參考連結： Python set集合 intersection()
集合(set)
python的資料結構的另一種表現形式。作用：自動清除集合類型中的元素重複資料(set),以及元素排序。集合類型的元素排序是無序不重複。
快速通路集合(set)
set1=set([1,2,3,4])
set2=set(['A','B','D','C'])
set3=set(['A','C', 'B', 'D'])
set4=set(['A','B','D','C','B'])
set5=set('E')
#set6=set('E','A')
#錯誤提示TypeError: set expected at most 1 arguments, got 2------是以set6不合理
set7=set('hello')
set8=set(['A','B','D','C','B'])
print('1.',set1)
print('2.',set2)
print('3.',set3)
print('4.',set4)
print('5.',set5)
print('6.',set7)
print('7.',set8)
print('8.',id(set1))
print('9.',id(set2))
print('10.',id(set3))
print('11.',id(set4))
print('12.',id(set5))
print('13.',id(set7))
print('14.',id(set8))
#輸出1. {1, 2, 3, 4}
2. {'A', 'C', 'B', 'D'}
3. {'A', 'C', 'B', 'D'}
4. {'A', 'C', 'B', 'D'}
5. {'E'}
6. {'h', 'e', 'l', 'o'}
7. {'A', 'C', 'B', 'D'}
8. 1462456352552
9. 1462470585032
10. 1462470585704
11. 1462456352328
12. 1462470586152
13. 1462470585928
14. 1462470585480
涉及修改集合資料的相關函數以及運算符—程式說明
set9=set([1,2,3,4,5,6,7])
set20=set([1,2,3,5,8,4,7])
set11=set9
set12=set9
#set13=set9
set14=set9
set15=set9
set16=set9
#set17=set9
set18=set9
set19=set9
#set22=set9
print('18.',set9)
print('19.',set20)
#輸出 18. {1, 2, 3, 4, 5, 6, 7}
19. {1, 2, 3, 4, 5, 7, 8}
set9.add(8)
print('1.',set9)
#輸出 1. {1, 2, 3, 4, 5, 6, 7, 8}
#.add 集合類型添加元素
set21=set20.copy()
print('13.',id(set20))
print('14.',id(set21))
print('15.',set21)
print('16.',set20)
#輸出 13. 1462470584360
14. 1462472086472
15. {1, 2, 3, 4, 5, 7, 8}
16. {1, 2, 3, 4, 5, 7, 8}
#.copy 集合類型元素複制
set9.discard(2)
set11.discard(99)
print('3.',set9)
print('4.',set11)
#輸出 3. {1, 3, 4, 5, 6, 7, 8}
4. {1, 3, 4, 5, 6, 7, 8}
#.discard 删除集合類型中指定元素，如果指定元素不存在不會報錯
set12.pop()
#set13.pop(1)
#錯誤提示STypeError: pop() takes no arguments (1 given)------是以set13不合理
print('5.',set12)
#print('6.',set13)
#輸出 5. {3, 4, 5, 6, 7, 8}
#.pop 随機删除集合類型中元素
set14.remove(7)
set15.remove(99)
#輸出 KeyError: 99(出現報錯）
print('7.',set14)
print('8.',set15)
#輸出 7. {3, 4, 5, 6, 8}
#.remove 删除集合類型中指定元素，如果指定元素不存在會報錯,并終止程式
set16.update([88,99])
#set17.update([88,99，77])
#錯誤提示SyntaxError: invalid character in identifier------是以set17不合理
set18.update([88])
print('9.',set16)
#print('10.',set17)
print('11.',set18)
#輸出 9. {3, 4, 5, 6, 99, 8, 88}
11. {3, 4, 5, 6, 99, 8, 88}
#.update 更新集合類型的元素
set19.clear()
#del set22()
#錯誤提示SyntaxError: can't delete function call------是以set22不合理
print('12.',set19)
#print('17.',set22)
#輸出 12. set()
#.claer 清空集合類型的元素
.del set() 清空集合
print('20.',set9.issubset(set20))
print('21.',set9<=set20)
#輸出 21. False
#輸出 20. False
#setA.issubset(setB) 運算符： setA<=setB 檢測setA中的每一個元素是否都在setB中，子集(setB是否是setA的子集)
print('22.',set9.issuperset(set20))
#輸出 22. False
#setA.issuperset(setB) 運算符： setA>=setB 檢測setB中的每一個元素是否都在setA中，父集(setB是否是setA的父集)
print('23.',set9.union(set20))
#輸出 23. {1, 2, 3, 4, 5, 6, 7, 8}
#setA.union(setB) 運算符： setA\setB 創造一個新的集合，元素包含setB和setA所有元素，并集(所有元素：setB+setA)
print('24.',set9.intersection(set20))
#輸出 24. {1, 2, 3, 4, 5, 7}
#setA.intersection(setB) 運算符： setA&setB 檢創造一個新的集合，元素包含setB和setA共同元素，交集(共同元素：setB+setA)
print('25.',set20.difference(set9))
#輸出 25. {8}
#setB.difference(setA) 運算符： setB-setA 檢創造一個新的集合，元素包含setB和setA集合元素中，隻setB所擁有的元素，差集(差異元素：setB-setA)
print('26.',set9.symmetric_difference(set20))
#輸出 26. {6, 8}
#setA.symmetric_difference(setB) 運算符： setA^setB 檢創造一個新的集合，元素包含setB和setA集合元素中，不重複的元素，對稱差集(差異元素：setA^setB)
集合(set)幫助文檔
print(help(set))
Help on class set in module builtins:
class set(object)
| set() -> new empty set object
| set(iterable) -> new set object
|
| Build an unordered collection of unique elements.
