xref: /petsc/src/mat/impls/baij/seq/baijfact.c (revision a3b388050d4e8a4c38128e174a7572fa24ee1ba5)
1 #ifdef PETSC_RCS_HEADER
2 static char vcid[] = "$Id: baijfact.c,v 1.72 1999/05/04 20:32:27 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   PetscFunctionBegin;
29   PetscValidHeaderSpecific(isrow,IS_COOKIE);
30   PetscValidHeaderSpecific(iscol,IS_COOKIE);
31   ierr = ISInvertPermutation(iscol,&isicol);CHKERRQ(ierr);
32   ISGetIndices(isrow,&r); ISGetIndices(isicol,&ic);
33 
34   /* get new row pointers */
35   ainew = (int *) PetscMalloc( (n+1)*sizeof(int) );CHKPTRQ(ainew);
36   ainew[0] = 0;
37   /* don't know how many column pointers are needed so estimate */
38   jmax = (int) (f*ai[n] + 1);
39   ajnew = (int *) PetscMalloc( (jmax)*sizeof(int) );CHKPTRQ(ajnew);
40   /* fill is a linked list of nonzeros in active row */
41   fill = (int *) PetscMalloc( (2*n+1)*sizeof(int));CHKPTRQ(fill);
42   im = fill + n + 1;
43   /* idnew is location of diagonal in factor */
44   idnew = (int *) PetscMalloc( (n+1)*sizeof(int));CHKPTRQ(idnew);
45   idnew[0] = 0;
46 
47   for ( i=0; i<n; i++ ) {
48     /* first copy previous fill into linked list */
49     nnz     = nz    = ai[r[i]+1] - ai[r[i]];
50     if (!nz) SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,1,"Empty row in matrix");
51     ajtmp   = aj + ai[r[i]];
52     fill[n] = n;
53     while (nz--) {
54       fm  = n;
55       idx = ic[*ajtmp++];
56       do {
57         m  = fm;
58         fm = fill[m];
59       } while (fm < idx);
60       fill[m]   = idx;
61       fill[idx] = fm;
62     }
63     row = fill[n];
64     while ( row < i ) {
65       ajtmp = ajnew + idnew[row] + 1;
66       nzbd  = 1 + idnew[row] - ainew[row];
67       nz    = im[row] - nzbd;
68       fm    = row;
69       while (nz-- > 0) {
70         idx = *ajtmp++;
71         nzbd++;
72         if (idx == i) im[row] = nzbd;
73         do {
74           m  = fm;
75           fm = fill[m];
76         } while (fm < idx);
77         if (fm != idx) {
78           fill[m]   = idx;
79           fill[idx] = fm;
80           fm        = idx;
81           nnz++;
82         }
83       }
84       row = fill[row];
85     }
86     /* copy new filled row into permanent storage */
87     ainew[i+1] = ainew[i] + nnz;
88     if (ainew[i+1] > jmax) {
89 
90       /* estimate how much additional space we will need */
91       /* use the strategy suggested by David Hysom <hysom@perch-t.icase.edu> */
92       /* just double the memory each time */
93       int maxadd = jmax;
94       /* maxadd = (int) ((f*(ai[n]+1)*(n-i+5))/n); */
95       if (maxadd < nnz) maxadd = (n-i)*(nnz+1);
96       jmax += maxadd;
97 
98       /* allocate a longer ajnew */
99       ajtmp = (int *) PetscMalloc( jmax*sizeof(int) );CHKPTRQ(ajtmp);
100       ierr  = PetscMemcpy(ajtmp,ajnew,ainew[i]*sizeof(int));CHKERRQ(ierr);
101       ierr = PetscFree(ajnew);CHKERRQ(ierr);
102       ajnew = ajtmp;
103       realloc++; /* count how many times we realloc */
104     }
105     ajtmp = ajnew + ainew[i];
106     fm    = fill[n];
107     nzi   = 0;
108     im[i] = nnz;
109     while (nnz--) {
110       if (fm < i) nzi++;
111       *ajtmp++ = fm;
112       fm       = fill[fm];
113     }
114     idnew[i] = ainew[i] + nzi;
115   }
116 
117   if (ai[n] != 0) {
118     double af = ((double)ainew[n])/((double)ai[n]);
119     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Reallocs %d Fill ratio:given %g needed %g\n",
120              realloc,f,af);
121     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Run with -pc_lu_fill %g or use \n",af);
122     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:PCLUSetFill(pc,%g);\n",af);
123     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:for best performance.\n");
124   } else {
125      PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Empty matrix.\n");
126   }
127 
128   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
129   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
130 
131   ierr = PetscFree(fill);CHKERRQ(ierr);
132 
133   /* put together the new matrix */
134   ierr = MatCreateSeqBAIJ(A->comm,bs,bs*n,bs*n,0,PETSC_NULL,B);CHKERRQ(ierr);
135   PLogObjectParent(*B,isicol);
136   b = (Mat_SeqBAIJ *) (*B)->data;
137   ierr = PetscFree(b->imax);CHKERRQ(ierr);
138   b->singlemalloc = 0;
139   /* the next line frees the default space generated by the Create() */
140   ierr = PetscFree(b->a);CHKERRQ(ierr);
141   ierr = PetscFree(b->ilen);CHKERRQ(ierr);
142   b->a          = (MatScalar *) PetscMalloc((ainew[n]+1)*sizeof(MatScalar)*bs2);CHKPTRQ(b->a);
143   b->j          = ajnew;
144   b->i          = ainew;
145   b->diag       = idnew;
146   b->ilen       = 0;
147   b->imax       = 0;
148   b->row        = isrow;
149   b->col        = iscol;
150   b->icol       = isicol;
151   b->solve_work = (Scalar *) PetscMalloc( (bs*n+bs)*sizeof(Scalar));CHKPTRQ(b->solve_work);
152   /* In b structure:  Free imax, ilen, old a, old j.
