Ruby: How to find the index of the minimum array element?

Question

Is there any way to rewrite this more elegant? I think, that it's a bad piece of code and should be refactored.

>> a = [2, 4, 10, 1, 13] => [2, 4, 10, 1, 13] >> index_of_minimal_value_in_array = a.index(a.min) => 3 

Answer 1

I believe this will traverse the array only once and is still easy to read:

numbers = [20, 30, 40, 50, 10]           # => [20, 30, 40, 50, 10] elem, idx = numbers.each_with_index.min  # => [10, 4] 

Answer 2

This traverses the array only once whereas ary.index(ary.min) would traverse it twice:

ary.each_with_index.inject(0){ |minidx, (v,i)| v < a[minidx] ? i : minidx }