[postgis-users] Midpoint function?

[Pradeep B V]

On 6/21/07, Rodrigo Martín LÓPEZ GREGORIO <
rodrigomartin at lopezgregorio.com.ar> wrote:
>
> As Nicolas says you should use:
>
> select line_interpolate_point(LineMerge(the_geom),0.5).
>
> you can try this and see if the point is the one you want:


It works fine.

and here is the proof.

select distance(startpoint(the_geom),
line_interpolate_point(LineMerge(the_geom),0.5)) as stdist,
distance(endpoint(the_geom), line_interpolate_point(LineMerge(the_geom),0.5))
as endist from testdataset limit 1;

                    stdist         |       enddist
              ----------------------+----------------------
 0.000737003466840363 | 0.000737003466840363

Thanks Rodrigo/Nicolas.

 - Pradeep B V
www.btis.in
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