Plot a list of indicatrixes

Draws all indicatrixes in an indicatrix_list, optionally creating a new plot or adding to an existing one. Can colour-code the fill by a distortion metric.

# S3 method for class 'indicatrix_list'
plot(
  x,
  scale = 1e+05,
  n = 72,
  col = "#FF990055",
  border = "black",
  add = FALSE,
  show.axes = TRUE,
  show.circle = TRUE,
  fill.by = NULL,
  palette = NULL,
  ncolors = 64L,
  ...
)

Arguments

x

an indicatrix_list (from indicatrix())

scale

scaling factor for ellipse size in projected units

n

number of points per ellipse

col

fill colour. If a single colour, used for all ellipses. If NULL and fill.by is set, colours are generated automatically.

border

border colour

add

logical; add to existing plot? If FALSE, creates a new plot sized to contain all ellipses.

show.axes

TRUE, FALSE, or a named list of graphical parameters. See plot.indicatrix() for defaults.

show.circle

TRUE, FALSE, or a named list of graphical parameters. Default TRUE for the list method (the circle-vs-ellipse comparison makes distortion visible at map scale). See plot.indicatrix() for defaults.

fill.by

character; name of a distortion metric to colour-code the fill. One of "scale_area", "angle_deformation", "scale_h", "scale_k", "scale_a", "scale_b". Default NULL (uniform fill).

palette

colour palette function (default grDevices::hcl.colors())

ncolors

number of colours in the palette (default 64)

...

passed to plot.indicatrix()

Value

The input x, invisibly.

See also

indicatrix(), plot.indicatrix(), tissot_map()

Examples

xy <- expand.grid(seq(-150, 150, by = 30), seq(-60, 60, by = 30))
r <- tissot(xy, "+proj=robin")
ii <- indicatrix(r)

## Uniform fill
plot(ii, scale = 6e5, add = FALSE)
tissot_map()


## Colour by areal distortion
plot(ii, scale = 6e5, add = FALSE, fill.by = "scale_area")
tissot_map()