#!/usr/bin/env python

import aselite

from sys import argv, exit

if len(argv) < 3:
    print('usage: center.py FILE STDDEV')
    print('       randomly displaces the atoms in FILE by a gaussian with') 
    print('       a standard deviation of STDDEV') 
    print('')
    exit(0)
    
filename = argv[1]
stddev = float(argv[2])
atoms = aselite.read_any(filename)
atoms.rattle(stddev)

atoms.write(filename)