matplotlib 图像作为饼图上的标签

Question

我找不到将标签文本移动到图像的方法。如何使用 PIL 或 imageio 从互联网检索标志图像并使用它们而不是字符串。 这是 MWE：

import matplotlib.pyplot as plt

nationalities = {
    'Fr': 5,
    'De': 10,
    'It': 3,
    'Se': 5,
    'Pl':2,
    'Cz': 3,
}

flags = {
    'Fr':'https://www.touteleurope.eu/wp-content/uploads/2022/08/drapeau-France.png',
    'De':'https://www.touteleurope.eu/wp-content/uploads/2022/07/drapeau-allemagne.png',
    'It':'https://www.touteleurope.eu/wp-content/uploads/2022/08/drapeau-Italie.png',
    'Se':'https://www.touteleurope.eu/wp-content/uploads/2022/07/1280px-Flag_of_Sweden.svg.png',
    'Pl':'https://www.touteleurope.eu/wp-content/uploads/2022/08/drapeau-Pologne.png',
    'Cz':'https://www.touteleurope.eu/wp-content/uploads/2022/08/drapeau-Republique-tcheque.png',
}

fig, ax = plt.subplots(figsize=(18,6))
plt.xticks(fontsize=20)
plt.yticks([], fontsize=20)
Countries = []
Composers = []
Flags = []
for Cnty, Cps in nationalities.items():
    Countries.append(Cnty)
    Composers.append(Cps)
    Flags.append( flags[Cnty] ) 
    nb_of_composers = 100*max(Composers)/sum(Composers)
print (str(nb_of_composers)[0:2])
#plt.pie( Composers, labels=Flags, radius=1, textprops={'size': 20}, wedgeprops={'linewidth': 1.0, 'edgecolor': 'white'}, )
plt.pie( Composers, labels=Countries, radius=1, textprops={'size': 20}, wedgeprops={'linewidth': 1.0, 'edgecolor': 'white'}, )
plt.text(s=str(nb_of_composers)[0:2]+'%', x=-0.7, y=0.3, fontsize=30, color='white')
plt.tight_layout()
plt.show()

非常感谢您的帮助！

Answer 1

您可以使用

request

+

PIL

下载图像，然后使用

imshow

添加图像:

from PIL import Image
import requests

# download the images
headers ={
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36'
}

Flags = {k: Image.open(requests.get(url, headers=headers, stream=True).raw)
         for k, url in flags.items()}

# plot the original graph
fig, ax = plt.subplots(figsize=(9,3))
plt.xticks(fontsize=20)
plt.yticks([], fontsize=20)

Countries, Composers = zip(*nationalities.items())
nb_of_composers = max(Composers)/sum(Composers)

patches, texts = plt.pie(Composers, labels=Countries, radius=1, textprops={'size': 20},
                         wedgeprops={'linewidth': 1.0, 'edgecolor': 'white'}, )
plt.text(s=f'{nb_of_composers:.0%}', x=-0.7, y=0.3, fontsize=30, color='white')

# replace the string labels with images
for t in texts:
    x, y = t.get_position()
    ax.imshow(Flags[t._text], extent=[x-0.15, x+0.15, y-0.1, y+0.1], zorder=1)
    t.set_visible(False)

plt.tight_layout()

输出：