集合

set

创建空集合  a=set()

转化一个数据为集合:set(obj),  注意数字不能直接转化成集合,其他都可以,只要是可迭代类型

set(一个字典),则集合内元素为字典的键值:

关键是集合内置了去重,交集,并集,差集,对称差集函数,这是别的数据类型没有的

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 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,所有差集,A中有B中没有+B中有A中没
         
  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
 
实例:
  

 

posted @ 2018-12-10 20:45  吉元吉  阅读(118)  评论(0编辑  收藏  举报