How to mirror a 3D plot in same coordinates?

clear
clc

m = 100 ; n = 100 ; 

zv = linspace(-1,1,m);
phiv = linspace(0,2*pi,n);
[zv, phiv] = meshgrid(zv,phiv);


rv = ones(size(zv))*1;
% Used the gaussian formula 
%rv2 = -0.8*exp(-1.2*(phiv-4).^2)+1;

% Meshing(Question?)
%[Theta, R] = meshgrid(phiv,rv);

L = linspace(-0,0.5,50);
L=[L fliplr(L)];
zb1 = zeros(m,n,length(L)) ; 

% checking the geometry in Z-direction by value "f"
phiv_loc = phiv(:,1);   % take 1st column
for i = 1:length(L)
    f=L(i);
    rv3(:,i) = -f*exp(-1.2*(phiv_loc-4).^2)+1;
end


%mesh(Theta,R,zv)

% figure(1)
% plot3(phiv,rv,zv)
% hold on
% plot3(phiv,rv2,zv)
% hold on
% plot3(phiv,rv,zb1(:,:,1))
% axis equal

% Converting polar to cartesian cordinates in (x,y,z) direction
[x,y,z]    = pol2cart(phiv,rv,zv);
%[x2,y2,z2] = pol2cart(phiv,rv2,zv);
[x3,y3,z3] = pol2cart(phiv,rv3,zv);

% Coverting Pol2cart inside the loop
%[x3,y3,z3] = pol2cart(phiv,rv,zb1);

figure(2)
%plot3(x,y,z)
%hold on
surf(x3,y3,z3)
%hold on
%plot3(x3,y3,z3(:,1))
axis equal
ax = gca;
%set(gca,'xdir','reverse')
flip(figure(2),2)

Answer 1

[Tejas]

Hello Vilas,

I am assuming that by “mirror of a 3-D plot”, you meant mirror of plot along some axis.

Below is an example of how negating the coordinates of an axis creates a mirror image of plot along that axis. I have created two plots, first plot to show the original plot and second plot to show the mirror of that plot along y-axis.

m = 100; n = 100;
zv = linspace(-1,1,m);
phiv = linspace(0,2*pi,n);
[zv, phiv] = meshgrid(zv,phiv);
rv = ones(size(zv))*1;

L = linspace(-0,0.5,50);
L = [L fliplr(L)];
zb1 = zeros(m,n,length(L));

phiv_loc = phiv(:,1);
rv3 = zeros(size(zv,1), length(L));
for i = 1:length(L)
    f = L(i);
    rv3(:,i) = -f*exp(-1.2*(phiv_loc-4).^2)+1;
end

[x,y,z] = pol2cart(phiv,rv,zv);
[x3,y3,z3] = pol2cart(phiv,rv3,zv);

figure(1)
surf(x3,y3,z3)
axis equal
xlabel('X-axis')
ylabel('Y-axis')
zlabel('Z-axis')
title('Original 3D Plot')

figure(2)
surf(x3,-y3,z3)
axis equal
xlabel('X-axis')
ylabel('Y-axis')
zlabel('Z-axis')
title('Mirrored 3D Plot along y-axis')

Below is Screen Shots of the desired output :

For more information on negation of vector, refer this documentation :

https://www.mathworks.com/help/symbolic/minus.html#bt79p7e-A:~:text=Y%20%3D%0A%5B%20%2D11%2C%20%20%200,0%5D%0A%5B%20%207%2C%2010%5D.

Hope it helps!