Does the order of reversing a 2D fft matter?

Question

I have been trying to apply the fft first on the rows and then on the columns resulting from the first application.

My question is, when I try to apply the ifft, do I need to apply it to columns first and then rows, the other way or does it not matter?

Thanks

Answer 1

No, it should not matter. What are you seeing? If you reverse the order (rows and columns) and you get a different answer you probably have a bug. Are you using a library for the FFT or a roll your own approach? And...if you are using a library, do they have a 2D version available?