From: David Abrahams (david.abrahams_at_[hidden])
Date: 2002-07-02 14:08:32
"Benedikt Weber" <weber_at_[hidden]> wrote in message
news:afssmk$3ms$1_at_main.gmane.org...
> Joerg
>
> I just want to remind you that there are many other expressions...that
should also evaluate efficiently.
Yes.
> like A*( B * (C * v))
That's no more difficult than A*(B*v) is. The ET machinery should
handle it, since this----------^ is just
Matrix-Expression * Vector-Expression.
Like this is: A*( B * (C * v))
---------------^
> or norm_2(A * (B * v))
By the same reasoning, this should not require any more temporaries than
norm_2(A)
does.
> Avoiding temporaries in all cases looks like a real challange, if it's
> possible at all.
It's usually possible, but not always desirable.
-Dave