Finding 95 CI of multiple graphs

Hi,

I think i might have confused myself quite a bit with regards to 95%-CI.

I have multiple graphs showing a gradually opening of a fracture. I computed the mean of the graphs by interpolating at the same x-axis.

When i compute the CI-95 do i have to do the same? with interp1?

I have a 19*8 matrix, where the rows correponds to the same x-axis and colums the gradual opening.

This is my code (taking from https://se.mathworks.com/matlabcentral/answers/290707-average-multiple-curves-matlab)

for k1=1:length(theFiles)

xold(:,k1) = M(:,k1);

yold(:,k1)=B(:,k1);

yint(:,k1) = interp1(xold(:,k1), yold(:,k1), xi, 'linear', 'extrap');

end

Then i guess i have to use the yint to compute the confidence interval?

i found this code snippert posted by Star Strider also (https://se.mathworks.com/matlabcentral/answers/159417-how-to-calculate-the-confidence-interval)

x = B; % Create Data

SEM = std(x)/sqrt(length(x)); % Standard Error

ts = tinv([0.025 0.975],length(x)-1); % T-Score

CI = mean(x) + ts*SEM; % Confidence Intervals

Sorry if it may seem like a silly question.

Thanks for the help!