/* nag_zsptri (f07qwc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

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

int main(int argc, char *argv[])
{
  FILE          *fpin, *fpout;
  char          *outfile = 0;
  /* Scalars */
  Integer       ap_len, i, j, n;
  Integer       exit_status = 0;
  NagError      fail;
  Nag_UploType  uplo;
  Nag_OrderType order;
  /* Arrays */
  Integer       *ipiv = 0;
  char          nag_enum_arg[40];
  Complex       *ap = 0;

#ifdef NAG_COLUMN_MAJOR
#define A_UPPER(I, J) ap[J*(J-1)/2 + I - 1]
#define A_LOWER(I, J) ap[(2*n-J)*(J-1)/2 + I - 1]
  order = Nag_ColMajor;
#else
#define A_LOWER(I, J) ap[I*(I-1)/2 + J - 1]
#define A_UPPER(I, J) ap[(2*n-I)*(I-1)/2 + J - 1]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);

  /* Check for command-line IO options */
  fpin = nag_example_file_io(argc, argv, "-data", NULL);
  fpout = nag_example_file_io(argc, argv, "-results", NULL);
  (void) nag_example_file_io(argc, argv, "-nag_write", &outfile);
  fprintf(fpout, "nag_zsptri (f07qwc) Example Program Results\n\n");

  /* Skip heading in data file */
  fscanf(fpin, "%*[^\n] ");
  fscanf(fpin, "%ld%*[^\n] ", &n);
  ap_len = n * (n + 1)/2;

  /* Allocate memory */
  if (!(ipiv = NAG_ALLOC(n, Integer)) ||
      !(ap = NAG_ALLOC(ap_len, Complex)))
    {
      fprintf(fpout, "Allocation failure\n");
      exit_status = -1;
      goto END;
    }
  /* Read A from data file */
  fscanf(fpin, " %s%*[^\n] ", nag_enum_arg);
  /* nag_enum_name_to_value(x04nac).
   * Converts NAG enum member name to value
   */
  uplo = (Nag_UploType) nag_enum_name_to_value(nag_enum_arg);

  if (uplo == Nag_Upper)
    {
      for (i = 1; i <= n; ++i)
        {
          for (j = i; j <= n; ++j)
            fscanf(fpin, " ( %lf , %lf )", &A_UPPER(i, j).re,
                   &A_UPPER(i, j).im);
        }
      fscanf(fpin, "%*[^\n] ");
    }
  else
    {
      for (i = 1; i <= n; ++i)
        {
          for (j = 1; j <= i; ++j)
            fscanf(fpin, " ( %lf , %lf )", &A_LOWER(i, j).re,
                   &A_LOWER(i, j).im);
        }
      fscanf(fpin, "%*[^\n] ");
    }

  /* Factorize A */
  /* nag_zsptrf (f07qrc).
   * Bunch-Kaufman factorization of complex symmetric matrix,
   * packed storage
   */
  nag_zsptrf(order, uplo, n, ap, ipiv, &fail);
  if (fail.code != NE_NOERROR)
    {
      fprintf(fpout, "Error from nag_zsptrf (f07qrc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  /* Compute inverse of A */
  /* nag_zsptri (f07qwc).
   * Inverse of complex symmetric matrix, matrix already
   * factorized by nag_zsptrf (f07qrc), packed storage
   */
  nag_zsptri(order, uplo, n, ap, ipiv, &fail);
  if (fail.code != NE_NOERROR)
    {
      fprintf(fpout, "Error from nag_zsptri (f07qwc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }
  /* Print inverse */
  /* nag_pack_complx_mat_print_comp (x04ddc).
   * Print complex packed triangular matrix (comprehensive)
   */
  if (outfile) fclose(fpout);
  nag_pack_complx_mat_print_comp(order, uplo, Nag_NonUnitDiag, n, ap,
                                 Nag_BracketForm, "%7.4f", "Inverse",
                                 Nag_IntegerLabels, 0, Nag_IntegerLabels, 0,
                                 80, 0, outfile, &fail);
  if (outfile && !(fpout = fopen(outfile, "a")))
    {
      exit_status = 2;
      goto END;
    }
  if (fail.code != NE_NOERROR)
    {
      fprintf(fpout,
              "Error from nag_pack_complx_mat_print_comp (x04ddc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }
 END:
  if (fpin != stdin) fclose(fpin);
  if (fpout != stdout) fclose(fpout);
  if (ipiv) NAG_FREE(ipiv);
  if (ap) NAG_FREE(ap);

  return exit_status;
}