1 2 static char help[] = "Tests binary I/O of vectors and illustrates the use of user-defined event logging.\n\n"; 3 4 #include <petscvec.h> 5 6 /* Note: Most applications would not read and write a vector within 7 the same program. This example is intended only to demonstrate 8 both input and output. */ 9 10 int main(int argc,char **args) 11 { 12 PetscMPIInt rank,size; 13 PetscInt i,m = 10,low,high,ldim,iglobal; 14 PetscScalar v; 15 Vec u; 16 PetscViewer viewer; 17 #if defined(PETSC_USE_LOG) 18 PetscLogEvent VECTOR_GENERATE,VECTOR_READ; 19 #endif 20 21 PetscFunctionBeginUser; 22 PetscCall(PetscInitialize(&argc,&args,(char*)0,help)); 23 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank)); 24 PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size)); 25 PetscCall(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL)); 26 27 /* PART 1: Generate vector, then write it in binary format */ 28 29 PetscCall(PetscLogEventRegister("Generate Vector",VEC_CLASSID,&VECTOR_GENERATE)); 30 PetscCall(PetscLogEventBegin(VECTOR_GENERATE,0,0,0,0)); 31 /* Generate vector */ 32 PetscCall(VecCreate(PETSC_COMM_WORLD,&u)); 33 PetscCall(VecSetSizes(u,PETSC_DECIDE,m)); 34 PetscCall(VecSetFromOptions(u)); 35 PetscCall(VecGetOwnershipRange(u,&low,&high)); 36 PetscCall(VecGetLocalSize(u,&ldim)); 37 for (i=0; i<ldim; i++) { 38 iglobal = i + low; 39 v = (PetscScalar)(i + 100*rank); 40 PetscCall(VecSetValues(u,1,&iglobal,&v,INSERT_VALUES)); 41 } 42 PetscCall(VecAssemblyBegin(u)); 43 PetscCall(VecAssemblyEnd(u)); 44 PetscCall(VecView(u,PETSC_VIEWER_STDOUT_WORLD)); 45 46 PetscCall(PetscPrintf(PETSC_COMM_WORLD,"writing vector in binary to vector.dat ...\n")); 47 PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,"vector.dat",FILE_MODE_WRITE,&viewer)); 48 PetscCall(VecView(u,viewer)); 49 PetscCall(PetscViewerDestroy(&viewer)); 50 PetscCall(VecDestroy(&u)); 51 PetscCall(PetscOptionsSetValue(NULL,"-viewer_binary_mpiio","")); 52 53 PetscCall(PetscLogEventEnd(VECTOR_GENERATE,0,0,0,0)); 54 55 /* PART 2: Read in vector in binary format */ 56 57 /* Read new vector in binary format */ 58 PetscCall(PetscLogEventRegister("Read Vector",VEC_CLASSID,&VECTOR_READ)); 59 PetscCall(PetscLogEventBegin(VECTOR_READ,0,0,0,0)); 60 PetscCall(PetscPrintf(PETSC_COMM_WORLD,"reading vector in binary from vector.dat ...\n")); 61 PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,"vector.dat",FILE_MODE_READ,&viewer)); 62 PetscCall(VecCreate(PETSC_COMM_WORLD,&u)); 63 PetscCall(VecLoad(u,viewer)); 64 PetscCall(PetscViewerDestroy(&viewer)); 65 PetscCall(PetscLogEventEnd(VECTOR_READ,0,0,0,0)); 66 PetscCall(VecView(u,PETSC_VIEWER_STDOUT_WORLD)); 67 68 /* Free data structures */ 69 PetscCall(VecDestroy(&u)); 70 PetscCall(PetscFinalize()); 71 return 0; 72 } 73 74 /*TEST 75 76 test: 77 nsize: 1 78 requires: mpiio 79 80 test: 81 suffix: 2 82 nsize: 2 83 requires: mpiio 84 85 TEST*/ 86