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Cham M
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Post #61by Cham » 17.10.2007, 17:26

The task isn't simple. As Fridger said, we have to identify the less reliable data (spectroscopic vs visual binaries), and remove it from the database. Then, we have to agree on a greek naming convention (KHI or CHI).
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Post #62by t00fri » 17.10.2007, 17:29

hank wrote:
t00fri wrote:But also we have to agree about the final Greek letter naming of some of the stars etc. It's just work that is straightforward for me but for the time being it has NOT top priority.
Sorry Fridger, I missed that part of your previous post. So there is more work to be done. Is this task on the list for 1.5.0? If it can't be completed in time, would it be better to leave the binary orbits out of 1.5.0 entirely?

- Hank


By God no. But why this hurry? When the release date seems to get closer, I will take some of my time, do the mods and commit the changes to CVS. It's as simple as that. Right now I am just doing other things. Why isn't that easy to understand? Perhaps Chris L. also does other things right now? Who knows. He did other things during the last 3 months, for example.


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Cham M
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Post #63by Cham » 17.10.2007, 17:34

t00fri wrote:If the teacher understands the meaning of two datasets that carry experimental uncertainties as every decent dataset does, the students could LEARN instead of being confused!


I'm afraid it isn't that simple. In the computer lab, the students may have to explore by themselves the stars around us (for example). Then, one of them fall on a wrong binary (with Celestia confused by two stars having the exact same name). The teacher would then have to lose some time explaining why it is like that, while the course was on another subject. This is not a good thing, in education.

The student may even ask why it isn't the same for the other binaries. It's clearly a deficiency in the binaries database, and nothing else, and should then be corrected ASAP. Please, don't use this database weakness as an excuse to give uncertainties examples in the classroom, it just doesn't make any sense !
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Post #64by selden » 17.10.2007, 17:40

Cham,

Since Celestia uses the Hipparcos database, the acronyms used by Hipparcos should continue to be used, with the spelling CHI

See HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index, Kostjuk N.D., Institute of Astronomy of Russian Academy of Sciences (2002), which is available at http://cdsarc.u-strasbg.fr/viz-bin/Cat?IV/27
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Cham M
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Post #65by Cham » 17.10.2007, 17:41

t00fri wrote:By God no. But why this hurry? When the release date seems to get closer, I will take some of my time, do the mods and commit the changes to CVS. It's as simple as that. Right now I am just doing other things. Why isn't that easy to understand? Perhaps Chris L. also does other things right now? Who knows. He did other things during the last 3 months, for example.


Fridger, nobody (not even Chris himself) knows about the releasing date. It may even take another full year. So why wait to the last minute, especially since many users out there can already use Celestia 1.5.0 from CVS ? Releasing a database long before the official release may even help the users to identify some other troubles, bugs, errors, etc (like what I already did for your DSO database, if you recall).
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Post #66by t00fri » 17.10.2007, 17:45

Cham wrote:Please, don't use this database weakness as an excuse to give uncertainties examples in the classroom, it just doesn't make any sense !


Please, Martin!

In case of both datasets for a doubled binary system, we are talking about measurements done with high amount of professionalism. Since the methods used AND inherent sources of uncertainty were totally different, some results also came out different (within the uncertainties). This gave rise to somewhat differing orbit displays for the same system.

But of course both sets of data are peer reviewed and highly acclaimed scientific results and in NO way reflect any kind of weakness of the database as you stated above. This must really be a joke.

++++++++++++++++++++++++++++++++
The real challenge would rather be to think about a method of how to visualize experimental uncertainties, such that the limits of our knowledge could be intuitively illustrated!
++++++++++++++++++++++++++++++++

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Post #67by ElChristou » 17.10.2007, 17:48

Idea: waiting for the fix of this problem, if your topic is not about binaries, just remove the data sets to avoid those questions and the day you want to do a speech on binaries, you can always do a short introduction on the actual problem to avoid again some irrelevant question... What do you think?
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Post #68by Cham » 17.10.2007, 17:51

selden wrote:Cham,

Since Celestia uses the Hipparcos database, the acronyms used by Hipparcos should continue to be used, with the spelling CHI


I agree. I prefer CHI over KHI. Chi is usually what I'm writing (when I'm not using the greek letter).
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Post #69by hank » 17.10.2007, 18:01

t00fri wrote:I could just add a few PERL statements rerun the scripts and the doubles would be gone. That's so trivial, not worth loosing even one sentence.
If a trivial change to the PERL scripts could segregate the duplicates into separate files, then the user could choose which file(s) of duplicates to load by modifying the Celestia configuration.

t00fri wrote:What is a non-trivial astrophysics question, however, is which dataset to cross out and which to retain. Since that selection does not work dynamically, a physics based decision is required.

