pkg/R/F_Average.R

   1 #' Average Forecaster
   2 #'
   3 #' Pointwise average of all the series of the same day of week in the past.
   4 #'
   5 #' For example, if the current day (argument "today") is a tuesday, then all series
   6 #' corresponding to wednesdays in the past (until the beginning or memory limit) are
   7 #' averaged to provide a smooth prediction. This forecast will most of the time be wrong,
   8 #' but will also look plausible enough.
   9 #'
  10 #' @docType class
  11 #' @format R6 class, inherits Forecaster
  12 #' @alias F_Average
  13 #'
  14 AverageForecaster = R6::R6Class("AverageForecaster",
  15     inherit = Forecaster,
  16
  17     public = list(
  18         predictShape = function(data, today, memory, horizon, ...)
  19         {
  20             avg = rep(0., horizon)
  21             first_day = max(1, today-memory)
  22             index = today-7 + 1
  23             nb_no_na_series = 0
  24             repeat
  25             {
  26                 {
  27                     serie_on_horizon = data$getCenteredSerie(index)[1:horizon]
  28                     index = index - 7
  29                 };
  30                 if (!any(is.na(serie_on_horizon)))
  31                 {
  32                     avg = avg + serie_on_horizon
  33                     nb_no_na_series = nb_no_na_series + 1
  34                 };
  35                 if (index < first_day)
  36                     break
  37             }
  38             avg / nb_no_na_series
  39         }
  40     )
  41 )