Book Image

R Data Visualization Recipes

By : Vitor Bianchi Lanzetta
Book Image

R Data Visualization Recipes

By: Vitor Bianchi Lanzetta

Overview of this book

R is an open source language for data analysis and graphics that allows users to load various packages for effective and better data interpretation. Its popularity has soared in recent years because of its powerful capabilities when it comes to turning different kinds of data into intuitive visualization solutions. This book is an update to our earlier R data visualization cookbook with 100 percent fresh content and covering all the cutting edge R data visualization tools. This book is packed with practical recipes, designed to provide you with all the guidance needed to get to grips with data visualization using R. It starts off with the basics of ggplot2, ggvis, and plotly visualization packages, along with an introduction to creating maps and customizing them, before progressively taking you through various ggplot2 extensions, such as ggforce, ggrepel, and gganimate. Using real-world datasets, you will analyze and visualize your data as histograms, bar graphs, and scatterplots, and customize your plots with various themes and coloring options. The book also covers advanced visualization aspects such as creating interactive dashboards using Shiny By the end of the book, you will be equipped with key techniques to create impressive data visualizations with professional efficiency and precision.
Table of Contents (19 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Dealing with over-plotting, alpha blending


Another popular technique is known as alpha blending. It consists on making points translucent, this way the audience gets to know if points are stacked or not.  Between all the techniques demonstrated so far, alpha blending must be the most popular one. This recipe teaches how to apply alpha blending using ggplot2, plotly, and ggvis.

How to do it...

  1. Set the alpha parameter to apply alpha blending to ggplot:
> library(ggplot2)
> sca1 <- ggplot( iris, aes( x = Petal.Length, y = Petal.Width))
> sca1 + geom_point( alpha = .5 , 
                     aes(shape = Species, colour = Species))

The following figure 2.7 shows alpha blending working:

Figure 2.7 - alpha blending with ggplot2.

  1. Setting alpha parameter with plotly will also apply alpha blending:
> library(plotly)
> sca9 <- plot_ly( iris, x = ~Petal.Length, y = ~Petal.Width, 
>                  type = 'scatter', mode = 'markers', alpha = .5, symbol = ~Species)
> sca9
  1. ggvis applies...