void c_fft2d_serial(complex inp[N][N])
{
int i, j;
for (i = 0; i < N; i++)
{
c_fft1d(&inp[i][0], N, -1);
}
transpose(inp);
for (i = 0; i < N; i++)
{
c_fft1d(&inp[i][0], N, -1);
}
transpose(inp);
}
void execute_fft(complex data[512*512], int type, int p, int my_rank) {
int i, j, workload;
workload = 512 / p;
for(i = 0; i < workload; i++) {
c_fft1d(&data[(my_rank * workload * 512) + (512 * i)], 512, type);
}
}
void c_rowwise_inv_fft2d(complex *local_mat, int local_n)
{
int i;
for (i = 0; i < local_n; i++)
{
c_fft1d((local_mat+N*i), N, 1);
}
}
void convolution(int my_id, int p){
int i, j, k;
int chunkSize;
double start, end;
double time[14];
/* Input data */
float input_1[N][N], input_2[N][N];
/* Output data */
float output[N][N];
/* Set the chunk size for each processor */
chunkSize = N/p;
/* Two arrays storing the local data distributed by rank 0 */
float local_data1[N][N], local_data2[N][N];
/* Local matrix for matrix multiplication */
float local_data3[chunkSize][N];
/* A complex array storing the temp row to operate FFT */
complex temp_data[N];
/* Initialization of the original Matrix and distribution of data */
if(my_id == 0){
printf("2D convolution using SPMD model and MPI Collective operations\n");
start = MPI_Wtime();
/*Read data from the files*/
readFile(input_1, input_2);
time[0] = MPI_Wtime();
printf("Reading file takes %f s.\n", time[0] - start);
}
/* Scatter all the data to local data */
MPI_Scatter(input_1, chunkSize*N, MPI_FLOAT,
local_data1, chunkSize*N, MPI_FLOAT,
0, MPI_COMM_WORLD);
MPI_Scatter(input_2, chunkSize*N, MPI_FLOAT,
local_data2, chunkSize*N, MPI_FLOAT,
0, MPI_COMM_WORLD);
MPI_Barrier(MPI_COMM_WORLD);
/* Compute time for distributing data */
if(my_id == 0){
time[1] = MPI_Wtime();
printf("Scattering data of rows to each processor takes %f s.\n", time[1] - time[0]);
}
/* Row FFT */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each row for im1 */
temp_data[j].r = local_data1[i][j];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data1[i][j] = temp_data[j].r;
for(j = 0; j < N; j++){
/* FFT each row for im2 */
temp_data[j].r = local_data2[i][j];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data2[i][j] = temp_data[j].r;
}
/* Gather all the data and distribute in columns */
if(my_id == 0){
time[2] = MPI_Wtime();
printf("FFT each row for input im1 and im2 takes %f s.\n", time[2] - time[1]);
}
MPI_Gather(local_data1, chunkSize*N, MPI_FLOAT,
input_1, chunkSize*N, MPI_FLOAT,
0, MPI_COMM_WORLD);
MPI_Gather(local_data2, chunkSize*N, MPI_FLOAT,
input_2, chunkSize*N, MPI_FLOAT,
0, MPI_COMM_WORLD);
if(my_id == 0){
time[3] = MPI_Wtime();
printf("Gathering all the data from different rows takes %f s.\n", time[3] - time[2]);
}
/* Initialize a new vector for distributing columns */
MPI_Datatype column, col;
/* Column vector */
MPI_Type_vector(N, 1, N, MPI_FLOAT, &col);
MPI_Type_commit(&col);
MPI_Type_create_resized(col, 0, 1*sizeof(float), &column);
MPI_Type_commit(&column);
/* Scatter all the data to column local data */
MPI_Scatter(input_1, chunkSize, column,
local_data1, chunkSize, column,
0, MPI_COMM_WORLD);
MPI_Scatter(input_2, chunkSize, column,
local_data2, chunkSize, column,
0, MPI_COMM_WORLD);
MPI_Barrier(MPI_COMM_WORLD);
if(my_id == 0){
time[4] = MPI_Wtime();
