initialize-methods | R Documentation |
This function is used to initialize objects derived from the
simObj
superclass, it is by default automatically called during
object creation and by sim
.
## S4 method for signature 'simObj'
initialize(.Object, ...)
.Object |
|
... |
provided for compatibility with the default method of
|
Generic function: see new
.
The initialize
function is normally called implicitly by
new
to create new objects. It may also be called explicitly
to return a cloned and re-initialized object.
The simecol version of initialize
provides an
additonal mechanism to call a user specified function provided in
the initfun
slot of a simObj
instance that can
perform computations during the object creation process. The
initfunc
must have obj
as its only argument and must
return the modified version of this obj
, see examples
below. As a side effect end to ensure consistency,
initialize
clears outputs stored in slot out
from
former simulations.
simObj
, new
## Note: new calls initialize and initialize calls initfunc(obj)
lv_efr <- new("odeModel",
main = function (time, init, parms, ...) {
x <- init
p <- parms
S <- approxTime1(inputs, time, rule=2)["s.in"]
dx1 <- S * p["k1"] * x[1] - p["k2"] * x[1] * x[2]
dx2 <- - p["k3"] * x[2] + p["k2"] * x[1] * x[2]
list(c(dx1, dx2))
},
parms = c(k1=0.2, k2=0.2, k3=0.2),
times = c(from=0, to=100, by=0.5),
init = c(prey=0.5, predator=1),
solver = "lsoda",
initfunc = function(obj) {
tt <- fromtoby(times(obj))
inputs(obj) <- as.matrix(data.frame(
time = tt,
s.in = pmax(rnorm(tt, mean=1, sd=0.5), 0)
))
obj
}
)
plot(sim(lv_efr)) # initialize called automatically
plot(sim(lv_efr)) # automatic initialization, different figure
lv_efr<- initialize(lv_efr) # re-initialize manually
plot(sim(lv_efr, initialize = FALSE)) # simulation with that configuration
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.