Python combines dictionary key values and removes duplicate elements. python dictionary
Suppose there is a dictionary in python as follows:
X = {'A': '1, 2,3 ',' B ': '2, 3,4 '}
To merge:
X = {'C': '1, 2, 3, 4 '}
Three things need
Python-dictionary and python dictionary
A dictionary is a key-value data type. You can use strokes and letters to View Details of the corresponding page.
Features:1. dictionary is not required. (If the strings in the
There are generally two common practices:The first approach: using a self-implemented function:There is a Has_key () method in the property method of the Python dictionary:[Python]View PlainCopy
#生成一个字典
D = {' name ': Tom, ' age ':ten, ' Tel ':
#打印返回值
Print D.has_key (' name ')
#结果返回True
The second method: Use the In method:[
1.Python dictionary (Dictionary)A dictionary is another mutable container model and can store any type of object.each key value of the dictionary (key=>value) pair with a colon (:) split, Each pair is separated by a comma (,) , and the entire
Python [3]-dictionary dic And set, python dictionary dicsetI. dictionary dict
Dict is stored as a key-value pair. The creation method is to use braces {} and separate the key and value with a colon.
>>> d={'chen':60,'zhang':80}>>> print d{'chen': 60, 'zhang': 80}
Assignment
Summary of several methods to traverse the python Dictionary (recommended) and python dictionary
As follows:
ADict = {'key1': 'value1', 'key2': 'value2', 'key3': 'value3'} print '----------- dict -----------' for d in aDict: print "% s: % s" % (d, aDict [d]) print '----------- item -----------' for (k, v) in aDict. ite
The Python dictionary is another variable container model, and can store any type of object, such as strings, numbers, tuples, and other container models.First, create a dictionaryThe dictionary consists of a pair of keys and corresponding values. Dictionaries are also referred to as associative arrays or hash tables. The basic syntax is as follows:
Copy Co
Python-Level 7 dictionary query and python dictionary Query
1 #-*-coding: UTF-8-*-2 3 4 # job requirements: 5 # five menus of municipalities, provinces, municipalities, counties, districts, and sub-streets; 6 # Step by step to all layers 7 # exit to the previous Layer 8 # exit program at any time 9 10 11 mapChina = {12
']:", dict[' Age'];Print "dict[' School ']:", dict['School'];However, this throws an exception because the dictionary no longer exists after Del:dict['age ']:traceback (most recent call last): "test.py " in print"", dict['age ' type'is unsubscriptableProperties of Dictionary KeysA dictionary value can take any Python
A python dictionary is another mutable container model, and can store any type of object, such as strings, numbers, tuples, and other container models.First, create a dictionaryA dictionary consists of a pair of keys and corresponding values. Dictionaries are also referred to as associative arrays or hash tables. The basic syntax is as follows:Dict = {' Alice ':
Create:Dict = {' Name ': ' Zara ', ' age ': 7, ' Class ': ' First '};Delete:Del dict[' Name ']; # Delete key is ' Name ' entry dict.clear (); # Empty dictionary all Entries del dict; # Delete DictionaryProperties of Dictionary KeysA dictionary value can take any Python object without restriction, either as a
Tuple definitionA tuple is another data type, similar to a list.The tuple is identified with a "()". The inner elements are separated by commas. However, an element cannot be assigned two times, which is equivalent to a read-only list.Example:tuple = (' ABCD ', 786, 2.23, ' John ', 70.2)list = [' ABCD ', 786, 2.23, ' John ', 70.2]Tuple[2] = 1000 # tuples are illegal to applyList[2] = 1000 # is a legitimate application in the listPrint tuple * 2 # output tuple two timesDictionary definitionsThe
problem: construct a dictionary, which is a subset of another dictionaryAnswer: The simplest way is to use a dictionary derivationEG1:1.>>>prices = {' ACME ': 45.23, ' AAPL ': 612.78, ' IBM ': 205.55, ' HPQ ': 37.20, ' FB ': 10.75}>>>P1 = {Key:value for key, value in Prices.items () if value > 200}>>>p1{' AAPL ': 612.78,' IBM ': 205.55}2.dictionary derivation
In this article, we'll look at Python's Delete dictionary elements, which I'll explain in this article about how to remove the dictionary elements from Python, and how to delete all the elements in the dictionary. Well, don't say much, let's get into the article.
Delete a dictiona
The Basics tutorial introduces basic concepts, especially objects and classes.
The Advanced tutorial further expands the basic tutorial to illustrate the details of Python. Hopefully, after the advanced tutorials, you have a more comprehensive understanding of python.
As we said before, the list is a class in Python. A specific table, such as NL = [1,3,8], is a
[Python-dictionary usage] Three methods for creating a dictionary: python3
# Create an empty dictionary empty_dict = dict () print (empty_dict) # Use ** kwargs variable parameters to input keywords to create a dictionary a = dict (one = 1, two = 2, three = 3) print (a) # Pa
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.