Python’s Random Module: A Comprehensive Guide

The random module is essential for data science, data engineering, and machine learning. It’s also popular in game development and widely used in software design. This in-built Python function is straightforward to use once you understand when and how to apply it.

In this article, we discuss the random module and its various uses.

Generating Random Numbers

The random function generates computer-chosen random numbers based on user specifications. You can select a specific set or range of numbers, and the computer produces numbers based on your commands. To start, import the random module:

Key Functions of the Random Module

1. Generate a Random Integer (randint)

import random
a = random.randint(1, 7)
print(a)
# Output could be any number from 1 to 7

Here, random.randint sets the range from 1 to 7, and any number within this range can be generated.

2. Generate a Random Integer (Using randrange)

Another function, randrange, also generates numbers but excludes the upper limit:

a = random.randrange(1, 7)
print(a)
# Output will be any number from 1 to 6

3. Generate a Random Float (random)

The random.random() function produces a float between 0 and 1:

a = random.random()
print(a)
# Output: a float between 0 and 1

4. Generate a Float Within a Range (uniform)

To generate a float within a specified range, use random.uniform:

a = random.uniform(1, 3)
print(a)
# Output: a float between 1 and 3

5. Select a Random Item from a List (choice)

If you have a list, you can select a random element:

l = [2, 5, 9, -5, 89, 12, 56]
a = random.choice(l)
print(a)
# Output: any number from list `l`

6. Shuffle List Elements (shuffle)

To shuffle a list, use random.shuffle:

l = [2, 5, 9, -5, 89, 12, 56]
random.shuffle(l)
print(l)
# Output: a rearranged version of `l`

Real-World Example: Rock-Paper-Scissors Game

Suppose,

Rock wins against Scissor

Scissor win against paper

Paper wins against rock

0 for rock

1 for paper

2 for scissor

USER	COMPUTER	RESULT
Input	Input	Output
0	0	Draw
0	1	Computer win
0	2	User win
1	0	User win
1	1	Draw
1	2	Computer win
2	0	Computer win
2	1	User win
2	2	Draw

The random module can be used to make games. Here’s an example of a simple Rock-Paper-Scissors game:

import random

user = int(input("Enter a number (0 for rock, 1 for paper, 2 for scissors): "))
if user < 0 or user > 2:
    print("You entered an invalid number.")
else:
    computer = random.randint(0, 2)
    print(f"Computer chose: {computer}")

    if user == computer:
        print("The game is a draw")
    elif (user == 0 and computer == 2) or (user == 2 and computer == 1) or (user == 1 and computer == 0):
        print("User wins!")
    else:
        print("Computer wins!")

In this code, the computer generates a random choice between 0 and 2, representing rock, paper, and scissors, and the program compares it with the user’s input.