Actual source code: ex21.c
1: /*$Id: ex21.c,v 1.22 2001/08/07 03:03:07 balay Exp $*/
3: static char help[] = "Tests converting a parallel AIJ formatted matrix to the parallel Row format.n
4: This also tests MatGetRow() and MatRestoreRow() for the parallel case.nn";
6: #include petscmat.h
8: int main(int argc,char **args)
9: {
10: Mat C,A;
11: int i,j,m = 3,n = 2,rank,size,I,J,ierr,rstart,rend,nz,*idx;
12: PetscScalar v,*values;
14: PetscInitialize(&argc,&args,(char *)0,help);
15: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
16: MPI_Comm_size(PETSC_COMM_WORLD,&size);
17: n = 2*size;
19: /* create the matrix for the five point stencil, YET AGAIN*/
20: MatCreate(PETSC_COMM_WORLD,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n,&C);
21: MatSetFromOptions(C);
22: MatMPIAIJSetPreallocation(C,5,PETSC_NULL,5,PETSC_NULL);
23: MatSeqAIJSetPreallocation(C,5,PETSC_NULL);
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: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO);
37: MatView(C,PETSC_VIEWER_STDOUT_WORLD);
38: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
39: MatView(C,PETSC_VIEWER_STDOUT_WORLD);
41: MatGetOwnershipRange(C,&rstart,&rend);
42: for (i=rstart; i<rend; i++) {
43: MatGetRow(C,i,&nz,&idx,&values);
44: PetscSynchronizedFPrintf(PETSC_COMM_WORLD,stdout,"[%d] get row %d: ",rank,i);
45: for (j=0; j<nz; j++) {
46: #if defined(PETSC_USE_COMPLEX)
47: PetscSynchronizedFPrintf(PETSC_COMM_WORLD,stdout,"%d %g ",idx[j],PetscRealPart(values[j]));
48: #else
49: PetscSynchronizedFPrintf(PETSC_COMM_WORLD,stdout,"%d %g ",idx[j],values[j]);
50: #endif
51: }
52: PetscSynchronizedFPrintf(PETSC_COMM_WORLD,stdout,"n");
53: MatRestoreRow(C,i,&nz,&idx,&values);
54: }
55: PetscSynchronizedFlush(PETSC_COMM_WORLD);
57: MatConvert(C,MATSAME,&A);
58: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO);
59: MatView(A,PETSC_VIEWER_STDOUT_WORLD);
60: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
61: MatView(A,PETSC_VIEWER_STDOUT_WORLD);
63: MatDestroy(A);
64: MatDestroy(C);
65: PetscFinalize();
66: return 0;
67: }