/* nag_monotonic_evaluate (e01bfc) Example Program.
 *
 * Copyright 1990 Numerical Algorithms Group
 *
 * Mark 2 revised, 1992.
 * Mark 5 revised, 1998.
 * Mark 8 revised, 2004.
 */

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nage01.h>

int main(void)
{
  Integer exit_status=0, i, m, n, r;
  NagError fail;
  double *d=0, *f=0, *pf=0, *px=0, step, *x=0;

  INIT_FAIL(fail);
  Vprintf("nag_monotonic_evaluate (e01bfc) Example Program Results\n");
  Vscanf("%*[^\n]"); /* Skip to end of line */
  Vscanf("%ld",&n);
  if (n>=2)
    {
      if ( !( d = NAG_ALLOC(n, double)) ||
           !( f = NAG_ALLOC(n, double)) ||
           !( x = NAG_ALLOC(n, double)) )
        {
          Vprintf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }
    }
  else
    {
      Vprintf("Invalid n.\n");
      exit_status = 1;
      return exit_status;
    }
  for (r = 0; r < n; r++)
    Vscanf("%lf%lf%lf",&x[r],&f[r],&d[r]);
  Vscanf("%ld",&m);
  if (m>=1)
    {
      if ( !( pf = NAG_ALLOC(m, double)) ||
           !( px = NAG_ALLOC(m, double))  )
        {
          Vprintf("Allocation failure\n");
          exit_status = -1;
          goto END;
        }
    }
  else
    {
      Vprintf("Invalid m.\n");
      exit_status = 1;
      return exit_status;
    }
  /* Compute M Equally spaced points from x[0] to x[n-1]. */
  step = (x[n-1] - x[0]) / (double)(m-1);
  for (i = 0; i < m; i++)
    px[i] = MIN(x[0]+ i*step,x[n-1]);
  /* nag_monotonic_evaluate (e01bfc).
   * Evaluation of interpolant computed by
   * nag_monotonic_interpolant (e01bec), function only
   */
  nag_monotonic_evaluate(n, x, f, d, m, px, pf, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_monotonic_evaluate (e01bfc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }
  Vprintf("                 Interpolated\n");
  Vprintf("      Abscissa      Value\n");
  for (i = 0; i < m; i++)
    Vprintf("%13.4f%13.4f\n", px[i], pf[i]);
 END:
  if (d) NAG_FREE(d);
  if (f) NAG_FREE(f);
  if (pf) NAG_FREE(pf);
  if (px) NAG_FREE(px);
  if (x) NAG_FREE(x);
  return exit_status;
}