A floating ball dropped in a water current

While writing the previous script on simple harmonic motion I found a funny simulation.
Here it is, do you remember what happens when you drop a ball in flowing water? (Actually the fluid simulated looks something more dense than water).

	import numpy as np
	import matplotlib.pyplot as plt
	import matplotlib.animation as animation
	import random
	fig = plt.figure()
	ax1 = fig.add_subplot(1,1,1)
	def fun(x):
	if x!=0:
	return 2*np.sin(4/3*x+2)/x
	else:
	return 1
	counter = 1
	def animate(i):
	global x,y,counter
	counter += 0.2
	ax1.clear()
	plt.xlim(0,50)
	plt.ylim(-2,2)
	plt.plot([x for x in range(50)],[-0 for x in range(50)],lw=2,color="cyan")
	plt.plot(counter,fun(counter),color="red",marker="o",ms=20)
	ani = animation.FuncAnimation(fig,animate,interval=1)
	plt.show()

view raw ball_water.py hosted with ❤ by GitHub