Re: [boost] Re: Re: Re: Dimensional Analysis

From: Terje Slettebø (tslettebo_at_[hidden])
Date: 2005-01-30 13:52:09

>From: "Robert Ramey" <ramey_at_[hidden]>

> Andy Little wrote:
> > I would hope that a general purpose physical quantities lib would
> > deal with units, even if you dont use anything but the base units.
> > The Mars lander crash and all that. IOW you need to be explicit about
> > what units you are using.
>
> In my view, a dimension library has to exist independently of any units
> library.  It is a separate and smaller concept.  I should stand on its
own.

At the risk of sounding stupid: What's a dimension library? I.e. how might
it look like, and be used (preferably a code example)? I've searched the
Boost list for "dimension library"/"dimensions library", but your posting is
the only one coming up.

For example, if it only takes care of dimensional analysis (i.e. dimension
calculations), how many dimensions should it have, if it's independent of
units? If the answer is "user-configurable through typelists/vectors", have
anyone done any compile-time timing of dimension calulation-heavy code using
this approach, compared to a fixed set of dimensions? Won't this bring us
right back to the "how many dimensions"-discussion of a unit/quantity
library?

Regards,

Terje