21   int          n = 10, N, Ny, ndim = 4, i, dim[4], DIM;  in main()  local
46   for (DIM = 0; DIM < ndim; DIM++) dim[DIM] = n; /* size of real space vector in DIM-dimension */  in main()
50   for (DIM = 1; DIM < 5; DIM++) {  in main()
54     for (i = 0; i < DIM - 1; i++) N *= dim[i];  in main()
56     Ny *= 2 * (dim[DIM - 1] / 2 + 1); /* add padding elements to output vector y */  in main()
57     N *= dim[DIM - 1];  in main()
59     PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n %d-D: FFTW on vector of size %d \n", DIM, N));  in main()
78     PetscCall(PetscPrintf(PETSC_COMM_SELF, "DIM: %d, N %d, Ny %d\n", DIM, N, Ny));  in main()
80     switch (DIM) {  in main()
94       fplan = fftw_plan_dft_r2c(DIM, (int *)dim, (double *)x_array, (fftw_complex *)y_array, flags);  in main()
95       bplan = fftw_plan_dft_c2r(DIM, (int *)dim, (fftw_complex *)y_array, (double *)z_array, flags);  in main()