rk4 {simecol}R Documentation

Runge-Kutta 4th order integration

Description

Solving initial value problems for systems of first-order ordinary differential equations (ODEs) using the classical Runge-Kutta 4th order integration. This is a special version designed to work with odeModel objects.

Usage

  rk4(y, times, func, parms) 
  # rk4(y) 

Arguments

y the odeModel object to be solved.
times placeholder for compatibility with the odesolve package
func placeholder for compatibility with the odesolve package
parms placeholder for compatibility with the odesolve package

Details

The solver method rk4 is used to simulate ODE models. It creates a local environment in a way that parameters, inputs and equations are visible within the main function of the odeModel. Normally, this function is called indirectly from sim.

Value

A list of the model outputs (states ...) for all timesteps.

See Also

sim, parms lsoda, iteration, original rk4 from the odesolve package.

Examples

  # ordinary usage
  data(lv)
  solver(lv) <- "rk4"
  plot(sim(lv))

  # alternative usage
  rk4(lv)

[Package simecol version 0.3-11 Index]