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simulation

Syntax

simulation { ... }

Description

Declares a simulation block. The simulation block defines the core properties of the simulation, including the simulation locations and time frame (start and end dates). The simulation block is required.

A minimal simulation block defines the locations and start_date for the simulation. The length of the simulation is specified using either a end_date statement or an explicit number of days.

Additional simulation settings control the random number seed for the simulation and several properties controlling the output of the simulation. These are described in the FRED Language Guide, or through the See Also references on this page.

Examples

Here is a basic simulation block defining a single location and a year-long simulation.

simulation {
    locations = Pittsburgh_PA
    start_date = 2020-Jan-01
    end_date = 2020-Dec-31
}

The simulation block can also select the initial seed for the random number generator. The block may also set the maximum number of transition steps an agent may perform at a given time step, to help avoid infinite loops. These settings are not usually modified by users, and are shown in the following example.

simulation {
    locations = Pittsburgh_PA
    start_date = 2020-Jan-01
    days = 365

    seed = 123456
    max_loops = 1000000
}

See Also