this case the
4625    CmpMap belongs to this class, so supply appropriate values to be
4626    passed to the parent class loader (and its parent, etc.). */
4627    if ( !vtab ) {
4628       size = sizeof( AstCmpMap );
4629       vtab = &class_vtab;
4630       name = "CmpMap";
4631 
4632 /* If required, initialise the virtual function table for this class. */
4633       if ( !class_init ) {
4634          astInitCmpMapVtab( vtab, name );
4635          class_init = 1;
4636       }
4637    }
4638 
4639 /* Invoke the parent class loader to load data for all the ancestral
4640    classes of the current one, returning a pointer to the resulting
4641    partly-built CmpMap. */
4642    new = astLoadMapping( mem, size, (AstMappingVtab *) vtab, name,
4643                          channel );
4644 
4645    if ( astOK ) {
4646 
4647 /* Read input data. */
4648 /* ================ */
4649 /* Request the input Channel to read all the input data appropriate to
4650    this class into the internal "values list". */
4651       astReadClassData( channel, "CmpMap" );
4652 
4653 /* Now read each individual data item from this list and use it to
4654    initialise the appropriate instance variable(s) for this class. */
4655 
4656 /* In the case of attributes, we first read the "raw" input value,
4657    supplying the "unset" value as the default. If a "set" value is
4658    obtained, we then use the appropriate (private) Set... member
4659    function to validate and set the value properly. */
4660 
4661 /* Series. */
4662 /* ------- */
4663       new->series = astReadInt( channel, "series", 1 );
4664       new->series = ( new->series != 0 );
4665 
4666 /* First Invert flag. */
4667 /* ------------------ */
4668       new->invert1 = astReadInt( channel, "inva", 0 );
4669       new->invert1 = ( new->invert1 != 0 );
4670 
4671 /* Second Invert flag. */
4672 /* ------------------- */
4673       new->invert2 = astReadInt( channel, "invb", 0 );
4674       new->invert2 = ( new->invert2 != 0 );
4675 
4676 /* First Mapping. */
4677 /* -------------- */
4678       new->map1 = astReadObject( channel, "mapa", NULL );
4679 
4680 /* Second Mapping. */
4681 /* --------------- */
4682       new->map2 = astReadObject( channel, "mapb", NULL );
4683 
4684 /* If an error occurred, clean up by deleting the new CmpMap. */
4685       if ( !astOK ) new = astDelete( new );
4686    }
4687 
4688 /* Return the new CmpMap pointer. */
4689    return new;
4690 }
4691 
4692 /* Virtual function interfaces. */
4693 /* ============================ */
4694 /* These provide the external interface to the virtual functions defined by
4695    this class. Each simply checks the global error status and then locates and
4696    executes the appropriate member function, using the function pointer stored
4697    in the object's virtual function table (this pointer is located using the
4698    astMEMBER macro defined in "object.h").
4699 
4700    Note that the member function may not be the one defined here, as it may
4701    have been over-ridden by a derived class. However, it should still have the
4702    same interface. */
4703 
4704 /* None. */
4705 
4706 
4707 
4708 
4709 
4710 
4711 
4712 
4713