Python Geospatial Analysis Essentials

Erik Westra

• Verlag: Packt Publishing
• Jahr: 2015
• ISBN:
  9781782174516
• Auflage: 1
• Thema: Informatica
• Thema: Sviluppo di applicazioni

Python Geospatial Analysis Essentials

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Table of Contents

Python Geospatial Analysis Essentials

Credits

About the Author

About the Reviewers

www.PacktPub.com

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Why subscribe?

Free access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Errata

Piracy

Questions

1. Geospatial Analysis and Techniques

About geospatial analysis

Understanding geospatial data

Setting up your Python installation

Installing GDAL

Installing Shapely

Obtaining some geospatial data

Unlocking the shapefile

Analyzing the data

A program to identify neighboring countries

Summary

2. Geospatial Data

Geospatial data quality

Types of geospatial data

Shapefiles

Well-known text

Well-known binary

Spatial databases

Geospatial microformats

GeoJSON

GML

Digital elevation models

Raster basemaps

Multiband raster files

Sources of freely available geospatial data

Natural Earth Data

OpenStreetMap

US Census Bureau

World Borders Dataset

GLOBE

National Elevation Dataset

Reading and writing geospatial data using Python

Reading vector data

Writing vector data

Reading raster data

Writing raster data

Dealing with spatial reference systems

WGS84

Universal Transverse Mercator

Describing spatial reference systems

Transforming coordinates

Calculating lengths and areas

Geospatial data errors and how to fix them

Points

LineStrings

Linear Rings

Polygons

MultiPolygons

Fixing invalid geometries

Summary

3. Spatial Databases

Spatial database concepts

Installing a spatial database

Installing PostgreSQL

Installing PostGIS

Installing psycopg2

Accessing PostGIS from Python

Setting up a spatial database

Importing spatial data

Querying spatial data

Manipulating spatial data

Exporting spatial data

Summary

4. Creating Maps

Introducing Mapnik

Installing Mapnik

A taste of Mapnik

Building a map

Styling a map

Learning Mapnik

Datasources

Symbolizers

PointSymbolizer

LineSymbolizer

PolygonSymbolizer

TextSymbolizer

RasterSymbolizer

Map rendering

A working example

Next steps

Summary

5. Analyzing Geospatial Data

Libraries for spatial analysis

PyProj

NetworkX

Spatial analysis recipes

Calculating and comparing coordinates

Calculating lengths

Calculating areas

Calculating shortest paths

Summary

6. Building a Complete Geospatial Analysis System

Matching GPS data against a map

An overview of the GPS Heatmap system

Obtaining the necessary data

Obtaining GPS data

Downloading the road data

Implementing the GPS Heatmap system

Initializing the database

Importing the road data

Splitting the road data into segments

Constructing a network of directed road segments

Implementing the map matching algorithm

Generating the GPS heatmap

Further improvements

Summary

Index

Python Geospatial Analysis Essentials

Copyright © 2015 Packt Publishing

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First published: June 2015

Production reference: 1150615

Published by Packt Publishing Ltd.

Livery Place

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Birmingham B3 2PB, UK.

ISBN 978-1-78217-451-6

www.packtpub.com

Credits

Author

Erik Westra

Reviewers

Min Feng

Eric Hardin

Richard Marsden

Puneet Narula

Ryan Small

Commissioning Editor

Amarabha Banerjee

Acquisition Editor

Vinay Argekar

Content Development Editor

Mamata Walkar

Technical Editor

Pankaj Kadam

Copy Editors

Puja Lalwani

Laxmi Subramanian

Project Coordinator

Shipra Chawhan

Proofreaders

Stephen Copestake

Safis Editing

Indexer

Tejal Soni

Production Coordinator

Manu Joseph

Cover Work

Manu Joseph

About the Author

Erik Westra has been a professional software developer for over 25 years now, and he has worked almost exclusively in Python for the past decade. Erik's early interest in graphical user interface design led to the development of one of the most advanced urgent courier dispatch systems used by messenger and courier companies worldwide.

In recent years, Erik has been involved in the design and implementation of systems matching seekers and providers of goods and services across a range of geographical areas, as well as real-time messaging and payment systems. This work has included the creation of real-time geocoders and map-based views of constantly changing data. Erik is based in New Zealand, and works for companies worldwide.

Erik is also the author of the titles Python Geospatial Development and Building Mapping Applications with QGIS, both by Packt Publishing.

About the Reviewers

Min Feng completed his PhD degree in cartography and geographic information systems in 2008 and has been working at the Global Land Cover Facility (GLCF), University of Maryland, Chinese Academy of Sciences (CAS), and Global Resource Information Database (GRID) of the United Nations Environment Programme (UNEP). Dr. Feng has been engaged in global high-resolution land cover and change research and is an expert with high-performance geospatial data processing, geospatial model sharing, and integrated simulation. His work has been published in top-ranking remote sensing and GIS journals. Dr. Feng is familiar with OGC/ISO standards and open source tools and libraries, and is also capable of programming using many languages, including C/C++, Java, Python, R, and IDL. He has also reviewed Learning QGIS – Second Edition, Packt Publishing.

Eric Hardin works in the defense and aerospace industry as a software engineer with an international research and engineering company. While pursuing a PhD in physics, he used geospat...