1 Goal


The goal of this tutorial is to learn how to remove all elements from a plot with ggplot. This could be useful if we want to produce a plot with certain characteristics.


2 Drawing with ggplot


# First we load the libraries
library(ggplot2)

# In this example we will use the open repository of plants classification Iris. 
data("iris")
str(iris)
## 'data.frame':    150 obs. of  5 variables:
##  $ Sepal.Length: num  5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ...
##  $ Sepal.Width : num  3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ...
##  $ Petal.Length: num  1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...
##  $ Petal.Width : num  0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...
##  $ Species     : Factor w/ 3 levels "setosa","versicolor",..: 1 1 1 1 1 1 1 1 1 1 ...
# Let's plot the petal length vs petal width
ggplot() + geom_point(data = iris, aes(x = Petal.Width, y = Petal.Length,color = Species))


3 Removing elements from the plot one by one


In this step we are going to remove elements from the plot one by one and see how it affects the look of the plot. The trick for most of the cases will be to declare element_blank the variable that defines the specific element


3.1 Legend


# To delete the legend we can declare the position of the legend to be none
ggplot() + geom_point(data = iris, aes(x = Petal.Width, y = Petal.Length,color = Species))+
  theme(legend.position = "none")