UmbralRaptor 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> … one of the other grad students just compared me to nomal O_o | <ferram4> I shall beat my problems to death with an engineer.
<egg>
UmbralRaptor: nomal is interested after watching a performance, and dejected after being kept from alcohol for too long.
<egg>
right now she seems to be putting Lenses: a brief introduction back on a shelf
* Ellied
sends Nomal a copy of "How Snakes Work"
<egg>
O_o
* egg
suspects Nomal would feel anxious about that
<Ellied>
Dear Nomal: Though the search was long, I was able to recover a copy of this text. I'm sure I don't need to tell you why I recommend reading it sooner than later. Best of luck, Ellie D. Greening, Department of Physics and Applied Thaumatology.
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<UmbralRaptor>
!choose study|done for the night
<Qboid>
UmbralRaptor: Your options are: study, done for the night. My choice: study
<egg>
UmbralRaptor: so, I'm expanding the floor of the upper tavern with 3x3 housing, but I'm not sure what to do with the 1x3 rooms that will remain (they open on the dining room directly too, so that's a bit weird, and since they're 1x3 they can't reasonably be upgraded to 3x3 without getting weird 2-door rooms)
<egg>
I guess I could just break the internal walls and store food and drink behind those doors, but I'm wondering whether there's a better idea
<UmbralRaptor>
alcohol/food storage make sense.
<egg>
UmbralRaptor: there are also blocks like that in areas that don't lead to dining rooms, but I guess appropriate storage/manufactures can go there
<egg>
e.g. on the starwatch of oxen floor, bookbinders and paper stores
<egg>
I don't actually have much of a bookbinding industry going on, mostly they write on scrolls
<egg>
not sure they've been publishing much lately
<egg>
ah one engineer is writing about probing
<egg>
about the surgical method of probing... why is it an engineer writing this book
<egg>
well scroll
<egg>
there's also an astronomer writing about probing independently at the same time
<egg>
the chemist Domas baroness of Ancientbird is busy forging gold goblets in the depths of the fortress instead of doing research >_>
<kmath>
<ObservatoryCats> Hi cat folks: any astronomers with cats want to run this account from May 29-June 4? It's super easy and everyone loves guest purr-ators.
<UmbralRaptor>
egg: Is the astronomer writing about probing as in a grant proposal?
<egg>
UmbralRaptor: I think it's surgery too
<egg>
UmbralRaptor: also, ObservatoryCats!
<UmbralRaptor>
blarg
<UmbralRaptor>
Hadrosaur surgery?
<egg>
probably
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<oeuf>
staff at starwatch of oxen: 11 medical doctors, 6 engineers, 98 miscellaneous scholars, 6 scribes
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oeuf is now known as egg
<egg>
SnoopJeDi: there's also the mayor, I think he's an astronomer
<egg>
he spends most of his time handling scholarship/citizenship applications
<egg>
UmbralRaptor: in entertainment there's also 76 dancers+musicians+poets+other performers though
<egg>
UmbralRaptor: also 50 in the militia
<egg>
and 10 cooks to feed all that
<egg>
;rpn 98 11 6 6 + + +
<kmath>
egg: 121.0
egg is now known as egg|zzz|egg
<UmbralRaptor>
egg|zzz|egg: s/mayor/provost/
<Qboid>
UmbralRaptor thinks egg|zzz|egg meant to say: UmbralRaptor: also note the golden office and dining room of the baroness, on either side of the amphitheatre; the provost has his quarters, office, and dining room opposite the amphitheatre from the room with the marble tables
<UmbralRaptor>
uhm
<UmbralRaptor>
Note to self: qboid does not track nick changes.
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<kmath>
<Sidragon1> Proposition: New Clearance levels: S TS TS/SCI VL/FFTP (Vendor Lost/ Found on FTP server) WTF/G (Google Indexed TS/SCI)
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<egg|work|egg>
bofh: why does one solve Kepler's equation instead of computing directly the true anomaly from the mean anomaly? if you're already plugging a weird equation into a solver, why the intermediate step followed by trig functions?
<bofh>
because there's no nice eq'n that you can solve as far as I kmow that directly gives you the true anomaly?
<bofh>
(besides, you can do a lot of things directly from the eccentric anomaly. radius and inetsntaneous velocity for instance, off the top of my head).
<egg|work|egg>
bofh: well Kepler's equation isn't nice either
<egg|work|egg>
I've been able to find a total of one code snippet for orbits either side of e = 1, and that's a hardcoded expansion of three terms of some random taylor series >_>
<egg|work|egg>
so I'd be willing to believe that there's just a good bit of cargo-culting going on when doing the Keplerian -> Cartesian conversion
<bofh>
oh, no doubt.
