raptop changed the topic of #kspacademia to: https://gist.github.com/pdn4kd/164b9b85435d87afbec0c3a7e69d3e6d | Dogs are cats. Spiders are cat interferometers. | Космизм сегодня! | Document well, for tomorrow you may get mauled by a ネコバス. | <UmbralRaptor> egg|nomz|egg: generally if your eyes are dewing over, that's not the weather. | <ferram4> I shall beat my problems to death with an engineer. | We can haz pdf
<bofh>
23:44:38 <@egg|zzz|egg> hm i guess it's 1 because I'm only modeling the mean, and the number of frequencies I pick is how I estimate τ^2, not a different basis
<bofh>
1, yes.
<bofh>
23:49:18 <@egg|zzz|egg> bofh: if I'm only computing one coefficient of the dft, isn't it easier to do so naively from the definition? I don't see what I gain from the fft algorithms there
<bofh>
okay, I guess that is a good point.
<egg|zzz|egg>
bofh: also: is this estimator (2nd coeff of the appropriately normalized fourier transform, squared, divided by N) general porpoise in theory? what assumptions break it
<bofh>
like, give me a moment to think about that. it *should* be general porpoise under some assumptions, I'm just not sure which. I might actually ask a friend that's a proper statistician since I *know* I've seen this before but I can't for the life of me recall where or in what conteggst.
<egg|zzz|egg>
bofh: how do you have statistician friends and why are they not here,
<mlbaker>
do i even want to know what is going on hee
<mlbaker>
here
<egg|zzz|egg>
mlbaker: i have no idea what I'm doing, and I'm trying to estimate the uncertainty of the mean of a time series that clearly has a signal in it (but I don't give a damn about the signal, I just want to estimate the mean)
<egg|zzz|egg>
mlbaker: the purpose of the uncertainty is to limit the number of sigdec shown in a KSP mod :-p
<egg|zzz|egg>
mlbaker: however, i can neither into statistics nor fourier analysis
<mlbaker>
i'm confused
<mlbaker>
you have a time series
<mlbaker>
so you can compute the mean
<egg|zzz|egg>
yes
<egg|zzz|egg>
I want to estimate the error of the mean of this finite time series as an estimate of the mean of the actual infinite time series
<mlbaker>
okay
<mlbaker>
what's the infinite time series
<egg|zzz|egg>
here we're looking at the anomalistic period of a slightly perturbed orbit, computed as the times between periapsides over 4000ish orbits
<egg|zzz|egg>
what is it? probably a bunch of periodic things with mystery periods from third-body effects, kozai oscillation, the precessions, etc.
<mlbaker>
17:50 <@egg|zzz|egg> bofh: but then there's a part II to that paper, where he does basically the same paper but in---galaxy brain---tensor index notation
<mlbaker>
(A wild ROGER PENROSE appears!)
<egg|zzz|egg>
mlbaker: sadly there is no part III with the same paper again with squiggles
<mlbaker>
or as the french call it "notation des insectes"
<mlbaker>
i read the backlog a bit, still don't feel like i really understand the problem
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<egg|zzz|egg>
I can compute an approximation of the anomalistic period by taking the average of the periapsis-to-periapsis times over N orbits, but I would like error bars on that approximation of the anomalistic period
<mlbaker>
i think you need information about how the data is distributed to say anything
<mlbaker>
seems to me like you're roughly asking how quickly a finite mean converges to the true mean
<egg|zzz|egg>
well, importantly the data is very autocorrelated (it's pretty much a periodic signal!) https://i.imgur.com/SAgBNRi.png so this leads to the estimators for the variance of the mean based on serial covariances
<egg|zzz|egg>
which can in turn be approximated under some conditions by the low-frequency Fourier speggtrum
<kmath>
<PlanetTreky> "Potentially the first evidence of a terrestrial meteorite." ⏎ !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! https://t.co/YNOIVKdGmu
<bofh>
UmbralRaptor: ?
<bofh>
Don't we have a lot of terrestrial meteorites?
<bofh>
Or do you mean terrestrial *in origin*?
<UmbralRaptor>
bofh: the latter
<bofh>
what the hell how does that work.
