Search code examples
pythonpython-3.5

Convert a number using atof

In Python 3.5, I'd like to convert a German number string to a float using locale.atof with the following code:

import locale
from locale import atof
locale.setlocale(locale.LC_ALL, 'de_DE')

number = atof('17.907,08')

However, this raises a ValueError:

ValueError: could not convert string to float: '17.907.08'

Why? Isn't this exactly what atof() was made for?

Solution

  • You can't have more than one dot (.) or comma (,) in your number since both of these symbols are used by atof() to separate the decimal part of your number from its integer part.

    Since the dots are not needed for Python to correctly represent your number, you should remove them and only keep the comma:

    import locale
from locale import atof
locale.setlocale(locale.LC_ALL, 'de_DE')

string_nb = '17.907,08'
string_nb = string_nb.replace('.', '')
number = atof(string)