<bofh>
said Taylor series is probably truncated Lagrange inversion series for Kepler's Eq'n composed with eccentric -> true anomaly to a few terms
<egg|work|egg>
bofh: yeah, eventually it all boils down to time->true anomaly (assuming you're using the true anomaly, which makes sense)
<bofh>
Yeah, I usually use r = a*(1 - e*cos(E)) instead
<bofh>
mostly b/cI can avoid having to dick around w/arctan to get \nu
<egg|work|egg>
bofh: and frankly since a solver is involved, I don't really see why not solve for true anomaly(time)
<egg|work|egg>
bofh: but arc tg is nice
<egg|work|egg>
like, the 2-param arc tg is about as well-behaved as you can get
<bofh>
(tho usually I don't need r so much as v, given my main use of Keplerian elements is calculating doppler shifts)
<bofh>
also jesus fuck doppler correction when both emitting source and receiver are moving and SR is relevant is a pain in the arse.
<bofh>
(heck, GR becomes slightly relevant, solar gravity potential wrt Earth gives you about 1.5Hz of a shift for, say Voyager 1 on X-Band)
<egg|work|egg>
!wpn bofh
* Qboid
gives bofh a killing pen
<bofh>
!wpn egg
* Qboid
gives egg a vanadium obsolete ?
* UmbralRaptor
is amused that GR is relevant to getting Voyager data.
UmbralRaptor is now known as QuantizedRaptor
<egg|work|egg>
QuantizedRaptor: thoughts on the Keplerian -> Cartesian cargo cult^W^W conversion?
<QuantizedRaptor>
Afraid I've only seen the classical approach to getting true anomaly.
<egg|work|egg>
QuantizedRaptor: and how do you do either side of e=1?
<QuantizedRaptor>
It only involved e<1 >_>;;
<egg|work|egg>
>_>
<egg|work|egg>
but with e > 1 you get fun things like Voyager 1's mean anomaly of thousands of degrees :D
<QuantizedRaptor>
?
Thomas|AWAY is now known as Thomas
<egg|work|egg>
!wpn Thomas
* Qboid
gives Thomas a Laguerre Lizzie
<egg|work|egg>
!wpn QuantizedRaptor
* Qboid
gives QuantizedRaptor an inductive guillotine
* QuantizedRaptor
gives the lizzie an associated Legendre polynomial.
<QuantizedRaptor>
!wpn -add:adj guillotine
<Qboid>
QuantizedRaptor: Adjective added!
<egg|work|egg>
bofh: oh, with my "more elements" pull request, principia probably doesn't compile if you normalize its source code by NFKC or NFKD :D
<egg|work|egg>
(because ϖ gets compatibility-normalized to π, and both are used)
<bofh>
why would you use the former at all tbh?
<egg|work|egg>
bofh: it's the symbol for longitude of periapsis
<egg|work|egg>
which is why it gets used in that pull request
<egg|work|egg>
bofh: I think it also appears in some standard notation relating to Coxeter groups? I don't remember
<kmath>
<mhoye> Trying to resurrect old proprietary hardware is the worst. So, hey, what's everyone's favorite quasi-legal firmware archive site?
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<Sarbian>
Guess who just found out that his old VM disk layout is freaking stupid and will make it a pain to convert ?
<egg|afk|egg>
sarbut sarbian
egg|afk|egg is now known as egg
<Sarbian>
Hoy egg of the white mountains
* Ellied
was bitten by a radioactive soldering iron :0
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QuantizedRaptor is now known as ContinuousRaptor
<e_14159>
Ellied: Now you can... solder stuff really well?
<ContinuousRaptor>
I assume this also means stabbing and burning things.
<egg>
ContinuousRaptor: are you differentiable
<egg>
!seen whitequark's cat
<Qboid>
egg: I haven't seen the user whitequark's cat yet.
<Ellied>
e_14159: my superpowers are 1. soldering fairly well (could do that already), 2. feeling mild pain on the inside of my wrist when objects are very nearby, 3. mystical knowledge of such things as "soldering iron tips are hot" and "adjusting their cords should be done with more care and less panache than I did that time"
<ContinuousRaptor>
egg: as opposed to quantized
ContinuousRaptor is now known as UmbralRaptor
<egg>
Ellied: hmmmm >_>
* egg
pets UmbralRaptor with a cat
<UmbralRaptor>
The cat survives!
* UmbralRaptor
should yoink one of the school's cats and stare at Jupiter tonight.
<egg>
UmbralRaptor: hmm, I wonder whether we can observe at the same time
<egg>
!wa degrees of longitude between Zurich and Kansas City
<Qboid>
egg: Seems that Wolfram is unable to understand that.
