Label R dendrogram branches with correct group number

Question

I am trying to draw a dendrogram so that the labels on the branches match the group number from my cluster analysis. Currently the branches are simply labelled from left to right in the order that they appear, not the actual group number. Here is my current R code and resulting dendrogram:

dst <- dist(Model_Results,method="binary") 
hca <- hclust(dst)
clust <- cutree(hca,k=40)
dend <-as.dendrogram(hca)
library(dendextend)
dend1 <- color_branches(dend, k = 40, groupLabels = TRUE)
plot(dend1)

How can I change the labels to match to my actual group number?

Answer 1

I think I finally managed to figure it out...

dst <- dist(Model_Results,method="binary") 
hca <- hclust(dst)
clust <- cutree(hca,k=40)
dend <-as.dendrogram(hca)
library(dendextend)
clust.cutree <- dendextend:::cutree(dend, k=40, order_clusters_as_data = FALSE)
idx <- order(as.numeric(names(clust.cutree)))
clust.cutree <- clust.cutree[idx]
tbl <- table(clust, clust.cutree)
lbls <- apply(tbl,2,which.max)
dend1 <- color_branches(dend, k = 40, groupLabels = lbls)
plot(dend1)