xref: /petsc/src/mat/impls/baij/seq/baijfact.c (revision ac2a4f0d24b3b6a4ee93edbcad41f4bb9e923944)
1 /*$Id: baijfact.c,v 1.73 1999/06/30 23:51:46 balay Exp bsmith $*/
2 /*
3     Factorization code for BAIJ format.
4 */
5 #include "src/mat/impls/baij/seq/baij.h"
6 #include "src/vec/vecimpl.h"
7 #include "src/inline/ilu.h"
8 
9 /*
10     The symbolic factorization code is identical to that for AIJ format,
11   except for very small changes since this is now a SeqBAIJ datastructure.
12   NOT good code reuse.
13 */
14 #undef __FUNC__
15 #define __FUNC__ "MatLUFactorSymbolic_SeqBAIJ"
16 int MatLUFactorSymbolic_SeqBAIJ(Mat A,IS isrow,IS iscol,double f,Mat *B)
17 {
18   Mat_SeqBAIJ *a = (Mat_SeqBAIJ *) A->data, *b;
19   IS          isicol;
20   int         *r,*ic, ierr, i, n = a->mbs, *ai = a->i, *aj = a->j;
21   int         *ainew,*ajnew, jmax,*fill, *ajtmp, nz, bs = a->bs, bs2=a->bs2;
22   int         *idnew, idx, row,m,fm, nnz, nzi,realloc = 0,nzbd,*im;
23 
24   PetscFunctionBegin;
25   PetscValidHeaderSpecific(isrow,IS_COOKIE);
26   PetscValidHeaderSpecific(iscol,IS_COOKIE);
27   ierr = ISInvertPermutation(iscol,&isicol);CHKERRQ(ierr);
28   ISGetIndices(isrow,&r); ISGetIndices(isicol,&ic);
29 
30   /* get new row pointers */
31   ainew = (int *) PetscMalloc( (n+1)*sizeof(int) );CHKPTRQ(ainew);
32   ainew[0] = 0;
33   /* don't know how many column pointers are needed so estimate */
34   jmax = (int) (f*ai[n] + 1);
35   ajnew = (int *) PetscMalloc( (jmax)*sizeof(int) );CHKPTRQ(ajnew);
36   /* fill is a linked list of nonzeros in active row */
37   fill = (int *) PetscMalloc( (2*n+1)*sizeof(int));CHKPTRQ(fill);
38   im = fill + n + 1;
39   /* idnew is location of diagonal in factor */
40   idnew = (int *) PetscMalloc( (n+1)*sizeof(int));CHKPTRQ(idnew);
41   idnew[0] = 0;
42 
43   for ( i=0; i<n; i++ ) {
44     /* first copy previous fill into linked list */
45     nnz     = nz    = ai[r[i]+1] - ai[r[i]];
46     if (!nz) SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,1,"Empty row in matrix");
47     ajtmp   = aj + ai[r[i]];
48     fill[n] = n;
49     while (nz--) {
50       fm  = n;
51       idx = ic[*ajtmp++];
52       do {
53         m  = fm;
54         fm = fill[m];
55       } while (fm < idx);
56       fill[m]   = idx;
57       fill[idx] = fm;
58     }
59     row = fill[n];
60     while ( row < i ) {
61       ajtmp = ajnew + idnew[row] + 1;
62       nzbd  = 1 + idnew[row] - ainew[row];
63       nz    = im[row] - nzbd;
64       fm    = row;
65       while (nz-- > 0) {
66         idx = *ajtmp++;
67         nzbd++;
68         if (idx == i) im[row] = nzbd;
69         do {
70           m  = fm;
71           fm = fill[m];
72         } while (fm < idx);
73         if (fm != idx) {
74           fill[m]   = idx;
75           fill[idx] = fm;
76           fm        = idx;
77           nnz++;
78         }
79       }
80       row = fill[row];
81     }
82     /* copy new filled row into permanent storage */
83     ainew[i+1] = ainew[i] + nnz;
84     if (ainew[i+1] > jmax) {
85 
86       /* estimate how much additional space we will need */
87       /* use the strategy suggested by David Hysom <hysom@perch-t.icase.edu> */
88       /* just double the memory each time */
89       int maxadd = jmax;
90       /* maxadd = (int) ((f*(ai[n]+1)*(n-i+5))/n); */
91       if (maxadd < nnz) maxadd = (n-i)*(nnz+1);
92       jmax += maxadd;
93 
94       /* allocate a longer ajnew */
95       ajtmp = (int *) PetscMalloc( jmax*sizeof(int) );CHKPTRQ(ajtmp);
96       ierr  = PetscMemcpy(ajtmp,ajnew,ainew[i]*sizeof(int));CHKERRQ(ierr);
97       ierr = PetscFree(ajnew);CHKERRQ(ierr);
98       ajnew = ajtmp;
99       realloc++; /* count how many times we realloc */
100     }
101     ajtmp = ajnew + ainew[i];
102     fm    = fill[n];
103     nzi   = 0;
104     im[i] = nnz;
105     while (nnz--) {
106       if (fm < i) nzi++;
107       *ajtmp++ = fm;
108       fm       = fill[fm];
109     }
110     idnew[i] = ainew[i] + nzi;
111   }
112 
113   if (ai[n] != 0) {
114     double af = ((double)ainew[n])/((double)ai[n]);
115     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Reallocs %d Fill ratio:given %g needed %g\n",
116              realloc,f,af);
117     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Run with -pc_lu_fill %g or use \n",af);
118     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:PCLUSetFill(pc,%g);\n",af);
119     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:for best performance.\n");
120   } else {
121      PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Empty matrix.\n");
122   }
123 
124   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
125   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
126 
127   ierr = PetscFree(fill);CHKERRQ(ierr);
128 
129   /* put together the new matrix */
130   ierr = MatCreateSeqBAIJ(A->comm,bs,bs*n,bs*n,0,PETSC_NULL,B);CHKERRQ(ierr);
131   PLogObjectParent(*B,isicol);
132   b = (Mat_SeqBAIJ *) (*B)->data;
133   ierr = PetscFree(b->imax);CHKERRQ(ierr);
134   b->singlemalloc = 0;
135   /* the next line frees the default space generated by the Create() */
136   ierr = PetscFree(b->a);CHKERRQ(ierr);
137   ierr = PetscFree(b->ilen);CHKERRQ(ierr);
138   b->a          = (MatScalar *) PetscMalloc((ainew[n]+1)*sizeof(MatScalar)*bs2);CHKPTRQ(b->a);
139   b->j          = ajnew;
140   b->i          = ainew;
141   b->diag       = idnew;
142   b->ilen       = 0;
143   b->imax       = 0;
144   b->row        = isrow;
145   b->col        = iscol;
146   b->icol       = isicol;
147   b->solve_work = (Scalar *) PetscMalloc( (bs*n+bs)*sizeof(Scalar));CHKPTRQ(b->solve_work);
148   /* In b structure:  Free imax, ilen, old a, old j.
