Polar Coordinates: filling the areas with RGB color matrix

Hi! I am trying to do a plot like this in Matlab:

There are channels filled with color, in each of the two outter rings there are 32 channels , in the inner rings the number of channels is 8, the total number of channels is 80. Depending on the intensity, the channels are filled with a different color using the RGB scheme. I want to create in Matlab such a plot like the image above, in which Matlab reads the intensity of a specific channel and colors it according to the colormap. My code is the following:

%Make a colormap
    number_of_colors=100;
    colm = jet(number_of_colors);  % choose colorbar (jet)

%Values for indices
    values = transpose(Intensities()); % your data
  values_min = MinWert; % range of the colorbar (defined in another function)
  values_max = MaxWert;    

% Calculate the respective index in the colormap for every value
    idx_in_colorbar = floor(1+ (values - values_min) / (values_max -...
        values_min) * (number_of_colors-1));

% Convert value of index to RGB matrix
    RGB=ind2rgb(idx_in_colorbar, colm);
    RGB= squeeze(RGB)

    figure1=figure(1)
    imshow(imagePATH);
    hold on
    title('Lightintensity of the channels')

%%Lets say we want to create the outter ring here, we have to divide 360° between the 32 channels, and fill from channel 1 to channel 32 the channels, taking the space between r0 and r1 and varying phi (so to say an integral plot filling the area with a color). The color for each channel is taken from the matrix RGB(80x3 matrix). I would use here "patch" but I am not sure how to use it for this case with the polar coordinate plot.

    colormap(colm)
    colorbar
    caxis([handles.MinWert handles.MaxWert]);

This is the array in which the intensities are stored.

Intensities()=

 Columns 1 through 8
       490.82       90.599       920.77       835.62       831.71       15.219       95.392       899.49
  Columns 9 through 16
       728.96       844.82       850.07       745.92          798       827.29       837.52       814.13
  Columns 17 through 24
        880.9       107.99       879.32       938.49       764.72       819.25       799.06       696.44
  Columns 25 through 32
       715.71       108.02       1003.8       975.19       108.35       847.28       127.63       115.78
  Columns 33 through 40
       116.58       785.75       973.51       902.83       949.07       946.87       937.79       823.59
  Columns 41 through 48
       134.26       802.52        974.8       113.26       111.81       888.03       950.62       998.49
  Columns 49 through 56
       949.09       108.25       987.21       702.57       776.54       791.86       920.16       822.43
  Columns 57 through 64
       880.79       932.58          893       842.08       490.42       816.86       866.54       712.23
  Columns 65 through 72
        789.7       730.06       775.99       765.73       676.22       689.65       550.01       846.52
  Columns 73 through 80
       942.06       612.33       92.245       872.52       923.83       88.743       672.14       622.6

Thanks for your help!

Answer 1

[Michael Haderlein]

You can use patches, exactly. Here is an example for the outer ring, I assume that it reaches from r=0.8 to r=1.

 phi=linspace(0,2*pi,33);
 Phi=[phi(1:end-1);phi(1:end-1);phi(2:end);phi(2:end)];
 R=[.8;1;1;.8]*ones(1,32);
 x=R.*cos(Phi);
 y=R.*sin(Phi);
 intensity=ones(4,1)*rand(1,32);
 figure, patch(x,y,intensity), axis equal

I think based on this the remaining rings should be straight-forward.

[Ignacio Lobato]

Thanks Michael for the quick answer! I will try it now :)