/* nag_gamma_pdf (g01kfc) Example Program.
 *
 * Copyright 2009, Numerical Algorithms Group.
 *
 * Mark 9, 2009.
 */

/* Pre-processor includes */
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <nag.h>
#include <nagx04.h>
#include <nag_stdlib.h>
#include <nagg01.h>

int main(int argc, char *argv[])
{
  FILE     *fpin, *fpout;
  /*Integer scalar and array declarations */
  Integer  exit_status = 0;
  Integer  i, ndata;
  /*Double scalar and array declarations */
  double   a, b, f, x;
  /*Nag Types */
  NagError fail;

  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);
  fprintf(fpout, "nag_gamma_pdf (g01kfc) Example Program Results\n\n");
  fscanf(fpin, "%*[^\n] ");
  fscanf(fpin, "%ld%*[^\n] ", &ndata);
  fprintf(fpout, "%14s%16s%16s%16s\n\n", "X", "A", "B", "RESULT");
  for (i = 0; i < ndata; i++)
    {
      fscanf(fpin, "%lf%lf%lf%*[^\n] ", &x, &a, &b);
      /*
       * nag_gamma_pdf (g01kfc)
       * Calculates the value for the probability density function of
       * the gamma distribution at a chosen point.
       */
      f = nag_gamma_pdf(x, a, b, &fail);
      if (fail.code != NE_NOERROR)
        {
          fprintf(fpout, "Error from nag_gamma_pdf (g01kfc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }
      fprintf(fpout, "%18.4e%16.4e%16.4e%16.4e\n", x, a, b, f);
    }

 END:
  if (fpin != stdin) fclose(fpin);
  if (fpout != stdout) fclose(fpout);

  return exit_status;
}