printf("Scattering data of columns to each processor takes %f s.\n", time[4] - time[3]);
}
/* Column FFT */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each column for im1 */
temp_data[j].r = local_data1[j][i];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data1[j][i] = temp_data[j].r;
for(j = 0; j < N; j++){
/* FFT each column for im2 */
temp_data[j].r = local_data2[j][i];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data2[j][i] = temp_data[j].r;
}
/* Gather all the columns from each rank */
if(my_id == 0){
time[5] = MPI_Wtime();
printf("FFT each column for input im1 and im2 takes %f s.\n", time[5] - time[4]);
}
MPI_Gather(local_data1, chunkSize, column,
input_1, chunkSize, column,
0, MPI_COMM_WORLD);
MPI_Gather(local_data2, chunkSize, column,
input_2, chunkSize, column,
0, MPI_COMM_WORLD);
MPI_Barrier(MPI_COMM_WORLD);
/* Compute time and distribute data to do matrix multiplication */
if(my_id == 0){
time[6] = MPI_Wtime();
printf("Gathering all the data from different columns takes %f s.\n", time[6] - time[5]);
}
MPI_Scatter(input_1, chunkSize*N, MPI_FLOAT,
local_data1, chunkSize*N, MPI_FLOAT,
0, MPI_COMM_WORLD);
/* Broadcast data2 to all the ranks */
MPI_Bcast(input_2, N*N, MPI_FLOAT, 0, MPI_COMM_WORLD);
MPI_Barrier(MPI_COMM_WORLD);
if(my_id == 0){
time[7] = MPI_Wtime();
printf("Scattering data for multiplication takes %f s.\n", time[7] - time[6]);
}
/* Matrix multiplication */
for(i = 0; i < chunkSize; i++)
for(j = 0; j < N; j++)
for(k = 0; k < N; k++)
local_data3[i][j] += local_data1[i][k]*input_2[k][j];
/* Collect multiplication results from each rank */
if(my_id == 0){
time[8] = MPI_Wtime();
printf("Matrix multiplication takes %f s.\n", time[8] - time[7]);
}
/* Inverse-2DFFT(row) for the output file */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each row for im1 */
temp_data[j].r = local_data3[i][j];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, 1);
for(j = 0; j < N; j++)
local_data3[i][j] = temp_data[j].r;
}
if(my_id == 0){
time[9] = MPI_Wtime();
printf("Inverse-2DFFT for out_1(row) takes %f s.\n", time[9] - time[8]);
}
MPI_Gather(local_data3, chunkSize*N, MPI_FLOAT,
output, chunkSize*N, MPI_FLOAT,
0, MPI_COMM_WORLD);
MPI_Barrier(MPI_COMM_WORLD);
if(my_id == 0){
time[10] = MPI_Wtime();
printf("Gathering all the data of Inverse-2DFFT for out_1(row) takes %f s.\n", time[10] - time[9]);
}
MPI_Scatter(output, chunkSize, column,
local_data1, chunkSize, column,
0, MPI_COMM_WORLD);
if(my_id == 0){
time[11] = MPI_Wtime();
printf("Scattering out_1(column) to each processor takes %f s.\n", time[11] - time[10]);
}
/* Inverse-2DFFT(column) for the output file */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each column for im1 */
temp_data[j].r = local_data1[j][i];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, 1);
for(j = 0; j < N; j++)
local_data1[j][i] = temp_data[j].r;
}
/* Gathering all the columns of the output file from each rank */
if(my_id == 0){
time[12] = MPI_Wtime();
printf("Inverse-2DFFT out_1(column) takes %f s.\n", time[12] - time[11]);
}
MPI_Gather(local_data1, chunkSize, column,
output, chunkSize, column,
0, MPI_COMM_WORLD);
if(my_id == 0){
time[13] = MPI_Wtime();
printf("Gathering all the data of the output file(column) takes %f s.\n", time[13] - time[12]);
