xref: /petsc/src/mat/impls/aij/seq/aij.c (revision 2f3bf4bf7047bfe2e206ae42678cbec2288fc25e)
1 #ifdef PETSC_RCS_HEADER
2 static char vcid[] = "$Id: aij.c,v 1.318 1999/03/29 16:50:07 bsmith Exp bsmith $";
3 #endif
4 
5 /*
6     Defines the basic matrix operations for the AIJ (compressed row)
7   matrix storage format.
8 */
9 
10 #include "sys.h"
11 #include "src/mat/impls/aij/seq/aij.h"
12 #include "src/vec/vecimpl.h"
13 #include "src/inline/spops.h"
14 #include "src/inline/dot.h"
15 #include "bitarray.h"
16 
17 /*
18     Basic AIJ format ILU based on drop tolerance
19 */
20 #undef __FUNC__
21 #define __FUNC__ "MatILUDTFactor_SeqAIJ"
22 int MatILUDTFactor_SeqAIJ(Mat A,double dt,int maxnz,IS row,IS col,Mat *fact)
23 {
24   /* Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data; */
25 
26   PetscFunctionBegin;
27   SETERRQ(1,0,"Not implemented");
28 #if !defined(USE_PETSC_DEBUG)
29   PetscFunctionReturn(0);
30 #endif
31 }
32 
33 extern int MatToSymmetricIJ_SeqAIJ(int,int*,int*,int,int,int**,int**);
34 
35 #undef __FUNC__
36 #define __FUNC__ "MatGetRowIJ_SeqAIJ"
37 int MatGetRowIJ_SeqAIJ(Mat A,int oshift,PetscTruth symmetric,int *m,int **ia,int **ja,
38                            PetscTruth *done)
39 {
40   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
41   int        ierr,i,ishift;
42 
43   PetscFunctionBegin;
44   *m     = A->m;
45   if (!ia) PetscFunctionReturn(0);
46   ishift = a->indexshift;
47   if (symmetric) {
48     ierr = MatToSymmetricIJ_SeqAIJ(a->m,a->i,a->j,ishift,oshift,ia,ja); CHKERRQ(ierr);
49   } else if (oshift == 0 && ishift == -1) {
50     int nz = a->i[a->m];
51     /* malloc space and  subtract 1 from i and j indices */
52     *ia = (int *) PetscMalloc( (a->m+1)*sizeof(int) ); CHKPTRQ(*ia);
53     *ja = (int *) PetscMalloc( (nz+1)*sizeof(int) ); CHKPTRQ(*ja);
54     for ( i=0; i<nz; i++ ) (*ja)[i] = a->j[i] - 1;
55     for ( i=0; i<a->m+1; i++ ) (*ia)[i] = a->i[i] - 1;
56   } else if (oshift == 1 && ishift == 0) {
57     int nz = a->i[a->m] + 1;
58     /* malloc space and  add 1 to i and j indices */
59     *ia = (int *) PetscMalloc( (a->m+1)*sizeof(int) ); CHKPTRQ(*ia);
60     *ja = (int *) PetscMalloc( (nz+1)*sizeof(int) ); CHKPTRQ(*ja);
61     for ( i=0; i<nz; i++ ) (*ja)[i] = a->j[i] + 1;
62     for ( i=0; i<a->m+1; i++ ) (*ia)[i] = a->i[i] + 1;
63   } else {
64     *ia = a->i; *ja = a->j;
65   }
66 
67   PetscFunctionReturn(0);
68 }
69 
70 #undef __FUNC__
71 #define __FUNC__ "MatRestoreRowIJ_SeqAIJ"
72 int MatRestoreRowIJ_SeqAIJ(Mat A,int oshift,PetscTruth symmetric,int *n,int **ia,int **ja,
73                                PetscTruth *done)
74 {
75   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
76   int        ishift = a->indexshift;
77 
78   PetscFunctionBegin;
79   if (!ia) PetscFunctionReturn(0);
80   if (symmetric || (oshift == 0 && ishift == -1) || (oshift == 1 && ishift == 0)) {
81     PetscFree(*ia);
82     PetscFree(*ja);
83   }
84   PetscFunctionReturn(0);
85 }
86 
87 #undef __FUNC__
88 #define __FUNC__ "MatGetColumnIJ_SeqAIJ"
89 int MatGetColumnIJ_SeqAIJ(Mat A,int oshift,PetscTruth symmetric,int *nn,int **ia,int **ja,
90                            PetscTruth *done)
91 {
92   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
93   int        ierr,i,ishift = a->indexshift,*collengths,*cia,*cja,n = A->n,m = A->m;
94   int        nz = a->i[m]+ishift,row,*jj,mr,col;
95 
96   PetscFunctionBegin;
97   *nn     = A->n;
98   if (!ia) PetscFunctionReturn(0);
99   if (symmetric) {
100     ierr = MatToSymmetricIJ_SeqAIJ(a->m,a->i,a->j,ishift,oshift,ia,ja); CHKERRQ(ierr);
101   } else {
102     collengths = (int *) PetscMalloc( (n+1)*sizeof(int) ); CHKPTRQ(collengths);
103     PetscMemzero(collengths,n*sizeof(int));
104     cia        = (int *) PetscMalloc( (n+1)*sizeof(int) ); CHKPTRQ(cia);
105     cja        = (int *) PetscMalloc( (nz+1)*sizeof(int) ); CHKPTRQ(cja);
106     jj = a->j;
107     for ( i=0; i<nz; i++ ) {
108       collengths[jj[i] + ishift]++;
109     }
110     cia[0] = oshift;
111     for ( i=0; i<n; i++) {
112       cia[i+1] = cia[i] + collengths[i];
113     }
114     PetscMemzero(collengths,n*sizeof(int));
115     jj = a->j;
116     for ( row=0; row<m; row++ ) {
117       mr = a->i[row+1] - a->i[row];
118       for ( i=0; i<mr; i++ ) {
119         col = *jj++ + ishift;
120         cja[cia[col] + collengths[col]++ - oshift] = row + oshift;
121       }
122     }
123     PetscFree(collengths);
124     *ia = cia; *ja = cja;
125   }
126 
127   PetscFunctionReturn(0);
128 }
129 
130 #undef __FUNC__
131 #define __FUNC__ "MatRestoreColumnIJ_SeqAIJ"
132 int MatRestoreColumnIJ_SeqAIJ(Mat A,int oshift,PetscTruth symmetric,int *n,int **ia,
133                                      int **ja,PetscTruth *done)
134 {
135   PetscFunctionBegin;
136   if (!ia) PetscFunctionReturn(0);
137 
138   PetscFree(*ia);
139   PetscFree(*ja);
140 
141   PetscFunctionReturn(0);
142 }
143 
144 #define CHUNKSIZE   15
145 
146 #undef __FUNC__
147 #define __FUNC__ "MatSetValues_SeqAIJ"
148 int MatSetValues_SeqAIJ(Mat A,int m,int *im,int n,int *in,Scalar *v,InsertMode is)
149 {
150   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
151   int        *rp,k,low,high,t,ii,row,nrow,i,col,l,rmax, N, sorted = a->sorted;
152   int        *imax = a->imax, *ai = a->i, *ailen = a->ilen,roworiented = a->roworiented;
153   int        *aj = a->j, nonew = a->nonew,shift = a->indexshift;
154   Scalar     *ap,value, *aa = a->a;
155 
156   PetscFunctionBegin;
157   for ( k=0; k<m; k++ ) { /* loop over added rows */
158     row  = im[k];
159     if (row < 0) continue;
160 #if defined(USE_PETSC_BOPT_g)
161     if (row >= a->m) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,0,"Row too large: row %d max %d",row,a->m);
162 #endif
163     rp   = aj + ai[row] + shift; ap = aa + ai[row] + shift;
164     rmax = imax[row]; nrow = ailen[row];
165     low = 0;
166     for ( l=0; l<n; l++ ) { /* loop over added columns */
167       if (in[l] < 0) continue;
168 #if defined(USE_PETSC_BOPT_g)
169       if (in[l] >= a->n) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,0,"Column too large: col %d max %d",in[l],a->n);
170 #endif
171       col = in[l] - shift;
172       if (roworiented) {
173         value = v[l + k*n];
174       } else {
175         value = v[k + l*m];
176       }
177       if (!sorted) low = 0; high = nrow;
178       while (high-low > 5) {
179         t = (low+high)/2;
180         if (rp[t] > col) high = t;
181         else             low  = t;
182       }
183       for ( i=low; i<high; i++ ) {
184         if (rp[i] > col) break;
185         if (rp[i] == col) {
186           if (is == ADD_VALUES) ap[i] += value;
187           else                  ap[i] = value;
188           goto noinsert;
189         }
190       }
191       if (nonew == 1) goto noinsert;
192       else if (nonew == -1) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Inserting a new nonzero in the matrix");
193       if (nrow >= rmax) {
194         /* there is no extra room in row, therefore enlarge */
195         int    new_nz = ai[a->m] + CHUNKSIZE,len,*new_i,*new_j;
196         Scalar *new_a;
197 
198         if (nonew == -2) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Inserting a new nonzero in the matrix");
199 
200         /* malloc new storage space */
201         len     = new_nz*(sizeof(int)+sizeof(Scalar))+(a->m+1)*sizeof(int);
202         new_a   = (Scalar *) PetscMalloc( len ); CHKPTRQ(new_a);
203         new_j   = (int *) (new_a + new_nz);
204         new_i   = new_j + new_nz;
205 
206         /* copy over old data into new slots */
207         for ( ii=0; ii<row+1; ii++ ) {new_i[ii] = ai[ii];}
208         for ( ii=row+1; ii<a->m+1; ii++ ) {new_i[ii] = ai[ii]+CHUNKSIZE;}
209         PetscMemcpy(new_j,aj,(ai[row]+nrow+shift)*sizeof(int));
210         len = (new_nz - CHUNKSIZE - ai[row] - nrow - shift);
211         PetscMemcpy(new_j+ai[row]+shift+nrow+CHUNKSIZE,aj+ai[row]+shift+nrow,len*sizeof(int));
212         PetscMemcpy(new_a,aa,(ai[row]+nrow+shift)*sizeof(Scalar));
213         PetscMemcpy(new_a+ai[row]+shift+nrow+CHUNKSIZE,aa+ai[row]+shift+nrow,len*sizeof(Scalar));
214         /* free up old matrix storage */
215         PetscFree(a->a);
216         if (!a->singlemalloc) {PetscFree(a->i);PetscFree(a->j);}
217         aa = a->a = new_a; ai = a->i = new_i; aj = a->j = new_j;
218         a->singlemalloc = 1;
219 
220         rp   = aj + ai[row] + shift; ap = aa + ai[row] + shift;
221         rmax = imax[row] = imax[row] + CHUNKSIZE;
222         PLogObjectMemory(A,CHUNKSIZE*(sizeof(int) + sizeof(Scalar)));
223         a->maxnz += CHUNKSIZE;
224         a->reallocs++;
225       }
226       N = nrow++ - 1; a->nz++;
227       /* shift up all the later entries in this row */
228       for ( ii=N; ii>=i; ii-- ) {
229         rp[ii+1] = rp[ii];
230         ap[ii+1] = ap[ii];
231       }
232       rp[i] = col;
233       ap[i] = value;
234       noinsert:;
235       low = i + 1;
236     }
237     ailen[row] = nrow;
238   }
239   PetscFunctionReturn(0);
240 }
241 
242 #undef __FUNC__
243 #define __FUNC__ "MatGetValues_SeqAIJ"
244 int MatGetValues_SeqAIJ(Mat A,int m,int *im,int n,int *in,Scalar *v)
245 {
246   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
247   int        *rp, k, low, high, t, row, nrow, i, col, l, *aj = a->j;
248   int        *ai = a->i, *ailen = a->ilen, shift = a->indexshift;
249   Scalar     *ap, *aa = a->a, zero = 0.0;
250 
251   PetscFunctionBegin;
252   for ( k=0; k<m; k++ ) { /* loop over rows */
253     row  = im[k];
254     if (row < 0) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Negative row");
255     if (row >= a->m) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Row too large");
256     rp   = aj + ai[row] + shift; ap = aa + ai[row] + shift;
257     nrow = ailen[row];
258     for ( l=0; l<n; l++ ) { /* loop over columns */
259       if (in[l] < 0) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Negative column");
260       if (in[l] >= a->n) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Column too large");
261       col = in[l] - shift;
262       high = nrow; low = 0; /* assume unsorted */
263       while (high-low > 5) {
264         t = (low+high)/2;
265         if (rp[t] > col) high = t;
266         else             low  = t;
267       }
268       for ( i=low; i<high; i++ ) {
269         if (rp[i] > col) break;
270         if (rp[i] == col) {
271           *v++ = ap[i];
272           goto finished;
273         }
274       }
275       *v++ = zero;
276       finished:;
277     }
278   }
279   PetscFunctionReturn(0);
280 }
281 
282 
283 #undef __FUNC__
284 #define __FUNC__ "MatView_SeqAIJ_Binary"
285 int MatView_SeqAIJ_Binary(Mat A,Viewer viewer)
286 {
287   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
288   int        i, fd, *col_lens, ierr;
289 
290   PetscFunctionBegin;
291   ierr = ViewerBinaryGetDescriptor(viewer,&fd); CHKERRQ(ierr);
292   col_lens = (int *) PetscMalloc( (4+a->m)*sizeof(int) ); CHKPTRQ(col_lens);
293   col_lens[0] = MAT_COOKIE;
294   col_lens[1] = a->m;
295   col_lens[2] = a->n;
296   col_lens[3] = a->nz;
297 
298   /* store lengths of each row and write (including header) to file */
299   for ( i=0; i<a->m; i++ ) {
300     col_lens[4+i] = a->i[i+1] - a->i[i];
301   }
302   ierr = PetscBinaryWrite(fd,col_lens,4+a->m,PETSC_INT,1); CHKERRQ(ierr);
303   PetscFree(col_lens);
304 
305   /* store column indices (zero start index) */
306   if (a->indexshift) {
307     for ( i=0; i<a->nz; i++ ) a->j[i]--;
308   }
309   ierr = PetscBinaryWrite(fd,a->j,a->nz,PETSC_INT,0); CHKERRQ(ierr);
