[GRASS-user] new location epsg GUI vs command line

Francesco Mirabella mirabell at unipg.it
Tue Aug 28 08:42:18 EDT 2007


Dear all,
I've been struggling with this for some hours, maybe it's my fault or it
has been overcome already, anyway:

In grass 6.3cvs
I've created a Latlong location with rome40 datum, international ellps.
The location was created by using the GUI "create from epsg".
The location looks fine, and the "d.where" output of points is reasonable, however, when projecting the data on a UTM location (zone 33 for example) I got the longitude in millions (should be hundreds).

To be short, I have tested that in this way the "g.proj -p" gives:
#######################################################
GRASS 6.3.cvs (LatLong_rome40):~ > g.proj -p
-PROJ_INFO-------------------------------------------------
name       : Lat/Lon
proj       : ll
datum      : rome40
ellps      : international
pm         : rome
no_defs    : defined
towgs84    : -104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68
-PROJ_UNITS------------------------------------------------
unit       : degree
units      : degrees
meters     : 1.0
GRASS 6.3.cvs (LatLong_rome40):~ >
#########################################################

Note that it gives "pm=rome"

If I create the location with the "Projection values" option the
"g.proj -p" output looks slightly different and without the pm=rome:
########################################################
GRASS 6.3.cvs (prova_latlong):~ > g.proj -p
-PROJ_INFO------------------------------------------------- name       :
Latitude-Longitude datum      : rome40
towgs84    : -104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68
proj       : ll
ellps      : international
-PROJ_UNITS------------------------------------------------
unit       : degree
units      : degrees
meters     : 1.0
GRASS 6.3.cvs (prova_latlong):~ >
#########################################################


When I re-project data from this latter location in the UTM location I
get the right numbers.

I hope this might help,

Francesco





More information about the grass-user mailing list