56 lines
1.2 KiB
Markdown
56 lines
1.2 KiB
Markdown
# Python 范围函数
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> 原文：<https://www.pythonforbeginners.com/modules-in-python/python-range-function>
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## 范围函数
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Python 中内置的 range 函数对于生成列表形式的
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数字序列非常有用。
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给定的端点决不是生成列表的一部分；
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range(10)生成 10 个值的列表，长度为 10 的
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序列的合法索引。
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可以让范围从另一个数字开始，或者指定一个
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不同的增量(甚至是负数；
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有时这被称为“步骤”):
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## 产品系列示例
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```py
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>>> range(1,10)
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[1, 2, 3, 4, 5, 6, 7, 8, 9]
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# You can use range() wherever you would use a list.
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a = range(1, 10)
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for i in a:
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print i
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for a in range(21,-1,-2):
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print a,
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#output>> 21 19 17 15 13 11 9 7 5 3 1
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# We can use any size of step (here 2)
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>>> range(0,20,2)
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[0, 2, 4, 6, 8, 10, 12, 14, 16, 18]
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>>> range(20,0,-2)
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[20, 18, 16, 14, 12, 10, 8, 6, 4, 2]
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# The sequence will start at 0 by default.
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#If we only give one number for a range this replaces the end of range value.
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>>> range(10)
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[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
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# If we give floats these will first be reduced to integers.
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>>> range(-3.5,9.8)
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[-3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8]
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```
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##### 更多阅读
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[http://www.python.org](https://www.python.org "python_org") |