xref: /petsc/src/mat/impls/baij/seq/baijfact.c (revision 2515f8d2605083ac68be12fdb9975c088e8e83c4)
1 #ifdef PETSC_RCS_HEADER
2 static char vcid[] = "$Id: baijfact.c,v 1.70 1999/03/17 23:23:13 bsmith 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       PetscMemcpy(ajtmp,ajnew,ainew[i]*sizeof(int));
101       PetscFree(ajnew);
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   PetscFree(fill);
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   PetscFree(b->imax);
138   b->singlemalloc = 0;
139   /* the next line frees the default space generated by the Create() */
140   PetscFree(b->a); PetscFree(b->ilen);
141   b->a          = (MatScalar *) PetscMalloc((ainew[n]+1)*sizeof(MatScalar)*bs2);CHKPTRQ(b->a);
142   b->j          = ajnew;
143   b->i          = ainew;
144   b->diag       = idnew;
145   b->ilen       = 0;
146   b->imax       = 0;
147   b->row        = isrow;
148   b->col        = iscol;
149   b->icol       = isicol;
150   b->solve_work = (Scalar *) PetscMalloc( (bs*n+bs)*sizeof(Scalar));CHKPTRQ(b->solve_work);
151   /* In b structure:  Free imax, ilen, old a, old j.
152      Allocate idnew, solve_work, new a, new j */
153   PLogObjectMemory(*B,(ainew[n]-n)*(sizeof(int)+sizeof(MatScalar)));
154   b->maxnz = b->nz = ainew[n];
155 
156   (*B)->factor                 = FACTOR_LU;
157   (*B)->info.factor_mallocs    = realloc;
158   (*B)->info.fill_ratio_given  = f;
159   if (ai[n] != 0) {
160     (*B)->info.fill_ratio_needed = ((double)ainew[n])/((double)ai[n]);
161   } else {
162     (*B)->info.fill_ratio_needed = 0.0;
163   }
164 
165 
166   PetscFunctionReturn(0);
167 }
168 
169 /* ----------------------------------------------------------- */
170 #undef __FUNC__
171 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_N"
172 int MatLUFactorNumeric_SeqBAIJ_N(Mat A,Mat *B)
173 {
174   Mat                C = *B;
175   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
176   IS                 isrow = b->row, isicol = b->icol;
177   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
178   int                *ajtmpold, *ajtmp, nz, row, bslog,*ai=a->i,*aj=a->j,k,flg;
179   int                *diag_offset=b->diag,diag,bs=a->bs,bs2 = a->bs2,*v_pivots;
180   register int       *pj;
181   register MatScalar *pv,*v,*rtmp,*multiplier,*v_work,*pc,*w;
182   MatScalar          *ba = b->a,*aa = a->a;
183 
184   PetscFunctionBegin;
185   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
186   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
187   rtmp  = (MatScalar *) PetscMalloc(bs2*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
188   PetscMemzero(rtmp,bs2*(n+1)*sizeof(MatScalar));
189   /* generate work space needed by dense LU factorization */
190   v_work     = (MatScalar *) PetscMalloc(bs*sizeof(int) + (bs+bs2)*sizeof(MatScalar));CHKPTRQ(v_work);
191   multiplier = v_work + bs;
192   v_pivots   = (int *) (multiplier + bs2);
193 
194   /* flops in while loop */
195   bslog = 2*bs*bs2;
196 
197   for ( i=0; i<n; i++ ) {
198     nz    = bi[i+1] - bi[i];
199     ajtmp = bj + bi[i];
200     for  ( j=0; j<nz; j++ ) {
201       PetscMemzero(rtmp+bs2*ajtmp[j],bs2*sizeof(MatScalar));
202     }
203     /* load in initial (unfactored row) */
204     nz       = ai[r[i]+1] - ai[r[i]];
205     ajtmpold = aj + ai[r[i]];
206     v        = aa + bs2*ai[r[i]];
207     for ( j=0; j<nz; j++ ) {
208       PetscMemcpy(rtmp+bs2*ic[ajtmpold[j]],v+bs2*j,bs2*sizeof(MatScalar));
209     }
210     row = *ajtmp++;
211     while (row < i) {
212       pc = rtmp + bs2*row;
213 /*      if (*pc) { */
214       for ( flg=0,k=0; k<bs2; k++ ) { if (pc[k]!=0.0) { flg =1; break; }}
215       if (flg) {
216         pv = ba + bs2*diag_offset[row];
217         pj = bj + diag_offset[row] + 1;
218         Kernel_A_gets_A_times_B(bs,pc,pv,multiplier);
219         nz = bi[row+1] - diag_offset[row] - 1;
220         pv += bs2;
221         for (j=0; j<nz; j++) {
222           Kernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j);
223         }
224         PLogFlops(bslog*(nz+1)-bs);
225       }
226         row = *ajtmp++;
227     }
228     /* finished row so stick it into b->a */
229     pv = ba + bs2*bi[i];
230     pj = bj + bi[i];
231     nz = bi[i+1] - bi[i];
232     for ( j=0; j<nz; j++ ) {
233       PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));
234     }
235     diag = diag_offset[i] - bi[i];
236     /* invert diagonal block */
237     w = pv + bs2*diag;
238     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
239   }
240 
241   PetscFree(rtmp); PetscFree(v_work);
242   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
243   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
244   C->factor = FACTOR_LU;
245   C->assembled = PETSC_TRUE;
246   PLogFlops(1.3333*bs*bs2*b->mbs); /* from inverting diagonal blocks */
247   PetscFunctionReturn(0);
248 }
249 /* ------------------------------------------------------------*/
250 /*
251       Version for when blocks are 7 by 7
252 */
253 #undef __FUNC__
254 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7"
255 int MatLUFactorNumeric_SeqBAIJ_7(Mat A,Mat *B)
256 {
257   Mat                C = *B;
258   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
259   IS                 isrow = b->row, isicol = b->icol;
260   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
261   int                *ajtmpold, *ajtmp, nz, row;
262   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
263   register int       *pj;
264   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
265   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
266   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
267   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
268   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
269   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
270   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
271   MatScalar          p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
272   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
273   MatScalar          x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
274   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
275   MatScalar          m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
276   MatScalar          *ba = b->a,*aa = a->a;
277 
278   PetscFunctionBegin;
279   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
280   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
281   rtmp  = (MatScalar *) PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
282 
283   for ( i=0; i<n; i++ ) {
284     nz    = bi[i+1] - bi[i];
285     ajtmp = bj + bi[i];
286     for  ( j=0; j<nz; j++ ) {
287       x = rtmp+49*ajtmp[j];
288       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
289       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
290       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
291       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
292       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
293       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
294     }
295     /* load in initial (unfactored row) */
296     idx      = r[i];
297     nz       = ai[idx+1] - ai[idx];
298     ajtmpold = aj + ai[idx];
299     v        = aa + 49*ai[idx];
300     for ( j=0; j<nz; j++ ) {
301       x    = rtmp+49*ic[ajtmpold[j]];
302       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
303       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
304       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
305       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
306       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
307       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
308       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
309       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
310       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
311       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
312       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
313       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
314       x[48] = v[48];
315       v    += 49;
316     }
317     row = *ajtmp++;
318     while (row < i) {
319       pc  =  rtmp + 49*row;
320       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
321       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
322       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
323       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
324       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
325       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
326       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
327       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
328       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
329       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
330       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
331       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
332       p49 = pc[48];
333       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
334           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
335           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
336           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
337           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
338           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
339           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
340           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
341           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
342           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
343           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
344           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
345           p49 != 0.0) {
346         pv = ba + 49*diag_offset[row];
347         pj = bj + diag_offset[row] + 1;
348 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
349 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
350 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
351 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
352 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
353 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
354 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
355 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
356 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
357 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
358 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
359 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
360 	x49 = pv[48];
361         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
362         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
363         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
364         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
365         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
366         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
367         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
368 
369         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
370         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
371         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
372         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
373         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
374         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
375         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
376 
377         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
378         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
379         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
380         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
381         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
382         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
383         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
384 
385         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
386         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
387         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
388         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
389         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
390         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
391         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
392 
393         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
394         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
395         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
396         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
397         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
398         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
399         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
400 
401         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
402         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
403         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
404         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
405         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
406         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
407         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
408 
409         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
410         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
411         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
412         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
413         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
414         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
415         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
416 
417         nz = bi[row+1] - diag_offset[row] - 1;
418         pv += 49;
419         for (j=0; j<nz; j++) {
420 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
421 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
422 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
423 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
424 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
425 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
426 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
427 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
428 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
