def chunk(lst):
    out = []
    for x in xrange(2, len(lst) + 1):
        if not len(lst) % x:
            factor = len(lst) / x
            break
    while lst:
        out.append([lst.pop(0) for x in xrange(factor)])
    return out

由于我必须这样做，下面是我的解决方案，给出了一个生成器和一个批量大小：

def pop_n_elems_from_generator(g, n):
    elems = []
    try:
        for idx in xrange(0, n):
            elems.append(g.next())
        return elems
    except StopIteration:
        return elems

[AA[i:i+SS] for i in range(len(AA))[::SS]]

其中AA是数组，SS是块大小。例如：

>>> AA=range(10,21);SS=3
>>> [AA[i:i+SS] for i in range(len(AA))[::SS]]
[[10, 11, 12], [13, 14, 15], [16, 17, 18], [19, 20]]
# or [range(10, 13), range(13, 16), range(16, 19), range(19, 21)] in py3

要扩展py3中的范围，请执行以下操作

(py3) >>> [list(AA[i:i+SS]) for i in range(len(AA))[::SS]]
[[10, 11, 12], [13, 14, 15], [16, 17, 18], [19, 20]]

itertools模块中的配方提供了两种方法来实现这一点，具体取决于您希望如何处理最终的奇数大小的批次（保留它、用填充值填充它、忽略它或引发异常）：

from itertools import islice, izip_longest

def batched(iterable, n):
    "Batch data into lists of length n. The last batch may be shorter."
    # batched('ABCDEFG', 3) --> ABC DEF G
    it = iter(iterable)
    while True:
        batch = list(islice(it, n))
        if not batch:
            return
        yield batch

def grouper(iterable, n, *, incomplete='fill', fillvalue=None):
    "Collect data into non-overlapping fixed-length chunks or blocks"
    # grouper('ABCDEFG', 3, fillvalue='x') --> ABC DEF Gxx
    # grouper('ABCDEFG', 3, incomplete='strict') --> ABC DEF ValueError
    # grouper('ABCDEFG', 3, incomplete='ignore') --> ABC DEF
    args = [iter(iterable)] * n
    if incomplete == 'fill':
        return zip_longest(*args, fillvalue=fillvalue)
    if incomplete == 'strict':
        return zip(*args, strict=True)
    if incomplete == 'ignore':
        return zip(*args)
    else:
        raise ValueError('Expected fill, strict, or ignore')

这个问题让我想起Raku（以前的Perl6）.comb（n）方法。它将字符串分成n个大小的块。（还有更多，但我会省略细节。）

在Python3中实现一个类似的函数作为lambda表达式非常简单：

comb = lambda s,n: (s[i:i+n] for i in range(0,len(s),n))

然后你可以这样称呼它：

some_list = list(range(0, 20))  # creates a list of 20 elements
generator = comb(some_list, 4)  # creates a generator that will generate lists of 4 elements
for sublist in generator:
    print(sublist)  # prints a sublist of four elements, as it's generated

当然，您不必将生成器分配给变量；你可以直接这样循环：

for sublist in comb(some_list, 4):
    print(sublist)  # prints a sublist of four elements, as it's generated

另外，此comb（）函数还对字符串进行操作：

list( comb('catdogant', 3) )  # returns ['cat', 'dog', 'ant']

一种老式的方法，不需要itertools，但仍然可以使用任意生成器：

def chunks(g, n):
  """divide a generator 'g' into small chunks
  Yields:
    a chunk that has 'n' or less items
  """
  n = max(1, n)
  buff = []
  for item in g:
    buff.append(item)
    if len(buff) == n:
      yield buff
      buff = []
  if buff:
    yield buff