[Python-Dev] Re: Decimal data type issues

Tim Delaney tcdelaney at optusnet.com.au
Fri Apr 23 09:27:37 EDT 2004

Moore, Paul wrote:

> While I'm sure the numerical properties are iffy, just how bad is
> using binary FP as an intermediate when calculating transcendental
> functions for Decimal values?

Ignoring other issues, what happens when you exceed the limits for float?
Throw an exception, or change to another code path (int/long)? If the
latter, might as well just use it in all cases - makes it more accurate and
less complicated.

> I suspect that this is adequate for "casual" users. And I'm not at all
> sure that the target audience for a Decimal type really cares about
> transcendental functions...

Might be surprised, but there's time to work on it. See next point.

> (I think that boils down to claiming YAGNI, at least in the first
> instance).

Most definitely not going to be in the first instance, as has been stated
before. Python 2.5+ - and then only after a PEP that's gone through as
rigorous a process as this one IMO.

Tim Delaney

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