R/findbeta_plot.R

In PriorGen: Generates Prior Distributions for Proportions

#' The findbeta plot function
#'
#'
#' A function that plots any object of the class findbeta.
#'
#' @rdname plot.PriorGen
#' @param x An object of type findbeta produces of one of 
#' the other PriorGen functions.
#' @param ... More basic plot arguments
#' @examples
#' ## Example 1
#' ## Based on the available literature the mean value for the 
#' ## sensitivity of a test is expected to be generally low and 
#' ## its variance not that low but not that much neither.
#'
#' res_abs_1 <- findbeta_abstract(
#'   themean.cat = "Low",
#'   thevariance.cat = "Average"
#' )
#' plot(res_abs_1,
#'   main = "Plot of the findbeta_abstract function",
#'   lwd = 3, ylim = c(0, 7)
#' )
#'
#' ## Example 2
#' ## Hierarchical prior
#'
#' res_mult_1 <- findbetamupsi(
#'   themean = 0.10, percentile = 0.79,
#'   lower.v = TRUE, percentile.value = 0.26, psi.percentile = 0.95,
#'   percentile.median = 0.28, percentile95value = 0.3
#' )
#'
#' plot(res_mult_1,
#'   main = "Plot of the findbetamupsi function",
#'   lwd = 3, ylim = c(0, 7)
#' )
#'
#' @export
#'
plot.PriorGen <- function(x, ...) {
  findbeta.object <- x
  classchk <- as.character(class(findbeta.object))
  if (classchk != "PriorGen" && classchk != "PriorGen2") {
    stop("Provide an object of class PriorGen or PriorGen2")
  }
  if (length(findbeta.object) == 3) {
    a_plot <- findbeta.object$parameters[1]
    b_plot <- findbeta.object$parameters[2]
    x <- seq(0, 1, 0.001)
    y <- dbeta(seq(0, 1, 0.001), a_plot, b_plot)
    plot(x, y, ...)
  } else {
    a_plot <- mean(findbeta.object$param_upper$at)
    b_plot <- mean(findbeta.object$param_upper$bt)
    x <- seq(0, 1, 0.001)
    y <- dbeta(seq(0, 1, 0.001), a_plot, b_plot)
    plot(x, y, ...)
  }
}