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From: Brian Gough <bjg@network-theory.co.uk>
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Date: Thu, 29 Nov 2001 01:08:00 -0000
To: jonathan@leto.net
Cc: gsl-discuss@sources.redhat.com
Subject: Re: sf_gamma questions
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Jonathan Leto writes:
 > Why is the error so large for gamma(x>18) ?

It's computed with an approximation so the relative error is the
appropriate measure. Note that 1/Gamma(19) is the first value which is
less than DBL_EPSILON.

 > Would it be possible to just return factorial(x-1) if gamma is
 > given an integer argument?

Sounds reasonable to me.