Random number generation

2.2.3 Additional Programming Techniques

Additional Programming Techniques — Note 12 of 12

Be able to create and use random numbers in a program

What you need to know

Random number generation allows programs to produce unpredictable values within a specified range. This is useful for games (dice rolls, card draws), simulations, testing, and security. In OCR pseudocode the syntax is random(min, max); in Python you use the random module.

What to know

random(min, max) generates a random integer between min and max inclusive (OCR pseudocode).
In Python: import random, then random.randint(min, max) for integers.
random.randint() is inclusive of both endpoints.
Store the random value in a variable if it will be used more than once.
Useful for: dice rolls, random questions, game outcomes, test data generation.
Can generate both integer and real (float) random numbers.

Code examples

Random number generation

python

import random

# Random integer between 1 and 6 (dice roll)
dice = random.randint(1, 6)
print("You rolled:", dice)

# Random float between 0.0 and 1.0
chance = random.random()
print("Random chance:", chance)

# Random choice from a list
colours = ["red", "blue", "green"]
pick = random.choice(colours)
print("Chosen colour:", pick)

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Random number generation

2.2.3 Additional Programming Techniques

Practise exam questions

Additional Programming Techniques — Note 12 of 12

Be able to create and use random numbers in a program

What you need to know

What to know

random(min, max) generates a random integer between min and max inclusive (OCR pseudocode).
In Python: import random, then random.randint(min, max) for integers.
random.randint() is inclusive of both endpoints.
Store the random value in a variable if it will be used more than once.
Useful for: dice rolls, random questions, game outcomes, test data generation.
Can generate both integer and real (float) random numbers.

Code examples

Random number generation

python

import random

# Random integer between 1 and 6 (dice roll)
dice = random.randint(1, 6)
print("You rolled:", dice)

# Random float between 0.0 and 1.0
chance = random.random()
print("Random chance:", chance)

# Random choice from a list
colours = ["red", "blue", "green"]
pick = random.choice(colours)
print("Chosen colour:", pick)

Ready to test yourself?

Practise 2.2.3 questions

← Previous notearrays2.2.3 Additional Programming Techniques Next topic →Anticipating misuse, Authentication2.3.1 Defensive Design

Back to Additional Programming Techniques

Revise another OCR GCSE topic: Programming Fundamentals