* Qboid
gives UmbralRaptor whitequark Iskierka a supercritical number
<egg|zzz|egg>
!wpn -add:adj ground
<Qboid>
egg|zzz|egg: Adjective added!
<egg|zzz|egg>
!wpn -add:wpn squirrel
<Qboid>
egg|zzz|egg: Weapon added!
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<Iskierka>
!wpn egg|phone|egg
* Qboid
gives egg|phone|egg a death sulfur polyhedron
<Iskierka>
punk band? I'm thinking punk band
<soundnfury>
!wpn egg|zzz|egg
* Qboid
gives egg|zzz|egg a moral polygon
<egg|zzz|egg>
!wpn Norgg
* Qboid
gives Norgg a Schwarzschild octagon
<Norgg>
!wpn -add:wpn Norgg
<Qboid>
Norgg: Weapon added!
<Norgg>
!wpn -add:adj eggy
<Qboid>
Norgg: Adjective already added!
<Norgg>
Of course.
<soundnfury>
!wpn -add:adj partially-ordered
<Qboid>
soundnfury: Adjective added!
<soundnfury>
!wpn -add:wpn supremum
<Qboid>
soundnfury: Weapon added!
<soundnfury>
!wpn -add:wpn infimum
<Qboid>
soundnfury: Weapon added!
<soundnfury>
!wpn -add:adj squeeze
<Qboid>
soundnfury: Adjective added!
<soundnfury>
!wpn
* Qboid
gives soundnfury a combustion ███████
<soundnfury>
!wpn -add:adj solenoidal
<Qboid>
soundnfury: Adjective added!
<soundnfury>
!wpn -add:adj irrotational
<Qboid>
soundnfury: Adjective already added!
<soundnfury>
!wpn -add:adj Helmholtz
<Qboid>
soundnfury: Adjective added!
<soundnfury>
!wpn
* Qboid
gives soundnfury a valid demon
<Iskierka>
if (demon.name != "Jesus"):
<soundnfury>
Iskierka: clearly the demon is Maxwell's
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Thomas|AWAY is now known as Thomas
<Thomas>
!wpn
* Qboid
gives Thomas a clopen blizzard
<egg|zzz|egg>
!wpn Thomas
* Qboid
gives Thomas a cathode ray tetrahedron
<bofh>
soundnfury: I'm partial to Laplace's, personally
<SnoopJeDi>
our department once had a softball team called Maxwell's Demons
<bofh>
achievement unlocked: spill coffee on self in meeting with advisor... ✓
<whitequark>
move coffee into self
* whitequark
mechanically licks fingers
* whitequark
remembers they just handled a broken LCD display
<SnoopJeDi>
mov coffee, eax
<bofh>
whitequark: yum, glass
<whitequark>
bofh: more thinking of the electrolyte here
<whitequark>
also I just got a wonderful smol hot plate (sadly I have no way to take a pic) and tried to use it to separate the digitizer and the LCD on an old xperia z2 display
<whitequark>
well it's interesting
<whitequark>
the glue is *incredible*
<bofh>
oh?
<whitequark>
but also the glass actually bends quite a bit
<whitequark>
so if it wasn't cracked in the first place, I think a slow and judicious application of a thin flat object between them would separate them
<whitequark>
and the display would come off in a flattish crescent shape from what I can see
<whitequark>
like maybe bent 5° from side to side
<bofh>
huh, interesting
<bofh>
a clopen blizzard sounds annoying
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<bofh>
at least it wasn't me compulsively singing Blind Guardian while nobody was looking this time
<bofh>
why is A Dark Passage so goddamn catchy
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<egg|zzz|egg>
o/ whitequark
<egg|zzz|egg>
!wpn whitequark
* Qboid
gives whitequark a visible reflector
<egg|zzz|egg>
also
<egg|zzz|egg>
!wpn bofh
* Qboid
gives bofh an optical contingent ? which strongly resembles an ordinal
<UmbralRaptor>
!wpn egg|zzz|egg
* Qboid
gives egg|zzz|egg an erbium arrow-like cardioid
<egg|zzz|egg>
!wpn UmbralRaptor
* Qboid
gives UmbralRaptor a moral asterism
<UmbralRaptor>
Stellar morality?
