On Sat, Jan 21, 2006 at 12:00:49AM +0100, SunWuKung wrote:
> Does somebody have/know of a function for pg returning the standard
> normal cumulative distribution for a Z score?
Are you looking for something like this?
test=> SELECT z, cdf_ugaussian_p(z) FROM generate_series(-3, 3) AS g(z);
z | cdf_ugaussian_p
----+---------------------
-3 | 0.00134989803163009
-2 | 0.0227501319481792
-1 | 0.158655253931457
0 | 0.5
1 | 0.841344746068543
2 | 0.977249868051821
3 | 0.99865010196837
(7 rows)
cdf_ugaussian_p() is just a little wrapper I put around the GNU
Scientific Library's gsl_cdf_ugaussian_P() function. I can post
an example of how to do that if it's what you're looking for.
--
Michael Fuhr
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