[boost] Re: Boost Mathematicians

From: Michael Stevens (Michael.Stevens_at_[hidden])
Date: 2004-07-05 11:47:41

Oppps I forgot the last section of David's posting.

On Saturday 03 July 2004 16:54,David Abrahams <dave_at_[hidden]>
> > Other then the many forms of blocking (other then banded) uBLAS supports 
all 
> > these in its design. 
> I believe that a design with really good support for blocking can't be 
> easily grafted onto an existing design that doesn't have it.
Now I understand. Blocking in the context of evaluation rather then sparsity/ 
shape.
Yes this is a good point. Blocking evaluation requires significant 
contribution from the Expression Template mechanism that is not present in 
uBLAS.

> > Other then the lack of ET in the current MTL the big difference
> > between the two libraries is the definition of iterators. Neither
> > design seems to be perfect with regard to efficiency.
> 
> No, and I have some ideas for addressing that.
A improved iterator concept that allows succinct coding and runtime efficiency 
would be a big step forward.

> 
> > Since uBLAS is already in Boost and has a well established and clean user 
> > syntax it would seem strange to ignore it. 
> 
> Yeah, I stopped ignoring it long enough to determine for sure that we
> should probably ignore it :(.
No sure what to say here!
> 
> > For the perspective of building further Linear Algebra algorithms it
> > would not be too hard to use the syntax sufficiently portably so
> > that a future MTL with expression templates could not be used
> > interchangeably.
> 
> We have some problems with the syntax too, as you can see from the
> above.  That said, if the design of MTL makes sparing use of members
> and instead relies on free functions, you should be able to make
> uBlas syntax adapters ;-)
Can't fault the logic here :-)

All the best,
        Michael
-- 
___________________________________
Michael Stevens Systems Engineering
Navigation Systems, Estimation  and
                 Bayesian Filtering
    http://bayesclasses.sf.net
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