149      Allocate idnew, solve_work, new a, new j */
150   PLogObjectMemory(*B,(ainew[n]-n)*(sizeof(int)+sizeof(MatScalar)));
151   b->maxnz = b->nz = ainew[n];
152 
153   (*B)->factor                 = FACTOR_LU;
154   (*B)->info.factor_mallocs    = realloc;
155   (*B)->info.fill_ratio_given  = f;
156   if (ai[n] != 0) {
157     (*B)->info.fill_ratio_needed = ((double)ainew[n])/((double)ai[n]);
158   } else {
159     (*B)->info.fill_ratio_needed = 0.0;
160   }
161 
162 
163   PetscFunctionReturn(0);
164 }
165 
166 /* ----------------------------------------------------------- */
167 #undef __FUNC__
168 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_N"
169 int MatLUFactorNumeric_SeqBAIJ_N(Mat A,Mat *B)
170 {
171   Mat                C = *B;
172   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
173   IS                 isrow = b->row, isicol = b->icol;
174   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
175   int                *ajtmpold, *ajtmp, nz, row, bslog,*ai=a->i,*aj=a->j,k,flg;
176   int                *diag_offset=b->diag,diag,bs=a->bs,bs2 = a->bs2,*v_pivots;
177   register int       *pj;
178   register MatScalar *pv,*v,*rtmp,*multiplier,*v_work,*pc,*w;
179   MatScalar          *ba = b->a,*aa = a->a;
180 
181   PetscFunctionBegin;
182   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
183   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
184   rtmp = (MatScalar *) PetscMalloc(bs2*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
185   ierr = PetscMemzero(rtmp,bs2*(n+1)*sizeof(MatScalar));CHKERRQ(ierr);
186   /* generate work space needed by dense LU factorization */
187   v_work     = (MatScalar *) PetscMalloc(bs*sizeof(int) + (bs+bs2)*sizeof(MatScalar));CHKPTRQ(v_work);
188   multiplier = v_work + bs;
189   v_pivots   = (int *) (multiplier + bs2);
190 
191   /* flops in while loop */
192   bslog = 2*bs*bs2;
193 
194   for ( i=0; i<n; i++ ) {
195     nz    = bi[i+1] - bi[i];
196     ajtmp = bj + bi[i];
197     for  ( j=0; j<nz; j++ ) {
198       ierr = PetscMemzero(rtmp+bs2*ajtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
199     }
200     /* load in initial (unfactored row) */
201     nz       = ai[r[i]+1] - ai[r[i]];
202     ajtmpold = aj + ai[r[i]];
203     v        = aa + bs2*ai[r[i]];
204     for ( j=0; j<nz; j++ ) {
205       ierr = PetscMemcpy(rtmp+bs2*ic[ajtmpold[j]],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
206     }
207     row = *ajtmp++;
208     while (row < i) {
209       pc = rtmp + bs2*row;
210 /*      if (*pc) { */
211       for ( flg=0,k=0; k<bs2; k++ ) { if (pc[k]!=0.0) { flg =1; break; }}
212       if (flg) {
213         pv = ba + bs2*diag_offset[row];
214         pj = bj + diag_offset[row] + 1;
215         Kernel_A_gets_A_times_B(bs,pc,pv,multiplier);
216         nz = bi[row+1] - diag_offset[row] - 1;
217         pv += bs2;
218         for (j=0; j<nz; j++) {
219           Kernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j);
220         }
221         PLogFlops(bslog*(nz+1)-bs);
222       }
223         row = *ajtmp++;
224     }
225     /* finished row so stick it into b->a */
226     pv = ba + bs2*bi[i];
227     pj = bj + bi[i];
228     nz = bi[i+1] - bi[i];
229     for ( j=0; j<nz; j++ ) {
230       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
231     }
232     diag = diag_offset[i] - bi[i];
233     /* invert diagonal block */
234     w = pv + bs2*diag;
235     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
236   }
237 
238   ierr = PetscFree(rtmp);CHKERRQ(ierr);
239   ierr = PetscFree(v_work);CHKERRQ(ierr);
240   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
241   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
242   C->factor = FACTOR_LU;
243   C->assembled = PETSC_TRUE;
244   PLogFlops(1.3333*bs*bs2*b->mbs); /* from inverting diagonal blocks */
245   PetscFunctionReturn(0);
246 }
247 /* ------------------------------------------------------------*/
248 /*
249       Version for when blocks are 7 by 7
250 */
251 #undef __FUNC__
252 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7"
253 int MatLUFactorNumeric_SeqBAIJ_7(Mat A,Mat *B)
254 {
255   Mat                C = *B;
256   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
257   IS                 isrow = b->row, isicol = b->icol;
258   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
259   int                *ajtmpold, *ajtmp, nz, row;
260   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
261   register int       *pj;
262   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
263   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
264   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
265   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
266   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
267   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
268   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
269   MatScalar          p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
270   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
271   MatScalar          x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
272   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
273   MatScalar          m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
274   MatScalar          *ba = b->a,*aa = a->a;
275 
276   PetscFunctionBegin;
277   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
278   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
279   rtmp  = (MatScalar *) PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
280 
281   for ( i=0; i<n; i++ ) {
282     nz    = bi[i+1] - bi[i];
283     ajtmp = bj + bi[i];
284     for  ( j=0; j<nz; j++ ) {
285       x = rtmp+49*ajtmp[j];
286       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
287       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
288       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
289       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
290       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
291       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
292     }
293     /* load in initial (unfactored row) */
294     idx      = r[i];
295     nz       = ai[idx+1] - ai[idx];
296     ajtmpold = aj + ai[idx];
297     v        = aa + 49*ai[idx];
298     for ( j=0; j<nz; j++ ) {
299       x    = rtmp+49*ic[ajtmpold[j]];
300       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
301       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
302       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
303       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
304       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
305       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
306       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
307       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
308       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
309       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
310       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
311       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
312       x[48] = v[48];
313       v    += 49;
314     }
315     row = *ajtmp++;
316     while (row < i) {
317       pc  =  rtmp + 49*row;
318       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
319       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
320       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
321       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
322       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
323       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
324       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
325       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
326       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
327       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
328       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
329       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
330       p49 = pc[48];
331       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
332           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
333           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
334           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
335           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
336           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
337           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
338           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
339           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
340           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
341           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
342           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
343           p49 != 0.0) {
344         pv = ba + 49*diag_offset[row];
345         pj = bj + diag_offset[row] + 1;
346 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
347 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
348 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
349 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
350 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
351 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
352 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
353 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
354 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
355 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
356 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
357 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
358 	x49 = pv[48];
359         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
360         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
361         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
362         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
363         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
364         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
365         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
366 
367         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
368         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
369         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
370         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
371         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
372         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
373         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
374 
375         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
376         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
377         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
378         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
379         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
380         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
381         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
382 
383         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
384         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
385         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
386         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
387         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
388         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
389         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
390 
391         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
392         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
393         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
394         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
395         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
396         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
397         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
398 
399         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
400         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
401         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
402         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
403         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
404         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
405         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
406 
407         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
408         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
409         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
410         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
411         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
412         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
413         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
414 
415         nz = bi[row+1] - diag_offset[row] - 1;
416         pv += 49;
417         for (j=0; j<nz; j++) {
418 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
419 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
420 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
421 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
422 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
423 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
424 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
425 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
426 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
427 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
428 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
429 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
430 	  x49 = pv[48];
431 	  x    = rtmp + 49*pj[j];
432 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
433 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
434 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
435 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
436 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
437 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
438 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
439 
440 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
441 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
442 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
443 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
444 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
445 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
446 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
447 
448 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
449 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
450 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
451 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
452 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
453 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
454 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
455 
456 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
457 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
