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

Using temporary scratch layers

When you just want to quickly draw some features on the map, temporary scratch layers are a great way of doing that without having to worry about file formats and locations for your temporary data. Go to Layer | Create Layer | New Temporary Scratch Layer... to create a new temporary scratch layer. As you can see in the following screenshot, all we need to do to configure this temporary layer is pick a Type for the geometry, a Layer name, and a CRS. Once the layer is created, we can add features and attributes as we would with any other vector layer:

As the name suggests, temporary scratch layers are temporary. This means that they will vanish when you close the project.


If you want to preserve the data of your temporary layers, you can either use Save as... to create a file or install the Memory Layer Saver plugin, which will make layers with memory data providers (such as temporary scratch layers) persistent so that they are restored when a project is closed...