429 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
430 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
431 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
432 	  x49 = pv[48];
433 	  x    = rtmp + 49*pj[j];
434 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
435 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
436 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
437 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
438 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
439 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
440 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
441 
442 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
443 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
444 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
445 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
446 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
447 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
448 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
449 
450 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
451 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
452 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
453 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
454 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
455 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
456 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
457 
458 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
459 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
460 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
461 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
462 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
463 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
464 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
465 
466 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
467 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
468 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
469 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
470 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
471 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
472 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
473 
474 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
475 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
476 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
477 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
478 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
479 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
480 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
481 
482 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
483 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
484 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
485 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
486 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
487 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
488 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
489           pv   += 49;
490         }
491         PLogFlops(686*nz+637);
492       }
493       row = *ajtmp++;
494     }
495     /* finished row so stick it into b->a */
496     pv = ba + 49*bi[i];
497     pj = bj + bi[i];
498     nz = bi[i+1] - bi[i];
499     for ( j=0; j<nz; j++ ) {
500       x      = rtmp+49*pj[j];
501       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
502       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
503       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
504       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
505       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
506       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
507       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
508       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
509       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
510       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
511       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
512       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
513       pv[48] = x[48];
514       pv   += 49;
515     }
516     /* invert diagonal block */
517     w = ba + 49*diag_offset[i];
518     ierr = Kernel_A_gets_inverse_A_7(w); CHKERRQ(ierr);
519   }
520 
521   PetscFree(rtmp);
522   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
523   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
524   C->factor = FACTOR_LU;
525   C->assembled = PETSC_TRUE;
526   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
527   PetscFunctionReturn(0);
528 }
529 
530 /*
531       Version for when blocks are 7 by 7 Using natural ordering
532 */
533 #undef __FUNC__
534 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering"
535 int MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering(Mat A,Mat *B)
536 {
537   Mat                C = *B;
538   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
539   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
540   int                *ajtmpold, *ajtmp, nz, row;
541   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
542   register int       *pj;
543   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
544   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
545   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
546   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
547   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
548   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
549   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
550   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
551   MatScalar          p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
552   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
553   MatScalar          x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
554   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
555   MatScalar          m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
556   MatScalar          *ba = b->a,*aa = a->a;
557 
558   PetscFunctionBegin;
559   rtmp  = (MatScalar *) PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
560   for ( i=0; i<n; i++ ) {
561     nz    = bi[i+1] - bi[i];
562     ajtmp = bj + bi[i];
563     for  ( j=0; j<nz; j++ ) {
564       x = rtmp+49*ajtmp[j];
565       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
566       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
567       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
568       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
569       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
570       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
571     }
572     /* load in initial (unfactored row) */
573     nz       = ai[i+1] - ai[i];
574     ajtmpold = aj + ai[i];
575     v        = aa + 49*ai[i];
576     for ( j=0; j<nz; j++ ) {
577       x    = rtmp+49*ajtmpold[j];
578       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
579       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
580       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
581       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
582       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
583       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
584       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
585       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
586       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
587       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
588       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
589       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
590       x[48] = v[48];
591       v    += 49;
592     }
593     row = *ajtmp++;
594     while (row < i) {
595       pc  = rtmp + 49*row;
596       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
597       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
598       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
599       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
600       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
601       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
602       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
603       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
604       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
605       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
606       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
607       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
608       p49 = pc[48];
609       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
610           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
611           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
612           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
613           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
614           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
615           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
616           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
617           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
618           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
619           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
620           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
621           p49 != 0.0) {
622         pv = ba + 49*diag_offset[row];
623         pj = bj + diag_offset[row] + 1;
624 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
625 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
626 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
627 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
628 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
629 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
630 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
631 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
632 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
633 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
634 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
635 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
636         x49 = pv[48];
637         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
638         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
639         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
640         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
641         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
642         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
643         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
644 
645         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
646         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
647         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
648         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
649         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
650         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
651         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
652 
653         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
654         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
655         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
656         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
657         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
658         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
659         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
660 
661         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
662         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
663         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
664         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
665         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
666         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
667         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
668 
669         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
670         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
671         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
672         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
673         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
674         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
675         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
676 
677         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
678         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
679         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
680         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
681         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
682         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
683         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
684 
685         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
686         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
687         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
688         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
689         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
690         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
691         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
692 
693         nz = bi[row+1] - diag_offset[row] - 1;
694         pv += 49;
695         for (j=0; j<nz; j++) {
696 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
697 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
698 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
699 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
700 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
701 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
702 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
703 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
704 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
705 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
706 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
707 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
708 	  x49 = pv[48];
709 	  x    = rtmp + 49*pj[j];
710 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
