# 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

Name | Type | Description
status | AnalysisLibErrType | A value that specifies the type of error that occurred. Refer to analysis.h for definitions of these constants.