Matlab graphs not showing

clear all ;
 
close all;
 
f=@(x,y1,y2) y2;
 
g=@(x,y1,y2) 1/4*y1-8;
 
%shooting method inntialization
 
initialize=[-5:.05:0];

 
%plot the solution
figure
title('shooting method')
xlabel('t')
ylabel('y(t)')
plot(x,y1)
hold on 
 
% make your second plot
figure
(plot(x,1./(4*x-8)'))
 
legend('numerical solution','exact solution')

Answer 1

[Walter Roberson]

You do not have "hold on" in effect, and you are not selecting axes so that the plots are directed to different parts of the figure. Your second plot is replacing the first plot. You should use hold on after the first plot

[N/A]

I added in hold on but it is still not working

[Walter Roberson]

You have an interp1(yy1', initialize', 1/4) . Your yy1 runs from about 2 to 7.2, so 1/4 is outside the defined range. By default when you ask to interp1() at a location that is outside the range of the first parameter, then the result is NaN. That ruins the rest of the calculations. You should add the options 'linear', 'extrap' to the interp1() call in order to enable interpolation.

[N/A]

can you show me?

[Walter Roberson]

p = interp1(yy1', initialize', 1/4, 'linear', 'extrap');