711 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
712 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
713 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
714 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
715 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
716 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
717 
718 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
719 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
720 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
721 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
722 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
723 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
724 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
725 
726 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
727 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
728 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
729 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
730 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
731 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
732 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
733 
734 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
735 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
736 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
737 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
738 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
739 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
740 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
741 
742 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
743 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
744 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
745 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
746 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
747 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
748 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
749 
750 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
751 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
752 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
753 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
754 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
755 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
756 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
757 
758 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
759 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
760 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
761 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
762 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
763 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
764 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
765           pv   += 49;
766         }
767         PLogFlops(686*nz+637);
768       }
769       row = *ajtmp++;
770     }
771     /* finished row so stick it into b->a */
772     pv = ba + 49*bi[i];
773     pj = bj + bi[i];
774     nz = bi[i+1] - bi[i];
775     for ( j=0; j<nz; j++ ) {
776       x      = rtmp+49*pj[j];
777       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
778       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
779       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
780       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
781       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
782       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
783       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
784       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
785       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
786       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
787       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
788       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
789       pv[48] = x[48];
790       pv   += 49;
791     }
792     /* invert diagonal block */
793     w = ba + 49*diag_offset[i];
794     ierr = Kernel_A_gets_inverse_A_7(w); CHKERRQ(ierr);
795   }
796 
797   PetscFree(rtmp);
798   C->factor    = FACTOR_LU;
799   C->assembled = PETSC_TRUE;
800   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
801   PetscFunctionReturn(0);
802 }
803 
804 /* ------------------------------------------------------------*/
805 /*
806       Version for when blocks are 6 by 6
807 */
808 #undef __FUNC__
809 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6"
810 int MatLUFactorNumeric_SeqBAIJ_6(Mat A,Mat *B)
811 {
812   Mat                C = *B;
813   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
814   IS                 isrow = b->row, isicol = b->icol;
815   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
816   int                *ajtmpold, *ajtmp, nz, row;
817   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
818   register int       *pj;
819   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
820   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
821   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
822   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
823   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
824   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
825   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
826   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
827   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
828   MatScalar          *ba = b->a,*aa = a->a;
829 
830   PetscFunctionBegin;
831   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
832   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
833   rtmp  = (MatScalar *) PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
834 
835   for ( i=0; i<n; i++ ) {
836     nz    = bi[i+1] - bi[i];
837     ajtmp = bj + bi[i];
838     for  ( j=0; j<nz; j++ ) {
839       x = rtmp+36*ajtmp[j];
840       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
841       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
842       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
843       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
844       x[34] = x[35] = 0.0 ;
845     }
846     /* load in initial (unfactored row) */
847     idx      = r[i];
848     nz       = ai[idx+1] - ai[idx];
849     ajtmpold = aj + ai[idx];
850     v        = aa + 36*ai[idx];
851     for ( j=0; j<nz; j++ ) {
852       x    = rtmp+36*ic[ajtmpold[j]];
853       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
854       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
855       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
856       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
857       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
858       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
859       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
860       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
861       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
862       v    += 36;
863     }
864     row = *ajtmp++;
865     while (row < i) {
866       pc  =  rtmp + 36*row;
867       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
868       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
869       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
870       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
871       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
872       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
873       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
874       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
875       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
876       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
877           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
878           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
879           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
880           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
881           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
882           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
883           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
884           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
885         pv = ba + 36*diag_offset[row];
886         pj = bj + diag_offset[row] + 1;
887 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
888 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
889 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
890 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
891 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
892 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
893 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
894 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
895 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
896         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
897         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
898         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
899         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
900         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
901         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
902 
903         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
904         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
905         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
906         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
907         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
908         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
909 
910         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
911         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
912         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
913         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
914         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
915         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
916 
917         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
918         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
919         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
920         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
921         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
922         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
923 
924         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
925         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
926         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
927         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
928         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
929         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
930 
931         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
932         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
933         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
934         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
935         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
936         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
937 
938         nz = bi[row+1] - diag_offset[row] - 1;
939         pv += 36;
940         for (j=0; j<nz; j++) {
941 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
942 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
943 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
944 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
945 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
946 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
947 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
948 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
949 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
950 	  x    = rtmp + 36*pj[j];
951           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
952           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
953           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
954           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
955           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
956           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
957 
958 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
959 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
960 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
961 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
962 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
963 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
964 
965 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
966 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
967 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
968 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
969 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
970 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
971 
972 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
973 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
974 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
975 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
976 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
977 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
978 
979 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
980 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
981 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
982 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
983 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
984 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
985 
986 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
987 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
988 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
989 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
990 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
991 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
992 
993           pv   += 36;
994         }
995         PLogFlops(432*nz+396);
996       }
997       row = *ajtmp++;
998     }
999     /* finished row so stick it into b->a */
1000     pv = ba + 36*bi[i];
1001     pj = bj + bi[i];
1002     nz = bi[i+1] - bi[i];
1003     for ( j=0; j<nz; j++ ) {
1004       x      = rtmp+36*pj[j];