458 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
459 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
460 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
461 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
462 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
463 
464 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
465 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
466 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
467 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
468 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
469 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
470 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
471 
472 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
473 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
474 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
475 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
476 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
477 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
478 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
479 
480 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
481 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
482 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
483 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
484 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
485 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
486 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
487           pv   += 49;
488         }
489         PLogFlops(686*nz+637);
490       }
491       row = *ajtmp++;
492     }
493     /* finished row so stick it into b->a */
494     pv = ba + 49*bi[i];
495     pj = bj + bi[i];
496     nz = bi[i+1] - bi[i];
497     for ( j=0; j<nz; j++ ) {
498       x      = rtmp+49*pj[j];
499       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
500       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
501       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
502       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
503       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
504       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
505       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
506       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
507       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
508       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
509       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
510       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
511       pv[48] = x[48];
512       pv   += 49;
513     }
514     /* invert diagonal block */
515     w = ba + 49*diag_offset[i];
516     ierr = Kernel_A_gets_inverse_A_7(w);CHKERRQ(ierr);
517   }
518 
519   ierr = PetscFree(rtmp);CHKERRQ(ierr);
520   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
521   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
522   C->factor = FACTOR_LU;
523   C->assembled = PETSC_TRUE;
524   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
525   PetscFunctionReturn(0);
526 }
527 
528 /*
529       Version for when blocks are 7 by 7 Using natural ordering
530 */
531 #undef __FUNC__
532 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering"
533 int MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering(Mat A,Mat *B)
534 {
535   Mat                C = *B;
536   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
537   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
538   int                *ajtmpold, *ajtmp, nz, row;
539   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
540   register int       *pj;
541   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
542   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
543   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
544   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
545   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
546   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
547   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
548   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
549   MatScalar          p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
550   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
551   MatScalar          x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
552   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
553   MatScalar          m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
554   MatScalar          *ba = b->a,*aa = a->a;
555 
556   PetscFunctionBegin;
557   rtmp  = (MatScalar *) PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
558   for ( i=0; i<n; i++ ) {
559     nz    = bi[i+1] - bi[i];
560     ajtmp = bj + bi[i];
561     for  ( j=0; j<nz; j++ ) {
562       x = rtmp+49*ajtmp[j];
563       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
564       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
565       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
566       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
567       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
568       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
569     }
570     /* load in initial (unfactored row) */
571     nz       = ai[i+1] - ai[i];
572     ajtmpold = aj + ai[i];
573     v        = aa + 49*ai[i];
574     for ( j=0; j<nz; j++ ) {
575       x    = rtmp+49*ajtmpold[j];
576       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
577       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
578       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
579       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
580       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
581       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
582       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
583       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
584       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
585       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
586       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
587       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
588       x[48] = v[48];
589       v    += 49;
590     }
591     row = *ajtmp++;
592     while (row < i) {
593       pc  = rtmp + 49*row;
594       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
595       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
596       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
597       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
598       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
599       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
600       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
601       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
602       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
603       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
604       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
605       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
606       p49 = pc[48];
607       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
608           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
609           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
610           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
611           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
612           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
613           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
614           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
615           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
616           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
617           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
618           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
619           p49 != 0.0) {
620         pv = ba + 49*diag_offset[row];
621         pj = bj + diag_offset[row] + 1;
622 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
623 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
624 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
625 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
626 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
627 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
628 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
629 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
630 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
631 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
632 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
633 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
634         x49 = pv[48];
635         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
636         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
637         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
638         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
639         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
640         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
641         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
642 
643         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
644         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
645         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
646         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
647         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
648         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
649         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
650 
651         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
652         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
653         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
654         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
655         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
656         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
657         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
658 
659         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
660         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
661         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
662         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
663         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
664         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
665         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
666 
667         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
668         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
669         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
670         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
671         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
672         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
673         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
674 
675         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
676         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
677         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
678         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
679         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
680         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
681         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
682 
683         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
684         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
685         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
686         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
687         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
688         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
689         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
690 
691         nz = bi[row+1] - diag_offset[row] - 1;
692         pv += 49;
693         for (j=0; j<nz; j++) {
694 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
695 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
696 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
697 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
698 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
699 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
700 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
701 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
702 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
703 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
704 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
705 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
706 	  x49 = pv[48];
707 	  x    = rtmp + 49*pj[j];
708 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
709 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
710 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
711 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
712 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
713 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
714 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
715 
716 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
717 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
718 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
719 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
720 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
721 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
722 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
723 
724 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
725 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
726 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
727 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
728 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
729 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
730 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
731 
732 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
733 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
734 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
735 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
736 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
737 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
738 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
739 
740 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
741 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
742 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
743 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
744 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
745 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
746 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
747 
748 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
749 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
750 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
