matplotlib example animate distances (snippet)

Python matplotlib example 'animate distances'

Functions in program:

def animate(i):
def initialize_animation():

Modules used in program:

import matplotlib
import numpy as np

python animate distances

Python matplotlib example: animate distances

import numpy as np
import matplotlib
matplotlib.use('TKAgg')
from matplotlib import pyplot as plt
from matplotlib import animation

from .data import WALLS, TRAJECTORIES


# First set up the figure, the axis, and the plot element we want to animate
figure = plt.figure(figsize=(18, 6))
axis = plt.axes(xlim=(-4.2, 4.2), ylim=(-4.2, 4.2))
axis.set_aspect('equal', 'box')

trajectory_lines = [
    axis.plot([], [], lw=2, marker='o', markersize=5)[0]
    for trajectory in TRAJECTORIES
]

# line = axis.plot([], [], lw=2)[0]

wall_lines = [
    axis.plot(*zip(*wall), lw=8, color='black')[0]
    for wall in WALLS
]


# initialization function: plot the background of each frame
def initialize_animation():
    return (*trajectory_lines, *wall_lines)


# animation function.  This is called sequentially
def animate(i):
    step_budget = i

    for j, (trajectory, trajectory_line) in enumerate(zip(
            TRAJECTORIES, trajectory_lines)):
        visible_data = trajectory[:min(step_budget, len(trajectory))]
        x, y = (zip(*visible_data)
                if visible_data
                else ((), ()))
        trajectory_line.set_data(x, y)
        step_budget -= len(visible_data)

    return (*trajectory_lines, *wall_lines)

# call the animator.  blit=True means only re-draw the parts that have changed.
anim = animation.FuncAnimation(
    figure,
    animate,
    init_func=initialize_animation,
    frames=sum(map(len, TRAJECTORIES)) + 6,
    interval=1000,
    blit=False)

plt.axis('off')
figure.tight_layout()
# anim.save('basic_animation.mp4', fps=30, extra_args=['-vcodec', 'libx264'])
anim.save('animation.gif', fps=10, writer='imagemagick')

# plt.show()

Python links

Learn Python: https://pythonbasics.org/
Python Tutorial: https://pythonprogramminglanguage.com