writeFile(output);
end = MPI_Wtime();
printf("Writing the output file to file takes %f s.\n", end - time[13]);
printf("Total communication time of 2D convolution using MPI_Scatter&MPI_Gather takes %f s.\n", time[13] - time[12] + time[11] - time[10] + time[7] - time[5] + time[4] - time[2] + time[1] - time[0]);
printf("Total computing time of 2D convolution using MPI_Scatter&MPI_Gather takes %f s.\n", time[12] - time[11] + time[10] - time[7] + time[5] - time[4] + time[2] - time[1]);
printf("Total running time without loading/writing of 2D convolution using MPI_Scatter&MPI_Gather takes %f s.\n", time[13] - time[0]);
printf("Total running time of 2D convolution using MPI_Scatter&MPI_Gather takes %f s.\n", end - start);
}
/* Free vector column */
MPI_Type_free(&column);
MPI_Type_free(&col);
}
int main(int argc, char **argv)
{
int i, j, k;
double start, end;
/* Time array */
double time[9];
double comm_time = 0;
double comp_time = 0;
int chunkSize;
MPI_Status status;
/* Being used in FFT */
float data[N][N];
/* Being used in mm */
float input_1[N][N], input_2[N][N];
/* Local matrix for FFT */
float local_data[N][N];
/* World rank and processor, related to MPI_COMM_WORLD */
int world_id;
int world_processor;
/* Divided rank and processors for communication, related to taskcomm */
int task_id;
int task_processor;
/* A complex array storing the temp row to operate FFT */
complex temp_data[N];
/* Initialize rank and the number of processor for the MPI */
MPI_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &world_id);
MPI_Comm_size(MPI_COMM_WORLD, &world_processor);
/* Initialize a new vector for distributing columns */
MPI_Datatype column, col;
/* Column vector */
MPI_Type_vector(N, 1, N, MPI_FLOAT, &col);
MPI_Type_commit(&col);
MPI_Type_create_resized(col, 0, 1*sizeof(float), &column);
MPI_Type_commit(&column);
int task = world_id%4;
MPI_Comm taskcomm;
/* Split the MPI_COMM_WORLD */
MPI_Comm_split(MPI_COMM_WORLD, task, world_id, &taskcomm);
MPI_Comm_rank(taskcomm, &task_id);
MPI_Comm_size(taskcomm, &task_processor);
/* Initialize inter communicators */
MPI_Comm t1_t3_comm, t2_t3_comm, t3_t4_comm;
/* Calculate chunkSize */
chunkSize = N/task_processor;
/* Get the start time of all program */
if(world_id == 0){
printf("2D convolution using MPI task and data parallelism\n");
start = MPI_Wtime();
}
/* Each group completes work and send results by inter communicators */
if(task == 0){
// task 1
/* Create an inter communicator for task 1 and task 3 */
MPI_Intercomm_create(taskcomm, 0, MPI_COMM_WORLD, 2, 1, &t1_t3_comm);
if(task_id == 0){
time[0] = MPI_Wtime();
/* Read file */
readIm1File(data);
time[1] = MPI_Wtime();
printf("Group 1: Reading file 1_im1 takes %f s.\n", time[1] - time[0]);
}
/* Scatter data to local ranks */
MPI_Scatter(data, chunkSize*N, MPI_FLOAT,
local_data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
/* Compute time for distributing data */
if(task_id == 0){
time[2] = MPI_Wtime();
printf("Group 1: Scattering 1_im1(row) to each processor takes %f s.\n", time[2] - time[1]);
}
/* Do 1_im1 2d FFT */
/* Row FFT */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each row for im1 */
