Book Image

Mastering Geospatial Analysis with Python

By : Silas Toms, Paul Crickard, Eric van Rees
Book Image

Mastering Geospatial Analysis with Python

By: Silas Toms, Paul Crickard, Eric van Rees

Overview of this book

Python comes with a host of open source libraries and tools that help you work on professional geoprocessing tasks without investing in expensive tools. This book will introduce Python developers, both new and experienced, to a variety of new code libraries that have been developed to perform geospatial analysis, statistical analysis, and data management. This book will use examples and code snippets that will help explain how Python 3 differs from Python 2, and how these new code libraries can be used to solve age-old problems in geospatial analysis. You will begin by understanding what geoprocessing is and explore the tools and libraries that Python 3 offers. You will then learn to use Python code libraries to read and write geospatial data. You will then learn to perform geospatial queries within databases and learn PyQGIS to automate analysis within the QGIS mapping suite. Moving forward, you will explore the newly released ArcGIS API for Python and ArcGIS Online to perform geospatial analysis and create ArcGIS Online web maps. Further, you will deep dive into Python Geospatial web frameworks and learn to create a geospatial REST API.
Table of Contents (23 chapters)
Title Page
Copyright and Credits
Packt Upsell
Geoprocessing with Geodatabases

Reading and writing raster data using GDAL

Here are some commands for reading and writing raster data with GDAL:

In: !gdalinfo --formats

This command lists all supported file formats in GDAL. For a summary including the CRS, use !gdalinfo without any prefixes:

In: !gdalinfo "C:\data\gdal\NE\50m_raster\NE1_50M_SR_W

Out: Driver: GTiff/GeoTIFF
     Files: C:\data\gdal\NE\50m_raster\NE1_50M_SR_W\NE1_50M_SR_W.tif
     Size is 10800, 5400
     Coordinate System is:
     GEOGCS["WGS 84",
     DATUM["WGS_1984", ...

You can convert a GeoTIFF to a JPEG file as follows:

In: !gdal_translate -of JPEG 

Out: Input file size is 10800, 5400
     0...10...20...30...40...50...60...70...80...90...100 - done.

The output, NE1_50M_SR_W.jpg, will look like this:

Now, let's open a GeoPackage using GDAL. GeoPackages can be either vector or raster-based, but in this case, we'll open a raster-based one, which becomes...