Generate Random value from a collection in ruby

Question

To make it simple, i have a list of Products.

Now i want to create a method and will generate me a random Product each time.

How do i achieve that.

score 7 · Answer 1 · answered Sep 15 '11 at 14:12

7

assuming you have an array products of Products, then you can select a random Product by the following code:

randon_product = products.sample

answered Sep 15 '11 at 14:12

ennuikiller

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score 2 · Answer 2 · answered Sep 15 '11 at 15:47

2

In 1.9 you have [].sample and in 1.8 you have [].choice. There is a gem called backports that harmonizes this and other differences, or you could do it yourself like this:

class Array
  def sample
    choice
  end
end unless Array.method_defined? :sample

answered Sep 15 '11 at 15:47

DigitalRoss

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+1 for showing off the do-it-yourself technique. Very useful. – Ray Toal Sep 15 '11 at 16:18

score 1 · Answer 3 · answered Sep 15 '11 at 14:14

1

In Ruby 1.8, the simplest way is probably Array#choice

irb(main):005:0> 5.times {puts (1..100).to_a.choice} 
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=> 5
irb(main):006:0> [5,3,234,234,3,2,2,2].choice
=> 3

EDIT In Ruby 1.9 it is called sample, not choice.

answered Sep 15 '11 at 14:14

Ray Toal

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See DigitalRoss's answer for a nice way to allow the use of `sample` in all Ruby versions. [Here's the change log for Ruby 1.9.1 showing that choice was removed](http://svn.ruby-lang.org/repos/ruby/branches/ruby_1_9_1/NEWS) – Ray Toal Sep 15 '11 at 16:24

score 0 · Answer 4 · answered Sep 15 '11 at 15:13

0

array = [product1, product2, product3]

puts array[rand(array.size)]

answered Sep 15 '11 at 15:13

evfwcqcg

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Generate Random value from a collection in ruby

4 Answers4