# How to make graph that plot between Analytical Solution (Exact Solution) and Numerical Method Solution?

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Yusuf Arya Yudanto on 5 Mar 2022
Greetings!
Can someone help to guide me how to make graph that plot between Analytical Solution (Exact Solution) and Adams-Moulton Solution? Here I attached my script.
%% 2nd-order Adams-Moulton Solution
fun = @(t,y) ((1+4*t)*((y)^1/2));
y0 = 1;
tspan = [0,1];
N = 4;
%% Initial Values
h = (tspan(2) - tspan(1))/N;
exactY = @(t) (((3*t)/2)+3*t.^2).^(2/3);
t1 = tspan(1) + h; y1 = exactY(t1);
t2 = tspan(1) + 2*h; y2 = exactY(t2);
[t2,Y2] = AM2(fun,tspan,y0,y1,N);
%% Display Solution
Y = exactY(t2);
disp('-----------------------------');
disp('t_i y(t_i) AM2 Error')
disp('-----------------------------');
formatSpec = '%.2f %.5f %.5f %.5f\n';
fprintf(formatSpec,[t2';Y';Y2';abs(Y'-Y2')])
I really appreciate any help you can provide. Thank you.
Yusuf Arya Yudanto on 5 Mar 2022
Many thanks! I really appreciate your help.

Alan Stevens on 5 Mar 2022
After Y = exactY(t2) you probably need something like:
plot(t2,Y2,t2,Y)
legend('AM','Exact')
However, you haven't supplied the code for your AM function, so I can't check!
Yusuf Arya Yudanto on 6 Mar 2022
Hello, Sir Alan. Can you help me make a loglog scale plot of the multiple solutions? I've posted the question, please kindly check it. How to make convergence plot (error VS time step) in a log-log scale among four numerical methods and exact solution?

R2021b

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