python - absl.flags 错误 : Trying to access flag before flags were parsed

Question

我正在尝试解析这个标志“dataroot”(字符串类型)。

将此视为演示代码:

from absl import flags
from absl.flags import FLAGS

flags.DEFINE_string('dataroot',"D:\College",'path to root folder of dataset')


if __name__ == '__main__':

    #Hyperparameter
    # Root directory for dataset
    dataroot = FLAGS.dataroot

这就是错误的来源:

Traceback (most recent call last):
  File "d:/Github/cloned repo/Image-Restoration-in-Occluded-Images-using-GANs/main.py", line 49, in <module>
    dataroot = FLAGS.dataroot
  File "D:\anaconda\lib\site-packages\absl\flags\_flagvalues.py", line 498, in __getattr__
    raise _exceptions.UnparsedFlagAccessError(error_message)
absl.flags._exceptions.UnparsedFlagAccessError: Trying to access flag --dataroot before flags were parsed.

知道我哪里出错了吗？

Answer 1

在访问 FLAGS.xxx 之前，您需要告诉标志库使用 FLAGS(sys.argv) 解析 argv。调用 app.run() 是一种隐式执行此操作的方法。

通过显式调用 FLAGS(sys.argv) 而不使用 app.run() 的示例:

  from absl import flags
  import sys
  flags.DEFINE_string('dataroot',"D:\\College",'path to root folder of dataset')
  FLAGS = flags.FLAGS
  FLAGS(sys.argv)   # need to explicitly to tell flags library to parse argv before you can access FLAGS.xxx
  dataroot = FLAGS.dataroot