explain xkcd - User contributions [en]

349: Success

2014-01-13T13:29:56Z

173.245.53.117: added Category:Computers

{{comic
| number = 349
| date = November 26, 2007
| title = Success
| image = success.png
| titletext = 40% of OpenBSD installs lead to shark attacks. It's their only standing security issue.
}}

==Explanation==
{{incomplete|It's not just a comment on BSD, it only uses BSD to illustrate how standards can quickly slip}}

This comic is a comment on the difficulty of installing {{w|OpenBSD}}, which is taken to ridiculously (and amusingly) extreme levels, where Cueball and Megan somehow ''literally'' end up in deep water over the installation. OpenBSD is an {{w|open source}} {{w|Unix}} {{w|operating system}} which, like some other Unix variants, is often regarded as difficult to install and configure correctly, especially on home desktops with less common hardware profiles, and especially compared with the more popular Windows operating system.

It segues into this joke using the framework of a project that's fallen victim to poor preparedness, time management, and care. Managers of such projects have a tendency to cut corners and eliminate requirements formerly thought to be essential, just to ship the project and be able to report it as a success.

The title text is a reference to OpenBSD's premium on security. For a time, their slogan was ""Five years without a remote [security] hole in the default install!"; this was eventually changed to "Only two remote holes in the default install, in a heck of a long time!".

==Transcript==
:As a project wears on, standards for success slip lower and lower.

:0 hours
::[Megan looking at man working on the computer.]
::Cueball: Okay, I should be able to dual-boot BSD soon.

:6 hours
::[Cueball on the floor fiddling with the open tower in front of him.]
::Cueball: I'll be happy if I can get the system working like it was when I started.

:10 hours
::[Cueball standing in front of the computer which now has a laptop plugged into the tower.]
::Cueball: Well the desktop's a lost cause, but I think I can fix the problems the laptop's developed.

:24 hours
::[Cueball and Megan swimming in the sea, island and beach seen in the distance.]
::Cueball: If we're lucky, the sharks will stay away until we reach shallow water.
::Megan: If we make it back alive, you're never upgrading anything again.

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Computers]]

Talk:915: Connoisseur

2013-12-05T14:47:19Z

173.245.53.117:

This is one of those xkcd comics that I'm just constantly linking back to as an image retort. I love Randall. '''[[User:Davidy22|{{Color|#707|David}}y²²]]'''[[User talk:Davidy22|<tt>[talk]</tt>]] 01:28, 17 April 2013 (UTC)

I expanded the explanation and removed the incomplete tag. [[Special:Contributions/173.245.53.117|173.245.53.117]] 14:47, 5 December 2013 (UTC)

915: Connoisseur

2013-12-05T14:46:31Z

173.245.53.117: /* Explanation */

{{comic
| number = 915
| date = June 22, 2011
| title = Connoisseur
| image = connoisseur.png
| titletext = Our brains have just one scale, and we resize our experiences to fit.
}}

==Explanation==
[[White Hat]] is fond of good wine, and he can
distinguish slight differences in different types of wine.
On the other hand, [[Cueball]] doesn't mind a kind of wine or another,
all of them taste the same for him.
When White Hat tells Cueball that he should pay more attention
to types of wine, Cueball answers that wine is not different than
anything else in this respect, and chooses pictures of
{{w|Joe Biden}}, {{w|Vice President of the United States}},
eating a sandwich as an example.

In the last panel, apparently White Hat and Cueball are actually
running an experiment to see if people will concentrate on
slight differences among pictures of Joe Biden eating a sandwich,
jus in the same way that White Hat concentrates on
slight differences among kinds of wine.
The result of the experiment is clearly going to Cueball's side.

The title text present the same idea in a different wording.
The "scale of our brains" refers to a concept similar to
Richard Dawkins' {{w|Middle World}}, where things too small
(say, smaller than the point of a pin) or too big (bigger than
what we can see from a mountaintop) are just out of our
comprehension, so the things our brains understand must be
neither too small nor too big, i.e. the "middle world".

However, the title text goes further in this idea:
when we find things too big (like the distance to the Moon),
we shrink it so that it fits into the "middle world" we're used to.
Conversely, when we find things too small (say, a mote of dust),
we expand it for the same reason.
In a quite similar way, if all we have is pictures of Joe Biden
eating a sandwich, we "resize" that subject so that we can fill books
with the details about the pictures.

==Transcript==
:[White Hat is standing with Cueball. They each hold a wine glass in one hand, White Hat is holding a bottle of wine in the other. He looks at the label.]
:White Hat: How do you stand this cheap wine?
:Cueball: Wine all tastes the same to me.

:[Close-up of White Hat.]
:White Hat: You've just never had ''good'' wine. If you paid more attention, you'd realize there's a whole world here.

:[Close-up on the other man, who spreads his arms, sloshing his wine slightly.]
:Cueball: But that's true of ''anything!'' Wine, house music, fonts, ants, Wikipedia signatures, Canadian surrealist porn—
:Cueball: Spend enough time with any of them and you'll become a snobby connoisseur.

:[This panel has no border and is next to but aligned further down than the first three panels.]
:[The full frame of the two characters again. White Hat now has the bottle at his side.]
:White Hat: But some things do have more depth than others.
:Cueball: If you locked people in a box for a year with 500 still frames of Joe Biden eating a sandwich, by the end they'd be adamant that some were great and some were terrible.
:White Hat: You're exaggerating.
:Cueball: Oh yeah?

