NAG Library Manual, Mark 28.3
Interfaces:  FL   CL   CPP   AD 

NAG CL Interface Introduction
Example description
/* nag_specfun_beta_incomplete (s14ccc) Example Program.
 *
 * Copyright 2022 Numerical Algorithms Group.
 *
 * Mark 28.3, 2022.
 */

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

int main(void) {
  Integer exit_status = 0;
  double a, b, x, w, w1;
  NagError fail;

  INIT_FAIL(fail);

  printf("nag_specfun_beta_incomplete (s14ccc) Example Program Results\n");

  /* Skip heading in data file */
  scanf("%*[^\n]");

  printf("%4s%7s%7s%13s%13s\n", "a", "b", "x", "Ix(a,b)", "1-Ix(a,b)");
  while (scanf("%lf %lf %lf", &a, &b, &x) != EOF)
  {
    /* nag_specfun_beta_incomplete (s14ccc).
     * Incomplete beta function Ix(a,b) and its complement 1-Ix(a,b)
     */
    nag_specfun_beta_incomplete(a, b, x, &w, &w1, &fail);
    if (fail.code != NE_NOERROR) {
      printf("Error from nag_specfun_beta_incomplete (s14ccc).\n%s\n",
             fail.message);
      exit_status = 1;
      goto END;
    }
    printf("%6.2f%7.2f%7.2f%12.4e%12.4e\n", a, b, x, w, w1);
  }

END:
  return exit_status;
}