Hi, I am trying to find an easy way to implement distance among trees, as in Tree::DAG_Node. I have found some info about Robinson-Foulds distance, but only in the shape of code, and I don't know exactly if it is what I'm looking for. Meanwhile, I make do with this:

use Tree::DAG_Node;
use String::Approx qw(adist);
my $lol1=[['a','b'],['c','d'],['e']];
my $lol2=[['a','b','c'],['d'],['e']];
my $tree1 = Tree::DAG_Node->lol_to_tree( $lol1 );
my $tree2 = Tree::DAG_Node->lol_to_tree( $lol2 );
my $str1 = $tree1->tree_to_lol_notation();
my $str2 = $tree2->tree_to_lol_notation();
my $dist = adist( $str1, $str2 );
print "Distance between $str1 and $str2 is $dist\n";
[download]

But it's not exactly what I'm looking for, since changing a node from one subtree to another would give distance=7 (or 4 in the case above). Can anybody help me? Pointers to RF distance definition anywhere? Thanks!

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