Given that you have the code below, how do you write a code to count the number of points in each quadrant with the attached data set

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Afua Amoako Dadey on 12 Jul 2020
Answered: Walter Roberson on 12 Jul 2020
Classical = pdist2(matrix_logdiff_nsample, mean(matrix_logdiff_nsample),'mahal');
p = size(matrix_logdiff_nsample,2);
chi2quantile = chi2inv(0.99,p);
[SFmcd, MFmcd, Fmcd, OutFmcd] = robustcov(matrix_logdiff_nsample);
plot(Classical, Fmcd, 'o')
line([chi2quantile, chi2quantile], [0, 120], 'color', 'r')
line([0, 80], [chi2quantile, chi2quantile], 'color', 'r')
hold on
plot(Classical(OutFmcd), Fmcd(OutFmcd), 'b*')
xlabel('Mahalanobis Distance')
ylabel('Robust Distance')
title('Distance Plot, Fast MCD method')
Walter Roberson on 12 Jul 2020
For any given point, what are its coordinates based upon the file or variable -- coordinates in the same terms as what is being divided for the purpose of quadrants?
Is the division into quadrants to be based upon half-way through the span of values that appear (mean)? Is it to be based upon median? Is it to be based upon some absolute coordinates (e.g., 0 to 50 and 50 to 100, even if the mean or median might be closer to 70?)
Afua Amoako Dadey on 12 Jul 2020
It is based upon the mean.Thanks

Walter Roberson on 12 Jul 2020
Supposing your two variables are named v1 and v2, then
counts = accumarray([1+(v1(:)>=mean(v1)), 1+(v2(:)>=mean(v2))], 1, [2 2]);