list内置函数

class list(object)
| list(iterable=(), /)
| Built-in mutable sequence.
| If no argument is given, the constructor creates a new empty list.
| The argument must be an iterable if specified.

列表，内置可变序列，如果没有给出可变参数，则创建一个空列表，如果指定了，则这个参数必须是可迭代的。

以下为list内置函数
| append(self, object, /)
| Append object to the end of the list.
在当前列表的后面增加object

>>> a = [1,2,3]
>>> a.append('4')
>>> a
[1, 2, 3, '4']
>>> a.append([1,2,3])
>>> a
[1, 2, 3, '4', [1, 2, 3]]

| clear(self, /)
| Remove all items from list.
清除，将列表内的所有元素都清除

>>> a = [1,2,3]
>>> a.clear()
>>> a
[]

| copy(self, /)
| Return a shallow copy of the list.
复制出一个同样的列表，因为列表使用赋值号时，这两个指针同时指向一块内存，当一个指针修改后，另一个指针也会随着被动修改

>>> a = [1,2,3]
>>> b = a
>>> a.append('1')
>>> a
[1, 2, 3, '1']
>>> b
[1, 2, 3, '1']
>>> c = a.copy()
>>> c
[1, 2, 3, '1']
>>> a.append([1,2,3])
>>> a
[1, 2, 3, '1', [1, 2, 3]]
>>> b
[1, 2, 3, '1', [1, 2, 3]]
>>> c
[1, 2, 3, '1']

| count(self, value, /)
| Return number of occurrences of value.
计算value在列表中出现的次数并返回

>>> a = [1,1,1,1,2,3,4,3,2,22,2,2]
>>> a.count(2)
4
>>> a.count(1)
4

| extend(self, iterable, /)
| Extend list by appending elements from the iterable.

往列表后面延伸一块列表，类似于使用两个列表相加

>>> a.extend([1,2,3])
>>> a
[1, 2, 3, 4, 5, 1, 2, 3]
>>> b = [1,2,3]
>>> a+b
[1, 2, 3, 4, 5, 1, 2, 3, 1, 2, 3]

| index(self, value, start=0, stop=2147483647, /)
| Return first index of value.
| Raises ValueError if the value is not present.

索引，从0到2147483647位开始索引，如果找到了则返回下标，如果没有则报错如果列表长度大于2147483647，则需要重新传入stop值

>>> a = [1,2,3,4]
>>> a.index(2)
1
>>> a.index(5)
Traceback (most recent call last):
  File "<pyshell#37>", line 1, in <module>
    a.index(5)
ValueError: 5 is not in list

| insert(self, index, object, /)
| Insert object before index.
插入，在index位置前方插入一个object，并且如果index超出了列表的长度，并不会报错，只是在列表的最后面加上这个object

>>> a = [1,2,3,4]
>>> a.insert(2,[1,2,3])
>>> a
[1, 2, [1, 2, 3], 3, 4]
>>> a.insert(6,[222,22,2])
>>> a
[1, 2, [1, 2, 3], 3, 4, [222, 22, 2]]
>>> a.insert(100,[00])
>>> a
[1, 2, [1, 2, 3], 3, 4, [222, 22, 2], [0]]
>>> a.append(1)
>>> a
[1, 2, [1, 2, 3], 3, 4, [222, 22, 2], [0], 1]

| pop(self, index=-1, /)
| Remove and return item at index (default last).
| Raises IndexError if list is empty or index is out of range.

删除，默认为删除最后一个元素也可以自己传入一个索引值，并且返回这个元素

>>> a = [1,2,3,4,5]
>>> a.pop()
5
>>> a
[1, 2, 3, 4]
>>> b = a.pop()
>>> b
4
>>> a.pop(2)
3
>>> a
[1, 2]

| remove(self, value, /)
| Remove first occurrence of value.
| Raises ValueError if the value is not present.

移除，从左往右，移除第一次出现value的值，如果不存在则报错

>>> a = [1,2,3,4,3,3,]
>>> a.remove(3)
>>> a
[1, 2, 4, 3, 3]
>>> a.remove(3)
>>> a
[1, 2, 4, 3]
>>> a.remove(5)
Traceback (most recent call last):
  File "<pyshell#59>", line 1, in <module>
    a.remove(5)
ValueError: list.remove(x): x not in list

| reverse(self, /)
| Reverse IN PLACE.
将列表进行反向排序，并没有返回值，因此这里离不能使用复制号

>>> a = [1,2,3,4]
>>> a.reverse()
>>> a
[4, 3, 2, 1]

| *sort(self, /, , key=None, reverse=False)
| Stable sort IN PLACE.
正向排序，如果reverse默认为F，如果为T，则为反向排序

>>> a = [1,2,3,4]
>>> a.sort()
>>> a
[1, 2, 3, 4]
>>> a.sort(reverse=True)
>>> a
[4, 3, 2, 1]

| ----------------------------------------------------------------------
| 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

胖大xian

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python-list内置函数

list内置函数

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