Convert Array to Array of Arrays

Question

I have an array like this one:

array = ['john', 'jennifer', 'kristen', 'ted']

I would like to convert it to an array of arrays of k elements.
For example, if k = 2 the result should be:

[['john', 'jennifer'], ['kristen', 'ted']]

Is it possible to do so in one line?

This is covered in the documentation for Enumerable. It's a really good habit to read through a language's documentation a couple times to become familiar with what's available. Each time through you'll learn more. — the Tin Man
– the Tin Man, Commented Feb 29, 2016 at 21:03

Stefan · Accepted Answer · 2016-02-29 13:53:47Z

18

array.each_slice(2).to_a
#=> [["john", "jennifer"], ["kristen", "ted"]]

Stefan

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answered Feb 29, 2016 at 13:52

eugen

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1 Comment

@Stefan, thank you - I need to learn to link to the API docs.

Bobby Matson · Accepted Answer · 2016-02-29 14:52:55Z

3

If you want to create two arrays from one with a predicate (an expression which evaluates to either true or false), I would recommend partition

array.partition{ |name| name[0] == 'j' }
#=> [["john", "jennifer"], ["kristen", "ted"]]

answered Feb 29, 2016 at 14:52

Bobby Matson

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