R/boxplot.R

In dnzmarcio/ntimes: ntimes

#'Boxplot
#'
#'@description Plot boxplot for several variables.
#'
#'@param data a data frame with the variables.
#'@param group a character value indicating the group variable.
#'@param labels a list of labels with components given by their variable names.
#'@param save a logical value indicating whether the output
#'should be saved as a jpeg file.
#'@param fig.height a numeric value indicating the height (in) of the file.
#'@param fig.width a numeric value indicating the width (in) of the file.
#'@param std_fun a function to plot a boxplot when \code{group = NULL}.
#'It must follow the same structure of \code{\link{std_boxplot}}.
#'@param std_fun_group a function to plot a boxplot when \code{group}
#'is provided. It must follow the same structure of
#'\code{\link{std_boxplot_group}}.
#'@param ... additional input arguments that may be used when creating your own function.
#'
#'@details The functions \code{\link{std_boxplot}} and
#'\code{\link{std_boxplot_group}} can be modified by the user in order to
#'customize the boxplots a prior.
#'The plots also can be modified a posterior as a regular ggplot object.
#'See \code{\link[ggplot2]{geom_boxplot}}, \code{\link{std_boxplot}} and
#'\code{\link{std_boxplot_group}}.
#'
#'@return a list of ggplot objects with each item named by the column names from
#'\code{var}.
#'
#'@examples
#'data(iris)
#'
#'iris |> nt_boxplot(group = Species)
#'
#'@import ggplot2 dplyr
#'@importFrom rlang enquo quo_is_null
#'@importFrom dplyr select
#'@importFrom purrr map2
#'
#'@export
nt_boxplot <-  function(data, group = NULL, labels = NULL,
                        save = FALSE, fig.height = 5, fig.width = 5,
                        std_fun = std_boxplot,
                        std_fun_group = std_boxplot_group,
                        ...){

  group <- enquo(group)

  if (!quo_is_null(group)){
    vars <- select(.data = data, -!!group)
    group <- select(.data = data, !!group)
    group.name <- names(group)
  } else {
    vars <- data
    group <- NULL
    group.name <- NULL
  }

  vars.name <- names(vars)

  if (!is.null(labels)){
    vars <- data_labeller(vars, labels)
    vars.label <- map2(.x = vars, .y = as.list(vars.name),
                       .f = extract_label)

    if (!is.null(group)){
      group <- data_labeller(group, labels)
      group.label <- extract_label(group[[1]], group.name)
    }

  } else {
    vars.label <- map2(.x = vars, .y = as.list(vars.name),
                       .f = extract_label)

    if (!is.null(group)){
      group.label <- extract_label(group, group.name)
    }
  }

  out <- pmap(.l = list(vars, vars.name, vars.label),
              .f = aux_boxplot,
              group = group, group.name = group.name, group.label = group.label,
              fig.height = fig.height, fig.width = fig.width, save = save,
              std_fun = std_fun, std_fun_group = std_fun_group,
              ... = ...)

  return(out)
}

aux_boxplot <- function(var, var.name, var.label, group, group.name, group.label,
                        fig.height, fig.width, save,
                        std_fun, std_fun_group, ...){

  out <- list()

  if (is.null(group)) {
    gp <- std_fun(var = var,
                  var.label = var.label,
                  ... = ...)

    if(save)
      gp <- gp + ggsave(filename = paste0("box_", var.name, ".jpeg"),
                        height = fig.height, width = fig.width)

    out <- gp

  } else {
    gp <- std_fun_group(var = var,
                        group = group[[1]],
                        group.label = group.label,
                        var.label = var.label,
                        ... = ...)

    if (save)
      gp <- gp + ggsave(filename = paste0("box_", group.name, "_",
                                 var.name, ".jpeg"),
                        height = fig.height,
                        width = fig.width)

    out <- gp
  }

  return(out)
}

#'Standard boxplot
#'
#'@import ggplot2
#'@description A function to plot a boxplot without groups.
#'
#'@param var a numeric vector.
#'@param var.label a character value specifying the variable label.
#'@param ... additional input arguments that may be used when creating your own function.
#'
#'@details This function defines the standard boxplot without groups to be
#'plotted by the function \code{\link{nt_boxplot}}. It can be modified by the
#'user. See more details in \code{\link[ggplot2]{geom_boxplot}}.
#'
#'@return a ggplot object.
#'
#'@export
std_boxplot <- function(var, var.label, ...){

  ### Data
  data_plot <- data.frame(var = var)

  ### Basic Plot
  out <- ggplot(data_plot, aes_string(x = NA, y = "var")) +
    stat_boxplot(geom = "errorbar", width = 0.5) +
    geom_boxplot(fill = "grey80", outlier.shape = NA)  +
    geom_jitter(shape = 16, size = 1.5,
                position = position_jitter(width = 0.2))

  ### Formatting
  out <- out + labs(y = var.label) +
    theme(axis.ticks.x = element_blank(),
          axis.text.x = element_blank(),
          axis.title.x = element_blank()) +
    theme_classic()

  return(out)
}

#'Standard boxplot by group
#'
#'@description A function to plot a boxplot with groups.
#'
#'@param var a numeric vector.
#'@param group a character vector.
#'@param var.label a character value specifying the variable label.
#'@param group.label a character value specifying the group label.
#'@param ... additional input arguments that may be used when creating your own function.
#'
#'@details This function defines the standard boxplot with groups to be plotted
#'by the function \code{\link{nt_boxplot}}. It can be modified by the user.
#'See more details in \code{\link[ggplot2]{geom_boxplot}}.
#'
#'@return a ggplot object.
#'
#'@export
std_boxplot_group <- function(var, group, var.label, group.label, ...){

  ### Data
  data_plot <- data.frame(var = var, group = group)

  ### Basic plot
  out <- ggplot(data_plot, aes_string(y = "var", x = "group")) +
    stat_boxplot(geom = "errorbar", width = 0.5) +
    geom_boxplot(outlier.shape = NA, fill = "grey80")  +
    geom_jitter(shape = 16, size = 1.5,
                position = position_jitter(width = 0.2))

  ### Formatting
  out <- out + labs(y = var.label, x = group.label) +
    theme_classic() +
    theme(legend.position = "none")

  return(out)
}