explain xkcd - User contributions [en]

Talk:287: NP-Complete

2025-05-20T12:37:00Z

172.69.130.236:

;Unique deciphering requires unique pricetags
Shame this only works in restaurants that price all their appetizers differently. [[User:Davidy22|Davidy22]] ([[User talk:Davidy22|talk]]) 03:18, 13 October 2012 (UTC)
:Not necessarily because the NP-problem allows for any equivocally competing sum certifying how the total can be reached. Shared pricetags as well as a nonpositive would add degrees of freedom and make it impossible to rule out surprise deliveries even through exponential pretesting. Unless the waiter is running into the exponential worst case, the six waiting tables can be attended to immediately upon finding the first feasible combination: [[User:Roman Czyborra|Roman Czyborra]] ([[User talk:Roman Czyborra|talk]]) 15:44, 15 May 2014 (UTC)

;Trivial solution first found
I have a hunch that the seven fruit cups are pretty intentional as the first item on the menu and the simplest solution possible.
I was about to write a script to solve the problem through random selections and was going to optimize for speed by limiting the maximum times an item could be order to floor(15.05/price). Thus, one could order up to 2 sample plates, 3 moz sticks, 5 of the hot wings/side salad/french fries or 7 fruit cups without going over budget. (side note: you can always with these prices squeeze in a fruit cup with the exception of the 7 fruit cups). I found the "trivial" solution on the first step of the "preliminary" work for that script and then took a catnap.
Of course, since the nontrivial solution involves the same item as the trivial solution, one could just pick a number, multiply by that number, subtract one unit, and pick two other items, whose prices were not set yet, and adjust their prices to add up accordingly just to ensure both trivial and nontrivial solutions lest anyone actually write a program to solve the problem through brute force as oppose to through wit. Why seed? Because to not have a nontrivial solution would be so much like Blackhat.
Note to self: try this sometime in the real world using a real menu. [[User:Katya|Katya]] ([[User talk:Katya|talk]]) 02:17, 23 November 2012 (UTC)

;Traveling Salesman Problem
Note: Traveling Salesman Problem ''might'' be mentioned ''also'' because both this problem and the Knapsack problem to be solved belong to set of '''[[wikipedia:NP-complete|NP-complete]] problems'''; a Knapsack problem can be transformed in polynomial time to Traveling Salesman Problem, and solution of Traveling Salesman Problem can be transformed in polynomial time to Knapsack problem solution. --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 16:00, 11 December 2012 (UTC)
:Yes, indeed! I think both meanings are intended to fully get the joke. The <code>TSP:={(n,d,M)∈ℕ×({0…n}²→ℕ)×ℕ|∃c∈{1…n}ⁿ:{1…n}=⋃{cₙ|n∈{1…n}}∧∑{d(cₙ,c₍ₙ₊₁₎)|n∈{0…n}}<M}</code> can both help to timely attend to the six waiting tables and to reduce the <code>ORDERSUM:={(a,b)∈ℕ*×ℕ|∃c∈ℕ*:∑{cₙaₙ|n∈ℕ}=b}</code> problem to. Plus, the "as fast as possible" pun seems to allude to the again six ridiculous inputs any trained human will rearrange to a near-exact solution quicker than they are entered into a computer who can quickly exhaust this tiny search space for an exact solution: [[User:Roman Czyborra|Roman Czyborra]] ([[User talk:Roman Czyborra|talk]]) 15:44, 15 May 2014 (UTC)

