dict comprehension python

This article mainly introduces the application details of python dict, set, list, And tuple. For more information, see this article, the tuple application and corresponding examples help readers understand its concepts and principles. The details are as follows: 1. Dictionary (dict) Dict surrounded {}

Dict1 = {1: [111, 222], 2: [,]}Dict2 = {3: [333, 444], 4: [,]}Merge the two dictionaries to get a similar result. {1: [111, 222], 2: [333, 444], 3: [,], 4: [,]}Method 1: DictMerged1 = dict (dict1.items () + dict2.items ())Method 2: DictMerged2 = dict (dict1, ** dict2)Method 2 is equivalent: DictMerged = dict1.copy ()DictMerged. update (dict2) Or DictMerged = dict

Many of Dict's methods are similar to the list, with one by one of them coming in, and they will be compared to the list. Nesting Nesting also exists in the list, where elements are list, and in Dict, there are similar styles: >>> a_list = [[1,2,3],[4,5],[6,7]] >>> a_list[1][1] 5 >>> a_dict = {1:{"name": "Qiwsir"},2: "python", "email": "qiwsir@gmail.com"} >>> a_dict {1: {' name ': ' Qiwsir '}, 2:

Dict[key], if the key key does not exist and the value of default is not given, the Keyerror exception is thrown Del () Del dictionary variable. [Element key to delete] Note : Parameters:K: Key to search forD: Default is NULL, returns the default value if the key does not existThe function operates as follows:#!/usr/bin/env python#-*-coding:utf-8-*-

The knowledge shared in this article is the basic concept, common operations, and examples of the Dictionary (dict) in Python data types. It is very useful for you to understand the dictionary dict, I hope you will like it. I. Basic Data Types Integer: intString: str (Note: \ t is equal to a tab key)Boolean value: boolList: listList []Ancestor: tupleAncestor use

Python built-in dictionary: dict support, Dict full name dictionary, also known as map in other languages, using key-value (Key-value) storage, with extremely fast search speedUse Help (Dict) to find dict-related function actionsFor example: dt =

Python has won a lot of programmers ' pro-gaze with its beautiful syntax and convenient built-in data structures. There is a very useful data structure, which is the dictionary (dict), which is very simple to use. When it comes to traversing a dict structure, I think most people will think of the for-key in Dictobj method, and it is true that this method is appli

In Python, set represents the collection, list stands for lists, dict represents the dictionaryThe difference between set and Dict is that the dict is a storage key-value, each key is unique, the set is stored as a key relative to the dict, and the key is unique, and the lis

does not matter:{' 123 ': [1, 2, 3], # key is Str,value is List123: ' 123 ', # key is Int,value is str(' A ', ' B '): True # key is a tuple, and each element of a tuple is an immutable object, value is a Boolean}The most commonly used key is also a string, because it is most convenient to use.Two. Update DictDict is variable and can be added at any time in the network Dict Key-valueD = {' Adam ': 95,' Lisa ': 85,' Bart ': 59}Add a new classmate ' Pau

Python, with its graceful syntax and handy built-in data structure, has won the close gaze of many programmers.One of the most useful data structures is the dictionary (dict), which is very simple to use. When it comes to traversing a dict structure, I think most people will think about the method for the key in Dictobj, which is true for most cases. But not comp

Python's dict and set types 1. What Python is Dict D = { ' Adam ': +, ' Lisa ': $, ' Bart ': ', ' Paul ': 75} 2. Python's Access Dict D = { ' adam ': 59}print, ' Lisa ': $, ' Bart ': ' Adam: ', d[' Adam ']print ' Lisa: ', d[' Lisa ']print ' Bart: ', d[' Ba RT '] 3. Features of