[GRASS-dev] Help needed Accessing Grass Modules through python

[Glynn Clements]

Martin Landa wrote:

> > I am working on accessing grass functionalities through python, but I don't
> > know which way I should take to achieve this goal.
> >
> > I have SWIG WIN, GRASS 6.3, Python 2.5, Quantum GIS 0.11
> >
> > I want to call suppose "mapcalc" of grass from inside python.
> >
> > Whether this is possible, If yes then how. Whether it can be achieved
> > through g.parser, SWIG or through any other way.
> 
> I would suggest to use Python scripting library from GRASS >= 6.4 [1].
> See raster.mapcalc().

The existing grass.mapcalc() function won't work in 6.4. That function
shouldn't have been backported from 7.0, as it requires the 7.0
version of r.mapcalc (which uses G_parser()).

It needs something like:

-    if run_command('r.mapcalc', expression = e) != 0:
+    if write_command('r.mapcalc', stdin = e) != 0:

Either that, or use call(['r.mapcalc', expression]).

-- 
Glynn Clements <glynn at gclements.plus.com>