1005       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1006       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1007       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1008       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1009       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1010       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1011       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1012       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1013       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1014       pv   += 36;
1015     }
1016     /* invert diagonal block */
1017     w = ba + 36*diag_offset[i];
1018     ierr = Kernel_A_gets_inverse_A_6(w); CHKERRQ(ierr);
1019   }
1020 
1021   PetscFree(rtmp);
1022   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
1023   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
1024   C->factor = FACTOR_LU;
1025   C->assembled = PETSC_TRUE;
1026   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1027   PetscFunctionReturn(0);
1028 }
1029 /*
1030       Version for when blocks are 6 by 6 Using natural ordering
1031 */
1032 #undef __FUNC__
1033 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering"
1034 int MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat A,Mat *B)
1035 {
1036   Mat                C = *B;
1037   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1038   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1039   int                *ajtmpold, *ajtmp, nz, row;
1040   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1041   register int       *pj;
1042   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1043   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1044   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1045   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1046   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1047   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1048   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1049   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
1050   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
1051   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
1052   MatScalar          *ba = b->a,*aa = a->a;
1053 
1054   PetscFunctionBegin;
1055   rtmp  = (MatScalar *) PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1056   for ( i=0; i<n; i++ ) {
1057     nz    = bi[i+1] - bi[i];
1058     ajtmp = bj + bi[i];
1059     for  ( j=0; j<nz; j++ ) {
1060       x = rtmp+36*ajtmp[j];
1061       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1062       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1063       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
1064       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
1065       x[34] = x[35] = 0.0 ;
1066     }
1067     /* load in initial (unfactored row) */
1068     nz       = ai[i+1] - ai[i];
1069     ajtmpold = aj + ai[i];
1070     v        = aa + 36*ai[i];
1071     for ( j=0; j<nz; j++ ) {
1072       x    = rtmp+36*ajtmpold[j];
1073       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
1074       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
1075       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
1076       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
1077       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
1078       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1079       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
1080       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
1081       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
1082       v    += 36;
1083     }
1084     row = *ajtmp++;
1085     while (row < i) {
1086       pc  = rtmp + 36*row;
1087       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1088       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
1089       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
1090       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
1091       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
1092       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1093       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
1094       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
1095       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
1096       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
1097           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
1098           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
1099           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
1100           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
1101           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
1102           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
1103           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
1104           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
1105         pv = ba + 36*diag_offset[row];
1106         pj = bj + diag_offset[row] + 1;
1107 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1108 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1109 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1110 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1111 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1112 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1113 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1114 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1115 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1116         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
1117         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
1118         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
1119         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
1120         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
1121         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
1122 
1123         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
1124         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
1125         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
1126         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
1127         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
1128         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
1129 
1130         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
1131         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
1132         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
1133         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
1134         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
1135         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
1136 
1137         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
1138         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
1139         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
1140         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
1141         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
1142         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
1143 
1144         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
1145         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
1146         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
1147         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
1148         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
1149         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
1150 
1151         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
1152         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
1153         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
1154         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
1155         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
1156         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
1157 
1158         nz = bi[row+1] - diag_offset[row] - 1;
1159         pv += 36;
1160         for (j=0; j<nz; j++) {
1161 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1162 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1163 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1164 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1165 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1166 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1167 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1168 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1169 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1170 	  x    = rtmp + 36*pj[j];
1171           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
1172           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
1173           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
1174           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
1175           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
1176           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
1177 
1178 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
1179 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
1180 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
1181 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
1182 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
1183 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
1184 
1185 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
1186 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
1187 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
1188 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
1189 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
1190 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
1191 
1192 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
1193 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
1194 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
1195 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
1196 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
1197 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
1198 
1199 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
1200 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
1201 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
1202 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
1203 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
1204 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
1205 
1206 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
1207 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
1208 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
1209 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
1210 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
1211 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
1212 
1213           pv   += 36;
1214         }
1215         PLogFlops(432*nz+396);
1216       }
1217       row = *ajtmp++;
1218     }
1219     /* finished row so stick it into b->a */
1220     pv = ba + 36*bi[i];
1221     pj = bj + bi[i];
1222     nz = bi[i+1] - bi[i];
1223     for ( j=0; j<nz; j++ ) {
1224       x      = rtmp+36*pj[j];
1225       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1226       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1227       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1228       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1229       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1230       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1231       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1232       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1233       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1234       pv   += 36;
1235     }
1236     /* invert diagonal block */
1237     w = ba + 36*diag_offset[i];
1238     ierr = Kernel_A_gets_inverse_A_6(w); CHKERRQ(ierr);
1239   }
1240 
1241   PetscFree(rtmp);
1242   C->factor    = FACTOR_LU;
1243   C->assembled = PETSC_TRUE;
1244   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1245   PetscFunctionReturn(0);
1246 }
1247 
1248 /* ------------------------------------------------------------*/
1249 /*
1250       Version for when blocks are 5 by 5
1251 */
1252 #undef __FUNC__
1253 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5"
1254 int MatLUFactorNumeric_SeqBAIJ_5(Mat A,Mat *B)
1255 {
1256   Mat                C = *B;
1257   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1258   IS                 isrow = b->row, isicol = b->icol;
1259   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1260   int                *ajtmpold, *ajtmp, nz, row;
1261   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
1262   register int       *pj;
1263   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1264   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1265   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1266   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
1267   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
1268   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1269   MatScalar          *ba = b->a,*aa = a->a;
1270 
1271   PetscFunctionBegin;
1272   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
1273   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
1274   rtmp  = (MatScalar *) PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1275 
1276   for ( i=0; i<n; i++ ) {
1277     nz    = bi[i+1] - bi[i];
1278     ajtmp = bj + bi[i];
1279     for  ( j=0; j<nz; j++ ) {
1280       x = rtmp+25*ajtmp[j];
1281       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1282       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1283       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1284     }
1285     /* load in initial (unfactored row) */
1286     idx      = r[i];
1287     nz       = ai[idx+1] - ai[idx];
1288     ajtmpold = aj + ai[idx];
1289     v        = aa + 25*ai[idx];
1290     for ( j=0; j<nz; j++ ) {
1291       x    = rtmp+25*ic[ajtmpold[j]];
1292       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1293       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1294       x[9] = v[9]; x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1295       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17];
1296       x[18] = v[18]; x[19] = v[19]; x[20] = v[20]; x[21] = v[21];
1297       x[22] = v[22]; x[23] = v[23]; x[24] = v[24];
1298       v    += 25;
1299     }
1300     row = *ajtmp++;
1301     while (row < i) {