310   if (a->indexshift) {
311     for ( i=0; i<a->nz; i++ ) a->j[i]++;
312   }
313 
314   /* store nonzero values */
315   ierr = PetscBinaryWrite(fd,a->a,a->nz,PETSC_SCALAR,0); CHKERRQ(ierr);
316   PetscFunctionReturn(0);
317 }
318 
319 #undef __FUNC__
320 #define __FUNC__ "MatView_SeqAIJ_ASCII"
321 int MatView_SeqAIJ_ASCII(Mat A,Viewer viewer)
322 {
323   Mat_SeqAIJ  *a = (Mat_SeqAIJ *) A->data;
324   int         ierr, i,j, m = a->m, shift = a->indexshift, format, flg1,flg2;
325   FILE        *fd;
326   char        *outputname;
327 
328   PetscFunctionBegin;
329   ierr = ViewerASCIIGetPointer(viewer,&fd); CHKERRQ(ierr);
330   ierr = ViewerGetOutputname(viewer,&outputname); CHKERRQ(ierr);
331   ierr = ViewerGetFormat(viewer,&format);
332   if (format == VIEWER_FORMAT_ASCII_INFO) {
333     PetscFunctionReturn(0);
334   } else if (format == VIEWER_FORMAT_ASCII_INFO_LONG) {
335     ierr = OptionsHasName(PETSC_NULL,"-mat_aij_no_inode",&flg1); CHKERRQ(ierr);
336     ierr = OptionsHasName(PETSC_NULL,"-mat_no_unroll",&flg2); CHKERRQ(ierr);
337     if (flg1 || flg2) {ierr = ViewerASCIIPrintf(viewer,"  not using I-node routines\n");CHKERRQ(ierr);}
338     else {ierr = ViewerASCIIPrintf(viewer,"  using I-node routines: found %d nodes, limit used is %d\n",a->inode.node_count,a->inode.limit);CHKERRQ(ierr);}
339   } else if (format == VIEWER_FORMAT_ASCII_MATLAB) {
340     int nofinalvalue = 0;
341     if ((a->i[m] == a->i[m-1]) || (a->j[a->nz-1] != a->n-!shift)) {
342       nofinalvalue = 1;
343     }
344     fprintf(fd,"%% Size = %d %d \n",m,a->n);
345     fprintf(fd,"%% Nonzeros = %d \n",a->nz);
346     fprintf(fd,"zzz = zeros(%d,3);\n",a->nz+nofinalvalue);
347     fprintf(fd,"zzz = [\n");
348 
349     for (i=0; i<m; i++) {
350       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
351 #if defined(USE_PETSC_COMPLEX)
352         fprintf(fd,"%d %d  %18.16e + %18.16e i \n",i+1,a->j[j]+!shift,PetscReal(a->a[j]),PetscImaginary(a->a[j]));
353 #else
354         fprintf(fd,"%d %d  %18.16e\n", i+1, a->j[j]+!shift, a->a[j]);
355 #endif
356       }
357     }
358     if (nofinalvalue) {
359       fprintf(fd,"%d %d  %18.16e\n", m, a->n, 0.0);
360     }
361     if (outputname) fprintf(fd,"];\n %s = spconvert(zzz);\n",outputname);
362     else            fprintf(fd,"];\n M = spconvert(zzz);\n");
363   } else if (format == VIEWER_FORMAT_ASCII_COMMON) {
364     for ( i=0; i<m; i++ ) {
365       fprintf(fd,"row %d:",i);
366       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
367 #if defined(USE_PETSC_COMPLEX)
368         if (PetscImaginary(a->a[j]) > 0.0 && PetscReal(a->a[j]) != 0.0)
369           fprintf(fd," %d %g + %g i",a->j[j]+shift,PetscReal(a->a[j]),PetscImaginary(a->a[j]));
370         else if (PetscImaginary(a->a[j]) < 0.0 && PetscReal(a->a[j]) != 0.0)
371           fprintf(fd," %d %g - %g i",a->j[j]+shift,PetscReal(a->a[j]),-PetscImaginary(a->a[j]));
372         else if (PetscReal(a->a[j]) != 0.0)
373           fprintf(fd," %d %g ",a->j[j]+shift,PetscReal(a->a[j]));
374 #else
375         if (a->a[j] != 0.0) fprintf(fd," %d %g ",a->j[j]+shift,a->a[j]);
376 #endif
377       }
378       fprintf(fd,"\n");
379     }
380   } else if (format == VIEWER_FORMAT_ASCII_SYMMODU) {
381     int nzd=0, fshift=1, *sptr;
382     sptr = (int *) PetscMalloc( (m+1)*sizeof(int) ); CHKPTRQ(sptr);
383     for ( i=0; i<m; i++ ) {
384       sptr[i] = nzd+1;
385       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
386         if (a->j[j] >= i) {
387 #if defined(USE_PETSC_COMPLEX)
388           if (PetscImaginary(a->a[j]) != 0.0 || PetscReal(a->a[j]) != 0.0) nzd++;
389 #else
390           if (a->a[j] != 0.0) nzd++;
391 #endif
392         }
393       }
394     }
395     sptr[m] = nzd+1;
396     fprintf(fd," %d %d\n\n",m,nzd);
397     for ( i=0; i<m+1; i+=6 ) {
398       if (i+4<m) fprintf(fd," %d %d %d %d %d %d\n",sptr[i],sptr[i+1],sptr[i+2],sptr[i+3],sptr[i+4],sptr[i+5]);
399       else if (i+3<m) fprintf(fd," %d %d %d %d %d\n",sptr[i],sptr[i+1],sptr[i+2],sptr[i+3],sptr[i+4]);
400       else if (i+2<m) fprintf(fd," %d %d %d %d\n",sptr[i],sptr[i+1],sptr[i+2],sptr[i+3]);
401       else if (i+1<m) fprintf(fd," %d %d %d\n",sptr[i],sptr[i+1],sptr[i+2]);
402       else if (i<m)   fprintf(fd," %d %d\n",sptr[i],sptr[i+1]);
403       else            fprintf(fd," %d\n",sptr[i]);
404     }
405     fprintf(fd,"\n");
406     PetscFree(sptr);
407     for ( i=0; i<m; i++ ) {
408       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
409         if (a->j[j] >= i) fprintf(fd," %d ",a->j[j]+fshift);
410       }
411       fprintf(fd,"\n");
412     }
413     fprintf(fd,"\n");
414     for ( i=0; i<m; i++ ) {
415       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
416         if (a->j[j] >= i) {
417 #if defined(USE_PETSC_COMPLEX)
418           if (PetscImaginary(a->a[j]) != 0.0 || PetscReal(a->a[j]) != 0.0)
419             fprintf(fd," %18.16e %18.16e ",PetscReal(a->a[j]),PetscImaginary(a->a[j]));
420 #else
421           if (a->a[j] != 0.0) fprintf(fd," %18.16e ",a->a[j]);
422 #endif
423         }
424       }
425       fprintf(fd,"\n");
426     }
427   } else if (format == VIEWER_FORMAT_ASCII_DENSE) {
428     int    cnt = 0,jcnt;
429     Scalar value;
430 
431     for ( i=0; i<m; i++ ) {
432       jcnt = 0;
433       for ( j=0; j<a->n; j++ ) {
434         if ( jcnt < a->i[i+1]-a->i[i] && j == a->j[cnt]) {
435           value = a->a[cnt++];
436           jcnt++;
437         } else {
438           value = 0.0;
439         }
440 #if defined(USE_PETSC_COMPLEX)
441         fprintf(fd," %7.5e+%7.5e i ",PetscReal(value),PetscImaginary(value));
442 #else
443         fprintf(fd," %7.5e ",value);
444 #endif
445       }
446         fprintf(fd,"\n");
447     }
448   } else {
449     for ( i=0; i<m; i++ ) {
450       fprintf(fd,"row %d:",i);
451       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
452 #if defined(USE_PETSC_COMPLEX)
453         if (PetscImaginary(a->a[j]) > 0.0) {
454           fprintf(fd," %d %g + %g i",a->j[j]+shift,PetscReal(a->a[j]),PetscImaginary(a->a[j]));
455         } else if (PetscImaginary(a->a[j]) < 0.0) {
456           fprintf(fd," %d %g - %g i",a->j[j]+shift,PetscReal(a->a[j]),-PetscImaginary(a->a[j]));
457         } else {
458           fprintf(fd," %d %g ",a->j[j]+shift,PetscReal(a->a[j]));
459         }
460 #else
461         fprintf(fd," %d %g ",a->j[j]+shift,a->a[j]);
462 #endif
463       }
464       fprintf(fd,"\n");
465     }
466   }
467   fflush(fd);
468   PetscFunctionReturn(0);
469 }
470 
471 #undef __FUNC__
472 #define __FUNC__ "MatView_SeqAIJ_Draw_Zoom"
473 int MatView_SeqAIJ_Draw_Zoom(Draw draw,void *Aa)
474 {
475   Mat         A = (Mat) Aa;
476   Mat_SeqAIJ  *a = (Mat_SeqAIJ *) A->data;
477   int         ierr, i,j, m = a->m, shift = a->indexshift,color,rank;
478   int         format;
479   double      xl,yl,xr,yr,x_l,x_r,y_l,y_r,maxv = 0.0;
480   Viewer      viewer;
481   MPI_Comm    comm;
482 
483   PetscFunctionBegin;
484   /*
485       This is nasty. If this is called from an originally parallel matrix
486    then all processes call this, but only the first has the matrix so the
487    rest should return immediately.
488   */
489   ierr = PetscObjectGetComm((PetscObject)draw,&comm);CHKERRQ(ierr);
490   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
491   if (rank) PetscFunctionReturn(0);
492 
493   ierr = PetscObjectQuery((PetscObject)A,"Zoomviewer",(PetscObject*) &viewer);CHKERRQ(ierr);
494   ierr = ViewerGetFormat(viewer,&format); CHKERRQ(ierr);
495 
496   ierr = DrawGetCoordinates(draw,&xl,&yl,&xr,&yr); CHKERRQ(ierr);
497   /* loop over matrix elements drawing boxes */
498 
499   if (format != VIEWER_FORMAT_DRAW_CONTOUR) {
500     /* Blue for negative, Cyan for zero and  Red for positive */
501     color = DRAW_BLUE;
502     for ( i=0; i<m; i++ ) {
503       y_l = m - i - 1.0; y_r = y_l + 1.0;
504       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
505         x_l = a->j[j] + shift; x_r = x_l + 1.0;
506 #if defined(USE_PETSC_COMPLEX)
507         if (PetscReal(a->a[j]) >=  0.) continue;
508 #else
509         if (a->a[j] >=  0.) continue;
510 #endif
511         ierr = DrawRectangle(draw,x_l,y_l,x_r,y_r,color,color,color,color);CHKERRQ(ierr);
512       }
513     }
514     color = DRAW_CYAN;
515     for ( i=0; i<m; i++ ) {
516       y_l = m - i - 1.0; y_r = y_l + 1.0;
517       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
518         x_l = a->j[j] + shift; x_r = x_l + 1.0;
519         if (a->a[j] !=  0.) continue;
520         ierr = DrawRectangle(draw,x_l,y_l,x_r,y_r,color,color,color,color);CHKERRQ(ierr);
521       }
522     }
523     color = DRAW_RED;
524     for ( i=0; i<m; i++ ) {
525       y_l = m - i - 1.0; y_r = y_l + 1.0;
526       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
527         x_l = a->j[j] + shift; x_r = x_l + 1.0;
528 #if defined(USE_PETSC_COMPLEX)
529         if (PetscReal(a->a[j]) <=  0.) continue;
530 #else
531         if (a->a[j] <=  0.) continue;
532 #endif
533         ierr = DrawRectangle(draw,x_l,y_l,x_r,y_r,color,color,color,color);CHKERRQ(ierr);
534       }
535     }
536   } else {
537     /* use contour shading to indicate magnitude of values */
538     /* first determine max of all nonzero values */
539     int    nz = a->nz,count;
540     Draw   popup;
541     double scale;
542 
543     for ( i=0; i<nz; i++ ) {
544       if (PetscAbsScalar(a->a[i]) > maxv) maxv = PetscAbsScalar(a->a[i]);
545     }
546     scale = (245.0 - DRAW_BASIC_COLORS)/maxv;
547     ierr  = DrawGetPopup(draw,&popup); CHKERRQ(ierr);
548     ierr  = DrawScalePopup(popup,0.0,maxv); CHKERRQ(ierr);
549     count = 0;
550     for ( i=0; i<m; i++ ) {
551       y_l = m - i - 1.0; y_r = y_l + 1.0;
552       for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
553         x_l = a->j[j] + shift; x_r = x_l + 1.0;
554         color = DRAW_BASIC_COLORS + (int)(scale*PetscAbsScalar(a->a[count]));
555         ierr  = DrawRectangle(draw,x_l,y_l,x_r,y_r,color,color,color,color);CHKERRQ(ierr);
556         count++;
557       }
558     }
559   }
560   PetscFunctionReturn(0);
561 }
562 
563 #undef __FUNC__
564 #define __FUNC__ "MatView_SeqAIJ_Draw"
565 int MatView_SeqAIJ_Draw(Mat A,Viewer viewer)
566 {
567   Mat_SeqAIJ *a = (Mat_SeqAIJ*) A->data;
568   int        ierr;
569   Draw       draw;
570   double     xr,yr,xl,yl,h,w;
571   PetscTruth isnull;
572 
573   PetscFunctionBegin;
574   ierr = ViewerDrawGetDraw(viewer,0,&draw); CHKERRQ(ierr);
575   ierr = DrawIsNull(draw,&isnull); CHKERRQ(ierr);
576   if (isnull) PetscFunctionReturn(0);
577 
578   ierr = PetscObjectCompose((PetscObject)A,"Zoomviewer",(PetscObject)viewer);CHKERRQ(ierr);
579   xr  = a->n; yr = a->m; h = yr/10.0; w = xr/10.0;
580   xr += w;    yr += h;  xl = -w;     yl = -h;
581   ierr = DrawSetCoordinates(draw,xl,yl,xr,yr); CHKERRQ(ierr);
582   ierr = DrawZoom(draw,MatView_SeqAIJ_Draw_Zoom,A); CHKERRQ(ierr);
583   ierr = PetscObjectCompose((PetscObject)A,"Zoomviewer",PETSC_NULL);CHKERRQ(ierr);
584   PetscFunctionReturn(0);
585 }
586 
587 #undef __FUNC__
588 #define __FUNC__ "MatView_SeqAIJ"
589 int MatView_SeqAIJ(Mat A,Viewer viewer)
590 {
591   Mat_SeqAIJ  *a = (Mat_SeqAIJ*) A->data;
592   ViewerType  vtype;
593   int         ierr;
594 
595   PetscFunctionBegin;
596   ierr = ViewerGetType(viewer,&vtype); CHKERRQ(ierr);
597   if (PetscTypeCompare(vtype,SOCKET_VIEWER)) {
598     ierr = ViewerSocketPutSparse_Private(viewer,a->m,a->n,a->nz,a->a,a->i,a->j);CHKERRQ(ierr);
599   } else if (PetscTypeCompare(vtype,ASCII_VIEWER)){
600     ierr = MatView_SeqAIJ_ASCII(A,viewer); CHKERRQ(ierr);
