/* nag_ztprfs (f07uvc) 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(void)
{
  /* Scalars */
  Integer ap_len, i, j, n, nrhs;
  Integer berr_len, ferr_len, pdb, pdx;
  Integer exit_status=0;
  Nag_UploType uplo_enum;

  NagError fail;
  Nag_OrderType order;
  /* Arrays */
  char    uplo[2];
  Complex *ap=0, *b=0, *x=0;
  double  *berr=0, *ferr=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]
#define B(I,J) b[(J-1)*pdb + I - 1]
#define X(I,J) x[(J-1)*pdx + 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]
#define B(I,J) b[(I-1)*pdb + J - 1]
#define X(I,J) x[(I-1)*pdx + J - 1]
  order = Nag_RowMajor;
#endif

  INIT_FAIL(fail);
  Vprintf("nag_ztprfs (f07uvc) Example Program Results\n");
  /* Skip heading in data file */
  Vscanf("%*[^\n] ");
  Vscanf("%ld%ld%*[^\n] ", &n, &nrhs);
  berr_len = nrhs;
  ferr_len  = nrhs;
  ap_len = n * (n + 1)/2;
#ifdef NAG_COLUMN_MAJOR
  pdb = n;
  pdx = n;
#else
  pdb = nrhs;
  pdx = nrhs;
#endif

  /* Allocate memory */
  if ( !(ap = NAG_ALLOC(ap_len, Complex)) ||
       !(b = NAG_ALLOC(n * nrhs, Complex)) ||
       !(x = NAG_ALLOC(n * nrhs, Complex)) ||
       !(berr = NAG_ALLOC(berr_len, double)) ||
       !(ferr = NAG_ALLOC(ferr_len, double)) )
    {
      Vprintf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  /* Read A and B from data file, and copy B to X */
  Vscanf(" ' %1s '%*[^\n] ", uplo);
  if (*(unsigned char *)uplo == 'L')
    uplo_enum = Nag_Lower;
  else if (*(unsigned char *)uplo == 'U')
    uplo_enum = Nag_Upper;
  else
    {
      Vprintf("Unrecognised character for Nag_UploType type\n");
      exit_status = -1;
      goto END;
    }
  if (uplo_enum == Nag_Upper)
    {
      for (i = 1; i <= n; ++i)
        {
          for (j = i; j <= n; ++j)
            Vscanf(" ( %lf , %lf )", &A_UPPER(i,j).re, &A_UPPER(i,j).im);
        }
      Vscanf("%*[^\n] ");
    }
  else
    {
      for (i = 1; i <= n; ++i)
        {
          for (j = 1; j <= i; ++j)
            Vscanf(" ( %lf , %lf )", &A_LOWER(i,j).re, &A_LOWER(i,j).im);
        }
      Vscanf("%*[^\n] ");
    }
  for (i = 1; i <= n; ++i)
    {
      for (j = 1; j <= nrhs; ++j)
        Vscanf(" ( %lf , %lf )", &B(i,j).re, &B(i,j).im);
    }
  Vscanf("%*[^\n] ");
  for (i = 1; i <= n; ++i)
    {
      for (j = 1; j <= nrhs; ++j)
        {
          X(i,j).re = B(i,j).re;
          X(i,j).im = B(i,j).im;
        }
    }
  /* Compute solution in the array X */
  /* nag_ztptrs (f07usc).
   * Solution of complex triangular system of linear
   * equations, multiple right-hand sides, packed storage
   */
  nag_ztptrs(order, uplo_enum, Nag_NoTrans, Nag_NonUnitDiag, n,
             nrhs, ap, x, pdx, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_ztptrs (f07usc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Compute backward errors and estimated bounds on the */
  /* forward errors */
  /* nag_ztprfs (f07uvc).
   * Error bounds for solution of complex triangular system of
   * linear equations, multiple right-hand sides, packed
   * storage
   */
  nag_ztprfs(order, uplo_enum, Nag_NoTrans, Nag_NonUnitDiag, n,
             nrhs, ap, b, pdb, x, pdx, ferr, berr, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_ztprfs (f07uvc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  /* Print solution */
  Vprintf("\n");
  /* nag_gen_complx_mat_print_comp (x04dbc).
   * Print complex general matrix (comprehensive)
   */
  nag_gen_complx_mat_print_comp(order, Nag_GeneralMatrix, Nag_NonUnitDiag, n,
                                nrhs, x, pdx, Nag_BracketForm, "%7.4f",
                                "Solution(s)", Nag_IntegerLabels, 0,
                                Nag_IntegerLabels, 0, 80, 0, 0, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_gen_complx_mat_print_comp (x04dbc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }
  Vprintf("\nBackward errors (machine-dependent)\n");
  for (j = 1; j <= nrhs; ++j)
    Vprintf("%11.1e%s", berr[j-1], j%4==0 ?"\n":" ");
  Vprintf("\nEstimated forward error bounds "
          "(machine-dependent)\n");
  for (j = 1; j <= nrhs; ++j)
    Vprintf("%11.1e%s", ferr[j-1], j%4==0 ?"\n":" ");
  Vprintf("\n");
 END:
  if (ap) NAG_FREE(ap);
  if (b) NAG_FREE(b);
  if (x) NAG_FREE(x);
  if (berr) NAG_FREE(berr);
  if (ferr) NAG_FREE(ferr);

  return exit_status;
}