I am getting an error while running fftw2d on a 1-column matrix:
fftw2d(matrix(c(1, 2, 3, 9, 8, 5, 1, 2, 9, 8, 7, 2), ncol=1))
Error in res[idxRowAppend, nC:2] : subscript out of bounds
There is no problem with a "transposed" (horizontal) call:
fftw2d(matrix(c(1, 2, 3, 9, 8, 5, 1, 2, 9, 8, 7, 2), nrow=1))