[postgis-users] Polygon covering points?

[Webb Sprague]

Close - here is what worked:

r_gis=# \a
Output format is unaligned.
or_gis=# select
astext(st_convexhull(st_collect_garray(accum(the_geom)))) from
placenames where desig = 'airport';
astext
POLYGON((1067274.25 92457.4140625,281557.9375
139436.3125,252687.421875 267215.4375,233052.859375
428942.28125,455850.8125 1624608.875,2146496.75 1565915.375,2304552
1452654.375,2229047 847370.375,2067352.875 104695.6328125,1067274.25
92457.4140625))

Thanks to everyone.  It seems like the "garray" should be unnecessary
and should be overloaded, but there you go.

-W

On 10/17/07, Mark Leslie <mark.leslie at lisasoft.com> wrote:
> Webb Sprague wrote:
> > On 10/17/07, Anton A. Patrushev <anton at orkney.co.jp> wrote:
> >> Convex hull?
> >
> > I can't find a convex_hull that takes a SET of points.  Pointers?
> >
> > or_gis=# \df *convex*
> >                         List of functions
> >  Schema |     Name      | Result data type | Argument data types
> > --------+---------------+------------------+---------------------
> >  public | convexhull    | geometry         | geometry
> >  public | st_convexhull | geometry         | geometry
> > (2 rows)
> >
> > Thanks though
> > _______________________________________________
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> >
>
> Try, ST_ConvexHull(ST_Collect(geometry set))
>
> --
> Mark Leslie
> Software Architect
> LISAsoft Pty Ltd
> www.lisasoft.com
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