1 /* reordi.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      REORDI ( Reorder an integer array ) */
reordi_(integer * iorder,integer * ndim,integer * array)9 /* Subroutine */ int reordi_(integer *iorder, integer *ndim, integer *array)
10 {
11     /* System generated locals */
12     integer i__1, i__2;
13 
14     /* Local variables */
15     integer hold, temp, index, start;
16 
17 /* $ Abstract */
18 
19 /*      Re-order the elements of an integer array according to */
20 /*      a given order vector. */
21 
22 /* $ Disclaimer */
23 
24 /*     THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
25 /*     CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
26 /*     GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
27 /*     ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
28 /*     PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
29 /*     TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
30 /*     WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
31 /*     PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
32 /*     SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
33 /*     SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */
34 
35 /*     IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
36 /*     BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
37 /*     LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
38 /*     INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
39 /*     REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
40 /*     REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */
41 
42 /*     RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
43 /*     THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
44 /*     CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
45 /*     ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */
46 
47 /* $ Required_Reading */
48 
49 /*     None. */
50 
51 /* $ Keywords */
52 
53 /*      ARRAY,  SORT */
54 
55 /* $ Declarations */
56 /* $ Brief_I/O */
57 
58 /*      VARIABLE  I/O  DESCRIPTION */
59 /*      --------  ---  -------------------------------------------------- */
60 /*      IORDER     I   Order vector to be used to re-order ARRAY. */
61 /*      NDIM       I   Dimension of ARRAY. */
62 /*      ARRAY     I/O  Array to be re-ordered. */
63 
64 /* $ Detailed_Input */
65 
66 /*      IORDER      is the order vector to be used to re-order the input */
67 /*                  array. The first element of IORDER is the index of */
68 /*                  the first item of the re-ordered array, and so on. */
69 
70 /*                  Note that the order imposed by REORDI is not the */
71 /*                  same order that would be imposed by a sorting */
72 /*                  routine. In general, the order vector will have */
73 /*                  been created (by one of the ORDER routines) for */
74 /*                  a related array, as illustrated in the example below. */
75 
76 /*      NDIM        is the number of elements in the input array. */
77 
78 /*      ARRAY       on input, is an array containing some number of */
79 /*                  elements in unspecified order. */
80 
81 /* $ Detailed_Output */
82 
83 /*      ARRAY       on output, is the same array, with the elements */
84 /*                  in re-ordered as specified by IORDER. */
85 
86 /* $ Parameters */
87 
88 /*     None. */
89 
90 /* $ Particulars */
91 
92 /*      REORDI uses a cyclical algorithm to re-order the elements of */
93 /*      the array in place. After re-ordering, element IORDER(1) of */
94 /*      the input array is the first element of the output array, */
95 /*      element IORDER(2) is the input array is the second element of */
96 /*      the output array, and so on. */
97 
98 /*      The order vector used by REORDI is typically created for */
99 /*      a related array by one of the ORDER routines, as shown in */
100 /*      the example below. */
101 
102 /* $ Examples */
103 
104 /*      In the following example, the ORDER and REORD routines are */
105 /*      used to sort four related arrays (containing the names, */
106 /*      masses, integer ID codes, and visual magnitudes for a group */
107 /*      of satellites). This is representative of the typical use of */
108 /*      these routines. */
109 
110 /*            C */
111 /*            C     Sort the object arrays by name. */
112 /*            C */
113 /*                  CALL ORDERC ( NAMES, N, IORDER ) */
114 
115 /*                  CALL REORDC ( IORDER, N, NAMES ) */
116 /*                  CALL REORDD ( IORDER, N, MASSES ) */
117 /*                  CALL REORDI ( IORDER, N, CODES ) */
118 /*                  CALL REORDR ( IORDER, N, VMAGS ) */
119 
120 /* $ Restrictions */
121 
122 /*      None. */
123 
124 /* $ Exceptions */
125 
126 /*      Error free. */
127 
128 /* $ Files */
129 
130 /*      None. */
131 
132 /* $ Author_and_Institution */
133 
134 /*      W.L. Taber      (JPL) */
135 /*      I.M. Underwood  (JPL) */
136 
137 /* $ Literature_References */
138 
139 /*      None. */
140 
141 /* $ Version */
142 
143 /* -     SPICELIB Version 1.0.1, 10-MAR-1992 (WLT) */
144 
145 /*         Comment section for permuted index source lines was added */
146 /*         following the header. */
147 
148 /* -     SPICELIB Version 1.0.0, 31-JAN-1990 (WLT) (IMU) */
149 
150 /* -& */
151 /* $ Index_Entries */
152 
153 /*     reorder an integer array */
154 
155 /* -& */
156 
157 /*     Local variables */
158 
159 
160 /*     If the array doesn't have at least two elements, don't bother. */
161 
162     if (*ndim < 2) {
163 	return 0;
164     }
165 
166 /*     START is the position in the order vector that begins the */
167 /*     current cycle. When all the switches have been made, START */
168 /*     will point to the end of the order vector. */
169 
170     start = 1;
171     while(start < *ndim) {
172 
173 /*        Begin with the element of input vector specified by */
174 /*        IORDER(START). Move it to the correct position in the */
175 /*        array, after saving the element it replaces to TEMP. */
176 /*        HOLD indicates the position of the array element to */
177 /*        be moved to its new position. After the element has */
178 /*        been moved, HOLD indicates the position of an available */
179 /*        space within the array. */
180 
181 	index = start;
182 	temp = array[index - 1];
183 	hold = iorder[index - 1];
184 
185 /*        As each slot in the output array is filled in, the sign */
186 /*        of the corresponding element in the order vector is changed */
187 /*        from positive to negative. This way, we know which elements */
188 /*        have already been ordered when looking for the beginning of */
189 /*        the next cycle. */
190 
191 /*        Keep going until HOLD points to the first array element */
192 /*        moved during the current cycle. This ends the cycle. */
193 
194 	while(hold != start) {
195 	    array[index - 1] = array[hold - 1];
196 	    index = hold;
197 	    hold = iorder[hold - 1];
198 	    iorder[index - 1] = -iorder[index - 1];
199 	}
200 
201 /*        The last element in the cycle is restored from TEMP. */
202 
203 	array[index - 1] = temp;
204 	iorder[hold - 1] = -iorder[hold - 1];
205 
206 /*        Begin the next cycle at the next element in the order */
207 /*        vector with a positive sign. (That is, the next one */
208 /*        that hasn't been moved.) */
209 
210 	while(iorder[start - 1] < 0 && start < *ndim) {
211 	    ++start;
212 	}
213     }
214 
215 /*     Restore the original signs of the elements of the order vector, */
216 /*     in case the vector is to be used again with another array. */
217 
218     i__1 = *ndim;
219     for (index = 1; index <= i__1; ++index) {
220 	iorder[index - 1] = (i__2 = iorder[index - 1], abs(i__2));
221     }
222     return 0;
223 } /* reordi_ */
224 
225