lv_interaction_log {gauseR}

Lotka-Volterra Interactions in Log Space

Description

Calculates dn/dt for n species in a Lokta-Volterra system, in log space, following the form: dlog(ni)/dt = (ri + aii * ni + sum_j(aij * nj)) This form can be helpful for optimization routines where species abundances are close to zero.

Usage

lv_interaction_log(time, n_log, parms)

Arguments

time

The time steps corresponding to each observation - exists to interface with ode function, but should be left blank.

n_log

A vector of species abundances, in log space

parms

A vector of parameters - the first n elements should be the growth rates r1, r2, ... rn for all n species. The remaining terms should be the elements of the interaction matrix A, listed in the order a11, a12, ... a1n, a21, a22, ... a2n, ... an1, an2, ... ann.

Value

vector of growth rates for each species in log space