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From: Peter Otten <__peter__@web.de>
Subject: Re: Is there a way to customise math.sqrt(x) for some x?
Date: Sat, 16 Jul 2011 11:37:18 +0200
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:9614

Steven D'Aprano wrote:

> I have a custom object that customises the usual maths functions and
> operators, such as addition, multiplication, math.ceil etc.
> 
> Is there a way to also customise math.sqrt? I don't think there is, but I
> may have missed something.

There seem to be only three methods that can be customized:

$ grep 'LookupSpecial' mathmodule.c
    method = _PyObject_LookupSpecial(number, "__ceil__", &ceil_str);
    method = _PyObject_LookupSpecial(number, "__floor__", &floor_str);
    trunc = _PyObject_LookupSpecial(number, "__trunc__", &trunc_str);