xref: /petsc/src/mat/tests/ex181.c (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94) 
1*c4762a1bSJed Brown 
2*c4762a1bSJed Brown static char help[] = "Tests MatCreateSubmatrix() with entire matrix, modified from ex59.c.";
3*c4762a1bSJed Brown 
4*c4762a1bSJed Brown #include <petscmat.h>
5*c4762a1bSJed Brown 
6*c4762a1bSJed Brown int main(int argc,char **args)
7*c4762a1bSJed Brown {
8*c4762a1bSJed Brown   Mat            C,A,Adup;
9*c4762a1bSJed Brown   PetscInt       i,j,m = 3,n = 2,rstart,rend;
10*c4762a1bSJed Brown   PetscMPIInt    size,rank;
11*c4762a1bSJed Brown   PetscErrorCode ierr;
12*c4762a1bSJed Brown   PetscScalar    v;
13*c4762a1bSJed Brown   IS             isrow;
14*c4762a1bSJed Brown   PetscBool      detect_bug = PETSC_FALSE;
15*c4762a1bSJed Brown 
16*c4762a1bSJed Brown   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
17*c4762a1bSJed Brown   ierr = PetscOptionsHasName(NULL,NULL,"-detect_bug",&detect_bug);CHKERRQ(ierr);
18*c4762a1bSJed Brown   ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
19*c4762a1bSJed Brown   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
20*c4762a1bSJed Brown   n    = 2*size;
21*c4762a1bSJed Brown 
22*c4762a1bSJed Brown   ierr = MatCreate(PETSC_COMM_WORLD,&C);CHKERRQ(ierr);
23*c4762a1bSJed Brown   ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n);CHKERRQ(ierr);
24*c4762a1bSJed Brown   ierr = MatSetFromOptions(C);CHKERRQ(ierr);
25*c4762a1bSJed Brown   ierr = MatSetUp(C);CHKERRQ(ierr);
26*c4762a1bSJed Brown 
27*c4762a1bSJed Brown   /*
28*c4762a1bSJed Brown         This is JUST to generate a nice test matrix, all processors fill up
29*c4762a1bSJed Brown     the entire matrix. This is not something one would ever do in practice.
30*c4762a1bSJed Brown   */
31*c4762a1bSJed Brown   ierr = MatGetOwnershipRange(C,&rstart,&rend);CHKERRQ(ierr);
32*c4762a1bSJed Brown   for (i=rstart; i<rend; i++) {
33*c4762a1bSJed Brown     for (j=0; j<m*n; j++) {
34*c4762a1bSJed Brown       v    = i + j + 1;
35*c4762a1bSJed Brown       ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
36*c4762a1bSJed Brown     }
37*c4762a1bSJed Brown   }
38*c4762a1bSJed Brown   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
39*c4762a1bSJed Brown   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
40*c4762a1bSJed Brown   ierr = PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_COMMON);CHKERRQ(ierr);
41*c4762a1bSJed Brown   ierr = MatView(C,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
42*c4762a1bSJed Brown   ierr = PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
43*c4762a1bSJed Brown 
44*c4762a1bSJed Brown   /*
45*c4762a1bSJed Brown      Generate a new matrix consisting every row and column of the original matrix
46*c4762a1bSJed Brown   */
47*c4762a1bSJed Brown   ierr = MatGetOwnershipRange(C,&rstart,&rend);CHKERRQ(ierr);
48*c4762a1bSJed Brown 
49*c4762a1bSJed Brown   /* Create parallel IS with the rows we want on THIS processor */
50*c4762a1bSJed Brown   if (detect_bug && !rank) {
51*c4762a1bSJed Brown     ierr = ISCreateStride(PETSC_COMM_WORLD,1,rstart,1,&isrow);CHKERRQ(ierr);
52*c4762a1bSJed Brown   } else {
53*c4762a1bSJed Brown     ierr = ISCreateStride(PETSC_COMM_WORLD,rend-rstart,rstart,1,&isrow);CHKERRQ(ierr);
54*c4762a1bSJed Brown   }
55*c4762a1bSJed Brown   ierr = MatCreateSubMatrix(C,isrow,NULL,MAT_INITIAL_MATRIX,&A);CHKERRQ(ierr);
56*c4762a1bSJed Brown 
57*c4762a1bSJed Brown   /* Change C to test the case MAT_REUSE_MATRIX */
58*c4762a1bSJed Brown   if (!rank ) {
59*c4762a1bSJed Brown     i = 0; j = 0; v = 100;
60*c4762a1bSJed Brown     ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
61*c4762a1bSJed Brown   }
62*c4762a1bSJed Brown   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
63*c4762a1bSJed Brown   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
64*c4762a1bSJed Brown 
65*c4762a1bSJed Brown   ierr = MatCreateSubMatrix(C,isrow,NULL,MAT_REUSE_MATRIX,&A);CHKERRQ(ierr);
66*c4762a1bSJed Brown   ierr = PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_COMMON);CHKERRQ(ierr);
67*c4762a1bSJed Brown   ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
68*c4762a1bSJed Brown   ierr = PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
69*c4762a1bSJed Brown 
70*c4762a1bSJed Brown   /* Test MatDuplicate */
71*c4762a1bSJed Brown   ierr = MatDuplicate(A,MAT_COPY_VALUES,&Adup);CHKERRQ(ierr);
72*c4762a1bSJed Brown   ierr = MatDestroy(&Adup);CHKERRQ(ierr);
73*c4762a1bSJed Brown 
74*c4762a1bSJed Brown   ierr = ISDestroy(&isrow);CHKERRQ(ierr);
75*c4762a1bSJed Brown   ierr = MatDestroy(&A);CHKERRQ(ierr);
76*c4762a1bSJed Brown   ierr = MatDestroy(&C);CHKERRQ(ierr);
77*c4762a1bSJed Brown   ierr = PetscFinalize();
78*c4762a1bSJed Brown   return ierr;
79*c4762a1bSJed Brown }
80*c4762a1bSJed Brown 
81*c4762a1bSJed Brown 
82*c4762a1bSJed Brown /*TEST
83*c4762a1bSJed Brown 
84*c4762a1bSJed Brown    test:
85*c4762a1bSJed Brown       nsize: 2
86*c4762a1bSJed Brown       filter: grep -v "Mat Object"
87*c4762a1bSJed Brown       requires: !complex
88*c4762a1bSJed Brown 
89*c4762a1bSJed Brown    test:
90*c4762a1bSJed Brown       suffix: 2
91*c4762a1bSJed Brown       nsize: 3
92*c4762a1bSJed Brown       args: -detect_bug
93*c4762a1bSJed Brown       filter: grep -v "Mat Object"
94*c4762a1bSJed Brown       requires: !complex
95*c4762a1bSJed Brown 
96*c4762a1bSJed Brown TEST*/
97