Book Image

Learning QGIS - Third Edition

By : Anita Graser
Book Image

Learning QGIS - Third Edition

By: Anita Graser

Overview of this book

QGIS is a user-friendly open source geographic information system (GIS) that runs on Linux, Unix, Mac OS X, and Windows. The popularity of open source geographic information systems and QGIS in particular has been growing rapidly over the last few years. Learning QGIS Third Edition is a practical, hands-on guide updated for QGIS 2.14 that provides you with clear, step-by-step exercises to help you apply your GIS knowledge to QGIS. Through clear, practical exercises, this book will introduce you to working with QGIS quickly and painlessly. This book takes you from installing and configuring QGIS to handling spatial data to creating great maps. You will learn how to load and visualize existing spatial data and create data from scratch. You will get to know important plugins, perform common geoprocessing and spatial analysis tasks and automate them with Processing. We will cover how to achieve great cartographic output and print maps. Finally, you will learn how to extend QGIS using Python and even create your own plugin.
Table of Contents (13 chapters)
Learning QGIS Third Edition
About the Author
About the Reviewer

Joining tabular data

In many real-life situations, we get additional non-spatial data in the form of spreadsheets or text files. The good news is that we can load XLS files by simply dragging them into QGIS from the file browser or using Add Vector Layer. Don't let the wording fool you! It really works without any geometry data in the file. The file can even contain more than one table. You will see the following dialog, which lets you choose which table (or tables) you want to load:

QGIS will automatically recognize the names and data types of columns in an XLS table. It's quite easy to tell because numerical values are aligned to the right in the attribute table, as shown in this screenshot:

We can also load tabular data from delimited text files, as we saw in Chapter 2, Viewing Spatial Data, when we loaded a point layer from a delimited text file. To load a delimited text file that contains only tabular data but no geometry information, we just need to enable the No geometry (attribute...