== K-means clustering == 

 You added the statement "Jenks natural breaks optimization: k-means applied to univariate data" to this article. 

 However, if I am not mistaken, the original use case of Lloyd was univariate, wasn't it? 

 This sounds as if k-means would not work with univariate data. I don't know much about Jenks, so maybe there are some other differences (does it sort the data first?) that make it faster for univariate data?