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October 4

Toon Boom Animation's removed filmography sections

Hi. The Films, TV Series, Music Videos and Video Games sections on Toon Boom Animation were removed in August for being unsourced. Can anyone here please find sources for the titles? Thanks! 178.22.170.123 (talk) 04:57, 4 October 2017 (UTC)

Note similar requests here and here. 青い(Aoi) (talk) 07:47, 4 October 2017 (UTC)

Note also the history of that page. (((The Quixotic Potato))) (talk) 10:06, 4 October 2017 (UTC)

October 6

Creating a vector image out of a white transparent png file

I've watched every "png to vector" tutorial video and read a million message board posts but still can't figure this out and I need it done for work: I have a png file that is a white graphic with a transparent background, and I need to make it be a vector file. In Illustrator when I trace it, it just makes it be an entirely white square. When I invert the colors and trace it as a black image, it seems to work, but as soon as I reverse the colors back to the original, the white portion of the graphic disappears - so frustrating! Is this even possible? ReferenceDeskEnthusiast (talk) 14:52, 6 October 2017 (UTC)

I used Inkscape's Path > Trace Bitmap feature to do this. This archive has the input png and the output svg, and a screenshot of the settings of the trace-bitmap dialog I used. -- Finlay McWalter··–·Talk 15:12, 6 October 2017 (UTC)

Got this going now, but I'm at Step 1 of the "2. Multiple Scans" section and when I hit the OK button, nothing happens. The Trace Bitmap panel is there and the OK button blinks as I click it and nothing occurs, it's not traced and the panel doesn't go away. I had to call tech support to get admin access to install this program to try this. Any idea how to do this in Illustrator? ReferenceDeskEnthusiast (talk) 16:01, 6 October 2017 (UTC)

http://www.instructables.com/id/Turning-a-pixel-image-into-a-vector-image-using-Ad/ (((The Quixotic Potato))) (talk) 16:05, 6 October 2017 (UTC)

http://www.graphics.com/article-old/converting-rasters-vectors-using-live-trace-illustrator Google "raster to vector illustrator" for more (((The Quixotic Potato))) (talk) 16:08, 6 October 2017 (UTC)

Yeah that's exactly what I've done, but using any of these steps inexplicably removes the white portion of the graphic and leaves in the colored sections. Can't find a single video or discussion that addresses this. This is what's so frustrating, I can easily get it as a vector in the inverted colors. ReferenceDeskEnthusiast (talk) 16:14, 6 October 2017 (UTC)

Solved! Finally got it. The trick was to invert it, trace it, save it as an .svg, close the window, open the .svg, and invert the svg file back to the original colors. ReferenceDeskEnthusiast (talk) 16:49, 6 October 2017 (UTC)

High Quality Image Library

Is there anywhere that I can download, freely, a large collection of images that are uncompressed - preferable of varied subjects: landscapes, people, etc.? Ultimately, the images will end up as bitmaps to be processed; I've been pulling images from Google image searches, and the like, but it is hard to tell exactly how much noise my uses for them are introducing versus how much noise is due to compression artifacts that are not readily visible in the original. In the event there are no free solutions, I'd be open to any source that had a reasonable price (less than $100, though that's more money than I'd like to spend). While on the subject, a related question: which image has more noise: a very large bitmap turned to a jpeg, then downsized or a very large bitmap, downsized, then compressed?Phoenixia1177 (talk) 17:06, 6 October 2017 (UTC)

Try searching for "RAW format images", then process them as you like. Under Google + Images, I picked "More Tools + Sizes + Larger than ... 4 MP". Note that you'll find more images of landscapes and buildings under this search than close-ups of people, as people tend not to look good when you can see that level of detail (pores, etc.). StuRat (talk) 17:24, 6 October 2017 (UTC)

NASA is good about publishing uncompressed, high resolution TIFF files of most of their images.

It's not all space photos either. A lot of it seem to be pictures taken of engineers building things, PR photos, launch-pad photos, and various other random photos of NASA personel, fascilities, and equipment.

https://photojournal.jpl.nasa.gov/gallery/snt

ApLundell (talk) 17:50, 6 October 2017 (UTC)

But I wouldn't assume these images have never been lossy compressed. Are we certain that NASA is careful enough with their workflows for all those other images to ensure they were never lossy compressed (or if they were, this is clearly marked)? AFAIK, even some cheaper DSLRs only provide a lossy compression option by default [1]. Of course, noise can come from a variety of sources besides compression artifacts, and it can get quite complicated what you actually mean by a non-lossy compressed 'raw' image for the sensor, so I'm not sure there is a reason for the OP to concentrate on noise from lossly compression. (I suspect Nimur will have a lot to say about this, if they get to it.) Nil Einne (talk) 12:12, 8 October 2017 (UTC)

For the sake of brevity, let me summarize: users of any scientific image must be very careful to understand how the image was created.

