x=input('data? ');
y=importdata(x);
t=y.data(:,1);
mx=y.data(:,2);
my=y.data(:,3);
mz=y.data(:,4);
% 
% Fs = length(t)/t(end);
% 
% % average value of time
% mean(t)
% 
% %p=t(t>(0.9*max(t)));