今天小編為大家?guī)淼氖荘ython中有類似Ruby的#each_cons功能嗎?
在Ruby中你可以這樣做:
array = [1,2,3,4]
array.each_cons(2).to_a
=> [[1,2],[2,3],[3,4]]
對(duì)于此類內(nèi)容,您應(yīng)該查看的模塊是:itertools
from itertools import tee, izip
def pairwise(iterable):
"s -> (s0,s1), (s1,s2), (s2, s3), ..."
a, b = tee(iterable)
next(b, None)
return izip(a, b)
然后:
>>> list(pairwise([1, 2, 3, 4]))
[(1, 2), (2, 3), (3, 4)]
對(duì)于更通用的解決方案,請(qǐng)考慮:
def split_subsequences(iterable, length=2, overlap=0):
it = iter(iterable)
results = list(itertools.islice(it, length))
while len(results) == length:
yield results
results = results[length - overlap:]
results.extend(itertools.islice(it, length - overlap))
if results:
yield results
這允許任意長(zhǎng)度的子順序和任意重疊。用法:
>> list(split_subsequences([1, 2, 3, 4], length=2))
[[1, 2], [3, 4]]
>> list(split_subsequences([1, 2, 3, 4], length=2, overlap=1))
[[1, 2], [2, 3], [3, 4], [4]]
這樣就可以達(dá)到類似的效果了。