pkg/R/b_LinearAlgorithm.R

   1 #' @include b_Algorithm.R
   2
   3 #' @title Linear Algorithm
   4 #'
   5 #' @description Generic class to represent a linear algorithm.
   6 #' TODO: not needed in production environment; weights growing infinitely.
   7 #' Inherits \code{\link{Algorithm}}
   8 #'
   9 #' @field weights The matrix of weights (in rows) associated to each expert (in columns)
  10 #'
  11 LinearAlgorithm = setRefClass(
  12     Class = "LinearAlgorithm",
  13
  14     fields = c(
  15         weights = "matrix"
  16     ),
  17
  18     contains = "Algorithm",
  19
  20     methods = list(
  21         initialize = function(...)
  22         {
  23             callSuper(...)
  24             weights <<- matrix(nrow=0, ncol=ncol(data)-3)
  25         },
  26
  27         appendWeight = function(weight)
  28         {
  29             "Append the last computed weights to the weights matrix, for further plotting"
  30
  31             n = nrow(data)
  32             nx = n - nrow(subset(data, subset = (Date == data[n,"Date"])))
  33             x = data[(nx+1):n, !names(data) %in% c("Date","Measure","Station")]
  34             iy = getNoNAindices(x, 2)
  35
  36             completedWeight = rep(NA, ncol(x))
  37             completedWeight[iy] = weight
  38             weights <<- rbind(weights, completedWeight)
  39         },
  40
  41         plotWeights = function(station=1, start=1, ...)
  42         {
  43             "Plot the weights of each expert over time"
  44
  45             if (is.character(station))
  46                 station = match(station, stations)
  47
  48             #keep only full weights (1 to K)
  49             weights_ = weights[getNoNAindices(weights),]
  50             weights_ = weights_[start:nrow(weights_),]
  51
  52             yRange = range(weights_, na.rm=TRUE)
  53             K = ncol(weights_)
  54             cols = rainbow(K)
  55             par(mar=c(5,4.5,1,1), cex=1.5)
  56             for (i in 1:K)
  57             {
  58                 plot(weights_[,i], type="l", xaxt="n", ylim=yRange, col=cols[i], xlab="", ylab="",cex.axis=1.5, ...)
  59                 par(new=TRUE)
  60             }
  61             axis(side=1, at=seq(from=1,to=nrow(weights_),by=30), labels=seq(from=0,to=nrow(weights_),by=30) + start, cex.axis=1.5)
  62             title(xlab="Time",ylab="Weight", cex.lab=1.6)
  63         }
  64     )
  65 )