Model and Validate Requirements

Model requirements and analyze for consistency and completeness by using 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 by using programmatic commands in MATLAB^®.

Confirm that your requirements are complete and consistent by analyzing your formal requirements using Simulink Design Verifier™. Validate formal requirements before generating tests and verifying specification models.

You can also verify requirements in Requirements Table blocks by generating tests. For more information, see Verify Requirements by Using Tests.

Blocks

Requirements Table

Model formal requirements with input conditions (Since R2022a)

Functions

expand all

Requirements Table Block Functions

`slreq.modeling.create`	Create new model with Requirements Table block (Since R2022a)
`slreq.modeling.find`	Find Requirements Table blocks (Since R2022a)
`slreq.load`	Load requirement set, link set, or Requirements Table block
`anyValue`	Suppress incompleteness issues for output in Requirements Table block (Since R2024a)

Operators

expand all

Requirements Table Block Operators

Temporal Logic

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

Change Detection

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

Create, Concatenate, and Convert Strings

`str2double`	Convert string to double-precision value in Requirements Table block
`string`	Convert value to string in Requirements Table block
`plus`	Concatenate strings in Requirements Table block

Determine Properties of Strings

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

Find and Replace String Characters

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

Edit Strings

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

Compare Strings

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

Objects

expand all

Requirements Table Block Objects

`RequirementsTable`	Configure Requirements Table blocks (Since R2022a)
`Symbol`	Configure data in Requirements Table blocks (Since R2022a)
`RequirementRow`	Requirements in Requirements Table block (Since R2022a)
`AssumptionRow`	Assumptions in Requirements Table block (Since R2022a)

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

Topics

Create Requirements

Use a Requirements Table Block to Create Formal Requirements
Assess formal requirements by using Requirements Table blocks. (Since R2022a)
Construct Specification Models by Using Requirements Table Blocks
Learn about specification models and how to use them for requirements-based verification. (Since R2022b)
Add Assumptions to Requirements
Use assumptions to constrain formal requirement data in Requirements Table blocks according to physical limitations. (Since R2022a)
Specify Row Type in Requirements Table Blocks
Define the row types for requirements and assumptions in a Requirements Table block. (Since R2022a)
Create Requirements Table Blocks Programmatically
Create and modify Requirements Table blocks from the MATLAB command line. (Since R2022a)
Control Requirement Execution by Using Temporal Logic
Use temporal logic operators to control requirement evaluation and execution. (Since R2022a)

Define Evaluation Logic

Establish Hierarchy in Requirements Table Blocks
Establish parent-child relationships between requirements or assumptions. (Since R2022a)
Specify Child Evaluation in Requirements Table Blocks

Specify how the block evaluates requirements at each level of the hierarchy in the Requirements Table. (Since R2023b)
- Create Prioritized Requirements
- Create Exclusive Exhaustive Requirements
Leverage Evaluation Order of Formal Requirements
Specify the order of evaluation in a Requirements Table block. (Since R2022a)
Detect Read-Before-Write Issues
Use Simulink Design Verifier to detect read-before-write issues in Requirements Table blocks. (Since R2022a)

Configure Properties of Requirements Table Blocks

Configure Properties of Formal Requirements
Modify the type, description, or rationale for each requirement in a Requirements Table block. (Since R2022a)

Configure Data

Define Data in Requirements Table Blocks
Add or modify data in a Requirements Table block. (Since R2022a)
Set Data Types in Requirements Table Blocks
Specify the data types to use in your formal requirements. (Since R2022a)
Specify Size of Requirements Table Block Data
Specify data sizes in a Requirements Table block. (Since R2022a)
Detect Data Changes by Using Requirements Table Blocks
Execute formal requirements when data changes between time steps. (Since R2022a)

Validate Requirements

Analyze Requirements Table Blocks for Modeling Problems
Use Simulink Design Verifier to validate Requirements Table blocks. (Since R2022a)
Identify Inconsistent and Incomplete Formal Requirement Sets
Use Simulink Design Verifier to find inconsistent and incomplete requirement sets. (Since R2022a)
Detect Exclusivity Issues in the Requirements Table Block
Use Simulink Design Verifier to identify issues with exclusive exhaustive child requirements. (Since R2023b)

Troubleshooting

Debug Requirements Table Blocks

Debug Requirements Table blocks by using breakpoints and analyzing block data during simulation. (Since R2023a)

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.

Since R2022a
Open Model

Define Formal Requirements with a Duration

Define formal requirements that use a duration.

Since R2022a
Open Live Script

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.