explain xkcd - User contributions [en]

Talk:2622: Angular Diameter Turnaround

2022-05-22T10:13:15Z

162.158.34.207: /* The crap is spreading... */

== Congratulations, you won a brand new galaxy! ==

Your new galaxy will be delivered in only 3 billion years, to a drop-off point only 1 million light years from your home planet. With this cutting-edge protogalaxy, which will be mature upon delivery, you will find incredible features such as:
* supermassive black hole
* exotic space-faring lifeforms
* intriguing dense matter that does not emit radiation; you'll never have enough
* unique and enthralling galactic formations, each with ancient magical myths told in history by the space-faring lifeforms
* and the ability to grow brand new stars of your very own!
[[Special:Contributions/172.70.114.247|172.70.114.247]] 00:07, 21 May 2022 (UTC)

== Comments ==



Slightly creepy, NGL[[Special:Contributions/172.69.34.10|172.69.34.10]]
: Warning, horrible content: The universe was created by the severed bloody hands of google employees convincing phone manufacturers to ditch the previous phone backends and explode the google play store throughout reality in a mess of intergalactic gore. Our planet developed from an angrybirds download, nourished by the decaying corpse of the owner who played it all their life. [[Special:Contributions/172.70.110.209|172.70.110.209]] 20:37, 20 May 2022 (UTC)

So apparently this is a real thing, which I never knew [[wikipedia:Angular_diameter_distance#Turnover_Point]] [[Special:Contributions/108.162.221.81|108.162.221.81]] 20:46, 20 May 2022 (UTC)

Could be related to comic 1422, what with both containing expanding phones analogous to some cosmic structure. [[Special:Contributions/172.70.130.105|172.70.130.105]] 21:46, 20 May 2022 (UTC)
:[[1422]] has been crapped. [[Special:Contributions/172.70.126.221|172.70.126.221]] 21:50, 20 May 2022 (UTC)

So confusing…I thought that 13 billion years ago they had flip phones. [[User:JohnHawkinson|JohnHawkinson]] ([[User talk:JohnHawkinson|talk]]) 22:32, 20 May 2022 (UTC)

Before this explanation is marked “complete” it had better mention that “sinking into dilute blood” is a terrible (one could even say ignorant or stupid) description of red shift, completely missing the fundamental cause and completely distorting the effect. [[Special:Contributions/108.162.216.159|108.162.216.159]] 23:23, 20 May 2022 (UTC)
:Pretty sure that was just a description of its appearance? --[[Special:Contributions/172.70.210.125|172.70.210.125]] 10:18, 21 May 2022 (UTC)
::Randall implies this was an analogy among people who knew the physical underpinnings well. But I agree that it, and the concept of mobile phones, are neither pleasant nor appropriate at all for the outer reaches of our universe. [[Special:Contributions/172.70.230.63|172.70.230.63]] 15:28, 21 May 2022 (UTC)

I assumed the reference was that very old cell phones (1990s etc.) were enormous - think carphones; technology allowed them to shrink (giving, say, the Nokia 8850 I owned in 1999 and the original smallish iPhone), and then recent phones have (on average) grown again as the benefits of a larger screen area have been seen to outweigh the convenience of a smaller device. Also older phones tended to have batteries that lasted longer, mostly because neither the screen nor the processor were pulling much power. It's not just that the original iPhone was smaller than current ones (nor, for some of us, does the original iPhone count as an "early cellphone"). Am I alone in this interpretation? The description (at time of writing) didn't seem to cover that.[[Special:Contributions/162.158.159.121|162.158.159.121]] 10:15, 21 May 2022 (UTC)

The phone model shown doesn't look that much like a Samsung Galaxy. More like an iPhone. Oh, well. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 15:50, 21 May 2022 (UTC)

I hope we'll be able to procure a charger for our galaxy before it runs out. [[Special:Contributions/141.101.105.249|141.101.105.249]] 15:52, 21 May 2022 (UTC)