:[This panel is below the others, and is indented about a third of the way to the right. It is wide.]
:A YEAR LATER:
:[A box. Voices emanate from inside.]
:Voice #1: Sure, most closed-mouth frames are boring, but in #415, the way the man's jaw frames the mayo on his hand is pure perfection, and—
:Voice #2: What a surprise- ''you'' praising a mayo frame. Listening to you, I'd think there was nothing else in The Sandwich. Frankly, the light hitting J.B.'s collar through the lettuce would put #242 in my top ten even if he had ''no'' mayo on his hand at ''all''.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring White Hat]]
[[Category:Politics]]

Talk:998: 2012

2013-12-05T10:11:45Z

173.245.53.117:

2012 is almost over, and no end of the world yet. Makin' progress. [[User:Davidy22|Davidy22]][[User talk:Davidy22|<tt>(talk)</tt>]] 02:08, 13 November 2012 (UTC)
: We have until Winter Solstice, it seems, whereupon we face a calamity the likes of which haven't been seen since Y2K. -- [[User:IronyChef|IronyChef]] ([[User talk:IronyChef|talk]]) 06:33, 20 November 2012 (UTC)

I haven't been this disappointed by the apocalypse since Y2K. Not even worth a rental. [[Special:Contributions/69.127.136.211|69.127.136.211]] 03:51, 24 January 2013 (UTC)

Upgraded to past tense. [[User:Alpha|Alpha]] ([[User talk:Alpha|talk]]) 20:32, 23 February 2013 (UTC)

The Mayan did not predict the end of the world, they just would have to use a new calendar.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 19:56, 31 July 2013 (UTC)
:That's what the explanation says... why the incomplete/incorrect tag? [[Special:Contributions/173.245.53.117|173.245.53.117]] 10:11, 5 December 2013 (UTC)

Talk:998: 2012

2013-12-05T10:11:15Z

173.245.53.117:

Talk:1299: I Don't Own a TV

2013-12-05T09:54:05Z

173.245.53.117:

Annual Data for households between 1958-1970
http://www.tvhistory.tv/Annual_TV_Households_50-78.JPG

Plotted next to a fitted logarithmic function
http://imgur.com/aVWmQ9z

The negative second derivative of this function
http://imgur.com/xywpEJZ

If someone can find more data for television ownership I'd love to see it :) {{unsigned ip|‎173.245.54.12}}

Can someone explain why Randall believes smugness at not owning a television is decreasing? [[Special:Contributions/199.27.128.138|199.27.128.138]] 08:31, 4 December 2013 (UTC)

Because as TVs become less relevant, people don't feel smug for not owning one. [[Special:Contributions/141.101.99.216|141.101.99.216]] 11:44, 4 December 2013 (UTC)

;Current explanation - logistic curve

The current explanation is total bullshit. The thing with the negative second derivative is just saying, that the more embarrased people are, the more the change of the TV ownership rate will increase, which just means, more and more people will get themselves TVs.
The other point of view is, the more smug you will look like for not owning a TV, the more the change of the TV ownership rate will decline, which means, that less and less people are buying TVs.

It has nothing to do with a logistic curve. The function, which second derivative is depicted in this comic is totally irrelevant.

[[Special:Contributions/108.162.231.19|108.162.231.19]] 08:34, 4 December 2013 (UTC)

I have the strong feeling he is talking about a sine wave, not a logistic function. It fits the curve in the comic as well as the condition of f"=-f.
Also, it makes way more sense for the smugness to behave like this over time as for the first 30 years TV is culturally extremely significant and you therefore would want to own one in order to participate. But with declining quality of television and the emergence of the internet you might feel as if you were extremely progressive by not owning one anymore.

[[Special:Contributions/108.162.254.189|108.162.254.189]] 09:25, 4 December 2013 (UTC)

Yes, it definitely could be a sine curve. (see: [http://www.wolframalpha.com/input/?i=d%5E2%2Fdx%5E2%28sin%28x%29%29 http://www.wolframalpha.com/input/?i=d%5E2%2Fdx%5E2%28sin%28x%29%29]). If one would neglect the beginning of the function for simplicity, this could be a solution.

[[Special:Contributions/108.162.231.19|108.162.231.19]] 10:07, 4 December 2013 (UTC)

We bid a tearful farewell to our friend the line break. [[Special:Contributions/141.101.99.216|141.101.99.216]] 11:50, 4 December 2013 (UTC)

http://www.wolframalpha.com/input/?i=sin%283*pi*x%2F100%2Bpi%2F2%29+from+1945+to+2014 [[User:Xhfz|Xhfz]] ([[User talk:Xhfz|talk]]) 12:02, 4 December 2013 (UTC)

I agree with the commenter who said that the current explanation is bullshit, but I think he has the cause and effect reversed. Randall is saying that you feel more smug about not owning a TV as a result of observing how quickly TV ownership is becoming more or less trendy. In the 1950's, TV's were catching on quickly and becoming more popular, so you would feel embarrassed for not owning one. Later, the trendiness would start to decline as more people owned one, and you would head towards being smug. In the 2000s, people are giving up TVs because the internet makes them unnecessary. As this happens more and more, there's no point in feeling smug because you're no longer bucking a trend at all. --[[User:Kazim|Kazim]] ([[User talk:Kazim|talk]]) 12:49, 4 December 2013 (UTC)

