From: Andy Little (andy_at_[hidden])
Date: 2006-06-08 07:44:05


"Martin Bonner" wrote
> ----Original Message----
> From: boost-bounces_at_[hidden]
> [mailto:boost-bounces_at_[hidden]] On Behalf Of Andy Little Sent:
> 08 June 2006 08:32 To: boost_at_[hidden]
> Subject: Re: [boost] [review] pqs
>
>>> "Deane Yang" wrote
>>> Carlo Wood wrote:
>>>> English: meter per second
>>>> Dutch: meter per seconde
>>>> French: mtres par seconde
>>>> German: meter pro sekunde
>>>> Spanish: metro por segundo
>>>>
>>>> I think that 'per' is as much english as 'divided by'.
>>>> People who know english won't be confused by it.
>>>>
>>>
>>> I also vote for "per".
>>
>> in this case, as typedefs for declaring a quantity of a particular
>> type , you
>> end up with
>>
>> velocity:: m_per_s
>> velocity:: mi_per_h
>> acceleration::m_per_s2;
>> reciprocal_time::per_s;
>> reciprocal_mass::per_kg;
>> mass_flow::kg_per_s;
>
> This is *MUCH* easier to read than _div_.
>>
>> It might even be possible to abbreviate it and keep the sense:
>>
>> velocity:: m_p_s
>> velocity:: mi_p_h
>> acceleration::m_p_s2;
>> reciprocal_time::p_s;
>> reciprocal_mass::p_kg;
>> mass_flow::kg_p_s;
>
> But this is not. It gets close to idiomatic forms like mph (but not all
> that close), and is really difficult to read for m/s.
>
>
> Incidentally, none of the above units has a natural "named" unit (with
> the possible exception of reciprocal_time::Hz), so this does actually
> matter.

FWIW pqs has both frequency and reciprocal time. reciprocal time was implemented
so that using an angle value_type would give units of radians per second for
example.

Anyway its clear I havent paid enough attention to the issue of these unit
member typedefs. All ideas welcome.

regards
Andy Little