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Subsystem method arguments


Customize generated function argument names for reusable subsystems.

Category: Code Generation > Identifiers


Enter a macro that specifies whether, and in what order, certain text is to be included in the generated argument name. The macro can include a combination of the following format tokens.

  • Insert u if the argument is an input.

  • Insert y if the argument is an output.

  • Insert uy if the argument is an input and output.



Insert name-mangling text if required to avoid naming collisions.



Insert name of object (block, signal or signal object, state, parameter or parameter object) for which identifier is being generated.

Recommended to maximize readability of generated code.


Insert text that you specify for the $U token. Use the Custom token text parameter to specify this text.


  • Avoid name collisions in general. One way is to avoid using default block names (for example, Gain1, Gain2...) when your model has many blocks of the same type.

  • Where possible, increase the Maximum identifier length to accommodate the length of the identifiers you expect to generate. Reserve at least three characters for name-mangling text.

  • To control the case (upper or lower case) of the text that each token represents, include decorators such as [U_] in your macro. See Control Case by Using Token Decorators.


This parameter:

  • Appears only for ERT-based targets.

  • Requires Embedded Coder® when generating code.

Command-Line Information

Parameter: CustomSymbolStrFcnArg
Type: character vector
Value: valid combination of tokens
Default: rt$I$N$M

Recommended Settings

DebuggingNo impact
TraceabilityUse default
EfficiencyNo impact
Safety precautionNo recommendation

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