xref: /petsc/src/mat/impls/baij/seq/baijfact.c (revision 0bbee1111da17c17490e1dbef69beeec19afa96b)
1 #ifndef lint
2 static char vcid[] = "$Id: baijfact.c,v 1.37 1997/01/10 23:54:46 balay Exp balay $";
3 #endif
4 /*
5     Factorization code for BAIJ format.
6 */
7 
8 #include "src/mat/impls/baij/seq/baij.h"
9 #include "src/vec/vecimpl.h"
10 #include "src/inline/ilu.h"
11 
12 
13 /*
14     The symbolic factorization code is identical to that for AIJ format,
15   except for very small changes since this is now a SeqBAIJ datastructure.
16   NOT good code reuse.
17 */
18 #undef __FUNC__
19 #define __FUNC__ "MatLUFactorSymbolic_SeqBAIJ"
20 int MatLUFactorSymbolic_SeqBAIJ(Mat A,IS isrow,IS iscol,double f,Mat *B)
21 {
22   Mat_SeqBAIJ *a = (Mat_SeqBAIJ *) A->data, *b;
23   IS          isicol;
24   int         *r,*ic, ierr, i, n = a->mbs, *ai = a->i, *aj = a->j;
25   int         *ainew,*ajnew, jmax,*fill, *ajtmp, nz, bs = a->bs, bs2=a->bs2;
26   int         *idnew, idx, row,m,fm, nnz, nzi,realloc = 0,nzbd,*im;
27 
28   PetscValidHeaderSpecific(isrow,IS_COOKIE);
29   PetscValidHeaderSpecific(iscol,IS_COOKIE);
30   ierr = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
31   ISGetIndices(isrow,&r); ISGetIndices(isicol,&ic);
32 
33   /* get new row pointers */
34   ainew = (int *) PetscMalloc( (n+1)*sizeof(int) ); CHKPTRQ(ainew);
35   ainew[0] = 0;
36   /* don't know how many column pointers are needed so estimate */
37   jmax = (int) (f*ai[n] + 1);
38   ajnew = (int *) PetscMalloc( (jmax)*sizeof(int) ); CHKPTRQ(ajnew);
39   /* fill is a linked list of nonzeros in active row */
40   fill = (int *) PetscMalloc( (2*n+1)*sizeof(int)); CHKPTRQ(fill);
41   im = fill + n + 1;
42   /* idnew is location of diagonal in factor */
43   idnew = (int *) PetscMalloc( (n+1)*sizeof(int)); CHKPTRQ(idnew);
44   idnew[0] = 0;
45 
46   for ( i=0; i<n; i++ ) {
47     /* first copy previous fill into linked list */
48     nnz     = nz    = ai[r[i]+1] - ai[r[i]];
49     if (!nz) SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,1,"Empty row in matrix");
50     ajtmp   = aj + ai[r[i]];
51     fill[n] = n;
52     while (nz--) {
53       fm  = n;
54       idx = ic[*ajtmp++];
55       do {
56         m  = fm;
57         fm = fill[m];
58       } while (fm < idx);
59       fill[m]   = idx;
60       fill[idx] = fm;
61     }
62     row = fill[n];
63     while ( row < i ) {
64       ajtmp = ajnew + idnew[row] + 1;
65       nzbd  = 1 + idnew[row] - ainew[row];
66       nz    = im[row] - nzbd;
67       fm    = row;
68       while (nz-- > 0) {
69         idx = *ajtmp++;
70         nzbd++;
71         if (idx == i) im[row] = nzbd;
72         do {
73           m  = fm;
74           fm = fill[m];
75         } while (fm < idx);
76         if (fm != idx) {
77           fill[m]   = idx;
78           fill[idx] = fm;
79           fm        = idx;
80           nnz++;
81         }
82       }
83       row = fill[row];
84     }
85     /* copy new filled row into permanent storage */
86     ainew[i+1] = ainew[i] + nnz;
87     if (ainew[i+1] > jmax) {
88       /* allocate a longer ajnew */
89       int maxadd;
90       maxadd = (int) ((f*(ai[n]+1)*(n-i+5))/n);
91       if (maxadd < nnz) maxadd = (n-i)*(nnz+1);
92       jmax += maxadd;
93       ajtmp = (int *) PetscMalloc( jmax*sizeof(int) );CHKPTRQ(ajtmp);
94       PetscMemcpy(ajtmp,ajnew,ainew[i]*sizeof(int));
95       PetscFree(ajnew);
96       ajnew = ajtmp;
97       realloc++; /* count how many times we realloc */
98     }
99     ajtmp = ajnew + ainew[i];
100     fm    = fill[n];
101     nzi   = 0;
102     im[i] = nnz;
103     while (nnz--) {
104       if (fm < i) nzi++;
105       *ajtmp++ = fm;
106       fm       = fill[fm];
107     }
108     idnew[i] = ainew[i] + nzi;
109   }
110 
111   PLogInfo(A,
112     "Info:MatLUFactorSymbolic_SeqBAIJ:Reallocs %d Fill ratio:given %g needed %g\n",
113                              realloc,f,((double)ainew[n])/((double)ai[i]));
114 
115   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
116   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
117 
118   PetscFree(fill);
119 
120   /* put together the new matrix */
121   ierr = MatCreateSeqBAIJ(A->comm,bs,bs*n,bs*n,0,PETSC_NULL,B); CHKERRQ(ierr);
122   PLogObjectParent(*B,isicol);
123   ierr = ISDestroy(isicol); CHKERRQ(ierr);
124   b = (Mat_SeqBAIJ *) (*B)->data;
125   PetscFree(b->imax);
126   b->singlemalloc = 0;
127   /* the next line frees the default space generated by the Create() */
128   PetscFree(b->a); PetscFree(b->ilen);
129   b->a          = (Scalar *) PetscMalloc((ainew[n]+1)*sizeof(Scalar)*bs2);CHKPTRQ(b->a);
130   b->j          = ajnew;
131   b->i          = ainew;
132   b->diag       = idnew;
133   b->ilen       = 0;
134   b->imax       = 0;
135   b->row        = isrow;
136   b->col        = iscol;
137   b->solve_work = (Scalar *) PetscMalloc( (bs*n+bs)*sizeof(Scalar));
138   CHKPTRQ(b->solve_work);
139   /* In b structure:  Free imax, ilen, old a, old j.
