I have trouble with the fftw implemented in MKL. I have written a small code (attached)... Using gnu libfftw3 gives the right answer (mainly the output array is zero but for one coefficient).
However when linking with mkl, I do get a different (and probably false) result where all the array is filled.
Any hint would be welcomed.
Thanks for reaching out to us.
>>I have trouble with the fftw implemented in MKL.when linking with mkl, I do get a different (and probably false) result where all the array is filled.
From the code which you have attached we observed that the kind value is FFTW_R2HC.
As per the documentation, there are some known limitations of FFTW3 wrappers and their usage in Intel oneAPI MKL. The only supported r2r kind values are even/odd DFTs (sine/cosine transforms).
Please refer the following link for details regarding usage of fft wrappers
So we suggest you to try with the supported kind value while implementing with mkl and see if it works.
You can also refer fftw examples which are installed in oneAPI directory under mkl folder.
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