double gammav(double x, double a, double b);
Returns the critical point of the Gamma random variable distribution function with alpha a and beta b associated with probability p.
Parameters:
x | Cummulative probability for the critical point. |
---|---|
a | Alpha shape parameter. |
b | Beta scale parameter. |
Returns:
x such that P(X ≤ x | a, b) = p
Errors:
NUMERICS_ERROR
is raised if a ≤ 0, b ≤ 0, p ≤ 0, or p ≥ 1
Usage:
double x = gammav(.5, 1.5, 2.75)
Header:
#include "contdist.h"