Plot three random datasets as circles, dots, and triangles in different colors:

circles, triangles, dots = ax.plot(x, 'ro', y, 'g^', z, 'b.')

This function gets called to update the screen regularly. Update two of the plots with new y values:

def update(data):
    circles.set_ydata(data[0])
    triangles.set_ydata(data[1])
    return circles, triangles

Generate random data with NumPy:

def generate():
    while True: yield np.random.rand(2, N)

The following is a snapshot of the animation in action: