2: static char help[] = "Tests Cholesky factorization for a SBAIJ matrix, (bs=2).\n";
  3: /*
  4:   This code is modified from the code contributed by JUNWANG@uwm.edu on Apr 13, 2007
  5: */

  7: #include <petscmat.h>

 11: int main(int argc,char **args)
 12: {
 14:   Mat            mat,fact,B;
 15:   PetscInt       ind1[2],ind2[2];
 16:   PetscScalar    temp[4];
 17:   PetscInt       nnz[3];
 18:   IS             perm,colp;
 19:   MatFactorInfo  info;
 20:   PetscMPIInt    size;

 22:   PetscInitialize(&argc,&args,0,help);
 23:   MPI_Comm_size(PETSC_COMM_WORLD,&size);
 24:   if (size != 1) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP,"This is a uniprocessor example only!");

 26:   nnz[0]=2;nnz[1]=1;nnz[2]=1;
 27:   MatCreateSeqSBAIJ(PETSC_COMM_SELF,2,6,6,0,nnz,&mat);
 28: 
 29:   ind1[0]=0;ind1[1]=1;
 30:   temp[0]=3;temp[1]=2;temp[2]=0;temp[3]=3;
 31:   MatSetValues(mat,2,ind1,2,ind1,temp,INSERT_VALUES);
 32:   ind2[0]=4;ind2[1]=5;
 33:   temp[0]=1;temp[1]=1;temp[2]=2;temp[3]=1;
 34:   MatSetValues(mat,2,ind1,2,ind2,temp,INSERT_VALUES);
 35:   ind1[0]=2;ind1[1]=3;
 36:   temp[0]=4;temp[1]=1;temp[2]=1;temp[3]=5;
 37:   MatSetValues(mat,2,ind1,2,ind1,temp,INSERT_VALUES);
 38:   ind1[0]=4;ind1[1]=5;
 39:   temp[0]=5;temp[1]=1;temp[2]=1;temp[3]=6;
 40:   MatSetValues(mat,2,ind1,2,ind1,temp,INSERT_VALUES);

 42:   MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);
 43:   MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);

 45:   MatDuplicate(mat,MAT_SHARE_NONZERO_PATTERN,&B);
 46:   ind1[0]=0;ind1[1]=1;
 47:   temp[0]=3;temp[1]=2;temp[2]=0;temp[3]=3;
 48:   MatSetValues(mat,2,ind1,2,ind1,temp,INSERT_VALUES);
 49:   ind2[0]=4;ind2[1]=5;
 50:   temp[0]=1;temp[1]=1;temp[2]=2;temp[3]=1;
 51:   MatSetValues(mat,2,ind1,2,ind2,temp,INSERT_VALUES);
 52:   ind1[0]=2;ind1[1]=3;
 53:   temp[0]=4;temp[1]=1;temp[2]=1;temp[3]=5;
 54:   MatSetValues(mat,2,ind1,2,ind1,temp,INSERT_VALUES);
 55:   ind1[0]=4;ind1[1]=5;
 56:   temp[0]=5;temp[1]=1;temp[2]=1;temp[3]=6;
 57:   MatSetValues(mat,2,ind1,2,ind1,temp,INSERT_VALUES);

 59:   MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);
 60:   MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);

 62:   PetscPrintf(PETSC_COMM_WORLD,"mat: \n");
 63:   MatView(mat,PETSC_VIEWER_STDOUT_SELF);

 65:   /* begin cholesky factorization */
 66:   MatGetOrdering(mat,MATORDERINGNATURAL,&perm,&colp);
 67:   ISDestroy(&colp);

 69:   info.fill=1.0;
 70:   MatGetFactor(mat,MATSOLVERPETSC,MAT_FACTOR_CHOLESKY,&fact);
 71:   MatCholeskyFactorSymbolic(fact,mat,perm,&info);
 72:   MatCholeskyFactorNumeric(fact,mat,&info);

 74:   ISDestroy(&perm);
 75:   MatDestroy(&mat);
 76:   MatDestroy(&fact);
 77:   MatDestroy(&B);
 78:   PetscFinalize();
 79:   return 0;
 80: }