[Proj] PROJ 4.4.8 - Release Candidate

Markus Neteler neteler at itc.it
Wed May 5 08:40:40 EDT 2004


On Tue, May 04, 2004 at 02:25:50PM -0400, Frank Warmerdam wrote:
> Markus Neteler wrote:
> >Frank,
> >
> >thanks for the updates. However, the problem with prime meridian
> >seems to be unsolved.
> >
> ># LatLong to Italian Gauss Boaga Fuso Ovest (1st Zone):
> >cs2cs -v +proj=latlong +datum=WGS84 +to +init=epsg:26591 \
> >         +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68
> >11d12'26E 46d06'17N 100
> >-251428.83      5362296.50 54.97
> >
> > -> This result is wrong.
> >
> ># Using the old method:
> >cs2cs -v +proj=latlong +datum=WGS84 +to +proj=tmerc +lat_0=0 +lon_0=9 \
> >       +k=0.999600 +x_0=1500000 +y_0=0 +ellps=intl +units=m \
> >       +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68 \
> >       +no_defs
> >11d12'26E 46d06'17N 100
> >1670617.27      5108072.04 54.97
> >
> > -> This looks correct.
> >
> >In my opinion the nad/epsg file entries for 26591 and 26592
> >and maybe all others with +pm parameter are wrong (more than
> >60 projections). Or the prime meridian is not applied correctly.
> >
> >Interesting: The lon_0 values seem to be correct in GDAL/gcs.csv
> >
> >Probably I am missing something (please let me know),
> 
> Markus,
> 
> Now I remember why I put off dealing with this for so long.  There was
> a tangle of problems and mistaken assumptions in the way I was processing
> various longitudinal values relative to prime meridians through from the
> EPSG to the PROJ.4.  I have corrected the code in GDAL/OGR used to generate
> the epsg file, and issued a new PROJ 4.4.8 release with the corrected
> epsg file.  The first example you gave now gives correct results.
> 
> Please verify as soon as you get a change.

Frank,

it was a good idea to insist :-) Finally it looks reasonable:

cs2cs -v +proj=latlong +datum=WGS84 +to +init=epsg:26591 \
         +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68
# ---- From Coordinate System ----
#Lat/long (Geodetic)
#
# +proj=latlong +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0
# ---- To Coordinate System ----
#Transverse Mercator
#       Cyl, Sph&Ell
# +init=epsg:26591 +towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68
# +proj=tmerc +lat_0=0 +lon_0=-3.45233333333333 +k=0.999600 +x_0=1500000
# +y_0=0 +ellps=intl +pm=rome +units=m +no_defs
11d12'26E 46d06'17N 100
1670617.27      5108072.04 54.97

Will you update the source package on the web site and the RPM?

Now let's hope that the vendors pick up the package quickly.
I have just created one for Mandrake 9.2 (so we could point the 
GRASS users to the site).

Best regards

 Markus Neteler




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