153      Allocate idnew, solve_work, new a, new j */
154   PLogObjectMemory(*B,(ainew[n]-n)*(sizeof(int)+sizeof(MatScalar)));
155   b->maxnz = b->nz = ainew[n];
156 
157   (*B)->factor                 = FACTOR_LU;
158   (*B)->info.factor_mallocs    = realloc;
159   (*B)->info.fill_ratio_given  = f;
160   if (ai[n] != 0) {
161     (*B)->info.fill_ratio_needed = ((double)ainew[n])/((double)ai[n]);
162   } else {
163     (*B)->info.fill_ratio_needed = 0.0;
164   }
165 
166 
167   PetscFunctionReturn(0);
168 }
169 
170 /* ----------------------------------------------------------- */
171 #undef __FUNC__
172 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_N"
173 int MatLUFactorNumeric_SeqBAIJ_N(Mat A,Mat *B)
174 {
175   Mat                C = *B;
176   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
177   IS                 isrow = b->row, isicol = b->icol;
178   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
179   int                *ajtmpold, *ajtmp, nz, row, bslog,*ai=a->i,*aj=a->j,k,flg;
180   int                *diag_offset=b->diag,diag,bs=a->bs,bs2 = a->bs2,*v_pivots;
181   register int       *pj;
182   register MatScalar *pv,*v,*rtmp,*multiplier,*v_work,*pc,*w;
183   MatScalar          *ba = b->a,*aa = a->a;
184 
185   PetscFunctionBegin;
186   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
187   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
188   rtmp = (MatScalar *) PetscMalloc(bs2*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
189   ierr = PetscMemzero(rtmp,bs2*(n+1)*sizeof(MatScalar));CHKERRQ(ierr);
190   /* generate work space needed by dense LU factorization */
191   v_work     = (MatScalar *) PetscMalloc(bs*sizeof(int) + (bs+bs2)*sizeof(MatScalar));CHKPTRQ(v_work);
192   multiplier = v_work + bs;
193   v_pivots   = (int *) (multiplier + bs2);
194 
195   /* flops in while loop */
196   bslog = 2*bs*bs2;
197 
198   for ( i=0; i<n; i++ ) {
199     nz    = bi[i+1] - bi[i];
200     ajtmp = bj + bi[i];
201     for  ( j=0; j<nz; j++ ) {
202       ierr = PetscMemzero(rtmp+bs2*ajtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
203     }
204     /* load in initial (unfactored row) */
205     nz       = ai[r[i]+1] - ai[r[i]];
206     ajtmpold = aj + ai[r[i]];
207     v        = aa + bs2*ai[r[i]];
208     for ( j=0; j<nz; j++ ) {
209       ierr = PetscMemcpy(rtmp+bs2*ic[ajtmpold[j]],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
210     }
211     row = *ajtmp++;
212     while (row < i) {
213       pc = rtmp + bs2*row;
214 /*      if (*pc) { */
215       for ( flg=0,k=0; k<bs2; k++ ) { if (pc[k]!=0.0) { flg =1; break; }}
216       if (flg) {
217         pv = ba + bs2*diag_offset[row];
218         pj = bj + diag_offset[row] + 1;
219         Kernel_A_gets_A_times_B(bs,pc,pv,multiplier);
220         nz = bi[row+1] - diag_offset[row] - 1;
221         pv += bs2;
222         for (j=0; j<nz; j++) {
223           Kernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j);
224         }
225         PLogFlops(bslog*(nz+1)-bs);
226       }
227         row = *ajtmp++;
228     }
229     /* finished row so stick it into b->a */
230     pv = ba + bs2*bi[i];
231     pj = bj + bi[i];
232     nz = bi[i+1] - bi[i];
233     for ( j=0; j<nz; j++ ) {
234       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
235     }
236     diag = diag_offset[i] - bi[i];
237     /* invert diagonal block */
238     w = pv + bs2*diag;
239     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
240   }
241 
242   ierr = PetscFree(rtmp);CHKERRQ(ierr);
243   ierr = PetscFree(v_work);CHKERRQ(ierr);
244   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
245   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
246   C->factor = FACTOR_LU;
247   C->assembled = PETSC_TRUE;
248   PLogFlops(1.3333*bs*bs2*b->mbs); /* from inverting diagonal blocks */
249   PetscFunctionReturn(0);
250 }
251 /* ------------------------------------------------------------*/
252 /*
253       Version for when blocks are 7 by 7
254 */
255 #undef __FUNC__
256 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7"
257 int MatLUFactorNumeric_SeqBAIJ_7(Mat A,Mat *B)
258 {
259   Mat                C = *B;
260   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
261   IS                 isrow = b->row, isicol = b->icol;
262   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
263   int                *ajtmpold, *ajtmp, nz, row;
264   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
265   register int       *pj;
266   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
267   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
268   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
269   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
270   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
271   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
272   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
273   MatScalar          p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
274   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
275   MatScalar          x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
276   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
277   MatScalar          m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
278   MatScalar          *ba = b->a,*aa = a->a;
279 
280   PetscFunctionBegin;
281   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
282   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
283   rtmp  = (MatScalar *) PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
284 
285   for ( i=0; i<n; i++ ) {
286     nz    = bi[i+1] - bi[i];
287     ajtmp = bj + bi[i];
288     for  ( j=0; j<nz; j++ ) {
289       x = rtmp+49*ajtmp[j];
290       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
291       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
292       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
293       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
294       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
295       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
296     }
297     /* load in initial (unfactored row) */
298     idx      = r[i];
299     nz       = ai[idx+1] - ai[idx];
300     ajtmpold = aj + ai[idx];
301     v        = aa + 49*ai[idx];
302     for ( j=0; j<nz; j++ ) {
303       x    = rtmp+49*ic[ajtmpold[j]];
304       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
305       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
306       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
307       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
308       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
309       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
310       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
311       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
312       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
313       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
314       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
315       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
316       x[48] = v[48];
317       v    += 49;
318     }
319     row = *ajtmp++;
320     while (row < i) {
321       pc  =  rtmp + 49*row;
322       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
323       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
324       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
325       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
326       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
327       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
328       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
329       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
330       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
331       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
332       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
333       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
334       p49 = pc[48];
335       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
336           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
337           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
338           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
339           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
340           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
341           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
342           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
343           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
344           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
345           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
346           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
347           p49 != 0.0) {
348         pv = ba + 49*diag_offset[row];
349         pj = bj + diag_offset[row] + 1;
350 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
351 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
352 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
353 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
354 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
355 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
356 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
357 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
358 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
359 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
360 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
361 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
362 	x49 = pv[48];
363         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
364         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
365         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
366         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
367         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
368         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
369         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
370 
371         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
372         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
373         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
374         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
375         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
376         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
377         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
378 
379         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
380         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
381         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
382         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
383         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
384         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
385         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
386 
387         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
388         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
389         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
390         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
391         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
392         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
393         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
394 
395         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
396         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
397         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
398         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
399         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
400         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
401         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
402 
403         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
404         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
405         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
406         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
407         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
408         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
409         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
410 
411         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
412         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
413         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
414         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
415         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
416         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
417         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
418 
419         nz = bi[row+1] - diag_offset[row] - 1;
420         pv += 49;
421         for (j=0; j<nz; j++) {
422 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
423 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
424 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
425 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
426 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
427 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
428 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
429 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
430 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
431 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
432 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
433 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
434 	  x49 = pv[48];
435 	  x    = rtmp + 49*pj[j];
436 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
437 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
438 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
439 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
440 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
441 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
442 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
443 
444 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
445 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
446 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
447 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
448 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
449 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
450 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
451 
452 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
453 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
454 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
455 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
456 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
457 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
458 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
459 
460 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
