/* nag_zgelqf (f08avc) Example Program.
 *
 * Copyright 2014 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <naga02.h>
#include <nagf07.h>
#include <nagf08.h>
#include <nagx04.h>

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

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

  INIT_FAIL(fail);

  printf("nag_zgelqf (f08avc) Example Program Results\n\n");

  /* Skip heading in data file */
  scanf("%*[^\n] ");
  scanf("%ld%ld%ld%*[^\n] ", &m, &n, &nrhs);

#ifdef NAG_COLUMN_MAJOR
  pda = m;
  pdb = n;
#else
  pda = n;
  pdb = nrhs;
#endif

  tau_len = MIN(m, n);

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

  /* Read A and B 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] ");
  for (i = 1; i <= m; ++i)
    {
      for (j = 1; j <= nrhs; ++j)
        scanf(" ( %lf , %lf )", &B(i, j).re, &B(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;
    }
  /* Solve L*Y = B, storing the result in B */
  /* nag_ztrtrs (f07tsc).
   * Solution of complex triangular system of linear
   * equations, multiple right-hand sides
   */
  nag_ztrtrs(order, Nag_Lower, Nag_NoTrans, Nag_NonUnitDiag, m,
             nrhs, a, pda, b, pdb, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_ztrtrs (f07tsc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  /* Set rows (M+1) to N of B to zero */
  if (m < n)
    {
      for (i = m + 1; i <= n; ++i)
        {
          for (j = 1; j <= nrhs; ++j)
            {
              B(i, j).re = 0.0;
              B(i, j).im = 0.0;
            }
        }
    }

  /* Compute minimum-norm solution X = (Q**H)*B in B */
  /* nag_zunmlq (f08axc).
   * Apply unitary transformation determined by nag_zgelqf (f08avc)
   */
  nag_zunmlq(order, Nag_LeftSide, Nag_ConjTrans, n, nrhs, m, a, pda,
             tau, b, pdb, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_zunmlq (f08axc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Print minimum-norm solution(s) */
  /* 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, n,
                                nrhs, b, pdb, Nag_BracketForm, "%7.4f",
                                "Minimum-norm solution(s)",
                                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(a);
  NAG_FREE(b);
  NAG_FREE(tau);
  return exit_status;
}