Increase border line thickness of ggplot2 plot in R

In this article, we are going to see how to change the borderline thickness using the ggplot2 bar plot in R Programming Language.

First, you need to install the ggplot2 package if it is not previously installed in R Studio. To install and load write the below command in R Console :

install.packages("ggplot2")
library(ggplot2)

For creating a simple bar plot we will use the function geom_bar( ).

Syntax:

geom_bar(stat, fill, color, width)

Parameters : 

• stat : Set the stat parameter to identify the mode.
• fill : Represents color inside the bars.
• color : Represents color of outlines of the bars.
• width : Represents width of the bars.

Let’s a Data Frame which has two vectors “match” and “run” and store it in a variable “runs”.

R

# Inserting data
runs <- data.frame(match=c("M-1","M-2","M-3","M-4"),
                   run=c(33, 45, 66, 50))

head(runs)

Output:

Bar Plot

R

# Bar Plot
library(ggplot2)


IPL <-ggplot(data=runs, aes(x=match, y=run)) +
  geom_bar(stat="identity",fill="white",color="black")+
  theme_classic()

IPL

Output:

Increasing the Border Thickness

Inside the function geom_bar( ), use the keyword size and assign a value to change the thickness of the border. In our case, we have assigned a value of 2 to the size. We can observe that the thickness of the border line has increased.

R

# Changing the border thickness
library(ggplot2)


IPL <-ggplot(data=runs, aes(x=match, y=run)) +
  geom_bar(stat="identity",fill="white",color="black",size=2)+
  theme_classic()

IPL

Output:

Example 2: Consider a Data Frame which consists of information about marks obtained by students in an exam.

R

# Inserting data
marks <- data.frame(student=c("S-1","S-2","S-3","S-4","S-5"),
                   mark=c(90, 85, 75, 78, 98))

# Changing the border thickness
library(ggplot2)


RESULT <-ggplot(data=marks, aes(x=student, y=mark)) +
  geom_bar(stat="identity",fill="yellow",color="navy",size=4,alpha=0.1)+
  theme_classic()

RESULT

Output: