R/get_color_gradient.R

In pageRank: Temporal and Multiplex PageRank for Gene Regulatory Network Analysis

#' Generate Color Gradient
#'
#' Generate color gradient for, e.g. gene expression.
#'
#' @param x (numeric) Vector based on which color gradient is generated.
#' 
#' @param col (character) Color vector.
#' 
#' @param breaks (numeric) A set of breakpoints for the colors. Must be the same
#' length of col.
#' 
#' @return (character) Colors.
#'
#' @examples
#' get_color_gradient(-2:2)
#'
#' @author DING, HONGXU (hd2326@columbia.edu)
#' 
#' @import grDevices
#'
#' @export

get_color_gradient <- function (x,
                                col=colorRampPalette(c("Blue", "Red"))(100),
                                breaks=seq(-2, 2, length.out=100)){
    color <- NULL
    if (length(col)  == length(breaks))
        color <- col[unlist(lapply(x, function(xx, breaks){
            which.min(abs(xx - breaks))}, breaks = breaks))]
    else message("col and breaks should be the same length")
    return(color)}