Non-linear Scale for Radius Axis in a Polarhistogram Plot

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Could you please guide me on how to adjust the radius axis (rticks and rticklabels) in the polarhistogram plot below to display a non-linear probability scale? Specifically, I’d like to change the linear scale probability P to a non-linear scale such as 1./abs(log10(P)).
It seems that numberOfMeasurements may not be an option that can be modified into nonlinar to make the connection between number of counts and radius (probabiilty). I am doing this nonlinear scale to amplify the rare exteme current u>80 cm/s. Any advice would be greatly appreciated!
TT1=readtable('Table_data.csv');
%% u as current speed and hdg as current heading
u=TT1.Speed_cm_s_;
hdg=TT1.Heading_degrees_;
figure(1)
pax = polaraxes;
c=colormap("cool");
% Current speed u into 5 groups
u_grp=[20 40 60 80 inf];
num_idx=length(u_grp);
c_idx=round(linspace(1,256,num_idx)); % Color indx for 5 groups
% Current Heading (hdg) into 5 groups
hdg5=deg2rad(hdg(u<=max(u)));
hdg4=deg2rad(hdg(u<u_grp(4)));
hdg3=deg2rad(hdg(u<u_grp(3)));
hdg2=deg2rad(hdg(u<u_grp(2)));
hdg1=deg2rad(hdg(u<u_grp(1)));
hold on
polarhistogram(hdg5,deg2rad(0:10:360),'FaceColor',c(c_idx(5),:),'displayname','>80 m/s')
polarhistogram(hdg4,deg2rad(0:10:360),'FaceColor',c(c_idx(4),:),'displayname','60 - 80 m/s')
polarhistogram(hdg3,deg2rad(0:10:360),'FaceColor',c(c_idx(3),:),'displayname','40 - 60 m/s')
polarhistogram(hdg2,deg2rad(0:10:360),'FaceColor',c(c_idx(2),:),'displayname','20 - 40 m/s')
polarhistogram(hdg1,deg2rad(0:10:360),'FaceColor',c(c_idx(1),:)','displayname',' 0 - 20 m/s')
numberOfMeasurement = size(u,1);
p = [5 10 15]/100; % Probability in percentage %
rticks(p*numberOfMeasurement)
rticklabels(strcat(string(p*100),'%'))
pax.ThetaDir = 'clockwise';
pax.ThetaZeroLocation = 'top';
pax.LineWidth=3;
legend('Show')
title('Current speed {\itu} (cm/s)')
set(gca,'FontSize',12,'FontWeight','bold')
  1 Comment
Hsien-Kuan
Hsien-Kuan on 14 Nov 2024
Moved: Star Strider on 14 Nov 2024
Both the data and output plots are included. If a nonlinear scale for rtick is successfully applied, I can better emphasize rare and extreme events for u>80.

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Accepted Answer

Walter Roberson
Walter Roberson on 14 Nov 2024
polaraxes does not have any way to adjust the scale factor. It does not for example have an RScale property that might (hypothetically) be set to 'log' .
Furthermore, the various axes types that do have *Scale properties only offer to switch between very limited configurations such as 'normal' or 'log' -- nothing as fancy as 1./abs(log10(P))
  1 Comment
Hsien-Kuan
Hsien-Kuan on 14 Nov 2024
Thank you, Walter Roberson. This traditional wind rose chart is very popular, and it would be great to have a nonlinear representation of counts (frequency, or normalized probability) displayed as rtick in a future MATLAB version.

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