prelude.py 文件源码

def iwindowed(iterable, n):
    '''
    Take successive n-tuples from an iterable using a sliding window
    '''
    # Take n copies of the iterable
    iterables = tee(iterable, n)

    # Advance each to the correct starting position
    for step, it in enumerate(iterables):
        for s in range(step):
            next(it)

    # Zip the modified iterables and yield the elements as a genreator
    # NOTE: not using zip longest as we want to stop when we reach the end
    for t in zip(*iterables):
        yield t