1302       pc = rtmp + 25*row;
1303       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1304       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1305       p10 = pc[9]; p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1306       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17]; p19 = pc[18];
1307       p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1308       p25 = pc[24];
1309       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1310           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1311           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1312           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 ||
1313           p20 != 0.0 || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 ||
1314           p24 != 0.0 || p25 != 0.0) {
1315         pv = ba + 25*diag_offset[row];
1316         pj = bj + diag_offset[row] + 1;
1317         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1318         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1319         x10 = pv[9]; x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1320         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1321         x19 = pv[18]; x20 = pv[19]; x21 = pv[20]; x22 = pv[21];
1322         x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1323         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1324         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1325         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1326         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1327         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1328 
1329         pc[5] = m6 = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1330         pc[6] = m7 = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1331         pc[7] = m8 = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1332         pc[8] = m9 = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1333         pc[9] = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1334 
1335         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1336         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1337         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1338         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1339         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1340 
1341         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1342         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1343         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1344         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1345         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1346 
1347         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1348         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1349         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1350         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1351         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1352 
1353         nz = bi[row+1] - diag_offset[row] - 1;
1354         pv += 25;
1355         for (j=0; j<nz; j++) {
1356           x1   = pv[0];  x2 = pv[1];   x3  = pv[2];  x4  = pv[3];
1357           x5   = pv[4];  x6 = pv[5];   x7  = pv[6];  x8  = pv[7]; x9 = pv[8];
1358           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1359           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16];
1360           x18  = pv[17]; x19 = pv[18]; x20 = pv[19]; x21 = pv[20];
1361           x22  = pv[21]; x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1362           x    = rtmp + 25*pj[j];
1363           x[0] -= m1*x1 + m6*x2  + m11*x3 + m16*x4 + m21*x5;
1364           x[1] -= m2*x1 + m7*x2  + m12*x3 + m17*x4 + m22*x5;
1365           x[2] -= m3*x1 + m8*x2  + m13*x3 + m18*x4 + m23*x5;
1366           x[3] -= m4*x1 + m9*x2  + m14*x3 + m19*x4 + m24*x5;
1367           x[4] -= m5*x1 + m10*x2 + m15*x3 + m20*x4 + m25*x5;
1368 
1369           x[5] -= m1*x6 + m6*x7  + m11*x8 + m16*x9 + m21*x10;
1370           x[6] -= m2*x6 + m7*x7  + m12*x8 + m17*x9 + m22*x10;
1371           x[7] -= m3*x6 + m8*x7  + m13*x8 + m18*x9 + m23*x10;
1372           x[8] -= m4*x6 + m9*x7  + m14*x8 + m19*x9 + m24*x10;
1373           x[9] -= m5*x6 + m10*x7 + m15*x8 + m20*x9 + m25*x10;
1374 
1375           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1376           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1377           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1378           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1379           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1380 
1381           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1382           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1383           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1384           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1385           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1386 
1387           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1388           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1389           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1390           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1391           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1392 
1393           pv   += 25;
1394         }
1395         PLogFlops(250*nz+225);
1396       }
1397       row = *ajtmp++;
1398     }
1399     /* finished row so stick it into b->a */
1400     pv = ba + 25*bi[i];
1401     pj = bj + bi[i];
1402     nz = bi[i+1] - bi[i];
1403     for ( j=0; j<nz; j++ ) {
1404       x     = rtmp+25*pj[j];
1405       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1406       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1407       pv[9] = x[9]; pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1408       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16];
1409       pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20];
1410       pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23]; pv[24] = x[24];
1411       pv   += 25;
1412     }
1413     /* invert diagonal block */
1414     w = ba + 25*diag_offset[i];
1415     ierr = Kernel_A_gets_inverse_A_5(w); CHKERRQ(ierr);
1416   }
1417 
1418   PetscFree(rtmp);
1419   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
1420   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
1421   C->factor = FACTOR_LU;
1422   C->assembled = PETSC_TRUE;
1423   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1424   PetscFunctionReturn(0);
1425 }
1426 /*
1427       Version for when blocks are 5 by 5 Using natural ordering
1428 */
1429 #undef __FUNC__
1430 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering"
1431 int MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering(Mat A,Mat *B)
1432 {
1433   Mat                C = *B;
1434   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1435   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1436   int                *ajtmpold, *ajtmp, nz, row;
1437   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1438   register int       *pj;
1439   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1440   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1441   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1442   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1443   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1444   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1445   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1446   MatScalar          *ba = b->a,*aa = a->a;
1447 
1448   PetscFunctionBegin;
1449   rtmp  = (MatScalar *) PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1450   for ( i=0; i<n; i++ ) {
1451     nz    = bi[i+1] - bi[i];
1452     ajtmp = bj + bi[i];
1453     for  ( j=0; j<nz; j++ ) {
1454       x = rtmp+25*ajtmp[j];
1455       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1456       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1457       x[16] = x[17] = x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1458     }
1459     /* load in initial (unfactored row) */
1460     nz       = ai[i+1] - ai[i];
1461     ajtmpold = aj + ai[i];
1462     v        = aa + 25*ai[i];
1463     for ( j=0; j<nz; j++ ) {
1464       x    = rtmp+25*ajtmpold[j];
1465       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1466       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1467       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1468       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17]; x[18] = v[18];
1469       x[19] = v[19]; x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1470       x[24] = v[24];
1471       v    += 25;
1472     }
1473     row = *ajtmp++;
1474     while (row < i) {
1475       pc  = rtmp + 25*row;
1476       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1477       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1478       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1479       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17];
1480       p19 = pc[18]; p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22];
1481       p24 = pc[23]; p25 = pc[24];
1482       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1483           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1484           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1485           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0
1486           || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 || p25 != 0.0) {
1487         pv = ba + 25*diag_offset[row];
1488         pj = bj + diag_offset[row] + 1;
1489         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1490         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1491         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1492         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17]; x19 = pv[18];
1493         x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1494         x25 = pv[24];
1495         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1496         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1497         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1498         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1499         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1500 
1501         pc[5]  = m6  = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1502         pc[6]  = m7  = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1503         pc[7]  = m8  = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1504         pc[8]  = m9  = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1505         pc[9]  = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1506 
1507         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1508         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1509         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1510         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1511         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1512 
1513         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1514         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1515         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1516         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1517         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1518 
1519         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1520         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1521         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1522         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1523         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1524 
1525         nz = bi[row+1] - diag_offset[row] - 1;
1526         pv += 25;
1527         for (j=0; j<nz; j++) {
1528           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1529           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1530           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1531           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1532           x19 = pv[18];  x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22];
1533           x24 = pv[23];  x25 = pv[24];
1534           x    = rtmp + 25*pj[j];
1535           x[0] -= m1*x1 + m6*x2   + m11*x3  + m16*x4 + m21*x5;
1536           x[1] -= m2*x1 + m7*x2   + m12*x3  + m17*x4 + m22*x5;
1537           x[2] -= m3*x1 + m8*x2   + m13*x3  + m18*x4 + m23*x5;
1538           x[3] -= m4*x1 + m9*x2   + m14*x3  + m19*x4 + m24*x5;
1539           x[4] -= m5*x1 + m10*x2  + m15*x3  + m20*x4 + m25*x5;
1540 
1541           x[5] -= m1*x6 + m6*x7   + m11*x8  + m16*x9 + m21*x10;
1542           x[6] -= m2*x6 + m7*x7   + m12*x8  + m17*x9 + m22*x10;
1543           x[7] -= m3*x6 + m8*x7   + m13*x8  + m18*x9 + m23*x10;
1544           x[8] -= m4*x6 + m9*x7   + m14*x8  + m19*x9 + m24*x10;
1545           x[9] -= m5*x6 + m10*x7  + m15*x8  + m20*x9 + m25*x10;
1546 
1547           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1548           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1549           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1550           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1551           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1552 
1553           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1554           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1555           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1556           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1557           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1558 
1559           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1560           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1561           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1562           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1563           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1564           pv   += 25;
1565         }
1566         PLogFlops(250*nz+225);
1567       }
1568       row = *ajtmp++;
1569     }
1570     /* finished row so stick it into b->a */
1571     pv = ba + 25*bi[i];
1572     pj = bj + bi[i];
1573     nz = bi[i+1] - bi[i];
1574     for ( j=0; j<nz; j++ ) {
1575       x      = rtmp+25*pj[j];
1576       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1577       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1578       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1579       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16]; pv[17] = x[17];
