R/hexplot.R

In Radviz: Project Multidimensional Data in 2D Space

#' A hexplot function for Radviz objects
#' 
#' Plots the Dimensional Anchors and a hexplot-based density representation
#' of projected data points in a 2D space.
#' 
#' @param x a radviz object as produced by do.radviz
#' @param main [Optional] a title to the graph, displayed on top
#' @param nbins the number of equally spaced bins for the binning computation (see \link[ggplot2]{geom_hex}
#'          for details)
#' @param color if color is not \code{NULL} and corresponds to one of the channels
#'          in the \code{hexcols} slot of the Radviz object, cells will be colored
#'          using colors in the \code{hexcols} slot
#' @param label.color the color of springs for visualization
#' @param label.size the size of the anchors (see \href{https://ggplot2.tidyverse.org/articles/articles/faq-customising.html}{customizing ggplot2} for details on default value)
#' @param mincnt deprecated, see \code{\link[ggplot2]{stat_summary_hex}} instead
#' @param style deprecated, see \code{\link[ggplot2]{stat_summary_hex}} instead
#' 
#' @return the internal ggplot2 object plus added layers, allowing for extra geoms to be added
#' 
#' @example examples/example-do.radviz.R
#' @examples
#' hexplot(rv,color='Sepal.Length')
#' 
#' @importFrom ggplot2 aes_string scale_fill_gradient geom_hex stat_summary_hex 
#' @import hexbin
#' 
#' @author Yann Abraham
#' 
#' @export
hexplot <- function(x,
                    main=NULL,
                    nbins=30,
                    color=NULL,
                    label.color=NULL,
                    label.size=NULL,
                    mincnt,
                    style) {
  ## check for deprecated arguments
  if(!missing(mincnt))
    warning('mincnt is a deprecated argument, use plot(x)+stat_summary_hex() and custom aes() to change plot.',call. = FALSE)
  if(!missing(style))
    warning('style is a deprecated argument, use plot(x)+stat_summary_hex() and custom aes() to change plot.',call. = FALSE)
  
  ## plot
  p <- plot.radviz(x,
                   main = main,
                   label.color = label.color,
                   label.size = label.size)
  p <- p+
    scale_fill_gradient(low='grey90',high='dodgerblue4')
  
  if(is.null(color)) {
    slayer <- geom_hex(bins=nbins)
  } else {
    slayer <- stat_summary_hex(aes_string(z=color),
                               fun=median,
                               bins=nbins)
  }
  p$layers <- c(slayer,p$layers)
  return(p)
}