;Trivial solution was not intended
In [http://www.maa.org/mathhorizons/MH-Sep2012_XKCD.html an interview] with the Mathematical Association of America Randall said that the trivial answer to this problem was a mistake. [[User:Xrays Knock Charms Down|Xrays Knock Charms Down]] ([[User talk:Xrays Knock Charms Down|talk]]) 03:00, 6 May 2013 (UTC)
:I added this very interesting info to the explanation - at first as a trivia, but then I realized that it would not be seen by everyone - as you often do not read below the transcript. Why would you, you do not need to see what was in the comic again... So I moved it up to the solution part, because to me it is a very important fact about this comic. An error by Randall... But Dgbrt keeps moving this info away from the solution. I have understood now that the trivia should be below the transcript - although I cannot see why this should be so - as I have just described. But who says that this info should be a trivia item? It was I who put it there (by mistake?) at first. I will try not to start an editing fight here, but still think there should at least be a mention in the explanation that it was a mistake - in case you do not realize there is a trivia section below. I have used this page a lot lately, and had not found out before, that it was always below. There is not that many pages with trivia sections [[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 11:02, 10 March 2014 (UTC)
::Cool reference, thanks! [[User:Roman Czyborra|Roman Czyborra]] ([[User talk:Roman Czyborra|talk]]) 15:44, 15 May 2014 (UTC)
:::How could Randall have missed that the '''first price''' was a solution, when drawing the strip? I know not everyone can do this kind of math in their head, but when I read the $15.05 and glanced over at the menu, that $2.15 was an even denominator of $15.05 was immediately apparent. I'm pretty sure that it'd be hard for him to miss, even if he actually has to use arabic notation to figure it out, which would take like three seconds. —[[User:Kazvorpal|Kazvorpal]] ([[User talk:Kazvorpal|talk]]) 16:23, 1 November 2019 (UTC)
::::Okay, reading the interview, all I can say is that this is a pitfall of taking longcut coding shortcuts. Speaking as a perl programmer, it'd take longer to write that algorithm than to quickly do at least the basic multiples of the prices in one's head, even if one has to do it through mental arabic notation (I have mental shortcuts I worked out before learning math notation in grade school, or in some cases simply "see" the answer).—[[User:Kazvorpal|Kazvorpal]] ([[User talk:Kazvorpal|talk]]) 16:28, 1 November 2019 (UTC)

;Complex solution found in a second
I was bored and tried to find a solution for fun. I found the more complex one quite fast by chance. It was actually the second combination I tried. I did not realize you could just add seven fruit cups because I was so set on starting with the sampler plate. Now I am not sure if I should be glad, because I was so lucky, or annoyed that my fight-the-boredom-idea did not work out, or even more annoyed that I never have that kind of luck in the lab where I could really use it for finding the one thing out of a thousand possible causes for "why-does-my-experiment-not-work" which actually will give me some usable data.
[[Special:Contributions/84.56.77.11|84.56.77.11]]

Did I find another solution or am I missing something (besides sleep)? I created a spreadsheet of prices and line totals and found a solution after 3 or 4 tries. Two mixed fruit, one mozarella sticks, and one BBQ sandwich. Once I found that, I realized the trival solution. Then saw in the explanation there are only two solutions but they didn't match mine with BBQ. Correct, no? Of course a general solution would be much more satisfying. [[User:ProfDigory|ProfDigory]] ([[User talk:ProfDigory|talk]]) 01:07, 10 July 2024 (UTC)
::BBQ sandwiches are not classified as appetizers, so that solution doesn't meet the criteria. [[Special:Contributions/172.69.130.236|172.69.130.236]] 12:37, 20 May 2025 (UTC)

;Not the knapsack problem
This explanation is thorough, and I like being thorough, but it seems to be a bit of overkill. I copy-edited it a bit, but I have a couple qualms. This is not really the knapsack problem, as it does not attach values to the items (as mentioned). It is more of a {{w|subset sum}} problem, which admittedly could be considered a variant of the knapsack problem. Secondly, I don't see why we need to go into detail about the movie Office Space. --[[User:Quicksilver|Quicksilver]] ([[User talk:Quicksilver|talk]]) 18:34, 22 August 2013 (UTC)
:I did some clean-ups, but the the "In computational complexity theory" still needs a review.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 20:19, 22 August 2013 (UTC)
::The Wikipedia article on {{w|Karp's 21 NP-complete problems}} hints that Karp originally defined <code>KNAPSACK:={(a,b)∈ℤ*×ℤ|∃c∈𝔹*:∑{cₙaₙ|n∈ℕ}=b}</code> closer to today's shape of <code>SUBSETSUM:={Z⊂ℤ|∃s⊆Z:∑s=0∧s≠∅}</code> than that of the Unbounded Knapsack Problem <code>UKP:={(v,w,V,W)∈ℤ*×ℤ*×ℤ×ℤ|∃c∈ℕ*:{∑{cₙvₙ|n∈ℕ},∑{cₙwₙ|n∈ℕ}}⊆{V…W}}</code> with the former via <code>Z:={b,-a₁…-aₙ,-2a₁…-2aₙ,…}</code> and the latter via <code>(v,w,V,W):=(a,a,b,b)</code> coming close enough to what we really need here, namely <code>ORDERSUM:={(a,b)∈ℕ*×ℕ|∃c∈ℕ*:∑{cₙaₙ|n∈ℕ}=b}</code>. So Randall did hit it bull's eye after all! [[User:Roman Czyborra|Roman Czyborra]] ([[User talk:Roman Czyborra|talk]]) 15:44, 15 May 2014 (UTC)

