censor_event            Censor of events
fx_h_time               Functions to help in time conversion
is_single_number        Confirm is a single number
s_exponential           Factory of SURVIVAL objects with Exponential
                        distributions
s_factory               Factory of objects of class SURVIVAL
s_gompertz              Factory of SURVIVAL objects with Gompertz
                        distributions
s_piecewise             Factory of SURVIVAL objects with Piecewise
                        Exponential distributions
s_weibull               Factory of SURVIVAL objects with Weibull
                        distributions
sfx                     Functions for SURVIVAL objects
