On 1 February 2013 17:54, Colin Dunklau <colin(dot)dunklau(at)gmail(dot)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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