/* nag_zgbtrf (f07brc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf07.h>
#include <nagx04.h>

int main(void)
{
  /* Scalars */
  Integer  i, ipiv_len, j, kl, ku, m, n, pdab;
  Integer  exit_status=0;
  NagError fail;
  Nag_OrderType order;

  /* Arrays */
  Complex  *ab=0;
  Integer  *ipiv=0;

#ifdef NAG_COLUMN_MAJOR
#define AB(I,J) ab[(J-1)*pdab + kl + ku + I - J]
  order = Nag_ColMajor;
#else
#define AB(I,J) ab[(I-1)*pdab + kl + J - I]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);
  Vprintf("f07brc Example Program Results\n\n");

  /* Skip heading in data file */
  Vscanf("%*[^\n] ");
  Vscanf("%ld%ld%ld%ld%*[^\n] ", &m, &n, &kl, &ku);
  ipiv_len = MIN(m,n);
  pdab = 2*kl + ku + 1;

  /* Allocate memory */
  if ( !(ab = NAG_ALLOC((2*kl+ku+1) * 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 <= m; ++i)
    {
      for (j = MAX(i-kl,1); j <= MIN(i+ku,n); ++j)
        Vscanf(" ( %lf , %lf )", &AB(i,j).re, &AB(i,j).im);
    }
  Vscanf("%*[^\n] ");

  /* Factorize A */
  f07brc(order, m, n, kl, ku, ab, pdab, ipiv, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from f07brc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  /* Print details of factorization */
  x04dfc(order, m, n, kl, kl+ku, ab, pdab, Nag_BracketForm,
         "%7.4f", "Details of factorization", Nag_IntegerLabels, 
         0, Nag_IntegerLabels, 0, 80, 0, 0, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from x04dfc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  /* Print pivot indices */
  Vprintf("\nIPIV\n");
  for (i = 1; i <= MIN(m,n); ++i)
    Vprintf("%3ld%s", ipiv[i-1], i%7==0 ?"\n":"               ");
  Vprintf("\n");
 END:
  if (ab) NAG_FREE(ab);
  if (ipiv) NAG_FREE(ipiv);
  return exit_status;
}