140      Allocate idnew, solve_work, new a, new j */
141   PLogObjectMemory(*B,(ainew[n]-n)*(sizeof(int)+sizeof(Scalar)));
142   b->maxnz = b->nz = ainew[n];
143 
144   (*B)->info.factor_mallocs    = realloc;
145   (*B)->info.fill_ratio_given  = f;
146   (*B)->info.fill_ratio_needed = ((double)ainew[n])/((double)ai[i]);
147 
148   return 0;
149 }
150 
151 /* ----------------------------------------------------------- */
152 #undef __FUNC__
153 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_N"
154 int MatLUFactorNumeric_SeqBAIJ_N(Mat A,Mat *B)
155 {
156   Mat             C = *B;
157   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
158   IS              iscol = b->col, isrow = b->row, isicol;
159   int             *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
160   int             *ajtmpold, *ajtmp, nz, row, bslog,*ai=a->i,*aj=a->j;
161   int             *diag_offset=b->diag,diag,bs=a->bs,bs2 = bs*bs,*v_pivots;
162   Scalar          *ba = b->a,*aa = a->a;
163   register Scalar *pv,*v,*rtmp,*multiplier,*v_work,*pc,*w;
164   register int    *pj;
165 
166   ierr  = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
167   PLogObjectParent(*B,isicol);
168   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
169   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
170   rtmp  = (Scalar *) PetscMalloc(bs2*(n+1)*sizeof(Scalar));CHKPTRQ(rtmp);
171   PetscMemzero(rtmp,bs2*(n+1)*sizeof(Scalar));
172   /* generate work space needed by dense LU factorization */
173   v_work     = (Scalar *) PetscMalloc(bs*sizeof(int) + (bs+bs2)*sizeof(Scalar));
174                CHKPTRQ(v_work);
175   multiplier = v_work + bs;
176   v_pivots   = (int *) (multiplier + bs2);
177 
178   /* flops in while loop */
179   bslog = 2*bs*bs2;
180 
181   for ( i=0; i<n; i++ ) {
182     nz    = bi[i+1] - bi[i];
183     ajtmp = bj + bi[i];
184     for  ( j=0; j<nz; j++ ) {
185       PetscMemzero(rtmp+bs2*ajtmp[j],bs2*sizeof(Scalar));
186     }
187     /* load in initial (unfactored row) */
188     nz       = ai[r[i]+1] - ai[r[i]];
189     ajtmpold = aj + ai[r[i]];
190     v        = aa + bs2*ai[r[i]];
191     for ( j=0; j<nz; j++ ) {
192       PetscMemcpy(rtmp+bs2*ic[ajtmpold[j]],v+bs2*j,bs2*sizeof(Scalar));
193     }
194     row = *ajtmp++;
195     while (row < i) {
196       pc = rtmp + bs2*row;
197 /*      if (*pc) { */
198         pv = ba + bs2*diag_offset[row];
199         pj = bj + diag_offset[row] + 1;
200         Kernel_A_gets_A_times_B(bs,pc,pv,multiplier);
201         nz = bi[row+1] - diag_offset[row] - 1;
202         pv += bs2;
203         for (j=0; j<nz; j++) {
204           Kernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j);
205         }
206         PLogFlops(bslog*(nz+1)-bs);
207 /*      } */
208         row = *ajtmp++;
209     }
210     /* finished row so stick it into b->a */
211     pv = ba + bs2*bi[i];
212     pj = bj + bi[i];
213     nz = bi[i+1] - bi[i];
214     for ( j=0; j<nz; j++ ) {
215       PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(Scalar));
216     }
217     diag = diag_offset[i] - bi[i];
218     /* invert diagonal block */
219     w = pv + bs2*diag;
220     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
221   }
222 
223   PetscFree(rtmp); PetscFree(v_work);
224   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
225   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
226   ierr = ISDestroy(isicol); CHKERRQ(ierr);
227   C->factor = FACTOR_LU;
228   C->assembled = PETSC_TRUE;
229   PLogFlops(1.3333*bs*bs2*b->mbs); /* from inverting diagonal blocks */
230   return 0;
231 }
232 /* ------------------------------------------------------------*/
233 /*
234       Version for when blocks are 5 by 5
235 */
236 #undef __FUNC__
237 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5"
238 int MatLUFactorNumeric_SeqBAIJ_5(Mat A,Mat *B)
239 {
240   Mat             C = *B;
241   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
242   IS              iscol = b->col, isrow = b->row, isicol;
243   int             *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
244   int             *ajtmpold, *ajtmp, nz, row, v_pivots[5];
245   int             *diag_offset = b->diag,bs = 5,idx,*ai=a->i,*aj=a->j;
246   register Scalar *pv,*v,*rtmp,*pc,*w,*x;
247   Scalar          p1,p2,p3,p4,v_work[5],m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
248   Scalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
249   Scalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
250   Scalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
251   Scalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
252   Scalar          *ba = b->a,*aa = a->a;
253   register int    *pj;
254 
255   ierr  = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
256   PLogObjectParent(*B,isicol);
257   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
258   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
259   rtmp  = (Scalar *) PetscMalloc(25*(n+1)*sizeof(Scalar));CHKPTRQ(rtmp);
260 
261   for ( i=0; i<n; i++ ) {
262     nz    = bi[i+1] - bi[i];
263     ajtmp = bj + bi[i];
264     for  ( j=0; j<nz; j++ ) {
265       x = rtmp+25*ajtmp[j];
266       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
267       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
268       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
269     }
270     /* load in initial (unfactored row) */
271     idx      = r[i];
272     nz       = ai[idx+1] - ai[idx];
273     ajtmpold = aj + ai[idx];
274     v        = aa + 25*ai[idx];
275     for ( j=0; j<nz; j++ ) {
276       x    = rtmp+25*ic[ajtmpold[j]];
277       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
278       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
279       x[9] = v[9]; x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
280       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17];
281       x[18] = v[18]; x[19] = v[19]; x[20] = v[20]; x[21] = v[21];
282       x[22] = v[22]; x[23] = v[23]; x[24] = v[24];
283       v    += 25;
284     }
285     row = *ajtmp++;
286     while (row < i) {
287       pc = rtmp + 25*row;
288       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
289       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
290       p10 = pc[9]; p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
291       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17]; p19 = pc[18];
292       p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
293       p25 = pc[24];
294       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
295           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
296           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
297           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 ||
298           p20 != 0.0 || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 ||
299           p24 != 0.0 || p25 != 0.0) {
300         pv = ba + 25*diag_offset[row];
301         pj = bj + diag_offset[row] + 1;
302         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
303         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
304         x10 = pv[9]; x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
305         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
306         x19 = pv[18]; x20 = pv[19]; x21 = pv[20]; x22 = pv[21];
307         x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
308         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
309         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
310         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
311         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
