Re: [boost] [units]

From: Dave Steffen (dgsteffen_at_[hidden])
Date: 2007-03-05 16:01:05

Steven Watanabe writes:
 > AMDG
 > 
 > Dave Steffen <dgsteffen <at> numerica.us> writes:
 > 
 > > 
 > >   a) It might be handy, though, to have (for example) a log function
 > >   that enforces unitless quantities.  For example, 
 > > 
 > >      log ( velocity * time / meters )
 > > 
 > >   is fine, but if you forget to multiply by the time, you get a
 > >   helpful error message.
 > > 
 > >   b) It might also be handy, if possible, to have some functions that
 > >   take units and know what to do; for example, sqrt (m*m) properly
 > >   returns meters, and so forth.
 > > 
 > 
 > Absolutely.
 > 
 > We already have sin/cos &c.
 > 
 > We don't have sqrt but root<2>(m * m) will give
 > give the correct answer (albeit inefficiently). 
 > I'll look through cmath and add all the applicable
 > functions.

 Cool.

 Our application could / should be using this sort of thing, but there
 are some significant difficulties involved.  So we won't be using
 units any time soon, but at some point we'll have to tackle these
 issues.

----------------------------------------------------------------------
Dave Steffen, Ph.D.       Fools ignore complexity.
Software Engineer IV      Pragmatists suffer it.
Numerica Corporation      Some can avoid it.
ph [phone] x227    Geniuses remove it.
dgsteffen_at_[hidden]            -- Alan Perlis