How to find two elements that have smallest difference in an array?

Question

How do I find two elements in an array that have the smallest difference?

In other words, how to find two elements that have a the smallest standard deviation.

For instance, if I have an array like:

arr = [158,2,15,38,17,91]

the result would be 15 and 17.

[*Standard deviation*](https://en.wikipedia.org/wiki/Standard_deviation) is an indication of the difference with the mean, not the difference between two values in the data set. — trincot, Jul 15 '16 at 18:12
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score 8 · Accepted Answer · answered Jul 15 '16 at 18:18

8

I assume the question is, "for which two elements of the array is the absolute value of their difference minimum?".

arr.combination(2).min_by { |a,b| (a-b).abs }
  #=> [15, 17]

answered Jul 15 '16 at 18:18

Cary Swoveland

1 Answers1