wavefront: Wavefront Expansion Accumulation

In spacc: Fast Spatial Species Accumulation Curves

Wavefront Expansion Accumulation

Description

Accumulate species within an expanding radius from seed points. Models invasion spread from introduction points.

Usage

wavefront(
  x,
  coords,
  n_seeds = 50L,
  r0 = 0,
  dr = NULL,
  n_steps = 50L,
  distance = c("euclidean", "haversine"),
  progress = TRUE,
  seed = NULL
)

Arguments

x	A site-by-species matrix.
coords	A data.frame with x and y columns, or a spacc_dist object.
n_seeds	Integer. Number of random starting points.
r0	Numeric. Initial radius. Default 0.
dr	Numeric. Radius increment per step. Default auto-calculated.
n_steps	Integer. Number of expansion steps. Default 50.
distance	Character. Distance method.
progress	Logical. Show progress?
seed	Integer. Random seed.

Value

An object of class spacc_wavefront containing:

curves	Matrix of species counts (n_seeds x n_steps)
radius	Vector of radius values
sites_included	Matrix of sites included at each step

References

Shigesada, N. & Kawasaki, K. (1997). Biological Invasions: Theory and Practice. Oxford University Press.

Examples

coords <- data.frame(x = runif(50), y = runif(50))
species <- matrix(rbinom(50 * 30, 1, 0.3), nrow = 50)
wf <- wavefront(species, coords, n_seeds = 20, n_steps = 50)
plot(wf)

spacc documentation built on June 20, 2026, 5:07 p.m.