751 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
752 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
753 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
754 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
755 
756 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
757 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
758 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
759 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
760 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
761 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
762 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
763           pv   += 49;
764         }
765         PLogFlops(686*nz+637);
766       }
767       row = *ajtmp++;
768     }
769     /* finished row so stick it into b->a */
770     pv = ba + 49*bi[i];
771     pj = bj + bi[i];
772     nz = bi[i+1] - bi[i];
773     for ( j=0; j<nz; j++ ) {
774       x      = rtmp+49*pj[j];
775       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
776       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
777       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
778       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
779       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
780       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
781       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
782       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
783       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
784       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
785       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
786       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
787       pv[48] = x[48];
788       pv   += 49;
789     }
790     /* invert diagonal block */
791     w = ba + 49*diag_offset[i];
792     ierr = Kernel_A_gets_inverse_A_7(w);CHKERRQ(ierr);
793   }
794 
795   ierr = PetscFree(rtmp);CHKERRQ(ierr);
796   C->factor    = FACTOR_LU;
797   C->assembled = PETSC_TRUE;
798   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
799   PetscFunctionReturn(0);
800 }
801 
802 /* ------------------------------------------------------------*/
803 /*
804       Version for when blocks are 6 by 6
805 */
806 #undef __FUNC__
807 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6"
808 int MatLUFactorNumeric_SeqBAIJ_6(Mat A,Mat *B)
809 {
810   Mat                C = *B;
811   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
812   IS                 isrow = b->row, isicol = b->icol;
813   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
814   int                *ajtmpold, *ajtmp, nz, row;
815   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
816   register int       *pj;
817   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
818   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
819   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
820   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
821   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
822   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
823   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
824   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
825   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
826   MatScalar          *ba = b->a,*aa = a->a;
827 
828   PetscFunctionBegin;
829   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
830   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
831   rtmp  = (MatScalar *) PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
832 
833   for ( i=0; i<n; i++ ) {
834     nz    = bi[i+1] - bi[i];
835     ajtmp = bj + bi[i];
836     for  ( j=0; j<nz; j++ ) {
837       x = rtmp+36*ajtmp[j];
838       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
839       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
840       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
841       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
842       x[34] = x[35] = 0.0 ;
843     }
844     /* load in initial (unfactored row) */
845     idx      = r[i];
846     nz       = ai[idx+1] - ai[idx];
847     ajtmpold = aj + ai[idx];
848     v        = aa + 36*ai[idx];
849     for ( j=0; j<nz; j++ ) {
850       x    = rtmp+36*ic[ajtmpold[j]];
851       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
852       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
853       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
854       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
855       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
856       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
857       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
858       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
859       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
860       v    += 36;
861     }
862     row = *ajtmp++;
863     while (row < i) {
864       pc  =  rtmp + 36*row;
865       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
866       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
867       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
868       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
869       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
870       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
871       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
872       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
873       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
874       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
875           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
876           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
877           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
878           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
879           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
880           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
881           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
882           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
883         pv = ba + 36*diag_offset[row];
884         pj = bj + diag_offset[row] + 1;
885 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
886 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
887 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
888 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
889 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
890 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
891 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
892 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
893 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
894         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
895         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
896         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
897         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
898         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
899         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
900 
901         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
902         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
903         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
904         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
905         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
906         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
907 
908         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
909         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
910         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
911         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
912         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
913         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
914 
915         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
916         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
917         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
918         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
919         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
920         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
921 
922         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
923         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
924         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
925         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
926         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
927         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
928 
929         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
930         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
931         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
932         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
933         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
934         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
935 
936         nz = bi[row+1] - diag_offset[row] - 1;
937         pv += 36;
938         for (j=0; j<nz; j++) {
939 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
940 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
941 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
942 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
943 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
944 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
945 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
946 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
947 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
948 	  x    = rtmp + 36*pj[j];
949           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
950           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
951           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
952           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
953           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
954           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
955 
956 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
957 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
958 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
959 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
960 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
961 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
962 
963 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
964 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
965 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
966 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
967 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
968 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
969 
970 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
971 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
972 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
973 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
974 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
975 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
976 
977 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
978 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
979 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
980 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
981 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
982 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
983 
984 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
985 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
986 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
987 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
988 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
989 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
990 
991           pv   += 36;
992         }
993         PLogFlops(432*nz+396);
994       }
995       row = *ajtmp++;
996     }
997     /* finished row so stick it into b->a */
998     pv = ba + 36*bi[i];
999     pj = bj + bi[i];
1000     nz = bi[i+1] - bi[i];
1001     for ( j=0; j<nz; j++ ) {
1002       x      = rtmp+36*pj[j];
1003       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1004       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1005       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1006       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1007       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1008       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1009       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1010       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1011       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1012       pv   += 36;
1013     }
1014     /* invert diagonal block */
1015     w = ba + 36*diag_offset[i];
1016     ierr = Kernel_A_gets_inverse_A_6(w);CHKERRQ(ierr);
1017   }
1018 
1019   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1020   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1021   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1022   C->factor = FACTOR_LU;
1023   C->assembled = PETSC_TRUE;
1024   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1025   PetscFunctionReturn(0);
1026 }
1027 /*
1028       Version for when blocks are 6 by 6 Using natural ordering
1029 */
1030 #undef __FUNC__
1031 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering"
1032 int MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat A,Mat *B)
1033 {
1034   Mat                C = *B;
1035   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1036   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1037   int                *ajtmpold, *ajtmp, nz, row;
1038   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1039   register int       *pj;
1040   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1041   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1042   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1043   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1044   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1045   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1046   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1047   MatScalar          p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
1048   MatScalar          x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
1049   MatScalar          m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
1050   MatScalar          *ba = b->a,*aa = a->a;
1051 
1052   PetscFunctionBegin;
1053   rtmp  = (MatScalar *) PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1054   for ( i=0; i<n; i++ ) {
1055     nz    = bi[i+1] - bi[i];
1056     ajtmp = bj + bi[i];
1057     for  ( j=0; j<nz; j++ ) {
1058       x = rtmp+36*ajtmp[j];
1059       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1060       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1061       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
