Next round of api improvements.

[Dirk Hohndel]

On Wed, 2012-11-21 at 17:58 +0100, Jef Driesen wrote:
> >> CNS/OTU can be calculated from the samples
> >
> > IMHO, you can't if you don't have previous dive information as you 
> > don't
> > know the initial CNS.
> 
> True, but nobody says that an application can't take into account a 
> series of dives :-)

That's what the first set of code that I wrote for Subsurface was doing.
I ended up throwing that away because of some algorithmic issues, but I
will add a better version of it eventually. It will definitely walk the
whole dive list to determine how much residual CNS needs to be taken
into account (and interestingly enough, there appear to be conflicting
formulas for how to do that).

> But that doesn't mean we won't support it. We are just trying to see 
> what is out there, what users want to have, and then make a good 
> decision based on that.

:-)

> >> , but we can consider to
> >> support it too. I have no idea which devices record this in the 
> >> data. I
> >> know the Suunto's have this weird OLF (Oxygen Limit Factor) value, 
> >> which
> >> is either the CNS or OTU, whichever is higher. And I think the 
> >> Oceanics
> >> have a scale from 1 to 5 or something. So that might be a bit more
> >> difficult to support in a uniform way.
> >
> > If some devices do something their own way, i.e. OLF or 1-5 scale, 
> > then
> > ignore it until they document how to recalculate into CNS. For those 
> > who
> > really want to deal with such "inventions", there sill is raw data. 
> > The rest
> > of us will benefit from simpler (but still flexible) interface.
> 
> That's also how I think about it.

Then I guess we agree to disagree.

/D