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How to convert a negative number stored as string to a float?

Am getting this error on Python 3.6 and don't know how to get over it.

>>> s = '–1123.04'
>>> float(s)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: could not convert string to float: '–1123.04'
PedroA
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    FWIW, you can use the standard `unicodedata` module to get the name of each char in string that's behaving mysteriously. Eg, if the string is `s` do `import unicodedata as ud` `print(*map(ud.name, s), sep=', ')`. See the module docs for more nifty functions. And of course you can do `print(s.encode('unicode-escape'))` – PM 2Ring Jul 23 '17 at 20:47

2 Answers2

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Your string contains a unicode en-dash, not an ASCII hyphen. You could replace it:

>>> float('–1123.04'.replace('\U00002013', '-'))
-1123.04
BrenBarn
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    You can throw [this](https://pastebin.com/hvm4yDpK) in there if you want to show the difference, if you like. – idjaw Jul 23 '17 at 20:35
  • can you explain how you see the exact unicode type. I have a slightly different dash and was wondering how to fix my issue – qwertylpc Sep 28 '19 at 15:34
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    @qwertylpc: See the comment on the question by Pm 2Ring. You can also use `.encode('unicode-escape')` to get a representation that will use backslash-escape representations for non-ASCII Unicode characters. – BrenBarn Sep 29 '19 at 21:02
2

For a more generic solution, you can use regular expressions (regex) to replace all non-ascii characters with a hyphen. 

import re

s = '–1123.04'

s = re.sub(r'[^\x00-\x7F]+','-', s)

s = float(s)
user2589273
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