From help-octave-request at bevo dot che dot wisc dot edu Tue Mar 25 16:36:45 2003
Subject: Re: Problems with gamma, lgamma, and alternatives
From: Mike Miller <mbmiller at taxa dot epi dot umn dot edu>
To: michael dot creel at uab dot es
cc: Help-Octave List <help-octave at bevo dot che dot wisc dot edu>
Date: Tue, 25 Mar 2003 16:36:36 -0600 (CST)

On Tue, 25 Mar 2003, Mike Miller wrote:

> To use llgamma efficiently with giant numbers, you'd have to first
> transform to log(n):
>
> x = log(n)
> f(x) = x + log(x + 1)

ERROR!  That should have been...

f(x) = x + log(x - 1)

...and this...

> octave:1> x=log(6.384)+4356*log(10);
> octave:2> x+log(x+1)
> ans =  1.0041e+04

...should have had x+log(x-1), but the answer was the same.

Best,

Mike

-- 
Michael B. Miller, Ph.D.
Assistant Professor
Division of Epidemiology
and Institute of Human Genetics
University of Minnesota
http://taxa.epi.umn.edu/~mbmiller/



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