class Array

Public Instance Methods

sample(n = nil) click to toggle source

# File lib/extensions/array.rb, line 3
def sample(n = nil)
  #based on code from https://github.com/marcandre/backports
  size = self.length
  return self[Kernel.rand(size)] if n.nil?

  n = n.to_int
  raise ArgumentError, "negative array size" if n < 0

  n = size if n > size

  result = Array.new(self)
  n.times do |i|
    r = i + Kernel.rand(size - i)
    result[i], result[r] = result[r], result[i]
  end
  result[n..size] = []
  result
end