/* nag_lapackeig_ztgexc (f08ytc) Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 *
 * Mark 30.1, 2024.
 */

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

int main(void) {
  /* Scalars */
  Integer i, ifst, ilst, j, n, pdq, pds, pdt, pdz;
  Integer exit_status = 0;

  /* Arrays */
  Complex *q = 0, *s = 0, *t = 0, *z = 0;
  char nag_enum_arg[40];

  NagError fail;
  Nag_OrderType order;
  Nag_Boolean wantq, wantz;
  Nag_MatrixType upmat = Nag_UpperMatrix;
  Nag_DiagType diag = Nag_NonUnitDiag;
  Nag_LabelType intlab = Nag_IntegerLabels;
  Nag_ComplexFormType brac = Nag_BracketForm;

#ifdef NAG_COLUMN_MAJOR
#define S(I, J) s[(J - 1) * pds + I - 1]
#define T(I, J) t[(J - 1) * pdt + I - 1]
  order = Nag_ColMajor;
#else
#define S(I, J) s[(I - 1) * pds + J - 1]
#define T(I, J) t[(I - 1) * pdt + J - 1]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);

  printf("nag_lapackeig_ztgexc (f08ytc) Example Program Results\n\n");

  /* Skip heading in data file */
  scanf("%*[^\n]");
  scanf("%" NAG_IFMT "%*[^\n]", &n);
  if (n < 0) {
    printf("Invalid n\n");
    exit_status = 1;
    goto END;
  }
  scanf(" %39s%*[^\n]", nag_enum_arg);
  /* nag_enum_name_to_value (x04nac).
   * Converts NAG enum member name to value
   */
  wantq = (Nag_Boolean)nag_enum_name_to_value(nag_enum_arg);
  scanf(" %39s%*[^\n]", nag_enum_arg);
  wantz = (Nag_Boolean)nag_enum_name_to_value(nag_enum_arg);

  pds = n;
  pdt = n;
  pdq = (wantq ? n : 1);
  pdz = (wantz ? n : 1);

  /* Allocate memory */
  if (!(s = NAG_ALLOC(n * n, Complex)) || !(t = NAG_ALLOC(n * n, Complex)) ||
      !(q = NAG_ALLOC(pdq * pdq, Complex)) ||
      !(z = NAG_ALLOC(pdz * pdz, Complex))) {
    printf("Allocation failure\n");
    exit_status = -1;
    goto END;
  }

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

  /* Read the row indices */
  scanf("%" NAG_IFMT "%" NAG_IFMT "%*[^\n]", &ifst, &ilst);

  /* Reorder the S and T */
  nag_lapackeig_ztgexc(order, wantq, wantz, n, s, pds, t, pdt, q, pdq, z, pdz,
                       ifst, &ilst, &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_lapackeig_ztgexc (f08ytc).\n%s\n", fail.message);
    exit_status = 1;
    goto END;
  }

  /* Print reordered generalized Schur form */
  fflush(stdout);
  nag_file_print_matrix_complex_gen_comp(order, upmat, diag, n, n, s, pds, brac,
                                         "%7.4f", "Reordered Schur matrix S",
                                         intlab, NULL, intlab, NULL, 80, 0,
                                         NULL, &fail);
  if (fail.code != NE_NOERROR)
    goto PRERR;
  printf("\n");
  fflush(stdout);
  nag_file_print_matrix_complex_gen_comp(order, upmat, diag, n, n, t, pdt, brac,
                                         "%7.4f", "Reordered Schur matrix T",
                                         intlab, NULL, intlab, NULL, 80, 0,
                                         NULL, &fail);
PRERR:
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_file_print_matrix_complex_gen_comp (x04dbc).\n%s\n",
           fail.message);
    exit_status = 1;
  }

END:
  NAG_FREE(q);
  NAG_FREE(s);
  NAG_FREE(t);
  NAG_FREE(z);

  return exit_status;
}