In my view the title text joke is that smugness is defined as a function of TV ownership when in reality TV ownership is a function of smugness. [[User:Ralfoide|Ralfoide]] ([[User talk:Ralfoide|talk]]) 15:18, 4 December 2013 (UTC)

Hold on, the logistic curve gives very reasonable graphs both for ownership of TVs and for the negative second derivative. TV ownership easily fits a logistic curve, as it starts at zero and has to approach some upper limit. The negative second derivative has a very similar shape to the graph in the comic. Here's Wolfram|Alpha for the negative second derivative of a generic logistic curve: <http://www.wolframalpha.com/input/?i=-%28+d%2Fdx+d%2Fdx+%28100%2F%281%2Be%5E-%28.1x%29%29%29%29>. This would suggest that as time goes to infinity, people's feelings about TV ownership approach neutral; they do not oscillate like a sine function. This makes sense, because for the negative second derivative to be a sine function, TV ownership would have to be too, yet TV ownership is unlikely to be periodic. [[Special:Contributions/173.245.55.229|173.245.55.229]] 16:28, 4 December 2013 (UTC)

I have two issues with this explanation: the first is that it's too long to comfortably read, and I don't think the comic content merits such a long explanation. The other is that it reads too complexly. The point of this wiki is to make xkcd accessible for everyone, but it talks about things like sine waves, oscillation and convergence, which not all readers are going to grok. --[[User:Mynotoar|Mynotoar]] ([[User talk:Mynotoar|talk]]) 17:24, 4 December 2013 (UTC)

If we're keeping the explanation surrounding the area of "People therefore discussed television programs frequently, as a major social activity.", it maybe ought to be pointed out that major social discussions about TV programmes dropped off as a result of the increase in the number of TV channels and thus (except for ''particularly'' notable ratings-grabbers) the question of "Did you see what was on TV last night?" increasingly needed further qualifying. (However, I'm not sure this is revelevant.) Oh, and I've a feeling I should be feeling smug, right now. Absolutely gorge myself on radio, though. [[Special:Contributions/141.101.99.229|141.101.99.229]] 21:18, 4 December 2013 (UTC)

I do not see any evidence that this comic's title text refers in any way to a sine curve. If you consider a logistic function modeling TV ownership over time (which would look the similar to a logistic population growth model), you can take the function's second derivative, which vaguely resembles a sine curve, with the important difference that to the sides of the curve, the line becomes more level rather than repeating the curve. I would say the determining factors are the fact that the beginning of the graph is flat (as opposed to the curve just going to zero or showing the end of the previous curve), and the fact that he mentions the "negative second derivative of TV ownership rate," and the TV ownership rate would follow a model similar to a logistic population model, which is not a sine curve, though the second derivative of such a graph would, in fact, represent a sine curve. --[[User:Zweisteine|Zweisteine]] 21:36, 4 December 2013 (UTC)

Not sure if I'm coming in at the end of an edit war and pouring fuel on the argument, but I think the whole smugness/TV ownership / Programming comments are well made before the last paragraph. I'm confident that Randell's title text is a superficial comment about the shape of the graph. I've edited the last paragraph so there's no mention of sine waves, oscillation, convergence, or interpretation of where the graph starts or where it's going (that seems subjective to me). Just a link to what a "negative second derivative" is, and a statement that the comic resembles that chart. [[User:XQx|XQx]] ([[User talk:XQx|talk]]) 01:02, 5 December 2013 (UTC)

Except that graph does closely represent the second derivative graphs I've seen for graphs that start slow, rise suddenly, then level out again, like a population chart, or a chart showing TV ownership over time. [[User:Zweisteine|Zweisteine]] ([[User talk:Zweisteine|talk]]) 01:18, 5 December 2013 (UTC)

I think that, theoretically, something closer to an arctangent fits the number of televisions over time graph better than a logarithmic curve- at least if we consider some of the thousands of years during which nobody owned televisions. Linked below is a plot of arctan(x-2) + 1.3 and its negative second derivative (scaled to fit better in WolframAlpha's output window), the latter of which looks as much like the smugness graph in the comic as anything I've seen so far.
http://www.wolframalpha.com/input/?i=plot+atan%28x-2%29+%2B+1.3%2C+6%28x-2%29%2F%28x^2-4+x%2B5%29^2+for+x+%3D+0..4
--[[Special:Contributions/173.245.56.24|173.245.56.24]] 03:45, 5 December 2013 (UTC)

While the previous explanation of the title text involving the sine function was bogus (it's the second derivative of TV ownership rate, not the second derivative of smugness), the stuff about logistic (or arctangent or other sigmoid) functions is correct (if you believe that TV ownership should follow a sigmoid curve). I think that this can be explained, so I've put that in; hopefully, one can read it without the parentheses to get something understandable to lay folk, and then the parentheses show where Randall's mathematical jargon comes in. —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 04:59, 5 December 2013 (UTC)

The "this is incomplete because it needs further information" is not much of an explanation of what needs to be completed. It looks like the tag was added when the explanation was really, really poor and it't now obsolete. I would update it if I could figure out something that is still missing, but at this moment it looks like removing it altogether could be a better option. [[Special:Contributions/173.245.53.117|173.245.53.117]] 09:54, 5 December 2013 (UTC)

438: Internet Argument

2013-12-05T04:09:16Z

173.245.53.117: Aesthetic change in link about trolls

{{comic
| number = 438
| date = June 18, 2008
| title = Internet Argument
| image = internet argument.png
| titletext = It's easier to be an asshole to words than to people.
}}

==Explanation==
Since the first time the internet made possible
to have written conversations with people in remote locations,
it was found that most people tend to use harsh language
in these conversations much more often than they
would with regular spoken face-to-face conversations.
This effect is similar to what happens when people drive a car:
they're much more likely to get exasperated or angry
at other drivers than they would when not driving.

