/* nag_1d_cheb_intg (e02ajc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nage02.h>

int main(void)
{
  /* Initialized data */
  const double xmin = -0.5;
  const double xmax = 2.5;
  const double a[7] = { 2.53213,1.13032,0.2715,0.04434,0.00547,5.4e-4,4e-5 };

  /* Scalars */
  double ra, rb, result, xa, xb, zero;
  Integer exit_status, n, one;
  NagError fail;

 /* Arrays */
  double *aint = 0;

  INIT_FAIL(fail);
  exit_status = 0;
  Vprintf("e02ajc Example Program Results\n");

  n = 6;
  zero = 0.0;
  one = 1;

  /* Allocate memory */
  if ( !(aint = NAG_ALLOC(n + 2, double)) )
    {
      Vprintf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  e02ajc(n, xmin, xmax, a, one, zero, aint, one, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from e02ajc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  xa = 0.0;
  xb = 2.0;
  e02akc(n+1, xmin, xmax, aint, one, xa, &ra, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from e02akc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  e02akc(n+1, xmin, xmax, aint, one, xb, &rb, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from e02akc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  result = rb - ra;
  Vprintf("\n");
  Vprintf("Value of definite integral is %10.4f\n", result);
 END:
  if (aint) NAG_FREE(aint);

  return exit_status;
}