601   } else if (PetscTypeCompare(vtype,BINARY_VIEWER)) {
602     ierr = MatView_SeqAIJ_Binary(A,viewer); CHKERRQ(ierr);
603   } else if (PetscTypeCompare(vtype,DRAW_VIEWER)) {
604     ierr = MatView_SeqAIJ_Draw(A,viewer); CHKERRQ(ierr);
605   } else {
606     SETERRQ(1,1,"Viewer type not supported by PETSc object");
607   }
608   PetscFunctionReturn(0);
609 }
610 
611 extern int Mat_AIJ_CheckInode(Mat);
612 #undef __FUNC__
613 #define __FUNC__ "MatAssemblyEnd_SeqAIJ"
614 int MatAssemblyEnd_SeqAIJ(Mat A,MatAssemblyType mode)
615 {
616   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
617   int        fshift = 0,i,j,*ai = a->i, *aj = a->j, *imax = a->imax,ierr;
618   int        m = a->m, *ip, N, *ailen = a->ilen,shift = a->indexshift,rmax = 0;
619   Scalar     *aa = a->a, *ap;
620 
621   PetscFunctionBegin;
622   if (mode == MAT_FLUSH_ASSEMBLY) PetscFunctionReturn(0);
623 
624   if (m) rmax = ailen[0]; /* determine row with most nonzeros */
625   for ( i=1; i<m; i++ ) {
626     /* move each row back by the amount of empty slots (fshift) before it*/
627     fshift += imax[i-1] - ailen[i-1];
628     rmax   = PetscMax(rmax,ailen[i]);
629     if (fshift) {
630       ip = aj + ai[i] + shift; ap = aa + ai[i] + shift;
631       N = ailen[i];
632       for ( j=0; j<N; j++ ) {
633         ip[j-fshift] = ip[j];
634         ap[j-fshift] = ap[j];
635       }
636     }
637     ai[i] = ai[i-1] + ailen[i-1];
638   }
639   if (m) {
640     fshift += imax[m-1] - ailen[m-1];
641     ai[m] = ai[m-1] + ailen[m-1];
642   }
643   /* reset ilen and imax for each row */
644   for ( i=0; i<m; i++ ) {
645     ailen[i] = imax[i] = ai[i+1] - ai[i];
646   }
647   a->nz = ai[m] + shift;
648 
649   /* diagonals may have moved, so kill the diagonal pointers */
650   if (fshift && a->diag) {
651     PetscFree(a->diag);
652     PLogObjectMemory(A,-(m+1)*sizeof(int));
653     a->diag = 0;
654   }
655   PLogInfo(A,"MatAssemblyEnd_SeqAIJ:Matrix size: %d X %d; storage space: %d unneeded, %d used\n",
656            m,a->n,fshift,a->nz);
657   PLogInfo(A,"MatAssemblyEnd_SeqAIJ:Number of mallocs during MatSetValues() is %d\n",
658            a->reallocs);
659   PLogInfo(A,"MatAssemblyEnd_SeqAIJ:Most nonzeros in any row is %d\n",rmax);
660   a->reallocs          = 0;
661   A->info.nz_unneeded  = (double)fshift;
662 
663   /* check out for identical nodes. If found, use inode functions */
664   ierr = Mat_AIJ_CheckInode(A); CHKERRQ(ierr);
665   PetscFunctionReturn(0);
666 }
667 
668 #undef __FUNC__
669 #define __FUNC__ "MatZeroEntries_SeqAIJ"
670 int MatZeroEntries_SeqAIJ(Mat A)
671 {
672   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
673 
674   PetscFunctionBegin;
675   PetscMemzero(a->a,(a->i[a->m]+a->indexshift)*sizeof(Scalar));
676   PetscFunctionReturn(0);
677 }
678 
679 #undef __FUNC__
680 #define __FUNC__ "MatDestroy_SeqAIJ"
681 int MatDestroy_SeqAIJ(Mat A)
682 {
683   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
684   int        ierr;
685 
686   PetscFunctionBegin;
687   if (--A->refct > 0) PetscFunctionReturn(0);
688 
689   if (A->mapping) {
690     ierr = ISLocalToGlobalMappingDestroy(A->mapping); CHKERRQ(ierr);
691   }
692   if (A->bmapping) {
693     ierr = ISLocalToGlobalMappingDestroy(A->bmapping); CHKERRQ(ierr);
694   }
695   if (A->rmap) {
696     ierr = MapDestroy(A->rmap);CHKERRQ(ierr);
697   }
698   if (A->cmap) {
699     ierr = MapDestroy(A->cmap);CHKERRQ(ierr);
700   }
701   if (a->idiag) PetscFree(a->idiag);
702 #if defined(USE_PETSC_LOG)
703   PLogObjectState((PetscObject)A,"Rows=%d, Cols=%d, NZ=%d",a->m,a->n,a->nz);
704 #endif
705   PetscFree(a->a);
706   if (!a->singlemalloc) { PetscFree(a->i); PetscFree(a->j);}
707   if (a->diag) PetscFree(a->diag);
708   if (a->ilen) PetscFree(a->ilen);
709   if (a->imax) PetscFree(a->imax);
710   if (a->solve_work) PetscFree(a->solve_work);
711   if (a->inode.size) PetscFree(a->inode.size);
712   if (a->icol) {ierr = ISDestroy(a->icol);CHKERRQ(ierr);}
713   if (a->saved_values) PetscFree(a->saved_values);
714   PetscFree(a);
715 
716   PLogObjectDestroy(A);
717   PetscHeaderDestroy(A);
718   PetscFunctionReturn(0);
719 }
720 
721 #undef __FUNC__
722 #define __FUNC__ "MatCompress_SeqAIJ"
723 int MatCompress_SeqAIJ(Mat A)
724 {
725   PetscFunctionBegin;
726   PetscFunctionReturn(0);
727 }
728 
729 #undef __FUNC__
730 #define __FUNC__ "MatSetOption_SeqAIJ"
731 int MatSetOption_SeqAIJ(Mat A,MatOption op)
732 {
733   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
734 
735   PetscFunctionBegin;
736   if      (op == MAT_ROW_ORIENTED)                 a->roworiented = 1;
737   else if (op == MAT_COLUMN_ORIENTED)              a->roworiented = 0;
738   else if (op == MAT_COLUMNS_SORTED)               a->sorted      = 1;
739   else if (op == MAT_COLUMNS_UNSORTED)             a->sorted      = 0;
740   else if (op == MAT_NO_NEW_NONZERO_LOCATIONS)     a->nonew       = 1;
741   else if (op == MAT_NEW_NONZERO_LOCATION_ERR)     a->nonew       = -1;
742   else if (op == MAT_NEW_NONZERO_ALLOCATION_ERR)   a->nonew       = -2;
743   else if (op == MAT_YES_NEW_NONZERO_LOCATIONS)    a->nonew       = 0;
744   else if (op == MAT_ROWS_SORTED ||
745            op == MAT_ROWS_UNSORTED ||
746            op == MAT_SYMMETRIC ||
747            op == MAT_STRUCTURALLY_SYMMETRIC ||
748            op == MAT_YES_NEW_DIAGONALS ||
749            op == MAT_IGNORE_OFF_PROC_ENTRIES||
750            op == MAT_USE_HASH_TABLE)
751     PLogInfo(A,"MatSetOption_SeqAIJ:Option ignored\n");
752   else if (op == MAT_NO_NEW_DIAGONALS) {
753     SETERRQ(PETSC_ERR_SUP,0,"MAT_NO_NEW_DIAGONALS");
754   } else if (op == MAT_INODE_LIMIT_1)            a->inode.limit  = 1;
755   else if (op == MAT_INODE_LIMIT_2)            a->inode.limit  = 2;
756   else if (op == MAT_INODE_LIMIT_3)            a->inode.limit  = 3;
757   else if (op == MAT_INODE_LIMIT_4)            a->inode.limit  = 4;
758   else if (op == MAT_INODE_LIMIT_5)            a->inode.limit  = 5;
759   else SETERRQ(PETSC_ERR_SUP,0,"unknown option");
760   PetscFunctionReturn(0);
761 }
762 
763 #undef __FUNC__
764 #define __FUNC__ "MatGetDiagonal_SeqAIJ"
765 int MatGetDiagonal_SeqAIJ(Mat A,Vec v)
766 {
767   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
768   int        i,j, n,shift = a->indexshift,ierr;
769   Scalar     *x, zero = 0.0;
770 
771   PetscFunctionBegin;
772   ierr = VecSet(&zero,v);CHKERRQ(ierr);
773   ierr = VecGetArray(v,&x);;CHKERRQ(ierr);
774   ierr = VecGetLocalSize(v,&n);;CHKERRQ(ierr);
775   if (n != a->m) SETERRQ(PETSC_ERR_ARG_SIZ,0,"Nonconforming matrix and vector");
776   for ( i=0; i<a->m; i++ ) {
777     for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
778       if (a->j[j]+shift == i) {
779         x[i] = a->a[j];
780         break;
781       }
782     }
783   }
784   ierr = VecRestoreArray(v,&x);;CHKERRQ(ierr);
785   PetscFunctionReturn(0);
786 }
787 
788 /* -------------------------------------------------------*/
789 /* Should check that shapes of vectors and matrices match */
790 /* -------------------------------------------------------*/
791 #undef __FUNC__
792 #define __FUNC__ "MatMultTrans_SeqAIJ"
793 int MatMultTrans_SeqAIJ(Mat A,Vec xx,Vec yy)
794 {
795   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
796   Scalar     *x, *y, *v, alpha;
797   int        ierr,m = a->m, n, i, *idx, shift = a->indexshift;
798 
799   PetscFunctionBegin;
800   ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
801   ierr = VecGetArray(yy,&y);CHKERRQ(ierr);
802   PetscMemzero(y,a->n*sizeof(Scalar));
803   y = y + shift; /* shift for Fortran start by 1 indexing */
804   for ( i=0; i<m; i++ ) {
805     idx   = a->j + a->i[i] + shift;
806     v     = a->a + a->i[i] + shift;
807     n     = a->i[i+1] - a->i[i];
808     alpha = x[i];
809     while (n-->0) {y[*idx++] += alpha * *v++;}
810   }
811   PLogFlops(2*a->nz - a->n);
812   ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
813   ierr = VecRestoreArray(yy,&y);CHKERRQ(ierr);
814   PetscFunctionReturn(0);
815 }
816 
817 #undef __FUNC__
818 #define __FUNC__ "MatMultTransAdd_SeqAIJ"
819 int MatMultTransAdd_SeqAIJ(Mat A,Vec xx,Vec zz,Vec yy)
820 {
821   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
822   Scalar     *x, *y, *v, alpha;
823   int        ierr,m = a->m, n, i, *idx,shift = a->indexshift;
824 
825   PetscFunctionBegin;
826   if (zz != yy) {ierr = VecCopy(zz,yy);CHKERRQ(ierr);}
827   ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
828   ierr = VecGetArray(yy,&y);CHKERRQ(ierr);
829   y = y + shift; /* shift for Fortran start by 1 indexing */
830   for ( i=0; i<m; i++ ) {
831     idx   = a->j + a->i[i] + shift;
832     v     = a->a + a->i[i] + shift;
833     n     = a->i[i+1] - a->i[i];
834     alpha = x[i];
835     while (n-->0) {y[*idx++] += alpha * *v++;}
836   }
837   PLogFlops(2*a->nz);
838   ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
839   ierr = VecRestoreArray(yy,&y);CHKERRQ(ierr);
840   PetscFunctionReturn(0);
841 }
842 
843 #undef __FUNC__
844 #define __FUNC__ "MatMult_SeqAIJ"
845 int MatMult_SeqAIJ(Mat A,Vec xx,Vec yy)
846 {
847   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
848   Scalar     *x, *y, *v, sum;
849   int        ierr,m = a->m, *idx, shift = a->indexshift,*ii;
850 #if !defined(USE_FORTRAN_KERNEL_MULTAIJ)
851   int        n, i, jrow,j;
852 #endif
853 
854 #if defined(HAVE_PRAGMA_DISJOINT)
855 #pragma disjoint(*x,*y,*v)
856 #endif
857 
858   PetscFunctionBegin;
859   ierr = VecGetArray(xx,&x); CHKERRQ(ierr);
860   ierr = VecGetArray(yy,&y); CHKERRQ(ierr);
861   x    = x + shift;    /* shift for Fortran start by 1 indexing */
862   idx  = a->j;
863   v    = a->a;
864   ii   = a->i;
865 #if defined(USE_FORTRAN_KERNEL_MULTAIJ)
866   fortranmultaij_(&m,x,ii,idx+shift,v+shift,y);
867 #else
868   v    += shift; /* shift for Fortran start by 1 indexing */
869   idx  += shift;
870   for ( i=0; i<m; i++ ) {
871     jrow = ii[i];
872     n    = ii[i+1] - jrow;
873     sum  = 0.0;
874     for ( j=0; j<n; j++) {
875       sum += v[jrow]*x[idx[jrow]]; jrow++;
876      }
877     y[i] = sum;
878   }
879 #endif
880   PLogFlops(2*a->nz - m);
881   ierr = VecRestoreArray(xx,&x); CHKERRQ(ierr);
882   ierr = VecRestoreArray(yy,&y); CHKERRQ(ierr);
883   PetscFunctionReturn(0);
884 }
885 
886 #undef __FUNC__
887 #define __FUNC__ "MatMultAdd_SeqAIJ"
888 int MatMultAdd_SeqAIJ(Mat A,Vec xx,Vec yy,Vec zz)
889 {
890   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
891   Scalar     *x, *y, *z, *v, sum;
892   int        ierr,m = a->m, *idx, shift = a->indexshift,*ii;
893 #if !defined(USE_FORTRAN_KERNEL_MULTADDAIJ)
894   int        n,i,jrow,j;
895 #endif
896 
897   PetscFunctionBegin;
898   ierr = VecGetArray(xx,&x); CHKERRQ(ierr);
899   ierr = VecGetArray(yy,&y); CHKERRQ(ierr);
900   if (zz != yy) {
901     ierr = VecGetArray(zz,&z); CHKERRQ(ierr);
902   } else {
903     z = y;
904   }
905   x    = x + shift; /* shift for Fortran start by 1 indexing */
906   idx  = a->j;
907   v    = a->a;
908   ii   = a->i;
909 #if defined(USE_FORTRAN_KERNEL_MULTADDAIJ)
910   fortranmultaddaij_(&m,x,ii,idx+shift,v+shift,y,z);
911 #else
912   v   += shift; /* shift for Fortran start by 1 indexing */
913   idx += shift;
914   for ( i=0; i<m; i++ ) {
915     jrow = ii[i];
916     n    = ii[i+1] - jrow;
917     sum  = y[i];
918     for ( j=0; j<n; j++) {
919       sum += v[jrow]*x[idx[jrow]]; jrow++;
920      }
921     z[i] = sum;
922   }
923 #endif
924   PLogFlops(2*a->nz);
925   ierr = VecRestoreArray(xx,&x); CHKERRQ(ierr);
926   ierr = VecRestoreArray(yy,&y); CHKERRQ(ierr);
927   if (zz != yy) {
928     ierr = VecRestoreArray(zz,&z); CHKERRQ(ierr);
