[Numpy-discussion] Implementing __format__

Christopher Barker Chris.Barker@noaa....
Mon Nov 15 13:44:12 CST 2010

On 11/15/10 11:35 AM, Pauli Virtanen wrote:
> One can argue that this is a bug in Python or Numpy:
> 	"%d" % numpy.int16(1)
> 	"{0:d}".format(numpy.int16(1))

> To make it work via changes in Numpy: scalars should implement a
> __format__ method. Two choices: either we parse the formatting string
> ourselves, or forward formatting to Python. The PITA in implementing this
> is in parsing the format string.
> Doing formatting ourselves would allow e.g. formatting of long doubles
> properly, which cannot be done via the %-syntax.

Also good handling of NaN, which there is other custom code in numpy to 
handle better than python (in string parsing, anyway).


Christopher Barker, Ph.D.

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