What type is python set?

python set is a data type, a set concept in mathematics, which corresponds to the set type in the Python language. The difference from list and tuple is that set emphasizes a "membership" and has nothing to do with order, so duplicate elements will be eliminated first.

>>> set([1, 1, 1, 1, 2, 3])
set([1, 2, 3])  #重复元素被排除
>>> set([3, 2, 1])
set([1, 2, 3])  #无序的集合
>>>

Creation of set type

Curly braces are used to create set type variables, which is very similar to a dictionary, except that the value is missing. You will gradually find out later that set Types have some similarities with dictionary keys, such as: unordered, non-repeatable, and must be hashable, so it is natural to use curly braces to express them.

The set type also has a standard representation of set([...]). For example,

>>> {'a','b'}
set(['a', 'b'])
>>>

set adds elements

The set type has built-in The function add is used to add elements to set

>>> A = {'a','b'}
>>> A.add('c')
>>> A
set(['a', 'c', 'b'])
>>>

Related recommendations: "Python Tutorial"

The above is the detailed content of What type is python set?. For more information, please follow other related articles on the PHP Chinese website!