Book Image

QGIS Python Programming Cookbook

Book Image

QGIS Python Programming Cookbook

Overview of this book

Table of Contents (16 chapters)
QGIS Python Programming Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Adding elevation data to line vertices using a digital elevation model


If you have a transportation route through some terrain, it is useful to know the elevation profile of that route. This operation can be accomplished using the points that make up the line along the route to query a DEM and to assign elevation values to that point. In this recipe, we'll do exactly that.

Getting ready

You will need an elevation grid and a route. You can download this dataset from https://geospatialpython.googlecode.com/svn/path.zip.

Unzip the path directory containing a shapefile and the elevation grid. Place the whole path directory in your qgis_data/rasters directory.

How to do it...

We will need two processing algorithms to complete this recipe. We will load the raster and vector layers, convert the line feature to points, and then use these points to query the raster. The resulting point dataset will serve as the elevation profile for the route. To do this, we need to perform the following steps:

  1. Start QGIS...