312         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
313 
314         pc[5] = m6 = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
315         pc[6] = m7 = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
316         pc[7] = m8 = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
317         pc[8] = m9 = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
318         pc[9] = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
319 
320         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
321         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
322         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
323         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
324         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
325 
326         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
327         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
328         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
329         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
330         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
331 
332         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
333         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
334         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
335         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
336         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
337 
338         nz = bi[row+1] - diag_offset[row] - 1;
339         pv += 25;
340         for (j=0; j<nz; j++) {
341           x1   = pv[0];  x2 = pv[1];   x3  = pv[2];  x4  = pv[3];
342           x5   = pv[4];  x6 = pv[5];   x7  = pv[6];  x8  = pv[7]; x9 = pv[8];
343           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
344           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16];
345           x18  = pv[17]; x19 = pv[18]; x20 = pv[19]; x21 = pv[20];
346           x22  = pv[21]; x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
347           x    = rtmp + 25*pj[j];
348           x[0] -= m1*x1 + m6*x2  + m11*x3 + m16*x4 + m21*x5;
349           x[1] -= m2*x1 + m7*x2  + m12*x3 + m17*x4 + m22*x5;
350           x[2] -= m3*x1 + m8*x2  + m13*x3 + m18*x4 + m23*x5;
351           x[3] -= m4*x1 + m9*x2  + m14*x3 + m19*x4 + m24*x5;
352           x[4] -= m5*x1 + m10*x2 + m15*x3 + m20*x4 + m25*x5;
353 
354           x[5] -= m1*x6 + m6*x7  + m11*x8 + m16*x9 + m21*x10;
355           x[6] -= m2*x6 + m7*x7  + m12*x8 + m17*x9 + m22*x10;
356           x[7] -= m3*x6 + m8*x7  + m13*x8 + m18*x9 + m23*x10;
357           x[8] -= m4*x6 + m9*x7  + m14*x8 + m19*x9 + m24*x10;
358           x[9] -= m5*x6 + m10*x7 + m15*x8 + m20*x9 + m25*x10;
359 
360           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
361           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
362           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
363           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
364           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
365 
366           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
367           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
368           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
369           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
370           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
371 
372           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
373           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
374           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
375           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
376           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
377 
378           pv   += 25;
379         }
380         PLogFlops(250*nz+225);
381       }
382       row = *ajtmp++;
383     }
384     /* finished row so stick it into b->a */
385     pv = ba + 25*bi[i];
386     pj = bj + bi[i];
387     nz = bi[i+1] - bi[i];
388     for ( j=0; j<nz; j++ ) {
389       x     = rtmp+25*pj[j];
390       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
391       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
392       pv[9] = x[9]; pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
393       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16];
394       pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20];
395       pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23]; pv[24] = x[24];
396       pv   += 25;
397     }
398     /* invert diagonal block */
399     w = ba + 25*diag_offset[i];
400     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
401   }
402 
403   PetscFree(rtmp);
404   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
405   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
406   ierr = ISDestroy(isicol); CHKERRQ(ierr);
407   C->factor = FACTOR_LU;
408   C->assembled = PETSC_TRUE;
409   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
410   return 0;
411 }
412 
413 /* ------------------------------------------------------------*/
414 /*
415       Version for when blocks are 4 by 4
416 */
417 #undef __FUNC__
418 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4"
419 int MatLUFactorNumeric_SeqBAIJ_4(Mat A,Mat *B)
420 {
421   Mat             C = *B;
422   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
423   IS              iscol = b->col, isrow = b->row, isicol;
424   int             *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
425   int             *ajtmpold, *ajtmp, nz, row, v_pivots[4];
426   int             *diag_offset = b->diag,bs = 4,idx,*ai=a->i,*aj=a->j;
427   register Scalar *pv,*v,*rtmp,*pc,*w,*x;
428   Scalar          p1,p2,p3,p4,v_work[4],m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
429   Scalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
430   Scalar          p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
431   Scalar          m13,m14,m15,m16;
432   Scalar          *ba = b->a,*aa = a->a;
433   register int    *pj;
434 
435   ierr  = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
436   PLogObjectParent(*B,isicol);
437   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
438   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
439   rtmp  = (Scalar *) PetscMalloc(16*(n+1)*sizeof(Scalar));CHKPTRQ(rtmp);
440 
441   for ( i=0; i<n; i++ ) {
442     nz    = bi[i+1] - bi[i];
443     ajtmp = bj + bi[i];
444     for  ( j=0; j<nz; j++ ) {
445       x = rtmp+16*ajtmp[j];
446       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
447       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
448     }
449     /* load in initial (unfactored row) */
450     idx      = r[i];
451     nz       = ai[idx+1] - ai[idx];
452     ajtmpold = aj + ai[idx];
453     v        = aa + 16*ai[idx];
454     for ( j=0; j<nz; j++ ) {
455       x    = rtmp+16*ic[ajtmpold[j]];
456       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
457       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
458       x[9] = v[9]; x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
459       x[14] = v[14]; x[15] = v[15];
460       v    += 16;
461     }
462     row = *ajtmp++;
463     while (row < i) {
464       pc = rtmp + 16*row;
465       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
466       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
467       p10 = pc[9]; p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
468       p15 = pc[14]; p16 = pc[15];
469       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
470           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
471           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
