static void pnfft_perform_guru(
const ptrdiff_t *N, const ptrdiff_t *n, ptrdiff_t local_M,
int m, const double *x_max, unsigned window_flag,
const int *np, MPI_Comm comm,
pnfft_complex **f, double *f_hat_sum
)
{
ptrdiff_t local_N[3], local_N_start[3];
double lower_border[3], upper_border[3];
double local_sum = 0, time, time_max;
MPI_Comm comm_cart_3d;
pnfft_complex *f_hat;
double *x;
pnfft_plan pnfft;
/* create three-dimensional process grid of size np[0] x np[1] x np[2], if possible */
if( pnfft_create_procmesh(3, comm, np, &comm_cart_3d) ){
pfft_fprintf(comm, stderr, "Error: Procmesh of size %d x %d x %d does not fit to number of allocated processes.\n", np[0], np[1], np[2]);
pfft_fprintf(comm, stderr, " Please allocate %d processes (mpiexec -np %d ...) or change the procmesh (with -pnfft_np * * *).\n", np[0]*np[1]*np[2], np[0]*np[1]*np[2]);
MPI_Finalize();
exit(1);
}
/* get parameters of data distribution */
pnfft_local_size_guru(3, N, n, x_max, m, comm_cart_3d, PNFFT_TRANSPOSED_NONE,
local_N, local_N_start, lower_border, upper_border);
/* plan parallel NFFT */
pnfft = pnfft_init_guru(3, N, n, x_max, local_M, m,
PNFFT_MALLOC_X| PNFFT_MALLOC_F_HAT| PNFFT_MALLOC_F| window_flag, PFFT_ESTIMATE,
comm_cart_3d);
/* get data pointers */
f_hat = pnfft_get_f_hat(pnfft);
*f = pnfft_get_f(pnfft);
x = pnfft_get_x(pnfft);
/* initialize Fourier coefficients */
pnfft_init_f_hat_3d(N, local_N, local_N_start, PNFFT_TRANSPOSED_NONE,
f_hat);
/* initialize nonequispaced nodes */
srand(0);
init_random_x(lower_border, upper_border, x_max, local_M,
x);
/* execute parallel NFFT */
time = -MPI_Wtime();
pnfft_trafo(pnfft);
time += MPI_Wtime();
/* print timing */
MPI_Reduce(&time, &time_max, 1, MPI_DOUBLE, MPI_MAX, 0, comm);
pfft_printf(comm, "pnfft_trafo needs %6.2e s\n", time_max);
/* calculate norm of Fourier coefficients for calculation of relative error */
for(ptrdiff_t k=0; k<local_N[0]*local_N[1]*local_N[2]; k++)
local_sum += cabs(f_hat[k]);
MPI_Allreduce(&local_sum, f_hat_sum, 1, MPI_DOUBLE, MPI_SUM, comm_cart_3d);
/* free mem and finalize, do not free nfft.f */
pnfft_finalize(pnfft, PNFFT_FREE_X | PNFFT_FREE_F_HAT);
MPI_Comm_free(&comm_cart_3d);
}
int main(int argc, char **argv){
int np[3];
ptrdiff_t N[3], local_M;
ptrdiff_t local_N[3], local_N_start[3];
double lower_border[3], upper_border[3];
MPI_Comm comm_cart_3d;
pnfft_complex *f_hat, *f;
double *x;
pnfft_plan pnfft;
MPI_Init(&argc, &argv);
pnfft_init();
/* Set default values */
N[0] = N[1] = N[2] = 16;
np[0]=2; np[1]=2; np[2]=2;
local_M = N[0]*N[1]*N[2]/(np[0]*np[1]*np[2]);
/* Print infos */
pfft_printf(MPI_COMM_WORLD, "******************************************************************************************************\n");
pfft_printf(MPI_COMM_WORLD, "* Computation of parallel NFFT\n");
pfft_printf(MPI_COMM_WORLD, "* for N[0] x N[1] x N[2] = %td x %td x %td Fourier coefficients\n", N[0], N[1], N[2]);
