DFT of an audio signal stored as a multi-dimensional array I'm using the Python scipy library to get the data of a particular .wav file into array format. Now, I'd like to find the Discrete Fourier Transform of that signal. The formula for the DFT is,

$X_k = \sum_{n=0}^{N-1}x_{n}e^{-2\pi ink/N}$ for a signal $x(t)$ of length $N$.

The data returned from the wavfile.read function, however, appears as a multi-dimensional array; it begins: array([[0, 0],
       [0, 0],
       [0, 0],
       ...,
       [0, 0],
       [0, 0],
       [0, 0]], dtype=int16). I've seen the formula for the 2D Discrete Fourier Transform, but I was under the impression that this was used for image processing. How would I go about finding the DFT of an audio signal represented by a multi-dimensional array?
It looks like you are reading a stereo file, so you have a left and a right channel. You can do a DFT on the left or a DFT of the right or the mono or all of the above. It really depends on your specific application and requirements.