xref: /petsc/src/vec/is/sf/tests/ex11.c (revision 2fa40bb9206b96114faa7cb222621ec184d31cd2)
1 
2 static char help[]= "Scatters between parallel vectors. \n\
3 uses block index sets\n\n";
4 
5 #include <petscvec.h>
6 
7 int main(int argc,char **argv)
8 {
9   PetscErrorCode ierr;
10   PetscInt       bs=1,n=5,N,i,low;
11   PetscInt       ix0[3] = {5,7,9},iy0[3] = {1,2,4},ix1[3] = {2,3,1},iy1[3] = {0,3,9};
12   PetscMPIInt    size,rank;
13   PetscScalar    *array;
14   Vec            x,x1,y;
15   IS             isx,isy;
16   VecScatter     ctx;
17   VecScatterType type;
18   PetscBool      flg;
19 
20   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
21   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRMPI(ierr);
22   ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRMPI(ierr);
23 
24   if (size <2) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_WRONG_MPI_SIZE,"Must run more than one processor");
25 
26   ierr = PetscOptionsGetInt(NULL,NULL,"-bs",&bs,NULL);CHKERRQ(ierr);
27   n    = bs*n;
28 
29   /* Create vector x over shared memory */
30   ierr = VecCreate(PETSC_COMM_WORLD,&x);CHKERRQ(ierr);
31   ierr = VecSetSizes(x,n,PETSC_DECIDE);CHKERRQ(ierr);
32   ierr = VecSetFromOptions(x);CHKERRQ(ierr);
33 
34   ierr = VecGetOwnershipRange(x,&low,NULL);CHKERRQ(ierr);
35   ierr = VecGetArray(x,&array);CHKERRQ(ierr);
36   for (i=0; i<n; i++) {
37     array[i] = (PetscScalar)(i + low);
38   }
39   ierr = VecRestoreArray(x,&array);CHKERRQ(ierr);
40   /* ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); */
41 
42   /* Test some vector functions */
43   ierr = VecAssemblyBegin(x);CHKERRQ(ierr);
44   ierr = VecAssemblyEnd(x);CHKERRQ(ierr);
45 
46   ierr = VecGetSize(x,&N);CHKERRQ(ierr);
47   ierr = VecGetLocalSize(x,&n);CHKERRQ(ierr);
48 
49   ierr = VecDuplicate(x,&x1);CHKERRQ(ierr);
50   ierr = VecCopy(x,x1);CHKERRQ(ierr);
51   ierr = VecEqual(x,x1,&flg);CHKERRQ(ierr);
52   if (!flg) SETERRQ(PetscObjectComm((PetscObject)x),PETSC_ERR_ARG_WRONG,"x1 != x");
53 
54   ierr = VecScale(x1,2.0);CHKERRQ(ierr);
55   ierr = VecSet(x1,10.0);CHKERRQ(ierr);
56   /* ierr = VecView(x1,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); */
57 
58   /* Create vector y over shared memory */
59   ierr = VecCreate(PETSC_COMM_WORLD,&y);CHKERRQ(ierr);
60   ierr = VecSetSizes(y,n,PETSC_DECIDE);CHKERRQ(ierr);
61   ierr = VecSetFromOptions(y);CHKERRQ(ierr);
62   ierr = VecGetArray(y,&array);CHKERRQ(ierr);
63   for (i=0; i<n; i++) {
64     array[i] = -(PetscScalar) (i + 100*rank);
65   }
66   ierr = VecRestoreArray(y,&array);CHKERRQ(ierr);
67   ierr = VecAssemblyBegin(y);CHKERRQ(ierr);
68   ierr = VecAssemblyEnd(y);CHKERRQ(ierr);
69   /* ierr = VecView(y,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); */
70 
71   /* Create two index sets */
72   if (rank == 0) {
73     ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,ix0,PETSC_COPY_VALUES,&isx);CHKERRQ(ierr);
74     ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,iy0,PETSC_COPY_VALUES,&isy);CHKERRQ(ierr);
75   } else {
76     ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,ix1,PETSC_COPY_VALUES,&isx);CHKERRQ(ierr);
77     ierr = ISCreateBlock(PETSC_COMM_SELF,bs,3,iy1,PETSC_COPY_VALUES,&isy);CHKERRQ(ierr);
78   }
79 
80   if (rank == 10) {
81     ierr = PetscPrintf(PETSC_COMM_SELF,"\n[%d] isx:\n",rank);CHKERRQ(ierr);
82     ierr = ISView(isx,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);
83     ierr = PetscPrintf(PETSC_COMM_SELF,"\n[%d] isy:\n",rank);CHKERRQ(ierr);
84     ierr = ISView(isy,PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);
85   }
86 
87   /* Create Vector scatter */
88   ierr = VecScatterCreate(x,isx,y,isy,&ctx);CHKERRQ(ierr);
89   ierr = VecScatterSetFromOptions(ctx);CHKERRQ(ierr);
90   ierr = VecScatterGetType(ctx,&type);CHKERRQ(ierr);
91   ierr = PetscPrintf(PETSC_COMM_WORLD,"scatter type %s\n",type);CHKERRQ(ierr);
92 
93   /* Test forward vecscatter */
94   ierr = VecSet(y,0.0);CHKERRQ(ierr);
95   ierr = VecScatterBegin(ctx,x,y,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
96   ierr = VecScatterEnd(ctx,x,y,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
97   ierr = PetscPrintf(PETSC_COMM_WORLD,"\nSCATTER_FORWARD y:\n");CHKERRQ(ierr);
98   ierr = VecView(y,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
99 
100   /* Test reverse vecscatter */
101   ierr = VecSet(x,0.0);CHKERRQ(ierr);
102   ierr = VecSet(y,0.0);CHKERRQ(ierr);
103   ierr = VecGetOwnershipRange(y,&low,NULL);CHKERRQ(ierr);
104   ierr = VecGetArray(y,&array);CHKERRQ(ierr);
105   for (i=0; i<n; i++) {
106     array[i] = (PetscScalar)(i+ low);
107   }
108   ierr = VecRestoreArray(y,&array);CHKERRQ(ierr);
109   ierr = VecScatterBegin(ctx,y,x,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
110   ierr = VecScatterEnd(ctx,y,x,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
111   ierr = PetscPrintf(PETSC_COMM_WORLD,"\nSCATTER_REVERSE x:\n");CHKERRQ(ierr);
112   ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
113 
114   /* Free objects */
115   ierr = VecScatterDestroy(&ctx);CHKERRQ(ierr);
116   ierr = ISDestroy(&isx);CHKERRQ(ierr);
117   ierr = ISDestroy(&isy);CHKERRQ(ierr);
118   ierr = VecDestroy(&x);CHKERRQ(ierr);
119   ierr = VecDestroy(&x1);CHKERRQ(ierr);
120   ierr = VecDestroy(&y);CHKERRQ(ierr);
121   ierr = PetscFinalize();
122   return ierr;
123 }
124 
125 /*TEST
126 
127    test:
128       nsize: 2
129 
130 TEST*/
131