align_pcdirs            Obtain PC directions with centered warping
                        functions
center_warping_funs     Center warping functions
compute_pfi             Compute permutation feature importance (PFI)
plot_pc_diffs           Plot principal component directions
plot_pc_directions      Plot principal component directions
prep_testing_data       Align test data and apply fPCA using elastic
                        method applied to training data
prep_training_data      Align training data and apply a method of
                        elastic fPCA
shifted_peaks           "Shifted Peaks" Simulated Dataset
simulate_functions      Simulate example functional data