472           || p16 != 0.0) {
473         pv = ba + 16*diag_offset[row];
474         pj = bj + diag_offset[row] + 1;
475         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
476         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
477         x10 = pv[9]; x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
478         x15 = pv[14]; x16 = pv[15];
479         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
480         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
481         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
482         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
483 
484         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
485         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
486         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
487         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
488 
489         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
490         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
491         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
492         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
493 
494         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
495         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
496         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
497         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
498 
499         nz = bi[row+1] - diag_offset[row] - 1;
500         pv += 16;
501         for (j=0; j<nz; j++) {
502           x1   = pv[0];  x2 = pv[1];   x3  = pv[2];  x4  = pv[3];
503           x5   = pv[4];  x6 = pv[5];   x7  = pv[6];  x8  = pv[7]; x9 = pv[8];
504           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
505           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
506           x    = rtmp + 16*pj[j];
507           x[0] -= m1*x1 + m5*x2  + m9*x3 + m13*x4;
508           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
509           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
510           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
511 
512           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
513           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
514           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
515           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
516 
517           x[8] -= m1*x9  + m5*x10  + m9*x11 + m13*x12;
518           x[9] -= m2*x9  + m6*x10  + m10*x11 + m14*x12;
519           x[10] -= m3*x9 + m7*x10  + m11*x11 + m15*x12;
520           x[11] -= m4*x9 + m8*x10  + m12*x11 + m16*x12;
521 
522           x[12] -= m1*x13 + m5*x14  + m9*x15 + m13*x16;
523           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
524           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
525           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
526 
527           pv   += 16;
528         }
529         PLogFlops(128*nz+112);
530       }
531       row = *ajtmp++;
532     }
533     /* finished row so stick it into b->a */
534     pv = ba + 16*bi[i];
535     pj = bj + bi[i];
536     nz = bi[i+1] - bi[i];
537     for ( j=0; j<nz; j++ ) {
538       x     = rtmp+16*pj[j];
539       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
540       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
541       pv[9] = x[9]; pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
542       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
543       pv   += 16;
544     }
545     /* invert diagonal block */
546     w = ba + 16*diag_offset[i];
547     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
548   }
549 
550   PetscFree(rtmp);
551   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
552   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
553   ierr = ISDestroy(isicol); CHKERRQ(ierr);
554   C->factor = FACTOR_LU;
555   C->assembled = PETSC_TRUE;
556   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
557   return 0;
558 }
559 /* ------------------------------------------------------------*/
560 /*
561       Version for when blocks are 3 by 3
562 */
563 #undef __FUNC__
564 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3"
565 int MatLUFactorNumeric_SeqBAIJ_3(Mat A,Mat *B)
566 {
567   Mat             C = *B;
568   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
569   IS              iscol = b->col, isrow = b->row, isicol;
570   int             *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
571   int             *ajtmpold, *ajtmp, nz, row, *ai=a->i,*aj=a->j;
572   int             *diag_offset = b->diag,idx;
573   register Scalar *pv,*v,*rtmp,*pc,*w,*x;
574   Scalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
575   Scalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
576   Scalar          *ba = b->a,*aa = a->a;
577   register int    *pj;
578 
579   ierr  = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
580   PLogObjectParent(*B,isicol);
581   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
582   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
583   rtmp  = (Scalar *) PetscMalloc(9*(n+1)*sizeof(Scalar));CHKPTRQ(rtmp);
584 
585   for ( i=0; i<n; i++ ) {
586     nz    = bi[i+1] - bi[i];
587     ajtmp = bj + bi[i];
588     for  ( j=0; j<nz; j++ ) {
589       x = rtmp + 9*ajtmp[j];
590       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
591     }
592     /* load in initial (unfactored row) */
593     idx      = r[i];
594     nz       = ai[idx+1] - ai[idx];
595     ajtmpold = aj + ai[idx];
596     v        = aa + 9*ai[idx];
597     for ( j=0; j<nz; j++ ) {
598       x    = rtmp + 9*ic[ajtmpold[j]];
599       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
600       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
601       v    += 9;
602     }
603     row = *ajtmp++;
604     while (row < i) {
605       pc = rtmp + 9*row;
606       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
607       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
608       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
609           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
610         pv = ba + 9*diag_offset[row];
611         pj = bj + diag_offset[row] + 1;
612         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
613         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
614         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
615         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
616         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
617 
618         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
619         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
620         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
621 
622         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
623         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
624         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
625         nz = bi[row+1] - diag_offset[row] - 1;
626         pv += 9;
627         for (j=0; j<nz; j++) {
628           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
629           x5   = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
630           x    = rtmp + 9*pj[j];
631           x[0] -= m1*x1 + m4*x2 + m7*x3;
632           x[1] -= m2*x1 + m5*x2 + m8*x3;
633           x[2] -= m3*x1 + m6*x2 + m9*x3;
634 
635           x[3] -= m1*x4 + m4*x5 + m7*x6;
636           x[4] -= m2*x4 + m5*x5 + m8*x6;
637           x[5] -= m3*x4 + m6*x5 + m9*x6;
638 
639           x[6] -= m1*x7 + m4*x8 + m7*x9;
640           x[7] -= m2*x7 + m5*x8 + m8*x9;
