Dear Win,

I you look at the definition of the F-distribution you'll see a ratio of gamma functions. Computing gamma(200) will overflow most engines, so what you need is some indirect method for computing the ratio.

Now if you read the docs you'll see that Statistics::Distributions is not intended for high precision work (though your issue isn't exactly precision) and that the authors direct you to a website for more sophisticated algorithms.

You might also reconsider why you need to be evaluating the F-distribution at such extreme parameters. Maybe you can save yourself the trouble of dealing with asymptotics.

In reply to Re: Very small numbers by RandomWalk
in thread Very small numbers by Win

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