xmile: Create a new stock-and-flow model

In sdbuildR: Easily Build, Simulate, and Visualise Stock-and-Flow Models

Create a new stock-and-flow model

Description

Initialize a stock-and-flow model of class sdbuildR_xmile. You can either create an empty stock-and-flow model or load a template from the model library.

Usage

xmile(name = NULL)

Arguments

name

Name of the template to load. If NULL, an empty stock-and-flow model will be created with default simulation parameters and a default header. If specified, name should be one of the available templates: logistic_model: Population growth with carrying capacity SIR: Epidemic model (Susceptible-Infected-Recovered) predator_prey: Lotka-Volterra dynamics cusp: Cusp catastrophe model Crielaard2022: Eating behavior (doi: 10.1037/met0000484) coffee_cup: Temperature equilibration (Meadows) bank_account: Compound interest (Meadows) Lorenz: Lorenz attractor (chaotic) Rossler: Rossler attractor (chaotic) vanderPol: Van der Pol oscillator Duffing: Forced Duffing oscillator Chua: Chua's circuit (chaotic) JDR: Job Demands-Resources Theory as formalized in Evers et al. (submitted)

Details

Do not edit the object manually; this will likely lead to errors downstream. Rather, use header(), sim_specs(), build(), macro(), and model_units() for safe manipulation.

Value

A stock-and-flow model object of class sdbuildR_xmile. Its structure is based on XML Interchange Language for System Dynamics (XMILE). It is a nested list, containing:

header

Meta-information about model. A list containing arguments listed in header().

sim_specs

Simulation specifications. A list containing arguments listed in sim_specs().

model

Model variables, grouped under the variable types stock, flow, aux (auxiliaries), constant, and gf (graphical functions). Each variable contains arguments as listed in build().

macro

Global variable or functions. A list containing arguments listed in macro().

model_units

Custom model units. A list containing arguments listed in model_units().

Use summary() to summarize, as.data.frame() to convert to a data.frame, plot() to visualize.

See Also

build(), header(), macro(), model_units(), sim_specs()

Examples

sfm <- xmile()
summary(sfm)



# Load a template
sfm <- xmile("Lorenz")
sim <- simulate(sfm)
plot(sim)

sdbuildR documentation built on Nov. 19, 2025, 5:07 p.m.