Re: [boost] Quantity library: any interest?

From: Terje Slettebø (tslettebo_at_[hidden])
Date: 2003-04-27 09:01:39

>From: <renej_at_[hidden]>

> we use the int-based template approach for a couple of years now in
> our AGV controller software. We actually sometimes reach the stage that
> it works when succesfully compiled and linked. Since our control software
> is physics throughout (field of robotics), the type safety is very
> important. However, besides the basic SI units we also have 'angle'
> as a dimension which allows us to distinguish 'velocity' and 'angular
> velocity' for example. Hence, from out 'real user' experience (engineering
> point of view) it would be a necessity to add 'angle' as a dimension
> without breaking already defined quantities. Most (all?) units libraries
> already define 'angle' to be dimensionless, which is true in
> scientifically spoken, but pragmatically (engineering ;-) less handy.

There's another question. If we add angle as a dimension, then what kind of
angle is it? There are several kinds of angles, such as radians (plane
angle) and steradians (solid angle). If both were represented by the same
angle dimension, then it probably wouldn't make much sense to add radians
and steradians (and what would be the resulting quantity?), yet, the library
would allow it.

Regards,

Terje