Mirror of countourf on X, Y axis

Hello everyone,

I'm working on 2d unsteady heat transfer modeling using Fortran. i have my results (temperature field) but only on 1/4 of my rectangel because i have (symetrical Boundary conditions).

I drew the results using matlab (countourf (x,y,z...), z=temperature, on 1/4 of the rectangle. can anyone of you explain me how to draw the temperature field on the entire rectangle ?? because it's symetrical, i would like to use mirror effect on x y axis. (-x-y) (-x+y) (x-y)

i don't wanna to multiply dimension of each vector *4, i tried it, it worked but very very slow.

there is my code : close all; clear;clc; a=load('new4.txt'); N=100

x=a(:,1); x coord y=a(:,2); y coord z=a(:,3);% temperature vetor

methode='v4'; Xmin = min(x); Xmax = max(x); Ymin = min(y); Ymax = max(y);

X =linspace(Xmin,Xmax,N); Y =linspace(Ymax,Ymin,N);

[X,Y] = meshgrid(X,Y);

Z = griddata(x,y,z,X,Y, methode); [c]=contourf(+X,+Y,Z,10); .

Thank you in advance.

Answer 1

[Sara]

Look at the following example. If x and y start from 0, you can repeat the contour command 4 times. otherwise, you need to translate your coords.

x = 0:0.1:10;
y = -0:0.1:10;
[x,y]= meshgrid(x,y);
z = x.^2+y.^2;

figure
hold on
contourf(x,y,z)
contourf(-x,y,z)
contourf(x,-y,z)
contourf(-x,-y,z)

xlim([-10 10])
ylim([-10 10])

[ayoub]

Thank you,

I did it finally figure

hold on %X =linspace(Xmin,Xmax,N); %Y =linspace(Ymax,Ymin,N);

[X,Y] = meshgrid(X,Y);

Z = griddata(x,y,z,X,Y, methode);

[c]=contourf(+X,-Y,Z,10); [c]=contourf(+X,-Y,Z,10); [c]=contourf(-X,-Y,Z,10); [c]=contourf(-X,+Y,Z,10); [c]=contourf(+X,+Y,Z,10);

axis equal tight

but the grid is gone :(. why?

[Sara]

Add this at the end

set(gca,'layer','top');
grid on