explain xkcd - User contributions [en]

Talk:3084: Unstoppable Force and Immovable Object

2025-05-03T19:00:47Z

172.69.194.204:

lol, i remember this explanation from a minutephysics video. however, the version of the problem i heard, which is actually paradoxical, is "what happens when an immovable object meets an '''irresistible''' force?" [[User:Not without text|Not without text]] ([[User talk:Not without text|talk]]) 00:03, 3 May 2025 (UTC)
:That was also literally my first thought. [[169]], anyone? --[[User:Coconut Galaxy|Coconut Galaxy]] ([[User talk:Coconut Galaxy|talk]]) 05:37, 3 May 2025 (UTC)
:The MinutePhysics video: [https://nebula.tv/videos/minute-physics-immovable-object-vs-unstoppable-force-which-wins/ on Nebula] or [https://youtu.be/9eKc5kgPVrA on YouTube] --[[User:NeatNit|NeatNit]] ([[User talk:NeatNit|talk]]) 09:55, 3 May 2025 (UTC)

Come on, it's just an arrow made of W- bosons, right? [[User:TheTrainsKid|TheTrainsKid]] ([[User talk:TheTrainsKid|talk]]) 03:22, 3 May 2025 (UTC)
Is there no joke here? Is it just the solution? [[User:Broseph|Broseph]] ([[User talk:Broseph|talk]]) 06:52, 3 May 2025 (UTC)

I remember an explanation by Isaac Asimov in one of his books which was like "by definition, an immovable object will not move at all under any force in the universe, and an unstoppable force will move all of the objects in this way" and then explained how the definitions conflicted each other and as such prevented both from being able to register for the hypothetical at the same time [[Special:Contributions/172.64.236.161|172.64.236.161]] 06:55, 3 May 2025 (UTC)

In the first MMO games, collision was a big problem. A player could block a doorway, and nobody else could go through. It was even worse if the player had "follower" characters or pets.
One solution was to have characters automatically "push" stationary characters out of the way, but that caused other problems. Modern MMO's such as World of Warcraft simply allow characters to pass through each other, as depicted in this xkcd comic. Our eyes fool us into "seeing" that two characters somehow slid past each other. [[Special:Contributions/172.68.228.132|172.68.228.132]] 07:29, 3 May 2025 (UTC)

When the two things pass through each other, at the instant where they both occupy exactly the same space, is there one object or two? [[Special:Contributions/162.158.216.159|162.158.216.159]] 08:02, 3 May 2025 (UTC)
:Given that force is not an object, one. Just like there was when they weren't colocated. [[Special:Contributions/172.69.43.220|172.69.43.220]] 08:29, 3 May 2025 (UTC)
::OK, but what about the 'unstoppable force carrying particles' in the title text? [[Special:Contributions/172.69.194.204|172.69.194.204]] 19:00, 3 May 2025 (UTC)

The force could simply go around the object. The object hasn't moved, and the force wasn't stopped. [[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 11:17, 3 May 2025 (UTC)

: Redirecting would imply the force could be redirected, allowing us to trap it inside a closed loop, effectively stopping it. [[Special:Contributions/172.70.57.132|172.70.57.132]] 15:38, 3 May 2025 (UTC)

This is like the Chinese saying the spear and the shield. Using this comic, I guess spear wins [[User:Aprilfoolsupdate!|Aprilfoolsupdate!]] ([[User talk:Aprilfoolsupdate!|talk]]) 14:02, 3 May 2025 (UTC)

Talk:3080: Tennis Balls

2025-04-28T08:16:03Z

172.69.194.204:

feels more like a macroscope to me [[User:GreyFox|GreyFox]] ([[User talk:GreyFox|talk]]) 23:53, 23 April 2025 (UTC)

Weirdly, Wikipedia has pages for pitching machines, bowling machines, and squash ball launchers, but doesn't appear to have one for tennis ball machines. (And no, I'm not going to create one specially for this comic.) [[Special:Contributions/172.71.241.89|172.71.241.89]] 08:42, 24 April 2025 (UTC)
:https://en.wikipedia.org/wiki/Squash_ball_machine Similar? -Anon [[Special:Contributions/172.69.208.203|172.69.208.203]] 13:31, 24 April 2025 (UTC)

:OTOH, Wikimedia has a photo and a couple of diagrams of tennis ball machines: https://commons.wikimedia.org/wiki/Category:Tennis_ball_machines and 3 photos of "Tenniskanon" https://commons.wikimedia.org/w/index.php?search=Tenniskanon&title=Special:MediaSearch&type=image . I checked and the nobody has yet created the Tenniskanon page in nl.wikipedia.org [[User:Rps|Rps]] ([[User talk:Rps|talk]]) 13:15, 24 April 2025 (UTC)

I added the comments on even smaller forms of microscopy to the article. I found these in an article I read in a friend's Nature magazine, I've almost never read Nature and this article was so interesting. There was further similar content that I wanted to add but I haven't found the article again to reference it -- there's a kind of microscopy where the energy of the probe is turned way up, so that the sample is actually immediately destroyed by the probe, but by collecting the resulting scattering it can then be reconstructed. This is relevant to the paragraph on the observer effect. There is also some kind of microscopy (pump probe?) that can collect very high-time-resolution imagery. I asked for this article at https://www.reddit.com/r/Scholar/comments/1k6vfcr/article_miao_j_computational_microscopy_with because as an ex-hobby-software-engineer I found it so interesting that simple computer algorithms could be so powerful somewhere. I think it is sad however that this comic models detached nerds harming a passerby as humor. People who are extensively exposed to a mode of research do indeed tend to apply it to other domains, because it's what they understand, but we also want them to apologize if somebody is injured :) [[Special:Contributions/162.158.154.192|162.158.154.192]] 16:00, 24 April 2025 (UTC)

With amusingly coincidental timing, I was recently made aware of a growing number of scientific papers that describe "''vegetative electron microscopes''", instead of "''scanning electron microscopes''", and I figure others here would also find it amusing: https://www.sciencealert.com/a-strange-phrase-keeps-turning-up-in-scientific-papers-but-why
The predominant theories to explain it are either that AI was trained on a pair of poorly-digitized papers from the 50s, or a translation error from Farsi, where a single dot makes the difference between "vegetative" and "scanning". Personally I find the latter explanation more likely, or perhaps a combination of the two factors.

Not sure how this concept would translate to implementing a ''vegetative tennis ball microscope''. Maybe replace the tennis balls with brussel sprouts or cabbages. [[User:PotatoGod|PotatoGod]] ([[User talk:PotatoGod|talk]]) 05:40, 28 April 2025 (UTC)

1556: The Sky

2025-04-01T22:03:24Z

172.69.194.204: /* Explanation */

{{comic
| number = 1556
| date = July 27, 2015
| title = The Sky
| image = the_sky.png
| titletext = The other half has some cool shipwrecks, rocks, and snakes, but if you move those out of the way, it also has more sky.
}}

==Explanation==
In this comic [[Cueball]] and [[Megan]] admire a majestic {{w|sky}} on a beautiful day.

This is one of the few comics where the scenery is drawn entirely in color, adding to the feeling of awe and natural wonder. The lighting on the {{w|clouds}} and the night sky in the upper corner suggest that this is either at sunset or sunrise, with the {{w|Sun}} on or around the horizon outside the left part of the image. The picture is drawn to show the ever changing beauty of the many different stages of the sky, rather than to be 100% realistic, as it would not be possible to see so many stars with the naked eye, as clearly as shown, if the Sun is still illuminating the clouds in front of them; perhaps a few of the {{w|List of brightest stars|brightest stars}}, a handful of [[3063: Planet Definitions|the planets]] and [[2809: Moon|the Moon]], though probably not all in the same convenient patch of sky at the same time. When the Sun {{w|Sunset|sets}} or {{w|Sunrise|rises}}, the light produces many different colors which can often be breathtaking to witness. The pouch shaped cloud formations are called {{w|mammatus clouds}} and are usually associated with the nearing of bad weather.

The comic, however, already starts in a small panel, with uniform sky-colored light blue background, above the large drawing described above. In this image Cueball says to Megan that he likes the sky, and Megan agrees. Megan first elaborates on her feelings in the large image, where the zoom out is so large that they have both become small and insignificant characters in the bottom left corner. They are dwarfed by the sky and cloudscape, with the ground a broad dark band beneath them.

Megan makes a statement about the sky: ''It's one of my favorite halves''. She thus indicates that she has more than one favorite half. As there are only two (non-overlapping) halves this thus implies that Megan likes both halves, i.e. she likes everything. Her statement is thus a {{w|Tautology (logic)|tautology}} because it implies that the other half is also a favorite and there are no other segments that would not be amongst her favorites. There are several xkcd comics about tautology, e.g. [[703: Honor Societies]], [[870: Advertising]] and [[1310: Goldbach Conjectures]].

In [[1368: One Of The]] ''one of'' is also used in a similar way as there is really no other that that one in that comic, whereas here there are no other that has not be included. A very similar sentence is also used in the title text of [[1524: Dimensions]] where the sentence, ''I would say time is definitely one of my top three favorite dimensions''. This also makes very little sense as there are four dimensions with time, and the other three are indistinguishable as they are just three randomly chosen but orthogonal directions in space.

Taken at face value, given that the image depicts half open sky and half clouds, the other half could be taken to mean the clouds covering half of the sky. Or it could be the sky and the dark Earth, the other half beneath their feet. That it is the latter becomes evident in the title text. But, in the title text, Megan continues her comment to state that her other favorite half has some cool objects in it, listing three types of objects:
*{{w|Shipwrecks}}
*{{w|Rocks}}
*{{w|Snakes}}
From this it becomes clear that it is not the clouds vs. the sky she's referring to but rather the sky vs. all the things in the 'other' half, on the basis of if you removed all the things in the non-sky half, including the Earth, that half would ''also'' be sky.

However, beyond the blue sky above there is just the dark {{w|night sky}} of {{w|outer space}}. If it were not for the Earth, the blue sky and its clouds would not exist, as it is formed by the air following the gravity and curvature of the Earth. So removing the entire Earth out from below you would remove the possibility of such a sky in ''any'' direction. A more selective removal ''might'' remove just enough planet to see ''some'' sky down in the lower-half, but the logistics of doing that whilst also getting a similarly unobscured view is somewhat unfathomable; even the thickness of the downwards atmosphere would make for significantly different effects, and a daylight sky above would tend to dictate that the sky directly down any hole would ultimately be a night-time sky.

This last part of the title text thus shows that Megan ''may'' be thinking rather of the night sky, and given that there are also stars visible in the top right corner, she could have assumed Cueball also referred to the sky like this rather than the majestic display of clouds and colors. Of course that would be weird, but that's where the comedy occurs because that was unexpected, and it would be typical Megan and/or [[Randall]].

