Python Geospatial Analysis Cookbook

封面

版权页

Credits

About the Author

About the Reviewers

www.PacktPub.com

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Preface

What this book covers

What you need for this book

Who this book is for

Sections

Conventions

Reader feedback

Customer support

Chapter 1. Setting Up Your Geospatial Python Environment

Introduction

Installing virtualenv and virtualenvwrapper

Installing pyproj and NumPy

Installing shapely matplotlib and descartes

Installing pyshp geojson and pandas

Installing SciPy PySAL and IPython

Installing GDAL and OGR

Installing GeoDjango and PostgreSQL with PostGIS

Chapter 2. Working with Projections

Introduction

Discovering projection(s) of a Shapefile or GeoJSON dataset

Listing projection(s) from a WMS server

Creating a projection definition for a Shapefile if it does not exist

Batch setting the projection definition of a folder full of Shapefiles

Reprojecting a Shapefile from one projection to another

Chapter 3. Moving Spatial Data from One Format to Another

Introduction

Converting a Shapefile to a PostGIS table using ogr2ogr

Batch importing a folder of Shapefiles into PostGIS using ogr2ogr

Batch exporting a list of tables from PostGIS to Shapefiles

Converting an OpenStreetMap (OSM) XML to a Shapefile

Converting a Shapefile (vector) to a GeoTiff (raster)

Converting a raster (GeoTiff) to a vector (Shapefile) using GDAL

Creating a Shapefile from point data stored in Microsoft Excel

Converting an ESRI ASCII DEM to an image height map

Chapter 4. Working with PostGIS

Introduction

Executing a PostGIS ST_Buffer analysis query and exporting it to GeoJSON

Finding out whether a point is inside a polygon

Splitting LineStrings at intersections using ST_Node

Checking the validity of LineStrings

Executing a spatial join and assigning point attributes to a polygon

Conducting a complex spatial analysis query using ST_Distance()

Chapter 5. Vector Analysis

Introduction

Clipping LineStrings to an area of interest

Splitting polygons with lines

Finding the location of a point on a line using linear referencing

Snapping a point to the nearest line

Calculating 3D ground distance and total elevation gain

Chapter 6. Overlay Analysis

Introduction

Punching holes in polygons with a symmetric difference operation

Union polygons without merging

Union polygons with merging (dissolving)

Performing an identity function (difference + intersection)

Chapter 7. Raster Analysis

Introduction

Loading a DEM USGS ACSII CDED into PostGIS

Creating an elevation profile

Creating a hillshade raster from your DEM with ogr

Generating slope and aspect images from your DEM

Merging rasters to generate a color relief map

Chapter 8. Network Routing Analysis

Introduction

Finding the Dijkstra shortest path with pgRouting

Finding the Dijkstra shortest path with NetworkX in pure Python

Generating evacuation polygons based on an indoor shortest path

Creating centerlines from polygons

Building an indoor routing system in 3D

Calculating indoor route walk time

Chapter 9. Topology Checking and Data Validation

Introduction

Creating a rule – only one point inside a polygon

A point must be on the starting and ending nodes of a line only

LineStrings must not overlap

A LineString must not have dangles

A polygon centroid must be within a specific distance of a line

Chapter 10. Visualizing Your Analysis

Introduction

Generating a leaflet web map with Folium

Setting up TileStache to serve tiles

Visualizing DEM data with Three.js

Draping an orthophoto over a DEM

Chapter 11. Web Analysis with GeoDjango

Introduction

Setting up a GeoDjango web application

Creating an indoor web routing service

Visualizing an indoor routing service

Creating an indoor route-type service

Creating an indoor route from room to room

Appendix A. Other Geospatial Python Libraries

Appendix B. Mapping Icon Libraries