This is overly verbose, but that's okay. Basically I'm making a copy of the array, iterating over the original array $#array times, and removing the randomly selected element from the copy on each iteration.

That means that each element is used only once and that the resulting array is basically a randomized version of the input array. 

#!/usr/bin/perl

@arr=("1","2","3","4");
@sub=@arr;
foreach (@arr){
  $slot = int(rand(@sub));
  ($new) = splice(@sub,$slot,1);
  push(@newarr,$new);
}

foreach (@newarr){
print "$_\n";
}

[download]
And then scrunch up that code a little: 
$hold=@arr;
foreach (0...$hold){
  push(@newarr, splice(@arr,int(rand(@arr)),1));
}

[download]
Still seems inelegant though . . . hmmmm.
-oakbox

In reply to Re: random index in array - no duplicates by oakbox
in thread random index in array - no duplicates by emilford

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