1062       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
1063       x[34] = x[35] = 0.0 ;
1064     }
1065     /* load in initial (unfactored row) */
1066     nz       = ai[i+1] - ai[i];
1067     ajtmpold = aj + ai[i];
1068     v        = aa + 36*ai[i];
1069     for ( j=0; j<nz; j++ ) {
1070       x    = rtmp+36*ajtmpold[j];
1071       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
1072       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
1073       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
1074       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
1075       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
1076       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1077       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
1078       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
1079       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
1080       v    += 36;
1081     }
1082     row = *ajtmp++;
1083     while (row < i) {
1084       pc  = rtmp + 36*row;
1085       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1086       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
1087       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
1088       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
1089       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
1090       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1091       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
1092       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
1093       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
1094       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
1095           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
1096           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
1097           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
1098           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
1099           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
1100           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
1101           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
1102           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
1103         pv = ba + 36*diag_offset[row];
1104         pj = bj + diag_offset[row] + 1;
1105 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1106 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1107 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1108 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1109 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1110 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1111 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1112 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1113 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1114         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
1115         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
1116         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
1117         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
1118         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
1119         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
1120 
1121         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
1122         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
1123         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
1124         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
1125         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
1126         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
1127 
1128         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
1129         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
1130         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
1131         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
1132         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
1133         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
1134 
1135         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
1136         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
1137         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
1138         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
1139         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
1140         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
1141 
1142         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
1143         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
1144         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
1145         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
1146         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
1147         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
1148 
1149         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
1150         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
1151         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
1152         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
1153         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
1154         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
1155 
1156         nz = bi[row+1] - diag_offset[row] - 1;
1157         pv += 36;
1158         for (j=0; j<nz; j++) {
1159 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1160 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1161 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1162 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1163 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1164 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1165 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1166 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1167 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1168 	  x    = rtmp + 36*pj[j];
1169           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
1170           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
1171           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
1172           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
1173           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
1174           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
1175 
1176 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
1177 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
1178 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
1179 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
1180 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
1181 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
1182 
1183 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
1184 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
1185 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
1186 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
1187 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
1188 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
1189 
1190 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
1191 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
1192 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
1193 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
1194 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
1195 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
1196 
1197 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
1198 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
1199 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
1200 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
1201 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
1202 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
1203 
1204 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
1205 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
1206 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
1207 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
1208 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
1209 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
1210 
1211           pv   += 36;
1212         }
1213         PLogFlops(432*nz+396);
1214       }
1215       row = *ajtmp++;
1216     }
1217     /* finished row so stick it into b->a */
1218     pv = ba + 36*bi[i];
1219     pj = bj + bi[i];
1220     nz = bi[i+1] - bi[i];
1221     for ( j=0; j<nz; j++ ) {
1222       x      = rtmp+36*pj[j];
1223       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1224       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1225       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1226       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1227       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1228       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1229       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1230       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1231       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1232       pv   += 36;
1233     }
1234     /* invert diagonal block */
1235     w = ba + 36*diag_offset[i];
1236     ierr = Kernel_A_gets_inverse_A_6(w);CHKERRQ(ierr);
1237   }
1238 
1239   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1240   C->factor    = FACTOR_LU;
1241   C->assembled = PETSC_TRUE;
1242   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1243   PetscFunctionReturn(0);
1244 }
1245 
1246 /* ------------------------------------------------------------*/
1247 /*
1248       Version for when blocks are 5 by 5
1249 */
1250 #undef __FUNC__
1251 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5"
1252 int MatLUFactorNumeric_SeqBAIJ_5(Mat A,Mat *B)
1253 {
1254   Mat                C = *B;
1255   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1256   IS                 isrow = b->row, isicol = b->icol;
1257   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1258   int                *ajtmpold, *ajtmp, nz, row;
1259   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
1260   register int       *pj;
1261   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1262   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1263   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1264   MatScalar          x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
1265   MatScalar          p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
1266   MatScalar          m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1267   MatScalar          *ba = b->a,*aa = a->a;
1268 
1269   PetscFunctionBegin;
1270   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1271   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1272   rtmp  = (MatScalar *) PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1273 
1274   for ( i=0; i<n; i++ ) {
1275     nz    = bi[i+1] - bi[i];
1276     ajtmp = bj + bi[i];
1277     for  ( j=0; j<nz; j++ ) {
1278       x = rtmp+25*ajtmp[j];
1279       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1280       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1281       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1282     }
1283     /* load in initial (unfactored row) */
1284     idx      = r[i];
1285     nz       = ai[idx+1] - ai[idx];
1286     ajtmpold = aj + ai[idx];
1287     v        = aa + 25*ai[idx];
1288     for ( j=0; j<nz; j++ ) {
1289       x    = rtmp+25*ic[ajtmpold[j]];
1290       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1291       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1292       x[9] = v[9]; x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1293       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17];
1294       x[18] = v[18]; x[19] = v[19]; x[20] = v[20]; x[21] = v[21];
1295       x[22] = v[22]; x[23] = v[23]; x[24] = v[24];
1296       v    += 25;
1297     }
1298     row = *ajtmp++;
1299     while (row < i) {
1300       pc = rtmp + 25*row;
1301       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1302       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1303       p10 = pc[9]; p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1304       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17]; p19 = pc[18];
1305       p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1306       p25 = pc[24];
1307       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1308           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1309           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1310           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 ||
1311           p20 != 0.0 || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 ||
1312           p24 != 0.0 || p25 != 0.0) {
1313         pv = ba + 25*diag_offset[row];
1314         pj = bj + diag_offset[row] + 1;
1315         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1316         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1317         x10 = pv[9]; x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1318         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1319         x19 = pv[18]; x20 = pv[19]; x21 = pv[20]; x22 = pv[21];
1320         x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1321         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1322         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1323         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1324         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1325         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1326 
1327         pc[5] = m6 = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1328         pc[6] = m7 = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1329         pc[7] = m8 = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1330         pc[8] = m9 = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1331         pc[9] = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1332 
1333         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1334         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1335         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1336         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1337         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1338 
1339         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1340         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1341         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1342         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1343         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1344 
1345         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1346         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1347         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1348         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1349         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1350 
1351         nz = bi[row+1] - diag_offset[row] - 1;
1352         pv += 25;
1353         for (j=0; j<nz; j++) {
1354           x1   = pv[0];  x2 = pv[1];   x3  = pv[2];  x4  = pv[3];
