demean-demedian         Removes measure of centrality from the series
diffx-rdiffx-ldiffx     Compute lagged differnces
dtrend                  Deterministic Trend
fill_linear             Fill with "linear approximation"
fill_locf               Fill with "Last Observation Carried Forward"
fill_nocb               Fill with "Next observation carried backwards"
fill_spline             Fill with "cubic spline interpolation"
filter_bk               Baxter-King Filter
filter_bw               Butterworth Filter
filter_cf               Christiano-Fitzgerald Filter
filter_hamilton         Hamilton Filter
filter_hp               Hodrick-Prescot Filter
filter_tr               Trigonometric regression Filter
gmean                   Geometric Mean value
leadx-lagx              Compute lagged or leading values
modex                   Mode value
out_iqr                 Detect outliers with Tukey's method
out_pt                  Detect outliers with Percentiles
out_score_z             Detect outliers with zscore
out_score_zrob          Detect outliers Iglewicz and Hoaglin (1993)
                        robust z-score method
out_threshold           Detect outliers with upper and lower threshold
out_winsorise           Winsorize
pow                     nth Power Transformation
pow_boxcox              Box-Cox Transformations
pow_manly               Manly(1971) Transformations
pow_tukey               Tukey Transformations Transformations
pow_yj                  Yeo and Johnson(2000) Transformations
rebase                  Change the base year
root                    nth Root Transformation
scale_range             Rescale
score                   Score transformation
select_lambda           Selecting lambda
skewness                Skewness/Kurtosis Value
std                     Standarization
