1
2 static char help[]= "Scatters from a sequential vector to a parallel vector. \n\
3 uses block index sets\n\n";
4
5 /* 'mpiexec -n 3 ./ex3 -vecscatter_type mpi3node' might give incorrect solution due to multiple cores write to the same variable */
6
7 #include <petscvec.h>
8
main(int argc,char ** argv)9 int main(int argc,char **argv)
10 {
11 PetscErrorCode ierr;
12 PetscInt bs=1,n=5,i,low;
13 PetscInt ix0[3] = {5,7,9},iy0[3] = {1,2,4},ix1[3] = {2,3,4},iy1[3] = {0,1,3};
14 PetscMPIInt size,rank;
15 PetscScalar *array;
16 Vec x,y;
17 IS isx,isy;
18 VecScatter ctx;
19 PetscViewer sviewer;
20
21 ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
22 ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
23 ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
24
25 if (size <2) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_WRONG_MPI_SIZE,"Must run more than one processor");
26
27 ierr = PetscOptionsGetInt(NULL,NULL,"-bs",&bs,NULL);CHKERRQ(ierr);
28 n = bs*n;
29
30 /* Create vector x over shared memory */
31 ierr = VecCreate(PETSC_COMM_WORLD,&x);CHKERRQ(ierr);
32 ierr = VecSetSizes(x,n,PETSC_DECIDE);CHKERRQ(ierr);
33 ierr = VecSetType(x,VECNODE);CHKERRQ(ierr);
34 ierr = VecSetFromOptions(x);CHKERRQ(ierr);
35
36 ierr = VecGetOwnershipRange(x,&low,NULL);CHKERRQ(ierr);
37 ierr = VecGetArray(x,&array);CHKERRQ(ierr);
38 for (i=0; i<n; i++) {
39 array[i] = (PetscScalar)(i + low);
40 }
41 ierr = VecRestoreArray(x,&array);CHKERRQ(ierr);
42
43 /* Create a sequential vector y */
44 ierr = VecCreateSeq(PETSC_COMM_SELF,n,&y);CHKERRQ(ierr);
45 ierr = VecGetArray(y,&array);CHKERRQ(ierr);
46 for (i=0; i<n; i++) {
47 array[i] = (PetscScalar)(i + 100*rank);
48 }
49 ierr = VecRestoreArray(y,&array);CHKERRQ(ierr);
50
51 /* Create two index sets */
52 if (!rank) {
53 ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,ix0,PETSC_COPY_VALUES,&isx);CHKERRQ(ierr);
54 ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,iy0,PETSC_COPY_VALUES,&isy);CHKERRQ(ierr);
55 } else {
56 ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,ix1,PETSC_COPY_VALUES,&isx);CHKERRQ(ierr);
57 ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,iy1,PETSC_COPY_VALUES,&isy);CHKERRQ(ierr);
58 }
59
60 if (rank == 10) {
61 ierr = PetscPrintf(PETSC_COMM_SELF,"\n[%d] isx:\n",rank);CHKERRQ(ierr);
62 ierr = ISView(isx,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);
63 }
64
65 ierr = VecScatterCreate(y,isy,x,isx,&ctx);CHKERRQ(ierr);
66 ierr = VecScatterSetFromOptions(ctx);CHKERRQ(ierr);
67
68 /* Test forward vecscatter */
69 ierr = VecSet(x,0.0);CHKERRQ(ierr);
70 ierr = VecScatterBegin(ctx,y,x,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
71 ierr = VecScatterEnd(ctx,y,x,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
72 ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
73
74 /* Test reverse vecscatter */
75 ierr = VecScale(x,-1.0);CHKERRQ(ierr);
76 ierr = VecScatterBegin(ctx,x,y,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
77 ierr = VecScatterEnd(ctx,x,y,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
78 ierr = PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr);
79 if (rank == 1) {
80 ierr = VecView(y,sviewer);CHKERRQ(ierr);
81 }
82 ierr = PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr);
83
84 /* Free spaces */
85 ierr = VecScatterDestroy(&ctx);CHKERRQ(ierr);
86 ierr = ISDestroy(&isx);CHKERRQ(ierr);
87 ierr = ISDestroy(&isy);CHKERRQ(ierr);
88 ierr = VecDestroy(&x);CHKERRQ(ierr);
89 ierr = VecDestroy(&y);CHKERRQ(ierr);
90 ierr = PetscFinalize();
91 return ierr;
92 }
93
94 /*TEST
95
96 test:
97 nsize: 2
98 args: -vecscatter_type mpi3node
99 output_file: output/ex3_1.out
100 requires: define(PETSC_HAVE_MPI_PROCESS_SHARED_MEMORY)
101
102 test:
103 suffix: 2
104 nsize: 2
105 args: -vecscatter_type mpi3
106 output_file: output/ex3_1.out
107 requires: define(PETSC_HAVE_MPI_PROCESS_SHARED_MEMORY)
108
109 test:
110 suffix: 3
111 nsize: 2
112 args: -bs 2 -vecscatter_type mpi3node
113 output_file: output/ex3_3.out
114 requires: define(PETSC_HAVE_MPI_PROCESS_SHARED_MEMORY)
115
116 test:
117 suffix: 4
118 nsize: 2
119 args: -bs 2 -vecscatter_type mpi3
120 output_file: output/ex3_3.out
121 requires: define(PETSC_HAVE_MPI_PROCESS_SHARED_MEMORY)
122
123 test:
124 suffix: 5
125 nsize: 3
126 args: -vecscatter_type mpi3
127 output_file: output/ex3_5.out
128 requires: define(PETSC_HAVE_MPI_PROCESS_SHARED_MEMORY)
129
130 TEST*/
131