/* nag_fft_multiple_cosine (c06hbc) Example Program.
 *
 * Copyright 1991 Numerical Algorithms Group.
 *
 * Mark 2, 1991.
 * Mark 8 revised, 2004.
 */

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


#define X(I,J) x[(I)*row_len + (J)]
int main(void)
{
  Integer exit_status=0, i, j, m, n, row_len;
  NagError fail;
  double *trig=0, *x=0;

  INIT_FAIL(fail);

  Vprintf("nag_fft_multiple_cosine (c06hbc) Example Program Results\n");
  Vscanf(" %*[^\n]");    /* Skip heading in data file */
  while (scanf("%ld %ld", &m, &n) != EOF)
    {
      if (m >=1 && n >=1)
        {
          if ( !( trig = NAG_ALLOC(2*n, double)) ||
               !( x = NAG_ALLOC(m*(n+1), double)) )
            {
              Vprintf("Allocation failure\n");
              exit_status = -1;
              goto END;
            }
        }
      else
        {
          Vprintf("Invalid m or n.\n");
          exit_status = 1;
          return exit_status;
        }
      row_len = n + 1;
      Vscanf(" %*[^\n]"); /* Skip text in data file */
      Vscanf(" %*[^\n]");
      for (i = 0; i < m; ++i)
        for (j = 0; j < row_len; ++j)
          Vscanf("%lf", &X(i,j));
      Vprintf("\nOriginal data values\n\n");
      for (i = 0; i < m; ++i)
        {
          for (j = 0; j < row_len; ++j)
            Vprintf(" %10.4f%s", X(i,j),
                    (j%7==6 && j!=row_len-1 ? "\n" : ""));
          Vprintf("\n");
        }

      /* nag_fft_init_trig (c06gzc).
       * Initialization function for other c06 functions
       */
      nag_fft_init_trig(n, trig, &fail);
      if (fail.code != NE_NOERROR)
        {
          Vprintf("Error from nag_fft_init_trig (c06gzc).\n%s\n", fail.message);
          exit_status = 1;
          goto END;
        }
      /* Initialise trig array */
      /* nag_fft_multiple_cosine (c06hbc).
       * Discrete cosine transform
       */
      nag_fft_multiple_cosine(m, n, x, trig, &fail);
      if (fail.code != NE_NOERROR)
        {
          Vprintf("Error from nag_fft_multiple_cosine (c06hbc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }
      /* Compute transform */
      Vprintf("\nDiscrete Fourier cosine transforms\n\n");
      for (i = 0; i < m; ++i)
        {
          for (j = 0; j < row_len; ++j)
            Vprintf(" %10.4f%s", X(i,j),
                    (j%7==6 && j!=row_len-1 ? "\n" : ""));
          Vprintf("\n");
        }
      /* Compute inverse transform */
      /* nag_fft_multiple_cosine (c06hbc), see above. */
      nag_fft_multiple_cosine(m, n, x, trig, &fail);
      if (fail.code != NE_NOERROR)
        {
          Vprintf("Error from nag_fft_multiple_cosine (c06hbc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }

      Vprintf("\nOriginal data as restored by inverse transform\n\n");
      for (i = 0; i < m; ++i)
        {
          for (j = 0; j < row_len; ++j)
            Vprintf(" %10.4f%s", X(i,j),
                    (j%7==6 && j!=row_len-1 ? "\n" : ""));
          Vprintf("\n");
        }
      if (trig) NAG_FREE(trig);
      if (x) NAG_FREE(x);
    }
 END:
  if (trig) NAG_FREE(trig);
  if (x) NAG_FREE(x);
  return exit_status;
}