641           x[8] -= m3*x7 + m6*x8 + m9*x9;
642           pv   += 9;
643         }
644         PLogFlops(54*nz+36);
645       }
646       row = *ajtmp++;
647     }
648     /* finished row so stick it into b->a */
649     pv = ba + 9*bi[i];
650     pj = bj + bi[i];
651     nz = bi[i+1] - bi[i];
652     for ( j=0; j<nz; j++ ) {
653       x     = rtmp + 9*pj[j];
654       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
655       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
656       pv   += 9;
657     }
658     /* invert diagonal block */
659     w = ba + 9*diag_offset[i];
660     ierr = Kernel_A_gets_inverse_A_3(w); CHKERRQ(ierr);
661   }
662 
663   PetscFree(rtmp);
664   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
665   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
666   ierr = ISDestroy(isicol); CHKERRQ(ierr);
667   C->factor = FACTOR_LU;
668   C->assembled = PETSC_TRUE;
669   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
670   return 0;
671 }
672 
673 /* ------------------------------------------------------------*/
674 /*
675       Version for when blocks are 2 by 2
676 */
677 #undef __FUNC__
678 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2"
679 int MatLUFactorNumeric_SeqBAIJ_2(Mat A,Mat *B)
680 {
681   Mat             C = *B;
682   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
683   IS              iscol = b->col, isrow = b->row, isicol;
684   int             *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
685   int             *ajtmpold, *ajtmp, nz, row, v_pivots[2];
686   int             *diag_offset=b->diag,bs = 2,idx,*ai=a->i,*aj=a->j;
687   register Scalar *pv,*v,*rtmp,m1,m2,m3,m4,*pc,*w,*x,x1,x2,x3,x4;
688   Scalar          p1,p2,p3,p4,v_work[2];
689   Scalar          *ba = b->a,*aa = a->a;
690   register int    *pj;
691 
692   ierr  = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
693   PLogObjectParent(*B,isicol);
694   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
695   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
696   rtmp  = (Scalar *) PetscMalloc(4*(n+1)*sizeof(Scalar));CHKPTRQ(rtmp);
697 
698   for ( i=0; i<n; i++ ) {
699     nz    = bi[i+1] - bi[i];
700     ajtmp = bj + bi[i];
701     for  ( j=0; j<nz; j++ ) {
702       x = rtmp+4*ajtmp[j]; x[0] = x[1] = x[2] = x[3] = 0.0;
703     }
704     /* load in initial (unfactored row) */
705     idx      = r[i];
706     nz       = ai[idx+1] - ai[idx];
707     ajtmpold = aj + ai[idx];
708     v        = aa + 4*ai[idx];
709     for ( j=0; j<nz; j++ ) {
710       x    = rtmp+4*ic[ajtmpold[j]];
711       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
712       v    += 4;
713     }
714     row = *ajtmp++;
715     while (row < i) {
716       pc = rtmp + 4*row;
717       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
718       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
719         pv = ba + 4*diag_offset[row];
720         pj = bj + diag_offset[row] + 1;
721         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
722         pc[0] = m1 = p1*x1 + p3*x2;
723         pc[1] = m2 = p2*x1 + p4*x2;
724         pc[2] = m3 = p1*x3 + p3*x4;
725         pc[3] = m4 = p2*x3 + p4*x4;
726         nz = bi[row+1] - diag_offset[row] - 1;
727         pv += 4;
728         for (j=0; j<nz; j++) {
729           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
730           x    = rtmp + 4*pj[j];
731           x[0] -= m1*x1 + m3*x2;
732           x[1] -= m2*x1 + m4*x2;
733           x[2] -= m1*x3 + m3*x4;
734           x[3] -= m2*x3 + m4*x4;
735           pv   += 4;
736         }
737         PLogFlops(16*nz+12);
738       }
739       row = *ajtmp++;
740     }
741     /* finished row so stick it into b->a */
742     pv = ba + 4*bi[i];
743     pj = bj + bi[i];
744     nz = bi[i+1] - bi[i];
745     for ( j=0; j<nz; j++ ) {
746       x     = rtmp+4*pj[j];
747       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
748       pv   += 4;
749     }
750     /* invert diagonal block */
751     w = ba + 4*diag_offset[i];
752     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
753   }
754 
755   PetscFree(rtmp);
756   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
757   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
758   ierr = ISDestroy(isicol); CHKERRQ(ierr);
759   C->factor = FACTOR_LU;
760   C->assembled = PETSC_TRUE;
761   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
762   return 0;
763 }
764 
765 /* ----------------------------------------------------------- */
766 /*
767      Version for when blocks are 1 by 1.
768 */
769 #undef __FUNC__
770 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_1"
771 int MatLUFactorNumeric_SeqBAIJ_1(Mat A,Mat *B)
772 {
773   Mat             C = *B;
774   Mat_SeqBAIJ     *a = (Mat_SeqBAIJ *) A->data, *b = (Mat_SeqBAIJ *)C->data;
775   IS              iscol = b->col, isrow = b->row, isicol;
776   int             *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
777   int             *ajtmpold, *ajtmp, nz, row,*ai = a->i,*aj = a->j;
778   int             *diag_offset = b->diag,diag;
779   register Scalar *pv,*v,*rtmp,multiplier,*pc;
780   Scalar          *ba = b->a,*aa = a->a;
781   register int    *pj;
782 
783   ierr  = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
784   PLogObjectParent(*B,isicol);
785   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
786   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
787   rtmp  = (Scalar *) PetscMalloc((n+1)*sizeof(Scalar));CHKPTRQ(rtmp);
788 
789   for ( i=0; i<n; i++ ) {
790     nz    = bi[i+1] - bi[i];
791     ajtmp = bj + bi[i];
792     for  ( j=0; j<nz; j++ ) rtmp[ajtmp[j]] = 0.0;
793 
794     /* load in initial (unfactored row) */
795     nz       = ai[r[i]+1] - ai[r[i]];
796     ajtmpold = aj + ai[r[i]];
797     v        = aa + ai[r[i]];
798     for ( j=0; j<nz; j++ ) rtmp[ic[ajtmpold[j]]] =  v[j];
799 
800     row = *ajtmp++;
801     while (row < i) {
802       pc = rtmp + row;
803       if (*pc != 0.0) {
804         pv         = ba + diag_offset[row];
805         pj         = bj + diag_offset[row] + 1;
806         multiplier = *pc * *pv++;
807         *pc        = multiplier;
808         nz         = bi[row+1] - diag_offset[row] - 1;
809         for (j=0; j<nz; j++) rtmp[pj[j]] -= multiplier * pv[j];
810         PLogFlops(1+2*nz);
811       }
812       row = *ajtmp++;
813     }
814     /* finished row so stick it into b->a */
815     pv = ba + bi[i];
816     pj = bj + bi[i];
817     nz = bi[i+1] - bi[i];
818     for ( j=0; j<nz; j++ ) {pv[j] = rtmp[pj[j]];}
819     diag = diag_offset[i] - bi[i];
820     /* check pivot entry for current row */
821     if (pv[diag] == 0.0) {
822       SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,0,"Zero pivot");
823     }
824     pv[diag] = 1.0/pv[diag];
825   }
826 
827   PetscFree(rtmp);
828   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
829   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
830   ierr = ISDestroy(isicol); CHKERRQ(ierr);
831   C->factor    = FACTOR_LU;
832   C->assembled = PETSC_TRUE;
833   PLogFlops(b->n);
834   return 0;
835 }
836 
837 /* ----------------------------------------------------------- */
838 #undef __FUNC__
839 #define __FUNC__ "MatLUFactor_SeqBAIJ"
840 int MatLUFactor_SeqBAIJ(Mat A,IS row,IS col,double f)
841 {
842   Mat_SeqBAIJ *mat = (Mat_SeqBAIJ *) A->data;
843   int         ierr;
844   Mat         C;
845 
846   ierr = MatLUFactorSymbolic(A,row,col,f,&C); CHKERRQ(ierr);
847   ierr = MatLUFactorNumeric(A,&C); CHKERRQ(ierr);
848 
849   /* free all the data structures from mat */
850   PetscFree(mat->a);
851   if (!mat->singlemalloc) {PetscFree(mat->i); PetscFree(mat->j);}
