3 datasets on one skyplot

%Example of the data i have for one sateliite

elevation = [30; 60; 90];

azimuth = [60; 90; 120];

MP = [0.2; 0.7; 0.9];

figure()

skyplot(azimuth, elevation)

% How do i include MP to this skyplot in such a way that colour gradient represents the magintude of MP

[Sarvesh Kale]

can you please tell what is MP ?

[osasunmwen efosa]

MP is multipath. i want to be able to show the multipath for a particular elevation and azimuth angle. Considering the skyplot plot function only allows to plot 2 sets of data ( elevation and azimuth angle), i am unable to include a third one (multipath). Someone suggested that i introduce the multipath dataset as colour but i do not know how. Any suggestions or other options will be helpful.

Answer 1

[Arka]

Hi,

I tried to implement what you wanted using polarplot instead of skyplot.

elevation = [30; 60; 90];
azimuth = [60; 90; 120];
MP = [0.2 0.7 0.9];

cmap = flipud(jet(256)); % color map from blue to red
min_MP = min(MP);
max_MP = max(MP);
c = interp1(linspace(min_MP, max_MP, size(cmap,1)), cmap, MP);

% plot each value pair individually using polarplot
figure;
for i = 1:length(elevation)
    h = polarplot(deg2rad(azimuth(i)), elevation(i), 'o', 'MarkerSize', 10, 'MarkerFaceColor', c(i,:), 'MarkerEdgeColor', 'k');
    hold on;
end
%skyplot(azimuth, elevation, MP, 'o', 'MarkerSize', 10, 'MarkerFaceColor', c, 'MarkerEdgeColor', 'k');
set(gca, 'ThetaZeroLocation', 'top', 'ThetaDir', 'clockwise', 'RTick', [0 30 60 90], 'GridColor', 'k', 'GridAlpha', 0.2);

Here, the closest satellite has the warmest colour. If you want the opposite colour coding, instead of cmap = flipud(jet(256));, do cmap = jet(256);

To learn more about polarplot, please go through the MathWorks documentation link below:

https://www.mathworks.com/help/matlab/ref/polarplot.html

[osasunmwen efosa]

thanks alot. Still some issues. In the original dataset, i have a couple of nans in all three datasets and this make this error ''Invalid RGB triplet. Specify a three-element vector of values between 0 and 1'' pops up when i try to plot. i can not change the nans to zeros because this will end up giving me the wrong results.

[Arka]

You can try removing the corresponding data points containing NaNs from all 3 vectors.

[osasunmwen efosa]

The colours tend to repeat after about four different colurs. The dataset i am trying to convert into colours has a length of 2880 and the variables are in the form of -0.005, 0.001, 0.056 and so on. the image below is what i got from your recommendation

this seems strange as i was expecting to see the range of different colours given on the colormap