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  • python基本数据类型——list

    一、创建列表:

    li = []
    li = list()
    name_list = ['alex', 'seven', 'eric']
    
    name_list = list(['alex', 'seven', 'eric'])

    二、基本操作:

    #append追加
    name_list = ["zhangyanlin","suoning","nick"]
    name_list.append('zhang')
    print(name_list)
     
    #count制定字符出现几次
    name_list = ["zhangyanlin","suoning","nick"]
    name_list.append('zhang')
    name_list.append('zhang')
    name_list.append('zhang')
    print(name_list.count('zhang'))
     
    #extend可扩展,批量往里加数据
    name_list = ["zhangyanlin","suoning","nick"]
    name = ["aylin","zhang","yan","lin"]
    name_list.extend(name)
    print(name_list)
     
    #index找到字符所在的位置
    name_list = ["zhangyanlin","suoning","nick"]
    print(name_list.index('nick'))
     
    #insert插入,往索引里面插入值
    name_list = ["zhangyanlin","suoning","nick"]
    name_list.insert(1,"zhang")
    print(name_list)
     
    #pop在原列表中移除掉最后一个元素,并赋值给另一个变量
    name_list = ["zhangyanlin","suoning","nick"]
    name = name_list.pop()
    print(name)
     
    #remove移除,只移除从左边找到的第一个
    name_list = ["zhangyanlin","suoning","nick"]
    name_list.remove('nick')
    print(name_list)
     
    #reverse反转
    name_list = ["zhangyanlin","suoning","nick"]
    name_list.reverse()
    print(name_list)
     
    #del删除其中元素,删除1到3之间的
    name_list = ["zhangyanlin","suoning","nick"]
    del name_list[1:3]
    print(name_list)

    #join将列表元素用指定字符串连接
    name_list = ["you","are","good"]
    s = " ".join(name_list)
    print(name_list)
    # you are good
    class list(object):
        """
        list() -> new empty list
        list(iterable) -> new list initialized from iterable's items
        """
        def append(self, p_object): # real signature unknown; restored from __doc__
            """ L.append(object) -- append object to end """
            pass
    
        def count(self, value): # real signature unknown; restored from __doc__
            """ L.count(value) -> integer -- return number of occurrences of value """
            return 0
    
        def extend(self, iterable): # real signature unknown; restored from __doc__
            """ L.extend(iterable) -- extend list by appending elements from the iterable """
            pass
    
        def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
            """
            L.index(value, [start, [stop]]) -> integer -- return first index of value.
            Raises ValueError if the value is not present.
            """
            return 0
    
        def insert(self, index, p_object): # real signature unknown; restored from __doc__
            """ L.insert(index, object) -- insert object before index """
            pass
    
        def pop(self, index=None): # real signature unknown; restored from __doc__
            """
            L.pop([index]) -> item -- remove and return item at index (default last).
            Raises IndexError if list is empty or index is out of range.
            """
            pass
    
        def remove(self, value): # real signature unknown; restored from __doc__
            """
            L.remove(value) -- remove first occurrence of value.
            Raises ValueError if the value is not present.
            """
            pass
    
        def reverse(self): # real signature unknown; restored from __doc__
            """ L.reverse() -- reverse *IN PLACE* """
            pass
    
        def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__
            """
            L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;
            cmp(x, y) -> -1, 0, 1
            """
            pass
    
        def __add__(self, y): # real signature unknown; restored from __doc__
            """ x.__add__(y) <==> x+y """
            pass
    
        def __contains__(self, y): # real signature unknown; restored from __doc__
            """ x.__contains__(y) <==> y in x """
            pass
    
        def __delitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__delitem__(y) <==> del x[y] """
            pass
    
        def __delslice__(self, i, j): # real signature unknown; restored from __doc__
            """
            x.__delslice__(i, j) <==> del x[i:j]
                       
                       Use of negative indices is not supported.
            """
            pass
    
        def __eq__(self, y): # real signature unknown; restored from __doc__
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __getattribute__(self, name): # real signature unknown; restored from __doc__
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__getitem__(y) <==> x[y] """
            pass
    
        def __getslice__(self, i, j): # real signature unknown; restored from __doc__
            """
            x.__getslice__(i, j) <==> x[i:j]
                       
                       Use of negative indices is not supported.
            """
            pass
    
        def __ge__(self, y): # real signature unknown; restored from __doc__
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y): # real signature unknown; restored from __doc__
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __iadd__(self, y): # real signature unknown; restored from __doc__
            """ x.__iadd__(y) <==> x+=y """
            pass
    
        def __imul__(self, y): # real signature unknown; restored from __doc__
            """ x.__imul__(y) <==> x*=y """
            pass
    
        def __init__(self, seq=()): # known special case of list.__init__
            """
            list() -> new empty list
            list(iterable) -> new list initialized from iterable's items
            # (copied from class doc)
            """
            pass
    
        def __iter__(self): # real signature unknown; restored from __doc__
            """ x.__iter__() <==> iter(x) """
            pass
    
        def __len__(self): # real signature unknown; restored from __doc__
            """ x.__len__() <==> len(x) """
            pass
    
        def __le__(self, y): # real signature unknown; restored from __doc__
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __lt__(self, y): # real signature unknown; restored from __doc__
            """ x.__lt__(y) <==> x<y """
            pass
    
        def __mul__(self, n): # real signature unknown; restored from __doc__
            """ x.__mul__(n) <==> x*n """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): # real signature unknown; restored from __doc__
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y): # real signature unknown; restored from __doc__
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __repr__(self): # real signature unknown; restored from __doc__
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __reversed__(self): # real signature unknown; restored from __doc__
            """ L.__reversed__() -- return a reverse iterator over the list """
            pass
    
        def __rmul__(self, n): # real signature unknown; restored from __doc__
            """ x.__rmul__(n) <==> n*x """
            pass
    
        def __setitem__(self, i, y): # real signature unknown; restored from __doc__
            """ x.__setitem__(i, y) <==> x[i]=y """
            pass
    
        def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__
            """
            x.__setslice__(i, j, y) <==> x[i:j]=y
                       
                       Use  of negative indices is not supported.
            """
            pass
    
        def __sizeof__(self): # real signature unknown; restored from __doc__
            """ L.__sizeof__() -- size of L in memory, in bytes """
            pass
    
        __hash__ = None
    
    list
    list源码

    三、数据类型转换

    字符串转列表

    s = "你好morra"
    li = list(s)
    print(li)
    
    OUTPUT:
    ['', '', 'm', 'o', 'r', 'r', 'a']

    元组转列表

    tu = ("你好","alex")
    li = list(tu)
    print(li)
    
    OUTPUT:
    ['你好', 'alex']

    字典转列表

    dic = {'k1':'hello','k2':'morra'}
    l3 = list(dic)              #字典在循环的时候默认只循环key
    print(l3)
    
    l4 = list(dic.values())
    print(l4)
    
    l5 = list(dic.items())
    print(l5)
    
    OUTPUT:
    ['k2', 'k1']
    ['morra', 'hello']
    [('k2', 'morra'), ('k1', 'hello')]

    四、可迭代性

    l = ['i', 'am', 'spark']
    # 可以被for循环所迭代
    for i in l:
        print (i)
    # i am spark

    五、可嵌套性

    li = ['字符串',('tuple','hh'),{"key1":"value1","key2":"value2"}]
    print(li[2]["key1"])
    #输出  value1
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  • 原文地址:https://www.cnblogs.com/LiCheng-/p/6431084.html
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