852   if (mat->diag) PetscFree(mat->diag);
853   if (mat->ilen) PetscFree(mat->ilen);
854   if (mat->imax) PetscFree(mat->imax);
855   if (mat->solve_work) PetscFree(mat->solve_work);
856   if (mat->mult_work) PetscFree(mat->mult_work);
857   PetscFree(mat);
858 
859   PetscMemcpy(A,C,sizeof(struct _Mat));
860   PetscHeaderDestroy(C);
861   return 0;
862 }
863 /* ----------------------------------------------------------- */
864 #undef __FUNC__
865 #define __FUNC__ "MatSolve_SeqBAIJ_N"
866 int MatSolve_SeqBAIJ_N(Mat A,Vec bb,Vec xx)
867 {
868   Mat_SeqBAIJ     *a=(Mat_SeqBAIJ *)A->data;
869   IS              iscol=a->col,isrow=a->row;
870   int             *r,*c,ierr,i,n=a->mbs,*vi,*ai=a->i,*aj=a->j;
871   int             nz,bs=a->bs,bs2=a->bs2,*rout,*cout;
872   Scalar          *aa=a->a,*sum;
873   register Scalar *x,*b,*lsum,*tmp,*v;
874 
875   VecGetArray_Fast(bb,b);
876   VecGetArray_Fast(xx,x);
877   tmp  = a->solve_work;
878 
879   ierr = ISGetIndices(isrow,&rout);CHKERRQ(ierr); r = rout;
880   ierr = ISGetIndices(iscol,&cout);CHKERRQ(ierr); c = cout + (n-1);
881 
882   /* forward solve the lower triangular */
883   PetscMemcpy(tmp,b + bs*(*r++), bs*sizeof(Scalar));
884   for ( i=1; i<n; i++ ) {
885     v   = aa + bs2*ai[i];
886     vi  = aj + ai[i];
887     nz  = a->diag[i] - ai[i];
888     sum = tmp + bs*i;
889     PetscMemcpy(sum,b+bs*(*r++),bs*sizeof(Scalar));
890     while (nz--) {
891       Kernel_v_gets_v_minus_A_times_w(bs,sum,v,tmp+bs*(*vi++));
892       v += bs2;
893     }
894   }
895   /* backward solve the upper triangular */
896   lsum = a->solve_work + a->n;
897   for ( i=n-1; i>=0; i-- ){
898     v   = aa + bs2*(a->diag[i] + 1);
899     vi  = aj + a->diag[i] + 1;
900     nz  = ai[i+1] - a->diag[i] - 1;
901     PetscMemcpy(lsum,tmp+i*bs,bs*sizeof(Scalar));
902     while (nz--) {
903       Kernel_v_gets_v_minus_A_times_w(bs,lsum,v,tmp+bs*(*vi++));
904       v += bs2;
905     }
906     Kernel_w_gets_A_times_v(bs,lsum,aa+bs2*a->diag[i],tmp+i*bs);
907     PetscMemcpy(x + bs*(*c--),tmp+i*bs,bs*sizeof(Scalar));
908   }
909 
910   ierr = ISRestoreIndices(isrow,&rout); CHKERRQ(ierr);
911   ierr = ISRestoreIndices(iscol,&cout); CHKERRQ(ierr);
912   VecRestoreArray_Fast(bb,b);
913   VecRestoreArray_Fast(xx,x);
914   PLogFlops(2*(a->bs2)*(a->nz) - a->n);
915   return 0;
916 }
917 
918 #undef __FUNC__
919 #define __FUNC__ "MatSolve_SeqBAIJ_5"
920 int MatSolve_SeqBAIJ_5(Mat A,Vec bb,Vec xx)
921 {
922   Mat_SeqBAIJ     *a=(Mat_SeqBAIJ *)A->data;
923   IS              iscol=a->col,isrow=a->row;
924   int             *r,*c,ierr,i,n=a->mbs,*vi,*ai=a->i,*aj=a->j,nz,idx,idt,idc,*rout,*cout;
925   Scalar          *aa=a->a,sum1,sum2,sum3,sum4,sum5,x1,x2,x3,x4,x5;
926   register Scalar *x,*b,*tmp,*v;
927 
928   VecGetArray_Fast(bb,b);
929   VecGetArray_Fast(xx,x);
930   tmp  = a->solve_work;
931 
932   ierr = ISGetIndices(isrow,&rout);CHKERRQ(ierr); r = rout;
933   ierr = ISGetIndices(iscol,&cout);CHKERRQ(ierr); c = cout + (n-1);
934 
935   /* forward solve the lower triangular */
936   idx    = 5*(*r++);
937   tmp[0] = b[idx];   tmp[1] = b[1+idx];
938   tmp[2] = b[2+idx]; tmp[3] = b[3+idx]; tmp[4] = b[4+idx];
939   for ( i=1; i<n; i++ ) {
940     v     = aa + 25*ai[i];
941     vi    = aj + ai[i];
942     nz    = a->diag[i] - ai[i];
943     idx   = 5*(*r++);
944     sum1  = b[idx];sum2 = b[1+idx];sum3 = b[2+idx];sum4 = b[3+idx];
945     sum5  = b[4+idx];
946     while (nz--) {
947       idx   = 5*(*vi++);
948       x1    = tmp[idx];  x2 = tmp[1+idx];x3 = tmp[2+idx];
949       x4    = tmp[3+idx];x5 = tmp[4+idx];
950       sum1 -= v[0]*x1 + v[5]*x2 + v[10]*x3 + v[15]*x4 + v[20]*x5;
951       sum2 -= v[1]*x1 + v[6]*x2 + v[11]*x3 + v[16]*x4 + v[21]*x5;
952       sum3 -= v[2]*x1 + v[7]*x2 + v[12]*x3 + v[17]*x4 + v[22]*x5;
953       sum4 -= v[3]*x1 + v[8]*x2 + v[13]*x3 + v[18]*x4 + v[23]*x5;
954       sum5 -= v[4]*x1 + v[9]*x2 + v[14]*x3 + v[19]*x4 + v[24]*x5;
955       v += 25;
956     }
957     idx = 5*i;
958     tmp[idx]   = sum1;tmp[1+idx] = sum2;
959     tmp[2+idx] = sum3;tmp[3+idx] = sum4; tmp[4+idx] = sum5;
960   }
961   /* backward solve the upper triangular */
962   for ( i=n-1; i>=0; i-- ){
963     v    = aa + 25*a->diag[i] + 25;
964     vi   = aj + a->diag[i] + 1;
965     nz   = ai[i+1] - a->diag[i] - 1;
966     idt  = 5*i;
967     sum1 = tmp[idt];  sum2 = tmp[1+idt];
968     sum3 = tmp[2+idt];sum4 = tmp[3+idt]; sum5 = tmp[4+idt];
969     while (nz--) {
970       idx   = 5*(*vi++);
971       x1    = tmp[idx];   x2 = tmp[1+idx];
972       x3    = tmp[2+idx]; x4 = tmp[3+idx]; x5 = tmp[4+idx];
973       sum1 -= v[0]*x1 + v[5]*x2 + v[10]*x3 + v[15]*x4 + v[20]*x5;
974       sum2 -= v[1]*x1 + v[6]*x2 + v[11]*x3 + v[16]*x4 + v[21]*x5;
975       sum3 -= v[2]*x1 + v[7]*x2 + v[12]*x3 + v[17]*x4 + v[22]*x5;
976       sum4 -= v[3]*x1 + v[8]*x2 + v[13]*x3 + v[18]*x4 + v[23]*x5;
977       sum5 -= v[4]*x1 + v[9]*x2 + v[14]*x3 + v[19]*x4 + v[24]*x5;
978       v += 25;
979     }
980     idc = 5*(*c--);
981     v   = aa + 25*a->diag[i];
982     x[idc]   = tmp[idt]   = v[0]*sum1+v[5]*sum2+v[10]*sum3+
983                                  v[15]*sum4+v[20]*sum5;
984     x[1+idc] = tmp[1+idt] = v[1]*sum1+v[6]*sum2+v[11]*sum3+
985                                  v[16]*sum4+v[21]*sum5;
986     x[2+idc] = tmp[2+idt] = v[2]*sum1+v[7]*sum2+v[12]*sum3+
987                                  v[17]*sum4+v[22]*sum5;
988     x[3+idc] = tmp[3+idt] = v[3]*sum1+v[8]*sum2+v[13]*sum3+
989                                  v[18]*sum4+v[23]*sum5;
990     x[4+idc] = tmp[4+idt] = v[4]*sum1+v[9]*sum2+v[14]*sum3+
991                                  v[19]*sum4+v[24]*sum5;
992   }
993 
994   ierr = ISRestoreIndices(isrow,&rout); CHKERRQ(ierr);
995   ierr = ISRestoreIndices(iscol,&cout); CHKERRQ(ierr);
996   VecRestoreArray_Fast(bb,b);
997   VecRestoreArray_Fast(xx,x);
998   PLogFlops(2*25*(a->nz) - a->n);
999   return 0;
1000 }
1001 
1002 #undef __FUNC__
1003 #define __FUNC__ "MatSolve_SeqBAIJ_4"
1004 int MatSolve_SeqBAIJ_4(Mat A,Vec bb,Vec xx)
1005 {
1006   Mat_SeqBAIJ     *a=(Mat_SeqBAIJ *)A->data;
1007   IS              iscol=a->col,isrow=a->row;
1008   int             *r,*c,ierr,i,n=a->mbs,*vi,*ai=a->i,*aj=a->j,nz,idx,idt,idc,*rout,*cout;
1009   Scalar          *aa=a->a,sum1,sum2,sum3,sum4,x1,x2,x3,x4;
1010   register Scalar *x,*b,*tmp,*v;
1011 
1012   VecGetArray_Fast(bb,b);
1013   VecGetArray_Fast(xx,x);
1014   tmp  = a->solve_work;
1015 
1016   ierr = ISGetIndices(isrow,&rout);CHKERRQ(ierr); r = rout;
1017   ierr = ISGetIndices(iscol,&cout);CHKERRQ(ierr); c = cout + (n-1);
1018 
1019   /* forward solve the lower triangular */
1020   idx    = 4*(*r++);
1021   tmp[0] = b[idx];   tmp[1] = b[1+idx];
1022   tmp[2] = b[2+idx]; tmp[3] = b[3+idx];
1023   for ( i=1; i<n; i++ ) {
1024     v     = aa + 16*ai[i];
1025     vi    = aj + ai[i];
1026     nz    = a->diag[i] - ai[i];
1027     idx   = 4*(*r++);
1028     sum1  = b[idx];sum2 = b[1+idx];sum3 = b[2+idx];sum4 = b[3+idx];
1029     while (nz--) {
1030       idx   = 4*(*vi++);
1031       x1    = tmp[idx];x2 = tmp[1+idx];x3 = tmp[2+idx];x4 = tmp[3+idx];
1032       sum1 -= v[0]*x1 + v[4]*x2 + v[8]*x3  + v[12]*x4;
1033       sum2 -= v[1]*x1 + v[5]*x2 + v[9]*x3  + v[13]*x4;
1034       sum3 -= v[2]*x1 + v[6]*x2 + v[10]*x3 + v[14]*x4;
1035       sum4 -= v[3]*x1 + v[7]*x2 + v[11]*x3 + v[15]*x4;
1036       v += 16;
1037     }
1038     idx = 4*i;
1039     tmp[idx]   = sum1;tmp[1+idx] = sum2;
1040     tmp[2+idx] = sum3;tmp[3+idx] = sum4;
1041   }
1042   /* backward solve the upper triangular */
1043   for ( i=n-1; i>=0; i-- ){
1044     v    = aa + 16*a->diag[i] + 16;
1045     vi   = aj + a->diag[i] + 1;
1046     nz   = ai[i+1] - a->diag[i] - 1;
