Compute N x N DFT matrix

dftmat = DFT matrix of order N x N; N = Order of the matrix computes the DFT matrix of orer N x N; DFT matrix is a n x n matrix defined as Wn=[(Wn)^km] Wn=exp(-j*2*pi/n)Reference: Multirate Systems and Filter banks by P.P Vaidyanathan Pearson...