##
F_CVF

The
F_CVF
function computes the
cutoff value *
V*
in an
F distribution with *
Dfn*
and*
Dfd *
degrees of freedom such that the probability that a random variable *
X*
is greater than *
V*
is equal to a user-supplied probability *
P*
.

This routine is written in the IDL language. Its source code can be found in the file ```
f_cvf.pro
```

in the ```
lib
```

subdirectory of the IDL distribution.

###
Calling Sequence

Result = F_CVF(*
P, Dfn, Dfd*
)

###
Arguments

####
P

A non-negative single- or double-precision floating-point scalar, in the interval [0.0, 1.0], that specifies the probability of occurrence or success.

####
Dfn

A positive integer, single- or double-precision floating-point scalar that specifies the number of degrees of freedom of the F distribution numerator.

####
Dfd

A positive integer, single- or double-precision floating-point scalar that specifies the number of degrees of freedom of the F distribution denominator.

###
Example

Use the following command to compute the cutoff value in an F distribution with ten degrees of freedom in the numerator and six degrees of freedom in the denominator such that the probability that a random variable X is greater than the cutoff value is 0.01. The result should be 7.87413.

PRINT, F_CVF(0.01, 10, 6)

IDL prints:

7.87413