use strict;
use warnings;
use Math::Vector::Real;
 
my $v = V(2,-3,6); # Your example vector

print "Norm  = ", Normalize ($v),"\n";
print "Versor= ", $v->versor(),"\n";

sub Normalize{
  my ($v) = @_; # parameter is a single vector
  
  my $result = $v->div ( $v->abs() );
       # abs of vector (x,y,z)  = sqrt(x**2 + y**2 + z**2)
  return $result;
}