How to draw a sidebar in polar plotting?

How can I draw a sidebar (red encircled) with a polar plot as shown in figure.

My program and figure are given below:

clc;
clear all;
close all;
%% ------------------------------Program-------------------------------------
N0=100;
r_med=[0.445 0.889 1.445 8];
sigma_g=7;
N_ang=91;
theta =0:(pi/180): (2*pi);
Num_r = 50e3;
r = linspace(1,50,Num_r)./2;
col=['k' 'b' 'r' 'g'];
for i=1:length(r_med)
[s1(i,:),s2(i,:),~,~,~,~]=bhmie(r_med(i),1.33,91)
cs1(i,:)=conj(s1(i,:));
cs2(i,:)=conj(s2(i,:));
ph_ft(i,:)=s1(i,:).*cs1(i,:)+s2(i,:).*cs2(i,:);
Rs1(i,:)=real(s1(i,:));
Rs2(i,:)=real(s2(i,:));
phf(i,:)=[ph_ft(i,:) fliplr(ph_ft(i,2:181))];
polarplot(theta,phf(i,:));
end
%% -------------------------------Title--------------------------------------
figure('name','Polar plot of scattering phase')
subplot(2,2,1,polaraxes);
hold on
polarplot(theta,phf(1,:),'color',col(1),'Linewidth',1.5);
title('\bf (a) Scattering phase function','FontSize',...
    16,'FontWeight','normal')%\bf(bold font),\rm(normal font),\it(italian font)
legend('R_{e}=4\mum','location','south','FontSize',12);
legend boxoff
set(gca,'color','w','Fontsize',12,'LineWidth',1,'Fontweight','normal');
set(gca,'box','on','Fontname','Arial','Fontsmoothing','on');
%%
subplot(2,2,2,polaraxes);
hold on
polarplot(theta,phf(2,:),'color',col(2),'Linewidth',1.5);
title('\bf (b) Scattering phase function','FontSize',...
    16,'FontWeight','normal')%\bf(bold font),\rm(normal font),\it(italian font)
legend('R_{e}=8\mum','location','south','FontSize',12);
legend boxoff
set(gca,'color','w','Fontsize',12,'LineWidth',1,'Fontweight','normal');
set(gca,'box','on','Fontname','Arial','Fontsmoothing','on');
%%
subplot(2,2,3,polaraxes);
hold on
polarplot(theta,phf(3,:),'color',col(3),'Linewidth',1.5);
title('\bf (c) Scattering phase function','FontSize',...
    16,'FontWeight','normal')%\bf(bold font),\rm(normal font),\it(italian font)
legend('R_{e}=13\mum','location','south','FontSize',12);
legend boxoff
set(gca,'color','w','Fontsize',12,'LineWidth',1,'Fontweight','normal');
set(gca,'box','on','Fontname','Arial','Fontsmoothing','on');
%%
subplot(2,2,4,polaraxes);
hold on
polarplot(theta,phf(4,:),'color',col(4),'Linewidth',1.5);
title('\bf (d) Scattering phase function','FontSize',...
    16,'FontWeight','normal')%\bf(bold font),\rm(normal font),\it(italian font)
legend('R_{e}=72\mum','location','south','FontSize',12);
legend boxoff
set(gca,'color','w','Fontsize',12,'LineWidth',1,'Fontweight','normal');
set(gca,'box','on','Fontname','Arial','Fontsmoothing','on');

% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[.3 .05 .45 .75])
print(gcf,'Polar plot of scattering phase.tiff','-dtiff','-r300'); 

[Star Strider]

What does the sidebar represent, what are the units, and does it have a specific relation to the polar plot?

[Wiqas Ahmad]

the polar plot reprsents the distribution of light while the vertical bar represents the scattering intesity in units of steradian

Answer 1

[Chunru]

theta =0:(pi/180): (2*pi);
r = cos(theta)

r = 1×361

1.0000 0.9998 0.9994 0.9986 0.9976 0.9962 0.9945 0.9925 0.9903 0.9877 0.9848 0.9816 0.9781 0.9744 0.9703 0.9659 0.9613 0.9563 0.9511 0.9455 0.9397 0.9336 0.9272 0.9205 0.9135 0.9063 0.8988 0.8910 0.8829 0.8746

ax=subplot(221);
polar(theta, r);
pos = ax.Position

pos = 1×4

0.1300 0.5838 0.3347 0.3412

pos(1) = pos(1)-0.05;   % adjust pos to fit your need
ax1 = axes('Position', pos, 'Color', 'none'); 
ax1.XAxis.Visible = 'off';  % turn off x axis
ax1.YLim = [-2 2];
ax1.YLabel.String = "Phase Function sr^1";
ax1.YMinorTick = 'on';
ax1.TickDir = 'out';

[Wiqas Ahmad]

Thank you so much.