R/plotLegend.r

In geoelectrics: 3D-Visualization of Geoelectric Resistivity Measurement Profiles

#' Plots Legend
#'
#' Plots the legend for resistivity values.
#'
#' @param .Object either a single Profile or a ProfileSet.
#' @param legend.lab label of legend (default: expression(paste("Resistivity [", Omega, "]"))).
#' @param minData minimum value.
#' @param maxData maximum value.
#' @param breaks Break points in sorted order to indicate the intervals for assigning the colors.
#' Note that if there are nlevel colors there should be (nlevel+1) breakpoints.
#' If breaks is not specified (nlevel+1) equally spaced breaks are created where the first and last bin have their midpoints at the minimum and maximum values in z or at zlim.
#' @param lab.breaks number of breaks.
#' @param legend.line distance in units of character height (as in mtext) of the legend label from the color bar.
#' Make this larger if the label collides with the color axis labels.
#' @param nlevel number of color levels.
#' @param col vector of colors.
#' @param trafo transformation to be done on data (default: log).
#' For linear scale: function(x) x.
#' @param backtrafo back transformation to plot correct labels (default: exp).
#' For linear scale: function(x) x.
#' @param horizontal If false legend will be a vertical strip on the right side. If true (default) the legend strip will be along the bottom.
#' @param ... image.plot arguments.
#' @export
#' @seealso \code{\link{Profile-class}}, \code{\link{ProfileSet-class}},
#' \code{\link{plot3d}},
#' @examples
#' data(sinkhole)
#'
#' plotLegend(sinkhole)
#'
#' # for linear scale:
#' plotLegend(sinkhole@profiles[[1]],
#'            trafo=function(x) x,
#'            backtrafo=function(x) x,
#'            minData=100, maxData=50000)
setGeneric("plotLegend", function(.Object,
                                  legend.lab = expression(paste("Resistivity [", Omega, " m]")),
                                  minData = 0,
                                  maxData = 999999,
                                  breaks = NULL,
                                  legend.line = 2.2,
                                  nlevel = 18,
                                  lab.breaks = c(),
                                  horizontal = T,
                                  col = colors,
                                  trafo = log,
                                  backtrafo = exp,
                                  ...) {
  standardGeneric("plotLegend")
  if (length(lab.breaks) > 0)
    nlevel <- length(lab.breaks)
  if (length(lab.breaks) == 0)
    lab.breaks <- round(backtrafo(seq(
      trafo(minData),
      trafo(maxData),
      length.out = nlevel
    )))
  image.plot(
    legend.only = TRUE,
    add = F,
    breaks = breaks,
    zlim = c(minData, maxData),
    legend.line = legend.line,
    legend.lab = legend.lab,
    nlevel = nlevel,
    col = colorRampPalette(col)(nlevel - 1),
    lab.breaks = lab.breaks,
    horizontal = horizontal,
    ...
  )
})

#' @rdname plotLegend
#' @export
setMethod("plotLegend", signature(.Object = "ProfileSet"),
          function(.Object,
                   legend.lab,
                   minData = .Object@minData,
                   maxData = .Object@maxData) {
            
          })

#' @rdname plotLegend
#' @export
setMethod("plotLegend", signature(.Object = "Profile"),
          function(.Object,
                   legend.lab,
                   minData = .Object@processedData@minData,
                   maxData = .Object@processedData@maxData) {
            
          })