%% Optimize FFT with Padding
% Use the nextpow2 function to increase the performance of fft when the length of a signal is not a power of 2.
% Create a 1-D vector containing 8191 sample values.

x = gallery('uniformdata',[1,8191],0);

%
% Calculate the next power of 2 higher than 8191.

p = nextpow2(8191);
n = 2^p

%
% Pass the signal and the next power of 2 to the fft function.

y = fft(x,n);

% Copyright 2012 The MathWorks, Inc.