[Linux] no display name and no $DISPLAY environment variable 에러 해결

리눅스 환경에서 SSL을 통해 pyplot을 사용하려고 하면 아래와 같은 에러가 발생할 때가 있다.

x
Traceback (most recent call last):
  File "boston_housing.py", line 52, in <module>
    plt.figure(1)
  File "/usr/local/local/lib/python2.7/dist-packages/matplotlib/pyplot.py", line 533, in figure
    **kwargs)
  File "/usr/local/local/lib/python2.7/dist-packages/matplotlib/backend_bases.py", line 161, in new_figure_manager
    return cls.new_figure_manager_given_figure(num, fig)
  File "/usr/local/local/lib/python2.7/dist-packages/matplotlib/backends/_backend_tk.py", line 1046, in new_figure_manager_given_figure
    window = Tk.Tk(className="matplotlib")
  File "/usr/lib/python2.7/lib-tk/Tkinter.py", line 1818, in __init__
    self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use)
_tkinter.TclError: no display name and no $DISPLAY environment variable

 

이 경우에는 pyplot을 import 하기 전에 아래의 코드를 입력해주면 된다.

import matplotlib
matplotlib.use('Agg')

예시

import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
​
plt.figure(1)
plt.plot(range(1, len(average_mae_history) + 1), average_mae_history, 'r', label='mae')
plt.title('MAE')
plt.xlabel('Epochs')
plt.ylabel('Validation MAE')
plt.legend()
plt.show()
plt.savefig('boston.png')

 

출처 : https://stackoverflow.com/questions/37604289/tkinter-tclerror-no-display-name-and-no-display-environment-variable