# Finding angles using Matlab atan2 function and plotting the data.

I am learning to use the atan2 function in Matlab. I have a matrix S12 that is 2xdata_size. I am taking the data from the S12 matrix and finding the angle phi12 between points a and b (rows 1 and 2). I am trying to collect the all the phi12 in a matrix and want to histogram plot the information.

This is what I have so far:

 load('S12.mat');
data_size = 10;
Phi12 = zeros(1,data_size);
nbins = 40;
for m = 1:data_size;
a = S12(1,:);
b = S12(2,:);
r12 = sqrt(a.^2 + b.^2);
phi12 = atan2(b/r12,a/r12);
Save_Phi12(:,m) = phi12;
end
h = figure();
Phi12hist = [nbins,Phi12(1,:)];
title('Phi12HIST');
saveas(Phi12HIST,strcat([namefigs,'Phi12HIST']),'fig')


Up to the end of the loop the code works. I am not getting a plot though. And, I need to throw two more loops in that represent S13-->phi13 and S23-->phi23.

Any help, thoughts, suggestions would be greatly appreciated as always! :)
(I'm trying to get this done by tomorrow)

Thanks! Lanae

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