1 /* cke01.f -- translated by f2c (version 19980913).
2    You must link the resulting object file with the libraries:
3 	-lf2c -lm   (in that order)
4 */
5 
6 #include "f2c.h"
7 
8 /* $Procedure      CKE01 ( CK evaluate pointing record, data type 1 ) */
cke01_(logical * needav,doublereal * record,doublereal * cmat,doublereal * av,doublereal * clkout)9 /* Subroutine */ int cke01_(logical *needav, doublereal *record, doublereal *
10 	cmat, doublereal *av, doublereal *clkout)
11 {
12     extern /* Subroutine */ int chkin_(char *, ftnlen), chkout_(char *,
13 	    ftnlen);
14     extern logical return_(void);
15     extern /* Subroutine */ int q2m_(doublereal *, doublereal *);
16 
17 /* $ Abstract */
18 
19 /*     Evaluate a pointing record returned by CKR01 from a CK data type 1 */
20 /*     segment. Return the C-matrix and optionally the angular velocity */
21 /*     vector associated with the time CLKOUT. */
22 
23 /* $ Disclaimer */
24 
25 /*     THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
26 /*     CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
27 /*     GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
28 /*     ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
29 /*     PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
30 /*     TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
31 /*     WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
32 /*     PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
33 /*     SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
34 /*     SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */
35 
36 /*     IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
37 /*     BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
38 /*     LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
39 /*     INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
40 /*     REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
41 /*     REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */
42 
43 /*     RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
44 /*     THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
45 /*     CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
46 /*     ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */
47 
48 /* $ Required_Reading */
49 
50 /*     CK */
51 /*     DAF */
52 /*     ROTATION */
53 
54 /* $ Keywords */
55 
56 /*     POINTING */
57 
58 /* $ Declarations */
59 /* $ Brief_I/O */
60 
61 /*     Variable  I/O  Description */
62 /*     --------  ---  -------------------------------------------------- */
63 /*     NEEDAV     I   True if angular velocity vector is required. */
64 /*     RECORD     I   Data type 1 pointing record. */
65 /*     CMAT       O   C-matrix. */
66 /*     AV         O   Angular velocity vector. */
67 /*     CLKOUT     O   Output spacecraft clock time. */
68 
69 /* $ Detailed_Input */
70 
71 /*     NEEDAV     is true when angular velocity data is requested. */
72 
73 /*     RECORD     is a set of double precision numbers returned by CKR01 */
74 /*                that contain sufficient information from a data type */
75 /*                1 pointing segment to evaluate the C-matrix and */
76 /*                possibly the angular velocity vector (if NEEDAV is */
77 /*                true) for a particular instance. */
78 
79 /*                The contents of RECORD are as follows: */
80 
81 /*                   RECORD( 1 ) = CLKOUT */
82 
83 /*                   RECORD( 2 ) = q0 */
84 /*                   RECORD( 3 ) = q1 */
85 /*                   RECORD( 4 ) = q2 */
86 /*                   RECORD( 5 ) = q3 */
87 
88 /*                   RECORD( 6 ) = Av1  ] */
89 /*                   RECORD( 7 ) = Av2  |-- Optional */
90 /*                   RECORD( 8 ) = Av3  ] */
91 
92 
93 /*                The quantities q0 - q3 represent a quaternion. */
94 /*                The quantities Av1, Av2, and Av3 represent the angular */
95 /*                velocity vector. */
96 
97 /*                CLKOUT is the encoded spacecraft clock time */
98 /*                associated with the quaternion and, optionally, the */
99 /*                angular velocity vector. */
100 
101 /* $ Detailed_Output */
102 
103 /*     CMAT       is a rotation matrix that transforms the components of */
104 /*                of a vector expressed in the reference frame given in */
105 /*                the segment to components expressed in the instrument */
106 /*                fixed frame at time CLKOUT. */
107 
108 /*                Thus, if a vector v has components x, y, z in the */
109 /*                reference frame, then v has components x', y', z' in */
110 /*                the instrument fixed frame at time CLKOUT: */
111 
112 /*                     [ x' ]     [          ] [ x ] */
113 /*                     | y' |  =  |   CMAT   | | y | */
114 /*                     [ z' ]     [          ] [ z ] */
115 
