How to reverse tuples in Python?(如何在 Python 中反转元组?)
问题描述
可能重复:
在Python中逆序遍历列表
这可能吗?不必就位,只需寻找一种反转元组的方法,以便我可以反向迭代它.
Is this possible? Doesn't have to be in place, just looking for a way to reverse a tuple so I can iterate on it backwards.
推荐答案
有两种惯用的方法:
reversed(x) # returns an iterator
或
x[::-1] # returns a new tuple
由于元组是不可变的,因此无法就地反转元组.
Since tuples are immutable, there is no way to reverse a tuple in-place.
基于@lvc 的注释,由 reversed
返回的迭代器将等效于
Building on @lvc's comment, the iterator returned by reversed
would be equivalent to
def myreversed(seq):
for i in range(len(x) - 1, -1, -1):
yield seq[i]
即它依赖于具有已知长度的序列来避免必须实际反转元组.
i.e. it relies on the sequence having a known length to avoid having to actually reverse the tuple.
至于哪个更有效,我怀疑它会是 seq[::-1]
如果你正在使用它并且元组很小,并且 当元组很大时反转
,但是python中的性能常常令人惊讶,所以测量一下!
As to which is more efficient, i'd suspect it'd be the seq[::-1]
if you are using all of it and the tuple is small, and reversed
when the tuple is large, but performance in python is often surprising so measure it!
这篇关于如何在 Python 中反转元组?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持编程学习网!
本文标题为:如何在 Python 中反转元组?


基础教程推荐
- 求两个直方图的卷积 2022-01-01
- 使用大型矩阵时禁止 Pycharm 输出中的自动换行符 2022-01-01
- 在同一图形上绘制Bokeh的烛台和音量条 2022-01-01
- 修改列表中的数据帧不起作用 2022-01-01
- PANDA VALUE_COUNTS包含GROUP BY之前的所有值 2022-01-01
- 无法导入 Pytorch [WinError 126] 找不到指定的模块 2022-01-01
- Plotly:如何设置绘图图形的样式,使其不显示缺失日期的间隙? 2022-01-01
- 包装空间模型 2022-01-01
- 在Python中从Azure BLOB存储中读取文件 2022-01-01
- PermissionError: pip 从 8.1.1 升级到 8.1.2 2022-01-01