In [2]:

%classpath add mvn org.apache.commons commons-math3 3.6.1

In [3]:

import org.apache.commons.math3.random.RandomDataGenerator
import collection.JavaConverters._
val rng = new RandomDataGenerator()

Out[3]:

scala.collection.JavaConverters$@783d0556

RandomDataGenerator.nextInt ¶

Notice that the both of the endpoints are included, which is different from typcial Java conventions!!!

In [4]:

rng.nextInt(0, 2)

Out[4]:

In [5]:

rng.nextInt(0, 1)

Out[5]:

In [7]:

rng.nextInt(0, 1)

Out[7]:

RandomDataGenerator.nextPermutation ¶

In [3]:

rng.nextPermutation(5, 3)

Out[3]:

[4, 3, 0]

In [4]:

rng.nextPermutation(5, 3)

Out[4]:

[2, 3, 0]

In [14]:

val vec = Vector(10, 20, 30, 40, 50)

Out[14]:

[[10, 20, 30, 40, 50]]

In [19]:

rng.nextSample(vec.asJava, 3).mkString(" ")

Out[19]:

50 20 10

In [20]:

rng.nextSample(vec.asJava, 3).mkString(" ")

Out[20]:

50 30 40