Cluster Analysis in R: Elbow Method in K-means

Question

I'm implementing the elbow method to my data set using the R package fviz_nbclust. This method will calculate the total within sum square of each cluster by varying K from 1.....k. For example the elbow method suggest K=2. Say we have here two different results for K-means alone. Is there a way to find out which wss did the elbow method calculated? Is there a possible way to view which K-means result the elbow method used in clustered using K=2?

Answer 1

There might be more elegant methods but you could simply add out-of-scope assignment to your cluster function, e.g.:

l <- list()
f <- function(...) {
  km <- kmeans(...)
  l[[nrow(km$centers)]] <<- km
  km
}

fviz_nbclust(df, f, method = "wss", k.max = 10)

Then simply index l[[optimal nr of clusters]] to retrieve the model