<UmbralRaptor>
Let's see… 2100 my time is 0200 UTC…
<UmbralRaptor>
!wa Zurich UTC offset
<Qboid>
UmbralRaptor: Seems that Wolfram is unable to understand that.
<bofh>
oh. well yes, hyperbolic* is usually just usual equations at ix
<egg>
yup
<bofh>
see: tanh vs tan, I0 vs J0, etc
<egg>
yup, see also how the Kepler equation turns into hyperbolic trig for hyperbolae
<egg>
and the imaginaries in there just come from Sqrt(1-e) and the like being imaginary
<egg>
I mean, this set ℝ ∪ iℝ *is* fairly convenient even though it's a standard issue algebraic structure
<soundnfury>
egg: √ℝ ?
<egg>
soundnfury: yeah that's pretty much how it arises
<soundnfury>
egg: hence I think that should be its name
<egg>
but how do you pronounce that
<egg>
I'm pretty sure √ is not allowed in C++ identifiers
<soundnfury>
"the square root of R"
<soundnfury>
egg: You amaze (and disgust) me
<soundnfury>
it's hardly a reserved character!
<soundnfury>
if it's not syntactically relevant, it should be allowed in identifiers. Otherwise, why bother having Unicode identifiers at all?
<egg>
nah but they disallowed ranges (instead of categories, because they didn't refer to Unicode, because WG21 haven't invented "the documents in the note blah blah" like WG9)
<soundnfury>
once again, we learn that C++ sucks
* soundnfury
runs
<egg>
oh I agree, all languages do
<egg>
in different and entertaining ways
<Ellied>
my uni has all these incredibly shitty (by modern standards) LEDs in the electronics lab. I think they date back from when cheap mass-produced LEDs were a very, very new thing.
<Ellied>
they're the type of thing where the green ones are just yellow diodes in a green plastic package, and they're so dim you can barely see that they're on in a well-lit room with 20 mA going through them.
<Ellied>
(turn up the current any higher, and then they stop emitting altogether because they're on fire)
<soundnfury>
Ellied: you mean they become SEDs? And then DEDs?
Thomas is now known as Thomas|AWAY
<bofh>
Ellied: oh, you mean Gallium Phosphide turds?
<egg>
bofh: the reason why I'm pondering those numbers is that right now I have a whole lot of Keplerian elements of the form foo, hyperbolic_foo, where one of foo and hyperbolic_foo is NaN and the other isn't
<egg>
(also a special case for semiminor_axis, whose hyperbolic version is impact_parameter)
<soundnfury>
egg: those numbers lie on the axes of the Argand diagram, the cardinal compass points so to speak, so maybe you could call them "cardinal numbers" :P
<soundnfury>
"Simple complex numbers", because it's not like anyone invented simplices to confuse that with
<soundnfury>
egg: these numbers of yours. Are they ever negative (in whichever part is nonzero)?
<soundnfury>
or are they always on the positive branch of the surd?
<egg>
um, the hyperbolic mean anomaly can be I think (bofh?)
<kmath>
<admittedlyhuman> @m1sp wait, they implemented gay *livestock*? what am I saying, of course they implemented gay livestock
<Iskierka>
either real or imaginary, R or I, RoI, clearly they're irish numbers
* Iskierka
runs
<UmbralRaptor>
egg: well, yes.
<UmbralRaptor>
Return on Investment
<soundnfury>
Iskierka: nombres du Roi... they're Leroy numbers!
<soundnfury>
(should that be du roi? I may have reflexively German-capitalised that noun)
<bofh>
egg: like the thing you're thinking of is just the direct product of Z2 and R, I just realized
<egg>
or I could call them Radicals
<egg>
bofh: well yes, but it has more structure
<bofh>
I feel like that's isomorphic to something nice but it's escaping me atm (SO(1,\mathbb{R})? no, that seems wrong)
<egg>
bofh: e.g. it's closed under trig functions and their inverses
<egg>
which is a funny thing to be
<bofh>
so what you're trying to say is that the exponential map is well-defined and a surjection
<egg>
bofh: nah I don't think that's quite equivalent (remember, not closed under addition, so can't express the trig functions as sums of exponentials)
<egg>
in fact the exponential most definitely isn't well-defined on the imaginaries, since that lands almost always outside this set
<egg>
UmbralRaptor: so should I stare at jupiter
<bofh>
egg: yes, but you're thinking of it as a group whereas I think it's more appropriate to consider this as a low-dimensional lie algebra
<bofh>
like the lie algebra of the circle group is just the imaginary line, for instance
<bofh>
(with the exponential map being the obvious one).
