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

Last Updated : 26 May, 2020

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.lognormvariate()

**lognormvariate()** is an inbuilt method of the random module. It is used to return a random floating point number with log-normal distribution.

Syntax : random.lognormvariate(mu, sigma)Parameters :mu : mean sigma : standard deviation, greater than 0Returns : a random log-normal distribution floating number

Example 1:

Python3 1== `

import the random module

import random

determining the values of the parameters

mu = 0 sigma = 0.25

using the lognormvariate() method

print(random.lognormvariate(mu, sigma))

`

Output :

0.8585439051088984

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

Python3 1== `

import the required libraries

import random import matplotlib.pyplot as plt

store the random numbers in a

list

nums = [] mu = 0 sigma = 0.25

for i in range(100): temp = random.lognormvariate(mu, sigma) 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 log-normal distribution.

Python3 1== `

import the required libraries

import random import matplotlib.pyplot as plt

store the random numbers in a list

nums = [] mu = 0 sigma = 0.25

for i in range(10000): temp = random.lognormvariate(mu, sigma) nums.append(temp)

plotting a graph

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

`

Output :