;NP Food
Inspired by this comic, somebody has actually created an ordering site which tries to give you an order from a restaurant in your area (US only I think) totalling a specific amount [http://www.np-food.com NP Food]. Worth including above? -- [[User:Copito|Copito]] ([[User talk:Copito|talk]]) 20:43, 8 November 2013 (UTC)

That site doesn't work for me. —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 10:07, 19 November 2013 (UTC)

:I do get more than nothing: a redirect to the HTTPS port whose certificate is signed only to .np-food.com without WWW and whose HTML and PNG and JS suggest that either solutions for San Francisco, Austin, Saint Louis, Miami, and New York menues have been memoized and that you may order by entering your credit card credentials or that only fools wait for a computer to calculate an NP-hard problem on too large a search space. [[User:Roman Czyborra|Roman Czyborra]] ([[User talk:Roman Czyborra|talk]]) 15:44, 15 May 2014 (UTC)

;Exhaustive Solution
[[user:Roman Czyborra|Roman Czyborra]] did post this at the explain:
;The Solution
… can be calculated as
let totaling total menu = if total == 0 then [[]]
else if total < 0 || null menu then []
else totaling total (tail menu) ++ map (
head menu :) (totaling (total - head menu) menu)
in totaling 1505 [215,275,335,355,420,580]
== [[215,355,355,580],[215,215,215,215,215,215,215]]
I don't think this is a helpful explain. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 19:11, 14 May 2014 (UTC)

Yes, I did.
Because I did think it was helpful.
Not just because an (effective if not efficient) general solution earns you a 50% on $15.05 tip.

Moreover to demonstrate that and how a complete search finds those two solutions.

And that the search tree can branch exponentially with each additional menu item.
Or with additional dollar bills to be spent.
Notwithstanding that any constructive proof of NP=P would let us replace this
straightforward bad NP-implementation with an equivalent better P-implementation.
Before Donald Knuth coined the name NP-Complete, the class was suggested to be named
'''PET''' for the (Probably(while NP?P)|(Proven(if NP>P)|Previously(if NP=P))) Exponential Time pet problems.

What is so confusing about the calculation?
The whole cent amounts instead of dollar floats?
My naming of variables?
Should <code>totaling</code> be renamed to <code>solutions</code> or <code>orders</code>?
Or <code>menu</code> to <code>menu_items</code> or <code>appetizers</code> or <code>pricetags</code>?
<code lang=haskell>
type Cents = Int
orders :: [Cents] -> Cents -> [ [Cents] ]
orders menu total =
total == 0 | [ [] ]
menu == [] | []
total < 0 | []
total > 0 | orders (tail menu) total ++ map (
head menu :) orders menu (total - head menu)

orders [215,275,335,355,420,580] 1505
== [[215,355,355,580],[215,215,215,215,215,215,215]]

calls menu total = if null menu || total < 1
then 1 else 1 + calls (tail menu) total +
calls menu (total - head menu)
calls [] 1505
== 1
calls [580] 1505
== 7
calls [420,580] 1505
== 25
calls [355,420,580] 1505
== 73
calls [335,355,420,580] 1505
== 181
calls [275,335,355,420,580] 1505
== 437
calls [215,275,335,355,420,580] 1505
== 1153
</code>
Or is it the committee language Haskell that is causing problems?
What other well-defined language would you formulate a general solution in?