1355           x5   = pv[4];  x6 = pv[5];   x7  = pv[6];  x8  = pv[7]; x9 = pv[8];
1356           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1357           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16];
1358           x18  = pv[17]; x19 = pv[18]; x20 = pv[19]; x21 = pv[20];
1359           x22  = pv[21]; x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1360           x    = rtmp + 25*pj[j];
1361           x[0] -= m1*x1 + m6*x2  + m11*x3 + m16*x4 + m21*x5;
1362           x[1] -= m2*x1 + m7*x2  + m12*x3 + m17*x4 + m22*x5;
1363           x[2] -= m3*x1 + m8*x2  + m13*x3 + m18*x4 + m23*x5;
1364           x[3] -= m4*x1 + m9*x2  + m14*x3 + m19*x4 + m24*x5;
1365           x[4] -= m5*x1 + m10*x2 + m15*x3 + m20*x4 + m25*x5;
1366 
1367           x[5] -= m1*x6 + m6*x7  + m11*x8 + m16*x9 + m21*x10;
1368           x[6] -= m2*x6 + m7*x7  + m12*x8 + m17*x9 + m22*x10;
1369           x[7] -= m3*x6 + m8*x7  + m13*x8 + m18*x9 + m23*x10;
1370           x[8] -= m4*x6 + m9*x7  + m14*x8 + m19*x9 + m24*x10;
1371           x[9] -= m5*x6 + m10*x7 + m15*x8 + m20*x9 + m25*x10;
1372 
1373           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1374           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1375           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1376           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1377           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1378 
1379           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1380           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1381           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1382           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1383           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1384 
1385           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1386           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1387           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1388           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1389           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1390 
1391           pv   += 25;
1392         }
1393         PLogFlops(250*nz+225);
1394       }
1395       row = *ajtmp++;
1396     }
1397     /* finished row so stick it into b->a */
1398     pv = ba + 25*bi[i];
1399     pj = bj + bi[i];
1400     nz = bi[i+1] - bi[i];
1401     for ( j=0; j<nz; j++ ) {
1402       x     = rtmp+25*pj[j];
1403       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1404       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1405       pv[9] = x[9]; pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1406       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16];
1407       pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20];
1408       pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23]; pv[24] = x[24];
1409       pv   += 25;
1410     }
1411     /* invert diagonal block */
1412     w = ba + 25*diag_offset[i];
1413     ierr = Kernel_A_gets_inverse_A_5(w);CHKERRQ(ierr);
1414   }
1415 
1416   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1417   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1418   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1419   C->factor = FACTOR_LU;
1420   C->assembled = PETSC_TRUE;
1421   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1422   PetscFunctionReturn(0);
1423 }
1424 /*
1425       Version for when blocks are 5 by 5 Using natural ordering
1426 */
1427 #undef __FUNC__
1428 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering"
1429 int MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering(Mat A,Mat *B)
1430 {
1431   Mat                C = *B;
1432   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1433   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1434   int                *ajtmpold, *ajtmp, nz, row;
1435   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1436   register int       *pj;
1437   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1438   MatScalar          x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1439   MatScalar          x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1440   MatScalar          p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1441   MatScalar          p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1442   MatScalar          m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1443   MatScalar          m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1444   MatScalar          *ba = b->a,*aa = a->a;
1445 
1446   PetscFunctionBegin;
1447   rtmp  = (MatScalar *) PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1448   for ( i=0; i<n; i++ ) {
1449     nz    = bi[i+1] - bi[i];
1450     ajtmp = bj + bi[i];
1451     for  ( j=0; j<nz; j++ ) {
1452       x = rtmp+25*ajtmp[j];
1453       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1454       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1455       x[16] = x[17] = x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1456     }
1457     /* load in initial (unfactored row) */
1458     nz       = ai[i+1] - ai[i];
1459     ajtmpold = aj + ai[i];
1460     v        = aa + 25*ai[i];
1461     for ( j=0; j<nz; j++ ) {
1462       x    = rtmp+25*ajtmpold[j];
1463       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1464       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1465       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1466       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17]; x[18] = v[18];
1467       x[19] = v[19]; x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1468       x[24] = v[24];
1469       v    += 25;
1470     }
1471     row = *ajtmp++;
1472     while (row < i) {
1473       pc  = rtmp + 25*row;
1474       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1475       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1476       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1477       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17];
1478       p19 = pc[18]; p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22];
1479       p24 = pc[23]; p25 = pc[24];
1480       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1481           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1482           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1483           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0
1484           || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 || p25 != 0.0) {
1485         pv = ba + 25*diag_offset[row];
1486         pj = bj + diag_offset[row] + 1;
1487         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1488         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1489         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1490         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17]; x19 = pv[18];
1491         x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1492         x25 = pv[24];
1493         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1494         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1495         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1496         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1497         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1498 
1499         pc[5]  = m6  = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1500         pc[6]  = m7  = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1501         pc[7]  = m8  = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1502         pc[8]  = m9  = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1503         pc[9]  = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1504 
1505         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1506         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1507         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1508         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1509         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1510 
1511         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1512         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1513         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1514         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1515         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1516 
1517         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1518         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1519         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1520         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1521         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1522 
1523         nz = bi[row+1] - diag_offset[row] - 1;
1524         pv += 25;
1525         for (j=0; j<nz; j++) {
1526           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1527           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1528           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1529           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1530           x19 = pv[18];  x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22];
1531           x24 = pv[23];  x25 = pv[24];
1532           x    = rtmp + 25*pj[j];
1533           x[0] -= m1*x1 + m6*x2   + m11*x3  + m16*x4 + m21*x5;
1534           x[1] -= m2*x1 + m7*x2   + m12*x3  + m17*x4 + m22*x5;
1535           x[2] -= m3*x1 + m8*x2   + m13*x3  + m18*x4 + m23*x5;
1536           x[3] -= m4*x1 + m9*x2   + m14*x3  + m19*x4 + m24*x5;
1537           x[4] -= m5*x1 + m10*x2  + m15*x3  + m20*x4 + m25*x5;
1538 
1539           x[5] -= m1*x6 + m6*x7   + m11*x8  + m16*x9 + m21*x10;
1540           x[6] -= m2*x6 + m7*x7   + m12*x8  + m17*x9 + m22*x10;
1541           x[7] -= m3*x6 + m8*x7   + m13*x8  + m18*x9 + m23*x10;
1542           x[8] -= m4*x6 + m9*x7   + m14*x8  + m19*x9 + m24*x10;
1543           x[9] -= m5*x6 + m10*x7  + m15*x8  + m20*x9 + m25*x10;
1544 
1545           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1546           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1547           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1548           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1549           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1550 
1551           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1552           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1553           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1554           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1555           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1556 
1557           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1558           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1559           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1560           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1561           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1562           pv   += 25;
1563         }
1564         PLogFlops(250*nz+225);
1565       }
1566       row = *ajtmp++;
1567     }
1568     /* finished row so stick it into b->a */
1569     pv = ba + 25*bi[i];
1570     pj = bj + bi[i];
1571     nz = bi[i+1] - bi[i];
1572     for ( j=0; j<nz; j++ ) {
1573       x      = rtmp+25*pj[j];
1574       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1575       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1576       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1577       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16]; pv[17] = x[17];
1578       pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22];
1579       pv[23] = x[23]; pv[24] = x[24];
1580       pv   += 25;
1581     }
1582     /* invert diagonal block */
1583     w = ba + 25*diag_offset[i];
1584     ierr = Kernel_A_gets_inverse_A_5(w);CHKERRQ(ierr);
1585   }
1586 
1587   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1588   C->factor    = FACTOR_LU;
1589   C->assembled = PETSC_TRUE;
1590   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1591   PetscFunctionReturn(0);
1592 }
1593 
1594 /* ------------------------------------------------------------*/
1595 /*
1596       Version for when blocks are 4 by 4
1597 */
1598 #undef __FUNC__
1599 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4"
1600 int MatLUFactorNumeric_SeqBAIJ_4(Mat A,Mat *B)
1601 {
1602   Mat                C = *B;
1603   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1604   IS                 isrow = b->row, isicol = b->icol;
1605   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1606   int                *ajtmpold, *ajtmp, nz, row;
1607   int                *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j;
1608   register int       *pj;
1609   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1610   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1611   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1612   MatScalar          p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
1613   MatScalar          m13,m14,m15,m16;
1614   MatScalar          *ba = b->a,*aa = a->a;
1615 
1616   PetscFunctionBegin;
1617   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1618   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1619   rtmp  = (MatScalar *) PetscMalloc(16*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1620 
1621   for ( i=0; i<n; i++ ) {
1622     nz    = bi[i+1] - bi[i];
1623     ajtmp = bj + bi[i];
1624     for  ( j=0; j<nz; j++ ) {
1625       x = rtmp+16*ajtmp[j];
1626       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1627       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1628     }
1629     /* load in initial (unfactored row) */
1630     idx      = r[i];
1631     nz       = ai[idx+1] - ai[idx];
1632     ajtmpold = aj + ai[idx];
1633     v        = aa + 16*ai[idx];
1634     for ( j=0; j<nz; j++ ) {
1635       x    = rtmp+16*ic[ajtmpold[j]];
1636       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1637       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1638       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1639       x[14] = v[14]; x[15] = v[15];
1640       v    += 16;
1641     }
1642     row = *ajtmp++;
1643     while (row < i) {
1644       pc  = rtmp + 16*row;
1645       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1646       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1647       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1648       p15 = pc[14]; p16 = pc[15];
1649       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1650           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1651           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1652           || p16 != 0.0) {
1653         pv = ba + 16*diag_offset[row];
1654         pj = bj + diag_offset[row] + 1;
1655         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1656         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1657         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1658         x15 = pv[14]; x16 = pv[15];
1659         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
