[ChangeSet] Beta function...

[David Bateman]

Ben Abbott wrote:
>
> On Mar 17, 2008, at 3:40 PM, Ben Abbott wrote:
>
>> On Monday, March 17, 2008, at 02:56PM, "Jorge Londoño"
>> <jmlon at yahoo.com> wrote:
>>> I just happen to jump into a problem that require me to compute the
>>> Beta function with negative arguments.
>>> If you look at the definition of the beta function, for example here:
>>
>
> I replaced gammaln(x) with log(gamma(x)), modified the help text to
> reflect that inputs must be real, and added a few extra tests.
>
> Ben

Is that the right (TM) thing to do, as Marco says it increases the risk
of overflows? Shouldn't we rather get lgamma to work correctly for
negative arguments. What about something like the attached patch instead?

D.

-- 
David Bateman                                David.Bateman at motorola.com
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