<egg|zzz|egg>
UmbralRaptor: whitequark got a reflector
<egg|zzz|egg>
I'm jealous
<UmbralRaptor>
20 cm?
<egg|zzz|egg>
dunno, Qboid didn't give the aperture
<egg|zzz|egg>
UmbralRaptor: also, I wonder whether we use 20 cm or 200 mm
<UmbralRaptor>
Bad bot!
<egg|zzz|egg>
I mean you americans use 8 inches, but you're nuts
<UmbralRaptor>
But those eyepiece diameters really are in inches!
<whitequark>
egg|zzz|egg: what
<whitequark>
reflector?!
<whitequark>
like in 'telescope'?
<whitequark>
oh
<whitequark>
Qboid:
<whitequark>
nevermind
<egg|zzz|egg>
whitequark: yes, I was talking about the Qboid output
<egg|zzz|egg>
good bot
* egg|zzz|egg
pets Qboid
<pizzaoverhead>
o/
<pizzaoverhead>
!wpn pizzaoverhead
* Qboid
gives pizzaoverhead a covariant amphibious line
<egg|zzz|egg>
*stares at backlog* UmbralRaptor, you want me to try out an OS? what's next, principia requiring its own OS?
<egg|zzz|egg>
nah, I think first we'll have principia requiring its own compiler, then its own language, then its own OS, then its own arch
<egg|zzz|egg>
clearly at that last stage whitequark is involved somehow
<pizzaoverhead>
No custom hardware?
<egg|zzz|egg>
principia the mod that requires an FPGA as a coprocessor
<whitequark>
sure
<Thomas>
principia, the mod that requires its own computational cluster
<UmbralRaptor>
egg|zzz|egg: Well, it was more of a name pun, but sure.
<UmbralRaptor>
Thomas: That way lies FORTRAN
<SnoopJeDi>
so I learned last night while reading a screed about Docker that NERSC's Docker-alike is actually very much in existence already
* egg|zzz|egg
forgets to pipe ls -lt into head half the time when looking at the principia log folder
<SnoopJeDi>
although it's less of a "Docker is insane let's build around that core idea" than it is "here's how to make your Docker images work on Cori and Edison"
<SnoopJeDi>
They claim VMs in general are a target, but it's not clear to what extent that's a "we want" instead of a "we have" feature
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<egg|zzz|egg>
whitequark: oh btw, I've been launching solids in KSP to test things recently, here's an example of a visible very old bug that's simple to fix and won't be: once you go fast enough, the smoke appears at fixed intervals in space behind the rocket, leaving a ..... trail behind it. The fix is a one-liner I wrote in a mod https://github.com/sarbian/SmokeScreen/pull/7/files#diff-719c82f22c6b6c0fa35c3fa22c5dd2a6R289
<egg|zzz|egg>
(took me two tries because krakensbane)
<kmath_>
<__the_sylph__> @whitequark the latin comment is bothering me more than the code tbh `// newton's third law` would have sufficed
<egg|nomz|egg>
the illuminated brains thing? or "me, an intellectual"
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<bofh>
so like honestly as far as latin goes I'm finding that very readable
<bofh>
<shrug>
<egg|nomz|egg>
bofh: it is, I mean, it's Newton's time, not Cato's
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<bofh>
well all I know of Cato is "...ceterum censeo Carthaginem esse delendam"
<GreeningGalaxy>
also, carthage must be destroyed?
<e_14159>
bofh: You might be a few centuries too late.
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<SnoopJeDi>
1) send email to developers asking for documentation of file format they developed but didn't document
<SnoopJeDi>
2) get bounced around a few times
<SnoopJeDi>
3) get undocumented utility script for creating said files from very specific other format, including https://hastebin.com/iduxofidew.cpp
<SnoopJeDi>
4) ???
<UmbralRaptor>
4) Painfully document the file yourself
<UmbralRaptor>
5) Submit a pull request or the like
<UmbralRaptor>
6) Get it rejected for bad reasons
<SnoopJeDi>
in fairness, the script is actually pretty clear
<SnoopJeDi>
but if you're going to create a specific HDF5 format for your code to use and not specify what the format *is*...
