---***---传送门---***---
文档解释
def append(self, p_object): """ L.append(object) -> None -- append object to end """ pass def clear(self): """ L.clear() -> None -- remove all items from L """ pass def copy(self): """ L.copy() -> list -- a shallow copy of L """ return [] def count(self, value): """ L.count(value) -> integer -- return number of occurrences of value """ return 0 def extend(self, iterable): """ L.extend(iterable) -> None -- extend list by appending elements from the iterable """ pass def index(self, value, start=None, stop=None): """ 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): """ L.insert(index, object) -- insert object before index """ pass def pop(self, index=None): """ 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): _ """ L.remove(value) -> None -- remove first occurrence of value. Raises ValueError if the value is not present. """ pass def reverse(self): """ L.reverse() -- reverse *IN PLACE* """ pass def sort(self, key=None, reverse=False): """ L.sort(key=None, reverse=False) -> None -- stable sort *IN PLACE* """ pass
[] == [None:None]
切片
+---+---+---+---+---+---+ | P | y | t | h | o | n | +---+---+---+---+---+---+ 0 1 2 3 4 5 -6 -5 -4 -3 -2 -1
li = ['a', 'b', 'c', 'd'] print(li) print(li[1:3]) print(li[:4]) print(li[3:]) print(li[::2]) print(li[1::-1]) # 步长-1表示反向取值, print(li[1:-1])
['a', 'b', 'c', 'd'] ['b', 'c'] ['a', 'b', 'c', 'd'] ['d'] ['a', 'c'] ['b', 'a'] ['b', 'c']
追加 append(在尾部添加)
强行插入 insert (在指定位置添加)
li = ['a', 'b', 'c', 'd'] print(li) li.append('e') print(li) li.insert(1, 'g') print(li)
['a', 'b', 'c', 'd'] ['a', 'b', 'c', 'd', 'e'] ['a', 'g', 'b', 'c', 'd', 'e']
删除(remove, pop, del)
remove() 删除单个元素
li = ['a', 'b', 'c', 'd'] li.remove('a') print(li)
pop() 默认删除最后一个,也可指定引索删除。有返回值!
li = ['a', 'b', 'c', 'd'] b = li.pop(2) print(li) print(b)
['a', 'b', 'd'] c
del
li = ['a', 'b', 'c', 'd'] del li[2] print(li) li = ['a', 'b', 'c', 'd'] del li[:2] print(li)
['a', 'b', 'd'] ['c', 'd']
count 统计指定元素在列表出现的次数
li = ['a', 'a', 'a', 'b', 'c', 'd'] n = li.count('a') print(n)
3