betai

double betai(double a, double b, double x);

Returns the incomplete beta function Ix(a,b).

Parameters:
aFirst element of the Beta function.
bSecond element of the Beta function.
xUpper bound of integration.

Returns:
?

Errors:
NUMERICS_ERROR is raised if x < 0 or x > 1

Header:
#include "mathx.h"