xref: /petsc/src/mat/tests/ex65.c (revision 609caa7c8c030312b00807b4f015fd827bb80932)
1c4762a1bSJed Brown static char help[] = "Saves a rectangular sparse matrix to disk.\n\n";
2c4762a1bSJed Brown 
3c4762a1bSJed Brown #include <petscmat.h>
4c4762a1bSJed Brown 
main(int argc,char ** args)5d71ae5a4SJacob Faibussowitsch int main(int argc, char **args)
6d71ae5a4SJacob Faibussowitsch {
7c4762a1bSJed Brown   Mat         A;
8c4762a1bSJed Brown   PetscInt    m = 100, n = 11, js[11], i, j, cnt;
9c4762a1bSJed Brown   PetscScalar values[11];
10c4762a1bSJed Brown   PetscViewer view;
11c4762a1bSJed Brown 
12327415f7SBarry Smith   PetscFunctionBeginUser;
13c8025a54SPierre Jolivet   PetscCall(PetscInitialize(&argc, &args, NULL, help));
149566063dSJacob Faibussowitsch   PetscCall(MatCreateSeqAIJ(PETSC_COMM_WORLD, m, n, 20, 0, &A));
15c4762a1bSJed Brown 
16c4762a1bSJed Brown   for (i = 0; i < n; i++) values[i] = (PetscReal)i;
17c4762a1bSJed Brown 
18c4762a1bSJed Brown   for (i = 0; i < m; i++) {
19c4762a1bSJed Brown     cnt = 0;
20c4762a1bSJed Brown     if (i % 2) {
21ad540459SPierre Jolivet       for (j = 0; j < n; j += 2) js[cnt++] = j;
22c4762a1bSJed Brown     }
239566063dSJacob Faibussowitsch     PetscCall(MatSetValues(A, 1, &i, cnt, js, values, INSERT_VALUES));
24c4762a1bSJed Brown   }
259566063dSJacob Faibussowitsch   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
269566063dSJacob Faibussowitsch   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
27c4762a1bSJed Brown 
289566063dSJacob Faibussowitsch   PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, "rect", FILE_MODE_WRITE, &view));
299566063dSJacob Faibussowitsch   PetscCall(MatView(A, view));
309566063dSJacob Faibussowitsch   PetscCall(PetscViewerDestroy(&view));
31c4762a1bSJed Brown 
329566063dSJacob Faibussowitsch   PetscCall(MatDestroy(&A));
33c4762a1bSJed Brown 
349566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
35b122ec5aSJacob Faibussowitsch   return 0;
36c4762a1bSJed Brown }
37c4762a1bSJed Brown 
38c4762a1bSJed Brown /*TEST
39c4762a1bSJed Brown 
40c4762a1bSJed Brown    test:
41*3886731fSPierre Jolivet      output_file: output/empty.out
42c4762a1bSJed Brown 
43c4762a1bSJed Brown TEST*/
44