xref: /petsc/src/mat/impls/baij/seq/baijfact.c (revision 4da77479a31d4174cbdddbb52d31fbfbd1ffb3e6)
1 /*$Id: baijfact.c,v 1.79 2000/02/02 20:09:09 bsmith 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   if (A->M != A->N) SETERRQ(PETSC_ERR_ARG_WRONG,0,"matrix must be square");
28 
29   if (!isrow) {
30     ierr = ISCreateStride(PETSC_COMM_SELF,A->M,0,1,&isrow);CHKERRQ(ierr);
31   }
32   if (!iscol) {
33     ierr = ISCreateStride(PETSC_COMM_SELF,A->M,0,1,&iscol);CHKERRQ(ierr);
34   }
35   ierr = ISInvertPermutation(iscol,PETSC_DECIDE,&isicol);CHKERRQ(ierr);
36   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
37   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
38 
39   /* get new row pointers */
40   ainew = (int*)PetscMalloc((n+1)*sizeof(int));CHKPTRQ(ainew);
41   ainew[0] = 0;
42   /* don't know how many column pointers are needed so estimate */
43   jmax = (int)(f*ai[n] + 1);
44   ajnew = (int*)PetscMalloc((jmax)*sizeof(int));CHKPTRQ(ajnew);
45   /* fill is a linked list of nonzeros in active row */
46   fill = (int*)PetscMalloc((2*n+1)*sizeof(int));CHKPTRQ(fill);
47   im = fill + n + 1;
48   /* idnew is location of diagonal in factor */
49   idnew = (int*)PetscMalloc((n+1)*sizeof(int));CHKPTRQ(idnew);
50   idnew[0] = 0;
51 
52   for (i=0; i<n; i++) {
53     /* first copy previous fill into linked list */
54     nnz     = nz    = ai[r[i]+1] - ai[r[i]];
55     if (!nz) SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,1,"Empty row in matrix");
56     ajtmp   = aj + ai[r[i]];
57     fill[n] = n;
58     while (nz--) {
59       fm  = n;
60       idx = ic[*ajtmp++];
61       do {
62         m  = fm;
63         fm = fill[m];
64       } while (fm < idx);
65       fill[m]   = idx;
66       fill[idx] = fm;
67     }
68     row = fill[n];
69     while (row < i) {
70       ajtmp = ajnew + idnew[row] + 1;
71       nzbd  = 1 + idnew[row] - ainew[row];
72       nz    = im[row] - nzbd;
73       fm    = row;
74       while (nz-- > 0) {
75         idx = *ajtmp++;
76         nzbd++;
77         if (idx == i) im[row] = nzbd;
78         do {
79           m  = fm;
80           fm = fill[m];
81         } while (fm < idx);
82         if (fm != idx) {
83           fill[m]   = idx;
84           fill[idx] = fm;
85           fm        = idx;
86           nnz++;
87         }
88       }
89       row = fill[row];
90     }
91     /* copy new filled row into permanent storage */
92     ainew[i+1] = ainew[i] + nnz;
93     if (ainew[i+1] > jmax) {
94 
95       /* estimate how much additional space we will need */
96       /* use the strategy suggested by David Hysom <hysom@perch-t.icase.edu> */
97       /* just double the memory each time */
98       int maxadd = jmax;
99       /* maxadd = (int)((f*(ai[n]+1)*(n-i+5))/n); */
100       if (maxadd < nnz) maxadd = (n-i)*(nnz+1);
101       jmax += maxadd;
102 
103       /* allocate a longer ajnew */
104       ajtmp = (int*)PetscMalloc(jmax*sizeof(int));CHKPTRQ(ajtmp);
105       ierr  = PetscMemcpy(ajtmp,ajnew,ainew[i]*sizeof(int));CHKERRQ(ierr);
106       ierr = PetscFree(ajnew);CHKERRQ(ierr);
107       ajnew = ajtmp;
108       realloc++; /* count how many times we realloc */
109     }
110     ajtmp = ajnew + ainew[i];
111     fm    = fill[n];
112     nzi   = 0;
113     im[i] = nnz;
114     while (nnz--) {
115       if (fm < i) nzi++;
116       *ajtmp++ = fm;
117       fm       = fill[fm];
118     }
119     idnew[i] = ainew[i] + nzi;
120   }
121 
122   if (ai[n] != 0) {
123     PetscReal af = ((PetscReal)ainew[n])/((PetscReal)ai[n]);
124     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Reallocs %d Fill ratio:given %g needed %g\n",realloc,f,af);
125     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Run with -pc_lu_fill %g or use \n",af);
126     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:PCLUSetFill(pc,%g);\n",af);
127     PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:for best performance.\n");
128   } else {
129      PLogInfo(A,"MatLUFactorSymbolic_SeqBAIJ:Empty matrix.\n");
130   }
131 
132   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
133   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
134 
135   ierr = PetscFree(fill);CHKERRQ(ierr);
136 
137   /* put together the new matrix */
138   ierr = MatCreateSeqBAIJ(A->comm,bs,bs*n,bs*n,0,PETSC_NULL,B);CHKERRQ(ierr);
139   PLogObjectParent(*B,isicol);
140   b = (Mat_SeqBAIJ*)(*B)->data;
141   ierr = PetscFree(b->imax);CHKERRQ(ierr);
142   b->singlemalloc = PETSC_FALSE;
143   /* the next line frees the default space generated by the Create() */
144   ierr = PetscFree(b->a);CHKERRQ(ierr);
145   ierr = PetscFree(b->ilen);CHKERRQ(ierr);
146   b->a          = (MatScalar*)PetscMalloc((ainew[n]+1)*sizeof(MatScalar)*bs2);CHKPTRQ(b->a);
147   b->j          = ajnew;
148   b->i          = ainew;
149   b->diag       = idnew;
150   b->ilen       = 0;
151   b->imax       = 0;
152   b->row        = isrow;
153   b->col        = iscol;
154   ierr          = PetscObjectReference((PetscObject)isrow);CHKERRQ(ierr);
155   ierr          = PetscObjectReference((PetscObject)iscol);CHKERRQ(ierr);
156   b->icol       = isicol;
157   b->solve_work = (Scalar*)PetscMalloc((bs*n+bs)*sizeof(Scalar));CHKPTRQ(b->solve_work);
158   /* In b structure:  Free imax, ilen, old a, old j.
159      Allocate idnew, solve_work, new a, new j */
160   PLogObjectMemory(*B,(ainew[n]-n)*(sizeof(int)+sizeof(MatScalar)));
161   b->maxnz = b->nz = ainew[n];
162 
163   (*B)->factor                 = FACTOR_LU;
164   (*B)->info.factor_mallocs    = realloc;
165   (*B)->info.fill_ratio_given  = f;
166   if (ai[n] != 0) {
167     (*B)->info.fill_ratio_needed = ((PetscReal)ainew[n])/((PetscReal)ai[n]);
168   } else {
169     (*B)->info.fill_ratio_needed = 0.0;
170   }
171 
172 
173   PetscFunctionReturn(0);
174 }
175 
176 /* ----------------------------------------------------------- */
177 #undef __FUNC__
178 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_N"
179 int MatLUFactorNumeric_SeqBAIJ_N(Mat A,Mat *B)
180 {
181   Mat                C = *B;
182   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
183   IS                 isrow = b->row,isicol = b->icol;
184   int                *r,*ic,ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
185   int                *ajtmpold,*ajtmp,nz,row,bslog,*ai=a->i,*aj=a->j,k,flg;
186   int                *diag_offset=b->diag,diag,bs=a->bs,bs2 = a->bs2,*v_pivots,*pj;
187   MatScalar          *ba = b->a,*aa = a->a,*pv,*v,*rtmp,*multiplier,*v_work,*pc,*w;
188 
189   PetscFunctionBegin;
190   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
191   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
192   rtmp = (MatScalar*)PetscMalloc(bs2*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
193   ierr = PetscMemzero(rtmp,bs2*(n+1)*sizeof(MatScalar));CHKERRQ(ierr);
194   /* generate work space needed by dense LU factorization */
195   v_work     = (MatScalar*)PetscMalloc(bs*sizeof(int) + (bs+bs2)*sizeof(MatScalar));CHKPTRQ(v_work);
196   multiplier = v_work + bs;
197   v_pivots   = (int*)(multiplier + bs2);
198 
199   /* flops in while loop */
200   bslog = 2*bs*bs2;
201 
202   for (i=0; i<n; i++) {
203     nz    = bi[i+1] - bi[i];
204     ajtmp = bj + bi[i];
205     for  (j=0; j<nz; j++) {
206       ierr = PetscMemzero(rtmp+bs2*ajtmp[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
207     }
208     /* load in initial (unfactored row) */
209     nz       = ai[r[i]+1] - ai[r[i]];
210     ajtmpold = aj + ai[r[i]];
211     v        = aa + bs2*ai[r[i]];
212     for (j=0; j<nz; j++) {
213       ierr = PetscMemcpy(rtmp+bs2*ic[ajtmpold[j]],v+bs2*j,bs2*sizeof(MatScalar));CHKERRQ(ierr);
214     }
215     row = *ajtmp++;
216     while (row < i) {
217       pc = rtmp + bs2*row;
218 /*      if (*pc) { */
219       for (flg=0,k=0; k<bs2; k++) { if (pc[k]!=0.0) { flg =1; break; }}
220       if (flg) {
221         pv = ba + bs2*diag_offset[row];
222         pj = bj + diag_offset[row] + 1;
223         Kernel_A_gets_A_times_B(bs,pc,pv,multiplier);
224         nz = bi[row+1] - diag_offset[row] - 1;
225         pv += bs2;
226         for (j=0; j<nz; j++) {
227           Kernel_A_gets_A_minus_B_times_C(bs,rtmp+bs2*pj[j],pc,pv+bs2*j);
228         }
229         PLogFlops(bslog*(nz+1)-bs);
230       }
231         row = *ajtmp++;
232     }
233     /* finished row so stick it into b->a */
234     pv = ba + bs2*bi[i];
235     pj = bj + bi[i];
236     nz = bi[i+1] - bi[i];
237     for (j=0; j<nz; j++) {
238       ierr = PetscMemcpy(pv+bs2*j,rtmp+bs2*pj[j],bs2*sizeof(MatScalar));CHKERRQ(ierr);
239     }
240     diag = diag_offset[i] - bi[i];
241     /* invert diagonal block */
242     w = pv + bs2*diag;
243     Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);
244   }
245 
246   ierr = PetscFree(rtmp);CHKERRQ(ierr);
247   ierr = PetscFree(v_work);CHKERRQ(ierr);
248   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
249   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
250   C->factor = FACTOR_LU;
251   C->assembled = PETSC_TRUE;
252   PLogFlops(1.3333*bs*bs2*b->mbs); /* from inverting diagonal blocks */
253   PetscFunctionReturn(0);
254 }
255 /* ------------------------------------------------------------*/
256 /*
257       Version for when blocks are 7 by 7
258 */
259 #undef __FUNC__
260 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7"
261 int MatLUFactorNumeric_SeqBAIJ_7(Mat A,Mat *B)
262 {
263   Mat         C = *B;
264   Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
265   IS          isrow = b->row,isicol = b->icol;
266   int         *r,*ic,ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
267   int         *ajtmpold,*ajtmp,nz,row;
268   int         *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j,*pj;
269   MatScalar   *pv,*v,*rtmp,*pc,*w,*x;
270   MatScalar   p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
271   MatScalar   p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
272   MatScalar   x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
273   MatScalar   p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
274   MatScalar   m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
275   MatScalar   p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
276   MatScalar   p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
277   MatScalar   x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
278   MatScalar   x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
279   MatScalar   m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
280   MatScalar   m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
281   MatScalar   *ba = b->a,*aa = a->a;
282 
283   PetscFunctionBegin;
284   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
285   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
286   rtmp  = (MatScalar*)PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
287 
288   for (i=0; i<n; i++) {
289     nz    = bi[i+1] - bi[i];
290     ajtmp = bj + bi[i];
291     for  (j=0; j<nz; j++) {
292       x = rtmp+49*ajtmp[j];
293       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
294       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
295       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
296       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
297       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
298       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
299     }
300     /* load in initial (unfactored row) */
301     idx      = r[i];
302     nz       = ai[idx+1] - ai[idx];
303     ajtmpold = aj + ai[idx];
304     v        = aa + 49*ai[idx];
305     for (j=0; j<nz; j++) {
306       x    = rtmp+49*ic[ajtmpold[j]];
307       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
308       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
309       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
310       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
311       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
312       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
313       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
314       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
315       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
316       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
317       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
318       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
319       x[48] = v[48];
320       v    += 49;
321     }
322     row = *ajtmp++;
323     while (row < i) {
324       pc  =  rtmp + 49*row;
325       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
326       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
327       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
328       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
329       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
330       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
331       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
332       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
333       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
334       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
335       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
336       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
337       p49 = pc[48];
338       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
339           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
340           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
341           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
342           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
