27 lines
617 B
Markdown
27 lines
617 B
Markdown
---
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title: Reverse number
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tags: math
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cover: taking-photos
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firstSeen: 2020-10-04T14:21:41+03:00
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lastUpdated: 2020-11-02T19:28:27+02:00
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---
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Reverses a number.
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- Use `str()` to convert the number to a string, slice notation to reverse it and `str.replace()` to remove the sign.
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- Use `float()` to convert the result to a number and `math.copysign()` to copy the original sign.
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```py
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from math import copysign
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def reverse_number(n):
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return copysign(float(str(n)[::-1].replace('-', '')), n)
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```
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```py
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reverse_number(981) # 189
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reverse_number(-500) # -5
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reverse_number(73.6) # 6.37
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reverse_number(-5.23) # -32.5
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```
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