PlotVsLTime.R

#'Plot a score along the forecast time with its confidence interval
#'
#'Plot the correlation (\code{Corr()}), the root mean square error 
#'(\code{RMS()}) between the forecast values and their observational 
#'counterpart, the slope of their trend (\code{Trend()}), the 
#'InterQuartile range, maximum-mininum, standard deviation or median absolute 
#'Deviation of the ensemble members (\code{Spread()}), or the ratio between 
#'the ensemble spread and the RMSE of the ensemble mean (\code{RatioSDRMS()}) 
#'along the forecast time for all the input experiments on the same figure 
#'with their confidence intervals.
#'
#'@param var Matrix containing any Prediction Score with dimensions:\cr
#'  (nexp/nmod, 3/4 ,nltime)\cr
#'  or (nexp/nmod, nobs, 3/4 ,nltime).
#'@param toptitle Main title, optional.
#'@param ytitle Title of Y-axis, optional.
#'@param monini Starting month between 1 and 12. Default = 1.
#'@param freq 1 = yearly, 12 = monthly, 4 = seasonal, ... Default = 12.
#'@param nticks Number of ticks and labels on the x-axis, optional.
#'@param limits c(lower limit, upper limit): limits of the Y-axis, optional.
#'@param listexp List of experiment names, optional.
#'@param listobs List of observation names, optional.
#'@param biglab TRUE/FALSE for presentation/paper plot. Default = FALSE.
#'@param hlines c(a,b, ..) Add horizontal black lines at Y-positions a,b, ...\cr
#'  Default = NULL.
#'@param leg TRUE/FALSE if legend should be added or not to the plot. 
#'  Default = TRUE.
#'@param siglev TRUE/FALSE if significance level should replace confidence 
#'  interval.\cr
#'  Default = FALSE.
#'@param sizetit Multiplicative factor to change title size, optional.
#'@param show_conf TRUE/FALSE to show/not confidence intervals for input 
#'  variables.
#'@param fileout Name of output file. Extensions allowed: eps/ps, jpeg, png, 
#'  pdf, bmp and tiff. The default value is NULL.
#'@param width File width, in the units specified in the parameter size_units 
#'  (inches by default). Takes 8 by default.
#'@param height File height, in the units specified in the parameter 
#'  size_units (inches by default). Takes 5 by default.
#'@param size_units Units of the size of the device (file or window) to plot 
#'  in. Inches ('in') by default. See ?Devices and the creator function of the 
#'  corresponding device.
#'@param res Resolution of the device (file or window) to plot in. See 
#'  ?Devices and the creator function of the corresponding device.
#'@param ... Arguments to be passed to the method. Only accepts the following
#'  graphical parameters:\cr
#'  adj ann ask bg bty cex.sub cin col.axis col.lab col.main col.sub cra crt 
#'  csi cxy err family fg fig font font.axis font.lab font.main font.sub 
#'  lheight ljoin lmitre mar mex mfcol mfrow mfg mkh oma omd omi page pch plt 
#'  smo srt tck tcl usr xaxp xaxs xaxt xlog xpd yaxp yaxs yaxt ylbias ylog \cr
#'  For more information about the parameters see `par`.
#'
#'@details
#'Examples of input:\cr
#'Model and observed output from \code{Load()} then \code{Clim()} then 
#'\code{Ano()} then \code{Smoothing()}:\cr
#'(nmod, nmemb, nsdate, nltime) and (nobs, nmemb, nsdate, nltime)\cr
#'then averaged over the members\cr
#'\code{Mean1Dim(var_exp/var_obs, posdim = 2)}:\cr
#'(nmod, nsdate, nltime) and (nobs, nsdate, nltime)\cr
#'then passed through\cr
#'  \code{Corr(exp, obs, posloop = 1, poscor = 2)} or\cr
#'  \code{RMS(exp, obs, posloop = 1, posRMS = 2)}:\cr
#'  (nmod, nobs, 3, nltime)\cr
#'would plot the correlations or RMS between each exp & each obs as a function 
#'of the forecast time.
#'
#'@examples
#'# Load sample data as in Load() example:
#'example(Load)
#'clim <- Clim(sampleData$mod, sampleData$obs)
#'ano_exp <- Ano(sampleData$mod, clim$clim_exp)
#'ano_obs <- Ano(sampleData$obs, clim$clim_obs)
#'runmean_months <- 12
#'smooth_ano_exp <- Smoothing(data = ano_exp, runmeanlen = runmean_months)
#'smooth_ano_obs <- Smoothing(data = ano_obs, runmeanlen = runmean_months)
#'dim_to_mean <- 'member'  # mean along members
#'required_complete_row <- 'ftime'  # discard startdates for which there are NA leadtimes
#'leadtimes_per_startdate <- 60
#'corr <- Corr(MeanDims(smooth_ano_exp, dim_to_mean), 
#'             MeanDims(smooth_ano_obs, dim_to_mean), 
#'             comp_dim = required_complete_row, 
#'             limits = c(ceiling((runmean_months + 1) / 2), 
#'                        leadtimes_per_startdate - floor(runmean_months / 2)))
#'# Combine corr results for plotting
#'corr_combine <- abind::abind(corr$conf.lower, corr$corr, corr$conf.upper, corr$p.val, along = 0)
#'corr_combine <- Reorder(corr_combine, c(2, 3, 1, 4))
#'\donttest{
#'PlotVsLTime(corr_combine, toptitle = "correlations", ytitle = "correlation", 
#'            monini = 11, limits = c(-1, 2), listexp = c('CMIP5 IC3'), 
#'            listobs = c('ERSST'), biglab = FALSE, hlines = c(-1, 0, 1))
#'  }
#'
#'@importFrom grDevices dev.cur dev.new dev.off
#'@importFrom stats ts
#'@export
PlotVsLTime <- function(var, toptitle = '', ytitle = '', monini = 1, freq = 12, 
               nticks = NULL, limits = NULL, 
               listexp = c('exp1', 'exp2', 'exp3'), 
               listobs = c('obs1', 'obs2', 'obs3'), biglab = FALSE, hlines = NULL, 
               leg = TRUE, siglev = FALSE, sizetit = 1, show_conf = TRUE,
               fileout = NULL, 
               width = 8, height = 5, size_units = 'in', res = 100, ...) {
  # Process the user graphical parameters that may be passed in the call
  ## Graphical parameters to exclude
  excludedArgs <- c("cex", "cex.axis", "cex.lab", "cex.main", "col", "fin", "lab", "las", "lend", "lty", "lwd", "mai", "mgp", "new", "pin", "ps", "pty")
  userArgs <- .FilterUserGraphicArgs(excludedArgs, ...)

