These functions allow you to get or set the resource parameters stored in a
MizerParams object. The resource parameters are stored as a named list with
the slot names r_pp, kappa, lambda, n, w_pp_cutoff. For their
meaning see Details below. If you change these parameters then this will
recalculate the resource rate and the resource capacity, unless you have set
custom values for these. If you have specified a different resource dynamics
function that requires additional parameters, then these should also be added
to the resource_params list.
resource_params(params) resource_params(params) <- value
| params | A MizerParams object |
|---|---|
| value | A named list of resource parameters. |
The resource parameters r_pp and n are used to set the intrinsic
replenishment rate \(r_R(w)\) for the resource at size \(w\) to
$$r_R(w) = r_{pp}\, w^{n-1}.$$
The resource paramters kappa, lambda and w_pp_cutoff are used to set
the intrinsic resource carrying capacity capacity \(c_R(w)\) at size \(w\)
is set to
$$c_R(w) = \kappa\, w^{-\lambda}$$
for all \(w\) less than w_pp_cutoff and zero for larger sizes.
If you use the default semichemostat dynamics for the resource then these
rates enter the equation for the resource abundance density as
$$\frac{\partial N_R(w,t)}{\partial t} = r_R(w) \Big[ c_R (w) - N_R(w,t) \Big] - \mu_R(w, t) N_R(w,t)$$
where the mortality \(\mu_R(w, t)\) is
due to predation by consumers and is calculate with getResourceMort().
You can however set up different resource dynamics with
resource_dynamics<-().
Other functions for setting parameters:
gear_params(),
setExtMort(),
setFishing(),
setInitialValues(),
setInteraction(),
setMaxIntakeRate(),
setMetabolicRate(),
setParams(),
setPredKernel(),
setReproduction(),
setResource(),
setSearchVolume(),
species_params()
resource_params(NS_params) #> $kappa #> [1] 1e+11 #> #> $lambda #> [1] 2.133333 #> #> $r_pp #> [1] 10 #> #> $n #> [1] 0.6666667 #> #> $w_pp_cutoff #> [1] 9.820907 #> # Doubling the replenishment rate params <- NS_params resource_params(params)$r_pp <- 2 * resource_params(params)$r_pp