/*******************************************************

* Copyright (c) 2014, ArrayFire

* All rights reserved.

*

* This file is distributed under 3-clause BSD license.

* The complete license agreement can be obtained at:

* http://arrayfire.com/licenses/BSD-3-Clause

********************************************************/

#include <arrayfire.h>

#include <stdio.h>

#include <math.h>

#include <cstdlib>

using namespace af;

// create a small wrapper to benchmark

static array A; // populated before each timing

static void fn()

{

array B = fft2(A); // matrix multiply

B.eval(); // ensure evaluated

}

int main(int argc, char ** argv)

{

try {

int device = argc > 1 ? atoi(argv[1]) : 0;

setDevice(device);

info();

printf("Benchmark N-by-N 2D fft\n");

for (int M = 7; M <= 12; M++) {

int N = (1 << M);

printf("%4d x %4d: ", N, N);

A = randu(N,N);

double time = timeit(fn); // time in seconds

double gflops = 10.0 * N * N * M / (time * 1e9);

printf(" %4.0f Gflops\n", gflops);

fflush(stdout);

}

} catch (af::exception& e) {

fprintf(stderr, "%s\n", e.what());

}

return 0;

}