filter_in.py
A script to remove any atoms outside of a box around (0, 0, 0).
$ filter_in.py -h
usage: filter_in.py [-h] -s SIDE [input_file] [output_file]
positional arguments:
input_file by default, reads from stdin
output_file by default, writes to stdout
optional arguments:
-h, --help show this help message and exit
-s SIDE, --side SIDE