stabClass: Stability Classification

In cboettig/bs-tipping: Bifurcation or State Tipping in a Trophic Cascade Experiment

Description

Find equilibria for a model of a trophic cascade

Usage

stabClass(qE, pars, func = fs2D, Jvals = seq(0, 2000, length.out = 2),
  Fvals = seq(10, 20, length.out = 2))

Arguments

qE	numeric scalar representing harvest rate; reasonable values might be between 0 and 2
pars	a named numeric vector of optional additional parameter values to be passed to func
func	function whose stability is to be classified; nominally this is fs2D, a wrapper for fishStep2D; currently this function only works with the default b/c getRoot_df hasn't been set up to accept other functions as an argument
Jvals, Mvals	numeric vector of J0 (juvenile bass) or F0 (planktivorous fish) values over which to search for equilibria

Value

a data.frame with a row for each equilibrium point found, and columns for the J0,F0 coordinates of those points, a character describing its stability classification, the trace (tr) and determinant (Delta) of the Jacobian matrix at that point, the 'discriminant' value (tr^2 - 4*delta), and the parameter values supplied through qE and pars.

Examples

stabClass(qE=0.65)
qEvec <- seq(0.15, 1.5, length.out=10)
lout <- lapply(qEvec, stabClass)
do.call(rbind, lout)

cboettig/bs-tipping documentation built on May 5, 2019, 7:08 a.m.