343           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
344           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
345           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
346           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
347           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
348           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
349           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
350           p49 != 0.0) {
351         pv = ba + 49*diag_offset[row];
352         pj = bj + diag_offset[row] + 1;
353 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
354 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
355 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
356 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
357 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
358 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
359 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
360 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
361 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
362 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
363 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
364 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
365 	x49 = pv[48];
366         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
367         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
368         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
369         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
370         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
371         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
372         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
373 
374         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
375         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
376         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
377         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
378         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
379         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
380         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
381 
382         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
383         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
384         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
385         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
386         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
387         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
388         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
389 
390         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
391         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
392         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
393         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
394         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
395         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
396         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
397 
398         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
399         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
400         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
401         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
402         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
403         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
404         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
405 
406         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
407         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
408         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
409         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
410         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
411         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
412         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
413 
414         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
415         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
416         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
417         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
418         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
419         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
420         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
421 
422         nz = bi[row+1] - diag_offset[row] - 1;
423         pv += 49;
424         for (j=0; j<nz; j++) {
425 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
426 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
427 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
428 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
429 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
430 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
431 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
432 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
433 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
434 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
435 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
436 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
437 	  x49 = pv[48];
438 	  x    = rtmp + 49*pj[j];
439 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
440 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
441 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
442 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
443 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
444 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
445 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
446 
447 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
448 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
449 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
450 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
451 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
452 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
453 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
454 
455 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
456 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
457 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
458 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
459 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
460 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
461 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
462 
463 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
464 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
465 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
466 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
467 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
468 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
469 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
470 
471 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
472 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
473 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
474 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
475 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
476 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
477 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
478 
479 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
480 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
481 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
482 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
483 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
484 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
485 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
486 
487 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
488 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
489 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
490 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
491 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
492 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
493 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
494           pv   += 49;
495         }
496         PLogFlops(686*nz+637);
497       }
498       row = *ajtmp++;
499     }
500     /* finished row so stick it into b->a */
501     pv = ba + 49*bi[i];
502     pj = bj + bi[i];
503     nz = bi[i+1] - bi[i];
504     for (j=0; j<nz; j++) {
505       x      = rtmp+49*pj[j];
506       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
507       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
508       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
509       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
510       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
511       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
512       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
513       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
514       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
515       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
516       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
517       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
518       pv[48] = x[48];
519       pv   += 49;
520     }
521     /* invert diagonal block */
522     w = ba + 49*diag_offset[i];
523     ierr = Kernel_A_gets_inverse_A_7(w);CHKERRQ(ierr);
524   }
525 
526   ierr = PetscFree(rtmp);CHKERRQ(ierr);
527   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
528   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
529   C->factor = FACTOR_LU;
530   C->assembled = PETSC_TRUE;
531   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
532   PetscFunctionReturn(0);
533 }
534 
535 /*
536       Version for when blocks are 7 by 7 Using natural ordering
537 */
538 #undef __FUNC__
539 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering"
540 int MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering(Mat A,Mat *B)
541 {
542   Mat          C = *B;
543   Mat_SeqBAIJ  *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
544   int          ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
545   int          *ajtmpold,*ajtmp,nz,row;
546   int          *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
547   MatScalar    *pv,*v,*rtmp,*pc,*w,*x;
548   MatScalar    x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
549   MatScalar    x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
550   MatScalar    p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
551   MatScalar    p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
552   MatScalar    m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
553   MatScalar    m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
554   MatScalar    p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
555   MatScalar    p37,p38,p39,p40,p41,p42,p43,p44,p45,p46,p47,p48,p49;
556   MatScalar    x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
557   MatScalar    x37,x38,x39,x40,x41,x42,x43,x44,x45,x46,x47,x48,x49;
558   MatScalar    m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
559   MatScalar    m37,m38,m39,m40,m41,m42,m43,m44,m45,m46,m47,m48,m49;
560   MatScalar    *ba = b->a,*aa = a->a;
561 
562   PetscFunctionBegin;
563   rtmp  = (MatScalar*)PetscMalloc(49*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
564   for (i=0; i<n; i++) {
565     nz    = bi[i+1] - bi[i];
566     ajtmp = bj + bi[i];
567     for  (j=0; j<nz; j++) {
568       x = rtmp+49*ajtmp[j];
569       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
570       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
571       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
572       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
573       x[34] = x[35] = x[36] = x[37] = x[38] = x[39] = x[40] = x[41] = 0.0 ;
574       x[42] = x[43] = x[44] = x[45] = x[46] = x[47] = x[48] = 0.0 ;
575     }
576     /* load in initial (unfactored row) */
577     nz       = ai[i+1] - ai[i];
578     ajtmpold = aj + ai[i];
579     v        = aa + 49*ai[i];
580     for (j=0; j<nz; j++) {
581       x    = rtmp+49*ajtmpold[j];
582       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
583       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
584       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
585       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
586       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
587       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
588       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
589       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
590       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
591       x[36] = v[36]; x[37] = v[37]; x[38] = v[38]; x[39] = v[39];
592       x[40] = v[40]; x[41] = v[41]; x[42] = v[42]; x[43] = v[43];
593       x[44] = v[44]; x[45] = v[45]; x[46] = v[46]; x[47] = v[47];
594       x[48] = v[48];
595       v    += 49;
596     }
597     row = *ajtmp++;
598     while (row < i) {
599       pc  = rtmp + 49*row;
600       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
601       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
602       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
603       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
604       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
605       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
606       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
