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Custom FFT library callback

Callback for custom FFT library usage

Model Configuration Pane: Code Generation


The Custom FFT library callback parameter specifies a callback class for FFTW library calls in the code generated for FFT functions in MATLAB® code. This parameter applies to MATLAB code in a MATLAB Function block, a Stateflow® chart, or a System object™ associated with a MATLAB System block.

To improve the execution speed of FFT functions, the code generator produces calls to the FFTW library. You can either use the code generator's built-in callback or define the custom callback class for FFTW library calls.


'' (default)

Specifies the name of an FFT library callback class. If this parameter is empty, the code generator uses its own algorithms for FFT functions instead of calling the FFTW library.


Specify only the name of the class. Do not specify the name of the class definition file.

Recommended Settings

DebuggingNo impact
TraceabilityNo impact
EfficiencyNo impact
Safety precautionNo impact

Programmatic Use

Parameter: CustomFFTCallback
Type: character vector
Value: class name
Default: ''


The class definition file must be in a folder on the MATLAB search path.

Version History

Introduced in R2017b