Book Image

Mastering QGIS - Second Edition

By : Kurt Menke, GISP, Paolo Corti, Richard Smith Jr., GISP, Luigi Pirelli, John Van Hoesen, GISP
Book Image

Mastering QGIS - Second Edition

By: Kurt Menke, GISP, Paolo Corti, Richard Smith Jr., GISP, Luigi Pirelli, John Van Hoesen, GISP

Overview of this book

QGIS is an open source solution to GIS. It is widely used by GIS professionals all over the world. It is the leading alternative to the proprietary GIS software. Although QGIS is described as intuitive, it is also by default complex. Knowing which tools to use and how to apply them is essential to producing valuable deliverables on time. Starting with a refresher on the QGIS basics, this book will take you all the way through to creating your first custom QGIS plugin. From the refresher, we will recap how to create, populate, and manage a spatial database. You’ll also walk through styling GIS data, from creating custom symbols and color ramps to using blending modes. In the next section, you will discover how to prepare vector, heat maps, and create live layer effects, labeling, and raster data for processing. You’ll also discover advanced data creation and editing techniques. The last third of the book covers the more technical aspects of QGIS such as using LAStools and GRASS GIS’s integration with the Processing Toolbox, how to automate workflows with batch processing, and how to create graphical models. Finally, you will see how to create and run Python data processing scripts and write your own QGIS plugin with pyqgis. By the end of the book, you will understand how to work with all the aspects of QGIS, and will be ready to use it for any type of GIS work.
Table of Contents (19 chapters)
Mastering QGIS - Second Edition
Credits
Foreword
About the Authors
About the Reviewer
www.PacktPub.com
Preface
Index

Merging shapefiles


The Merge shapefiles to one tool merges (that is, combines) multiple input shapefiles into a new shapefile. The input shapefiles must be in a common coordinate reference system and should contain common attributes. For example, vector data is often provided in tiles or by political jurisdiction such as counties or states. In these cases, the data may need to be merged to form a seamless layer covering the study area. The Merge shapefiles to one tool that can be found by navigating to Vector | Data Management Tools will combine them:

In the Merge shapefiles dialog, you have the option to choose whether you wish to merge all shapefiles in a folder or pick individual shapefiles to merge:

  1. Depending on how your shapefiles are stored, you can do either of the following:

    • Keep Select by layers in the folder unchecked to merge all shapefiles in a directory

    • Check Select by layers in the folder to select individual files to merge

  2. If the previous option is enabled, choose the shapefile...