Simulink.Parameter

Value to use in block parameters, specified as any of these valid values:

If you use a Simulink.Parameter object to set the block parameter value in a reusable referenced model, you can compile and simulate the model as a referenced model with the value for the object left empty (Value set to []) as long as you provide an explicit value somewhere in the parent model reference hierarchy. In this case, you cannot simulate the model directly. When the value is empty, you must provide the DataType and Dimensions for the object. Although you have specified an empty value, the software still synthesizes a Value by using one of these:

See Configure Instance-Specific Values for Block Parameters in a Referenced Model.

You can also use MATLAB^® syntax to specify the value.

To use a Simulink.Parameter object to store a value of a particular numeric data type, specify the ideal value with the Value property and control the data type with the DataType property.

If you set the Value property by using a typed expression such as single(32.5), the DataType property changes to reflect the new type. A best practice is to use an expression that is not typed to avoid accumulating numerical error through repeated quantizations or data type saturation, especially for fixed-point data types.

If you set the Simulink.Parameter object Value as a string or character value, Value is stored as a MATLAB string. For limitations on strings as Simulink.Parameter object values, see Simulink.Parameter in Simulink String Limitations.

Example: 3.15

Example: "mystring"

Example: 1.2 + 3.2i

Example: true

Example: myEnumType.myEnumValue

Example: struct('field1',15,'field2',7.32)

Example: slexpr('myVar + myOtherVar')

Tips

Data Types: double | single | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | logical | struct | fi | enum | string
Complex Number Support: Yes

This property is read-only.

Specifications for generating code for the parameter object, returned as a Simulink.CoderInfo object.

Modify the properties of the Simulink.CoderInfo object that this property contains.

For example, the StorageClass property of the Simulink.CoderInfo object determines how Simulink^® code generation toolboxes allocate memory for the parameter object in the generated code. For more information, see C Data Code Interface Configuration for Model Interface Elements (Simulink Coder) and Choose Storage Class for Controlling Data Representation in Generated Code (Embedded Coder).

Custom description of the parameter object, specified as a character vector. Use this property to document the significance that the parameter object has in your algorithm.

If you have an Embedded Coder^® license, you can configure this description to appear in the generated code as a comment. See Simulink data object descriptions (Embedded Coder).

Example: 'This parameter represents the maximum rotation speed of the engine.'

Data Types: char | string

Data type of the parameter value in the Value property, specified as 'auto' or a character vector. When you simulate the model or generate code, the software casts the value to the specified data type.

If you specify 'auto', the default setting, the parameter object uses the same data type as the block parameters that use the object. See Reduce Maintenance Effort with Data Type Inheritance.

When you set the Value property to something other than a double number, the object typically sets the DataType property based on the value of the Value property. For example, when you set the Value property to int8(5), the object sets the value of the DataType property to 'int8'.

To explicitly specify a built-in data type (see Data Types Supported by Simulink), specify one of these options:

To specify a fixed-point data type, use the fixdt function. For example, specify 'fixdt(1,16,5)'.

If you use a Simulink.AliasType or Simulink.NumericType object to create and share custom data types in your model, specify the name of the object.

To specify an enumerated data type, use the name of the type preceded by Enum:. For example, specify 'Enum: myEnumType'.

To specify a Simulink.ValueType object as the data type, use the name of the object preceded by ValueType:. For example, specify 'ValueType: myValueType'.

When you store a structure or array of structures in the Value property of the object, the object sets the DataType property to 'struct'. To specify a Simulink.Bus object as the data type, use the name of the bus object preceded by Bus:. For example, specify 'Bus: myBusObject'.

If you set the Simulink.Parameter object Value as a string, note the limitations in Simulink String Limitations.

When you specify a Simulink.ValueType or Simulink.Bus object as the data type, some properties of the Simulink.Parameter object are ignored. For example, the Min, Max, and Unit properties of the Simulink.Parameter object are ignored. The software uses the corresponding properties of the Simulink.ValueType object or Simulink.BusElement objects in the Simulink.Bus object instead.

Example: 'auto'

Example: 'int8'

Example: 'fixdt(1,16,5)'

Example: 'myAliasTypeObject'

Example: 'string'

Example: 'Enum: myEnumType'

Example: 'ValueType: myValueType'

Example: 'Bus: myBusObject'

Tips

When you edit the data type interactively, to display the Data Type Assistant, click the Show data type assistant button . For more information, see Specify Data Types Using Data Type Assistant.

Data Types: char | string

Minimum value that the Value property of the object can store, specified as a real double scalar.

The default value is empty, which means the parameter value does not have a minimum.

If you store a complex number in the Value property, the Min property applies separately to the real and imaginary parts.

If Value is less than the minimum value or if the minimum value is outside the range of the object data type, the software generates a warning. When updating the diagram or starting a simulation, the software generates an error.

For more information about how the software uses this property, see Specify Minimum and Maximum Values for Block Parameters

Example: -0.92

Dependencies

The software ignores the value of this property when either of these options apply:

Tips

For parameter objects with a fixed-point data type, dialog boxes show the stored integer Minimum property, which is the minimum value that the parameter can have, specified as a stored integer value. The value is derived from the real-world minimum value.

Data Types: double

Maximum value that the Value property of the object can store, specified as a real double scalar.

The default value is empty, which means the parameter value does not have a maximum.

If you store a complex number in the Value property, the Max property applies separately to the real and imaginary parts.

If Value is greater than the maximum value or if the maximum value is outside the range of the object data type, the software generates a warning. When updating the diagram or starting a simulation, the software generates an error.

For more information about how the software uses this property, see Specify Minimum and Maximum Values for Block Parameters.

Example: 5.32

Dependencies

The software ignores the value of this property when either of these options apply:

Tips

For parameter objects with a fixed-point data type, dialog boxes show the stored integer Maximum property, which is the maximum value that the parameter can have, specified as a stored integer value. The value is derived from the real-world maximum value.

Data Types: double

Physical unit of parameter value, specified as a character vector that describes a valid unit. For more information, see Unit Specification in Simulink Models.

Example: 'degC'

Dependencies

The software ignores the value of this property when DataType specifies a Simulink.ValueType or Simulink.Bus object. The software uses the units specified by the Simulink.ValueType object or the Simulink.BusElement objects in the Simulink.Bus object instead.

Data Types: char | string

Numeric complexity of the parameter value, specified as either 'real' or 'complex'. For Simulink.Parameter objects in the model workspace, use this property to configure the complexity of a model argument. See Configure Instance-Specific Values for Block Parameters in a Referenced Model.

For numeric values, the software derives the complexity from the parameter value that you specify in the Value property. In this case, changing the complexity results in error.

Dependencies

The software ignores the value of this property when any of these options apply:

Dimensions of the value stored in the Value property, specified as a row vector, character vector, or string scalar.

When you set the Value property of the object, the object sets the value of the Dimensions property to a double row vector. The vector is the same vector that the size function returns.

If you are configuring the object as a model argument, and you intend to provide a value for the object elsewhere in the parent model reference hierarchy, you can leave the Value property empty (set to []) and set the Dimensions and Data Type properties explicitly. See Configure Instance-Specific Values for Block Parameters in a Referenced Model.

To use symbolic dimensions, specify a character vector. See Implement Symbolic Dimensions for Array Sizes in Generated Code (Embedded Coder).

Example: [1 3]

Example: '[1 myDimParam]'

Dependencies

Data Types: double | char | string