929   }
930   PetscFunctionReturn(0);
931 }
932 
933 /*
934      Adds diagonal pointers to sparse matrix structure.
935 */
936 #undef __FUNC__
937 #define __FUNC__ "MatMarkDiag_SeqAIJ"
938 int MatMarkDiag_SeqAIJ(Mat A)
939 {
940   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
941   int        i,j, *diag, m = a->m,shift = a->indexshift;
942 
943   PetscFunctionBegin;
944   diag = (int *) PetscMalloc( (m+1)*sizeof(int)); CHKPTRQ(diag);
945   PLogObjectMemory(A,(m+1)*sizeof(int));
946   for ( i=0; i<a->m; i++ ) {
947     diag[i] = a->i[i+1];
948     for ( j=a->i[i]+shift; j<a->i[i+1]+shift; j++ ) {
949       if (a->j[j]+shift == i) {
950         diag[i] = j - shift;
951         break;
952       }
953     }
954   }
955   a->diag = diag;
956   PetscFunctionReturn(0);
957 }
958 
959 /*
960      Checks for missing diagonals
961 */
962 #undef __FUNC__
963 #define __FUNC__ "MatMissingDiag_SeqAIJ"
964 int MatMissingDiag_SeqAIJ(Mat A)
965 {
966   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
967   int        *diag = a->diag, *jj = a->j,i,shift = a->indexshift;
968 
969   PetscFunctionBegin;
970   for ( i=0; i<a->m; i++ ) {
971     if (jj[diag[i]+shift] != i-shift) {
972       SETERRQ1(1,1,"Matrix is missing diagonal number %d",i);
973     }
974   }
975   PetscFunctionReturn(0);
976 }
977 
978 #undef __FUNC__
979 #define __FUNC__ "MatRelax_SeqAIJ"
980 int MatRelax_SeqAIJ(Mat A,Vec bb,double omega,MatSORType flag,double fshift,int its,Vec xx)
981 {
982   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
983   Scalar     *x, *b, *bs,  d, *xs, sum, *v = a->a,*t=0,scale,*ts, *xb,*idiag=0;
984   int        ierr, *idx, *diag,n = a->n, m = a->m, i, shift = a->indexshift;
985 
986   PetscFunctionBegin;
987   ierr = VecGetArray(xx,&x); CHKERRQ(ierr);
988   if (xx != bb) {
989     ierr = VecGetArray(bb,&b);CHKERRQ(ierr);
990   } else {
991     b = x;
992   }
993 
994   if (!a->diag) {ierr = MatMarkDiag_SeqAIJ(A);CHKERRQ(ierr);}
995   diag = a->diag;
996   xs   = x + shift; /* shifted by one for index start of a or a->j*/
997   if (flag == SOR_APPLY_UPPER) {
998    /* apply ( U + D/omega) to the vector */
999     bs = b + shift;
1000     for ( i=0; i<m; i++ ) {
1001         d    = fshift + a->a[diag[i] + shift];
1002         n    = a->i[i+1] - diag[i] - 1;
1003 	PLogFlops(2*n-1);
1004         idx  = a->j + diag[i] + (!shift);
1005         v    = a->a + diag[i] + (!shift);
1006         sum  = b[i]*d/omega;
1007         SPARSEDENSEDOT(sum,bs,v,idx,n);
1008         x[i] = sum;
1009     }
1010     ierr = VecRestoreArray(xx,&x); CHKERRQ(ierr);
1011     if (bb != xx) {ierr = VecRestoreArray(bb,&b);CHKERRQ(ierr);}
1012     PetscFunctionReturn(0);
1013   }
1014 
1015   /* setup workspace for Eisenstat */
1016   if (flag & SOR_EISENSTAT) {
1017     if (!a->idiag) {
1018       a->idiag = (Scalar *) PetscMalloc(2*m*sizeof(Scalar));CHKPTRQ(a->idiag);
1019       a->ssor  = a->idiag + m;
1020       v        = a->a;
1021       for ( i=0; i<m; i++ ) { a->idiag[i] = 1.0/v[diag[i]];}
1022     }
1023     t     = a->ssor;
1024     idiag = a->idiag;
1025   }
1026     /* Let  A = L + U + D; where L is lower trianglar,
1027     U is upper triangular, E is diagonal; This routine applies
1028 
1029             (L + E)^{-1} A (U + E)^{-1}
1030 
1031     to a vector efficiently using Eisenstat's trick. This is for
1032     the case of SSOR preconditioner, so E is D/omega where omega
1033     is the relaxation factor.
1034     */
1035 
1036   if (flag == SOR_APPLY_LOWER) {
1037     SETERRQ(PETSC_ERR_SUP,0,"SOR_APPLY_LOWER is not done");
1038   } else if ((flag & SOR_EISENSTAT) && omega == 1.0 && shift == 0 && fshift == 0.0) {
1039     /* special case for omega = 1.0 saves flops and some integer ops */
1040     Scalar *v2;
1041 
1042     v2    = a->a;
1043     /*  x = (E + U)^{-1} b */
1044     for ( i=m-1; i>=0; i-- ) {
1045       n    = a->i[i+1] - diag[i] - 1;
1046       idx  = a->j + diag[i] + 1;
1047       v    = a->a + diag[i] + 1;
1048       sum  = b[i];
1049       SPARSEDENSEMDOT(sum,xs,v,idx,n);
1050       x[i] = sum*idiag[i];
1051 
1052       /*  t = b - (2*E - D)x */
1053       t[i] = b[i] - (v2[diag[i]])*x[i];
1054     }
1055 
1056     /*  t = (E + L)^{-1}t */
1057     diag = a->diag;
1058     for ( i=0; i<m; i++ ) {
1059       n    = diag[i] - a->i[i];
1060       idx  = a->j + a->i[i];
1061       v    = a->a + a->i[i];
1062       sum  = t[i];
1063       SPARSEDENSEMDOT(sum,t,v,idx,n);
1064       t[i]  = sum*idiag[i];
1065 
1066       /*  x = x + t */
1067       x[i] += t[i];
1068     }
1069 
1070     PLogFlops(3*m-1 + 2*a->nz);
1071     ierr = VecRestoreArray(xx,&x); CHKERRQ(ierr);
1072     if (bb != xx) {ierr = VecRestoreArray(bb,&b);CHKERRQ(ierr);}
1073     PetscFunctionReturn(0);
1074   } else if (flag & SOR_EISENSTAT) {
1075     /* Let  A = L + U + D; where L is lower trianglar,
1076     U is upper triangular, E is diagonal; This routine applies
1077 
1078             (L + E)^{-1} A (U + E)^{-1}
1079 
1080     to a vector efficiently using Eisenstat's trick. This is for
1081     the case of SSOR preconditioner, so E is D/omega where omega
1082     is the relaxation factor.
1083     */
1084     scale = (2.0/omega) - 1.0;
1085 
1086     /*  x = (E + U)^{-1} b */
1087     for ( i=m-1; i>=0; i-- ) {
1088       d    = fshift + a->a[diag[i] + shift];
1089       n    = a->i[i+1] - diag[i] - 1;
1090       idx  = a->j + diag[i] + (!shift);
1091       v    = a->a + diag[i] + (!shift);
1092       sum  = b[i];
1093       SPARSEDENSEMDOT(sum,xs,v,idx,n);
1094       x[i] = omega*(sum/d);
1095     }
1096 
1097     /*  t = b - (2*E - D)x */
1098     v = a->a;
1099     for ( i=0; i<m; i++ ) { t[i] = b[i] - scale*(v[*diag++ + shift])*x[i]; }
1100 
1101     /*  t = (E + L)^{-1}t */
1102     ts = t + shift; /* shifted by one for index start of a or a->j*/
1103     diag = a->diag;
1104     for ( i=0; i<m; i++ ) {
1105       d    = fshift + a->a[diag[i]+shift];
1106       n    = diag[i] - a->i[i];
1107       idx  = a->j + a->i[i] + shift;
1108       v    = a->a + a->i[i] + shift;
1109       sum  = t[i];
1110       SPARSEDENSEMDOT(sum,ts,v,idx,n);
1111       t[i] = omega*(sum/d);
1112       /*  x = x + t */
1113       x[i] += t[i];
1114     }
1115 
1116     PLogFlops(6*m-1 + 2*a->nz);
1117     ierr = VecRestoreArray(xx,&x); CHKERRQ(ierr);
1118     if (bb != xx) {ierr = VecRestoreArray(bb,&b);CHKERRQ(ierr);}
1119     PetscFunctionReturn(0);
1120   }
1121   if (flag & SOR_ZERO_INITIAL_GUESS) {
1122     if (flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP){
1123       for ( i=0; i<m; i++ ) {
1124         d    = fshift + a->a[diag[i]+shift];
1125         n    = diag[i] - a->i[i];
1126 	PLogFlops(2*n-1);
1127         idx  = a->j + a->i[i] + shift;
1128         v    = a->a + a->i[i] + shift;
1129         sum  = b[i];
1130         SPARSEDENSEMDOT(sum,xs,v,idx,n);
1131         x[i] = omega*(sum/d);
1132       }
1133       xb = x;
1134     } else xb = b;
1135     if ((flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP) &&
1136         (flag & SOR_BACKWARD_SWEEP || flag & SOR_LOCAL_BACKWARD_SWEEP)) {
1137       for ( i=0; i<m; i++ ) {
1138         x[i] *= a->a[diag[i]+shift];
1139       }
1140       PLogFlops(m);
1141     }
1142     if (flag & SOR_BACKWARD_SWEEP || flag & SOR_LOCAL_BACKWARD_SWEEP){
1143       for ( i=m-1; i>=0; i-- ) {
1144         d    = fshift + a->a[diag[i] + shift];
1145         n    = a->i[i+1] - diag[i] - 1;
1146 	PLogFlops(2*n-1);
1147         idx  = a->j + diag[i] + (!shift);
1148         v    = a->a + diag[i] + (!shift);
1149         sum  = xb[i];
1150         SPARSEDENSEMDOT(sum,xs,v,idx,n);
1151         x[i] = omega*(sum/d);
1152       }
1153     }
1154     its--;
1155   }
1156   while (its--) {
1157     if (flag & SOR_FORWARD_SWEEP || flag & SOR_LOCAL_FORWARD_SWEEP){
1158       for ( i=0; i<m; i++ ) {
1159         d    = fshift + a->a[diag[i]+shift];
1160         n    = a->i[i+1] - a->i[i];
1161 	PLogFlops(2*n-1);
1162         idx  = a->j + a->i[i] + shift;
1163         v    = a->a + a->i[i] + shift;
1164         sum  = b[i];
1165         SPARSEDENSEMDOT(sum,xs,v,idx,n);
1166         x[i] = (1. - omega)*x[i] + omega*(sum + a->a[diag[i]+shift]*x[i])/d;
1167       }
1168     }
1169     if (flag & SOR_BACKWARD_SWEEP || flag & SOR_LOCAL_BACKWARD_SWEEP){
1170       for ( i=m-1; i>=0; i-- ) {
1171         d    = fshift + a->a[diag[i] + shift];
1172         n    = a->i[i+1] - a->i[i];
1173 	PLogFlops(2*n-1);
1174         idx  = a->j + a->i[i] + shift;
1175         v    = a->a + a->i[i] + shift;
1176         sum  = b[i];
1177         SPARSEDENSEMDOT(sum,xs,v,idx,n);
1178         x[i] = (1. - omega)*x[i] + omega*(sum + a->a[diag[i]+shift]*x[i])/d;
1179       }
1180     }
1181   }
1182   ierr = VecRestoreArray(xx,&x); CHKERRQ(ierr);
1183   if (bb != xx) {ierr = VecRestoreArray(bb,&b);CHKERRQ(ierr);}
1184   PetscFunctionReturn(0);
1185 }
1186 
1187 #undef __FUNC__
1188 #define __FUNC__ "MatGetInfo_SeqAIJ"
1189 int MatGetInfo_SeqAIJ(Mat A,MatInfoType flag,MatInfo *info)
1190 {
1191   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1192 
1193   PetscFunctionBegin;
1194   info->rows_global    = (double)a->m;
1195   info->columns_global = (double)a->n;
1196   info->rows_local     = (double)a->m;
1197   info->columns_local  = (double)a->n;
1198   info->block_size     = 1.0;
1199   info->nz_allocated   = (double)a->maxnz;
1200   info->nz_used        = (double)a->nz;
1201   info->nz_unneeded    = (double)(a->maxnz - a->nz);
1202   info->assemblies     = (double)A->num_ass;
1203   info->mallocs        = (double)a->reallocs;
1204   info->memory         = A->mem;
1205   if (A->factor) {
1206     info->fill_ratio_given  = A->info.fill_ratio_given;
1207     info->fill_ratio_needed = A->info.fill_ratio_needed;
1208     info->factor_mallocs    = A->info.factor_mallocs;
1209   } else {
1210     info->fill_ratio_given  = 0;
1211     info->fill_ratio_needed = 0;
1212     info->factor_mallocs    = 0;
1213   }
1214   PetscFunctionReturn(0);
1215 }
1216 
1217 extern int MatLUFactorSymbolic_SeqAIJ(Mat,IS,IS,double,Mat*);
1218 extern int MatLUFactorNumeric_SeqAIJ(Mat,Mat*);
1219 extern int MatLUFactor_SeqAIJ(Mat,IS,IS,double);
1220 extern int MatSolve_SeqAIJ(Mat,Vec,Vec);
1221 extern int MatSolveAdd_SeqAIJ(Mat,Vec,Vec,Vec);
1222 extern int MatSolveTrans_SeqAIJ(Mat,Vec,Vec);
1223 extern int MatSolveTransAdd_SeqAIJ(Mat,Vec,Vec,Vec);
1224 
1225 #undef __FUNC__
1226 #define __FUNC__ "MatZeroRows_SeqAIJ"
1227 int MatZeroRows_SeqAIJ(Mat A,IS is,Scalar *diag)
1228 {
1229   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1230   int         i,ierr,N, *rows,m = a->m - 1,shift = a->indexshift;
1231 
1232   PetscFunctionBegin;
1233   ierr = ISGetSize(is,&N); CHKERRQ(ierr);
1234   ierr = ISGetIndices(is,&rows); CHKERRQ(ierr);
1235   if (diag) {
1236     for ( i=0; i<N; i++ ) {
1237       if (rows[i] < 0 || rows[i] > m) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"row out of range");
1238       if (a->ilen[rows[i]] > 0) {
1239         a->ilen[rows[i]] = 1;
1240         a->a[a->i[rows[i]]+shift] = *diag;
1241         a->j[a->i[rows[i]]+shift] = rows[i]+shift;
1242       } else { /* in case row was completely empty */
1243         ierr = MatSetValues_SeqAIJ(A,1,&rows[i],1,&rows[i],diag,INSERT_VALUES);CHKERRQ(ierr);
1244       }
1245     }
1246   } else {
1247     for ( i=0; i<N; i++ ) {
1248       if (rows[i] < 0 || rows[i] > m) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"row out of range");
1249       a->ilen[rows[i]] = 0;
1250     }
1251   }
1252   ierr = ISRestoreIndices(is,&rows);CHKERRQ(ierr);
1253   ierr = MatAssemblyEnd_SeqAIJ(A,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
1254   PetscFunctionReturn(0);
1255 }
1256 
1257 #undef __FUNC__
1258 #define __FUNC__ "MatGetSize_SeqAIJ"
1259 int MatGetSize_SeqAIJ(Mat A,int *m,int *n)
1260 {
1261   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1262 
1263   PetscFunctionBegin;
1264   if (m) *m = a->m;
1265   if (n) *n = a->n;
1266   PetscFunctionReturn(0);
1267 }
1268 
1269 #undef __FUNC__
1270 #define __FUNC__ "MatGetOwnershipRange_SeqAIJ"
1271 int MatGetOwnershipRange_SeqAIJ(Mat A,int *m,int *n)
