Greetings dear friends, I am trying to change some variables in the indicated code to get the waves that can be seen in the 3D graph, thanks for your help!

By this means the experts helped me with this code for which I am grateful and I have tried to obtain the waves indicated in the final 3D graph that I wish to create:

In the results I see this graph (Which cordially helped me by this means):

The code is this:

Thank you so much!

Answer 1

[Simon Chan]

Better to check the limits to generate your sample figure. Looks like from -3pi to 3pi as shown below:

As the limits goes to infinity, it smears out the oscillation and becomes a straight line. So your code is correct.

clear; clc;
t = linspace(0.001,2,50);
x = linspace(-2,2,50);
[T,X] = meshgrid(t,x);
tiledlayout(3,3,'TileSpacing','compact','Padding','compact');
for k = 1:9
    for r = 1:numel(x)
        for s = 1:numel(t)
            f = @(p) (1/(pi*sqrt(2*pi))).*(sin(p)./p).*exp(-(T(r,s)*p.^2)+i*(p*X(r,s)));
            F(r,s) = integral(f,-k*pi,k*pi);
        end
    end
    nexttile
    surf(T,X,real(F));
    colormap(flip(autumn()));
    xlabel('t');
    ylabel('x');
    zlabel('u(x,t)');
    title(sprintf('Limits: -%d%s to %d%s',k,'\pi',k,'\pi'));
end

 for r = 1:numel(x)
        for s = 1:numel(t)
            f = @(p) (1/(pi*sqrt(2*pi))).*(sin(p)./p).*exp(-(T(r,s)*p.^2)+i*(p*X(r,s)));
            F(r,s) = integral(f,-3*pi,3*pi);
        end
 end
figure(2)
surf(T,X,real(F));
colormap(flip(autumn()));
xlabel('t');
ylabel('x');
zlabel('u(x,t)');

[Lewis HC]

Thank you dear Simon, I am trying to run this code but o can´t to get a correct graph, I would appreciate it if you correct me:

t = linspace(0.001,2,50);
x = linspace(-2,2,50);
[T,X] = meshgrid(t,x);
for r = 1:numel(x);
    for s = 1:numel(t);
        f = @(p)(1/(pi*sqrt(2*pi))).*(sin(p)./p).*exp(-(T(r,s)*p.^2)+i*(p*X(r,s)));
        F(r,s) = integral(f,-3*pi,3*pi);
    end
end
surf(T,X,real(F));
colormap(flip(autumn()));
xlabel('t');
ylabel('x');
zlabel('u(x,t)');

I get this:

One again, thank you for your help dear friend!

[Simon Chan]

Try to clear the workspace or restart MATLAB before running the code.

clear; clc;                         % <--- Clear the workspace
t = linspace(0.001,2,50);
x = linspace(-2,2,50);
[T,X] = meshgrid(t,x);
for r = 1:numel(x);
    for s = 1:numel(t);
        f = @(p)(1/(pi*sqrt(2*pi))).*(sin(p)./p).*exp(-(T(r,s)*p.^2)+i*(p*X(r,s)));
        F(r,s) = integral(f,-3*pi,3*pi);
    end
end
surf(T,X,real(F));
colormap(flip(autumn()));
xlabel('t');
ylabel('x');
zlabel('u(x,t)');

[Lewis HC]

I have to tell you that you are one of the best dear friend, thank you very much, you helped me as you can not imagine, greetings!