From: Matthias Troyer (troyer_at_[hidden])
Date: 2006-08-21 03:43:22


On Aug 21, 2006, at 7:20 AM, Andy Little wrote:
>>> In fact you can do in place addition of quantities of course, but
>>> not
>>> multiplication, or at least not without low level manipulations.
>>>
>>> It sounds like I am arguing against my own library. I'm not, but I
>>> am pointing
>>> out that there are different considerations when using quantities
>>> and you may
>>> not ( in fact probably wont) get as good a performance as from
>>> using inbuilt
>>> floats. Overall Quan is much more fun to use than floats though,
>>> and I have
>>> enjoyed using it so far where possible..
>>
>> In fact it seems to me that you are much better off using a nice
>> linear algebra library that makes use of expression templates.
>
> To be honest you have lost me here.
> Are you now saying it would be better for me to ditch Quan and
> start writing a
> linear algebra library for floats that uses E.T?

No, I'm saying: don't worry about temporaries in your vector
expressions but just use an expression template based library with
your Quan types. There should be no problem.

Matthias