R/groupedBar.formula.R

In CarletonStats: Functions for Statistics Classes at Carleton College

#' @describeIn groupedBar Grouped bar chart
#' @export

groupedBar.formula <-
function(formula, data=parent.frame() , subset,  ...)
{

    if (length(formula) > 3L) stop("'formula' incorrect")

    m <- match.call(expand.dots = FALSE)
    if (is.matrix(eval(m$data, parent.frame())))
        m$data <- as.data.frame(data)
    m[[1L]] <- as.name("model.frame")
    m$... <- NULL
    mf <- eval(m, parent.frame())
    varnames <- names(mf)

    nmiss <- length(attr(mf, "na.action"))
    if (nmiss > 0)
     cat("\n ", nmiss, "observation(s) removed due to missing values.\n")

     if (length(formula) == 2L) {
        do.call("groupedBar", c(list(resp = unlist(mf), resp.name=varnames[1]), list(...)))

      } else {

     response <- attr(attr(mf, "terms"), "response")
     y <- mf[[response]]
     g <- mf[[-response]]
     names(g) <- varnames[2]

     y <- do.call("groupedBar", c(list(y, g, cond.name=varnames[2], resp.name=varnames[1]), list(...)))
    }#end else
}