Actual source code: ex5.c
1: /*$Id: ex5.c,v 1.48 2001/04/10 19:35:06 bsmith Exp $*/
3: static char help[] = "Tests binary I/O of vectors and illustrates the use of user-defined event logging.nn";
5: #include petscvec.h
7: /* Note: Most applications would not read and write a vector within
8: the same program. This example is intended only to demonstrate
9: both input and output. */
11: int main(int argc,char **args)
12: {
13: int i,m = 10,rank,size,low,high,ldim,iglobal,ierr;
14: Scalar v;
15: Vec u;
16: PetscViewer viewer;
17: int VECTOR_GENERATE,VECTOR_READ;
19: PetscInitialize(&argc,&args,(char *)0,help);
20: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
21: MPI_Comm_size(PETSC_COMM_WORLD,&size);
22: PetscOptionsGetInt(PETSC_NULL,"-m",&m,PETSC_NULL);
24: /* PART 1: Generate vector, then write it in binary format */
26: PetscLogEventRegister(&VECTOR_GENERATE,"Generate Vector","Red:");
27: PetscLogEventBegin(VECTOR_GENERATE,0,0,0,0);
28: /* Generate vector */
29: VecCreate(PETSC_COMM_WORLD,PETSC_DECIDE,m,&u);
30: VecSetFromOptions(u);
31: VecGetOwnershipRange(u,&low,&high);
32: VecGetLocalSize(u,&ldim);
33: for (i=0; i<ldim; i++) {
34: iglobal = i + low;
35: v = (Scalar)(i + 100*rank);
36: VecSetValues(u,1,&iglobal,&v,INSERT_VALUES);
37: }
38: VecAssemblyBegin(u);
39: VecAssemblyEnd(u);
40: VecView(u,PETSC_VIEWER_STDOUT_WORLD);
42: PetscPrintf(PETSC_COMM_WORLD,"writing vector in binary to vector.dat ...n");
44: PetscViewerBinaryOpen(PETSC_COMM_WORLD,"vector.dat",PETSC_BINARY_CREATE,&viewer);
45: VecView(u,viewer);
46: PetscViewerDestroy(viewer);
47: VecDestroy(u);
48: PetscLogEventEnd(VECTOR_GENERATE,0,0,0,0);
50: /* PART 2: Read in vector in binary format */
52: /* All processors wait until test vector has been dumped */
53: MPI_Barrier(PETSC_COMM_WORLD);
54: PetscSleep(10);
56: /* Read new vector in binary format */
57: PetscLogEventRegister(&VECTOR_READ,"Read Vector","Green:");
58: PetscLogEventBegin(VECTOR_READ,0,0,0,0);
59: PetscPrintf(PETSC_COMM_WORLD,"reading vector in binary from vector.dat ...n");
60: PetscViewerBinaryOpen(PETSC_COMM_WORLD,"vector.dat",PETSC_BINARY_RDONLY,&viewer);
61: VecLoad(viewer,&u);
62: PetscViewerDestroy(viewer);
63: PetscLogEventEnd(VECTOR_READ,0,0,0,0);
64: VecView(u,PETSC_VIEWER_STDOUT_WORLD);
66: /* Free data structures */
67: VecDestroy(u);
68: PetscFinalize();
69: return 0;
70: }