1: /*$Id: ex5.c,v 1.50 2001/08/07 03:02:34 balay 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: #undef __FUNCT__
 13: int main(int argc,char **args)
 14: {
 15:   int          i,m = 10,rank,size,low,high,ldim,iglobal,ierr;
 16:   PetscScalar  v;
 17:   Vec          u;
 18:   PetscViewer  viewer;
 19:   int          VECTOR_GENERATE,VECTOR_READ;

 21:   PetscInitialize(&argc,&args,(char *)0,help);
 22:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
 23:   MPI_Comm_size(PETSC_COMM_WORLD,&size);
 24:   PetscOptionsGetInt(PETSC_NULL,"-m",&m,PETSC_NULL);

 26:   /* PART 1:  Generate vector, then write it in binary format */

 28:   PetscLogEventRegister(&VECTOR_GENERATE,"Generate Vector",VEC_COOKIE);
 29:   PetscLogEventBegin(VECTOR_GENERATE,0,0,0,0);
 30:   /* Generate vector */
 31:   VecCreate(PETSC_COMM_WORLD,&u);
 32:   VecSetSizes(u,PETSC_DECIDE,m);
 33:   VecSetFromOptions(u);
 34:   VecGetOwnershipRange(u,&low,&high);
 35:   VecGetLocalSize(u,&ldim);
 36:   for (i=0; i<ldim; i++) {
 37:     iglobal = i + low;
 38:     v = (PetscScalar)(i + 100*rank);
 39:     VecSetValues(u,1,&iglobal,&v,INSERT_VALUES);
 40:   }
 41:   VecAssemblyBegin(u);
 42:   VecAssemblyEnd(u);
 43:   VecView(u,PETSC_VIEWER_STDOUT_WORLD);

 45:   PetscPrintf(PETSC_COMM_WORLD,"writing vector in binary to vector.dat ...n");

 47:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,"vector.dat",PETSC_BINARY_CREATE,&viewer);
 48:   VecView(u,viewer);
 49:   PetscViewerDestroy(viewer);
 50:   VecDestroy(u);
 51:   PetscLogEventEnd(VECTOR_GENERATE,0,0,0,0);

 53:   /* PART 2:  Read in vector in binary format */

 55:   /* All processors wait until test vector has been dumped */
 56:   MPI_Barrier(PETSC_COMM_WORLD);
 57:   PetscSleep(10);

 59:   /* Read new vector in binary format */
 60:   PetscLogEventRegister(&VECTOR_READ,"Read Vector",VEC_COOKIE);
 61:   PetscLogEventBegin(VECTOR_READ,0,0,0,0);
 62:   PetscPrintf(PETSC_COMM_WORLD,"reading vector in binary from vector.dat ...n");
 63:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,"vector.dat",PETSC_BINARY_RDONLY,&viewer);
 64:   VecLoad(viewer,&u);
 65:   PetscViewerDestroy(viewer);
 66:   PetscLogEventEnd(VECTOR_READ,0,0,0,0);
 67:   VecView(u,PETSC_VIEWER_STDOUT_WORLD);

 69:   /* Free data structures */
 70:   VecDestroy(u);
 71:   PetscFinalize();
 72:   return 0;
 73: }