pfft_printf(MPI_COMM_WORLD, "* at local_M = %td nodes per process\n", local_M);
pfft_printf(MPI_COMM_WORLD, "* on np[0] x np[1] x np[2] = %td x %td x %td processes\n", np[0], np[1], np[2]);
pfft_printf(MPI_COMM_WORLD, "*******************************************************************************************************\n\n");
/* create three-dimensional process grid of size np[0] x np[1] x np[2], if possible */
if( pnfft_create_procmesh(3, MPI_COMM_WORLD, np, &comm_cart_3d) ){
pfft_fprintf(MPI_COMM_WORLD, stderr, "Error: Procmesh of size %d x %d x %d does not fit to number of allocated processes.\n", np[0], np[1], np[2]);
pfft_fprintf(MPI_COMM_WORLD, stderr, " Please allocate %d processes (mpiexec -np %d ...) or change the procmesh (with -pnfft_np * * *).\n", np[0]*np[1]*np[2], np[0]*np[1]*np[2]);
MPI_Finalize();
return 1;
}
/* Get parameters of data distribution */
pnfft_local_size_3d(N, comm_cart_3d, PNFFT_TRANSPOSED_NONE,
local_N, local_N_start, lower_border, upper_border);
/* Plan parallel NFFT */
pnfft = pnfft_init_3d(N, local_M, comm_cart_3d);
/* Get data pointers */
f_hat = pnfft_get_f_hat(pnfft);
f = pnfft_get_f(pnfft);
x = pnfft_get_x(pnfft);
/* Initialize Fourier coefficients */
pnfft_init_f_hat_3d(N, local_N, local_N_start, PNFFT_TRANSPOSED_NONE,
f_hat);
/* Initialize nonequispaced nodes */
init_random_x(lower_border, upper_border, local_M,
x);
/* Print input Fourier coefficents */
vpr_complex(comm_cart_3d, 8, f_hat,
"Input Fourier coefficients on process 1:");
/* Execute parallel NFFT */
pnfft_trafo(pnfft);
/* Print NFFT results */
vpr_complex(comm_cart_3d, 8, f,
"PNFFT Results on process 1:");
/* Execute parallel adjoint NFFT */
pnfft_adj(pnfft);
/* Scale data */
for(ptrdiff_t l=0; l < local_N[0] * local_N[1] * local_N[2]; l++)
f_hat[l] /= (N[0]*N[1]*N[2]);
/* Print output Fourier coefficents */
vpr_complex(comm_cart_3d, 8, f_hat,
"Fourier coefficients after one forward and backward PNFFT on process 1:");
/* free mem and finalize */
pnfft_finalize(pnfft, PNFFT_FREE_X | PNFFT_FREE_F_HAT| PNFFT_FREE_F);
MPI_Comm_free(&comm_cart_3d);
pnfft_cleanup();
MPI_Finalize();
return 0;
}
int main(int argc, char **argv)
{
int np[3];
ptrdiff_t N[3];
ptrdiff_t local_M;
double err;
MPI_Comm comm_cart_3d;
ptrdiff_t local_N_c2c[3], local_N_start_c2c[3];
double lower_border_c2c[3], upper_border_c2c[3];
pnfft_plan plan_c2c;
pnfft_complex *f_hat_c2c, *f_c2c;
double *x_c2c;
ptrdiff_t local_N_c2r[3], local_N_start_c2r[3];
double lower_border_c2r[3], upper_border_c2r[3];
pnfft_plan plan_c2r;
pnfft_complex *f_hat_c2r;
double *x_c2r, *f_c2r;
/* Initialize MPI and PFFT */
MPI_Init(&argc, &argv);
pnfft_init();
np[0] = 2; np[1] = 2; np[2] = 4;
// for bigger transforms the data gets distributed differently, which makes comparing the results harder.
