Simulink Reference

Model Parameters

This table lists and describes parameters that describe a model. The parameters appear in the order they are defined in the model file, described in Model File Format. The table also includes model callback parameters, (see Using Callback Routines). The Description column indicates where you can set the value on the Simulation Parameters dialog box. Model parameters that are simulation parameters are described in more detail in The Simulation Parameters Dialog Box. Examples showing how to change parameters follow the table.

Parameter values must be specified as quoted strings. The string contents depend on the parameter and can be numeric (scalar, vector, or matrix), a variable name, a filename, or a particular value. The Values column shows the type of value required, the possible values (separated with a vertical line), and the default value, enclosed in braces.

Table 8-1: Model Parameters

Parameter	Description	Values
AbsTol	Absolute error tolerance	scalar {1e-6}
AlgebraicLoopMsg	Algebraic loop diagnostic	none | {warning} | error
ArrayBoundsChecking	Enable array bounds checking	'none' | 'warning' | 'error'
BooleanDataType	Enable Boolean mode	on | {off}
BufferReuse	Enable reuse of block I/O buffers	{on} | off
CloseFcn	Close callback	command or variable
ConfigurationManager	Configuration manager for this model	text
ConsistencyChecking	Consistency checking	on | {off}
Created	Date and time model was created	text
Creator	Name of model creator	text
Decimation	Decimation factor	scalar {1}
DefaultBlockFontSize	Default font size for blocks contained by this model	{10}
Description	Description of this model	text
ExternalInput	Time and input variable names	scalar or vector [t, u]
FinalStateName	Final state name	variable {xFinal}
FixedStep	Fixed step size	scalar {auto}
InitialState	Initial state name or values	variable or vector {xInitial}
InitialStep	Initial step size	scalar {auto}
InvariantConstants	Invariant constant setting	on | {off}
LimitDataPoints	Limit output	on | {off}
LoadExternalInput	Load input from workspace	on | {off}
LoadInitialState	Load initial state	on | {off}
MaxDataPoints	Maximum number of output data points to save	scalar {1000}
MaxOrder	Maximum order for ode15s	1 | 2 | 3 | 4 | {5}
MaxStep	Maximum step size	scalar {auto}
MinStepSizeMsg	Minimum step size diagnostic	{warning} | error
ModelVersionFormat	Format of model's version number	text
ModifiedBy	Last modifier of this model	text
ModifiedDateFormat	Format of modified date	text
Name	Model name	text
ObjectParameters	Names/attributes of model parameters	structure
OutputOption	Output option	AdditionalOutputTimes | {RefineOutputTimes} | SpecifiedOutputTimes
OutputSaveName	Simulation output name	variable {yout}
OutputTimes	Values for chosen OutputOption	vector {[]}
PaperOrientation	Printing paper orientation	portrait | {landscape}
PaperPosition	Position of diagram on paper	[left, bottom, width, height]
PaperPositionMode	Paper position mode	auto | {manual}
PaperSize	Size of PaperType in PaperUnits	[width height] (read only)
PaperType	Printing paper type	{usletter} | uslegal | a0 | a1 | a2 | a3 | a4 | a5 | b0 | b1 | b2 | b3 | b4 | b5 | arch-A | arch-B | arch-C | arch-D | arch-E | A | B | C | D | E | tabloid
PaperUnits	Printing paper size units	normalized | {inches} | centimeters | points
PostLoadFcn	Post-load callback	command or variable
PreLoadFcn	Preload callback	command or variable
Refine	Refine factor	scalar {1}
RelTol	Relative error tolerance	scalar {1e-3}
SampleTimeColors	Sample Time Colors menu option	on | {off}
SaveFcn	Save callback	command or variable
SaveFinalState	Save final state	on | {off}
SaveFormat	Format used to save data to the MATLAB workspace	Array | Structure | StructureWithTime
SaveOutput	Save simulation output	{on} | off
SaveState	Save states	on | {off}
SaveTime	Save simulation time	{on} | off
ScreenColor	Background color of the model window	black | {white} | red | green | blue | cyan | magenta | yellow | gray | lightBlue | orange | darkGreen
ShowLineWidths	Show Line Widths menu option	on | {off}
SimulationCommand	Executes a simulation command.	start | stop | pause | continue | update
SimParamPage	Simulation Parameters dialog box page to display (page last displayed)	{Solver} | WorkspaceI/O | Diagnostics
Solver	Solver	{ode45} | ode23 | ode113 | ode15s | ode23s | ode5 | ode4 | ode3 | ode2 | ode1 | FixedStepDiscrete | VariableStepDiscrete
StartFcn	Start simulation callback	command or variable
StartTime	Simulation start time	scalar {0.0}
StateSaveName	State output name	variable {xout}
StopFcn	Stop simulation callback	command or variable
StopTime	Simulation stop time	scalar {10.0}
TimeSaveName	Simulation time name	variable {tout}
UnconnectedInputMsg	Unconnected input ports diagnostic	none | {warning} | error
UnconnectedLineMsg	Unconnected lines diagnostic	none | {warning} | error
UnconnectedOutputMsg	Unconnected output ports diagnostic	none | {warning} | error
Version	Simulink version used to modify the model (read-only)	(release)
WideVectorLines	Wide Vector Lines menu option	on | {off}
ZeroCross	Intrinsic zero-crossing detection (see Zero-Crossing Detection)	{on} | off

These examples show how to set model parameters for the mymodel system.

This command sets the simulation start and stop times.

• set_param('mymodel','StartTime','5','StopTime','100')
  

This command sets the solver to ode15s and changes the maximum order.

• set_param('mymodel','Solver','ode15s','MaxOrder','3')
  

This command associates a SaveFcn callback.

• set_param('mymodel','SaveFcn','my_save_cb')
  

Model and Block Parameters

Common Block Parameters