If Megan is also interested in astronomy then she could also appreciate a dark and cloudless sky with stars. And by the same logic of the Earth was removed would leave only dark sky (empty space) around her on all sides, this may be considered a suitably satisfactory alternative. It is well know from xkcd that Randall really [[:Category:Astronomy|loves astronomy]] and looking at the night sky and, seen from this perspective, there would still be plenty of sky even if the Earth where removed completely. Though it would mean no clouds or atmospheric colors (or any humans or other lifeforms around to admire those astronomical objects).

==Transcript==
:[Cueball and Megan are standing looking upward with in a small frame a light blue background.]
:Cueball: I like the sky.
:Megan: Yeah.

:[Zooms out to show a blue evening sky, the sun must be setting to the left and a streak of yellow and orange clouds goes from top left to bottom right. The sky/clouds get darker further to the right and several stars are visible behind the clouds on the indigo blue sky in the top right corner. There are also some gray clouds low over the horizon. Cueball and Megan standing to the far left Below them and the sky from the horizon and down there is a thick a black slab taking up about a sixth of the frame height.]
:Megan: It's one of my favorite halves.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Animals]]

1556: The Sky

2025-04-01T22:01:57Z

172.69.194.204: /* Explanation */ Guessing that was a miskey, up a row into the numbers.

{{comic
| number = 1556
| date = July 27, 2015
| title = The Sky
| image = the_sky.png
| titletext = The other half has some cool shipwrecks, rocks, and snakes, but if you move those out of the way, it also has more sky.
}}

==Explanation==
In this comic [[Cueball]] and [[Megan]] admire a majestic {{w|sky}} on a beautiful day.

This is one of the few comics where the scenery is drawn entirely in color, adding to the feeling of awe and natural wonder. The lighting on the {{w|clouds}} and the night sky in the upper corner suggest that this is either at sunset or sunrise, with the {{w|Sun}} on or around the horizon outside the left part of the image. The picture is drawn to show the ever changing beauty of the many different stages of the sky, rather than to be 100% realistic, as it would not be possible to see so many stars with the naked eye, as clearly as shown, if the Sun is still illuminating the clouds in front of them; perhaps a few of the {{w|List of brightest stars|brightest stars}}, a handful of [[3063: Planet Definitions|the planets]] and [[2809: Moon|the Moon]], though probably not all in the same convenient patch of sky at the same time. When the Sun {{w|Sunset|sets}} or {{w|Sunrise|rises}}, the light produces many different colors which can often be breathtaking to witness. The pouch shaped cloud formations are called {{w|mammatus clouds}} and are usually associated with the nearing of bad weather.

The comic, however, already starts in a small panel, with uniform sky-colored light blue background, above the large drawing described above. In this image Cueball says to Megan that he likes the sky, and Megan agrees. Megan first elaborates on her feelings in the large image, where the zoom out is so large that they have both become small and insignificant characters in the bottom left corner. They are dwarfed by the sky and cloudscape, with the ground a broad dark band beneath them.

Megan makes a statement about the sky: ''It's one of my favorite halves''. She thus indicates that she has more than one favorite halves. As there are only two halves this thus implies that Megan likes both halves, i.e. she likes everything. Her statement is thus a {{w|Tautology (logic)|tautology}} because it implies that the other half is also a favorite and there are no other segments that would not be among her favorites. There are several xkcd comics about tautology, e.g. [[703: Honor Societies]], [[870: Advertising]] and [[1310: Goldbach Conjectures]].

In [[1368: One Of The]] ''one of'' is also used in a similar way as there is really no other that that one in that comic, whereas here there are no other that has not be included. A very similar sentence is also used in the title text of [[1524: Dimensions]] where the sentence, ''I would say time is definitely one of my top three favorite dimensions''. This also makes very little sense as there are four dimensions with time, and the other three are indistinguishable as they are just three randomly chosen but orthogonal directions in space.

Taken at face value, given that the image depicts half open sky and half clouds, the other half could be taken to mean the clouds covering half of the sky. Or it could be the sky and the dark Earth, the other half beneath their feet. That it is the latter becomes evident in the title text. But, in the title text, Megan continues her comment to state that her other favorite half has some cool objects in it, listing three types of objects:
*{{w|Shipwrecks}}
*{{w|Rocks}}
*{{w|Snakes}}
From this it becomes clear that it is not the clouds vs. the sky she's referring to but rather the sky vs. all the things in the 'other' half, on the basis of if you removed all the things in the non-sky half, including the Earth, that half would ''also'' be sky.

However, beyond the blue sky above there is just the dark {{w|night sky}} of {{w|outer space}}. If it were not for the Earth, the blue sky and its clouds would not exist, as it is formed by the air following the gravity and curvature of the Earth. So removing the entire Earth out from below you would remove the possibility of such a sky in ''any'' direction. A more selective removal ''might'' remove just enough planet to see ''some'' sky down in the lower-half, but the logistics of doing that whilst also getting a similarly unobscured view is somewhat unfathomable; even the thickness of the downwards atmosphere would make for significantly different effects, and a daylight sky above would tend to dictate that the sky directly down any hole would ultimately be a night-time sky.

This last part of the title text thus shows that Megan ''may'' be thinking rather of the night sky, and given that there are also stars visible in the top right corner, she could have assumed Cueball also referred to the sky like this rather than the majestic display of clouds and colors. Of course that would be weird, but that's where the comedy occurs because that was unexpected, and it would be typical Megan and/or [[Randall]].

If Megan is also interested in astronomy then she could also appreciate a dark and cloudless sky with stars. And by the same logic of the Earth was removed would leave only dark sky (empty space) around her on all sides, this may be considered a suitably satisfactory alternative. It is well know from xkcd that Randall really [[:Category:Astronomy|loves astronomy]] and looking at the night sky and, seen from this perspective, there would still be plenty of sky even if the Earth where removed completely. Though it would mean no clouds or atmospheric colors (or any humans or other lifeforms around to admire those astronomical objects).

==Transcript==
:[Cueball and Megan are standing looking upward with in a small frame a light blue background.]
:Cueball: I like the sky.
:Megan: Yeah.

:[Zooms out to show a blue evening sky, the sun must be setting to the left and a streak of yellow and orange clouds goes from top left to bottom right. The sky/clouds get darker further to the right and several stars are visible behind the clouds on the indigo blue sky in the top right corner. There are also some gray clouds low over the horizon. Cueball and Megan standing to the far left Below them and the sky from the horizon and down there is a thick a black slab taking up about a sixth of the frame height.]
:Megan: It's one of my favorite halves.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Animals]]

Talk:3067: SawStart

2025-03-24T12:42:57Z

172.69.194.204:

It's weird seeing a totally empty explanation, also whats the point of sawstop, don't they just use vibrating blades? [[Special:Contributions/104.23.190.110|104.23.190.110]] 12:40, 24 March 2025 (UTC)
empty explanation is freaky woah [[Special:Contributions/172.69.194.204|172.69.194.204]] 12:42, 24 March 2025 (UTC)

116: City

2025-03-01T09:38:48Z

172.69.194.204: /* Explanation */ Reauthoring redo request. Linked lexicon leaves low levels of lack! Follow feasibly favorable followups, unless unable to undertake useful uncovering of understanding.

{{comic
| number = 116
| date = June 16, 2006
| title = City
| image = city.jpg
| titletext = God, she's such a whore.
}}

==Explanation==
{{Incomplete|Some suggest the short submission can't completely convey the comic's casual comedy, or satire. Surely someone should scribe something stringently suggestive of the complete caucus of clarification, constituting corroboration of the circumstances seen in this situation.}}
The poem or description alternates between using words that start with C and words that start with S, to achieve an effect resembling {{w|alliteration}}. The gentle, romantic tone of the poem is broken by the last two words, Your Mom. This is an example of a {{w|maternal insult}} joke, and is phrased accordingly.

The title text further emphasizes this, implying that the mother in question is also promiscuous.

==Transcript==
:[A picture of various apartment buildings.]
:Shadowed city slumber silently. A second-story suite.
:Come craving courtship, selected serendipitously
:Crazed copulations, a salacious storm of continuous coitus.
:Spread, straddled, conquered.
:Countless crashed suitors strewn carelessly.
:Center, silken sheets sensuously caressing soft skin,
:Contentedly sleeps your mom.

{{comic discussion}}

[[Category:Language]]
[[Category:Your Mom]]

3047: Rotary Tool

2025-02-06T11:29:05Z

172.69.194.204: /* Explanation */

{{comic
| number = 3047
| date = February 5, 2025
| title = Rotary Tool
| image = rotary_tool_2x.png
| imagesize = 528x468px
| noexpand = true
| titletext = It was great until my thumb slipped and I accidentally launched my telescope into the air at Mach 8.
}}

==Explanation==
{{incomplete|Created by a NEWLY LAUNCHED ORBITAL TELESCOPE BOT. Do NOT delete this tag too soon.}}

It is common to find multipurpose handheld tools that can function as higher-speed drills and lower-speed screwdrivers, switching between modes with a slider. The tool in this comic appears to have extended that concept to the extreme, covering both very high-speed and very low-speed tools. Presumably the tool has a rotating part at one end that can accept multiple attachments to facilitate the different uses.

All of these speeds are sensible for the specified uses. However, engineering a single tool to perform reliably across the required range of speeds is likely to be deeply impractical. Equally, designing the base unit such that it can be usefully employed to all these purposes would be a substantial challenge. For example, a household drill needs to be both portable and reasonably bulky, whereas a record player needs good stability, and a dental drill needs to be small enough to moved flexibly and delicately. In any case, it's highly unlikely that any individual would have a need for all these uses, so the market for such a tool would be extremely limited.

The title text highlights one of the downsides of combining functions in this way — the potential for using the wrong setting for the task at hand, by carelessness or clumsiness, with detrimental effects. In this case, while attempting to use the "sidereal telescope mount" option with an actual telescope, the user accidentally changed the tool to a much higher speed setting, launching it into the air at a {{w|hypersonic speed}}. More commonly, attempting to insert a screw while on the drill setting could cause damage to the item being screwed together, the screw itself, or the screwdriver bit.

The speed of the dental drill might seem excessive, but according to [https://sableindustriesinc.com/what-is-a-high-speed-handpiece-how-it-works-speed-more/ Sable Industries], a manufacturer of high-speed dental drills, they can run "at speeds of between 300,000 and 450,000 RPM." They squirt water as they rotate to cool the bits down, so they don't overheat.

The precession setting refers to the {{w|precession of the equinoxes}}, which happens on a 26,000-year cycle that corresponds to the RPM rate shown. The average person does not need to adjust their telescope for such minor shifts, certainly not on a constant basis.{{cn}} This may be beneficial for scientists making precise measurements but they would have more powerful and dedicated tools to this end. For commercial use by the public, this would not be remotely necessary.

