dummies                 Convert a N-category vector to a N-dimension
                        matrix
folds                   Generate a list of index for the n-fold
                        cross-validation
gen_latin               Generate random numbers of latin hypercube
                        sampling
gen_sobol               Generate sobol sequence
gen_unifm               Generate Uniform random numbers
logl                    Calculate the multiclass cross-entropy
pnn.fit                 Create a probabilistic neural network
pnn.imp                 Derive the importance rank of all predictors
                        used in the PNN
pnn.optmiz_logl         Optimize the optimal value of PNN smoothing
                        parameter based on the cross entropy
pnn.parpred             Calculate predicted probabilities of PNN by
                        using parallelism
pnn.pfi                 Derive the PFI rank of all predictors used in
                        the PNN
pnn.predict             Calculate a matrix of predicted probabilities
pnn.predone             Calculate the predicted probability for each
                        category of PNN
pnn.search_logl         Search for the optimal value of PNN smoothing
                        parameter based on the cross entropy
pnn.x_imp               Derive the importance of a predictor used in
                        the PNN
pnn.x_pfi               Derive the permutation feature importance of a
                        predictor used in the PNN
