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.
<Fiora>
i also heard rumors from the grapevine that intel was transitioning to an llvm-based compiler
<Fiora>
a *lot* of companies have quietly switched to llvm
<Fiora>
qualcomm uses it for their middle-end on GPU
<Fiora>
AMD is quietly switching their entire stack over to a full LLVM middle/backend
<Fiora>
i'm fairly sure nvidia uses an LLVM middle-end
<bofh>
Yeah, but I'm kinda surprised Intel did, kinda expected them to maintain their own thing just to be different / for vendor lock-in purposes.
<Fiora>
well, they're still using their own backend
<Fiora>
intel is a bit of a weird duck when it comes to compilers though
<Fiora>
they are notorious for having way too many people (like, 1000) working on their compiler, to the point where people barely-jokingly say that each person has their own chunk of SPEC code they're responsible for
<Fiora>
it's terribly inefficient, deeply legacy, and well, you can imagine it's not great.
<bofh>
The hilarious thing is that ifort is a completely different codebase from icc, it's based off the old decfort90 code.
<bofh>
Which explains why ifort generates good code but f2c followed by icc generates utter trash even after you add *restrict everywhere.
<bofh>
(May not be true anymore, but was true as of 2015 still)
<Fiora>
you, a fool: C is a low level language that generates well-optimized code
<bofh>
But yeah, "deeply legacy in a way that rivals the worst of gcc" is the impression I got from icc.
<Fiora>
me, wise: fortran is good because it doesn't have pointers
<bofh>
So I use Fortran all the time, I just wanted to know why the heck the two generated wildly different code out of curiosity. I agree with you on this one in actuality.
<egg>
Ada is good because it is erroneous to rely on whether an argument is passed by copy or by reference
<bofh>
Fortran passes everything by reference, which is mildly annoying 5% of the time and incredibly handy the rest.
<Fiora>
cosmic brain: ISPC is good because none of your output data elements should have interdependencies anyways.
<bofh>
oh man that time I quickly hacked up llvm so that the cmdline switch to opt that makes it assume any pointers "may" alias instead makes it assume that any pointers "WILL NOT" alias and suddenly it autovectorized almost all float ops in random code I chucked at it.
<bofh>
(ofc said code unsurprisingly broke often, b/c data interdependencies sadly exist in reality)
<egg>
[disclosure: my father was chairman of the ARG during the standardization of Ada 2005, so it's the second language I learned (after VB6), and I rather like some aspects of it]
<egg>
bofh: oh, there is such an option?
<egg>
hmm
<egg>
bofh: relatedly, Ada is good because if something is aliased it says so in the type :-p
<bofh>
there is not in stock llvm, this was just me testing something out of curiosity.
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<bofh>
Ada is nice, just nobody really seems to know it outside of certain problem domains so I never had an opportunity to learn it.
<bofh>
(Fortran is much the same way except in that case I *did* intersect at least one (tbh the only) problem domains it's used in)
<bofh>
+of the*
<egg>
bofh: the type system isn't powerful enough though
<bofh>
Heh, in my case my first lang was actually QBASIC.
<bofh>
I did a bit of VB6 but barely any.
<egg>
bofh: so like VB6 was when I was maybe 8, so, it's not like I wrote anything actually interesting :-p
<bofh>
same here :P
<bofh>
I did hardly any real coding until like 11 years from then tho.
<egg>
bofh: yeah sadly I can't figure out a way to make the label in PlotMethod2 non-ascii
* bofh
shakes head at egg :P
<egg>
bofh: oooh, instead of nondescript "error estimate" I could clarify my identifiers, it's actually tan² of the angle, and then I can goto estimate_tan²
<egg>
styleguide: "goto is fine, but the label must not be ascii" :-p
<Fiora>
oh another fun thing about autovectorization
<Fiora>
because reductions/ordering matter, it can be close to impossible to autovectorize with fast math off
<bofh>
Yep.
