PROBCHI Function

Returns the probability from a chi-square distribution.

Category:	Probability
Returned data type:	DOUBLE

Table of Contents

Syntax

PROBCHI(x, df[, nc])

Required Arguments

x

is a numeric random variable.

Range	x ≥ 0
Data type	DOUBLE

df

is a numeric degrees of freedom parameter.

Range	df > 0
Data type	DOUBLE

Optional Argument

nc

is an optional numeric noncentrality parameter.

Range	nc ≥ 0
Data type	DOUBLE

Details

The PROBCHI function returns the probability that an observation from a chi-square distribution, with degrees of freedom df and noncentrality parameter nc, is less than or equal to x. This function accepts a noninteger degrees of freedom parameter df. If the optional parameter nc is not specified or has the value 0, the value returned is from the central chi-square distribution.

Example

The following program illustrates the PROBCHI function:

Note: In this example, DS2 statements are sent to SAS using PROC DS2.

proc ds2;
data _null_; 
   dcl double x;
   method run();
      x=probchi(11.264,11);
      put x= ;
   end;
enddata;
run;
quit;

proc ds2;
data _null_; 
   dcl double x;
   method run();
      x=probchi(11.264,11);
      put x= ;
   end;
enddata;
run;
quit;

SAS writes the following output to the log:

0.5785813293173

Last updated: September 2, 2026