plot pairwise relationships in matrix : similar to 'pairplot' in seaborn (http://seaborn.pydata.org/generated/seaborn.pairplot.html)
easier than 'plotmatrix'
% e.g.
% For stat toolbox users
load fisheriris.mat
colors = lines(3);
label = {'sepal-length', 'sepal-width', 'petal-length', 'petal-width'}
figure; pairplot(meas, label, species, colors, 'both');
% For all users
load Fisher.mat % included in zip
group= Fisher(:,1);
colors = lines(length(unique(group)));
figure;
pairplot(Fisher(:,2:size(Fisher,2)), {'PW', 'PL', 'SW', 'SL'}, num2cell(num2str(group)), colors, 'bar'), ylabel('Probability')
figure; pairplot(meas, label, species, colors, 'both');