Many people conflate two totally unrelated concepts: (1) data may be uncompressed (or it may use lossless compression); (2) data may be unprocessed - it may be in a form that directly corresponds to digitized sensor data. These concepts are entirely orthogonal (independent of each other).

NASA scientific imagery is usually published through one of the main databases - for example, Planetary Data System (PDS). PDS data is annotated with metadata and links to technical publications that explain how the imagery or raw data you see has been processed. For example, this summer I spent a few weeks training new scientists in the theory and practice of interpreting LRO camera imagery. You can get JPEG files, and you can get TIFF files; but if you want to do photogrammetry or radiometry, you need to do a lot of extra homework to learn about the camera instrument, and the software that runs before you get a data-file. "Raw data" is a term that should be avoided: instead, professional scientists refer to the exact data product that they are using, so that it is clear to others exactly what type of data they mean. For example, there are "engineering data records," "scientific data records," and so forth.

As one clear example: LROC camera data may be provided in a TIFF file, but it has already been companded - the dynamic range has been reduced, to fit into an eight-bit numeral. Even if you get an "uncompressed" TIFF file, the spacecraft itself has compressed that pixel from the original 12 bits (usually). The only way to correctly interpret the image is to pull up the orbital record (the Calibrated Data Record, for example) and invert the companding equation. This is a complicated process, unique to this instrument.

So - beware of "raw" data - the only real raw data is an analog signal! The minute that signal gets preprocessed by hardware or software, you (the consumer) have to do a lot of homework to understand every single step in the data acquisition pipeline, from sensor electronics, to acquisition software, to storage-and-transmission signal conditioning, to scientific post-processing, to archival file-formatting, to data compression for long-term storage. The very same caveats apply to "conventional" photographic data - only, it's not so cleanly documented!

Nimur (talk) 20:15, 9 October 2017 (UTC)

How to find "effective resolution" of pics ?

Is there a way to determine the original resolution, say of a pic that has been upscaled but has no history stored with it ? I can get a general idea by how blurry the pic is, but there must be a more scientific approach. StuRat (talk) 22:46, 9 October 2017 (UTC)

The "obvious method" is to observe the energy spectrum produced by the spatial frequency transform, and observe whether there is a distinct fall-off at a maximum spatial frequency. That spatial frequency value would correspond, conceptually, to the "original" pixel size.

This of course assumes that the upscaling algorithm is "dumb," in that it blurs during upscaling - but this is not representative of any modern method. Modern methods preserve gradient directions, improve and sharpen, mixed with matched noise-fill to yield high-frequency content, ...

A Tour of Modern Image Processing... (IEEE Spectrum, 2013), provides, well, a tour of all the horrible new math you need to learn if you plan to make quantitative sense out of modern digital images.

StuRat, you might enjoy reading pixel-art scaling algorithms - after viewing a lot of those sample images, you'll get a good conceptual understanding for why a purely mathematical treatment is almost impossible - modern upsampling algorithms are nonlinear filters; they yield an "ill-posed inversion problem;" this is math-ese for "you can't get a provably-correct answer."

Nimur (talk) 23:07, 9 October 2017 (UTC)

I was thinking more of a solution like this:

1) Recognize an object in the pic. For example, recognize a rose.

2) Compare with various stored images of that object, at various resolutions, to determine which is most similar in effective resolution. StuRat (talk) 23:18, 9 October 2017 (UTC)

Another possible method is to downscale it until a loss of quality becomes apparent. The last point before that became apparent is the effective resolution. StuRat (talk) 23:20, 9 October 2017 (UTC)

That's sort of like a keypoint detection method or a image saliency approach - it's an active area of research, but it's more along the lines of a machine-vision method, rather than a method of conventional image processing. Nimur (talk) 23:33, 9 October 2017 (UTC)

October 7

Windows 10 Shred

If I place a cursor on a file directory (folder) and right click on the mouse I expect to see "disconnect" if that is an external hard drive or a DVD drive. I don't see it. What I see is "Shred."

