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root/radiance/ray/src/util/dctimestep.c
Revision: 2.23
Committed: Fri Nov 2 00:26:55 2012 UTC (10 years, 1 month ago) by greg
Content type: text/plain
Branch: MAIN
Changes since 2.22: +3 -3 lines
Log Message:
Fixed bug using wrong side of BTDF (thanks to David G-M)

File Contents

# User Rev Content
1 greg 2.1 #ifndef lint
2 greg 2.23 static const char RCSid[] = "$Id: dctimestep.c,v 2.22 2012/10/23 22:24:09 greg Exp $";
3 greg 2.1 #endif
4     /*
5     * Compute time-step result using Daylight Coefficient method.
6     *
7     * G. Ward
8     */
9    
10     #include <ctype.h>
11     #include "standard.h"
12     #include "platform.h"
13 greg 2.15 #include "paths.h"
14 greg 2.1 #include "color.h"
15     #include "resolu.h"
16     #include "bsdf.h"
17 greg 2.15 #include "bsdf_m.h"
18 greg 2.1
19     char *progname; /* global argv[0] */
20    
21 greg 2.2 /* Data types for file loading */
22 greg 2.1 enum {DTfromHeader, DTascii, DTfloat, DTdouble, DTrgbe, DTxyze};
23    
24     /* A color coefficient matrix -- vectors have ncols==1 */
25     typedef struct {
26     int nrows, ncols;
27     COLORV cmem[3]; /* extends struct */
28     } CMATRIX;
29    
30     #define COLSPEC (sizeof(COLORV)==sizeof(float) ? "%f %f %f" : "%lf %lf %lf")
31    
32     #define cm_lval(cm,r,c) ((cm)->cmem + 3*((r)*(cm)->ncols + (c)))
33    
34     #define cv_lval(cm,i) ((cm)->cmem + 3*(i))
35    
36     /* Allocate a color coefficient matrix */
37     static CMATRIX *
38     cm_alloc(int nrows, int ncols)
39     {
40     CMATRIX *cm;
41    
42     if ((nrows <= 0) | (ncols <= 0))
43 greg 2.10 error(USER, "attempt to create empty matrix");
44 greg 2.1 cm = (CMATRIX *)malloc(sizeof(CMATRIX) +
45     3*sizeof(COLORV)*(nrows*ncols - 1));
46     if (cm == NULL)
47     error(SYSTEM, "out of memory in cm_alloc()");
48     cm->nrows = nrows;
49     cm->ncols = ncols;
50     return(cm);
51     }
52    
53     #define cm_free(cm) free(cm)
54    
55     /* Resize color coefficient matrix */
56     static CMATRIX *
57     cm_resize(CMATRIX *cm, int nrows)
58     {
59     if (nrows == cm->nrows)
60     return(cm);
61     if (nrows <= 0) {
62     cm_free(cm);
63     return(NULL);
64     }
65     cm = (CMATRIX *)realloc(cm, sizeof(CMATRIX) +
66     3*sizeof(COLORV)*(nrows*cm->ncols - 1));
67     if (cm == NULL)
68     error(SYSTEM, "out of memory in cm_resize()");
69     cm->nrows = nrows;
70     return(cm);
71     }
72    
73     /* Load header to obtain data type */
74     static int
75     getDT(char *s, void *p)
76     {
77     char fmt[32];
78    
79     if (formatval(fmt, s)) {
80     if (!strcmp(fmt, "ascii"))
81     *((int *)p) = DTascii;
82     else if (!strcmp(fmt, "float"))
83     *((int *)p) = DTfloat;
84     else if (!strcmp(fmt, "double"))
85     *((int *)p) = DTdouble;
86     else if (!strcmp(fmt, COLRFMT))
87     *((int *)p) = DTrgbe;
88     else if (!strcmp(fmt, CIEFMT))
89     *((int *)p) = DTxyze;
90     }
91     return(0);
92     }
93    
94     static int
95     getDTfromHeader(FILE *fp)
96     {
97     int dt = DTfromHeader;
98    
99     if (getheader(fp, getDT, &dt) < 0)
100     error(SYSTEM, "header read error");
101     if (dt == DTfromHeader)
102     error(USER, "missing data format in header");
103     return(dt);
104     }
105    
