Interesting problem and discussion. I have little to add to what has already been said, but wanted to note that a solution to the problem of finding the index of the minimum in an array is conveniently implemented in Perl Data Language (PDL) with the minimum_ind function.

From the manual:

Module  PDL::Ufunc
  minimum_ind
      Signature: (a(n); indx [o] c())

    Like minimum but returns the index rather than the value

    Output is set bad if all elements of the input are bad, otherwise 
+the
    bad flag is cleared for the output piddle.
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So, in principle, assumming you already have an array @array you could do:

use PDL;
my $piddle = pdl @array;
my $index_minimum = minimum_ind $piddle;
say $index_minimum;
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You could try to reduce your problem so you can use a minimum_ind approach, for example, if you have negative numbers you could convert them to NaN or take abs and make them positive, whatever is important or relevant in your context.