1580       pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22];
1581       pv[23] = x[23]; pv[24] = x[24];
1582       pv   += 25;
1583     }
1584     /* invert diagonal block */
1585     w = ba + 25*diag_offset[i];
1586     ierr = Kernel_A_gets_inverse_A_5(w); CHKERRQ(ierr);
1587   }
1588 
1589   PetscFree(rtmp);
1590   C->factor    = FACTOR_LU;
1591   C->assembled = PETSC_TRUE;
1592   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1593   PetscFunctionReturn(0);
1594 }
1595 
1596 /* ------------------------------------------------------------*/
1597 /*
1598       Version for when blocks are 4 by 4
1599 */
1600 #undef __FUNC__
1601 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4"
1602 int MatLUFactorNumeric_SeqBAIJ_4(Mat A,Mat *B)
1603 {
1604   Mat                C = *B;
1605   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1606   IS                 isrow = b->row, isicol = b->icol;
1607   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1608   int                *ajtmpold, *ajtmp, nz, row;
1609   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
1610   register int       *pj;
1611   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1612   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1613   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1614   MatScalar          p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
1615   MatScalar          m13,m14,m15,m16;
1616   MatScalar          *ba = b->a,*aa = a->a;
1617 
1618   PetscFunctionBegin;
1619   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
1620   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
1621   rtmp  = (MatScalar *) PetscMalloc(16*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1622 
1623   for ( i=0; i<n; i++ ) {
1624     nz    = bi[i+1] - bi[i];
1625     ajtmp = bj + bi[i];
1626     for  ( j=0; j<nz; j++ ) {
1627       x = rtmp+16*ajtmp[j];
1628       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1629       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1630     }
1631     /* load in initial (unfactored row) */
1632     idx      = r[i];
1633     nz       = ai[idx+1] - ai[idx];
1634     ajtmpold = aj + ai[idx];
1635     v        = aa + 16*ai[idx];
1636     for ( j=0; j<nz; j++ ) {
1637       x    = rtmp+16*ic[ajtmpold[j]];
1638       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1639       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1640       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1641       x[14] = v[14]; x[15] = v[15];
1642       v    += 16;
1643     }
1644     row = *ajtmp++;
1645     while (row < i) {
1646       pc  = rtmp + 16*row;
1647       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1648       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1649       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1650       p15 = pc[14]; p16 = pc[15];
1651       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1652           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1653           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1654           || p16 != 0.0) {
1655         pv = ba + 16*diag_offset[row];
1656         pj = bj + diag_offset[row] + 1;
1657         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1658         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1659         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1660         x15 = pv[14]; x16 = pv[15];
1661         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
1662         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
1663         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
1664         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
1665 
1666         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
1667         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
1668         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
1669         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
1670 
1671         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
1672         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
1673         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
1674         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
1675 
1676         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
1677         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
1678         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
1679         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
1680 
1681         nz = bi[row+1] - diag_offset[row] - 1;
1682         pv += 16;
1683         for (j=0; j<nz; j++) {
1684           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1685           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1686           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1687           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
1688           x    = rtmp + 16*pj[j];
1689           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
1690           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
1691           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
1692           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
1693 
1694           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
1695           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
1696           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
1697           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
1698 
1699           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
1700           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
1701           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
1702           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
1703 
1704           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
1705           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
1706           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
1707           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
1708 
1709           pv   += 16;
1710         }
1711         PLogFlops(128*nz+112);
1712       }
1713       row = *ajtmp++;
1714     }
1715     /* finished row so stick it into b->a */
1716     pv = ba + 16*bi[i];
1717     pj = bj + bi[i];
1718     nz = bi[i+1] - bi[i];
1719     for ( j=0; j<nz; j++ ) {
1720       x      = rtmp+16*pj[j];
1721       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1722       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1723       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1724       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1725       pv   += 16;
1726     }
1727     /* invert diagonal block */
1728     w = ba + 16*diag_offset[i];
1729     ierr = Kernel_A_gets_inverse_A_4(w); CHKERRQ(ierr);
1730   }
1731 
1732   PetscFree(rtmp);
1733   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
1734   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
1735   C->factor = FACTOR_LU;
1736   C->assembled = PETSC_TRUE;
1737   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
1738   PetscFunctionReturn(0);
1739 }
1740 /*
1741       Version for when blocks are 4 by 4 Using natural ordering
1742 */
1743 #undef __FUNC__
1744 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering"
1745 int MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering(Mat A,Mat *B)
1746 {
1747   Mat                C = *B;
1748   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1749   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1750   int                *ajtmpold, *ajtmp, nz, row;
1751   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1752   register int       *pj;
1753   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1754   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1755   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1756   MatScalar          p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
1757   MatScalar          m13,m14,m15,m16;
1758   MatScalar          *ba = b->a,*aa = a->a;
1759 
1760   PetscFunctionBegin;
1761   rtmp  = (MatScalar *) PetscMalloc(16*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1762 
1763   for ( i=0; i<n; i++ ) {
1764     nz    = bi[i+1] - bi[i];
1765     ajtmp = bj + bi[i];
1766     for  ( j=0; j<nz; j++ ) {
1767       x = rtmp+16*ajtmp[j];
1768       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1769       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1770     }
1771     /* load in initial (unfactored row) */
1772     nz       = ai[i+1] - ai[i];
1773     ajtmpold = aj + ai[i];
1774     v        = aa + 16*ai[i];
1775     for ( j=0; j<nz; j++ ) {
1776       x    = rtmp+16*ajtmpold[j];
1777       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1778       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1779       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1780       x[14] = v[14]; x[15] = v[15];
1781       v    += 16;
1782     }
1783     row = *ajtmp++;
1784     while (row < i) {
1785       pc  = rtmp + 16*row;
1786       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1787       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1788       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1789       p15 = pc[14]; p16 = pc[15];
1790       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1791           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1792           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1793           || p16 != 0.0) {
1794         pv = ba + 16*diag_offset[row];
1795         pj = bj + diag_offset[row] + 1;
1796         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1797         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1798         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1799         x15 = pv[14]; x16 = pv[15];
1800         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
1801         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
1802         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
1803         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
1804 
1805         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
1806         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
1807         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
1808         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
1809 
1810         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
1811         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
1812         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
1813         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
1814 
1815         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
1816         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
1817         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
1818         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
1819 
1820         nz = bi[row+1] - diag_offset[row] - 1;
1821         pv += 16;
1822         for (j=0; j<nz; j++) {
1823           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1824           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1825           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1826           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
1827           x    = rtmp + 16*pj[j];
1828           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
1829           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
1830           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
1831           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
1832 
1833           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
1834           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
1835           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
1836           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
1837 
1838           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
1839           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
1840           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
1841           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
1842 
1843           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
1844           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
1845           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
1846           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
1847 
1848           pv   += 16;
1849         }
1850         PLogFlops(128*nz+112);
1851       }
1852       row = *ajtmp++;
1853     }
1854     /* finished row so stick it into b->a */
1855     pv = ba + 16*bi[i];
1856     pj = bj + bi[i];
1857     nz = bi[i+1] - bi[i];
1858     for ( j=0; j<nz; j++ ) {
1859       x      = rtmp+16*pj[j];
1860       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1861       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1862       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1863       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1864       pv   += 16;
1865     }
1866     /* invert diagonal block */
1867     w = ba + 16*diag_offset[i];
1868     ierr = Kernel_A_gets_inverse_A_4(w); CHKERRQ(ierr);
1869   }
1870 
1871   PetscFree(rtmp);
1872   C->factor    = FACTOR_LU;
1873   C->assembled = PETSC_TRUE;
1874   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
1875   PetscFunctionReturn(0);
1876 }
1877 
1878 
1879 /* ------------------------------------------------------------*/
1880 /*
1881       Version for when blocks are 3 by 3
1882 */
1883 #undef __FUNC__
1884 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3"
1885 int MatLUFactorNumeric_SeqBAIJ_3(Mat A,Mat *B)
1886 {
1887   Mat                C = *B;
1888   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1889   IS                 isrow = b->row, isicol = b->icol;
1890   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1891   int                *ajtmpold, *ajtmp, nz, row, *ai=a->i,*aj=a->j;
1892   int                *diag_offset = b->diag,idx;
1893   register int       *pj;
1894   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1895   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1896   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
1897   MatScalar          *ba = b->a,*aa = a->a;
1898 
1899   PetscFunctionBegin;
