Python Basic Data classification method

First, the memory model

Classification of variables based on their organization in memory

The type of Python, like most other languages, can hold one or more values. A type that can hold a single literal object we call it atomic or scalar storage , those types that can hold multiple objects, which we call container storage . (Container objects are sometimes referred to as compound objects in a document, but they do not just refer to types, but also include objects such as class instances)

Storage Model

category	Python Type
Scalar/Atomic Type	Numeric (all numeric type) strings (all text)
Container Type	Lists, tuples, dictionaries

Second, the Access model

Classify data types according to how you access the data that we store. There are three ways to access the model: direct access, order, and mapping .

Pyth On data type	Access model
Digital	& nbsp   Direct access to
strings, lists, tuples	sequential access
Dictionary	map access

Third, update the model

Some types allow their values to be updated, while others are not allowed. (value is changed)

Data Type	Storage Model	Update Model	Access Model
Digital	Scalar	Cannot be changed	Direct access
String	Scalar	Cannot be changed	Sequential access
List	Container	Can be changed	Sequential access
Meta-group	Container	Cannot be changed	Sequential access
Dictionary	Container	Can be changed	Map Access

Add:

A dictionary is an unordered storage structure that includes a keyword (key) and a value that corresponds to a keyword (value). The format of the dictionary is: dictionary = {Key:value}. A keyword is an immutable type , such as a string, an integer, a tuple that contains only immutable objects, and a list that cannot be used as a keyword. If there is a keyword pair in the list, you can construct the dictionary directly with Dict ().

The only difference between set and dict is that it does not store the corresponding value, but the set principle is the same as the dict, so it is also not possible to put mutable objects, because it is not possible to determine whether the two Mutable objects are equal, and there is no guarantee that there will be no duplicate elements inside the set. Try putting the list in set to see if it will give an error.

Benbow in the dictionary (dict) and set (set) is somewhat ambiguous, if you read the blog has suggestions or ideas, you can discuss together.

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Python Basic Data classification method