Question

我一直在尝试使用matplotlib保存动画散点图，我更希望它不需要完全不同的代码来查看动画人物和保存副本。该图显示了保存完成后的所有数据点。

此代码是Giggi's上Animating 3d scatterplot in matplotlib的修改版本，修复了Yann's answer Matplotlib 3D scatter color lost after redraw上的颜色（因为颜色对我的视频非常重要，所以我想确保它们有效。）

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()

由此生成一个完全有效的.avi，但除了轴之外的所有四秒都是空白。实际数字总是显示我想要看到的内容。如何填充保存功能的图表的方式与填充正常运行的动画相同，或者是否可以在matplotlib中填充？

编辑：在更新中使用分散调用（不设置初始化程序中的边界）会导致.avi显示轴增长，表明数据每次都在运行，它是只是没有在视频本身上显示。我正在使用matplotlib 1.1.1rc和Python 2.7.3。

Answer 1

从blit=True移除FuncAnimation，从animated=True移除scatter，它可以正常运行。我怀疑逻辑出现了问题，确保只需要更新/重新绘制帧之间的画面（而不仅仅是重新绘制所有内容）。

以下是我的动作，我得到了预期的输出电影：

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()

使用matplotlib保存散点图动画

1 个答案: