[postgis-users] Retrieve the portion of line external to polygon

[Andrea Peri]

>>I try with the ST_Difference and the ST_Intersections but both seem to
>>work only with geometries of same type.


>ST_Difference should work.
>Do you have a _small_ example showing it doesn't ?

oops sorry,
I need to explain better

The ST_Difference effectively work with two geometry of different type, but
not always retrive the external portion,
the example I post show an example of because this happened.


2011/2/16 strk <strk at keybit.net>

> On Tue, Feb 15, 2011 at 11:16:44PM +0100, aperi2007 wrote:
> > Hi,
> >
> > I need to retrieve the portion of a line external to a polygon,
> > I try with the ST_Difference and the ST_Intersections but both seem to
> > work only with geometries of same type.
>
> ST_Difference should work.
> Do you have a _small_ example showing it doesn't ?
>
> --strk;
>
>  ()   Free GIS & Flash consultant/developer
>  /\   http://strk.keybit.net/services.html
>



-- 
-----------------
Andrea Peri
. . . . . . . . .
qwerty àèìòù
-----------------
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20110216/68962af9/attachment.html>