/* nag_zgecon (f07auc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <naga02.h>
#include <nagf07.h>
#include <nagf16.h>
#include <nagx02.h>
#include <math.h>

int main(void)
{

  /* Scalars */
  double   anorm, rcond;
  Integer  exit_status=0;
  Integer  i, ipiv_len,j, n, pda;
  NagError fail;
  Nag_OrderType order;
  /* Arrays */
  Complex  *a=0;
  Integer  *ipiv=0;

#ifdef NAG_COLUMN_MAJOR
#define A(I,J) a[(J-1)*pda + I - 1]
  order = Nag_ColMajor;
#else
#define A(I,J) a[(I-1)*pda + J - 1]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);
  Vprintf("f07auc Example Program Results\n\n");
  /* Skip heading in data file */
  Vscanf("%*[^\n] ");
  Vscanf("%ld%*[^\n] ", &n);

#ifdef NAG_COLUMN_MAJOR
  pda = n;
#else
  pda = n;
#endif
  ipiv_len = n;

  /* Allocate memory */
  if ( !(a = NAG_ALLOC(n * n, Complex)) ||
       !(ipiv = NAG_ALLOC(ipiv_len, Integer)) )
    {
      Vprintf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  /* Read A from data file */
  for (i = 1; i <= n; ++i)
    {
      for (j = 1; j <= n; ++j)
        Vscanf(" ( %lf , %lf )", &A(i,j).re, &A(i,j).im);
    }
  Vscanf("%*[^\n] ");
  /* Compute norm of A */
  f16uac(order, Nag_OneNorm, n, n, a, pda, &anorm, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from f16uac.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Factorize A */
  f07arc(order, n, n, a, pda, ipiv, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from f07arc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  /* Estimate condition number */
  f07auc(order, Nag_OneNorm, n, a, pda, anorm, &rcond, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from f07auc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  if (rcond >= X02AJC)
    Vprintf("Estimate of condition number = %10.2e\n",1.0/rcond);
  else
    Vprintf("A is singular to working precision\n");
 END:
  if (a) NAG_FREE(a);
  if (ipiv) NAG_FREE(ipiv);
  return exit_status;
}