<bofh>
hey you got a tool for it and it wasn't binary-only
<bofh>
and moreover it wasn't uh
<SnoopJeDi>
(I should clarify that the script actually came from a non-developer who has to put up with their bullshit)
<bofh>
oh of course. those are always the people with the useful tools.
<UmbralRaptor>
Ow
<bofh>
oh found it
<bofh>
./bev/fbtoline: a.out SunOS mc68020 demand paged executable not stripped
<bofh>
(still not the worst I've had to deal with, but that's the worst I've had to deal with that wasn't by choie)
<bofh>
choice*
<SnoopJeDi>
I guess I'd be less angry if there was an example file showcasing each feature of the format
<SnoopJeDi>
At least then I could play identify-the-pattern instead of reading HDF5 reader/writer code
<bofh>
true.
<bofh>
hey, look on the bright side, at least it doesn't involve converting IBM floats to IEEE754 :P
<bofh>
(I've had to do that *disturbingly often*)
<egg|nomz|egg>
*ping*
egg|nomz|egg is now known as egg
* egg
pings on floating point talk :-p
<SnoopJeDi>
what about root beer float talk?
<egg>
that pings me, but that's probably a mistake
<egg>
does IEEE 754 talk about root beer
<UmbralRaptor>
Note to self: don't misread IBM as ICBM. Especially when floating point math is involved.
<SnoopJeDi>
sqrt(beer)
<soundnfury>
I was going to go with root beer finding algorithm, but meh
<bofh>
^
<bofh>
gradient descent or better?
<SnoopJeDi>
I've got an O(1) algorithm
<SnoopJeDi>
Go to [local bar]
<soundnfury>
bofh: newton, natch
<egg>
bofh: I think the only root finder we have in principia is a bisection
<egg>
dull, but does the job in bounded time :-p
<SnoopJeDi>
Actually, come to think of it, there are two places within spitting distance of each other that serve root beer on draught
<soundnfury>
egg: finding roots with the Tsurugi of Muramasa
<SnoopJeDi>
but only one of them serves it with Bailey's and a cherry :P
<egg>
bofh: ... today in big O being useless: bisection-to-the-ULP is O(1) :D
<UmbralRaptor>
soundnfury: stabbity?
<bofh>
egg: so I have way too many root finders. my favourite for 1-d is newton-with-aitken-extrapolation for general differentiable functions and laguerre's method for polynomials
<soundnfury>
UmbralRaptor: I think it's more a slashing weapon really
<egg>
bofh: maybe we'll add that in version Laguerre
<soundnfury>
probably can't punch through maille with its point
<egg>
if we get to that before we're dead :-p
<egg>
slow dev cycle is slow
<bofh>
also like there are so many french mathematicians whose names start with L
<bofh>
so I knew laguerre (and I guess laplace) but none of the others
<SnoopJeDi>
[distant joke about Newton and Pascal playing hide and seek]
<soundnfury>
bofh: ... leroy...
<soundnfury>
(accusing him of being French is fun!)
<soundnfury>
also, that one means the king?
<egg>
indeed
<egg>
old spelling, but it does
<egg>
(not *that* old, in the 18th century it's still spelled like that)
<soundnfury>
qu'ils mangent des oeufs?
<soundnfury>
or is your regime not that ancien?
<egg>
whitequark: oh, on the subject of "shoving maths into people", this thing you retweeted sounds like a good way to talk about symplecticity, I need to think about that a bit http://vf.rohanp.xyz/
<egg>
SnoopJeDi: yeah but that doesn't propagate an area of the phase space
<egg>
also that integrator was a bit shitty iirc
<SnoopJeDi>
yea it wasn't Verlet
<egg>
also gosh that vector field integraator isn't conservative
<SnoopJeDi>
the point about area is a good one
* SnoopJeDi
violates Liouville's theorem
* egg
stares at red screen
<SnoopJeDi>
I've always thought a web demo of the principles of accelerators would be fun
<SnoopJeDi>
But can't really grok how to make it not-super-boring
<egg>
SnoopJeDi: I've seen the phase space area thing with cat pictures
<egg>
cats on a phase space \o/
<SnoopJeDi>
it's a topic of great concern to simulation in our field since N_turns is measured in tens of thousands for even hum-drum machines
<SnoopJeDi>
well, that and the fact that the coupling force is so much stronger than gravity
<bofh>
> * SnoopJeDi violates Liouville's theorem
<bofh>
I object.