temp_data[j].r = local_data[i][j];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data[i][j] = temp_data[j].r;
}
/* Gather all the data and distribute in columns */
if(task_id == 0){
time[3] = MPI_Wtime();
printf("Group 1: FFT each row for 1_im1 takes %f s.\n", time[3] - time[2]);
}
/* Gather all the data of 1_im1 */
MPI_Gather(local_data, chunkSize*N, MPI_FLOAT,
data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
if(task_id == 0){
time[4] = MPI_Wtime();
printf("Group 1: Gathering all the data of 1_im1(row) takes %f s.\n", time[4] - time[3]);
}
/* Scatter all the data to column local data */
MPI_Scatter(data, chunkSize, column,
local_data, chunkSize, column,
0, taskcomm);
if(task_id == 0){
time[5] = MPI_Wtime();
printf("Group 1: Scattering 1_im1(column) to each processor takes %f s.\n", time[5] - time[4]);
}
/* Column FFT */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each column for im1 */
temp_data[j].r = local_data[j][i];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data[j][i] = temp_data[j].r;
}
/* Gather all the columns from each rank */
if(task_id == 0){
time[6] = MPI_Wtime();
printf("Group 1: FFT each column for 1_im1 takes %f s.\n", time[6] - time[5]);
}
MPI_Gather(local_data, chunkSize, column,
data, chunkSize, column,
0, taskcomm);
/* Compute time and distribute data to do matrix multiplication */
if(task_id == 0){
time[7] = MPI_Wtime();
printf("Group 1: Gathering all the data of 1_im1(column) takes %f s.\n", time[7] - time[6]);
/* Total time */
printf("Group 1: Total time for task 1 in group 1 takes %f s.\n", time[7] - time[0]);
comm_time += time[7] - time[6] + time[5] - time[3] + time[2] - time[1];
comp_time += time[6] - time[5] + time[3] - time[2];
/* Send data to group 3 via the inter communicator */
MPI_Send(data, N*N, MPI_FLOAT, task_id, 13, t1_t3_comm);
}
}
else if(task == 1){
// Task 2
/* Create an inter communicator for task 2 and task 3 */
MPI_Intercomm_create(taskcomm, 0, MPI_COMM_WORLD, 2, 2, &t2_t3_comm);
if(task_id == 0){
time[0] = MPI_Wtime();
/* Read file */
readIm2File(data);
time[1] = MPI_Wtime();
printf("Group 2: Reading file 1_im2 takes %f s.\n", time[1] - time[0]);
}
/* Scatter data to local ranks */
MPI_Scatter(data, chunkSize*N, MPI_FLOAT,
local_data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
/* Compute time for distributing data */
if(task_id == 0){
time[2] = MPI_Wtime();
printf("Group 2: Scatter 1_im2(row) to each processor takes %f s.\n", time[2] - time[1]);
}
/* Do 1_im1 2d FFT */
/* Row FFT */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each row for im1 */
temp_data[j].r = local_data[i][j];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data[i][j] = temp_data[j].r;
}
/* Gather all the data and distribute in columns */
if(task_id == 0){
time[3] = MPI_Wtime();
printf("Group 2: FFT each row for 1_im2 takes %f s.\n", time[3] - time[2]);
}
/* Gather all the data of 1_im1 */
MPI_Gather(local_data, chunkSize*N, MPI_FLOAT,
data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
if(task_id == 0){
time[4] = MPI_Wtime();
printf("Group 2: Gather all the data of 1_im2(row) takes %f s.\n", time[4] - time[3]);
}
/* Scatter all the data to column local data */
MPI_Scatter(data, chunkSize, column,
local_data, chunkSize, column,
0, taskcomm);
if(task_id == 0){