106     /* Allocate and load a matrix from the given file (or stdin if NULL) */
107     static CMATRIX *
108     cm_load(const char *fname, int nrows, int ncols, int dtype)
109     {
110     CMATRIX *cm;
111     FILE *fp = stdin;
112    
113 greg 2.12 if (ncols <= 0)
114     error(USER, "Non-positive number of columns");
115 greg 2.1 if (fname == NULL)
116     fname = "<stdin>";
117     else if ((fp = fopen(fname, "r")) == NULL) {
118     sprintf(errmsg, "cannot open file '%s'", fname);
119     error(SYSTEM, errmsg);
120     }
121     if (dtype != DTascii)
122     SET_FILE_BINARY(fp);
123     if (dtype == DTfromHeader)
124     dtype = getDTfromHeader(fp);
125     switch (dtype) {
126     case DTascii:
127     case DTfloat:
128     case DTdouble:
129     break;
130     default:
131     error(USER, "unexpected data type in cm_load()");
132     }
133     if (nrows <= 0) { /* don't know length? */
134     int guessrows = 147; /* usually big enough */
135     if ((dtype != DTascii) & (fp != stdin)) {
136     long startpos = ftell(fp);
137     if (fseek(fp, 0L, SEEK_END) == 0) {
138     long endpos = ftell(fp);
139     long elemsiz = 3*(dtype==DTfloat ?
140     sizeof(float) : sizeof(double));
141 greg 2.2
142     if ((endpos - startpos) % (ncols*elemsiz)) {
143     sprintf(errmsg,
144     "improper length for binary file '%s'",
145     fname);
146     error(USER, errmsg);
147     }
148     guessrows = (endpos - startpos)/(ncols*elemsiz);
149 greg 2.1 if (fseek(fp, startpos, SEEK_SET) < 0) {
150     sprintf(errmsg,
151     "fseek() error on file '%s'",
152     fname);
153     error(SYSTEM, errmsg);
154     }
155 greg 2.2 nrows = guessrows; /* we're confident */
156 greg 2.1 }
157     }
158     cm = cm_alloc(guessrows, ncols);
159     } else
160     cm = cm_alloc(nrows, ncols);
161     if (cm == NULL)
162     return(NULL);
163     if (dtype == DTascii) { /* read text file */
164     int maxrow = (nrows > 0 ? nrows : 32000);
165     int r, c;
166     for (r = 0; r < maxrow; r++) {
167 greg 2.6 if (r >= cm->nrows) /* need more space? */
168 greg 2.1 cm = cm_resize(cm, 2*cm->nrows);
169     for (c = 0; c < ncols; c++) {
170     COLORV *cv = cm_lval(cm,r,c);
171     if (fscanf(fp, COLSPEC, cv, cv+1, cv+2) != 3)
172 greg 2.6 if ((nrows <= 0) & (r > 0) & !c) {
173 greg 2.1 cm = cm_resize(cm, maxrow=r);
174     break;
175     } else
176     goto EOFerror;
177     }
178     }
179     while ((c = getc(fp)) != EOF)
180     if (!isspace(c)) {
181     sprintf(errmsg,
182     "unexpected data at end of ascii file %s",
183     fname);
184     error(WARNING, errmsg);
185     break;
186     }
187     } else { /* read binary file */
188     if (sizeof(COLORV) == (dtype==DTfloat ? sizeof(float) :
189     sizeof(double))) {
190     int nread = 0;
191     do { /* read all we can */
192     nread += fread(cm->cmem + 3*nread,
193     3*sizeof(COLORV),
194     cm->nrows*cm->ncols - nread,
195     fp);
196     if (nrows <= 0) { /* unknown length */
197     if (nread == cm->nrows*cm->ncols)
198     /* need more space? */
199     cm = cm_resize(cm, 2*cm->nrows);
200 greg 2.6 else if (nread && !(nread % cm->ncols))
201 greg 2.1 /* seem to be done */
202     cm = cm_resize(cm, nread/cm->ncols);
203     else /* ended mid-row */
204     goto EOFerror;
205     } else if (nread < cm->nrows*cm->ncols)
206     goto EOFerror;
