See this thread:

http://groups.google.com/groups?thre...ing.google.com

Particularly the Post by Ian Smith

captured below:

This is known see
http://support.microsoft.com/default...5214#appliesto.

The function cdf_gamma in
http://members.aol.com/iandjmsmith/Examples.xls will evaluate
gammadist accurately.

Ian Smith

--
Regards,
Tom Ogilvy



"Bob" wrote in message
...
I have a visual basic macro which uses Excel's Gammadist
worksheet function. I just discovered that for certain
input values gammadiat returns #num. Does anybody know
of where I can obtain visual basic code which emulates
the gammadist function?