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Spoke layer

Source: R/mark.R
mark_spoke.Rd

Draws a radial segment ("spoke") from each point (x, y) at angle (radians) for radius length. A first-class primitive for direction/velocity fields and for radial network edges whose endpoints are naturally expressed in polar terms.

Usage

mark_spoke(
  plot,
  mapping = NULL,
  data = NULL,
  position = NULL,
  ...,
  rasterize = FALSE,
  rasterize_dpi = 300,
  rasterize_dev = "cairo"
)

Arguments

plot

A plotit object

mapping

Optional new aesthetics (must include x, y, angle in radians, and radius)

data

Optional data for this layer

position

Position adjustment.

...

Other arguments passed to geom_spoke

rasterize

If TRUE, rasterize via ggrastr::rasterise().

rasterize_dpi

DPI for rasterization (default 300).

rasterize_dev

Graphics device for rasterization (default "cairo").

Value

Modified plotit object

References

Vega-Lite: Spoke

Examples

df <- data.frame(
  x = c(0, 1, 2), y = c(0, 1, 0),
  angle = c(0, pi / 2, pi), radius = c(0.5, 0.8, 0.3)
)
plotit(df, encode(x = x, y = y, angle = angle, radius = radius)) |>
  mark_spoke()