simTs2D {smfsb}

Simulate a model on a regular grid of times, using a function (closure) for advancing the state of the model

Description

This function simulates single realisation of a model on a 2D regular spatial grid and regular grid of times using a function (closure) for advancing the state of the model, such as created by StepGillespie2D.

Usage

simTs2D(x0,t0=0,tt=100,dt=0.1,stepFun,verb=FALSE,...)

Arguments

x0

The initial state of the process at time t0, a 3d array with dimensions corresponding to reacting species and two spatial dimensions.

t0

The initial time to be associated with the initial state x0. Defaults to 0.

tt

The terminal time of the simulation.

dt

The time step of the output. Note that this time step relates only to the recorded output, and has no bearing on the accuracy of the simulation process.

stepFun

A function (closure) for advancing the state of the process, such as produced by StepGillespie2D.

verb

Output progress to the console and graphics window (this function can be very slow).

...

Additional arguments will be passed to stepFun.

Value

An R 4d array representing the simulated process. The dimensions are species, 2 space, and time.

See Also

StepGillespie2D, simTs1D

Examples

data(spnModels)
m=20; n=30; T=15
x0=array(0,c(2,m,n))
dimnames(x0)[[1]]=c("x1","x2")
x0[,round(m/2),round(n/2)]=LV$M
stepLV2D = StepGillespie2D(LV,c(0.6,0.6))
xx = simTs2D(x0,0,T,0.2,stepLV2D,verb=TRUE)
N = dim(xx)[4]
op=par(mfrow=c(1,2))
image(xx[1,,,N],main="Prey",xlab="Space",ylab="Time")
image(xx[2,,,N],main="Predator",xlab="Space",ylab="Time")
par(op)