Re: [boost] TR1 Mathematical Special Functions

From: Paul A Bristow (pbristow_at_[hidden])
Date: 2006-08-17 09:07:34

|  -----Original Message-----
|  From: boost-bounces_at_[hidden] 
|  [mailto:boost-bounces_at_[hidden]] On Behalf Of Hubert Holin
|  Sent: 17 August 2006 12:47
|  To: boost_at_[hidden]
|  Subject: Re: [boost] TR1 Mathematical Special Functions
|  
|  John Maddock <john <at> johnmaddock.co.uk> writes:
|  
|  
|  > Joel Eidsath wrote:
|  > > Is there anyone working on adding a boost-license compliant
|  > > implementation of these to boost.TR1? I'm looking at the 
|  possibility
|  > > of doing some work on this as part of a directed study.
|  
|  > Some work: I have a few special function here: 
|  > http://www.johnmaddock.co.uk/toolkit which partly overlap 
|  with TR1, there is 
|  > also a Google SOC project in this area - Xiaogang Zhang 
|  has been working on 
|  > these, just Bessel functions so far, you can browse the 
|  source here: 
|  > https://boost-consulting.com:8443/trac/soc/browser/boost/soc
|  2006/tr1-math/trunk
|  
|  > But any further developments would be welcome 
|  
|  > John.

You might also look at JohAn Rade recent contribution to portable isnan and
signbit:

http://boost-consulting.com/vault/  folder serialisation
non_finite_num_facets.zip

|  In theory, the DLMF project should come to fruition this year
|  (http://dlmf.nist.gov/about/), which can only help both in terms
|  of techniques to use and, one can dream, in interest in the subject.
"
Sadly the last update is "Last Modified Sat, Oct 22, 2005"
|  
|  As far as the TR1 stands, I still feel the lack of 
|  genericity enshrined by
|  the C-style naming conventions of the special functions is a 
|  glaring error.

John Maddock and I have come this conclusion too and in implementing high
math functions, and the statistics functions using them has effectively
abandoned them in favour of a fully templated C++ structure, including
making distributions like normal, student's t, binomial ... a C++ class.

I believe it will still be possible to provide C support - with C-style
named functions, but by packaging C++ to be linkable from C, rather than
vice versa - effectively the TR1 rules.

|  Still, having no standard support for usefull functions is 
|  worse than bad
|  support (that could be built upon), IMHO.
|  
|  So, whatever you can contribute will be most welcome. I 
|  should point out that
|  some requests have been made to have interval computations 

John Maddock is itching to tackle these by using the interval library with
his functions but we are trying to get the math and stats functions out for
pre-veiw first.

|  (as opposed to
|  only pointwise computations), which AFAIK have still gone 
|  completely unanswered,
|  but which do have practical applications;

Strongly agree - we need to know the computational uncertainty - as well as
the measurement uncertainty.

Paul

---
Paul A Bristow
Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB
[phone] & SMS, Mobile [phone] & SMS
pbristow_at_[hidden]