Hi there, I am a complete novice at using matlab and am trying to work out if there is a way of optimising my code. Essentially I have data from model outputs and I need to plot them using matlab. In addition I have reference data (with 95% confidence intervals) which I plot on the same graph to get a visual idea on how close the model outputs and reference data is. In terms of the model outputs I have several thousand files (number sequentially) which I open in a loop and plot. The problem/question I have is whether I can preprocess the data and then plot later - to save time. The issue I seem to be having when I try this is that I have a legend which either does not appear or is inaccurate. My code (apolgies if it not elegant): fn= xlsread(['tbobserved' '.xls']); time= fn(:,1); totalreference=fn(:,4); totalreferencelowerci=fn(:,6); totalreferenceupperci=fn(:,7); figure plot(time,totalrefrence,'-', time, totalreferencelowerci,'--', time, totalreferenceupperci,'--'); xlabel('Year'); ylabel('Reference incidence per 100,000 population'); title ('Total'); clickableLegend('Observed reference data', 'Totalreferencelowerci', 'Totalreferenceupperci','Location','BestOutside'); xlim([1910 1970]); hold on start_sim=10000; end_sim=10005; h = zeros (1,1000); for i=start_sim:end_sim %is there any way of doing this earlier to save time? a=int2str(i); incidenceFile =strcat('result_', 'Sim', '_', a, 'I_byCal_total.xls'); est_tot=importdata(incidenceFile, '\t', 1); cal_tot=est_tot.data; magnitude=1; t1=cal_tot(:,1)+1750; totalmodel=cal_tot(:,3)+cal_tot(:,5); h(a)=plot(t1,totalmodel); xlim([1910 1970]); ylim([0 500]); hold all clickableLegend(h(a),a,'Location','BestOutside') end Essentially I was hoping to have a way of reading in the data and then plot later - ie. optimise the code. I hope you might be able to help. Thanks. mp