Robert Helling helling at atdotde.de
Wed Jul 1 00:04:34 PDT 2015

Good morning Jan,

> On 01.07.2015, at 08:04, Jan Darowski <jan.darowski at gmail.com> wrote:
> Dirk: fine, I agree that these commits aren't of the highest quality.
> One of the reasons is that this work is based in huge part on the
> existing implementation which I had to discover part by part and which
> has a lot of strange solutions (including units and constants scaled
> all the time). The other reason is probably my negligence. I hope to
> have all of this repaired by Friday.

No problem. This is how coding works. You try things out and something works, something else doesn’t and has to be changed later. I believe Dirk’s comments are really about how you present things to the world: You should redo the commits in a way that it looks like you got everything right in the first place. In your situation now, I would start with all your patches together and then split everything into small meaningful patches with explanatory commit messages using git add -p. This should not be too painful. Just make sure that the code builds and runs without immediate crashes after each commit so people don’t run into problems when later bisecting.

>> There is one thing that I did not expect: I printed the final allowable
>> gradients and the deeper and longer the dives get, the gradients increase. I
>> must say I expected the opposite. But maybe that is my flawed understanding
>> of the model.
> Without thinking too much: it's fine for the deeper dives to have
> bigger gradients. The smaller the radius at the start of deco, the
> bigger the gradient (bigger pressure needed to make the nucleon turn
> into bubble). Gas saturation in the tissue increases slowly during the
> descent so if we descent quickly, nucleon shrinks a lot (gas pressure
> inside the bubble much bigger than saturation), so quick, deep descent
> -> big gradient.

OK, if we produce the correct plans then this is what the model is like (and my intuition was wrong).

> Longer time at the bottom should let the saturation increase, making
> the nucleon bigger and decreasing the gradient... But besides nuclear
> regeneration algorithm seems to completely ignore this part of the
> dive (the saturation increases so the first deco stop is deeper what
> increases deco time but that's not connected to the gradient). I will
> test this, maybe I'm missing something.

I think this whole bubble regeneration is totally useless as the half time is two weeks so it has no influence to any diving (at least during one day).

I will play some more with your code during the day but first some real work (paid).

Robert C. Helling     Elite Master Course Theoretical and Mathematical Physics
                      Scientific Coordinator
                      Ludwig Maximilians Universitaet Muenchen, Dept. Physik
                      Phone: +49 89 2180-4523  Theresienstr. 39, rm. B339

Enhance your privacy, use cryptography! My PGP keys have fingerprints
A9D1 A01D 13A5 31FA 6515  BB44 0820 367C 36BC 0C1D    and
DCED 37B6 251C 7861 270D  5613 95C7 9D32 9A8D 9B8F

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.subsurface-divelog.org/pipermail/subsurface/attachments/20150701/f89bd9ce/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 495 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <http://lists.subsurface-divelog.org/pipermail/subsurface/attachments/20150701/f89bd9ce/attachment-0001.sig>

More information about the subsurface mailing list