607       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
608       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
609       p37 = pc[36]; p38 = pc[37]; p39 = pc[38]; p40 = pc[39];
610       p41 = pc[40]; p42 = pc[41]; p43 = pc[42]; p44 = pc[43];
611       p45 = pc[44]; p46 = pc[45]; p47 = pc[46]; p48 = pc[47];
612       p49 = pc[48];
613       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
614           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
615           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
616           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
617           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
618           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
619           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
620           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
621           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0 ||
622           p37 != 0.0 || p38 != 0.0 || p39 != 0.0 || p40 != 0.0 ||
623           p41 != 0.0 || p42 != 0.0 || p43 != 0.0 || p44 != 0.0 ||
624           p45 != 0.0 || p46 != 0.0 || p47 != 0.0 || p48 != 0.0 ||
625           p49 != 0.0) {
626         pv = ba + 49*diag_offset[row];
627         pj = bj + diag_offset[row] + 1;
628 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
629 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
630 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
631 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
632 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
633 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
634 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
635 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
636 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
637 	x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
638 	x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
639 	x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
640         x49 = pv[48];
641         pc[0]  = m1  = p1*x1  + p8*x2   + p15*x3  + p22*x4  + p29*x5  + p36*x6 + p43*x7;
642         pc[1]  = m2  = p2*x1  + p9*x2   + p16*x3  + p23*x4  + p30*x5  + p37*x6 + p44*x7;
643         pc[2]  = m3  = p3*x1  + p10*x2  + p17*x3  + p24*x4  + p31*x5  + p38*x6 + p45*x7;
644         pc[3]  = m4  = p4*x1  + p11*x2  + p18*x3  + p25*x4  + p32*x5  + p39*x6 + p46*x7;
645         pc[4]  = m5  = p5*x1  + p12*x2  + p19*x3  + p26*x4  + p33*x5  + p40*x6 + p47*x7;
646         pc[5]  = m6  = p6*x1  + p13*x2  + p20*x3  + p27*x4  + p34*x5  + p41*x6 + p48*x7;
647         pc[6]  = m7  = p7*x1  + p14*x2  + p21*x3  + p28*x4  + p35*x5  + p42*x6 + p49*x7;
648 
649         pc[7]  = m8  = p1*x8  + p8*x9   + p15*x10 + p22*x11 + p29*x12 + p36*x13 + p43*x14;
650         pc[8]  = m9  = p2*x8  + p9*x9   + p16*x10 + p23*x11 + p30*x12 + p37*x13 + p44*x14;
651         pc[9]  = m10 = p3*x8  + p10*x9  + p17*x10 + p24*x11 + p31*x12 + p38*x13 + p45*x14;
652         pc[10] = m11 = p4*x8  + p11*x9  + p18*x10 + p25*x11 + p32*x12 + p39*x13 + p46*x14;
653         pc[11] = m12 = p5*x8  + p12*x9  + p19*x10 + p26*x11 + p33*x12 + p40*x13 + p47*x14;
654         pc[12] = m13 = p6*x8  + p13*x9  + p20*x10 + p27*x11 + p34*x12 + p41*x13 + p48*x14;
655         pc[13] = m14 = p7*x8  + p14*x9  + p21*x10 + p28*x11 + p35*x12 + p42*x13 + p49*x14;
656 
657         pc[14] = m15 = p1*x15 + p8*x16  + p15*x17 + p22*x18 + p29*x19 + p36*x20 + p43*x21;
658         pc[15] = m16 = p2*x15 + p9*x16  + p16*x17 + p23*x18 + p30*x19 + p37*x20 + p44*x21;
659         pc[16] = m17 = p3*x15 + p10*x16 + p17*x17 + p24*x18 + p31*x19 + p38*x20 + p45*x21;
660         pc[17] = m18 = p4*x15 + p11*x16 + p18*x17 + p25*x18 + p32*x19 + p39*x20 + p46*x21;
661         pc[18] = m19 = p5*x15 + p12*x16 + p19*x17 + p26*x18 + p33*x19 + p40*x20 + p47*x21;
662         pc[19] = m20 = p6*x15 + p13*x16 + p20*x17 + p27*x18 + p34*x19 + p41*x20 + p48*x21;
663         pc[20] = m21 = p7*x15 + p14*x16 + p21*x17 + p28*x18 + p35*x19 + p42*x20 + p49*x21;
664 
665         pc[21] = m22 = p1*x22 + p8*x23  + p15*x24 + p22*x25 + p29*x26 + p36*x27 + p43*x28;
666         pc[22] = m23 = p2*x22 + p9*x23  + p16*x24 + p23*x25 + p30*x26 + p37*x27 + p44*x28;
667         pc[23] = m24 = p3*x22 + p10*x23 + p17*x24 + p24*x25 + p31*x26 + p38*x27 + p45*x28;
668         pc[24] = m25 = p4*x22 + p11*x23 + p18*x24 + p25*x25 + p32*x26 + p39*x27 + p46*x28;
669         pc[25] = m26 = p5*x22 + p12*x23 + p19*x24 + p26*x25 + p33*x26 + p40*x27 + p47*x28;
670         pc[26] = m27 = p6*x22 + p13*x23 + p20*x24 + p27*x25 + p34*x26 + p41*x27 + p48*x28;
671         pc[27] = m28 = p7*x22 + p14*x23 + p21*x24 + p28*x25 + p35*x26 + p42*x27 + p49*x28;
672 
673         pc[28] = m29 = p1*x29 + p8*x30  + p15*x31 + p22*x32 + p29*x33 + p36*x34 + p43*x35;
674         pc[29] = m30 = p2*x29 + p9*x30  + p16*x31 + p23*x32 + p30*x33 + p37*x34 + p44*x35;
675         pc[30] = m31 = p3*x29 + p10*x30 + p17*x31 + p24*x32 + p31*x33 + p38*x34 + p45*x35;
676         pc[31] = m32 = p4*x29 + p11*x30 + p18*x31 + p25*x32 + p32*x33 + p39*x34 + p46*x35;
677         pc[32] = m33 = p5*x29 + p12*x30 + p19*x31 + p26*x32 + p33*x33 + p40*x34 + p47*x35;
678         pc[33] = m34 = p6*x29 + p13*x30 + p20*x31 + p27*x32 + p34*x33 + p41*x34 + p48*x35;
679         pc[34] = m35 = p7*x29 + p14*x30 + p21*x31 + p28*x32 + p35*x33 + p42*x34 + p49*x35;
680 
681         pc[35] = m36 = p1*x36 + p8*x37  + p15*x38 + p22*x39 + p29*x40 + p36*x41 + p43*x42;
682         pc[36] = m37 = p2*x36 + p9*x37  + p16*x38 + p23*x39 + p30*x40 + p37*x41 + p44*x42;
683         pc[37] = m38 = p3*x36 + p10*x37 + p17*x38 + p24*x39 + p31*x40 + p38*x41 + p45*x42;
684         pc[38] = m39 = p4*x36 + p11*x37 + p18*x38 + p25*x39 + p32*x40 + p39*x41 + p46*x42;
685         pc[39] = m40 = p5*x36 + p12*x37 + p19*x38 + p26*x39 + p33*x40 + p40*x41 + p47*x42;
686         pc[40] = m41 = p6*x36 + p13*x37 + p20*x38 + p27*x39 + p34*x40 + p41*x41 + p48*x42;
687         pc[41] = m42 = p7*x36 + p14*x37 + p21*x38 + p28*x39 + p35*x40 + p42*x41 + p49*x42;
688 
689         pc[42] = m43 = p1*x43 + p8*x44  + p15*x45 + p22*x46 + p29*x47 + p36*x48 + p43*x49;
690         pc[43] = m44 = p2*x43 + p9*x44  + p16*x45 + p23*x46 + p30*x47 + p37*x48 + p44*x49;
691         pc[44] = m45 = p3*x43 + p10*x44 + p17*x45 + p24*x46 + p31*x47 + p38*x48 + p45*x49;
692         pc[45] = m46 = p4*x43 + p11*x44 + p18*x45 + p25*x46 + p32*x47 + p39*x48 + p46*x49;
693         pc[46] = m47 = p5*x43 + p12*x44 + p19*x45 + p26*x46 + p33*x47 + p40*x48 + p47*x49;
694         pc[47] = m48 = p6*x43 + p13*x44 + p20*x45 + p27*x46 + p34*x47 + p41*x48 + p48*x49;
695         pc[48] = m49 = p7*x43 + p14*x44 + p21*x45 + p28*x46 + p35*x47 + p42*x48 + p49*x49;
696 
697         nz = bi[row+1] - diag_offset[row] - 1;
698         pv += 49;
699         for (j=0; j<nz; j++) {
700 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
701 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
702 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
703 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
704 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
705 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
706 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
707 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
708 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
709 	  x37 = pv[36]; x38 = pv[37]; x39 = pv[38]; x40 = pv[39];
710 	  x41 = pv[40]; x42 = pv[41]; x43 = pv[42]; x44 = pv[43];
711 	  x45 = pv[44]; x46 = pv[45]; x47 = pv[46]; x48 = pv[47];
712 	  x49 = pv[48];
713 	  x    = rtmp + 49*pj[j];
714 	  x[0]  -= m1*x1  + m8*x2   + m15*x3  + m22*x4  + m29*x5  + m36*x6 + m43*x7;
715 	  x[1]  -= m2*x1  + m9*x2   + m16*x3  + m23*x4  + m30*x5  + m37*x6 + m44*x7;
716 	  x[2]  -= m3*x1  + m10*x2  + m17*x3  + m24*x4  + m31*x5  + m38*x6 + m45*x7;
717 	  x[3]  -= m4*x1  + m11*x2  + m18*x3  + m25*x4  + m32*x5  + m39*x6 + m46*x7;
718 	  x[4]  -= m5*x1  + m12*x2  + m19*x3  + m26*x4  + m33*x5  + m40*x6 + m47*x7;
719 	  x[5]  -= m6*x1  + m13*x2  + m20*x3  + m27*x4  + m34*x5  + m41*x6 + m48*x7;
720 	  x[6]  -= m7*x1  + m14*x2  + m21*x3  + m28*x4  + m35*x5  + m42*x6 + m49*x7;
721 
722 	  x[7]  -= m1*x8  + m8*x9   + m15*x10 + m22*x11 + m29*x12 + m36*x13 + m43*x14;
723 	  x[8]  -= m2*x8  + m9*x9   + m16*x10 + m23*x11 + m30*x12 + m37*x13 + m44*x14;
724 	  x[9]  -= m3*x8  + m10*x9  + m17*x10 + m24*x11 + m31*x12 + m38*x13 + m45*x14;
725 	  x[10] -= m4*x8  + m11*x9  + m18*x10 + m25*x11 + m32*x12 + m39*x13 + m46*x14;
726 	  x[11] -= m5*x8  + m12*x9  + m19*x10 + m26*x11 + m33*x12 + m40*x13 + m47*x14;
727 	  x[12] -= m6*x8  + m13*x9  + m20*x10 + m27*x11 + m34*x12 + m41*x13 + m48*x14;
728 	  x[13] -= m7*x8  + m14*x9  + m21*x10 + m28*x11 + m35*x12 + m42*x13 + m49*x14;
729 
730 	  x[14] -= m1*x15 + m8*x16  + m15*x17 + m22*x18 + m29*x19 + m36*x20 + m43*x21;
731 	  x[15] -= m2*x15 + m9*x16  + m16*x17 + m23*x18 + m30*x19 + m37*x20 + m44*x21;
732 	  x[16] -= m3*x15 + m10*x16 + m17*x17 + m24*x18 + m31*x19 + m38*x20 + m45*x21;
733 	  x[17] -= m4*x15 + m11*x16 + m18*x17 + m25*x18 + m32*x19 + m39*x20 + m46*x21;
734 	  x[18] -= m5*x15 + m12*x16 + m19*x17 + m26*x18 + m33*x19 + m40*x20 + m47*x21;
735 	  x[19] -= m6*x15 + m13*x16 + m20*x17 + m27*x18 + m34*x19 + m41*x20 + m48*x21;
736 	  x[20] -= m7*x15 + m14*x16 + m21*x17 + m28*x18 + m35*x19 + m42*x20 + m49*x21;
737 
738 	  x[21] -= m1*x22 + m8*x23  + m15*x24 + m22*x25 + m29*x26 + m36*x27 + m43*x28;
739 	  x[22] -= m2*x22 + m9*x23  + m16*x24 + m23*x25 + m30*x26 + m37*x27 + m44*x28;
740 	  x[23] -= m3*x22 + m10*x23 + m17*x24 + m24*x25 + m31*x26 + m38*x27 + m45*x28;
741 	  x[24] -= m4*x22 + m11*x23 + m18*x24 + m25*x25 + m32*x26 + m39*x27 + m46*x28;
742 	  x[25] -= m5*x22 + m12*x23 + m19*x24 + m26*x25 + m33*x26 + m40*x27 + m47*x28;
743 	  x[26] -= m6*x22 + m13*x23 + m20*x24 + m27*x25 + m34*x26 + m41*x27 + m48*x28;
744 	  x[27] -= m7*x22 + m14*x23 + m21*x24 + m28*x25 + m35*x26 + m42*x27 + m49*x28;
745 
746 	  x[28] -= m1*x29 + m8*x30  + m15*x31 + m22*x32 + m29*x33 + m36*x34 + m43*x35;
747 	  x[29] -= m2*x29 + m9*x30  + m16*x31 + m23*x32 + m30*x33 + m37*x34 + m44*x35;
748 	  x[30] -= m3*x29 + m10*x30 + m17*x31 + m24*x32 + m31*x33 + m38*x34 + m45*x35;
749 	  x[31] -= m4*x29 + m11*x30 + m18*x31 + m25*x32 + m32*x33 + m39*x34 + m46*x35;
750 	  x[32] -= m5*x29 + m12*x30 + m19*x31 + m26*x32 + m33*x33 + m40*x34 + m47*x35;
751 	  x[33] -= m6*x29 + m13*x30 + m20*x31 + m27*x32 + m34*x33 + m41*x34 + m48*x35;
752 	  x[34] -= m7*x29 + m14*x30 + m21*x31 + m28*x32 + m35*x33 + m42*x34 + m49*x35;
753 
754 	  x[35] -= m1*x36 + m8*x37  + m15*x38 + m22*x39 + m29*x40 + m36*x41 + m43*x42;
755 	  x[36] -= m2*x36 + m9*x37  + m16*x38 + m23*x39 + m30*x40 + m37*x41 + m44*x42;
756 	  x[37] -= m3*x36 + m10*x37 + m17*x38 + m24*x39 + m31*x40 + m38*x41 + m45*x42;
757 	  x[38] -= m4*x36 + m11*x37 + m18*x38 + m25*x39 + m32*x40 + m39*x41 + m46*x42;
758 	  x[39] -= m5*x36 + m12*x37 + m19*x38 + m26*x39 + m33*x40 + m40*x41 + m47*x42;
759 	  x[40] -= m6*x36 + m13*x37 + m20*x38 + m27*x39 + m34*x40 + m41*x41 + m48*x42;
760 	  x[41] -= m7*x36 + m14*x37 + m21*x38 + m28*x39 + m35*x40 + m42*x41 + m49*x42;
761 
762 	  x[42] -= m1*x43 + m8*x44  + m15*x45 + m22*x46 + m29*x47 + m36*x48 + m43*x49;
763 	  x[43] -= m2*x43 + m9*x44  + m16*x45 + m23*x46 + m30*x47 + m37*x48 + m44*x49;
764 	  x[44] -= m3*x43 + m10*x44 + m17*x45 + m24*x46 + m31*x47 + m38*x48 + m45*x49;
765 	  x[45] -= m4*x43 + m11*x44 + m18*x45 + m25*x46 + m32*x47 + m39*x48 + m46*x49;
766 	  x[46] -= m5*x43 + m12*x44 + m19*x45 + m26*x46 + m33*x47 + m40*x48 + m47*x49;
767 	  x[47] -= m6*x43 + m13*x44 + m20*x45 + m27*x46 + m34*x47 + m41*x48 + m48*x49;
768 	  x[48] -= m7*x43 + m14*x44 + m21*x45 + m28*x46 + m35*x47 + m42*x48 + m49*x49;
769           pv   += 49;
770         }
771         PLogFlops(686*nz+637);
772       }
773       row = *ajtmp++;
774     }
775     /* finished row so stick it into b->a */
776     pv = ba + 49*bi[i];
777     pj = bj + bi[i];
778     nz = bi[i+1] - bi[i];
779     for (j=0; j<nz; j++) {
780       x      = rtmp+49*pj[j];
781       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
782       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
783       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
784       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
785       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
786       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
787       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
788       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
789       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
790       pv[36] = x[36]; pv[37] = x[37]; pv[38] = x[38]; pv[39] = x[39];
791       pv[40] = x[40]; pv[41] = x[41]; pv[42] = x[42]; pv[43] = x[43];
792       pv[44] = x[44]; pv[45] = x[45]; pv[46] = x[46]; pv[47] = x[47];
793       pv[48] = x[48];
794       pv   += 49;
795     }
796     /* invert diagonal block */
797     w = ba + 49*diag_offset[i];
798     ierr = Kernel_A_gets_inverse_A_7(w);CHKERRQ(ierr);
799   }
800 
801   ierr = PetscFree(rtmp);CHKERRQ(ierr);
802   C->factor    = FACTOR_LU;
803   C->assembled = PETSC_TRUE;
804   PLogFlops(1.3333*343*b->mbs); /* from inverting diagonal blocks */
805   PetscFunctionReturn(0);
806 }
807 
808 /* ------------------------------------------------------------*/
809 /*
810       Version for when blocks are 6 by 6
811 */
812 #undef __FUNC__
813 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6"
814 int MatLUFactorNumeric_SeqBAIJ_6(Mat A,Mat *B)
815 {
816   Mat          C = *B;
817   Mat_SeqBAIJ  *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
818   IS           isrow = b->row,isicol = b->icol;
819   int          *r,*ic,ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
