/* nag_fft_3d (c06pxc) Example Program.
*
* Copyright 2014 Numerical Algorithms Group.
*
* Mark 7, 2002.
*/
#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagc06.h>
#include <nagx04.h>
static Integer writex(Integer n1, Integer n2, Integer n3, Complex *x)
{
/* Routine to print 3D matrix in 2D slices. */
Integer k;
NagError fail;
INIT_FAIL(fail);
for (k = 1; k <= n3; k++)
{
char title[30];
sprintf(title, "X(i,j,k) for k = %" NAG_IFMT, k);
fflush(stdout);
nag_gen_complx_mat_print_comp(Nag_ColMajor, Nag_GeneralMatrix,
Nag_NonUnitDiag, n1, n2, &x[(k-1)*n1*n2],
n1,
Nag_BracketForm, "%6.3f",
title, Nag_NoLabels, 0,
Nag_NoLabels, 0, 90, 0, 0,
&fail);
printf("\n");
}
if (fail.code != NE_NOERROR)
{
printf(
"Error from nag_gen_complx_mat_print_comp (x04dbc).\n%s\n",
fail.message);
return 1;
}
return 0;
}
int main(void)
{
/* Scalars */
Integer i, j, k, n1, n2, n3;
Integer exit_status = 0;
NagError fail;
/* Arrays */
Complex *x = 0;
#define X(I, J, K) x[(K-1)*n2*n1 + (J-1)*n1 + I - 1]
INIT_FAIL(fail);
printf("nag_fft_3d (c06pxc) Example Program Results\n");
/* Skip heading in data file */
scanf("%*[^\n]");
scanf("%ld%ld%ld", &n1, &n2, &n3);
scanf("%*[^\n]");
if (n1*n2*n3 >= 1)
{
/* Allocate memory */
if (!(x = NAG_ALLOC(n1 * n2 * n3, Complex)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
/* Read in complex data and print out. */
for (k = 1; k <= n3; ++k)
{
for (i = 1; i <= n1; ++i)
{
for (j = 1; j <= n2; ++j)
{
scanf(" ( %lf, %lf ) ", &X(i, j, k).re,
&X(i, j, k).im);
}
}
}
printf("\nOriginal data values\n\n");
exit_status = writex(n1, n2, n3, x);
if (exit_status != 0)
{
goto END;
}
/* Compute transform */
/* nag_fft_3d (c06pxc).
* Three-dimensional complex discrete Fourier transform,
* complex data format
*/
nag_fft_3d(Nag_ForwardTransform, n1, n2, n3, x, &fail);
if (fail.code != NE_NOERROR)
{
printf("Error from nag_fft_3d (c06pxc).\n%s\n", fail.message);
exit_status = 1;
goto END;
}
printf("\nComponents of discrete Fourier transforms\n\n");
exit_status = writex(n1, n2, n3, x);
if (exit_status != 0)
{
goto END;
}
/* Compute inverse transform */
/* nag_fft_3d (c06pxc), see above. */
nag_fft_3d(Nag_BackwardTransform, n1, n2, n3, x, &fail);
if (fail.code != NE_NOERROR)
{
printf("Error from nag_fft_3d (c06pxc).\n%s\n", fail.message);
exit_status = 1;
goto END;
}
printf("\nOriginal data as restored by inverse transform\n\n");
exit_status = writex(n1, n2, n3, x);
}
else
printf("\nInvalid value of n1, n2 or n3.\n");
END:
NAG_FREE(x);
return exit_status;
}