set()集合基本操做

運用頻次：☆☆

set是一個無序且不重複元素集，基本操做以下：

1. 建立set集合，會自動轉換成set類型

2. add()：添加元素

 def add(self, *args, **kwargs): # real signature unknown
       # 添加元素
        """
        Add an element to a set.
        
        This has no effect if the element is already present.
        """
        pass

3. clear()：清除元素

 def clear(self, *args, **kwargs): # real signature unknown
        #清除元素
        """ Remove all elements from this set. """
        pass

3. copy()：淺拷貝

def copy(self, *args, **kwargs): # real signature unknown
        """ Return a shallow copy of a set. """
        pass

 4. difference()：取差集，不更新原集合

def difference(self, *args, **kwargs): # real signature unknown
       # 取差集，不更新原集合，從新生成新的集合
        """
        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.)
        """
        pass

 5. difference_update()：取差集，更新原集合

def difference_update(self, *args, **kwargs): # real signature unknown
       # 取差集，更新原集合，不生成新的集合
        """ Remove all elements of another set from this set. """
        pass

 6. discard()：刪除元素，更新原集合

def discard(self, *args, **kwargs): # real signature unknown
       # 刪除指定元素，更新原集合
        """
        Remove an element from a set if it is a member.
        
        If the element is not a member, do nothing.
        """
        pass

 7. intersection()：取交集，返回一個新的集合

def intersection(self, *args, **kwargs): # real signature unknown
       # 取交集，不更新原集合，從新生成新集合
        """
        Return the intersection of two sets as a new set.
        
        (i.e. all elements that are in both sets.)
        """
        pass

 8. intersection_update()：取交集，更新原集合

def intersection_update(self, *args, **kwargs): # real signature unknown
      # 取交集，更新原集合
        """ Update a set with the intersection of itself and another. """
        pass

 9. isdisjoint()：判斷是否有交集，無則返回True

def isdisjoint(self, *args, **kwargs): # real signature unknown
       # 若無交集，則返回True
        """ Return True if two sets have a null intersection. """
        pass

 10. issubset()：判斷是不是子集，是則返回True

def issubset(self, *args, **kwargs): # real signature unknown
       # 判斷另外一集合是否包含該集合，是則返回True
        """ Report whether another set contains this set. """
        pass

 11. issuperset()：判斷是不是父集，是則返回True

def issuperset(self, *args, **kwargs): # real signature unknown
       # 判斷該集合是否包含另外一集合，是則返回True
        """ Report whether this set contains another set. """
        pass

 12. pop()：隨機刪除一個元素並返回，更新原集合

def pop(self, *args, **kwargs): # real signature unknown
       # 隨機刪除一個元素並返回，更新原集合
        """
        Remove and return an arbitrary set element.
        Raises KeyError if the set is empty.
        """
        pass

 13. remove()：刪除元素，更新原集合

 def remove(self, *args, **kwargs): # real signature unknown
       # 刪除指定元素，無返回值，更新原集合
        """
        Remove an element from a set; it must be a member.
        
        If the element is not a member, raise a KeyError.
        """
        pass

 14. symmetric_difference()：取差集，不更新原集合

 def symmetric_difference(self, *args, **kwargs): # real signature unknown
      # 取差集，返回一個新的集合，不更新原集合
        """
        Return the symmetric difference of two sets as a new set.
        
        (i.e. all elements that are in exactly one of the sets.)
        """
        pass

 15. symmetric_difference_update()：取差集，更新原集合

 def symmetric_difference_update(self, *args, **kwargs): # real signature unknown
       # 取差集，更新原集合
        """ Update a set with the symmetric difference of itself and another. """
        pass

 16. union()：取並集，不更新原集合

 def union(self, *args, **kwargs): # real signature unknown
       # 取並集，返回一個新的集合，不更新原集合
        """
        Return the union of sets as a new set.
        
        (i.e. all elements that are in either set.)
        """
        pass

 17. update()：取並集，更新原集合

def update(self, *args, **kwargs): # real signature unknown
      # 取並集，更新原集合
        """ Update a set with the union of itself and others. """
        pass