function [parkinson1,parkinson2,test]=parkinson(x,n) if nargin==1 n=25; end dis=length(x)/n; x_max=zeros(n,1); x_min=zeros(n,1); j=1; while j*dis<=length(x) x_max(j)=max(x((round((j-1)*dis)+1):round(j*dis))); x_min(j)=min(x((round((j-1)*dis)+1):round(j*dis))); j=j+1; end l=x_max-x_min; parkinson1=mean(l.*l)/(4*log(2)); parkinson2=mean(l)^2*pi/8; test=2*mean(l.*l)/(log(2)*pi)/(mean(l)^2); end