Matplotlib line chart animation

Question

I am trying to animate a simple line chart with 2 equal arrays. I've seen some guides online but honestly, I'm not sure what I'm doing here, am I close to the solution?

I'm looking for this: https://miro.medium.com/max/1126/1*j0LxVQPbwtQDpL17TH9gZw.gif

import numpy as np
from matplotlib import pyplot as plt
from matplotlib import animation

x = np.array([1,2,3,4,5,6,7,8])
y = np.array([6,9,12,42,50,62,76,82])
fig = plt.figure()
ax = plt.axes(xlim=(1, 8), ylim=(6, 82))
line, = ax.plot([], [], lw=2)

def init():
    line.set_data([], [])
    return line,

def animate(i):
    line.set_ydata(x[i:])
    line.set_xdata(y[i:])
    return line,

anim = animation.FuncAnimation(fig, animate, init_func=init,
                               frames=200, interval=20, blit=True)

anim.save('basic_animation.mp4', fps=30, extra_args=['-vcodec', 'libx264'])
plt.show()

Answer 1

We are changing the way the data is set up. And I changed the number of frames to 9 because the number of data is 8. In addition, I used PIL to create GIF images, so please correct it.

import numpy as np
from matplotlib import pyplot as plt
from matplotlib import animation
from IPython.display import HTML
from matplotlib.animation import PillowWriter

x = np.array([1,2,3,4,5,6,7,8])
y = np.array([6,9,12,42,50,62,76,82])

fig = plt.figure()
ax = plt.axes(xlim=(1, 8), ylim=(6, 82))
line, = ax.plot([], [], lw=2)

def init():
    line.set_data([], [])
    return line,

def animate(i):
    line.set_data(x[:i],y[:i])
    return line,

anim = animation.FuncAnimation(fig, animate, init_func=init,
                               frames=9, interval=200, blit=True)

# anim.save('basic_animation.mp4', fps=30, extra_args=['-vcodec', 'libx264'])
# plt.show()
anim.save('plot_ani.gif', writer='pillow')