Add space between histogram bars in Matplotlib

Last Updated : 24 Jan, 2021

Matplotlib is a plotting library in Python programming language and it’s by default numerical mathematics extension of NumPy library in python language. While programming in python language we use the matplotlib library package for graph and histogram visualizations. But while plotting histogram using matplotlib in python, it lacks division or space between adjacent bars. This makes histograms very tedious to work with and it becomes very difficult to interpret. In this article, we will study how to add space between histogram bars in matplotlib.
Let’s understand with this example:

Example 1: Creating a simple plot.

Python3

import matplotlib.pyplot as plt 
  
values = [1, 2, 3, 3, 4, 5, 6, 6, 7, 8] 
  
# Adjust the bar widths here 
plt.hist(values) 
  
plt.ylabel("Quantity") 
plt.xlabel("Value") 
plt.show()

Output:

Now we will add space between the histogram bars:

The space between bars can be added by using rwidth parameter inside the “plt.hist()” function. This value specifies the width of the bar with respect to its default width and the value of rwidth cannot be greater than 1.

Python3

import matplotlib.pyplot as plt 
  
values = [1, 2, 3, 3, 4, 5, 6, 6, 7, 8] 
  
# Adjust the bar widths here 
plt.hist(values, rwidth=0.7) 
  
plt.ylabel("Quantity") 
plt.xlabel("Value") 
plt.show()

Output:

Example 2: Creating a simple plot.

Python3

# Implementation of matplotlib function  
import matplotlib  
import numpy as np  
import matplotlib.pyplot as plt  
      
np.random.seed(10**7)  
n_bins = 20
x = np.random.randn(10000, 3)  
      
colors = ['green', 'blue', 'lime']  
    
plt.hist(x, n_bins, density = True,   
         histtype ='bar',  
         color = colors,  
         label = colors)  
    
plt.legend(prop ={'size': 10})    
plt.show()

Output:

With adding space:

Python3

# Implementation of matplotlib function  
import matplotlib  
import numpy as np  
import matplotlib.pyplot as plt  
      
np.random.seed(10**7)  
n_bins = 20
x = np.random.randn(10000, 3)  
      
colors = ['green', 'blue', 'lime']  
    
plt.hist(x, n_bins, density = True,   
         histtype ='bar',  
         color = colors,  
         label = colors, 
         rwidth = 0.5)  
    
plt.legend(prop ={'size': 10})  
    
plt.title('matplotlib.pyplot.hist() function Example\n\n',  
          fontweight ="bold")  
    
plt.show()