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 ShapeEditor


As we have seen, shapefiles are commonly used to store, make available, and transfer geospatial data. We have worked with shapefiles extensively in this book, obtaining freely-available geospatial data in shapefile format, writing programs to load data from a shapefile, and creating shapefiles programmatically.

While it is easy enough to edit the attributes associated with a shapefile's features, editing the features themselves is a lot more complicated. One approach would be to install a GIS system and use it to import the data, make changes, and then export the data into another shapefile. While this works, it is hardly convenient if all you want to do is make a few changes to a shapefile's features. It would be much easier if we had a web application specifically designed for editing shapefiles.

This is precisely what we are going to implement: a web-based shapefile editor. Rather unimaginatively, we'll call this program ShapeEditor.

The following flowchart depicts the...