Mathematica bug afflicting our product
Our Mathematica library for wavelet-based time-frequency analysis does not work with the first release of Mathematica 7 due to a bug in Mathematica's FFT routines that silently corrupts data. Any customers using this product are advised to avoid Mathematica version 7.0.0.
Specifically, the Fourier function and all related functions drop the imaginary parts of complex numbers in the result. For example, Mathematica 7.0.0 gives the wrong result here:
In[1]:= Fourier[{0.007 + 0.01 I, -0.002 - 0.0024 I}] Out[1]= {0.00353553, 0.00636396}
The correct answer in this case is:
In[1]:= Fourier[{0.007 + 0.01 I, -0.002 - 0.0024 I}] Out[1]= {0.00353553 + 0.00537401 I, 0.00636396 + 0.00876812 I}
If anyone would be interested in us porting this software to other environments, such as Matlab or F#, please let us know.
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