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); 7ad0e0ea3SStefano Zampini int main(int argc,char **args) 8c4762a1bSJed Brown { 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 20*b122ec5aSJacob Faibussowitsch CHKERRQ(PetscInitialize(&argc,&args,(char*)0,help)); 21c4762a1bSJed Brown #if defined(PETSC_USE_COMPLEX) 22c4762a1bSJed Brown SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP, "This example requires real numbers"); 23c4762a1bSJed Brown #endif 24c4762a1bSJed Brown 255f80ce2aSJacob Faibussowitsch CHKERRMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size)); 265f80ce2aSJacob Faibussowitsch CHKERRMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank)); 27c4762a1bSJed Brown 285f80ce2aSJacob Faibussowitsch CHKERRQ(PetscRandomCreate(PETSC_COMM_WORLD, &rdm)); 295f80ce2aSJacob Faibussowitsch CHKERRQ(PetscRandomSetFromOptions(rdm)); 30c4762a1bSJed Brown 315f80ce2aSJacob Faibussowitsch CHKERRQ(VecCreate(PETSC_COMM_WORLD,&input)); 325f80ce2aSJacob Faibussowitsch CHKERRQ(VecSetSizes(input,PETSC_DECIDE,N)); 335f80ce2aSJacob Faibussowitsch CHKERRQ(VecSetFromOptions(input)); 345f80ce2aSJacob Faibussowitsch CHKERRQ(VecSetRandom(input,rdm)); 355f80ce2aSJacob Faibussowitsch CHKERRQ(VecDuplicate(input,&output)); 365f80ce2aSJacob Faibussowitsch /* CHKERRQ(VecGetSize(input,&vsize)); */ 37c4762a1bSJed Brown /* printf("Size of the input Vector is %d\n",vsize); */ 38c4762a1bSJed Brown 39c4762a1bSJed Brown DIM = 3; 40c4762a1bSJed Brown dim[0] = N0; dim[1] = N1; dim[2] = N2; 41c4762a1bSJed Brown 425f80ce2aSJacob Faibussowitsch CHKERRQ(MatCreateFFT(PETSC_COMM_WORLD,DIM,dim,MATFFTW,&A)); 435f80ce2aSJacob Faibussowitsch CHKERRQ(MatCreateVecs(A,&x,&y)); 445f80ce2aSJacob Faibussowitsch CHKERRQ(MatCreateVecs(A,&z,NULL)); 455f80ce2aSJacob Faibussowitsch CHKERRQ(VecGetSize(y,&vsize)); 46c4762a1bSJed Brown printf("The vector size from the main routine is %d\n",vsize); 47c4762a1bSJed Brown 485f80ce2aSJacob Faibussowitsch CHKERRQ(InputTransformFFT(A,input,x)); 495f80ce2aSJacob Faibussowitsch CHKERRQ(MatMult(A,x,y)); 505f80ce2aSJacob Faibussowitsch CHKERRQ(MatMultTranspose(A,y,z)); 515f80ce2aSJacob Faibussowitsch CHKERRQ(OutputTransformFFT(A,z,output)); 52c4762a1bSJed Brown 53c4762a1bSJed Brown fac = 1.0/(PetscReal)N; 545f80ce2aSJacob Faibussowitsch CHKERRQ(VecScale(output,fac)); 55c4762a1bSJed Brown 565f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyBegin(input)); 575f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyEnd(input)); 585f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyBegin(output)); 595f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyEnd(output)); 60c4762a1bSJed Brown 615f80ce2aSJacob Faibussowitsch CHKERRQ(VecView(input,PETSC_VIEWER_STDOUT_WORLD)); 625f80ce2aSJacob Faibussowitsch CHKERRQ(VecView(output,PETSC_VIEWER_STDOUT_WORLD)); 63c4762a1bSJed Brown 645f80ce2aSJacob Faibussowitsch CHKERRQ(VecAXPY(output,-1.0,input)); 655f80ce2aSJacob Faibussowitsch CHKERRQ(VecNorm(output,NORM_1,&enorm)); 66c4762a1bSJed Brown /* if (enorm > 1.e-14) { */ 67dd400576SPatrick Sanan if (rank == 0) { 685f80ce2aSJacob Faibussowitsch CHKERRQ(PetscPrintf(PETSC_COMM_SELF," Error norm of |x - z| %e\n",enorm)); 69c4762a1bSJed Brown } 70c4762a1bSJed Brown /* } */ 71c4762a1bSJed Brown 725f80ce2aSJacob Faibussowitsch /* CHKERRQ(MatCreateVecs(A,&z,NULL)); */ 73c4762a1bSJed Brown /* printf("Vector size from ex148 %d\n",vsize); */ 745f80ce2aSJacob Faibussowitsch /* CHKERRQ(PetscObjectSetName((PetscObject) x, "Real space vector")); */ 755f80ce2aSJacob Faibussowitsch /* CHKERRQ(PetscObjectSetName((PetscObject) y, "Frequency space vector")); */ 765f80ce2aSJacob Faibussowitsch /* CHKERRQ(PetscObjectSetName((PetscObject) z, "Reconstructed vector")); */ 77c4762a1bSJed Brown 78*b122ec5aSJacob Faibussowitsch CHKERRQ(PetscFinalize()); 79*b122ec5aSJacob Faibussowitsch return 0; 80c4762a1bSJed Brown 81c4762a1bSJed Brown } 82