#choose suitable values for parameters:
v0 = 5.0
g = 9.81

#choose number of intervals
n = 10

#compute the step length
t_stop = 2*v0/g
dt = t_stop/n

print('First a for loop:')

#i = 0,1,2,...,n
for i in range(n+1):
    #now i = 0,1,2,...,n
    t = i * dt
    #t = 0, dt, 2*dt, ..., n*dt=t_stop
    y = v0 * t - 0.5 * g * t**2
    print('%6.2f %6.2f' %(t,y))


print('Then a while loop:')

"""
Comparing two floats with <= is
unsafe because of roundoff errors.
We add a small number and use <
to avoid this problem.
"""
eps = 1e-10
t = 0
while t < t_stop + eps:
    y = v0*t-0.5*g*t**2
    print('%6.2f %6.2f' %(t,y))
    t += dt

"""
Terminal> python ball_table1.py
First a for loop:
  0.00   0.00
  0.10   0.46
  0.20   0.82
  0.31   1.07
  0.41   1.22
  0.51   1.27
  0.61   1.22
  0.71   1.07
  0.82   0.82
  0.92   0.46
  1.02   0.00
Then a while loop:
  0.00   0.00
  0.10   0.46
  0.20   0.82
  0.31   1.07
  0.41   1.22
  0.51   1.27
  0.61   1.22
  0.71   1.07
  0.82   0.82
  0.92   0.46
  1.02   0.00
"""