Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
QGIS Python Programming Cookbook, Second Edition

You're reading from   QGIS Python Programming Cookbook, Second Edition Automating geospatial development

Arrow left icon
Product type Paperback
Published in Mar 2017
Publisher Packt
ISBN-13 9781787124837
Length 464 pages
Edition 2nd Edition
Languages
Tools
Arrow right icon
Author (1):
Arrow left icon
Joel Lawhead Joel Lawhead
Author Profile Icon Joel Lawhead
Joel Lawhead
Arrow right icon
View More author details
Toc

Table of Contents (10) Chapters Close

Preface 1. Automating QGIS 2. Querying Vector Data FREE CHAPTER 3. Editing Vector Data 4. Using Raster Data 5. Creating Dynamic Maps 6. Composing Static Maps 7. Interacting with the User 8. QGIS Workflows 9. Other Tips and Tricks

Using the __geo_interface__ protocol

The __geo_interface__ is a newer protocol, created by Sean Gillies and targeted mainly at Python, to provide a string representation of geographical data following Python's built-ins protocol. The string representation for geographical data is basically GeoJSON. You can read more about this protocol here:

https://gist.github.com/sgillies/2217756

Two developers, Nathan Woodrow and Martin Laloux, refined a version of this protocol for QGIS Python data objects. This recipe borrows from their examples to provide a code snippet, which you can put at the beginning of your Python scripts to retrofit QGIS feature and geometry objects with a __geo_interface__ method.

Getting ready

This recipe requires no preparation.

How to do it...

We will create two functions: one for features and one for geometry. We'll then use Python's dynamic capability to patch the QGIS objects with a __geo_interface__ built-in method.

  1. First, we'll need the Python json module...
lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime
Banner background image