Book Image

Hands-On Geospatial Analysis with R and QGIS

By : Shammunul Islam, Brad Hamson
Book Image

Hands-On Geospatial Analysis with R and QGIS

By: Shammunul Islam, Brad Hamson

Overview of this book

Managing spatial data has always been challenging and it's getting more complex as the size of data increases. Spatial data is actually big data and you need different tools and techniques to work your way around to model and create different workflows. R and QGIS have powerful features that can make this job easier. This book is your companion for applying machine learning algorithms on GIS and remote sensing data. You’ll start by gaining an understanding of the nature of spatial data and installing R and QGIS. Then, you’ll learn how to use different R packages to import, export, and visualize data, before doing the same in QGIS. Screenshots are included to ease your understanding. Moving on, you’ll learn about different aspects of managing and analyzing spatial data, before diving into advanced topics. You’ll create powerful data visualizations using ggplot2, ggmap, raster, and other packages of R. You’ll learn how to use QGIS 3.2.2 to visualize and manage (create, edit, and format) spatial data. Different types of spatial analysis are also covered using R. Finally, you’ll work with landslide data from Bangladesh to create a landslide susceptibility map using different machine learning algorithms. By reading this book, you’ll transition from being a beginner to an intermediate user of GIS and remote sensing data in no time.
Table of Contents (12 chapters)
8
GRASS, Graphical Modelers, and Web Mapping

Web mapping

Web mapping can be useful to us; it allows our work to be exported to a web page. We will learn now how to export maps to web maps.

Web mapping in QGIS

We need to install the qgis2web plugin first to be able to export to a web map; particularly an OpenLayers or Leaflet map.

Here we will work with BGD_adm3_data.shp, and we will colorize polygons according to the different values of the value_Sh_2 attribute. To do so, we need to first right-click on the BGD_adm3_data layer and then click Properties. Then we need to click on Symbology, select Categorized, select value_Sh_2 as Column, click on Classify, and then click OK:

Now, we will get the following map, or something similar, at least:

Now, to create a web map...