NewKnnClassifier returns a new classifier.

NewKnnRegressor mints a new classifier.

ReloadKNNClassifier reloads a KNNClassifier when it's the only thing in an output file.

A KNNClassifier consists of a data matrix, associated labels in the same order as the matrix, searching algorithm, and a distance function.

A KNNRegressor consists of a data matrix, associated result variables in the same order as the matrix, and a name.