Hi all, on the NumPy mailing list (and PR) it came up that CuPy would like to the normalization in FFTs in the opposite way as the defaults. This is for technical reasons on the GPU, but we need to add a new `norm="something"` mode for it. And CuPy, numpy, and scipy should all be happy with the choice. The current favorits are: * "forward" ("backward" could be added to be identical to default) * "reversed" * "inverse" Currently, we scale the *inverse* transformation, instead of the direct transformation. A nice property of the `norm` kwarg is that round- tripping is defined if used always the same: x ~= ifft(fft(x, norm=...), norm=...) (assuming the lengths are good). So that disabling normalization entirely loses the property. If I read it correctly, "forward" is currently the crowd-favorite, and we will probably go ahead with something in a few days. But alternative proposals or opinions on which to choose are very welcome! Cheers, Sebastian