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In statistics, the **Gamma distribution** is often used to model probabilities related to waiting times.

The following examples show how to use the scipy.stats.gamma() function to plot one or more Gamma distributions in Python.

**Example 1: Plot One Gamma Distribution**

The following code shows how to plot a Gamma distribution with a shape parameter of **5** and a scale parameter of **3** in Python:

import numpy as np import scipy.stats as stats import matplotlib.pyplot as plt #define x-axis values x = np.linspace (0, 40, 100) #calculate pdf of Gamma distribution for each x-value y = stats.gamma.pdf(x, a=5, scale=3) #create plot of Gamma distribution plt.plot(x, y) #display plot plt.show()

The x-axis displays the potential values that a Gamma distributed random variable can take on and the y-axis shows the corresponding PDF values of the Gamma distribution with a shape parameter of 5 and scale parameter of 3.

**Example 2: Plot Multiple Gamma Distributions**

The following code shows how to plot multiple Gamma distributions with various shape and scale parameters:

import numpy as np import scipy.stats as stats import matplotlib.pyplot as plt #define three Gamma distributions x = np.linspace(0, 40, 100) y1 = stats.gamma.pdf(x, a=5, scale=3) y2 = stats.gamma.pdf(x, a=2, scale=5) y3 = stats.gamma.pdf(x, a=4, scale=2) #add lines for each distribution plt.plot(x, y1, label=shape=5, scale=3') plt.plot(x, y2, label='shape=2, scale=5') plt.plot(x, y3, label='shape=4, scale=2') #add legend plt.legend() #display plot plt.show()

Notice that the shape of the Gamma distribution can vary quite a bit depending on the shape and scale parameters.

**Related: **How to Plot Multiple Lines in Matplotlib

**Additional Resources**

The following tutorials explain how to plot other common distributions in Python:

How to Plot a Normal Distribution in Python

How to Plot a Chi-Square Distribution in Python