Many thanks it works !
But so sorry, there's a new error I'm trying to fix from an hour. Because of a header, I've coded as below : delimiterIn=' '; headerLines=11; M=[] ;
for i=1:length(txt)
A=importdata(txt(i).name,delimiterIn,headerLines);
M=[M A];
end
Then I'm trying to view data by writing M.data(1,1) for instance and then I get this message : "Field reference for multiple structure elements that is followed by more reference blocks is an error."
Thank you so much for your help ! Florian