parms: Accessor Functions for `simObj' Objects

Description

Get or set simulation model parameters, main or sub-equations, initial values, time steps or solvers and extract simulation results.

Usage

parms(obj, ...)
parms(obj) <- value
main(obj, ...)
main(obj) <- value
equations(obj, ...)
equations(obj) <- value
init(obj, ...)
init(obj) <- value
inputs(obj, ...)
inputs(obj) <- value
times(obj, ...)
times(obj) <- value
solver(obj, ...)
solver(obj) <- value
observer(obj, ...)
observer(obj) <- value
initfunc(obj, ...)
initfunc(obj) <- value
out(obj, ...)
out(obj) <- NULL

Arguments

obj

A valid simObj instance.

value

Named list, vector, function or other data structure (depending on the slot and model class) with the same structure as the value returned by parms. Either all or a subset of values (e.g. single elements of vectors or lists) can b

...

Reserved for method consistency.

Value

A list, named vector, matrix or function (for main slot) or list of functions (equation slot) or other appropriate data structure depending on the class of the model object.

Details

These are the accessing functions for parms, times etc.

Please take care of the semantics of your model when changing slots. All, element names, data structure and values have to correspond to you model object definition. For example in init the applied names must exactly correspond to the names and number (!) of state variables. The restrictions of parms or equations are less strict (additional values for ``future use'' are allowed). The function times allows either to assign or to modify a special vector with three elements named from, to and by or to overwrite times with an un-named sequence (e.g. seq(1, 100, 0.1). To ensure object consistency function out cannot assign arbitrary values. It can only extract or delete the contents (by assigning NULL) of the out-slot.

Examples

Run this code

data(lv)
parms(lv)
parms(lv)       <- c(k1 = 0.2, k2 = 0.5, k3 = 0.3)
parms(lv)["k2"] <- 0.5

data(conway)
parms(conway)
parms(conway)$srv <- c(2, 2)
parms(conway)

## add a new named parameter value
parms(lv)["dummy"] <- 1
## remove dummy parameter
parms(lv) <- parms(lv)[names(parms(lv)) != "dummy"]

## simulation and extraction of outputs
lv <- sim(lv)
o <- out(lv)

## remove outputs from object
out(lv) <- NULL
## store object persistently to the disk
save(lv, file = "lv.Rdata")           # in binary form
dput(as.list(lv), file = "lv-list.R") # in text form