用for遍历整个列表

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>>> cells =['cellA', 'cellB', 'cellC', 'cellD']
>>> for cel in cells:
... print(cel)
...
cellA
cellB
cellC
cellD

For循环中加入操作

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>>> cells =['cellA', 'cellB', 'cellC', 'cellD']
>>> for cel in cells:
... print('cells list include ' + cel + '.')
...
cells list include cellA.
cells list include cellB.
cells list include cellC.
cells list include cellD.

For循环后加入操作

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>>> cells =['cellA', 'cellB', 'cellC', 'cellD']
>>> for cel in cells:
... print('cells list include ' + cel + '.')
...
>>> print('that is all cells')
cells list include cellA.
cells list include cellB.
cells list include cellC.
cells list include cellD.
that is all cells

For循环在某一范围”使用range()”

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>>> cells = ['cellA', 'cellB', 'cellC', 'cellD']
>>> for i in range(0,3): #实际中 0<=i<3 ... print(cells[i]) ... cellA cellB cellC

range()函数可以指定步长

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>>> cells = ['cellA', 'cellB', 'cellC', 'cellD','cellE','cellF','cellG']
>>> for i in range(0,7,2):
... print(cells[i])
...
cellA
cellC
cellE
cellG

使用range()创建数字列表

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>>> numbers = list(range(1,6))
>>> print(numbers)
[1, 2, 3, 4, 5]

range()函数可以指定步长

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>>> numbers = list(range(1,6,2))
>>> print(numbers)
[1, 3, 5]
>>>

数字列表的简单计算

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>>> digitals = list(range(1,10))
>>> print(digitals)
[1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> min(digitals)
1
>>> max(digitals)
9
>>> sum(digitals)
45

列表切片

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>>> cells = ['cellA', 'cellB', 'cellC', 'cellD','cellE','cellF','cellG']
>>> print(cells[0:4]) #第一个至第3个
['cellA', 'cellB', 'cellC', 'cellD']
>>> print(cells[:4]) #第一个至第3个
['cellA', 'cellB', 'cellC', 'cellD']
>>> print(cells[2:]) #第3个至最后一个
['cellC', 'cellD', 'cellE', 'cellF', 'cellG']
>>> print(cells[-2:]) #倒数第2个至最后一个
['cellF', 'cellG']

遍历切片

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>>> cells = ['cellA', 'cellB', 'cellC', 'cellD','cellE','cellF','cellG']
>>> for cel in cells[:4]:
... print(cel)
...
cellA
cellB
cellC
cellD

复制列表

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>>> cells = ['cellA', 'cellB', 'cellC', 'cellD','cellE','cellF','cellG']
>>> another = cells[:]
>>> print(another)
['cellA', 'cellB', 'cellC', 'cellD', 'cellE', 'cellF', 'cellG']

定义元组

元组用圆括号表示，其元素不可更改，但可以重新定义，可以用索引访问。

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>>> dimenssions = (200, 300)
>>> print(dimensions[0])
200
>>> print(dimensions[1])
300

遍历元组

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>>> dimensions = (200, 300)
>>> for dim in dimensions:
... print(dim)
...
200
300

修改元组变量

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>>> dimensions = (200, 300)
>>> for dim in dimensions:
... print(dim)
...
200
300

重新定义元组

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>>> dimensions = (400, 500)
>>> for dim in dimensions:
... print(dim)
...
400
500