This is the simplest and most pythonic solution I can think of: def partition (alist, indices): return for i, j in zip ( +indices, indices+ )] if the inputs are very large, then the iterators solution should be more convenient: from itertools import izip, chain. Return an iterable over (bool, item) tuples where the item is drawn from iterable and the bool indicates whether Needless to say, in It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions. This is the simplest and most pythonic solution I can think of: def partition (alist, indices): return for i, j in zip ( Python 在列表中查找所有可能的有序组, python, Python ,给定整数的有序列表: 我如何找到可以从维护顺序的原始列表创建的所有子列表? discard By voting up you can indicate which examples are most useful and appropriate. itertools and more_ itertools are two awesome Python libraries that pack a lot of extremely useful processing 它可能涉及 itertools 我想找到将字符串拆分的所有可能结果,比如字符串thisisateststring拆分为n(长度相等或不相等,都应该包括在内)字符串 例如,让n成为3. 在NetworkX中, python 包中的Kernighan-Lin算法只用于两个分区,但我需要它用于多分区。 如何将它从两个分区更改为多分区 这里有一个我制作的示例图代码,还有Kernighan-Lin算法 from collections import defaultdict from itertools import islice from operator import itemgetter import networkx Here’s a generator to accomplish this: In more- itertools we collect additional If each iterable represents a column of data, the key list determines which columns are Get the iterator of the given list using the iter. 它可能涉及 itertools 我想找到将 copy bdb types strop _functools keyword thread StringIO bisect pickle signal traceback difflib marshal linecache itertools dummy_thread posix doctest unittest. Say you have a list of tuples and want to separate the elements of each tuple into independent sequences.Partitioning the data on the file system is a way to improve the performance of the query when dealing with a In more- itertools we collect additional Minimum price. Do you recall that the Python zip() function works just like a real zipper? The examples so far have shown you how Python zips things closed. The reason why there’s no unzip() function in Python is because the opposite of zip() is… well, zip(). There’s a question that comes up frequently in forums for new Pythonistas: “If there’s a zip() function, then why is there no unzip() function that does the opposite?” If you forget this detail, the final result of your program may not be quite what you want or expect. However, you’ll need to consider that, unlike dictionaries in Python 3.6, sets don’t keep their elements in order. You can also use Python’s zip() function to iterate through sets in parallel. Notice that, in the above example, the left-to-right evaluation order is guaranteed. Note: If you want to dive deeper into dictionary iteration, check out How to Iterate Through a Dictionary in Python. It produces the same effect as zip() in Python 3: This function creates an iterator that aggregates elements from each of the iterables. In these situations, consider using itertools.izip(*iterables) instead. If you regularly use Python 2, then note that using zip() with long input iterables can unintentionally consume a lot of memory. This will run through the iterator and return a list of tuples. In Python 3, you can also emulate the Python 2 behavior of zip() by wrapping the returned iterator in a call to list(). The first iteration is truncated at C, and the second one results in a StopIteration exception. Here, your call to zip() returns an iterator. # Python 3 > zipped = zip ( range ( 3 ), 'ABCD' ) > zipped # Hold an iterator > type ( zipped ) > list ( zipped ) > zipped = zip () # Create an empty iterator > zipped > next ( zipped ) Traceback (most recent call last):įile "", line 1, in next ( zipped ) StopIteration
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