t = 0:pi/20:2*pi;
[x,y] = meshgrid(t);
subplot(2,2,1)
z = sin(x)+cos(y);
plot(t,z)
grid on
%打開網格線
subplot(2,2,2)
plot(t,z)
axis([0 2*pi -2 2])
hold on
%在當前圖形上繪制數據
plot(t,sin(x).*cos(y)) 
hold off
%關閉
subplot(2,2,3)
plot(t,z)
axis ij
%矩陣式坐標，原點在左上方
axis off 
%關閉坐標軸
subplot(2,2,4)
plot(t,z)
set(gca,'Xtick',0:.5:6,'Ytick',-2.5:0.5:2.5)
%設定坐標軸的刻度