Python列表 |流行音乐()
Python list pop()是Python中的一个内置函数,它从 List 或给定的索引值中删除并返回最后一个值。
Syntax:
list_name.pop(index)
Parameter:
- index (optional) – The value at index is popped out and removed. If the index is not given, then the last element is popped out and removed.
Returns: The last value or the given index value from the list.
Exception: When the index is out of range, it returns IndexError.
示例 1:使用 pop() 方法
Python3
# Python3 program for pop() method
list1 = [ 1, 2, 3, 4, 5, 6 ]
# Pops and removes the last element from the list
print(list1.pop())
# Print list after removing last element
print("New List after pop : ", list1, "\n")
list2 = [1, 2, 3, ('cat', 'bat'), 4]
# Pop last three element
print(list2.pop())
print(list2.pop())
print(list2.pop())
# Print list
print("New List after pop : ", list2, "\n")
Python3
# Python3 program showing pop() method
# and remaining list after each pop
list1 = [ 1, 2, 3, 4, 5, 6 ]
# Pops and removes the last
# element from the list
print(list1.pop(), list1)
# Pops and removes the 0th index
# element from the list
print(list1.pop(0), list1)
Python3
# Python3 program for error in pop() method
list1 = [ 1, 2, 3, 4, 5, 6 ]
print(list1.pop(8))
Python3
# Python3 program demonstrating
# practical use of list pop()
fruit = [['Orange','Fruit'],['Banana','Fruit'], ['Mango', 'Fruit']]
consume = ['Juice', 'Eat']
possible = []
# Iterating item in list fruit
for item in fruit :
# Inerating use in list consume
for use in consume :
item.append(use)
possible.append(item[:])
item.pop(-1)
print(possible)
输出:
6
New List after pop : [1, 2, 3, 4, 5]
4
('cat', 'bat')
3
New List after pop : [1, 2]
示例 2
Python3
# Python3 program showing pop() method
# and remaining list after each pop
list1 = [ 1, 2, 3, 4, 5, 6 ]
# Pops and removes the last
# element from the list
print(list1.pop(), list1)
# Pops and removes the 0th index
# element from the list
print(list1.pop(0), list1)
输出:
6 [1, 2, 3, 4, 5]
1 [2, 3, 4, 5]
示例 3:演示 索引错误
Python3
# Python3 program for error in pop() method
list1 = [ 1, 2, 3, 4, 5, 6 ]
print(list1.pop(8))
输出:
Traceback (most recent call last):
File "/home/1875538d94d5aecde6edea47b57a2212.py", line 5, in
print(list1.pop(8))
IndexError: pop index out of range
示例 4:实际示例
水果列表包含fruit_name和表示其水果的属性。另一个清单消费有两个项目果汁和吃。在 pop() 和 append() 的帮助下,我们可以做一些有趣的事情。
Python3
# Python3 program demonstrating
# practical use of list pop()
fruit = [['Orange','Fruit'],['Banana','Fruit'], ['Mango', 'Fruit']]
consume = ['Juice', 'Eat']
possible = []
# Iterating item in list fruit
for item in fruit :
# Inerating use in list consume
for use in consume :
item.append(use)
possible.append(item[:])
item.pop(-1)
print(possible)
输出:
[['Orange', 'Fruit', 'Juice'], ['Orange', 'Fruit', 'Eat'],
['Banana', 'Fruit', 'Juice'], ['Banana', 'Fruit', 'Eat'],
['Mango', 'Fruit', 'Juice'], ['Mango', 'Fruit', 'Eat']]