820   int          *ajtmpold,*ajtmp,nz,row;
821   int          *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j,*pj;
822   MatScalar    *pv,*v,*rtmp,*pc,*w,*x;
823   MatScalar    p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
824   MatScalar    p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
825   MatScalar    x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
826   MatScalar    p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
827   MatScalar    m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
828   MatScalar    p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
829   MatScalar    x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
830   MatScalar    m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
831   MatScalar    *ba = b->a,*aa = a->a;
832 
833   PetscFunctionBegin;
834   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
835   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
836   rtmp  = (MatScalar*)PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
837 
838   for (i=0; i<n; i++) {
839     nz    = bi[i+1] - bi[i];
840     ajtmp = bj + bi[i];
841     for  (j=0; j<nz; j++) {
842       x = rtmp+36*ajtmp[j];
843       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
844       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
845       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
846       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
847       x[34] = x[35] = 0.0 ;
848     }
849     /* load in initial (unfactored row) */
850     idx      = r[i];
851     nz       = ai[idx+1] - ai[idx];
852     ajtmpold = aj + ai[idx];
853     v        = aa + 36*ai[idx];
854     for (j=0; j<nz; j++) {
855       x    = rtmp+36*ic[ajtmpold[j]];
856       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
857       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
858       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
859       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
860       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
861       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
862       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
863       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
864       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
865       v    += 36;
866     }
867     row = *ajtmp++;
868     while (row < i) {
869       pc  =  rtmp + 36*row;
870       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
871       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
872       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
873       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
874       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
875       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
876       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
877       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
878       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
879       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
880           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
881           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
882           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
883           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
884           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
885           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
886           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
887           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
888         pv = ba + 36*diag_offset[row];
889         pj = bj + diag_offset[row] + 1;
890 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
891 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
892 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
893 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
894 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
895 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
896 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
897 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
898 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
899         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
900         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
901         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
902         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
903         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
904         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
905 
906         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
907         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
908         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
909         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
910         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
911         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
912 
913         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
914         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
915         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
916         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
917         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
918         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
919 
920         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
921         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
922         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
923         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
924         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
925         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
926 
927         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
928         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
929         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
930         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
931         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
932         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
933 
934         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
935         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
936         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
937         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
938         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
939         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
940 
941         nz = bi[row+1] - diag_offset[row] - 1;
942         pv += 36;
943         for (j=0; j<nz; j++) {
944 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
945 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
946 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
947 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
948 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
949 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
950 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
951 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
952 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
953 	  x    = rtmp + 36*pj[j];
954           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
955           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
956           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
957           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
958           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
959           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
960 
961 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
962 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
963 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
964 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
965 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
966 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
967 
968 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
969 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
970 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
971 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
972 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
973 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
974 
975 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
976 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
977 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
978 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
979 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
980 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
981 
982 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
983 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
984 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
985 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
986 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
987 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
988 
989 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
990 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
991 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
992 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
993 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
994 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
995 
996           pv   += 36;
997         }
998         PLogFlops(432*nz+396);
999       }
1000       row = *ajtmp++;
1001     }
1002     /* finished row so stick it into b->a */
1003     pv = ba + 36*bi[i];
1004     pj = bj + bi[i];
1005     nz = bi[i+1] - bi[i];
1006     for (j=0; j<nz; j++) {
1007       x      = rtmp+36*pj[j];
1008       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1009       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1010       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1011       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1012       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1013       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1014       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1015       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1016       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1017       pv   += 36;
1018     }
1019     /* invert diagonal block */
1020     w = ba + 36*diag_offset[i];
1021     ierr = Kernel_A_gets_inverse_A_6(w);CHKERRQ(ierr);
1022   }
1023 
1024   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1025   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1026   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1027   C->factor = FACTOR_LU;
1028   C->assembled = PETSC_TRUE;
1029   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1030   PetscFunctionReturn(0);
1031 }
1032 /*
1033       Version for when blocks are 6 by 6 Using natural ordering
1034 */
1035 #undef __FUNC__
1036 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering"
1037 int MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering(Mat A,Mat *B)
1038 {
1039   Mat         C = *B;
1040   Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
1041   int         ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
1042   int         *ajtmpold,*ajtmp,nz,row;
1043   int         *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
1044   MatScalar   *pv,*v,*rtmp,*pc,*w,*x;
1045   MatScalar   x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1046   MatScalar   x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1047   MatScalar   p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1048   MatScalar   p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1049   MatScalar   m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1050   MatScalar   m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1051   MatScalar   p26,p27,p28,p29,p30,p31,p32,p33,p34,p35,p36;
1052   MatScalar   x26,x27,x28,x29,x30,x31,x32,x33,x34,x35,x36;
1053   MatScalar   m26,m27,m28,m29,m30,m31,m32,m33,m34,m35,m36;
1054   MatScalar   *ba = b->a,*aa = a->a;
1055 
1056   PetscFunctionBegin;
1057   rtmp  = (MatScalar*)PetscMalloc(36*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1058   for (i=0; i<n; i++) {
1059     nz    = bi[i+1] - bi[i];
1060     ajtmp = bj + bi[i];
1061     for  (j=0; j<nz; j++) {
1062       x = rtmp+36*ajtmp[j];
1063       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1064       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1065       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = x[25] = 0.0 ;
1066       x[26] = x[27] = x[28] = x[29] = x[30] = x[31] = x[32] = x[33] = 0.0 ;
1067       x[34] = x[35] = 0.0 ;
1068     }
1069     /* load in initial (unfactored row) */
1070     nz       = ai[i+1] - ai[i];
1071     ajtmpold = aj + ai[i];
1072     v        = aa + 36*ai[i];
1073     for (j=0; j<nz; j++) {
1074       x    = rtmp+36*ajtmpold[j];
1075       x[0] =  v[0];  x[1] =  v[1];  x[2] =  v[2];  x[3] =  v[3];
1076       x[4] =  v[4];  x[5] =  v[5];  x[6] =  v[6];  x[7] =  v[7];
1077       x[8] =  v[8];  x[9] =  v[9];  x[10] = v[10]; x[11] = v[11];
1078       x[12] = v[12]; x[13] = v[13]; x[14] = v[14]; x[15] = v[15];
1079       x[16] = v[16]; x[17] = v[17]; x[18] = v[18]; x[19] = v[19];
1080       x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1081       x[24] = v[24]; x[25] = v[25]; x[26] = v[26]; x[27] = v[27];
1082       x[28] = v[28]; x[29] = v[29]; x[30] = v[30]; x[31] = v[31];
1083       x[32] = v[32]; x[33] = v[33]; x[34] = v[34]; x[35] = v[35];
1084       v    += 36;
1085     }
1086     row = *ajtmp++;
1087     while (row < i) {
1088       pc  = rtmp + 36*row;
