addevent

Add event to model

Syntax

eventObj = addevent(modelObj, 'TriggerValue', 'EventFcnsValue')
eventObj = addevent(...'PropertyName', PropertyValue...)


Arguments

modelObj	Model object.
TriggerValue	Required property to specify a trigger condition. Must be a MATLAB® expression that evaluates to a logical value. Use the keyword 'time' to specify that an event occurs at a specific time during the simulation. For more information, see Trigger.
EventFcnsValue	Character vector or a cell array of character vectors, each of which specifies an assignment of the form 'objectname = expression', where objectname is the name of a valid object. Defines what occurs when the event is triggered. For more information, see EventFcns.
PropertyName	Property name for an event object from Property Summary.
PropertyValue	Property value. For more information on property values, see the property reference for each property listed in Property Summary.

Description

eventObj = addevent(modelObj, 'TriggerValue', 'EventFcnsValue') creates an Event object (eventObj) and adds the event to the model (modelObj). In the event object, this method assigns a value (TriggerValue) to the property TriggerCondition, assigns a value (EventFcnsValue) to the property EventFcns, and assigns the model object (modelObj) to the property Parent. In the model object, this method appends the event object to the property Events.

When the trigger expression in the property Trigger changes from false to true, the assignments in EventFcns are executed during simulation.

For details on how events are handled during a simulation, see Events in SimBiology Models.

eventObj = addevent(...'PropertyName', PropertyValue...) defines optional properties. The property name and property value pairs can be any format supported by the function set.

Property Summary

Type	Display SimBiology object type
UserData	Specify data to associate with object

Examples

Add an Event

Create a simple model with a mass action reaction A -> B, where A and B are species. Also add the reaction rate parameter, p1, with a parameter value of 0.5.

model       = sbiomodel('example');
r1          = addreaction(model,'A -> B');
kl          = addkineticlaw(r1,'MassAction');
p1          = addparameter(model,'p1',0.5);
kl.ParameterVariableNames = 'p1';

Increase the amount of species A to 100 at time = 2. You can do this by adding an event object to the model. You must specify the event trigger (time >= 2), and also the event function, which defines what happens when the event is triggered. In this example, the event function is A = 100.

e1 = addevent(model,'time>=2','A = 100');

Simulate the model, and plot the result.

sd = sbiosimulate(model);
sbioplot(sd);

Version History

Introduced in R2007b

R2024a: Having duplicate model component names is no longer allowed

• When you load a model that contains duplicate names, SimBiology^® automatically updates those names. SimBiology disambiguates the duplicate names by adding a suffix "_N", where N is the first positive integer that results in a unique name. If there is an existing suffix, N will be incremented from that suffix. For example, if there are two model components named x_3, the function updates one of the names to x_4. If the existing suffix has leading zeros, the function omits the zeros in the new name. For instance, if x_003 is a duplicate name, it gets renamed to x_4. However, the function assumes that names with leading zeros and without leading zeros are different. For instance, x_005 and x_5 are considered to be different names.

• SimBiology issues an error if multiple model components (model, compartment, species, parameter, reaction, rule, event, observable, dose, and variant) have the same name. Within a single model, these components are required to have unique names even when they are of different types with the following two exceptions:

  • Species in different compartments can have the same name.

  • Parameters can have the same name if they are scoped to different parents. Specifically, you can use the same name for a model-scoped parameter and reaction-scoped parameters, where each reaction-scoped parameter belongs to a different reaction.

  For details on how to reference model component names in expressions, see Guidelines for Referencing Names in Expressions.

R2022b: Having duplicate model component names issues a warning

SimBiology issues a warning if multiple model components have the same name.

R2022a: Having duplicate model component names will not be allowed in a future release

SimBiology will not allow you to have duplicate names for model components within a model.