<soundnfury>
Sturm und Drang.
<SnoopJeDi>
bofh, the trick is to just be deliberately stubborn about what you call a system! \o/
<SnoopJeDi>
(accelerator lattice Hamiltonians are generally only considered in terms of bending and strong focusing, and you treat everything else as perturbations of some variety)
<SnoopJeDi>
but since the 6D volume ("emittance" in our jargon) is defined by that Hamiltonian, you can do Clever Things™ that you might not expect are possible if you've had your head buried in Courant-Snyder theory
<egg>
SnoopJeDi: do you also tend to typo Hamiltonion, or is that just me being french
<egg>
(but then should I not type Hamiltoignon? who knows)
<SnoopJeDi>
so far as I know I've never made that typo
<egg>
<whitequark> in C++ you can just do computations with constexpr <<< yes, something something UT1 to TT :D
* Qboid
gives GreeningGalaxy a signalling Hittite ristretto
<GreeningGalaxy>
!wpn |egg⟩
* Qboid
gives |egg⟩ a calcium isomorphism-like torpedo
<egg>
⟨egg|torpedoed|egg⟩
<GreeningGalaxy>
the eigenvectors of torpedoed are |thunk⟩ and |BOOM⟩
<Iskierka>
blah @ maths examples class and lack of context
* GreeningGalaxy
gives Iskierka an arbitrary context
<Iskierka>
less arbitrary would be more helpful
<bofh>
feels like that's a lot of maths classes.
* Iskierka
is unsure how to formally determine if the modulo equivalence classes of addition and multiplication have inverses. Or even if "determine" requires formality
* egg
is unsure how to parse Iskierka's question
<bofh>
same
<egg>
bofh: examples of sets: the empty set is a set; the union of two sets is a set; the intersection of two sets is a set; the singleton containing a set is a set.
<egg>
(arguably that's not so much examples as it is ~everything you do~ but :-p)
<Iskierka>
I logically think there's an inverse of addition since you can trivially loop back around but multiplication is less clear without definition to cleanly read
<egg>
additive is obvious, multiplicative is funnier
<Iskierka>
I think it may not as multiple entries in one equivalence class could divide to something else?
<Iskierka>
but also how do I do this formally, if I need to
<Iskierka>
in the modulo 4 equivalence class, [2] can be [1*2] or [3*2] (or commutatives), so trying to inverse with div 2 could be [1] or [3]
<Iskierka>
so I think no
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<Iskierka>
the table for modulo 4 multiplication does make a pretty pattern though
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<Iskierka>
0 0 0 0
<Iskierka>
0 1 2 3
<Iskierka>
0 2 0 2
<Iskierka>
0 3 2 1
<egg>
Iskierka: yup, but do note that 2*2=0; think about the implications for multiplicative inverses
<Iskierka>
that's another case of mixed inverses, but by contradiction I only need one to show that there isn't an inverse function
<Iskierka>
so [2] is an easy one since I can neatly avoid having to potentially skirt around div 0
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<Iskierka>
... now where the hell did 14 come from in this worked example
* Iskierka
starts throwing equation subsections at wolfram
<egg>
Ring mit Nullteiler
<egg>
!wpn GreeningGalaxy
* Qboid
gives GreeningGalaxy a venomous compression
<egg>
hmmm, we clearly need a !waffe command to produce things like Ring mit Nullteiler
<GreeningGalaxy>
!wpn egg
* Qboid
gives egg a spinlock
<egg>
whitequark: so, Cardano will have tilt; I gather you don't intend to use RSS? would you nevertheless like some tilted planets?
<whitequark>
egg: RSS?
<whitequark>
oh, realsolarsystem
<egg>
RSS?