207     } while (nread < cm->nrows*cm->ncols);
208    
209     } else if (dtype == DTdouble) {
210     double dc[3]; /* load from double */
211     COLORV *cvp = cm->cmem;
212     int n = nrows*ncols;
213    
214     if (n <= 0)
215     goto not_handled;
216     while (n--) {
217     if (fread(dc, sizeof(double), 3, fp) != 3)
218     goto EOFerror;
219     copycolor(cvp, dc);
220     cvp += 3;
221     }
222     } else /* dtype == DTfloat */ {
223     float fc[3]; /* load from float */
224     COLORV *cvp = cm->cmem;
225     int n = nrows*ncols;
226    
227     if (n <= 0)
228     goto not_handled;
229     while (n--) {
230     if (fread(fc, sizeof(float), 3, fp) != 3)
231     goto EOFerror;
232     copycolor(cvp, fc);
233     cvp += 3;
234     }
235     }
236     if (getc(fp) != EOF) {
237     sprintf(errmsg,
238     "unexpected data at end of binary file %s",
239     fname);
240     error(WARNING, errmsg);
241     }
242     }
243     if (fp != stdin)
244     fclose(fp);
245     return(cm);
246     EOFerror:
247     sprintf(errmsg, "unexpected EOF reading %s",
248     fname);
249     error(USER, errmsg);
250     not_handled:
251     error(INTERNAL, "unhandled data size or length in cm_load()");
252     return(NULL); /* gratis return */
253     }
254    
255 greg 2.20 /* Scale a matrix by a single value */
256     static CMATRIX *
257     cm_scale(const CMATRIX *cm1, const COLOR sca)
258     {
259     CMATRIX *cmr;
260     int dr, dc;
261    
262     cmr = cm_alloc(cm1->nrows, cm1->ncols);
263     if (cmr == NULL)
264     return(NULL);
265     for (dr = 0; dr < cmr->nrows; dr++)
266     for (dc = 0; dc < cmr->ncols; dc++) {
267     const COLORV *sp = cm_lval(cm1,dr,dc);
268     COLORV *dp = cm_lval(cmr,dr,dc);
269     dp[0] = sp[0] * sca[0];
270     dp[1] = sp[1] * sca[1];
271     dp[2] = sp[2] * sca[2];
272     }
273     return(cmr);
274     }
275    
276     /* Multiply two matrices (or a matrix and a vector) and allocate the result */
277 greg 2.1 static CMATRIX *
278     cm_multiply(const CMATRIX *cm1, const CMATRIX *cm2)
279     {
280     CMATRIX *cmr;
281     int dr, dc, i;
282    
283     if ((cm1->ncols <= 0) | (cm1->ncols != cm2->nrows))
284     error(INTERNAL, "matrix dimension mismatch in cm_multiply()");
285     cmr = cm_alloc(cm1->nrows, cm2->ncols);
286     if (cmr == NULL)
287     return(NULL);
288     for (dr = 0; dr < cmr->nrows; dr++)
289     for (dc = 0; dc < cmr->ncols; dc++) {
290     COLORV *dp = cm_lval(cmr,dr,dc);
291     dp[0] = dp[1] = dp[2] = 0;
292     for (i = 0; i < cm1->ncols; i++) {
293     const COLORV *cp1 = cm_lval(cm1,dr,i);
294     const COLORV *cp2 = cm_lval(cm2,i,dc);
295     dp[0] += cp1[0] * cp2[0];
296     dp[1] += cp1[1] * cp2[1];
297     dp[2] += cp1[2] * cp2[2];
298     }
299     }
300     return(cmr);
301     }
302    
303     /* print out matrix as ASCII text -- no header */
304     static void
305     cm_print(const CMATRIX *cm, FILE *fp)
306     {
307     int r, c;
308     const COLORV *mp = cm->cmem;
309    
310     for (r = 0; r < cm->nrows; r++) {
311     for (c = 0; c < cm->ncols; c++, mp += 3)
312     fprintf(fp, "\t%.6e %.6e %.6e", mp[0], mp[1], mp[2]);
313     fputc('\n', fp);
314     }
315     }
316    
317 greg 2.15 /* Convert a BSDF to our matrix representation */
318 greg 2.1 static CMATRIX *
319 greg 2.15 cm_bsdf(const COLOR bsdfLamb, const COLOR specCol, const SDMat *bsdf)
