array in matlab

i need to plot 2 arrays together each of which are array <5001x101 double> the plot is the divison of these two graphs. however when putting the values only one appear i need to have the same length array what should i ?? Till now i coded the following code:

for n =1:1:5001
    snr1 = rms(input(n))/ rms(out(n));
end