upca {simecol}R Documentation

The Uniform Period Chaotic Amplitude Model

Description

simecol example: resource-predator-prey model, which is able to exhibit chaotic behaviour.

Usage

  data(upca)

Format

S4 object according to the odeModel specification. The object contains the following slots:

main
The differential equations for predator prey and resource with:
u
resource (e.g. grassland or phosphorus),
v
producer (prey),
w
consumer (predator).
equations
Two alternative (and switchable) equations for the functional response.
parms
Vector with the named parameters of the model, see references for details.
times
Simulation time and integration interval.
init
Vector with start values for u, v and w.
solver
Character string with the integration method.

Details

To see all details, please have a look into the implementation and the original publications.

References

Blasius, B., Huppert, A., and Stone, L. (1999) Complex dynamics and phase synchronization in spatially extended ecological systems. Nature, 399 354–359.

Blasius, B. and Stone, L. (2000) Chaos and phase synchronization in ecological systems. International Journal of Bifurcation and Chaos, 10 2361–2380.

See Also

sim, parms, init, times.

Examples

    data(upca)
    plot(sim(upca))

    # omit stabilizing parameter wstar
    parms(upca) <- list(wstar=0)
    plot(sim(upca))

    # change functional response from
    # Holling II (default) to Lotka-Volterra
    equations(upca)$f <- function(x, y, k) x * y
    plot(sim(upca))

[Package simecol version 0.4-2 Index]