# Copyright (C) 2009, 2010, 2011 Roman Zimbelmann <romanz@lavabit.com>
# This software is distributed under the terms of the GNU GPL version 3.
def human_readable(byte, separator=' '):
"""
Convert a large number of bytes to an easily readable format.
>>> human_readable(54)
'54 B'
>>> human_readable(1500)
'1.46 K'
>>> human_readable(2 ** 20 * 1023)
'1023 M'
"""
# I know this can be written much shorter, but this long version
# performs much better than what I had before. If you attempt to
# shorten this code, take performance into consideration.
if byte <= 0:
return '0'
if byte < 2**10:
return '%d%sB' % (byte, separator)
if byte < 2**10 * 999:
return '%.3g%sK' % (byte / 2**10.0, separator)
if byte < 2**20:
return '%.4g%sK' % (byte / 2**10.0, separator)
if byte < 2**20 * 999:
return '%.3g%sM' % (byte / 2**20.0, separator)
if byte < 2**30:
return '%.4g%sM' % (byte / 2**20.0, separator)
if byte < 2**30 * 999:
return '%.3g%sG' % (byte / 2**30.0, separator)
if byte < 2**40:
return '%.4g%sG' % (byte / 2**30.0, separator)
if byte < 2**40 * 999:
return '%.3g%sT' % (byte / 2**40.0, separator)
if byte < 2**50:
return '%.4g%sT' % (byte / 2**40.0, separator)
if byte < 2**50 * 999:
return '%.3g%sP' % (byte / 2**50.0, separator)
if byte < 2**60:
return '%.4g%sP' % (byte / 2**50.0, separator)
return '>9000'
if __name__ == '__main__':
import doctest
doctest.testmod()