RplotterPkg (version 0.1.3)

multi_panel_grid: multi_panel_grid

Description

Arranges a group of ggplot2 plots or grid::grob's into multiple panels.

Function creates a figure with title and arranges multiple plots/grobs across a given number of rows and columns. The function depends on the grid, gtable, and ggplotify packages.

Usage

multi_panel_grid(
  layout = NULL,
  title = NULL,
  title_fontsz = 20,
  plot_titles = NULL,
  y_tick_width = 0.5,
  cell_width = 8,
  cell_height = 8,
  do_grid = FALSE
)

Value

A ggplot2 class object

Arguments

layout

A list containing a list for plot objects or grob "plots", row locations "rows" vector, column locations "cols" vector. This argument is required.

title

A string that sets the title of the figure.

title_fontsz

A numeric that sets the title's font size. The default is 20.

plot_titles

A character vector with the same length as the number of plot objects that defines each of their titles. The parameter is used only if 'do_grid' is FALSE.

y_tick_width

A numeric that sets the width of the vertical column containing the y axis tick labeling. The default is 0.5 cm and may be increased when a wider labeling is needed.

cell_width

A numeric that sets the cell widths in the gtable in cm

cell_height

A numeric that sets the cell widths in the gtable in cm

do_grid

A logical which if TRUE will arrange the plot objects according to 'layout' without considering their scale and label components. You define the axis scaling, titling, etc for each individual plot object.

Details

The function has two modes of layout: a grid and a non-grid. In the grid layout, each plot submitted will be laid out "as-is" with no manipulation of labels, legends, or axis'.

For the non-grid layout, the function goes beyond just placing a group of plots across a grid of rows and columns. It is somewhat opinionated in favor of common titling/labeling and scaling that make sense for all the plots and provide the ability to compare. The function has a 'title' parameter that is assumed appropriate for all the plots--any titles/subtitles among the plots themselves will be removed. The first left y-axis scaling the function comes across will be used for all the plots. Similarly the first bottom x-axis scaling the function comes across will be assumed appropriate for all the plots. The first legend that is found is assumed right for all the plots and will be placed at the top in a horizontal direction. Of course none of these sub-elements among the plots need to exist and you are back to simply a grid of plots.

As an example of defining the 'layout' list argument, 'layout' has three named elements: "plots", "rows", and "cols". "plots" is a list of ggplot2 plot objects; "rows" defines the row number for each plot and "cols" defines the column number for each plot. If we have two plots with both plots on a single row then "rows" = c(1,1) and "cols" = c(1,2).

Examples

library(ggplot2)
library(ggplotify)
library(rlang)
library(grid)
library(gtable)
library(ggplotify)
library(purrr)
library(RplotterPkg)

years <- levels(RplotterPkg::gapminder_data$year)
build_plot <- function(id, dt, years){
  plot_dt <- dt[year == years[[id]], ]
  aplot <- RplotterPkg::create_scatter_plot(
    df = plot_dt,
    aes_x = "lifeExp",
    aes_y = "pop",
    aes_fill = "continent",
    x_limits = c(20, 80),
    x_major_breaks = seq(from = 20, to = 80, by = 10),
    y_limits = c(0, 400),
    y_major_breaks = seq(from = 0, to = 400, by = 50),
    subtitle = years[[id]],
    title = "Life Expectancy Across Continents",
    x_title = "Life Expectancy",
    y_title = "Population(1e+6)",
    pts_size = 5,
    legend_key_width = 0.8,
    legend_key_height = 0.6,
    show_minor_grids = FALSE,
    silent_NA_warning = TRUE
  )
  return(aplot)
}
plot_lst <- purrr::map(1:4,
  build_plot,
  dt = RplotterPkg::gapminder_data,
  years = years
)
layout <- list(
  plots = plot_lst,
  rows = c(1, 1, 1, 1),
  cols = c(1, 2, 3, 4)
)
RplotterPkg::multi_panel_grid(
  layout = layout,
  title = "Life expectancy vs population(millions) across continents",
  plot_titles = c("1952","1972","1992","2002"),
  cell_height = 12
)