<Fiora>
also float autovectorization is, by comparison, incredibly easy
<Fiora>
integer is way harder because the compiler doesn't know the intermediate ranges of your values!
<Fiora>
and C of course completely obscures them.
<bofh>
Yeah, I'm only talking about float autovectorization since that's all I've cared about. Integer autovec sounds like a goddamn nightmare.
<egg>
something something Ada integer subtypes something :-p
<Fiora>
what does Ada do with intermediate values in expressions?
<Fiora>
ex
<egg>
they're in the base type
<Fiora>
<type> X = a + b * d - c
<Fiora>
given a ,b, d, c have types A, B, C, D
<Fiora>
what are the intermediate types of that expression?
<egg>
1 min
<egg>
Fiora: okay, so, in order for that expression to be legal (since you wrote no conversions), A, B, C, and D have to be subtypes of one same type. Intermediate expressions are in the base type of that type (A'Base, which is B'Base etc.)
<Fiora>
are they promoted to the highest possible base type? or the one that's closest to those types?
<egg>
Fiora: nevermind, they may be wider (implementation-defined), see RM05 3.5 paragraph 6: "The base range of a scalar type is the range of finite values of the type that can be represented in every unconstrained object of the type; it is also the range supported at a minimum for intermediate values during the evaluation of expressions involving predefined operators of the type."
<Fiora>
.............. oh
<Fiora>
welp
<egg>
also paragraph 15: S'Base denotes an unconstrained subtype of the type of S. This unconstrained subtype is called the base subtype of the type.
<egg>
I think there are guarantees on the base type, lemme dig further
<Fiora>
i was thinking like
<Fiora>
(sorry for the horrible java typing metaphor --)
<Fiora>
fish are animals, sharks are fish
<Fiora>
is a shark * salmon promoted to fish or promoted to animal
<egg>
Fiora: aha: RM05 3.5.4 paragraph 9: A signed_integer_type_definition defines an integer type whose base range includes at least the values of the simple_expressions and is symmetric about zero, excepting possibly an extra negative value. A signed_integer_type_definition also defines a constrained first subtype of the type, with a range whose bounds are given by the values of the simple_expressions, converted to the type
<egg>
being defined.
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<egg>
Fiora: so, for your example
<Fiora>
this sounds potentially worse than C, where you can at least define your intermediates to have specific sizes?
<egg>
type Animal is range 1 .. 42; subtype Fish is Animal range 2 .. 30; subtype Shark is Fish range 10 .. 20;
<egg>
F : Fish; S : Shark;
<egg>
F * S, per se, doesn't have a type; it is evaluated in the base range, so at least in -42 .. 42
<egg>
now, if you assign it to an Animal, it will be range-checked as such
<Fiora>
ahhhh
<egg>
if you assign it to a Fish, it will be range-checked as such
<egg>
you might even assign it to a Shark I think
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<egg>
Fiora: expressions don't necessarily have types, Ada has return type overloading
<Fiora>
is that like type inference?
