Detailed explanation of set syntax in python3

Y2J
Release: 2017-05-03 15:45:35
Original
1522 people have browsed it

This article mainly summarizes the relevant information about the syntax of set (set) in python3. The article gives detailed sample code, which has certain reference value for everyone. Friends who need it can take a look below.

Introduction

set Gu Mingsiyi is a set, and the elements of the set are unique and unordered. Putting some elements in a { ​​} forms a set. The set can be of multiple data types (but not lists, sets, dictionaries, but can be tuples)

A set is an unordered non-repeating element of sets. Basic functionality includes relationship testing and elimination of duplicate elements. Set objects also support mathematical operations such as union, intersection, difference and sysmmetric difference.

Braces or the set() function can be used to create a set. Note: To create an empty collection, you must use set() instead of {}. {} is used to create an empty dictionary;

The specific syntax is summarized as follows.

add (add elements)

name = set(['Tom','Lucy','Ben'])
name.add('Juny')
print(name)

#输出:{'Lucy', 'Juny', 'Ben', 'Tom'}
Copy after login

clear (clear all elements)

name = set(['Tom','Lucy','Ben'])
name.clear()
print(name)

#输出:set()
Copy after login

copy (copy set collection)

name = set(['Tom','Lucy','Ben'])
new_name = name.copy()
print(new_name)

#输出:{'Tom', 'Lucy', 'Ben'}
Copy after login

difference (return Different elements in two or more sets and generate a new set)

A = set([2,3,4,5])
B = set([3,4])
C = set([2])
n = n1.difference(n2,n3)
print(n)

#输出:{5}
#返回A集合里面,在B和C集合中没有的元素,并生成新的集合
Copy after login

difference_update (Delete the elements in set A that exist in set B.)

A = set([2,3,4,5])
B = set([4,5])
A.difference_update(B)
print(A)

#输出:{2, 3}
Copy after login

discard (move Remove elements)

n = set([2,3,4])
n.discard(3)
print(n)

#输出:{2, 4}
Copy after login

intersection(Get the intersection and generate a new set)

n1 = set([2,3,4,5])
n2 = set([4,5,6,7])
n = n1.intersection(n2)
print(n)

#输出:{4, 5}
Copy after login

intersection_update(Get the intersection and modify the original set)

n1 = set([2,3,4,5])
n2 = set([4,5,6,7])
n1.intersection_update(n2)
print(n1)

#输出:{4, 5}
Copy after login

isdisjoint(Judge the intersection, Returns False if yes, True if not)

n1 = set([2,3,4,5])
n2 = set([4,5,6,7])
print(n1.isdisjoint(n2))

#输出:False
Copy after login

issubset(Judge subset)

A = set([2,3])
B = set([2,3,4,5])
print(A.issubset(B))

#输出:True
#A是B的子集
Copy after login

issuperset(Judge parent set)

A = set([2,3])
B = set([2,3,4,5])
print(B.issuperset(A))

# 输出:True
#B是A的父集
Copy after login

pop(Randomly remove an element)

n = set([2,3,4,5])
n1 = n.pop()
print(n,n1)

# 输出:{3, 4, 5} 2
Copy after login

remove(remove the specified element)

n = set([2,3,4,5])
n.remove(2)
print(n)

# 输出:{3, 4, 5}
Copy after login

symmetric_difference(take the intersection and generate a new set)

A = set([2,3,4,5])
B = set([4,5,6,7])
print(A.symmetric_difference(B))

# 输出:{2, 3, 6, 7}
Copy after login

symmetric_difference_update(take the intersection and change the original set)

A = set([2,3,4,5])
B = set([4,5,6,7])
A.symmetric_difference_update(B)
print(A)

# 输出:{2, 3, 6, 7}
Copy after login

union (take the union and generate a new set)

A = set([2,3,4,5])
B = set([4,5,6,7])
print(A.union(B))

# 输出:{2, 3, 4, 5, 6, 7}
Copy after login

update (take the union and change the original set)

A = set([2,3,4,5])
B = set([4,5,6,7])
A.update(B)
print(A)

# 输出:{2, 3, 4, 5, 6, 7}
Copy after login

Summary

The above is the detailed content of Detailed explanation of set syntax in python3. For more information, please follow other related articles on the PHP Chinese website!

Related labels:
source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template