ruby multidimension array sorting

Question

I have an array like this

arr = [[24,4], [44,5],[67,1], [30, 2], [67, 2]]

If i am using arr.sort{|a,b| b[0]<=>a[0]} i get this result

[[67,1], [67, 2], [44,5], [30, 2], [24,4]] -  #[value, id]

How to sort again the array to achieve this result

[[67,2], [67, 1], [44,5], [30, 2], [24,4]] -  #[value, id]

If there are same values, then the sort should happen on id descending .

thanks

Marc-André Lafortune · Accepted Answer · 2012-06-09 15:34:37Z

4

Why not take the simple and clear route:

arr.sort.reverse
# => [[67, 2], [67, 1], [44, 5], [30, 2], [24, 4]]

answered Jun 9, 2012 at 15:34

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Comments

tokland · Accepted Answer · 2012-06-09 12:29:49Z

3

It's better to use Enumerable#sort_by:

arr = [[24,4], [44,5],[67,1], [30, 2], [67, 2]]
arr.sort_by { |x, y| [-x, -y] }
#=> [[67, 2], [67, 1], [44, 5], [30, 2], [24, 4]]

answered Jun 9, 2012 at 12:29

tokland

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thanks tokland, is there any method to get results only for value > 50 from arr ?

use select. You should check the docs of Array and Enumerable.