Note on python__2021年7月2日Python练习使用list和tuple

Posted 2021-07-21 topia_csdn

list

Python内置的一种数据类型是列表：list。list是一种有序的集合，可以随时添加和删除其中的元素。

tuple

另一种有序列表叫元组：tuple。tuple和list非常类似，但是tuple一旦初始化就不能修改.

list 列表举例

>>> pary = ['apple','bill','chop','delay']
>>> pary
['apple', 'bill', 'chop', 'delay']
>>> pary.append('elf')
>>> pary
['apple', 'bill', 'chop', 'delay', 'elf']
>>>

tuple 元组举例

>>> t = (1,2,3,4,5,6)
>>> t
(1, 2, 3, 4, 5, 6)
>>> t.append('7')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'tuple' object has no attribute 'append'
>>>

list 列表索引

>>> pary
['apple', 'bill', 'chop', 'delay', 'elf']
>>> pary[1]
'bill'
>>> pary(1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'list' object is not callable
>>> pary[-1]
'elf'
>>> len(pary)
5
>>> pary[-5]
'apple'
>>> pary[-6]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: list index out of range
>>> pary[0:2]
['apple', 'bill']
>>> pary[0:4]
['apple', 'bill', 'chop', 'delay']
>>> pary[-1]
'elf'
>>> pary[-1:2]
[]
>>> len(pary[-1:2]
... )
0
>>> len(pary[0:3])
3

tuple 元组列表索引

>>> t=(1,2,3,4,5)
>>> t[1]
2
>>>

错误示例

>>> t=(1,2,3,4,5)
>>> t(1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'tuple' object is not callable

list 列表编辑

 pary
['apple', 'bill', 'chop', 'delay', 'elf', 'flee']
>>> pary
['apple', 'bill', 'chop', 'delay', 'elf', 'flee']
>>> pary.pop(-2)
'elf'
>>> pary
['apple', 'bill', 'chop', 'delay', 'flee']
>>> pary.insert(2,'bottle')
>>> pary
['apple', 'bill', 'bottle', 'chop', 'delay', 'flee']
>>>

错误示例

>>> pary.pop('elf')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'str' object cannot be interpreted as an integer
>>> pary.pop[-1]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'builtin_function_or_method' object is not subscriptable

tuple “编辑”

tuple 元组自身每一个元素的指向不能改变，但是元组内若存在元素自身内容可以改变的可以改变这元素的内容
举例

>>> t = ('a', 'b', ['A', 'B'])
>>> t[2][0] = 'X'
>>> t[2][1] = 'Y'
>>> t
('a', 'b', ['X', 'Y'])

练习

# -*- coding: utf-8 -*-

L = [
    ['Apple', 'Google', 'Microsoft'],
    ['Java', 'Python', 'Ruby', 'php'],
    ['Adam', 'Bart', 'Lisa']
]
# 打印Apple:
print(L[0][0])
# 打印Python:
print(L[1][1])
# 打印Lisa:
print(L[2][2])