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> 4*ad0e0ea3SStefano Zampini int main(int argc,char **args) 5c4762a1bSJed Brown { 6c4762a1bSJed Brown PetscErrorCode ierr; 7c4762a1bSJed Brown PetscMPIInt rank,size; 8c4762a1bSJed Brown PetscInt N0=10,N1=10,N2=10,N3=10,N4=10,N=N0*N1*N2*N3*N4; 9c4762a1bSJed Brown PetscRandom rdm; 10c4762a1bSJed Brown PetscReal enorm; 11c4762a1bSJed Brown Vec x,y,z,input,output; 12c4762a1bSJed Brown Mat A; 13c4762a1bSJed Brown PetscInt DIM, dim[5],vsize; 14c4762a1bSJed Brown PetscReal fac; 15c4762a1bSJed Brown 16c4762a1bSJed Brown ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 17c4762a1bSJed Brown #if defined(PETSC_USE_COMPLEX) 18c4762a1bSJed Brown SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP, "This example requires real numbers"); 19c4762a1bSJed Brown #endif 20c4762a1bSJed Brown ierr = MPI_Comm_size(PETSC_COMM_WORLD, &size);CHKERRQ(ierr); 21c4762a1bSJed Brown ierr = MPI_Comm_rank(PETSC_COMM_WORLD, &rank);CHKERRQ(ierr); 22c4762a1bSJed Brown 23c4762a1bSJed Brown if (size!=1) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP, "This is a uni-processor example only"); 24c4762a1bSJed Brown ierr = PetscRandomCreate(PETSC_COMM_SELF, &rdm);CHKERRQ(ierr); 25c4762a1bSJed Brown ierr = PetscRandomSetFromOptions(rdm);CHKERRQ(ierr); 26c4762a1bSJed Brown ierr = VecCreate(PETSC_COMM_SELF,&input);CHKERRQ(ierr); 27c4762a1bSJed Brown ierr = VecSetSizes(input,N,N);CHKERRQ(ierr); 28c4762a1bSJed Brown ierr = VecSetFromOptions(input);CHKERRQ(ierr); 29c4762a1bSJed Brown ierr = VecSetRandom(input,rdm);CHKERRQ(ierr); 30c4762a1bSJed Brown ierr = VecDuplicate(input,&output); 31c4762a1bSJed Brown 32c4762a1bSJed Brown DIM = 5; dim[0] = N0; dim[1] = N1; dim[2] = N2; dim[3] = N3; dim[4] = N4; 33c4762a1bSJed Brown ierr = MatCreateFFT(PETSC_COMM_SELF,DIM,dim,MATFFTW,&A);CHKERRQ(ierr); 34c4762a1bSJed Brown ierr = MatCreateVecs(A,&x,&y);CHKERRQ(ierr); 35c4762a1bSJed Brown ierr = MatCreateVecs(A,&z,NULL);CHKERRQ(ierr); 36c4762a1bSJed Brown 37c4762a1bSJed Brown ierr = VecGetSize(x,&vsize);CHKERRQ(ierr); 38c4762a1bSJed Brown printf("The vector size of input from the main routine is %d\n",vsize); 39c4762a1bSJed Brown 40c4762a1bSJed Brown ierr = VecGetSize(z,&vsize);CHKERRQ(ierr); 41c4762a1bSJed Brown printf("The vector size of output from the main routine is %d\n",vsize); 42c4762a1bSJed Brown 43c4762a1bSJed Brown ierr = InputTransformFFT(A,input,x);CHKERRQ(ierr); 44c4762a1bSJed Brown 45c4762a1bSJed Brown ierr = MatMult(A,x,y);CHKERRQ(ierr); 46c4762a1bSJed Brown ierr = MatMultTranspose(A,y,z);CHKERRQ(ierr); 47c4762a1bSJed Brown 48c4762a1bSJed Brown ierr = OutputTransformFFT(A,z,output);CHKERRQ(ierr); 49c4762a1bSJed Brown fac = 1.0/(PetscReal)N; 50c4762a1bSJed Brown ierr = VecScale(output,fac);CHKERRQ(ierr); 51c4762a1bSJed Brown /* 52c4762a1bSJed Brown ierr = VecAssemblyBegin(input);CHKERRQ(ierr); 53c4762a1bSJed Brown ierr = VecAssemblyEnd(input);CHKERRQ(ierr); 54c4762a1bSJed Brown ierr = VecAssemblyBegin(output);CHKERRQ(ierr); 55c4762a1bSJed Brown ierr = VecAssemblyEnd(output);CHKERRQ(ierr); 56c4762a1bSJed Brown 57c4762a1bSJed Brown ierr = VecView(input,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 58c4762a1bSJed Brown ierr = VecView(output,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 59c4762a1bSJed Brown */ 60c4762a1bSJed Brown ierr = VecAXPY(output,-1.0,input);CHKERRQ(ierr); 61c4762a1bSJed Brown ierr = VecNorm(output,NORM_1,&enorm);CHKERRQ(ierr); 62c4762a1bSJed Brown /* if (enorm > 1.e-14) { */ 63c4762a1bSJed Brown ierr = PetscPrintf(PETSC_COMM_SELF," Error norm of |x - z| %e\n",enorm);CHKERRQ(ierr); 64c4762a1bSJed Brown /* } */ 65c4762a1bSJed Brown 66c4762a1bSJed Brown ierr = VecDestroy(&output);CHKERRQ(ierr); 67c4762a1bSJed Brown ierr = VecDestroy(&input);CHKERRQ(ierr); 68c4762a1bSJed Brown ierr = VecDestroy(&x);CHKERRQ(ierr); 69c4762a1bSJed Brown ierr = VecDestroy(&y);CHKERRQ(ierr); 70c4762a1bSJed Brown ierr = VecDestroy(&z);CHKERRQ(ierr); 71c4762a1bSJed Brown ierr = MatDestroy(&A);CHKERRQ(ierr); 72c4762a1bSJed Brown ierr = PetscRandomDestroy(&rdm);CHKERRQ(ierr); 73c4762a1bSJed Brown ierr = PetscFinalize(); 74c4762a1bSJed Brown return ierr; 75c4762a1bSJed Brown 76c4762a1bSJed Brown } 77