<egg>
Fiora: well, it's just that if there's an F that takes a Long_Float and returns a Float and another that takes a Long_Float and returns a Long_Float, if I say X : Float := F(1.0); it will call the former
<egg>
Fiora: note: the literal 1.0 doesn't have either type; it's a Universal_Real (compile-time arbitrary precision rational)
<Fiora>
oh fun
<egg>
Fiora: so your shark example: shark * fish can be assigned to shark, it may fail the range check too but that's your problem https://ideone.com/y0K2EH
<egg>
(I should have initialized those variables, this is a bounded error)
<egg>
Fiora: so this is actually a bounded error, not UB: S and F are guaranteed to have values of their base types
<egg>
this was introduced in Ada 95 because people realized UB ("the program is erroneous" is the Ada term) for uninitialized variables was a mess
<egg>
so instead you get bounded error, which is well-defined
<egg>
Fiora: note that they are all the same *type* (so likely the same memory representation), just different subtypes (constraints); you can't do things between different types without an explicit conversion
<egg>
Fiora: e.g. here, I have to say Plant(F), because Plant and Fish have different types (potentially with different base ranges, maybe the compiler has decided to put Plant on 53 bits and Animal on 24 https://ideone.com/bX9TMJ)
<Fiora>
huh
<Fiora>
makes sense
<egg>
so the explicit conversion tells us which base range will be used (otherwise I could do Animal(P) * F)
<egg>
and then the assignment does the range check
<egg>
Fiora: if you need to know the base range, you can use a representation clause, type Natural_32 is range 0 .. 2 ** 32 - 1; for Natural_32'Size use 32;
<egg>
then you know that the thing is 32 bits, and that its base range includes 0 .. 2 ** 32 - 1 and is symmetric around 0, so its base range is a signed int32
<egg>
(and you can also make a 53-bit integer like that, though the code emitted probably isn't going to be pretty)
<Iskierka>
... I was going to link a twitter post then remembered Fiora is here now. NFPA Yahtzee is fun
<Fiora>
this is actually my first NFPA yahtzee from randomly looking at chemicals on wikipedia
<Fiora>
also that chemical structure is so great.
<Iskierka>
this totally needs to be a proper game
<egg>
*wonders where he already heard of pentaborane* ooooh right. RealSolarSystem/RealismOverhaul/RealFuels...
<Iskierka>
You can blame rocketry for a lot of fun chemicals. If they're not in realfuels I'm sure Ignition! has at least a paragraph
<egg>
Fiora: oh fun, 3.5.4:24: For the execution of a predefined operation of a signed integer type, the implementation need not raise Constraint_Error if the result is outside the base range of the type, so long as the correct result is produced.
<Iskierka>
... how does it produce a correct result if it's outside the range?
<egg>
so if the compiler writer feels like it they can do the intermediate calculations in a wider type (but they have to check the overflow bits, because the correct result must be produced)
<UmbralRaptor>
Incidentally, Monomethyl hydrazine is also 444.
<Iskierka>
somehow UDMH is only 431
<Fiora>
wasn't part of the -purpose- of UDMH making something that wasn't a 4in the last digit?
<Fiora>
i.e. didn't explode when breathed on
<egg>
I thought it was about not freezing?
<Fiora>
i mean, both
<Iskierka>
it still produces NDMA which doesn't even have a NFPA set, presumably because the answer is "no"
<Iskierka>
peroxide at 302 confuses me. Mainly that how is an intensive oxidizer 0 fire hazard
<Iskierka>
if it's that it decays too fast and violently with itself, how is it only 2 for instability
<Fiora>
fire hazard is about ignition iirc
<Fiora>
hydrogen peroxide literally doesn't burn
<Fiora>
if it doesn't have a flash point it's 0 iirc
<Iskierka>
... in the same way oxygen doesn't?
<Fiora>
like, iirc fire hazard is about the ability to burn given an oxidizer
<Fiora>
oxidizers themselves have their own category (the OX)
<Iskierka>
seems to me like you should probably still note intensity in the fire part
<Iskierka>
the OX can then just represent that you need to give it something else rather than keep air away from it
<Fiora>
well by that definition air is a huge fire hazard
<UmbralRaptor>
Air is a huge fire hazard!
<UmbralRaptor>
Just look at what it does to metallic dust!
<UmbralRaptor>
Good luck sleeping, Iskierka && egg
<Iskierka>
I am disappointed that the wiki article doesn't quote an efficiency for pentaborane-nitrogen tetroxide
<Iskierka>
I shall have to see if RPA has data for them and can guesstimate tomorrow
<ferram4>
Iskierka, it does.
<ferram4>
It also has OF2 and ClF3. But not FOOF, unfortunately.
