Multi dimension fft

[ghost]

First of all great effort to port a amazing fft library to an amazing programming language. I am relatively new to rust and come from a more c++ heavy background. I am struggling a bit in understanding how to use the multi dimensional fft. I saw that there are some commits related to this feature. When trying to figure out how to actually create the plan for this and pass the data I fail though. Would be amazing if someone could point me into the right direction. Best wishes, Malte