matplotlib画图报错ImportError: No module named 'PyQt4'

今天用matplotlib画图发现并不能画出来，还报错

import matplotlib.pyplot as plt
  File "D:\Anaconda3\lib\site-packages\matplotlib\pyplot.py", line 114, in <module>
    _backend_mod, new_figure_manager, draw_if_interactive, _show = pylab_setup()
  File "D:\Anaconda3\lib\site-packages\matplotlib\backends\__init__.py", line 32, in pylab_setup
    globals(),locals(),[backend_name],0)
  File "D:\Anaconda3\lib\site-packages\matplotlib\backends\backend_qt5agg.py", line 16, in <module>
    from .backend_qt5 import QtCore
  File "D:\Anaconda3\lib\site-packages\matplotlib\backends\backend_qt5.py", line 31, in <module>
    from .qt_compat import QtCore, QtGui, QtWidgets, _getSaveFileName, __version__
  File "D:\Anaconda3\lib\site-packages\matplotlib\backends\qt_compat.py", line 137, in <module>
    from PyQt4 import QtCore, QtGui
ImportError: No module named 'PyQt4'

ok，那我就去查一下，有一个方法是这样的

import matplotlib as mpl

mpl.use(‘Agg’)

这回没报错了，但是根本没有图

我想了一下，把backend打印出来看一下，发现是Qt5Agg

import matplotlib
# import matplotlib.pyplot as plt
backend = matplotlib.get_backend()
print(backend)

想着试试别，因为之前做过类似的

大概知道有“TkAgg”，“WXAgg”，“Qt5Agg”，其他类型没有接触过

就试着换一下，结果“TkAgg”就成了

import matplotlib
# import matplotlib.pyplot as plt
backend = matplotlib.get_backend()
print(backend)
matplotlib.use('TkAgg')

所以遇到这个问题的时候不要着急安装这安装那的