[GRASS-user] datum itrf 92 not recognised

[Markus Neteler]

On Sat, Sep 15, 2012 at 7:51 AM, tigrida <adriana.mata at ipicyt.edu.mx> wrote:
> Hi all!
> I want to create a new location in GRASS GIS using a file that uses the ITRF
> datum 1992 and get the error:
>
> g.proj returned the following informational message:
> WARNING: Datum ITRF_1992 not recognised by GRASS and no parameters found
>
>
> What  can I do?  anyone can help me?

I have downloaded a test dataset from

http://mapserver.inegi.org.mx/data/mgm/?s=geo&c=1298
--> Polígonos de Localidades Urbanas Geoestadísticas de Zonas
Pendientes por Asignar (7.43 Kb)

which reports

ogrinfo -so LOCALIDADES_URBANAS.shp LOCALIDADES_URBANAS
INFO: Open of `LOCALIDADES_URBANAS.shp'
      using driver `ESRI Shapefile' successful.

Layer name: LOCALIDADES_URBANAS
Geometry: Polygon
Feature Count: 7
Extent: (3349667.844974, 487959.061402) - (3928899.605898, 990833.558894)
Layer SRS WKT:
PROJCS["North_America_Lambert_Conformal_Conic",
    GEOGCS["ITRF92",
        DATUM["ITRF_1992",
            SPHEROID["GRS_1980",6378137.0,298.257222101]],
        PRIMEM["Greenwich",0.0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Lambert_Conformal_Conic_2SP"],
    PARAMETER["False_Easting",2500000.0],
    PARAMETER["False_Northing",0.0],
    PARAMETER["Central_Meridian",-102.0],
    PARAMETER["Standard_Parallel_1",17.5],
    PARAMETER["Standard_Parallel_2",29.5],
    PARAMETER["Latitude_Of_Origin",12.0],
    UNIT["Meter",1.0]]
CVE_ENT: String (254.0)
CVE_LOC: String (254.0)
CVE_MUN: String (254.0)
NOM_LOC: String (254.0)

Here I see
http://svn.osgeo.org/gdal/trunk/gdal/data/gdal_datum.csv
-> 1042,Mexican Datum of 1993,geodetic,ITRF1992 at epoch
1988.00.,1993,7019,8901,1160,Geodetic survey.,"Realised by a frame of
15 active GPS stations observed and adjusted in the ITRF1992. Includes
ties to tide gauges. Replaces NAD27 (code 6267).","National
Densifications per http://www.sirgas.org. See also
www.fig.net/pub/cairo/papers/ts_13/ts13_03_hansen.pdf.",OGP,"2010/11/02",2009.087
2010.090,0,

and
https://svn.osgeo.org/gdal/trunk/gdal/data/geoccs.csv
4481,Mexican Datum of 1993,1042,Mexican Datum of
1993,1042,9001,7019,8901,1,0,6500

I found also EPSG code 4481:
http://www.epsg-registry.org/
--> retrieve by code: 4481
   --> Mexican Datum of 1993 to WGS 84 (1)

The values are all 0 (so I suspect that towgs84=0,0,0).

I found also this discussion:
http://forums.esri.com/Thread.asp?c=93&f=984&t=273181

The best is to ask this question (feel free to forward what I wrote
here) at the PROJ4
mailing list where many experts read (I'll follow the disussion there, too):

http://lists.maptools.org/mailman/listinfo/proj

Then we may be able to add the missing definition to GRASS GIS.

Markus