[OSGeo Africa] SRID

[Josh Livni]

Just in case you haven't come across it yet, you might find
http://spatialreference.org to be a useful site for both looking up existing
references, and - in cases like this - adding new ones with associated notes
on usage.
Cheers,

 -Josh


On Tue, Feb 17, 2009 at 5:14 AM, Gavin Fleming <GavinF at mintek.co.za> wrote:

> In PostGIS: SELECT * FROM spatial_ref_sys;
>
> The only problem is, for SA projections like the LOs on Hartebeesthoek
> datum, proj4 can't handle a south-facing projection (yet) and be aware
> in PostGIS that while their EPSG codes are defined properly, the
> matching proj4 strings are undefined (at 1.2 at any rate).
>
> I have some LO 27 data in PostGIS that QGIS and uDIG couldn't project,
> yet GeoServer did. For the South African EPSG LO definitions to apply
> though, you have to swap your x and y signs (though not the axes).
>
> A workaround in South Africa is to use normal Transverse Mercator on
> Hartebeesthoek and standardise the axes and signs (i.e. make them look
> conventional like the rest of the world) - then just define your own
> EPSG (and proj4) code and add a record to PostGIS.
>
> Here's an Albers one I use a lot:
>
> srid,auth_name,auth_srid,srtext,proj4text
> 40000,EPSG,40000,PROJCS["South Africa Albers Equal Area
> 24",GEOGCS["GCS_Hartebeesthoek_1994",DATUM["D_Hartebeesthoek_1994",SPHER
> OID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["D
> egree",0.0174532925199433]],PROJECTION["Albers"],PARAMETER["False_Eastin
> g",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",24.
> 0],PARAMETER["Standard_Parallel_1",-18.0],PARAMETER["Standard_Parallel_2
> ",-32.0],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]],+proj=ae
> a +lat_1=-18 +lat_2=-32 +lat_0=0 +lon_0=24 +x_0=0 +y_0=0 +ellps=WGS84
> +units=m +no_defs
>
> Gavin
>
>
>
> -----Original Message-----
> From: africa-bounces at lists.osgeo.org
> [mailto:africa-bounces at lists.osgeo.org] On Behalf Of Tim Sutton
> Sent: 17 February 2009 13:57 PM
> To: Africa local chapter discussions
> Subject: Re: [OSGeo Africa] SRID
>
> Hi
>
>
> On Tue, Feb 17, 2009 at 12:10 PM,  <bartvde at osgis.nl> wrote:
> > Hi,
> >
> > SRID is an Oracle term so I assume you are talking about Oracle
> Spatial.
> >
> > It's in a table called CS_SRS in the MDSYS schema:
> >
> > select * from MDSYS.CS_SRS
> >
> > Best regards,
> > Bart
> >
> >> Hi All,
> >>
> >> First posting!!!
> >>
> >> Where can I get a list of SRID's.
> >>
> >> Regards,
> >>
> >> Clinton Papenfus
> >> 0833767083
>
>
>
> For a user friendly list of CRS's you can also click on the icon in
> the bottom right corner of the QGIS window, and you will be presented
> with a CRS list. Click on any CRS entry to see its proj4 definition.
>
> Regards
>
> Tim
>
> --
> Tim Sutton - QGIS Project Steering Committee Member (Release  Manager)
> ==============================================
> Visit http://linfiniti.com to find out about:
>  * QGIS programming services
>  * Mapserver and PostGIS based hosting plans
>  * FOSS Consulting Services
> Skype: timlinux Irc: timlinux on #qgis at freenode.net
> ==============================================
> _______________________________________________
> Africa mailing list
> Africa at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/africa
>
> This message is intended for the addressee only.
> Information and attachments in this e-mail may contain confidential,
> proprietary, or legally privileged information.
> If you are not the intended recipient, or responsible for delivery of the
> message to the intended recipient,
> any disclosure, copying, distribution, or any action taken is prohibited
> and may be unlawful,
> and could result in a claim against you.
>
> _______________________________________________
> Africa mailing list
> Africa at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/africa
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/africa/attachments/20090217/2a635cf7/attachment-0001.html