dust_ode_control: Create a dust_ode_control object.

In mrc-ide/dust: Iterate Multiple Realisations of Stochastic Models

Create a dust_ode_control object.

Description

Create a control object for controlling the adaptive stepper for systems of ordinary differential equations (ODEs). The returned object can be passed into a continuous-time dust model on initialisation.

Usage

dust_ode_control(
  max_steps = NULL,
  atol = NULL,
  rtol = NULL,
  step_size_min = NULL,
  step_size_max = NULL,
  debug_record_step_times = NULL
)

Arguments

max_steps	Maxmimum number of steps to take. If the integration attempts to take more steps that this, it will throw an error, stopping the integration.
atol	The per-step absolute tolerance.
rtol	The per-step relative tolerance. The total accuracy will be less than this.
step_size_min	The minimum step size. The actual minimum used will be the largest of the absolute value of this step_size_min or .Machine$double.eps. If the integration attempts to make a step smaller than this, it will throw an error, stopping the integration.
step_size_max	The largest step size. By default there is no maximum step size (Inf) so the solver can take as large a step as it wants to. If you have short-lived fluctuations in your rhs that the solver may skip over by accident, then specify a smaller maximum step size here.
debug_record_step_times	Logical, indicating if we should record the steps taken. This information will be available as part of the statistics() output

Value

A named list of class "dust_ode_control"

Examples

# We include an example of logistic growth with the package
gen <- dust::dust_example("logistic")

# Create a control object, then pass it through as the ode_control
# parameter to the constructor:
ctrl <- dust::dust_ode_control(atol = 1e-3, rtol = 1e-3)
mod <- gen$new(list(r = 0.1, K = 100), 0, 1, ode_control = ctrl)

# When the model runs, the control parameters passed in to the
# constructor are used in the solution
mod$run(10)

# The full set of control parameters can be extracted:
mod$ode_control()

mrc-ide/dust documentation built on May 11, 2024, 1:08 p.m.