What is the Shred in this context? --AboutFace 22 (talk) 00:12, 7 October 2017 (UTC)

Sounds like a more thorough version of deletion, like a paper shredder, so I would only test it on a folder you don't care about. StuRat (talk) 00:43, 7 October 2017 (UTC)

Most likely, it is a Context Menu Extension provided by third-party (non-Microsoft) software.

"File shredding" is a fancy name for deleting a file, and then making sure it stays really deleted and can't be brought back.

A lot of 3rd-party software exists to provide "secure file deletion" features. A lot of that software is based on fairly unsound, unscientific ideas about the file system and its physical manifestation in real hardware. A non-trivial percentage of "secure file deletion" software is trojan horse-style malware. Most of it is just benign, useless clutter that promotes certain pervasive old-wives-tales about information security.

Evidently, what-ever software is providing "file shredding" on your computer is implemented so poorly that it thinks it can "shred" a DVD - which is, for the most part, impossible - DVDs are a read-only file system - hence, DVD-"ROM" (read-only memory). Windows won't let you write to a normal DVD, let alone delete files from it.

At this time, there is no sound reason for a user of a mainstream system like Windows to believe that any software does a better job at "delete" than the built-in feature provided by their operating-system.

Nimur (talk) 00:47, 7 October 2017 (UTC)

There are definitely programs which do this. Windows deletes the filesystem's information on a file but not the actual data which makes up the file, meaning it can be recovered. Programs like PeaZip can zero-delete a file (overwrite the file with a string of zeroes, so that no software can recover it from the hard drive) or secure-delete (repeatedly overwrite it with random digits such that even specialist forensic hardware will be unable to read the original data). There is a wiki article about the security consequences of nominal file deletion here.Speedstyle101 (talk) 11:29, 7 October 2017 (UTC)

Citation needed? Why do you believe Windows does not delete the "actual data" of a file? Why do you believe that another program does delete the "actual data"? Why do you believe that overwriting data with "zero" is identical to deleting the data? These are strong statements with significant technical consequences. Variations on this theme are frequently repeated without any factual basis.

Here's a conference paper on data remnance.

Here's another tech note on security considerations pertaining to User Experience Virtualization. Files can be replicated; redundantly committed to multiple storage media; transmitted over a network to a backing service; and so on. There is no way that application software can possibly be aware of all possible copies of a block of data - so even if we accepted the dubious claim that file data needs be "zeroed out" one or more times, the application can't know where all the copies are! It can't write zeros over data copies that it doesn't know about!

The take-away message is simple: only your operating system knows how data is permanently committed to the file system and its backing storage media. If you cannot trust your operating system, then you can not be assured that your data is securely "gone."

In practice, you should worry less about deleting, and more about encrypting. If your data is securely encrypted, it does not even need to be deleted. If someone gets a copy of the file, but they do not have the means to decrypt the contents, then the data is "gone" even if it isn't zeroed. Securely encrypted data is indistinguishable from an "empty" file - and on a modern computer system, neither is filled with "all zero"!

Nimur (talk) 13:08, 7 October 2017 (UTC)

File systems almost universally don't touch the file data when deleting a file; they just nuke the file system metadata that marks the file. (In Unix-land, this means the file inode(s) is/are unlinked. The libc function to do this is even called unlink(). And because of how Unix works, the file isn't even freed if any processes still have it opened.) So I think it's accurate to say that typically the "actual data" is not erased. Your other points are relevant, especially with the increasing use of cloud storage (like Microsoft's own OneDrive) which can copy users' data automatically. In a nutshell: if you care at all about other people having access to your data, encrypt it, and ensure it's encrypted if copied to any other storage medium, like an online backup provider. --47.138.160.139 (talk) 20:08, 8 October 2017 (UTC)

So, it looks like there is no "eject" anymore, only "shred." You know Windows software is getting more and more difficult to use. --AboutFace 22 (talk) 16:13, 7 October 2017 (UTC)

Well, I think I can enlighten you guys a little. I figured out that "Shred" appears to be McAfee malware. I use Spybot Search and Destroy, paid version, for antivirus and computer protection in general, however McAfee installed their exec without my knowledge and permission once I purchased this HP Pavilion Windows 10 computer. Once in a while I see a popup saying that my subscription has expired. I ignore that. Now I just found an empty folder and decided to shred it. Once I clicked "Shred" in the right click menu, A big McAfee popup came up offering me parameters for the shredding and a hint that I should purchase the full McAfee for this shred to work. I closed the popups and deleted the folder. It worked. --AboutFace 22 (talk) 17:26, 7 October 2017 (UTC)

