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Check usage of Lookup Tables

Check ID: mathworks.jmaab.jc_0626

Guideline: jc_0626: Usage of Lookup Table blocks

Description

Checks for the correct parameter settings in Lookup Tables to prevent unexpected results.

Checks n-D Lookup (1-D,2-D, and n-D) tables for the following parameters to ensure that the values adhere to the corresponding recommendations.

  • InterpMethod

  • ExtrapMethod

  • UseLastTableValue

Checks Dynamic Lookup Tables for the parameter LookUpMeth and ensures that the values adhere to the recommendation.

This check requires a Simulink® Check™ license.

Check Parameterization

This check contains sub-checks that correspond to sub IDs specified in the MAB and JMAAB modeling guidelines. You can use the Model Advisor Configuration Editor to specify which sub IDs (one or multiple) to execute.

For reference, the MAB guideline sub ID(s) that are recommended for use by the NA-MAAB and JMAAB modeling standards organizations are:

  • NA-MAAB — a, b

  • JMAAB — a, b

Results and Recommended Actions

Guideline Sub IDConditionRecommended Action
jc_0626_a: Check Lookup Method settings for Dynamic Lookup table blocksThe parameter Lookup Method in the dynamic lookup table is set to other than Interpolation-Use End Values.Set the parameter to the recommended value Interpolation-Use End Values.
jc_0626_b: Check Lookup Method settings for n-D Lookup table blocksThe parameter Interpolation method in the n-D lookup table is not set to Linear point-slope or Linear Lagrange.

Update the parameter settings with one of the following recommended values

  • Linear point-slope

  • Linear Lagrange

The parameter Extrapolation method in the n-D lookup table is set to Cubic spline or Linear.Set the parameter to the recommended value Clip.
The parameter Use last table value for inputs at or above last breakpoint in the n-D lookup table is set to off.Set the parameter to the recommended value on.

Capabilities and Limitations

  • Analyzes content of library-linked blocks. By default, the input parameter Follow links is set to on.

  • Analyzes content in masked subsystems. By default, the input parameter Look under masks is set to graphical.

  • Allows exclusions of blocks and charts.