# Display Scale on Quiver Plot

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Jack B on 15 Feb 2015
Commented: kalani Lakshani on 4 Mar 2021
Hello,
I'm looking to display the scale of my arrows on a quiver plot I've produced in relation to the plot itself. So the reader can look at my arrows and understand how they're size relate to the axis of the plot. I hope I'm being clear. Let me know if I'm not.
I basically don't know how to do this. Can anyone offer some suggestions or tips to make this happen.
Jack.

Felipe Breton on 20 Dec 2018
I had the same need, so what I did was to add one extra point in my map with a reference velocity. Then I added some text close to this "reference arrow" to explain it. Of course, some empty space on the map is needed. Basically, it would be as follows:
Taking the example shown in quiver.m 's reference page:
[x,y] = meshgrid(0:0.2:2,0:0.2:2);
u = cos(x).*y;
v = sin(x).*y;
figure
But then:
[X,Y]=meshgrid([0:0.2:2],2.2);
%Then a reference arrow velocity is defined at x=0.2 and y=2.2, while rest of points are left as zero:
u_rf=zeros(1,11);
v_rf=zeros(1,11);
u_rf(1,2)=1;
%Thus, quiver plot is applied including the new row:
quiver([X;x],[Y;y],[u_rf;u],[v_rf;v]); %is done like this to be sure we got the same arrow AutoScale
%Finally some text is included:
text(0.05,2.3,'Arrow scale: 1m/s')
Resulting in the following plot:
I hope it may help someone, as this post it quite old.
Felipe.

Star Strider on 15 Feb 2015
I never thought about doing that with quiver. I’m not certain that what you want to do is possible, but experiment with Quiver Series Properties, specifically those listed under ‘Arrow’.
kalani Lakshani on 4 Mar 2021
Hello @Jack B