Book Image

QGIS Python Programming Cookbook, Second Edition - Second Edition

By : Joel Lawhead
Book Image

QGIS Python Programming Cookbook, Second Edition - Second Edition

By: Joel Lawhead

Overview of this book

QGIS is a desktop geographic information system that facilitates data viewing, editing, and analysis. Paired with the most efficient scripting language—Python, we can write effective scripts that extend the core functionality of QGIS. Based on version QGIS 2.18, this book will teach you how to write Python code that works with spatial data to automate geoprocessing tasks in QGIS. It will cover topics such as querying and editing vector data and using raster data. You will also learn to create, edit, and optimize a vector layer for faster queries, reproject a vector layer, reduce the number of vertices in a vector layer without losing critical data, and convert a raster to a vector. Following this, you will work through recipes that will help you compose static maps, create heavily customized maps, and add specialized labels and annotations. As well as this, we’ll also share a few tips and tricks based on different aspects of QGIS.
Table of Contents (16 chapters)
QGIS Python Programming Cookbook - Second Edition
About the Author
About the Reviewer
Customer Feedback

Creating a DEM from LIDAR

Recent versions of QGIS include the ability to integrate a package named LAStools, which processes Light Detection and Ranging (LIDAR) data. LIDAR data is stored as a point cloud in the LAS format which stores x, y, z laser returns; however, this format isn't good for most GIS map visualizations. In this recipe, we'll convert a LAS point cloud file to a Digital Elevation Model (DEM) in GeoTIFF format used in other examples throughout this book. The DEM can then be used as a raster layer in QGIS.

Getting ready

If your QGIS installation isn't already configured for LAStools, you'll need to do so. You can find instructions for Windows in the official QGIS documentation here:

For OSX, you must use Wine. Instructions for configuring LAStools and Wine for OSX can be found here:

Once you have LAStools configured in OSX and...