Twodimensional DFT

edit

About one dimensional DFT is https://doc.sagemath.org/html/en/refe... But how use twodimensional I try

b = FastFourierTransform(8,8)

but obtain one dimensional array

sage: b [(0.0, 0.0), (0.0, 0.0), (0.0, 0.0), (0.0, 0.0), (0.0, 0.0), (0.0, 0.0), (0.0, 0.0), (0.0, 0.0)]