Dumbbell comparison chart layer

Creates a dumbbell chart with two connected points showing before/after or paired comparisons. This is a syntax-sugar composite mark combining two mark_point calls and a geom_segment.

Usage

mark_dumbbell(
  plot,
  mapping = NULL,
  data = NULL,
  colour_start = "#4E79A7",
  colour_end = "#E15759",
  line_colour = "grey50",
  point_size = 3,
  line_width = 1,
  ...
)

Arguments

plot

A plotit object

mapping

Optional new aesthetics

data

Optional data for this layer

colour_start

Colour for the start point (default "#4E79A7").

colour_end

Colour for the end point (default "#E15759").

line_colour

Colour for the connecting line (default "grey50").

point_size

Size for both dumbbell points (default 3).

line_width

Width for the connecting line (default 1).

...

Other arguments passed to mark_point() calls

Value

Modified plotit object

Details

Equivalent expansion:

  p |> mark_rule(x = x, xend = x, y = y_start, yend = y_end) |>
       mark_point(x = x, y = y_start, colour = colour_start) |>
       mark_point(x = x, y = y_end, colour = colour_end)

Examples

df <- data.frame(cat = LETTERS[1:5], before = c(3, 5, 2, 8, 4),
                 after = c(7, 6, 5, 10, 6))
plotit(df, encode(x = cat, y = before, yend = after)) |>
  mark_dumbbell()