/* nag_zunglq (f08awc) Example Program.
 *
 * Copyright 2014 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf08.h>
#include <nagx04.h>

int main(void)
{
  /* Scalars */
  Integer       i, j, m, n, pda, tau_len;
  Integer       exit_status = 0;
  NagError      fail;
  Nag_OrderType order;
  /* Arrays */
  char          *title = 0;
  Complex       *a = 0, *tau = 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);

  printf("nag_zunglq (f08awc) Example Program Results\n\n");

  /* Skip heading in data file */
  scanf("%*[^\n] ");
  scanf("%ld%ld%*[^\n] ", &m, &n);
#ifdef NAG_COLUMN_MAJOR
  pda = m;
#else
  pda = n;
#endif
  tau_len = m;

  /* Allocate memory */
  if (!(title = NAG_ALLOC(31, char)) ||
      !(a = NAG_ALLOC(m * n, Complex)) ||
      !(tau = NAG_ALLOC(tau_len, Complex)))
    {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  /* Read A from data file */
  for (i = 1; i <= m; ++i)
    {
      for (j = 1; j <= n; ++j)
        scanf(" ( %lf , %lf )", &A(i, j).re, &A(i, j).im);
    }
  scanf("%*[^\n] ");

  /* Compute the LQ factorization of A */
  /* nag_zgelqf (f08avc).
   * LQ factorization of complex general rectangular matrix
   */
  nag_zgelqf(order, m, n, a, pda, tau, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_zgelqf (f08avc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Form the leading M rows of Q explicitly */
  /* nag_zunglq (f08awc).
   * Form all or part of unitary Q from LQ factorization
   * determined by nag_zgelqf (f08avc)
   */
  nag_zunglq(order, m, n, m, a, pda, tau, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_zunglq (f08awc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Print the leading M rows of Q only */
  sprintf(title, "The leading %2ld rows of Q\n", m);
  /* nag_gen_complx_mat_print_comp (x04dbc).
   * Print complex general matrix (comprehensive)
   */
  fflush(stdout);
  nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix, Nag_NonUnitDiag, m,
                                n, a, pda, Nag_BracketForm, "%7.4f", title,
                                Nag_IntegerLabels, 0, Nag_IntegerLabels,
                                0, 80, 0, 0, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf(
        "Error from nag_gen_complx_mat_print_comp (x04dbc).\n%s\n",
        fail.message);
      exit_status = 1;
      goto END;
    }
 END:
  NAG_FREE(title);
  NAG_FREE(a);
  NAG_FREE(tau);

  return exit_status;
}