Clustering methods

The clustering methods in scikit-learn have a nice congruent usage that, for the most part, matches the following pseudocode across all the algorithms:

### this is pseudocode. it will not execute ###
# import module and instantiate method object
from sklearn.cluster import Method
clus = Method(args*)

# fit to input data
clus.fit(X_input)

# get cluster assignments of X_input
X_assigned = clus.labels_

The rest of this chapter will cover some common methods used for data clustering. The following is a group of plots comparing different cluster methods and how they assign data points into groups: