Re: [Boost-users] [Units] Un-scaling dimensionless value

Subject: Re: [Boost-users] [Units] Un-scaling dimensionless value
From: Gavin Lambert (gavinl_at_[hidden])
Date: 2014-02-18 00:57:34

On 18/02/2014 11:14, Quoth Lindley French:
>>     Bear in mind that scaling is used not just for SI prefixes but also
>>     for lb/kg conversions and similar.  Double is probably the only way
>>     to go there.
>
> Yes, I caught that subtlety and I understand it in that context. I just
> feel there should be some way to use Boost.Units---portions of it,
> anyway---in a context where exact math is required and floating point is
> therefore forbidden.

I don't disagree (and it might theoretically be possible, when the units 
involved only use rational scaling and not actual floating-point 
conversion factors, and when scaling is not too large).

But I think the current implementation is fairly tightly wedded to 
floating point internally, and it might be tricky to break that link.