[postgis-users] ST_StartPoint() for MultiLineStrings

[Martin Davis]

In which case why not just extend ST_StartPoint to include this 
behaviour?  Always nicer to keep the function list as short as possible.

On 9/27/2012 7:31 AM, David William Bitner wrote:
> Perhaps to match a number of people's expectations, there should be an 
> ST_First Point() that is basically 
> ST_StartPoint(ST_GeometryN(ST_Multi(geometry),1))
>
>
>
> On Tue, Sep 25, 2012 at 4:08 PM, Paul Ramsey <pramsey at opengeo.org 
> <mailto:pramsey at opengeo.org>> wrote:
>
>     When ST_NumGeometries == 1, you can run ST_StartPoint on
>     ST_GeometryN(geom,1). Where ST_NumGeometries > 1 you are in
>     "interpretation land". What's the start point of a geometry with two
>     lines?
>
>     P.
>
>     On Tue, Sep 25, 2012 at 1:38 PM, David Quinn
>     <daithiquinn at gmail.com <mailto:daithiquinn at gmail.com>> wrote:
>     > As ST_StartPoint( multilinestring ) returns NULL for PostGIS 2.0
>     > (http://postgis.refractions.net/docs/ST_StartPoint.html ), what
>     > approach can be used to identify the start and end points of a
>     > multilinestring?
>     >
>     > Thanks,
>     > David
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> David William Bitner
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