1089       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1090       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];
1091       p9  = pc[8];  p10 = pc[9];  p11 = pc[10]; p12 = pc[11];
1092       p13 = pc[12]; p14 = pc[13]; p15 = pc[14]; p16 = pc[15];
1093       p17 = pc[16]; p18 = pc[17]; p19 = pc[18]; p20 = pc[19];
1094       p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1095       p25 = pc[24]; p26 = pc[25]; p27 = pc[26]; p28 = pc[27];
1096       p29 = pc[28]; p30 = pc[29]; p31 = pc[30]; p32 = pc[31];
1097       p33 = pc[32]; p34 = pc[33]; p35 = pc[34]; p36 = pc[35];
1098       if (p1  != 0.0 || p2  != 0.0 || p3  != 0.0 || p4  != 0.0 ||
1099           p5  != 0.0 || p6  != 0.0 || p7  != 0.0 || p8  != 0.0 ||
1100           p9  != 0.0 || p10 != 0.0 || p11 != 0.0 || p12 != 0.0 ||
1101           p13 != 0.0 || p14 != 0.0 || p15 != 0.0 || p16 != 0.0 ||
1102           p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0 ||
1103           p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 ||
1104           p25 != 0.0 || p26 != 0.0 || p27 != 0.0 || p28 != 0.0 ||
1105           p29 != 0.0 || p30 != 0.0 || p31 != 0.0 || p32 != 0.0 ||
1106           p33 != 0.0 || p34 != 0.0 || p35 != 0.0 || p36 != 0.0) {
1107         pv = ba + 36*diag_offset[row];
1108         pj = bj + diag_offset[row] + 1;
1109 	x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1110 	x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1111 	x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1112 	x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1113 	x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1114 	x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1115 	x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1116 	x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1117 	x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1118         pc[0]  = m1  = p1*x1  + p7*x2   + p13*x3  + p19*x4  + p25*x5  + p31*x6;
1119         pc[1]  = m2  = p2*x1  + p8*x2   + p14*x3  + p20*x4  + p26*x5  + p32*x6;
1120         pc[2]  = m3  = p3*x1  + p9*x2   + p15*x3  + p21*x4  + p27*x5  + p33*x6;
1121         pc[3]  = m4  = p4*x1  + p10*x2  + p16*x3  + p22*x4  + p28*x5  + p34*x6;
1122         pc[4]  = m5  = p5*x1  + p11*x2  + p17*x3  + p23*x4  + p29*x5  + p35*x6;
1123         pc[5]  = m6  = p6*x1  + p12*x2  + p18*x3  + p24*x4  + p30*x5  + p36*x6;
1124 
1125         pc[6]  = m7  = p1*x7  + p7*x8   + p13*x9  + p19*x10 + p25*x11 + p31*x12;
1126         pc[7]  = m8  = p2*x7  + p8*x8   + p14*x9  + p20*x10 + p26*x11 + p32*x12;
1127         pc[8]  = m9  = p3*x7  + p9*x8   + p15*x9  + p21*x10 + p27*x11 + p33*x12;
1128         pc[9]  = m10 = p4*x7  + p10*x8  + p16*x9  + p22*x10 + p28*x11 + p34*x12;
1129         pc[10] = m11 = p5*x7  + p11*x8  + p17*x9  + p23*x10 + p29*x11 + p35*x12;
1130         pc[11] = m12 = p6*x7  + p12*x8  + p18*x9  + p24*x10 + p30*x11 + p36*x12;
1131 
1132         pc[12] = m13 = p1*x13 + p7*x14  + p13*x15 + p19*x16 + p25*x17 + p31*x18;
1133         pc[13] = m14 = p2*x13 + p8*x14  + p14*x15 + p20*x16 + p26*x17 + p32*x18;
1134         pc[14] = m15 = p3*x13 + p9*x14  + p15*x15 + p21*x16 + p27*x17 + p33*x18;
1135         pc[15] = m16 = p4*x13 + p10*x14 + p16*x15 + p22*x16 + p28*x17 + p34*x18;
1136         pc[16] = m17 = p5*x13 + p11*x14 + p17*x15 + p23*x16 + p29*x17 + p35*x18;
1137         pc[17] = m18 = p6*x13 + p12*x14 + p18*x15 + p24*x16 + p30*x17 + p36*x18;
1138 
1139         pc[18] = m19 = p1*x19 + p7*x20  + p13*x21 + p19*x22 + p25*x23 + p31*x24;
1140         pc[19] = m20 = p2*x19 + p8*x20  + p14*x21 + p20*x22 + p26*x23 + p32*x24;
1141         pc[20] = m21 = p3*x19 + p9*x20  + p15*x21 + p21*x22 + p27*x23 + p33*x24;
1142         pc[21] = m22 = p4*x19 + p10*x20 + p16*x21 + p22*x22 + p28*x23 + p34*x24;
1143         pc[22] = m23 = p5*x19 + p11*x20 + p17*x21 + p23*x22 + p29*x23 + p35*x24;
1144         pc[23] = m24 = p6*x19 + p12*x20 + p18*x21 + p24*x22 + p30*x23 + p36*x24;
1145 
1146         pc[24] = m25 = p1*x25 + p7*x26  + p13*x27 + p19*x28 + p25*x29 + p31*x30;
1147         pc[25] = m26 = p2*x25 + p8*x26  + p14*x27 + p20*x28 + p26*x29 + p32*x30;
1148         pc[26] = m27 = p3*x25 + p9*x26  + p15*x27 + p21*x28 + p27*x29 + p33*x30;
1149         pc[27] = m28 = p4*x25 + p10*x26 + p16*x27 + p22*x28 + p28*x29 + p34*x30;
1150         pc[28] = m29 = p5*x25 + p11*x26 + p17*x27 + p23*x28 + p29*x29 + p35*x30;
1151         pc[29] = m30 = p6*x25 + p12*x26 + p18*x27 + p24*x28 + p30*x29 + p36*x30;
1152 
1153         pc[30] = m31 = p1*x31 + p7*x32  + p13*x33 + p19*x34 + p25*x35 + p31*x36;
1154         pc[31] = m32 = p2*x31 + p8*x32  + p14*x33 + p20*x34 + p26*x35 + p32*x36;
1155         pc[32] = m33 = p3*x31 + p9*x32  + p15*x33 + p21*x34 + p27*x35 + p33*x36;
1156         pc[33] = m34 = p4*x31 + p10*x32 + p16*x33 + p22*x34 + p28*x35 + p34*x36;
1157         pc[34] = m35 = p5*x31 + p11*x32 + p17*x33 + p23*x34 + p29*x35 + p35*x36;
1158         pc[35] = m36 = p6*x31 + p12*x32 + p18*x33 + p24*x34 + p30*x35 + p36*x36;
1159 
1160         nz = bi[row+1] - diag_offset[row] - 1;
1161         pv += 36;
1162         for (j=0; j<nz; j++) {
1163 	  x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1164 	  x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];
1165 	  x9  = pv[8];  x10 = pv[9];  x11 = pv[10]; x12 = pv[11];
1166 	  x13 = pv[12]; x14 = pv[13]; x15 = pv[14]; x16 = pv[15];
1167 	  x17 = pv[16]; x18 = pv[17]; x19 = pv[18]; x20 = pv[19];
1168 	  x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1169 	  x25 = pv[24]; x26 = pv[25]; x27 = pv[26]; x28 = pv[27];
1170 	  x29 = pv[28]; x30 = pv[29]; x31 = pv[30]; x32 = pv[31];
1171 	  x33 = pv[32]; x34 = pv[33]; x35 = pv[34]; x36 = pv[35];
1172 	  x    = rtmp + 36*pj[j];
1173           x[0]  -= m1*x1  + m7*x2   + m13*x3  + m19*x4  + m25*x5  + m31*x6;
1174           x[1]  -= m2*x1  + m8*x2   + m14*x3  + m20*x4  + m26*x5  + m32*x6;
1175           x[2]  -= m3*x1  + m9*x2   + m15*x3  + m21*x4  + m27*x5  + m33*x6;
1176           x[3]  -= m4*x1  + m10*x2  + m16*x3  + m22*x4  + m28*x5  + m34*x6;
1177           x[4]  -= m5*x1  + m11*x2  + m17*x3  + m23*x4  + m29*x5  + m35*x6;
1178           x[5]  -= m6*x1  + m12*x2  + m18*x3  + m24*x4  + m30*x5  + m36*x6;
1179 
1180 	  x[6]  -= m1*x7  + m7*x8   + m13*x9  + m19*x10 + m25*x11 + m31*x12;
1181 	  x[7]  -= m2*x7  + m8*x8   + m14*x9  + m20*x10 + m26*x11 + m32*x12;
1182 	  x[8]  -= m3*x7  + m9*x8   + m15*x9  + m21*x10 + m27*x11 + m33*x12;
1183 	  x[9]  -= m4*x7  + m10*x8  + m16*x9  + m22*x10 + m28*x11 + m34*x12;
1184 	  x[10] -= m5*x7  + m11*x8  + m17*x9  + m23*x10 + m29*x11 + m35*x12;
1185 	  x[11] -= m6*x7  + m12*x8  + m18*x9  + m24*x10 + m30*x11 + m36*x12;
1186 
1187 	  x[12] -= m1*x13 + m7*x14  + m13*x15 + m19*x16 + m25*x17 + m31*x18;
1188 	  x[13] -= m2*x13 + m8*x14  + m14*x15 + m20*x16 + m26*x17 + m32*x18;
1189 	  x[14] -= m3*x13 + m9*x14  + m15*x15 + m21*x16 + m27*x17 + m33*x18;
1190 	  x[15] -= m4*x13 + m10*x14 + m16*x15 + m22*x16 + m28*x17 + m34*x18;
1191 	  x[16] -= m5*x13 + m11*x14 + m17*x15 + m23*x16 + m29*x17 + m35*x18;
1192 	  x[17] -= m6*x13 + m12*x14 + m18*x15 + m24*x16 + m30*x17 + m36*x18;
1193 
1194 	  x[18] -= m1*x19 + m7*x20  + m13*x21 + m19*x22 + m25*x23 + m31*x24;
1195 	  x[19] -= m2*x19 + m8*x20  + m14*x21 + m20*x22 + m26*x23 + m32*x24;
1196 	  x[20] -= m3*x19 + m9*x20  + m15*x21 + m21*x22 + m27*x23 + m33*x24;
1197 	  x[21] -= m4*x19 + m10*x20 + m16*x21 + m22*x22 + m28*x23 + m34*x24;
1198 	  x[22] -= m5*x19 + m11*x20 + m17*x21 + m23*x22 + m29*x23 + m35*x24;
1199 	  x[23] -= m6*x19 + m12*x20 + m18*x21 + m24*x22 + m30*x23 + m36*x24;
1200 
1201 	  x[24] -= m1*x25 + m7*x26  + m13*x27 + m19*x28 + m25*x29 + m31*x30;
1202 	  x[25] -= m2*x25 + m8*x26  + m14*x27 + m20*x28 + m26*x29 + m32*x30;
1203 	  x[26] -= m3*x25 + m9*x26  + m15*x27 + m21*x28 + m27*x29 + m33*x30;
1204 	  x[27] -= m4*x25 + m10*x26 + m16*x27 + m22*x28 + m28*x29 + m34*x30;
1205 	  x[28] -= m5*x25 + m11*x26 + m17*x27 + m23*x28 + m29*x29 + m35*x30;
1206 	  x[29] -= m6*x25 + m12*x26 + m18*x27 + m24*x28 + m30*x29 + m36*x30;
1207 
1208 	  x[30] -= m1*x31 + m7*x32  + m13*x33 + m19*x34 + m25*x35 + m31*x36;
1209 	  x[31] -= m2*x31 + m8*x32  + m14*x33 + m20*x34 + m26*x35 + m32*x36;
1210 	  x[32] -= m3*x31 + m9*x32  + m15*x33 + m21*x34 + m27*x35 + m33*x36;
1211 	  x[33] -= m4*x31 + m10*x32 + m16*x33 + m22*x34 + m28*x35 + m34*x36;
1212 	  x[34] -= m5*x31 + m11*x32 + m17*x33 + m23*x34 + m29*x35 + m35*x36;
1213 	  x[35] -= m6*x31 + m12*x32 + m18*x33 + m24*x34 + m30*x35 + m36*x36;
1214 
1215           pv   += 36;
1216         }
1217         PLogFlops(432*nz+396);
1218       }
1219       row = *ajtmp++;
1220     }
1221     /* finished row so stick it into b->a */
1222     pv = ba + 36*bi[i];
1223     pj = bj + bi[i];
1224     nz = bi[i+1] - bi[i];
1225     for (j=0; j<nz; j++) {
1226       x      = rtmp+36*pj[j];
1227       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1228       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7];
1229       pv[8]  = x[8];  pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11];
1230       pv[12] = x[12]; pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1231       pv[16] = x[16]; pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19];
1232       pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23];
1233       pv[24] = x[24]; pv[25] = x[25]; pv[26] = x[26]; pv[27] = x[27];
1234       pv[28] = x[28]; pv[29] = x[29]; pv[30] = x[30]; pv[31] = x[31];
1235       pv[32] = x[32]; pv[33] = x[33]; pv[34] = x[34]; pv[35] = x[35];
1236       pv   += 36;
1237     }
1238     /* invert diagonal block */
1239     w = ba + 36*diag_offset[i];
1240     ierr = Kernel_A_gets_inverse_A_6(w);CHKERRQ(ierr);
1241   }
1242 
1243   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1244   C->factor    = FACTOR_LU;
1245   C->assembled = PETSC_TRUE;
1246   PLogFlops(1.3333*216*b->mbs); /* from inverting diagonal blocks */
1247   PetscFunctionReturn(0);
1248 }
1249 
1250 /* ------------------------------------------------------------*/
1251 /*
1252       Version for when blocks are 5 by 5
1253 */
1254 #undef __FUNC__
1255 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5"
1256 int MatLUFactorNumeric_SeqBAIJ_5(Mat A,Mat *B)
1257 {
1258   Mat         C = *B;
1259   Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
1260   IS          isrow = b->row,isicol = b->icol;
1261   int         *r,*ic,ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
1262   int         *ajtmpold,*ajtmp,nz,row;
1263   int         *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j,*pj;
1264   MatScalar   *pv,*v,*rtmp,*pc,*w,*x;
1265   MatScalar   p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1266   MatScalar   p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1267   MatScalar   x17,x18,x19,x20,x21,x22,x23,x24,x25,p10,p11,p12,p13,p14;
1268   MatScalar   p15,p16,p17,p18,p19,p20,p21,p22,p23,p24,p25,m10,m11,m12;
1269   MatScalar   m13,m14,m15,m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1270   MatScalar   *ba = b->a,*aa = a->a;
1271 
1272   PetscFunctionBegin;
1273   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1274   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1275   rtmp  = (MatScalar*)PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1276 
1277   for (i=0; i<n; i++) {
1278     nz    = bi[i+1] - bi[i];
1279     ajtmp = bj + bi[i];
1280     for  (j=0; j<nz; j++) {
1281       x = rtmp+25*ajtmp[j];
1282       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = x[9] = 0.0;
1283       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = x[16] = x[17] = 0.0;
1284       x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1285     }
1286     /* load in initial (unfactored row) */
1287     idx      = r[i];
1288     nz       = ai[idx+1] - ai[idx];
1289     ajtmpold = aj + ai[idx];
1290     v        = aa + 25*ai[idx];
1291     for (j=0; j<nz; j++) {
1292       x    = rtmp+25*ic[ajtmpold[j]];
1293       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1294       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1295       x[9] = v[9]; x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1296       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17];
1297       x[18] = v[18]; x[19] = v[19]; x[20] = v[20]; x[21] = v[21];
1298       x[22] = v[22]; x[23] = v[23]; x[24] = v[24];
1299       v    += 25;
1300     }
1301     row = *ajtmp++;
1302     while (row < i) {
1303       pc = rtmp + 25*row;
1304       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1305       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1306       p10 = pc[9]; p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1307       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17]; p19 = pc[18];
1308       p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22]; p24 = pc[23];
1309       p25 = pc[24];
1310       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1311           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1312           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1313           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 ||
1314           p20 != 0.0 || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 ||
1315           p24 != 0.0 || p25 != 0.0) {
1316         pv = ba + 25*diag_offset[row];
1317         pj = bj + diag_offset[row] + 1;
1318         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1319         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1320         x10 = pv[9]; x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1321         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1322         x19 = pv[18]; x20 = pv[19]; x21 = pv[20]; x22 = pv[21];
