1c4762a1bSJed Brown static char help[]="This program illustrates the use of PETSc-fftw interface for sequential real DFT\n"; 2c4762a1bSJed Brown #include <petscmat.h> 3c4762a1bSJed Brown #include <fftw3-mpi.h> 4ad0e0ea3SStefano Zampini int main(int argc,char **args) 5c4762a1bSJed Brown { 6c4762a1bSJed Brown PetscMPIInt rank,size; 7c4762a1bSJed Brown PetscInt N0=10,N1=10,N2=10,N3=10,N4=10,N=N0*N1*N2*N3*N4; 8c4762a1bSJed Brown PetscRandom rdm; 9c4762a1bSJed Brown PetscReal enorm; 10c4762a1bSJed Brown Vec x,y,z,input,output; 11c4762a1bSJed Brown Mat A; 12c4762a1bSJed Brown PetscInt DIM, dim[5],vsize; 13c4762a1bSJed Brown PetscReal fac; 14c4762a1bSJed Brown 15*b122ec5aSJacob Faibussowitsch CHKERRQ(PetscInitialize(&argc,&args,(char*)0,help)); 16c4762a1bSJed Brown #if defined(PETSC_USE_COMPLEX) 17c4762a1bSJed Brown SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP, "This example requires real numbers"); 18c4762a1bSJed Brown #endif 195f80ce2aSJacob Faibussowitsch CHKERRMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size)); 205f80ce2aSJacob Faibussowitsch CHKERRMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank)); 21c4762a1bSJed Brown 222c71b3e2SJacob Faibussowitsch PetscCheckFalse(size!=1,PETSC_COMM_WORLD,PETSC_ERR_SUP, "This is a uni-processor example only"); 235f80ce2aSJacob Faibussowitsch CHKERRQ(PetscRandomCreate(PETSC_COMM_SELF, &rdm)); 245f80ce2aSJacob Faibussowitsch CHKERRQ(PetscRandomSetFromOptions(rdm)); 255f80ce2aSJacob Faibussowitsch CHKERRQ(VecCreate(PETSC_COMM_SELF,&input)); 265f80ce2aSJacob Faibussowitsch CHKERRQ(VecSetSizes(input,N,N)); 275f80ce2aSJacob Faibussowitsch CHKERRQ(VecSetFromOptions(input)); 285f80ce2aSJacob Faibussowitsch CHKERRQ(VecSetRandom(input,rdm)); 295f80ce2aSJacob Faibussowitsch CHKERRQ(VecDuplicate(input,&output)); 30c4762a1bSJed Brown 31c4762a1bSJed Brown DIM = 5; dim[0] = N0; dim[1] = N1; dim[2] = N2; dim[3] = N3; dim[4] = N4; 325f80ce2aSJacob Faibussowitsch CHKERRQ(MatCreateFFT(PETSC_COMM_SELF,DIM,dim,MATFFTW,&A)); 335f80ce2aSJacob Faibussowitsch CHKERRQ(MatCreateVecs(A,&x,&y)); 345f80ce2aSJacob Faibussowitsch CHKERRQ(MatCreateVecs(A,&z,NULL)); 35c4762a1bSJed Brown 365f80ce2aSJacob Faibussowitsch CHKERRQ(VecGetSize(x,&vsize)); 37c4762a1bSJed Brown printf("The vector size of input from the main routine is %d\n",vsize); 38c4762a1bSJed Brown 395f80ce2aSJacob Faibussowitsch CHKERRQ(VecGetSize(z,&vsize)); 40c4762a1bSJed Brown printf("The vector size of output from the main routine is %d\n",vsize); 41c4762a1bSJed Brown 425f80ce2aSJacob Faibussowitsch CHKERRQ(InputTransformFFT(A,input,x)); 43c4762a1bSJed Brown 445f80ce2aSJacob Faibussowitsch CHKERRQ(MatMult(A,x,y)); 455f80ce2aSJacob Faibussowitsch CHKERRQ(MatMultTranspose(A,y,z)); 46c4762a1bSJed Brown 475f80ce2aSJacob Faibussowitsch CHKERRQ(OutputTransformFFT(A,z,output)); 48c4762a1bSJed Brown fac = 1.0/(PetscReal)N; 495f80ce2aSJacob Faibussowitsch CHKERRQ(VecScale(output,fac)); 50c4762a1bSJed Brown /* 515f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyBegin(input)); 525f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyEnd(input)); 535f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyBegin(output)); 545f80ce2aSJacob Faibussowitsch CHKERRQ(VecAssemblyEnd(output)); 55c4762a1bSJed Brown 565f80ce2aSJacob Faibussowitsch CHKERRQ(VecView(input,PETSC_VIEWER_STDOUT_WORLD)); 575f80ce2aSJacob Faibussowitsch CHKERRQ(VecView(output,PETSC_VIEWER_STDOUT_WORLD)); 58c4762a1bSJed Brown */ 595f80ce2aSJacob Faibussowitsch CHKERRQ(VecAXPY(output,-1.0,input)); 605f80ce2aSJacob Faibussowitsch CHKERRQ(VecNorm(output,NORM_1,&enorm)); 61c4762a1bSJed Brown /* if (enorm > 1.e-14) { */ 625f80ce2aSJacob Faibussowitsch CHKERRQ(PetscPrintf(PETSC_COMM_SELF," Error norm of |x - z| %e\n",enorm)); 63c4762a1bSJed Brown /* } */ 64c4762a1bSJed Brown 655f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&output)); 665f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&input)); 675f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&x)); 685f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&y)); 695f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&z)); 705f80ce2aSJacob Faibussowitsch CHKERRQ(MatDestroy(&A)); 715f80ce2aSJacob Faibussowitsch CHKERRQ(PetscRandomDestroy(&rdm)); 72*b122ec5aSJacob Faibussowitsch CHKERRQ(PetscFinalize()); 73*b122ec5aSJacob Faibussowitsch return 0; 74c4762a1bSJed Brown 75c4762a1bSJed Brown } 76