116 /*                If the x', y', z' components are known, use the */
117 /*                transpose of the C-matrix to determine x, y, z as */
118 /*                follows. */
119 
120 /*                     [ x ]      [          ]T    [ x' ] */
121 /*                     | y |  =   |   CMAT   |     | y' | */
122 /*                     [ z ]      [          ]     [ z' ] */
123 /*                              (Transpose of CMAT) */
124 
125 /*     AV         is the angular velocity vector. This is returned only */
126 /*                if it has been requested, as indicated by NEEDAV. In */
127 /*                other words, if NEEDAV is true, the angular velocity */
128 /*                portion of RECORD must be present. */
129 
130 /*                The angular velocity vector is the vector whose */
131 /*                direction gives the right-handed axis about which */
132 /*                the reference frame tied to the instrument is */
133 /*                instantaneously rotating at time CLKOUT. */
134 
135 /*                The angular velocity vector is returned in component */
136 /*                form */
137 
138 /*                         AV = [ AV1  , AV2  , AV3  ] */
139 
140 /*                which is in terms of the reference coordinate frame */
141 /*                specified in the segment descriptor. */
142 
143 /*                The magnitude of AV is the magnitude of the instantane- */
144 /*                ous velocity of the rotation, in radians per second. */
145 
146 /*     CLKOUT     The encoded spacecraft clock time associated with the */
147 /*                returned C-matrix and, optionally, the returned angular */
148 /*                velocity vector. */
149 
150 
151 /* $ Parameters */
152 
153 /*     None. */
154 
155 /* $ Exceptions */
156 
157 /*     1) No checking is done to determine whether RECORD is a valid */
158 /*        record. */
159 
160 /*     2) If NEEDAV is true, then RECORD is assumed to contain angular */
161 /*        velocity data. No checking is performed to verify this */
162 /*        assumption. */
163 
164 /* $ Files */
165 
166 /*     None. */
167 
168 /* $ Particulars */
169 
170 /*     For a detailed description of the structure of a type 1 pointing */
171 /*     segment, see the CK Required Reading file. */
172 
173 /*     The only real work done by CKE01 is to convert the pointing */
174 /*     portion of the record from quaternion form to C-matrix form. */
175 
176 /*     The angular velocity vector will only be returned if it has been */
177 /*     requested. In other words, if NEEDAV is true, the routine will */
178 /*     expect the angular velocity component of the record to be present. */
179 
180 /* $ Examples */
181 
182 /*     A call to a CKEnn routine is almost always preceded by a call to */
183 /*     the corresponding CKRnn routine, which gets the logical record */
184 /*     that CKEnn evaluates. */
185 
186 /*     The following code fragment searches through a file represented */
187 /*     by HANDLE for all segments applicable to the Voyager 2 wide angle */
188 /*     camera, for a particular spacecraft clock time, which have data */
189 /*     type 1.  It then evaluates the pointing for that epoch and prints */
190 /*     the result. */
191 
192 /*     C */
193 /*     C     - Get the spacecraft clock time. Must encode it for use */
194 /*     C       in the C-kernel. */
195 /*     C */
196 /*     C     - Set the time tolerance high to catch anything close to */
197 /*     C       the input time. */
198 /*     C */
199 /*     C     - We don't need angular velocity data. */
200 /*     C */
201 
202 /*           SC     = -32 */
203 /*           INST   = -32002 */
204 /*           TOL    =  1000.D0 */
205 /*           NEEDAV = .FALSE. */
206 /*           DTYPE  =  1 */
207 /*     C */
208 /*     C     Load the Voyager 2 spacecraft clock kernel and the C-kernel. */
209 /*     C */
210 /*           CALL FURNSH ( 'VGR_SCLK.TSC'        ) */
211 /*           CALL DAFOPR ( 'VGR2_CK.BC',  HANDLE ) */
212 /*     C */
213 /*     C     Convert the input request time to ticks. */
214 /*     C */
215 /*           WRITE (*,*) 'Enter spacecraft clock time string:' */
216 /*           READ (*,FMT='(A)') SCLKCH */
217 /*           CALL SCENCD ( SC, SCLKCH, SCLKDP ) */
218 
219 /*     C */
220 /*     C     Search from the beginning through all segments. */
221 /*     C */
222 /*           CALL DAFBFS ( HANDLE ) */
223 /*           CALL DAFFNA ( SFND   ) */
224 
225 /*           DO WHILE ( SFND ) */
226 
227 /*              CALL DAFGN ( IDENT                 ) */
228 /*              CALL DAFGS ( DESCR                 ) */
229 /*              CALL DAFUS ( DESCR, 2, 6, DCD, ICD ) */
230 
231 /*              IF (        INST          .EQ. ICD( 1 ) */
232 /*          .               DTYPE         .EQ. ICD( 3 ) */
233 /*          .        .AND.  SCLKDP + TOL  .GE. DCD( 1 ) */