<Iskierka>
Oh yes, I remember searching for that
<Iskierka>
though it does have ozone, which is ... impressive
<Iskierka>
too bad it caused the test stands to learn a magic trick
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<egg|work|egg>
!wpn Thomas
* Qboid
gives Thomas an overclocked groupoid
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<egg|work|egg>
!wpn bofh
* Qboid
gives bofh an aluminium geobukseon
<egg|work|egg>
!wpn Fiora
* Qboid
gives Fiora a bipolar junction gegenschein
<UmbralRaptor>
!wpn egg|work|egg
* Qboid
gives egg|work|egg a caffeinated ☣-like type
<egg|work|egg>
!wpn UmbralRaptor
* Qboid
gives UmbralRaptor a dynamo with a nephroid attachment
<egg|work|egg>
!wpn ☣
* Qboid
gives ☣ a voltage-gated torch
<egg|work|egg>
um
<egg|work|egg>
!u ☣
<Qboid>
U+2623 BIOHAZARD SIGN (☣)
<UmbralRaptor>
?? torch (?) or ?? torch (?)
<UmbralRaptor>
?
<egg|work|egg>
!u ?? torch (?) or ??
<egg|work|egg>
uh
<egg|work|egg>
ah thankfully there was a prefix space
<egg|work|egg>
!u ????
<Qboid>
U+1F1EC REGIONAL INDICATOR SYMBOL LETTER G (?)
<Qboid>
U+1F1E7 REGIONAL INDICATOR SYMBOL LETTER B (?)
<Qboid>
U+1F1FA REGIONAL INDICATOR SYMBOL LETTER U (?)
<Qboid>
U+1F1F8 REGIONAL INDICATOR SYMBOL LETTER S (?)
<egg|work|egg>
ah
<egg|work|egg>
Thomas: can you subscribe this channel to Qboid's kountdown?
<Thomas>
!kountdown -subscribe:#kspacademia
<Qboid>
Thomas: Added the channel to the Kountdown subscribers.
<bofh>
huh, apparently tert-butyl mercaptan was on the EFSA's flavour list once.
<bofh>
quote: "There is no indication of what flavor(s) in which it may have been used. It has been removed from this list.[11]
<bofh>
+"*
<egg|work|egg>
bofh: ...
<egg|work|egg>
bofh: also, we have a kountdown now!
<bofh>
oh awesome
<bofh>
does it have the Markov feature too?
<bofh>
rofl a voltage-gated torch
<UmbralRaptor>
Tastes like exploding death?
<bofh>
UmbralRaptor: actually, essence of skunk spray
<bofh>
"Even in well ventilated areas, extreme caution must be made when handling tert-butylthiol as it is a highly odorous chemical with an odor threshold of <0.33 ppb. Extreme caution is not due to toxicity, but due to the significant odor and the concern this odor could cause to individuals that might be exposed. The PEL for thiols of most types is 500 ppb, primarily due to reaction of nausea at levels of
<bofh>
2–3 ppm."
<bofh>
!u –
<Qboid>
U+2013 EN DASH (–)
<egg|work|egg>
bofh: nah just the kountdown afaik
<egg|work|egg>
!kountdown -help
<Qboid>
egg|work|egg: Invalid ID!
<egg|work|egg>
!help kountdown
<Qboid>
kountdown: Prints out the details for Kountdown Events
<Qboid>
parameters: -add (Add Kountdown event. Syntax: !kountdown -add name|description|time.), -list (List pending Kountdown Events or subscribers), -remove (Delete Kountdown by id.), -edit (Edits a Kountdown by id.), -subscribe (Subscribe yourself or a channel to Kountdown.), -unsubscribe (Unsubscribes yourself or a channel from the Kountdown.)
<Qboid>
example: !kountdown 1
<egg|work|egg>
bofh: ^
<bofh>
Ahh.
<bofh>
Convenient. When's the next launch?
<bofh>
Okay, there's an Aug 14th one of NROL-42 from Vandenburg, Aug 13th is SpaceX Dragon from Kennedy
<egg|work|egg>
bofh: I added the japanese one
<egg|work|egg>
Thomas: feature request: next launch :-p
<bofh>
^
<egg|work|egg>
bofh: or rather I had Thomas add the japanese one because I'm not nickserved here
<bofh>
ns group, silly :P
<bofh>
or whatever that command is on this network
<egg|work|egg>
bofh: I don't have an actual client
<egg|work|egg>
so I'm just not signed in to nickserv
<egg|work|egg>
I'm on webchat here
<bofh>
ahh.
