pythonunicodetranslation

Python: How can I replace full-width characters with half-width characters?


If this was PHP, I would probably do something like this:

function no_more_half_widths($string){
  $foo = array('1','2','3','4','5','6','7','8','9','10')
  $bar = array('1','2','3','4','5','6','7','8','9','10')
  return str_replace($foo, $bar, $string)
}

I have tried the .translate function in python and it indicates that the arrays are not of the same size. I assume this is due to the fact that the individual characters are encoded in utf-8. Any suggestions?


Solution

  • The built-in unicodedata module can do it:

    >>> import unicodedata
    >>> foo = u'1234567890'
    >>> unicodedata.normalize('NFKC', foo)
    u'1234567890'
    

    The “NFKC” stands for “Normalization Form KC [Compatibility Decomposition, followed by Canonical Composition]”, and replaces full-width characters by half-width ones, which are Unicode equivalent.

    Note that it also normalizes all sorts of other things at the same time, like separate accent marks and Roman numeral symbols.