matplotlib绘制动画

　　matplotlib从1.1.0版本以后就开始支持绘制动画，具体使用可以参考官方帮助文档。下面是一个很基本的例子：

"""
A simple example of an animated plot
"""
import numpy as np
from matplotlib import pyplot as plt
from matplotlib import animation

# First set up the figure, the axis, and the plot element we want to animate
fig = plt.figure()
# create our line object which will be modified in the animation
ax = plt.axes(xlim=(0, 2), ylim=(-2, 2))
# we simply plot an empty line: we’ll add data to the line later
line, = ax.plot([], [], lw=2) 


# initialization function: plot the background of each frame
def init():
    line.set_data([], [])
    return line,

    
# animation function.  This is called sequentially
# It takes a single parameter, the frame number i 
def animate(i):
    x = np.linspace(0, 2, 1000)
    y = np.sin(2 * np.pi * (x - 0.01 * i))  # update the data
    line.set_data(x, y)
    return line,

# Makes an animation by repeatedly calling a function func
# frames can be a generator, an iterable, or a number of frames.
# interval draws a new frame every interval milliseconds.
# blit=True means only re-draw the parts that have changed.
# 在这里设置一个200帧的动画，每帧之间间隔20毫秒
anim = animation.FuncAnimation(fig, animate, init_func=init,
                               frames=200, interval=20, blit=True)
                               

# save the animation as an mp4.  This requires ffmpeg or mencoder to be
# installed.  The extra_args ensure that the x264 codec is used, so that
# the video can be embedded in html5.  You may need to adjust this for
# your system: for more information, see
# http://matplotlib.sourceforge.net/api/animation_api.html
anim.save('basic_animation.mp4', fps=30, extra_args=['-vcodec', 'libx264'])

plt.show()  # plt.show() 会一直循环播放动画

　　如果要将动画保存为mp4格式的视频文件，则需要先安装FFmpeg。FFmpeg是一套可以用来记录、转换数字音频、视频，并能将其转化为流的开源计算机程序。采用LGPL或GPL许可证。它提供了录制、转换以及流化音视频的完整解决方案。

　　在这里下载windows的版本：Download FFmpeg for Windows，解压，然后将bin目录加入系统环境变量的路径中。如：C:\Program Files\ffmpeg-3.2.2-win64-static\bin。然后测试是否配置OK: 输入ffmpeg -version

 

 

参考：

Matplotlib tutorial

Matplotlib Animation Tutorial

animation Examples

Python学习-使用matplotlib画动态多图

如何用Matplotlib画GIF动图

matplotlib绘制动画的示例

matplot 动态绘图 动画举例

Python yield使用浅析