[boost] Re: uBLAS and expression templates

From: Benedikt Weber (weber_at_[hidden])
Date: 2002-06-30 04:29:30

> The problems you are seeing are not intrinsic to expression templates.

I fully agree. I was talking about the way expression templates are used in
uBLAS, not in general about expression templates. In uBLAS they are used to
avoid temporary vector an matrix variables, which is a performance
improvement only in certain cases while in other cases it is a degradation.
In many cases saving temporaries is crucial to avoid unnecessary
recalculation of subexpressions. As far as I understand, expression
templates give you the possibility to perform the evaluation in a way
different from what they would normally be evaluated, so you can use your
own optimization strategy. (They could possibly even be used to perform
blocked evaluation of matrix products?).

Benedikt