Get last value from array of arrays

Question

arr = [[a,1], [b,3], [c,2]]

How can I convert the above array into this below:

[1,3,2]

Andrew Marshall · Accepted Answer · 2012-06-20 01:14:10Z

6

arr.map(&:last)  #=> [1,3,2]

this is equivalent to the longer

arr.map { |o| o.last }

answered Jun 20, 2012 at 1:14

Andrew Marshall

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Comments

shouya · Accepted Answer · 2012-06-20 01:13:53Z

3

Just simply arr.map(&:last).

answered Jun 20, 2012 at 1:13

shouya

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Todd A. Jacobs · Accepted Answer · 2012-06-20 01:15:19Z

3

Another, more explicit way to perform this operation is with Array#collect:

array = [['a', 1], ['b', 3], ['c', 2]]
array.collect { |subarray| subarray.last }

It just depends on what semantics you need to represent what you're doing.

answered Jun 20, 2012 at 1:15

Todd A. Jacobs

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Ray Toal · Accepted Answer · 2012-06-20 01:13:31Z

1

If each element is a 2-element array, then just like this

arr.map{|x,y| y}

answered Jun 20, 2012 at 1:13

Ray Toal

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