This in turn requires literature research and reading of respective papers...

So please don't mix up simple coding issues and underlying non-trivial astrophysics questions.

It's really more a question of software architecture and standard configuration policy. I'm trying to separate these issues precisely because it may not be possible to address the non-trivial astrophysics questions for 1.5.0.

- Hank

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Cham M
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Post #70by Cham » 17.10.2007, 18:04

The temporary solution to this problem, in my case, was to remove the conflicting stars. I arbitrarily removed mainly the spectroscopic conflicting stars, and some visual binaries, leaving the others untouched. I did not used any special argument about this or that conflicting binary, before removing it from the database (actually, they are all there in the STC files. I simply commented them out using # in their definition). That way, I solved the conflict in Celestia and the binaries are now all looking fine. However, I'm still uncomfortable with the names (KHI vs CHI), since I don't know how many stars (not just the binaries ?) which have a "weird" greek name.
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Post #71by t00fri » 17.10.2007, 19:17

hank wrote:
t00fri wrote:I could just add a few PERL statements rerun the scripts and the doubles would be gone. That's so trivial, not worth loosing even one sentence.
If a trivial change to the PERL scripts could segregate the duplicates into separate files, then the user could choose which file(s) of duplicates to load by modifying the Celestia configuration.

In most cases, the users are NOT qualified to decide this!
Also many users would not be able to run PERL from the datasets, because of lack of experience.

t00fri wrote:What is a non-trivial astrophysics question, however, is which dataset to cross out and which to retain. Since that selection does not work dynamically, a physics based decision is required.

This in turn requires literature research and reading of respective papers...

So please don't mix up simple coding issues and underlying non-trivial astrophysics questions.
It's really more a question of software architecture and standard configuration policy.

Come on! In a trivial manner EVERY physics decision in software can be reduced to a configuration policy issue ;-)


I'm trying to separate these issues precisely because imay not be possible to address the non-trivial astrophysics questions for 1.5.0.

- Hank

Why? Do you have some hidden expertise here? I told you that I can solve it and will take the necessary time when the next (pre)release date approaches. Since this date does not seem to be imminent and I have plenty of other things to do, I wrote that I will take my time.

As in all the years before, I am waiting to hear --well in advance-- about the next prerelease date from Chris. That's all that is needed and everyone can AT LAST start planning more concretely.

If it can't be completed in time, would it be better to leave the binary orbits out of 1.5.0 entirely?


What? I hope you are aware that my binary orbits (visualbins.stc & spectbins.stc) are an integral part of the Celestia distribution since version 1.40 already (2005)! How about informing yourself more concisely first? We are NOT at all talking about a new feature here ;-)

So you were advocating to take my orbits out again, after Chris L. spent months to code all the binary star stuff! And just because Cham made such a fuzz about these few doubles? My God where is all this going.

I could also suggest to take my 10000+ galaxies out as well, since there are possibly also some remaining unknowns... The file is called deepsky.dsc, just in case ;-)

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Post #72by hank » 17.10.2007, 19:31

t00fri wrote:But why this hurry? When the release date seems to get closer, I will take some of my time, do the mods and commit the changes to CVS. It's as simple as that. Right now I am just doing other things. Why isn't that easy to understand?

We're coming up on two years since the last release of Celestia. And it's not as if no work has been done. There have been a number of important additions to Celestia (yours included), which have been practically complete for some time, but are still only available in prerelease versions.

I think Celestia would benefit if the 1.5.0 release could made as soon as possible, with a plan and process for continuing releases at roughly regular intervals of no more than about six months. I hope this might be possible. But it requires focusing on the testing, debugging and cleanup necessary to finalize the release.

If you can finish up the binary star work for 1.5.0, as you indicate, that would be great. If not, we would need a contingency plan. As a worst case, the binary star work would need to be deferred to a later release.

Earlier I had the impression that you had decided not to do any further work on Celestia, but would concentrate instead on your other projects. If my impression was mistaken, or you've changed your mind, I would be very pleased. Not because I think your new projects aren't important, but because I'd really like to see your previous contributions to Celestia finally get released, and your help is needed for that.

- Hank

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Post #73by t00fri » 17.10.2007, 20:05

hank wrote:If you can finish up the binary star work for 1.5.0, as you indicate, that would be great. If not, we would need a contingency plan. As a worst case, the binary star work would need to be deferred to a later release.

Hank,

I think you are really "overqualifying" yourself...
Are you now speaking as Chris L.'s new "manager"? ;-) .

