X-Git-Url: https://git.auder.net/doc/current/git-logo.png?a=blobdiff_plain;f=pkg%2FR%2FF_Neighbors.R;h=9d1e3fbb84c8fb6e451e1ba08a3c57b7d6906d1f;hb=4f3fdbb8e2ac4bd57a4e27539a58ef0e7ec2304c;hp=02536ebf164c9634c6bb7a6f23eeb3cf27fbbea9;hpb=638f27f4296727aff62b56643beb9f42aa5b57ef;p=talweg.git diff --git a/pkg/R/F_Neighbors.R b/pkg/R/F_Neighbors.R index 02536eb..9d1e3fb 100644 --- a/pkg/R/F_Neighbors.R +++ b/pkg/R/F_Neighbors.R @@ -1,27 +1,23 @@ #' Neighbors Forecaster #' -#' Predict next serie as a weighted combination of "futures of the past" days, -#' where days in the past are chosen and weighted according to some similarity measures. +#' Predict next serie as a weighted combination of curves observed on "similar" days in +#' the past (and future if 'opera'=FALSE); the nature of the similarity is controlled by +#' the options 'simtype' and 'local' (see below). #' -#' The main method is \code{predictShape()}, taking arguments data, today, memory, -#' predict_from, horizon respectively for the dataset (object output of -#' \code{getData()}), the current index, the data depth (in days), the first predicted -#' hour and the last predicted hour. -#' In addition, optional arguments can be passed: +#' Optional arguments: #' \itemize{ -#' \item local : TRUE (default) to constrain neighbors to be "same days within same -#' season" -#' \item simtype : 'endo' for a similarity based on the series only, +#' \item local: TRUE (default) to constrain neighbors to be "same days in same season" +#' \item simtype: 'endo' for a similarity based on the series only, #' 'exo' for a similarity based on exogenous variables only, #' 'mix' for the product of 'endo' and 'exo', #' 'none' (default) to apply a simple average: no computed weights -#' \item window : A window for similarities computations; override cross-validation +#' \item window: A window for similarities computations; override cross-validation #' window estimation. #' } #' The method is summarized as follows: #' \enumerate{ -#' \item Determine N (=20) recent days without missing values, and followed by a -#' tomorrow also without missing values. +#' \item Determine N (=20) recent days without missing values, and preceded by a +#' curve also without missing values. #' \item Optimize the window parameters (if relevant) on the N chosen days. #' \item Considering the optimized window, compute the neighbors (with locality #' constraint or not), compute their similarities -- using a gaussian kernel if @@ -61,8 +57,8 @@ NeighborsForecaster = R6::R6Class("NeighborsForecaster", if (!opera) tdays = setdiff(tdays, today) #always exclude current day - # Shortcut if window is known - if (hasArg("window")) + # Shortcut if window is known or local==TRUE && simtype==none + if (hasArg("window") || (local && simtype=="none")) { return ( private$.predictShapeAux(data, tdays, today, predict_from, horizon, local, list(...)$window, simtype, opera, TRUE) ) @@ -129,8 +125,8 @@ NeighborsForecaster = R6::R6Class("NeighborsForecaster", if (local) { - # TODO: 60 == magic number - tdays = getSimilarDaysIndices(today, data, limit=60, same_season=TRUE, + # limit=Inf to not censor any day (TODO: finite limit? 60?) + tdays = getSimilarDaysIndices(today, data, limit=Inf, same_season=TRUE, days_in=tdays_cut, operational=opera) # if (length(tdays) <= 1) # return (NA) @@ -146,6 +142,13 @@ NeighborsForecaster = R6::R6Class("NeighborsForecaster", } return ( data$getSerie(tdays[1])[predict_from:horizon] ) } + max_neighbs = 10 #TODO: 12 = arbitrary number + if (length(tdays) > max_neighbs) + { + distances2 <- .computeDistsEndo(data, today, tdays, predict_from) + ordering <- order(distances2) + tdays <- tdays[ ordering[1:max_neighbs] ] + } } else tdays = tdays_cut #no conditioning @@ -156,19 +159,9 @@ NeighborsForecaster = R6::R6Class("NeighborsForecaster", window_endo = ifelse(simtype=="mix", window[1], window) # Distances from last observed day to selected days in the past + # TODO: redundant computation if local==TRUE distances2 <- .computeDistsEndo(data, today, tdays, predict_from) - if (local) - { - max_neighbs = 12 #TODO: 12 = arbitrary number - if (length(distances2) > max_neighbs) - { - ordering <- order(distances2) - tdays <- tdays[ ordering[1:max_neighbs] ] - distances2 <- distances2[ ordering[1:max_neighbs] ] - } - } - simils_endo <- .computeSimils(distances2, window_endo) } @@ -284,7 +277,8 @@ NeighborsForecaster = R6::R6Class("NeighborsForecaster", sapply(tdays, function(i) { delta = lastSerie - c(data$getSerie(i-1), data$getSerie(i)[if (predict_from>=2) 1:(predict_from-1) else c()]) - sqrt(mean(delta^2)) +# sqrt(mean(delta^2)) + sqrt(sum(delta^2)) }) }