1900   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
1901   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
1902   rtmp  = (MatScalar *) PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1903 
1904   for ( i=0; i<n; i++ ) {
1905     nz    = bi[i+1] - bi[i];
1906     ajtmp = bj + bi[i];
1907     for  ( j=0; j<nz; j++ ) {
1908       x = rtmp + 9*ajtmp[j];
1909       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = 0.0;
1910     }
1911     /* load in initial (unfactored row) */
1912     idx      = r[i];
1913     nz       = ai[idx+1] - ai[idx];
1914     ajtmpold = aj + ai[idx];
1915     v        = aa + 9*ai[idx];
1916     for ( j=0; j<nz; j++ ) {
1917       x    = rtmp + 9*ic[ajtmpold[j]];
1918       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1919       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1920       v    += 9;
1921     }
1922     row = *ajtmp++;
1923     while (row < i) {
1924       pc = rtmp + 9*row;
1925       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1926       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1927       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1928           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
1929         pv = ba + 9*diag_offset[row];
1930         pj = bj + diag_offset[row] + 1;
1931         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1932         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1933         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
1934         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
1935         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
1936 
1937         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
1938         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
1939         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
1940 
1941         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
1942         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
1943         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
1944         nz = bi[row+1] - diag_offset[row] - 1;
1945         pv += 9;
1946         for (j=0; j<nz; j++) {
1947           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1948           x5   = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1949           x    = rtmp + 9*pj[j];
1950           x[0] -= m1*x1 + m4*x2 + m7*x3;
1951           x[1] -= m2*x1 + m5*x2 + m8*x3;
1952           x[2] -= m3*x1 + m6*x2 + m9*x3;
1953 
1954           x[3] -= m1*x4 + m4*x5 + m7*x6;
1955           x[4] -= m2*x4 + m5*x5 + m8*x6;
1956           x[5] -= m3*x4 + m6*x5 + m9*x6;
1957 
1958           x[6] -= m1*x7 + m4*x8 + m7*x9;
1959           x[7] -= m2*x7 + m5*x8 + m8*x9;
1960           x[8] -= m3*x7 + m6*x8 + m9*x9;
1961           pv   += 9;
1962         }
1963         PLogFlops(54*nz+36);
1964       }
1965       row = *ajtmp++;
1966     }
1967     /* finished row so stick it into b->a */
1968     pv = ba + 9*bi[i];
1969     pj = bj + bi[i];
1970     nz = bi[i+1] - bi[i];
1971     for ( j=0; j<nz; j++ ) {
1972       x     = rtmp + 9*pj[j];
1973       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1974       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1975       pv   += 9;
1976     }
1977     /* invert diagonal block */
1978     w = ba + 9*diag_offset[i];
1979     ierr = Kernel_A_gets_inverse_A_3(w); CHKERRQ(ierr);
1980   }
1981 
1982   PetscFree(rtmp);
1983   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
1984   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
1985   C->factor = FACTOR_LU;
1986   C->assembled = PETSC_TRUE;
1987   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
1988   PetscFunctionReturn(0);
1989 }
1990 /*
1991       Version for when blocks are 3 by 3 Using natural ordering
1992 */
1993 #undef __FUNC__
1994 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering"
1995 int MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering(Mat A,Mat *B)
1996 {
1997   Mat                C = *B;
1998   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1999   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2000   int                *ajtmpold, *ajtmp, nz, row;
2001   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
2002   register int       *pj;
2003   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
2004   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
2005   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
2006   MatScalar          *ba = b->a,*aa = a->a;
2007 
2008   PetscFunctionBegin;
2009   rtmp  = (MatScalar *) PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2010 
2011   for ( i=0; i<n; i++ ) {
2012     nz    = bi[i+1] - bi[i];
2013     ajtmp = bj + bi[i];
2014     for  ( j=0; j<nz; j++ ) {
2015       x = rtmp+9*ajtmp[j];
2016       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = 0.0;
2017     }
2018     /* load in initial (unfactored row) */
2019     nz       = ai[i+1] - ai[i];
2020     ajtmpold = aj + ai[i];
2021     v        = aa + 9*ai[i];
2022     for ( j=0; j<nz; j++ ) {
2023       x    = rtmp+9*ajtmpold[j];
2024       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2025       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
2026       v    += 9;
2027     }
2028     row = *ajtmp++;
2029     while (row < i) {
2030       pc  = rtmp + 9*row;
2031       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2032       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
2033       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
2034           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
2035         pv = ba + 9*diag_offset[row];
2036         pj = bj + diag_offset[row] + 1;
2037         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2038         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
2039         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
2040         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
2041         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
2042 
2043         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
2044         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
2045         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
2046 
2047         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
2048         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
2049         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
2050 
2051         nz = bi[row+1] - diag_offset[row] - 1;
2052         pv += 9;
2053         for (j=0; j<nz; j++) {
2054           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2055           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
2056           x    = rtmp + 9*pj[j];
2057           x[0] -= m1*x1 + m4*x2 + m7*x3;
2058           x[1] -= m2*x1 + m5*x2 + m8*x3;
2059           x[2] -= m3*x1 + m6*x2 + m9*x3;
2060 
2061           x[3] -= m1*x4 + m4*x5 + m7*x6;
2062           x[4] -= m2*x4 + m5*x5 + m8*x6;
2063           x[5] -= m3*x4 + m6*x5 + m9*x6;
2064 
2065           x[6] -= m1*x7 + m4*x8 + m7*x9;
2066           x[7] -= m2*x7 + m5*x8 + m8*x9;
2067           x[8] -= m3*x7 + m6*x8 + m9*x9;
2068           pv   += 9;
2069         }
2070         PLogFlops(54*nz+36);
2071       }
2072       row = *ajtmp++;
2073     }
2074     /* finished row so stick it into b->a */
2075     pv = ba + 9*bi[i];
2076     pj = bj + bi[i];
2077     nz = bi[i+1] - bi[i];
2078     for ( j=0; j<nz; j++ ) {
2079       x      = rtmp+9*pj[j];
2080       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2081       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
2082       pv   += 9;
2083     }
2084     /* invert diagonal block */
2085     w = ba + 9*diag_offset[i];
2086     ierr = Kernel_A_gets_inverse_A_3(w); CHKERRQ(ierr);
2087   }
2088 
2089   PetscFree(rtmp);
2090   C->factor    = FACTOR_LU;
2091   C->assembled = PETSC_TRUE;
2092   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
2093   PetscFunctionReturn(0);
2094 }
2095 
2096 /* ------------------------------------------------------------*/
2097 /*
2098       Version for when blocks are 2 by 2
2099 */
2100 #undef __FUNC__
2101 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2"
2102 int MatLUFactorNumeric_SeqBAIJ_2(Mat A,Mat *B)
2103 {
2104   Mat                C = *B;
2105   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
2106   IS                 isrow = b->row, isicol = b->icol;
2107   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2108   int                *ajtmpold, *ajtmp, nz, row;
2109   int                *diag_offset=b->diag,idx,*ai=a->i,*aj=a->j;
2110   register int       *pj;
2111   register MatScalar *pv,*v,*rtmp,m1,m2,m3,m4,*pc,*w,*x,x1,x2,x3,x4;
2112   MatScalar          p1,p2,p3,p4;
2113   MatScalar          *ba = b->a,*aa = a->a;
2114 
2115   PetscFunctionBegin;
2116   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
2117   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
2118   rtmp  = (MatScalar *) PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2119 
2120   for ( i=0; i<n; i++ ) {
2121     nz    = bi[i+1] - bi[i];
2122     ajtmp = bj + bi[i];
2123     for  ( j=0; j<nz; j++ ) {
2124       x = rtmp+4*ajtmp[j]; x[0] = x[1] = x[2] = x[3] = 0.0;
2125     }
2126     /* load in initial (unfactored row) */
2127     idx      = r[i];
2128     nz       = ai[idx+1] - ai[idx];
2129     ajtmpold = aj + ai[idx];
2130     v        = aa + 4*ai[idx];
2131     for ( j=0; j<nz; j++ ) {
2132       x    = rtmp+4*ic[ajtmpold[j]];
2133       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
2134       v    += 4;
2135     }
2136     row = *ajtmp++;
2137     while (row < i) {
2138       pc = rtmp + 4*row;
2139       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
2140       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2141         pv = ba + 4*diag_offset[row];
2142         pj = bj + diag_offset[row] + 1;
2143         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2144         pc[0] = m1 = p1*x1 + p3*x2;
2145         pc[1] = m2 = p2*x1 + p4*x2;
2146         pc[2] = m3 = p1*x3 + p3*x4;
2147         pc[3] = m4 = p2*x3 + p4*x4;
2148         nz = bi[row+1] - diag_offset[row] - 1;
2149         pv += 4;
2150         for (j=0; j<nz; j++) {
2151           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2152           x    = rtmp + 4*pj[j];
2153           x[0] -= m1*x1 + m3*x2;
2154           x[1] -= m2*x1 + m4*x2;
2155           x[2] -= m1*x3 + m3*x4;
2156           x[3] -= m2*x3 + m4*x4;
2157           pv   += 4;
2158         }
2159         PLogFlops(16*nz+12);
2160       }
2161       row = *ajtmp++;
2162     }
2163     /* finished row so stick it into b->a */
2164     pv = ba + 4*bi[i];
2165     pj = bj + bi[i];
2166     nz = bi[i+1] - bi[i];
2167     for ( j=0; j<nz; j++ ) {
2168       x     = rtmp+4*pj[j];
2169       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
2170       pv   += 4;
2171     }
2172     /* invert diagonal block */
2173     w = ba + 4*diag_offset[i];
2174     ierr = Kernel_A_gets_inverse_A_2(w); CHKERRQ(ierr);
2175     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2176   }
2177 
2178   PetscFree(rtmp);
2179   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
2180   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
2181   C->factor = FACTOR_LU;
2182   C->assembled = PETSC_TRUE;
2183   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2184   PetscFunctionReturn(0);
2185 }
2186 /*
2187       Version for when blocks are 2 by 2 Using natural ordering
2188 */
2189 #undef __FUNC__
2190 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering"
2191 int MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering(Mat A,Mat *B)
2192 {
2193   Mat                C = *B;
2194   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
2195   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2196   int                *ajtmpold, *ajtmp, nz, row;
2197   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
2198   register int       *pj;
2199   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
2200   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,x1,x2,x3,x4;
2201   MatScalar          *ba = b->a,*aa = a->a;
2202 
2203   PetscFunctionBegin;
2204   rtmp  = (MatScalar *) PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2205 
2206   for ( i=0; i<n; i++ ) {
2207     nz    = bi[i+1] - bi[i];
2208     ajtmp = bj + bi[i];
2209     for  ( j=0; j<nz; j++ ) {
2210       x = rtmp+4*ajtmp[j];
2211       x[0]  = x[1]  = x[2]  = x[3]  = 0.0;
2212     }
2213     /* load in initial (unfactored row) */
2214     nz       = ai[i+1] - ai[i];
2215     ajtmpold = aj + ai[i];
2216     v        = aa + 4*ai[i];
2217     for ( j=0; j<nz; j++ ) {
2218       x    = rtmp+4*ajtmpold[j];
2219       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2220       v    += 4;
2221     }
2222     row = *ajtmp++;
2223     while (row < i) {
2224       pc  = rtmp + 4*row;
2225       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2226       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2227         pv = ba + 4*diag_offset[row];
2228         pj = bj + diag_offset[row] + 1;
2229         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2230         pc[0] = m1 = p1*x1 + p3*x2;
2231         pc[1] = m2 = p2*x1 + p4*x2;
2232         pc[2] = m3 = p1*x3 + p3*x4;
2233         pc[3] = m4 = p2*x3 + p4*x4;
2234         nz = bi[row+1] - diag_offset[row] - 1;
2235         pv += 4;
2236         for (j=0; j<nz; j++) {
2237           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2238           x    = rtmp + 4*pj[j];
2239           x[0] -= m1*x1 + m3*x2;
2240           x[1] -= m2*x1 + m4*x2;
2241           x[2] -= m1*x3 + m3*x4;
2242           x[3] -= m2*x3 + m4*x4;
2243           pv   += 4;
2244         }
2245         PLogFlops(16*nz+12);
2246       }
2247       row = *ajtmp++;
2248     }
2249     /* finished row so stick it into b->a */
2250     pv = ba + 4*bi[i];
2251     pj = bj + bi[i];
2252     nz = bi[i+1] - bi[i];
2253     for ( j=0; j<nz; j++ ) {
2254       x      = rtmp+4*pj[j];
2255       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2256       pv   += 4;
2257     }
2258     /* invert diagonal block */
2259     w = ba + 4*diag_offset[i];
2260     ierr = Kernel_A_gets_inverse_A_2(w); CHKERRQ(ierr);
2261     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2262   }
2263 
2264   PetscFree(rtmp);
2265   C->factor    = FACTOR_LU;
2266   C->assembled = PETSC_TRUE;
2267   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2268   PetscFunctionReturn(0);
