Nrthugu

Im really new in programming with Python and in my final project I need to create this animation where 10 points are randomly moving in space (Brownian motion).

My teacher gave me some examples but I just cant figure out why my program is not working correctly. The error says:

"_included_frames frame_dir=os.path.dirname(frame_list[0]),

IndexError: list index out of range"

Sorry if I didn´t express myself correctly but also English is not my native language.

from math import *

import numpy as np

import matplotlib.pyplot as plt

from mpl_toolkits import mplot3d

import matplotlib.animation as animation



fig = plt.figure()

ax = plt.axes(projection='3d')



N=10

x=500*np.random.random(N)

y=500*np.random.random(N)

z=500*np.random.random(N)



def frame(w):

    ax.clear()





    x=x+np.random.normal(0.0,50.0,10)

    y=y+np.random.normal(0.0,50.0,10)

    z=z+np.random.normal(0.0,50.0,10)



    mensaje="Movimiento Browniano"

    plt.title(mensaje)

    ax.set_xlim3d(-500.0,500.0)

    ax.set_ylim3d(-500.0,500.0)

    ax.set_zlim3d(-500.0,500.0) 



    plot=ax.scatter3D(x, y, z, c='r')





    return plot





anim = animation.FuncAnimation(fig, frame, frames=100, blit=False)



anim.save( 'MovimientoBrowniano.html', fps=5 )

There are two main problems with your code.

1. 
   x,y and z are attempted to be changed locally in your function. However you really want to change the variables defined outside of the function scope. You may easily do that by declaring them globally: Add global x,y,z in your function.


2. 
   

   You are trying to save the animation to an html file. That is no valid video format. I don't know which format you are targeting here, but a common option would be an animated gif, which could be produced by

   
   
   

   anim.save('MovimientoBrowniano.gif', writer = "pillow", fps=5 )