The speeds labeled "record player" are intended to correspond to standard rotational speeds of {{w|Phonograph record|phonograph records}}. The intended playback speed standardized at 78 rpm (not 72 rpm as depicted in the comic) in the 1920s, with a diameter of 10 inches. The speed and size, as well as the required width of the groove encoding the music, dictated a playing time of about 3 1/2 minutes per side. Beginning in the late 1940s, records designed to be played back at 33 1/3 rpm (close enough to the 33 rpm in the comic) were produced, to allow longer play times (hence the LP designation, for "long play") on similar-sized records, which standardized on a 12 inch diameter. This was commonly used to release an "album" of songs, totaling about 22 minutes per side. Concurrently, an alternate format, 7 inch diameter records designed to be played at 45 rpm, was produced, allowing about 5 minutes per side. This was often used to release "singles" (a single song on each side of the record). The 33 1/3 and 45 rpm playback speeds supplanted 78 rpm, and remain the standards today.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Multi-function rotary tool

:[A slider on the side of a tool with various settings.]
:Speed (rpm) Function
:0.000000000073: Sidereal mount precession adapter
:0.00070: Sidereal telescope mount
:[Following three are labeled "clock hands":]
:0.0014: h
:0.017: m
:1: s
:[Following three are labeled "record player":]
:33: 33
:45: 45
:72: 72
:300: Screwdriver [Current setting]
:1500: Drill
:2500: Airplane propeller
:35 000: Dremel
:60 000: Uranium enrichment centrifuge
:300 000: Dental drill

{{comic discussion}}

[[Category:Telescopes]]

3046: Stromatolites

2025-02-05T17:22:00Z

172.69.194.204: /* Explanation */

{{comic
| number = 3046
| date = February 3, 2025
| title = Stromatolites
| image = stromatolites_2x.png
| imagesize = 581x505px
| noexpand = true
| titletext = If only my ancestors had been fortunate enough to marry into the branch of the bacteria family that could photosynthesize, like all my little green cousins here.
}}

==Explanation==
{{incomplete|Created by THE MISSING LINK'S OSTRACIZED ANCESTOR - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic makes fun of claims to 'special' ancestry, such as some old royal family or similar, that may be made after doing research on a {{w|family tree}} site. These services allow the user to input the names and other information of family members and cross reference with various documents to trace lines of descent. Often, those who find a connection to a historically significant individual are quite excited about this, and may feel that it somehow makes them special. However, in reality, once you go back more than a few generations there will be many thousands of such connections, and once you get back more than a thousand years or so, anyone you could be related to will also be related to pretty much everybody else still alive in some way or other.

[[Beret Guy]] tells [[Cueball]] he has been on such a site and traced some of his family from "a few billion years back" who were related to {{w|stromatolites}}. These are layered accumulations of mineral "microbial mats" (Cueball calls them ''bacterial mats'') created by microorganisms, predominantly the oxygenic-photosynthetic {{w|Cyanobacteria|cyanobacteria}}. Some fossil stromatolites in Australia from 3.48 billion years ago contain the oldest undisputed evidence of life on Earth (though people have also claimed {{w|Earliest known life forms|other, older evidence}} for this record). Since this is some of the first life on Earth it is basically a given that all life that came after (not even just all humans) is related.

Beret Guy only claims he is related to their {{w|Alphaproteobacteria|cousins}} and that it is from their cousin bacteria that he got his {{w|mitochondria}}. His aside that he also got his cell nuclei in this way is odd, as, according to the {{w|Cell_nucleus#Evolution|leading contemporary theory}}, the ancestral archaeon ("my archaean ancestors") themselves contributed the nucleus to the original eukaryotic cell. In this model, both the archaeon and the alpha-proteobacterium were endosymbionts in a third cell, which is not consistent with Beret Guy's claim that the mitochondrion began as an archaeon's endosymbiont. Perhaps all that clicking addled even Beret Guy's brain. Anyway, he is not claiming to be a direct descendant from [the cyanobacterial component of] stromatolites, which makes sense since they can photosynthesize, and as he mentions in the title text, he cannot!

Ancestry services typically do not allow the user to track their familial history prior to written records{{citation needed}}, but with his [[:Category:Strange powers of Beret Guy|strange powers]] it is no wonder that Beret Guy could make this work! (Some do provide genetic sequencing, which allows for more information to be acquired, but this isn't accurate enough to track individual people who lived before such technology existed on a wide scale.) He may also have needed to rely on these powers to do all the clicks needed to go back that far in the past. Even at a rate of 10 to 15 clicks per second it would still take thousands of years — maybe even more due to how fast cells can reproduce — to do enough clicks to work back this far from scratch. However, it may be that a large part of the tree had already been constructed by previous users, and all he had to do was find a relation already attached to this tree. This would further underline how un-special his newly discovered relationship is.

Cueball asks if he would like to contact his distant relatives, since there are still living stromatolites today (or at least something very similar to those from billions of years ago). But Beret Guy imagines they are busy so he will not bother them. When asked by Cueball what he would use his newfound knowledge for, he lies down on the hill they have climbed to bask in the sun. Because as he says, "Lying on a hill in the warm sun is an old family tradition." This is basically the only thing stromatolites can do, but they are doing it all the time and could thus be said to be busy with this. It seems, however, like Beret Guy is going to enjoy this tradition.

In the title text Beret Guy muses about how great it would have been if his distant relatives had married into the branch of the bacteria family that could photosynthesize... and then refers to the grass he is now lying on as "my little green cousins here". If this had happened he would either have been able to lie on the hill without eating since [https://www.gocomics.com/doonesbury/2014/10/28 he would be able to photosynthesize] getting energy directly from the sun (instead of eating some of his small green cousins' closer relatives) - although that might not be enough to sustain him, as per ''[[what if? (blog)|what if?]]'' article ''{{what if|17|Green cow}}''. Or else he would actually have been a plant instead.

==Transcript==
:[Cueball and Beret Guy, seen from afar in silhouette, are walking up a grassy hill.]

:[They continue walking up the hill, reaching its grassy summit. Now with normal lighting. Beret Guy is a bit ahead of Cueball.]
:Beret Guy: I learned something today.
:Beret Guy: I went on one of those family tree sites and kept clicking back, and it turns out I'm related to stromatolites!

:[Closeup on Cueball. Beret Guy's reply comes off-panel from a starburst on the right edge of the panel.]
:Cueball: The bacterial mats?
:Beret Guy [off-panel]: Yeah! A few billion years back, on my mitochondria's side.

:[Cueball and Beret Guy standing on the top of the grassy hill facing each other. Beret Guy holding a hand out towards Cueball.]
:Beret Guy: My Archaean ancestors absorbed some bacteria that were cousins of stromatolites. That's how I got mitochondria.
:Beret Guy: Cell nuclei, too.

:[Cueball is standing behind Beret Guy who is now sitting down in the grass leaning back on one arm with the other arm resting on his bent knee.]
:Cueball: I think there are still living stromatolites. You could get in touch.
:Beret Guy: Nah, they're probably busy. I don't want to bother them.

:[Cueball is sitting behind Beret Guy who is now lying down, both again shown in silhouette from a far, revealing they are on the top of the grassy hill.]
:Cueball: So what ''are'' you going to do with this knowledge? Nothing?
:Beret Guy: Lying on a hill in the warm sun is an old family tradition.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Beret Guy]]
[[Category:Biology]]

3032: Skew-T Log-P

2025-01-03T15:09:25Z

172.69.194.204: /* Table with terms */

{{comic
| number = 3032
| date = January 1, 2025
| title = Skew-T Log-P
| image = skew_t_log_p_2x.png
| imagesize = 569x626px
| noexpand = true
| titletext = The most important quantity for meteorologists is of course the product of latent pressure and temperostrophic enthalpy, though 'how nice the weather is' is a close second.
}}

==Explanation==
{{incomplete|Created by a BOT CLEANING UP AFTER DAVE - This needs an explanation. Table not filled out. Also the title text was not mentioned at all. I added a very simple start to this, but nothing about what the product actually means, please expand... Do NOT delete this tag too soon.}}

{{w|Skew-T log-P diagram}}s are commonly used to plot {{w|atmospheric sounding|atmospheric soundings}} collected by {{w|weather balloon|weather balloons}} or {{w|Constant altitude plan position indicator|other}} [https://rmets.onlinelibrary.wiley.com/doi/abs/10.1002/wea.658 methods]. The name comes from the temperature (T) lines being skewed at a 45-degree angle and the pressure (P) lines being logarithmic in scale. Although it ''looks'' very much like a cross-sectional diagram, it shows non-positional information derived from passing (generally) vertically up through the atmosphere from the initial reference location.

Because the diagrams have a lot of lines on them (isobars, isotherms, adiabats, and mixing ratios, and that's before plotting the actual measurements of temperature and dew point temperature), they can be hard to comprehend. The comic pretends to offer an explanation of one such diagram, but most of the explanations are blatantly incorrect or humorous in nature. The diagram appears to have either measurements from two separate weather measurements or the measured temperature and dewpoint from a single balloon, with solid lines for the primary balloon's two streams of data (often disambiguated by the chosen hue of the line) and dashed ones for the secondary set of data (popped balloon(s) falling back down, a separate second survey balloon rising or estimates derived from weather-radar data). See details in the [[#Table with terms|table]] below. Many weather balloons are designed to rupture after reaching a certain height high in the atmosphere.

[[File:Annotated_Skew_T_diagram.png|thumb|An actual Skew-T Log-P diagram, with several real annotations. The X-axis has temperature (blue diagonal lines in diagram) and the Y-axis has pressure in millibars.]]The true design of a Skew-T Log-P diagram is intended to best represent the nature of the weather in any given column of atmosphere. The pressure (vertical axis, with pressure being inversely related to altitude, more or less) is shown as a logarithmic scale (i.e., Log-P) because it makes altitudes nearly evenly spaced. Plotting pressure proportionately (which must also be from top to bottom, to match its general relationship with altitude) would space features out in ways that would be hard to use and interpret, whereas the logarithmic scale is far more pragmatic. The temperature scale is deliberately tilted, rather than orthogonal, which (together with the logarithmic nature of the inverted pressure scale) allows the typical way that temperatures fall with altitude(≈as pressure falls) to trend roughly vertically, give or take the notable changes that are key to understanding the forecast. Other measurement lines, differently skewed and often also curving across the temperature/pressure skewed-log 'grid', represent various other idealistic relationships (where both T and P vary, keeping another measure constant) that are useful references to meteorologists.

Upon this style of graph are plotted the ''actual'' measurements obtained by releasing a weather balloon or through some other sensor. As well as the variation of actual temperatures and pressures, other retrieved and calculated data is plotted, such as the {{w|dew point}}. The dew point, a function of the air's {{w|absolute humidity|water content}}, temperature, and pressure, is where condensation begins. By observing how the actual measurements and dew point line converge and cross, the development and nature of clouds can be tracked and pinned to specific cloud layers. Further details may also be included, such as wind-direction and wind-speed indications (often to the side of the plot) to give a visual cue about possible {{w|wind shear}} and/or to suggest which direction of adjacent weather-station readings may hold clues as to what changes may later blow in above the current site.

