1*c4762a1bSJed Brown static char help[]="This program illustrates the use of PETSc-fftw interface for parallel real DFT\n"; 2*c4762a1bSJed Brown #include <petscmat.h> 3*c4762a1bSJed Brown #include <fftw3-mpi.h> 4*c4762a1bSJed Brown /*extern PetscErrorCode MatCreateVecsFFT(Mat,Vec *,Vec *,Vec *);*/ 5*c4762a1bSJed Brown PetscInt main(PetscInt argc,char **args) 6*c4762a1bSJed Brown { 7*c4762a1bSJed Brown PetscErrorCode ierr; 8*c4762a1bSJed Brown PetscMPIInt rank,size; 9*c4762a1bSJed Brown PetscInt N0=4096,N1=4096,N2=256,N3=10,N4=10,N=N0*N1; 10*c4762a1bSJed Brown PetscRandom rdm; 11*c4762a1bSJed Brown PetscReal enorm; 12*c4762a1bSJed Brown Vec x,y,z,input,output; 13*c4762a1bSJed Brown Mat A; 14*c4762a1bSJed Brown PetscInt DIM, dim[5],vsize,row,col; 15*c4762a1bSJed Brown PetscReal fac; 16*c4762a1bSJed Brown 17*c4762a1bSJed Brown ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 18*c4762a1bSJed Brown ierr = MPI_Comm_size(PETSC_COMM_WORLD, &size);CHKERRQ(ierr); 19*c4762a1bSJed Brown ierr = MPI_Comm_rank(PETSC_COMM_WORLD, &rank);CHKERRQ(ierr); 20*c4762a1bSJed Brown 21*c4762a1bSJed Brown #if defined(PETSC_USE_COMPLEX) 22*c4762a1bSJed Brown SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP, "Example for Real DFT. Your current data type is complex!"); 23*c4762a1bSJed Brown #endif 24*c4762a1bSJed Brown ierr = PetscRandomCreate(PETSC_COMM_WORLD, &rdm);CHKERRQ(ierr); 25*c4762a1bSJed Brown ierr = PetscRandomSetFromOptions(rdm);CHKERRQ(ierr); 26*c4762a1bSJed Brown ierr = VecCreate(PETSC_COMM_WORLD,&input);CHKERRQ(ierr); 27*c4762a1bSJed Brown ierr = VecSetSizes(input,PETSC_DECIDE,N);CHKERRQ(ierr); 28*c4762a1bSJed Brown ierr = VecSetFromOptions(input);CHKERRQ(ierr); 29*c4762a1bSJed Brown ierr = VecSetRandom(input,rdm);CHKERRQ(ierr); 30*c4762a1bSJed Brown ierr = VecDuplicate(input,&output); 31*c4762a1bSJed Brown 32*c4762a1bSJed Brown DIM = 2; dim[0] = N0; dim[1] = N1; dim[2] = N2; dim[3] = N3; dim[4] = N4; 33*c4762a1bSJed Brown ierr = MatCreateFFT(PETSC_COMM_WORLD,DIM,dim,MATFFTW,&A);CHKERRQ(ierr); 34*c4762a1bSJed Brown ierr = MatGetLocalSize(A,&row,&col);CHKERRQ(ierr); 35*c4762a1bSJed Brown printf("The Matrix size is %d and %d from process %d\n",row,col,rank); 36*c4762a1bSJed Brown ierr = MatCreateVecsFFTW(A,&x,&y,&z);CHKERRQ(ierr); 37*c4762a1bSJed Brown 38*c4762a1bSJed Brown ierr = VecGetSize(x,&vsize);CHKERRQ(ierr); 39*c4762a1bSJed Brown 40*c4762a1bSJed Brown ierr = VecGetSize(z,&vsize);CHKERRQ(ierr); 41*c4762a1bSJed Brown printf("The vector size of output from the main routine is %d\n",vsize); 42*c4762a1bSJed Brown 43*c4762a1bSJed Brown ierr = VecScatterPetscToFFTW(A,input,x);CHKERRQ(ierr); 44*c4762a1bSJed Brown /*ierr = VecDestroy(&input);CHKERRQ(ierr);*/ 45*c4762a1bSJed Brown ierr = MatMult(A,x,y);CHKERRQ(ierr); 46*c4762a1bSJed Brown ierr = MatMultTranspose(A,y,z);CHKERRQ(ierr); 47*c4762a1bSJed Brown ierr = VecScatterFFTWToPetsc(A,z,output);CHKERRQ(ierr); 48*c4762a1bSJed Brown /*ierr = VecDestroy(&z);CHKERRQ(ierr);*/ 49*c4762a1bSJed Brown fac = 1.0/(PetscReal)N; 50*c4762a1bSJed Brown ierr = VecScale(output,fac);CHKERRQ(ierr); 51*c4762a1bSJed Brown 52*c4762a1bSJed Brown ierr = VecAssemblyBegin(input);CHKERRQ(ierr); 53*c4762a1bSJed Brown ierr = VecAssemblyEnd(input);CHKERRQ(ierr); 54*c4762a1bSJed Brown ierr = VecAssemblyBegin(output);CHKERRQ(ierr); 55*c4762a1bSJed Brown ierr = VecAssemblyEnd(output);CHKERRQ(ierr); 56*c4762a1bSJed Brown 57*c4762a1bSJed Brown /* ierr = VecView(input,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);*/ 58*c4762a1bSJed Brown /* ierr = VecView(output,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);*/ 59*c4762a1bSJed Brown 60*c4762a1bSJed Brown ierr = VecAXPY(output,-1.0,input);CHKERRQ(ierr); 61*c4762a1bSJed Brown ierr = VecNorm(output,NORM_1,&enorm);CHKERRQ(ierr); 62*c4762a1bSJed Brown if (enorm > 1.e-14) { 63*c4762a1bSJed Brown ierr = PetscPrintf(PETSC_COMM_SELF," Error norm of |x - z| %e\n",enorm);CHKERRQ(ierr); 64*c4762a1bSJed Brown } 65*c4762a1bSJed Brown 66*c4762a1bSJed Brown ierr = VecDestroy(&x);CHKERRQ(ierr); 67*c4762a1bSJed Brown ierr = VecDestroy(&y);CHKERRQ(ierr); 68*c4762a1bSJed Brown ierr = VecDestroy(&z);CHKERRQ(ierr); 69*c4762a1bSJed Brown ierr = VecDestroy(&output);CHKERRQ(ierr); 70*c4762a1bSJed Brown ierr = VecDestroy(&input);CHKERRQ(ierr); 71*c4762a1bSJed Brown ierr = MatDestroy(&A);CHKERRQ(ierr); 72*c4762a1bSJed Brown ierr = PetscRandomDestroy(&rdm);CHKERRQ(ierr); 73*c4762a1bSJed Brown ierr = PetscFinalize(); 74*c4762a1bSJed Brown return ierr; 75*c4762a1bSJed Brown 76*c4762a1bSJed Brown } 77