How to plot two histograms together in Matplotlib? (original) (raw)

Last Updated : 12 Sep, 2022

Creating the histogram provides the visual representation of data distribution. By using a histogram we can represent a large amount of data and its frequency as one continuous plot.

How to plot a histogram using Matplotlib

For creating the Histogram in Matplotlib we use hist() function which belongs to pyplot module. For plotting two histograms together, we have to use hist() function separately with two datasets by giving some settings.

Syntax of matplotlib.pyplot.hist

matplotlib.pyplot.hist(x, bins, edgecolor color, label)

Example 1:

Here, we are simply taking two series using the Numpy random and passing both series to the hist()function, and we’re using the same plot to plot two histograms together.

Python3

import matplotlib.pyplot as plt

import numpy as np

series1 = np.random.randn( 500 , 1 )

series2 = np.random.randn( 400 , 1 )

plt.hist(series1)

plt.hist(series2)

plt.show()

Output:

Example 2:

Here, we are using label, edgecolor, and opacity.

Python3

import matplotlib.pyplot as plt

import numpy as np

from numpy.lib.histograms import histogram

series1 = np.random.randn( 500 , 1 )

series2 = np.random.randn( 400 , 1 )

plt.hist(series1, label = 'series1' , alpha = . 8 , edgecolor = 'red' )

plt.hist(series2, label = 'series2' , alpha = 0.7 , edgecolor = 'yellow' )

plt.legend()

plt.show()

Output:

Example 3:

Histograms represent two age groups using given data.

Python3

import matplotlib.pyplot as plt

age_g1 = [ 1 , 3 , 5 , 10 , 15 , 17 , 18 , 16 , 19 ,

`` 21 , 23 , 28 , 30 , 31 , 33 , 38 , 32 ,

`` 40 , 45 , 43 , 49 , 55 , 53 , 63 , 66 ,

`` 85 , 80 , 57 , 75 , 93 , 95 ]

age_g2 = [ 6 , 4 , 15 , 17 , 19 , 21 , 28 , 23 , 31 ,

`` 36 , 39 , 32 , 50 , 56 , 59 , 74 , 79 , 34 ,

`` 98 , 97 , 95 , 67 , 69 , 92 , 45 , 55 , 77 ,

`` 76 , 85 ]

plt.hist(age_g1, label = 'Age group1' , bins = 14 , alpha = . 7 , edgecolor = 'red' )

plt.hist(age_g2, label = "Age group2" , bins = 14 , alpha = . 7 , edgecolor = 'yellow' )

plt.legend()

plt.show()

Output:

Example 4:

Changing bar color from the default

Python3

import matplotlib.pyplot as plt

age_g1 = [ 1 , 3 , 5 , 10 , 15 , 17 , 18 , 16 , 19 , 21 ,

`` 23 , 28 , 30 , 31 , 33 , 38 , 32 , 40 , 45 ,

`` 43 , 49 , 55 , 53 , 63 , 66 , 85 , 80 , 57 ,

`` 75 , 93 , 95 ]

age_g2 = [ 6 , 4 , 15 , 17 , 19 , 21 , 28 , 23 , 31 , 36 ,

`` 39 , 32 , 50 , 56 , 59 , 74 , 79 , 34 , 98 , 97 ,

`` 95 , 67 , 69 , 92 , 45 , 55 , 77 , 76 , 85 ]

plt.hist(age_g1, label = 'Age group1' , alpha = . 7 , color = 'red' )

plt.hist(age_g2, label = "Age group2" , alpha = . 5 ,

`` edgecolor = 'black' , color = 'yellow' )

plt.legend()

plt.show()

Output: