wren/doc/site/modules/random/random.markdown

^title Random Class

A simple, fast pseudo-random number generator. Internally, it uses the well equidistributed long-period linear PRNG (WELL512a).

Each instance of the class generates a sequence of randomly distributed numbers based on the internal state of the object. The state is initialized from a seed. Two instances with the same seed generate the exact same sequence of numbers.

It must be imported from the random module:

:::wren
import "random" for Random

Constructors

Random.new()

Creates a new generator whose state is seeded based on the current time.

:::wren
var random = Random.new()

Random.new(seed)

Creates a new generator initialized with [seed]. The seed can either be a number, or a non-empty sequence of numbers. If the sequnce has more than 16 elements, only the first 16 are used. If it has fewer, the elements are cycled to generate 16 seed values.

:::wren
Random.new(12345)
Random.new("appleseed".codePoints)

Methods

float()

Returns a floating point value between 0.0 and 1.0, including 0.0, but excluding 1.0.

:::wren
var random = Random.new(12345)
System.print(random.float()) //> 0.53178795980617
System.print(random.float()) //> 0.20180515043262
System.print(random.float()) //> 0.43371948658705

float(end)

Returns a floating point value between 0.0 and end, including 0.0 but excluding end.

:::wren
var random = Random.new(12345)
System.print(random.float(0))     //> 0
System.print(random.float(100))   //> 20.180515043262
System.print(random.float(-100))  //> -43.371948658705

float(start, end)

Returns a floating point value between start and end, including start but excluding end.

:::wren
var random = Random.new(12345)
System.print(random.float(3, 4))    //> 3.5317879598062
System.print(random.float(-10, 10)) //> -5.9638969913476
System.print(random.float(-4, 2))   //> -1.3976830804777

int(end)

Returns an integer between 0 and end, including 0 but excluding end.

:::wren
var random = Random.new(12345)
System.print(random.int(1))    //> 0
System.print(random.int(10))   //> 2
System.print(random.int(-50))  //> -22

int(start, end)

Returns an integer between start and end, including start but excluding end.

:::wren
var random = Random.new(12345)
System.print(random.int(3, 4))    //> 3
System.print(random.int(-10, 10)) //> -6
System.print(random.int(-4, 2))   //> -2