461 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
462 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
463 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
464 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
465 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
466 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
467 
468 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
469 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
470 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
471 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
472 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
473 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
474 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
475 
476 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
477 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
478 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
479 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
480 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
481 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
482 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
483 
484 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
485 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
486 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
487 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
488 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
489 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
490 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
491           pv   += 49;
492         }
493         PLogFlops(686*nz+637);
494       }
495       row = *ajtmp++;
496     }
497     /* finished row so stick it into b->a */
498     pv = ba + 49*bi[i];
499     pj = bj + bi[i];
500     nz = bi[i+1] - bi[i];
501     for ( j=0; j<nz; j++ ) {
502       x      = rtmp+49*pj[j];
503       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
504       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
505       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
506       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
507       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
508       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
509       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
510       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
511       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
512       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
513       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
514       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
515       pv[48] = x[48];
516       pv   += 49;
517     }
518     /* invert diagonal block */
519     w = ba + 49*diag_offset[i];
520     ierr = Kernel_A_gets_inverse_A_7(w);CHKERRQ(ierr);
521   }
522 
523   ierr = PetscFree(rtmp);CHKERRQ(ierr);
524   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
525   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
526   C->factor = FACTOR_LU;
527   C->assembled = PETSC_TRUE;
528   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
529   PetscFunctionReturn(0);
530 }
531 
532 /*
533       Version for when blocks are 7 by 7 Using natural ordering
534 */
535 #undef __FUNC__
536 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering"
537 int MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering(Mat A,Mat *B)
538 {
539   Mat                C = *B;
540   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
541   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
542   int                *ajtmpold, *ajtmp, nz, row;
543   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
544   register int       *pj;
545   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
546   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
547   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
548   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
549   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
550   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
551   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
552   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
553   MatScalar          p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
554   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
555   MatScalar          x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
556   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
557   MatScalar          m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
558   MatScalar          *ba = b->a,*aa = a->a;
559 
560   PetscFunctionBegin;
561   rtmp  = (MatScalar *) PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
562   for ( i=0; i<n; i++ ) {
563     nz    = bi[i+1] - bi[i];
564     ajtmp = bj + bi[i];
565     for  ( j=0; j<nz; j++ ) {
566       x = rtmp+49*ajtmp[j];
567       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
568       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
569       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
570       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
571       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
572       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
573     }
574     /* load in initial (unfactored row) */
575     nz       = ai[i+1] - ai[i];
576     ajtmpold = aj + ai[i];
577     v        = aa + 49*ai[i];
578     for ( j=0; j<nz; j++ ) {
579       x    = rtmp+49*ajtmpold[j];
580       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
581       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
582       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
583       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
584       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
585       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
586       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
587       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
588       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
589       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
590       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
591       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
592       x[48] = v[48];
593       v    += 49;
594     }
595     row = *ajtmp++;
596     while (row < i) {
597       pc  = rtmp + 49*row;
598       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
599       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
600       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
601       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
602       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
603       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
604       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
605       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
606       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
607       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
608       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
609       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
610       p49 = pc[48];
611       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
612           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
613           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
614           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
615           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
616           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
617           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
618           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
619           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
620           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
621           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
622           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
623           p49 != 0.0) {
624         pv = ba + 49*diag_offset[row];
625         pj = bj + diag_offset[row] + 1;
626 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
627 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
628 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
629 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
630 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
631 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
632 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
633 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
634 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
635 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
636 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
637 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
638         x49 = pv[48];
639         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
640         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
641         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
642         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
643         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
644         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
645         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
646 
647         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
648         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
649         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
650         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
651         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
652         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
653         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
654 
655         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
656         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
657         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
658         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
659         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
660         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
661         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
662 
663         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
664         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
665         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
666         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
667         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
668         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
669         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
670 
671         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
672         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
673         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
674         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
675         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
676         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
677         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
678 
679         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
680         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
681         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
682         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
683         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
684         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
685         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
686 
687         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
688         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
689         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
690         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
691         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
692         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
693         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
694 
695         nz = bi[row+1] - diag_offset[row] - 1;
696         pv += 49;
697         for (j=0; j<nz; j++) {
698 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
699 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
700 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
701 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
702 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
703 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
704 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
705 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
706 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
707 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
708 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
709 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
710 	  x49 = pv[48];
711 	  x    = rtmp + 49*pj[j];
712 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
713 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
714 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
715 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
716 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
717 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
718 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
719 
720 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
721 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
722 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
723 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
724 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
725 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
726 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
727 
728 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
729 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
730 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
731 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
732 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
733 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
734 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
735 
736 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
737 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
738 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
739 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
740 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
741 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
742 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
743 
744 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
745 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
746 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
747 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
748 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
749 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
750 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
751 
752 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
753 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
