Workshop QGIS Python GeoPython 2017
- Workshop about QGIS and Python - Easy Programming QGIS with Python for Expression Functions
- by Prof. Stefan Keller and Simran Khare, Geometa Lab at HSR Rapperswil
- May 8, 2017, 16:00 - 18:00, Muttenz/Basel, https://2017.geopython.net/#schedule
Expressions in QGIS are very powerful and are used in many core features including selection, calculating field values and styling. QGIS also supports user-defined expressions and functions written in the popular Python programming language. These functions can be used within the expression engine and function editor. This gives users the capability to easily automate their tasks.
This short workshop will give the audience an overview of Python programming in QGIS (PyQGIS), before diving into writing custom Python functions and using them in expressions to perform various tasks to calculate field values. These calculations can be based on different input sources like properties from the same layer, from features of other layers or even by accessing webservices.
In conclusion, it will be discussed how these programming skills can be used for the QGIS processing framework and for implementing plugins in QGIS Version 2 and 3.
- 16:00-16:15 Welcome and QGIS installation (Stefan)
- 16:15-16:30 Intro to QGIS (Stefan)
- 16:30-17:00 Intro to PyQGIS and Expression Functions (EFns) (Stefan)
- 17:00-17:45 Custom EFns with Hands-on Exercises (Simran & Stefan)
- 17:45-18:00 Wrapup & Outlook (Stefan)
- Download everything: GeoPython_2017_Workshop_QGIS_Python.zip (3 MB)
- (This website: http://bit.ly/GeoPython17-QGIS-WS)
- Simran's Github repo: https://github.com/simran001/GeoPython-Workshop where most EFns. went into Nathan's Expressions Plus QGIS plugin
- Nathan Woodrow's nice QGIS plugin "Expressions Plus": https://github.com/NathanW2/qgsexpressionsplus
- Some additional info: https://etherpad.coredump.ch/p/Python-Workshop
Hardware and Software
Hardware: Bring your own device!
- You need a usual computer (Windows, Linux, Mac) with admin credentials (in case of QGIS is not yet installed)
- QGIS: We need current QGIS Version 2.18.x. In case of problems install QGIS LTR Version 2.14.6. Prefer Standalone-Installer over others. No Plugins needed; in they can be loaded later on if needed.