- Input data is an array of complex double-precision
floating-point data, but the FFT core being modeled requires values in single-precision
(32-bit) format. The data must therefore be representable in the MATLAB
software ‘single’ datatype, even if it is represented in the ‘double’ datatype. The value is
explicitly cast to the C++ ‘float’ datatype inside the MEX function.
- Output data has the correct precision to model the FFT.
The double-precision output array contains single-precision values which are representable
in the MATLAB software ‘single’ datatype without error.
-
overflow indicates if exponent overflow
has occurred during the FFT processing. A value of 0 indicates that overflow did not occur;
a value of 1 indicates that exponent overflow did occur.
- If overflow occurred, the output
sample that overflowed is set to ± Infinity, depending on the
sign of the internal result.