754 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
755 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
756 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
757 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
758 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
759 
760 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
761 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
762 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
763 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
764 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
765 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
766 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
767           pv   += 49;
768         }
769         PLogFlops(686*nz+637);
770       }
771       row = *ajtmp++;
772     }
773     /* finished row so stick it into b->a */
774     pv = ba + 49*bi[i];
775     pj = bj + bi[i];
776     nz = bi[i+1] - bi[i];
777     for ( j=0; j<nz; j++ ) {
778       x      = rtmp+49*pj[j];
779       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
780       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
781       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
782       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
783       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
784       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
785       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
786       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
787       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
788       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
789       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
790       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
791       pv[48] = x[48];
792       pv   += 49;
793     }
794     /* invert diagonal block */
795     w = ba + 49*diag_offset[i];
796     ierr = Kernel_A_gets_inverse_A_7(w);CHKERRQ(ierr);
797   }
798 
799   ierr = PetscFree(rtmp);CHKERRQ(ierr);
800   C->factor    = FACTOR_LU;
801   C->assembled = PETSC_TRUE;
802   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
803   PetscFunctionReturn(0);
804 }
805 
806 /* ------------------------------------------------------------*/
807 /*
808       Version for when blocks are 6 by 6
809 */
810 #undef __FUNC__
811 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6"
812 int MatLUFactorNumeric_SeqBAIJ_6(Mat A,Mat *B)
813 {
814   Mat                C = *B;
815   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
816   IS                 isrow = b->row, isicol = b->icol;
817   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
818   int                *ajtmpold, *ajtmp, nz, row;
819   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
820   register int       *pj;
821   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
822   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
823   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
824   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
825   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
826   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
827   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
828   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
829   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
830   MatScalar          *ba = b->a,*aa = a->a;
831 
832   PetscFunctionBegin;
833   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
834   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
835   rtmp  = (MatScalar *) PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
836 
837   for ( i=0; i<n; i++ ) {
838     nz    = bi[i+1] - bi[i];
839     ajtmp = bj + bi[i];
840     for  ( j=0; j<nz; j++ ) {
841       x = rtmp+36*ajtmp[j];
842       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
843       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
844       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
845       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
846       x[34] = x[35] = 0.0 ;
847     }
848     /* load in initial (unfactored row) */
849     idx      = r[i];
850     nz       = ai[idx+1] - ai[idx];
851     ajtmpold = aj + ai[idx];
852     v        = aa + 36*ai[idx];
853     for ( j=0; j<nz; j++ ) {
854       x    = rtmp+36*ic[ajtmpold[j]];
855       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
856       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
857       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
858       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
859       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
860       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
861       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
862       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
863       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
864       v    += 36;
865     }
866     row = *ajtmp++;
867     while (row < i) {
868       pc  =  rtmp + 36*row;
869       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
870       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
871       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
872       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
873       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
874       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
875       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
876       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
877       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
878       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
879           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
880           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
881           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
882           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
883           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
884           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
885           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
886           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
887         pv = ba + 36*diag_offset[row];
888         pj = bj + diag_offset[row] + 1;
889 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
890 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
891 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
892 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
893 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
894 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
895 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
896 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
897 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
898         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
899         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
900         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
901         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
902         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
903         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
904 
905         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
906         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
907         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
908         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
909         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
910         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
911 
912         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
913         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
914         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
915         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
916         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
917         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
918 
919         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
920         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
921         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
922         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
923         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
924         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
925 
926         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
927         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
928         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
929         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
930         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
931         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
932 
933         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
934         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
935         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
936         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
937         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
938         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
939 
940         nz = bi[row+1] - diag_offset[row] - 1;
941         pv += 36;
942         for (j=0; j<nz; j++) {
943 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
944 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
945 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
946 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
947 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
948 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
949 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
950 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
951 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
952 	  x    = rtmp + 36*pj[j];
953           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
954           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
955           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
956           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
957           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
958           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
959 
960 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
961 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
962 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
963 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
964 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
965 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
966 
967 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
968 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
969 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
970 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
971 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
972 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
973 
974 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
975 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
976 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
977 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
978 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
979 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
980 
981 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
982 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
983 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
984 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
985 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
986 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
987 
988 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
989 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
990 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
991 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
992 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
993 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
994 
995           pv   += 36;
996         }
997         PLogFlops(432*nz+396);
998       }
999       row = *ajtmp++;
1000     }
1001     /* finished row so stick it into b->a */
1002     pv = ba + 36*bi[i];
1003     pj = bj + bi[i];
1004     nz = bi[i+1] - bi[i];
1005     for ( j=0; j<nz; j++ ) {
1006       x      = rtmp+36*pj[j];
1007       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1008       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1009       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1010       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1011       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1012       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1013       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1014       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1015       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1016       pv   += 36;
1017     }
1018     /* invert diagonal block */
1019     w = ba + 36*diag_offset[i];
1020     ierr = Kernel_A_gets_inverse_A_6(w);CHKERRQ(ierr);
1021   }
1022 
1023   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1024   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1025   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1026   C->factor = FACTOR_LU;
1027   C->assembled = PETSC_TRUE;
1028   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1029   PetscFunctionReturn(0);
1030 }
1031 /*
1032       Version for when blocks are 6 by 6 Using natural ordering
1033 */
1034 #undef __FUNC__
1035 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering"
1036 int MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat A,Mat *B)
1037 {
1038   Mat                C = *B;
1039   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1040   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1041   int                *ajtmpold, *ajtmp, nz, row;
1042   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1043   register int       *pj;
1044   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1045   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1046   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1047   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1048   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1049   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1050   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1051   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
1052   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
1053   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
1054   MatScalar          *ba = b->a,*aa = a->a;
1055 
1056   PetscFunctionBegin;
1057   rtmp  = (MatScalar *) PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1058   for ( i=0; i<n; i++ ) {
1059     nz    = bi[i+1] - bi[i];
1060     ajtmp = bj + bi[i];
1061     for  ( j=0; j<nz; j++ ) {
1062       x = rtmp+36*ajtmp[j];
1063       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1064       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1065       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
