How to create a 2D circular intensity plot?

Hi, I can generate 2D plots like in the image above in comsol. I want to generate the same in matlab. This is a plot of electric field distribution in a cylindrical resonator. My matlab code has the electric field as a function of radius and angle. May be creating a meshgrid and then using polar command might be the way to go but I am not sure how to do that correctly. Any suggestion or link would be appreciated. Thanks </matlabcentral/answers/uploaded_files/22752/snapshot.png>

Answer 1

[Thorsten]

Define your X Y Cartesian coordinates with meshgrid, convert to radius and angle

 R = sqrt(X^2 + Y^2);
 A = atan2(Y, X);

and run your function on R and A.

Answer 2

[Zeba]

Thanks for your reply! I am sorry, I meant Electric field values are calculated and stored in a matrix. So I know what's the field at a given radius and angle. I used the following snippet to make it work axes(handles.axes2)

[rr, tt]=meshgrid(linspace(0,2*r(1),length(y)), linspace(0,2*pi,length(y)));

xx=rr.*cos(tt);

yy=rr.*sin(tt);

hh=polar(xx,yy);

zz=(repmat(y,length(y),1).*cos(m*tt)).^2;

hold on; pcolor(xx,yy,zz); shading interp; set(hh,'visible', 'off');

axis off

axis image I had found part of it on some webpage while searching for help. When I try to change the colorbar range, I get an error Error using set

Bad property value found.

Object Name: axes

Property Name: 'CLim'

Values must be increasing and non-NaN.

The code for the up and down pushbuttons in the figure below is

% --- Executes on button press in pushbutton11.

function pushbutton11_Callback(hObject, eventdata, handles)

color_range=get(handles.axes2,'Clim');

newcolor_range=[color_range(1)*2 0];

set(handles.axes2,'Clim',newcolor_range)

% --- Executes on button press in pushbutton12.

function pushbutton12_Callback(hObject, eventdata, handles)

color_range=get(handles.axes2,'Clim');

newcolor_range=[color_range(1)/2 0];

set(handles.axes2,'Clim',newcolor_range)

How do I get rid of this error while changing colorbar range? It works with normal axes. Thanks

[Thorsten]

This is a new question. Please accept my answer and start a new question with a new title that better reflects your current problem.

[Zeba]

I figured out the problem. Thanks

[Thorsten]

Please formally accept my answer if it was helpful.

[MatlabUser]

can you please share the working code with intensity input thing?