In the title text it is stated that "The most important quantity for meteorologists is of course the product of latent pressure and temperostrophic enthalpy, though 'how nice the weather is' is a close second". So it jokes by comparing a non-existent, complicated-sounding product (temperostrophic enthalpy is not actually a thing) with a simple sentence about how nice the weather is.

==Table with terms==
{| class="wikitable"
!Item in comic
!Correct?
!Explanation
|-
| Pressure latitude || No || {{w|Pressure altitude|Pressure ''altitude''}} is the height above a standard datum plane, a theoretical level where the pressure of the atmosphere is 1013.24 millibars (29.921 inHg). It's essentially an estimate of altitude calculated from atmospheric pressure.
|-
| Enthalpic pressure || No || {{w|Enthalpy}} is the total internal energy of a thermodynamic system plus the product of the system's pressure and volume. Essentially, it represents the energy contained in a system, and is independent of the means or sequence of operations that the system went through to achieve its current state.
|-
| Entropic density || No || {{w|Entropy}} is a quantity that shows many physical processes can only go in one chronological direction. An egg can easily be scrambled (increasing its entropy), but it is very difficult to "un-scramble" an egg[[[285: Wikipedian Protester|''citation needed'']]][[Category:Pages using the "citation needed" template]] (which would decrease its entropy). Ordered systems have low entropy, with differences in temperature, pressure, potential energy, or the like. Disordered systems have high entropy, without temperature, pressure, electrical, or other differentials.
|-
| Latent heat of cooling || No || {{w|Latent heat}} is the energy absorbed or released by a system during a '''constant-temperature''' process, like melting, freezing, boiling, or condensing. Cooling is a process of lowering a temperature, and therefore not a constant-temperature process. The humor comes considering the "heat of cooling."
|-
| Isobars || Yes || Lines denoting equal ("{{wiktionary|iso-}}") air pressure ("{{wiktionary|bar-|-bar}}"), probably most often recognized as the indicators of how ground-level pressures change (or not) across the horizontal area depicted on a weather ''map''. In this type of chart, which depicts data obtained from above a single point, it has the same meaning but is instead a pre-existing reference line across which the actual data is plotted, and does not itself indicate the nature of any wind.
|-
| Omnitrophic wind || No || Something "omnitrophic" would apparently be "all-eating", in some scientific sense. An omnitrophic wind would probably be a concerning phenomenon.
Probably a play on something like {{w|geostrophic wind}} ("geo"+"strophic" being from "Earth curving"), a theoretical state of wind that results from an exact balance between the {{w|Coriolis force}} and the {{w|pressure gradient}} force.
|-
| Isomers || No || Different forms of molecules with the same formula, with the atoms or functional groups arranged differently. An example would be propanol, which has three isomers. One of the most common isomers of propanol has its OH functional group in the middle, so is called isopropyl alcohol or isopropanol.
However, these are actually iso'''therm''' lines, representing equal temperature.
|-
| These lines are slightly different because Dave messed them up || No || Indicating isotherms (or, according to the comic, "isomers"), the suggestion is that slightly wrong lines were drawn by Dave and had to be corrected.
The real reason for the not quite identical lines is that the measured temperature at a given pressure can be converted to or from the ''potential'' temperature that the same air would have if at a standard pressure (holding the same amount of heat energy). For practical reasons, both for composing and interpreting the eventual plot, each of the slightly differently skewed isotherms are given, usually in clearly differentiable styles of line.

The "Dave" of the description may be David Bolton, whose 1980 paper introduced a means of calculating the atmosphere's potential temperature<ref>https://journals.ametsoc.org/view/journals/mwre/108/7/1520-0493_1980_108_1046_tcoept_2_0_co_2.xml</ref>.
|-
| Line of constant thermodynamics || No || {{w|Thermodynamics}} is a branch of physics concerned with work, temperature, heat, the way they relate to entropy, energy, enthalpy, and the physical properties of radiation and matter. As a field of study, Thermodynamics does not have '''constant lines,''' except perhaps as a means of describing a consistent avenue of research.
|-
| Uncomfortably moist adiabat || Wrongly placed, unusually qualified|| This labels a segment of isotherm, which is the exact 'opposite' of an adiabat.
An adiabat is a line along which temperature can change for a given mass, without changing the amount of energy. This is primarily made possible by changing the density (by a change in pressure) of the gas. There are typically two types of adiabat, marked for reference on the plot, "dry adiabat" (curves across the isotherms perpendicularly, to create a largely square but slightly curved grid with them), and "moist/saturated adiabat" (the latter's heat-maintaining profile is influenced greatly by the humidity content, and produces graphing lines vastly different from the equivalent "dry" versions). Randall has declared this (erroneous) type of adiabat to be "uncomfortably" moist, so presumably not totally saturated but also not subjectively 'pleasant'.
|-
| Oops, the balloon flew through a ghost || No || Ghosts do not exist.{{cn}} However, one of the purported effects of ghosts (such as in the film *The Sixth Sense*) is a transient/local lowering of temperature around and/or inside them. The line is interpreted as showing a local low temperature encountered at this pressure(/altitude).
This line, however, is probably the dew point line, indicating that in passing through this layer of the atmosphere, a drier band of air was encountered which would theoretically be cooled a lot more before the water-vapor oversaturates it and liquid water droplets form.
|-
| No birds up here :( || Yes* || This point is near the top of the diagram, with an air pressure of about 110 millibar - about 15 kilometers (50,000 feet) above sea level. This is well above the highest [https://peregrinefund.org/explore-raptors-species/vultures/ruppells-vulture flight height of any known bird species]. However, this information is irrelevant to the purpose of a skew-T log-P diagram.
|-
| Track of rising weather balloon || Yes, partially || Although there are other ways of recording these details, this is typically the record of a rising balloon.
However, it would be a track of the balloon through the varying pressures and temperatures that it records (as the second line of this type records the measurements of dew point at each pressure value). Moreover, circumstances that would make the recorded data plot out a neat {{w|figure-eight knot}} (see "Seems bad", below) are very unlikely.
|-
| Track of popped balloon falling back down || Possible, partially || A standard plot track will include two strong lines, as this has, representing not ''two'' balloons but the recorded temperature track ''and'' the dew point track, both against the (altitude surrogate) progressive pressure changes at each pressure-point.
A further pair of tracks as dotted lines could possibly be from a different launch (earlier, later or simultaneous from an adjacent location) as an analytical reference, but ''may'' indeed be the additional results obtained as the scientific package rapidly descends once the balloon pops.
|-
| Meteogenesis || No || The chart purports to show the path of two weather balloons crossing and labels the space between them with a new word. The root "meteo" means something high up (in this case, balloons) and "genesis" means creation. The implication is that a new balloon was created, though no third flight path is shown so it presumably did not fly separately or was not tracked.
In reality, one of the tracks (almost certainly the left one) is the track of the measured dew point. Where the line of the existing conditions cross this line is where the moisture will precipitate out and form clouds, a process that might well be called "{{wiktionary|meteor#English|meteo}}+{{wiktionary|genesis#English|genesis}}", but {{w|Cloud physics|isn't}}.
|-
| Seems bad || Not a common feature || The path of the balloon loops around in the shape of a {{w|figure-eight knot}}, which would indicate very chaotic conditions at that point, if taken as positional informtion
As the actual Skew-T Log-P graph does not record positional information, this is best interpreted as having encountered a fluctuating temperature as the pressure decreases, continuing as something (possibly {{w|Wind shear#Vertical component|vertical wind shear}}, or some form of compression waves, encounter the instruments) creates a temporary increased in external pressure and then circumstances return it to its more typical altitude-induced pressure-drop. Though this is not ''impossible'' to naturally happen, it might even be best interpreted as the instruments being deliberately 'buzzed' by a passing aircraft or rocket, including some intermittent form of thermal backwash as the interfering craft criss-crosses the balloon's physical track in a briefly complex encounter.
 Whatever happened to the temperature/pressure track, it apparently did not significantly change the associated dew-point/pressure track (if the pressure did indeed temporarily rise, the related dew points repeated themselves each time the pressure values were re-encountered).
|-
| Dew point || Wrongly represented || The temperature at which water condenses out of the air, and therefore dew starts to form, given the amount of water vapor in the air. It is shown here as an ''actual'' single point, when it should be a line (typically the leftmost solid plotted line) representing the temperature at which dew should form at any given pressure.
|-
| Humidor || No || In reality, is a {{w|Humidor|container}} that is used maintain a more controllable humidity within which to store smoking products. In the graph, points at the line that is probably representing the dew point, which is represents the ''actual'' humidity encountered.
|-
| Heavyside layer || No || In the metaphysical cosmology of the musical ''Cats'', the Heavyside Layer is a blissful afterlife which all the cats in the musical long for. It is likely included here as a comical misspelling of the {{w|Kennelly-Heaviside layer|(Kennelly-)Heaviside layer}}, also called the E region of the {{w|ionosphere}} that was co-discovered by {{w|Arthur E. Kennelly}} and {{w|Oliver Heaviside}}. In this diagram it is apparently labeling a heavily marked isotherm, or line of constant temperature - most likely the 0°C line, the freezing point of water that is of great importance to meteorologists, pilots, etc.
|-
| These lines are tilted because the wind is blowing them || No || The wind is not actually a derivable featured of this diagram, which does not have data of either direction or strength of air movement.
These lines are actually dry adiabats (see above), possibly two sets due to a similar renormalized interpretation, as with the isotherms, at a given reference pressure.
|-
| Don't stand here or you might get hit by a balloon || No || On the misguided basis that this is a cross-sectional diagram, this would be the imagined release-point for the balloon(s) involved. And, if you're particularly (un)lucky with the winds, where they eventually fall straight back down to once the balloon has popped.
However, this is a diagram of some measurements ''for'' a location, not directly indicating a range of places you could choose to stand, and the bottom of the lines indicate the conditions ''at'' the release point (and possibly then the point of landing), regardless of where those lines appear to be rooted. To be accurate, the whole width of the the table (and at a 'height' that represents the actual recorded ground-level pressure for that location and time) is where any 'danger' may be, but the person initially releasing the balloon would not normally be too fazed by being struck by a wind-buffetted balloon (if anything, they'd be more concerned at damaging it prior to release). The attached remains of popped balloon that is no longer buoyant wil generally also act as a form of parachute (together with any actual drogue chute) to make any the light (and often well padded) payload descend slowly enough to not be a falling danger.
 Having traveled tens of kilometres up, before gently coming down, the chances of any given balloon landing in any given awkward spot (let alone the point of release) are low. Where possible, the sensor package and the remains of the balloon may be recovered, but the largest danger may instead be the environmental effects of the fragments of burst balloon, scattered to the very winds they were originally measuring.
|-
| Temperostrophic enthalpy (''Title text'') || No || The largely nonsensical first word perhaps could be interpreted as "time-warping", and allude to the varying passage of time experienced by those who do or do not understand these charts, on having to examine them.
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:How to interpret a skew-T log-P diagram
:[The comic shows a skew-T log-P diagram. On it are various labels, including isobars, comments, and other interpretations of the diagram.]
:[Left to the diagram is an upwards-pointing arrow with the label "Pressure Latitude". Right to the diagram is a downwards-pointing arrow with the label "Entropic Density". Below the diagram is a right-pointing arrow with the label "Enthalpic Pressure".]
:[Two solid and dashed lines extend from the top line to the bottom line of the diagram.]
:[The remaining various labels are inside the diagram.]

