Actual source code: ex60.c

  1: /*$Id: ex60.c,v 1.15 2001/09/11 16:32:50 bsmith Exp $*/

  3: static char help[] = "Tests MatGetColumnVector().";

 5:  #include petscmat.h

  7: int main(int argc,char **args)
  8: {
  9:   Mat         C;
 10:   int         i,j,m = 3,n = 2,rank,size,I,J,ierr,col = 0;
 11:   PetscScalar v;
 12:   Vec         yy;

 14:   PetscInitialize(&argc,&args,(char *)0,help);
 15:   PetscOptionsGetInt(PETSC_NULL,"-col",&col,PETSC_NULL);

 17:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
 18:   MPI_Comm_size(PETSC_COMM_WORLD,&size);
 19:   n = 2*size;

 21:   /* create the matrix for the five point stencil, YET AGAIN*/
 22:   MatCreateMPIAIJ(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,
 23:          m*n,m*n,5,PETSC_NULL,5,PETSC_NULL,&C);
 24:   for (i=0; i<m; i++) {
 25:     for (j=2*rank; j<2*rank+2; j++) {
 26:       v = -1.0;  I = j + n*i;
 27:       if (i>0)   {J = I - n; MatSetValues(C,1,&I,1,&J,&v,INSERT_VALUES);}
 28:       if (i<m-1) {J = I + n; MatSetValues(C,1,&I,1,&J,&v,INSERT_VALUES);}
 29:       if (j>0)   {J = I - 1; MatSetValues(C,1,&I,1,&J,&v,INSERT_VALUES);}
 30:       if (j<n-1) {J = I + 1; MatSetValues(C,1,&I,1,&J,&v,INSERT_VALUES);}
 31:       v = 4.0; MatSetValues(C,1,&I,1,&I,&v,INSERT_VALUES);
 32:     }
 33:   }
 34:   MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);
 35:   MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);
 36:   MatView(C,PETSC_VIEWER_STDOUT_WORLD);

 38:   VecCreate(PETSC_COMM_WORLD,&yy);
 39:   VecSetSizes(yy,PETSC_DECIDE,m*n);
 40:   VecSetFromOptions(yy);

 42:   MatGetColumnVector(C,yy,col);

 44:   VecView(yy,PETSC_VIEWER_STDOUT_WORLD);

 46:   VecDestroy(yy);
 47:   MatDestroy(C);
 48:   PetscFinalize();
 49:   return 0;
 50: }