1323         x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1324         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1325         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1326         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1327         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1328         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1329 
1330         pc[5] = m6 = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1331         pc[6] = m7 = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1332         pc[7] = m8 = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1333         pc[8] = m9 = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1334         pc[9] = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1335 
1336         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1337         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1338         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1339         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1340         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1341 
1342         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1343         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1344         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1345         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1346         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1347 
1348         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1349         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1350         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1351         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1352         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1353 
1354         nz = bi[row+1] - diag_offset[row] - 1;
1355         pv += 25;
1356         for (j=0; j<nz; j++) {
1357           x1   = pv[0];  x2 = pv[1];   x3  = pv[2];  x4  = pv[3];
1358           x5   = pv[4];  x6 = pv[5];   x7  = pv[6];  x8  = pv[7]; x9 = pv[8];
1359           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1360           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16];
1361           x18  = pv[17]; x19 = pv[18]; x20 = pv[19]; x21 = pv[20];
1362           x22  = pv[21]; x23 = pv[22]; x24 = pv[23]; x25 = pv[24];
1363           x    = rtmp + 25*pj[j];
1364           x[0] -= m1*x1 + m6*x2  + m11*x3 + m16*x4 + m21*x5;
1365           x[1] -= m2*x1 + m7*x2  + m12*x3 + m17*x4 + m22*x5;
1366           x[2] -= m3*x1 + m8*x2  + m13*x3 + m18*x4 + m23*x5;
1367           x[3] -= m4*x1 + m9*x2  + m14*x3 + m19*x4 + m24*x5;
1368           x[4] -= m5*x1 + m10*x2 + m15*x3 + m20*x4 + m25*x5;
1369 
1370           x[5] -= m1*x6 + m6*x7  + m11*x8 + m16*x9 + m21*x10;
1371           x[6] -= m2*x6 + m7*x7  + m12*x8 + m17*x9 + m22*x10;
1372           x[7] -= m3*x6 + m8*x7  + m13*x8 + m18*x9 + m23*x10;
1373           x[8] -= m4*x6 + m9*x7  + m14*x8 + m19*x9 + m24*x10;
1374           x[9] -= m5*x6 + m10*x7 + m15*x8 + m20*x9 + m25*x10;
1375 
1376           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1377           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1378           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1379           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1380           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1381 
1382           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1383           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1384           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1385           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1386           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1387 
1388           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1389           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1390           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1391           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1392           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1393 
1394           pv   += 25;
1395         }
1396         PLogFlops(250*nz+225);
1397       }
1398       row = *ajtmp++;
1399     }
1400     /* finished row so stick it into b->a */
1401     pv = ba + 25*bi[i];
1402     pj = bj + bi[i];
1403     nz = bi[i+1] - bi[i];
1404     for (j=0; j<nz; j++) {
1405       x     = rtmp+25*pj[j];
1406       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1407       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1408       pv[9] = x[9]; pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1409       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16];
1410       pv[17] = x[17]; pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20];
1411       pv[21] = x[21]; pv[22] = x[22]; pv[23] = x[23]; pv[24] = x[24];
1412       pv   += 25;
1413     }
1414     /* invert diagonal block */
1415     w = ba + 25*diag_offset[i];
1416     ierr = Kernel_A_gets_inverse_A_5(w);CHKERRQ(ierr);
1417   }
1418 
1419   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1420   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1421   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1422   C->factor = FACTOR_LU;
1423   C->assembled = PETSC_TRUE;
1424   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1425   PetscFunctionReturn(0);
1426 }
1427 /*
1428       Version for when blocks are 5 by 5 Using natural ordering
1429 */
1430 #undef __FUNC__
1431 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering"
1432 int MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering(Mat A,Mat *B)
1433 {
1434   Mat         C = *B;
1435   Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
1436   int         ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
1437   int         *ajtmpold,*ajtmp,nz,row;
1438   int         *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
1439   MatScalar   *pv,*v,*rtmp,*pc,*w,*x;
1440   MatScalar   x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
1441   MatScalar   x16,x17,x18,x19,x20,x21,x22,x23,x24,x25;
1442   MatScalar   p1,p2,p3,p4,p5,p6,p7,p8,p9,p10,p11,p12,p13,p14,p15;
1443   MatScalar   p16,p17,p18,p19,p20,p21,p22,p23,p24,p25;
1444   MatScalar   m1,m2,m3,m4,m5,m6,m7,m8,m9,m10,m11,m12,m13,m14,m15;
1445   MatScalar   m16,m17,m18,m19,m20,m21,m22,m23,m24,m25;
1446   MatScalar   *ba = b->a,*aa = a->a;
1447 
1448   PetscFunctionBegin;
1449   rtmp  = (MatScalar*)PetscMalloc(25*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1450   for (i=0; i<n; i++) {
1451     nz    = bi[i+1] - bi[i];
1452     ajtmp = bj + bi[i];
1453     for  (j=0; j<nz; j++) {
1454       x = rtmp+25*ajtmp[j];
1455       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1456       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1457       x[16] = x[17] = x[18] = x[19] = x[20] = x[21] = x[22] = x[23] = x[24] = 0.0;
1458     }
1459     /* load in initial (unfactored row) */
1460     nz       = ai[i+1] - ai[i];
1461     ajtmpold = aj + ai[i];
1462     v        = aa + 25*ai[i];
1463     for (j=0; j<nz; j++) {
1464       x    = rtmp+25*ajtmpold[j];
1465       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1466       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1467       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1468       x[14] = v[14]; x[15] = v[15]; x[16] = v[16]; x[17] = v[17]; x[18] = v[18];
1469       x[19] = v[19]; x[20] = v[20]; x[21] = v[21]; x[22] = v[22]; x[23] = v[23];
1470       x[24] = v[24];
1471       v    += 25;
1472     }
1473     row = *ajtmp++;
1474     while (row < i) {
1475       pc  = rtmp + 25*row;
1476       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1477       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1478       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1479       p15 = pc[14]; p16 = pc[15]; p17 = pc[16]; p18 = pc[17];
1480       p19 = pc[18]; p20 = pc[19]; p21 = pc[20]; p22 = pc[21]; p23 = pc[22];
1481       p24 = pc[23]; p25 = pc[24];
1482       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1483           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1484           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1485           || p16 != 0.0 || p17 != 0.0 || p18 != 0.0 || p19 != 0.0 || p20 != 0.0
1486           || p21 != 0.0 || p22 != 0.0 || p23 != 0.0 || p24 != 0.0 || p25 != 0.0) {
1487         pv = ba + 25*diag_offset[row];
1488         pj = bj + diag_offset[row] + 1;
1489         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1490         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1491         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1492         x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17]; x19 = pv[18];
1493         x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22]; x24 = pv[23];
1494         x25 = pv[24];
1495         pc[0] = m1 = p1*x1 + p6*x2  + p11*x3 + p16*x4 + p21*x5;
1496         pc[1] = m2 = p2*x1 + p7*x2  + p12*x3 + p17*x4 + p22*x5;
1497         pc[2] = m3 = p3*x1 + p8*x2  + p13*x3 + p18*x4 + p23*x5;
1498         pc[3] = m4 = p4*x1 + p9*x2  + p14*x3 + p19*x4 + p24*x5;
1499         pc[4] = m5 = p5*x1 + p10*x2 + p15*x3 + p20*x4 + p25*x5;
1500 
1501         pc[5]  = m6  = p1*x6 + p6*x7  + p11*x8 + p16*x9 + p21*x10;
1502         pc[6]  = m7  = p2*x6 + p7*x7  + p12*x8 + p17*x9 + p22*x10;
1503         pc[7]  = m8  = p3*x6 + p8*x7  + p13*x8 + p18*x9 + p23*x10;
1504         pc[8]  = m9  = p4*x6 + p9*x7  + p14*x8 + p19*x9 + p24*x10;
1505         pc[9]  = m10 = p5*x6 + p10*x7 + p15*x8 + p20*x9 + p25*x10;
1506 
1507         pc[10] = m11 = p1*x11 + p6*x12  + p11*x13 + p16*x14 + p21*x15;
1508         pc[11] = m12 = p2*x11 + p7*x12  + p12*x13 + p17*x14 + p22*x15;
1509         pc[12] = m13 = p3*x11 + p8*x12  + p13*x13 + p18*x14 + p23*x15;
1510         pc[13] = m14 = p4*x11 + p9*x12  + p14*x13 + p19*x14 + p24*x15;
1511         pc[14] = m15 = p5*x11 + p10*x12 + p15*x13 + p20*x14 + p25*x15;
1512 
1513         pc[15] = m16 = p1*x16 + p6*x17  + p11*x18 + p16*x19 + p21*x20;
1514         pc[16] = m17 = p2*x16 + p7*x17  + p12*x18 + p17*x19 + p22*x20;
1515         pc[17] = m18 = p3*x16 + p8*x17  + p13*x18 + p18*x19 + p23*x20;
1516         pc[18] = m19 = p4*x16 + p9*x17  + p14*x18 + p19*x19 + p24*x20;
1517         pc[19] = m20 = p5*x16 + p10*x17 + p15*x18 + p20*x19 + p25*x20;
1518 
1519         pc[20] = m21 = p1*x21 + p6*x22  + p11*x23 + p16*x24 + p21*x25;
1520         pc[21] = m22 = p2*x21 + p7*x22  + p12*x23 + p17*x24 + p22*x25;
1521         pc[22] = m23 = p3*x21 + p8*x22  + p13*x23 + p18*x24 + p23*x25;
1522         pc[23] = m24 = p4*x21 + p9*x22  + p14*x23 + p19*x24 + p24*x25;
1523         pc[24] = m25 = p5*x21 + p10*x22 + p15*x23 + p20*x24 + p25*x25;
1524 
1525         nz = bi[row+1] - diag_offset[row] - 1;
1526         pv += 25;
1527         for (j=0; j<nz; j++) {
1528           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1529           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1530           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1531           x14  = pv[13]; x15 = pv[14]; x16 = pv[15]; x17 = pv[16]; x18 = pv[17];
1532           x19 = pv[18];  x20 = pv[19]; x21 = pv[20]; x22 = pv[21]; x23 = pv[22];
1533           x24 = pv[23];  x25 = pv[24];
1534           x    = rtmp + 25*pj[j];
1535           x[0] -= m1*x1 + m6*x2   + m11*x3  + m16*x4 + m21*x5;
1536           x[1] -= m2*x1 + m7*x2   + m12*x3  + m17*x4 + m22*x5;
1537           x[2] -= m3*x1 + m8*x2   + m13*x3  + m18*x4 + m23*x5;
1538           x[3] -= m4*x1 + m9*x2   + m14*x3  + m19*x4 + m24*x5;
1539           x[4] -= m5*x1 + m10*x2  + m15*x3  + m20*x4 + m25*x5;
1540 
1541           x[5] -= m1*x6 + m6*x7   + m11*x8  + m16*x9 + m21*x10;
1542           x[6] -= m2*x6 + m7*x7   + m12*x8  + m17*x9 + m22*x10;
1543           x[7] -= m3*x6 + m8*x7   + m13*x8  + m18*x9 + m23*x10;
1544           x[8] -= m4*x6 + m9*x7   + m14*x8  + m19*x9 + m24*x10;
1545           x[9] -= m5*x6 + m10*x7  + m15*x8  + m20*x9 + m25*x10;
1546 
1547           x[10] -= m1*x11 + m6*x12  + m11*x13 + m16*x14 + m21*x15;
1548           x[11] -= m2*x11 + m7*x12  + m12*x13 + m17*x14 + m22*x15;
1549           x[12] -= m3*x11 + m8*x12  + m13*x13 + m18*x14 + m23*x15;
1550           x[13] -= m4*x11 + m9*x12  + m14*x13 + m19*x14 + m24*x15;
1551           x[14] -= m5*x11 + m10*x12 + m15*x13 + m20*x14 + m25*x15;
1552 
1553           x[15] -= m1*x16 + m6*x17  + m11*x18 + m16*x19 + m21*x20;
1554           x[16] -= m2*x16 + m7*x17  + m12*x18 + m17*x19 + m22*x20;
1555           x[17] -= m3*x16 + m8*x17  + m13*x18 + m18*x19 + m23*x20;
1556           x[18] -= m4*x16 + m9*x17  + m14*x18 + m19*x19 + m24*x20;
1557           x[19] -= m5*x16 + m10*x17 + m15*x18 + m20*x19 + m25*x20;
1558 
1559           x[20] -= m1*x21 + m6*x22  + m11*x23 + m16*x24 + m21*x25;
1560           x[21] -= m2*x21 + m7*x22  + m12*x23 + m17*x24 + m22*x25;
1561           x[22] -= m3*x21 + m8*x22  + m13*x23 + m18*x24 + m23*x25;
1562           x[23] -= m4*x21 + m9*x22  + m14*x23 + m19*x24 + m24*x25;
1563           x[24] -= m5*x21 + m10*x22 + m15*x23 + m20*x24 + m25*x25;
1564           pv   += 25;
1565         }
1566         PLogFlops(250*nz+225);
1567       }
1568       row = *ajtmp++;
1569     }
1570     /* finished row so stick it into b->a */
1571     pv = ba + 25*bi[i];
1572     pj = bj + bi[i];
1573     nz = bi[i+1] - bi[i];
1574     for (j=0; j<nz; j++) {
1575       x      = rtmp+25*pj[j];
1576       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1577       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1578       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1579       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15]; pv[16] = x[16]; pv[17] = x[17];
