jc_0800: Comparing floating-point types in Simulink

Guideline Publication

Control Algorithm Modeling Guidelines - Using MATLAB^®, Simulink^®, and Stateflow^®

• Version 6.0

Sub ID Recommendations

• NA-MAAB — a

• JMAAB — a

MATLAB Versions

All

Rule

Sub ID a

Equivalence comparison operators (==, ~=) shall not be used on floating-point data types.

Custom Parameter

Not Applicable

Example — Correct

Example — Incorrect

Uses equivalence comparison operators == and ~= on the floating-point data type.

Rationale

Sub ID a:

• Due to the characteristics of the floating-point, since the error is included in the value, the result of the equivalence comparison operation may be false when it was expected to be true.

Verification

Model Advisor check: Check comparison of floating point types in Simulink (Simulink Check)

Last Changed

R2020a