== Hooray! ==

Something good is happening!!!!!! [[Special:Contributions/172.70.126.215|172.70.126.215]] 21:22, 20 May 2022 (UTC)
: No. It just means you can't get a date tonight. Again. (I presume you're the "crap"per, right? Eager to fill your own worthless life by making ''everybody else'' actually feel useful... How ironic.) [[Special:Contributions/172.70.91.36|172.70.91.36]] 00:08, 21 May 2022 (UTC)
:: I thought it was just a visitor I worried I had badly depressed with my story of severed google hands, wanting to add positivity. [[Special:Contributions/162.158.79.112|162.158.79.112]] 00:21, 21 May 2022 (UTC)
: the "crap"er is a bot called "Explain xkcd server admin". -> https://www.explainxkcd.com/wiki/index.php/User:Explain_xkcd_server_admin/common.js [[User:Firestar233|Firestar233]] ([[User talk:Firestar233|talk]]) 00:11, 21 May 2022 (UTC)
:: Yes, same (style) as the umpteen previous times. No imagination and rather boring.
:: Now I'm limited in what I can do (still, been reverting pages left right and centre, to hold my bit up) but the "Hooray!" commenter (as, I suspect, the one who 'wished the crap would happen again' the other day, or words to that effect) seems to be very much like someone's idea of taunting us, thus proving that he (if you'll excuse that assumption) can't get laid and for some reason they haven't discovered the more solo method of getting their rocks off, so he's rubbing up against us and trying to generate the satisfying feeling of friction in his groin.
:: (You know when your dog has a favourite stuffed toy? Like that.)
:: Pretty boring, really, for us. But small things amuse small minds. And maybe that's the reason why. Also having small... 'feet'. Too shy to show his 'feet' to girls. Can't earn enough to get 'feet' enlargement surgery. No personality either. Pity. [[Special:Contributions/172.70.85.211|172.70.85.211]] 02:43, 21 May 2022 (UTC)

== F0N3Z!!! ==

WH3R3 C4N 1 G37 7H15 M4NY F0N3Z? (jk, 1 41r34dy h4v3 4b0u7 31gh7 0f 7h3m) [[Special:Contributions/172.70.178.115|172.70.178.115]] 02:59, 21 May 2022 (UTC)

== The crap is spreading... ==

[https://esolangs.org/wiki/Special:RecentChanges The Esolang wiki is being crapped.] We aren't the only ones... [[Special:Contributions/172.70.130.105|172.70.130.105]] 18:11, 21 May 2022 (UTC)
:I imagine there'll be a esolong ''called'' "crap" becore too long (if there isn't already) with which a decrappifier can be written. Knowing the people who used to be in that field, anyway. Sort of whitespace/brainf*ck-inspired thing, probably.
:(Too late now, but I hope it's not because we kept archive copies of our scripts around for others to pick up, independently of the original idiot.)
:But this goes both ways. If they come up with a better answer to the problem, maybe we can get it working here too. I leave it to those in the know to perhaps keep half an eye on that, though. [[Special:Contributions/162.158.34.207|162.158.34.207]] 10:13, 22 May 2022 (UTC)

== Arab Soyjak and other site vandalism ==

[[Special:Contributions/162.158.107.124|162.158.107.124]] is repeatedly changing the comic title to "Arab Soyjak" and the image to a picture of Osama bin Laden, and being awfully rude in the edit summaries; also has a history of vandalism along with various associated IP addresses - however also having made actual contributions to the wiki, etc etc, I haven't checked other IP addresses that are associated; [[416: Zealous Autoconfig]] is one of the pages that are currently vandalised </ramble> [[User:Bubblegum|bubblegum]]-[[User_talk:Bubblegum|talk]]|[[Special:Contributions/Bubblegum|contribs]] 02:56, 22 May 2022 (UTC)

1987: Python Environment

2022-05-20T23:18:58Z

162.158.34.207: Undo revision 271120 by Explain xkcd server admin (talk)

{{comic
| number = 1987
| date = April 30, 2018
| title = Python Environment
| image = python_environment.png
| titletext = The Python environmental protection agency wants to seal it in a cement chamber, with pictorial messages to future civilizations warning them about the danger of using sudo to install random Python packages.
}}

==Explanation==

A development environment is the collection of tools used to create a computer program. It generally includes an {{w|Interpreter_(programming)|interpreter}}, a {{w|package manager}}, and various {{w|Library_(computing)|libraries}} that the project needs. Computer programs often depend on a specific version of these tools, such as a program that only runs on Python 2.7. A badly configured build environment can lead to mysterious errors as the program looks for libraries or features that aren't there, making it hard to develop stable and portable software.

