/* nag_ztrsyl (f08qvc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#include <stdio.h>
#include <math.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagf08.h>
#include <nagf16.h>
#include <nagx04.h>
#include <nagx02.h>

int main(void)
{
  /* Scalars */
  Complex       alpha, beta;
  Integer       i, j, m, n, pda, pdb, pdc, pdd, pde, pdf;
  Integer       exit_status = 0;
  double        norm, scale;
  NagError      fail;
  Nag_OrderType order;
  Nag_SignType  sign = Nag_Minus;
  /* Arrays */
  Complex       *a = 0, *b = 0, *c = 0, *d = 0, *e = 0, *f = 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]
#define C(I, J) c[(J-1)*pdc + I - 1]
#define D(I, J) c[(J-1)*pdd + I - 1]
#define E(I, J) c[(J-1)*pde + I - 1]
#define F(I, J) c[(J-1)*pdf + 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]
#define C(I, J) c[(I-1)*pdc + J - 1]
#define D(I, J) d[(I-1)*pdd + J - 1]
#define E(I, J) e[(I-1)*pde + J - 1]
#define F(I, J) f[(I-1)*pdf + J - 1]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);

  printf("nag_ztrsyl (f08qvc) Example Program Results\n\n");

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

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

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

  /* Copy C into F */
  for(i = 1; i <= m; i++)
    {
      for(j = 1; j <= m; j++)
        {
          F(i, j).re = C(i, j).re;
          F(i, j).im = C(i, j).im;
        }
    }

  /* nag_gen_complx_mat_print_comp (x04dbc): Print matrix C */
  fflush(stdout);
  nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix, Nag_NonUnitDiag, m,
                                n, c, pdc, Nag_BracketForm, "%7.4f",
                                "Matrix C", Nag_IntegerLabels, 0,
                                Nag_IntegerLabels, 0, 80, 0, 0, &fail);
  printf("\n");
  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;
    }

  /* Reorder the Schur factorization T */
  /* nag_ztrsyl (f08qvc).
   * Solve complex Sylvester matrix equation AX + XB = C, A
   * and B are upper triangular or conjugate-transposes
   */
  nag_ztrsyl(order, Nag_NoTrans, Nag_NoTrans, sign, m, n, a, pda,
             b, pdb, c, pdc, &scale, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_ztrsyl (f08qvc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  
  /* nag_zgemm (f16zac): Compute aC - (A*X + X*B*sign) from the solution */ 
  /* and store in matrix E*/
  alpha.re = 1.0;
  alpha.im = 0.0;
  beta.re = 0.0;
  beta.im = 0.0;
  nag_zgemm(order, Nag_NoTrans, Nag_NoTrans, m, n, m, alpha, a, pda, 
            c, pdc, beta, d, pdd, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_zgemm (f16zac).\n%s\n",
             fail.message);
      exit_status = 1;
      goto END;
    }
  if(sign == Nag_Minus)
    alpha.re = -1.0;
  else
    alpha.re = 1.0;
  beta.re = 1.0;
  nag_zgemm(order, Nag_NoTrans, Nag_NoTrans, m, n, n, alpha, c, pdc, 
            b, pdb, beta, d, pdd, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_zgemm (f16zac).\n%s\n",
             fail.message);
      exit_status = 1;
      goto END;
    }
  for(i = 1; i <= m; i++)
    {
      for(j = 1; j <= n; j++)
        {
          E(i, j).re = scale * F(i, j).re - D(i, j).re;
          E(i, j).im = scale * F(i, j).im - D(i, j).im;
        }
    }

  /* nag_zge_norm (f16uac): Find norm of matrix E and print warning if */
  /* it is too large */
  nag_zge_norm(order, Nag_OneNorm, m, n, e, pde, &norm, &fail);
  if (fail.code != NE_NOERROR)
    {
      printf("Error from nag_dge_norm (f16rac).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }
  if (norm > pow(x02ajc(),0.8))
    {
      printf("%s\n%s\n","Norm of aC - (A*X + X*B*sign) is much greater than 0.",
             "Schur factorization has failed.");
    }
  else
    {
      printf(" SCALE = %11.2e\n", scale);
     }
 
 END:
  if (a) NAG_FREE(a);
  if (b) NAG_FREE(b);
  if (c) NAG_FREE(c);
  if (d) NAG_FREE(d);
  if (e) NAG_FREE(e);
  if (f) NAG_FREE(f);

  return exit_status;
}