Hi dear monks. i wrote following subroutine

sub versatility{
my(%site1)=@_;
my(%site2)=@_;

for (keys(%site1)) {
   if ($site2{$_}) {
     my $m=(@{$site1{$_}}[1]-@{$site2{$_}}[1]);
     my $n=(@{$site1{$_}}[0]-@{$site2{$_}}[0]);
     my $slope=$m/$n;
       print "velocity= $slope\n";

   }
}
}

[download]

but i have problem that says :cant use string [0,1] as an ARRAY refrence.i gave refrence as you see,but i dont know the reason for this error.please help me.

In reply to hash references by Anonymous Monk

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