1272 {
1273   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1274 
1275   PetscFunctionBegin;
1276   *m = 0; *n = a->m;
1277   PetscFunctionReturn(0);
1278 }
1279 
1280 #undef __FUNC__
1281 #define __FUNC__ "MatGetRow_SeqAIJ"
1282 int MatGetRow_SeqAIJ(Mat A,int row,int *nz,int **idx,Scalar **v)
1283 {
1284   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1285   int        *itmp,i,shift = a->indexshift;
1286 
1287   PetscFunctionBegin;
1288   if (row < 0 || row >= a->m) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Row out of range");
1289 
1290   *nz = a->i[row+1] - a->i[row];
1291   if (v) *v = a->a + a->i[row] + shift;
1292   if (idx) {
1293     itmp = a->j + a->i[row] + shift;
1294     if (*nz && shift) {
1295       *idx = (int *) PetscMalloc( (*nz)*sizeof(int) ); CHKPTRQ(*idx);
1296       for ( i=0; i<(*nz); i++ ) {(*idx)[i] = itmp[i] + shift;}
1297     } else if (*nz) {
1298       *idx = itmp;
1299     }
1300     else *idx = 0;
1301   }
1302   PetscFunctionReturn(0);
1303 }
1304 
1305 #undef __FUNC__
1306 #define __FUNC__ "MatRestoreRow_SeqAIJ"
1307 int MatRestoreRow_SeqAIJ(Mat A,int row,int *nz,int **idx,Scalar **v)
1308 {
1309   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1310 
1311   PetscFunctionBegin;
1312   if (idx) {if (*idx && a->indexshift) PetscFree(*idx);}
1313   PetscFunctionReturn(0);
1314 }
1315 
1316 #undef __FUNC__
1317 #define __FUNC__ "MatNorm_SeqAIJ"
1318 int MatNorm_SeqAIJ(Mat A,NormType type,double *norm)
1319 {
1320   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1321   Scalar     *v = a->a;
1322   double     sum = 0.0;
1323   int        i, j,shift = a->indexshift;
1324 
1325   PetscFunctionBegin;
1326   if (type == NORM_FROBENIUS) {
1327     for (i=0; i<a->nz; i++ ) {
1328 #if defined(USE_PETSC_COMPLEX)
1329       sum += PetscReal(PetscConj(*v)*(*v)); v++;
1330 #else
1331       sum += (*v)*(*v); v++;
1332 #endif
1333     }
1334     *norm = sqrt(sum);
1335   } else if (type == NORM_1) {
1336     double *tmp;
1337     int    *jj = a->j;
1338     tmp = (double *) PetscMalloc( (a->n+1)*sizeof(double) ); CHKPTRQ(tmp);
1339     PetscMemzero(tmp,a->n*sizeof(double));
1340     *norm = 0.0;
1341     for ( j=0; j<a->nz; j++ ) {
1342         tmp[*jj++ + shift] += PetscAbsScalar(*v);  v++;
1343     }
1344     for ( j=0; j<a->n; j++ ) {
1345       if (tmp[j] > *norm) *norm = tmp[j];
1346     }
1347     PetscFree(tmp);
1348   } else if (type == NORM_INFINITY) {
1349     *norm = 0.0;
1350     for ( j=0; j<a->m; j++ ) {
1351       v = a->a + a->i[j] + shift;
1352       sum = 0.0;
1353       for ( i=0; i<a->i[j+1]-a->i[j]; i++ ) {
1354         sum += PetscAbsScalar(*v); v++;
1355       }
1356       if (sum > *norm) *norm = sum;
1357     }
1358   } else {
1359     SETERRQ(PETSC_ERR_SUP,0,"No support for two norm");
1360   }
1361   PetscFunctionReturn(0);
1362 }
1363 
1364 #undef __FUNC__
1365 #define __FUNC__ "MatTranspose_SeqAIJ"
1366 int MatTranspose_SeqAIJ(Mat A,Mat *B)
1367 {
1368   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1369   Mat        C;
1370   int        i, ierr, *aj = a->j, *ai = a->i, m = a->m, len, *col;
1371   int        shift = a->indexshift;
1372   Scalar     *array = a->a;
1373 
1374   PetscFunctionBegin;
1375   if (B == PETSC_NULL && m != a->n) SETERRQ(PETSC_ERR_ARG_SIZ,0,"Square matrix only for in-place");
1376   col = (int *) PetscMalloc((1+a->n)*sizeof(int)); CHKPTRQ(col);
1377   PetscMemzero(col,(1+a->n)*sizeof(int));
1378   if (shift) {
1379     for ( i=0; i<ai[m]-1; i++ ) aj[i] -= 1;
1380   }
1381   for ( i=0; i<ai[m]+shift; i++ ) col[aj[i]] += 1;
1382   ierr = MatCreateSeqAIJ(A->comm,a->n,m,0,col,&C); CHKERRQ(ierr);
1383   PetscFree(col);
1384   for ( i=0; i<m; i++ ) {
1385     len = ai[i+1]-ai[i];
1386     ierr = MatSetValues(C,len,aj,1,&i,array,INSERT_VALUES); CHKERRQ(ierr);
1387     array += len; aj += len;
1388   }
1389   if (shift) {
1390     for ( i=0; i<ai[m]-1; i++ ) aj[i] += 1;
1391   }
1392 
1393   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
1394   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
1395 
1396   if (B != PETSC_NULL) {
1397     *B = C;
1398   } else {
1399     PetscOps *Abops;
1400     MatOps   Aops;
1401 
1402     /* This isn't really an in-place transpose */
1403     PetscFree(a->a);
1404     if (!a->singlemalloc) {PetscFree(a->i); PetscFree(a->j);}
1405     if (a->diag) PetscFree(a->diag);
1406     if (a->ilen) PetscFree(a->ilen);
1407     if (a->imax) PetscFree(a->imax);
1408     if (a->solve_work) PetscFree(a->solve_work);
1409     if (a->inode.size) PetscFree(a->inode.size);
1410     PetscFree(a);
1411 
1412 
1413     ierr = MapDestroy(A->rmap);CHKERRQ(ierr);
1414     ierr = MapDestroy(A->cmap);CHKERRQ(ierr);
1415 
1416     /*
1417       This is horrible, horrible code. We need to keep the
1418       the bops and ops Structures, copy everything from C
1419       including the function pointers..
1420     */
1421     PetscMemcpy(A->ops,C->ops,sizeof(struct _MatOps));
1422     PetscMemcpy(A->bops,C->bops,sizeof(PetscOps));
1423     Abops    = A->bops;
1424     Aops     = A->ops;
1425     PetscMemcpy(A,C,sizeof(struct _p_Mat));
1426     A->bops  = Abops;
1427     A->ops   = Aops;
1428     A->qlist = 0;
1429 
1430     PetscHeaderDestroy(C);
1431   }
1432   PetscFunctionReturn(0);
1433 }
1434 
1435 #undef __FUNC__
1436 #define __FUNC__ "MatDiagonalScale_SeqAIJ"
1437 int MatDiagonalScale_SeqAIJ(Mat A,Vec ll,Vec rr)
1438 {
1439   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1440   Scalar     *l,*r,x,*v;
1441   int        ierr,i,j,m = a->m, n = a->n, M, nz = a->nz, *jj,shift = a->indexshift;
1442 
1443   PetscFunctionBegin;
1444   if (ll) {
1445     /* The local size is used so that VecMPI can be passed to this routine
1446        by MatDiagonalScale_MPIAIJ */
1447     ierr = VecGetLocalSize(ll,&m);CHKERRQ(ierr);
1448     if (m != a->m) SETERRQ(PETSC_ERR_ARG_SIZ,0,"Left scaling vector wrong length");
1449     ierr = VecGetArray(ll,&l); CHKERRQ(ierr);
1450     v = a->a;
1451     for ( i=0; i<m; i++ ) {
1452       x = l[i];
1453       M = a->i[i+1] - a->i[i];
1454       for ( j=0; j<M; j++ ) { (*v++) *= x;}
1455     }
1456     ierr = VecRestoreArray(ll,&l); CHKERRQ(ierr);
1457     PLogFlops(nz);
1458   }
1459   if (rr) {
1460     ierr = VecGetLocalSize(rr,&n);CHKERRQ(ierr);
1461     if (n != a->n) SETERRQ(PETSC_ERR_ARG_SIZ,0,"Right scaling vector wrong length");
1462     ierr = VecGetArray(rr,&r);CHKERRQ(ierr);
1463     v = a->a; jj = a->j;
1464     for ( i=0; i<nz; i++ ) {
1465       (*v++) *= r[*jj++ + shift];
1466     }
1467     ierr = VecRestoreArray(rr,&r);CHKERRQ(ierr);
1468     PLogFlops(nz);
1469   }
1470   PetscFunctionReturn(0);
1471 }
1472 
1473 #undef __FUNC__
1474 #define __FUNC__ "MatGetSubMatrix_SeqAIJ"
1475 int MatGetSubMatrix_SeqAIJ(Mat A,IS isrow,IS iscol,int csize,MatReuse scall,Mat *B)
1476 {
1477   Mat_SeqAIJ   *a = (Mat_SeqAIJ *) A->data,*c;
1478   int          *smap, i, k, kstart, kend, ierr, oldcols = a->n,*lens;
1479   int          row,mat_i,*mat_j,tcol,first,step,*mat_ilen;
1480   register int sum,lensi;
1481   int          *irow, *icol, nrows, ncols, shift = a->indexshift,*ssmap;
1482   int          *starts,*j_new,*i_new,*aj = a->j, *ai = a->i,ii,*ailen = a->ilen;
1483   Scalar       *a_new,*mat_a;
1484   Mat          C;
1485   PetscTruth   stride;
1486 
1487   PetscFunctionBegin;
1488   ierr = ISSorted(isrow,(PetscTruth*)&i);CHKERRQ(ierr);
1489   if (!i) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,0,"ISrow is not sorted");
1490   ierr = ISSorted(iscol,(PetscTruth*)&i);CHKERRQ(ierr);
1491   if (!i) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,0,"IScol is not sorted");
1492 
1493   ierr = ISGetIndices(isrow,&irow); CHKERRQ(ierr);
1494   ierr = ISGetSize(isrow,&nrows); CHKERRQ(ierr);
1495   ierr = ISGetSize(iscol,&ncols); CHKERRQ(ierr);
1496 
1497   ierr = ISStrideGetInfo(iscol,&first,&step); CHKERRQ(ierr);
1498   ierr = ISStride(iscol,&stride); CHKERRQ(ierr);
1499   if (stride && step == 1) {
1500     /* special case of contiguous rows */
1501     lens   = (int *) PetscMalloc((ncols+nrows+1)*sizeof(int)); CHKPTRQ(lens);
1502     starts = lens + ncols;
1503     /* loop over new rows determining lens and starting points */
1504     for (i=0; i<nrows; i++) {
1505       kstart  = ai[irow[i]]+shift;
1506       kend    = kstart + ailen[irow[i]];
1507       for ( k=kstart; k<kend; k++ ) {
1508         if (aj[k]+shift >= first) {
1509           starts[i] = k;
1510           break;
1511 	}
1512       }
1513       sum = 0;
1514       while (k < kend) {
1515         if (aj[k++]+shift >= first+ncols) break;
1516         sum++;
1517       }
1518       lens[i] = sum;
1519     }
1520     /* create submatrix */
1521     if (scall == MAT_REUSE_MATRIX) {
1522       int n_cols,n_rows;
1523       ierr = MatGetSize(*B,&n_rows,&n_cols); CHKERRQ(ierr);
1524       if (n_rows != nrows || n_cols != ncols) SETERRQ(PETSC_ERR_ARG_SIZ,0,"Reused submatrix wrong size");
1525       ierr = MatZeroEntries(*B); CHKERRQ(ierr);
1526       C = *B;
1527     } else {
1528       ierr = MatCreateSeqAIJ(A->comm,nrows,ncols,0,lens,&C);CHKERRQ(ierr);
1529     }
1530     c = (Mat_SeqAIJ*) C->data;
1531 
1532     /* loop over rows inserting into submatrix */
1533     a_new    = c->a;
1534     j_new    = c->j;
1535     i_new    = c->i;
1536     i_new[0] = -shift;
1537     for (i=0; i<nrows; i++) {
1538       ii    = starts[i];
1539       lensi = lens[i];
1540       for ( k=0; k<lensi; k++ ) {
1541         *j_new++ = aj[ii+k] - first;
1542       }
1543       PetscMemcpy(a_new,a->a + starts[i],lensi*sizeof(Scalar));
1544       a_new      += lensi;
1545       i_new[i+1]  = i_new[i] + lensi;
1546       c->ilen[i]  = lensi;
1547     }
1548     PetscFree(lens);
1549   } else {
1550     ierr = ISGetIndices(iscol,&icol); CHKERRQ(ierr);
1551     smap  = (int *) PetscMalloc((1+oldcols)*sizeof(int)); CHKPTRQ(smap);
1552     ssmap = smap + shift;
1553     lens  = (int *) PetscMalloc((1+nrows)*sizeof(int)); CHKPTRQ(lens);
1554     PetscMemzero(smap,oldcols*sizeof(int));
1555     for ( i=0; i<ncols; i++ ) smap[icol[i]] = i+1;
1556     /* determine lens of each row */
1557     for (i=0; i<nrows; i++) {
1558       kstart  = ai[irow[i]]+shift;
1559       kend    = kstart + a->ilen[irow[i]];
1560       lens[i] = 0;
1561       for ( k=kstart; k<kend; k++ ) {
1562         if (ssmap[aj[k]]) {
1563           lens[i]++;
1564         }
1565       }
1566     }
1567     /* Create and fill new matrix */
1568     if (scall == MAT_REUSE_MATRIX) {
1569       c = (Mat_SeqAIJ *)((*B)->data);
1570       if (c->m  != nrows || c->n != ncols) SETERRQ(PETSC_ERR_ARG_SIZ,0,"Cannot reuse matrix. wrong size");
1571       if (PetscMemcmp(c->ilen,lens, c->m *sizeof(int))) {
1572         SETERRQ(PETSC_ERR_ARG_SIZ,0,"Cannot reuse matrix. wrong no of nonzeros");
1573       }
1574       PetscMemzero(c->ilen,c->m*sizeof(int));
1575       C = *B;
1576     } else {
1577       ierr = MatCreateSeqAIJ(A->comm,nrows,ncols,0,lens,&C);CHKERRQ(ierr);
1578     }
1579     c = (Mat_SeqAIJ *)(C->data);
1580     for (i=0; i<nrows; i++) {
1581       row    = irow[i];
1582       kstart = ai[row]+shift;
1583       kend   = kstart + a->ilen[row];
1584       mat_i  = c->i[i]+shift;
1585       mat_j  = c->j + mat_i;
1586       mat_a  = c->a + mat_i;
1587       mat_ilen = c->ilen + i;
1588       for ( k=kstart; k<kend; k++ ) {
1589         if ((tcol=ssmap[a->j[k]])) {
1590           *mat_j++ = tcol - (!shift);
1591           *mat_a++ = a->a[k];
1592           (*mat_ilen)++;
1593 
1594         }
1595       }
1596     }
1597     /* Free work space */
1598     ierr = ISRestoreIndices(iscol,&icol); CHKERRQ(ierr);
1599     PetscFree(smap); PetscFree(lens);
1600   }
1601   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
1602   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
1603 
1604   ierr = ISRestoreIndices(isrow,&irow); CHKERRQ(ierr);
1605   *B = C;
1606   PetscFunctionReturn(0);
1607 }
1608 
1609 /*
1610      note: This can only work for identity for row and col. It would
1611    be good to check this and otherwise generate an error.