|
| Methods defined here:
|
| __and__(self, value, /)
| Return self&value.
|
| __contains__(...)
| x.__contains__(y) <==> y in x.
|
| __eq__(self, value, /)
| Return self==value.
|
| __ge__(self, value, /)
| Return self>=value.
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __gt__(self, value, /)
| Return self>value.
|
| __iand__(self, value, /)
| Return self&=value.
|
| __init__(self, /, *args, **kwargs)
| Initialize self. See help(type(self)) for accurate signature.
|
| __ior__(self, value, /)
| Return self|=value.
|
| __isub__(self, value, /)
| Return self-=value.
|
| __iter__(self, /)
| Implement iter(self).
|
| __ixor__(self, value, /)
| Return self^=value.
|
| __le__(self, value, /)
| Return self<=value.
|
| __len__(self, /)
| Return len(self).
|
| __lt__(self, value, /)
| Return self<value.
|
| __ne__(self, value, /)
| Return self!=value.
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.
|
| __or__(self, value, /)
| Return self|value.
|
| __rand__(self, value, /)
| Return value&self.
|
| __reduce__(...)
| Return state information for pickling.
|
| __repr__(self, /)
| Return repr(self).
|
| __ror__(self, value, /)
| Return value|self.
|
| __rsub__(self, value, /)
| Return value-self.
|
| __rxor__(self, value, /)
| Return value^self.
|
| __sizeof__(...)
| S.__sizeof__() -> size of S in memory, in bytes
|
| __sub__(self, value, /)
| Return self-value.
|
| __xor__(self, value, /)
| Return self^value.
|
| add(...)
| Add an element to a set.
|
| This has no effect if the element is already present.
|
| clear(...)
| Remove all elements from this set.
|
| copy(...)
| Return a shallow copy of a set.
|
| difference(...)
| Return the difference of two or more sets as a new set.
|
| (i.e. all elements that are in this set but not the others.)
|
| difference_update(...)
| Remove all elements of another set from this set.
|
| discard(...)
| Remove an element from a set if it is a member.
|
| If the element is not a member, do nothing.
|
| intersection(...)
| Return the intersection of two sets as a new set.
|
| (i.e. all elements that are in both sets.)
|
| intersection_update(...)
| Update a set with the intersection of itself and another.
|
| isdisjoint(...)
| Return True if two sets have a null intersection.
|
| issubset(...)
| Report whether another set contains this set.
|
| issuperset(...)
| Report whether this set contains another set.
|
| pop(...)
| Remove and return an arbitrary set element.
| Raises KeyError if the set is empty.
|
| remove(...)
| Remove an element from a set; it must be a member.
|
| If the element is not a member, raise a KeyError.
|
| symmetric_difference(...)
| Return the symmetric difference of two sets as a new set.
|
| (i.e. all elements that are in exactly one of the sets.)
|
| symmetric_difference_update(...)
| Update a set with the symmetric difference of itself and another.
|
| union(...)
| Return the union of sets as a new set.
|
| (i.e. all elements that are in either set.)
|
| update(...)
| Update a set with the union of itself and others.
|
| ----------------------------------------------------------------------
| Data and other attributes defined here:
|
| __hash__ = None