1066       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
1067       x[34] = x[35] = 0.0 ;
1068     }
1069     /* load in initial (unfactored row) */
1070     nz       = ai[i+1] - ai[i];
1071     ajtmpold = aj + ai[i];
1072     v        = aa + 36*ai[i];
1073     for ( j=0; j<nz; j++ ) {
1074       x    = rtmp+36*ajtmpold[j];
1075       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
1076       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
1077       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
1078       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
1079       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
1080       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1081       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
1082       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
1083       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
1084       v    += 36;
1085     }
1086     row = *ajtmp++;
1087     while (row < i) {
1088       pc  = rtmp + 36*row;
1089       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1090       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
1091       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
1092       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
1093       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
1094       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1095       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
1096       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
1097       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
1098       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
1099           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
1100           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
1101           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
1102           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
1103           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
1104           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
1105           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
1106           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
1107         pv = ba + 36*diag_offset[row];
1108         pj = bj + diag_offset[row] + 1;
1109 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1110 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1111 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1112 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1113 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1114 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1115 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1116 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1117 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1118         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
1119         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
1120         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
1121         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
1122         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
1123         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
1124 
1125         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
1126         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
1127         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
1128         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
1129         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
1130         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
1131 
1132         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
1133         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
1134         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
1135         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
1136         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
1137         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
1138 
1139         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
1140         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
1141         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
1142         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
1143         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
1144         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
1145 
1146         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
1147         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
1148         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
1149         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
1150         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
1151         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
1152 
1153         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
1154         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
1155         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
1156         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
1157         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
1158         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
1159 
1160         nz = bi[row+1] - diag_offset[row] - 1;
1161         pv += 36;
1162         for (j=0; j<nz; j++) {
1163 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1164 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1165 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1166 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1167 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1168 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1169 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1170 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1171 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1172 	  x    = rtmp + 36*pj[j];
1173           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
1174           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
1175           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
1176           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
1177           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
1178           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
1179 
1180 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
1181 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
1182 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
1183 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
1184 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
1185 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
1186 
1187 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
1188 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
1189 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
1190 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
1191 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
1192 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
1193 
1194 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
1195 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
1196 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
1197 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
1198 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
1199 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
1200 
1201 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
1202 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
1203 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
1204 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
1205 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
1206 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
1207 
1208 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
1209 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
1210 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
1211 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
1212 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
1213 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
1214 
1215           pv   += 36;
1216         }
1217         PLogFlops(432*nz+396);
1218       }
1219       row = *ajtmp++;
1220     }
1221     /* finished row so stick it into b->a */
1222     pv = ba + 36*bi[i];
1223     pj = bj + bi[i];
1224     nz = bi[i+1] - bi[i];
1225     for ( j=0; j<nz; j++ ) {
1226       x      = rtmp+36*pj[j];
1227       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1228       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1229       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1230       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1231       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1232       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1233       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1234       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1235       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1236       pv   += 36;
1237     }
1238     /* invert diagonal block */
1239     w = ba + 36*diag_offset[i];
1240     ierr = Kernel_A_gets_inverse_A_6(w);CHKERRQ(ierr);
1241   }
1242 
1243   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1244   C->factor    = FACTOR_LU;
1245   C->assembled = PETSC_TRUE;
1246   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1247   PetscFunctionReturn(0);
1248 }
1249 
1250 /* ------------------------------------------------------------*/
1251 /*
1252       Version for when blocks are 5 by 5
1253 */
1254 #undef __FUNC__
1255 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5"
1256 int MatLUFactorNumeric_SeqBAIJ_5(Mat A,Mat *B)
1257 {
1258   Mat                C = *B;
1259   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1260   IS                 isrow = b->row, isicol = b->icol;
1261   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1262   int                *ajtmpold, *ajtmp, nz, row;
1263   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
1264   register int       *pj;
1265   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1266   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1267   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1268   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
1269   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
1270   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1271   MatScalar          *ba = b->a,*aa = a->a;
1272 
1273   PetscFunctionBegin;
1274   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1275   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1276   rtmp  = (MatScalar *) PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1277 
1278   for ( i=0; i<n; i++ ) {
1279     nz    = bi[i+1] - bi[i];
1280     ajtmp = bj + bi[i];
1281     for  ( j=0; j<nz; j++ ) {
1282       x = rtmp+25*ajtmp[j];
1283       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1284       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1285       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1286     }
1287     /* load in initial (unfactored row) */
1288     idx      = r[i];
1289     nz       = ai[idx+1] - ai[idx];
1290     ajtmpold = aj + ai[idx];
1291     v        = aa + 25*ai[idx];
1292     for ( j=0; j<nz; j++ ) {
1293       x    = rtmp+25*ic[ajtmpold[j]];
1294       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1295       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1296       x[9] = v[9]; x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1297       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17];
1298       x[18] = v[18]; x[19] = v[19]; x[20] = v[20]; x[21] = v[21];
1299       x[22] = v[22]; x[23] = v[23]; x[24] = v[24];
1300       v    += 25;
1301     }
1302     row = *ajtmp++;
1303     while (row < i) {
1304       pc = rtmp + 25*row;
1305       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1306       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1307       p10 = pc[9]; p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1308       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17]; p19 = pc[18];
1309       p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1310       p25 = pc[24];
1311       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1312           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1313           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1314           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 ||
1315           p20 != 0.0 || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 ||
1316           p24 != 0.0 || p25 != 0.0) {
1317         pv = ba + 25*diag_offset[row];
1318         pj = bj + diag_offset[row] + 1;
1319         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1320         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1321         x10 = pv[9]; x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1322         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1323         x19 = pv[18]; x20 = pv[19]; x21 = pv[20]; x22 = pv[21];
1324         x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1325         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1326         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1327         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1328         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1329         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1330 
1331         pc[5] = m6 = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1332         pc[6] = m7 = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1333         pc[7] = m8 = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1334         pc[8] = m9 = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1335         pc[9] = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1336 
1337         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1338         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1339         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1340         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1341         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1342 
1343         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1344         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1345         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1346         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1347         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1348 
1349         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1350         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1351         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1352         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1353         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1354 
1355         nz = bi[row+1] - diag_offset[row] - 1;
1356         pv += 25;
1357         for (j=0; j<nz; j++) {
