Actual source code: baijfact14.c

  1: /*$Id: baijfact14.c,v 1.4 2001/03/23 23:22:07 balay Exp $*/
  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:       Version for when blocks are 3 by 3 Using natural ordering
 10: */
 11: int MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering(Mat A,Mat *B)
 12: {
 13:   Mat                C = *B;
 14:   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b = (Mat_SeqBAIJ *)C->data;
 15:   int                ierr,i,j,n = a->mbs,*bi = b->i,*bj = b->j;
 16:   int                *ajtmpold,*ajtmp,nz,row;
 17:   int                *diag_offset = b->diag,*ai=a->i,*aj=a->j,*pj;
 18:   MatScalar          *pv,*v,*rtmp,*pc,*w,*x;
 19:   MatScalar          p1,p2,p3,p4,m1,m2,m3,m4,m5,m6,m7,m8,m9,x1,x2,x3,x4;
 20:   MatScalar          p5,p6,p7,p8,p9,x5,x6,x7,x8,x9;
 21:   MatScalar          *ba = b->a,*aa = a->a;

 24:   PetscMalloc(9*(n+1)*sizeof(MatScalar),&rtmp);

 26:   for (i=0; i<n; i++) {
 27:     nz    = bi[i+1] - bi[i];
 28:     ajtmp = bj + bi[i];
 29:     for  (j=0; j<nz; j++) {
 30:       x = rtmp+9*ajtmp[j];
 31:       x[0]  = x[1]  = x[2]  = x[3]  = x[4]  = x[5]  = x[6] = x[7] = x[8] = 0.0;
 32:     }
 33:     /* load in initial (unfactored row) */
 34:     nz       = ai[i+1] - ai[i];
 35:     ajtmpold = aj + ai[i];
 36:     v        = aa + 9*ai[i];
 37:     for (j=0; j<nz; j++) {
 38:       x    = rtmp+9*ajtmpold[j];
 39:       x[0]  = v[0];  x[1]  = v[1];  x[2]  = v[2];  x[3]  = v[3];
 40:       x[4]  = v[4];  x[5]  = v[5];  x[6]  = v[6];  x[7]  = v[7];  x[8]  = v[8];
 41:       v    += 9;
 42:     }
 43:     row = *ajtmp++;
 44:     while (row < i) {
 45:       pc  = rtmp + 9*row;
 46:       p1  = pc[0];  p2  = pc[1];  p3  = pc[2];  p4  = pc[3];
 47:       p5  = pc[4];  p6  = pc[5];  p7  = pc[6];  p8  = pc[7];  p9  = pc[8];
 48:       if (p1 != 0.0 || p2 != 0.0 || p3 != 0.0 || p4 != 0.0 || p5 != 0.0 ||
 49:           p6 != 0.0 || p7 != 0.0 || p8 != 0.0 || p9 != 0.0) {
 50:         pv = ba + 9*diag_offset[row];
 51:         pj = bj + diag_offset[row] + 1;
 52:         x1  = pv[0];  x2  = pv[1];  x3  = pv[2];  x4  = pv[3];
 53:         x5  = pv[4];  x6  = pv[5];  x7  = pv[6];  x8  = pv[7];  x9  = pv[8];
 54:         pc[0] = m1 = p1*x1 + p4*x2 + p7*x3;
 55:         pc[1] = m2 = p2*x1 + p5*x2 + p8*x3;
 56:         pc[2] = m3 = p3*x1 + p6*x2 + p9*x3;

 58:         pc[3] = m4 = p1*x4 + p4*x5 + p7*x6;
 59:         pc[4] = m5 = p2*x4 + p5*x5 + p8*x6;
 60:         pc[5] = m6 = p3*x4 + p6*x5 + p9*x6;

 62:         pc[6] = m7 = p1*x7 + p4*x8 + p7*x9;
 63:         pc[7] = m8 = p2*x7 + p5*x8 + p8*x9;
 64:         pc[8] = m9 = p3*x7 + p6*x8 + p9*x9;

 66:         nz = bi[row+1] - diag_offset[row] - 1;
 67:         pv += 9;
 68:         for (j=0; j<nz; j++) {
 69:           x1   = pv[0];  x2  = pv[1];   x3 = pv[2];  x4  = pv[3];
 70:           x5   = pv[4];  x6  = pv[5];   x7 = pv[6];  x8  = pv[7]; x9 = pv[8];
 71:           x    = rtmp + 9*pj[j];
 72:           x[0] -= m1*x1 + m4*x2 + m7*x3;
 73:           x[1] -= m2*x1 + m5*x2 + m8*x3;
 74:           x[2] -= m3*x1 + m6*x2 + m9*x3;
 75: 
 76:           x[3] -= m1*x4 + m4*x5 + m7*x6;
 77:           x[4] -= m2*x4 + m5*x5 + m8*x6;
 78:           x[5] -= m3*x4 + m6*x5 + m9*x6;

 80:           x[6] -= m1*x7 + m4*x8 + m7*x9;
 81:           x[7] -= m2*x7 + m5*x8 + m8*x9;
 82:           x[8] -= m3*x7 + m6*x8 + m9*x9;
 83:           pv   += 9;
 84:         }
 85:         PetscLogFlops(54*nz+36);
 86:       }
 87:       row = *ajtmp++;
 88:     }
 89:     /* finished row so stick it into b->a */
 90:     pv = ba + 9*bi[i];
 91:     pj = bj + bi[i];
 92:     nz = bi[i+1] - bi[i];
 93:     for (j=0; j<nz; j++) {
 94:       x      = rtmp+9*pj[j];
 95:       pv[0]  = x[0];  pv[1]  = x[1];  pv[2]  = x[2];  pv[3]  = x[3];
 96:       pv[4]  = x[4];  pv[5]  = x[5];  pv[6]  = x[6];  pv[7]  = x[7]; pv[8] = x[8];
 97:       pv   += 9;
 98:     }
 99:     /* invert diagonal block */
100:     w = ba + 9*diag_offset[i];
101:     Kernel_A_gets_inverse_A_3(w);
102:   }

104:   PetscFree(rtmp);
105:   C->factor    = FACTOR_LU;
106:   C->assembled = PETSC_TRUE;
107:   PetscLogFlops(1.3333*27*b->mbs); /* from inverting diagonal blocks */
108:   return(0);
109: }