Re: [Boost-users] boost::units - converting from one derived_dimension to another across systems (imperial to metric)

Subject: Re: [Boost-users] boost::units - converting from one derived_dimension to another across systems (imperial to metric)
From: Damien Hocking (damien_at_[hidden])
Date: 2018-11-15 15:29:15

> On Nov 15, 2018, at 8:18 AM, Steven Watanabe via Boost-users <boost-users_at_[hidden]> wrote:
> 
> AMDG
> 
>> On 11/14/2018 05:04 AM, Matt Vinson via Boost-users wrote:
>> I am having trouble converting from one derived_dimension to another across systems (imperial to metric).  I'd like to convert, say, lb/in to, say, kg/m.  I thought I would do the following but get a compiler error #:
> 
> It's not going to work.  lb is a unit of
> force, but kg is a unit of mass.  They are not
> compatible and there is no conversion between
> them.
> 
>> *.h--------------------------------------------------------------------------------
>> namespace dimensional_analysis {
>>     namespace lineal_force {        //lb/in
>>         typedef boost::units::derived_dimension<
>>             boost::units::us::pound_force_base_unit, 1,
>>             boost::units::us::inch_base_unit, -1
>>         >::type lb_per_inch_dimension;
> 
> units are not dimensions.  You can't use
> derived_dimension with base_units.
> 
>>  <snip>
>> 
> 
> In Christ,
> Steven Watanabe
> _______________________________________________
> Boost-users mailing list
> Boost-users_at_[hidden]
> https://lists.boost.org/mailman/listinfo.cgi/boost-users

There is technically a kilogram force unit, kg-f or kilopond.  I don’t know if that’s in Units though.

Damien