1580       pv[18] = x[18]; pv[19] = x[19]; pv[20] = x[20]; pv[21] = x[21]; pv[22] = x[22];
1581       pv[23] = x[23]; pv[24] = x[24];
1582       pv   += 25;
1583     }
1584     /* invert diagonal block */
1585     w = ba + 25*diag_offset[i];
1586     ierr = Kernel_A_gets_inverse_A_5(w);CHKERRQ(ierr);
1587   }
1588 
1589   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1590   C->factor    = FACTOR_LU;
1591   C->assembled = PETSC_TRUE;
1592   PLogFlops(1.3333*125*b->mbs); /* from inverting diagonal blocks */
1593   PetscFunctionReturn(0);
1594 }
1595 
1596 /* ------------------------------------------------------------*/
1597 /*
1598       Version for when blocks are 4 by 4
1599 */
1600 #undef __FUNC__
1601 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4"
1602 int MatLUFactorNumeric_SeqBAIJ_4(Mat A,Mat *B)
1603 {
1604   Mat         C = *B;
1605   Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
1606   IS          isrow = b->row,isicol = b->icol;
1607   int         *r,*ic,ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
1608   int         *ajtmpold,*ajtmp,nz,row;
1609   int         *diag_offset = b->diag,idx,*ai=a->i,*aj=a->j,*pj;
1610   MatScalar   *pv,*v,*rtmp,*pc,*w,*x;
1611   MatScalar   p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1612   MatScalar   p5,p6,p7,p8,p9,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16;
1613   MatScalar   p10,p11,p12,p13,p14,p15,p16,m10,m11,m12;
1614   MatScalar   m13,m14,m15,m16;
1615   MatScalar   *ba = b->a,*aa = a->a;
1616 
1617   PetscFunctionBegin;
1618   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1619   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1620   rtmp  = (MatScalar*)PetscMalloc(16*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1621 
1622   for (i=0; i<n; i++) {
1623     nz    = bi[i+1] - bi[i];
1624     ajtmp = bj + bi[i];
1625     for  (j=0; j<nz; j++) {
1626       x = rtmp+16*ajtmp[j];
1627       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = x[9] = 0.0;
1628       x[10] = x[11] = x[12] = x[13] = x[14] = x[15] = 0.0;
1629     }
1630     /* load in initial (unfactored row) */
1631     idx      = r[i];
1632     nz       = ai[idx+1] - ai[idx];
1633     ajtmpold = aj + ai[idx];
1634     v        = aa + 16*ai[idx];
1635     for (j=0; j<nz; j++) {
1636       x    = rtmp+16*ic[ajtmpold[j]];
1637       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
1638       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
1639       x[9]  = v[9];  x[10] = v[10]; x[11] = v[11]; x[12] = v[12]; x[13] = v[13];
1640       x[14] = v[14]; x[15] = v[15];
1641       v    += 16;
1642     }
1643     row = *ajtmp++;
1644     while (row < i) {
1645       pc  = rtmp + 16*row;
1646       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
1647       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
1648       p10 = pc[9];  p11 = pc[10]; p12 = pc[11]; p13 = pc[12]; p14 = pc[13];
1649       p15 = pc[14]; p16 = pc[15];
1650       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1651           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0 || p10 != 0.0 ||
1652           p11 != 0.0 || p12 != 0.0 || p13 != 0.0 || p14 != 0.0 || p15 != 0.0
1653           || p16 != 0.0) {
1654         pv = ba + 16*diag_offset[row];
1655         pj = bj + diag_offset[row] + 1;
1656         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
1657         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
1658         x10 = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12]; x14 = pv[13];
1659         x15 = pv[14]; x16 = pv[15];
1660         pc[0] = m1 = p1*x1 + p5*x2  + p9*x3  + p13*x4;
1661         pc[1] = m2 = p2*x1 + p6*x2  + p10*x3 + p14*x4;
1662         pc[2] = m3 = p3*x1 + p7*x2  + p11*x3 + p15*x4;
1663         pc[3] = m4 = p4*x1 + p8*x2  + p12*x3 + p16*x4;
1664 
1665         pc[4] = m5 = p1*x5 + p5*x6  + p9*x7  + p13*x8;
1666         pc[5] = m6 = p2*x5 + p6*x6  + p10*x7 + p14*x8;
1667         pc[6] = m7 = p3*x5 + p7*x6  + p11*x7 + p15*x8;
1668         pc[7] = m8 = p4*x5 + p8*x6  + p12*x7 + p16*x8;
1669 
1670         pc[8]  = m9  = p1*x9 + p5*x10  + p9*x11  + p13*x12;
1671         pc[9]  = m10 = p2*x9 + p6*x10  + p10*x11 + p14*x12;
1672         pc[10] = m11 = p3*x9 + p7*x10  + p11*x11 + p15*x12;
1673         pc[11] = m12 = p4*x9 + p8*x10  + p12*x11 + p16*x12;
1674 
1675         pc[12] = m13 = p1*x13 + p5*x14  + p9*x15  + p13*x16;
1676         pc[13] = m14 = p2*x13 + p6*x14  + p10*x15 + p14*x16;
1677         pc[14] = m15 = p3*x13 + p7*x14  + p11*x15 + p15*x16;
1678         pc[15] = m16 = p4*x13 + p8*x14  + p12*x15 + p16*x16;
1679 
1680         nz = bi[row+1] - diag_offset[row] - 1;
1681         pv += 16;
1682         for (j=0; j<nz; j++) {
1683           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
1684           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
1685           x10  = pv[9];  x11 = pv[10]; x12 = pv[11]; x13 = pv[12];
1686           x14  = pv[13]; x15 = pv[14]; x16 = pv[15];
1687           x    = rtmp + 16*pj[j];
1688           x[0] -= m1*x1 + m5*x2  + m9*x3  + m13*x4;
1689           x[1] -= m2*x1 + m6*x2  + m10*x3 + m14*x4;
1690           x[2] -= m3*x1 + m7*x2  + m11*x3 + m15*x4;
1691           x[3] -= m4*x1 + m8*x2  + m12*x3 + m16*x4;
1692 
1693           x[4] -= m1*x5 + m5*x6  + m9*x7  + m13*x8;
1694           x[5] -= m2*x5 + m6*x6  + m10*x7 + m14*x8;
1695           x[6] -= m3*x5 + m7*x6  + m11*x7 + m15*x8;
1696           x[7] -= m4*x5 + m8*x6  + m12*x7 + m16*x8;
1697 
1698           x[8]  -= m1*x9 + m5*x10 + m9*x11  + m13*x12;
1699           x[9]  -= m2*x9 + m6*x10 + m10*x11 + m14*x12;
1700           x[10] -= m3*x9 + m7*x10 + m11*x11 + m15*x12;
1701           x[11] -= m4*x9 + m8*x10 + m12*x11 + m16*x12;
1702 
1703           x[12] -= m1*x13 + m5*x14  + m9*x15  + m13*x16;
1704           x[13] -= m2*x13 + m6*x14  + m10*x15 + m14*x16;
1705           x[14] -= m3*x13 + m7*x14  + m11*x15 + m15*x16;
1706           x[15] -= m4*x13 + m8*x14  + m12*x15 + m16*x16;
1707 
1708           pv   += 16;
1709         }
1710         PLogFlops(128*nz+112);
1711       }
1712       row = *ajtmp++;
1713     }
1714     /* finished row so stick it into b->a */
1715     pv = ba + 16*bi[i];
1716     pj = bj + bi[i];
1717     nz = bi[i+1] - bi[i];
1718     for (j=0; j<nz; j++) {
1719       x      = rtmp+16*pj[j];
1720       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
1721       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
1722       pv[9]  = x[9];  pv[10] = x[10]; pv[11] = x[11]; pv[12] = x[12];
1723       pv[13] = x[13]; pv[14] = x[14]; pv[15] = x[15];
1724       pv   += 16;
1725     }
1726     /* invert diagonal block */
1727     w = ba + 16*diag_offset[i];
1728     ierr = Kernel_A_gets_inverse_A_4(w);CHKERRQ(ierr);
1729   }
1730 
1731   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1732   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1733   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1734   C->factor = FACTOR_LU;
1735   C->assembled = PETSC_TRUE;
1736   PLogFlops(1.3333*64*b->mbs); /* from inverting diagonal blocks */
1737   PetscFunctionReturn(0);
1738 }
1739 /*
1740       Version for when blocks are 4 by 4 Using natural ordering
1741 */
1742 #undef __FUNC__
1743 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering"
1744 int MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering(Mat A,Mat *B)
1745 {
1746   Mat         C = *B;
1747   Mat_SeqBAIJ *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
1748   int         ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
1749   int         *ajtmpold,*ajtmp,nz,row;
1750   int         *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
1751   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,*pj;
1891   MatScalar   *pv,*v,*rtmp,*pc,*w,*x;
1892   MatScalar   p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
1893   MatScalar   p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
1894   MatScalar   *ba = b->a,*aa = a->a;
1895 
1896   PetscFunctionBegin;
1897   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
1898   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
1899   rtmp  = (MatScalar*)PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
1900 
1901   for (i=0; i<n; i++) {
1902     nz    = bi[i+1] - bi[i];
1903     ajtmp = bj + bi[i];
1904     for  (j=0; j<nz; j++) {
1905       x = rtmp + 9*ajtmp[j];
1906       x[0] = x[1] = x[2] = x[3] = x[4] = x[5] = x[6] = x[7] = x[8] = 0.0;
1907     }
1908     /* load in initial (unfactored row) */
1909     idx      = r[i];
1910     nz       = ai[idx+1] - ai[idx];
1911     ajtmpold = aj + ai[idx];
1912     v        = aa + 9*ai[idx];
1913     for (j=0; j<nz; j++) {
1914       x    = rtmp + 9*ic[ajtmpold[j]];
1915       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
1916       x[4] = v[4]; x[5] = v[5]; x[6] = v[6]; x[7] = v[7]; x[8] = v[8];
1917       v    += 9;
1918     }
1919     row = *ajtmp++;
1920     while (row < i) {
1921       pc = rtmp + 9*row;
1922       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
1923       p5 = pc[4]; p6 = pc[5]; p7 = pc[6]; p8 = pc[7]; p9 = pc[8];
1924       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
1925           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
1926         pv = ba + 9*diag_offset[row];
1927         pj = bj + diag_offset[row] + 1;
1928         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1929         x5 = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1930         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
1931         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
1932         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
1933 
1934         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
1935         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
1936         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
1937 
1938         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
1939         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
1940         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
1941         nz = bi[row+1] - diag_offset[row] - 1;
1942         pv += 9;
1943         for (j=0; j<nz; j++) {
1944           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
1945           x5   = pv[4]; x6 = pv[5]; x7 = pv[6]; x8 = pv[7]; x9 = pv[8];
1946           x    = rtmp + 9*pj[j];
1947           x[0] -= m1*x1 + m4*x2 + m7*x3;
1948           x[1] -= m2*x1 + m5*x2 + m8*x3;
1949           x[2] -= m3*x1 + m6*x2 + m9*x3;
1950 
1951           x[3] -= m1*x4 + m4*x5 + m7*x6;
1952           x[4] -= m2*x4 + m5*x5 + m8*x6;
1953           x[5] -= m3*x4 + m6*x5 + m9*x6;
1954 
1955           x[6] -= m1*x7 + m4*x8 + m7*x9;
1956           x[7] -= m2*x7 + m5*x8 + m8*x9;
1957           x[8] -= m3*x7 + m6*x8 + m9*x9;
1958           pv   += 9;
1959         }
1960         PLogFlops(54*nz+36);
1961       }
1962       row = *ajtmp++;
1963     }
1964     /* finished row so stick it into b->a */
1965     pv = ba + 9*bi[i];
1966     pj = bj + bi[i];
1967     nz = bi[i+1] - bi[i];
1968     for (j=0; j<nz; j++) {
1969       x     = rtmp + 9*pj[j];
1970       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
1971       pv[4] = x[4]; pv[5] = x[5]; pv[6] = x[6]; pv[7] = x[7]; pv[8] = x[8];
1972       pv   += 9;
1973     }
1974     /* invert diagonal block */
1975     w = ba + 9*diag_offset[i];
1976     ierr = Kernel_A_gets_inverse_A_3(w);CHKERRQ(ierr);
1977   }
1978 
1979   ierr = PetscFree(rtmp);CHKERRQ(ierr);
1980   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
1981   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
1982   C->factor = FACTOR_LU;
1983   C->assembled = PETSC_TRUE;
1984   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
1985   PetscFunctionReturn(0);
1986 }
1987 /*
1988       Version for when blocks are 3 by 3 Using natural ordering
1989 */
1990 #undef __FUNC__
1991 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering"
1992 int MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering(Mat A,Mat *B)
1993 {
1994   Mat                C = *B;
1995   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
1996   int                ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
1997   int                *ajtmpold,*ajtmp,nz,row;
1998   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
1999   MatScalar          *pv,*v,*rtmp,*pc,*w,*x;
2000   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
2001   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
2002   MatScalar          *ba = b->a,*aa = a->a;
2003 
2004   PetscFunctionBegin;
2005   rtmp  = (MatScalar*)PetscMalloc(9*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2006 
2007   for (i=0; i<n; i++) {
2008     nz    = bi[i+1] - bi[i];
2009     ajtmp = bj + bi[i];
2010     for  (j=0; j<nz; j++) {
2011       x = rtmp+9*ajtmp[j];
2012       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = 0.0;
2013     }
2014     /* load in initial (unfactored row) */
2015     nz       = ai[i+1] - ai[i];
2016     ajtmpold = aj + ai[i];
2017     v        = aa + 9*ai[i];
2018     for (j=0; j<nz; j++) {
2019       x    = rtmp+9*ajtmpold[j];
2020       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2021       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
2022       v    += 9;
2023     }
2024     row = *ajtmp++;
2025     while (row < i) {
2026       pc  = rtmp + 9*row;
2027       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2028       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
2029       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
2030           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
2031         pv = ba + 9*diag_offset[row];
