ylim([0 25])
set(gca,'Xtick',[-1:0.5:0.5]);
set(gca,'Ytick',[1 4 8 16]);

set(gca,'Ygrid','off')
set(gca,'Xgrid','on')

for grid_y = [1 2 4 8 16]
pp = [0:0.1:1]; pp(:)=grid_y;
HH=plot([0:0.1:1],pp,'k-'); % 画横线
HH.Color(4)=0.25; % 设置透明度
end