1358           x1   = pv[0];  x2 = pv[1];   x3  = pv[2];  x4  = pv[3];
1359           x5   = pv[4];  x6 = pv[5];   x7  = pv[6];  x8  = pv[7]; x9 = pv[8];
1360           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1361           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16];
1362           x18  = pv[17]; x19 = pv[18]; x20 = pv[19]; x21 = pv[20];
1363           x22  = pv[21]; x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1364           x    = rtmp + 25*pj[j];
1365           x[0] -= m1*x1 + m6*x2  + m11*x3 + m16*x4 + m21*x5;
1366           x[1] -= m2*x1 + m7*x2  + m12*x3 + m17*x4 + m22*x5;
1367           x[2] -= m3*x1 + m8*x2  + m13*x3 + m18*x4 + m23*x5;
1368           x[3] -= m4*x1 + m9*x2  + m14*x3 + m19*x4 + m24*x5;
1369           x[4] -= m5*x1 + m10*x2 + m15*x3 + m20*x4 + m25*x5;
1370 
1371           x[5] -= m1*x6 + m6*x7  + m11*x8 + m16*x9 + m21*x10;
1372           x[6] -= m2*x6 + m7*x7  + m12*x8 + m17*x9 + m22*x10;
1373           x[7] -= m3*x6 + m8*x7  + m13*x8 + m18*x9 + m23*x10;
1374           x[8] -= m4*x6 + m9*x7  + m14*x8 + m19*x9 + m24*x10;
1375           x[9] -= m5*x6 + m10*x7 + m15*x8 + m20*x9 + m25*x10;
1376 
1377           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1378           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1379           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1380           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1381           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1382 
1383           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1384           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1385           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1386           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1387           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1388 
1389           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1390           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1391           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1392           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1393           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1394 
1395           pv   += 25;
1396         }
1397         PLogFlops(250*nz+225);
1398       }
1399       row = *ajtmp++;
1400     }
1401     /* finished row so stick it into b->a */
1402     pv = ba + 25*bi[i];
1403     pj = bj + bi[i];
1404     nz = bi[i+1] - bi[i];
1405     for ( j=0; j<nz; j++ ) {
1406       x     = rtmp+25*pj[j];
1407       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1408       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1409       pv[9] = x[9]; pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1410       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16];
1411       pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20];
1412       pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23]; pv[24] = x[24];
1413       pv   += 25;
1414     }
1415     /* invert diagonal block */
1416     w = ba + 25*diag_offset[i];
1417     ierr = Kernel_A_gets_inverse_A_5(w);CHKERRQ(ierr);
1418   }
1419 
1420   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1421   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1422   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1423   C->factor = FACTOR_LU;
1424   C->assembled = PETSC_TRUE;
1425   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1426   PetscFunctionReturn(0);
1427 }
1428 /*
1429       Version for when blocks are 5 by 5 Using natural ordering
1430 */
1431 #undef __FUNC__
1432 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering"
1433 int MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering(Mat A,Mat *B)
1434 {
1435   Mat                C = *B;
1436   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1437   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1438   int                *ajtmpold, *ajtmp, nz, row;
1439   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1440   register int       *pj;
1441   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1442   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1443   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1444   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1445   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1446   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1447   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1448   MatScalar          *ba = b->a,*aa = a->a;
1449 
1450   PetscFunctionBegin;
1451   rtmp  = (MatScalar *) PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1452   for ( i=0; i<n; i++ ) {
1453     nz    = bi[i+1] - bi[i];
1454     ajtmp = bj + bi[i];
1455     for  ( j=0; j<nz; j++ ) {
1456       x = rtmp+25*ajtmp[j];
1457       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1458       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1459       x[16] = x[17] = x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1460     }
1461     /* load in initial (unfactored row) */
1462     nz       = ai[i+1] - ai[i];
1463     ajtmpold = aj + ai[i];
1464     v        = aa + 25*ai[i];
1465     for ( j=0; j<nz; j++ ) {
1466       x    = rtmp+25*ajtmpold[j];
1467       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1468       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1469       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1470       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17]; x[18] = v[18];
1471       x[19] = v[19]; x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1472       x[24] = v[24];
1473       v    += 25;
1474     }
1475     row = *ajtmp++;
1476     while (row < i) {
1477       pc  = rtmp + 25*row;
1478       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1479       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1480       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1481       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17];
1482       p19 = pc[18]; p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22];
1483       p24 = pc[23]; p25 = pc[24];
1484       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1485           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1486           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1487           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0
1488           || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 || p25 != 0.0) {
1489         pv = ba + 25*diag_offset[row];
1490         pj = bj + diag_offset[row] + 1;
1491         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1492         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1493         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1494         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17]; x19 = pv[18];
1495         x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1496         x25 = pv[24];
1497         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1498         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1499         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1500         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1501         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1502 
1503         pc[5]  = m6  = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1504         pc[6]  = m7  = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1505         pc[7]  = m8  = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1506         pc[8]  = m9  = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1507         pc[9]  = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1508 
1509         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1510         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1511         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1512         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1513         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1514 
1515         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1516         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1517         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1518         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1519         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1520 
1521         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1522         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1523         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1524         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1525         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1526 
1527         nz = bi[row+1] - diag_offset[row] - 1;
1528         pv += 25;
1529         for (j=0; j<nz; j++) {
1530           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1531           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1532           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1533           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1534           x19 = pv[18];  x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22];
1535           x24 = pv[23];  x25 = pv[24];
1536           x    = rtmp + 25*pj[j];
1537           x[0] -= m1*x1 + m6*x2   + m11*x3  + m16*x4 + m21*x5;
1538           x[1] -= m2*x1 + m7*x2   + m12*x3  + m17*x4 + m22*x5;
1539           x[2] -= m3*x1 + m8*x2   + m13*x3  + m18*x4 + m23*x5;
1540           x[3] -= m4*x1 + m9*x2   + m14*x3  + m19*x4 + m24*x5;
1541           x[4] -= m5*x1 + m10*x2  + m15*x3  + m20*x4 + m25*x5;
1542 
1543           x[5] -= m1*x6 + m6*x7   + m11*x8  + m16*x9 + m21*x10;
1544           x[6] -= m2*x6 + m7*x7   + m12*x8  + m17*x9 + m22*x10;
1545           x[7] -= m3*x6 + m8*x7   + m13*x8  + m18*x9 + m23*x10;
1546           x[8] -= m4*x6 + m9*x7   + m14*x8  + m19*x9 + m24*x10;
1547           x[9] -= m5*x6 + m10*x7  + m15*x8  + m20*x9 + m25*x10;
1548 
1549           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1550           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1551           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1552           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1553           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1554 
1555           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1556           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1557           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1558           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1559           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1560 
1561           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1562           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1563           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1564           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1565           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1566           pv   += 25;
1567         }
1568         PLogFlops(250*nz+225);
1569       }
1570       row = *ajtmp++;
1571     }
1572     /* finished row so stick it into b->a */
1573     pv = ba + 25*bi[i];
1574     pj = bj + bi[i];
1575     nz = bi[i+1] - bi[i];
1576     for ( j=0; j<nz; j++ ) {
1577       x      = rtmp+25*pj[j];
1578       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1579       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1580       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1581       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16]; pv[17] = x[17];
1582       pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22];
1583       pv[23] = x[23]; pv[24] = x[24];
1584       pv   += 25;
1585     }
1586     /* invert diagonal block */
1587     w = ba + 25*diag_offset[i];
1588     ierr = Kernel_A_gets_inverse_A_5(w);CHKERRQ(ierr);
1589   }
1590 
1591   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1592   C->factor    = FACTOR_LU;
1593   C->assembled = PETSC_TRUE;
1594   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1595   PetscFunctionReturn(0);
1596 }
1597 
1598 /* ------------------------------------------------------------*/
1599 /*
1600       Version for when blocks are 4 by 4
1601 */
1602 #undef __FUNC__
1603 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4"
1604 int MatLUFactorNumeric_SeqBAIJ_4(Mat A,Mat *B)
1605 {
1606   Mat                C = *B;
1607   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1608   IS                 isrow = b->row, isicol = b->icol;
1609   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1610   int                *ajtmpold, *ajtmp, nz, row;
1611   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
1612   register int       *pj;
1613   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1614   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1615   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1616   MatScalar          p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
1617   MatScalar          m13,m14,m15,m16;
1618   MatScalar          *ba = b->a,*aa = a->a;
1619 
1620   PetscFunctionBegin;
1621   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1622   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1623   rtmp  = (MatScalar *) PetscMalloc(16*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1624 
1625   for ( i=0; i<n; i++ ) {
1626     nz    = bi[i+1] - bi[i];
1627     ajtmp = bj + bi[i];
1628     for  ( j=0; j<nz; j++ ) {
1629       x = rtmp+16*ajtmp[j];
1630       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1631       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1632     }
1633     /* load in initial (unfactored row) */
1634     idx      = r[i];
1635     nz       = ai[idx+1] - ai[idx];
1636     ajtmpold = aj + ai[idx];
1637     v        = aa + 16*ai[idx];
1638     for ( j=0; j<nz; j++ ) {
1639       x    = rtmp+16*ic[ajtmpold[j]];
1640       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1641       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1642       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1643       x[14] = v[14]; x[15] = v[15];
1644       v    += 16;
1645     }
1646     row = *ajtmp++;
1647     while (row < i) {
1648       pc  = rtmp + 16*row;
1649       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1650       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1651       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1652       p15 = pc[14]; p16 = pc[15];
1653       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1654           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1655           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1656           || p16 != 0.0) {
1657         pv = ba + 16*diag_offset[row];
1658         pj = bj + diag_offset[row] + 1;
1659         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1660         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1661         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1662         x15 = pv[14]; x16 = pv[15];
1663         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