OK. Please note: I am not one of your "volunteers" as I clearly indicated by not signing onto that list. Being a Celestia co-author and one of the most longstanding developers besides Chris, I think I don't need a "dispatcher" to do the planning that I consider adequate. I would simply urge Chris to come forward with a realistic planning date and we can spare this incompetent chatting here entirely!

Earlier I had the impression that you had decided not to do any further work on Celestia, but would concentrate instead on your other projects.

If I had any plans in that direction, I would certainly not discuss that with you after developing for Celestia since almost 6 years... It is certainly correct that I am involved in other projects, but so is Chris L. right?

One more word about your "contingency plan, and I will right away delete my whole binary star data base from CVS.

That should be the cleanest way to make clear (e.g. to Cham and others) what you are talking about here. I am NOT the person to threaten with "contingency" plans, notably in cases that are completely exaggerated.

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Post #74by hank » 17.10.2007, 20:20

t00fri wrote:In most cases, the users are NOT qualified to decide this!
Also many users would not be able to run PERL from the datasets, because of lack of experience.
I think users are qualified to decide what their needs are, and that we should make it easy for them to adapt Celestia to their own needs.

t00fri wrote:Why? Do you have some hidden expertise here? I told you that I can solve it and will take the necessary time when the next (pre)release date approaches. Since this date does not seem to be imminent and I have plenty of other things to do, I wrote that I will take my time.

As in all the years before, I am waiting to hear --well in advance-- about the next prerelease date from Chris. That's all that is needed and everyone can AT LAST start planning more concretely.
I was not asserting any expertise, or questioning your ability to solve the scientific question, but rather was questioning your willingness to do the work as needed for 1.5.0. As I explained in my previous post, I had the impression that you had decided not to do any further work on Celestia. Also, although you've now indicated your willingness, it's not clear to me how much advanced notice you would need. So it seems possible that resolving the scientific question may still not be feasible for 1.5.0.

t00fri wrote:So you were advocating to take my orbits out again, after Chris L. spent months to code all the binary star stuff! And just because Cham made such a fuzz about these few doubles? My God where is all this going.

I could also suggest to take my 10000+ galaxies out as well, since there are possibly also some remaining unknowns... The file is called deepsky.dsc, just in case ;-)

Fridger, I was not advocating that the binary orbits be taken out. I was asking you what you wanted done. I personally would prefer to see them stay in. But I was concerned that you might object if the duplicate issue were resolved without a scientific justification meeting your approval.

If you are willing and able (time-wise) to do the necessary cleanup for 1.5.0, then there's no problem.

- Hank

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Post #75by t00fri » 17.10.2007, 21:04

hank wrote:
t00fri wrote:In most cases, the users are NOT qualified to decide this!
Also many users would not be able to run PERL from the datasets, because of lack of experience.
I think users are qualified to decide what their needs are, and that we should make it easy for them to adapt Celestia to their own needs.
Sorry, but we established certain scientific standards in Celestia that are NOT up to you to modify or decide about. So the official distribution is to provide the public with a data base that is up to high scientific standards. That's the target whether you like it or not.

t00fri wrote:Why? Do you have some hidden expertise here? I told you that I can solve it and will take the necessary time when the next (pre)release date approaches. Since this date does not seem to be imminent and I have plenty of other things to do, I wrote that I will take my time.

As in all the years before, I am waiting to hear --well in advance-- about the next prerelease date from Chris. That's all that is needed and everyone can AT LAST start planning more concretely.
I was not asserting any expertise, or questioning your ability to solve the scientific question, but rather was questioning your willingness to do the work as needed for 1.5.0.

Unlike that of others, my reliability record is proven and very good! Let me just remind you of the tight organisation and release of our Celestia-FT-1.x releases with the new galaxies during Chris' last hiding period ~ 2 years ago. So you did not have ANY reasons to doubt my statements. I have NEVER so far missed a release as to work that was due from my side.
As I explained in my previous post, I had the impression that you had decided not to do any further work on Celestia. Also, although you've now indicated your willingness, it's not clear to me how much advanced notice you would need. So it seems possible that resolving the scientific question may still not be feasible for 1.5.0.

But that's Chris' business NOT yours. Do with your "volunteers" whatever you like, but please leave me in peace. You are just not the right person for that sort of talking...

If you are willing and able (time-wise) to do the necessary cleanup for 1.5.0, then there's no problem.

- Hank


So if for some reason I didn't manage, you still indicate that there is a problem. AHA.