:If anyone wants to implement this in Python: calculate in cents, use fixed-point arithmetic, or check if the absolute difference is under some tolerance, otherwise the 7 mixed fruit solution is missed. <tt>print(7 * 2.15 == 15.05)</tt> gives <tt>False</tt>.

Discussing all of this is helpful.
Leaving a "Thus" result without its afferent reasoning (and its deleted heading) is not, is it?
Cheers: [[User:Roman Czyborra|Roman Czyborra]] ([[User talk:Roman Czyborra|talk]]) 15:44, 15 May 2014 (UTC)

:Please let's keep this code at the discussion page. No common reader would understand; the explain is not only for programmers. I'm a programmer, knowing many languages like BASIC, Pascal, C, C++, Java, Bash, Perl... also HTML, JavaScript... RPG, Databases and SQL... and much more. And if you like to buy an IBM Power 8 I can tell you the proper configuration for your needs.
:But these details are not helpful to explain the comic. There is math that has to be explained. Findings on program codes do even not belong to a trivia section. Nevertheless it seems I have to take a closer look on Haskell, which is not used by many people. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:22, 15 May 2014 (UTC)

A 50% tip on a $ 15.05 order is not possible, is it? --[[Special:Contributions/108.162.231.186|108.162.231.186]] 21:08, 1 November 2014 (UTC)

If I were the waiter my response would, at best, be "I'll come back when you're ready to order". At worse it would probably involve burns. -Pennpenn [[Special:Contributions/108.162.250.162|108.162.250.162]] 04:27, 7 October 2015 (UTC)

---Easiest response: "Excellent, Sir. I'll raise the price of the french fries to $15.05 - [[User:Ruffy314|Ruffy314]] ([[User talk:Ruffy314|talk]]) 18:19, 21 November 2015 (UTC)

If we assume that "general solutions" implies that it's a polynomial-time solution, is a 50% tip $7.55, $500 000, or $500 007.55? [[User:Hppavilion1|Hppavilion1]] ([[User talk:Hppavilion1|talk]]) 02:32, 16 September 2017 (UTC)

;A similar situation in real life
Nobody would do that in real life, right? But look at http://www.numberphile.com/videos/43_nuggets.html . A guy orders 43 chicken nuggets, which come in boxes of 6, 9 and 20. It is also a Knapsack problem in a menu order. But in that case there is no solution.
:I tried solving what you described without of clicking the link (still didn't) and before reading the last sentence, and this one is very obvious and quick to find not solvable. As 43 is abviously not dividable by 3 (as one can see at first glance and which would be required to use only 9-boxes and 6-boxes) we need at least one 20-box. Leaving 23 nuggets. That's still not dividable by 3 so there is another 20-box, leaving us at 3 nuggets. Other approach sees that at first we need a package of 9, to get to an even number, and then 9-boxes can only be choosen in pairs at 18-boxes which is no benefit to 6-boxes, so it is only 6 and 20 left. 34 is not dividable by 3 and/or 6. So again subtracting 20 makes it 14, which is obvious to be unsolvable by using only 6-boxes. So "your" problem is quite more trivial. BTW: please sign your comments. --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 10:42, 24 June 2019 (UTC)

TSP is NP-hard, not NP-complete [[User:Tembrel|Tembrel]] ([[User talk:Tembrel|talk]]) 00:19, 14 November 2019 (UTC)

If you guys like the knapsack problem and simplified stuff, then I've got the game mod for you! https://steamcommunity.com/sharedfiles/filedetails/?id=1844662069 along with https://ktane.timwi.de/HTML/Simon%20Selects.html

(I also tried solving this like I would that mod, but then I realized that this problem is not that.) [[Special:Contributions/172.69.34.24|172.69.34.24]] 03:05, 18 July 2020 (UTC)

;On general solutions
The explanation seems to assume that general solutions must be in polynomial time, but the comic does not mention that. It seemed to me that finding a non-polynomial general solution (which exist, obviously, with one even described in the explanation) *still* gets a 50% tip, which also means the 50% tip is a lot more reasonable now. While mentioning that no polynomial GS exists is probably still a good idea, it seems to me that the explanation should not assume one is neccessary for the tip. [[Special:Contributions/172.68.238.109|172.68.238.109]] 00:59, 24 October 2022 (UTC)

