Formalize Requirements in Simulink Models

Evaluate logic before and during simulation with Requirements Table blocks

Define formal requirements in Simulink^® models by using the Requirements Table block to evaluate logic before and at run time. Use formal requirements to check the outputs of your model or execute block outputs.

Configure the formal requirements directly in the block, in the Requirements Editor, or with programmatic commands in MATLAB^®.

Blocks

Requirements Table

Model formal requirements with input conditions

Functions

expand all

Requirements Table Block Functions

`slreq.modeling.create`	Create new model with Requirements Table block
`slreq.modeling.find`	Find Requirements Table blocks
`slreq.load`	Load requirement set or link set

Objects

expand all

Requirements Table Block Objects

`RequirementsTable`	Configure Requirements Table blocks
`Symbol`	Configure data in Requirements Table blocks
`RequirementRow`	Work with requirements in Requirements Table block
`AssumptionRow`	Work with assumptions in Requirements Table block

Object Functions

expand all

Requirements Table Block Object Functions

Manage Block Data

`addSymbol`	Add data to Requirements Table block
`findSymbol`	Retrieve data in Requirements Table block

Manage Block Rows

`addAssumptionRow`	Add assumption to Requirements Table block
`addRequirementRow`	Add requirement to Requirements Table block
`addChild`	Add child requirement or assumption to Requirements Table block
`getRequirementRows`	Retrieve requirements in Requirements Table block
`getAssumptionRows`	Retrieve assumptions in Requirements Table block
`getChildren`	Retrieve child requirements and assumptions in Requirements Table block
`slreq.getCurrentObject`	Get selected objects in Requirements Editor, Requirements Browser, or Requirements Table block
`clear`	Clear row in Requirements Table block
`removeRow`	Remove Requirements Table block row

Manage Block Columns

`hideAssumptionColumn`	Hide Precondition column in Assumptions tab
`hideRequirementColumn`	Hide columns in Requirements tab
`showAssumptionColumn`	Show Precondition column in Assumptions tab
`showRequirementColumn`	Show columns in Requirements tab

Operators

expand all

Requirements Table Block Operators

Temporal Logic

`duration`	Time during which condition is valid
`getPrevious`	Previous value of data
`isStartup`	Whether simulation time is `0`
`t`	Elapsed time of simulation

Change Detection

`hasChanged`	Detect change in data since last time step
`hasChangedFrom`	Detect change in data from specified value
`hasChangedTo`	Detect change in data to specified value

Create, Concatenate, and Convert Strings

`str2double`	Convert string to double-precision value
`string`	Convert value to string
`plus`	Concatenate strings

Determine Properties of Strings

`isletter`	Determine which characters are letters
`isspace`	Determine which characters are spaces
`isstring`	Determine if input is string
`strlength`	Determine length of string
`contains`	Determine if string contains substring

Find and Replace String Characters

`contains`	Determine if string contains substring
`endsWith`	Determine if string ends with substring
`matches`	Determine if two strings match
`replace`	Find and replace substrings
`replaceBetween`	Replace substrings between start and end points
`startsWith`	Determine if string starts with substring
`strfind`	Find substring within a string
`strrep`	Find and replace substrings

Edit Strings

`erase`	Delete substrings within strings
`eraseBetween`	Delete substring between start and end points
`extractAfter`	Extract substring after position
`extractBefore`	Extract substring before position
`insertAfter`	Insert string after substring
`insertBefore`	Insert string before substring
`lower`	Convert string to lowercase
`upper`	Convert a string to uppercase
`reverse`	Reverse order of characters in strings
`strip`	Remove leading and trailing characters from string
`strtrim`	Remove leading and trailing white space from string

Compare Strings

`matches`	Determine if two strings match
`strcmp`	Compare strings (case sensitive)
`strcmpi`	Compare strings (case insensitive)
`strncmp`	Compare first N characters of strings (case sensitive)
`strncmpi`	Compare first N characters of strings (case insensitive)

Topics

Create and Manage Requirements

Use a Requirements Table Block to Create Formal Requirements
Assess formal requirements by using Requirements Table blocks.
Add Assumptions to Requirements
Use assumptions to constrain formal requirement data in Requirements Table blocks according to physical limitations.
Control Requirement Execution by Using Temporal Logic
Use temporal logic operators to control requirement evaluation and execution.
Detect Data Changes by Using Requirements Table Blocks
Execute formal requirements when data changes between time steps.
Establish Hierarchy in Requirements Table Blocks
Create child and semantic requirements to establish relationships between requirements.
Leverage Evaluation Order of Formal Requirements
Specify the order of evaluation in a Requirements Table block.
Configure Properties of Formal Requirements
Modify the type, description, or rationale for each requirement in your Requirements Table block.
Create Requirements Table Blocks Programmatically
Use the MATLAB command line to create and modify Requirements Table blocks.
Specify Requirements Table Block Properties
Configure how a Requirements Table block interfaces with a Simulink model.

Configure Requirement Data

Define Data in Requirements Table Blocks
Add or modify data that establishes formal requirements.
Set Data Types in Requirements Table Blocks
Specify the data types used in formal requirements.
Specify Size of Requirements Table Block Data
Specify data sizes in a Requirements Table block.

Test Model with Requirements

What Is a Specification Model?
Overview of specification model and its use in requirements-based verification.
Export Tests from Models That Contain Requirements Table Blocks with Simulink Design Verifier
Automate test generation and execution by using models that contain Requirements Table blocks.

Troubleshooting

Identify Inconsistent and Incomplete Formal Requirement Sets

Use Simulink Design Verifier™ to find inconsistent and incomplete requirement sets and read-before-write issues.

Debug Requirements Table Blocks

Debug Requirements Table block requirements during simulation.

Featured Examples

Model Dice Game Rules Using a Requirements Table Block

Use a Requirements Table block to model the rules and the game outcome associated with a dice game.

Open Model

Analyze Formal Requirements of an Electric Vehicle Charger Locking Mechanism

Use a Requirements Table block and Simulink Design Verifier to construct, analyze, and update formal requirements of an electric vehicle charging station locking mechanism.

Open Live Script

Define Formal Requirements with a Duration

Define formal requirements that use a duration.

Open Live Script

Use Specification Models for Requirements-Based Testing

Follow a systematic approach to verify your design model against requirements.

Open Live Script

Prove Properties with Requirements Table Blocks

Use a Requirements Table block and Simulink Design Verifier to prove properties of a model.

Open Model