FuncAnimation 被调用太多次

Question

这是的延续。我注意到用于更新饼图的值不正确。我在名为 update 的 FuncAnimation 函数中有一个列表 z 正在使用 num 迭代器进行更新。这是我正在使用的代码：

import numpy as np
import matplotlib.animation as animation
from matplotlib import pyplot as plt 

numbers = [[6.166, 5.976, 3.504, 7.104, 5.14],
 [7.472, 5.888, 3.264, 6.4825, 7.168],
 [7.5716, 9.936, 3.6, 8.536, 2.808],
 [2.604, 2.296, 0.0, 6.144, 4.836],
 [7.192, 4.932, 0.0, 6.016, 8.808],
 [7.192, 5.5755, 3.694, 9.376, 9.108],
 [7.63616, 5.912, 3.968, 6.672, 3.192],
 [3.41049, 5.44, 4.004, 7.212, 3.6954],
 [4.3143, 6.364, 3.584, 7.44, 5.78],
 [4.992, 3.9692, 4.272, 0.0, 2.528]]
numbers = np.array(numbers)

colors = ["yellow", "red", "purple", "blue", "green"]
explode = [0.01, 0.01, 0.01, 0.01, 0.01]
labels = ["DM", "Bard", "Warlock", "Paladin", "Ranger"]
z = np.array([0,0,0,0,0]).astype(np.float)

fig,ax = plt.subplots()
y = []
def update(num):
    global y
    global z
    ax.clear()
    ax.axis('equal')     
    z += numbers[num]
    y.append(z)
    
    #output of different vairables#
    print(num, z, sum(z), len(y))

    pie = ax.pie(z, explode=explode, labels=labels, colors=colors, 
                 autopct='%1.1f%%', shadow=True, startangle=140)
    ax.set_title(sum(z))    
    
ani = animation.FuncAnimation(fig, update, frames=range(10), repeat=False)
ani.save('test.gif', writer='pillow', fps=1)

print() 函数的输出如下所示：

0 [6.166 5.976 3.504 7.104 5.14 ] 27.89 1
0 [12.332 11.952  7.008 14.208 10.28 ] 55.78 2
1 [19.804  17.84   10.272  20.6905 17.448 ] 86.05450000000002 3
2 [27.3756 27.776  13.872  29.2265 20.256 ] 118.5061 4
3 [29.9796 30.072  13.872  35.3705 25.092 ] 134.3861 5
4 [37.1716 35.004  13.872  41.3865 33.9   ] 161.3341 6
5 [44.3636 40.5795 17.566  50.7625 43.008 ] 196.27959999999996 7
6 [51.99976 46.4915  21.534   57.4345  46.2    ] 223.65975999999995 8
7 [55.41025 51.9315  25.538   64.6465  49.8954 ] 247.42165 9
8 [59.72455 58.2955  29.122   72.0865  55.6754 ] 274.90395 10
9 [64.71655 62.2647  33.394   72.0865  58.2034 ] 290.66515 11
0 [70.88255 68.2407  36.898   79.1905  63.3434 ] 318.55514999999997 12

打印输出显示 numbers[0] 被添加到自身 before num 迭代器增加 1。之后，它按预期工作其中 numbers[1] 到 numbers[9] 相加。但同样，由于某种原因，numbers[0] 被添加到 numbers[9]。

生成的 gif 的第一帧显示此数据： [12.332 11.952 7.008 14.208 10.28 ] 55.78 最后一帧显示此数据：[64.71655 62.2647 33.394 72.0865 58.2034 ] 290.66515 这没关系，因为这是循环应该停止的地方。

我想知道在这种情况下我做错了什么；如何纠正 num 的意外行为？

Answer 1

如果没有将 init_func= 传递给 FuncAnimation，它将使用动画函数本身作为初始状态，这会导致你的双重 0。 The documentation states:

init_func : callable, optional

A function used to draw a clear frame. If not given, the results of drawing from the first item in the frames sequence will be used. This function will be called once before the first frame.

您可以简单地传递一个空函数来解决问题。

def init():
    pass

(...)

ani = animation.FuncAnimation(fig, update, frames=range(10), init_func=init, repeat=False)

FuncAnimation 被调用太多次

FuncAnimation being called too many times

python

numpy

matplotlib

matplotlib-animation