:[Labels on the left:]
:[An arrow pointing to a densive dashed segment attaching to one solid line:] Latent heat of cooling
:[A label lying on one horizontal guide:] — Isobars —
:[An arrow pointing to the intersection of one solid and dashed line:] Omnitrophic wind
:[A label lying on one left-downward guide:] Isomers
:[A label lying on one right-downward guide:] Line of constant thermodynamics
:[An arrow pointing to a solid dashed segment on one left-downward guide:] Uncomfortably moist adiabat
:[An arrow pointing to the same solid line as ‘latent heat of cooling’:] Humidor
:[An arrow pointing to a steep peak on the same solid line:] Oops, the balloon flew through a ghost
:[To adjacent arrows pointing to two left-downward guide not perfectly coinciding to each other:] These lines are slightly different because Dave messed them up
:[An arrow pointing to the end of solid and dashed lines on the bottom line:] Don’t stand here or you might get hit by a balloon

:[Labels on the right:]
:[An arrow pointing to the top line:] No birds up here :(
:[An arrow pointing to one solid line generally:] Track of rising weather balloon
:[An arrow pointing to one dashed line generally:] Track of popped balloon falling back down
:[An arrow pointing to crossing of two solid lines, The area enclosed by which is painted black] Meteogenesis
:[An arrow pointing to a knot on one solid line:] Seems bad
:[An arrow pointing to a dot] Dew point
:[An arrow pointing to a highlighted left-downward guide:] Heavyside layer
:[Text written sideways below the line:] These lines are tilted because the wind is blowing them

==Trivia==
*Even though this comic was released on New Year's Day 2025, it was not a [[:Category:New Year|New Year comic]].
**Only second time this has happened since New Year comics became a regular thing from 2011.

{{comic discussion}}

[[Category:Charts]]
[[Category:Weather]]

3031: Time Capsule Instructions

2024-12-31T11:14:02Z

172.69.194.204: /* Explanation */

{{comic
| number = 3031
| date = December 30, 2024
| title = Time Capsule Instructions
| image = time_capsule_instructions_2x.png
| imagesize = 692x235px
| noexpand = true
| titletext = Inside is a third box, labeled DO NOT OPEN UNLESS YOU ARE IN THE TIME ZONE WHERE YOU OPENED BOTH PREVIOUS BOXES.
}}

==Explanation==
{{incomplete|Created by an ANNUAL TIME CAPSULE SUBSCRIPTION - Please change this comment when editing this page. Do NOT delete this tag too soon. Do NOT delete this tag too late either.}}
The instructions for opening the first box preclude opening the second... at least without inventing a time machine / changing calendars.

The title text addressed the only way one can open the first two boxes without ignoring the instructions: by crossing time zones. When more easterly-referenced locations have become the 1st of January 2025, it will (for a short while) still be the 31st of December 2024 in more westerly ones (the boundaries themselves might be any orientation, not just north-south; the whole concept inverts across the International Date Line, before even considering hour-shift differences), meaning that theoretically someone could open the first box in a time zone where it is 2025 and then travel to one in which it is still 2024 to open the second box. However, the title text implies that if you take advantage of this loophole, you will not be allowed to open the third box as it requires that you have not made any such move.

Depending on interpretation, you could defeat the third box by placing it inside two time zones at once before opening it, as there is no time limit on the third box. This works if the instruction on the box is read as "unless you are in the time zone where you opened the first box, and you are in the time zone where you opened the second box". However, this new loophole could be patched by interpreting the third box as "unless you are in the ''one'' time zone where...". Another possible solution would be for both the box and the person opening it to be on the boundary between two time zones, half in each. Yet another possible solution would be to change the calendar used as point of reference: {{w|Calendar_era|many calendars}} use a lower year than the Gregorian calendar.

Depending on how one interprets the nature of Daylight Saving Time, there may be another solution. In Australia, {{w|Northern Territory}} and {{w|South Australia}} are in the same time zone (by the most common interpretation of the word) and border each other, but only the latter uses Daylight Saving Time; similarly, {{w|Queensland}} does not use Daylight Saving Time but is in the same time zone (by the most common interpretation of the word) as multiple Australian territories that do use Daylight Saving Time, including {{w|New South Wales}}, with which Queensland shares a border. This suggests the idea of opening the first box in South Australia or New South Wales then taking it north of the (horizontal) DST boundary without crossing any (vertical) time zone boundaries; one will then have up to an hour to open the second box and then as long as one wants to open the third box. However, Randall [[:Category:Daylight saving time|has historically expressed opposition to Daylight Saving Time]], so he might not count the first opening as occurring in 2025 if that year has already started only by virtue of Daylight Saving Time. Of course, one could just disregard the words on the boxes (or at least Randall's interpretation of them); there is probably not some kind of [[242: The Difference|magical enforcement mechanism]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[A frame with a Time Capsule sign. Cueball and Megan are clinking wine glasses. Ponytail is digging with a shovel.]
:Off-panel sound: ''Happy New Year!''

:[A frame showing a worn-out box labeled "DO NOT OPEN UNTIL 2025"]

:[A frame where Ponytail opens the box while Cueball and Megan watch.]
:Click

:[The box is revealed to contain a second box labeled "DO NOT OPEN AFTER 2024"]

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Ponytail]]
[[Category:New Year]]
[[Category:Time]]

3026: Linear Sort

2024-12-19T13:33:29Z

172.69.194.204: /* Explanation */

{{comic
| number = 3026
| date = December 18, 2024
| title = Linear Sort
| image = linear_sort_2x.png
| imagesize = 385x181px
| noexpand = true
| titletext = The best case is O(n), and the worst case is that someone checks why.
}}

==Explanation==
{{incomplete|Created in Θ(N) TIME by an iterative Insertion Sorter working on a multidimensional array - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
A common task in programming is to sort a list, a list being a collection of related elements of data that are stored in a linear fashion. There are dozens of algorithms that have been created for this through the years, from simple to complex, and each has its own merits with regards to how easy it is to understand / implement, how much space it uses, and how efficiently it operates on the data.

In computer science, the runtime of an algorithm can be described using {{w|Big O Notation}}, which categories the asymptotic, usually average, runtime (''O'') of a function of the number of elements (''n'') operated on (''f(n)'') as it grows larger and larger towards infinity; this creates the form O(''f''(''n'')) as the final description. Being asymptotic means that Big O Notation only considers parts of the function that scale with time and disregards fixed changes such as multipliers and additions to the scaling time ( 'lesser' scalings are also generally discarded). O(2''n'') is essentially O(''n''), while O(2''n'' + ''n''2) has 2''n'' practically eclipse the significance of the ''n''2 in the long term. In practice, an O(''n'') algorithm takes a constant additional amount of time per element operated on, O(log ''n'') suffers less relative increase as the input complexity does, while O(''n''{{w|Factorial|!}}) generates vastly more! This does not make claims about how much time a single base unit of complexity takes to complete, or that from lesser overheads, as that relies upon specific hardware and software benchmarks, but gives the trend in a way that is usually directly comparable between any number of alternate methods implementable in exactly the same situation for an arbitrary usage case. A simple example would be examining pictures in sequence: if it takes one second to look at a picture, it would take ten seconds to look at ten pictures; if it took three seconds to look at a picture, it would take thirty seconds to look at ten pictures — both are described as O(''n'').

Generally, programmers seek to minimize the Big O Notation of their algorithms because it means they take less time. It can be proven that all general-purpose sorting methods have an average-case lower bound of {{w|Big O notation#Big Omega notation|Ω}}(''n'' log ''n'') for all possible input orders; since this is larger than ''n'' on its own, it means that algorithms will always begin to take longer per element as the number of elements increases. This still depends upon the algarithm and the data, as something like an {{w|Insertion sort}} can work in O(''n'') time if given a list already in the correct order, or O(''n''2) if it needs to be reversed.

Here are some examples of common runtimes expressed in Big O notation, from smallest to largest:
<ul><li>O(1) - Constant time, which means the execution time is independent of the size of the data</li>
<li>O(''n'') - Linear time, which means the execution time grows in direct proportion to the size of the data</li>
<li>O(''n'' log(''n'')) - The execution time grows proportionally to ''n'' * the {{w|logarithm}} of ''n'', with the added ''log(n)'' creating an increasingly larger multiplier on the runtime</li>
<li>O(''n''2) - Quadratic time, meaning the execution time grows proportionally to the ''square'' of the size of the data.</li></ul>

The code in the comic describes a 'linear' sort that first sorts the list using {{w|merge sort}}, which is known to take time O(''n'' log(''n'')), and then `sleep()`s (pauses with no activity) for a complementary amount of time by subtracting the time taken for the sort from the number of elements multiplied by 1 million (1e6) seconds. This way, the total time always scales proportionately with the number of elements. This effectively converts the algorithm, through brute force, to fit the definition of linear time: it takes one million seconds — which is more than 11 days — per element, rather than a non-linear progression as the number of elements increases. Although this algorithm ''does'' run in O(''n''), it does not reflect that it is made to be significantly slower than the nominally 'worse' O(''n'' log(''n'')) performance that the embedded sort takes by itself.

It should be noted that for sufficiently large lists, the merge sort will take longer than the million seconds per element, which results in a negative value being passed to the sleep() function. This might halt the program with a runtime error, produce {{w|Integer overflow#Definition variations and ambiguity|unpredictably extra-long}} additional waits or skip any additional wait; all of these still leaving the issue of already having exceeded O(''n''). However, this issue will only arise for impossibly huge lists: if, for instance, a merge sort took ''n log(n)'' microseconds to complete (which would be considered slow, by today's typical processing times), then the comic's 'linear' sort target would be reached sooner only for lists longer than 21,000,000,000,000 ≈ 10300,000,000,000 elements — a number far larger than the number of atoms in the universe. The practical impossibility of this outcome might be why such a ridiculously high number of seconds was chosen.

