R/showSignificance.R

In dcousin3/superb: Summary Plots with Adjusted Error Bars

######################################################################################
#' @title Annotate significance of results on plots
#'
#' @aliases showSignificance showVerticalSignificance showHorizontalSignificance
#'
#' @description showSignificance is used to add an annotation to 
#'    a ggplot in the form of a bracket with a text. The bracket 
#'    extends from x range (left, right) with a heigth of width. It is also possible
#'    to have the bracket and the text vertical when y is a range (bottom, top).
#'
#' @md
#'
#' @param x (a vector of 2 when horizontal) indicates the limits of the annotation;
#' @param y (a vector of 2 when vertical) the location of the annotation in the y direction
#' @param width height of the annotation; for negative width, the legs extends towards the bottom;
#' @param text (optional) string text to be display on the opposite side of width;
#' @param panel (optional) a list to identify in which panel to put the annotation;
#' @param segmentParams (optional) a list of directives that will be sent to the geom_segment items;
#' @param textParams (optional) a list of directives that will be sent to the geom_text item.
#'
#' @return adds an annotation in a ggplot
#'
#' @examples
#' # loading required libraries
#' library(superb)
#' library(ggplot2)
#' library(grid)
#' 
#' # making one random data set with three factors 2 x 3 x (3)
#' dta <- GRD(
#'     SubjectsPerGroup = 20,
#'     BSFactors = c("Group(2)","Age(3)"), 
#'     WSFactors = c("Moment(3)"),
#'     Population = list(mean = 75, stddev = 5),
#'     Effects   = list("Group" = slope(10) )
#' )
#' 
#' # making a two-factor plot and a three-factor plots (having panels)
#' plt2 <- superb(
#'         cbind(DV.1,DV.2,DV.3) ~ Group, 
#'         dta, 
#'         WSFactor = c("Moment(3)"),
#'         adjustments = list(purpose="difference"),
#'         factorOrder = c("Moment","Group")
#'     )
#' plt3 <- superb(
#'         cbind(DV.1,DV.2,DV.3) ~ Group + Age, 
#'         dta,
#'         WSFactor = c("Moment(3)"),
#'         adjustments = list(purpose="difference"),
#'         factorOrder = c("Moment","Group","Age")
#'     )
#' 
#' # lets decorate these plots a bit...
#' plt2 <- plt2 +  scale_fill_manual( name = "Group", 
#'         labels = c("Easy", "Hard"), 
#'         values = c("blue", "purple")) + 
#'   scale_colour_manual( name = "Group", 
#'         labels = c("Easy", "Hard"), 
#'         values = c("blue", "purple")) +
#'   coord_cartesian( ylim = c(50,100), xlim = c(0.5, 3.9) )
#' plt3 <- plt3 +  scale_fill_manual( name = "Group", 
#'         labels = c("Easy", "Hard"), 
#'         values = c("blue", "purple")) + 
#'   scale_colour_manual( name = "Group", 
#'         labels = c("Easy", "Hard"), 
#'         values = c("blue", "purple")) +
#'   coord_cartesian( ylim = c(50,105) )
#' 
#' # a very basic example
#' plt2 +  showSignificance( c(0.75, 1.25), 90, -1, "++1++")
#'
#' # the annotation can be vertical when y is a vector with bottom and top location:
#' plt2 + showSignificance( 3.75, c(70,80), -0.1, "++1++")
#' 
#' # an example with panels; the "panel" argument is used to identify on 
#' # which panel to put the annotation (or else they appear on all panels)
#' # and with arms of differing lengths, and one flat ending
#' plt3 + 
#'     showSignificance( c(0.75, 1.25), 90, -2.5,      "++1++", panel = list(Age= 1)) + 
#'     showSignificance( c(1.75, 2.25), 90, -2.5,      "++2++", panel = list(Age= 2)) + 
#'     showSignificance( c(0.75, 1.25), 90, c(-10,-5), "++3++", panel = list(Age= 3)) +
#'     showSignificance( c(2.00, 3.25), 95, -10,       "++4++", panel = list(Age= 3)) + 
#'     showSignificance( c(1.75, 2.25), 85, 0,                  panel = list(Age= 3))  
#' 
#' # here, we send additional directives to the annotations
#' plt3 + 
#'     showSignificance( c(0.75, 1.25), 90, -5,  "++1++", panel = list(Age= 1)) + 
#'     showSignificance( c(1.75, 2.25), 95, -10, "++2++", panel = list(Age = 2),
#'         textParams    = list(size = 3,              # smaller font
#'                             family  = "mono",       # courrier font
#'                             colour= "chartreuse3"   # dark green color
#'         ), 
#'         segmentParams = list(linewidth = 1.,             # thicker lines
#'                             arrow   = arrow(length = unit(0.2, "cm") ), # arrow heads
#'                             colour = "chartreuse3"  # dark green color as well
#'         )
#'     ) +
#'     showSignificance( c(1.75, 3.25), 95, -30, "++3++", panel = list(Age = 3),
#'         textParams    = list(size = 5,              # larger font
#'                             family  = "serif",      # times font
#'                             alpha = 0.3 ),          # transparent
#'         segmentParams = list(linewidth = 2., 
#'                             arrow   = arrow(length = unit(0.2, "cm") ), 
#'                             alpha = 0.3, 
#'                             lineend = "round"       # so that line end overlap nicely
#'         )
#'     )
#' 
#' @export showSignificance
#' @export showVerticalSignificance
#' @export showHorizontalSignificance
#'
######################################################################################

