root_on_node()Direct entry point to root_on_node(); recommended for expert use only.
RootTree() checks that input is properly formatted and is recommended
for general use.
root_on_node(phy, outgroup)root_on_node() returns phy rooted on the specified node.
Minimally, a named list with entries edge and Nnode, in the
format of equivalent entries in a tree of class phylo. edge.length will
also be considered if supplied.
Integer specifying index of leaf or node to set as the outgroup.