Sign In Start Free Trial
Account

Add to playlist

Create a Playlist

Modal Close icon
You need to login to use this feature.
  • Python Geospatial Development
  • Toc
  • feedback
Python Geospatial Development

Python Geospatial Development

By : Westra
4.3 (4)
close
Python Geospatial Development

Python Geospatial Development

4.3 (4)
By: Westra

Overview of this book

Geospatial development links your data to locations on the surface of the Earth. 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. This book provides an overview of the major geospatial concepts, data sources, and toolkits. It starts by showing 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. Further on, 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 the GeoDjango framework. By the end of this book, you will be able to confidently use Python to write your own geospatial applications ranging from quick, one-off utilities to sophisticated web-based applications using maps and other geospatial data.
Table of Contents (15 chapters)
close
14
Index

Performance

Our DISTAL application is certainly working, but its performance leaves something to be desired. While the selectCountry.py and selectArea.py scripts run quickly, it can take two seconds or more for the showResults.py script to complete. Clearly, this isn't good enough: a delay like this is annoying to the user but would be disastrous for the server if it started to receive more requests than it could process.

Finding the problem

Adding some timing code to the showResults.py script soon shows where the bottleneck lies:

Calculating lat/long coordinate took 0.0110 seconds
Identifying place names took 0.0088 seconds
Generating map took 3.0208 seconds
Building HTML page took 0.0000 seconds

Clearly, the map-generation process is the problem here. Since it only took a fraction of a second to generate a map within the selectArea.py script, there's nothing inherent in the map-generation process that takes this long. So what has changed?

It could be that displaying the place names...

Unlock full access

Continue reading for free

A Packt free trial gives you instant online access to our library of over 7000 practical eBooks and videos, constantly updated with the latest in tech
bookmark search playlist font-size

Change the font size

margin-width

Change margin width

day-mode

Change background colour

Close icon Search
Country selected

Close icon Your notes and bookmarks

Delete Bookmark

Modal Close icon
Are you sure you want to delete it?
Cancel
Yes, Delete