234 /*          .        .AND.  SCLKDP - TOL  .LE. DCD( 2 )  ) THEN */
235 
236 /*                 CALL CKR01 ( HANDLE, DESCR, SCLKDP, TOL, NEEDAV, */
237 /*          .                   RECORD, FOUND ) */
238 
239 /*                 IF ( FOUND ) THEN */
240 
241 /*                    CALL CKE01 ( NEEDAV, RECORD, CMAT, AV, CLKOUT ) */
242 
243 /*                    WRITE (*,*) 'Segment descriptor and identifier:' */
244 /*                    WRITE (*,*) DCD, ICD */
245 /*                    WRITE (*,*) IDENT */
246 
247 /*                    WRITE (*,*) 'C-matrix:' */
248 /*                    WRITE (*,*) CMAT */
249 
250 /*                 END IF */
251 
252 /*              END IF */
253 
254 /*              CALL DAFFNA ( SFND ) */
255 
256 /*           END DO */
257 
258 /* $ Restrictions */
259 
260 /*     None. */
261 
262 /* $ Literature_References */
263 
264 /*     1) None. */
265 
266 /* $ Author_and_Institution */
267 
268 /*     J.E. McLean    (JPL) */
269 /*     M.J. Spencer   (JPL) */
270 /*     R.E. Thurman   (JPL) */
271 /*     I.M. Underwood (JPL) */
272 
273 /* $ Version */
274 
275 /* -    SPICELIB Version 1.2.1, 22-AUG-2006 (EDW) */
276 
277 /*        Replaced header references to LDPOOL with references */
278 /*        to FURNSH. */
279 
280 /* -    SPICELIB Version 1.2.0, 14-NOV-1995 (WLT) */
281 
282 /*        Changed "inertial frame" to simply reference frame to */
283 /*        reflect new capabilities of the SPICE system. */
284 
285 /* -    SPICELIB Version 1.1.1, 10-MAR-1992 (WLT) */
286 
287 /*        Comment section for permuted index source lines was added */
288 /*        following the header. */
289 
290 /* -    SPICELIB Version 1.1.0, 30-AUG-1991 (MJS) (JML) */
291 
292 /*        1) Previously, in the standard SPICE error handling, the */
293 /*           logical function RETURN was not written as a function; */
294 /*           it is now written as a function. */
295 
296 /*        2) The example program was changed so that the tolerance */
297 /*           and data type are used in selecting which segments to read. */
298 
299 /*        3) It was specified that the angular velocity vector */
300 /*           gives the right-handed axis about which the instrument */
301 /*           frame rotates. */
302 
303 /* -    SPICELIB Version 1.0.1, 02-NOV-1990 (JML) */
304 
305 /*        The example program was corrected so that the input */
306 /*        instrument code was tested against ICD(1) instead of */
307 /*        ICD(3). */
308 
309 /* -    SPICELIB Version 1.0.0, 07-SEP-1990 (RET) (IMU) */
310 
311 /* -& */
312 /* $ Index_Entries */
313 
314 /*     evaluate ck type_1 pointing data record */
315 
316 /* -& */
317 /* $ Revisions */
318 
319 /* -    SPICELIB Version 1.2.0, 14-NOV-1995 (WLT) */
320 
321 /*        Changed "inertial frame" to simply reference frame to */
322 /*        reflect new capabilities of the SPICE system. */
323 
324 /*        This change affects only documentation not code. */
325 
326 /* -    SPICELIB Version 1.1.0, 30-AUG-1991 (MJS) (JML) */
327 
328 /*        1) In the standard SPICE error handling, the line: */
329 
330 /*              IF ( RETURN ) THEN */
331 
332 /*           was changed to */
333 
334 /*              IF ( RETURN() ) THEN */
335 
336 /*        2) The example program was changed so that the tolerance */
337 /*           and data type are used in selecting  which segments to read. */
338 
339 /*        3) It was specified that the angular velocity vector */
340 /*           gives the right-handed axis about which the instrument */
341 /*           frame rotates. */
342 
343 /* -    SPICELIB Version 1.0.1, 02-NOV-1990 (JML) */
344 
345 /*        1) The example program was corrected so that the input */
346 /*           instrument code was tested against ICD(1) instead of */
347 /*           ICD(3). */
348 /*        2) SCLK was removed from the Required Reading section. */
349 
350 /* -    Beta Version 1.1.0, 29-AUG-1990 (MJS) (JEM) */
351 
352 /*        The following changes were made as a result of the */
353 /*        NAIF CK Code and Documentation Review: */
354 
355 /*        1) The argument SCLK was removed from the calling sequence. */
356 /*        2) Header was updated. */
357 /*        3) The call to the routine QUAT2M_3 was replaced by a call to */
358 /*           the routine Q2M. */
359 
360 /* -    Beta Version 1.0.0, 18-MAY-1990 (RET) (IMU) */
361 
362 /* -& */
363 
364 /*     SPICELIB functions */
365 
366 
367 /*     Standard SPICE error handling. */
368 
369     if (return_()) {
370 	return 0;
371     } else {
372 	chkin_("CKE01", (ftnlen)5);
373     }
374 
375 /*     Dissect the record. */
376 
377     *clkout = record[0];
378     q2m_(&record[1], cmat);
379     if (*needav) {
380 	av[0] = record[5];
381 	av[1] = record[6];
382 	av[2] = record[7];
383     }
384     chkout_("CKE01", (ftnlen)5);
385     return 0;
386 } /* cke01_ */
387 
388