time[5] = MPI_Wtime();
printf("Group 2: Scatter 1_im2(column) to each processor takes %f s.\n", time[5] - time[4]);
}
/* Column FFT */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each column for im1 */
temp_data[j].r = local_data[j][i];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, -1);
for(j = 0; j < N; j++)
local_data[j][i] = temp_data[j].r;
}
/* Gather all the columns from each rank */
if(task_id == 0){
time[6] = MPI_Wtime();
printf("Group 2: FFT each column for 1_im2 takes %f s.\n", time[6] - time[5]);
}
MPI_Gather(local_data, chunkSize, column,
data, chunkSize, column,
0, taskcomm);
/* Compute time and distribute data to do matrix multiplication */
if(task_id == 0){
time[7] = MPI_Wtime();
printf("Group 2: Gather all the data of 1_im2(column) takes %f s.\n", time[7] - time[6]);
/* Total time */
printf("Group 2: Total time for task 2 in group 2 takes %f s.\n", time[7] - time[0]);
comm_time += time[7] - time[6] + time[5] - time[3] + time[2] - time[1];
comp_time += time[6] - time[5] + time[3] - time[2];
/* Send data to group 3 via the inter communicator */
MPI_Send(data, N*N, MPI_FLOAT, task_id, 23, t2_t3_comm);
}
}
else if(task == 2){
// Task 3
/* Local matrix for matrix multiplication */
float local_data2[chunkSize][N];
/* Create inter communicators for task 1 and task3, task 2 and task 3, task 3 and task 4 */
MPI_Intercomm_create(taskcomm, 0, MPI_COMM_WORLD, 0, 1, &t1_t3_comm);
MPI_Intercomm_create(taskcomm, 0, MPI_COMM_WORLD, 1, 2, &t2_t3_comm);
MPI_Intercomm_create(taskcomm, 0, MPI_COMM_WORLD, 3, 3, &t3_t4_comm);
/* Receive data from group 1 and group 2 */
if(task_id == 0){
time[0] = MPI_Wtime();
MPI_Recv(input_1, N*N, MPI_FLOAT, task_id, 13, t1_t3_comm, &status);
MPI_Recv(input_2, N*N, MPI_FLOAT, task_id, 23, t2_t3_comm, &status);
time[1] = MPI_Wtime();
/* Time of receiving data from group 1 and group 2 */
printf("Group 3: Receiving data from group 1 and group 2 takes %f s.\n", time[1] - time[0]);
}
/* Do matrix multiplication */
MPI_Scatter(input_1, chunkSize*N, MPI_FLOAT,
local_data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
/* Broadcast data2 to all the ranks */
MPI_Bcast(input_2, N*N, MPI_FLOAT, 0, taskcomm);
if(task_id == 0){
time[2] = MPI_Wtime();
printf("Group 3: Scattering data for multiplication takes %f s.\n", time[2] - time[1]);
}
/* Matrix multiplication */
for(i = 0; i < chunkSize; i++)
for(j = 0; j < N; j++){
local_data2[i][j] = 0;
for(k = 0; k < N; k++)
local_data2[i][j] += local_data[i][k]*input_2[k][j];
}
/* Collect multiplication result from each rank */
if(task_id == 0){
time[3] = MPI_Wtime();
printf("Group 3: Matrix multiplication takes %f s.\n", time[3] - time[2]);
}
/* Gather data */
MPI_Gather(local_data2, chunkSize*N, MPI_FLOAT,
data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
if(task_id == 0){
time[4] = MPI_Wtime();
printf("Group 3: Gathering data after Matrix multiplication takes %f s.\n", time[4] - time[3]);
/* total time */
printf("Group 3: Total time for task 3 in group 3 takes %f s.\n", time[4] - time[0]);
/* send result of matrix multiplication to group 4 */
MPI_Send(data, N*N, MPI_FLOAT, task_id, 34, t3_t4_comm);
}
comm_time += time[4] - time[3] + time[2] - time[0];
comp_time += time[3] - time[2];
MPI_Comm_free(&t1_t3_comm);
