Functions and CALL Routines 
Returns a quantile from the F distribution.

p

is a numeric probability.
Range: 
0 p
< 1 

ndf

is a numeric numerator degrees of freedom
parameter.

ddf

is a numeric denominator degrees of freedom
parameter.

nc

is an optional numeric noncentrality parameter.
Range: 
nc 0 
The FINV function returns the p^{th} quantile from the F distribution
with numerator degrees of freedom ndf, denominator degrees of
freedom ddf, and noncentrality parameter nc. The
probability that an observation from the F distribution is less
than the quantile is p. This function accepts noninteger degrees
of freedom parameters ndf and ddf.
If the optional parameter nc is not specified
or has the value 0, the quantile from the central F distribution
is returned. The noncentrality parameter nc is defined such that
if X and Y are normal random variables with means and 0,
respectively, and variance 1, then
has a noncentral F distribution with nc = ^{2}.
 CAUTION:

For large values of nc, the algorithm could fail. In that case, a missing value is
returned.
Note: FINV is the inverse of the PROBF function.
These statements compute the 95^{th}
quantile value of a central F distribution with 2 and 10 degrees
of freedom and a noncentral F distribution with 2 and 10.3 degrees
of freedom and a noncentrality parameter equal to 2:
SAS Statements 
Results 
q1=finv(.95,2,10);

4.1028210151

q2=finv(.95,2,10.3,2);

7.583766024

Copyright © 2011 by SAS Institute Inc., Cary, NC, USA. All rights reserved.