Matplotlib 长期构建字体缓存？

Posted 2023-03-12

【中文标题】Matplotlib 长期构建字体缓存？

【英文标题】：Matplotlib is building the font cache for long time?

【发布时间】：2016-12-28 12:06:03

【问题描述】：

我在 OSX 上使用 python 2.7 (miniconda)。这是我的代码，即使在 30 分钟后，程序也不会运行完成。这是输出，有什么想法有什么问题吗？

源代码，

#!/usr/bin/python
# -*- coding: utf-8 -*-

"""
=========================================================
Logistic Regression 3-class Classifier
=========================================================

Show below is a logistic-regression classifiers decision boundaries on the
`iris <http://en.wikipedia.org/wiki/Iris_flower_data_set>`_ dataset. The
datapoints are colored according to their labels.

"""
print(__doc__)


# Code source: Gaël Varoquaux
# Modified for documentation by Jaques Grobler
# License: BSD 3 clause

import numpy as np
import matplotlib.pyplot as plt
from sklearn import linear_model, datasets

# import some data to play with
iris = datasets.load_iris()
X = iris.data[:, :2]  # we only take the first two features.
Y = iris.target

h = .02  # step size in the mesh

logreg = linear_model.LogisticRegression(C=1e5)

# we create an instance of Neighbours Classifier and fit the data.
logreg.fit(X, Y)

# Plot the decision boundary. For that, we will assign a color to each
# point in the mesh [x_min, m_max]x[y_min, y_max].
x_min, x_max = X[:, 0].min() - .5, X[:, 0].max() + .5
y_min, y_max = X[:, 1].min() - .5, X[:, 1].max() + .5
xx, yy = np.meshgrid(np.arange(x_min, x_max, h), np.arange(y_min, y_max, h))
Z = logreg.predict(np.c_[xx.ravel(), yy.ravel()])

# Put the result into a color plot
Z = Z.reshape(xx.shape)
plt.figure(1, figsize=(4, 3))
plt.pcolormesh(xx, yy, Z, cmap=plt.cm.Paired)

# Plot also the training points
plt.scatter(X[:, 0], X[:, 1], c=Y, edgecolors='k', cmap=plt.cm.Paired)
plt.xlabel('Sepal length')
plt.ylabel('Sepal width')

plt.xlim(xx.min(), xx.max())
plt.ylim(yy.min(), yy.max())
plt.xticks(())
plt.yticks(())

plt.show()

错误输出，

/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/font_manager.py:273: UserWarning: Matplotlib is building the font cache using fc-list. This may take a moment.
  warnings.warn('Matplotlib is building the font cache using fc-list. This may take a moment.')

编辑1，删除~/.matplotlib/下的文件后报错，

/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/font_manager.py:273: UserWarning: Matplotlib is building the font cache using fc-list. This may take a moment.
  warnings.warn('Matplotlib is building the font cache using fc-list. This may take a moment.')
Traceback (most recent call last):
  File "/Users/foo/personal/law/justech/featureExtraction/testLogisticRegression.py", line 22, in <module>
    import matplotlib.pyplot as plt
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/pyplot.py", line 29, in <module>
    import matplotlib.colorbar
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/colorbar.py", line 34, in <module>
    import matplotlib.collections as collections
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/collections.py", line 27, in <module>
    import matplotlib.backend_bases as backend_bases
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/backend_bases.py", line 62, in <module>
    import matplotlib.textpath as textpath
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/textpath.py", line 15, in <module>
    import matplotlib.font_manager as font_manager
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/font_manager.py", line 1421, in <module>
    _rebuild()
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/font_manager.py", line 1406, in _rebuild
    fontManager = FontManager()
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/font_manager.py", line 1044, in __init__
    self.ttffiles = findSystemFonts(paths) + findSystemFonts()
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/font_manager.py", line 324, in findSystemFonts
    for f in get_fontconfig_fonts(fontext):
  File "/Users/foo/miniconda2/lib/python2.7/site-packages/matplotlib/font_manager.py", line 276, in get_fontconfig_fonts
    stderr=subprocess.PIPE)
  File "/Users/foo/miniconda2/lib/python2.7/subprocess.py", line 710, in __init__
    errread, errwrite)
  File "/Users/foo/miniconda2/lib/python2.7/subprocess.py", line 1334, in _execute_child
    child_exception = pickle.loads(data)
  File "/Users/foo/miniconda2/lib/python2.7/pickle.py", line 1388, in loads
    return Unpickler(file).load()
  File "/Users/foo/miniconda2/lib/python2.7/pickle.py", line 864, in load
    dispatch[key](self)
  File "/Users/foo/miniconda2/lib/python2.7/pickle.py", line 886, in load_eof
    raise EOFError
EOFError

【问题讨论】：

matplotlib taking time when being imported的可能重复

@tom，尝试了解决方案并遇到了其他错误。请参阅编辑 1 部分。我觉得我遇到的问题与您在另一篇文章中提到的不同。

【参考方案1】：

很可能 matplotlib 1.5.1 已安装在您的机器上，您可能会收到警告：

/usr/lib/python2.7/dist-packages/matplotlib/font_manager.py:273: UserWarning: Matplotlib is building the font cache using fc-list. This may take a moment.
  warnings.warn('Matplotlib is building the font cache using fc-list. This may take a moment.')

要摆脱此警告，请通过以下方式升级 matplotlib：

*sudo pip install --upgrade matplotlib*