Grass GIS and Python Error

Question

I am trying to use Python with Grass GIS. To get started I try to read in a raster TIFF.

The import of grass.script works fine:

import grass.script as g

But if I am trying to run a command I get the following error

sloperaster = 'slopet.tif'
a = g.run_command('r.in.gdal',
 input = sloperaster,
 output = 'test')
>>>'r.in.gdal' is not recognized as an internal or external command,
operable program or batch file.

Any ideas what is causing that and how to resolve it?

I am on Windows 7 (64bit), Python 2.7.5 (32bit), Grass GIS 6.4.3 (32bit)

Answer 1

There are three ways to use Python with GRASS GIS:

1) from the Python shell of the GRASS GIS Layer Manager:

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• you don't need to import any GRASS Python module

2) from the Python shell in the GRASS shell

enter image description here

• you only need to import the grass.script module

3) from outside

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For that,

• some environment variables have to be set before using Python, see "Creating Python scripts that call GRASS functionality from outside" in GRASS and Python
• some GRASS variables have to be set in Python (GISBASE, gisdb, location, mapset)

• ustroetz: I use option 3. I did set the environment variables. Also I think in the right way otherwise I wouldn't be able to import grass.script. But I didn't set any GRASS variables. Maybe that's why it doesn't work. I look into that. Thanks.