ClassPP                 Projection Pursuit for Supervised
                        Classification
LDA.Tree                Find PP tree structure using LDA
PDA.Tree                Find PP tree structure using PDA
PP.Tree                 Find PP tree structure
PP.classify             Predict class for the test set and calculate
                        prediction error
PP.optimize             Find optimal projection by maximizing selected
                        PP index
PPindex.class           Calculate Projection Pursuit index