1047     idt  = 4*i;
1048     sum1 = tmp[idt];  sum2 = tmp[1+idt];
1049     sum3 = tmp[2+idt];sum4 = tmp[3+idt];
1050     while (nz--) {
1051       idx   = 4*(*vi++);
1052       x1    = tmp[idx];   x2 = tmp[1+idx];
1053       x3    = tmp[2+idx]; x4 = tmp[3+idx];
1054       sum1 -= v[0]*x1 + v[4]*x2 + v[8]*x3   + v[12]*x4;
1055       sum2 -= v[1]*x1 + v[5]*x2 + v[9]*x3   + v[13]*x4;
1056       sum3 -= v[2]*x1 + v[6]*x2 + v[10]*x3  + v[14]*x4;
1057       sum4 -= v[3]*x1 + v[7]*x2 + v[11]*x3  + v[15]*x4;
1058       v += 16;
1059     }
1060     idc = 4*(*c--);
1061     v   = aa + 16*a->diag[i];
1062     x[idc]   = tmp[idt]   = v[0]*sum1+v[4]*sum2+v[8]*sum3+v[12]*sum4;
1063     x[1+idc] = tmp[1+idt] = v[1]*sum1+v[5]*sum2+v[9]*sum3+v[13]*sum4;
1064     x[2+idc] = tmp[2+idt] = v[2]*sum1+v[6]*sum2+v[10]*sum3+v[14]*sum4;
1065     x[3+idc] = tmp[3+idt] = v[3]*sum1+v[7]*sum2+v[11]*sum3+v[15]*sum4;
1066   }
1067 
1068   ierr = ISRestoreIndices(isrow,&rout); CHKERRQ(ierr);
1069   ierr = ISRestoreIndices(iscol,&cout); CHKERRQ(ierr);
1070   VecRestoreArray_Fast(bb,b);
1071   VecRestoreArray_Fast(xx,x);
1072   PLogFlops(2*16*(a->nz) - a->n);
1073   return 0;
1074 }
1075 
1076 
1077 #undef __FUNC__
1078 #define __FUNC__ "MatSolve_SeqBAIJ_3"
1079 int MatSolve_SeqBAIJ_3(Mat A,Vec bb,Vec xx)
1080 {
1081   Mat_SeqBAIJ     *a=(Mat_SeqBAIJ *)A->data;
1082   IS              iscol=a->col,isrow=a->row;
1083   int             *r,*c,ierr,i,n=a->mbs,*vi,*ai=a->i,*aj=a->j,nz,idx,idt,idc,*rout,*cout;
1084   Scalar          *aa=a->a,sum1,sum2,sum3,x1,x2,x3;
1085   register Scalar *x,*b,*tmp,*v;
1086 
1087   VecGetArray_Fast(bb,b);
1088   VecGetArray_Fast(xx,x);
1089   tmp  = a->solve_work;
1090 
1091   ierr = ISGetIndices(isrow,&rout);CHKERRQ(ierr); r = rout;
1092   ierr = ISGetIndices(iscol,&cout);CHKERRQ(ierr); c = cout + (n-1);
1093 
1094   /* forward solve the lower triangular */
1095   idx    = 3*(*r++);
1096   tmp[0] = b[idx]; tmp[1] = b[1+idx]; tmp[2] = b[2+idx];
1097   for ( i=1; i<n; i++ ) {
1098     v     = aa + 9*ai[i];
1099     vi    = aj + ai[i];
1100     nz    = a->diag[i] - ai[i];
1101     idx   = 3*(*r++);
1102     sum1  = b[idx]; sum2 = b[1+idx]; sum3 = b[2+idx];
1103     while (nz--) {
1104       idx   = 3*(*vi++);
1105       x1    = tmp[idx]; x2 = tmp[1+idx]; x3 = tmp[2+idx];
1106       sum1 -= v[0]*x1 + v[3]*x2 + v[6]*x3;
1107       sum2 -= v[1]*x1 + v[4]*x2 + v[7]*x3;
1108       sum3 -= v[2]*x1 + v[5]*x2 + v[8]*x3;
1109       v += 9;
1110     }
1111     idx = 3*i;
1112     tmp[idx] = sum1; tmp[1+idx] = sum2; tmp[2+idx] = sum3;
1113   }
1114   /* backward solve the upper triangular */
1115   for ( i=n-1; i>=0; i-- ){
1116     v    = aa + 9*a->diag[i] + 9;
1117     vi   = aj + a->diag[i] + 1;
1118     nz   = ai[i+1] - a->diag[i] - 1;
1119     idt  = 3*i;
1120     sum1 = tmp[idt]; sum2 = tmp[1+idt]; sum3 = tmp[2+idt];
1121     while (nz--) {
1122       idx   = 3*(*vi++);
1123       x1    = tmp[idx]; x2 = tmp[1+idx]; x3 = tmp[2+idx];
1124       sum1 -= v[0]*x1 + v[3]*x2 + v[6]*x3;
1125       sum2 -= v[1]*x1 + v[4]*x2 + v[7]*x3;
1126       sum3 -= v[2]*x1 + v[5]*x2 + v[8]*x3;
1127       v += 9;
1128     }
1129     idc = 3*(*c--);
1130     v   = aa + 9*a->diag[i];
1131     x[idc]   = tmp[idt]   = v[0]*sum1 + v[3]*sum2 + v[6]*sum3;
1132     x[1+idc] = tmp[1+idt] = v[1]*sum1 + v[4]*sum2 + v[7]*sum3;
1133     x[2+idc] = tmp[2+idt] = v[2]*sum1 + v[5]*sum2 + v[8]*sum3;
1134   }
1135   ierr = ISRestoreIndices(isrow,&rout); CHKERRQ(ierr);
1136   ierr = ISRestoreIndices(iscol,&cout); CHKERRQ(ierr);
1137   VecRestoreArray_Fast(bb,b);
1138   VecRestoreArray_Fast(xx,x);
1139   PLogFlops(2*9*(a->nz) - a->n);
1140   return 0;
1141 }
1142 
1143 #undef __FUNC__
1144 #define __FUNC__ "MatSolve_SeqBAIJ_2"
1145 int MatSolve_SeqBAIJ_2(Mat A,Vec bb,Vec xx)
1146 {
1147   Mat_SeqBAIJ     *a=(Mat_SeqBAIJ *)A->data;
1148   IS              iscol=a->col,isrow=a->row;
1149   int             *r,*c,ierr,i,n=a->mbs,*vi,*ai=a->i,*aj=a->j,nz,idx,idt,idc,*rout,*cout;
1150   Scalar          *aa=a->a,sum1,sum2,x1,x2;
1151   register Scalar *x,*b,*tmp,*v;
1152 
1153   VecGetArray_Fast(bb,b);
1154   VecGetArray_Fast(xx,x);
1155   tmp  = a->solve_work;
1156 
1157   ierr = ISGetIndices(isrow,&rout);CHKERRQ(ierr); r = rout;
1158   ierr = ISGetIndices(iscol,&cout);CHKERRQ(ierr); c = cout + (n-1);
1159 
1160   /* forward solve the lower triangular */
1161   idx    = 2*(*r++);
1162   tmp[0] = b[idx]; tmp[1] = b[1+idx];
1163   for ( i=1; i<n; i++ ) {
1164     v     = aa + 4*ai[i];
1165     vi    = aj + ai[i];
1166     nz    = a->diag[i] - ai[i];
1167     idx   = 2*(*r++);
1168     sum1  = b[idx]; sum2 = b[1+idx];
1169     while (nz--) {
1170       idx   = 2*(*vi++);
1171       x1    = tmp[idx]; x2 = tmp[1+idx];
1172       sum1 -= v[0]*x1 + v[2]*x2;
1173       sum2 -= v[1]*x1 + v[3]*x2;
1174       v += 4;
1175     }
1176     idx = 2*i;
1177     tmp[idx] = sum1; tmp[1+idx] = sum2;
1178   }
1179   /* backward solve the upper triangular */
1180   for ( i=n-1; i>=0; i-- ){
1181     v    = aa + 4*a->diag[i] + 4;
1182     vi   = aj + a->diag[i] + 1;
1183     nz   = ai[i+1] - a->diag[i] - 1;
1184     idt  = 2*i;
1185     sum1 = tmp[idt]; sum2 = tmp[1+idt];
1186     while (nz--) {
1187       idx   = 2*(*vi++);
1188       x1    = tmp[idx]; x2 = tmp[1+idx];
1189       sum1 -= v[0]*x1 + v[2]*x2;
1190       sum2 -= v[1]*x1 + v[3]*x2;
1191       v += 4;
1192     }
1193     idc = 2*(*c--);
1194     v   = aa + 4*a->diag[i];
1195     x[idc]   = tmp[idt]   = v[0]*sum1 + v[2]*sum2;
1196     x[1+idc] = tmp[1+idt] = v[1]*sum1 + v[3]*sum2;
1197   }
1198   ierr = ISRestoreIndices(isrow,&rout); CHKERRQ(ierr);
1199   ierr = ISRestoreIndices(iscol,&cout); CHKERRQ(ierr);
1200   VecRestoreArray_Fast(bb,b);
1201   VecRestoreArray_Fast(xx,x);
1202   PLogFlops(2*4*(a->nz) - a->n);
1203   return 0;
1204 }
1205 
1206 
1207 #undef __FUNC__
1208 #define __FUNC__ "MatSolve_SeqBAIJ_1"
1209 int MatSolve_SeqBAIJ_1(Mat A,Vec bb,Vec xx)
1210 {
1211   Mat_SeqBAIJ     *a=(Mat_SeqBAIJ *)A->data;
1212   IS              iscol=a->col,isrow=a->row;
1213   int             *r,*c,ierr,i,n=a->mbs,*vi,*ai=a->i,*aj=a->j,nz,*rout,*cout;
1214   Scalar          *aa=a->a,sum1;
1215   register Scalar *x,*b,*tmp,*v;
1216 
1217   if (!n) return 0;
1218 
1219   VecGetArray_Fast(bb,b);
1220   VecGetArray_Fast(xx,x);
1221   tmp  = a->solve_work;
1222 
1223   ierr = ISGetIndices(isrow,&rout);CHKERRQ(ierr); r = rout;
1224   ierr = ISGetIndices(iscol,&cout);CHKERRQ(ierr); c = cout + (n-1);
1225 
1226   /* forward solve the lower triangular */
1227   tmp[0] = b[*r++];
1228   for ( i=1; i<n; i++ ) {
1229     v     = aa + ai[i];
1230     vi    = aj + ai[i];
1231     nz    = a->diag[i] - ai[i];
1232     sum1  = b[*r++];
1233     while (nz--) {
1234       sum1 -= (*v++)*tmp[*vi++];
1235     }
1236     tmp[i] = sum1;
1237   }
1238   /* backward solve the upper triangular */
1239   for ( i=n-1; i>=0; i-- ){
1240     v    = aa + a->diag[i] + 1;
1241     vi   = aj + a->diag[i] + 1;
1242     nz   = ai[i+1] - a->diag[i] - 1;
1243     sum1 = tmp[i];
1244     while (nz--) {
1245       sum1 -= (*v++)*tmp[*vi++];
1246     }
1247     x[*c--] = tmp[i] = aa[a->diag[i]]*sum1;
1248   }
1249 
1250   ierr = ISRestoreIndices(isrow,&rout); CHKERRQ(ierr);
1251   ierr = ISRestoreIndices(iscol,&cout); CHKERRQ(ierr);
1252   VecRestoreArray_Fast(bb,b);
1253   VecRestoreArray_Fast(xx,x);
1254   PLogFlops(2*1*(a->nz) - a->n);
1255   return 0;
1256 }
1257 
1258 /* ----------------------------------------------------------------*/
1259 /*
1260      This code is virtually identical to MatILUFactorSymbolic_SeqAIJ
1261    except that the data structure of Mat_SeqAIJ is slightly different.
