[postgis-users] Concave hull problem & delaunay triangulation - help needed please

[Simon Greener]

Brent,

> I have Simon's code working fine, at least using his example invocation, from:
> http://www.spatialdbadvisor.com/postgis_tips_tricks/290/r-based-delaunay-triangulation-function-for-postgis-using-the-deldir-package
>
> But I can't figure out how to make it work with my point data. I don't know R or PL/R well enough to adapt it.
>
> I have a set of sample points in a table:
>
>  Column |      Type       |                                  --------+-----------------+-----------------
>  id     | integer         | not null default
>  geom   | geometry(Point) |
> Can anyone explain, ideally in words of one syllable or less, how Simon's function from the link above needs to be adapted to read my points >dataset as input?


Just pass in a valid SQL statement that exposes your x y and z point values eg:

SELECT ST_Delaunay_Triangles('select ST_X(p.geom) as x,ST_Y(p.geom) as y,ST_Z(p.geom) from sample_points_in_table p') as triangle;

regards
Simon
-- 
Holder of "2011 Oracle Spatial Excellence Award for Education and Research."
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