Tutorial Gateway

Pie Chart in R Programming

by

The Pie Chart in R is very useful to display the region wise sales, Country wide customers, Sales by Country etc.

In this article we will show you, How to Create a Pie Chart, Format its color, borders, adding legions, and creating 3D Pie Chart in R Programming language with example.

R Pie Chart Syntax

The basic syntax to draw pie chart in R Programming is as shown below

pie(x, labels = names(x), col = NULL, main = NULL)

and the complex syntax behind this pie is:

pie(x, labels = names(x), edges = 200, radius = 0.8, clockwise = FALSE, 
     init.angle = if(clockwise) 90 else 0, density = NULL, angle = 45, 
     col = NULL, border = NULL, lty = NULL, main = NULL, ..)

There are many arguments supported by the Pie Chart in R programming language, and following are the most used arguments in real-time:

  • x: Please specify a vector of non-negative numeric values. This will decide the size of each Pie chart slice
  • labels: This argument will help us to pass names to each slice.
  • edges: Th numeric value accepted by this argument will change the outer circle of the pie. We strictly recommend to keep the value to default 200.
  • radius: This is the radius of the Pie Chart circle whose value is between -1 and 1
  • clockwise: It is a Boolean value indicating if slices are drawn in the clockwise direction or counter-clockwise direction. By default, it will be counter-clockwise
  • init.angle: This argument can help you to specify the starting angle (in degrees) for slices. By default it is 0. If the clockwise is TRUE then init.angle will become 90 degrees.
  • density: Please specify the shading lines density (in lines per inch). By default it is NULL, means no shading lines.
  • angle: You can assign the slope of shading lines using this argument.
  • col: Please specify the vector of colors you want to use for your pie chart. By default, it will use set of 6 pascal colors.
  • border, lty: This argument (possibly vector) passed to polygon, which draws each slice of a pie.
  • Main: You can provide the Title for your Pie chart.

Create basic R Pie Chart

In this example we will show you, How to create a Pie chart using the vectors

# Basic Pie Chart in R Example

values <-  c(906, 264, 289, 339, 938)
countries <-  c("India","Sri Lanka","Nepal","Bhutan", "China")

pie(values, labels = countries)

OUTPUT

Pie Chart in R Programming 1

ANALYSIS

First we declared one vector of random numbers and another vector of random countries

values <-  c(906, 264, 289, 339, 938)
countries <-  c("India","Sri Lanka","Nepal","Bhutan", "China")

Next we used the pie to draw the pie chart. From the below code snippet you can observe that, Slice size will be decided on values.

pie(values, labels = countries)

Changing Borders and lty of a Pie Chart in R Programming

In this example we will show you, How to change the Pie chart border color and changing the line style using border and lty arguments.

# R Pie Chart - Border and lty Example

values <-  c(906, 264, 289, 339, 938)
countries <-  c("India","Sri Lanka","Nepal","Bhutan", "China")

pie(values, labels = countries, border = "red", lty = 2)

OUTPUT

Pie Chart in R Programming 2

TIP: To assign different border colors use Vector of colors. For example, border = c(“red”, “green”, “black”…)

Create a Pie Chart in R Programming

In this example we will show you, How to create a Pie Chart using the external data. For this, we are importing data from the csv file using read.csv function. I suggest you to refer R Read CSV article to understand the steps involved in csv file import

# R Pie Chart Example
getwd()

employee <- read.csv("Products.csv", TRUE, sep = ",")
data <- aggregate(employee$SalesAmount, 
                  by=list(employee$EnglishCountryRegionName), FUN=sum)
print(data)

pie(data$x, data$Group.1)

OUTPUT

Pie Chart in R Programming 3

ANALYSIS

From the below code snippet you can observe that, we used the Aggregate function to find the total amount of sales in each country, or we can say Sum of Sales Amount Group By Countries.

data <- aggregate(employee$SalesAmount, 
                  by=list(employee$EnglishCountryRegionName), FUN=sum)

Above statement will return the output as a List. So, we are using the $ to extract data from List

pie(data$x, data$Group.1)

Change Colors of Pie Chart in R

In this example we will show you, How to change the Pie chart Slice colors using col argument

# R Pie Chart - Changing Colors Example
getwd()

employee <- read.csv("Products.csv", TRUE, sep = ",")
data <- aggregate(employee$SalesAmount, 
                  by=list(employee$EnglishCountryRegionName), FUN=sum)
print(data)

pie(data$x, data$Group.1, col = rainbow(length(data$x)))

OUTPUT

Pie Chart in R Programming 4

Change Slice Direction & Name of Pie Chart

In this example we will show you, How to change the R Pie chart Slice direction using clockwise argument, and assign title/name to the pie chart using main argument.

# R Pie Chart - Changing Slic Direction & Assigning Name
getwd()

employee <- read.csv("Products.csv", TRUE, sep = ",")
data <- aggregate(employee$SalesAmount, 
                  by=list(employee$EnglishCountryRegionName), FUN=sum)
print(data)

pie(data$x, data$Group.1, col = rainbow(length(data$x)),
    clockwise = TRUE, main = "Sales By COuntry")

OUTPUT

Pie Chart in R Programming 5

Adding Legend to Pie Chart

In this example we will show you, How to Add Legend to the R Pie chart using legend function

# R Pie Chart - Adding Legend & Custom Colors
getwd()

employee <- read.csv("Products.csv", TRUE, sep = ",")
data <- aggregate(employee$SalesAmount, 
                  by=list(employee$EnglishCountryRegionName), FUN=sum)
print(data)
cols = c("red", "orange", "grey", "white", "black", "yellow")

pie(data$x, data$Group.1, col = cols,  main = "Sales By COuntry")

legend("topright", c("Australia","Canada","France",
                     "Germany", "United Kingdom", "United States"), 
       cex = 0.8, fill = cols)

OUTPUT

Pie Chart in R Programming 6

Changing Density of a Pie Chart Slice

In this example we will show you, How to change the Slice density using density argument

# R Pie Chart - Changing the Density
getwd()

employee <- read.csv("Products.csv", TRUE, sep = ",")
data <- aggregate(employee$SalesAmount, 
                  by=list(employee$EnglishCountryRegionName), FUN=sum)
print(data)
cols = c("red", "orange", "grey", "blue", "black", "yellow")

pie(data$x, data$Group.1, col = cols,  density = 50, 
    main = "Sales By Country")

legend("topright", c("Australia","Canada","France",
                     "Germany", "United Kingdom", "United States"), 
       cex = 0.7, fill = cols)

OUTPUT

Pie Chart in R Programming 7

3D Pie Chart in R Programming

In this example we will show you, How to create a 3D Pie chart in R Programming. In order to draw the 3D Pie chart we need pie3D function, and to use this function we have to add plotrix library (package) to our R Studio

# 3D R Pie Chart Example

employee <- read.csv("Products.csv", TRUE, sep = ",")
data <- aggregate(employee$SalesAmount, 
                  by=list(employee$EnglishCountryRegionName), FUN=sum)
print(data)

pie3D(data$x,labels = data$Group.1, explode = 0.1, 
      main = "3D Pie Chart in R ")

OUTPUT

Pie Chart in R Programming 8

Thank You for Visiting Our Blog