Isn't that what everyone told you? (Well we had no idea what software it was coming from, but it was fairly obvioust it wasn't a prt of Windows itself.) Nil Einne (talk) 11:53, 8 October 2017 (UTC)

McAfee was almost certainly pre-installed on your computer by the manufacturer. They pay manufacturers to install their software, hoping to get customers who buy the computers to purchase subscriptions. --47.138.160.139 (talk) 20:08, 8 October 2017 (UTC)

Some McAfee products are sneakily pushed as "optional offers" (with the option to install them selected by default) when you download Adobe Flash, so it may have sneaked onto the computer that way. AndrewWTaylor (talk) 20:31, 8 October 2017 (UTC)

Java: serialize one version of a class, deserialize another

Is it possible, within a single Java process, to instantiate one version of a class, serialize the object to a ByteArrayOutputStream, and ensure that it deserializes as an instance of a different version of the class when read back in from a ByteArrayInputStream wrapping the output stream's array? What examples are available of how to do so? (What I want this for is unit testing; for instance, to test a readObjectNoData() method, I'll need a class to gain a new parent class between serialization and deserialization.) NeonMerlin 05:29, 7 October 2017 (UTC)

Wikipedia is great and all, but go to Stack Overflow for this sort of thing. Speedstyle101 (talk) 11:31, 7 October 2017 (UTC)

DNS resolution of 'subdomains'

Example, a Minecraft server called "grimworld.serv.nu" cannot be resolved; I can't ping it, and DNS lookup shows "DNS Error - No A records exist for grimworld.serv.nu".

So how come I can connect to it from within the game, which connects to port 25565? What IP address is it connecting to, and how is the traffic being passed?

As I understand it, there are many servers hosted as SOMETHING.serv.nu. So do they somehow redirect traffic to the correct one, depending on the subdomain? Am I actually connecting to just serv.nu, and being passed through to the right server (presumably on different ports)? — Preceding unsigned comment added by 86.20.193.222 (talk) 17:46, 7 October 2017 (UTC)

How does Minecraft talk to the server? Have you packet-sniffed this?

My suspicion is that Minecraft doesn't use "grimworld.serv.nu" as a DNS subdomain, it only uses serv.nu (which DNS understands and can resolve). Internally to the Minecraft application protocol, it passes "grimworld" as a parameter within that.

Your port is probably allocated dynamically on the basis of a session, not tied long-term to a particular subdomain. Two clients might connect to that subdomain and be given different ports for it. Andy Dingley (talk) 09:38, 9 October 2017 (UTC)

Hi Andy, thanks for responding.

Minecraft is only communicating with it on TCP, port 25565. I know that, because it has to be permitted through a firewall, and from all documentation I've seen about it.

You can run your own server, and it defaults to that port number - or you can specify it in a 'server.properties' file. Your friends can connect to you, using your external IP address - or, of course, you can pay for domain registration services.

Most servers (as far as I know) just resolve their IP address in the normal way, to a normal address which reponds to "ping", gives DNS info, and so on; for example, minecove.org, play.lokamc.com, mc.drugrun.net - those are random examples out of many thousands.

There is a small utility that can check if the server is online by sending a specific RCON query to that same port; an example of it in operation is here (and source available)

https://dinnerbone.com/minecraft/tools/status/ — Preceding unsigned comment added by 86.20.193.222 (talk) 10:10, 9 October 2017 (UTC)

Well that tool doesn't seem to show grimworld.serv.nu as working. Barring Andy Dingley being write or an insane TTL (did you try to ping and connect to the server on the same computer?), an obvious question, are you sure you're connecting to the hostname grimworld.serv.nu in Minecraft? If it's a saved server, are you making sure you're looking at the actual hostname that it's using to connect? If you're looking at the server description, I could say my server hostname is i.am.notch in the description, but it wouldn't make it so (not least because I suspect there's no notch GTLD). The server having a different hostname from grimworld.serv.nu stored inside Minecraft perhaps isn't that likely (unless Minecraft has some sort of update mechanism), but it having an IP stored rather than the hostname seems easily possible. It's also possible, although I find this unlikely, that Minecraft stores both a hostname and IP for the server, and if the hostname doesn't work tries the port. Assuming that serv.nu or Minecraft doesn't require the correct hostname for the Minecraft server to know which particular game service you're trying to connect to (like many web servers do need), having the IP would work. Nil Einne (talk) 16:20, 10 October 2017 (UTC)

Yes, I am using the same computer - the one I am writing on now. I am not using a stored server name. I can, now, in Minecraft, "Direct Connect" to "grimworld.serv.nu" and it works fine. Yet I cannot ping it, I can't even resolve the IP addresss to anything.

