R/save-plot.R

In poissonconsulting/poiscon: Poisson Consulting Utility Functions

#' @title Save plot
#'
#' @description
#' Saves current plot as a png file in current plots folder. The dpi is
#' given by option poiscon.dpi which by default is 320.
#'
#' @param name a character scalar of the name of the object.
#' @param type a character scalar of the type of folder to save in.
#' @param save_rows an integer scalar indicating the maximum of rows to save
#' from the plot data as a csv file.
#' @param report logical scalar indicating whether the plot should be displayed
#' to an analysis report.
#' @param caption character scalar of caption.
#' @param width a numeric scalar indicating the percent of the page width (or
#' if 10 or less the width of the page in inches). By default the width is
#' taken from the width of the previous gwindow.
#' @param height a numeric scalar indicating the percent of the page height (or
#' if 10 or less the width of the page in inches). By default the height is
#' taken from the height of the previous gwindow.
#' @param plot Plot to save, defaults to last plot displayed.
#' @return Saves current plot as png file in current plots folder.
#' @seealso \code{\link{gwindow}}
#' @importFrom ggplot2 ggsave last_plot
#' @export
save_plot <- function(name = "plot", type = "figures", save_rows = 100, report = TRUE,
  caption = NULL, width = NULL, height = NULL, plot = ggplot2::last_plot()) {

  if (is.null(plot)) {
    warning("plot '", name, "' is NULL")
    return(invisible(NULL))
  }
  if (is.null(caption))
    caption <- ""
  if (is.null(width))
    width <- 0
  if (is.null(height))
    height <- 0

  assert_that(is.string(name))
  assert_that(is.string(type))
  assert_that(is.flag(report) && noNA(report))
  assert_that(is.string(caption))
  assert_that(is.count(save_rows))
  assert_that(is.number(width))
  assert_that(is.number(height))

  if (type != "figures")
    report <- FALSE

  page_width <- getOption("poiscon.page_width", 6)
  dpi <- getOption("poiscon.dpi", 320)

  if (width == 0)
    width <- getOption("poiscon.gwindow.width", 100)
  if (height == 0)
    height <- getOption("poiscon.gwindow.height", width)

  if (width <= 10)
    width <- round(width/page_width * 100)

  if (height <= 10)
    height <- round(height/page_width * 100)

  file <- file.path(get_plots_folder(type = type), name)

  obj <- list(plot = plot, width = width, height = height, report = report,
    caption = caption)

  saveRDS(obj, file = replace_ext(file, "rds"))

  data <- obj$plot$data

  if (save_rows > nrow(data)) {
    row.names <- row.names(data)
    row.names <- !(is.null(row.names) || identical(row.names, as.character(1:nrow(data))))

    utils::write.csv(data, file = replace_ext(file, "csv"), row.names = row.names)
  }

  width <- width/100 * page_width
  height <- height/100 * page_width

  ggsave(replace_ext(file, "png"), plot = plot, width = width, height = height, dpi = dpi)
#  ggsave(replace_ext(file, "pdf"), plot = plot, width = width, height = height, dpi = dpi)
  invisible(NULL)
}