Stateflow User's Guide

Calling C Functions in Actions

This section describes the C functions that you can call directly in Stateflow action language. See the following topics:

• Calling C Library Functions -- Tells you how to call C functions from the math library of your compiler or from custom libraries that you provide.
• Calling min and max Functions -- Describes the special min and max macros that you can call.
• Calling User-Written C Code Functions -- Tells you how to call C functions you provide in custom code for the target you build.

Calling C Library Functions

You can call the following small subset of the C Math Library functions:

abs	acos	asin	atan	atan2	ceil
cos	cosh	exp	fabs	floor	fmod
labs	ldexp	log	log10	pow	rand
sin	sinh	sqrt	tan	tanh

Stateflow extends the abs function beyond that of its standard C counterpart with its own built in functionality. See Calling the abs Function.

You can call the above C Math Library functions without doing anything special as long as you are careful to call them with the right data types. In case of a type mismatch, Stateflow replaces the input argument with a cast of the original argument to the expected type. For example, if you call the sin function with an integer argument, Stateflow replaces the argument with a cast of the original argument to a floating-point number of type double.

If you call other C library functions not specified above, be sure to include the appropriate #include... directive in the Custom code included at the top of generated code field of the Target Options dialog. See the section Specifying Custom Code Options for Stateflow Targets.

Using Special Symbols in Actions

Calling the abs Function

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