> On Dec 8, 2022, at 1:53 PM, Paul Ramsey <pramsey@cleverelephant.ca> wrote:
>
> Just a utility function to generate random numbers from a normal
> distribution. I find myself doing this several times a year, and I am
> sure I must not be the only one.
Thanks for the patch. What do you think about these results?
+-- The semantics of a negative stddev are not well defined
+SELECT random_normal(mean := 0, stddev := -1);
+ random_normal
+---------------------
+ -1.0285744583010896
+(1 row)
+
+SELECT random_normal(mean := 0, stddev := '-Inf');
+ random_normal
+---------------
+ Infinity
+(1 row)
+
+-- This result may be defensible...
+SELECT random_normal(mean := '-Inf', stddev := 'Inf');
+ random_normal
+---------------
+ -Infinity
+(1 row)
+
+-- but if so, why is this NaN?
+SELECT random_normal(mean := 'Inf', stddev := 'Inf');
+ random_normal
+---------------
+ NaN
+(1 row)
+
—
Mark Dilger
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
