Question

在远程计算机上使用Matplotlib时（例如在Travis CI上），我遇到与未设置的DISPLAY环境变量相关的频繁运行时错误。根据建议，我在测试脚本的开头通过Agg设置了matplotlib.use后端，并确保没有对show()的调用。不过，我仍然会遇到以下错误：

Traceback (most recent call last):
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/nose/case.py", line 197, in runTest
    self.test(*self.arg)
  File "/home/travis/build/pymc-devs/pymc/pymc/tests/test_plots.py", line 36, in test_multichain_plots
    forestplot(ptrace, vars=['early_mean', 'late_mean'])
  File "/home/travis/build/pymc-devs/pymc/pymc/plots.py", line 325, in forestplot
    interval_plot = subplot(gs[0])
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/pyplot.py", line 896, in subplot
    fig = gcf()
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/pyplot.py", line 450, in gcf
    return figure()
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/pyplot.py", line 423, in figure
    **kwargs)
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/backends/backend_qt4agg.py", line 31, in new_figure_manager
    return new_figure_manager_given_figure(num, thisFig)
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/backends/backend_qt4agg.py", line 38, in new_figure_manager_given_figure
    canvas = FigureCanvasQTAgg(figure)
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/backends/backend_qt4agg.py", line 70, in __init__
    FigureCanvasQT.__init__( self, figure )
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/backends/backend_qt4.py", line 207, in __init__
    _create_qApp()
  File "/home/travis/anaconda/envs/testenv/lib/python2.7/site-packages/matplotlib/backends/backend_qt4.py", line 62, in _create_qApp
    raise RuntimeError('Invalid DISPLAY variable')
RuntimeError: Invalid DISPLAY variable

还有其他建议可以避免这种情况吗？

Answer 1

使用xvfb有效，请参阅Travis的 GUI & Headless browser testing文档。

P.S。 matplotlib.use('Agg')技巧对我有用。

未定义DISPLAY时使用Matplotlib

1 个答案: