[GIS] How to enable GRASS-modules in QGIS

configurationgrassqgisqgis-pluginstools

I have the latest QuantumGIS-1.9.0-master from Github with python-modules support and full GRASS-integration (GRASS-4.6.3-RC2) on Linux.

When opening the GRASS-tools plugin, it only displays six tools. But there are more like 300 installed.

Only six tools available?

The QGIS-Wiki tells me to add new tools to the GRASS toolbox menu using some xml file in:

qgis/src/plugins/grass/config/default.qgc

But where to find this file and how to update it? Isn't the src-directory only used prior compiling QGIS?

And why are my GRASS modules not included in QGIS by default?

Update 1: Ok, at least I found the file:

~ $ find / -name default.qgc 2> /dev/null
/usr/local/share/qgis/grass/config/default.qgc

But the contents look good. How to trigger QGIS to load the tools? What's the point I'm missing here?

Update 2: Okay, using Sextante-plugin seems the way to go. But this is pretty much broken. I keep getting Error-Messages like this one. I tried reinstalling, but this didn't solve it.

Sextante: broken all over.

Best Answer

First, full installation of OSGeo4W: http://trac.osgeo.org/osgeo4w/ Use the binary package(#1 under step 2).

Second, fetch the Sextante plugin for QGIS, and add it.

You should now be able to access the GRASS modules(I have currently 154 geoalgorithms).

Source: I used this over the weekend to perform various raster analysis operations, most of which using GRASS-specific tools, all done within QGIS.

Hope this helps.

Related Solutions

[GIS] Calling GRASS modules in pyQGIS

To use grass functions from a plugin or from the console, you must first import the grass module like this:

import grass.script as grass

Forgetting the import will cause the NameError for grass.

Follow detailed instructions on using grass from within python

If you are running on windows and you get a Bad Handle error when you try to import grass, this is a result of an unresolved python bug that occurs on some window systems. To work around the problem, put the code that imports and calls grass in a separate script. Then, run this script as an independent process from within your plugin.

callgrass.py:

if __name__ == '__main__':

import grass.script as grass
grass.run_command("v.to.db", map='bl@PERMANENT', layer='2', option='start', units='meters', columns='X,Y,Z')

print "Grass OUtput"

From Console/Plugin:

import subprocess

p1=subprocess.Popen(['callgrass.py', 'arg1', ...], stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
p1.stdin.close()
ret= p1.communicate()[1] # grab grass output  
print ret

Good Luck!

QGIS Installation – How to Install QGIS with Plugins and GRASS Integration from Source

How to compile latest QuantumGIS on a non-Debian/Ubuntu Linux-system with Python-plugin-support and GRASS-integration? I finally did it!

Download and prepare dependencies. Most of them I could find in repositories, sometimes package names vary. Dependencies from INSTALL read-me file:

CMake >= 2.6.2
Flex
Bison >= 2.4
Qt >= 4.4.0
Proj >= 4.4.x
GEOS >= 3.0
Sqlite3 >= 3.0.0
GDAL/OGR >= 1.4.x
Qwt >= 5.0
GRASS >= 6.0.0
Python >= 2.5
SIP >= 4.8, PyQt >= must match Qt version, Qscintilla2

In Sabayon 10, I installed the following packages from repositories:

# equo install cmake gcc geos gdal openstreetmap-icons doxygen graphviz fcgi gsl openscenegraph qwt-5.2.1 pyqwt proj pkg-config txt2tags postgresql-base gnome-pty-helper qscintilla lapack-atlas blas-atlas wxpython shapelib gpsbabel qwtpolar

I did not manage to integrate the prebuild GRASS-6.4.1 from repositories, some libraries were missing. In addition libspatialindex and libspatialite are not available in the repositories. I had to download all three packages and install them manually:

I downloaded libspatialindex version 1.8.0 from here, compiled and installed it:

# cmake . && make && make install
I downloaded libspatialite version 4.0.0 from here, compiled and installed it:

# ./configure --disable-freexl --disable-geosadvanced && make && make install
I downloaded GRASS GIS version 6.4.3-rc2 from here, compiled and installed it:

# ./configure --enable-64bit --enable-shared --with-cxx --with-postgres --with-sqlite --with-gdal --with-python --with-wxwidgets --with-geos --with-x --enable-largefile && make && make install

Get latest source code of Quantum GIS from the official qgis site: qgis-1.8.0.tar.bz. I used the latest snapshot from github as I prefer most recent versions (currently it's the 1.9.0-master-branch).

unpack the source code
create a build directory inside the source code direcoty: $ mkdir build && cd build
Now, you tell cmake where your GRASS libs are, as explained here [via]. Note, the two dots at the end are required. Play with ls to find the libs:

# cmake -DGRASS_PREFIX=/usr/local/grass-6.4.3RC2 -DGRASS_INCLUDE_DIR=/usr/local/grass-6.4.3RC2/include ..
If no errors occur, compile and install QuantumGIS:

# make && make install
One last minor fix, due to this bug:

# cd /etc/ld.so.conf.d/

# echo '/usr/local/lib/qgis/' > qgis.conf

# ldconfig

That's it! :)

QGIS-1.9.0-Master with Python plugins and GRASS integration.

More resources:

Best Answer

Related Solutions

[GIS] Calling GRASS modules in pyQGIS

QGIS Installation – How to Install QGIS with Plugins and GRASS Integration from Source

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