如何更新 matplotlib 条形图动画的标题和数据？

Question

我一直在尝试创建一个水平条形图，其中标题和数据在每一帧中都会发生变化。我遇到的问题是，如果我使用blit=True，数据会更新但标题不会更新。当我使用blit=False 时，标题会改变，但数据不会改变（它只会增加）。

我已经阅读了几十个答案并尝试了所有方法，包括 set_title 和 set_text 但我处于总体损耗。感谢您的帮助。

%matplotlib
import pandas as pd
import matplotlib.pyplot as plt 
import matplotlib.animation as animation 
import numpy as np 
import csv

people = ('','Jim', 'Dan')
plt.rcdefaults()
fig, ax = plt.subplots()
y_pos = np.arange(len(people))

ax.set_xlim(0,10)
ax.set_yticks(y_pos)
ax.set_yticklabels(people)
ax.invert_yaxis() 
ax.set_xlabel('Skill')
titleList=['Basketball','Hockey']
df=[[0,5,7],[0,4,9]]
title = ax.text(0.5,0.95, "Test", bbox={'facecolor':'w', 'alpha':0.5, 'pad':5},transform=ax.transAxes, ha="center")
def animate(i):
       # Example data
    while i<2:
        ax.set_yticks(y_pos)
        ax.set_yticklabels(people)
        ax.set_xlabel(titleList[i])
        performance=df[i]
        title.set_text(str(titleList[i]))
        line= ax.barh(y_pos, performance, align='center',
                color='blue', ecolor='None')
        return line

ani = animation.FuncAnimation(fig,animate, frames=5, blit=True
                            ,interval=2000,repeat=False)

plt.show() 

Answer 1

1. 您用frames=5 调用FuncAnimation()，animate(i) 将因此尝试通过titleList[i] 设置标签和标题，但它只有2 个条目。尤其是blit=True，这会抛出错误。

2. 您的animate() 函数返回line；如果我们print(line)，我们发现它更像是一个<BarContainer object of 3 artists>而不是一条线，即barh()的三个矩形。您应该将barh() 存储在rects 然后return [rect for rect in rects]，参见this question

完整代码：

import pandas as pd
import matplotlib as mpl ## uncomment this if you are running this on a Mac
mpl.use('TkAgg')         ## and want to use blit=True
import matplotlib.pyplot as plt 
import matplotlib.animation as animation 
import numpy as np 
import csv

people = ('','Jim', 'Dan')
plt.rcdefaults()
fig, ax = plt.subplots()
y_pos = np.arange(len(people))

ax.set_xlim(0,10)
ax.set_yticks(y_pos)
ax.set_yticklabels(people)
ax.invert_yaxis() 
ax.set_xlabel('Skill')
titleList=['Basketball','Hockey']
df=[[0,5,7],[0,4,9]]
def animate(i):
   # Example data
    while i<2:
        ax.set_yticks(y_pos)
        ax.set_yticklabels(people)
        ax.set_xlabel(titleList[i])
        performance=df[i]

        title = ax.text(0.5,0.95,str(titleList[i]), bbox={'facecolor':'w', 'alpha':0.5, 'pad':5},transform=ax.transAxes, ha="center")

        rects = ax.barh(y_pos, performance, align='center',
                color='blue', ecolor='None')
        return [rect for rect in rects] + [title]


ani = animation.FuncAnimation(fig,animate, frames=2, blit=True
                            ,interval=2000,repeat=False)

plt.show()