@amoeba: The minor difference you see is because sklearn's iris dataset is not the same as R's or MATLAB's or
Wikipedia's for that matter. For example if you check the 38th row on MATLAB you will get:
4.9 3.6 1.4 0.1
which is the same as R's. The same row in Python is:
4.9 3.1 1.5 0.1
. Do not ask me why; I guess it's one of the cases sklearn is
special in it's own way.