1664         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
1665         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
1666         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
1667 
1668         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
1669         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
1670         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
1671         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
1672 
1673         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
1674         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
1675         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
1676         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
1677 
1678         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
1679         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
1680         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
1681         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
1682 
1683         nz = bi[row+1] - diag_offset[row] - 1;
1684         pv += 16;
1685         for (j=0; j<nz; j++) {
1686           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1687           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1688           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1689           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
1690           x    = rtmp + 16*pj[j];
1691           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
1692           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
1693           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
1694           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
1695 
1696           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
1697           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
1698           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
1699           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
1700 
1701           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
1702           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
1703           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
1704           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
1705 
1706           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
1707           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
1708           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
1709           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
1710 
1711           pv   += 16;
1712         }
1713         PLogFlops(128*nz+112);
1714       }
1715       row = *ajtmp++;
1716     }
1717     /* finished row so stick it into b->a */
1718     pv = ba + 16*bi[i];
1719     pj = bj + bi[i];
1720     nz = bi[i+1] - bi[i];
1721     for ( j=0; j<nz; j++ ) {
1722       x      = rtmp+16*pj[j];
1723       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1724       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1725       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1726       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1727       pv   += 16;
1728     }
1729     /* invert diagonal block */
1730     w = ba + 16*diag_offset[i];
1731     ierr = Kernel_A_gets_inverse_A_4(w);CHKERRQ(ierr);
1732   }
1733 
1734   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1735   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1736   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1737   C->factor = FACTOR_LU;
1738   C->assembled = PETSC_TRUE;
1739   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
1740   PetscFunctionReturn(0);
1741 }
1742 /*
1743       Version for when blocks are 4 by 4 Using natural ordering
1744 */
1745 #undef __FUNC__
1746 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering"
1747 int MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering(Mat A,Mat *B)
1748 {
1749   Mat                C = *B;
1750   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1751   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1752   int                *ajtmpold, *ajtmp, nz, row;
1753   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1754   register int       *pj;
1755   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1756   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1757   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1758   MatScalar          p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
1759   MatScalar          m13,m14,m15,m16;
1760   MatScalar          *ba = b->a,*aa = a->a;
1761 
1762   PetscFunctionBegin;
1763   rtmp  = (MatScalar *) PetscMalloc(16*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1764 
1765   for ( i=0; i<n; i++ ) {
1766     nz    = bi[i+1] - bi[i];
1767     ajtmp = bj + bi[i];
1768     for  ( j=0; j<nz; j++ ) {
1769       x = rtmp+16*ajtmp[j];
1770       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1771       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1772     }
1773     /* load in initial (unfactored row) */
1774     nz       = ai[i+1] - ai[i];
1775     ajtmpold = aj + ai[i];
1776     v        = aa + 16*ai[i];
1777     for ( j=0; j<nz; j++ ) {
1778       x    = rtmp+16*ajtmpold[j];
1779       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1780       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1781       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1782       x[14] = v[14]; x[15] = v[15];
1783       v    += 16;
1784     }
1785     row = *ajtmp++;
1786     while (row < i) {
1787       pc  = rtmp + 16*row;
1788       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1789       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1790       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1791       p15 = pc[14]; p16 = pc[15];
1792       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1793           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1794           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1795           || p16 != 0.0) {
1796         pv = ba + 16*diag_offset[row];
1797         pj = bj + diag_offset[row] + 1;
1798         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1799         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1800         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1801         x15 = pv[14]; x16 = pv[15];
1802         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
1803         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
1804         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
1805         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
1806 
1807         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
1808         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
1809         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
1810         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
1811 
1812         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
1813         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
1814         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
1815         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
1816 
1817         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
1818         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
1819         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
1820         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
1821 
1822         nz = bi[row+1] - diag_offset[row] - 1;
1823         pv += 16;
1824         for (j=0; j<nz; j++) {
1825           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1826           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1827           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1828           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
1829           x    = rtmp + 16*pj[j];
1830           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
1831           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
1832           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
1833           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
1834 
1835           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
1836           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
1837           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
1838           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
1839 
1840           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
1841           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
1842           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
1843           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
1844 
1845           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
1846           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
1847           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
1848           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
1849 
1850           pv   += 16;
1851         }
1852         PLogFlops(128*nz+112);
1853       }
1854       row = *ajtmp++;
1855     }
1856     /* finished row so stick it into b->a */
1857     pv = ba + 16*bi[i];
1858     pj = bj + bi[i];
1859     nz = bi[i+1] - bi[i];
1860     for ( j=0; j<nz; j++ ) {
1861       x      = rtmp+16*pj[j];
1862       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1863       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1864       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1865       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1866       pv   += 16;
1867     }
1868     /* invert diagonal block */
1869     w = ba + 16*diag_offset[i];
1870     ierr = Kernel_A_gets_inverse_A_4(w);CHKERRQ(ierr);
1871   }
1872 
1873   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1874   C->factor    = FACTOR_LU;
1875   C->assembled = PETSC_TRUE;
1876   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
1877   PetscFunctionReturn(0);
1878 }
1879 
1880 
1881 /* ------------------------------------------------------------*/
1882 /*
1883       Version for when blocks are 3 by 3
1884 */
1885 #undef __FUNC__
1886 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3"
1887 int MatLUFactorNumeric_SeqBAIJ_3(Mat A,Mat *B)
1888 {
1889   Mat                C = *B;
1890   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1891   IS                 isrow = b->row, isicol = b->icol;
1892   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1893   int                *ajtmpold, *ajtmp, nz, row, *ai=a->i,*aj=a->j;
1894   int                *diag_offset = b->diag,idx;
1895   register int       *pj;
1896   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1897   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1898   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
1899   MatScalar          *ba = b->a,*aa = a->a;
1900 
1901   PetscFunctionBegin;
1902   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1903   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1904   rtmp  = (MatScalar *) PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1905 
1906   for ( i=0; i<n; i++ ) {
1907     nz    = bi[i+1] - bi[i];
1908     ajtmp = bj + bi[i];
1909     for  ( j=0; j<nz; j++ ) {
1910       x = rtmp + 9*ajtmp[j];
1911       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = 0.0;
1912     }
1913     /* load in initial (unfactored row) */
1914     idx      = r[i];
1915     nz       = ai[idx+1] - ai[idx];
1916     ajtmpold = aj + ai[idx];
1917     v        = aa + 9*ai[idx];
1918     for ( j=0; j<nz; j++ ) {
1919       x    = rtmp + 9*ic[ajtmpold[j]];
1920       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1921       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1922       v    += 9;
1923     }
1924     row = *ajtmp++;
1925     while (row < i) {
1926       pc = rtmp + 9*row;
1927       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1928       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1929       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1930           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
1931         pv = ba + 9*diag_offset[row];
1932         pj = bj + diag_offset[row] + 1;
1933         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1934         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1935         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
1936         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
1937         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
1938 
1939         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
1940         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
1941         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
1942 
1943         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
1944         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
1945         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
1946         nz = bi[row+1] - diag_offset[row] - 1;
1947         pv += 9;
1948         for (j=0; j<nz; j++) {
1949           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1950           x5   = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1951           x    = rtmp + 9*pj[j];
1952           x[0] -= m1*x1 + m4*x2 + m7*x3;
1953           x[1] -= m2*x1 + m5*x2 + m8*x3;
1954           x[2] -= m3*x1 + m6*x2 + m9*x3;
1955 
1956           x[3] -= m1*x4 + m4*x5 + m7*x6;
1957           x[4] -= m2*x4 + m5*x5 + m8*x6;
1958           x[5] -= m3*x4 + m6*x5 + m9*x6;
1959 
1960           x[6] -= m1*x7 + m4*x8 + m7*x9;
1961           x[7] -= m2*x7 + m5*x8 + m8*x9;
1962           x[8] -= m3*x7 + m6*x8 + m9*x9;
1963           pv   += 9;
1964         }
1965         PLogFlops(54*nz+36);
1966       }
1967       row = *ajtmp++;
1968     }
1969     /* finished row so stick it into b->a */
1970     pv = ba + 9*bi[i];
1971     pj = bj + bi[i];
1972     nz = bi[i+1] - bi[i];
1973     for ( j=0; j<nz; j++ ) {
1974       x     = rtmp + 9*pj[j];
1975       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1976       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1977       pv   += 9;
1978     }
1979     /* invert diagonal block */
1980     w = ba + 9*diag_offset[i];
1981     ierr = Kernel_A_gets_inverse_A_3(w);CHKERRQ(ierr);
1982   }
1983 
1984   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1985   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1986   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1987   C->factor = FACTOR_LU;
1988   C->assembled = PETSC_TRUE;
1989   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
1990   PetscFunctionReturn(0);
1991 }
1992 /*
1993       Version for when blocks are 3 by 3 Using natural ordering
1994 */
1995 #undef __FUNC__
1996 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering"
1997 int MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering(Mat A,Mat *B)
1998 {
1999   Mat                C = *B;
2000   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
