/* nag_multid_quad_adapt_1 (d01wcc) Example Program.
 *
 * Copyright 1998 Numerical Algorithms Group.
 *
 * Mark 5, 1998.
 * Mark 7 revised, 2001.
 *
 */

#include <nag.h>
#include <nagx04.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <math.h>
#include <nagd01.h>

#ifdef __cplusplus
extern "C" {
#endif
static double NAG_CALL f(Integer n, double z[], Nag_User *comm);
#ifdef __cplusplus
}
#endif

#define NDIM   4
#define MAXPTS 1000*NDIM

int main(int argc, char *argv[])
{
  FILE     *fpout;
  Integer  exit_status = 0;
  Integer  ndim = NDIM;
  Integer  maxpts = MAXPTS;
  double   a[4], b[4];
  Integer  k;
  double   finval;
  Integer  minpts;
  double   acc, eps;
  Nag_User comm;
  NagError fail;

  INIT_FAIL(fail);

  /* Check for command-line IO options */
  fpout = nag_example_file_io(argc, argv, "-results", NULL);
  fprintf(fpout, "nag_multid_quad_adapt_1 (d01wcc) Example Program Results\n");
  for (k = 0; k < 4; ++k)
    {
      a[k] = 0.0;
      b[k] = 1.0;
    }
  eps = 0.0001;
  minpts = 0;

  /* nag_multid_quad_adapt_1 (d01wcc).
   * Multi-dimensional adaptive quadrature, thread-safe
   */
  nag_multid_quad_adapt_1(ndim, f, a, b, &minpts, maxpts, eps, &finval, &acc,
                          &comm, &fail);

  if (fail.code != NE_NOERROR && fail.code != NE_QUAD_MAX_INTEGRAND_EVAL)
    {
      fprintf(fpout, "Error from nag_multid_quad_adapt_1 (d01wcc) %s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }
  fprintf(fpout, "Requested accuracy =%12.2e\n", eps);
  fprintf(fpout, "Estimated value    =%12.4f\n", finval);
  fprintf(fpout, "Estimated accuracy =%12.2e\n", acc);

 END:
  if (fpout != stdout) fclose(fpout);
  return exit_status;
}


static double NAG_CALL f(Integer n, double z[], Nag_User *comm)
{
  double tmp_pwr;
  tmp_pwr = z[1]+1.0+z[n-1];
  return z[0]*4.0*z[2]*z[2]*exp(z[0]*2.0*z[2])/(tmp_pwr*tmp_pwr);
}