/* nag_fft_multiple_qtr_sine (c06hcc) Example Program.
 *
 * Copyright 1991 Numerical Algorithms Group.
 *
 * Mark 2, 1991.
 * Mark 8 revised, 2004.
 */

#include <nag.h>
#include <nagx04.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagc06.h>

#define X(I, J) x[(I) *n + (J)]

int main(int argc, char *argv[])
{
  FILE     *fpin, *fpout;
  Integer  exit_status = 0, i, j, m, n;
  double   *trig = 0, *x = 0;
  NagError fail;

  INIT_FAIL(fail);

  /* Check for command-line IO options */
  fpin = nag_example_file_io(argc, argv, "-data", NULL);
  fpout = nag_example_file_io(argc, argv, "-results", NULL);

  fprintf(fpout,
          "nag_fft_multiple_qtr_sine (c06hcc) Example Program Results\n");
  fscanf(fpin, " %*[^\n]");    /* Skip heading in data file */
  while (fscanf(fpin, "%ld %ld", &m, &n) != EOF)
    {
      if (m >= 1 && n >= 1)
        {
          if (!(trig = NAG_ALLOC(2*n, double)) ||
              !(x = NAG_ALLOC(m*n, double)))
            {
              fprintf(fpout, "Allocation failure\n");
              exit_status = -1;
              goto END;
            }
        }
      else
        {
          fprintf(fpout, "\nInvalid m or n.\n");
          exit_status = 1;
          return exit_status;
        }
      fscanf(fpin, " %*[^\n]"); /* Skip text in data file */
      fscanf(fpin, " %*[^\n]");
      for (i = 0; i < m; ++i)
        for (j = 0; j < n; ++j)
          fscanf(fpin, "%lf", &X(i, j));
      fprintf(fpout, "\nOriginal data values\n\n");
      for (i = 0; i < m; ++i)
        {
          for (j = 0; j < n; ++j)
            fprintf(fpout, " %10.4f%s", X(i, j),
                    (j%7 == 6 && j != n-1?"\n":""));
          fprintf(fpout, "\n");
        }
      /* Initialise trig array */
      /* nag_fft_init_trig (c06gzc).
       * Initialization function for other c06 functions
       */
      nag_fft_init_trig(n, trig, &fail);
      if (fail.code != NE_NOERROR)
        {
          fprintf(fpout, "Error from nag_fft_init_trig (c06gzc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }

      /* Compute transform */
      /* nag_fft_multiple_qtr_sine (c06hcc).
       * Discrete quarter-wave sine transform
       */
      nag_fft_multiple_qtr_sine(Nag_ForwardTransform, m, n, x, trig, &fail);
      if (fail.code != NE_NOERROR)
        {
          fprintf(fpout,
                  "Error from nag_fft_multiple_qtr_sine (c06hcc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }

      fprintf(fpout, "\nDiscrete quarter-wave Fourier sine transforms\n\n");
      for (i = 0; i < m; ++i)
        {
          for (j = 0; j < n; ++j)
            fprintf(fpout, " %10.4f%s", X(i, j),
                    (j%7 == 6 && j != n-1?"\n":""));
          fprintf(fpout, "\n");
        }
      /* Compute inverse transform */
      /* nag_fft_multiple_qtr_sine (c06hcc), see above. */
      nag_fft_multiple_qtr_sine(Nag_BackwardTransform, m, n, x, trig, &fail);
      if (fail.code != NE_NOERROR)
        {
          fprintf(fpout,
                  "Error from nag_fft_multiple_qtr_sine (c06hcc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }

      fprintf(fpout, "\nOriginal data as restored by inverse transform\n\n");
      for (i = 0; i < m; ++i)
        {
          for (j = 0; j < n; ++j)
            fprintf(fpout, " %10.4f%s", X(i, j),
                    (j%7 == 6 && j != n-1?"\n":""));
          fprintf(fpout, "\n");
        }

 END:
      if (trig) NAG_FREE(trig);
      if (x) NAG_FREE(x);
    }

  if (fpin != stdin) fclose(fpin);
  if (fpout != stdout) fclose(fpout);
  return exit_status;
}