<Qboid>
egg: [RSS] => Real Solar System
<whitequark>
mmm
<whitequark>
tilt sounds interesting
<whitequark>
wait, does stock ksp not have tilt
<Iskierka>
maybe the expander should be extended to identify questioning specific people
<Iskierka>
stock KSP doesn't allow planets to be anything other than universe-up axis
<egg>
(that won't be in the default, the default will just have retrobop, but I can make a config for you, since I need one to test that tilt works)
<egg>
(the default needs retrobop to prevent the apocalypse of course)
<egg>
whitequark: as Iskierka says, stock has all axes parallel
<whitequark>
*nod*
<whitequark>
sure that would be neat
<egg>
and that's hardwired quite deep in the game, so we tilt by tilting the universe, keeping the main body vertical :D
<egg>
(the map view bodies can be tilted, the body that has terrain cannot)
<egg>
we also move the universe around the ship, there's a lot of that when fighting KSP
<egg>
whitequark: what should I tilt?
<whitequark>
mmm
<whitequark>
duna?
<egg>
Ok
<egg>
do you want Kerbin tilt (and thus Kerbin seasons), or not
<whitequark>
that wouldn't actually add any seasoning would it?
<Iskierka>
need LoL players for that
<egg>
well, it wouldn't make the grass change colour or the weather change, but it would give changes to the length of day
<whitequark>
ooh, neat
<whitequark>
then I do
<whitequark>
does that function correctly with the "warp to next morning" feature etc
<egg>
whitequark: ... except the space centre is at the equator actually
<Iskierka>
except not significantly at KSC?
<whitequark>
oh right
<egg>
whitequark: oh, I'm not sure how that all meshes with the warp to next morning, that's a good question
<egg>
Iskierka: yeah, just realized that :-p
<soundnfury>
mmmmmmmm,
<soundnfury>
bacon.
<Iskierka>
presumably "next morning" is just to a fixed time of day
<egg>
yeah I'd assume KSP to be dumb
<egg>
warp to apoapsis etc. don't work, we have our own warp to next manoeuvre in the flight plan
<egg>
(the flight plan UI is kind of clumsy, but it's possible to use it :-p)
<egg>
...
<egg>
if (Sun.Instance == null)
<egg>
{
<egg>
Debug.LogError("Cannot time warp to next morning, because there is no sun!");
<egg>
return;
<egg>
}
<whitequark>
LOL
<egg>
I mean, sure, but if that's the case half the game will have broken
<Iskierka>
... what on earth is the case they're trying to deal with?
<whitequark>
what on kerbin?
<GreeningGalaxy>
tsk. my classical mechanics class has us talking only about prograde/retrograde apsis maneuvers and nothing else
<GreeningGalaxy>
I asked the prof if I might do my final paper over plane changes and he looked at me like I was stupid and asked me if I'd actually read the chapter
<Iskierka>
o.O
<GreeningGalaxy>
(I ultimately did my paper about 1/2 what was in the book and 1/2 my own derivations for phase-change maneuvers)
<GreeningGalaxy>
not sure if I want to bother getting into plane changes, it's due tomorrow at noon
<egg>
whitequark: so, I'm not sure whether the "warp to next morning" will work *even without tilt* given that we are the ones rotating the bodies; I might need to stab that feature into submission
<egg>
whitequark: although it won't affect KSC much, at least with tilt your polar drones will notice the change in length of day :-p
<UmbralRaptor>
Does warp until morning include atmospheric refraction?
<egg>
UmbralRaptor: I don't think that's implemented unless you use scatterer?
<kmath_>
<whitequark> TIL the viscosity of water changes by over a factor of five when heated from 0°C to 100°C¹, which is why it sounds… https://t.co/2zKKSI7bsd
<Iskierka>
slightly misleading graph though :p
<Iskierka>
also explains why you get splashed with hot water so much more easily than cold, though
<egg>
also visible: the density maximum which is always fun
<egg>
and iirc the original definition of the kg?
<whitequark>
the graph is annoying but I was too lazy to make my own
<egg>
I think they had come up with 1 l of water at its density maximum
<egg>
yup
<egg>
in 1799
<egg>
in 1795 they wanted to do it at the freezing point but that turned out not to be convenient