如何在Matlab中调整y轴绘图范围？

Question

I need to plot the following functions in matlab

y1=sign(x)
y2=tanh(x)
y3=(x)/(x+1)

The x-range is -5,5 with 0.1 spacing The y-plot range should be between -1.5 to 1.5.

Each plot should have a labeled x and y axis and a legend in the lower right corner.

The only things I cant figure out is how to adjust the y plot range. Ive tried editing the actual figure but all that seems to do is distort the graph. Is there a command within matlab that will let me adjust the y axis plot range?

The other thing I havent figured out yet is adding a legend, I can do it after the figure is created but I guess it needs to be done by matlab command.

Answer 1

是的，在plot命令后使用axis ：

axis([-5 5 -1.5 1.5])

Answer 2

If you only want to set the y-range without setting the x-range you can use

ylim([-1.5 1.5])

or alternatively axis([-inf inf -1.5 1.5]) . I found this from the original MATLAB-source: https://de.mathworks.com/help/matlab/ref/ylim.html

PS: For trigonometric functions I would recommend to use axis equal to have equally spaced x and y-axis (see MATLAB )