How to customise Polar Plots
24 views (last 30 days)
Show older comments
I have data typically graphed as 'value (B) against angle (A)' as a plot (for angles -90 to 90) that I wish to graph as a polar plot. What command(s) can I write that'll graph this data with polar axes for angle as: -90 (on the left) to 90 (on the right) via 0 (below in the middle)?
2 Comments
Star Strider
on 2 Apr 2023
Some detail is missing.
How do you want the tick labels to appear on the left side?
What do you want the top value (currently 180°) to be?
th = linspace(0, 2*pi, 360);
r = sin(2*th).^2;
figure
polarplot(th,r)
Ax = gca;
Ax.ThetaZeroLocation = 'bottom';
TTL = Ax.ThetaTickLabel
.
Accepted Answer
Star Strider
on 4 Apr 2023
Try something like this —
th = linspace(0, 2*pi, 360);
r = exp(-0.1*th).*sin(2*th).^2;
figure
polarplot(th,r)
title('Original')
figure
polarplot(th+pi/2,r) % It May Be Necessary To Shift The Plot Phase (+90° Or +π/2) For This To Work Correctly
Ax = gca;
Ax.ThetaZeroLocation = 'bottom';
Ax.ThetaLim = [270 270+180];
Ax.ThetaTickLabel = compose('%d°',-90:30:90);
title('Shifted')
I needed to make my original function radially asymmetric to test this to be certain it would work correctly. It may be necessary for you to experiment with shifting the angles as well.
.
3 Comments
Star Strider
on 5 Apr 2023
‘One small thing though, how do I set custom gridlines (every 15^o rather than every 30^o)?’
Try this —
th = linspace(0, 2*pi, 360);
r = exp(-0.1*th).*sin(2*th).^2;
figure
polarplot(th,r)
title('Original')
figure
polarplot(th+pi/2,r) % It May Be Necessary To Shift The Plot Phase (+90° Or +π/2) For This To Work Correctly
Ax = gca;
Ax.ThetaZeroLocation = 'bottom';
Ax.ThetaLim = [270 270+180];
Ax.ThetaTick = Ax.ThetaLim(1) : 15 : Ax.ThetaLim(2);
Ax.ThetaTickLabel = compose('%d°',-90:15:90);
title('Shifted With Ticks Every 15°')
.
More Answers (1)
the cyclist
on 2 Apr 2023
Edited: the cyclist
on 2 Apr 2023
% Create plot
figure
theta = linspace(0,2*pi,25);
rho = 2*theta;
polarplot(theta,rho);
% Define a variable with the tick labels
thetaTickLabels = {'0°';'30°';'60°';'90°';'120°';'150°';'180°';'-150°';'-120°';'-90°';'-60°';'-30°'};
% Set theta how you want
set(gca,"ThetaZeroLocation","bottom", ...
"ThetaDir","counterclockwise", ...
"ThetaTickLabels",thetaTickLabels)
Note that while the axes are labeled in degrees, the default input is in radians. (That same page shows how to convert, if you need to.)
See Also
Categories
Find more on 2-D and 3-D Plots in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!