%add_ex3
data = [8 1.5 0; 5 -1 1; 1 -3 1; 11 2 1; 15 2 -1; 3 -3 0; 10 1 1; 14 1 -1; 2 -3 -1; 9 1.5 1; 6 -1 -1; 12 1.5 1; 4 -1 0; 7 -1 0; 13 1.5 -1;];
plot(data);
title('Starting data');
[y,index] = sort(data(:,1));
for i=1:length(data(:,1))
    out(i,:) = data(index(i),:);
end
figure(2)
plot(out);
title('Data sorted on the first column');
