xref: /petsc/src/mat/tests/ex64.c (revision 2c71b3e237ead271e4f3aa1505f92bf476e3413d)
1c4762a1bSJed Brown 
2c4762a1bSJed Brown static char help[] = "Saves 4by4 block matrix.\n\n";
3c4762a1bSJed Brown 
4c4762a1bSJed Brown #include <petscmat.h>
5c4762a1bSJed Brown 
6c4762a1bSJed Brown int main(int argc,char **args)
7c4762a1bSJed Brown {
8c4762a1bSJed Brown   Mat            A;
9c4762a1bSJed Brown   PetscInt       i,j;
10c4762a1bSJed Brown   PetscErrorCode ierr;
11c4762a1bSJed Brown   PetscMPIInt    size;
12c4762a1bSJed Brown   PetscViewer    fd;
13c4762a1bSJed Brown   PetscScalar    values[16],one = 1.0;
14c4762a1bSJed Brown   Vec            x;
15c4762a1bSJed Brown 
16c4762a1bSJed Brown   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
17ffc4695bSBarry Smith   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRMPI(ierr);
18*2c71b3e2SJacob Faibussowitsch   PetscCheckFalse(size > 1,PETSC_COMM_WORLD,PETSC_ERR_WRONG_MPI_SIZE,m"Can only run on one processor");
19c4762a1bSJed Brown 
20c4762a1bSJed Brown   /*
21c4762a1bSJed Brown      Open binary file.  Note that we use FILE_MODE_WRITE to indicate
22c4762a1bSJed Brown      writing to this file.
23c4762a1bSJed Brown   */
24c4762a1bSJed Brown   ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,"4by4",FILE_MODE_WRITE,&fd);CHKERRQ(ierr);
25c4762a1bSJed Brown 
26c4762a1bSJed Brown   ierr = MatCreateSeqBAIJ(PETSC_COMM_WORLD,4,12,12,0,0,&A);CHKERRQ(ierr);
27c4762a1bSJed Brown 
28c4762a1bSJed Brown   for (i=0; i<16; i++) values[i] = i;
29c4762a1bSJed Brown   for (i=0; i<4; i++) values[4*i+i] += 5;
30c4762a1bSJed Brown   i    = 0; j = 0;
31c4762a1bSJed Brown   ierr = MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);CHKERRQ(ierr);
32c4762a1bSJed Brown 
33c4762a1bSJed Brown   for (i=0; i<16; i++) values[i] = i;
34c4762a1bSJed Brown   i    = 0; j = 2;
35c4762a1bSJed Brown   ierr = MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);CHKERRQ(ierr);
36c4762a1bSJed Brown 
37c4762a1bSJed Brown   for (i=0; i<16; i++) values[i] = i;
38c4762a1bSJed Brown   i    = 1; j = 0;
39c4762a1bSJed Brown   ierr = MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);CHKERRQ(ierr);
40c4762a1bSJed Brown 
41c4762a1bSJed Brown   for (i=0; i<16; i++) values[i] = i;for (i=0; i<4; i++) values[4*i+i] += 6;
42c4762a1bSJed Brown   i    = 1; j = 1;
43c4762a1bSJed Brown   ierr = MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);CHKERRQ(ierr);
44c4762a1bSJed Brown 
45c4762a1bSJed Brown   for (i=0; i<16; i++) values[i] = i;
46c4762a1bSJed Brown   i    = 2; j = 0;
47c4762a1bSJed Brown   ierr = MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);CHKERRQ(ierr);
48c4762a1bSJed Brown 
49c4762a1bSJed Brown   for (i=0; i<16; i++) values[i] = i;for (i=0; i<4; i++) values[4*i+i] += 7;
50c4762a1bSJed Brown   i    = 2; j = 2;
51c4762a1bSJed Brown   ierr = MatSetValuesBlocked(A,1,&i,1,&j,values,INSERT_VALUES);CHKERRQ(ierr);
52c4762a1bSJed Brown 
53c4762a1bSJed Brown   ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
54c4762a1bSJed Brown   ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
55c4762a1bSJed Brown   ierr = MatView(A,fd);CHKERRQ(ierr);
56c4762a1bSJed Brown   ierr = MatDestroy(&A);CHKERRQ(ierr);
57c4762a1bSJed Brown 
58c4762a1bSJed Brown   ierr = VecCreateSeq(PETSC_COMM_WORLD,12,&x);CHKERRQ(ierr);
59c4762a1bSJed Brown   ierr = VecSet(x,one);CHKERRQ(ierr);
60c4762a1bSJed Brown   ierr = VecView(x,fd);CHKERRQ(ierr);
61c4762a1bSJed Brown   ierr = VecDestroy(&x);CHKERRQ(ierr);
62c4762a1bSJed Brown 
63c4762a1bSJed Brown   ierr = PetscViewerDestroy(&fd);CHKERRQ(ierr);
64c4762a1bSJed Brown   ierr = PetscFinalize();
65c4762a1bSJed Brown   return ierr;
66c4762a1bSJed Brown }
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