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

Geocoding addresses

Geocoding is the process of turning an address into earth coordinates. Geocoding requires a comprehensive dataset that ties zip codes, cities, streets, and street numbers (or street number ranges) to the coordinates. In order to have a geocoder that works for any address in the world with reasonable accuracy, you need to use a cloud service because geocoding datasets are very dense and can be quite large. Creating a geocoding dataset for any area beyond a few square miles requires a significant amount of resources. There are several services available, including Google and MapQuest. In QGIS, the easiest way to access these services is through the QGIS Python GeoCoding plugin. In this recipe, we'll use this plugin to programmatically geocode an address.

Getting ready

You will need to install the QGIS Python GeoCoding plugin by Alessandro Pasotti for this exercise, as follows:

  1. From the QGIS Plugins menu, select Manage and Install Plugins....

  2. In the Plugins dialog search box...