Re: Kronecker products as objects?

[David Bateman]

Soren Hauberg wrote:
> > function retval = double (KP)
> >   if (isempty (KP.full))
> >     KP.full = kron (KP.A, KP.B);
> >   endif
> >   retval = KP.full;
> > endfunction
> >
> > then use the double function in the places you used full in your code. 
> > In that way your knonprod object can be pretty much agnostics whether 
> > its treating full or sparse matrices internally.
> >     
>
> But then I can't handle complex matrices, right? I am unsure about the
> 'double'. Is it supposed to convert back into either a sparse or a full
> matrix or should it just ensure that that the matrices are double, i.e.
>   

Complex values are of the class "double". You don't loose the complexity 
of a value with the "double" method. You need to use "real" for that ;-) 
...

> function retval = double (KP)
>   retval = kronprod (double (KP.A), double (KP.B));
> endfunction
>   
Yes that will work fine if you don't want to cache the values and it 
should replace your use of  "full" in various places.. The full function 
is to return a full rather than sparse matrix.

D.