Book Image

Learning QGIS 2.0

By : Anita Graser
Book Image

Learning QGIS 2.0

By: Anita Graser

Overview of this book

QGIS is a user friendly open source geographic information system (GIS) that runs on Linux, Unix, Mac OSX, and Windows. The popularity of open source geographic information systems and QGIS in particular has been growing rapidly over the last few years. More and more companies and institutions are adopting QGIS and even switching to QGIS as their main GIS. Learning QGIS 2.0 is a practical, hands-on guide that provides you with clear, step-by-step exercises that will help you to apply your GIS knowledge to QGIS. Containing a number of clear, practical exercises, this book will introduce you to working with QGIS, quickly and painlessly. If you want to take advantage of the wide range of functionalities that QGIS offers, then this is the book for you. This book takes you from installing and configuring QGIS, through handling spatial data to creating great maps. You will learn how to load and visualize existing spatial data and how to create data from scratch. You will perform common geoprocessing and spatial analysis tasks and automate them. We will cover how to achieve great cartographic output and print maps. You will learn everything you need to know to handle spatial data management, processing, and visualization tasks in QGIS.
Table of Contents (12 chapters)

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 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 just one table. You will see the following dialog, which lets you choose which table(s) 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 numeric values are right-aligned in the attribute table as shown in the following screenshot:

We can also load tabular data from delimited text files like 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 only contains tabular data but no geometry information, we just need to enable the No geometry (attribute table only...