Also, some people (collectivelly known as {{w|Troll_%28Internet%29|Troll}}s)
find it funny to disrupt other people's conversations
(usually in internet forums), posing as innocent speakers.
Examples of this can be entering a conversation between
cancer patients suggesting the use of some "miracle" cure,
or just asking simple, obvious questions and then
pretending to not understand the answers.
Most probably, trolls wouldn't have this behavior
if they were speaking to a group of people in real life.
A similar concept is wikiterror, where someone
intentionally includes false information in Wikipedia
to see how long it lasts before someone notices.

In the first two panels, the two [[Cueball]]s are having
some harsh words (probably insults) between them.
[[Megan]] takes one of the Cueballs and flies him to the
other Cueball, so they see each other face to face.
In this situation, they both remain silent as none of them
finds anything to say to the other.

When Megan returns Cueball to his original computer,
both keep their conversation, but without the insults.

The title text just summarizes the whole idea into a single sentence.

==Transcript==
:[Cueball is typing profanities into his computer.]
:[Friend is typing profanities into his computer.]
:[Megan floats in behind Cueball.]
:[Megan lifts Cueball.]
:[They are flying over mountains.]
:[Megan and Cueball are floating in front of the friend and his computer.]
:[She sets Cueball down in front of the friend and his computer.]
:[Megan lifts Cueball again.]
:[They are flying.]
:[Megan sets Cueball down in his chair at his computer.]
:[Cueball is typing at his computer.]
:[Friend is typing at his computer.]

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]

Talk:438: Internet Argument

2013-12-05T04:07:23Z

173.245.53.117:

Last ever CRT monitor?[[Special:Contributions/89.243.117.162|89.243.117.162]] 20:52, 15 August 2013 (UTC)
:Yeah, I did try to start a category here, but it was deleted by an admin here.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:11, 26 August 2013 (UTC)

An explain on trolling is missing. Cueball is a {{w|Troll (Internet)|Troll}}.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:11, 26 August 2013 (UTC)

I've written a (hopefully) complete explanation, and removed the incomplete tag. I included an explanation for trolls, however I don't think this comic is about trolling. I think it's about how people who is friendly in daily life can be much harsher when there's not a face to be friendly to, but only a block of text. [[Special:Contributions/173.245.53.117|173.245.53.117]] 04:07, 5 December 2013 (UTC)

438: Internet Argument

2013-12-05T04:03:40Z

173.245.53.117: /* Explanation */

{{comic
| number = 438
| date = June 18, 2008
| title = Internet Argument
| image = internet argument.png
| titletext = It's easier to be an asshole to words than to people.
}}

==Explanation==
Since the first time the internet made possible
to have written conversations with people in remote locations,
it was found that most people tend to use harsh language
in these conversations much more often than they
would with regular spoken face-to-face conversations.
This effect is similar to what happens when people drive a car:
they're much more likely to get exasperated or angry
at other drivers than they would when not driving.

Also, some people (collectivelly known as [http://en.wikipedia.org/wiki/Troll_%28Internet%29 Troll]s)
find it funny to disrupt other people's conversations
(usually in internet forums), posing as innocent speakers.
Examples of this can be entering a conversation between
cancer patients suggesting the use of some "miracle" cure,
or just asking simple, obvious questions and then
pretending to not understand the answers.
Most probably, trolls wouldn't have this behavior
if they were speaking to a group of people in real life.
A similar concept is wikiterror, where someone
intentionally includes false information in Wikipedia
to see how long it lasts before someone notices.

In the first two panels, the two [[Cueball]]s are having
some harsh words (probably insults) between them.
[[Megan]] takes one of the Cueballs and flies him to the
other Cueball, so they see each other face to face.
In this situation, they both remain silent as none of them
finds anything to say to the other.

When Megan returns Cueball to his original computer,
both keep their conversation, but without the insults.

The title text just summarizes the whole idea into a single sentence.

==Transcript==
:[Cueball is typing profanities into his computer.]
:[Friend is typing profanities into his computer.]
:[Megan floats in behind Cueball.]
:[Megan lifts Cueball.]
:[They are flying over mountains.]
:[Megan and Cueball are floating in front of the friend and his computer.]
:[She sets Cueball down in front of the friend and his computer.]
:[Megan lifts Cueball again.]
:[They are flying.]
:[Megan sets Cueball down in his chair at his computer.]
:[Cueball is typing at his computer.]
:[Friend is typing at his computer.]