<Thomas>
!kd next
<Qboid>
Thomas: Invalid ID!
<Thomas>
Moo
<Thomas>
!kd next
<Qboid>
Thomas: Order By does not support: e => e.Time.Ticks
<Qboid>
Thomas: Description: A Japanese H-2A rocket, designated H-2A F35, will launch the Michibiki 3 navigation spacecraft, the third member of Japan’s Quasi-Zenith Satellite System.
<Thomas>
egg|work|egg: ^
<egg|work|egg>
Thomas: um, please set your current culture to something sane
<egg|work|egg>
or the date format
<egg|work|egg>
because I'm pretty sure it doesn't launch in november
<Thomas>
egg|work|egg: Would this be acceptable for you? "2017-26-04 05:26:10"
<Qboid>
Thomas: Description: A Japanese H-2A rocket, designated H-2A F35, will launch the Michibiki 3 navigation spacecraft, the third member of Japan’s Quasi-Zenith Satellite System.
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<egg|work|egg>
Thomas: yes, that's good
<egg|work|egg>
I don't require the T of ISO 8601 :-p
<egg|work|egg>
Thomas: um
<egg|work|egg>
Thomas: that's good except the 0th month is wrong
<egg|work|egg>
Thomas: you might have put minutes there instead of months
<egg|work|egg>
Thomas: also the 26th month is wrong for the same reason :-p
<Qboid>
Thomas: Description: A Japanese H-2A rocket, designated H-2A F35, will launch the Michibiki 3 navigation spacecraft, the third member of Japan’s Quasi-Zenith Satellite System.
<egg|work|egg>
Thomas: that looks good; I'd grump about the "m" instead of the standard "min" in the time left but that's not ambiguous
<egg|work|egg>
well that's assuming it's units though; there's the horrendous ISO 8601 way of writing durations but it's just ugly :-p
* egg|work|egg
heads back home
<UmbralRaptor>
!wpn egg
* Qboid
gives egg a soldering ideal pharmacology/trie hybrid
<bofh>
!wpn egg
* Qboid
gives egg a depressurized underflow
<bofh>
ahh, my favourite type of underflow.
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<egg|phone|egg>
!wpn UmbralRaptor bofh Fiora
* Qboid
gives UmbralRaptor bofh Fiora an isothermal rake
<UmbralRaptor>
Compression, expansion, raking
<bofh>
Obv.
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<TonyC>
hi does anyone play Aurora 4x here ?
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<ber>
THE NEWEST AND HOTTEST IRC IN ALL OF TORLAND
<UmbralRaptor>
Did the server ops already kill it?
<Technicalfool>
who wants to do the honours and join #dragonweyr?
<SnoopJeDi>
they're disconnected now at any rate UmbralRaptor
<SilverFox>
wtf was I pinged in here for
<Technicalfool>
a bot. A bot is why.
<UmbralRaptor>
Technicalfool: I nominate you.
<lamont>
wat?
* xShadowx
seconds that nomination
<egg|zzz|egg>
+1
egg|zzz|egg is now known as egg
<SilverFox>
+1
<lamont>
does someone like DDoS attacks, ‘cuz that’s how you attract DDoS attacks…
* UmbralRaptor
stabs City Utilities. Apparently a # in an address makes it invalid.
<SnoopJeDi>
Do you have <10 lines of scrollback? o.O
<egg>
UmbralRaptor: speaking of foxes, saw one crossing the street this evening
<UmbralRaptor>
Fluffeh, Silver, or other?
<SnoopJeDi>
well I guess that's not all that unusual actually, my 18x24 usually has fewer than 10 lines.
