how to add a header to a text file ?

Hello, this my code , I need to add a header to my textfile

for k=1:nbrRect

                        %disp('dans playcallback la nouvelle pos est');
                        Cellule{k}=get(rectangles(k), 'Position');
                        tag=  CellTag(k);
%                        disp('x1 et y1');
                         x1 = Cellule{k}(1)+Cellule{k}(3)/2
                         y1 = Cellule{k}(2)+Cellule{k}(4)/2
                         fprintf(fileID,'%d;%5.3f;%5.3f;%5.3f;%5.3f;%d;%5.3f;%5.3f;\n',tag,Cellule{k}(1),Cellule{k}(2),Cellule{k}(3),Cellule{k}(4),numf,x1,y1);

                    end

fprintf(fileID,'%d;%5.3f;%5.3f;%5.3f;%5.3f;%d;;%5.3f;%5.3f;\n','Person ID','pos1','pos2','Width','height','X centre','Y centre'); I added this line before writing in the file but I didn't find the header in the file

Answer 1

[Stephen23]

One problem is that your fprintf format string contains lots of the numeric format specifier %f, but you are providing inputs which are character vectors! This will not work:

fprintf(fid,'...%f...\n',...,'some char vector',...)
                ^^ %f is for numbers, not char vectors!

Either you will need to use the string specifier %s, something like this:

fprintf(fid,'...%s...\n',...,'some char vector',...)
                ^^ %s is for strings/char vectors!

Or just put all of the names directly into the format string:

fprintf(fid,'Person ID;pos1;pos2;Width;height;X centre;Y centre\n');

How to use the fprintf format strings is explained in the fprintf documentation.