/* nag_zgbbrd (f08lsc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf08.h>

int main(void)
{
  /* Scalars */
  Integer  i, j, kl, ku, m, n, ncc, pdab, pdc, pdq, pdpt;
  Integer  d_len, e_len;
  Integer  exit_status=0;
  NagError fail;
  Nag_OrderType order;
  /* Arrays */
  Complex *ab=0, *c=0, *pt=0, *q=0;
  double  *d=0, *e=0;

#ifdef NAG_COLUMN_MAJOR
#define AB(I,J) ab[(J-1)*pdab + 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("nag_zgbbrd (f08lsc) Example Program Results\n");

  /* Skip heading in data file */
  Vscanf("%*[^\n] ");
  Vscanf("%ld%ld%ld%ld%ld%*[^\n] ",
         &m, &n, &kl, &ku, &ncc);
#ifdef NAG_COLUMN_MAJOR
  pdab = kl + ku + 1;
  pdq = m;
  pdpt = n;
  pdc = m;
#else
  pdab = kl + ku + 1;
  pdq = m;
  pdpt = n;
  pdc = MAX(1,ncc);
#endif
  d_len = MIN(m,n);
  e_len = MIN(m,n)-1;

  /* Allocate memory */
  if ( !(ab = NAG_ALLOC((kl+ku+1) * m, Complex)) ||
       !(c = NAG_ALLOC(m * MAX(1,ncc), Complex)) ||
       !(d = NAG_ALLOC(d_len, double)) ||
       !(e = NAG_ALLOC(e_len, double)) ||
       !(pt = NAG_ALLOC(n * n, Complex)) ||
       !(q = NAG_ALLOC(m * m, Complex)) )
    {
      Vprintf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  /* Read A from data file */
  for (i = 1; i <= m; ++i)
    {
      for (j = MAX(1,i-kl); j <= MIN(n,i+ku); ++j)
        Vscanf(" ( %lf , %lf )", &AB(i,j).re, &AB(i,j).im);
    }
  Vscanf("%*[^\n] ");
  /* Reduce A to bidiagonal form */
  /* nag_zgbbrd (f08lsc).
   * Reduction of complex rectangular band matrix to upper
   * bidiagonal form
   */
  nag_zgbbrd(order, Nag_DoNotForm, m, n, ncc, kl, ku, ab,
             pdab, d, e, q, pdq, pt, pdpt, c, pdc, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_zgbbrd (f08lsc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Print bidiagonal form */
  Vprintf("\nDiagonal\n");
  for (i = 1; i <= MIN(m,n); ++i)
    Vprintf("%9.4f%s", d[i-1], i%8==0 ?"\n":" ");
  if (m >= n)
    Vprintf("\nSuper-diagonal\n");
  else
    Vprintf("\nSub-diagonal\n");
  for (i = 1; i <= MIN(m,n) - 1; ++i)
    Vprintf("%9.4f%s", e[i-1], i%8==0 ?"\n":" ");
  Vprintf("\n");

 END:
  if (ab) NAG_FREE(ab);
  if (c) NAG_FREE(c);
  if (d) NAG_FREE(d);
  if (e) NAG_FREE(e);
  if (pt) NAG_FREE(pt);
  if (q) NAG_FREE(q);

  return exit_status;
}