1262    Not a good example of code reuse.
1263 */
1264 #undef __FUNC__
1265 #define __FUNC__ "MatILUFactorSymbolic_SeqBAIJ"
1266 int MatILUFactorSymbolic_SeqBAIJ(Mat A,IS isrow,IS iscol,double f,int levels,
1267                                  Mat *fact)
1268 {
1269   Mat_SeqBAIJ *a = (Mat_SeqBAIJ *) A->data, *b;
1270   IS          isicol;
1271   int         *r,*ic, ierr, prow, n = a->mbs, *ai = a->i, *aj = a->j;
1272   int         *ainew,*ajnew, jmax,*fill, *xi, nz, *im,*ajfill,*flev;
1273   int         *dloc, idx, row,m,fm, nzf, nzi,len,  realloc = 0;
1274   int         incrlev,nnz,i,bs = a->bs,bs2 = a->bs2;
1275   PetscTruth  col_identity, row_identity;
1276 
1277   /* special case that simply copies fill pattern */
1278   PetscValidHeaderSpecific(isrow,IS_COOKIE);
1279   PetscValidHeaderSpecific(iscol,IS_COOKIE);
1280   ISIdentity(isrow,&row_identity); ISIdentity(iscol,&col_identity);
1281   if (levels == 0 && row_identity && col_identity) {
1282     ierr = MatConvertSameType_SeqBAIJ(A,fact,DO_NOT_COPY_VALUES); CHKERRQ(ierr);
1283     (*fact)->factor = FACTOR_LU;
1284     b               = (Mat_SeqBAIJ *) (*fact)->data;
1285     if (!b->diag) {
1286       ierr = MatMarkDiag_SeqBAIJ(*fact); CHKERRQ(ierr);
1287     }
1288     b->row        = isrow;
1289     b->col        = iscol;
1290     b->solve_work = (Scalar *) PetscMalloc((b->m+1+b->bs)*sizeof(Scalar));CHKPTRQ(b->solve_work);
1291     return 0;
1292   }
1293 
1294   ierr = ISInvertPermutation(iscol,&isicol); CHKERRQ(ierr);
1295   ierr = ISGetIndices(isrow,&r); CHKERRQ(ierr);
1296   ierr = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
1297 
1298   /* get new row pointers */
1299   ainew = (int *) PetscMalloc( (n+1)*sizeof(int) ); CHKPTRQ(ainew);
1300   ainew[0] = 0;
1301   /* don't know how many column pointers are needed so estimate */
1302   jmax = (int) (f*ai[n] + 1);
1303   ajnew = (int *) PetscMalloc( (jmax)*sizeof(int) ); CHKPTRQ(ajnew);
1304   /* ajfill is level of fill for each fill entry */
1305   ajfill = (int *) PetscMalloc( (jmax)*sizeof(int) ); CHKPTRQ(ajfill);
1306   /* fill is a linked list of nonzeros in active row */
1307   fill = (int *) PetscMalloc( (n+1)*sizeof(int)); CHKPTRQ(fill);
1308   /* im is level for each filled value */
1309   im = (int *) PetscMalloc( (n+1)*sizeof(int)); CHKPTRQ(im);
1310   /* dloc is location of diagonal in factor */
1311   dloc = (int *) PetscMalloc( (n+1)*sizeof(int)); CHKPTRQ(dloc);
1312   dloc[0]  = 0;
1313   for ( prow=0; prow<n; prow++ ) {
1314     /* first copy previous fill into linked list */
1315     nzf     = nz  = ai[r[prow]+1] - ai[r[prow]];
1316     if (!nz) SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,1,"Empty row in matrix");
1317     xi      = aj + ai[r[prow]];
1318     fill[n] = n;
1319     while (nz--) {
1320       fm  = n;
1321       idx = ic[*xi++];
1322       do {
1323         m  = fm;
1324         fm = fill[m];
1325       } while (fm < idx);
1326       fill[m]   = idx;
1327       fill[idx] = fm;
1328       im[idx]   = 0;
1329     }
1330     nzi = 0;
1331     row = fill[n];
1332     while ( row < prow ) {
1333       incrlev = im[row] + 1;
1334       nz      = dloc[row];
1335       xi      = ajnew  + ainew[row] + nz;
1336       flev    = ajfill + ainew[row] + nz + 1;
1337       nnz     = ainew[row+1] - ainew[row] - nz - 1;
1338       if (*xi++ != row) {
1339         SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,0,"zero pivot");
1340       }
1341       fm      = row;
1342       while (nnz-- > 0) {
1343         idx = *xi++;
1344         if (*flev + incrlev > levels) {
1345           flev++;
1346           continue;
1347         }
1348         do {
1349           m  = fm;
1350           fm = fill[m];
1351         } while (fm < idx);
1352         if (fm != idx) {
1353           im[idx]   = *flev + incrlev;
1354           fill[m]   = idx;
1355           fill[idx] = fm;
1356           fm        = idx;
1357           nzf++;
1358         }
1359         else {
1360           if (im[idx] > *flev + incrlev) im[idx] = *flev+incrlev;
1361         }
1362         flev++;
1363       }
1364       row = fill[row];
1365       nzi++;
1366     }
1367     /* copy new filled row into permanent storage */
1368     ainew[prow+1] = ainew[prow] + nzf;
1369     if (ainew[prow+1] > jmax) {
1370       /* allocate a longer ajnew */
1371       int maxadd;
1372       maxadd = (int) (((f*ai[n]+1)*(n-prow+5))/n);
1373       if (maxadd < nzf) maxadd = (n-prow)*(nzf+1);
1374       jmax += maxadd;
1375       xi = (int *) PetscMalloc( jmax*sizeof(int) );CHKPTRQ(xi);
1376       PetscMemcpy(xi,ajnew,ainew[prow]*sizeof(int));
1377       PetscFree(ajnew);
1378       ajnew = xi;
1379       /* allocate a longer ajfill */
1380       xi = (int *) PetscMalloc( jmax*sizeof(int) );CHKPTRQ(xi);
1381       PetscMemcpy(xi,ajfill,ainew[prow]*sizeof(int));
1382       PetscFree(ajfill);
1383       ajfill = xi;
1384       realloc++;
1385     }
1386     xi          = ajnew + ainew[prow];
1387     flev        = ajfill + ainew[prow];
1388     dloc[prow]  = nzi;
1389     fm          = fill[n];
1390     while (nzf--) {
1391       *xi++   = fm;
1392       *flev++ = im[fm];
1393       fm      = fill[fm];
1394     }
1395   }
1396   PetscFree(ajfill);
1397   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
1398   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
1399   ierr = ISDestroy(isicol); CHKERRQ(ierr);
1400   PetscFree(fill); PetscFree(im);
1401 
1402   PLogInfo(A,
1403     "Info:MatILUFactorSymbolic_SeqBAIJ:Realloc %d Fill ratio:given %g needed %g\n",
1404                              realloc,f,((double)ainew[n])/((double)ai[prow]));
1405 
1406   /* put together the new matrix */
1407   ierr = MatCreateSeqBAIJ(A->comm,bs,bs*n,bs*n,0,PETSC_NULL,fact);CHKERRQ(ierr);
1408   b = (Mat_SeqBAIJ *) (*fact)->data;
1409   PetscFree(b->imax);
1410   b->singlemalloc = 0;
1411   len = bs2*ainew[n]*sizeof(Scalar);
1412   /* the next line frees the default space generated by the Create() */
1413   PetscFree(b->a); PetscFree(b->ilen);
1414   b->a          = (Scalar *) PetscMalloc( len ); CHKPTRQ(b->a);
1415   b->j          = ajnew;
1416   b->i          = ainew;
1417   for ( i=0; i<n; i++ ) dloc[i] += ainew[i];
1418   b->diag       = dloc;
1419   b->ilen       = 0;
1420   b->imax       = 0;
1421   b->row        = isrow;
1422   b->col        = iscol;
1423   b->solve_work = (Scalar *) PetscMalloc( (bs*n+bs)*sizeof(Scalar));
1424   CHKPTRQ(b->solve_work);
1425   /* In b structure:  Free imax, ilen, old a, old j.
1426      Allocate dloc, solve_work, new a, new j */
1427   PLogObjectMemory(*fact,(ainew[n]-n)*(sizeof(int))+bs2*ainew[n]*sizeof(Scalar));
1428   b->maxnz          = b->nz = ainew[n];
1429   (*fact)->factor   = FACTOR_LU;
1430 
1431   (*fact)->info.factor_mallocs    = realloc;
1432   (*fact)->info.fill_ratio_given  = f;
1433   (*fact)->info.fill_ratio_needed = ((double)ainew[n])/((double)ai[prow]);
1434 
1435   return 0;
1436 }
1437 
1438 
1439 
1440 
1441