1612 */
1613 #undef __FUNC__
1614 #define __FUNC__ "MatILUFactor_SeqAIJ"
1615 int MatILUFactor_SeqAIJ(Mat inA,IS row,IS col,MatILUInfo *info)
1616 {
1617   Mat_SeqAIJ *a = (Mat_SeqAIJ *) inA->data;
1618   int        ierr;
1619   Mat        outA;
1620 
1621   PetscFunctionBegin;
1622   if (info && info->levels != 0) SETERRQ(PETSC_ERR_SUP,0,"Only levels=0 supported");
1623 
1624   outA          = inA;
1625   inA->factor   = FACTOR_LU;
1626   a->row        = row;
1627   a->col        = col;
1628 
1629   /* Create the invert permutation so that it can be used in MatLUFactorNumeric() */
1630   ierr = ISInvertPermutation(col,&(a->icol)); CHKERRQ(ierr);
1631   PLogObjectParent(inA,a->icol);
1632 
1633   if (!a->solve_work) { /* this matrix may have been factored before */
1634     a->solve_work = (Scalar *) PetscMalloc( (a->m+1)*sizeof(Scalar));CHKPTRQ(a->solve_work);
1635   }
1636 
1637   if (!a->diag) {
1638     ierr = MatMarkDiag_SeqAIJ(inA); CHKERRQ(ierr);
1639   }
1640   ierr = MatLUFactorNumeric_SeqAIJ(inA,&outA); CHKERRQ(ierr);
1641   PetscFunctionReturn(0);
1642 }
1643 
1644 #include "pinclude/blaslapack.h"
1645 #undef __FUNC__
1646 #define __FUNC__ "MatScale_SeqAIJ"
1647 int MatScale_SeqAIJ(Scalar *alpha,Mat inA)
1648 {
1649   Mat_SeqAIJ *a = (Mat_SeqAIJ *) inA->data;
1650   int        one = 1;
1651 
1652   PetscFunctionBegin;
1653   BLscal_( &a->nz, alpha, a->a, &one );
1654   PLogFlops(a->nz);
1655   PetscFunctionReturn(0);
1656 }
1657 
1658 #undef __FUNC__
1659 #define __FUNC__ "MatGetSubMatrices_SeqAIJ"
1660 int MatGetSubMatrices_SeqAIJ(Mat A,int n, IS *irow,IS *icol,MatReuse scall,Mat **B)
1661 {
1662   int ierr,i;
1663 
1664   PetscFunctionBegin;
1665   if (scall == MAT_INITIAL_MATRIX) {
1666     *B = (Mat *) PetscMalloc( (n+1)*sizeof(Mat) ); CHKPTRQ(*B);
1667   }
1668 
1669   for ( i=0; i<n; i++ ) {
1670     ierr = MatGetSubMatrix_SeqAIJ(A,irow[i],icol[i],PETSC_DECIDE,scall,&(*B)[i]);CHKERRQ(ierr);
1671   }
1672   PetscFunctionReturn(0);
1673 }
1674 
1675 #undef __FUNC__
1676 #define __FUNC__ "MatGetBlockSize_SeqAIJ"
1677 int MatGetBlockSize_SeqAIJ(Mat A, int *bs)
1678 {
1679   PetscFunctionBegin;
1680   *bs = 1;
1681   PetscFunctionReturn(0);
1682 }
1683 
1684 #undef __FUNC__
1685 #define __FUNC__ "MatIncreaseOverlap_SeqAIJ"
1686 int MatIncreaseOverlap_SeqAIJ(Mat A, int is_max, IS *is, int ov)
1687 {
1688   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1689   int        shift, row, i,j,k,l,m,n, *idx,ierr, *nidx, isz, val;
1690   int        start, end, *ai, *aj;
1691   BT         table;
1692 
1693   PetscFunctionBegin;
1694   shift = a->indexshift;
1695   m     = a->m;
1696   ai    = a->i;
1697   aj    = a->j+shift;
1698 
1699   if (ov < 0)  SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"illegal overlap value used");
1700 
1701   nidx  = (int *) PetscMalloc((m+1)*sizeof(int)); CHKPTRQ(nidx);
1702   ierr  = BTCreate(m,table); CHKERRQ(ierr);
1703 
1704   for ( i=0; i<is_max; i++ ) {
1705     /* Initialize the two local arrays */
1706     isz  = 0;
1707     BTMemzero(m,table);
1708 
1709     /* Extract the indices, assume there can be duplicate entries */
1710     ierr = ISGetIndices(is[i],&idx);  CHKERRQ(ierr);
1711     ierr = ISGetSize(is[i],&n);  CHKERRQ(ierr);
1712 
1713     /* Enter these into the temp arrays. I.e., mark table[row], enter row into new index */
1714     for ( j=0; j<n ; ++j){
1715       if(!BTLookupSet(table, idx[j])) { nidx[isz++] = idx[j];}
1716     }
1717     ierr = ISRestoreIndices(is[i],&idx);  CHKERRQ(ierr);
1718     ierr = ISDestroy(is[i]); CHKERRQ(ierr);
1719 
1720     k = 0;
1721     for ( j=0; j<ov; j++){ /* for each overlap */
1722       n = isz;
1723       for ( ; k<n ; k++){ /* do only those rows in nidx[k], which are not done yet */
1724         row   = nidx[k];
1725         start = ai[row];
1726         end   = ai[row+1];
1727         for ( l = start; l<end ; l++){
1728           val = aj[l] + shift;
1729           if (!BTLookupSet(table,val)) {nidx[isz++] = val;}
1730         }
1731       }
1732     }
1733     ierr = ISCreateGeneral(PETSC_COMM_SELF, isz, nidx, (is+i)); CHKERRQ(ierr);
1734   }
1735   BTDestroy(table);
1736   PetscFree(nidx);
1737   PetscFunctionReturn(0);
1738 }
1739 
1740 /* -------------------------------------------------------------- */
1741 #undef __FUNC__
1742 #define __FUNC__ "MatPermute_SeqAIJ"
1743 int MatPermute_SeqAIJ(Mat A, IS rowp, IS colp, Mat *B)
1744 {
1745   Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1746   Scalar     *vwork;
1747   int        i, ierr, nz, m = a->m, n = a->n, *cwork;
1748   int        *row,*col,*cnew,j,*lens;
1749   IS         icolp,irowp;
1750 
1751   PetscFunctionBegin;
1752   ierr = ISInvertPermutation(rowp,&irowp); CHKERRQ(ierr);
1753   ierr = ISGetIndices(irowp,&row); CHKERRQ(ierr);
1754   ierr = ISInvertPermutation(colp,&icolp); CHKERRQ(ierr);
1755   ierr = ISGetIndices(icolp,&col); CHKERRQ(ierr);
1756 
1757   /* determine lengths of permuted rows */
1758   lens = (int *) PetscMalloc( (m+1)*sizeof(int) ); CHKPTRQ(lens);
1759   for (i=0; i<m; i++ ) {
1760     lens[row[i]] = a->i[i+1] - a->i[i];
1761   }
1762   ierr = MatCreateSeqAIJ(A->comm,m,n,0,lens,B);CHKERRQ(ierr);
1763   PetscFree(lens);
1764 
1765   cnew = (int *) PetscMalloc( n*sizeof(int) ); CHKPTRQ(cnew);
1766   for (i=0; i<m; i++) {
1767     ierr = MatGetRow(A,i,&nz,&cwork,&vwork); CHKERRQ(ierr);
1768     for (j=0; j<nz; j++ ) { cnew[j] = col[cwork[j]];}
1769     ierr = MatSetValues(*B,1,&row[i],nz,cnew,vwork,INSERT_VALUES); CHKERRQ(ierr);
1770     ierr = MatRestoreRow(A,i,&nz,&cwork,&vwork); CHKERRQ(ierr);
1771   }
1772   PetscFree(cnew);
1773   ierr = MatAssemblyBegin(*B,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
1774   ierr = MatAssemblyEnd(*B,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
1775   ierr = ISRestoreIndices(irowp,&row); CHKERRQ(ierr);
1776   ierr = ISRestoreIndices(icolp,&col); CHKERRQ(ierr);
1777   ierr = ISDestroy(irowp); CHKERRQ(ierr);
1778   ierr = ISDestroy(icolp); CHKERRQ(ierr);
1779   PetscFunctionReturn(0);
1780 }
1781 
1782 #undef __FUNC__
1783 #define __FUNC__ "MatPrintHelp_SeqAIJ"
1784 int MatPrintHelp_SeqAIJ(Mat A)
1785 {
1786   static int called = 0;
1787   MPI_Comm   comm = A->comm;
1788   int        ierr;
1789 
1790   PetscFunctionBegin;
1791   if (called) {PetscFunctionReturn(0);} else called = 1;
1792   ierr = (*PetscHelpPrintf)(comm," Options for MATSEQAIJ and MATMPIAIJ matrix formats (the defaults):\n");CHKERRQ(ierr);
1793   ierr = (*PetscHelpPrintf)(comm,"  -mat_lu_pivotthreshold <threshold>: Set pivoting threshold\n");CHKERRQ(ierr);
1794   ierr = (*PetscHelpPrintf)(comm,"  -mat_aij_oneindex: internal indices begin at 1 instead of the default 0.\n");CHKERRQ(ierr);
1795   ierr = (*PetscHelpPrintf)(comm,"  -mat_aij_no_inode: Do not use inodes\n");CHKERRQ(ierr);
1796   ierr = (*PetscHelpPrintf)(comm,"  -mat_aij_inode_limit <limit>: Set inode limit (max limit=5)\n");CHKERRQ(ierr);
1797 #if defined(HAVE_ESSL)
1798   ierr = (*PetscHelpPrintf)(comm,"  -mat_aij_essl: Use IBM sparse LU factorization and solve.\n");CHKERRQ(ierr);
1799 #endif
1800   PetscFunctionReturn(0);
1801 }
1802 extern int MatEqual_SeqAIJ(Mat A,Mat B, PetscTruth* flg);
1803 extern int MatFDColoringCreate_SeqAIJ(Mat,ISColoring,MatFDColoring);
1804 extern int MatColoringPatch_SeqAIJ(Mat,int,int *,ISColoring *);
1805 
1806 #undef __FUNC__
1807 #define __FUNC__ "MatCopy_SeqAIJ"
1808 int MatCopy_SeqAIJ(Mat A,Mat B,MatStructure str)
1809 {
1810   int    ierr;
1811 
1812   PetscFunctionBegin;
1813   if (str == SAME_NONZERO_PATTERN && B->type == MATSEQAIJ) {
1814     Mat_SeqAIJ *a = (Mat_SeqAIJ *) A->data;
1815     Mat_SeqAIJ *b = (Mat_SeqAIJ *) B->data;
1816 
1817     if (a->i[a->m]+a->indexshift != b->i[b->m]+a->indexshift) {
1818       SETERRQ(1,1,"Number of nonzeros in two matrices are different");
1819     }
1820     PetscMemcpy(b->a,a->a,(a->i[a->m]+a->indexshift)*sizeof(Scalar));
1821   } else {
1822     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
1823   }
1824   PetscFunctionReturn(0);
1825 }
1826 
1827 /* -------------------------------------------------------------------*/
1828 static struct _MatOps MatOps_Values = {MatSetValues_SeqAIJ,
1829        MatGetRow_SeqAIJ,
1830        MatRestoreRow_SeqAIJ,
1831        MatMult_SeqAIJ,
1832        MatMultAdd_SeqAIJ,
1833        MatMultTrans_SeqAIJ,
1834        MatMultTransAdd_SeqAIJ,
1835        MatSolve_SeqAIJ,
1836        MatSolveAdd_SeqAIJ,
1837        MatSolveTrans_SeqAIJ,
1838        MatSolveTransAdd_SeqAIJ,
1839        MatLUFactor_SeqAIJ,
1840        0,
1841        MatRelax_SeqAIJ,
1842        MatTranspose_SeqAIJ,
1843        MatGetInfo_SeqAIJ,
1844        MatEqual_SeqAIJ,
1845        MatGetDiagonal_SeqAIJ,
1846        MatDiagonalScale_SeqAIJ,
1847        MatNorm_SeqAIJ,
1848        0,
1849        MatAssemblyEnd_SeqAIJ,
1850        MatCompress_SeqAIJ,
1851        MatSetOption_SeqAIJ,
1852        MatZeroEntries_SeqAIJ,
1853        MatZeroRows_SeqAIJ,
1854        MatLUFactorSymbolic_SeqAIJ,
1855        MatLUFactorNumeric_SeqAIJ,
1856        0,
1857        0,
1858        MatGetSize_SeqAIJ,
1859        MatGetSize_SeqAIJ,
1860        MatGetOwnershipRange_SeqAIJ,
1861        MatILUFactorSymbolic_SeqAIJ,
1862        0,
1863        0,
1864        0,
1865        MatDuplicate_SeqAIJ,
1866        0,
1867        0,
1868        MatILUFactor_SeqAIJ,
1869        0,
1870        0,
1871        MatGetSubMatrices_SeqAIJ,
1872        MatIncreaseOverlap_SeqAIJ,
1873        MatGetValues_SeqAIJ,
1874        MatCopy_SeqAIJ,
1875        MatPrintHelp_SeqAIJ,
1876        MatScale_SeqAIJ,
1877        0,
1878        0,
1879        MatILUDTFactor_SeqAIJ,
1880        MatGetBlockSize_SeqAIJ,
1881        MatGetRowIJ_SeqAIJ,
1882        MatRestoreRowIJ_SeqAIJ,
1883        MatGetColumnIJ_SeqAIJ,
1884        MatRestoreColumnIJ_SeqAIJ,
1885        MatFDColoringCreate_SeqAIJ,
1886        MatColoringPatch_SeqAIJ,
1887        0,
1888        MatPermute_SeqAIJ,
1889        0,
1890        0,
1891        0,
1892        0,
1893        MatGetMaps_Petsc};
1894 
1895 extern int MatUseSuperLU_SeqAIJ(Mat);
1896 extern int MatUseEssl_SeqAIJ(Mat);
1897 extern int MatUseDXML_SeqAIJ(Mat);
1898 
1899 EXTERN_C_BEGIN
1900 #undef __FUNC__
1901 #define __FUNC__ "MatSeqAIJSetColumnIndices_SeqAIJ"
1902 
1903 int MatSeqAIJSetColumnIndices_SeqAIJ(Mat mat,int *indices)
1904 {
1905   Mat_SeqAIJ *aij = (Mat_SeqAIJ *)mat->data;
1906   int        i,nz,n;
1907 
1908   PetscFunctionBegin;
1909   if (aij->indexshift) SETERRQ(1,1,"No support with 1 based indexing");
1910 
1911   nz = aij->maxnz;
1912   n  = aij->n;
1913   for (i=0; i<nz; i++) {
1914     aij->j[i] = indices[i];
1915   }
1916   aij->nz = nz;
1917   for ( i=0; i<n; i++ ) {
1918     aij->ilen[i] = aij->imax[i];
1919   }
1920 
1921   PetscFunctionReturn(0);
1922 }
1923 EXTERN_C_END
1924 
1925 #undef __FUNC__
1926 #define __FUNC__ "MatSeqAIJSetColumnIndices"
1927 /*@
1928     MatSeqAIJSetColumnIndices - Set the column indices for all the rows
1929        in the matrix.
