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Nielsen is a C FFT by Jens Jorgen Nielsen (1996).

We are not permitted to distribute modified versions of this code (see the license information). If you wish to include this software in the benchmark, you must make some small modifications to the (included) original package, as described below:

Nielsen's original package is in the c_source/mixfft directory. To modify it for use with the benchmark, do the following things:

Once this is done, you have to modify the Makefile so that Nielsen's code will be used. (Or do the equivalent on systems without make.) This requires two changes:
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