* TonyC
puts a LOIC in low orbit
<egg>
UmbralRaptor: not sure if really fluffy, but definitely not silver
<SnoopJeDi>
TonyC, it'd be a bit bizarre of a LOIC was in any other orbit :P
<TonyC>
SnoopJeDi, indeed it would
<egg>
bofh: still no reply from the numerical cat :-\
<Technicalfool>
given the guy was likely to have come in from a tor exit node, DOSing it would not help.
<TonyC>
Part of me wants to run that link haha
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* UmbralRaptor
has questions, given that irssi seems to trivially fit 40+ lines on a 1280x800 monitor.
<SnoopJeDi>
I usually keep my IRC KiTTY at 18x24 UmbralRaptor and roughly the same shape if it's a tmux pane
<SnoopJeDi>
not that any of that matters since scrolling is...a thing that exists (and /lastlog and hilight.pl)
* UmbralRaptor
likes having half the screen as IRC and half as web when Silbervogel was working. (1920x1200 monitor)
<SnoopJeDi>
I'm atrocious at task organization :/
<egg>
UmbralRaptor: at work I have half of one of my 2 screens with webchat
<e_14159>
Wait, was that nick order randommized?
<bofh>
egg: sec let me poke
<SnoopJeDi>
the fact that I've been able to be consistent with pomodoros lately is a minor miracle
<UmbralRaptor>
TomatoJedi
<SnoopJeDi>
e_14159, looks similar to what I get from /who but I dunno how stable that is?
<egg>
!kountdown -add:Falcon 9 • SpaceX CRS 12|A SpaceX Falcon 9 rocket will launch the 14th Dragon spacecraft on the 12th operational cargo delivery mission to the International Space Station.|2017-08-13T16:57Z
<Qboid>
egg: Constraint
<egg>
Thomas: um
<bofh>
um
<Thomas>
Not -add:<text> but -add <text>
<egg>
ach
<Thomas>
Dunno why it does that though
<egg>
!kountdown -add Falcon 9 • SpaceX CRS 12|A SpaceX Falcon 9 rocket will launch the 14th Dragon spacecraft on the 12th operational cargo delivery mission to the International Space Station.|2017-08-13T16:57Z
<Qboid>
Thomas: Description: A SpaceX Falcon 9 rocket will launch the 14th Dragon spacecraft on the 12th operational cargo delivery mission to the International Space Station.
<Thomas>
egg|work|egg: now it worked
* Thomas
had forgotten to mark his index as autoincrement... dammn SQL
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<egg>
!kd -add Atlas 5 • TDRS M|A United Launch Alliance Atlas 5 rocket, designated AV-074, will launch the TDRS M communications and data relay satellite for NASA. The Tracking and Data Relay Satellite System (TDRSS) connects mission control with the International Space Station and other orbiting satellites. The rocket will fly in the 401 vehicle configuration with a four-meter fairing, no solid rocket boosters and
<egg>
a single-engine Centaur upper stage.|2017-08-18T12:04Z
<Qboid>
egg: Invalid syntax. The correct syntax would be name|description|time.
<egg>
!kd -add Atlas 5 • TDRS M|A United Launch Alliance Atlas 5 rocket, designated AV-074, will launch the TDRS M communications and data relay satellite for NASA.|2017-08-18T12:04Z
<Qboid>
egg: Added event #2
<egg>
!acr -add:TDRS Tracking and Data Relay Satellite System
<Qboid>
egg: I added the explanation for this acronym.
<Fiora>
arylsulfur pentafluorides are apparently relatively stable
<bofh>
Huh. Interesting.
<Fiora>
"henylsulfur
<Fiora>
pentafluoride is a colorless liquid, b.p. 149'
<Fiora>
and density 1.49 g./ml. It has a pleasant aromatic
<Fiora>
odor, unlike that usually observed with aromatic
<Fiora>
sulfur compounds, and it is soluble in common
<Fiora>
organic solvents, including pentane. The compound
<Fiora>
has chemical and thermal stability comparable
<Fiora>
to benzotrifluoride. "
<Fiora>
*Phenylsulfur
<bofh>
Huh, that's impressive.
