InvXX_Dist

Advanced Analysis Library Only

AnalysisLibErrType InvXX_Dist (double probabilityXX, int degreesOfFreedom, double *xx);

Purpose

Calculates xx, given a probability (0 p < 1), such that:

prob( < x) = p

where is a random variable from a chi-square distribution with the specified degrees of freedom

Note    When p = 0, x = 0.

Example

double p, x;
n;
p = 0.635;
n = 2;
InvXX_Dist (p, n, &x);

Parameters

Input
Name	Type	Description
probabilityXX	double-precision	Input probability value (0 p < 1).
degreesOfFreedom	integer	Degrees of freedom for the chi-squared distribution.
Output
Name	Type	Description
xx	double-precision	The unique number xx such that prob( < x) = p, where is a random variable from a chi-square distribution with the specified degrees of freedom.

Return Value