MATLAB: How do i plot til some x one function and then other

Question

i want to plot plz help

y = { x x<=12

12 x>12 }

Answer 1

x = 0:0.1:20;
y = min(12,x);
plot(x,y,'-+')

In a more general case, use logical indexing, e.g.:

x = 0:0.1:20;
y = x;
y(y>12) = 12;