This is a question from
ggtree user. In
phytools, it’s easy to label edge using the
set.seed(1) tr = rtree(30) library(ape) plot(tr, main="ape") edgelabels()
I don’t see any necessity to label edge numbers, as they are meaningless. The number is labeled as the row index of
tr$edge, and edge can be uniquely mapped to child node. If we need to relate something to edge, we can relate them to corresponding child node. Node is a central hub in tree annotation in
To label edge number, we can also attach the edge number to node and then label them as a node attribute.
library(ggtree) p = ggtree(tr, ladderize=F) + geom_tiplab() + ggtitle("ggtree") edge=data.frame(tr$edge, edge_num=1:nrow(tr$edge)) colnames(edge)=c("parent", "node", "edge_num") p %<+% edge + geom_label(aes(x=branch, label=edge_num))