<UmbralRaptor>
Well, it was found on the lunar surface…
<UmbralRaptor>
(Same way Lunar, Vestan, and Martian meteorites work. Something whacked earth hard and knocked a few chunks off.)
<SilverFox>
prolly the dinosaurs
<UmbralRaptor>
Dropping an asteroid on yourself to own the birbs.
<kmath>
<reverschansons> Jamais vais te donner haut ⏎ Jamais vais te laisser bas ⏎ Jamais vais courir autour et te déserter ⏎ Jamais vais te faire… https://t.co/8vnvIXiO7k
<kmath>
<jfbastien> Today's episode of "something I didn't know about C99": ⏎ ⏎ int derp(int arr[static const restrict volatile 5]); ⏎ ⏎ I kn… https://t.co/Yu130KvijB
<egg|zzz|egg>
whitequark: does that mean the syntax for a non-null pointer to T in C99 is T ptr[static 1]
<egg|zzz|egg>
and adding consts as appropriate, "ptr : constant access not null constant T" is T const ptr[static const 1]
<UmbralRaptor>
"I have chosen a method (from Alan Macdonald, private communication) that I think is both conceptually straightforward and exposes the most important conceptual issues."
<UmbralRaptor>
This is a line in a textbook, btw.
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<bofh>
UmbralRaptor: *blank stare*
<egg|zzz|egg>
bofh: meow
<UmbralRaptor>
bofh: All that for deriving the Lorentz transform.
<UmbralRaptor>
(Because TRIANGLE!)
<bofh>
UmbralRaptor: why does everyone's treatment of Spec. Rel. suck in a "this is unnecessarily complicated" way?
<UmbralRaptor>
Not sure
<egg|zzz|egg>
UmbralRaptor: triangle?
<egg|zzz|egg>
bofh: meow
<egg|zzz|egg>
UmbralRaptor: meow
<UmbralRaptor>
ACTION pets egg|zzz|egg with a hexagon ⌬
<UmbralRaptor>
egg|zzz|egg: special relativity works because of triangles. Look at the classic light clock eggsample.
<egg|zzz|egg>
UmbralRaptor: ah, the /topic triangles strike again
<bofh>
You mean light ones, right?
<bofh>
light CONES*
<bofh>
fucking hell I'd describe the inet right now as barely usable.
<SnoopJeDi>
UmbralRaptor, a few years ago we had to pile into a vehicle and drive ~15 hours to New Mexico for an APS section meeting on our advisor's whim. The upshot was that we got to see the most remarkably long-winded discussion of geometry ever.
<SnoopJeDi>
talk format was I think 10+2, this guy is on slide...5? explaining how this triangle is similar to that triangle and this is similar to that in laborious detail, and he got cut off.
<SnoopJeDi>
it was a pretty cool subject, too. electron beam shadowing effects. shame he didn't get to any of that because of all the "welcome to ray optics 100"
<kmath>
<bofh453> TIL "бнопня" is a meme on runet.
<egg|zzz|egg>
bofh: иТ ИС СУППОСЕД ТО БЕ ЦАПИТАЛИЗЕД ЛИКЕ ТХИС, СО ТХАТ цЫРИЛЛИЦ ВИТХ ТХЕ ХИГХ БИТ ДРОППЕД ТУРНС ИНТО А *ЦАСЕ-ИНЖЕРТЕД* ТРАНСЛИТЕРАТИОН.
<egg|zzz|egg>
whitequark: how cursed is taking ASCII, setting the 8th bit, and decoding that as КОИ-8 :-p
<whitequark>
egg|zzz|egg: (re bofh message) my eyeballs just melted
* egg|zzz|egg
pets whitequark
<bofh>
mine just melted too
<bofh>
and right, I did garble the capitalization, oops. >_<
<egg|zzz|egg>
my laptop just died and now it won't boot
<bofh>
for once I am not to blame
<egg|cell|egg>
Nevermind it's booting now
<egg|zzz|egg>
<whitequark> egg|zzz|egg: (re bofh message) my eyeballs just melted <bofh> mine just melted too << нОВ и АМ БЕЦОМЕ егг, ТХЕ ДЕСТРОЫЕР ОФ ЕЫЕБАЛЛС