<bofh>
Doubly so for smelling nice, considering thiophenol in comparison smells like the Platonic Ideal of Essence of Burnt Rubber
<Fiora>
it's toxic and burns but it's stable
<UmbralRaptor>
yay
<bofh>
(have smelled thiophenol briefly at like prolly 1ppm or so, no fucking thanks)
<Fiora>
wtf
<Fiora>
wikipedia claims butyric acid has an odor threshold of 10 ppm
<Fiora>
lots of papers claim 0.001ppm???
<Fiora>
yet another company's data ssheet says 300 ppm (I don't beleive this)
<bofh>
10ppm seems crazy high for butyric acid, pretty sure that one's smellable at ppb thresholds, at least that's what I've always seen.
<bofh>
300ppm LOL NO
<bofh>
have those people ever had butter go rancid? apparently not
<Fiora>
OH. I think I know what it is.
<Fiora>
one paper says 0.001 mg/m^3
<Fiora>
some of these are reporting density in *volume*, others are reporting in *mass*
<Fiora>
0.001 mg/m^3 is roughly 1 ppb by *mass*
<Fiora>
because air is ~1.2 kg/m^3
<bofh>
Ahh. Okay that makes sense.
<Fiora>
but the density of butyric acid is 960kg/m^3
<bofh>
Yep.
<Fiora>
they could also be going by mole fraction???
<bofh>
"The difference is quite significant when dealing with gases and it is very important to specify which quantity is being used. For example, the conversion factor between a mass fraction of 1 ppb and a mole fraction of 1 ppb is about 4.7 for the greenhouse gas CFC-11 in air. For volume fraction, the suffix "V" or "v" is sometimes appended to the parts-per notation (e.g., ppmV, ppbv, pptv).[9][10]
<bofh>
Unfortunately, ppbv and pptv are also often used for ...
<bofh>
... mole fractions (which is identical to volume fraction only for ideal gases).
<bofh>
+"*
<bofh>
great so units continue to be a goddamned tire fire
<bofh>
(swear in moments like these some disembodied voice goes "International British Thermal Units" in my head)
icefire has joined #kspacademia
<Fiora>
I hate it when people use the same units to mean entirely different things goddamn
<bofh>
Same. Like, this is outright hazardous honestly.
<bofh>
Since 1ppm mass fraction and 1ppm volume fraction as you just saw can be, erm, extremely different concentrations.
<Fiora>
the reason butyric acid came up is how i determined the other day that printing with polyvinyl butyral was almost surely safe
<Fiora>
because if it *did* decompose during printing even in the slightest, I would smell the butyric acid from the other side of the state
<bofh>
mostly for the horrendously vague sentence of "It is capable of producing a range of elements when heated, such as diborane, tetraborane, hydrogen."
<UmbralRaptor>
Messier 4 if you are in dark skies. (It has poor surface brightness)
<UmbralRaptor>
In Sgr proper, there's M8 (The "whisp of steam" coming out of the teapot), and M, uh, 15? just west of the top of the lid, and sorta bracketed by stars.
<egg>
UmbralRaptor: lower RAs and higher decls please
<UmbralRaptor>
Ah, 22, not 15.
<egg>
M6 is at alt 8
<UmbralRaptor>
Uh, M5?
<egg>
UmbralRaptor: M22 might do, but right under that pesky satellite of ours
<UmbralRaptor>
Dec-wise, there's a lot of stuff just north of the teapot. But moon...
<egg>
UmbralRaptor: M5 is, um, in a roof/tree/whatever also that's serpens
<egg>
UmbralRaptor: yeah I might as well just look at the moon I guess
* egg
looks for the ND filter
<UmbralRaptor>
Hrm. Maybe we should be going for something like Cygnus (M29, M39), Hercules (M13, 92), Lyra (M56, M57), or the like?
