An error in filtfilt

Question

Neda Deljavan 2022-10-1

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1815510-an-error-in-filtfilt

编辑： Bruno Luong 2022-10-1

load P01EC1
sig= P01EC1(:,:)';

sig is 4x30800 double

When I did like this:

subs_cd1_alpha=filtfilt(b,a,sig);
I’ve got this error:
Error using filtfilt>getCoeffsAndInitialConditions (line 228)
Data length must be larger than 18 samples.
Error in filtfilt>efiltfilt (line 129)
[b2,a2,zi,nfact,L] = getCoeffsAndInitialConditions(b,a,Npts);
Error in filtfilt (line 89)
y=efiltfilt(b,a,x);
Error in subject_01_EC1Ac (line 287)
subs_cd1_alpha=filtfilt(b,a,sig);

And

In this case:

for i=1:4
    subs_cd1_alpha=filtfilt(b,a,sig(:,i));
end
This error happened:
Error using filtfilt>getCoeffsAndInitialConditions (line 228)
Data length must be larger than 18 samples.
Error in filtfilt>efiltfilt (line 129)
[b2,a2,zi,nfact,L] = getCoeffsAndInitialConditions(b,a,Npts);
Error in filtfilt (line 89)
y=efiltfilt(b,a,x);
Error in subject_01_EC1Ac (line 285)
subs_cd1_alpha=filtfilt(b,a,sig(:,i));