2001   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2002   int                *ajtmpold, *ajtmp, nz, row;
2003   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
2004   register int       *pj;
2005   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
2006   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
2007   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
2008   MatScalar          *ba = b->a,*aa = a->a;
2009 
2010   PetscFunctionBegin;
2011   rtmp  = (MatScalar *) PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2012 
2013   for ( i=0; i<n; i++ ) {
2014     nz    = bi[i+1] - bi[i];
2015     ajtmp = bj + bi[i];
2016     for  ( j=0; j<nz; j++ ) {
2017       x = rtmp+9*ajtmp[j];
2018       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = 0.0;
2019     }
2020     /* load in initial (unfactored row) */
2021     nz       = ai[i+1] - ai[i];
2022     ajtmpold = aj + ai[i];
2023     v        = aa + 9*ai[i];
2024     for ( j=0; j<nz; j++ ) {
2025       x    = rtmp+9*ajtmpold[j];
2026       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2027       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
2028       v    += 9;
2029     }
2030     row = *ajtmp++;
2031     while (row < i) {
2032       pc  = rtmp + 9*row;
2033       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2034       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
2035       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
2036           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
2037         pv = ba + 9*diag_offset[row];
2038         pj = bj + diag_offset[row] + 1;
2039         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2040         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
2041         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
2042         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
2043         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
2044 
2045         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
2046         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
2047         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
2048 
2049         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
2050         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
2051         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
2052 
2053         nz = bi[row+1] - diag_offset[row] - 1;
2054         pv += 9;
2055         for (j=0; j<nz; j++) {
2056           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2057           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
2058           x    = rtmp + 9*pj[j];
2059           x[0] -= m1*x1 + m4*x2 + m7*x3;
2060           x[1] -= m2*x1 + m5*x2 + m8*x3;
2061           x[2] -= m3*x1 + m6*x2 + m9*x3;
2062 
2063           x[3] -= m1*x4 + m4*x5 + m7*x6;
2064           x[4] -= m2*x4 + m5*x5 + m8*x6;
2065           x[5] -= m3*x4 + m6*x5 + m9*x6;
2066 
2067           x[6] -= m1*x7 + m4*x8 + m7*x9;
2068           x[7] -= m2*x7 + m5*x8 + m8*x9;
2069           x[8] -= m3*x7 + m6*x8 + m9*x9;
2070           pv   += 9;
2071         }
2072         PLogFlops(54*nz+36);
2073       }
2074       row = *ajtmp++;
2075     }
2076     /* finished row so stick it into b->a */
2077     pv = ba + 9*bi[i];
2078     pj = bj + bi[i];
2079     nz = bi[i+1] - bi[i];
2080     for ( j=0; j<nz; j++ ) {
2081       x      = rtmp+9*pj[j];
2082       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2083       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
2084       pv   += 9;
2085     }
2086     /* invert diagonal block */
2087     w = ba + 9*diag_offset[i];
2088     ierr = Kernel_A_gets_inverse_A_3(w);CHKERRQ(ierr);
2089   }
2090 
2091   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2092   C->factor    = FACTOR_LU;
2093   C->assembled = PETSC_TRUE;
2094   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
2095   PetscFunctionReturn(0);
2096 }
2097 
2098 /* ------------------------------------------------------------*/
2099 /*
2100       Version for when blocks are 2 by 2
2101 */
2102 #undef __FUNC__
2103 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2"
2104 int MatLUFactorNumeric_SeqBAIJ_2(Mat A,Mat *B)
2105 {
2106   Mat                C = *B;
2107   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
2108   IS                 isrow = b->row, isicol = b->icol;
2109   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2110   int                *ajtmpold, *ajtmp, nz, row;
2111   int                *diag_offset=b->diag,idx,*ai=a->i,*aj=a->j;
2112   register int       *pj;
2113   register MatScalar *pv,*v,*rtmp,m1,m2,m3,m4,*pc,*w,*x,x1,x2,x3,x4;
2114   MatScalar          p1,p2,p3,p4;
2115   MatScalar          *ba = b->a,*aa = a->a;
2116 
2117   PetscFunctionBegin;
2118   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
2119   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
2120   rtmp  = (MatScalar *) PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2121 
2122   for ( i=0; i<n; i++ ) {
2123     nz    = bi[i+1] - bi[i];
2124     ajtmp = bj + bi[i];
2125     for  ( j=0; j<nz; j++ ) {
2126       x = rtmp+4*ajtmp[j]; x[0] = x[1] = x[2] = x[3] = 0.0;
2127     }
2128     /* load in initial (unfactored row) */
2129     idx      = r[i];
2130     nz       = ai[idx+1] - ai[idx];
2131     ajtmpold = aj + ai[idx];
2132     v        = aa + 4*ai[idx];
2133     for ( j=0; j<nz; j++ ) {
2134       x    = rtmp+4*ic[ajtmpold[j]];
2135       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
2136       v    += 4;
2137     }
2138     row = *ajtmp++;
2139     while (row < i) {
2140       pc = rtmp + 4*row;
2141       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
2142       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2143         pv = ba + 4*diag_offset[row];
2144         pj = bj + diag_offset[row] + 1;
2145         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2146         pc[0] = m1 = p1*x1 + p3*x2;
2147         pc[1] = m2 = p2*x1 + p4*x2;
2148         pc[2] = m3 = p1*x3 + p3*x4;
2149         pc[3] = m4 = p2*x3 + p4*x4;
2150         nz = bi[row+1] - diag_offset[row] - 1;
2151         pv += 4;
2152         for (j=0; j<nz; j++) {
2153           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2154           x    = rtmp + 4*pj[j];
2155           x[0] -= m1*x1 + m3*x2;
2156           x[1] -= m2*x1 + m4*x2;
2157           x[2] -= m1*x3 + m3*x4;
2158           x[3] -= m2*x3 + m4*x4;
2159           pv   += 4;
2160         }
2161         PLogFlops(16*nz+12);
2162       }
2163       row = *ajtmp++;
2164     }
2165     /* finished row so stick it into b->a */
2166     pv = ba + 4*bi[i];
2167     pj = bj + bi[i];
2168     nz = bi[i+1] - bi[i];
2169     for ( j=0; j<nz; j++ ) {
2170       x     = rtmp+4*pj[j];
2171       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
2172       pv   += 4;
2173     }
2174     /* invert diagonal block */
2175     w = ba + 4*diag_offset[i];
2176     ierr = Kernel_A_gets_inverse_A_2(w);CHKERRQ(ierr);
2177     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2178   }
2179 
2180   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2181   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
2182   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
2183   C->factor = FACTOR_LU;
2184   C->assembled = PETSC_TRUE;
2185   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2186   PetscFunctionReturn(0);
2187 }
2188 /*
2189       Version for when blocks are 2 by 2 Using natural ordering
2190 */
2191 #undef __FUNC__
2192 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering"
2193 int MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering(Mat A,Mat *B)
2194 {
2195   Mat                C = *B;
2196   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
2197   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2198   int                *ajtmpold, *ajtmp, nz, row;
2199   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
2200   register int       *pj;
2201   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
2202   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,x1,x2,x3,x4;
2203   MatScalar          *ba = b->a,*aa = a->a;
2204 
2205   PetscFunctionBegin;
2206   rtmp  = (MatScalar *) PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2207 
2208   for ( i=0; i<n; i++ ) {
2209     nz    = bi[i+1] - bi[i];
2210     ajtmp = bj + bi[i];
2211     for  ( j=0; j<nz; j++ ) {
2212       x = rtmp+4*ajtmp[j];
2213       x[0]  = x[1]  = x[2]  = x[3]  = 0.0;
2214     }
2215     /* load in initial (unfactored row) */
2216     nz       = ai[i+1] - ai[i];
2217     ajtmpold = aj + ai[i];
2218     v        = aa + 4*ai[i];
2219     for ( j=0; j<nz; j++ ) {
2220       x    = rtmp+4*ajtmpold[j];
2221       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2222       v    += 4;
2223     }
2224     row = *ajtmp++;
2225     while (row < i) {
2226       pc  = rtmp + 4*row;
2227       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2228       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2229         pv = ba + 4*diag_offset[row];
2230         pj = bj + diag_offset[row] + 1;
2231         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2232         pc[0] = m1 = p1*x1 + p3*x2;
2233         pc[1] = m2 = p2*x1 + p4*x2;
2234         pc[2] = m3 = p1*x3 + p3*x4;
2235         pc[3] = m4 = p2*x3 + p4*x4;
2236         nz = bi[row+1] - diag_offset[row] - 1;
2237         pv += 4;
2238         for (j=0; j<nz; j++) {
2239           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2240           x    = rtmp + 4*pj[j];
2241           x[0] -= m1*x1 + m3*x2;
2242           x[1] -= m2*x1 + m4*x2;
2243           x[2] -= m1*x3 + m3*x4;
2244           x[3] -= m2*x3 + m4*x4;
2245           pv   += 4;
2246         }
2247         PLogFlops(16*nz+12);
2248       }
2249       row = *ajtmp++;
2250     }
2251     /* finished row so stick it into b->a */
2252     pv = ba + 4*bi[i];
2253     pj = bj + bi[i];
2254     nz = bi[i+1] - bi[i];
2255     for ( j=0; j<nz; j++ ) {
2256       x      = rtmp+4*pj[j];
2257       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2258       pv   += 4;
2259     }
2260     /* invert diagonal block */
2261     w = ba + 4*diag_offset[i];
2262     ierr = Kernel_A_gets_inverse_A_2(w);CHKERRQ(ierr);
2263     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2264   }
2265 
2266   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2267   C->factor    = FACTOR_LU;
2268   C->assembled = PETSC_TRUE;
2269   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2270   PetscFunctionReturn(0);
2271 }
2272 
2273 /* ----------------------------------------------------------- */
2274 /*
2275      Version for when blocks are 1 by 1.
2276 */
2277 #undef __FUNC__
2278 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_1"
2279 int MatLUFactorNumeric_SeqBAIJ_1(Mat A,Mat *B)
2280 {
2281   Mat                C = *B;
2282   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data, *b = (Mat_SeqBAIJ *)C->data;
2283   IS                 isrow = b->row, isicol = b->icol;
2284   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2285   int                *ajtmpold, *ajtmp, nz, row,*ai = a->i,*aj = a->j;
2286   int                *diag_offset = b->diag,diag;
2287   register int       *pj;
2288   register MatScalar *pv,*v,*rtmp,multiplier,*pc;
2289   MatScalar          *ba = b->a,*aa = a->a;
2290 
2291   PetscFunctionBegin;
2292   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
2293   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
2294   rtmp  = (MatScalar *) PetscMalloc((n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2295 
2296   for ( i=0; i<n; i++ ) {
2297     nz    = bi[i+1] - bi[i];
2298     ajtmp = bj + bi[i];
2299     for  ( j=0; j<nz; j++ ) rtmp[ajtmp[j]] = 0.0;
2300 
2301     /* load in initial (unfactored row) */
2302     nz       = ai[r[i]+1] - ai[r[i]];
2303     ajtmpold = aj + ai[r[i]];
2304     v        = aa + ai[r[i]];
2305     for ( j=0; j<nz; j++ ) rtmp[ic[ajtmpold[j]]] =  v[j];
2306 
2307     row = *ajtmp++;
2308     while (row < i) {
2309       pc = rtmp + row;
2310       if (*pc != 0.0) {
2311         pv         = ba + diag_offset[row];
2312         pj         = bj + diag_offset[row] + 1;
2313         multiplier = *pc * *pv++;
2314         *pc        = multiplier;
2315         nz         = bi[row+1] - diag_offset[row] - 1;
2316         for (j=0; j<nz; j++) rtmp[pj[j]] -= multiplier * pv[j];
2317         PLogFlops(1+2*nz);
2318       }
2319       row = *ajtmp++;
2320     }
2321     /* finished row so stick it into b->a */
2322     pv = ba + bi[i];
2323     pj = bj + bi[i];
2324     nz = bi[i+1] - bi[i];
2325     for ( j=0; j<nz; j++ ) {pv[j] = rtmp[pj[j]];}
2326     diag = diag_offset[i] - bi[i];
2327     /* check pivot entry for current row */
2328     if (pv[diag] == 0.0) {
2329       SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,0,"Zero pivot");
2330     }
2331     pv[diag] = 1.0/pv[diag];
2332   }
2333 
2334   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2335   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
2336   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
2337   C->factor    = FACTOR_LU;
2338   C->assembled = PETSC_TRUE;
2339   PLogFlops(b->n);
2340   PetscFunctionReturn(0);
2341 }
2342 
2343 /* ----------------------------------------------------------- */
2344 #undef __FUNC__
2345 #define __FUNC__ "MatLUFactor_SeqBAIJ"
2346 int MatLUFactor_SeqBAIJ(Mat A,IS row,IS col,double f)
2347 {
2348   Mat_SeqBAIJ    *mat = (Mat_SeqBAIJ *) A->data;
2349   int            ierr;
2350   Mat            C;
2351   PetscOps *Abops;
2352   MatOps   Aops;
2353 
2354   PetscFunctionBegin;
2355   ierr = MatLUFactorSymbolic(A,row,col,f,&C);CHKERRQ(ierr);
2356   ierr = MatLUFactorNumeric(A,&C);CHKERRQ(ierr);
2357 
2358   /* free all the data structures from mat */
2359   ierr = PetscFree(mat->a);CHKERRQ(ierr);
2360   if (!mat->singlemalloc) {
2361     ierr = PetscFree(mat->i);CHKERRQ(ierr);
2362     ierr = PetscFree(mat->j);CHKERRQ(ierr);
2363   }
2364   if (mat->diag) {ierr = PetscFree(mat->diag);CHKERRQ(ierr);}
2365   if (mat->ilen) {ierr = PetscFree(mat->ilen);CHKERRQ(ierr);}
2366   if (mat->imax) {ierr = PetscFree(mat->imax);CHKERRQ(ierr);}
2367   if (mat->solve_work) {ierr = PetscFree(mat->solve_work);CHKERRQ(ierr);}
2368   if (mat->mult_work) {ierr = PetscFree(mat->mult_work);CHKERRQ(ierr);}
2369   if (mat->icol) {ierr = ISDestroy(mat->icol);CHKERRQ(ierr);}
2370   ierr = PetscFree(mat);CHKERRQ(ierr);
2371 
2372   ierr = MapDestroy(A->rmap);CHKERRQ(ierr);
2373   ierr = MapDestroy(A->cmap);CHKERRQ(ierr);
2374 
2375   /*
2376        This is horrible, horrible code. We need to keep the
2377     A pointers for the bops and ops but copy everything
2378     else from C.
2379   */
2380   Abops = A->bops;
2381   Aops  = A->ops;
2382   ierr  = PetscMemcpy(A,C,sizeof(struct _p_Mat));CHKERRQ(ierr);
2383   mat   = (Mat_SeqBAIJ *) A->data;
2384   PLogObjectParent(A,mat->icol);
2385 
2386   A->bops  = Abops;
2387   A->ops   = Aops;
2388   A->qlist = 0;
2389 
2390   PetscHeaderDestroy(C);
2391   PetscFunctionReturn(0);
2392 }
2393 
2394 
2395 
2396