1660         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
1661         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
1662         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
1663 
1664         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
1665         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
1666         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
1667         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
1668 
1669         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
1670         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
1671         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
1672         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
1673 
1674         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
1675         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
1676         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
1677         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
1678 
1679         nz = bi[row+1] - diag_offset[row] - 1;
1680         pv += 16;
1681         for (j=0; j<nz; j++) {
1682           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1683           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1684           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1685           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
1686           x    = rtmp + 16*pj[j];
1687           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
1688           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
1689           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
1690           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
1691 
1692           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
1693           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
1694           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
1695           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
1696 
1697           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
1698           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
1699           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
1700           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
1701 
1702           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
1703           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
1704           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
1705           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
1706 
1707           pv   += 16;
1708         }
1709         PLogFlops(128*nz+112);
1710       }
1711       row = *ajtmp++;
1712     }
1713     /* finished row so stick it into b->a */
1714     pv = ba + 16*bi[i];
1715     pj = bj + bi[i];
1716     nz = bi[i+1] - bi[i];
1717     for ( j=0; j<nz; j++ ) {
1718       x      = rtmp+16*pj[j];
1719       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1720       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1721       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1722       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1723       pv   += 16;
1724     }
1725     /* invert diagonal block */
1726     w = ba + 16*diag_offset[i];
1727     ierr = Kernel_A_gets_inverse_A_4(w);CHKERRQ(ierr);
1728   }
1729 
1730   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1731   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1732   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1733   C->factor = FACTOR_LU;
1734   C->assembled = PETSC_TRUE;
1735   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
1736   PetscFunctionReturn(0);
1737 }
1738 /*
1739       Version for when blocks are 4 by 4 Using natural ordering
1740 */
1741 #undef __FUNC__
1742 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering"
1743 int MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering(Mat A,Mat *B)
1744 {
1745   Mat                C = *B;
1746   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1747   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1748   int                *ajtmpold, *ajtmp, nz, row;
1749   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
1750   register int       *pj;
1751   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1752   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1753   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1754   MatScalar          p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
1755   MatScalar          m13,m14,m15,m16;
1756   MatScalar          *ba = b->a,*aa = a->a;
1757 
1758   PetscFunctionBegin;
1759   rtmp  = (MatScalar *) PetscMalloc(16*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1760 
1761   for ( i=0; i<n; i++ ) {
1762     nz    = bi[i+1] - bi[i];
1763     ajtmp = bj + bi[i];
1764     for  ( j=0; j<nz; j++ ) {
1765       x = rtmp+16*ajtmp[j];
1766       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1767       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1768     }
1769     /* load in initial (unfactored row) */
1770     nz       = ai[i+1] - ai[i];
1771     ajtmpold = aj + ai[i];
1772     v        = aa + 16*ai[i];
1773     for ( j=0; j<nz; j++ ) {
1774       x    = rtmp+16*ajtmpold[j];
1775       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1776       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1777       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1778       x[14] = v[14]; x[15] = v[15];
1779       v    += 16;
1780     }
1781     row = *ajtmp++;
1782     while (row < i) {
1783       pc  = rtmp + 16*row;
1784       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1785       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1786       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1787       p15 = pc[14]; p16 = pc[15];
1788       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1789           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1790           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1791           || p16 != 0.0) {
1792         pv = ba + 16*diag_offset[row];
1793         pj = bj + diag_offset[row] + 1;
1794         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1795         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1796         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1797         x15 = pv[14]; x16 = pv[15];
1798         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
1799         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
1800         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
1801         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
1802 
1803         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
1804         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
1805         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
1806         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
1807 
1808         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
1809         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
1810         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
1811         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
1812 
1813         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
1814         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
1815         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
1816         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
1817 
1818         nz = bi[row+1] - diag_offset[row] - 1;
1819         pv += 16;
1820         for (j=0; j<nz; j++) {
1821           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1822           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1823           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1824           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
1825           x    = rtmp + 16*pj[j];
1826           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
1827           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
1828           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
1829           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
1830 
1831           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
1832           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
1833           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
1834           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
1835 
1836           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
1837           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
1838           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
1839           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
1840 
1841           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
1842           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
1843           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
1844           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
1845 
1846           pv   += 16;
1847         }
1848         PLogFlops(128*nz+112);
1849       }
1850       row = *ajtmp++;
1851     }
1852     /* finished row so stick it into b->a */
1853     pv = ba + 16*bi[i];
1854     pj = bj + bi[i];
1855     nz = bi[i+1] - bi[i];
1856     for ( j=0; j<nz; j++ ) {
1857       x      = rtmp+16*pj[j];
1858       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1859       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1860       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1861       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1862       pv   += 16;
1863     }
1864     /* invert diagonal block */
1865     w = ba + 16*diag_offset[i];
1866     ierr = Kernel_A_gets_inverse_A_4(w);CHKERRQ(ierr);
1867   }
1868 
1869   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1870   C->factor    = FACTOR_LU;
1871   C->assembled = PETSC_TRUE;
1872   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
1873   PetscFunctionReturn(0);
1874 }
1875 
1876 
1877 /* ------------------------------------------------------------*/
1878 /*
1879       Version for when blocks are 3 by 3
1880 */
1881 #undef __FUNC__
1882 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3"
1883 int MatLUFactorNumeric_SeqBAIJ_3(Mat A,Mat *B)
1884 {
1885   Mat                C = *B;
1886   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1887   IS                 isrow = b->row, isicol = b->icol;
1888   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1889   int                *ajtmpold, *ajtmp, nz, row, *ai=a->i,*aj=a->j;
1890   int                *diag_offset = b->diag,idx;
1891   register int       *pj;
1892   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
1893   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1894   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
1895   MatScalar          *ba = b->a,*aa = a->a;
1896 
1897   PetscFunctionBegin;
1898   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1899   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1900   rtmp  = (MatScalar *) PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1901 
1902   for ( i=0; i<n; i++ ) {
1903     nz    = bi[i+1] - bi[i];
1904     ajtmp = bj + bi[i];
1905     for  ( j=0; j<nz; j++ ) {
1906       x = rtmp + 9*ajtmp[j];
1907       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = 0.0;
1908     }
1909     /* load in initial (unfactored row) */
1910     idx      = r[i];
1911     nz       = ai[idx+1] - ai[idx];
1912     ajtmpold = aj + ai[idx];
1913     v        = aa + 9*ai[idx];
1914     for ( j=0; j<nz; j++ ) {
1915       x    = rtmp + 9*ic[ajtmpold[j]];
1916       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1917       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1918       v    += 9;
1919     }
1920     row = *ajtmp++;
1921     while (row < i) {
1922       pc = rtmp + 9*row;
1923       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1924       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1925       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1926           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
1927         pv = ba + 9*diag_offset[row];
1928         pj = bj + diag_offset[row] + 1;
1929         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1930         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1931         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
1932         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
1933         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
1934 
1935         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
1936         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
1937         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
1938 
1939         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
1940         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
1941         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
1942         nz = bi[row+1] - diag_offset[row] - 1;
1943         pv += 9;
1944         for (j=0; j<nz; j++) {
1945           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1946           x5   = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1947           x    = rtmp + 9*pj[j];
1948           x[0] -= m1*x1 + m4*x2 + m7*x3;
1949           x[1] -= m2*x1 + m5*x2 + m8*x3;
1950           x[2] -= m3*x1 + m6*x2 + m9*x3;
1951 
1952           x[3] -= m1*x4 + m4*x5 + m7*x6;
1953           x[4] -= m2*x4 + m5*x5 + m8*x6;
1954           x[5] -= m3*x4 + m6*x5 + m9*x6;
1955 
1956           x[6] -= m1*x7 + m4*x8 + m7*x9;
1957           x[7] -= m2*x7 + m5*x8 + m8*x9;
1958           x[8] -= m3*x7 + m6*x8 + m9*x9;
1959           pv   += 9;
1960         }
1961         PLogFlops(54*nz+36);
1962       }
1963       row = *ajtmp++;
1964     }
1965     /* finished row so stick it into b->a */
1966     pv = ba + 9*bi[i];
1967     pj = bj + bi[i];
1968     nz = bi[i+1] - bi[i];
1969     for ( j=0; j<nz; j++ ) {
1970       x     = rtmp + 9*pj[j];
1971       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1972       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1973       pv   += 9;
1974     }
1975     /* invert diagonal block */
1976     w = ba + 9*diag_offset[i];
1977     ierr = Kernel_A_gets_inverse_A_3(w);CHKERRQ(ierr);
1978   }
1979 
1980   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1981   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1982   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1983   C->factor = FACTOR_LU;
1984   C->assembled = PETSC_TRUE;
1985   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
1986   PetscFunctionReturn(0);
1987 }
1988 /*
1989       Version for when blocks are 3 by 3 Using natural ordering
1990 */
1991 #undef __FUNC__
1992 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering"
1993 int MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering(Mat A,Mat *B)
1994 {
1995   Mat                C = *B;
1996   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
1997   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
