% Fig4_a
figure;
scatter(X1,Y1,30,'linewidth',2);
hold on
plot(X2,Y2,'linewidth',2)
box on
xlim([17.84,18.09])
ylim([-0.1,0.4])
set (gcf, 'Position', [596,546,270,230]); 
set(gca, 'TickDir', 'out')