<egg>
bofh: so what is the corresponding Lie group here
<egg>
UmbralRaptor: moons!
<egg>
UmbralRaptor: bands!
<egg>
UmbralRaptor: chromatic aberration!
<bofh>
like I want to say O(2,\mathbb{R})
<egg>
uh
<bofh>
but unfortunately O(n,\mathbb{R}) only seems to decompose into SO(n,\mathbb{R}) x {±1} for *odd* n
<egg>
yes also hyperbolic angles are unbounded
<soundnfury>
egg: I still say they're "le RoI numbers"
<bofh>
which is really fucking frustrating since SO(2,\mathbb{R}) is isomorphic to S1, which--okay, yeah, we don't want compactness here. Right.
<UmbralRaptor>
egg: all moons on one side!
<soundnfury>
UmbralRaptor: wat? that's not allowed
<egg>
bofh: so if we want to separate the angles from the lines, we end up with a line stuck to a circle
<soundnfury>
it offends my aesthetic sensibilities
<bofh>
also I need a fast way to convert \mathbb{R} into ℝ when typing in, like, irc :P
<bofh>
egg: hm.
* UmbralRaptor
launches soundnfury into a distant retrograde orbit.
* soundnfury
resonantly pumps UmbralRaptor until it collides with Jupiter
<egg>
bofh: custom IRC client that does preprocessing
<egg>
bofh: also we need an IRC client that uses colour codes to send DF screenshots
<UmbralRaptor>
LaTeX rendering in an IRC client scares me for some reason.
<egg>
UmbralRaptor: yup, one is slightly above the line through the others though
<soundnfury>
egg: send patches, I would accept this feature in quIRC
<egg>
UmbralRaptor: Europa
<egg>
Io Ganymede Callisto pretty much aligned
<soundnfury>
after all, it's still less crazy than DCC (which I refuse to have)
<egg>
UmbralRaptor: should I use a filter to limit chromatic aberration
<egg>
UmbralRaptor: and if yes, which colour
<UmbralRaptor>
blue?
<soundnfury>
green, so it looks like jool?
<UmbralRaptor>
might increase belt/zone contrast.
<soundnfury>
only without a retrobop :(
<egg>
UmbralRaptor: ah good point (tried yellow, killed aberration alright, but very little contrast)
<egg>
(and I don't have green)
<soundnfury>
egg: use a Quality Street wrapper :P
<egg>
UmbralRaptor: hmmm the blue filter yields a very aberrant image
<soundnfury>
(that is the ISO Standard way to chromatically filter transmitted light)
<UmbralRaptor>
A green narrowband filter could be interesting for nebulae. (Hβ, OIII, etc)
* UmbralRaptor
pokes egg's scope in the chromatic abberation.
<soundnfury>
!wpn egg's scope
* Qboid
gives egg's scope a pythonic dynamorphism
<egg>
UmbralRaptor: yes but then I'd want a big cat rather than a finder I think
<egg>
UmbralRaptor: also if I combine the yellow and blue filter I do get a green filter, but that's much like the yellow one except darker for jovian porpoises
<egg>
UmbralRaptor: also the window is really dirty
<UmbralRaptor>
egg: They're more of flying mantas than porpoises, really.
<egg>
true
<bofh>
I love it when I try to do something really complicated in fontforge like, say, generating 10 bitmap glyphs from a TTF and then emitting a BDF, and I get a segfault in strchr() (*AFTER* it successfully appears to have created bitmaps, too!)
<egg>
bofh: hmm, so you're right, I can't seem to get a good formula for the function true anomaly -> time (suitably measured in ratios of adequate powers of μ and ℓ)
* Ellied
*finally* got around to changing her shell to zsh.
<Ellied>
no regrets at all, this is awesome.
<egg>
bofh: I mean, I can get a formula alright, but it involves things with horrible condition around e = 1
<egg>
(I can get the series there though, so I guess that's the way out)
<egg>
oh hey there was a Falcon 9 launch?
<egg>
we need a Kountdown...
<bofh>
this is idiotic, found a workaround and it involves going TTF -> bitmap TTF -> BDF (which then -> PCF)
<soundnfury>
egg: GTO injection still to come...
<bofh>
egg: oh? what is it?
<bofh>
soundnfury: what's the sat?
<soundnfury>
(about 3 minutes to go I think)
<soundnfury>
bofh: inmarsat-5 F4
<soundnfury>
over 6 tons, so s1 was expended :'(
* UmbralRaptor
has heard good things about zsh.
<egg>
p
<egg>
uh
<egg>
wat
<egg>
<bofh>
oh awesome, GTO successful!
<bofh>
also why the fuck was a geosynchronous comms sat so bloody heavy?