Re: [boost] boost.numeric (was Re: Re: matrix library?)

From: Jeremy Siek (jsiek_at_[hidden])
Date: 2001-03-28 00:06:23

Hi Joerg,

I've taken a quick look at your matrix library. You and Mathias have done
a nice job!

I have some trivial differences of opinion about parts of the interface,
but much of the design looks right. Since this is a prototype, I won't
comment on too many implementation details, though one particular gotcha
caught my attention: at least some of the iterators were not std
conformant. Perhaps using the iterator_adaptor library would provide an
easy route to providing complete iterators.

Getting back to the interface, some things that bothered me:

The functions whose names end in "1" or "2" like size1(), size2(), and
begin1(), begin2(). This naming scheme was not intuitive to me. 

Also, your matrix class almost has a container-of-container interface, but
not quite. Why not go all the way?

Hmmm, brainstorming with Ron here. I'm wondering if the
dense-matrix-as-a-data-structure interface should just be the exact same
interface as a 2-D multi_array... the only difference would be that the
matrix class would inherit from matrix_expression so that it would have
all the basic linear algebra operations (thereby fullfilling the
matrix-in-a-linear-algebra interface). Similarly for vector.

Did you provide only left scalar multiplication on purpose, or
where you planing on adding right mult as well?

Have you had any thoughts about how things would extend to sparse
matrices?

Cheers,
Jeremy

On Tue, 27 Mar 2001 walter_at_[hidden] wrote:
walter> ... in the meantime we would like to contribute the current version 
walter> of our matrix library
walter> to get the discussion somewhat more concrete.
walter>  
walter> What we have done so far:
walter>  
walter> - BLAS-compatible functionality
walter> - support for expression templates
walter> - iterator concept
walter> - developed on MSVC, casually tested with Borland C and GNU C
walter> 
walter> You may find the library for download in the boost files section.
walter>  
walter> Best regards
walter>  
walter> Joerg Walter

----------------------------------------------------------------------
 Jeremy Siek                        www: http://www.lsc.nd.edu/~jsiek/
 Ph.D. Candidate                  email: jsiek_at_[hidden]
 Univ. of Notre Dame         work phone: [phone]
----------------------------------------------------------------------