## Discrete Fourier Transform

Hi,
the discrete fourier transform theory provides that the index in the sum that reconstructs the original n points (the antitransform) goes from 0 to N-1 (N is the period).
Indeed the Fourier complex series goes from negative to positive index (virtually from -inf to +inf). Why? Why some authors instead use: from -N/2 to N/2-1?

thank you