And by the same logic you should always check for
the identity matrix, since the checking is O(n^2).



----- Original Message -----
From: "Mark D. Niemiec" <[EMAIL PROTECTED]>
Date: Saturday, September 2, 2006 11:39 am
Subject: [Jprogramming] Re: Symmetric inner and outer products

> Since inner product is an O(n^3) process, and checking to see if a 
> matrix is O(n^2),
> if special code were implemented to handle symmetrical matrices, 
> wouldn't it just
> be easier to always check each time, since the additional cost 
> would be insignificant?
> 
> The same logic could also apply to other symmetric matrix 
> operations that could be
> significantly improved by special code. In particular,  128!:1 
> could be replaced by %.
> which could just automatically invoke the special code for upper 
> tridiagonal matrices
> after just checking for zero, since the cost of the check is much 
> smaller than the cost
> of the inversion.


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