Numerically determining the highest a ball travels when shot straight up

[JakeWitten]

Hi all, I'm very new to python and I have no prior experience with other coding languages, so my main issues are with the formatting and finding the appropriate vocabulary. 

My goal is to determine the maximum height a ball reaches when thrown straight up.  I already wrote the code for the visual of the ball, but I don't know how to find and display a maximum value.  Any other advice or suggestions in regards to the code I already have would also be greatly appreciated.

Thanks! 

from visual import *

myuniv = display(range = vector(3,3,3))

So = vector(0,1,0)
Vo = vector(0,6,0)
a = vector(0,-9.8,0)
s = vector(0,2,0)

dt = 0.1
t = 0.0

ball = sphere(pos = s, radius = 0.25, color = color.cyan)

while s.y > -2.0:
    rate(25)
    s = .5*a*t**2 + Vo*t + So
    v = a*t + Vo
    t = t + dt
    ball.pos = s
    ballghost = sphere(pos = s, radius = .2)