You have to add new values to old ones:
% initialize your data (I do it with empty array to make it easy)
X0 = [];
Y0 = [];
for i=1:3
% update your data with whatever you do, I', just adding i for demonstration purposes
X0 = [X0 i];
Y0 = [Y0 i];
XY1_table = array2table([X0;Y0]','VariableNames',{'X0' 'Y0'})
end
