Old problem with performance

[Simen Kjaeraas]

dsimcha <dsimcha at yahoo.com> wrote:

> I find linear algebra impossible to grok largely because some  
> genius
> mathematician decided to overload a bunch of operators to mean completely
> different things when dealing with matrices than when dealing with  
> scalars.  Heck, the multiplication operator isn't even commutative.

In the schools I've been to (in Norway), multiplication of scalars
has always been indicated by the middle-dot operator (·, U+00B7), as
has componentwise multiplication of matrices. The multiplication
sign (x, ×, U+00D7) was used for cross-product of vectors, as well
as ordinary matrix multiplication. This has given me the impression
(which seems to hold true in the Norwegian school system) that
middle-dot is commutative, multiplication sign is not. I do however
know it does not hold true in all context, which is unfortunate.

--
Simen