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Class <ModelConfig>

Source: R/class-ModelConfig.R
ModelConfig-class.Rd

<ModelConfig> is an S4 class containing the user-defined configuration for the Individual-based Model (IBM). It specifies key parameters such as the number of agents, the spatio-temporal resolution of the model, the bounding box (extent) of the area of calculation (AOC), the simulation start and end date.

Slots

movement_model

Character string, specifying the movement model to simulate agent trajectories. Currently supported options:

  • "di": Density-informed movement, where agent destinations stochastically generated based on population-level density maps.

  • "crw": Correlated Random Walk model, where movement directions follow probability distributions that can be conditioned by habitat, environmental and/or physiological factors.

n_agents

Integer, the number of agents to track within the simulation.

ref_sys

Object of class <crs>, defining the Coordinate Reference System to be applied to the IBM. Must be specified via sf::st_crs().

aoc_bbx

Object of class <bbox>, specifying the area of calculation (AOC), i.e. the spatial bounding box within which simulation occurs.

delta_x,delta_y

Numeric, specifying the cell (pixel) size in the x and y dimensions, respectively. These define the spatial resolution of the AOC. Required only when movement_model = "crw"; otherwise values are automatically derived from the resolution of provided density maps. Units are assumed to match those of ref_sys.

delta_time

Character string, defines the temporal resolution of the model. Valid options include "hours", "day", "week", "month" or "year", and can be preceded by a positive integer and a space, and followed by "s".

start_date;end_date

Date, respectively, defines the start and end dates for the simulation period.

start_sites

An <sf> object, defining the sites where agents start the simulation. Apart from the sites' geometry, this object must contain the following columns:

  • id: a unique identifier for each site.

  • prop: the proportion of n_agents allocated at each site. The values in this column must sum to 1.

If start_sites are not provided, agents start at random locations within the AOC.

end_sites

An <sf> object, analogous to start_sites, but specifying the sites to which agents must return to at the end of the simulation. If NULL (the default), end locations are not forced upon agent. Note: This parameter is currently inactive and will be ignored.

See also

ModelConfig() for creating <ModelConfig> objects and further details on the specification of input values.