Python 按连续顺序对整数列表进行分组

Python 按连续顺序对整数列表进行分组,python,Python,我有一个整数列表 [1,2,3,4,5,8,9,10,11,200,201,202] 我想将它们分组到一个列表列表中,其中每个子列表包含序列未被破坏的整数。像这样 [[1,5],[8,11],[200,202]] 我有一个相当笨重的工作 lSequenceOfNum = [1,2,3,4,5,8,9,10,11,200,201,202] lGrouped = [] start = 0 for x in range(0,len(lSequenceOfNum)): if x != le

我有一个整数列表

[1,2,3,4,5,8,9,10,11,200,201,202]
我想将它们分组到一个列表列表中,其中每个子列表包含序列未被破坏的整数。像这样

[[1,5],[8,11],[200,202]]
我有一个相当笨重的工作

lSequenceOfNum = [1,2,3,4,5,8,9,10,11,200,201,202]

lGrouped = []
start = 0
for x in range(0,len(lSequenceOfNum)):
    if x != len(lSequenceOfNum)-1:
        if(lSequenceOfNum[x+1] - lSequenceOfNum[x]) > 1:
            lGrouped.append([lSequenceOfNum[start],lSequenceOfNum[x]])
            start = x+1

    else:
        lGrouped.append([lSequenceOfNum[start],lSequenceOfNum[x]])
print lGrouped
这是我能做的最好的了。有没有更“蟒蛇式”的方法?谢谢..

伪代码(需要修复的错误为off by one):


我认为,在这种情况下,使用索引(如在C中,在java/python/perl/等在此基础上改进之前)而不是数组中的对象是有意义的。

以下是一个易于阅读的版本:

def close_range(el, it):
    while True:
        el1 = next(it, None)
        if el1 != el + 1:
            return el, el1
        el = el1

def compress_ranges(seq):
    iterator = iter(seq)
    left = next(iterator, None)
    while left is not None:
        right, left1 = close_range(left, iterator)
        yield (left, right)
        left = left1

list(compress_ranges([1, 2, 3, 4, 5, 8, 9, 10, 11, 200, 201, 202]))

假设列表始终按升序排列:

from itertools import groupby, count

numberlist = [1,2,3,4,5,8,9,10,11,200,201,202]

def as_range(g):
    l = list(g)
    return l[0], l[-1]

print [as_range(g) for _, g in groupby(numberlist, key=lambda n, c=count(): n-next(c))]

我意识到,与使用稍微复杂的生成器相比,手动计数要简单得多:

def ranges(seq):
    start, end = seq[0], seq[0]
    count = start
    for item in seq:
        if not count == item:
            yield start, end
            start, end = item, item
            count = item
        end = item
        count += 1
    yield start, end

print(list(ranges([1,2,3,4,5,8,9,10,11,200,201,202])))
制作:

[(1, 5), (8, 11), (200, 202)]
[(1, 5), (8, 11), (200, 202)]
这种方法非常快:

此方法(与旧方法的性能几乎完全相同):

:

这比以前快了20倍——当然,除非速度很重要,否则这不是真正的问题


使用生成器的旧解决方案:

import itertools

def resetable_counter(start):
    while True:
        for i in itertools.count(start):
            reset = yield i
            if reset:
                start = reset
                break

def ranges(seq):
    start, end = seq[0], seq[0]
    counter = resetable_counter(start)
    for count, item in zip(counter, seq): #In 2.x: itertools.izip(counter, seq)
        if not count == item:
            yield start, end
            start, end = item, item
            counter.send(item)
        end = item
    yield start, end

print(list(ranges([1,2,3,4,5,8,9,10,11,200,201,202])))
制作:

[(1, 5), (8, 11), (200, 202)]
[(1, 5), (8, 11), (200, 202)]

您可以通过三个步骤有效地完成此操作

给定

计算不连续性

     [1,2,3,4,5,8,9,10,11 ,200,201,202]
-      [1,2,3,4,5,8,9 ,10 ,11 ,200,201,202]
----------------------------------------
       [1,1,1,1,3,1,1 ,1  ,189,1  ,1]
(index) 1 2 3 4 5 6 7  8   9   10  11 
                *          *
rng = [i+1 for i,e in enumerate((x-y for x,y in zip(list1[1:],list1))) if e!=1] 
>>> rng
[5, 9]
添加边界

rng = [0] + rng + [len(list1)]
>>> rng
[0, 5, 9,12]
现在计算实际的连续性范围

[(list1[i],list1[j-1]) for i,j in zip(list2,list2[1:])]
[(1, 5), (8, 11), (200, 202)]

LB                [0,   5,    9,  12]
UB             [0, 5,   9,    12]
     -----------------------
indexes (LB,UB-1) (0,4) (5,8) (9,11)
类似问题:


这个问题很老了,但我想我还是会分享我的解决方案

假设
将numpy导入为np

a = [1,2,3,4,5,8,9,10,11,200,201,202]

np.split(a, array(np.add(np.where(diff(a)>1),1)).tolist()[0])

从跳跃的位置而不是范围的位置来考虑。您可以将结果存储在简单的整数数组中,其中每个条目都是与原始数组中的跳转相对应的索引。我认为这更简单。。。很可能这将是可重用的或库代码,您可以将所有这些封装到类的工作中。我很确定这是一个副本,尽管我现在无法查找它。@Abhijit非常确定,我测试过它。你发现它失败了吗?不确定,但o/p不是预期的。你能看看这个刚刚检查过的@Abhijit吗?这似乎是Python2.x和3.x的问题。在3.x下工作正常。。。我会试着找出原因。当然,
zip()
在2.x中不是懒惰的-你需要的-现在
[(list1[i],list1[j-1]) for i,j in zip(list2,list2[1:])]
[(1, 5), (8, 11), (200, 202)]

LB                [0,   5,    9,  12]
UB             [0, 5,   9,    12]
     -----------------------
indexes (LB,UB-1) (0,4) (5,8) (9,11)
input = [1, 2, 3, 4, 8, 10, 11, 12, 17]

i, ii, result = iter(input), iter(input[1:]), [[input[0]]]
for x, y in zip(i,ii):
    if y-x != 1:
        result.append([y])
    else:
        result[-1].append(y)

>>> result
[[1, 2, 3, 4], [8], [10, 11, 12], [17]]

>>> print ", ".join("-".join(map(str,(g[0],g[-1])[:len(g)])) for g in result)
1-4, 8, 10-12, 17

>>> [(g[0],g[-1])[:len(g)] for g in result]
[(1, 4), (8,), (10, 12), (17,)]
a = [1,2,3,4,5,8,9,10,11,200,201,202]

np.split(a, array(np.add(np.where(diff(a)>1),1)).tolist()[0])