Urgle. While you pick a fast algorithm, your implementation is not efficient. There's no need to build @selection element by element, while popping off one element of of @population at the time. Just run $n iterations of Fisher-Yates loop, and return the last $n elements of the array. Furthermore, 
if ($swapper < $#population) {
    $population[$swapper] = $population[-1];
}

[download]
is less efficient than 
$population[$swapper] = $population[-1];

[download]
Sure, the if statement prevents a needless assignment, but the expected number of needless assignments is 
Σi=0$n 1/(@population - i)
which, while unbounded, grows very very slowly if the array to sample grows. OTOH, the number of compares done is linear with the size of the sample taken.

Abigail

In reply to Re: Select three random numbers between 1..10 by Abigail-II
in thread Select three random numbers between 1..10 by Perl_User

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