Simulink.ValueType - Specify common set of signal properties for reuse - MATLAB (original) (raw)

Specify common set of signal properties for reuse

Since R2021b

Description

A Simulink.ValueType object is a common set of signal properties that you define once and reuse for each signal that represents the same value type. For example, you can specify the unit, minimum value, maximum value, and dimensions of wind velocity, tire pressure, or water temperature once and reuse that specification.

To create and modify Simulink.ValueType objects in the base workspace or a data dictionary, you can use the Type Editor, Model Explorer, or MATLAB® commands. You cannot store Simulink.ValueType objects in model workspaces.

Use a Simulink.ValueType object to specify signal properties for these blocks and objects:

Inport block
Outport block
In Bus Element block
Out Bus Element block
Signal Specification block
Constant block (since R2023b)
Simulink.BusElement objects
Simulink.Signal objects (since R2023a)
Simulink.Parameter objects (since R2023a)

Use Simulink.ValueType objects to validate the properties of a signal and enforce consistency between connected blocks at an interface.

Creation

You can create a Simulink.ValueType object several ways.

Interactively create a value type using the Type Editor orModel Explorer.
Programmatically create a value type using the Simulink.ValueType function described here.

Syntax

Description

`vt` = Simulink.ValueType returns aSimulink.ValueType object with default property values.

example

Properties

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Data type, specified as a character vector or string scalar.

You can specify any of these options:

Built-in Simulink® data type — For example, specify 'single' or'uint8'. See Data Types Supported by Simulink.
Fixed-point data type — Use the fixdt function. For example, specify 'fixdt(1,16,0)'.
Enumerated data type — Use the name of the type preceded byEnum:. For example, specify 'Enum: myEnumType'.
Custom data type — Use a MATLAB expression that specifies the type. For example, you can specify aSimulink.NumericType object whoseDataTypeMode property is set to a value other than'Fixed-point: unspecified scaling'.
Bus data type — Use the name of a Simulink.Bus object preceded byBus:. For example, specify 'Bus: myBusObject'.

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

Data Types: char | string

Minimum value, specified as a finite real double scalar.

Dependencies

The software ignores the value of this property when DataType specifies a Simulink.Bus object. The software uses the minimum values specified by the Simulink.BusElement objects in theSimulink.Bus object instead.

Data Types: double

Maximum value, specified as a finite real double scalar.

Dependencies

The software ignores the value of this property when DataType specifies a Simulink.Bus object. The software uses the maximum values specified by the Simulink.BusElement objects in theSimulink.Bus object instead.

Data Types: double

Physical unit, specified as a character vector or string scalar.

For more information, see Unit Specification in Simulink Models.

Example: 'inches'

Dependencies

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

Data Types: char | string

Numeric type, specified as 'real' or'complex'.

Dependencies

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

Data Types: char | string

Dimensions, specified as a scalar or vector.

Tips

To specify an array of buses, set DataType to aSimulink.Bus object and Dimensions to the dimensions of the array.

Data Types: double

Option to allow only fixed-size or variable-size signals, specified as'Fixed' or 'Variable', respectively.

Dependencies

The software ignores the value of this property when DataType specifies a Simulink.Bus object. The software uses the dimensions modes specified by the Simulink.BusElement objects in theSimulink.Bus object instead.

Data Types: char | string

Description, specified as a character vector or string scalar. Use the description to document information about the Simulink.ValueType object, such as the kind of signal it applies to. This information does not affect Simulink processing.

Data Types: char | string

Examples

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In the MATLAB Command Window, define a reusable set of properties that correspond to wind velocity by using the Simulink.ValueType function.

Create a ValueType object with default properties.

windVelocity = Simulink.ValueType

windVelocity = ValueType with properties:

      DataType: 'double'
           Min: []
           Max: []
          Unit: ''
    Complexity: 'real'
    Dimensions: 1
DimensionsMode: 'Fixed'
   Description: ''

Specify the desired property values for wind velocity.

windVelocity.DataType = 'single'; windVelocity.Min = 11; windVelocity.Max = 17; windVelocity.Unit = 'm/s'; windVelocity.Dimensions = [2 4 3]; windVelocity.Description = 'Wind velocity value type'

windVelocity = ValueType with properties:

      DataType: 'single'
           Min: 11
           Max: 17
          Unit: 'm/s'
    Complexity: 'real'
    Dimensions: [2 4 3]
DimensionsMode: 'Fixed'
   Description: 'Wind velocity value type'

To define a recurring type of value that you model as an array of buses, use a Simulink.ValueType object with a Simulink.Bus object data type and nonscalar dimensions.

Create a Simulink.Bus object that represents red, green, and blue (RGB) color values. Name it RGB.

r = Simulink.BusElement; r.Name = 'r';

g = Simulink.BusElement; g.Name = 'g';

b = Simulink.BusElement; b.Name = 'b';

RGB = Simulink.Bus; RGB.Elements = [r g b];

Create a Simulink.ValueType object that represents an image. Name it myImage.

myImage = Simulink.ValueType;

Assign the bus object named RGB as the data type of myImage.

myImage.DataType = 'Bus: RGB';

Specify that the value type represents a matrix of RGB values by setting the dimensions of myImage to a matrix.

myImage.Dimensions = [1024 1024];

When you use the myImage value type in a model, it defines an array of buses. For more information about arrays of buses, see Group Nonvirtual Buses in Arrays of Buses.

Version History

Introduced in R2021b