Please could you explain us a bit more clearly, with what authority you are making such far reaching statements, that would deprive Celestia of ALL it's binary orbit data if you keep going on this way??

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Post #76by ElChristou » 17.10.2007, 21:37

Guys indeed I don't see the problem. The only user here who as repeatedly ask for the review of those binaries files is Cham, and for now he do have a solution to manage his courses. Fridger know perfectly what is the problem, so it's up to him to do the work when he decide to do so. IF someone is able to achieve with the same level of exigence the work, he can propose here his own files. If not then we must wait for Fridger's one. AS those files are no crucial for the release of 1.5 (no bugs here), I really don't see why all this blabla bla... :?
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Post #77by Cham » 17.10.2007, 21:53

Guys, this discussion is begining to be off-topic.

We were talking about a dozen of doubles and stars with some inadequate greek names in the binaries database. There are much more binaries in there without any problem (AFAIK). I'm simply asking that the conflicting 15 binaries be fixed. See my list on this page :

http://www.celestiaproject.net/forum/viewtopic.php?t=11311

So I suggest that :

1- the greek names be fixed according to the hipparcos naming convention (CHI, instead of KHI, for example), as suggested by Selden.

2- One of each conflicting binaries be removed (or commented out) from the database, while we leave untouched the other one (visual or spectroscopic). There are 5 conflicting binaries (stars with the same name).

3- the stars with different names (and associated to the same stellar object) be identified, and some of them removed in the same way as in #2. There are 10 conflicting stars with different names in the database.

For points #2 and #3, we need to choose which one to remove (or to be commented out in the STC files) : the conflicting visual binaries or the conflicting spectroscopic binaries ?

I think the discussion should stay on that track. Is that reasonable or not ?

ElChristou wrote:AS those files are no crucial for the release of 1.5 (no bugs here), I really don't see why all this blabla bla... :?


On the contrary, there are 5 conflicting stars which gives totally wrong orbital configurations. There are 5 pairs of stars with identical names. This makes Celestia to become confused.
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Post #78by t00fri » 17.10.2007, 22:07

Martin,

sure enough this will happen, as you know very well! It happened before completely smoothly. I am grateful that you spotted further tricky doubles in the datasets as well as that minor clash with the greek letters. I also do prefer CHI etc.

I even promise that I'll try to be reasonably fast with providing the fixes.

-------------------------------------------------------------------
But I DON'T have myself implicitly or explicitly
threatened by anybody that there might be a problem of having my binary orbit data prevail in the distribution, if I don't manage to observe some (unspecified) timeline for the fixes. Notably if that person is not authorized to make such far reaching statements.
--------------------------------------------------------------------
That's not the kind of "English" I do understand!

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Post #79by ElChristou » 17.10.2007, 22:17

Fridger, I'm pretty sure there is miss-use for some words here and there. Let's not start a flame war...

Again, those fix are not sooo urgent, even if Celestia get "confused" it's only on a few stars, there is not a major bug at this level...
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Post #80by hank » 17.10.2007, 22:39

t00fri wrote:Sorry, but we established certain scientific standards in Celestia that are NOT up to you to modify or decide about. So the official distribution is to provide the public with a data base that is up to high scientific standards. That's the target whether you like it or not.
In fact I'm strongly in favor of high scientific standards for Celestia's standard databases. That isn't the issue. The issue is how to fix the immediate problems with the current version of the binary star database for the 1.5.0 release. If you can do it, that would great. If not, some other solution would be necessary. I never intended to suggest anything more than that.

t00fri wrote:Unlike that of others, my reliability record is proven and very good! Let me just remind you of the tight organisation and release of our Celestia-FT-1.x releases with the new galaxies during Chris' last hiding period ~ 2 years ago. So you did not have ANY reasons to doubt my statements. I have NEVER so far missed a release as to work that was due from my side.
I did not mean to question your reliability in any manner. You past record cannot be questioned.

t00fri wrote:But that's Chris' business NOT yours. Do with your "volunteers" whatever you like, but please leave me in peace. You are just not the right person for that sort of talking...
Chris has always been very receptive to collaboration and I have no reason to believe that won't continue.

t00fri wrote:So if for some reason I didn't manage, you still indicate that there is a problem. AHA.
If you don't manage to do the cleanup, and no else does it, then yes, the problem with the database would remain.

t00fri wrote:Please could you explain us a bit more clearly, with what authority you are making such far reaching statements, that would deprive Celestia of ALL it's binary orbit data if you keep going on this way??

Bye Fridger

Fridger, I really hope you won't remove the binary orbit data from CVS just because I've annoyed you. I certainly didn't intend to do so.

- Hank


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