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]

Talk:828: Positive Attitude

2013-12-05T02:50:49Z

173.245.53.117:

What is an IV instrument? It has to be explained. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 20:58, 30 November 2013 (UTC)

I've rewritten all the explanation, expanding it a bit, adding the title text part and the IV explanation. So I've also removed the incomplete tag. Hope it can be now considered "complete". [[Special:Contributions/173.245.53.117|173.245.53.117]] 02:49, 5 December 2013 (UTC)

Talk:828: Positive Attitude

2013-12-05T02:49:42Z

173.245.53.117:

What is an IV instrument? It has to be explained. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 20:58, 30 November 2013 (UTC)

I've rewritten all the explanation, expanding it a bit, adding the title text part and the IV explanation.
So I've also removed the incomplete tag. Hope it can be now considered "complete". [[Special:Contributions/173.245.53.117|173.245.53.117]] 02:49, 5 December 2013 (UTC)

828: Positive Attitude

2013-12-05T02:48:07Z

173.245.53.117: /* Explanation */

{{comic
| number = 828
| date = December 1, 2010
| title = Positive Attitude
| image = positive attitude.png
| titletext = Having a positive attitude is almost tautologically good for your mental health, and extreme stress can hurt your immune system, but that doesn't mean you should feel like shit for feeling like shit.
}}

==Explanation==
[[Cueball]] feels bad because he's sick,
and his friend tells him to think positively
because that will make him feel better.
After thinking a bit Cueball notices that, following that reasoning,
if he feels bad it is his fault for being so pessimistic.
That makes him feel even worse as now he's not only sick,
but also feels guilty of his own sickness.

In the fourth panel, he throws away all the previous reasoning
and decides his mood is not the problem: the problem is that he's sick.
Also, he decides that whatever he feels now he'll finally get better
because he's treating his disease.

In the last panel
Cueball notices his last comment was actually optimistic,
so that makes him feel better.
At this point, it should be expected that Cueball's friend
would say "see? looking at things in an optimistic way
actually helps".
However, he puts optimism as something bad by using
the phrase "you suck at pessimism".
Cueball then tries to be optimistic at his "sucking"
by thinking he'll "be better at pessimism tomorrow".
Of course, being good at pessimism is something
he should avoid, as it was his very problem in the first panels.

The title text takes a serious turn, and acts as an advice for
people feeling bad for being sick.
The point is that sickness makes one feel bad enough by itself
without having to feel guilty for feeling bad when one's sick.

In the transcript, "IV" refers to {{w|Intravenous therapy}}.

==Transcript==
:[Cueball sits hunched with his knees drawn up to him on a hospital bed, hooked up to an IV. A friend stands by.]
:Cueball: I'm sick and I'm scared.
:Friend: Well, remember - having a good attitude is the most important thing. Think positively and you'll get better.

:[Darkness surrounds Cueball on the bed. The friend is off-screen.]
:Cueball: So if I'm sad or afraid or feel like crap sometimes, then...
:Friend: ...then if you don't recover, it will be ''your fault.''

:[Cueball clutches his hands to his face and leans back.]
:Cueball: Well that makes me feel even worse.
:Friend: See? You're doing this to yourself.
:Cueball: No!
:Friend: Stop it!
:Cueball: Argh!

:[Close up on Cueball, holding up his hand, pointing to himself.]
:Cueball: Okay, you know what? Screw this. My attitude isn't my problem. -- My ''disease'' is my problem, and I'm treating it. -- I'm going to be glum and depressed and pessimistic some days, and I'm going to '''''get better anyway.'''''

:[Cueball sits on the edge of the bed, his friend still standing in front of him.]
:Cueball: Wait, that ended up sounding optimistic.
:Friend: I guess you suck at pessimism.
:Cueball: Maybe I'll be better at it tomorrow.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Psychology]]

Talk:1292: Pi vs. Tau

2013-11-29T03:29:31Z

173.245.53.117:

I started an explanation. Hopefully others will help improve it, as I don't think it's quite adequate. [[Special:Contributions/199.27.130.174|199.27.130.174]] 05:32, 18 November 2013 (UTC)

The comic currently shows the symbol π (pi) in all three cases, but it should have the symbol τ (tau) in the rightmost case. I'm sure there is a compromise symbol "pau" too. Maybe with a deformed left leg? [[Special:Contributions/141.101.97.4|141.101.97.4]] 07:07, 18 November 2013 (UTC)

WolframAlpha gives
<pre>
4.5545743763144164456766617143366171162404440766665105335330776311513504520604364524762740226212061363100001776216741750712622557020442741544760057441760026766230424023460366047331305225241275347777145543054127636365666430221066167347236617261603127725745513663702031155234027041040155322217227723576660045156156303357534162372112340027743775672417274565277274565735325624457113522164166560115654407251403563246444122664066521461311773474046032763760765740133706761276420415672577471077133607673035331070364705651055376634161405567176532346433567731715723623721267302576735154761375545411215522177775706407470673020025353246535120744232706060324711633457720155013202527060250466252665661576165164140301645132275526153126363575631176312270212441433434206352313125326760006365710744276056412434626534152021052065172556442150110056601034116570607064550553636566432544260105637423220411372664024454234201642615033200331506013362432026775605543212342336511350621361642654426372425415023071413764173735461042064323757413414533013..._8</pre> which does indeed have four 666 sequences. [[Special:Contributions/141.101.99.254|141.101.99.254]] 08:06, 18 November 2013 (UTC)
This number contains 7777, 000 and 444 twice, though. [[Special:Contributions/141.101.93.11|141.101.93.11]] 09:08, 18 November 2013 (UTC)

Wrote the transcript, not sure if I explained the visual well enough, so I left the incomplete tag if someone else has a better idea. Should suffice for understanding however, considering the content [[Special:Contributions/108.162.248.18|108.162.248.18]] 08:55, 18 November 2013 (UTC)

----

(The discussion about different results was trimmed)

Wolfram gives the result with 666

http://www.wolframalpha.com/input/?i=1.5+pi+octal
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022
</pre>
The Unix arbitrary precision calculator gives the result without

$ echo "scale=200; obase=8; 6*a(1)" | bc -l
<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
Any suggestions how we can check them?

