Siginificant figures calculating zprob

[Duncan Smith]

"Sarah Wang" <sarah_wang23 at hotmail.com> wrote in message
news:9405c70f.0404031852.155d17d5 at posting.google.com...
> Hello everyone!
>
> I want to calculate zprob(the area under the normal curve)
> with python and I managed to find a function from the
> internet.
>
> But the problem is that the function calculates the result
> with only a few significant figures. If I want to get the
> 20th number of the result(z-prob) what should I do?

Why would you need this degree of precision?

I want
> to get the confidence level of "6sigma" and all I get at the
> moment is "1".
>

How about posting the code?  Check out Gary Strangman's stats.py
http://www.nmr.mgh.harvard.edu/Neural_Systems_Group/gary/python.html

Duncan