320 greg 2.1 {
321 greg 2.16 CMATRIX *cm = cm_alloc(bsdf->nout, bsdf->ninc);
322 greg 2.3 int nbadohm = 0;
323     int nneg = 0;
324 greg 2.1 int r, c;
325 greg 2.22 /* loop over incident angles */
326 greg 2.16 for (c = 0; c < cm->ncols; c++) {
327 greg 2.17 const double dom = mBSDF_incohm(bsdf,c);
328     /* projected solid angle */
329 greg 2.16 nbadohm += (dom <= 0);
330    
331     for (r = 0; r < cm->nrows; r++) {
332     float f = mBSDF_value(bsdf,c,r);
333     COLORV *mp = cm_lval(cm,r,c);
334     /* check BSDF value */
335     if ((f <= 0) | (dom <= 0)) {
336     nneg += (f < -FTINY);
337     f = .0f;
338 greg 2.3 }
339 greg 2.16 copycolor(mp, specCol);
340     scalecolor(mp, f);
341     addcolor(mp, bsdfLamb);
342     scalecolor(mp, dom);
343 greg 2.3 }
344 greg 2.7 }
345 greg 2.15 if (nneg | nbadohm) {
346 greg 2.3 sprintf(errmsg,
347 greg 2.4 "BTDF has %d negatives and %d bad incoming solid angles",
348     nneg, nbadohm);
349 greg 2.3 error(WARNING, errmsg);
350     }
351 greg 2.1 return(cm);
352     }
353    
354 greg 2.22 /* Convert between input and output indices for reciprocity */
355     static int
356     recip_out_from_in(const SDMat *bsdf, int in_recip)
357     {
358     FVECT v;
359    
360     if (!mBSDF_incvec(v, bsdf, in_recip+.5))
361     return(in_recip); /* XXX should be error! */
362     v[2] = -v[2];
363     return(mBSDF_outndx(bsdf, v));
364     }
365    
366     /* Convert between output and input indices for reciprocity */
367     static int
368     recip_in_from_out(const SDMat *bsdf, int out_recip)
369     {
370     FVECT v;
371    
372     if (!mBSDF_outvec(v, bsdf, out_recip+.5))
373     return(out_recip); /* XXX should be error! */
374     v[2] = -v[2];
375     return(mBSDF_incndx(bsdf, v));
376     }
377    
378     /* Convert a BSDF to our matrix representation, applying reciprocity */
379     static CMATRIX *
380     cm_bsdf_recip(const COLOR bsdfLamb, const COLOR specCol, const SDMat *bsdf)
381     {
382     CMATRIX *cm = cm_alloc(bsdf->ninc, bsdf->nout);
383     int nbadohm = 0;
384     int nneg = 0;
385     int r, c;
386     /* loop over incident angles */
387     for (c = 0; c < cm->ncols; c++) {
388     const int ro = recip_out_from_in(bsdf,c);
389     const double dom = mBSDF_outohm(bsdf,ro);
390     /* projected solid angle */
391     nbadohm += (dom <= 0);
392    
393     for (r = 0; r < cm->nrows; r++) {
394     const int ri = recip_in_from_out(bsdf,r);
395     float f = mBSDF_value(bsdf,ri,ro);
396     COLORV *mp = cm_lval(cm,r,c);
397     /* check BSDF value */
398     if ((f <= 0) | (dom <= 0)) {
399     nneg += (f < -FTINY);
400     f = .0f;
401     }
402     copycolor(mp, specCol);
403     scalecolor(mp, f);
404     addcolor(mp, bsdfLamb);
405     scalecolor(mp, dom);
406     }
407     }
408     if (nneg | nbadohm) {
409     sprintf(errmsg,
410     "BTDF has %d negatives and %d bad incoming solid angles",
411     nneg, nbadohm);
412     error(WARNING, errmsg);
413     }
414     return(cm);
415     }
416    
417 greg 2.15 /* Load and convert a matrix BSDF from the given XML file */
418     static CMATRIX *
419 greg 2.20 cm_loadBSDF(char *fname, COLOR cLamb)
420 greg 2.15 {
421 greg 2.21 CMATRIX *Tmat;
422     char *fpath;
423 greg 2.22 int recip;
424 greg 2.21 SDError ec;
425     SDData myBSDF;
