Actual source code: ex108.c

  1: static char help[] = "Testing MatCreateSeqBAIJWithArrays() and MatCreateSeqSBAIJWithArrays().\n\n";

  3: #include <petscmat.h>

  5: int main(int argc,char **argv)
  6: {
  7:   Mat            A,B,As;
  8:   const PetscInt *ai,*aj;
  9:   PetscInt       i,j,k,nz,n,asi[]={0,2,3,4,6,7};
 10:   PetscInt       asj[]={0,4,1,2,3,4,4};
 11:   PetscScalar    asa[7],*aa;
 12:   PetscRandom    rctx;
 13:   PetscMPIInt    size;
 14:   PetscBool      flg;

 16:   PetscInitialize(&argc,&argv,(char*)0,help);
 17:   MPI_Comm_size(PETSC_COMM_WORLD,&size);

 20:   /* Create a aij matrix for checking */
 21:   MatCreateSeqAIJ(PETSC_COMM_SELF,5,5,2,NULL,&A);
 22:   PetscRandomCreate(PETSC_COMM_WORLD,&rctx);
 23:   PetscRandomSetFromOptions(rctx);

 25:   k = 0;
 26:   for (i=0; i<5; i++) {
 27:     nz = asi[i+1] - asi[i];  /* length of i_th row of A */
 28:     for (j=0; j<nz; j++) {
 29:       PetscRandomGetValue(rctx,&asa[k]);
 30:       MatSetValues(A,1,&i,1,&asj[k],&asa[k],INSERT_VALUES);
 31:       MatSetValues(A,1,&i,1,&asj[k],&asa[k],INSERT_VALUES);
 32:       if (i != asj[k]) { /* insert symmetric entry */
 33:         MatSetValues(A,1,&asj[k],1,&i,&asa[k],INSERT_VALUES);
 34:       }
 35:       k++;
 36:     }
 37:   }
 38:   MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
 39:   MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);

 41:   /* Create a baij matrix using MatCreateSeqBAIJWithArrays() */
 42:   MatGetRowIJ(A,0,PETSC_FALSE,PETSC_FALSE,&n,&ai,&aj,&flg);
 43:   MatSeqAIJGetArray(A,&aa);
 44:   /* WARNING: This sharing is dangerous if either A or B is later assembled */
 45:   MatCreateSeqBAIJWithArrays(PETSC_COMM_SELF,1,5,5,(PetscInt*)ai,(PetscInt*)aj,aa,&B);
 46:   MatSeqAIJRestoreArray(A,&aa);
 47:   MatRestoreRowIJ(A,0,PETSC_FALSE,PETSC_FALSE,&n,&ai,&aj,&flg);
 48:   MatMultEqual(A,B,10,&flg);

 51:   /* Create a sbaij matrix using MatCreateSeqSBAIJWithArrays() */
 52:   MatCreateSeqSBAIJWithArrays(PETSC_COMM_SELF,1,5,5,asi,asj,asa,&As);
 53:   MatMultEqual(A,As,10,&flg);

 56:   /* Free spaces */
 57:   PetscRandomDestroy(&rctx);
 58:   MatDestroy(&A);
 59:   MatDestroy(&B);
 60:   MatDestroy(&As);
 61:   PetscFinalize();
 62:   return 0;
 63: }