1930 
1931   Input Parameters:
1932 +  mat - the SeqAIJ matrix
1933 -  indices - the column indices
1934 
1935   Level: advanced
1936 
1937   Notes:
1938     This can be called if you have precomputed the nonzero structure of the
1939   matrix and want to provide it to the matrix object to improve the performance
1940   of the MatSetValues() operation.
1941 
1942     You MUST have set the correct numbers of nonzeros per row in the call to
1943   MatCreateSeqAIJ().
1944 
1945     MUST be called before any calls to MatSetValues();
1946 
1947 @*/
1948 int MatSeqAIJSetColumnIndices(Mat mat,int *indices)
1949 {
1950   int ierr,(*f)(Mat,int *);
1951 
1952   PetscFunctionBegin;
1953   PetscValidHeaderSpecific(mat,MAT_COOKIE);
1954   ierr = PetscObjectQueryFunction((PetscObject)mat,"MatSeqAIJSetColumnIndices_C",(void **)&f);
1955          CHKERRQ(ierr);
1956   if (f) {
1957     ierr = (*f)(mat,indices);CHKERRQ(ierr);
1958   } else {
1959     SETERRQ(1,1,"Wrong type of matrix to set column indices");
1960   }
1961   PetscFunctionReturn(0);
1962 }
1963 
1964 /* ----------------------------------------------------------------------------------------*/
1965 
1966 EXTERN_C_BEGIN
1967 #undef __FUNC__
1968 #define __FUNC__ "MatStoreValues_SeqAIJ"
1969 int MatStoreValues_SeqAIJ(Mat mat)
1970 {
1971   Mat_SeqAIJ *aij = (Mat_SeqAIJ *)mat->data;
1972   int        nz = aij->i[aij->m]+aij->indexshift;
1973 
1974   PetscFunctionBegin;
1975   if (aij->nonew != 1) {
1976     SETERRQ(1,1,"Must call MatSetOption(A,MAT_NO_NEW_NONZERO_LOCATIONS);first");
1977   }
1978 
1979   /* allocate space for values if not already there */
1980   if (!aij->saved_values) {
1981     aij->saved_values = (Scalar *) PetscMalloc(nz*sizeof(Scalar));CHKPTRQ(aij->saved_values);
1982   }
1983 
1984   /* copy values over */
1985   PetscMemcpy(aij->saved_values,aij->a,nz*sizeof(Scalar));
1986   PetscFunctionReturn(0);
1987 }
1988 EXTERN_C_END
1989 
1990 #undef __FUNC__
1991 #define __FUNC__ "MatStoreValues"
1992 /*@
1993     MatStoreValues - Stashes a copy of the matrix values; this allows, for
1994        example, reuse of the linear part of a Jacobian, while recomputing the
1995        nonlinear portion.
1996 
1997    Collect on Mat
1998 
1999   Input Parameters:
2000 .  mat - the matrix (currently on AIJ matrices support this option)
2001 
2002   Level: advanced
2003 
2004   Common Usage, with SNESSolve():
2005 $    Create Jacobian matrix
2006 $    Set linear terms into matrix
2007 $    Apply boundary conditions to matrix, at this time matrix must have
2008 $      final nonzero structure (i.e. setting the nonlinear terms and applying
2009 $      boundary conditions again will not change the nonzero structure
2010 $    ierr = MatSetOption(mat,MAT_NO_NEW_NONZERO_LOCATIONS);
2011 $    ierr = MatStoreValues(mat);
2012 $    Call SNESSetJacobian() with matrix
2013 $    In your Jacobian routine
2014 $      ierr = MatRetrieveValues(mat);
2015 $      Set nonlinear terms in matrix
2016 
2017   Common Usage without SNESSolve(), i.e. when you handle nonlinear solve yourself:
2018 $    // build linear portion of Jacobian
2019 $    ierr = MatSetOption(mat,MAT_NO_NEW_NONZERO_LOCATIONS);
2020 $    ierr = MatStoreValues(mat);
2021 $    loop over nonlinear iterations
2022 $       ierr = MatRetrieveValues(mat);
2023 $       // call MatSetValues(mat,...) to set nonliner portion of Jacobian
2024 $       // call MatAssemblyBegin/End() on matrix
2025 $       Solve linear system with Jacobian
2026 $    endloop
2027 
2028   Notes:
2029     Matrix must already be assemblied before calling this routine
2030     Must set the matrix option MatSetOption(mat,MAT_NO_NEW_NONZERO_LOCATIONS); before
2031     calling this routine.
2032 
2033 .seealso: MatRetrieveValues()
2034 
2035 @*/
2036 int MatStoreValues(Mat mat)
2037 {
2038   int ierr,(*f)(Mat);
2039 
2040   PetscFunctionBegin;
2041   PetscValidHeaderSpecific(mat,MAT_COOKIE);
2042   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,0,"Not for unassembled matrix");
2043   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,0,"Not for factored matrix");
2044 
2045   ierr = PetscObjectQueryFunction((PetscObject)mat,"MatStoreValues_C",(void **)&f);CHKERRQ(ierr);
2046   if (f) {
2047     ierr = (*f)(mat);CHKERRQ(ierr);
2048   } else {
2049     SETERRQ(1,1,"Wrong type of matrix to store values");
2050   }
2051   PetscFunctionReturn(0);
2052 }
2053 
2054 EXTERN_C_BEGIN
2055 #undef __FUNC__
2056 #define __FUNC__ "MatRetrieveValues_SeqAIJ"
2057 int MatRetrieveValues_SeqAIJ(Mat mat)
2058 {
2059   Mat_SeqAIJ *aij = (Mat_SeqAIJ *)mat->data;
2060   int        nz = aij->i[aij->m]+aij->indexshift;
2061 
2062   PetscFunctionBegin;
2063   if (aij->nonew != 1) {
2064     SETERRQ(1,1,"Must call MatSetOption(A,MAT_NO_NEW_NONZERO_LOCATIONS);first");
2065   }
2066   if (!aij->saved_values) {
2067     SETERRQ(1,1,"Must call MatStoreValues(A);first");
2068   }
2069 
2070   /* copy values over */
2071   PetscMemcpy(aij->a, aij->saved_values,nz*sizeof(Scalar));
2072   PetscFunctionReturn(0);
2073 }
2074 EXTERN_C_END
2075 
2076 #undef __FUNC__
2077 #define __FUNC__ "MatRetrieveValues"
2078 /*@
2079     MatRetrieveValues - Retrieves the copy of the matrix values; this allows, for
2080        example, reuse of the linear part of a Jacobian, while recomputing the
2081        nonlinear portion.
2082 
2083    Collect on Mat
2084 
2085   Input Parameters:
2086 .  mat - the matrix (currently on AIJ matrices support this option)
2087 
2088   Level: advanced
2089 
2090 .seealso: MatStoreValues()
2091 
2092 @*/
2093 int MatRetrieveValues(Mat mat)
2094 {
2095   int ierr,(*f)(Mat);
2096 
2097   PetscFunctionBegin;
2098   PetscValidHeaderSpecific(mat,MAT_COOKIE);
2099   if (!mat->assembled) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,0,"Not for unassembled matrix");
2100   if (mat->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,0,"Not for factored matrix");
2101 
2102   ierr = PetscObjectQueryFunction((PetscObject)mat,"MatRetrieveValues_C",(void **)&f);CHKERRQ(ierr);
2103   if (f) {
2104     ierr = (*f)(mat);CHKERRQ(ierr);
2105   } else {
2106     SETERRQ(1,1,"Wrong type of matrix to retrieve values");
2107   }
2108   PetscFunctionReturn(0);
2109 }
2110 
2111 /* --------------------------------------------------------------------------------*/
2112 
2113 #undef __FUNC__
2114 #define __FUNC__ "MatCreateSeqAIJ"
2115 /*@C
2116    MatCreateSeqAIJ - Creates a sparse matrix in AIJ (compressed row) format
2117    (the default parallel PETSc format).  For good matrix assembly performance
2118    the user should preallocate the matrix storage by setting the parameter nz
2119    (or the array nnz).  By setting these parameters accurately, performance
2120    during matrix assembly can be increased by more than a factor of 50.
2121 
2122    Collective on MPI_Comm
2123 
2124    Input Parameters:
2125 +  comm - MPI communicator, set to PETSC_COMM_SELF
2126 .  m - number of rows
2127 .  n - number of columns
2128 .  nz - number of nonzeros per row (same for all rows)
2129 -  nnz - array containing the number of nonzeros in the various rows
2130          (possibly different for each row) or PETSC_NULL
2131 
2132    Output Parameter:
2133 .  A - the matrix
2134 
2135    Notes:
2136    The AIJ format (also called the Yale sparse matrix format or
2137    compressed row storage), is fully compatible with standard Fortran 77
2138    storage.  That is, the stored row and column indices can begin at
2139    either one (as in Fortran) or zero.  See the users' manual for details.
2140 
2141    Specify the preallocated storage with either nz or nnz (not both).
2142    Set nz=PETSC_DEFAULT and nnz=PETSC_NULL for PETSc to control dynamic memory
2143    allocation.  For large problems you MUST preallocate memory or you
2144    will get TERRIBLE performance, see the users' manual chapter on matrices.
2145 
2146    By default, this format uses inodes (identical nodes) when possible, to
2147    improve numerical efficiency of matrix-vector products and solves. We
2148    search for consecutive rows with the same nonzero structure, thereby
2149    reusing matrix information to achieve increased efficiency.
2150 
2151    Options Database Keys:
2152 +  -mat_aij_no_inode  - Do not use inodes
2153 .  -mat_aij_inode_limit <limit> - Sets inode limit (max limit=5)
2154 -  -mat_aij_oneindex - Internally use indexing starting at 1
2155         rather than 0.  Note that when calling MatSetValues(),
2156         the user still MUST index entries starting at 0!
