goertzel Computes DFT using the second order Goertzel Algorithm Y = goertzel(X,INDVEC,DIM) goertzel(X,INDVEC) Computes the DFT of X at indices INDVEC using the second order algorithm along the first non-singleton dimension. Elements of INDVEC must be positive integers less than the length of the first non-singleton dimension. If INDVEC is empty the DFT is computed at all indices along the first non-singleton dimension goertzel(X,INDVEC,DIM) Implements the algorithm along dimension DIM In general goertzel is slower than fft when computing the DFT for all indices along a particular dimension. However it is computationally more efficient when the DFT at only a subset of indices is desired Example x=rand(1,5) x = 0.6283918 0.8497452 0.6857310 0.8782165 0.0683740 y=goertzel(x,2); y = - 0.3531539 - 0.6299881i Author Ankur Mallick References Goertzel, G. (January 1958), "An Algorithm for the Evaluation of Finite Trigonometric Series", American Mathematical Monthly 65 (1): 34–35, doi:10.2307/2310304