1998   int                *ajtmpold, *ajtmp, nz, row;
1999   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
2000   register int       *pj;
2001   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
2002   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
2003   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
2004   MatScalar          *ba = b->a,*aa = a->a;
2005 
2006   PetscFunctionBegin;
2007   rtmp  = (MatScalar *) PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2008 
2009   for ( i=0; i<n; i++ ) {
2010     nz    = bi[i+1] - bi[i];
2011     ajtmp = bj + bi[i];
2012     for  ( j=0; j<nz; j++ ) {
2013       x = rtmp+9*ajtmp[j];
2014       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = 0.0;
2015     }
2016     /* load in initial (unfactored row) */
2017     nz       = ai[i+1] - ai[i];
2018     ajtmpold = aj + ai[i];
2019     v        = aa + 9*ai[i];
2020     for ( j=0; j<nz; j++ ) {
2021       x    = rtmp+9*ajtmpold[j];
2022       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2023       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
2024       v    += 9;
2025     }
2026     row = *ajtmp++;
2027     while (row < i) {
2028       pc  = rtmp + 9*row;
2029       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2030       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
2031       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
2032           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
2033         pv = ba + 9*diag_offset[row];
2034         pj = bj + diag_offset[row] + 1;
2035         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2036         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
2037         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
2038         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
2039         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
2040 
2041         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
2042         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
2043         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
2044 
2045         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
2046         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
2047         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
2048 
2049         nz = bi[row+1] - diag_offset[row] - 1;
2050         pv += 9;
2051         for (j=0; j<nz; j++) {
2052           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2053           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
2054           x    = rtmp + 9*pj[j];
2055           x[0] -= m1*x1 + m4*x2 + m7*x3;
2056           x[1] -= m2*x1 + m5*x2 + m8*x3;
2057           x[2] -= m3*x1 + m6*x2 + m9*x3;
2058 
2059           x[3] -= m1*x4 + m4*x5 + m7*x6;
2060           x[4] -= m2*x4 + m5*x5 + m8*x6;
2061           x[5] -= m3*x4 + m6*x5 + m9*x6;
2062 
2063           x[6] -= m1*x7 + m4*x8 + m7*x9;
2064           x[7] -= m2*x7 + m5*x8 + m8*x9;
2065           x[8] -= m3*x7 + m6*x8 + m9*x9;
2066           pv   += 9;
2067         }
2068         PLogFlops(54*nz+36);
2069       }
2070       row = *ajtmp++;
2071     }
2072     /* finished row so stick it into b->a */
2073     pv = ba + 9*bi[i];
2074     pj = bj + bi[i];
2075     nz = bi[i+1] - bi[i];
2076     for ( j=0; j<nz; j++ ) {
2077       x      = rtmp+9*pj[j];
2078       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2079       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
2080       pv   += 9;
2081     }
2082     /* invert diagonal block */
2083     w = ba + 9*diag_offset[i];
2084     ierr = Kernel_A_gets_inverse_A_3(w);CHKERRQ(ierr);
2085   }
2086 
2087   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2088   C->factor    = FACTOR_LU;
2089   C->assembled = PETSC_TRUE;
2090   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
2091   PetscFunctionReturn(0);
2092 }
2093 
2094 /* ------------------------------------------------------------*/
2095 /*
2096       Version for when blocks are 2 by 2
2097 */
2098 #undef __FUNC__
2099 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2"
2100 int MatLUFactorNumeric_SeqBAIJ_2(Mat A,Mat *B)
2101 {
2102   Mat                C = *B;
2103   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
2104   IS                 isrow = b->row, isicol = b->icol;
2105   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2106   int                *ajtmpold, *ajtmp, nz, row;
2107   int                *diag_offset=b->diag,idx,*ai=a->i,*aj=a->j;
2108   register int       *pj;
2109   register MatScalar *pv,*v,*rtmp,m1,m2,m3,m4,*pc,*w,*x,x1,x2,x3,x4;
2110   MatScalar          p1,p2,p3,p4;
2111   MatScalar          *ba = b->a,*aa = a->a;
2112 
2113   PetscFunctionBegin;
2114   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
2115   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
2116   rtmp  = (MatScalar *) PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2117 
2118   for ( i=0; i<n; i++ ) {
2119     nz    = bi[i+1] - bi[i];
2120     ajtmp = bj + bi[i];
2121     for  ( j=0; j<nz; j++ ) {
2122       x = rtmp+4*ajtmp[j]; x[0] = x[1] = x[2] = x[3] = 0.0;
2123     }
2124     /* load in initial (unfactored row) */
2125     idx      = r[i];
2126     nz       = ai[idx+1] - ai[idx];
2127     ajtmpold = aj + ai[idx];
2128     v        = aa + 4*ai[idx];
2129     for ( j=0; j<nz; j++ ) {
2130       x    = rtmp+4*ic[ajtmpold[j]];
2131       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
2132       v    += 4;
2133     }
2134     row = *ajtmp++;
2135     while (row < i) {
2136       pc = rtmp + 4*row;
2137       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
2138       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2139         pv = ba + 4*diag_offset[row];
2140         pj = bj + diag_offset[row] + 1;
2141         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2142         pc[0] = m1 = p1*x1 + p3*x2;
2143         pc[1] = m2 = p2*x1 + p4*x2;
2144         pc[2] = m3 = p1*x3 + p3*x4;
2145         pc[3] = m4 = p2*x3 + p4*x4;
2146         nz = bi[row+1] - diag_offset[row] - 1;
2147         pv += 4;
2148         for (j=0; j<nz; j++) {
2149           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2150           x    = rtmp + 4*pj[j];
2151           x[0] -= m1*x1 + m3*x2;
2152           x[1] -= m2*x1 + m4*x2;
2153           x[2] -= m1*x3 + m3*x4;
2154           x[3] -= m2*x3 + m4*x4;
2155           pv   += 4;
2156         }
2157         PLogFlops(16*nz+12);
2158       }
2159       row = *ajtmp++;
2160     }
2161     /* finished row so stick it into b->a */
2162     pv = ba + 4*bi[i];
2163     pj = bj + bi[i];
2164     nz = bi[i+1] - bi[i];
2165     for ( j=0; j<nz; j++ ) {
2166       x     = rtmp+4*pj[j];
2167       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
2168       pv   += 4;
2169     }
2170     /* invert diagonal block */
2171     w = ba + 4*diag_offset[i];
2172     ierr = Kernel_A_gets_inverse_A_2(w);CHKERRQ(ierr);
2173     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2174   }
2175 
2176   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2177   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
2178   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
2179   C->factor = FACTOR_LU;
2180   C->assembled = PETSC_TRUE;
2181   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2182   PetscFunctionReturn(0);
2183 }
2184 /*
2185       Version for when blocks are 2 by 2 Using natural ordering
2186 */
2187 #undef __FUNC__
2188 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering"
2189 int MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering(Mat A,Mat *B)
2190 {
2191   Mat                C = *B;
2192   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data,*b = (Mat_SeqBAIJ *)C->data;
2193   int                ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2194   int                *ajtmpold, *ajtmp, nz, row;
2195   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j;
2196   register int       *pj;
2197   register MatScalar *pv,*v,*rtmp,*pc,*w,*x;
2198   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,x1,x2,x3,x4;
2199   MatScalar          *ba = b->a,*aa = a->a;
2200 
2201   PetscFunctionBegin;
2202   rtmp  = (MatScalar *) PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2203 
2204   for ( i=0; i<n; i++ ) {
2205     nz    = bi[i+1] - bi[i];
2206     ajtmp = bj + bi[i];
2207     for  ( j=0; j<nz; j++ ) {
2208       x = rtmp+4*ajtmp[j];
2209       x[0]  = x[1]  = x[2]  = x[3]  = 0.0;
2210     }
2211     /* load in initial (unfactored row) */
2212     nz       = ai[i+1] - ai[i];
2213     ajtmpold = aj + ai[i];
2214     v        = aa + 4*ai[i];
2215     for ( j=0; j<nz; j++ ) {
2216       x    = rtmp+4*ajtmpold[j];
2217       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2218       v    += 4;
2219     }
2220     row = *ajtmp++;
2221     while (row < i) {
2222       pc  = rtmp + 4*row;
2223       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2224       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2225         pv = ba + 4*diag_offset[row];
2226         pj = bj + diag_offset[row] + 1;
2227         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2228         pc[0] = m1 = p1*x1 + p3*x2;
2229         pc[1] = m2 = p2*x1 + p4*x2;
2230         pc[2] = m3 = p1*x3 + p3*x4;
2231         pc[3] = m4 = p2*x3 + p4*x4;
2232         nz = bi[row+1] - diag_offset[row] - 1;
2233         pv += 4;
2234         for (j=0; j<nz; j++) {
2235           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2236           x    = rtmp + 4*pj[j];
2237           x[0] -= m1*x1 + m3*x2;
2238           x[1] -= m2*x1 + m4*x2;
2239           x[2] -= m1*x3 + m3*x4;
2240           x[3] -= m2*x3 + m4*x4;
2241           pv   += 4;
2242         }
2243         PLogFlops(16*nz+12);
2244       }
2245       row = *ajtmp++;
2246     }
2247     /* finished row so stick it into b->a */
2248     pv = ba + 4*bi[i];
2249     pj = bj + bi[i];
2250     nz = bi[i+1] - bi[i];
2251     for ( j=0; j<nz; j++ ) {
2252       x      = rtmp+4*pj[j];
2253       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2254       pv   += 4;
2255     }
2256     /* invert diagonal block */
2257     w = ba + 4*diag_offset[i];
2258     ierr = Kernel_A_gets_inverse_A_2(w);CHKERRQ(ierr);
2259     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2260   }
2261 
2262   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2263   C->factor    = FACTOR_LU;
2264   C->assembled = PETSC_TRUE;
2265   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2266   PetscFunctionReturn(0);
2267 }
2268 
2269 /* ----------------------------------------------------------- */
2270 /*
2271      Version for when blocks are 1 by 1.
2272 */
2273 #undef __FUNC__
2274 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_1"
2275 int MatLUFactorNumeric_SeqBAIJ_1(Mat A,Mat *B)
2276 {
2277   Mat                C = *B;
2278   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ *) A->data, *b = (Mat_SeqBAIJ *)C->data;
2279   IS                 isrow = b->row, isicol = b->icol;
2280   int                *r,*ic, ierr, i, j, n = a->mbs, *bi = b->i, *bj = b->j;
2281   int                *ajtmpold, *ajtmp, nz, row,*ai = a->i,*aj = a->j;
2282   int                *diag_offset = b->diag,diag;
2283   register int       *pj;
2284   register MatScalar *pv,*v,*rtmp,multiplier,*pc;
2285   MatScalar          *ba = b->a,*aa = a->a;
2286 
2287   PetscFunctionBegin;
2288   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
2289   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
2290   rtmp  = (MatScalar *) PetscMalloc((n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2291 
2292   for ( i=0; i<n; i++ ) {
2293     nz    = bi[i+1] - bi[i];
2294     ajtmp = bj + bi[i];
2295     for  ( j=0; j<nz; j++ ) rtmp[ajtmp[j]] = 0.0;
2296 
2297     /* load in initial (unfactored row) */
2298     nz       = ai[r[i]+1] - ai[r[i]];
2299     ajtmpold = aj + ai[r[i]];
2300     v        = aa + ai[r[i]];
2301     for ( j=0; j<nz; j++ ) rtmp[ic[ajtmpold[j]]] =  v[j];
2302 
2303     row = *ajtmp++;
2304     while (row < i) {
2305       pc = rtmp + row;
2306       if (*pc != 0.0) {
2307         pv         = ba + diag_offset[row];
2308         pj         = bj + diag_offset[row] + 1;
2309         multiplier = *pc * *pv++;
2310         *pc        = multiplier;
2311         nz         = bi[row+1] - diag_offset[row] - 1;
2312         for (j=0; j<nz; j++) rtmp[pj[j]] -= multiplier * pv[j];
2313         PLogFlops(1+2*nz);
2314       }
2315       row = *ajtmp++;
2316     }
2317     /* finished row so stick it into b->a */
2318     pv = ba + bi[i];
2319     pj = bj + bi[i];
2320     nz = bi[i+1] - bi[i];
2321     for ( j=0; j<nz; j++ ) {pv[j] = rtmp[pj[j]];}
2322     diag = diag_offset[i] - bi[i];
2323     /* check pivot entry for current row */
2324     if (pv[diag] == 0.0) {
2325       SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,0,"Zero pivot");
2326     }
2327     pv[diag] = 1.0/pv[diag];
2328   }
2329 
2330   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2331   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
2332   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
2333   C->factor    = FACTOR_LU;
2334   C->assembled = PETSC_TRUE;
2335   PLogFlops(b->n);
2336   PetscFunctionReturn(0);
2337 }
2338 
2339 /* ----------------------------------------------------------- */
2340 #undef __FUNC__
2341 #define __FUNC__ "MatLUFactor_SeqBAIJ"
2342 int MatLUFactor_SeqBAIJ(Mat A,IS row,IS col,double f)
2343 {
2344   Mat_SeqBAIJ    *mat = (Mat_SeqBAIJ *) A->data;
2345   int            ierr;
2346   Mat            C;
2347   PetscOps *Abops;
2348   MatOps   Aops;
2349 
2350   PetscFunctionBegin;
2351   ierr = MatLUFactorSymbolic(A,row,col,f,&C);CHKERRQ(ierr);
2352   ierr = MatLUFactorNumeric(A,&C);CHKERRQ(ierr);
2353 
2354   /* free all the data structures from mat */
2355   ierr = PetscFree(mat->a);CHKERRQ(ierr);
2356   if (!mat->singlemalloc) {
2357     ierr = PetscFree(mat->i);CHKERRQ(ierr);
2358     ierr = PetscFree(mat->j);CHKERRQ(ierr);
2359   }
2360   if (mat->diag) {ierr = PetscFree(mat->diag);CHKERRQ(ierr);}
2361   if (mat->ilen) {ierr = PetscFree(mat->ilen);CHKERRQ(ierr);}
2362   if (mat->imax) {ierr = PetscFree(mat->imax);CHKERRQ(ierr);}
2363   if (mat->solve_work) {ierr = PetscFree(mat->solve_work);CHKERRQ(ierr);}
2364   if (mat->mult_work) {ierr = PetscFree(mat->mult_work);CHKERRQ(ierr);}
2365   if (mat->icol) {ierr = ISDestroy(mat->icol);CHKERRQ(ierr);}
2366   ierr = PetscFree(mat);CHKERRQ(ierr);
2367 
2368   ierr = MapDestroy(A->rmap);CHKERRQ(ierr);
2369   ierr = MapDestroy(A->cmap);CHKERRQ(ierr);
2370 
2371   /*
2372        This is horrible, horrible code. We need to keep the
2373     A pointers for the bops and ops but copy everything
2374     else from C.
2375   */
2376   Abops = A->bops;
2377   Aops  = A->ops;
2378   ierr  = PetscMemcpy(A,C,sizeof(struct _p_Mat));CHKERRQ(ierr);
2379   mat   = (Mat_SeqBAIJ *) A->data;
2380   PLogObjectParent(A,mat->icol);
2381 
2382   A->bops  = Abops;
2383   A->ops   = Aops;
2384   A->qlist = 0;
2385 
2386   PetscHeaderDestroy(C);
2387   PetscFunctionReturn(0);
2388 }
2389 
2390 
2391 
2392