  # If there is any filenames to store the graphics, process them
  # to select the right device 
  if (!is.null(fileout)) {
    deviceInfo <- .SelectDevice(fileout = fileout, width = width, height = height, units = size_units, res = res)
    saveToFile <- deviceInfo$fun
    fileout <- deviceInfo$files
  }

  #
  #  Get some arguments
  # ~~~~~~~~~~~~~~~~~~~~
  #
  if (length(dim(var)) == 3) {
    var <- InsertDim(var, posdim = 2, lendim = 1)
  } else if (length(dim(var)) != 4) {
    stop("Parameter 'var' should have 3 or 4 dimensions: c(n. exp[, n. obs], 3/4, n. lead-times)")
  }
  nleadtime <- dim(var)[4]
  nexp <- dim(var)[1]
  nobs <- dim(var)[2]
  if (is.null(limits) == TRUE) {
	if (all(is.na(var > 0))) {
      ll <- ul <- 0
	} else {
      ll <- min(var, na.rm = TRUE)
      ul <- max(var, na.rm = TRUE)
    }
    if (biglab) {
      ul <- ul + 0.4 * (ul - ll)
    } else {
      ul <- ul + 0.3 * (ul - ll)
    }
  } else {
    ll <- limits[1]
    ul <- limits[2]
  }
  lastyear <- (monini + (nleadtime - 1) * 12 / freq - 1) %/% 12
  lastmonth <- (monini + (nleadtime - 1) * 12 / freq - 1) %% 12 + 1
  empty_ts <- ts(start = c(0000, (monini - 1) %/% (12 / freq) + 1), 
                 end = c(lastyear, (lastmonth - 1) %/% (12 / freq) + 1),
                 frequency = freq)
  empty <- array(dim = length(empty_ts))
  #
  #  Define some plot parameters
  # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  #
  if (is.null(nticks)) {
    if (biglab) {
      nticks <- 5
    } else {
      nticks <- 10
    }
  }
  labind <- seq(1, nleadtime, max(nleadtime %/% nticks, 1))
  months <- c("Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep",
              "Oct", "Nov", "Dec")
  labyear <- ((labind - 1) * 12 / freq + monini - 1) %/% 12
  labmonth <- months[((labind - 1) * 12 / freq + monini -1 ) %% 12 + 1]
  for (jx in 1:length(labmonth)) {
    y2o3dig <- paste("0", as.character(labyear[jx]), sep = "")
    labmonth[jx] <- paste(labmonth[jx], "\nYr ", substr(y2o3dig, nchar(y2o3dig)
                    - 1, nchar(y2o3dig)), sep = "")
  }
  color <- c("red1", "dodgerblue1", "green1", "orange1", "lightblue1", 
             "deeppink1", "mediumpurple1", "lightgoldenrod1", "olivedrab1", 
             "mediumorchid1")
  type <- c(1, 3, 2, 4)
  thickness <- array(dim = c(4, 4))
  thickness[, 1] <- c(1, 2, 1, 1.5)
  thickness[, 2] <- c(8, 12, 8, 10)
  thickness[, 3] <- thickness[, 1]
  thickness[, 4] <- c(4, 6, 4, 5)
  if (siglev == TRUE) {
    lines <- c("n", "l", "n", "l")
  } else {
    lines <- c("l", "l", "l", "n")
  }
  #
  #  Define plot layout
  # ~~~~~~~~~~~~~~~~~~~~
  #

