Boxplots in ggplot2

In this section, you will learn the ggplot2 codes for producing boxplots. While the syntax and default appearance may differ, these plots aim to compare distributions and identify outliers. If you need, you can add a few lines of code to make the base-R and ggplot2 graphs look the same. The choice of which plotting system to use is yours now.

Customized box plots

# Basic box plot
ggplot(ToothGrowth, aes(x=dose, y=len)) + 
  geom_boxplot(fill="gray")+
  labs(title="Plot of length per dose",x="Dose (mg)", y = "Length")+
  theme_classic()
# Change  automatically color by groups
bp <- ggplot(ToothGrowth, aes(x=dose, y=len, fill=dose)) + 
  geom_boxplot()+
  labs(title="Plot of length  per dose",x="Dose (mg)", y = "Length")
bp + theme_classic()

Change fill colors manually :

# Continuous colors
bp + scale_fill_brewer(palette="Blues") + theme_classic()
# Discrete colors
bp + scale_fill_brewer(palette="Dark2") + theme_minimal()
# Gradient colors
bp + scale_fill_brewer(palette="RdBu") + theme_minimal()