Book Image

R Graphs Cookbook Second Edition

Book Image

R Graphs Cookbook Second Edition

Overview of this book

Table of Contents (22 chapters)
R Graphs Cookbook
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Creating a conditional histogram


A histogram is one of the simplest ways to visualize the univariate distribution. Sometimes, we need to produce a histogram for each group in order to compare the distribution in a subgroup of another categorical variable. In this recipe, we will see how we can create a conditional histogram using the lattice functionality.

Getting ready

To visualize a conditional histogram, we need at least one numeric variable and one categorical variable. We have all this information in the dataset that we have simulated in earlier recipes. Here, we will reproduce the same cross-tabulation raw data with the following code:

# Set a seed value to make the data reproducible
set.seed(12345)
cross_tabulation_data <-data.frame(disA=rnorm(n=100,mean=20,sd=3),
                disB=rnorm(n=100,mean=25,sd=4),
                disC=rnorm(n=100,mean=15,sd=1.5),
                age=sample((c(1,2,3,4)),size=100,replace=T),
                sex=sample(c("Male","Female"),size=100,replace...