On 05 Nov 2014, at 17:37, Willem Ferguson <willemfergu...@zoology.up.ac.za> wrote:
Willem,
> 1) This patch has an unintended consequence: The ending cylinder pressure for
> the diluent cylinder (as seen on the equipment tab) is changed to reflect
> that of the ending pressure of the oxygen cylinder. The diluent cylinder
> index for the Poseidon diluent is the dreaded and infamous 1. We hardcode the
> cylinder IDs here while reading in the dive log because it is very specific
> to the Poseidon. In addition, even though these specific two cylinders have
> already been assigned to enum values of oxygen and diluent respectively, we
> are in the process of setting up the cylinders, so we cannot already use the
> functions that use these enum values.
> So: dive->cylinder[1].sample_end.mbar for this sample dive has a value of
> 141, that of the oxygen cylinder. The correct ending value for this variable
> is 137. I have carefully looked around the code around line 600 in file.c but
> cannot see the cause of this problem. Run the code with and without your
> patch and see the difference.
>
This is weird. For some reason the pressures for the O2 cylinder are shown even
when the gas name is “Air”. Have to investigate this further.
> 2) A question just to improve my understanding of the code. If the
> explicit_first_cylinder() result is diluent, does this mean that the deco
> requirements are calculated for the gas in the diluent cylinder? In this case
> the diluent is air, but the displayed ceilings do not (at first sight) appear
> to be shallower than that for air dives to the quivalent depths. For
> instance, if I simulate the sample dive as an air dive using the planner, the
> dive extended to 70 min for sufficient deco. So if the ceilings reflect the
> pn2 values at the various depths as actually calculated at each point on the
> profile, why does it matter whether one starts with cylinder 0 or cylinder 1?
It means that air is handed to fill_pressures as gasmix (for which then the
inert gas pressures are adopted according to the set point). So it should do
the correct thing. If you gave it O2 then the gas output would always be pure
O2 (and thus no deco obligation).
Best
Robert
--
.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oOo.oO
Robert C. Helling Elite Master Course Theoretical and Mathematical Physics
Scientific Coordinator
Ludwig Maximilians Universitaet Muenchen, Dept. Physik
print "Just another Phone: +49 89 2180-4523 Theresienstr. 39, rm. B339
stupid .sig\n"; http://www.atdotde.de
signature.asc
Description: Message signed with OpenPGP using GPGMail
_______________________________________________ subsurface mailing list subsurface@subsurface-divelog.org http://lists.subsurface-divelog.org/cgi-bin/mailman/listinfo/subsurface
