/* nag_complex_form_q (f01rec) Example Program.
 *
 * Copyright 1990 Numerical Algorithms Group.
 *
 * Mark 1, 1990.
 * Mark 8 revised, 2004.
 */

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagf01.h>

#define COMPLEX(A) A.re, A.im
#define A(I,J) a[(I)*tda + J]
#define Q(I,J) q[(I)*tdq + J]

int main(void)
{
  Complex *a=0, *q=0, *theta=0;
  Integer exit_status=0, i, j, m, n, ncolq, tda, tdq;
  NagError fail;

  INIT_FAIL(fail);
  Vprintf("nag_complex_form_q (f01rec) Example Program Results\n");
  /* Skip heading in data file */
  Vscanf("%*[^\n]");
  Vscanf("%ld%ld", &m, &n);
  if (n>=0 && m>=n)
    {
      if ( !( a = NAG_ALLOC(m*n, Complex)) ||
           !( q = NAG_ALLOC(m*m, Complex)) ||
           !( theta = NAG_ALLOC(m, Complex)) )
        {
          Vprintf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }
      tda = n;
      tdq = m;
    }
  else
    {
      Vprintf("Invalid n or m.\n");
      exit_status = 1;
      return exit_status;
    }
  for (i=0; i<m; ++i)
    for(j=0; j<n; ++j)
      Vscanf(" ( %lf,  %lf ) ", COMPLEX(&A(i,j)));
  /* Find the QR factorization of A. */
  /* nag_complex_qr (f01rcc).
   * QR factorization of complex m by n matrix (m~>=~n)
   */
  nag_complex_qr(m, n, a, tda, theta, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_complex_qr (f01rcc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  /* Copy the array A into Q and form the m by m matrix Q. */
  for (j=0; j<n; ++j)
    for (i=0; i<m; ++i)
      Q(i,j).re = A(i,j).re, Q(i,j).im = A(i,j).im;
  ncolq = m;
  /* nag_complex_form_q (f01rec).
   * Form columns of Q after factorization by nag_complex_qr
   * (f01rcc)
   */
  nag_complex_form_q(Nag_ElementsSeparate, m, n, ncolq, q, tdq,
                     theta, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_complex_form_q (f01rec).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  Vprintf("\nMatrix  Q\n");
  for (i=0; i<m; ++i)
    {
      for (j=0; j<ncolq; ++j)
        Vprintf(" (%5.2f,%5.2f)%s", COMPLEX(Q(i,j)),
                (j%5==4 || j==ncolq-1) ? "\n" : " ");
    }
 END:
  if (a) NAG_FREE(a);
  if (q) NAG_FREE(q);
  if (theta) NAG_FREE(theta);
  return exit_status;
}