zoukankan      html  css  js  c++  java
  • Python---基础---dict_tuple_set

    2019-05-21

    ------------------------

    help(tuple)

    -------------------------

    Help on class tuple in module builtins:

    class tuple(object)
    |  tuple(iterable=(), /)

    |  Built-in immutable sequence.

    |  If no argument is given, the constructor returns an empty tuple.
    |  If iterable is specified the tuple is initialized from iterable's items.

    |  If the argument is a tuple, the return value is the same object.

    |  Methods defined here:

    |  __add__(self, value, /)
    |      Return self+value.

    |  __contains__(self, key, /)
    |      Return key in self.

    |  __eq__(self, value, /)
    |      Return self==value.

    |  __ge__(self, value, /)
    |      Return self>=value.

    |  __getattribute__(self, name, /)
    |      Return getattr(self, name).

    |  __getitem__(self, key, /)
    |      Return self[key].

    |  __getnewargs__(self, /)

    |  __gt__(self, value, /)
    |      Return self>value.

    |  __hash__(self, /)
    |      Return hash(self).

    |  __iter__(self, /)
    |      Implement iter(self).

    |  __le__(self, value, /)
    |      Return self<=value.

    |  __len__(self, /)
    |      Return len(self).

    |  __lt__(self, value, /)
    |      Return self<value.

    |  __mul__(self, value, /)
    |      Return self*value.

    |  __ne__(self, value, /)
    |      Return self!=value.

    |  __repr__(self, /)
    |      Return repr(self).

    |  __rmul__(self, value, /)
    |      Return value*self.

    |  count(self, value, /)
    |      Return number of occurrences of value.

    |  index(self, value, start=0, stop=9223372036854775807, /)
    |      Return first index of value.
    |     
    |      Raises ValueError if the value is not present.

    |  ----------------------------------------------------------------------
    |  Static methods defined here:

    |  __new__(*args, **kwargs) from builtins.type
    |      Create and return a new object.  See help(type) for accurate signature.
    ---------------------------------------------------

    # count() 计算某个元素在元组中出现的次数
    tuple1 = (3,2,4,1,3,6)
    print(tuple1.count(3))

    -----------------------------------------------------

    # index() 获取值在元组中的索引
    tuple1 = (3,2,4,1,3,6)
    print(tuple1.index(3))
    print(tuple1.index(3,1,5))

    ---------------------------------------------------------

     # clear() 清除整个字典   返回None
    dict1 = {'a':1, 'b':2, 'c':3}
    dict2 = dict1.copy()
    print(dict2)

    --------------------------------------------------------

    # fromkeys() 按照指定的序列为键创建字典,值都是一样的
    list1 = ['a', 'b', 'c']
    dict1 = {}.fromkeys(list1)
    dict2 = {}.fromkeys(list1, 3)
    print(dict1,dict2)

    ---------------------------------------------------------

    # get() 根据键获取指定的值    找不到的键如果没有默认值则返回默认值, 如果没默认值,则返回None
    dict1 = {'a':1, 'b':2, 'c':3}
    print(dict1.get('b'))
    print(dict1.get('d'))
    print(dict1.get('d', 4))

    --------------------------------------

    # items() 将字典变成类似于元组的形式方便遍历
    dict1 = {'a':1, 'b':2, 'c':3}
    for k,v in dict1.items():
        print(k,v)
    for i in dict1.items():
        print(i)
       
    print(dict1.items())

    ----------------------------------

     # pop() 移除字典中指定元素  返回键所对应的值,如果键不存在,则返回默认值,如果键找不到,没有默认值,就会报错
    dict1 = {'a':1, 'b':2, 'c':3}
    print(dict1.pop('a'))
    print(dict1)
    print(dict1.pop('d', 4))
    print(dict1.pop('d'))

    ----------------------------------

    # popitem() 移除字典的键值时,返回移除的键和值
    dict1 = {'d':4,'a':1, 'b':2, 'c':3 }
    print(dict1.popitem())

    ------------------------------------

    # update() 修改字典中的值
    dict1 = {'d':4, 'a':1, 'b':2, 'c':3}
    dict1.update({'a':3, 'b':4, 'e':6})
    print(dict1)

    ------------------------------------

    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.

    |  __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.

    |  ----------------------------------------------------------------------
    |  Static methods defined here:

    |  __new__(*args, **kwargs) from builtins.type
    |      Create and return a new object.  See help(type) for accurate signature.

    |  ----------------------------------------------------------------------
    |  Data and other attributes defined here:

    |  __hash__ = None

    ----------------------------------------

    a = set()
    print(a)
    list1 = [1,2,3,4]
    a = set(list1)
    print(a)

    --------------------------------------------

    # add() 向集合中添加元素
    set1 = {5,1,2,3,4,'b','u'}
    set1.add(6)
    print(set1)

    --------------------------------

    # clear()   清空集合
    # copy()   复制集合
    # pop()    随机弹出一个元素
    a = {'a', 'b', 'f', 4}
    a.pop()
    print(a)

    -----------------------------------

    # remove 删除集合中的某个值,如果这个值不在集合中会报错
    a = {'a', 'b', 'f', 4}
    a.remove(4)
    print(a)
    a.remove(4)

    -------------------------------------

    # difference() 差集
    # difference_update() 区别就是第一个返回一个新的集合,第二个把原来集合覆盖
    set1 = {1,2,3,4,7}
    set2 = {2,4,8,111,24}
    set3 = set1.difference(set2)
    print(set3)
    print(set1)

    ------------------------------------------

  • 相关阅读:
    极客时间-左耳听风-程序员攻略-异步I/O模型和Lock-Free编程
    将SSRF升级为RCE(AWS环境)
    PowerShell ISE/文件名解析缺陷远程执行代码漏洞#RCE
    利用工具破解HTTP身份验证的多种方法
    ICMP shell
    CVE-2018-19386:SolarWinds数据库性能分析器中反射的XSS
    Recon ASRC Conference
    Python扫描器-爬虫基础
    The Bug Hunters Methodology v3(ish)
    svn状态图标大全
  • 原文地址:https://www.cnblogs.com/niaocaizhou/p/10898164.html
Copyright © 2011-2022 走看看