2157 
2158    Level: intermediate
2159 
2160 .seealso: MatCreate(), MatCreateMPIAIJ(), MatSetValues(), MatSeqAIJSetColumnIndices()
2161 @*/
2162 int MatCreateSeqAIJ(MPI_Comm comm,int m,int n,int nz,int *nnz, Mat *A)
2163 {
2164   Mat        B;
2165   Mat_SeqAIJ *b;
2166   int        i, len, ierr, flg,size;
2167 
2168   PetscFunctionBegin;
2169   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2170   if (size > 1) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,0,"Comm must be of size 1");
2171 
2172   *A                  = 0;
2173   PetscHeaderCreate(B,_p_Mat,struct _MatOps,MAT_COOKIE,MATSEQAIJ,"Mat",comm,MatDestroy,MatView);
2174   PLogObjectCreate(B);
2175   B->data             = (void *) (b = PetscNew(Mat_SeqAIJ)); CHKPTRQ(b);
2176   PetscMemzero(b,sizeof(Mat_SeqAIJ));
2177   PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));
2178   B->ops->destroy          = MatDestroy_SeqAIJ;
2179   B->ops->view             = MatView_SeqAIJ;
2180   B->factor           = 0;
2181   B->lupivotthreshold = 1.0;
2182   B->mapping          = 0;
2183   ierr = OptionsGetDouble(PETSC_NULL,"-mat_lu_pivotthreshold",&B->lupivotthreshold,&flg);CHKERRQ(ierr);
2184   b->ilu_preserve_row_sums = PETSC_FALSE;
2185   ierr = OptionsHasName(PETSC_NULL,"-pc_ilu_preserve_row_sums",(int*)&b->ilu_preserve_row_sums);CHKERRQ(ierr);
2186   b->row              = 0;
2187   b->col              = 0;
2188   b->icol             = 0;
2189   b->indexshift       = 0;
2190   b->reallocs         = 0;
2191   ierr = OptionsHasName(PETSC_NULL,"-mat_aij_oneindex", &flg); CHKERRQ(ierr);
2192   if (flg) b->indexshift = -1;
2193 
2194   b->m = m; B->m = m; B->M = m;
2195   b->n = n; B->n = n; B->N = n;
2196 
2197   ierr = MapCreateMPI(comm,m,m,&B->rmap);CHKERRQ(ierr);
2198   ierr = MapCreateMPI(comm,n,n,&B->cmap);CHKERRQ(ierr);
2199 
2200   b->imax = (int *) PetscMalloc( (m+1)*sizeof(int) ); CHKPTRQ(b->imax);
2201   if (nnz == PETSC_NULL) {
2202     if (nz == PETSC_DEFAULT) nz = 10;
2203     else if (nz <= 0)        nz = 1;
2204     for ( i=0; i<m; i++ ) b->imax[i] = nz;
2205     nz = nz*m;
2206   } else {
2207     nz = 0;
2208     for ( i=0; i<m; i++ ) {b->imax[i] = nnz[i]; nz += nnz[i];}
2209   }
2210 
2211   /* allocate the matrix space */
2212   len             = nz*(sizeof(int) + sizeof(Scalar)) + (b->m+1)*sizeof(int);
2213   b->a            = (Scalar *) PetscMalloc( len ); CHKPTRQ(b->a);
2214   b->j            = (int *) (b->a + nz);
2215   PetscMemzero(b->j,nz*sizeof(int));
2216   b->i            = b->j + nz;
2217   b->singlemalloc = 1;
2218 
2219   b->i[0] = -b->indexshift;
2220   for (i=1; i<m+1; i++) {
2221     b->i[i] = b->i[i-1] + b->imax[i-1];
2222   }
2223 
2224   /* b->ilen will count nonzeros in each row so far. */
2225   b->ilen = (int *) PetscMalloc((m+1)*sizeof(int));
2226   PLogObjectMemory(B,len+2*(m+1)*sizeof(int)+sizeof(struct _p_Mat)+sizeof(Mat_SeqAIJ));
2227   for ( i=0; i<b->m; i++ ) { b->ilen[i] = 0;}
2228 
2229   b->nz               = 0;
2230   b->maxnz            = nz;
2231   b->sorted           = 0;
2232   b->roworiented      = 1;
2233   b->nonew            = 0;
2234   b->diag             = 0;
2235   b->solve_work       = 0;
2236   b->spptr            = 0;
2237   b->inode.node_count = 0;
2238   b->inode.size       = 0;
2239   b->inode.limit      = 5;
2240   b->inode.max_limit  = 5;
2241   b->saved_values     = 0;
2242   B->info.nz_unneeded = (double)b->maxnz;
2243   b->idiag            = 0;
2244   b->ssor             = 0;
2245 
2246   *A = B;
2247 
2248   /*  SuperLU is not currently supported through PETSc */
2249 #if defined(HAVE_SUPERLU)
2250   ierr = OptionsHasName(PETSC_NULL,"-mat_aij_superlu", &flg); CHKERRQ(ierr);
2251   if (flg) { ierr = MatUseSuperLU_SeqAIJ(B); CHKERRQ(ierr); }
2252 #endif
2253   ierr = OptionsHasName(PETSC_NULL,"-mat_aij_essl", &flg); CHKERRQ(ierr);
2254   if (flg) { ierr = MatUseEssl_SeqAIJ(B); CHKERRQ(ierr); }
2255   ierr = OptionsHasName(PETSC_NULL,"-mat_aij_dxml", &flg); CHKERRQ(ierr);
2256   if (flg) {
2257     if (!b->indexshift) SETERRQ( PETSC_ERR_LIB,0,"need -mat_aij_oneindex with -mat_aij_dxml");
2258     ierr = MatUseDXML_SeqAIJ(B); CHKERRQ(ierr);
2259   }
2260   ierr = OptionsHasName(PETSC_NULL,"-help", &flg); CHKERRQ(ierr);
2261   if (flg) {ierr = MatPrintHelp(B); CHKERRQ(ierr); }
2262 
2263   ierr = PetscObjectComposeFunction((PetscObject)B,"MatSeqAIJSetColumnIndices_C",
2264                                      "MatSeqAIJSetColumnIndices_SeqAIJ",
2265                                      (void*)MatSeqAIJSetColumnIndices_SeqAIJ);CHKERRQ(ierr);
2266   ierr = PetscObjectComposeFunction((PetscObject)B,"MatStoreValues_C",
2267                                      "MatStoreValues_SeqAIJ",
2268                                      (void*)MatStoreValues_SeqAIJ);CHKERRQ(ierr);
2269   ierr = PetscObjectComposeFunction((PetscObject)B,"MatRetrieveValues_C",
2270                                      "MatRetrieveValues_SeqAIJ",
2271                                      (void*)MatRetrieveValues_SeqAIJ);CHKERRQ(ierr);
2272   PetscFunctionReturn(0);
2273 }
2274 
2275 #undef __FUNC__
2276 #define __FUNC__ "MatDuplicate_SeqAIJ"
2277 int MatDuplicate_SeqAIJ(Mat A,MatDuplicateOption cpvalues,Mat *B)
2278 {
2279   Mat        C;
2280   Mat_SeqAIJ *c,*a = (Mat_SeqAIJ *) A->data;
2281   int        i,len, m = a->m,shift = a->indexshift,ierr;
2282 
2283   PetscFunctionBegin;
2284   *B = 0;
2285   PetscHeaderCreate(C,_p_Mat,struct _MatOps,MAT_COOKIE,MATSEQAIJ,"Mat",A->comm,MatDestroy,MatView);
2286   PLogObjectCreate(C);
2287   C->data       = (void *) (c = PetscNew(Mat_SeqAIJ)); CHKPTRQ(c);
2288   PetscMemcpy(C->ops,A->ops,sizeof(struct _MatOps));
2289   C->ops->destroy = MatDestroy_SeqAIJ;
2290   C->ops->view    = MatView_SeqAIJ;
2291   C->factor       = A->factor;
2292   c->row          = 0;
2293   c->col          = 0;
2294   c->icol         = 0;
2295   c->indexshift   = shift;
2296   C->assembled    = PETSC_TRUE;
2297 
2298   c->m = C->m   = a->m;
2299   c->n = C->n   = a->n;
2300   C->M          = a->m;
2301   C->N          = a->n;
2302 
2303   c->imax       = (int *) PetscMalloc((m+1)*sizeof(int)); CHKPTRQ(c->imax);
2304   c->ilen       = (int *) PetscMalloc((m+1)*sizeof(int)); CHKPTRQ(c->ilen);
2305   for ( i=0; i<m; i++ ) {
2306     c->imax[i] = a->imax[i];
2307     c->ilen[i] = a->ilen[i];
2308   }
2309 
2310   /* allocate the matrix space */
2311   c->singlemalloc = 1;
2312   len     = (m+1)*sizeof(int)+(a->i[m])*(sizeof(Scalar)+sizeof(int));
2313   c->a  = (Scalar *) PetscMalloc( len ); CHKPTRQ(c->a);
2314   c->j  = (int *) (c->a + a->i[m] + shift);
2315   c->i  = c->j + a->i[m] + shift;
2316   PetscMemcpy(c->i,a->i,(m+1)*sizeof(int));
2317   if (m > 0) {
2318     PetscMemcpy(c->j,a->j,(a->i[m]+shift)*sizeof(int));
2319     if (cpvalues == MAT_COPY_VALUES) {
2320       PetscMemcpy(c->a,a->a,(a->i[m]+shift)*sizeof(Scalar));
2321     } else {
2322       PetscMemzero(c->a,(a->i[m]+shift)*sizeof(Scalar));
2323     }
2324   }
2325 
2326   PLogObjectMemory(C,len+2*(m+1)*sizeof(int)+sizeof(struct _p_Mat)+sizeof(Mat_SeqAIJ));
2327   c->sorted      = a->sorted;
2328   c->roworiented = a->roworiented;
2329   c->nonew       = a->nonew;
2330   c->ilu_preserve_row_sums = a->ilu_preserve_row_sums;
2331   c->saved_values = 0;
2332   c->idiag        = 0;
2333   c->ssor         = 0;
2334 
2335   if (a->diag) {
2336     c->diag = (int *) PetscMalloc( (m+1)*sizeof(int) ); CHKPTRQ(c->diag);
2337     PLogObjectMemory(C,(m+1)*sizeof(int));
2338     for ( i=0; i<m; i++ ) {
2339       c->diag[i] = a->diag[i];
2340     }
2341   } else c->diag          = 0;
2342   c->inode.limit        = a->inode.limit;
2343   c->inode.max_limit    = a->inode.max_limit;
2344   if (a->inode.size){
2345     c->inode.size       = (int *) PetscMalloc( (m+1)*sizeof(int) ); CHKPTRQ(c->inode.size);
2346     c->inode.node_count = a->inode.node_count;
2347     PetscMemcpy( c->inode.size, a->inode.size, (m+1)*sizeof(int));
2348   } else {
2349     c->inode.size       = 0;
2350     c->inode.node_count = 0;
2351   }
2352   c->nz                 = a->nz;
2353   c->maxnz              = a->maxnz;
2354   c->solve_work         = 0;
2355   c->spptr              = 0;      /* Dangerous -I'm throwing away a->spptr */
2356 
2357   *B = C;
2358   ierr = FListDuplicate(A->qlist,&C->qlist);CHKERRQ(ierr);
2359   PetscFunctionReturn(0);
2360 }
2361 
2362 #undef __FUNC__
2363 #define __FUNC__ "MatLoad_SeqAIJ"
2364 int MatLoad_SeqAIJ(Viewer viewer,MatType type,Mat *A)
2365 {
2366   Mat_SeqAIJ   *a;
2367   Mat          B;
2368   int          i, nz, ierr, fd, header[4],size,*rowlengths = 0,M,N,shift;
2369   MPI_Comm     comm;
2370 
2371   PetscFunctionBegin;
2372   ierr = PetscObjectGetComm((PetscObject) viewer,&comm);CHKERRQ(ierr);
2373   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2374   if (size > 1) SETERRQ(PETSC_ERR_ARG_SIZ,0,"view must have one processor");
2375   ierr = ViewerBinaryGetDescriptor(viewer,&fd); CHKERRQ(ierr);
2376   ierr = PetscBinaryRead(fd,header,4,PETSC_INT); CHKERRQ(ierr);
2377   if (header[0] != MAT_COOKIE) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,0,"not matrix object in file");
2378   M = header[1]; N = header[2]; nz = header[3];
2379 
2380   if (nz < 0) {
2381     SETERRQ(PETSC_ERR_FILE_UNEXPECTED,1,"Matrix stored in special format on disk, cannot load as SeqAIJ");
2382   }
2383 
2384   /* read in row lengths */
2385   rowlengths = (int*) PetscMalloc( M*sizeof(int) ); CHKPTRQ(rowlengths);
2386   ierr = PetscBinaryRead(fd,rowlengths,M,PETSC_INT); CHKERRQ(ierr);
2387 
2388   /* create our matrix */
2389   ierr = MatCreateSeqAIJ(comm,M,N,0,rowlengths,A); CHKERRQ(ierr);
2390   B = *A;
2391   a = (Mat_SeqAIJ *) B->data;
2392   shift = a->indexshift;
2393 
2394   /* read in column indices and adjust for Fortran indexing*/
2395   ierr = PetscBinaryRead(fd,a->j,nz,PETSC_INT); CHKERRQ(ierr);
2396   if (shift) {
2397     for ( i=0; i<nz; i++ ) {
2398       a->j[i] += 1;
2399     }
2400   }
2401 
2402   /* read in nonzero values */
2403   ierr = PetscBinaryRead(fd,a->a,nz,PETSC_SCALAR); CHKERRQ(ierr);
2404 
2405   /* set matrix "i" values */
2406   a->i[0] = -shift;
2407   for ( i=1; i<= M; i++ ) {
2408     a->i[i]      = a->i[i-1] + rowlengths[i-1];
2409     a->ilen[i-1] = rowlengths[i-1];
2410   }
2411   PetscFree(rowlengths);
2412 
2413   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
2414   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY); CHKERRQ(ierr);
2415   PetscFunctionReturn(0);
2416 }
2417 
2418 #undef __FUNC__
2419 #define __FUNC__ "MatEqual_SeqAIJ"
2420 int MatEqual_SeqAIJ(Mat A,Mat B, PetscTruth* flg)
2421 {
2422   Mat_SeqAIJ *a = (Mat_SeqAIJ *)A->data, *b = (Mat_SeqAIJ *)B->data;
2423 
2424   PetscFunctionBegin;
2425   if (B->type !=MATSEQAIJ)SETERRQ(PETSC_ERR_ARG_INCOMP,0,"Matrices must be same type");
2426 
2427   /* If the  matrix dimensions are not equal, or no of nonzeros or shift */
2428   if ((a->m != b->m ) || (a->n !=b->n) ||( a->nz != b->nz)||
2429       (a->indexshift != b->indexshift)) {
2430     *flg = PETSC_FALSE; PetscFunctionReturn(0);
2431   }
2432 
2433   /* if the a->i are the same */
2434   if (PetscMemcmp(a->i,b->i,(a->m+1)*sizeof(int))) {
2435     *flg = PETSC_FALSE; PetscFunctionReturn(0);
2436   }
2437 
2438   /* if a->j are the same */
2439   if (PetscMemcmp(a->j, b->j, (a->nz)*sizeof(int))) {
2440     *flg = PETSC_FALSE; PetscFunctionReturn(0);
2441   }
2442 
2443   /* if a->a are the same */
2444   if (PetscMemcmp(a->a, b->a, (a->nz)*sizeof(Scalar))) {
2445     *flg = PETSC_FALSE; PetscFunctionReturn(0);
2446   }
2447   *flg = PETSC_TRUE;
2448   PetscFunctionReturn(0);
2449 
2450 }
2451