Render pre-computed circular mean arrows on a radial plot

Takes a data frame produced by [compute_circ_mean()] and renders each row as a `geom_segment()` arrow. `mean_dir` must be in unit-circle convention (0 = East, CCW), as returned by [compute_circ_mean()]. Rows where `mean_dir` or `resultant_R` is `NA` are silently skipped.

Usage

add_circ_mean(
  summary_df,
  colour_col = NULL,
  linewidth = 1,
  colour = NULL,
  arrow_length_cm = 0.2,
  axial = FALSE,
  ...,
  color_col = NULL,
  color = NULL
)

Arguments

summary_df

Data frame with columns `mean_dir` (UC radians, 0 to 2pi) and `resultant_R` (0–1). Typically the output of [compute_circ_mean()].

colour_col, color_col

Optional. Name of a column in `summary_df` to map to the colour aesthetic. Ignored when `colour` is also supplied. `color_col` is the American-spelling alias.

linewidth

Line width of the arrow segment. Default `1`.

colour, color

Fixed colour. When `NULL` (default) and `colour_col` is set, colour is mapped from that column; when `NULL` and no `colour_col`, draws in `"black"`. Supplying any colour string always overrides `colour_col`. `color` is the American-spelling alias.

arrow_length_cm

Arrowhead length in cm. Default `0.2`.

axial

Logical. Render the overlay for axial (bidirectional, mod-pi) data: the mean is drawn as a double-headed axis through the centre. Default `FALSE`.

...

Additional arguments forwarded to `geom_segment` (e.g. `linetype`, `alpha`, or a custom `arrow` spec that overrides the default).

Value

A `geom_segment()` layer.

See also

[compute_circ_mean()], [add_heading_arrow()]