2269 }
2270 
2271 /* ----------------------------------------------------------- */
2272 /*
2273      Version for when blocks are 1 by 1.
2274 */
2275 #undef __FUNC__
2276 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_1"
2277 int MatLUFactorNumeric_SeqBAIJ_1(Mat A,Mat *B)
2278 {
2279   Mat                C = *B;
2280   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data, *b = (Mat_SeqBAIJ *)C->data;
2281   IS                 isrow = b->row, isicol = b->icol;
2282   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2283   int                *ajtmpold, *ajtmp, nz, row,*ai = a->i,*aj = a->j;
2284   int                *diag_offset = b->diag,diag;
2285   register int       *pj;
2286   register MatScalar *pv,*v,*rtmp,multiplier,*pc;
2287   MatScalar          *ba = b->a,*aa = a->a;
2288 
2289   PetscFunctionBegin;
2290   ierr  = ISGetIndices(isrow,&r); CHKERRQ(ierr);
2291   ierr  = ISGetIndices(isicol,&ic); CHKERRQ(ierr);
2292   rtmp  = (MatScalar *) PetscMalloc((n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2293 
2294   for ( i=0; i<n; i++ ) {
2295     nz    = bi[i+1] - bi[i];
2296     ajtmp = bj + bi[i];
2297     for  ( j=0; j<nz; j++ ) rtmp[ajtmp[j]] = 0.0;
2298 
2299     /* load in initial (unfactored row) */
2300     nz       = ai[r[i]+1] - ai[r[i]];
2301     ajtmpold = aj + ai[r[i]];
2302     v        = aa + ai[r[i]];
2303     for ( j=0; j<nz; j++ ) rtmp[ic[ajtmpold[j]]] =  v[j];
2304 
2305     row = *ajtmp++;
2306     while (row < i) {
2307       pc = rtmp + row;
2308       if (*pc != 0.0) {
2309         pv         = ba + diag_offset[row];
2310         pj         = bj + diag_offset[row] + 1;
2311         multiplier = *pc * *pv++;
2312         *pc        = multiplier;
2313         nz         = bi[row+1] - diag_offset[row] - 1;
2314         for (j=0; j<nz; j++) rtmp[pj[j]] -= multiplier * pv[j];
2315         PLogFlops(1+2*nz);
2316       }
2317       row = *ajtmp++;
2318     }
2319     /* finished row so stick it into b->a */
2320     pv = ba + bi[i];
2321     pj = bj + bi[i];
2322     nz = bi[i+1] - bi[i];
2323     for ( j=0; j<nz; j++ ) {pv[j] = rtmp[pj[j]];}
2324     diag = diag_offset[i] - bi[i];
2325     /* check pivot entry for current row */
2326     if (pv[diag] == 0.0) {
2327       SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,0,"Zero pivot");
2328     }
2329     pv[diag] = 1.0/pv[diag];
2330   }
2331 
2332   PetscFree(rtmp);
2333   ierr = ISRestoreIndices(isicol,&ic); CHKERRQ(ierr);
2334   ierr = ISRestoreIndices(isrow,&r); CHKERRQ(ierr);
2335   C->factor    = FACTOR_LU;
2336   C->assembled = PETSC_TRUE;
2337   PLogFlops(b->n);
2338   PetscFunctionReturn(0);
2339 }
2340 
2341 /* ----------------------------------------------------------- */
2342 #undef __FUNC__
2343 #define __FUNC__ "MatLUFactor_SeqBAIJ"
2344 int MatLUFactor_SeqBAIJ(Mat A,IS row,IS col,double f)
2345 {
2346   Mat_SeqBAIJ    *mat = (Mat_SeqBAIJ *) A->data;
2347   int            ierr;
2348   Mat            C;
2349   PetscOps *Abops;
2350   MatOps   Aops;
2351 
2352   PetscFunctionBegin;
2353   ierr = MatLUFactorSymbolic(A,row,col,f,&C); CHKERRQ(ierr);
2354   ierr = MatLUFactorNumeric(A,&C); CHKERRQ(ierr);
2355 
2356   /* free all the data structures from mat */
2357   PetscFree(mat->a);
2358   if (!mat->singlemalloc) {PetscFree(mat->i); PetscFree(mat->j);}
2359   if (mat->diag) PetscFree(mat->diag);
2360   if (mat->ilen) PetscFree(mat->ilen);
2361   if (mat->imax) PetscFree(mat->imax);
2362   if (mat->solve_work) PetscFree(mat->solve_work);
2363   if (mat->mult_work) PetscFree(mat->mult_work);
2364   if (mat->icol) {ierr = ISDestroy(mat->icol);CHKERRQ(ierr);}
2365   PetscFree(mat);
2366 
2367   ierr = MapDestroy(A->rmap);CHKERRQ(ierr);
2368   ierr = MapDestroy(A->cmap);CHKERRQ(ierr);
2369 
2370   /*
2371        This is horrible, horrible code. We need to keep the
2372     A pointers for the bops and ops but copy everything
2373     else from C.
2374   */
2375   Abops    = A->bops;
2376   Aops     = A->ops;
2377   PetscMemcpy(A,C,sizeof(struct _p_Mat));
2378   mat = (Mat_SeqBAIJ *) A->data;
2379   PLogObjectParent(A,mat->icol);
2380 
2381   A->bops  = Abops;
2382   A->ops   = Aops;
2383   A->qlist = 0;
2384 
2385   PetscHeaderDestroy(C);
2386   PetscFunctionReturn(0);
2387 }
2388 
2389 
2390 
2391