Re: *****SPAM***** Re: Cylinder pressure interpolation and end pressure display for CCR
On Sun, Nov 9, 2014 at 7:23 AM, Willem Ferguson willemfergu...@zoology.up.ac.za wrote: These are real readings taken with accurate pressure sensors on both the oxygen and diluent cylinders. Is the real-life situation perhaps a bit different from the expected theoretical situation? You guys have the experience. Certainly one cannot ignore the real measurements? Sorry. Didn`t figure it out you were talking about real measurements. To interpolate them, I believe we should use linear interpolation, no matter if we are dealing with oxygen or diluent. But surely I`m not following this issue as closely as I should ;) Rodrigo ___ subsurface mailing list subsurface@subsurface-divelog.org http://lists.subsurface-divelog.org/cgi-bin/mailman/listinfo/subsurface
Re: Cylinder pressure interpolation and end pressure display for CCR
On Sun, Nov 9, 2014 at 5:49 AM, Willem Ferguson willemfergu...@zoology.up.ac.za wrote: As far as the present implementation is concerned, I suspect it would be fairly easy (not simple) to to changes. We just need to agree on the principle of interpolation for the diluent. I was initially proposing a method that would use the regular OC depth dependent interpolation method with one modification: only the samples that represent an increase in depth to be considered, i.e., when ascending or maintaining depth, we would consider diluent consumption as zero. This method creates the problem of separating what actually is a depth increase and what is simply noise in depth reporting. Two methods where suggested to solve this issue: * a threshold (3 feet? something changeable by the user on preferences?) that would define the minimum depth change that we would actually consider a depth increase * a 1 minute time average depth (suggested by Dirk). I like Dirk`s idea but I believe any one of them would work. Regarding the graph you posted Willem, I believe that during ascends and fixed depths periods, the diluent graph should be a perfect horizontal line (no consumption as I mentioned above). Regards, Rodrigo ___ subsurface mailing list subsurface@subsurface-divelog.org http://lists.subsurface-divelog.org/cgi-bin/mailman/listinfo/subsurface
Re: *****SPAM***** Re: Cylinder pressure interpolation and end pressure display for CCR
On 09/11/2014 15:10, Rodrigo Severo wrote: On Sun, Nov 9, 2014 at 5:49 AM, Willem Ferguson willemfergu...@zoology.up.ac.za wrote: As far as the present implementation is concerned, I suspect it would be fairly easy (not simple) to to changes. We just need to agree on the principle of interpolation for the diluent. I was initially proposing a method that would use the regular OC depth dependent interpolation method with one modification: only the samples that represent an increase in depth to be considered, i.e., when ascending or maintaining depth, we would consider diluent consumption as zero. This method creates the problem of separating what actually is a depth increase and what is simply noise in depth reporting. Two methods where suggested to solve this issue: * a threshold (3 feet? something changeable by the user on preferences?) that would define the minimum depth change that we would actually consider a depth increase * a 1 minute time average depth (suggested by Dirk). I like Dirk`s idea but I believe any one of them would work. Regarding the graph you posted Willem, I believe that during ascends and fixed depths periods, the diluent graph should be a perfect horizontal line (no consumption as I mentioned above). Regards, Rodrigo ___ subsurface mailing list subsurface@subsurface-divelog.org http://lists.subsurface-divelog.org/cgi-bin/mailman/listinfo/subsurface Thanks, Rodrigo, These are real readings taken with accurate pressure sensors on both the oxygen and diluent cylinders. Is the real-life situation perhaps a bit different from the expected theoretical situation? You guys have the experience. Certainly one cannot ignore the real measurements? Kind regards, willem ___ subsurface mailing list subsurface@subsurface-divelog.org http://lists.subsurface-divelog.org/cgi-bin/mailman/listinfo/subsurface
Cylinder pressure interpolation and end pressure display for CCR
Robert, Specifically for Poseidon input, one needs to know which is the oxygen and which is the diluent. Like, I suppose, for any specific machine there will be a particular assignment of cylinders. Nowhere outside of the code that specifically reads Poseidon CSV do I use specific cylinder assignments as numbers. Does this make sense at all? Kind regards, willem On 08/11/2014 16:21, Robert C. Helling wrote: Willem, Am 08.11.2014 um 13:34 schrieb Willem Ferguson willemfergu...@zoology.up.ac.za: in file.c, for Poseidon input, ensure that the cylinder index is hard-coded by setting sample-sensor to 0. 2) For the three cases above, ensure that function populate_pressure_information() in gaspressures.c assigns the correct cylinder indices. This is performed by using a small lookup-table, rather than using complex if--else constructs. I thought we had decided against using magic numbers. Why would you force a specific number rather than setting the appropriate label? Best Robert -- Willem Ferguson Director: Centre for Environmental Studies, University of Pretoria Tel: 012-4202017 / 012-4204048 e-mail: willemfergu...@zoology.up.ac.za ___ subsurface mailing list subsurface@subsurface-divelog.org http://lists.subsurface-divelog.org/cgi-bin/mailman/listinfo/subsurface
