You sure its not taking the sqrt of the memory address of the array? 
$a = $b = ["abc",123];
print "\$a is $a\n";
$a =~ s/\D+//;
print "The decimal value of the address of the array  is ",hex($a);
print "\n";
print sqrt(hex($a)),"==", sqrt($b),"\n";

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In reply to Re^2: sqrt string? by Anonymous Monk
in thread Static typing is mostly a waste of time by johnnywang

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