[C++-sig] buildin converter for long double

[jiangzuoyan at gmail.com]

how about return a wrap type of long double to cheating boost/python, and
register youself converter as

  PyObject * o = PyArrayScalar_New(LongDouble);
  PyLongDoubleScalarObject * s = (PyLongDoubleScalarObject*)o;
  s->obval = value;

Don't forget to call import_array() in your model init function.

BTW, I think float128 is not useful, it's slow. and in most case, change
algorithm to avoid precision problem is another *better* approach.


                                                      Changsheng Jiang


On Mon, Nov 5, 2012 at 6:27 PM, Holger Brandsmeier <brandsmeier at gmx.de>wrote:

> Dear list,
>
> the boost python buildin converter for long double:
>   BOOST_PYTHON_TO_PYTHON_BY_VALUE(long double,
> ::PyFloat_FromDouble(x), &PyFloat_Type)
>   converter/builtin_converters.hpp
> identifies long double, which on my system is a 128bit float, with a
> 64bit float in python. I would like to identify it with numpy`s
> float128. Can you give me any hings how I would be able to do that?
>
> -Holger
> _______________________________________________
> Cplusplus-sig mailing list
> Cplusplus-sig at python.org
> http://mail.python.org/mailman/listinfo/cplusplus-sig
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/cplusplus-sig/attachments/20121106/eecc3abe/attachment.html>