330: Indecision

2024-10-24T01:04:58Z

172.69.130.236:

{{comic
| number = 330
| date = October 17, 2007
| title = Indecision
| image = indecision.png
| titletext = Hey, I don't make the rules. It's in the book.
}}

==Explanation==
These two friends (both presumably male, since female characters in [[xkcd]] are depicted with hair) are surprisingly cavalier in taking the suggestion to engage in sexual experimentation to alleviate boredom. Even if both men are gay, the fact that they're friends (as the rule in the book describes them) suggests that they are not currently having sex on a regular basis.{{citation needed}} In this case - and even more so if the friends are heterosexual - most people would not take the book's suggestion, and it may even make them feel embarrassed and awkward.{{citation needed}}

The book that one of the [[Cueball]]s grabs appears to be some sort of all-encompassing rule book, its reach including the social sphere. Obviously this book is fictional, but the line "I think there's a rule about this" sounds like a reference to folk "rules" or guidelines like the "{{w|five-second rule}}."

{{w|Crisco}} is a brand of shortening, a fat that is solid at room temperature and frequently used in baking, though is also sometimes used, as implied in this instance, as a sexual lubricant. Crisco was referenced again in a sexual context in the title text of [[414: Mistranslations]] and later as a part of a weird dream also in the title text of [[557: Students]].

The title text could be spoken by either one of the characters or [[Randall]]. It attempts to preempt any awkwardness or judgment the reader may have about this situation by transferring responsibility to the rule book.

==Transcript==
:[Cueball is lying on the floor with his friend.]
:Cueball: So what do you want to do?
:Friend: Still no ideas.
:Cueball: Wait, I think there's a rule about this.
:[Cueball goes to bookshelf and removes a book called "Rules".]
:[The book of rules is opened to the following:
:RULE social.b.99.1
:If friends spend more than 60 minutes deciding what to do, they must default to sexual experimentation.
:[Cueball is standing, holding the book. The friend is in the process of standing up.]
:Cueball: Huh.
:Friend: I did not know that rule.
:Cueball: Me neither.
:Friend: I'll go get the Crisco.

==Trivia==
A book suggesting a more or less unrelated solution that is accepted anyway is also pulled from a shelf in [[1024]].

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Homosexuality]]
[[Category:Sex]]

3001: Temperature Scales

2024-10-22T16:16:42Z

172.69.130.236: Spelling

{{comic
| number = 3001
| date = October 21, 2024
| title = Temperature Scales
| image = temperature_scales_2x.png
| imagesize = 740x535px
| noexpand = true
| titletext = In my new scale, °X, 0 is Earths' record lowest surface temperature, 50 is the global average, and 100 is the record highest, with a linear scale between each point and adjustment every year as needed.
}}

==Explanation==
{{incomplete|Created by an EXPONENTIAL TEMPERATURE SYSTEM. Do NOT delete this tag too soon.}}

Since the invention of the thermometer, a number of different temperature scales have been proposed. In modern times, most of the world uses {{w|Celsius}} for everyday temperature measurements, as it is part of the {{w|metric system}} that has been widely adopted for official uses. A small number of countries (namely Liberia, the USA and its three associated free states in the Pacific) retain the US customary (or 'imperial') system, which uses the ''slightly'' older {{w|Fahrenheit}} scale (°F was initially defined in 1724, the general current form of °C was created in 1743). The other widely used temperature scale is {{w|Kelvin}}, which uses the same scale as Celsius, but is rooted at {{w|absolute zero}}, making it both useful in scientific calculations and easy to convert to and from Celsius. Even in countries that use Fahrenheit regularly, scientific measurements are typically done in Celsius and/or Kelvin.

The strip proceeds to compare these scales, and a number of others, on a scaled of "cursed"-ness. The joke is highlighting how strange and generally difficult to use many older proposed systems were. All of the listed scales are real, but may be considered obsolete to varying degrees (though some, such as Rankine, are still sometimes used in legacy applications).

