Default

Common
JVM
JS
Native
1.0
companion object Default : Random , Serializable
(source)

The default random number generator.

On JVM this generator is thread-safe, its methods can be invoked from multiple threads.

import kotlin.math.sin
import kotlin.random.Random
import kotlin.test.assertTrue

fun main(args: Array<String>) {
//sampleStart
val randomValues = List(10) { Random.nextInt(0, 100) }
// prints new sequence every time
println(randomValues)

val nextValues = List(10) { Random.nextInt(0, 100) }
println(nextValues)
println("randomValues != nextValues is ${randomValues != nextValues}") // true
//sampleEnd
}

Companion Object Functions

Common
JVM
JS
Native
1.0

nextBits

Gets the next random bitCount number of bits.

fun nextBits ( bitCount : Int ) : Int
Common
JVM
JS
Native
1.0

nextBoolean

Gets the next random Boolean value.

fun nextBoolean ( ) : Boolean
Common
JVM
JS
Native
1.0

nextBytes

Fills the specified byte array with random bytes and returns it.

fun nextBytes ( array : ByteArray ) : ByteArray

Creates a byte array of the specified size , filled with random bytes.

fun nextBytes ( size : Int ) : ByteArray

Fills a subrange of the specified byte array starting from fromIndex inclusive and ending toIndex exclusive with random bytes.

fun nextBytes (
array : ByteArray ,
fromIndex : Int ,
toIndex : Int
) : ByteArray
Common
JVM
JS
Native
1.0

nextDouble

Gets the next random Double value uniformly distributed between 0 (inclusive) and 1 (exclusive).

fun nextDouble ( ) : Double

Gets the next random non-negative Double from the random number generator less than the specified until bound.

fun nextDouble ( until : Double ) : Double

Gets the next random Double from the random number generator in the specified range.

fun nextDouble ( from : Double , until : Double ) : Double
Common
JVM
JS
Native
1.0

nextFloat

Gets the next random Float value uniformly distributed between 0 (inclusive) and 1 (exclusive).

fun nextFloat ( ) : Float
Common
JVM
JS
Native
1.0

nextInt

Gets the next random Int from the random number generator.

fun nextInt ( ) : Int

Gets the next random non-negative Int from the random number generator less than the specified until bound.

fun nextInt ( until : Int ) : Int

Gets the next random Int from the random number generator in the specified range.

fun nextInt ( from : Int , until : Int ) : Int
Common
JVM
JS
Native
1.0

nextLong

Gets the next random Long from the random number generator.

fun nextLong ( ) : Long

Gets the next random non-negative Long from the random number generator less than the specified until bound.

fun nextLong ( until : Long ) : Long

Gets the next random Long from the random number generator in the specified range.

fun nextLong ( from : Long , until : Long ) : Long