426     SDSpectralDF *tdf;
427     COLOR bsdfLamb, specCol;
428 greg 2.15 /* find path to BSDF file */
429     fpath = getpath(fname, getrlibpath(), R_OK);
430     if (fpath == NULL) {
431     sprintf(errmsg, "cannot find BSDF file '%s'", fname);
432     error(USER, errmsg);
433     }
434 greg 2.16 SDclearBSDF(&myBSDF, fname); /* load XML and check type */
435 greg 2.15 ec = SDloadFile(&myBSDF, fpath);
436     if (ec)
437     error(USER, transSDError(ec));
438 greg 2.20 ccy2rgb(&myBSDF.tLamb.spec, myBSDF.tLamb.cieY/PI, bsdfLamb);
439 greg 2.23 recip = (myBSDF.tb == NULL);
440     tdf = recip ? myBSDF.tf : myBSDF.tb;
441 greg 2.21 if (tdf == NULL) { /* no non-Lambertian transmission? */
442 greg 2.20 if (cLamb != NULL)
443     copycolor(cLamb, bsdfLamb);
444     SDfreeBSDF(&myBSDF);
445     return(NULL);
446     }
447 greg 2.21 if (tdf->ncomp != 1 || tdf->comp[0].func != &SDhandleMtx) {
448 greg 2.15 sprintf(errmsg, "unsupported BSDF '%s'", fpath);
449     error(USER, errmsg);
450     }
451     /* convert BTDF to matrix */
452 greg 2.21 ccy2rgb(&tdf->comp[0].cspec[0], 1., specCol);
453 greg 2.22 Tmat = recip ? cm_bsdf_recip(bsdfLamb, specCol, (SDMat *)tdf->comp[0].dist)
454     : cm_bsdf(bsdfLamb, specCol, (SDMat *)tdf->comp[0].dist);
455 greg 2.20 if (cLamb != NULL) /* Lambertian is included */
456     setcolor(cLamb, .0, .0, .0);
457 greg 2.15 /* free BSDF and return */
458     SDfreeBSDF(&myBSDF);
459     return(Tmat);
460     }
461    
462 greg 2.1 /* Sum together a set of images and write result to stdout */
463     static int
464 greg 2.13 sum_images(const char *fspec, const CMATRIX *cv, FILE *fout)
465 greg 2.1 {
466     int myDT = DTfromHeader;
467     CMATRIX *pmat;
468     COLOR *scanline;
469     int myXR, myYR;
470     int i, y;
471    
472     if (cv->ncols != 1)
473     error(INTERNAL, "expected vector in sum_images()");
474     for (i = 0; i < cv->nrows; i++) {
475     const COLORV *scv = cv_lval(cv,i);
476     char fname[1024];
477     FILE *fp;
478     int dt, xr, yr;
479     COLORV *psp;
480 greg 2.14 /* check for zero */
481 greg 2.19 if ((scv[RED] == 0) & (scv[GRN] == 0) & (scv[BLU] == 0) &&
482     (myDT != DTfromHeader) | (i < cv->nrows-1))
483 greg 2.14 continue;
484 greg 2.1 /* open next picture */
485     sprintf(fname, fspec, i);
486     if ((fp = fopen(fname, "r")) == NULL) {
487     sprintf(errmsg, "cannot open picture '%s'", fname);
488     error(SYSTEM, errmsg);
489     }
490     SET_FILE_BINARY(fp);
491     dt = getDTfromHeader(fp);
492     if ((dt != DTrgbe) & (dt != DTxyze) ||
493     !fscnresolu(&xr, &yr, fp)) {
494     sprintf(errmsg, "file '%s' not a picture", fname);
495     error(USER, errmsg);
496     }
497     if (myDT == DTfromHeader) { /* on first one */
498     myDT = dt;
499     myXR = xr; myYR = yr;
500     scanline = (COLOR *)malloc(sizeof(COLOR)*myXR);
501     if (scanline == NULL)
502     error(SYSTEM, "out of memory in sum_images()");
503     pmat = cm_alloc(myYR, myXR);
504     memset(pmat->cmem, 0, sizeof(COLOR)*myXR*myYR);
505 greg 2.2 /* finish header */
506 greg 2.13 fputformat(myDT==DTrgbe ? COLRFMT : CIEFMT, fout);
507     fputc('\n', fout);
508     fprtresolu(myXR, myYR, fout);
509     fflush(fout);
510 greg 2.1 } else if ((dt != myDT) | (xr != myXR) | (yr != myYR)) {
511     sprintf(errmsg, "picture '%s' format/size mismatch",
512     fname);
