[Proj] epsg parameters

Jean-Claude Repetto jrepetto at free.fr
Wed Apr 2 06:48:01 EDT 2008


Am I wrong, or the epsg parameters file shipped with PROJ V4.6 is not 
up-to-date ?
I have noticed that several +towgs84 parameters are missing. They are in 
the official EPSG database, but not in the /usr/share/proj/epsg file.

Exemple : WGS72
The /usr/share/proj/epsg file contains :
<4322> +proj=longlat +ellps=WGS72 +no_defs  <>

It should be :
<4322> +proj=longlat +ellps=WGS72 +towgs84=0,0,4.5,0,0,0.554,0.219 
+no_defs  <>
(look at <http://proj.maptools.org/gen_parms.html#towgs84>)

I have discovered this problem when using some projections used by 
french islands (Martinique, Guadeloupe).

# Guadeloupe 1948
<4622> +proj=longlat +ellps=intl +no_defs  <>
# Martinique 1938
<4625> +proj=longlat +ellps=intl +no_defs  <>

I think that they should be :

# Guadeloupe 1948
<4622> +proj=longlat +ellps=intl 
+towgs84=-472.29,-5.63,-304.12,0.4362,-0.8374,0.2563,1.8984 +no_defs  <>
# Martinique 1938
<4625> +proj=longlat +ellps=intl 
+towgs84=126.93,547.94,130.41,-2.7867,5.1612,-0.8584,13.8227 +no_defs  <>

But I am sure there are several other parameters missing.
Does anybody know if the proj.4 epsg file has been created manually, or 
has been automatically converted from the EPSG database ?


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