2032         pj = bj + diag_offset[row] + 1;
2033         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2034         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
2035         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
2036         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
2037         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;
2038 
2039         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
2040         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
2041         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;
2042 
2043         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
2044         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
2045         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;
2046 
2047         nz = bi[row+1] - diag_offset[row] - 1;
2048         pv += 9;
2049         for (j=0; j<nz; j++) {
2050           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2051           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
2052           x    = rtmp + 9*pj[j];
2053           x[0] -= m1*x1 + m4*x2 + m7*x3;
2054           x[1] -= m2*x1 + m5*x2 + m8*x3;
2055           x[2] -= m3*x1 + m6*x2 + m9*x3;
2056 
2057           x[3] -= m1*x4 + m4*x5 + m7*x6;
2058           x[4] -= m2*x4 + m5*x5 + m8*x6;
2059           x[5] -= m3*x4 + m6*x5 + m9*x6;
2060 
2061           x[6] -= m1*x7 + m4*x8 + m7*x9;
2062           x[7] -= m2*x7 + m5*x8 + m8*x9;
2063           x[8] -= m3*x7 + m6*x8 + m9*x9;
2064           pv   += 9;
2065         }
2066         PLogFlops(54*nz+36);
2067       }
2068       row = *ajtmp++;
2069     }
2070     /* finished row so stick it into b->a */
2071     pv = ba + 9*bi[i];
2072     pj = bj + bi[i];
2073     nz = bi[i+1] - bi[i];
2074     for (j=0; j<nz; j++) {
2075       x      = rtmp+9*pj[j];
2076       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2077       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
2078       pv   += 9;
2079     }
2080     /* invert diagonal block */
2081     w = ba + 9*diag_offset[i];
2082     ierr = Kernel_A_gets_inverse_A_3(w);CHKERRQ(ierr);
2083   }
2084 
2085   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2086   C->factor    = FACTOR_LU;
2087   C->assembled = PETSC_TRUE;
2088   PLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
2089   PetscFunctionReturn(0);
2090 }
2091 
2092 /* ------------------------------------------------------------*/
2093 /*
2094       Version for when blocks are 2 by 2
2095 */
2096 #undef __FUNC__
2097 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2"
2098 int MatLUFactorNumeric_SeqBAIJ_2(Mat A,Mat *B)
2099 {
2100   Mat                C = *B;
2101   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
2102   IS                 isrow = b->row,isicol = b->icol;
2103   int                *r,*ic,ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
2104   int                *ajtmpold,*ajtmp,nz,row;
2105   int                *diag_offset=b->diag,idx,*ai=a->i,*aj=a->j,*pj;
2106   MatScalar          *pv,*v,*rtmp,m1,m2,m3,m4,*pc,*w,*x,x1,x2,x3,x4;
2107   MatScalar          p1,p2,p3,p4;
2108   MatScalar          *ba = b->a,*aa = a->a;
2109 
2110   PetscFunctionBegin;
2111   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
2112   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
2113   rtmp  = (MatScalar*)PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2114 
2115   for (i=0; i<n; i++) {
2116     nz    = bi[i+1] - bi[i];
2117     ajtmp = bj + bi[i];
2118     for  (j=0; j<nz; j++) {
2119       x = rtmp+4*ajtmp[j]; x[0] = x[1] = x[2] = x[3] = 0.0;
2120     }
2121     /* load in initial (unfactored row) */
2122     idx      = r[i];
2123     nz       = ai[idx+1] - ai[idx];
2124     ajtmpold = aj + ai[idx];
2125     v        = aa + 4*ai[idx];
2126     for (j=0; j<nz; j++) {
2127       x    = rtmp+4*ic[ajtmpold[j]];
2128       x[0] = v[0]; x[1] = v[1]; x[2] = v[2]; x[3] = v[3];
2129       v    += 4;
2130     }
2131     row = *ajtmp++;
2132     while (row < i) {
2133       pc = rtmp + 4*row;
2134       p1 = pc[0]; p2 = pc[1]; p3 = pc[2]; p4 = pc[3];
2135       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2136         pv = ba + 4*diag_offset[row];
2137         pj = bj + diag_offset[row] + 1;
2138         x1 = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2139         pc[0] = m1 = p1*x1 + p3*x2;
2140         pc[1] = m2 = p2*x1 + p4*x2;
2141         pc[2] = m3 = p1*x3 + p3*x4;
2142         pc[3] = m4 = p2*x3 + p4*x4;
2143         nz = bi[row+1] - diag_offset[row] - 1;
2144         pv += 4;
2145         for (j=0; j<nz; j++) {
2146           x1   = pv[0]; x2 = pv[1]; x3 = pv[2]; x4 = pv[3];
2147           x    = rtmp + 4*pj[j];
2148           x[0] -= m1*x1 + m3*x2;
2149           x[1] -= m2*x1 + m4*x2;
2150           x[2] -= m1*x3 + m3*x4;
2151           x[3] -= m2*x3 + m4*x4;
2152           pv   += 4;
2153         }
2154         PLogFlops(16*nz+12);
2155       }
2156       row = *ajtmp++;
2157     }
2158     /* finished row so stick it into b->a */
2159     pv = ba + 4*bi[i];
2160     pj = bj + bi[i];
2161     nz = bi[i+1] - bi[i];
2162     for (j=0; j<nz; j++) {
2163       x     = rtmp+4*pj[j];
2164       pv[0] = x[0]; pv[1] = x[1]; pv[2] = x[2]; pv[3] = x[3];
2165       pv   += 4;
2166     }
2167     /* invert diagonal block */
2168     w = ba + 4*diag_offset[i];
2169     ierr = Kernel_A_gets_inverse_A_2(w);CHKERRQ(ierr);
2170     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2171   }
2172 
2173   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2174   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
2175   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
2176   C->factor = FACTOR_LU;
2177   C->assembled = PETSC_TRUE;
2178   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2179   PetscFunctionReturn(0);
2180 }
2181 /*
2182       Version for when blocks are 2 by 2 Using natural ordering
2183 */
2184 #undef __FUNC__
2185 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering"
2186 int MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering(Mat A,Mat *B)
2187 {
2188   Mat                C = *B;
2189   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
2190   int                ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
2191   int                *ajtmpold,*ajtmp,nz,row;
2192   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
2193   MatScalar          *pv,*v,*rtmp,*pc,*w,*x;
2194   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,x1,x2,x3,x4;
2195   MatScalar          *ba = b->a,*aa = a->a;
2196 
2197   PetscFunctionBegin;
2198   rtmp  = (MatScalar*)PetscMalloc(4*(n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2199 
2200   for (i=0; i<n; i++) {
2201     nz    = bi[i+1] - bi[i];
2202     ajtmp = bj + bi[i];
2203     for  (j=0; j<nz; j++) {
2204       x = rtmp+4*ajtmp[j];
2205       x[0]  = x[1]  = x[2]  = x[3]  = 0.0;
2206     }
2207     /* load in initial (unfactored row) */
2208     nz       = ai[i+1] - ai[i];
2209     ajtmpold = aj + ai[i];
2210     v        = aa + 4*ai[i];
2211     for (j=0; j<nz; j++) {
2212       x    = rtmp+4*ajtmpold[j];
2213       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
2214       v    += 4;
2215     }
2216     row = *ajtmp++;
2217     while (row < i) {
2218       pc  = rtmp + 4*row;
2219       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
2220       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0) {
2221         pv = ba + 4*diag_offset[row];
2222         pj = bj + diag_offset[row] + 1;
2223         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
2224         pc[0] = m1 = p1*x1 + p3*x2;
2225         pc[1] = m2 = p2*x1 + p4*x2;
2226         pc[2] = m3 = p1*x3 + p3*x4;
2227         pc[3] = m4 = p2*x3 + p4*x4;
2228         nz = bi[row+1] - diag_offset[row] - 1;
2229         pv += 4;
2230         for (j=0; j<nz; j++) {
2231           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
2232           x    = rtmp + 4*pj[j];
2233           x[0] -= m1*x1 + m3*x2;
2234           x[1] -= m2*x1 + m4*x2;
2235           x[2] -= m1*x3 + m3*x4;
2236           x[3] -= m2*x3 + m4*x4;
2237           pv   += 4;
2238         }
2239         PLogFlops(16*nz+12);
2240       }
2241       row = *ajtmp++;
2242     }
2243     /* finished row so stick it into b->a */
2244     pv = ba + 4*bi[i];
2245     pj = bj + bi[i];
2246     nz = bi[i+1] - bi[i];
2247     for (j=0; j<nz; j++) {
2248       x      = rtmp+4*pj[j];
2249       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
2250       pv   += 4;
2251     }
2252     /* invert diagonal block */
2253     w = ba + 4*diag_offset[i];
2254     ierr = Kernel_A_gets_inverse_A_2(w);CHKERRQ(ierr);
2255     /*Kernel_A_gets_inverse_A(bs,w,v_pivots,v_work);*/
2256   }
2257 
2258   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2259   C->factor    = FACTOR_LU;
2260   C->assembled = PETSC_TRUE;
2261   PLogFlops(1.3333*8*b->mbs); /* from inverting diagonal blocks */
2262   PetscFunctionReturn(0);
2263 }
2264 
2265 /* ----------------------------------------------------------- */
2266 /*
2267      Version for when blocks are 1 by 1.
2268 */
2269 #undef __FUNC__
2270 #define __FUNC__ "MatLUFactorNumeric_SeqBAIJ_1"
2271 int MatLUFactorNumeric_SeqBAIJ_1(Mat A,Mat *B)
2272 {
2273   Mat                C = *B;
2274   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
2275   IS                 isrow = b->row,isicol = b->icol;
2276   int                *r,*ic,ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
2277   int                *ajtmpold,*ajtmp,nz,row,*ai = a->i,*aj = a->j;
2278   int                *diag_offset = b->diag,diag,*pj;
2279   MatScalar          *pv,*v,*rtmp,multiplier,*pc;
2280   MatScalar          *ba = b->a,*aa = a->a;
2281 
2282   PetscFunctionBegin;
2283   ierr  = ISGetIndices(isrow,&r);CHKERRQ(ierr);
2284   ierr  = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
2285   rtmp  = (MatScalar*)PetscMalloc((n+1)*sizeof(MatScalar));CHKPTRQ(rtmp);
2286 
2287   for (i=0; i<n; i++) {
2288     nz    = bi[i+1] - bi[i];
2289     ajtmp = bj + bi[i];
2290     for  (j=0; j<nz; j++) rtmp[ajtmp[j]] = 0.0;
2291 
2292     /* load in initial (unfactored row) */
2293     nz       = ai[r[i]+1] - ai[r[i]];
2294     ajtmpold = aj + ai[r[i]];
2295     v        = aa + ai[r[i]];
2296     for (j=0; j<nz; j++) rtmp[ic[ajtmpold[j]]] =  v[j];
2297 
2298     row = *ajtmp++;
2299     while (row < i) {
2300       pc = rtmp + row;
2301       if (*pc != 0.0) {
2302         pv         = ba + diag_offset[row];
2303         pj         = bj + diag_offset[row] + 1;
2304         multiplier = *pc * *pv++;
2305         *pc        = multiplier;
2306         nz         = bi[row+1] - diag_offset[row] - 1;
2307         for (j=0; j<nz; j++) rtmp[pj[j]] -= multiplier * pv[j];
2308         PLogFlops(1+2*nz);
2309       }
2310       row = *ajtmp++;
2311     }
2312     /* finished row so stick it into b->a */
2313     pv = ba + bi[i];
2314     pj = bj + bi[i];
2315     nz = bi[i+1] - bi[i];
2316     for (j=0; j<nz; j++) {pv[j] = rtmp[pj[j]];}
2317     diag = diag_offset[i] - bi[i];
2318     /* check pivot entry for current row */
2319     if (pv[diag] == 0.0) {
2320       SETERRQ(PETSC_ERR_MAT_LU_ZRPVT,0,"Zero pivot");
2321     }
2322     pv[diag] = 1.0/pv[diag];
2323   }
2324 
2325   ierr = PetscFree(rtmp);CHKERRQ(ierr);
2326   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
2327   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
2328   C->factor    = FACTOR_LU;
2329   C->assembled = PETSC_TRUE;
2330   PLogFlops(b->n);
2331   PetscFunctionReturn(0);
2332 }
2333 
2334 /* ----------------------------------------------------------- */
2335 #undef __FUNC__
2336 #define __FUNC__ "MatLUFactor_SeqBAIJ"
2337 int MatLUFactor_SeqBAIJ(Mat A,IS row,IS col,PetscReal f)
2338 {
2339   Mat_SeqBAIJ    *mat = (Mat_SeqBAIJ*)A->data;
2340   int            ierr,refct;
2341   Mat            C;
2342   PetscOps *Abops;
2343   MatOps   Aops;
2344 
2345   PetscFunctionBegin;
2346   ierr = MatLUFactorSymbolic(A,row,col,f,&C);CHKERRQ(ierr);
2347   ierr = MatLUFactorNumeric(A,&C);CHKERRQ(ierr);
2348 
2349   /* free all the data structures from mat */
2350   ierr = PetscFree(mat->a);CHKERRQ(ierr);
2351   if (!mat->singlemalloc) {
2352     ierr = PetscFree(mat->i);CHKERRQ(ierr);
2353     ierr = PetscFree(mat->j);CHKERRQ(ierr);
2354   }
2355   if (mat->diag) {ierr = PetscFree(mat->diag);CHKERRQ(ierr);}
2356   if (mat->ilen) {ierr = PetscFree(mat->ilen);CHKERRQ(ierr);}
2357   if (mat->imax) {ierr = PetscFree(mat->imax);CHKERRQ(ierr);}
2358   if (mat->solve_work) {ierr = PetscFree(mat->solve_work);CHKERRQ(ierr);}
2359   if (mat->mult_work) {ierr = PetscFree(mat->mult_work);CHKERRQ(ierr);}
2360   if (mat->icol) {ierr = ISDestroy(mat->icol);CHKERRQ(ierr);}
2361   ierr = PetscFree(mat);CHKERRQ(ierr);
2362 
2363   ierr = MapDestroy(A->rmap);CHKERRQ(ierr);
2364   ierr = MapDestroy(A->cmap);CHKERRQ(ierr);
2365 
2366   /*
2367        This is horrible,horrible code. We need to keep the
2368     A pointers for the bops and ops but copy everything
2369     else from C.
2370   */
2371   Abops = A->bops;
2372   Aops  = A->ops;
2373   refct = A->refct;
2374   ierr  = PetscMemcpy(A,C,sizeof(struct _p_Mat));CHKERRQ(ierr);
2375   mat   = (Mat_SeqBAIJ*)A->data;
2376   PLogObjectParent(A,mat->icol);
2377 
2378   A->bops  = Abops;
2379   A->ops   = Aops;
2380   A->qlist = 0;
2381   A->refct = refct;
2382   /* copy over the type_name and name */
2383   ierr     = PetscStrallocpy(C->type_name,&A->type_name);CHKERRQ(ierr);
2384   ierr     = PetscStrallocpy(C->name,&A->name);CHKERRQ(ierr);
2385 
2386   PetscHeaderDestroy(C);
2387   PetscFunctionReturn(0);
2388 }
2389 
2390 
2391 
2392