pkg/R/F_Persistence.R

   1 #' Persistence Forecaster
   2 #'
   3 #' Look for the most recent similar day in the past, and return its corresponding curve.
   4 #' "Similar day" means "same day in the week".
   5 #'
   6 #' @format R6 class, inherits Forecaster
   7 #' @alias F_Persistence
   8 #'
   9 PersistenceForecaster = R6::R6Class("PersistenceForecaster",
  10     inherit = Forecaster,
  11
  12     public = list(
  13         predictShape = function(data, today, memory, horizon, ...)
  14         {
  15             # Return centered last (similar) day curve, avoiding NAs until memory is run
  16             first_day = max(1, today-memory)
  17             same_day = ifelse(hasArg("same_day"), list(...)$same_day, TRUE)
  18             # If 'same_day', get the last known future of similar day: -7 + 1 == -6
  19             index = today - ifelse(same_day,6,0)
  20             repeat
  21             {
  22                 {
  23                     last_serie = data$getCenteredSerie(index)[1:horizon]
  24                     index = index - ifelse(same_day,7,1)
  25                 };
  26                 if (!any(is.na(last_serie)))
  27                     return (last_serie);
  28                 if (index < first_day)
  29                     return (NA)
  30             }
  31         }
  32     )
  33 )