% Generate some data
x1 = sort(rand(50, 1));
y1 = randn(size(x1)) + 0.4;
x2 = sort(rand(50, 1));
y2 = randn(size(x2)) + 0.3;
plot(x1, y1, 'r', x2, y2, 'b')
xmin = min([x1; x2]);
xmax = max([x1; x2]);
xq = linspace(xmin, xmax, 1000);
hold on
% Interpolation and max
y1q = interp1(x1, y1, xq, 'linear', 'extrap');
y2q = interp1(x2, y2, xq, 'linear', 'extrap');
plot(xq, max(y1q, y2q), 'k', 'LineWidth', 2);
legend("y1", "y2", "max", "Location", "Best")