{{w|Python_(programming_language)|Python}} is a {{w|computer}} {{w|programming language}} which has been around for quite a while, especially on {{w|Linux}} platforms. [[Randall]] has shown his fascination with Python [[353: Python|before]]. He has likely used it on his computer for quite a few years, from the early years when it wasn't so easy to install, through newer versions where there is a more defined way to install it. Because standards change over time (in particular, although the newest version of Python is Python 3.x, many people prefer Python 2.x, and it's still widely used for backward-compatibility), and he didn't completely uninstall old versions before installing new versions (likely to not break what was already working), he's ended up with a mess where different pieces and versions of Python and its related components litter his {{w|hard drive}}'s {{w|directory structure}}.

{{w|Superfund}} is a US federal government program created for cleaning up contaminated land. The comic is saying that his computer's Python environment is so messed up that it's comparable to a real-world environmental disaster.

The title text may refer to the philosophical debate surrounding the construction of warning features around the [[wikipedia:Waste_Isolation_Pilot_Plant#Warning_messages_for_future_humans|WIPP]] site in New Mexico, and other nuclear waste disposal sites. In particular, it may refer to [https://web.archive.org/web/20090320054657/http://www.wipp.energy.gov/picsprog/articles/wipp%20exhibit%20message%20to%2012,000%20a_d.htm this article]. These would have to last and be understandable for tens of thousands of years, longer than any known human-made structure or language to date. It also refers to the use of "sudo", a Posix command utility that allows a user to operate with heightened permissions. Using "sudo" to install a Python package may make the package available to the entire system, or, based on the settings of Virtualenv/Anaconda, it may end up installing the package in a user's home directory. This would make it so that the user could not update, edit, or remove the packages.

