[postgis-users] Another few questions

[Paul Tomblin]

Bruce Rindahl wrote:
>> 3. Is there any way to get the corners of a polygon or its bounding box out
>> as 
>> separate points?
> 
> 
> See the documentation on xmin, xmax, ymin, ymax

What documentation?  In http://postgis.refractions.net/docs/ch06.html, all I 
can find is "ST_xmin(box3d)".  But experimentation shows I can call 'xmin()' 
with a geometry, and 'st_xmin()' doesn't exist.

This is what I find so frustrating about the PostGIS documentation.  There are 
all these functions documented as "ST_*" but it turns out that in order to use 
some of them, you actually have to leave off the "ST_" part.  This function is 
defined as requiring a box3d, but nothing I can find in the docs actually 
comes out and says that if you have a method that takes a box3d, you can call 
it with a geometry and it will use the bounding box (ok, it does come out and 
say that for the && operator, but it doesn't say it's true in general).

I'm really trying to read the manual before asking dumb questions, but the 
manual is horrible.

-- 
Paul Tomblin <ptomblin at xcski.com> http://blog.xcski.com/
"I find your lack of clue...disturbing" - SithAdmin Vader.