"Randall says so" is probably correct, but insufficient :-) {{unsigned|Mike}}

:Please use the <nowiki><pre></nowiki> tag for this long numbers.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 09:20, 18 November 2013 (UTC)

Testing Wolfram Alpha with <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8 in decimal</pre> and <pre>4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000_8 in decimal</pre> both indicate the approximation is only accurate to a limited degree.
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>
<pre>
http://www.wolframalpha.com/input/?i=4.55457437631441644567666171433661711624044407666651053353307763115135045206043645247627402262120613631000177621674175071262255_8+in+decimal
</pre>

The method I used to get the value I put in the text was; I used the following command to generate my approximation:
<pre>echo 'scale=200; obase=8; a(1) * 6' | bc -l | tr -d ' \\\n' ; echo</pre> which outputs<pre>
4.554574376314416443236234514475050122425471573015650314763354527003043167712611655054674757031331252340351471657646433317273112431020107644727072362457372164022043765215506554422014311615574251563446213636251744101107770257
</pre>
In 'bc'', a(1) is arctangent of 1 (i.e. 45 degrees, or pi/4); (pi/4 * 6) should be equal to 'pau'. I additionally checked the result using base 2 encoding, and converted each three bit binary value into an octal value. The decimal value of pi (using a(1) * 4) matches with the value of pi to at lease 1000 digits.
[[Special:Contributions/173.245.54.86|173.245.54.86]] 09:21, 18 November 2013 (UTC)

Both Maxima and the GNU Emacs calculator output as the first 1000 octal digits:
<pre>
4.5545743763144164432362345144750501224254715730156503147633545270030431677126116550546747570313312523403514716576464333172731124310201076447270723624573721640220437652155065544220143116155742515634462136362517441011077702611156024117447125224176203716336742057353303216470257662666744627534325504334506002730517102547504145216661211250027531716641276765735563341721214013553453654106045245066401141437740626707757305450703606440651111775270032710035521352101513622062164457304326450524432531652666626042202562202550566425643040556365710250031642467447605663240661743600041052212627767073277600402572027316222345356036301002572541750000114422036312122341474267232761775450071652613627306745074150251171507720277250030270442257106542456441722455345340370205646442156334125564557520336340223313312556634450170626417234376702443117031135045420165467426237454754566012204316130023063506430063362203021262434464410604275224606523356702572610031171344411766505734615256121034660773306140032365326415773227551
</pre>
This also agrees with the first 220 digits of the previous result (last two digits above are 57 vs 61 here, maybe due to rounding when converting to octal). Again, no 666 within the first 200 digits. The Wolfram result deviates from this at the 18th digit already. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 10:21, 18 November 2013 (UTC)

Also e+2 does not contain the substring '666':
<pre>echo "scale=200; obase=8; e(1) + 2" | bc -l</pre>
<pre>4.55760521305053551246527734254200471723636166134705407470551551265170233101050620637674622347347044466373713722774330661414353543664033100253542141365517370755272577262541110317650765740633550205306625</pre>--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 10:43, 18 November 2013 (UTC)

: A sudden flash of realization: are we getting nerd-sniped here?--[[Special:Contributions/108.162.254.168|108.162.254.168]] 11:55, 18 November 2013 (UTC)

::Not unlikely. Have posted this as a trivia. [[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 20:11, 23 November 2013 (UTC)

: The claim is clearly about e+2, making Dgbrt's comment closest to the right direction. [[Special:Contributions/173.245.54.40|173.245.54.40]] 12:03, 18 November 2013 (UTC)

When I take Wolfram alpha's octal(pi*1.5) I get the first 303 (base 10) characters as this:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777714554305412763636566643022106616734723661726160312772574551366370203115523402704104015532221722772357666
</pre>
200(base 10) is 310(base 8) so in the fist '200' characters, 666 shows up 4 times (5 if you count 6666 as twice?) [[User:Xami|Xami]] ([[User talk:Xami|talk]]) 14:01, 18 November 2013 (UTC)

: The Wolfram result is what you get when you calculate pi*3/2 in decimal, round to 14 digits after the decimal point and then convert to octal. That is, 4.7123889803846910 converted to octal. Definitely, this won't give you 200 digits precision. --[[User:Ulm|ulm]] ([[User talk:Ulm|talk]]) 15:15, 18 November 2013 (UTC)
:: It lines up too perfectly to be a coincidence. It fits all the requirements: has 666 four times within 2008 digits, and although 0000, 222, 444, and 7777 appear, they only appear once as a run. You can't double count 7777 as two 777's because it is a single run. If WolframAlpha doesn't give the correct precision, it is likely that Randall made the same error. --[[User:RainbowDash|RainbowDash]] ([[User talk:RainbowDash|talk]]) 16:59, 18 November 2013 (UTC)

Being τ, tau, is already being expressed in terms of π, pi, it shows bias. (Though I think Pau would lead to some interesting spherical geometry equations. ~~Drifter {{unsigned ip|108.162.219.214}}

