Variance Plot

Shows the greatcircle of the shortest distance between a set of vectors to a specified vector in a stereoplot. The greatcircles are color-coded by the angular distance.

Usage

variance_plot(
  x,
  y = NULL,
  .mean = c("geodesic", "arithmetic", "projected"),
  show.center = TRUE,
  segments = TRUE,
  upper.hem = NULL,
  earea = NULL,
  ...
)

Arguments

x

object of class "Vec3", "Line", "Ray", "Plane", "Pair", or "Fault", where the rows are the observations and the columns are the coordinates.

y

The vector from which the variance should be visualized (only one vector allowed). When NULL, then the mean vector of x is used (the default).

.mean

character. The type of mean to be used if y is NULL. One of "geodesic" (the default), "arithmetic" or "projected".

show.center

logical. Whether the center point y of the mean should be highlighted in the plot.

segments

logical. Whether the segments should be shown or only the points?

upper.hem

logical. Whether the projection is shown for upper hemisphere (TRUE) or lower hemisphere (FALSE). Defaults to getOption("structr.upper.hem").

earea

logical. Projection, either TRUE for Lambert equal-area projection, or FALSE for meridional stereographic projection. Defaults to getOption("structr.earea").

...

optional arguments passed to assign_col()

Value

list. angles is a vector of the geodesic angles (in degrees) between all vectors in x and y (or the mean), and var is a scalar giving the Fréchet variance.

See also

stereo_segment(), sph_mean(), geodesic_mean(), projected_mean(), geodesic_var()

Examples

variance_plot(example_lines)

variance_plot(example_planes, example_planes[1, ], segments = FALSE)