;$PATH
:$PATH refers to the {{w|PATH (variable)|PATH}} environment variable, which determines where to search for executable files. In this case, it indicates that the pip, Homebrew Python (2.7), and macOS's pre-installed Python are accessible on path, with ~/newenv/ and a mysterious ???? as part of PATH.
;pip
:{{w|pip (package manager)|pip}} is the Python {{w|package management system}}, and is used to install and manage python packages. As it is written in Python, it requires Python to run. It leads to easy_install, Homebrew Python (2.7), "(misc folders owned by root)", and ????.
;Homebrew Python (2.7)
:{{w|Homebrew (package management software)|Homebrew}} is a third-party macOS package manager. Homebrew Python (2.7) is the Python 2 version installed through Homebrew. This leads to Python.org binary (2.6) and /usr/local/Cellar.
;OS Python
:Apple bundles an (out of date) version of Python with macOS. This only leads to ????.
;????
:With so many versions of Python installed and used in the system, it becomes very hard to track which Python program uses which version and environment. The system becomes unpredictable and its workings and faults mysterious. All parts of the graph that lead to this point, lead to confusion.
;easy_install
:easy_install, much like pip, is a cpan-like tool to download and install Python packages. As of the creation of the comic, many people discourage its use. (e.g., [https://stackoverflow.com/questions/3220404/why-use-pip-over-easy-install this question on stack exchange.])
;Anaconda Python
:{{w|Anaconda (Python distribution)|Anaconda}} is a Python distribution for data science and machine learning-related applications.
;Homebrew Python (3.6)
:As of the creation of the comic, Python 3.6 is the current stable version of Python. It can be installed together with Python 2.7 on the same computer. Care must be taken to use an appropriate version for every Python program, however. Homebrew is a "macos" package management utility. Presumably, Randal installed Python 3.6 with Homebrew (as opposed to downloading and compiling the language himself).
;Python.org binary (2.6)
:[http://python.org Python.org] is the home site of the {{w|Python_(programming_language)|Python language}} and provides its reference implementation. Among other stuff, there are downloadable installers that create ready-to-use Python environments for you (on Windows and macOS only). It makes little sense, however, to use it on a computer where Homebrew, Anaconda, and a locally compiled version are already present, since the Python.org version is the baseline one, doesn't give you any benefits, and can't be optimized for your needs. Having an obsolete 2.6 version, when the typically used 2.7 is already on the computer, also doesn't help. Some justified uses do exist (tests, programs that depend on this particular version), but in the end, an extra version of Python just adds to the overall confusion.
;(Misc folders owned by root)
:This suggests that over years [[Randall]] dropped various versions of {{w|Python_(programming_language)|Python}} environments everywhere around his computer, probably by hand without proper installers, and used root privileges to do so. The exact locations either are highly nonstandard, so it makes no sense to show them to us, or have simply been forgotten. Now it's hard to even tell where exactly those Pythons lay, what in the system depends on them, and if it's safe to remove them or not (because if installed by the root, they can integrate into unexpected places in the system; having them can break something, and removing them can break something).
;<code>/usr/local/Cellar</code>
:The default (normal) location of the {{w|Homebrew (package management software)|Homebrew}} Cellar, the directory where Homebrew actually stores the files of the installed packages. It's a storage-only location, the files, including Python, will be symlinked from other, more convenient places in the files tree, and should not be used through /usr/local/Cellar path directly. It seems that Randall broke this safety rule in the past, so some stuff of his accesses Python directly in the Cellar. Such setup can break if Homebrew performs automatic maintenance in the Cellar (like removing unneeded versions of the packages). The name cellar is likely a reference to the practice of storing wines and other alcohol in cellars, intended as a pun of homebrew.
;<code>/usr/local/opt</code>
:A folder that is usually created by Homebrew.
;/(A bunch of paths with "Frameworks" in them somewhere)/
:Python on macOS is often distributed as a framework and placed in a "Frameworks" folder. For example, the system-included Python distribution in macOS resides in /System/Library/Frameworks, and many package managers will also install the framework in a folder with this name.
;$PYTHONPATH
:The environment variable PYTHONPATH specifies the search path for Python modules to the Python interpreter. Having it refer to locations controlled by 3 different package managers, each of which is managing software for different versions of Python, as shown, is likely to lead to incompatible software being loaded together.
;Another pip??
:Pip is a {{w|Recursive acronym}} for "Pip Installs Packages." There should only be one installation of pip (or other package management system) managing any given working environment. Often, additional "pip" executables are installed based on the Anaconda settings for different virtual envs. This often leads to internal contradictions in the software. Randall is confused as to how this other one relates to the rest of the development environments.
;~/python/
:Might be another virtualenv, or, given the absurdity of the rest of the comic, even a manually compiled python installation (many online guides instruct users to extract sources into the home (~) directory).
;~/newenv/
:Probably a virtualenv. Virtualenvs are mechanisms for having Python environments that don't conflict with the system Python. They include the Python interpreter, independent library paths, and usually a copy of pip. The user typically installs packages using the virtualenv's pip such that they can only be accessed by the virtualenv's Python instances, while more common packages are still referenced via the system Python paths.
;/usr/local/lib/python3.6
:The default place under a Unix-like OS for the Python 3.6 standard libraries for a locally compiled Python 3.6 interpreter.
;/usr/local/lib/python2.7
:The default place under a Unix-like OS for the Python 2.7 standard libraries for a locally compiled Python 2.7 interpreter.

==Transcript==
:[A single frame depicting a flowchart is shown. Many chaotic arrows are arranged between the items which are:]
:$PYTHONPATH
:EASY_INSTALL
:ANACONDA PYTHON
:HOMEBREW PYTHON (3.6)
:ANOTHER PIP??
:HOMEBREW PYTHON (2.7)
:PYTHON.ORG BINARY (2.6)
:PIP
:EASY_INSTALL
:$PATH
:(MISC FOLDERS OWNED BY ROOT)
:????

:[The endpoints are:]
:/usr/local/Cellar
:/usr/local/opt
:/(A BUNCH OF PATHS WITH "FRAMEWORKS" IN THEM SOMEWHERE)/
:~/python/
:~/newenv/
:/usr/local/lib/python3.6
:/usr/local/lib/python2.7

:[Caption below the panel:]
:My Python environment has become so degraded that my laptop has been declared a superfund site.

== Trivia ==

* A similar comic is {{xkcd|1654}} which is the same but for multiple languages.

{{comic discussion}}

[[Category:Computers]]
[[Category:Programming]]
[[Category:Flowcharts]]