# polar plots axis limits

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Richard Garner on 7 Jun 2011
Commented: rhashaan omar on 9 Sep 2020
How does one set the axis limits in polar plots?

Patrick Kalita on 7 Jun 2011
Well, unfortunately there's no direct way to do it. But you can cheat (yay! cheating!). Let's say you know you want to have the radial dimension go out to 2. You can add a line of constant radius and then make it invisible:
t = 0 : .01 : 2 * pi;
P = polar(t, 2 * ones(size(t)));
set(P, 'Visible', 'off')
Now you can add the data you actually want to plot:
hold on
polar(t, sin(2 * t) .* cos(2 * t), '--r')
Richard Garner on 1 Jan 2017
Thanks for your responses. But I have to take a little exception to your criticism of Matlab. I don't know of any software that is perfect, including Python. I used Python as well as Matlab and find a lot of "issues" with it. My feeling is that alot of people migrate to Python because it's free. Of course, it obviously has ALOT of nice functionality that rivals or even supercedes Matlab. But also that doesn't match up to Matlab. Anyway, just my "2 cents" worth.

Steven Lord on 29 Dec 2016
With the introduction of the polaraxes function in release R2016a you now have access to properties like ThetaLim and RLim.
Richard Garner on 1 Jan 2017
Thanks for that. I did not notice. Guess I hadn't made polar axis plots in awhile.

Mazin Mustafa on 29 Dec 2016
Edited: Mazin Mustafa on 29 Dec 2016
If you want to plot something such as antenna pattern for e.g. -40 dB to 0dB you may use the following code:
data = 10*log10(abs(data)./max(abs(data))); % Normalize your data
range = -40; % Choose the minimum value in dB
data(isnan(data)) = range;
data = data - range;
data = data./max(data);
data(data < 0) = 0;
polar(theta,data,'k')
view([90 270])
set(findall(gcf, 'String', '0' ),'String', ' ');
set(findall(gcf, 'String', ' 0.2' ),'String', num2str(range-(range*0.2)) );
set(findall(gcf, 'String', ' 0.4' ),'String', num2str(range-(range*0.4)) );
set(findall(gcf, 'String', ' 0.6' ),'String', num2str(range-(range*0.6)) );
set(findall(gcf, 'String', ' 0.8' ),'String', num2str(range-(range*0.8)) );
set(findall(gcf, 'String', ' 1' ),'String', '0 dB' );
rhashaan omar on 9 Sep 2020
could you explain? I'm trying to plot a graph of antenna radiation from -30 to 10 dB. I have a table of the values I digitized using an onlne website, but I can't scale my graph to match the original graph.