[GRASS-user] Get current location projection in a Python Script

[Michael Barton]

On May 25, 2010, at 11:14 AM, Nikos Alexandris wrote:

> Kim Besson:
>>>>> I'm building a GRASS Python Script to automatically import a set of
>>>>> data to my location. At GRASS book (chapter 3.3.3) it uses g.proj -wf
>>>>> to to check current location projection. Can I use the same command in
>>>>> Python to retrieve the same?
> 
>>>>> And how about calling gdalwarp in a Python-GRASS Script? can it be
>>>>> called and used by a Python_GRASS Script? if so, is there any Python
>>>>> example with that?
>>>>> 
>>>>> Regarding "g.proj -wf" command. I get a lot of information. I suppose
>>>>> GDALWARP can read this right ? If not, How can I obtain current
>>>>> Location EPSG code? 
> 
> Michael Barton:
>>>> Use the region() command from the GRASS Python library.
>>>> <http://download.osgeo.org/grass/grass6_progman/pythonlib.html>
> 
> Nikos Alexandris:
>>> Just for the records, a thread not _directly_ about it but close
>>> (enough?):
>>> <http://osgeo-org.1803224.n2.nabble.com/Getting-rows-cols-of-a-region-in
>>> -a- script-tc2787474.html#a2788062>
> 
>> The thread is for BASH and does not work for Python.
> 
> Michael, the thread started for bash but in the last posts (in it) python 
> stuff are demonstrated ( I recall so). Maybe I've posted directly a post where 
> no "python" is included? Hmm... let me see... ... ok, here it is:
> 
> 1. http://www.mail-archive.com/grass-user@lists.osgeo.org/msg08280.html
> 2. http://www.mail-archive.com/grass-user@lists.osgeo.org/msg08288.html
> 
> Maybe they are outdated though (?)
> 
> Cheers, Nikos

These work, but there is a better shortcut now from the GRASS Python library. 


regiondict = grass.region() 

will create a Python dictionary regiondict with values for extents and resolution. It's the same as creating a dictionary by parsing g.region -ugp

Michael