[postgis-users] st_box2d

[Mark Cave-Ayland]

JP de Miranda wrote:

> Mark,
> I do believe that box2d returns a polygon with 5 points.
> Here is an example
> My starting polygon
> 
> POLYGON((-81.507568359375 42.7631458668949,-81.4141845703125 
> 43.6023850422415,-81.32080078125 44.441624217588,-79.6893310546875 
> 44.6526402614971,-78.057861328125 44.8636563054061,-77.047119140625 
> 44.3015041922804,-76.036376953125 43.7393520791547,-76.7889404296875 
> 43.0448886007946,-77.54150390625 42.3504251224346,-78.310546875 
> 42.3260577253395,-79.07958984375 42.3016903282445,-80.2935791015625 
> 42.5324180975697,-81.507568359375 42.7631458668949))
> 
> 
> Results of box2d
> 
> POLYGON((-81.507568359375 42.3016891479492,-81.507568359375 
> 44.8636589050293,-76.036376953125 44.8636589050293,-76.036376953125 
> 42.3016891479492,-81.507568359375 42.3016891479492))

I think you will need to give more information about your query. I get 
this result:

postgis=# select 'POLYGON((-81.507568359375 
42.7631458668949,-81.4141845703125 43.6023850422415,-81.32080078125 
44.441624217588,-79.6893310546875 44.6526402614971,-78.057861328125 
44.8636563054061,-77.047119140625 44.3015041922804,-76.036376953125 
43.7393520791547,-76.7889404296875 43.0448886007946,-77.54150390625 
42.3504251224346,-78.310546875 42.3260577253395,-79.07958984375 
42.3016903282445,-80.2935791015625 42.5324180975697,-81.507568359375 
42.7631458668949))'::geometry::box2d;
                                   box2d
--------------------------------------------------------------------------
  BOX(-81.507568359375 42.3016891479492,-76.036376953125 44.8636589050293)
(1 row)


ATB,

Mark.

-- 
Mark Cave-Ayland
Sirius Corporation - The Open Source Experts
http://www.siriusit.co.uk
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