Actual source code: ex64.c

  1: /*$Id: ex64.c,v 1.16 2001/08/07 03:03:07 balay Exp $*/

  3: static char help[] = "Saves 4by4 block matrix.nn";

 5:  #include petscmat.h

  7: int main(int argc,char **args)
  8: {
  9:   Mat         A;
 10:   int         i,j,ierr,size;
 11:   PetscViewer fd;
 12:   PetscScalar values[16],one = 1.0;
 13:   Vec         x;

 15:   PetscInitialize(&argc,&args,(char *)0,help);
 16:   MPI_Comm_size(PETSC_COMM_WORLD,&size);
 17:   if (size > 1) SETERRQ(1,"Can only run on one processor");

 19:   /* 
 20:      Open binary file.  Note that we use PETSC_BINARY_CREATE to indicate
 21:      writing to this file.
 22:   */
 23:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,"4by4",PETSC_BINARY_CREATE,&fd);

 25:   MatCreateSeqBAIJ(PETSC_COMM_WORLD,4,12,12,0,0,&A);

 27:   for (i=0; i<16; i++) values[i] = i; for (i=0; i<4; i++) values[4*i+i] += 5;
 28:   i = 0; j = 0;
 29:   MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);
 30:   for (i=0; i<16; i++) values[i] = i;
 31:   i = 0; j = 2;
 32:   MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);
 33:   for (i=0; i<16; i++) values[i] = i;
 34:   i = 1; j = 0;
 35:   MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);
 36:   for (i=0; i<16; i++) values[i] = i;for (i=0; i<4; i++) values[4*i+i] += 6;
 37:   i = 1; j = 1;
 38:   MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);
 39:   for (i=0; i<16; i++) values[i] = i;
 40:   i = 2; j = 0;
 41:   MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);
 42:   for (i=0; i<16; i++) values[i] = i;for (i=0; i<4; i++) values[4*i+i] += 7;
 43:   i = 2; j = 2;
 44:   MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);

 46:   MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
 47:   MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
 48:   MatView(A,fd);
 49:   MatDestroy(A);

 51:   VecCreateSeq(PETSC_COMM_WORLD,12,&x);
 52:   VecSet(&one,x);
 53:   VecView(x,fd);
 54:   VecDestroy(x);

 56:   PetscViewerDestroy(fd);
 57:   PetscFinalize();
 58:   return 0;
 59: }