[postgis-users] Z and M coordinates seem inconsistent and barely supported

Ben Harper rogojin at gmail.com
Thu Jul 2 22:07:21 PDT 2009


brilliant - thanks.

On Fri, Jul 3, 2009 at 12:04 AM, Paul Ramsey<pramsey at cleverelephant.ca> wrote:
> AsBinary also strips out the higher dimensions in the interests of
> spec compliance (old OGC spec)
>
> select asewkt(geomfromewkb(asewkb('POINT(0 0 0 0)')));
>
>
>
> On Thu, Jul 2, 2009 at 1:31 PM, Ben Harper<rogojin at gmail.com> wrote:
>> Thanks - I see that EWKT works, but is there an equivalent mechanism for WKB?
>>
>> SELECT AsBinary(GeomFromEWKT('POINT(0 0 0 0)'));
>>
>> yield the exact same result as
>>
>> SELECT AsBinary(GeomFromEWKT('POINT(0 0)'));
>>
>>
>>
>> On Thu, Jul 2, 2009 at 5:56 PM, Paul Ramsey<pramsey at cleverelephant.ca> wrote:
>>> select geomfromewkt('POINT(0 0 0 0)');
>>>
>>>
>>> On Thu, Jul 2, 2009 at 8:51 AM, Ben Harper<rogojin at gmail.com> wrote:
>>>> I'm struggling to create a geometry field in PostGIS that stores Z and
>>>> M coordinates. Are these supported?
>>>> Some issues:
>>>> 1. I cannot create a ZM field. "Dimensionality must be 3 or less"
>>>> 2. GeomFromText() doesn't recognize "POINT Z (0 0 0)"
>>>> 3. GeomFromText() does parse (with a warning) "POINTM (0 0 0)", but it
>>>> appears the DB isn't really storing the Z coordinate.
>>>> 4. Using the C library interface, I can't get WKB geometry with Z to parse.
>>>>
>>>> Thanks,
>>>> Ben
>>>> _______________________________________________
>>>> postgis-users mailing list
>>>> postgis-users at postgis.refractions.net
>>>> http://postgis.refractions.net/mailman/listinfo/postgis-users
>>>>
>>> _______________________________________________
>>> postgis-users mailing list
>>> postgis-users at postgis.refractions.net
>>> http://postgis.refractions.net/mailman/listinfo/postgis-users
>>>
>> _______________________________________________
>> postgis-users mailing list
>> postgis-users at postgis.refractions.net
>> http://postgis.refractions.net/mailman/listinfo/postgis-users
>>
> _______________________________________________
> postgis-users mailing list
> postgis-users at postgis.refractions.net
> http://postgis.refractions.net/mailman/listinfo/postgis-users
>



More information about the postgis-users mailing list