Boost logo

Boost :

Subject: Re: [boost] Preliminary submission: generic linear algebra algorithms library Boost LA
From: Emil Dotchevski (emildotchevski_at_[hidden])
Date: 2009-10-20 13:26:42


On Tue, Oct 20, 2009 at 2:41 AM, Thomas Klimpel
<Thomas.Klimpel_at_[hidden]> wrote:
> The final piece to fully confuse me are the files "matrix_determinant.hpp"
> and "matrix_inverse.hpp".

They are part of the library interface, not examples.

> But in this case, I wonder why you used an algorithm of complexity O(n!)
> for computing the determinant, when it's easy to implement an algorithm of
> complexity O(n^3) for computing the determinant. (The complexity of
> O(n^2*!(n-1)) for computing the inverse is also not better.)

You are correct that the current implementations are not very
efficient for large size matrices, where "large" is perhaps as small
as 5x5 for some values of "very". :)

(However the overloads that kick in automatically for 2x2, 3x3 and 4x4
matrices are efficient.)

> I doubt that you would propose a totally inefficient library for review.

My efforts have been focused on getting the interface correct, and on
decoupling algorithms from data types. There is more work to be done.

Emil Dotchevski
Reverge Studios, Inc.
http://www.revergestudios.com/reblog/index.php?n=ReCode


Boost list run by bdawes at acm.org, gregod at cs.rpi.edu, cpdaniel at pacbell.net, john at johnmaddock.co.uk