The title text refers to the {{w|Best, worst and average case|best and worst case}} of a sort, which are additional measures of its runtime to describe the shortest and longest potential times. A more optimal sort may decide how much of a list needs to be passed over again after its first pass of shuffling elements around; scanning a pre-sorted list (and deducing that it has no more checking to do) could mean that no more effort is needed, resulting in a best case of O(''n''). Depending upon the algorithm, presenting a list that is in an ordering that happens to challenge it the most (such as exactly reversed) may mean even an 'average O(''n'' log ''n'')' process would have to exceed this, resulting in a worst-case number of operations that may be O(''n2''). It can be very useful to know that a given sorting method ''may'' take the average order of time, but have the possibility of a much shorter ''or'' longer runtime... especially when the method is expected to be [[1185: Ineffective Sorts|far, far worse than others]], where only particular and more idealistic input lets it approach the more satisfyingly fast average/best responses.

By forcing all practical searches to take O(''n'') time, regardless of how otherwise identical data is presorted, the best case (and worst case, for that matter) will also be O(''n''). The last part of the text then plays on another meaning of best case and worst case, as best- and {{w|worst-case scenario}}s for a situation, by saying that the worst outcome for the code's author is when someone decides to investigate the code (perhaps owing to its absurd runtime, or else just justifiably skeptical of the declared optimality), whereupon that investigator will discover the deception and ruin the author's reputation.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[The panel shows five lines of code:]
:function LinearSort(list):
::StartTime=Time()
::MergeSort(list)
::Sleep(1e6*length(list)-(Time()-StartTime))
::return

:[Caption below the panel:]
:How to sort a list in linear time

{{comic discussion}}

[[Category:Programming]]

User talk:CalibansCreations

2024-12-11T17:21:32Z

172.69.194.204: /* "{{diff|359134|On the off-chance...}}" */ *cough*

Please chat with me below.
----

== 1946?? Yes, at one point. ==

The change made [https://en.wikipedia.org/w/index.php?title=Car_wash&diff=prev&oldid=1212096331&diffonly=1 here] marks the point where the valid header/anchor of "1946" was removed. These things happen, especially cross-wiki. Just so you know (I was intruigued myself, so did a couple of minutes digging). Nice catch, though! [[Special:Contributions/172.70.85.139|172.70.85.139]] 10:46, 10 October 2024 (UTC)
:oh, my first talk page message, thx. [[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 11:44, 10 October 2024 (UTC)

==Politics intrudes==
randall still supports zionist harris... :'( [[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 07:49, 17 October 2024 (UTC)
: Do you really think Trump would be better? [[Special:Contributions/172.68.205.135|172.68.205.135]] 09:18, 17 October 2024 (UTC)
::i mean, both of them suck tbh [[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 09:35, 17 October 2024 (UTC)
:::so whats your alternative suggestion? Voting/Endorsing for a third party and then get trump into office? Great strategy --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 10:46, 17 October 2024 (UTC)
::::that ain't how it works. if we all vote for the third party, the third party will win. simple as that. [[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 11:30, 17 October 2024 (UTC)
:::::''Which'' third-party? Vermine Supreme? [[Special:Contributions/172.70.90.206|172.70.90.206]] 12:04, 17 October 2024 (UTC)
:::::Who exactly is "we all"?
:::::Nobody outside of your little internet bubble is voting third-party, because doing so without mass coordination is just throwing your vote away (meanwhile MAGA are all fully coordinated in voting for Trump).
:::::The risk of a Trump second term is bad enough even with everyone who is anti-Trump voting for Harris, and you think the average person over the age of 20 is going to risk that even further by voting for a third party?[[Special:Contributions/172.69.195.106|172.69.195.106]] 12:25, 17 October 2024 (UTC)
: I think you err if you think that "supports Israel against attackers" totally equates to "supports Israel's uncompromising attacks on others". And "Zionist" is such a loaded term, with {{w|Zionist antisemitism|various complications}}, with Kamala being no more this than is her primary opponent.
: Being consistently critical of one candidate by using a single word (e.g.. "fascist", for the other one) does not bode well for your appreciation of the many subtleties that make up anyone other than a cartoon hero/villain. Not that even the reality of the State Of Israel is simple (there are plenty of its citizen residents who decry their government's actions since/before last October, are they ''anti-''Zionist?), and even that is just a single relatively small mess in the much bigger mess that is the wider morass of foreign (and domestic) policy. By picking just one dogwhistle term (arguably in a very incorrect context) isn't helping whatever argument you're trying to make. All I get from this conversation is that you hate every candidate with any chance of winning (and most of those without, based upon their stated positions), without knowing what you are for. Employment? Social safety-nets? Smaller goverment? ''Better'' (define 'better'!) government? Who would you prefer to 'deal with' the issue of Ukraine, Taiwan, North Korea or countless other worldside issues out there?
: You also elsewhere announced yourself as a Brit (as am I), so you don't have a vote and precious little actual influence. Even if you or I had any useful analysis to say about this issue, it seems that most people are already polarised in opinion and you or I (or, indeed, Randall) can do little but be performative about our current views. It is unlikely we could swing even one notable vote, although we might just push some of the partially polarised fully over (whichever way) into their pre-chosen preferences, excited or annoyed by such a single-issue outburst that they find themself vehemently agreeing or disagreeing with. (As a Brit, I'm frankly embarrassed by those who put up "this house is supporting the LibDem/Labour/Tory/SNP/whoever candidate" signs in their windows. I'd put up OMRLP ones, maybe, but I've never been able to vote that way, anyway, so can certainly say that I've actually never voted for them. Even if they sometimes seem the better choice.)
: Furthermore, it has absolutely nothing to do with this comic (US geography, yes, US politics, no). I would heavily advise you to take this whole section out and place it all somewhere else. Perhaps your User Talk: area, so that you can wear your heartfelt antizionist (and perhaps no more) opinions on your sleeve without distracting from more relevent discussion, such as "Why is Idaho unlabeled" or "Why does everyone mississremember Mississippi's postostostal code?" [[Special:Contributions/172.70.90.206|172.70.90.206]] 12:04, 17 October 2024 (UTC) Postscript: *I* have moved this. <-that IP
:Quick question, CalibansCreations. Are you the same IP troll who said that Randall supports Zionism? [[User:42.book.addict|42.book.addict]] ([[User talk:42.book.addict|talk]]) 15:16, 17 October 2024 (UTC)
::yes, I only wanted an account so I could change the skin of this website when viewing it [[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 15:39, 17 October 2024 (UTC)

== Name ==

Hey CalibansCreations, thanks for reverting my talk page. My name’s Victoria, as shown on the edit leaderboard. The “Charlie Spring” name was just a pseudonym back then. :) [[User:42.book.addict|42.book.addict]] ([[User talk:42.book.addict|talk]]) 15:15, 22 October 2024 (UTC)
:Oh, pleasure to meet you Victoria! You can just call me Caliban or Cal. (That's my own pseudonym.) [[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 19:27, 22 October 2024 (UTC)

==Barnstar==
{| style="border: 1px solid {{{border|gray}}}; background-color: {{{color|#fdffe7}}};"
|rowspan="2" style="vertical-align:middle;" | {{{{{|safesubst:}}}#ifeq:{{{2}}}|alt|[[File:Barnstar of Reversion Hires.png|100px]]|[[File:Barnstar_of_Reversion2.png|100px]]}}
|rowspan="2" |
|style="font-size: x-large; padding: 0; vertical-align: middle; height: 1.1em;" | '''The Anti-Vandalism Barnstar'''
|-
|style="vertical-align: middle; border-top: 1px solid gray;" | <div style="font-family: Cormorant Garamond"> For your help in reverting vandalism on my talk page, [[User:CalibansCreations|'''Caliban''']], I hereby award thee a Barnstar. Feel free to display it on your user page. [[User:42.book.addict|42.book.addict]] ([[User talk:42.book.addict|talk]]) 21:13, 24 October 2024 (UTC) 
</noinclude>
:oh wow tysm --[[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 07:42, 25 October 2024 (UTC)
|}

== Full template name ==

I wouldn't normally change existing {{template|cn}}s to {{template|Citation needed}}s. However, it makes even less sense to replace the latter with the former, them being the same at the front end (the smaller being a redirect to the larger, so making a ''little'' bit of extra work for the server) but being less obvious/noticable for what it is in the source edit.

Even with editing to shuffle it vs. wrongly-arranged punctuation, it's surely simpler to delete the punctuation from (say) <tag><comma> and replacing it to create <comma><tag> than deleting the tag and re-adding the short (but still longer than punctuation) form of the tag. I mean, it's entirely up to you, but I'd keep it just as readable. [[Special:Contributions/172.71.26.37|172.71.26.37]] 12:35, 14 November 2024 (UTC)

== "{{diff|359134|On the off-chance...}}" ==

So, we need [[[[Header Text]]]], [[[[header Text]]]], [[[[HEADER TEXT]]]], [[[[hEaDeR TeXt]]]], [[[[hEaDeR tEXt]]]], [[[[heADer TExt]]]], etc, as well, do we?

The only reason it existed was because it was wrong-cased originally. Best not to multiply pages unnecessarily, and that one's an easy to delete mistake. (''If'' anyone actually gets around to it...) [[Special:Contributions/172.69.194.205|172.69.194.205]] 17:19, 11 December 2024 (UTC)

Talk:3019: Advent Calendar Advent Calendar

2024-12-03T14:04:03Z

172.69.194.204: Thanks

Would this basically be triangle numbers? So on Christmas Eve you would open 300 windows?[[User:Tommyds|Tommyds]] ([[User talk:Tommyds|talk]]) 16:01, 2 December 2024 (UTC)
:Yes and no. It's not 12 days of Christmas (as mentioned in the title text), so only the overall number of gifts are a triangle number; you open 30 windows on Christmas Day. The 12 days ref is key as the song generates more gifts if taken literally even in 12 days -- 78 on the last day, 66 on the previous day, etc, for a total of 364. [[User:Mneme|Mneme]] ([[User talk:Mneme|talk]]) 16:35, 2 December 2024 (UTC)

Notice that this year The Advent calendars are correct. Normally, Advent calendars start at the 1st of December even if the Advent starts at a different day. But this year the Advent also starts at the 1st of December. [[Special:Contributions/162.158.172.40|162.158.172.40]] 16:55, 2 December 2024 (UTC)

Donald Knuth wrote a paper for April 1984 Communications of the ACM that included an analysis of the complexity of 12 Days of Christmas. It's in the CACM archive https://dl.acm.org/doi/pdf/10.1145/358027.358042. {{unsigned ip|172.70.211.144|16:58, 2 December 2024 (UTC)}}

The explanation currently says "each day, he gets another advent calendar, which each contains 24-25 different items". I don't think that's correct; look at the picture: each day's calendar has one fewer item than the previous one. For example, the 24th only has 2 boxes and the 25th only has one. --[[User:Itub|Itub]] ([[User talk:Itub|talk]]) 17:25, 2 December 2024 (UTC)