The bias is worse than that: From the perspective of π, the discussion is about multiples of π, so (3/2)π (that is 3π/2 = 3τ/4) is indeed the compromise between π and 2π. But from the perspective of τ, the discussion is about fractions of τ, so the compromise between τ and τ/2 is τ/(3/2) (that is 2τ/3 = 4π/3). Maybe we can call this ‘ti’ (or ‘tie’, pace 173.245.53.184 below). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:47, 18 November 2013 (UTC)

Actually, both compromises are wrong. (3/2)π is the arithmetic mean of π and τ, while τ/(3/2) is their harmonic mean. But for geometric ratios (which these are), the appropriate mean is generally the geometric mean (hence the name). You can see how even-handed this is: it's (√2)π = τ/(√2). —[[User:TobyBartels|TobyBartels]] ([[User talk:TobyBartels|talk]]) 20:50, 18 November 2013 (UTC)

---

I am in favour of just calling it ti(e). --[[Special:Contributions/173.245.53.184|173.245.53.184]] 17:52, 18 November 2013 (UTC)

---

There are real world uses to both Tau and Pi: Pi is the number that relates to what you get when you measure a circle (the distanced around divided by the distance across); and Tau is get when you draw a circle (the distance around divided by the distance from the center). It is the difference between a mic (aka "micrometer" http://en.wikipedia.org/wiki/Micrometer ) and a protractor. Tau might have some mathematical advantages in both 2D and 3D in that it has no integer attached to it to find either circumference (2D) or surface area (3D) which makes radians and solid angles simpler. However, that advantage is lost in other dimensions and for the area of a circle.

Pau, of course, has a 61% chance of going to the dribbling spheroid hall of fame. (ref: http://www.basketball-reference.com/players/g/gasolpa01.html ), to which neither Tau nor Pi can hold a candle.~~Remo ( [[Special:Contributions/199.27.128.183|199.27.128.183]] 19:19, 18 November 2013 (UTC) )

---

The differences between Wolfram and BC really bothered me since I have used both for precision calculation in the past. The long and short of the matter, having done most of the maths 'long hand', BC is correct, Wolfram is wrong, and sadly, Randall was also wrong. It seems as tho Wolfram is rounding pi*1.5 to around 15 decimals but leaving the 9 repeating before converting to Octal.

If you take the output of octal(pi * 1.5) and paste it back into the input like so:
<pre>
4.554574376314416445676661714336617116240444076666510533533077631151350452060436452476274022621206136310000177621674175071262255702044274154476005744176002676623042402346036604733130522524127534777_8
</pre>
Wolfram gives you back (converted to decimal):
<pre>
4.71238898038468999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
</pre>
If you give that same input to BC and ask it to convert to decimal you get:
<pre>
4.712388980384689999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999992894219160392567888
</pre>
If you do the math long hand out to 55 decimal places, pi * 1.5 equals:
<pre>
4.712388980384689857693965074919254326295754099062658731462416...
</pre>
Converting that by hand into octal is a bit of a pain, but if you do, at the 18th decimal place where BC and Wolfram differ you end up with the following:
<pre>
0.000000000000000183697019872102976583909889841150158731462416... is your remainder to be converted so far
0.000000000000000055511151231257827021181583404541015625 = 8 ^ -18
</pre>
Wolfram gives the 18th decimal as 5, BC as 3. I can't see 5 going into 18 5 times, but 3 times fits nicely.
--[[User:DarkJMKnight|DarkJMKnight]] ([[User talk:DarkJMKnight|talk]]) 20:04, 18 November 2013 (UTC)

Looks like Wolfram is simply using floating-point mathematics, presumably the IEEE "double precision". Interestingly, this is not the first time floating-point maths has been a problem; in [[287]], a similar problem caused an unintended trivial solution. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 04:41, 19 November 2013 (UTC)
* On second thoughts, there's no indication that he used Wolfram Alpha; as with [[287]], it simply could have been a Perl script (or Python or pretty much any programming language). [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 05:25, 19 November 2013 (UTC)

---

How can 200 be octal and then mean 310 decimal???
If 200 were octal, that would be 128 decimal, so we would end up writing 128 decimals.
Of course 310 octal is 200 decimal, but taking 2008 to mean 31010 is plain crazy, even if it's the only way to make it fit the "four times 666" constraint!
What am I missing here? [[Special:Contributions/173.245.53.149|173.245.53.149]] 21:27, 18 November 2013 (UTC)

This Mathematica code searches for the pattern 666 in the octal expansion of 1.5 pi:
<pre>digits = RealDigits[3*Pi/2, 8, 10000][[1]]; Select[Range[10000 - 2], Take[digits, {#, # + 2}] == {6, 6, 6} &]
{279, 326, 495, 496, 3430, 3728, 4153, 6040, 7031, 7195, 7647, 7732, 8353, 8435, 8436, 8575, 8768, 9008}</pre>
These positions start counting with the leading "4" as position 1. It does not occur in the first 200 digits, but occurs 18 times in the first 10,000 digits. Many other digit combinations occur more times in the first 10,000 digits, including "123" (23 times), "222" (21 times), and "555" (26 times). Note that "xkcd" converted to numbers (a=1, b=2, etc.) is 24, 11, 3, 4. The combination 241134 first occurs in 1.5 pi at digit number 250,745. [[User:Dcoetzee|Dcoetzee]] ([[User talk:Dcoetzee|talk]]) 06:44, 19 November 2013 (UTC)