{| class=wikitable
! scope="col" | Unit
! scope="col" | Water Freezes
! scope="col" | Water Boils
! scope="col" | Notes
! scope="col" | Cursedness
! scope="col" | Explanation
|-
| {{w|Celsius}} || 0 || 100 || Used in most of the world || 2/10 || Celsius is defined (indirectly, these days, by way of comparison to Kelvin) so that the freezing and boiling points of pure water at standard atmospheric pressure are 0 and 100 degrees respectively. This (along with Kelvin) is considered the least cursed temperature system (at least from those where the ranking values make any sense), likely due to Randall's background. Notably it is still considered a 2/10, implying an inherent degree of cursedness for all systems.
|-
| {{w|Kelvin}} || 273.15 || 373.15 || 0K is absolute zero || 2/10 || Kelvin is a scientific unit of measure invented by {{w|Lord Kelvin}} that intends to use the same scale as degrees Celsius, but is offset by 273.15, in order to set the zero point at absolute zero (by way of using the {{w|Boltzmann constant}}, as of 2019). Kelvin and Celsius are, by far, the most common units used in scientific measurements and calculations. Their utility and inherent logic is likely what makes them the least "cursed".
|-
| {{w|Fahrenheit}} || 32 || 212 || Outdoors in most places is between 0–100 || 3/10 || Fahrenheit is officially used in several countries across the globe, and unofficially in several others. It was originally defined from the Rømer scale by multiplying its values by 4, recalibrating the scale for the melting of ice and body temperature{{actual citation needed}} and slightly changed the number for better divisibility. At this point, it was noticed that the boiling point of water seemingly became around 212 °F instead of the 256 it was supposed to be and redefined the scale so that the freezing point of water became exactly 32 °F and its boiling point exactly 212 °F. Despite this somewhat chaotic development and arbitrary fixed points, it gained usage, primarily in Anglophone countries, likely due to the scale being considered intuitively useful for some common functions (the range roughly matches the typical span of weather conditions, for various ranges of climate, and the 100 point is quite near normal human body temperature, even though 90 was initially presumed to be this). While it was largely displaced by the Celsius scale, the US (Randall's home country) continues to typically use it. It is ranked as slightly more cursed than Celsius.
|-
| {{w|Réaumur scale|Réaumur}} || 0 || 80 || Like Celsius, but with 80 instead of 100 || 3/8 || A historical French system used in some places until the early 20th century. In modern times mostly used in cheesemaking. The rating (3/8) is a joke on the boiling point of water in standard atmosphere being 80 instead of 100 as it is in Celsius; converting this to an out-of-ten scale would give 3.75/10, labelling it as more cursed than Fahrenheit but less so than Rømer.
|-
| {{w|Rømer scale|Rømer}} || 7.5 || 60 || Fahrenheit precursor with similarly random design || 4/10 || Created by the Danish astronomer Ole Christensen Rømer in around 1702, while the Fahrenheit scale was proposed in 1724.
|-
| {{w|Rankine scale|Rankine}} || 491.7 || 671.7 || An absolute scale, with 0°R set to absolute zero, but using the Fahrenheit scale. || 6/10 || Randall has shown disdain for this before, like in [[2292: Thermometer]]. The scale is mostly obsolete, but is still occasionally used in legacy industrial operations where absolute temperature scales are required.
|-
| {{w|Newton scale|Newton}} || 0 || 33-ish || Poorly defined, with reference points like "the hottest water you can hold your hand in" || 7-ish/10 || Created by Isaac Newton, measuring "degrees of heat". The rating (7-ish/10) is a joke about the vagueness of the scale's definition.
|-
| {{w|Wedgwood scale|Wedgwood}} || –8 || –6.7 || Intended for comparing the melting points of metals, all of which it was very wrong about || 9/10 || Created by potter Josiah Wedgwood in the 18th century. The measurement was based on the shrinking of clay when heated above red heat, but was found to be very inaccurate. Randall has a typo, as the scale is called Wedgwood (''without the e'').
|-
| Galen || –4? || 4?? || Runs from –4 (cold) to 4 (hot). 0 is "normal"(?) || 4/–4 || Galen, in his medical writings, is said to have proposed a standard "neutral" temperature made up of equal quantities of boiling water and ice; on either side of this temperature were four degrees of heat and four degrees of cold, respectively. The rating (4/–4) is a joke about the scale being defined between positive and negative 4, and could be interpreted as –100% cursedness.
|-
| {{w|Celsius#History|''Real'' Celsius}} || 100 || 0 || In Anders Celsius's original specification, bigger numbers are ''colder''; others later flipped it || 10/0 || As most scales' temperatures can be indefinitely large but there exists an absolute minimum temperature, defining the scale in this way (giving an absolute maximum but allowing indefinitely negative values) is indeed cursed, as nearly all possible temperatures will be negative. The rating (10/0) is a joke on the scale "flipping" the fixed points of modern Celsius. This might be interpreted as "infinitely cursed", or else just {{w|NaN|Not a Number}}.
The original logic was that zero could be easily calibrated to the height of a column of mercury at the temperature of boiling water, and further measurements then made of the amount it ''reduced'' in height under cooler conditions. This direction 'survives' in the historic {{w|Delisle scale}}, which predates (and arguably helped greatly inspire, though with a different factor) the classic version of °C. The version originally used by Anders was only 'corrected' posthumously, but nobody seemed bothered enough to do the same with Delisle's scale.
|-
| [https://physics.stackexchange.com/questions/459851/john-daltons-temperature-scale#459863 Dalton] || 0 || 100 || A nonlinear scale; 0°C and 100°C are 0 and 100 Dalton, but 50°C is 53.9 Dalton || 53.9/50 || {{w|John Dalton}} proposed a logarithmic temperature scale. The scale is defined so that absolute zero is at negative infinity, with the exponent chosen to match Celsius at 0 and 100. While Dalton temperature is defined for all positive and negative numbers, the nonlinear scale is difficult to work with since the amount of heat represented by a change of one degree Dalton is not constant. Degrees Dalton differs from Celsius by as much as 3.9 degrees between 0 and 100, but diverges much more for more extreme temperatures.