  # Open connection to graphical device
  if (!is.null(fileout)) {
    saveToFile(fileout)
  } else if (names(dev.cur()) == 'null device') {
    dev.new(units = size_units, res = res, width = width, height = height)
  }

  # Load the user parameters
  par(userArgs)
  
  if (biglab) {
    par(mai = c(1.25, 1.4, 0.5, 1), mgp = c(4, 2.5, 0))
    par(cex = 1.3, cex.lab = 2, cex.axis = 1.8)
    cexmain <- 2.2
    legsize <- 1.5
  } else {
    par(mai = c(1, 1.1, 0.5, 0), mgp = c(3, 1.8, 0))
    par(cex = 1.3, cex.lab = 1.5, cex.axis = 1.1)
    cexmain <- 1.5
    legsize <- 1
  }
  plot(empty, ylim = c(ll, ul), xlab = "Time (months)", ylab = ytitle, 
       main = toptitle, cex.main = cexmain*sizetit, axes = FALSE)
  axis(1, at = labind, labels = labmonth)
  axis(2)
  box()
  if (is.null(hlines) != TRUE) { 
    for (jy in 1:length(hlines)) {
      par(new = TRUE) 
      abline(h = hlines[jy])
    }
  }
  #
  #  Loop on experimental & observational data
  # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  #                
  legendnames <- array(dim = nobs * nexp)
  legendthick <- array(dim = nobs * nexp)
  legendsty <- array(dim = nobs * nexp)
  legendcol <- array(dim = nobs * nexp)
  ind <- 1
  if (show_conf == TRUE) {
    start_line <- dim(var)[3]
    end_line <- 1
  } else {
    start_line <- 2
    end_line <- 2
  }
  for (jt in seq(start_line, end_line, -1)) {
    ind <- 1
    for (jexp in 1:nexp) {
      for (jobs in 1:nobs) {
        par(new = TRUE)
        plot(var[jexp, jobs, jt, ], type = lines[jt], ylim = c(ll, ul), 
             col = color[jexp], lty = type[jobs], lwd = thickness[jobs, jt], 
             ylab = "", xlab = "", axes = FALSE)
        legendnames[ind] <- paste(listexp[jexp], 'vs', listobs[jobs])
        legendthick[ind] <- thickness[jobs, 1] * 3
        legendsty[ind] <- type[jobs]
        legendcol[ind] <- color[jexp]
        ind <- ind + 1
      }
    }
  }
  if (leg) {
    if (nobs == 1) {
      legendnames <- listexp[1:nexp]
    }  
    legend(1, ul, legendnames, lty = legendsty, lwd = legendthick,
           col = legendcol, cex = legsize)
  }
  
  # If the graphic was saved to file, close the connection with the device
  if(!is.null(fileout)) dev.off()
}