random.expovariate() function in Python (original) (raw)

Last Updated : 23 Dec, 2021

random module is used to generate random numbers in Python. Not actually random, rather this is used to generate pseudo-random numbers. That implies that these randomly generated numbers can be determined.

random.expovariate()

**expovariate()** is an inbuilt method of the random module. It is used to return a random floating point number with exponential distribution.

Syntax : random.expovariate(lambda)Parameters :lambda : a non zero valueReturns : a random exponential distribution floating number if the parameter is positive, the results range from 0 to positive infinity if the parameter is negative, the results range from 0 to negative infinity

Example 1:

Python3 1== `

import the random module

import random

determining the values of the parameter

lambda = 1.5

using the expovariate() method

print(random.expovariate(lambda))

`

Output :

0.22759592233982198

Example 2: We can generate the number multiple times and plot a graph to observe the exponential distribution.

Python3 1== `

import the required libraries

import random import matplotlib.pyplot as plt

store the random numbers in a

list

nums = [] alpha = 3

for i in range(100): temp = random.paretovariate(alpha) nums.append(temp)

plotting a graph

plt.plot(nums) plt.show()

`

Output : Example 3: We can create a histogram to observe the density of the exponential distribution.

Python3 1== `

import the required libraries

import random import matplotlib.pyplot as plt

store the random numbers in a list

nums = [] lambda = 1.5

for i in range(10000): temp = random.expovariate(lambda) nums.append(temp)

plotting a graph

plt.hist(nums, bins = 200) plt.show()

`

Output :