npsdr                   A unified Principal sufficient dimension
                        reduction method via kernel trick
npsdr_x                 Reconstruct the estimated sufficient predictors
                        for a given data matrix
plot.npsdr              Scatter plot with sufficient predictors from
                        npsdr() function
plot.psdr               Scatter plot with sufficient predictors from
                        psdr() function
psdr                    Unified linear principal sufficient dimension
                        reduction methods
psdr_bic                Order estimation via BIC-type criterion
rtpsdr                  Real time sufficient dimension reduction
                        through principal least squares SVM
