Re: [Lapackpp-devel] norm() function in matricies?

[Christian S. <sti...@tu...>]

Am Freitag, 13. August 2004 20:58 schrieb Jacob \(Jack\) Gryn:
> Is there a function that calculates the norm of a matrix?  Maybe we should
> implement it?

In blas1++.h, there are several norms for vectors. In blas++.h, there is 
Norm_Inf for most matrices. Norm2 should probably be added, too, somewhere. 
Funny that I didn't need it so far...

> How about pointwise operators?  i.e. a pointwise division..

You mean element-wise? Is there a lapack (blas) procedure for that? Probably 
not. (Seems to me that this operation is not needed for numerics.) Anyway, 
yes, you can implement this somewhere as an auxiliary function.

> I also have an unrelated question.  Can operator's be created for any ascii
> character/string, or they are limited to the same operators already used by
> C++?
>
> For example, if I wanted to make a pointwise multiplier, could I do
> operator.*=  (note the dot before the asterisk)

I don't think that's possible. On the other hand I'm not sure. Why don't you 
look that up in e.g. the Stroustrup book...

Christian