Check for inconsistent vector indexing methods

R2026b

mathworks.hism.hisl_0021

Dependencies: Simulink^® Check™

Usage: High-Integrity System Modeling

Guideline: hisl_0021: Consistent vector indexing method

Description

This check identifies blocks with inconsistent indexing methods.

Using inconsistent block indexing methods can lead to modeling errors. Use a consistent vector indexing method across all blocks. The supported indexing methods are zero‑based and one‑based indexing.

Elements under review:

• Check use of multiple indexing methods

  • Assignment block

  • For Iterator block

  • Index Vector block

  • Multiport Switch block

  • Selector block

  • Find Nonzero Elements block

• Use Zero-based indexing only

  • Stateflow Chart (Stateflow) with C action language

  • Truth Table (Stateflow) function with C action language

  • State Transition Table (Stateflow) with C action language

• Use One-based indexing only

  • Fcn (deprecated)

  • MATLAB Function block

  • MATLAB System block

  • State Transition Table (Stateflow) with MATLAB^® action language

  • Test Sequence (Simulink Test) block

  • Stateflow Chart (Stateflow) with MATLAB action language

  • Truth Table (Stateflow) function with MATLAB action language

Check Parameters

Use the Model Advisor Configuration Editor to define the scope of the analysis by specifying the input parameters.

Parameter	Description
Check behavior	Specify the type of indexing the blocks support. Check use of multiple indexing methods (default) | Use Zero-based indexing only | Use One-based indexing only Check use of multiple indexing methods — Check analysis includes blocks that support configurable indexing. These blocks support configurable indexing: Assignment For Iterator Index Vector Multiport Switch Selector Find Nonzero Elements Use Zero-based indexing only — Check analysis includes blocks that support only zero-based indexing. These blocks support zero-based indexing: Stateflow Chart (Stateflow) with C action language Truth Table (Stateflow) function with C action language State Transition Table (Stateflow) with C action language Use One-based indexing only — Check analysis includes blocks that support only one-based indexing. These blocks support one-based indexing: Fcn (deprecated) MATLAB Function MATLAB System State Transition Table (Stateflow) with MATLAB action language Test Sequence (Simulink Test) Stateflow Chart (Stateflow) with MATLAB action language Truth Table (Stateflow) function with MATLAB action language
Follow links	Specify whether to include content of library-linked blocks in the analysis. on (default) | off
Look under masks	Specify whether to include masked model elements in the analysis. all (default) | none | graphical | functional all — Check analysis includes all masked model elements. none — Check analysis excludes masked model elements. graphical — Check analysis includes only the graphical masked model elements. functional — Check analysis includes only the functional masked model elements.

Recommended Actions and Results

Review the violations that are flagged by the check and the recommended action for fixing the issue. After applying the changes, save the model and rerun the check analysis.

Modeling Condition	Recommended Action
The model or subsystem contains blocks with inconsistent indexing methods. The indexing methods are zero-based, one-based, or user-specified.	Modify the model to use a single consistent indexing method.

Capabilities and Limitations

• Runs on library models

• Does not require model compilation

• Allows exclusions of blocks and charts

• Analyzes both active and inactive variant choices

Version History

Introduced in R2018b