R/plot_barchart_euros.R

In eufmdis.adapt: Analyse 'EuFMDiS' Output Files via a Shiny App

#' Plot bar chart with error bars an Euro notation
#'
#' Creates a bar chart with error bars using \code{ggplot2::geom_col}.
#'
#' @param x Data frame with columns \code{par} or \code{parameter} containing
#' the name of the parameter, \code{q2.5} or \code{q2_5} for the 2.5 percentiles
#' (i.e. the lower values for the error bars), \code{median} for the median
#' values (i.e. the height of the bars) and \code{q97.5} or \code{q97_5} for
#' the 97.5 percentiles (i.e. the upper values for the error bars).
#' @param country Character to be displayed in the Plot title.
#'
#' @return Returns an object of class \code{ggplot} and prints it to the
#' graphics device.
#' @importFrom magrittr %>%
#' @importFrom rlang .data
#' @seealso \code{\link{plot_barchart}}

# Example:
# x <- data.frame(
#   parameter = c("A", "B", "C"),
#   q2.5 = c(1,2,3),
#   median = c(2,4,5),
#   q97.5 = c(3.5, 4.5, 7)
# )
# eufmdis.adapt:::plot_barchart_euros(x, "my country")
#
# Author: Ian Kopacka
# Encoding: UTF-8
# Version: 2023-03-16
# ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

plot_barchart_euros <- function(x, country){

  # Normalise column names:
  names(x) <- tolower(names(x))
  names(x) <- gsub("[._]", "_", names(x))
  names(x)[names(x) == "par"] <- "parameter"
  ylab <- "Euros"

  # Find right scale:
  if (max(x$median > 1e7)){
    x <-
      x %>%
      dplyr::mutate(
        median = .data$median/1e6,
        q2_5 = .data$q2_5/1e6,
        q97_5 = .data$q97_5/1e6
      )
    ylab <- "Euros (in millions)"
  } else if (max(x$median > 1e4)){
    x <-
      x %>%
      dplyr::mutate(
        median = .data$median/1e3,
        q2_5 = .data$q2_5/1e3,
        q97_5 = .data$q97_5/1e3
      )
    ylab <- "Euros (in thousands)"
  }

  # Create plot:
  p <- ggplot2::ggplot(x) +
    ggplot2::geom_col(
      ggplot2::aes(x = .data$parameter, y = .data$median),
      fill = "#3AA1A6",
      alpha = 0.5
    ) +
    ggplot2::geom_errorbar(
      ggplot2::aes(
        x = .data$parameter,
        y = .data$median,
        ymin = .data$q2_5,
        ymax = .data$q97_5
      ),
      width = 0.4,
      colour = "orange",
      alpha = 0.9,
      linewidth = 1.3
    ) +
    ggplot2::coord_flip() +
    ggplot2::xlab("") +
    ggplot2::ylab(ylab) +
    ggplot2::ggtitle(
      paste0(
        "Country: ",
        toupper(country),
        "; the bars represent the median values, the error bars ",
        "represent the 95% range of variation."
      )
    ) +
    ggplot2::theme_minimal() +
    ggplot2::theme(
      text = ggplot2::element_text(size = 16),
      plot.title = ggplot2::element_text(size = 12),
      axis.title = ggplot2::element_text(size = 12)
    )
  print(p)
}