Wow, this filled up fast. Is it time to remove the Incomplete tag yet? [[Special:Contributions/199.27.128.66|199.27.128.66]] 03:14, 19 November 2013 (UTC)

:Please do your adds at the bottom. Otherwise it looks like as the first discussion here and everybody will ignore your comment.
:My answer is: NO. We still have to figure out if Randall is wrong or just using an algorithm nobody does understand right now.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 21:10, 19 November 2013 (UTC)

---

Someone said there's no indication that Randall used Wolfram, and that double-precision IEEE numbers in mostly any language would cause the same error.
This is not true: IEEE double precision numbers (binary64) are stored internally in binary.
Converting them to octal would give at most 18 nonzero significant (octal) digits, and from that point on all additional digits would be zeros (remember that an octal digit is equivalent to three bits).
What Wolfram does is rounding to a decimal number, which is not round in octal.

I think the previous is an indication that Randall did indeed use Wolfram.
Added to that, he used Wolfram in several what-if's, and in one case he used it so heavily that his IP got temporarily banned from Wolfram.
This leaves little or no doubts in me that Wolfram is the source of Randall's mistake.

Also, I still would like to know why everybody is interpreting "200 digits" as "2008 digits" and pretending that's equal to "31010 digits" instead of "12810 digits".

And out of curiosity, what happened with [[287]] and floating point numbers?
The explainxkcd for 287 says nothing about floating point.

[[Special:Contributions/173.245.53.145|173.245.53.145]] 22:09, 19 November 2013 (UTC)
* With [[287]], there was only meant to be one solution, the other solution was unintended. It's mentioned in the discussion only, not in the body of the explanation, but there's a link to an interview where he indicates that it was indeed unintentional. [[User:Sabik|Sabik]] ([[User talk:Sabik|talk]]) 07:13, 20 November 2013 (UTC)

;What is the period of the wolfram answer?
What is the repeat period of the octal answer with the 666's, (the length of the repetend) i.e. the one that comes from Wolfram, that is converting 4.71238898038469 decimal to octal? And how many 666's are in the full repetend? Oooh - I like that new word - thanks to {{w|repeating decimal}}! [[User:Nealmcb|Nealmcb]] ([[User talk:Nealmcb|talk]]) 23:22, 19 November 2013 (UTC)

:Dunno, either Randall uses WolframAlpha whithout further checks, so he has to check his sources, or we all are just dumb.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 23:54, 19 November 2013 (UTC)

: The period is 4882812500. Yes, what I mean is that it repeats every 488281250010 digits. Not sure I want to count the number of 666's in there. Oh, and thanks for the answer about [[287]], I've seen it now. -- [[Special:Contributions/173.245.53.139|173.245.53.139]] 17:46, 20 November 2013 (UTC)

I hardly dare to ask now... ;)
*What is an octal expansion?
*This explanation cannot be complete before someone explains what this actually means, to someone who have never herd of octal expansion before (like me)
[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 15:33, 21 November 2013 (UTC)
:You are absolutely right, the incomplete tag is back. It seems only math geeks were working here but it should also be explained for people with less knowledge on math.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 22:02, 21 November 2013 (UTC)

:*The wikipedia page for {{w|Octal}} contains a complete explanation. I wrote a plainer one but mine is still very long, so instead of posting it here I uploaded it [http://www.jojonete.com/00/20131121_Octal/ there]. It's very crappily formatted and not thoroughly checked as I don't have time for more at the moment, but I might improve it some other day. Please note that the only reason for not posting it here is its length, and in particular it has nothing to do with copyright issues. I mean, everybody feel free to copy, rewrite, summarize, expand, correct, destroy or do whatever to that text with no attribution, just as if it had been posted here. --[[Special:Contributions/173.245.53.145|173.245.53.145]] 22:37, 21 November 2013 (UTC)

::The explain for non math people should be much more simple. Randall likes simple English, I like simple Math. Not everything is covered but more people will understand the essentials. While I like all that details many people don't. We still do need an simple Math explain here.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 23:42, 21 November 2013 (UTC)

::I know and I agree, that's why I kept my explanation out of this discussion. My summarizing skills are just not good enough. I used the time I didn't have to reformat my explanation, but that just means it's now a bit longer than it was. I hope someone else will write a much shorter and simple one, as I just seem to be unable to do so. --[[Special:Contributions/173.245.53.145|173.245.53.145]] 01:10, 22 November 2013 (UTC)

:::Thanks for a great explanation. I knew about this system but only for integers. However, still need a word on how to get pi in Octal. Until anyone does better a link could be posted for your explanation! [[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 19:54, 23 November 2013 (UTC)

::::I added the conversion part to the explanation, it's in the same link. Still way too long to post here. --[[Special:Contributions/173.245.53.117|173.245.53.117]] 03:29, 29 November 2013 (UTC)

Note that pau is Catalan for peace, which is a good solution for the pi/tau dispute. --[[Special:Contributions/173.245.53.150|173.245.53.150]] 00:10, 23 November 2013 (UTC)

:Has posted this as a trivia item. [[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 20:11, 23 November 2013 (UTC)

The trivia that states that e here represents Euler's Constant, and not Euler's Number, seems to be false, is it not? e+2 being ~4.71, not ~2.58. --[[Special:Contributions/108.162.237.11|108.162.237.11]] 17:39, 24 November 2013 (UTC)
:I have removed that sentence. It was simply wrong. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 19:35, 24 November 2013 (UTC)