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PyQGIS scripts are great to automate spatial processing workflows. It’s easy to run these scripts inside QGIS but it can be even more convenient to run PyQGIS scripts without even having to launch QGIS. To create a so-called “stand-alone” PyQGIS script, there are a few things that need to be taken care of. The following steps show how to set up PyCharm for stand-alone PyQGIS development on Windows10 with OSGeo4W.

An essential first step is to ensure that all environment variables are set correctly. The most reliable approach is to go to C:\OSGeo4W64\bin (or wherever OSGeo4W is installed on your machine), make a copy of qgis-dev-g7.bat (or any other QGIS version that you have installed) and rename it to pycharm.bat:

Instead of launching QGIS, we want that pycharm.bat launches PyCharm. Therefore, we edit the final line in the .bat file to start pycharm64.exe:

In PyCharm itself, the main task to finish our setup is configuring the project interpreter:

First, we add a new “system interpreter” for Python 3.7 using the corresponding OSGeo4W Python installation.

To finish the interpreter config, we need to add two additional paths pointing to QGIS\python and QGIS\python\plugins:

That’s it! Now we can start developing our stand-alone PyQGIS script.

The following example shows the necessary steps, particularly:

  1. Initializing QGIS
  2. Initializing Processing
  3. Running a Processing algorithm
import sys

from qgis.core import QgsApplication, QgsProcessingFeedback
from qgis.analysis import QgsNativeAlgorithms

QgsApplication.setPrefixPath(r'C:\OSGeo4W64\apps\qgis-dev', True)
qgs = QgsApplication([], False)
qgs.initQgis()

# Add the path to processing so we can import it next
sys.path.append(r'C:\OSGeo4W64\apps\qgis-dev\python\plugins')
# Imports usually should be at the top of a script but this unconventional 
# order is necessary here because QGIS has to be initialized first
import processing
from processing.core.Processing import Processing

Processing.initialize()
QgsApplication.processingRegistry().addProvider(QgsNativeAlgorithms())
feedback = QgsProcessingFeedback()

rivers = r'D:\Documents\Geodata\NaturalEarthData\Natural_Earth_quick_start\10m_physical\ne_10m_rivers_lake_centerlines.shp'
output = r'D:\Documents\Geodata\temp\danube3.shp'
expression = "name LIKE '%Danube%'"

danube = processing.run(
    'native:extractbyexpression',
    {'INPUT': rivers, 'EXPRESSION': expression, 'OUTPUT': output},
    feedback=feedback
    )['OUTPUT']

print(danube)

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Update 2017: Please follow the instructions on the OSGeo4W website: https://trac.osgeo.org/osgeo4w/wiki/ExternalPythonPackages


Update 2015: I now recommend this workflow based on Nathan’s post on installing Python setup tools:

  1. Download ez_setup.py
  2. Run python ez_setup.py in your OSGeo4W shell
  3. Run easy_install pysal in your OSGeo4W shell

Original post:

Today’s post is a summary of how to install PySAL on Windows for OSGeo4W Python.

The most important resource was https://trac.osgeo.org/osgeo4w/wiki/ExternalPythonPackages

In the OSGeo4W Shell run:

C:\Users\anita_000\Desktop>curl http://python-distribute.org/distribute_setup.py | python

Update: Note that python-distribute.org has gone down since I posted this. See http://www.gossamer-threads.com/lists/python/python/1158958 for more info.

Then download https://raw.githubusercontent.com/pypa/pip/master/contrib/get-pip.py to the Desktop and run:

C:\Users\anita_000\Desktop>python get-pip.py

When pip is ready, install PySAL:

C:\Users\anita_000\Desktop>pip install pysal

Test the installation:

C:\Users\anita_000\Desktop>python
Python 2.7.5 (default, May 15 2013, 22:44:16) [MSC v.1500 64 bit (AMD64)] on win 32
Type "help", "copyright", "credits" or "license" for more information.
>>> import pysal
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