[GRASSLIST:6742] Re: PPOJ help required

[Frank Warmerdam]

On 5/9/05, Ferencik Ioan <ferencik.ioan at personal.ro> wrote:
> 
> 
> I am a new user of GRASS GIS and I have some diffieculties with PROJ. I want to
> project a file with  lat/long coordinates to a stereographic projection (epsg
> code is 31700). Can someone give me a hint how could I do this? i mean to tpe at
> stdin
>  the coordinates in DMS foromat and to get them back from proj iin STEREO 70
> projection
> 
> i think that it shoul be something like
> proj +proj=stere +ellps=krass
> +towgs84=-27.0,+135.0,+84.5,0.0,0.0,-0.554,-0.2263 x_0=500000 y_0=500000
> lat_0=46 lon_0=25 lat_ts=46 k_0=0.99975 +units=m -r <<EOF

Ferencik,

If you are using the "proj" comand, you need a "+" in front
of each argument.  Note that the towgs84 is ignored by the
proj command which implicitly converts between latlong and
projected coordinates on the same datum. 

So, something a bit more like:

proj +proj=stere +lat_0=46 +lon_0=25 +k=0.999750 +x_0=500000
+y_0=500000 +ellps=krass +units=m +no_defs -r << EOF

Keep in mind that DMS format looks like this in PROJ:

 20d15'7.5"

And with the -r flag you have requested input to be in lat, then long
format, rather than long then lat (as it typical in PROJ.4).  Your email
didn't actually indicate whether things were working for you or not.
It is often helpful to explain what problem you have encountered as
well as your general objective. 

Best regards,


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