dict字典和set集合
dict
Python内置了字典:dict的支持,dict全称dictionary,在其他语言中也称为map,使用键-值(key-value)存储,具有极快的查找速度。
集合特征:无序且不重复
创建集合
1.set = {1, 2, 3, 4}
2.set2 = set()
3.set3 = set([1, 2, 3, 4])
class
set
(
object
):
"""
set() -> new empty set object
set(iterable) -> new set object
Build an unordered collection of unique elements.
"""
def
add(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Add an element to a set,添加元素
This has no effect if the element is already present.
"""
pass
def
clear(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Remove all elements from this set. 清除内容"""
pass
def
copy(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Return a shallow copy of a set. 浅拷贝 """
pass
def
difference(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Return the difference of two or more sets as a new set. A中存在,B中不存在
(i.e. all elements that are in this set but not the others.)
"""
pass
def
difference_update(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Remove all elements of another set from this set. 从当前集合中删除和B中相同的元素"""
pass
def
discard(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Remove an element from a set if it is a member.
If the element is not a member, do nothing. 移除指定元素,不存在不保错
"""
pass
def
intersection(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Return the intersection of two sets as a new set. 交集
(i.e. all elements that are in both sets.)
"""
pass
def
intersection_update(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Update a set with the intersection of itself and another. 取交集并更更新到A中 """
pass
def
isdisjoint(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Return True if two sets have a null intersection. 如果没有交集,返回True,否则返回False"""
pass
def
issubset(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Report whether another set contains this set. 是否是子序列"""
pass
def
issuperset(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Report whether this set contains another set. 是否是父序列"""
pass
def
pop(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Remove and return an arbitrary set element.
Raises KeyError if the set is empty. 移除元素
"""
pass
def
remove(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Remove an element from a set; it must be a member.
If the element is not a member, raise a KeyError. 移除指定元素,不存在保错
"""
pass
def
symmetric_difference(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Return the symmetric difference of two sets as a new set. 对称差集
(i.e. all elements that are in exactly one of the sets.)
"""
pass
def
symmetric_difference_update(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Update a set with the symmetric difference of itself and another. 对称差集,并更新到a中 """
pass
def
union(
self
,
*
args,
*
*
kwargs):
# real signature unknown
"""
Return the union of sets as a new set. 并集
(i.e. all elements that are in either set.)
"""
pass
def
update(
self
,
*
args,
*
*
kwargs):
# real signature unknown
""" Update a set with the union of itself and others. 更新 """
pass