modelLogisticGrowth

S-shaped logistic growth process

Extends from Interfaces.PartialCLD.SourceOrSink (Partial source or sink for causal loop diagramming).

Information

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Using the →LogisticGrowth component from the SourcesOrSinks package, this component allows to model a process of s-shaped growth given a constant maximum fractional growth rate rate and a constant carrying capacity (carryingCapacity). Instead of using constant parameters, it is also possible to use variable inputs (u_rate, u_K).

The process by default is active over the whole simulation run, but can be restricted to an on-off period using tc = TimingChoices.period and the parameters startTime and stopTime. Any given rate—rate or u_rate—can be modified by multiplication with an optionally given input u.

Implementation

DiagramView
ModelDiagram.png

See also

ExponentialChange, LinearChange

Parameters

TypeNameDefaultDescription
OutputTyperate (from SourceOrSink)unspecifiedConstant rate (optional)
CapacityTypecarryingCapacityCarrying capacity
Structural Parameters
BooleanhasRateOutput (from FlowPort)false= true, if the rate is reported via real output connectors
BooleanhasConstantRate (from SourceOrSink)true= true, if rate is a constant parameter
BooleanhasFactor (from SourceOrSink)false= true, if rate is to be multiplied with input u
BooleanhasConstantCapacitytrue= true, if the carrying capacity given is given by a constant parameter
BooleanisCCRtrue= true, if the factional rate given is assumed to be a continuously compounding rate else the rate will be converted
Timing
TimingChoicestc (from TimedSource)TimingChoices.permanentSelect whether contoll is permanent or timed
TimeonTime (from TimedSource)modelSettings.modelStartTimeTime for component to become effective
TimeoffTime (from TimedSource)modelSettings.modelTimeHorizonTime for component to become ineffective

Connectors

TypeNameDefaultDescription
FlowPortflowPort (from FlowPort)Used to represent stock and flow connections
RealInputu (from SourceOrSink)Factor input
RealInputu_rate (from SourceOrSink)Rate input
Interfaces.Connectors.RealInputu_KCarrying capacity

Components

TypeNameDefaultDescription
RealOutputy (from FlowPort)Output of current rate of flow
RealOutputy1 (from FlowPort)Output of current rate of flow
ModelSettingsmodelSettings (from TimedSource)

Contents

NameDescription
CapacityType

Revisions

  • Introduced in v2.0.0.