The rating (53.9/50) is a joke about the unit, as 53.9 Dalton would be 50 degrees Celsius — i.e. the cursedness could be understood as 50/50 (or 10/10, entirely cursed), but perhaps instead as 107.8% (even more than entirely cursed).
|-
| °X ([[Randall]]'s new temperature scale as defined in the title text) || 41.9 || 154.4 || Title text: "In my new scale, °X, 0 is Earths' record lowest surface temperature, 50 is the global average, and 100 is the record highest, with a linear scale between each point and adjustment every year as needed." || ∞ (estimated) || Usually temperature records are measured 1 m above ground as surface temperatures can be much higher. It is uncertain if Randall actually meant surface or just normal temperature records as the ones mentioned here.

The record lowest temperature on Earth is –89.2°C (–128.6°F), recorded at the {{w|Vostok Station|Vostok Research Station}} in Antarctica on July 21, 1983. This would then be set to 0°X unless it is surface temperature instead.

The {{w|List_of_weather_records#Highest_global_average_temperature|hottest ever average temperature of Earth}} as of 2024 is 17.16°C (62.9°F.) on 22 July 2024. [https://wmo.int/media/news/earth-experiences-warmest-day-recent-history][https://www.carbonbrief.org/state-of-the-climate-2024-now-very-likely-to-be-warmest-year-on-record/][https://climate.copernicus.eu/new-record-daily-global-average-temperature-reached-july-2024]. However it is the average temperature not the record temperature that should be used. This would then be set to 50°X but the question is if this should change on a daily basis or depend on a yearly average? But definitely not the highest ever average that should be used. Also again this is not the average surface temperature.

The {{w|Highest temperature recorded on Earth|record highest temperature}} is 56.7°C (134.1°F), recorded on July 10, 1913 at {{w|Furnace Creek, California|Furnace Creek Ranch}} in Death Valley, California. This is though disputed and 54°C (129.2 °F) seems a more reasonable record, which has been recorded more than once in recent years. This would then be set to 100°X unless it is surface temperature instead. Surface temperatures on the ground of up to 90°C has been recorded, in {{w|Furnace_Creek,_California#Climate|Furnace Creek up to 94°C}} (201°F).

