[postgis-users] Point inside a polygon

[Rémi Cura]

Hmm your problem is not about a function, is about using invalid geometries
!

Why simply don't fix your geometry?
you must do it anyway if you want to use PostGIS
without strange bugs.

Use http://postgis.refractions.net/docs/ST_MakeValid.html

Cheers,
Rémi-C


2014-05-03 15:51 GMT+02:00 Larry Reeder <lnreeder at gmail.com>:

> Another thing to be aware of with ST_PointOnSurface is it can return a
> point that's on the boundary of polygon, but *not inside* the polygon, so
> that ST_Within(St_PointOnSurface(surface), surface) returns false.  That's
> bitten me before, but may be OK for your purposes.
>
>        -Larry
>
>
>
>
> On Fri, May 2, 2014 at 1:38 PM, Åsmund Tokheim <asmundto at gmail.com> wrote:
>
>> Hi
>>
>> You can use st_closestpoint(geom, st_centroid(geom)) to make sure that
>> the returned point is in most circumstances at or near the centroid, and
>> always at least on the boundary of the polygon. While st_pointonsurface
>> certainly will be faster, it will often choose a more random point on the
>> surface.
>>
>> Åsmund
>>
>>
>> On Fri, May 2, 2014 at 12:45 PM, Nicolas Ribot <nicolas.ribot at gmail.com>wrote:
>>
>>> Hi,
>>>
>>> Use st_pointOnSurface (
>>> http://postgis.net/docs/manual-2.1/ST_PointOnSurface.html)
>>>
>>> Nicolas
>>>
>>>
>>> On 2 May 2014 06:32, J.Alejandro Martinez Linares <
>>> islanis at infomed.sld.cu> wrote:
>>>
>>>> Hi people, i need your help, i was using st_centroid to get a point
>>>> that be inside a polygon butr st_centroid got a property  that is a problem
>>>> to me, it returns a point that not always is inside the polygon, cause when
>>>> the polygon has an irregular form, the point that st_centroid is outside
>>>> the polygon, and i need a function that do a similar thing that st_centroid
>>>> but i need that the point it returns always be inside the polygon, is there
>>>> a function that do that?
>>>>
>>>> cheers.
>>>>
>>>> --
>>>>
>>>> Este mensaje le ha llegado mediante el servicio de correo electronico
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>>>> establecidas
>>>>
>>>> Infomed: http://www.sld.cu/
>>>>
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