Wrong replay memory inclusion in fileio.py

[yannikkellerde]

In _include_data_from_replay_memory in fileio.py the goal is to include random files from the most recent replay memory given by fraction_for_selection. For this, we get the filenames with os.listdir and as the code comment suggests, after inverting, the most recent files should be on top. However, os.listdir returns files in arbitrary order (see https://docs.python.org/3/library/os.html#os.listdir). I think the confusion comes from listdir being ordered by date on windows, but on my linux machine it definitely is not.

CrazyAra/engine/src/rl/fileio.py

Lines 132 to 135 in 5ec10bd

	file_names = os.listdir(self.train_dir_archive)
	# invert ordering (most recent files are on top)
	file_names = file_names[::-1]

I'd suggest explicitly sorting via os.path.getmtime:
file_names.sort(key=lambda x:os.path.getmtime(os.path.join(self.train_dir_archive,x)))

[QueensGambit]

Sorry, for the long delay you are perfectly right that os.listdir returns files/folders in arbitrary order.
I now updated the code to extract the time stamp from the folder name and sort it by the time stamp.
This should be more robust compared to os.path.getmtime as it remains the same even when the folder has been moved.
Thanks again.