Book Image

Python Geospatial Development - Second Edition - Second Edition

By : Erik Westra
Book Image

Python Geospatial Development - Second Edition - Second Edition

By: Erik Westra

Overview of this book

Geospatial development links your data to places on the Earth's surface. Writing geospatial programs involves tasks such as grouping data by location, storing and analyzing large amounts of spatial information, performing complex geospatial calculations, and drawing colorful interactive maps. In order to do this well, you'll need appropriate tools and techniques, as well as a thorough understanding of geospatial concepts such as map projections, datums and coordinate systems. Python Geospatial Development - Second Edition teaches you everything you need to know about writing geospatial applications using Python. No prior knowledge of geospatial concepts, tools or techniques is required. The book guides you through the process of installing and using various toolkits, obtaining geospatial data for use in your programs, and building complete and sophisticated geospatial applications in Python. Python Geospatial Development teaches you everything you need to know about writing geospatial applications using Python. No prior knowledge of geospatial concepts, tools or techniques is required. The book guides you through the process of installing and using various toolkits, obtaining geospatial data for use in your programs, and building complete and sophisticated geospatial applications in Python. This book provides an overview of the major geospatial concepts, data sources and toolkits. It teaches you how to store and access spatial data using Python, how to perform a range of spatial calculations, and how to store spatial data in a database. Because maps are such an important aspect of geospatial programming, the book teaches you how to build your own “slippy map” interface within a web application, and finishes with the detailed construction of a geospatial data editor using Geodjango. Whether you want to write quick utilities to solve spatial problems, or develop sophisticated web applications based around maps and geospatial data, this book includes everything you need to know.
Table of Contents (18 chapters)
Python Geospatial Development
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

About DISTAL


The DISTAL application will have the following basic workflow:

  1. The user starts by selecting the country they wish to work with:

  2. A simple map of the country is displayed:

  3. The user selects a desired radius in miles, and clicks on a point within the country:

  4. The system identifies all of the cities and towns within the given radius of that point:

  5. Finally, the resulting features are displayed at a higher resolution for the user to view or print:

While we haven't yet looked at the map-rendering and user-interface aspects of geospatial applications, we do know enough to proceed with a very simple implementation of the DISTAL system. In this implementation, we will make use of basic CGI scripts and a "black box" map-generator module, while focusing on the data storage and manipulation aspects of the DISTAL application.

Note that Chapter 8, Using Python and Mapnik to Produce Maps, will look at the details of generating maps using the Mapnik map-rendering toolkit, while Chapter 9, Putting It...