sdo.requirements.RelationalConstraint Class

Namespace: sdo.requirements
Superclasses:

Impose relational constraint on pair of variables

Description

Use the sdo.requirements.RelationalConstraint object to impose a relational constraint on a pair of variables in a Simulink^® model. The variables can be any parameters in your model. You create the requirement object, and specify the type of relation you want between the elements of the two variables. For example, for two variables var1 and var2, you can specify that each element of var1 be greater than the corresponding element of var2.

You can use the requirement object as an input to your cost function and use the evalRequirement command to evaluate if your test data satisfies the specified requirement. You can then use the cost function and sdo.optimize to perform response optimization, subject to satisfaction of the specified requirement. If you are performing sensitivity analysis, after you generate parameter samples, you can use the cost function and sdo.evaluate to evaluate the requirement for each generated sample.

Construction

rel_req = sdo.requirements.RelationalConstraint creates an sdo.requirements.RelationalConstraint requirement object and assigns default values to its properties. Use dot notation to customize the properties. Use the evalRequirement command to evaluate if test data satisfies the specified requirement.

rel_req = sdo.requirements.RelationalConstraint(Name=Value) specifies one or more properties using name-value arguments. For example, rel_req = sdo.requirements.RelationalConstraint(Type=">") creates an sdo.requirements.RelationalConstraint object and specifies that each data element in the first variable is strictly greater than the corresponding element in the second variable.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes. For example, rel_req = sdo.requirements.RelationalConstraint("Type",">") creates an sdo.requirements.RelationalConstraint object and specifies that each data element in the first variable is strictly greater than the corresponding element in the second variable.

Properties

Description — Requirement description

'' (default) | character vector

Requirement description, specified as a character vector.

Example: 'Requirement 1 for myModel.'

Data Types: char

Name — Name of requirement

'' (default) | character vector

Name of requirement, specified as a character vector.

Example: 'Requirement1'

Data Types: char

Type — Relation type

'<' (default) | '<=' | '>' | '>=' | '==' | '~='

Relation type between the elements of the two variables, specified as one of the following:

• '<' — Each data element in the first variable is less than the corresponding element in the second variable.

• '<=' — Each data element in the first variable is less than or equal to the corresponding element in the second variable.

• '>' — Each data element in the first variable is greater than the corresponding element in the second variable.

• '>=' — Each data element in the first variable is greater than or equal to the corresponding element in the second variable.

• '==' — Each data element in the first variable is equal to the corresponding element in the second variable.

• '~=' — Each data element in the first variable is not equal to the corresponding element in the second variable.

Data Types: char

Methods

copy	Copy design requirement
get	Get design requirement property values
set	Set design requirement property values
evalRequirement	Evaluate design requirement

Copy Semantics

Handle. To learn how handle classes affect copy operations, see Copying Objects.

Examples

Constrain One Variable to be Greater Than Another

Create a requirement object with default properties to define the relation between two variables.

Requirement = sdo.requirements.RelationalConstraint;

Specify that the elements of the first variable be greater than the elements of the second variable.

Requirement.Type = '>';

You can now use the evalRequirement command to evaluate whether test data from two variables satisfy the requirement.

Constrain Two Variables to be Equal to Each Other

Create a requirement object, and specify the relation between two variables in your model.

Requirement = sdo.requirements.RelationalConstraint('Type','==');

The elements of the first variable are required to be equal to the corresponding elements of the second variable.

Version History

Introduced in R2016b