xref: /petsc/src/mat/tests/ex12.c (revision c4762a1b19cd2af06abeed90e8f9d34fb975dd94)
1 
2 static char help[] = "Tests the use of MatZeroRows() for parallel matrices.\n\
3 This example also tests the use of MatDuplicate() for both MPIAIJ and MPIBAIJ matrices";
4 
5 #include <petscmat.h>
6 
7 extern PetscErrorCode TestMatZeroRows_Basic(Mat,IS,PetscScalar);
8 extern PetscErrorCode TestMatZeroRows_with_no_allocation(Mat,IS,PetscScalar);
9 
10 int main(int argc,char **args)
11 {
12   Mat            A;
13   PetscInt       i,j,m = 3,n,Ii,J,Imax;
14   PetscMPIInt    rank,size;
15   PetscErrorCode ierr;
16   PetscScalar    v,diag=-4.0;
17   IS             is;
18 
19   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
20   ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
21   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
22   n    = 2*size;
23 
24   /* create A Square matrix for the five point stencil,YET AGAIN*/
25   ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
26   ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n);CHKERRQ(ierr);
27   ierr = MatSetFromOptions(A);CHKERRQ(ierr);
28   ierr = MatSetUp(A);CHKERRQ(ierr);
29   for (i=0; i<m; i++) {
30     for (j=2*rank; j<2*rank+2; j++) {
31       v = -1.0;  Ii = j + n*i;
32       if (i>0)   {J = Ii - n; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
33       if (i<m-1) {J = Ii + n; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
34       if (j>0)   {J = Ii - 1; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
35       if (j<n-1) {J = Ii + 1; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
36       v = 4.0; ierr = MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES);CHKERRQ(ierr);
37     }
38   }
39   ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
40   ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
41 
42   /* Create AN IS required by MatZeroRows() */
43   Imax = n*rank; if (Imax>= n*m -m - 1) Imax = m*n - m - 1;
44   ierr = ISCreateStride(PETSC_COMM_SELF,m,Imax,1,&is);CHKERRQ(ierr);
45 
46   ierr = TestMatZeroRows_Basic(A,is,0.0);CHKERRQ(ierr);
47   ierr = TestMatZeroRows_Basic(A,is,diag);CHKERRQ(ierr);
48 
49   ierr = TestMatZeroRows_with_no_allocation(A,is,0.0);CHKERRQ(ierr);
50   ierr = TestMatZeroRows_with_no_allocation(A,is,diag);CHKERRQ(ierr);
51 
52   ierr = MatDestroy(&A);CHKERRQ(ierr);
53 
54   /* Now Create a rectangular matrix with five point stencil (app)
55    n+size is used so that this dimension is always divisible by size.
56    This way, we can always use bs = size for any number of procs */
57   ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
58   ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,m*n,m*(n+size));CHKERRQ(ierr);
59   ierr = MatSetFromOptions(A);CHKERRQ(ierr);
60   ierr = MatSetUp(A);CHKERRQ(ierr);
61   for (i=0; i<m; i++) {
62     for (j=2*rank; j<2*rank+2; j++) {
63       v = -1.0;  Ii = j + n*i;
64       if (i>0)   {J = Ii - n; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
65       if (i<m-1) {J = Ii + n; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
66       if (j>0)   {J = Ii - 1; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
67       if (j<n+size-1) {J = Ii + 1; ierr = MatSetValues(A,1,&Ii,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr);}
68       v = 4.0; ierr = MatSetValues(A,1,&Ii,1,&Ii,&v,INSERT_VALUES);CHKERRQ(ierr);
69     }
70   }
71   ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
72   ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
73 
74   ierr = TestMatZeroRows_Basic(A,is,0.0);CHKERRQ(ierr);
75   ierr = TestMatZeroRows_Basic(A,is,diag);CHKERRQ(ierr);
76 
77   ierr = MatDestroy(&A);CHKERRQ(ierr);
78   ierr = ISDestroy(&is);CHKERRQ(ierr);
79   ierr = PetscFinalize();
80   return ierr;
81 }
82 
83 PetscErrorCode TestMatZeroRows_Basic(Mat A,IS is,PetscScalar diag)
84 {
85   Mat            B;
86   PetscErrorCode ierr;
87   PetscBool      keepnonzeropattern;
88 
89   /* Now copy A into B, and test it with MatZeroRows() */
90   ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
91 
92   ierr = PetscOptionsHasName(NULL,NULL,"-keep_nonzero_pattern",&keepnonzeropattern);CHKERRQ(ierr);
93   if (keepnonzeropattern) {
94     ierr = MatSetOption(B,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE);CHKERRQ(ierr);
95   }
96 
97   ierr = MatZeroRowsIS(B,is,diag,0,0);CHKERRQ(ierr);
98   ierr = MatView(B,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
99   ierr = MatDestroy(&B);CHKERRQ(ierr);
100   return 0;
101 }
102 
103 PetscErrorCode TestMatZeroRows_with_no_allocation(Mat A,IS is,PetscScalar diag)
104 {
105   Mat            B;
106   PetscErrorCode ierr;
107 
108   /* Now copy A into B, and test it with MatZeroRows() */
109   ierr = MatDuplicate(A,MAT_COPY_VALUES,&B);CHKERRQ(ierr);
110   /* Set this flag after assembly. This way, it affects only MatZeroRows() */
111   ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
112 
113   ierr = MatZeroRowsIS(B,is,diag,0,0);CHKERRQ(ierr);
114   ierr = MatView(B,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
115   ierr = MatDestroy(&B);CHKERRQ(ierr);
116   return 0;
117 }
118 
119 
120 /*TEST
121 
122    test:
123       nsize: 2
124       filter: grep -v "MPI processes"
125 
126    test:
127       suffix: 2
128       nsize: 3
129       args: -mat_type mpibaij -mat_block_size 3
130       filter: grep -v "MPI processes"
131 
132    test:
133       suffix: 3
134       nsize: 3
135       args: -mat_type mpiaij -keep_nonzero_pattern
136       filter: grep -v "MPI processes"
137 
138    test:
139       suffix: 4
140       nsize: 3
141       args: -keep_nonzero_pattern -mat_type mpibaij -mat_block_size 3
142       filter: grep -v "MPI processes"
143 
144 TEST*/
145