Cartopy and matplotlib TypeError: unhashable type: 'MultiLineString'

Question

我正在尝试按照 Cartopy 官方网站上提供的示例来尝试使用 Cartopy。它们都正常工作，但第一个

import cartopy.crs as ccrs
import matplotlib.pyplot as plt

ax = plt.axes(projection=ccrs.PlateCarree())
ax.coastlines()

plt.show()

所有线路都正常工作，但是一旦我 运行 plt.show() 命令，我就会收到以下错误消息：

Exception in Tkinter callback
Traceback (most recent call last):
  File "/usr/lib/python2.7/lib-tk/Tkinter.py", line 1539, in __call__
    return self.func(*args)
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_tkagg.py", line 278, in resize
    self.show()
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_tkagg.py", line 349, in draw
    FigureCanvasAgg.draw(self)
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_agg.py", line 469, in draw
    self.figure.draw(self.renderer)
  File "/usr/lib/python2.7/dist-packages/matplotlib/artist.py", line 59, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/matplotlib/figure.py", line 1079, in draw
    func(*args)
  File "/usr/lib/python2.7/dist-packages/matplotlib/artist.py", line 59, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/home/mrvaita/python_workspace/gis_venv/local/lib/python2.7/site-packages/cartopy/mpl/geoaxes.py", line 359, in draw
    inframe=inframe)
  File "/usr/lib/python2.7/dist-packages/matplotlib/artist.py", line 59, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/matplotlib/axes/_base.py", line 2092, in draw
    a.draw(renderer)
  File "/usr/lib/python2.7/dist-packages/matplotlib/artist.py", line 59, in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/home/mrvaita/python_workspace/gis_venv/local/lib/python2.7/site-packages/cartopy/mpl/feature_artist.py", line 113, in draw
    {})
  File "/usr/lib/python2.7/weakref.py", line 433, in setdefault
    return self.data.setdefault(ref(key, self._remove),default)
TypeError: unhashable type: 'MultiLineString'

有人知道吗？ 我的matplotlib版本是1.4.2，Cartopy版本是0.13.0

非常感谢您的帮助。

Answer 1

这是 https://github.com/SciTools/cartopy/issues/682 的 Cartopy 问题跟踪器上报告的一个问题。基本上，Shapely 在 1.5.12 和 1.5.13 之间改变了几何的可散列性。在我们发布新版本的 cartopy 之前，解决方法是将 shapely 的安装降级到 1.5.12。

HTH