好的,所以我现在有Python代码,它做了这样的事情:
if plug in range(1, 5):
print "The number spider has disappeared down the plughole"
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但我真正想要做的是检查的数量并不在范围内.我用Google搜索并查看了Python文档但我找不到任何内容.有任何想法吗?
附加数据:运行此代码时:
if not plug in range(1, 5):
print "The number spider has disappeared down the plughole"
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我收到以下错误:
Traceback (most recent call last):
File "python", line 33, in <module>
IndexError: list assignment index out of range
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我也尝试过:
if plug not in range(1,5):
print "The number spider has disappeared down the plughole"
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哪个返回了相同的错误.
Mar*_*nen 18
如果您的范围step是1,那么使用它的性能要快得多:
if not 1 <= plug < 5:
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比使用not他人建议的方法更好:
if plug not in range(1, 5)
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证明:
>>> import timeit
>>> timeit.timeit('1 <= plug < 5', setup='plug=3') # plug in range
0.053391717400628654
>>> timeit.timeit('1 <= plug < 5', setup='plug=12') # plug not in range
0.05137874743129345
>>> timeit.timeit('plug not in r', setup='plug=3; r=range(1, 5)') # plug in range
0.11037584743321105
>>> timeit.timeit('plug not in r', setup='plug=12; r=range(1, 5)') # plug not in range
0.05579263413291358
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这甚至没有考虑到创建时间所花费的时间range.
这似乎也有效:
if not 2 < 3 < 4:
print('3 is not between 2 and 4') # which it is, and you will not see this
if not 2 < 10 < 4:
print('10 is not between 2 and 4')
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我想,原始问题的确切答案是if not 1 <= plug < 5:。