showSignificance <- function(
    x, 
    y,      
    width,
    text		  = NULL, 
    panel         = list(), #
    segmentParams = list(), # optional: sent to geom_segment
    textParams    = list()  # optional: sent to geom_text
) {
	if( is.null(text) || text == "") text = " "
    if (length(x) == 2) 
        showHorizontalSignificance(x, y, width, text, panel, segmentParams, textParams)
    else if (length(y) == 2)
        showVerticalSignificance(x, y, width, text, panel, segmentParams, textParams)
    else
        stop("superb::ERROR: impossible to determine if the annotation is horizontal or vertical...")
}

showHorizontalSignificance <- function(
    x, 
    y,      
    width,
    text, 
    panel         = list(), #
    segmentParams = list(), # optional: sent to geom_segment
    textParams    = list()  # optional: sent to geom_text
) {
    if (length(x) != 2) 
        stop ("superb::ShowSignificance: x must be a vector of 2 (left and right boundaries).")
    mysym <- function(x) { if(is.character(x)) sym(x) else x }

    # build data frames for the line segments and the text
    l1 <- data.frame(x = x[1], xend = x[2], y = y, yend = y)
    l2 <- data.frame(x = x,    xend = x,    y = y, yend = y)
	l2$yend <- l2$yend + width # to handle multiple length
    tx <- data.frame("label" = text, "x" = sum(x)/2, y = y)

    # if there are panels, add panel information to data frames.
    if ( !identical(panel, list() )) {
        l1 = data.frame(l1, data.frame(panel) )
        l2 = data.frame(l2, data.frame(panel) )
        tx = data.frame(tx, data.frame(panel) )
    }

    list(
        do.call( geom_segment, modifyList(
            list(data = l1, inherit.aes = FALSE, 
                #mapping = aes_string(x = "x", y = "y", yend = "yend", xend = "xend") 
                mapping = aes(x = x, y = y, yend = yend, xend = xend) 
            ),
            segmentParams[names(segmentParams) != "arrow"]
        ) ),
        do.call( geom_segment, modifyList(
            list(data = l2, inherit.aes = FALSE, 
                #mapping = aes_string(x = "x", y = "y", yend = "yend", xend = "xend") 
                mapping = aes(x = x, y = y, yend = yend, xend = xend) 
            ),
            segmentParams
        ) ),
        do.call( geom_text, modifyList(
            list(data = tx, inherit.aes = FALSE, 
                #mapping = aes_string(x = "x", y = "y", label = "label"), 
                mapping = aes(x = x, y = y, label = label), 
                hjust = 0.5, vjust = ifelse(sign(width[1])==1, 3 * sign(width[1])/2, sign(width[1])/2)
            ),
            textParams,
        ) )
    )

}



showVerticalSignificance <- function(
    x, 
    y,      
    width,
    text, 
    panel         = list(), #
    segmentParams = list(), # optional: sent to geom_segment
    textParams    = list()  # optional: sent to geom_text
) {
    if (length(y) != 2) 
        stop ("superb::ShowVerticalSignificance: y must be a vector of 2 (up and down boundaries).")

    # build data frames for the line segments and the text
    l1 <- data.frame(x = x, xend = x, y = y[1], yend = y[2])
    l2 <- data.frame(x = x, xend = x, y = y, yend = y) 
	l2$xend <- l2$xend + width # to handle multiple length
    tx <- data.frame("label" = text, "y" = sum(y)/2, x = x)

    # if there are panels, add panel information to data frames.
    if ( !identical(panel, list() )) {
        l1 = data.frame(l1, data.frame(panel) )
        l2 = data.frame(l2, data.frame(panel) )
        tx = data.frame(tx, data.frame(panel) )
    }

    list(
        do.call( geom_segment, modifyList(
            list(data = l1, inherit.aes = FALSE, 
                #mapping = aes_string(x = "x", y = "y", yend = "yend", xend = "xend") 
                mapping = aes(x = x, y = y, yend = yend, xend = xend) 
            ),
            segmentParams[names(segmentParams) != "arrow"]
        ) ),
        do.call( geom_segment, modifyList(
            list(data = l2, inherit.aes = FALSE, 
                #mapping = aes_string(x = "x", y = "y", yend = "yend", xend = "xend") 
                mapping = aes(x = x, y = y, yend = yend, xend = xend) 
            ),
            segmentParams
        ) ),
        do.call( geom_text, modifyList(
            list(data = tx, inherit.aes = FALSE, 
                #mapping = aes_string(x = "x", y = "y", label = "label"), 
                mapping = aes(x = x, y = y, label = label), 
                hjust = 0.5, vjust = ifelse(sign(width)==1,3 * sign(width)/2,sign(width)/2), angle = 270
            ),
            textParams,
        ) )
    )

}