Plot not as expected

Could someone help me with this t=1:1:200

v1=1+3*t

v2=1-0.2*t

vs=v1

vs(v1>60)=v2(v1>60)

plot(t,vs)

I was trying to plot the velocity of an object.It accelerate at 3 m/s2 until 60, and then slows down at 0.2.

The plot consists of dispersed parts from the two functions, instead of a zigzag fluctuation around 60 which is what I am trying to achieve. I understand why the plot is like this, but failed to come up with a solution.

[James Tursa]

Is the "greater-than-60" criteria assumed to only be checked on the 1 sec boundaries? The resulting velocity is going to depend on exactly when you make this check. You may need to put this in a for loop and step-by-step apply the +3.0 or the -0.2 depending on the current value of velocity.