R help - Jul 2017 - Calculating cumulative lengths of hierarchical topology

Hello All,

I need to calculate cumulative lengths along a hierarchical network 
topology (it's a representation of a tree).  I can roll my own, but 
thought that there might be a package out there that would handle 
hierarchical network topology functions such as this nicely (and that 
might bring along other useful functions as well).  However, I haven't 
found one after searching.

I did find data.tree, which looks quite interesting, but it carries a 
large overhead that doesn't seem quite appropriate for the relatively 
simple structure I'm dealing with.

Could anyone point me to such a package if one does exist?

Thanks very much,
Allie


Example of the hierarchical topology:

      len parent_row daughter_row index_num
1 1.7053          0            2         1
2 1.1653          1            3         2
3 1.1980          2            4         3
4 1.1462          3            5         4
5 1.1346          4            6         5
6 1.1024          5            7         6
...