{{cot|Derivation}}
To break the scale into two linear parts (below and above 17.16°C), we define two separate equations for each range:

1. Below 17.16°C (from –89.2°C to 17.16°C):
* 0 °X corresponds to –89.2°C
* 50 °X corresponds to 17.16°C

We calculate the slope m₁:

<center>m₁ = (50 – 0) / (17.16 – (–89.2)) = 50 / (17.16 + 89.2) = 50 / 106.36 ≈ 0.47</center>

Now, using the point (17.16°C, 50 °X), we calculate the intercept b₁:

<center>50 = 0.47 × 17.16 + b₁</center>

<center>50 = 8.06 + b₁</center>

<center>b₁ = 50 – 8.06 = 41.94</center>

Thus, the equation for temperatures '''below 17.16°C''' is:

<center>'''X = 0.47 × C + 41.94'''</center>

2. Above 17.16°C (from 17.16°C to 56.7°C):
* 50 °X corresponds to 17.16°C
* 100 °X corresponds to 56.7°C

We calculate the slope m₂:

<center>m₂ = (100 – 50) / (56.7 – 17.16) = 50 / 39.54 ≈ 1.26</center>

Now, using the point (17.16°C, 50 °X), we calculate the intercept b₂:

<center>50 = 1.26 × 17.16 + b₂</center>

<center>50 = 21.63 + b₂</center>

<center>b₂ = 50 – 21.63 = 28.37</center>

Thus, the equation for temperatures '''above 17.16°C''' is:

<center>'''X = 1.26 × C + 28.37'''</center>

;Freezing and Boiling Points

Freezing point of water (0°C): Since 0°C is below 17.16°C, we use the equation X = 0.47 × C + 41.94:

<center>X = 0.47 × 0 + 41.94 = 41.94</center>

So, the freezing point is 41.9 °X.

Boiling point of water (100°C): Since 100°C is above 17.16°C, we use the equation X = 1.26 × C + 28.37:

<center>X = 1.26 × 100 + 28.37 = 126 + 28.37 = 154.37</center>

So, the boiling point is 154.4 °X.
{{cob}}
See also [[2701: Change in Slope]].

Since extreme temperature records are being broken frequently due to {{w|climate change}}, this scale will need to be recalibrated regularly. Because it's not consistent over time, this makes it infinitely cursed.
|}

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

:Temperature Scales

:[A table with five columns, labelled: Unit, water freezing point, water boiling point, notes, cursedness. There are eleven rows below the labels.]

:[Row 1:] Celsius, 0, 100, Used in most of the world, 2/10
:[Row 2:] Kelvin, 273.15, 373.15, 0K is absolute zero, 2/10
:[Row 3:] Fahrenheit, 32, 212, Outdoors in most places is between 0–100, 3/10
:[Row 4:] Réaumur, 0, 80, Like Celsius, but with 80 instead of 100, 3/8
:[Row 5:] Rømer, 7.5, 60, Fahrenheit precursor with similarly random design, 4/10,
:[Row 6:] Rankine, 491.7, 671.7, Fahrenheit, but with 0°F set to absolute zero, 6/10
:[Row 7:] Newton, 0, 33-ish, Poorly defined, with reference points like "the hottest water you can hold your hand in", 7-ish/10
:[Row 8:] Wedgewood, –8, –6.7, Intended for comparing the melting points of metals, all of which it was very wrong about, 9/10
:[Row 9:] Galen, –4?, 4??, Runs from –4 (cold) to 4 (hot). 0 is "normal"(?), 4/–4
:[Row 10:] ''Real'' Celsius, 100, 0, In Anders Celsius's original specification, bigger numbers are ''colder''; others later flipped it, 10/0
:[Row 11:] Dalton, 0, 100, A nonlinear scale; 0°C and 100°C are 0 and 100 Dalton, but 50°C is 53.9 Dalton, 53.9/50

{{comic discussion}}

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