python 后台运行无法连接Xmanager 保存图片的方法

import glob

import time

import sys

import numpy as np

import matplotlib.pyplot as plt

import matplotlib as mpl

mpl.use('Agg')

##plt.use('Agg') 可以解决DISPLAY variable

……

ictrue =(os.path.join(out+"/"+ 'ROC.png'))

fig = plt.gcf()

fig.savefig(pictrue, format='png')

服务器重启后无法连接Xmanager,报错信息：

java.awt.AWTError: Can't connect to X11 window server using 'localhost:12.0' as the value of the DISPLAY variable

python  无法保存图片，增加上面mpl.use('Agg') 即可解决！