MPI_Comm_free(&t2_t3_comm);
}
else{
// Task 4
/* Create an inter communicator for task 3 and task 4 */
MPI_Intercomm_create(taskcomm, 0, MPI_COMM_WORLD, 2, 3, &t3_t4_comm);
/* Receive data from group 3 */
if(task_id == 0){
time[0] = MPI_Wtime();
MPI_Recv(data, N*N, MPI_FLOAT, task_id, 34, t3_t4_comm, &status);
time[1] = MPI_Wtime();
printf("Group 4: Receiving data from group 3 takes %f s.\n", time[1] - time[0]);
}
/* Scatter data to each processor */
MPI_Scatter(data, chunkSize*N, MPI_FLOAT,
local_data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
if(task_id == 0){
time[2] = MPI_Wtime();
printf("Group 4: Scattering data of rows to each processor takes %f s.\n", time[2] - time[1]);
}
/* Inverse-2DFFT(row) */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each row for im1 */
temp_data[j].r = local_data[i][j];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, 1);
for(j = 0; j < N; j++)
local_data[i][j] = temp_data[j].r;
}
if(task_id == 0){
time[3] = MPI_Wtime();
printf("Group 4: Inverse-2DFFT(row) takes %f s.\n", time[3] - time[2]);
}
/* Gather all the data */
MPI_Gather(local_data, chunkSize*N, MPI_FLOAT,
data, chunkSize*N, MPI_FLOAT,
0, taskcomm);
if(task_id == 0){
time[4] = MPI_Wtime();
printf("Group 4: Gathering data of Inverse-2DFFT(row) takes %f s.\n", time[4] - time[3]);
}
MPI_Scatter(data, chunkSize, column,
local_data, chunkSize, column,
0, taskcomm);
if(task_id == 0){
time[5] = MPI_Wtime();
printf("Group 4: Scattering data of columns to each processor takes %f s.\n", time[5] - time[4]);
}
/* Inverse-2DFFT(column) for output file */
for(i = 0; i < chunkSize; i++){
for(j = 0; j < N; j++){
/* FFT each column for im1 */
temp_data[j].r = local_data[j][i];
temp_data[j].i = 0;
}
c_fft1d(temp_data, N, 1);
for(j = 0; j < N; j++)
local_data[j][i] = temp_data[j].r;
}
if(task_id == 0){
time[6] = MPI_Wtime();
printf("Group 4: Inverse-2DFFT(column) takes %f s.\n", time[6] - time[5]);
}
/* Gather all the columns of output file from each rank */
MPI_Gather(local_data, chunkSize, column,
data, chunkSize, column,
0, taskcomm);
if(task_id == 0){
time[7] = MPI_Wtime();
printf("Group 4: Gathering data of Inverse-2DFFT(column) takes %f s.\n", time[7] - time[6]);
writeFile(data);
time[8] = MPI_Wtime();
printf("Group 4: Writing file to out_1 takes %f s.\n", time[8] - time[7]);
comm_time += time[7] - time[6] + time[5] - time[3] + time[2] - time[0];
comp_time += time[6] - time[5] + time[3] - time[2];
}
MPI_Comm_free(&t3_t4_comm);
}
MPI_Barrier(MPI_COMM_WORLD);
if(world_id == 0){
end = MPI_Wtime();
printf("Total communication time of 2D convolution using MPI task parallel takes %f s.\n", comm_time);
printf("Total computing time of 2D convolution using MPI task parallel takes %f s.\n", comp_time);
printf("Total running time without loading/writing of 2D convolution using MPI task parallel takes %f s.\n", comm_time + comp_time);
printf("Total running time of 2D convolution using MPI task parallel takes %f s.\n", end - start);
}
/* Free vector and task comm */
MPI_Type_free(&column);
MPI_Type_free(&col);
MPI_Comm_free(&taskcomm);
MPI_Finalize();
return 0;
}
void execute_fft(complex data[512*512], int type) {
int i, j;
for(i = 0; i < 512; i++) {
c_fft1d(&data[512 * i], 512, type);
}
}