Superimposing two 3 D surface plots

I have multiple surface plots written using surf or mesh command. I now want to plot two or more surface plots in the same figure in order to show the difference between the two. For 2-D plots, its very straightforward. But I am unable to do so for 3D plots. Kindly help. I have given a sample code where u or U represents the two outputs to be plotted on the z- axis and x1 and x2 are the two input variables to be plotted on the x and y axes.Although u and U are different, the difference is not visible on the plot.

clc
clear all
close all
%tic
range=1;
resolution=0.1;
x1=-range:resolution:range;
x2=-range:resolution:range;
k=(range/resolution)*2+1;
h=1;
h1=1;
H=2;
H1=2;
A=1;
B=2;
for i=1:k;
    for j=1:k;
       
            
      if (x1(i)>=-h) && (x1(i)<=h) && (x2(j)>=-h1) && (x2(j)<=h1)
           u(i,j)=-((2*A^2+5*A*B+2*B^2)*(x2(j)*h+x1(i)*h1))/(3*(A+B)*(x1(i)*x2(j)-3*h*h1));        
 
       else
           u(i,j)=0;
    end
end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
for q=1:k
    for j=1:k
      
       if (x1(q)>=-h) && (x1(q)<=h) && (x2(j)>=-h1) && (x2(j)<=h1)&& x2(j)<=(h1/h)*x1(q) 
            U(q,j)=-((x2(j)*h + x1(q)*h1)*((A - B)^2*x2(j)^2*(3*x1(q)^2 + h^2) -8*(A - B)*(2*A + B)*x2(j)*x1(q)*h*h1+((A - B)^2*x1(q)^2 - 3*(A + 3*B)*(7*A + 5*B)*h^2)*h1^2))/(24*h*h1*((A - B)*x2(j)^2*(x1(q)^2 + x1(q)*h + h^2)-x2(j)*((A - B)*x1(q)^2 + (A + 3*B)*h^2)*h1 +((A - B)*x1(q)^2 + (A + 3*B)*x1(q)*h + (A + 7*B)*h^2)*h1^2));
            
       
       elseif (x1(q)>=-h) && (x1(q)<=h) && (x2(j)>=-h1) && (x2(j)<=h1)&& x2(j)>=(h1/h)*x1(q)  
           U(q,j)=-((x2(j)* h + x1(q)*h1)*((A - B)^2*x2(j)^2*(3*x1(q)^2 + h^2)-8*(A - B)*(2*A + B)*x2(j)*x1(q)*h*h1+((A - B)^2*x1(q)^2 - 3*(A + 3*B)*(7*A + 5*B)*h^2)*h1^2))/(24*h*h1*((A - B)*x2(j)^2*(x1(q)^2 - x1(q)*h + h^2)+x2(j)*((A - B)*x1(q)^2 + (A + 3*B)*h^2)*h1+((A - B)*x1(q)^2 - (A + 3*B)*x1(q)*h + (A + 7*B)*h^2)*h1^2));
       
         
       
       else
           U(q,j)=0;
    end
end
end

% sUrf(x1,x2,U')
%mesh(x1,x2,U') 
%Y14=u'-U';
mesh(x1,x2,u')
hold on
mesh(x1,x2,U')
xlabel('x1'), ylabel('x2'),zlabel('u or U')

[KSSV]

How about

surf(x1,x2,u'-U')

[SM]

Thank you @KSSV, this one I have tried. However I wanted to know is there any other way to do it just like we do for 2D plots.

Answer 1

[Chaitanya]

Hello SM

I see that you are trying to superimpose 2 mesh plots.

The approach of setting ‘hold on’ is the correct way to super impose the 3D plots. However, in your case, both the plots are similar. Hence it seems as a 1 plot.

I was able to set different colors (red and blue) for the plot and was able to identify that the 2 plots.

Please refer to the code that I used and the corresponding output.

mesh(x1,x2,u','EdgeColor', 'r')
hold on
mesh(x1,x2,U','EdgeColor', 'b', 'FaceAlpha', 0.5)
xlabel('x1'), ylabel('x2'),zlabel('u or U')

Also refer to the following link for more information on mesh plots and setting different colors for the same.

https://in.mathworks.com/help/matlab/ref/mesh.html?searchHighlight=mesh%20plot%20color&s_tid=srchtitle_support_results_1_mesh%20plot%20color#namevaluepairs

Thanks,

Chaitanya