## RANDF Generate F-Distributed Random Variable

Section: Random Number Generation

### Usage

Generates random variables with an F-distribution. The general syntax for its use is

       y = randf(n,m)

where `n` and `m` are vectors of the number of degrees of freedom in the numerator and denominator of the chi-square random variables whose ratio defines the statistic.

### Function Internals

The statistic `F_{n,m}` is defined as the ratio of two chi-square random variables:

The PDF is given by

where `B(a,b)` is the beta function.

### Example

Here we use `randf` to generate some F-distributed random variables, and then again using the `randchi` function:

    --> randf(5*ones(1,9),7)
    ans =
      <float>  - size: [1 9]

    Columns 1 to 6
     1.194351196  0.906920850  0.755768538  1.502930284  0.062067628  1.386031985

    Columns 7 to 9
     1.816088676  0.375541776  3.579419374
    --> randchi(5*ones(1,9))./randchi(7*ones(1,9))
    ans =
      <float>  - size: [1 9]

    Columns 1 to 7
     1.3084840  1.2693102  1.0684280  0.4377135  1.1158004  0.7171145  0.4150873

    Columns 8 to 9
     1.8022333  1.4605886