"""
Exercise 5.11 from "A primer on..."
Modify the previous exercise to set the
axis lengths manually, based on the maximum
values of t and y. This is something
we rarely need to do, but it is necessary 
when making animation and may also be useful 
in other tasks, for instance when comparing 
different plots.
"""


import numpy as np
import matplotlib.pyplot as plt
import sys

g = 9.81

v0_list = sys.argv[1:]

t_max = 0
y_max = 0

for v0 in v0_list:
    v0 = float(v0)
    t_max = 2 * v0 / g
    t = np.linspace(0, t_max, 101)
    y = v0 * t - 0.5 * g * t**2
    plt.plot(t, y)

    #find max values for t and y
    if max(t) > t_max:
        t_max = max(t)
    if max(y) > y_max:
        y_max = max(y)


plt.xlabel('time (s)')
plt.ylabel('height (m)')
plt.axis([0, t_max, 0, y_max*1.05])

plt.show()