N[0] = 8; N[1] = 8; N[2] = 16;
local_M = N[0]*N[1]*N[2]/(np[0]*np[1]*np[2]);
/* Print infos */
pfft_printf(MPI_COMM_WORLD, "******************************************************************************************************\n");
pfft_printf(MPI_COMM_WORLD, "* Computation of parallel NFFT\n");
pfft_printf(MPI_COMM_WORLD, "* for N[0] x N[1] x N[2] = %td x %td x %td Fourier coefficients)\n", N[0], N[1], N[2]);
pfft_printf(MPI_COMM_WORLD, "* at local_M = %td nodes per process\n", local_M);
pfft_printf(MPI_COMM_WORLD, "* on np[0] x np[1] x np[2] = %td x %td x %td processes\n", np[0], np[1], np[2]);
pfft_printf(MPI_COMM_WORLD, "*******************************************************************************************************\n\n");
/* create three-dimensional process grid of size np[0] x np[1] x np[2], if possible */
if( pnfft_create_procmesh(3, MPI_COMM_WORLD, np, &comm_cart_3d) ){
pfft_fprintf(MPI_COMM_WORLD, stderr, "Error: Procmesh of size %d x %d x %d does not fit to number of allocated processes.\n", np[0], np[1], np[2]);
pfft_fprintf(MPI_COMM_WORLD, stderr, " Please allocate %d processes (mpiexec -np %d ...) or change the procmesh (with -pnfft_np * * *).\n", np[0]*np[1]*np[2], np[0]*np[1]*np[2]);
MPI_Finalize();
return 1;
}
/* Get parameters of data distribution */
pnfft_local_size_3d(N, comm_cart_3d, PNFFT_TRANSPOSED_NONE,
local_N_c2c, local_N_start_c2c, lower_border_c2c, upper_border_c2c);
pnfft_local_size_3d_c2r(N, comm_cart_3d, PNFFT_TRANSPOSED_NONE,
local_N_c2r, local_N_start_c2r, lower_border_c2r, upper_border_c2r);
/* Plan parallel NFFT */
plan_c2c = pnfft_init_adv(3, N, local_M,
PNFFT_TRANSPOSED_NONE| PNFFT_WINDOW_SINC_POWER| PNFFT_MALLOC_X| PNFFT_MALLOC_F_HAT| PNFFT_MALLOC_F, PFFT_ESTIMATE,
comm_cart_3d);
plan_c2r = pnfft_init_adv_c2r(3, N, local_M,
PNFFT_TRANSPOSED_NONE| PNFFT_WINDOW_SINC_POWER| PNFFT_MALLOC_X| PNFFT_MALLOC_F_HAT| PNFFT_MALLOC_F, PFFT_ESTIMATE,
comm_cart_3d);
f_hat_c2c = pnfft_get_f_hat(plan_c2c);
f_c2c = pnfft_get_f(plan_c2c);
x_c2c = pnfft_get_x(plan_c2c);
f_hat_c2r = pnfft_get_f_hat(plan_c2r);
f_c2r = pnfft_get_f(plan_c2r);
x_c2r = pnfft_get_x(plan_c2r);
/* Initialize Fourier coefficients with random numbers */
init_input(N, local_N_c2c, local_N_start_c2c, f_hat_c2c);
init_input(N, local_N_c2r, local_N_start_c2r, f_hat_c2r);
/* Initialize nodes with random numbers */
// pnfft_init_x_3d(lower_border_c2c, upper_border_c2c, local_M, x_c2c);
init_equispaced_x(N, lower_border_c2c, upper_border_c2c, x_c2c);
for (int k=0; k<local_M*3; k++)
x_c2r[k] = x_c2c[k];
/* execute parallel NFFT */
pnfft_trafo(plan_c2c);
MPI_Barrier(MPI_COMM_WORLD);
pnfft_trafo(plan_c2r);
MPI_Barrier(MPI_COMM_WORLD);
err = compare_complex_real(local_M, f_c2c, f_c2r, comm_cart_3d);
pfft_printf(MPI_COMM_WORLD, "max error between c2c and c2r after trafo: %6.2e\n", err);
/* free mem and finalize */
pnfft_finalize(plan_c2c, PNFFT_FREE_X | PNFFT_FREE_F_HAT | PNFFT_FREE_F);
pnfft_finalize(plan_c2r, PNFFT_FREE_X | PNFFT_FREE_F_HAT | PNFFT_FREE_F);
MPI_Comm_free(&comm_cart_3d);
/* Finalize MPI */
MPI_Finalize();
return 0;
}