513     error(USER, errmsg);
514     }
515     psp = pmat->cmem;
516     for (y = 0; y < yr; y++) { /* read it in */
517     int x;
518     if (freadscan(scanline, xr, fp) < 0) {
519     sprintf(errmsg, "error reading picture '%s'",
520     fname);
521     error(SYSTEM, errmsg);
522     }
523     /* sum in scanline */
524     for (x = 0; x < xr; x++, psp += 3) {
525     multcolor(scanline[x], scv);
526     addcolor(psp, scanline[x]);
527     }
528     }
529     fclose(fp); /* done this picture */
530     }
531     free(scanline);
532     /* write scanlines */
533     for (y = 0; y < myYR; y++)
534 greg 2.13 if (fwritescan((COLOR *)cm_lval(pmat, y, 0), myXR, fout) < 0)
535 greg 2.1 return(0);
536     cm_free(pmat); /* all done */
537 greg 2.13 return(fflush(fout) == 0);
538 greg 2.1 }
539    
540 greg 2.11 /* check to see if a string contains a %d or %o specification */
541     static int
542     hasNumberFormat(const char *s)
543 greg 2.1 {
544 greg 2.18 while (*s) {
545     while (*s != '%')
546     if (!*s++)
547     return(0);
548     if (*++s == '%') { /* ignore "%%" */
549     ++s;
550     continue;
551     }
552     while (isdigit(*s)) /* field length */
553     ++s;
554     /* field we'll use? */
555     if ((*s == 'd') | (*s == 'i') | (*s == 'o') |
556     (*s == 'x') | (*s == 'X'))
557     return(1);
558     }
559     return(0); /* didn't find one */
560 greg 2.1 }
561    
562     int
563     main(int argc, char *argv[])
564     {
565 greg 2.20 CMATRIX *cvec; /* component vector result */
566 greg 2.1
567     progname = argv[0];
568    
569 greg 2.12 if ((argc < 2) | (argc > 5)) {
570     fprintf(stderr, "Usage: %s DCspec [tregvec]\n", progname);
571     fprintf(stderr, " or: %s Vspec Tbsdf.xml Dmat.dat [tregvec]\n",
572     progname);
573 greg 2.1 return(1);
574     }
575 greg 2.12
576 greg 2.13 if (argc > 3) { /* VTDs expression */
577 greg 2.12 CMATRIX *svec, *Dmat, *Tmat, *ivec;
578 greg 2.20 COLOR tLamb;
579 greg 2.12 /* get sky vector */
580     svec = cm_load(argv[4], 0, 1, DTascii);
581     /* load BSDF */
582 greg 2.20 Tmat = cm_loadBSDF(argv[2], tLamb);
583 greg 2.5 /* load Daylight matrix */
584 greg 2.20 Dmat = cm_load(argv[3], Tmat==NULL ? 0 : Tmat->ncols,
585     svec->nrows, DTfromHeader);
586 greg 2.1 /* multiply vector through */
587 greg 2.12 ivec = cm_multiply(Dmat, svec);
588     cm_free(Dmat); cm_free(svec);
589 greg 2.20 if (Tmat == NULL) { /* diffuse only */
590     cvec = cm_scale(ivec, tLamb);
591     } else { /* else apply BTDF matrix */
592     cvec = cm_multiply(Tmat, ivec);
593     cm_free(Tmat);
594     }
595     cm_free(ivec);
596 greg 2.12 } else { /* else just use sky vector */
597     cvec = cm_load(argv[2], 0, 1, DTascii);
598     }
599    
600 greg 2.11 if (hasNumberFormat(argv[1])) { /* generating image */
601 greg 2.1 SET_FILE_BINARY(stdout);
602     newheader("RADIANCE", stdout);
603     printargs(argc, argv, stdout);
604     fputnow(stdout);
605 greg 2.12 if (!sum_images(argv[1], cvec, stdout))
606 greg 2.1 return(1);
607     } else { /* generating vector */
608     CMATRIX *Vmat = cm_load(argv[1], 0, cvec->nrows, DTfromHeader);
609     CMATRIX *rvec = cm_multiply(Vmat, cvec);
610     cm_free(Vmat);
611     cm_print(rvec, stdout);
612     cm_free(rvec);
613     }
614     cm_free(cvec); /* final clean-up */
615     return(0);
616     }