a vector of classifications; this must be a vector of characters,
integers, numerics, or a factor, but not a list.
b
a vector of classifications
Details
In information theory, purity is an external evaluation criterion of cluster
quality. It is the percent of the total number of objects (data points) that
were classified in the range of [0,1]. Because we lack a ground truth
partition, a harmonic mean is calculated, where we consider partition a to be
the ground truth and then consider partition b to be the ground truth.