How to Create a Pie Chart using Matplotlib

Need to create a pie chart using matplotlib?

If so, you can use the following template to create your pie chart:

import matplotlib.pyplot as plt

my_data = [value1,value2,value3,...]
my_labels = 'label1','label2','label3',...
plt.pie(my_data,labels=my_labels,autopct='%1.1f%%')
plt.title('My Title')
plt.axis('equal')
plt.show()

Next, I’ll review an example with the steps to create different types of pie charts.

Steps to Create a Pie Chart using Matplotlib

Step 1: Gather the Data for the Pie Chart

To start, you’ll need to gather the data for the pie chart.

For example, I gathered the following data about the status of tasks:

Tasks Pending	300
Tasks Ongoing	500
Tasks Completed	700

The goal is to create a pie chart based on the above data.

Step 2: Plot the Pie Chart using Matplotlib

Next, plot the pie chart using matplotlib.

You can use the template below to assist with the plotting of the chart:

import matplotlib.pyplot as plt

my_data = [value1,value2,value3,...]
my_labels = 'label1','label2','label3',...
plt.pie(my_data,labels=my_labels,autopct='%1.1f%%')
plt.title('My Title')
plt.axis('equal')
plt.show()

This is how the complete code would look like for our example:

import matplotlib.pyplot as plt

Tasks = [300,500,700]

my_labels = 'Tasks Pending','Tasks Ongoing','Tasks Completed'
plt.pie(Tasks,labels=my_labels,autopct='%1.1f%%')
plt.title('My Tasks')
plt.axis('equal')
plt.show()

Run the code in Python and you’ll get the following pie chart:

Step 3: Style the Chart

You can further style the pie chart by adding:

• Start angle
• Shadow
• Colors
• Explode component

This is the code that you can use for the styled chart:

import matplotlib.pyplot as plt

Tasks = [300,500,700]

my_labels = 'Tasks Pending','Tasks Ongoing','Tasks Completed'
my_colors = ['lightblue','lightsteelblue','silver']
my_explode = (0, 0.1, 0)
plt.pie(Tasks, labels=my_labels, autopct='%1.1f%%', startangle=15, shadow = True, colors=my_colors, explode=my_explode)
plt.title('My Tasks')
plt.axis('equal')
plt.show()

You’ll then get the chart below:

Create a Chart based on Pandas DataFrame

You can also create your pie chart based on pandas DataFrame.

For our example, the DataFrame (with the tasks data) would look like this:

from pandas import DataFrame

Data = {'Tasks': [300,500,700]}
df = DataFrame(Data,columns=['Tasks'])

print (df)

This is the DataFrame that you’ll get:

And here is the complete Python code to create the pie chart based on the data in the DataFrame:

from pandas import DataFrame
import matplotlib.pyplot as plt

Data = {'Tasks': [300,500,700]}
df = DataFrame(Data,columns=['Tasks'])

my_labels = 'Tasks Pending','Tasks Ongoing','Tasks Completed'
plt.pie(df,labels=my_labels,autopct='%1.1f%%')
plt.title('My Tasks')
plt.axis('equal')
plt.show()

Once you run the code, you’ll get the same pie chart:

You may then choose to style the chart using the following syntax:

from pandas import DataFrame
import matplotlib.pyplot as plt

Data = {'Tasks': [300,500,700]}
df = DataFrame(Data,columns=['Tasks'])

my_labels = 'Tasks Pending','Tasks Ongoing','Tasks Completed'
my_colors = ['lightblue','lightsteelblue','silver']
my_explode = (0, 0.1, 0)
plt.pie(df, labels=my_labels, autopct='%1.1f%%', startangle=15, shadow = True, colors=my_colors, explode=my_explode)
plt.title('My Tasks')
plt.axis('equal')
plt.show()

You’ll then get the following styled chart:

For other types of charts, you may want to check the following source that explains the steps to create scatter, line and bar charts using matplotlib.