simList-accessors-times: Time usage in 'SpaDES'

In PredictiveEcology/SpaDES.core: Core Utilities for Developing and Running Spatially Explicit Discrete Event Models

Time usage in SpaDES

Description

Functions for the simtimes slot of a simList object and its elements. To maintain modularity, the behaviour of these functions depends on where they are used. In other words, different modules can have their own timeunit. SpaDES converts these to seconds when running a simulation, but shows the user time in the units of the model as shown with timeunit(sim)

Usage

times(x, ...)

## S4 method for signature 'simList'
times(x)

times(x) <- value

## S4 replacement method for signature 'simList'
times(x) <- value

## S3 method for class 'simList'
time(x, unit, ...)

time(x) <- value

## S4 replacement method for signature 'simList'
time(x) <- value

end(x, ...)

## S3 method for class 'simList'
end(x, unit, ...)

end(x) <- value

## S4 replacement method for signature 'simList'
end(x) <- value

start(x, ...)

## S3 method for class 'simList'
start(x, unit = NULL, ...)

start(x) <- value

## S4 replacement method for signature 'simList'
start(x) <- value

timeunit(x)

## S4 method for signature 'simList'
timeunit(x)

timeunit(x) <- value

## S4 replacement method for signature 'simList'
timeunit(x) <- value

timeunits(x)

## S4 method for signature 'simList'
timeunits(x)

elapsedTime(x, ...)

## S3 method for class 'simList'
elapsedTime(x, byEvent = TRUE, units = "auto", ...)

Arguments

x	A simList
...	Additional parameters.
value	A time, given as a numeric, optionally with a unit attribute, but this will be deduced from the model time units or module time units (if used within a module).
unit	Character. One of the time units used in SpaDES.
byEvent	Logical. If TRUE, the elapsed time will be by module and event; FALSE will report only by module. Default is TRUE.
units	character string. Units in which the results are desired. Can be abbreviated.

Details

timeunit will extract the current units of the time used in a simulation (i.e., within a spades call). If it is set within a simInit, e.g., times=list(start=0, end=52, timeunit = "week"), it will set the units for that simulation. By default, a simInit call will use the smallest unit contained within the metadata for the modules being used. If there are parent modules, then the parent module timeunit will be used even if one of its children is a smaller timeunit. If all modules, including parents, are set to NA, timeunit defaults to seconds. If parents are set to NA, then the set of modules defined by that parent module will be given the smallest units of the children.

Currently, available units are "second", "hours", day", "week", "month", and "year" can be used in the metadata of a module.

The user can also define a new unit. The unit name can be anything, but the function definition must be of the form dunitName, e.g., dyear or dfortnight. The unit name is the part without the d and the function name definition includes the d. This new function, e.g., dfortnight <- function(x) lubridate::duration(dday(14)) can be placed anywhere in the search path or in a module.

timeunits will extract the current units of the time of all modules used in a simulation. This is different from timeunit because it is not necessarily associated with a spades call.

In many cases, the "simpler" use of each of these functions may be slower computationally. For instance, it is much faster to use time(sim, "year") than time(sim). So as a module developer, it is advantageous to write out the longer one, minimizing the looking up that R must do.

Value

Returns or sets the value of the slot from the simList object.

Note

These have default behaviour that is based on the calling frame timeunit. When used inside a module, then the time is in the units of the module. If used in an interactive mode, then the time will be in the units of the simulation.

Additional methods are provided to access the current, start, and end times of the simulation:

time	Current simulation time.
start	Simulation start time.
end	Simulation end time.
timeunit	Simulation timeunit.
timeunits	Module timeunits.
times	List of all simulation times (current, start, end, timeunit).

Author(s)

Alex Chubaty and Eliot McIntire

See Also

SpaDES.core-package, specifically the section 1.2.5 on Simulation times; elapsedTime(),

Other functions to access elements of a 'simList' object: .addDepends(), checkpointFile(), envir(), events(), globals(), inputs(), modules(), objs(), packages(), params(), paths(), progressInterval()

Examples

# Elapsed Time
s1 <- simInit()
s2 <- spades(s1)
elapsedTime(s2)
elapsedTime(s2, units = "mins")

PredictiveEcology/SpaDES.core documentation built on April 17, 2024, 8:27 a.m.