Python:(1,2,3) 和 [1,2,3] 有什么区别，我应该什么时候使用它们?
问题描述
在很多地方，(1,2,3)(元组)和[1,2,3](列表)可以互换使用.
In many places, (1,2,3) (a tuple) and [1,2,3] (a list) can be used interchangeably.
我什么时候应该使用其中一种，为什么?
When should I use one or the other, and why?
解决方案
来自 Python 常见问题解答:
列表和元组虽然在许多方面相似，但通常以根本不同的方式使用.元组可以被认为类似于 Pascal 记录或 C 结构；它们是相关数据的小集合，可能是不同类型的，作为一个组进行操作.例如，笛卡尔坐标适当地表示为两个或三个数字的元组.
Lists and tuples, while similar in many respects, are generally used in fundamentally different ways. Tuples can be thought of as being similar to Pascal records or C structs; they're small collections of related data which may be of different types which are operated on as a group. For example, a Cartesian coordinate is appropriately represented as a tuple of two or three numbers.
另一方面，列表更像其他语言中的数组.它们倾向于持有不同数量的对象，所有这些对象都具有相同的类型并且被一个接一个地操作.
Lists, on the other hand, are more like arrays in other languages. They tend to hold a varying number of objects all of which have the same type and which are operated on one-by-one.
通常按照惯例，您不会仅仅根据其(不)可变性来选择列表或元组.您可以为完全不同的数据片段的小集合选择一个元组，其中成熟的类过于重量级，而为任何合理大小的集合选择一个列表，其中您拥有一组同质数据.
Generally by convention you wouldn't choose a list or a tuple just based on its (im)mutability. You would choose a tuple for small collections of completely different pieces of data in which a full-blown class would be too heavyweight, and a list for collections of any reasonable size where you have a homogeneous set of data.
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