Re: [boost] [pqs] units conversion and serialization.

From: Andy Little (andy_at_[hidden])
Date: 2006-06-19 16:52:11

"Janek Kozicki" <janek_listy_at_[hidden]> wrote in message 
news:20060618012322.3c3a0a29_at_absurd...
> Hello,
>
> Actually when I was writing a review I have written a leghty paragraph
> about unit scaling during serialization. But later I decided that review
> is not a good place to put it, so I'm pasting it now below:
>
>
>
>    One of my first thoughts was about making it easier for the end user to
> perform serialization, more precisely, consider the first screenshot in
> following URL:
>
>    http://yade.berlios.de/index.php?m=700:70

*Even* with t1_quantity (fixed units) you would get some 'free' units output ;-)

[cut user settable units]

>    I presume that only t2_quantity gives what I need above. But if
> conversion from t2_quantity to t1_quantity is possible, then maybe all
> that t1_quantity -> t2_quantity -> t1_quantity conversions could be
> hidden from the user behind the interface? So that only those two
> interface functions I mentioned above will be used.

Yes. t2_quantity should be useful for that. Typically you can make a units 
map<unit_string, quantity_w_unit>.
t1_quantity is useful to describe the quantity_w_unit, t2_quantity to hold 
runtime unit and convert to t1_quantity
I had an example, but in a previous version of PQS. Not tried to make a GUI 
widget of it yet though ;-)

> PS: please note that this comment is *old* so I'm still using here old
> names (t1, t2,...) and other stufff that likely is already decided that
> it will be modified to better suit the needs/suggestions/comments of all
> people. But the need for described above interface still remains.

Yep ... todo!

regards
Andy Little