/* nag_complex_lu (f03ahc) Example Program.
 *
 * Copyright 1990 Numerical Algorithms Group.
 *
 * Mark 1A revised, (Oct 1990).
 * Mark 8 revised, 2004.
 */

#include <nag.h>
#include <nagx04.h>
#include <math.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagf03.h>

#define A(I, J) a[(I) *tda + J]

int main(int argc, char *argv[])
{
  FILE     *fpin, *fpout;

  Complex  *a = 0, det;
  Integer  dete, exit_status = 0, i, j, n, *pivot = 0, tda;
  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_complex_lu (f03ahc) Example Program Results\n");
  fscanf(fpin, "%*[^\n]"); /* Skip heading in data file */

  fscanf(fpin, "%ld", &n);
  if (n >= 1)
    {
      if (!(pivot = NAG_ALLOC(n, Integer)) ||
          !(a = NAG_ALLOC(n*n, Complex)))
        {
          fprintf(fpout, "Allocation failure\n");
          exit_status = -1;
          goto END;
        }
      tda = n;
    }
  else
    {
      fprintf(fpout, "Invalid n.\n");
      exit_status = 1;
      return exit_status;
    }
  for (i = 0; i < n; i++)
    for (j = 0; j < n; j++)
      fscanf(fpin, " ( %lf,  %lf ) ", &A(i, j).re, &A(i, j).im);
  /* nag_complex_lu (f03ahc).
   * LU factorization and determinant of complex matrix
   */
  nag_complex_lu(n, a, tda, pivot, &det, &dete, &fail);
  if (fail.code != NE_NOERROR)
    {
      fprintf(fpout, "Error from nag_complex_lu (f03ahc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  else
    {
      fprintf(fpout, "Array a after factorization\n");
      for (i = 0; i < n; i++)
        {
          for (j = 0; j < n; j++)
            fprintf(fpout, "(%7.3f, %7.3f) ", A(i, j).re, A(i, j).im);
          fprintf(fpout, "\n");
        }
      fprintf(fpout, "\nArray pivot\n");
      for (i = 0; i < n; i++)
        fprintf(fpout, "%5ld", pivot[i]);
      fprintf(fpout, "\n\ndet.re = %7.4f, det.im = %7.4f, dete = %2ld.\n",
              det.re, det.im, dete);
      det.re = ldexp(det.re, (int) dete);
      det.im = ldexp(det.im, (int) dete);
      fprintf(fpout, "\nValue of determinant = (%7.4f, %7.4f)\n", det.re,
              det.im);
    }
 END:
  if (fpin != stdin) fclose(fpin);
  if (fpout != stdout) fclose(fpout);
  if (pivot) NAG_FREE(pivot);
  if (a) NAG_FREE(a);
  return exit_status;
}