Defining upper and lower control limits for a graph

Trying to get thge example below like the one above with set limits for ucl and lcl where ucl = 1.5*mean

Answer 1

[the cyclist]

Here is a simple example of setting plot limits based on the data. (The last line of code is where I set the limits.)

x = 1:50;
y = rand(size(x));

mean_y = mean(y);
ucl =  1.5*mean_y;
lcl = -1.5*mean_y;

figure
plot(x,y)
set(gca,"YLim",[lcl ucl])