Python-List，, 1 切片:取多个元

Python-List，, 1 切片:取多个元

 1 切片:取多个元素 2 >>> names = ["A","B","C","D","E","F"] 3 >>> names[1:4]  #取下标1至下标4之间的数字，包括1，不包括4 4 [‘B‘, C‘, ‘D‘] 5 >>> names[1:-1] #取下标1至-1的值，不包括-1 6 [‘B‘, ‘C‘, ‘D‘, ‘E‘] 7 >>> names[0:3]  8 [‘A‘, ‘B‘, ‘C‘] 9 >>> names[:3] #如果是从头开始取，0可以忽略，跟上句效果一样10 [‘A‘, ‘B‘, ‘C‘]11 >>> names[3:] #如果想取最后一个，必须不能写-1，只能这么写12 [‘D‘, ‘E‘, ‘F‘] 13 >>> names[3:-1] #这样-1就不会被包含了14 [‘D‘, ‘E‘]15 >>> names[0::2] #后面的2是代表，每隔一个元素，就取一个16 [‘A‘, ‘C‘, ‘E‘] 17 >>> names[::2] #和上句效果一样18 [‘A‘, ‘C‘, ‘E‘] 19  20 追加21 >>> names22 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘]23 >>> names.append(‘G‘)  #在最后面插入值24 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘, ‘G‘]25 26 27 插入28 >>> names29 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]30 >>> names.insert(2,‘H‘)  #在C前面插入H31 [‘A‘, ‘B‘, ‘G‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]32 33 修改34 >>> names35 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]36 >>> names[2] = ‘H‘  #把下标2替换掉37 [‘A‘, ‘B‘, ‘H‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]38 39 删除40 >>> names41 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]42 >>> del names[2]  #把下标2删除掉43 [‘A‘, ‘B‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]44 >>> names.remove(‘B‘)  #删除指定元素45 [‘A‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]46 >>> names.pop()  #删除列表最后一个值47 48 扩展49 >>> names150 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]51 >>> names2 = [‘H‘,‘I‘,‘J‘]52 >>> names1.extend(names2)53 >>> names154 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘, ‘H‘, ‘I‘, ‘J‘]55 56 拷贝57 >>> names58 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]59 >>> name_copy = names.copy()60 >>> name_copy61 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘]62 63 统计64 >>> names65 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘, ‘C‘]66 >>> names.count(‘C‘)67 268 69 获取下标70 >>> names71 [‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ , ‘G‘, ‘C‘]72 >>> names.index(‘C‘)73 274 75 排序&翻转76 [‘Alex‘, ‘Amy‘, ‘Amy‘, ‘Tenglan‘, ‘Tom‘, ‘1‘, ‘2‘, ‘3‘]77 >>> names.sort() #python3 里不同数据类型不能放在一起排序了78 >>> names79 [‘1‘, ‘2‘, ‘3‘, ‘Alex‘, ‘Amy‘, ‘Amy‘, ‘Tenglan‘, ‘Tom‘]80 81 >>> names.reverse() #反转82 >>> names83 [‘Tom‘, ‘Tenglan‘, ‘Amy‘, ‘Amy‘, ‘Alex‘, ‘3‘, ‘2‘, ‘1‘]

Python-List