% y = sgolayfilt (x, p, n [, m [, ts]]) % Smooth the data in x with a Savitsky-Golay smoothing filter of % polynomial order p and length n, n odd, n > p. By default, p=3 % and n=p+2 or n=p+3 if p is even. % % y = sgolayfilt (x, F) % Smooth the data in x with smoothing filter F computed by sgolay. % % These filters are particularly good at preserving lineshape while % removing high frequency squiggles. Particularly, compare a 5 sample % averager, an order 5 butterworth lowpass filter (cutoff 1/3) and % sgolayfilt(x, 3, 5), the best cubic estimated from 5 points: % % [b, a] = butter(5,1/3); % x=[zeros(1,15), 10*ones(1,10), zeros(1,15)]; % plot(sgolayfilt(x),'r;sgolayfilt;',... % filtfilt(ones(1,5)/5,1,x),'g;5 sample average;',... % filtfilt(b,a,x),'c;order 5 butterworth;',... % x,'+b;original data;'); % % See also: sgolay