Perhaps each smaller advent calendar might also contain a smaller advent calendar and so on ...? [[Special:Contributions/172.70.90.199|172.70.90.199]] 17:51, 2 December 2024 (UTC)
:Since the 1st has a calendar with a 1st, that would mean an infinite number of calendars just on the first day, so probably not. [[Special:Contributions/172.71.154.225|172.71.154.225]] 18:03, 2 December 2024 (UTC)
::It could work out if you don't open the first window of a new advent calendar on the day that it is revealed. So on day 1, you open the first window revealing an advent calendar that starts on day 2. Then on day 2 you open the second window, revealing a second advent calendar and the first window of the day 1 advent calendar, revealing a third advent calendar. ... and so on. If my mental math on that is right, it's doubling every day, so 2^24 =~ 16M calendars in total? (I could be off by a day) [[Special:Contributions/172.71.147.69|172.71.147.69]] 19:38, 2 December 2024 (UTC)

Can we just take a moment to appreciate whoever named the bot for this page? They wrote as follows: Created by 4 ENVELOPE BACKS 3 NERDS A-EDITING, 2 TURTLE BOTS, AND A FUNNY NEW XKCD. [[User:Willintendo|Willintendo]] ([[User talk:Willintendo|talk]]) 23:26, 2 December 2024 (UTC)
:That note is hand-edited on the first couple of edits. Not sure why that rule exists, though. [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 00:50, 3 December 2024 (UTC)

The title text says 'may' twice, "per day may may [sic] seem absurd" --[[Special:Contributions/198.41.236.163|198.41.236.163]] 00:01, 3 December 2024 (UTC)

The German YouTube channel "Malternativ" has actually done this a couple years: Opening one advent calendar every day. He went more and more insane as December went on… [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 00:50, 3 December 2024 (UTC)

Noting that the calendar is entirely correct for the day of publication. Too much to hope for that it is ''kept'' correct for each further day of Advent until (or, rather, 'until and including', as noted at least once above) Christmas Day? Maybe worth checking to see if (at an appropriate time, Randall-time, later today on the 3rd) it hasn't been updated. Or some special sub-page appeared with a revised (Time-like) update. Just in case. And, if Randall doesn't, I'm sure it's not beyond our own wit to make adjustments/animate as a fan-copy. [[Special:Contributions/172.70.91.214|172.70.91.214]] 01:57, 3 December 2024 (UTC)

[https://knowyourmeme.com/memes/xzibit-yo-dawg Yo Dawg], I herd you like advent calendars, so I put an advent calendar in your advent calendar so you can count down while you count down. [[User:Solomon|Solomon]] ([[User talk:Solomon|talk]]) 03:31, 3 December 2024 (UTC)

Wonder how many chocolates you would get if you did this with the life expectancy advent calendar. [[User:N-eh|N-eh]] ([[User talk:N-eh|talk]]) 04:40, 3 December 2024 (UTC)
:At some point, most people would reach the point at which that many chocolates would be a lethal (or at least LD50) quantity, so would be a self-shortening process. For those who reach the end of their LEAC ''without'' it actually being the cause of death, there should be a compensatory (or 'condolances') supply hidden on the back, for entirely guilt-free eating. [[Special:Contributions/172.70.162.200|172.70.162.200]] 06:01, 3 December 2024 (UTC)

Nobody tell Stuart and Dan about this one... [[Special:Contributions/172.71.183.11|172.71.183.11]] 06:56, 3 December 2024 (UTC)

I still don't understand it. Does he not open the first and second door of the second calendar on the second day? If not, does he open the first or the second door of the second calendar. Do the other items stay in the calendar? [[Special:Contributions/162.158.245.162|162.158.245.162]] 07:36, 3 December 2024 (UTC)
:Each next calendar has one fewer doors. So the second calendar starts with door number 2. On 1 December he opens the number 1 door revealing the first subcalendar, where he opens the number 1 door. On 2 December he opens the number 2 door of the first subcalendar and then the second door of the big calendar, revealing the second subcalendar, where he opens the first door, which is the number 2 door, since it has no number 1 door. [[User:Mtcv|Mtcv]] ([[User talk:Mtcv|talk]]) 08:12, 3 December 2024 (UTC)

Is the title correct, from a formal language point of view? I would have expected it to be Advent Advent Calendar. OTOH I'm not American and not overtly familiar with this tradition. {{unsigned ip|172.69.194.19|08:49, 3 December 2024}}
:A "<Foo> Advent Calendar" is an Advent Calendar that is themed for <Foo>. A "Dogs Advent Calendar" is probably themed with dog pictures (a "Dogs' Advent Calendar" might be themed ''for'' dogs, perhaps with dog-treats/-toys, and the "Dog's Advent Calendar" might be a regular (human) AC that you've gifted to your dog... hopefully one without chocolates!). A "Fine Whiskey Advent Calendar" might have sampler bottles of various fine malts (or just pictures of them... booo!).
:An "Advent Advent Calendar" would be just Advent-themed. Which is just a Advent Calendar (i.e. traditional, not particularly rethemed; or even rather pointedly traditionally-themed as a poke back against the commercialist subversion of Advent Calendering). "Advent" is not a modifier to "Calendar" that gives one of them little doors and pictures (and/or gifts), but is a thing for which an object ("Calendar") has been created as an accessory.
:This is an Advent Calendar whose schtick is Advent Calendars, thus is an Advent Calendar Advent Calendar. Which seems at least as good as any other theme I've seen. And it's the first time I've seen this. But, if there are at least 24 other examples, then obviously there's now a possibility of an Advent Calendar Advent Calendar Advent Calendar. [[Special:Contributions/172.69.194.185|172.69.194.185]] 13:57, 3 December 2024 (UTC)
::Thank you, it's very clear. I was indeed wrongly interpreting Advent as a modifier to Calendar. [[Special:Contributions/172.69.194.204|172.69.194.204]] 14:04, 3 December 2024 (UTC)

Talk:2935: Ocean Loop

2024-05-21T11:05:16Z

172.69.194.204:

The 'standard' and '2x' sized images had unexpected sizes, so a Trivia section has been automatically generated, and an imagesize parameter has been added (at half size) to render the image consistently with other comics on this website. --[[User:TheusafBOT|TheusafBOT]] ([[User talk:TheusafBOT|talk]]) 20:47, 20 May 2024 (UTC)

Is there anyway to get notifications when a new comic comes out? I'm always late to these 21:27, 20 May 2024 (UTC)Jush
:I believe that there may be a Twitter (or X, or Xwitter, whatever we're calling it out) announcement direct from Randall's account, but I don't use that myself. And, like me, you were here ''right as it came out'', more or less, so so don't worry too much. You ''could'' write your own BOT-like poller (various ways, but do at least considerately throttle it back to checking perbaps no more frequently than every 15 minutes, 'cos too many people doing that would be 'problematical'), if you can't find a push-notifying service that does most of the hard work for you (and a whole host of other subscribers). [[Special:Contributions/172.70.85.241|172.70.85.241]] 22:23, 20 May 2024 (UTC)
:You can use the RSS feed: https://xkcd.com/rss.xml [[User:Val|Val]] ([[User talk:Val|talk]]) 04:07, 21 May 2024 (UTC)

Happy Victoria day to anyone else in Canada! [[Special:Contributions/162.158.146.235|162.158.146.235]] 21:39, 20 May 2024 (UTC)

Due to not being told about any Edit Conflict, I managed to co-edit the initial explanatuon with A.N.Other (sorry, haven't checked who, probably the first major editor in the page-history). I've put the most useful bit (IMO) of their article into mine, but some of it seemed wrong. Or at least not right.
*"because of the size and speed of a cruise ship, the ship likely wouldn't make it around the loop without falling off" - well, given the mass of water nicely holding itself to the loop, a ship floating around in it at the same speed would be holding itself to the loop quite nicely (moreso, perhaps, with its CoG taking a tighter loop than the fluid-loop).
**Of course, it could be slower, but that would mean fighting the current. Whatever huge velocity the water is going, you'd have to be capable of going full-reverse at ''significant'' speed to overcome that,
***Well, you could be ''just'' less than the ''just'' more than fast-enough water, but it's probably significantly faster than loop-speed, or a lot of edge-surface water would shed out of the topmost loop-trough due to fluidic friction against the trough itself.
***And there's the acceleration needed to match the fluid flow-rate, but that causes problems before 'falling off' is an issue. Imagine suddenly finding yourself going hundreds (thousands?) of knots sternwards in still water. Probably what it'd feel like, before even getting to the tilt (by which time, any ship that had survived is probably now close to water-speed).
*"Second even if they managed to make it through without falling, many of the passangers would abtain extreme injuries and/or likely fall off the ship all together (unlike {{w|rollercoasters}} the passengers aren't strapped down)" - If you experience negative Gs in a rollercoaster, it's not a true loop (just an awkward inversion). You should normally always stay at positive Gs, albeit at somewhere within 0<Gs<1 (which ''feels'' like negative, but is just short of weightlessness). Being strapped in is still important, but mostly for forces lateral to "local down" for where you are on the ride.
**...or, of course, if the ride malfunctions and leaves you stationary and inverted. Which happens, but that's not at all intended in most situations. There'd be no way an 'otherwise normal' flume-loop would do that, though refering back to the need of your ship to experience initial acceleration before it even hits the loop (and final deceleration once it exits it).
*"Third, because of the way the loop's designed, several hundreds (if not thousands) of tons of water is being launched onto the top of the cruise ship at a high speed. Needless to say, this would not only likely capsize the ship, but would also flatten any passenger on the deck." - The sudden undersea current is going to be a problem, but it's not going to be directed over the ship (save ''completely'' over the ship, in the loop far above).
**What you'll have is the turbulent local sea conditions. There'd be a 'standing wave-trough' in front of the point the jet of water is shown to emerge, itself probably a catastrophic problem for a ship, even an ocean-going one built in expectation of occasionally meeting {{w|rogue waves}}) and all the problems involved in traversing such rough seas. If your vessel can survive that (without spinning sideways and hitting the flume-trough, or breaking its back due to the extremely uneven and changing buoyancy along its length) then it's probably going to survive the much smaller amount of water that splashes 'over' its upper superstructure, compared to whatever relative mastrom of flow there will be passing under/against its (nominally) below-waterline hull.
I don't know how much 'reality' Randall has invested in this premise (I presume little, given the lack of pressure-trough in the 'still' water just short of the jet-emergence, nor any distortion in the sea surface wherever the jet originally sucked its water in from), but a lot of the issues of the looping-the-loop "What if" train will be the prime factors, plus maintaining general control (in river navigation, going downstream, between bridge piers, you really have to power your vessel forward, faster than the river itself, or risk losing yaw discipline on your craft). All the rest is icing on the cake of improbability. [[Special:Contributions/172.70.85.241|172.70.85.241]] 22:23, 20 May 2024 (UTC)
:It's a comic drawing after all, it's meant to illustrate the concept but leave the actual reality to our imagination. Conceptually it seems obvious to me that if the ship actually makes it through the loop, it exits fairly smoothly (class 2 or class 3 white water rafting).[[Special:Contributions/162.158.146.52|162.158.146.52]]
:"...wherever the jet originally sucked its water in from..." - from the mains, obviously.[[Special:Contributions/172.69.194.204|172.69.194.204]] 11:05, 21 May 2024 (UTC)

2932: Driving PSA

2024-05-14T10:35:33Z

172.69.194.204: /* Explanation */

{{comic
| number = 2932
| date = May 13, 2024
| title = Driving PSA
| image = driving_psa_2x.png
| imagesize = 414x538px
| noexpand = true
| titletext = This PSA brought to you by several would-be assassins who tried to wave me in front of speeding cars in the last month and who will have to try harder next time.
}}

==Explanation==
{{incomplete|Created by a CLUELESS BOT DRIVING AT 72.42048 km/h (20.1168 m/s) - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
A PSA is a {{w|Public Service Announcement}}. Some drivers, when having priority (often informally called "right of way") by the rules of the road, will let others take it before them. This comic is saying that people who exhibit this behavior are actually {{w|The_Terminator|Terminator}}-style assassins, sent to kill people by sending them into oncoming traffic and making it look like an accident.

