Como classificar arquivos enormes com o Python?
Eu encontrei alguns deste código promissor em activestate.com para classificar arquivos enormes. Estou tentando executá-lo no interpretador Python 2.6.5 padrão no Ubuntu 10.04. Quando tento executá-lo em um arquivo de teste pequeno, recebo o rastreio de erro abaixo. Eu pedi ajuda em activestate.com, mas este tópico está em silêncio há mais de 18 meses. Existe alguém aqui que veja uma solução óbvia?
Obrigado.
## {{{ http://code.activestate.com/recipes/576755/ (r3)
# based on Recipe 466302: Sorting big files the Python 2.4 way
# by Nicolas Lehuen
import os
from tempfile import gettempdir
from itertools import islice, cycle
from collections import namedtuple
import heapq
Keyed = namedtuple("Keyed", ["key", "obj"])
def merge(key=None, *iterables):
# based on code posted by Scott David Daniels in c.l.p.
# http://groups.google.com/group/comp.lang.python/msg/484f01f1ea3c832d
if key is None:
keyed_iterables = iterables
else:
keyed_iterables = [(Keyed(key(obj), obj) for obj in iterable)
for iterable in iterables]
for element in heapq.merge(*keyed_iterables):
yield element.obj
def batch_sort(input, output, key=None, buffer_size=32000, tempdirs=None):
if tempdirs is None:
tempdirs = []
if not tempdirs:
tempdirs.append(gettempdir())
chunks = []
try:
with open(input,'rb',64*1024) as input_file:
input_iterator = iter(input_file)
for tempdir in cycle(tempdirs):
current_chunk = list(islice(input_iterator,buffer_size))
if not current_chunk:
break
current_chunk.sort(key=key)
output_chunk = open(os.path.join(tempdir,'%06i'%len(chunks)),'w+b',64*1024)
chunks.append(output_chunk)
output_chunk.writelines(current_chunk)
output_chunk.flush()
output_chunk.seek(0)
with open(output,'wb',64*1024) as output_file:
output_file.writelines(merge(key, *chunks))
finally:
for chunk in chunks:
try:
chunk.close()
os.remove(chunk.name)
except Exception:
pass
Rastreio de erro:
Traceback (most recent call last):
File "./batch_sort.py", line 108, in <module>
batch_sort(args[0],args[1],options.key,options.buffer_size,options.tempdirs)
File "./batch_sort.py", line 54, in batch_sort
output_file.writelines(merge(key, *chunks))
File "./batch_sort.py", line 30, in merge
yield element.obj
AttributeError: 'str' object has no attribute 'obj'