6 3 2 Random Module Explained

Key Concepts

The random module in Python provides functions to generate random numbers and perform random operations. The key concepts include:

• Generating Random Numbers
• Random Selection
• Shuffling Sequences
• Seeding the Random Number Generator

1. Generating Random Numbers

The random module allows you to generate random numbers within a specified range.

random.random()

Generates a random float number between 0.0 and 1.0.

import random

random_number = random.random()
print(random_number)  # Output: A random float between 0.0 and 1.0
    

random.randint(a, b)

Generates a random integer between a and b (inclusive).

import random

random_integer = random.randint(1, 10)
print(random_integer)  # Output: A random integer between 1 and 10
    

2. Random Selection

You can randomly select elements from a list or other sequences using the random module.

random.choice(seq)

Selects a random element from a non-empty sequence.

import random

fruits = ['apple', 'banana', 'cherry']
random_fruit = random.choice(fruits)
print(random_fruit)  # Output: A random fruit from the list
    

random.sample(population, k)

Returns a k length list of unique elements chosen from the population sequence.

import random

numbers = [1, 2, 3, 4, 5]
random_sample = random.sample(numbers, 3)
print(random_sample)  # Output: A list of 3 unique random numbers from the list
    

3. Shuffling Sequences

The random module allows you to shuffle the elements of a sequence in place.

random.shuffle(seq)

Shuffles the elements of a sequence in place.

import random

cards = ['Ace', 'King', 'Queen', 'Jack']
random.shuffle(cards)
print(cards)  # Output: The list 'cards' shuffled randomly
    

4. Seeding the Random Number Generator

Seeding the random number generator ensures that the sequence of random numbers can be reproduced.

random.seed(a=None)

Initializes the random number generator. If a is omitted or None, the current system time is used.

import random

random.seed(42)
print(random.random())  # Output: A specific random number based on the seed
    

Putting It All Together

By understanding and using the random module effectively, you can generate random numbers, select elements randomly, shuffle sequences, and control the randomness for reproducibility.

import random

# Generating random numbers
random_float = random.random()
random_integer = random.randint(1, 10)

# Random selection
fruits = ['apple', 'banana', 'cherry']
random_fruit = random.choice(fruits)
random_sample = random.sample(fruits, 2)

# Shuffling sequences
cards = ['Ace', 'King', 'Queen', 'Jack']
random.shuffle(cards)

# Seeding the random number generator
random.seed(42)
reproducible_random = random.random()

print(random_float)
print(random_integer)
print(random_fruit)
print(random_sample)
print(cards)
print(reproducible_random)