<UmbralRaptor>
Oh, right. There's that coathanger somewhere around there.
<UmbralRaptor>
It's in the fox!
<UmbralRaptor>
Er, wait. possum?
<UmbralRaptor>
Latin is a confusing language.
<egg>
UmbralRaptor: um so, sure but that'd require going out
<egg>
or hadrosaurs
* UmbralRaptor
grabs earplugs.
<egg>
I pretty much have Sgr out the window and that's it
<egg>
welp might as well look at the moon I guess
<egg>
gah an entire moon in 80 mm of aperture is bright even with the ndf
<UmbralRaptor>
What if we used more power?
<UmbralRaptor>
(No, seriously. It's dimmer at higher magnification.
<UmbralRaptor>
)
<egg>
UmbralRaptor: makes sense; short focal though so at the greatest mag I think I need a colour filter otherwise aberration kills me
<UmbralRaptor>
blarg
<egg>
red or blue? :-p
* egg
tries the 2.5 mm in blue
<UmbralRaptor>
I-band
<egg>
UmbralRaptor: mind you the entire moon still fits in the field with the 2.5 mm :D
<UmbralRaptor>
o_O
<egg>
(120x)
* UmbralRaptor
wants to say that the entire moon only fits with the 18 mm (50x), but not quite with the 12.7 mm (71x) with NAFOscope.
<UmbralRaptor>
Apparently if you let a checking account get low (not negative, just low), it becomes impossible to debit anything to it?
<Ellied>
wat
<Ellied>
Iskierka: why are snakes being kept in drawers
* UmbralRaptor
has a bit over $25 left in it. But...
<Iskierka>
snake library
<UmbralRaptor>
I just need a $1 charge with USPS for an account where my billing and residential addresses match up. >_<
<egg>
UmbralRaptor: M22 seems to be either in a tree or washed out by the bright sky
<egg>
or both
<UmbralRaptor>
egg: It's hanging from the try while we dry it out.
<Ellied>
UmbralRaptor: Find a bank that doesn't try to pull shit?
<UmbralRaptor>
Ellied: Yeah. I was planning on ditching this account anyway, after moving. They're a bit too local to be useful outside of southwest Misery.
<Ellied>
I'm often astounded by the crap banks can get away with
<UmbralRaptor>
Ellied: Also, I don't think I saw that sign before. Hah!
<Ellied>
the advanced photons are all inside
<UmbralRaptor>
Lobbies would be closed since it's after 5. Maybe I can head in tomorrow and complain at them?
<egg>
UmbralRaptor: is M75 usually visible in shitty skies?
<UmbralRaptor>
Oh, hey. They talk up HSAs on their website. Because of course they would.
* UmbralRaptor
stabbity.
<Ellied>
If I ran the show, banks would be fined for being late sending deposits through, let alone refusing you access to your account for arbitrary reasons or (as happened to me recently) doing the first thing and charging fees to the account for being negative in the meantime.
<UmbralRaptor>
egg: I don't think so?
<egg>
hm
<UmbralRaptor>
Make that no idea.
<UmbralRaptor>
I'm not so good with the Capricornus area.
<egg>
M30?
<Ellied>
(always fascinating how they manage to propagate withdrawals in milliseconds but can't seem to get deposits through within three days if it happens to be the weekend?)
<UmbralRaptor>
I'm under the impression that M30 is not great.
<egg>
yeah and by the time that's in the window the clouds might be there too
* UmbralRaptor
wants to say that the withdrawals aren't completely real. Something about holds?
<egg>
here payments get executed the next working day
<egg>
!wpn UmbralRaptor
* Qboid
gives UmbralRaptor a zircon magma
<UmbralRaptor>
"download your first time homebuying guide"
<UmbralRaptor>
...
<UmbralRaptor>
Maybe they just assume most millenials are unbanked?
<UmbralRaptor>
!wpn egg
* Qboid
gives egg a Darboux descriptive frꙮg with a falconet attachment