The subs command can be combined with double to evaluate a symbolic expression numerically. Suppose you have the following expressions
syms t M = (1 - t^2)*exp(-1/2*t^2); P = (1 - t^2)*sech(t);
and want to see how M and P differ graphically.
One approach is to type the following commands, but the resulting plot does not readily help you identify the curves.
ezplot(M) hold on ezplot(P) hold off
Instead, combine subs, double, and plot to produce a multicolored graph that indicates the difference between M and P.
T = -6:0.05:6; MT = double(subs(M, t, T)); PT = double(subs(P, t, T)); plot(T, MT, 'b', T, PT, 'r-.') title(' ') legend('M','P') xlabel('t') grid