Re: postgres 9.2.2 point conversion from polygon doesn't always give accurate center - Mailing list pgsql-bugs

On 1 February 2013 17:54, Colin Dunklau <colin.dunklau@gmail.com> wrote:

> For the below two queries, I expect to get a result of (0.5, 0.5).
>
> cdunklau=# select point( polygon '((0,0),(0,1),(1,1),(0,1))');
>     point
> -------------
>  (0.25,0.75)
> (1 row)
>

I think you just simply mistyped the coordinates...

sriggs=# select point( polygon '((0,0),(0,1),(1,1),(1,0))');
   point
-----------
 (0.5,0.5)
(1 row)

Your last point is a duplicate of the 2nd point, so you have a
4-pointed triangle and hence a strange centre.

--
 Simon Riggs                   http://www.2ndQuadrant.com/
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