一个非常好的例子是Python DB API里的fetchmany()方法,他把查询的结果通过list of tuples的方式传了回来,大家可以想象一下,查询数据库返回的多笔记录,每一笔记录他的字段结构都是相同的(也就是他是相同类型的,homogeneous),而对于其中的某条记录里的各字段,他们各自都有自己的语义(也就是他是不同类型的,hete...
https://docs.python.org/zh-cn/3/library/stdtypes.html#sequence-types-list-tuple-range 翻译部分观点如下: 1、Tuples are immutable, lists are mutable. 元组是不可变的, 而列表是可变的。 2、Tuples are heterogeneous data structures, lists are homogeneous sequences. Tuples have structure, lists hav...
元组是不可修改的,通常包含一个序列的异构(heterogeneous)的元素,这些元素通过解包(见本节后面的内容)或索引来访问(在namedtuples中,甚至可以通过属性来访问)。list是可修改的,list的元素通常是同构的(homogeneous),并通过遍历list来访问。 构建包含0个或1个元素的元组是一个特别的问题:Python 语法对此有额外的兼容来...
Arrays in python can only contain elements of same data types i.e., data type of array should be homogeneous. It is a thin wrapper around C language arrays and consumes far less memory than lists. Lists in python can contain elements of different data types i.e., data type of lists ca...
In these examples, you create a list of integer numbers and then a tuple of similar objects. In both cases, the contained objects have the same data type. So, they’re homogeneous.The elements of a list or tuple can also be of heterogeneous data types:...
Use tuples for heterogeneous, unchanging data and lists for homogeneous, modifiable collections. Best Practices Use for fixed data:Prefer tuples for collections that won't change As dictionary keys:Use tuples (with hashable elements) as keys ...
也就是说,pandas 更适合列成表的 (tabular) 或者是多种类的 (heterogeneous) 数据,而 numpy 更适合同种类的 (homogeneous) 数据。 让我们开始吧! Introduction to pandas Data Structures# pandas 中两类最常用的数据结构就是 Series 和 DataFrame。
list(列表) 创建 方法一(直接创建) #直接创建 allList=["Tom",True,False,3.14,500] #输出:['Tom', True, False, 3.14, 500] print(allList) 方法二(通过迭代对象,使用构造方法创建。) 先来看一下官方文档对list构造方法的描述: def __init__(self, seq=()): # known special case of list.__...
同类Homogeneous vs. 异类 Heterogeneous 容器类型 强制类型转换 Coercion 可变性和对象标识 MUTABILITY & OBJECT IDENTITY Python 命名规范 程序员的窘境 下图给出各种语言的优劣势。解释性语言生产效率高,但是性能相对低一些。而编译性语言性能高,但是生产效率偏低。这也是码农们的烦恼,应该选择哪门语言呢?既然是 Python...
immutablesequences, typically used to store collections of heterogeneous(异种的,不同成分的) data (such as the 2-tuples produced by the enumerate() built-in). Tuples are also used for cases where an immutable sequence of homogeneous data is needed (such as allowing storage in a set or ...