用matplotlib保存scatterplot動畫

Question

我一直在試圖用matplotlib保存動畫散點圖，我寧願它不需要完全不同的代碼來查看動畫圖形和保存副本。完成保存後，該圖完美地顯示了所有數據點。

此代碼是Giggi's上Animating 3d scatterplot in matplotlib的改良版，與Matplotlib 3D scatter color lost after redraw的顏色修復從Yann's answer（因爲顏色將是我的視頻很重要，所以我要確保他們的工作）。

import matplotlib.pyplot as plt 
import matplotlib.animation as animation 
import numpy as np 
from mpl_toolkits.mplot3d import Axes3D 

FLOOR = -10 
CEILING = 10 

class AnimatedScatter(object): 
    def __init__(self, numpoints=5): 
     self.numpoints = numpoints 
     self.stream = self.data_stream() 
     self.angle = 0 

     self.fig = plt.figure() 
     self.fig.canvas.mpl_connect('draw_event',self.forceUpdate) 
     self.ax = self.fig.add_subplot(111,projection = '3d') 
     self.ani = animation.FuncAnimation(self.fig, self.update, interval=100, 
             init_func=self.setup_plot, blit=True,frames=20) 

    def change_angle(self): 
     self.angle = (self.angle + 1)%360 

    def forceUpdate(self, event): 
     self.scat.changed() 

    def setup_plot(self): 
     X = next(self.stream) 
     c = ['b', 'r', 'g', 'y', 'm'] 
     self.scat = self.ax.scatter(X[:,0], X[:,1], X[:,2] , c=c, s=200, animated=True) 

     self.ax.set_xlim3d(FLOOR, CEILING) 
     self.ax.set_ylim3d(FLOOR, CEILING) 
     self.ax.set_zlim3d(FLOOR, CEILING) 

     return self.scat, 

    def data_stream(self): 
     data = np.zeros((self.numpoints , 3)) 
     xyz = data[:,:3] 
     while True: 
      xyz += 2 * (np.random.random((self.numpoints,3)) - 0.5) 
      yield data 

    def update(self, i): 
     data = next(self.stream) 
     #data = np.transpose(data) 

     self.scat._offsets3d = (np.ma.ravel(data[:,0]) , np.ma.ravel(data[:,1]) , np.ma.ravel(data[:,2])) 

     plt.draw() 
     return self.scat, 

    def show(self): 
     plt.show() 

if __name__ == '__main__': 
    a = AnimatedScatter() 
    a.ani.save("movie.avi", codec='avi') 
    a.show() 

由此生成完全有效的.avi，但對於除軸以外的所有四秒鐘都是空白的。實際的數字總是顯示我想看到的。我如何填充保存函數的圖，就像填充正常運行的動畫一樣，還是可以在matplotlib中使用？

編輯：在更新使用分散調用（無設置範圍爲在初始化）導致的.avi顯示軸增長，顯示出的數據每次被運行，它只是不顯示在視頻本身。 我在Python 2.7.3中使用matplotlib 1.1.1rc。

Answer 1

刪除blit=True從FuncAnimation和animated=True從scatter它的工作原理。我懷疑邏輯有問題，確保只有需要更新的藝術家才能在幀之間更新/重繪（而不是僅僅重繪所有內容）。

下面就是我跑了，我得到了預期的輸出影片：

import matplotlib.pyplot as plt 
import matplotlib.animation as animation 
import numpy as np 
from mpl_toolkits.mplot3d import Axes3D 

FLOOR = -10 
CEILING = 10 

class AnimatedScatter(object): 
    def __init__(self, numpoints=5): 
     self.numpoints = numpoints 
     self.stream = self.data_stream() 
     self.angle = 0 

     self.fig = plt.figure() 
     self.fig.canvas.mpl_connect('draw_event',self.forceUpdate) 
     self.ax = self.fig.add_subplot(111,projection = '3d') 
     self.ani = animation.FuncAnimation(self.fig, self.update, interval=100, 
             init_func=self.setup_plot, frames=20) 

    def change_angle(self): 
     self.angle = (self.angle + 1)%360 

    def forceUpdate(self, event): 
     self.scat.changed() 

    def setup_plot(self): 
     X = next(self.stream) 
     c = ['b', 'r', 'g', 'y', 'm'] 
     self.scat = self.ax.scatter(X[:,0], X[:,1], X[:,2] , c=c, s=200) 

     self.ax.set_xlim3d(FLOOR, CEILING) 
     self.ax.set_ylim3d(FLOOR, CEILING) 
     self.ax.set_zlim3d(FLOOR, CEILING) 

     return self.scat, 

    def data_stream(self): 
     data = np.zeros((self.numpoints , 3)) 
     xyz = data[:,:3] 
     while True: 
      xyz += 2 * (np.random.random((self.numpoints,3)) - 0.5) 
      yield data 

    def update(self, i): 
     data = next(self.stream) 
     self.scat._offsets3d = (np.ma.ravel(data[:,0]) , np.ma.ravel(data[:,1]) , np.ma.ravel(data[:,2])) 
     return self.scat, 

    def show(self): 
     plt.show() 

if __name__ == '__main__': 
    a = AnimatedScatter() 
    a.ani.save("movie.avi", codec='avi') 
    a.show()