[GRASS-user] (no subject)

[Markus Neteler]

Hamish wrote on 05/03/2007 02:45 AM:
>> ich benötige hilfe bei folgendem problem. meine location verläuft über
>> zwei meridiane (9E und 12E). die karten, die ich benötige, liegen alle
>> bis auf eine, die in 12E liegt, in 9E (in der location als central
>> median angegeben). diese karte liegt nach dem importieren viel zu weit
>> östlich. wie muss ich die location aufbauen, damit die karte richtig
>> dargestellt wird?
>>     
Since you write in German, I guess that you are talking about
Gauss-Krueger here.
You have to create two locations (because each stripe has its
own projection). Then you can reproject (r.proj) the map
of one location into the other, but that can introduce a
positional error. In general it would be better to use another
projection which covers both areas such as LAEA or LCC.
There are official LAEA and LCC definitions for Europe:

http://crs.bkg.bund.de/crseu/crs/eu-description.php

To easily generate this:
#LCC: Within a GRASS location (needs >= GRASS 6.2.x):
  g.proj -c proj4='+init=epsg:3034' location=eu_lcc

#LAEA: Within a GRASS location (needs >= GRASS 6.2.x):
  g.proj -c proj4='+init=epsg:3035' location=eu_laea


Depending on your needs one of these commands might be of use for you.

Markus

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ITC -> dall'1 marzo 2007 Fondazione Bruno Kessler
ITC -> since 1 March 2007 Fondazione Bruno Kessler
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