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What are some resources for learning PyQGIS?

It would be interesting having a collection of books or websites that provide some practical examples for learning the syntax or accomplishing specific tasks.

Ideally, these resources should give a general guidance for both beginner and experienced users.

Seeking QGIS user interface tutorials and web resources is a very similar question, but it gives help for learning the QGIS user interface rather than PyQGIS.

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The following resources give a general guidance for learning or using PyQGIS and generally assume a minimum proficiency of working with Python.


QGIS 3.x versions

  • PyQGIS 3 API Documentation: official documentation of the Python API. Documentation for each major release since v3.0 as well as the nightly version is provided;

  • PyQGIS Developer Cookbook: written for QGIS 2.x it is gradually updated to 3.x. It still may be helpful as a tutorial and a reference guide and gives a good overview of the principal functionalities.


QGIS 2.x versions

PyQGIS Documentation:

  • PyQGIS Developer Cookbook: official introduction to PyQGIS programming. It is intended to work both as a tutorial and a reference guide and gives a good overview of the principal functionalities;

  • PyQGIS API Documentation: inofficial documentation of the Python API by SourcePole. It provides a searchable interface, but was not updated since QGIS 2.8;

  • QGIS C++ API Documentation: official C++ API documentation. While describing the C++ API, it can be useful for pyqgis development.

Online books:

Tutorials / Blogs / Web resources:

  • [Anita Graser]: PyQGIS 101: Introduction to QGIS Python programming for non-programmers (tutorial for beginners)

  • Nathan Woodrow: a blog mostly about QGIS stuff that also treats specific topics about the using of PyQGIS. The author is one of the most active QGIS developers;

  • nyalldawson.net: a blog with several posts about the using of PyQGIS. The author is one of the most active QGIS developers;

  • "How To" in QGIS: the site provides some suggestions for solving problems using PyQGIS. When possible, these tips are offered through simple code samples. I'm the author of this blog;

  • QGIS Tutorials and Tips: a section of this blog provides a series of tutorials for learning PyQGIS scripting. The author is a very experienced GIS specialist;

  • Lutra Consulting: a list of posts, having the PyQGIS tag, that cover some topics about PyQGIS.

  • YouTube channel PyQGIS (dozens of videotutorials about using Python with QGIS - in german only, but the principles should become clear);


The following documentation resources should ease your PyQGIS development experience:

A diagram of the main PyQGIS relationships (by Thomas Gratier): https://raw.githubusercontent.com/webgeodatavore/qgis-class-diagram/master/diagramme_principal.png

Searchable documentation of PyQGIS classes (by SourcePole): http://geoapis.sourcepole.com

For example, the addFeature method you had problems with is described here: http://geoapis.sourcepole.com/qgispyapi/qgsvectorlayer#QgsVectorLayer.addFeature

enter image description here

As a second example, the setAttribute method is described here: http://geoapis.sourcepole.com/qgispyapi/qgsfeature#QgsFeature.setAttribute

enter image description here


Not sure what you mean in Getting into Python API of QGIS?, but there is an addFeatures() function of course. This works in QGIS 2.4:

mem_layer = QgsVectorLayer("Polygon?crs=epsg:4326&field=MYNUM:integer&field=MYTXT:string", "temp_layer", "memory")

if not mem_layer.isValid(): raise Exception("Failed to create memory layer")

mem_layer_provider = mem_layer.dataProvider()

my_polygon = QgsFeature()
my_polygon.setGeometry(QgsGeometry.fromRect(QgsRectangle(16,48,17,49)))
my_polygon.setAttributes([10,"hello world"])

mem_layer_provider.addFeatures([my_polygon])

mem_layer.updateExtents()
QgsMapLayerRegistry.instance().addMapLayer(mem_layer)

If you are unhappy with the API docs and the PyQGIS Cookbook, your last chance is to look into working plugins - they are open source after all - and you can easily see if they work in 2.4 ...

To improve documentation, the project happily accepts resources of any kind.


Another collection for informations about learning PyQGIS:
http://spatialgalaxy.net/2014/10/18/pyqgis-resources/


Here are some urls that might help you:

  1. PyQGIS Developer Cookbook https://docs.qgis.org/3.10/en/docs/pyqgis_developer_cookbook/
  2. QGIS Python API documentation https://qgis.org/pyqgis/3.14/
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