How to sort an array based off another array which holds the indexes [duplicate]

Question

I have array a that holds the position of what the array b should.

a = [3, 2, 0, 1]
b = ["hello", "hi", 2332, "ben"]

I want to sort b so that it will become

["ben", 2332, "hello", "hi"]

where it get's its index from array a.

steenslag · Accepted Answer · 2017-04-17 18:08:43Z

8

b = ["hello", "hi", 2332, "ben"]
a = [3, 2, 0, 1]

p b.values_at(*a)  # => ["ben", 2332, "hello", "hi"]

answered Apr 17, 2017 at 18:08

steenslag

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1 Comment

Yes, thank you! I was trying to do it using sort, index and map but it didn't work out for me. Thanks!

Yevgeniy Anfilofyev · Accepted Answer · 2017-04-17 18:33:30Z

1

If you would like to use map here is how to:

b = ["hello", "hi", 2332, "ben"]
a = [3, 2, 0, 1]
a.map{|i| b[i]}  # => ["ben", 2332, "hello", "hi"]

answered Apr 17, 2017 at 18:33

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