/* nag_sum_fft_real_2d (c06pvc) Example Program.
*
* Copyright 2021 Numerical Algorithms Group.
*
* Mark 27.3, 2021.
*/
#include <nag.h>
#include <stdio.h>
int main(void) {
/* Scalars */
Integer exit_status = 0, i, m, n;
/* Arrays */
Complex *y = 0;
double *x = 0;
char title[60];
/* Nag Types */
NagError fail;
INIT_FAIL(fail);
printf("nag_sum_fft_real_2d (c06pvc) Example Program Results\n");
fflush(stdout);
/* Read dimensions of array from data file. */
scanf("%*[^\n]%" NAG_IFMT "%" NAG_IFMT "%*[^\n]", &m, &n);
if (!(x = NAG_ALLOC(m * n, double)) ||
!(y = NAG_ALLOC((m / 2 + 1) * n, Complex))) {
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
/* Read array values from data file and print out. */
for (i = 0; i < m * n; i++)
scanf("%lf", &x[i]);
sprintf(title, "\n Original data values\n");
nag_file_print_matrix_real_gen_comp(
Nag_RowMajor, Nag_GeneralMatrix, Nag_NonUnitDiag, n, m, x, m, "%6.3f",
title, Nag_NoLabels, 0, Nag_NoLabels, 0, 80, 0, NULL, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_file_print_matrix_real_gen_comp (x04cbc).\n%s\n",
fail.message);
exit_status = 1;
goto END;
}
/* Compute two-dimensional real-to-complex discrete Fourier transform using
* nag_sum_fft_real_2d (c06pvc) and print out.
*/
nag_sum_fft_real_2d(m, n, x, y, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_sum_fft_real_2d (c06pvc).\n%s\n", fail.message);
exit_status = 2;
goto END;
}
sprintf(title, "\n Components of discrete Fourier transform\n");
nag_file_print_matrix_complex_gen_comp(
Nag_RowMajor, Nag_GeneralMatrix, Nag_NonUnitDiag, n, m / 2 + 1, y,
m / 2 + 1, Nag_BracketForm, "%6.3f", title, Nag_NoLabels, 0, Nag_NoLabels,
0, 80, 0, NULL, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_file_print_matrix_complex_gen_comp (x04dbc).\n%s\n",
fail.message);
exit_status = 3;
goto END;
}
/* Compute two-dimensional complex-to-real discrete Fourier transform using
* nag_sum_fft_hermitian_2d (c06pwc) and print out.
*/
nag_sum_fft_hermitian_2d(m, n, y, x, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_sum_fft_hermitian_2d (c06pwc).\n%s\n", fail.message);
exit_status = 4;
goto END;
}
sprintf(title, "\n Original sequence as restored by inverse transform\n");
nag_file_print_matrix_real_gen_comp(
Nag_RowMajor, Nag_GeneralMatrix, Nag_NonUnitDiag, n, m, x, m, "%6.3f",
title, Nag_NoLabels, 0, Nag_NoLabels, 0, 80, 0, NULL, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_file_print_matrix_real_gen_comp (x04cbc).\n%s\n",
fail.message);
exit_status = 5;
goto END;
}
END:
NAG_FREE(x);
NAG_FREE(y);
return exit_status;
}