there is an article said that the phase spectrum is π or 0. I don't know it's right or not. so i used fft function to check it. the result is not same as the article.the matlab code is below, is there something wrong?thank you very much.
S=[zeros(1,25) ones(1,50) zeros(1,25)];
Y = fft(S,N);
Ayy = (abs(Y));
title('magnitude spectra ');
title(' phase spectrum');