From: Paul A. Bristow (boost_at_[hidden])
Date: 2001-11-01 13:05:16
> -----Original Message-----
> From: Ed Brey [mailto:edbrey_at_[hidden]]
> Sent: Tuesday, October 30, 2001 6:18 PM
> To: boost_at_[hidden]
> Subject: Re: [boost] Math constants: Inclusion requirements
> From: "Paul A. Bristow" <boost_at_[hidden]>
> > In general I agree with this, however the whole point is to ensure
> > that NO compilers don't make any difference to the calculated value,
> > so NO compiler is suitable as a benchmark - these values ARE
> the benchmark!
> Cleaning up for compilers with poor QoI goes beyond the charter I
> had in mind of the constants library. Rather, I think the
> central thrust of the library should be to complement good
> compilers by providing users the basic tools they need to write
> math-based code productively.
Agreed - but you have clearly not met the 'computer validation' requirements
which have infested highly regulated industries such as food and
Having a single definition IS important because it deters
the validators, generally not very knowledgeable,
from worrying about about compiler QoI.
two_pi is just as much a constant as pi.
Once two_pi is calculated, there is an end to it.
(And most use of pi (apart from area) is probably two_pi rather than pi!)
Dr Paul A Bristow, hetp Chromatography
LA8 8AB UK
+44 1539 561830
Mobile +44 7714 33 02 04
Boost list run by bdawes at acm.org, gregod at cs.rpi.edu, cpdaniel at pacbell.net, john at johnmaddock.co.uk