Re: [boost] Re: Re: Dimensional Analysis

From: Aleksey Gurtovoy (agurtovoy_at_[hidden])
Date: 2005-02-01 23:52:13

Matt Austern writes:
> There's actually something even lower level than a dimension library. 
> In essence, what we've got is:
>  - We're generalizing the notion of an arithmetic type T to a type of
> the form <T,X>, where X is some sort of tag.
>  - For any X1 and X2 and any arithmetic operation 'op', we have rules
> for whether <T,X1> op <T,X2> is well defined.  If it is then the
> result is tagged as <T,X3>, and we have rules to determine X3 in terms
> of X1, X2, and op.

That's basically what we have here at Meta. Low-profile, but extremely
useful. FWIW, ours is spelled as 'scalar_type<T,X>'.

>
> All of the knowledge about how to represent dimensional systems (mpl
> vectors, compile-time fractions, etc.) is higher level than this.

Yep.

-- 
Aleksey Gurtovoy
MetaCommunications Engineering