The title text explains that Randall made this PSA because he has experienced this multiple times in the last month. Since he believes this behavior to be the action of time-travel assassins, he has not accepted the right of way, and thus believes himself to have evaded death. He then says that, since he already knows this trick, the assassins should try harder. Such a claim that assassins are actively trying to murder him using "right of way" would be treated as a conspiracy theory by most people.

Despite the PSA's conspiratorial presentation, this is good advice. This habit is sometimes called "the wave of death", because it is common for such "generous" drivers to forget about other lanes that also have right-of-way over the crossing driver or pedestrian, and cluelessly wave them through right into the path of another car which is traveling at full speed. Always check for yourself that your way is clear, and if your view is blocked, sit tight. While Randall likely exaggerated this for comical effect, it could actually be helpful in making the advice more memorable and therefore more likely to save lives.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Driving PSA:
:Random drivers can’t grant you the right of way as a gift.
:[An H-road intersection with the main road going from top to bottom and the leading road coming from the left]
:[A car is parked to the right of the left road]
:Your car: You, waiting to turn left
:[A car is parked to the left side of the right main road, with another car, a truck hauling cargo, and a car lined up behind it]
:First car [in speech bubble]: You go ahead! I’m feeling generous.
:First car: Time traveler pretending to be polite
:[To the right of the line of cars is a black arrow pointing upwards, with text beneath it reading 45 MPH and a car behind the text]
:Clueless car: Car that they are waving you into the path of
:If someone waves you out, assume that they are an assassin sent from the future to kill you and make it look like an accident.

{{comic discussion}}

[[Category:Time travel]]

Talk:2919: Sitting in a Tree

2024-04-13T11:30:45Z

172.69.194.204:

Meh, they're just dropping burning pine cones on the wargs. [[User:BunsenH|BunsenH]] ([[User talk:BunsenH|talk]]) 04:06, 13 April 2024 (UTC)

I hope I did this right, seeing as this was my first ever edit! [[User:Name of User|Name of User]] ([[User talk:Name of User|talk]]) 04:15, 13 April 2024 (UTC)

Did Randall mean e-filing as in submitting your tax return on the web, and how is that more alarming than ironing sitting on a branch? Or is there some other meaning to efiling? [[Special:Contributions/172.68.243.77|172.68.243.77]] 06:46, 13 April 2024 (UTC)
:Could be that they're sitting in a ''data tree'', selectively traversing it to find [[2918: Tick Marks|a fraudulent subset of transactional records]] to 'declare'... [[Special:Contributions/141.101.99.74|141.101.99.74]] 10:18, 13 April 2024 (UTC)

So, "whaling" can mean hitting (usually in the form "whaling on"), but "whaling" also means spending a lot of money, such as when gambling or in a video game. {{unsigned ip|172.71.222.210|11:05, 13 April 2024}}
:Personally, I just automatically thought they would be ''actually'' hunting marine mammals![[[731: Desert Island|''cetacean]] [[1402: Harpoons|needed'']]] [[Special:Contributions/172.69.194.204|172.69.194.204]] 11:30, 13 April 2024 (UTC)

290: Fucking Blue Shells

2024-03-18T15:24:30Z

172.69.194.204: /* Explanation */ Streamlined markup

{{comic
| number = 290
| date = July 16, 2007
| title = Fucking Blue Shells
| image = fucking_blue_shells.png
| titletext = You can evade blue shells in Double Dash, but it is deep magic.
}}

==Explanation==

Sometimes, something suddenly goes wrong, and you can only shout obscenities at it. For instance, when the dog bites, when the bee stings, something unexpected happens, or a program crashes (e.g. a {{w|Segmentation fault|segfault}}), the victim often reacts by swearing.

For [[Randall]], however, profanities are caused mostly by {{w|blue shell}}s in the video game {{w|Mario Kart}}. The blue shells, when fired, target the player currently in first place and stop them cold. In a close game near the end of the race, a player can go from first to an unrecoverable last in one hit.

The title text refers to {{w|Mario_Kart:_Double_Dash!!|Mario Kart: Double Dash}}. This includes a technique to avoid being hit by a blue shell, but it requires skillful timing to accomplish. The term "{{w|deep magic}}" comes from computer programmer slang. Interestingly, with a boost mushroom in Mario Kart Wii and Mario Kart 8 (and the so-called "Super-Horn" in the latter), it is also possible (with accurate timing) to escape blue shells.

==Transcript==
:My Profanity Usage By Cause:
:[A pie chart is shown.]
:[Injury is about 2.5% of pie chart.]
:[Irony is about 2.5% of pie chart.]
:[Misc is about 2.5% of pie chart.]
:[Segfaults is about 10% of pie chart.]
:[Mario Kart is about 82.5% of pie chart.]

{{comic discussion}}
[[Category:Pie charts]]
[[Category:Comics with color]]
[[Category:Video games]]
[[Category:Mario Kart]]

2835: Factorial Numbers

2024-03-15T19:02:43Z

172.69.194.204:

{{comic
| number = 2835
| date = September 29, 2023
| title = Factorial Numbers
| image = factorial_numbers_2x.png
| imagesize = 628x481px
| noexpand = true
| titletext = So what do we do when we get to base 10? Do we use A, B, C, etc? No: Numbers larger than about 3.6 million are simply illegal.
}}

==Explanation==
A {{w|factorial}} is a product of positive integers. For instance, four factorial, written '4!', means 4×3×2×1=24.

The "base" of a numbering system defines which numbers it uses as digits and what each place value in a number means. For example, in decimal numbers (base 10), the digits go from 0 to 9, and place values are ones, tens, hundreds, etc. So "137" means 1×100 + 3×10 + 7×1 = 137. Numbers can also be written in other bases, such as binary (base 2, using the digits 0 and 1 and place values of 1, 2, 4, 8...) or octal (base 8, using the digits 0-7 and place values of 1, 8, 64, and so on). Using different bases is uncommon, but is sometimes useful in computer science.

In the comic, [[Cueball]] proposes a {{w|factorial number system}}, where the base ''changes'' for each place value - the first digit can be 0 or 1, the next digit can be 0, 1, or 2, the third can be 0, 1, 2, or 3, and so on. Each place value is the factorial of the base. So the number 137 in base 10 could be written as 10221, meaning 1×5! + 0×4! + 2×3! + 2×2! + 1×1!. While this numbering system is technically usable and can express any number, it seems excessively complicated, and the only reason Cueball gives for using it is that he thinks large digits like 9 should only be used in vast numbers (9 would not be used unless the number was at least 9 digits long, or over 3.2 million in decimal). This is a silly reason for using a new numbering system,{{cn}} so the math department thinks this is a prank, and has security throw him out.

In the title text, someone points out that a factorial number system needs more and more digits for each place value. The tenth digit in a factorial number would be in base 11, which needs 11 possible digits, and 0-9 only provides 10. In bases higher than 10, you can use letters to represent higher digits. For example, hexadecimal (base 16) goes from 0 to 9, then from A to F. It would be reasonable to do the same thing for higher bases in factorial numbers. Instead, Cueball says that it's simply illegal to write numbers larger than about 3.6 million, the largest you can go without using a base greater than 10. This is an absurd limitation, as other numbering systems can go as high as you like.

The number at the top of Cueball's presentation, 353011, is 3×6! + 5×5! + 3×4! + 0×3! + 1×2! + 1×1! which gives the decimal value of 2835, the number of the comic.

Cueball's examples of numbers written in factored appear as sequences [https://oeis.org/A007623 A007623] in the OEIS.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon. - Still needs a lot of deconstruction/reconstruction work on the [Poster:] to make it properly Transcripted (no tables, ideally!), but have improved the surrounding markup/descriptions}}
:[Cueball is standing in front of a large poster. There are two uniformed officers (a Ponytail and a further Cueball, wearing badged hats) approaching Cueball.]
:[Poster:]

: Variable-base Factoradic™ numbers
:{|
|Base 7||Base 6||Base 5||Base 4||Base 3||Base 2
|-
|3||5||3||0||1||1
|}

: Left side

:{| class="wikitable"
|Base 10||Factoradic
|-
|1||1
|-
|2||10
|-
|3||11
|-
|4||20
|-
|5||21
|-
|6||100
|-
|7||101
|-
|
|-
|21||311
|-
|22||320
|-
|23||321
|}

: Right side

:{| class="wikitable"
|Base 10||Factoradic
|-
|24||1,000
|-
|25||1,001
|-
|
|-
|5,038||654,320
|-
|5,039||654,321
|-
|5,040||1,000,000
|-
|
|-
|999,998||266,251,210
|-
|999,999||266,251,211
|-
|1,000,000||266,251,220
|-
|1,000,001||266,251,221
|}

:Cueball: Small numbers like seven or nineteen shouldn't use big numerals like "7" or "9".
:Cueball: I mean, "9" is the biggest numeral we have! It should be reserved for '''''big''''' numbers.
:Cueball: Small numbers should be written with small numerals like "1" or "2".
:Cueball: That's why my variable-base system uses...Hey! No, listen!
:[Caption under the comic:] Factorial numbers are the number system that sounds most like a prank by someone who's about to be escorted out of the math department by security.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Characters with hats]]
[[Category:Math]]
[[Category:Self-reference]] 
[[Category:Comics featuring Ponytail]] 
[[Category:Multiple Cueballs]] 
[[Category:Popular Comics]]