As all algorithms are executed in linear time now, this is not as useful, but nevertheless an interesting feature. If you already have clustered data, this feature is great.
When using this, calculations are done per unique value.
Say you have a dataset of infant height, in centimeters.
That’s probably only going to be some 40 different values, but potentially millions of entries.
Using clusters, all that data is only processed as
O(millions). (I know that notation isn’t right, but you get my point).