1c4762a1bSJed Brown static char help[] = "This program illustrates the use of PETSc-fftw interface for real DFT\n"; 2c4762a1bSJed Brown #include <petscmat.h> 3c4762a1bSJed Brown #include <fftw3-mpi.h> 4c4762a1bSJed Brown 5c4762a1bSJed Brown extern PetscErrorCode InputTransformFFT(Mat, Vec, Vec); 6c4762a1bSJed Brown extern PetscErrorCode OutputTransformFFT(Mat, Vec, Vec); 7*d71ae5a4SJacob Faibussowitsch int main(int argc, char **args) 8*d71ae5a4SJacob Faibussowitsch { 9c4762a1bSJed Brown PetscMPIInt rank, size; 10c4762a1bSJed Brown PetscInt N0 = 3, N1 = 3, N2 = 3, N = N0 * N1 * N2; 11c4762a1bSJed Brown PetscRandom rdm; 12c4762a1bSJed Brown PetscScalar a; 13c4762a1bSJed Brown PetscReal enorm; 14c4762a1bSJed Brown Vec x, y, z, input, output; 15c4762a1bSJed Brown PetscBool view = PETSC_FALSE, use_interface = PETSC_TRUE; 16c4762a1bSJed Brown Mat A; 17c4762a1bSJed Brown PetscInt DIM, dim[3], vsize; 18c4762a1bSJed Brown PetscReal fac; 19c4762a1bSJed Brown 20327415f7SBarry Smith PetscFunctionBeginUser; 219566063dSJacob Faibussowitsch PetscCall(PetscInitialize(&argc, &args, (char *)0, help)); 22c4762a1bSJed Brown #if defined(PETSC_USE_COMPLEX) 23c4762a1bSJed Brown SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_SUP, "This example requires real numbers"); 24c4762a1bSJed Brown #endif 25c4762a1bSJed Brown 269566063dSJacob Faibussowitsch PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size)); 279566063dSJacob Faibussowitsch PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank)); 28c4762a1bSJed Brown 299566063dSJacob Faibussowitsch PetscCall(PetscRandomCreate(PETSC_COMM_WORLD, &rdm)); 309566063dSJacob Faibussowitsch PetscCall(PetscRandomSetFromOptions(rdm)); 31c4762a1bSJed Brown 329566063dSJacob Faibussowitsch PetscCall(VecCreate(PETSC_COMM_WORLD, &input)); 339566063dSJacob Faibussowitsch PetscCall(VecSetSizes(input, PETSC_DECIDE, N)); 349566063dSJacob Faibussowitsch PetscCall(VecSetFromOptions(input)); 359566063dSJacob Faibussowitsch PetscCall(VecSetRandom(input, rdm)); 369566063dSJacob Faibussowitsch PetscCall(VecDuplicate(input, &output)); 379566063dSJacob Faibussowitsch /* PetscCall(VecGetSize(input,&vsize)); */ 38c4762a1bSJed Brown /* printf("Size of the input Vector is %d\n",vsize); */ 39c4762a1bSJed Brown 40c4762a1bSJed Brown DIM = 3; 419371c9d4SSatish Balay dim[0] = N0; 429371c9d4SSatish Balay dim[1] = N1; 439371c9d4SSatish Balay dim[2] = N2; 44c4762a1bSJed Brown 459566063dSJacob Faibussowitsch PetscCall(MatCreateFFT(PETSC_COMM_WORLD, DIM, dim, MATFFTW, &A)); 469566063dSJacob Faibussowitsch PetscCall(MatCreateVecs(A, &x, &y)); 479566063dSJacob Faibussowitsch PetscCall(MatCreateVecs(A, &z, NULL)); 489566063dSJacob Faibussowitsch PetscCall(VecGetSize(y, &vsize)); 49c4762a1bSJed Brown printf("The vector size from the main routine is %d\n", vsize); 50c4762a1bSJed Brown 519566063dSJacob Faibussowitsch PetscCall(InputTransformFFT(A, input, x)); 529566063dSJacob Faibussowitsch PetscCall(MatMult(A, x, y)); 539566063dSJacob Faibussowitsch PetscCall(MatMultTranspose(A, y, z)); 549566063dSJacob Faibussowitsch PetscCall(OutputTransformFFT(A, z, output)); 55c4762a1bSJed Brown 56c4762a1bSJed Brown fac = 1.0 / (PetscReal)N; 579566063dSJacob Faibussowitsch PetscCall(VecScale(output, fac)); 58c4762a1bSJed Brown 599566063dSJacob Faibussowitsch PetscCall(VecAssemblyBegin(input)); 609566063dSJacob Faibussowitsch PetscCall(VecAssemblyEnd(input)); 619566063dSJacob Faibussowitsch PetscCall(VecAssemblyBegin(output)); 629566063dSJacob Faibussowitsch PetscCall(VecAssemblyEnd(output)); 63c4762a1bSJed Brown 649566063dSJacob Faibussowitsch PetscCall(VecView(input, PETSC_VIEWER_STDOUT_WORLD)); 659566063dSJacob Faibussowitsch PetscCall(VecView(output, PETSC_VIEWER_STDOUT_WORLD)); 66c4762a1bSJed Brown 679566063dSJacob Faibussowitsch PetscCall(VecAXPY(output, -1.0, input)); 689566063dSJacob Faibussowitsch PetscCall(VecNorm(output, NORM_1, &enorm)); 69c4762a1bSJed Brown /* if (enorm > 1.e-14) { */ 7048a46eb9SPierre Jolivet if (rank == 0) PetscCall(PetscPrintf(PETSC_COMM_SELF, " Error norm of |x - z| %e\n", enorm)); 71c4762a1bSJed Brown /* } */ 72c4762a1bSJed Brown 739566063dSJacob Faibussowitsch /* PetscCall(MatCreateVecs(A,&z,NULL)); */ 74c4762a1bSJed Brown /* printf("Vector size from ex148 %d\n",vsize); */ 759566063dSJacob Faibussowitsch /* PetscCall(PetscObjectSetName((PetscObject) x, "Real space vector")); */ 769566063dSJacob Faibussowitsch /* PetscCall(PetscObjectSetName((PetscObject) y, "Frequency space vector")); */ 779566063dSJacob Faibussowitsch /* PetscCall(PetscObjectSetName((PetscObject) z, "Reconstructed vector")); */ 78c4762a1bSJed Brown 799566063dSJacob Faibussowitsch PetscCall(PetscFinalize()); 80b122ec5aSJacob Faibussowitsch return 0; 81c4762a1bSJed Brown } 82