Lua random()

In Lua, the math.random() function is used to generate pseudo-random numbers. It can be used with or without an argument and in conjunction with the math.randomseed() function to control the sequence of random numbers.

The ability to generate random numbers, especially when combined with seeds for reproducibility, has a wide range of applications in computer science, simulations, gaming, statistics, cryptography and more.

Note: math.random() does not truly generate random numbers since a seed algorithm is used for an initial value.

Syntax

The random() method can be called with or a without a number using the following syntax:

math.random(x) -- Returns a random number between 1 and x.
math.random(x, y) -- Returns a random number between x and y.

• Parameters are optional for this method. If a number is not specified, a random number between 0 and 1 will be generated.

Example 1

The following example shows the usage of math.random() without a parameter:

print(math.random())

Copy to clipboard
Copy to clipboard

The output will be similar to the following:

0.78322180675329

Copy to clipboard
Copy to clipboard

Example 2

The following example shows the usage of math.random() with parameters:

print(math.random(7))
print(math.random(10, 15))

Copy to clipboard
Copy to clipboard

This will result in an output similar to the following:

5
12

Copy to clipboard
Copy to clipboard

Example 3

The following example shows the usage of math.random() in conjunction with math.randomseed() function:

math.randomseed(7)

print(math.random())
print(math.random())
print(math.random())

Copy to clipboard
Copy to clipboard

This will result in the following output:

0.77898184896709
0.38808095006413
0.74830981146053

Copy to clipboard
Copy to clipboard

Note: Keep in mind that math.randomseed() will always generate a reproducible random sequence.