for problem you mentioned maybe use writematrix function instead, and use option 'WriteMode' = 'append'.
writematrix(DATAR,filename,'Sheet','Ro','WriteMode','Append');
or you can use writecell exactly the way you use writematrix.
but i'm not sure your doing well at all. the DATAR for example is a cell of all bins returned by imhist. for example a single cell containg an array with size of 256x1. so the part
for D = [DATAR, DATAG, DATAB]
runs 3 times, first time D is DATAR, second time is DATAG and ... .
but you treated D differently.
i think this is what you meant :
%RO
[counts,~] = imhist(Ro);
DATAR = {counts};
%GO
[counts,~] = imhist(Go);
DATAG = {counts};
% Bo
[counts,~] = imhist(Bo);
DATAB = {counts};
writecell(DATAR,filename,'Sheet','Ro','WriteMode','Append');
writecell(DATAG,filename,'Sheet','Ro','WriteMode','Append');
writecell(DATAB,filename,'Sheet','Ro','WriteMode','Append');
with this code you'll have a 25 row with 256 number from hist function in each one.
be carefull using writematrix for your problem, because counts in 256x1 array and each time you append it to xls file the number of row increase by 256 so after 25 image you just have 25x256 row and 1 column. you can transpose the array and then write it to the file for this problem.