Meaning date command in Linux

Why is it, for example:

date +"%T"

and not, just

date -T

Why bother to type a + or %? What does these mean syntactically?--Hofhof (talk) 19:15, 7 October 2017 (UTC)

Try "man date" or better still, "info date". "+" means, use the current time/date. The string is a format with "%T", "%A", "%y", etc., place holders for various bits of date/time information. You can do stuff like

  date +"The calendar says it's %A and the clock says it's %T"

that you wouldn't be able to do with ordinary command line options. --Wrongfilter (talk) 19:35, 7 October 2017 (UTC)

To elaborate, that's the syntax the creators of the date command decided to use, so, as demonstrated, you can do more complex stuff. The syntax is almost certainly patterned after C's printf function. People not familiar with the Unix world sometimes don't realize this, but the -X convention for command-line arguments is just that, a convention that software authors voluntarily adhere to. It isn't enforced by the kernel or any other part of the operating system. The arguments are just passed as strings by exec to the program, and it's up to the program to interpret them however it wants. --47.138.160.139 (talk) 20:21, 8 October 2017 (UTC)

October 9

Runtime Limit

What is the best way to set a runtime limit on a process in Linux? If the cronjob foobar.sh doesn't finish within an hour I want it to be killed. Dragons flight (talk) 17:54, 9 October 2017 (UTC)

One way is to use the timeout command; for example

timeout 3600 foobar.sh

will send SIGTERM to the foobar.sh process after it has been running for one hour. But you need to make sure that foobar.sh exits cleanly when it receives SIGTERM. CodeTalker (talk) 19:55, 9 October 2017 (UTC)

Note that this limits the amount of elapsed time, not CPU time. StuRat (talk) 00:09, 10 October 2017 (UTC)

Thanks. Dragons flight (talk) 04:13, 10 October 2017 (UTC)

To limit CPU time, use ulimit, which is a bash built-in; for example

ulimit -t 3600; foobar.sh

--69.159.60.147 (talk) 02:10, 10 October 2017 (UTC)

October 10

Any JavaScript (history API) expert in the audience?

I run the following code in facebook.com. The code hides all "People You May Know" (PMYK) boxes which appear in numerous areas of the site.

My problem:

The code works, but after executing it (either with Greasemonkey/Tampermonkey) I cannot access my faceook conversations page.

When navigating to the conversations page by clicking the messages icon, then, "See all in messenger", my conversations page appears as a blank page.

My code:

let utilityFunc = ()=>{
    let run = (run)=>{
            setInterval( ()=>{

                // PMYK:
                    document.querySelectorAll(' #timeline_tab_content, #pagelet_pymk_timeline ').forEach( (e)=>{
                        e.style.visibility = "hidden";
                    });
            }, 250);
    };

    let pS = window.history.pushState;
    let rS = window.history.replaceState;

    window.history.pushState = (a, b, url)=>{
        run(url);
        pS.apply(this, arguments);
    };

    window.history.replaceState = (a, b, url)=>{
        run(url);
        rS.apply(this, arguments);
    };

};

utilityFunc();

My question

Why would this code cause that

You might have more luck at www.stackoverflow.com with this type of question. That said, you could try changing "hidden" to another attribute that is different, but still visible: that would tell you if your code is directly modifying the conversations part of the page (it doesn't look like it should, but I'm not too familiar with Facebook's API). OldTimeNESter (talk) 11:11, 11 October 2017 (UTC)

October 11

Password manager for FreeBSD?

Currently I am running an 11.1 version of FreeBSD. Since few years I have been using Pass (software) as my password manager, and BlackBerry's default "password keeper" on my mobiles.

The pass is a command based software. I was wondering, if there are any other graphical manager? Minimalist graphics would work too. If the software is cross-platform, it would be better. Thanks a lot in advance. —usernamekiran(talk) 21:48, 10 October 2017 (UTC)

I would strongly suggest Password Safe. (Home page) --Guy Macon (talk) 01:43, 11 October 2017 (UTC)

Thanks Mr. Macon. (Calling someone "guy" feels odd even if it is their name or last name.) Also, your wording assured me about it. Without it, I wouldnt have considered much about looking into "Password Safe". I looked it up on official freeBSD forum, and on some other sites. It looks really good for my usecase. I have been using freeBSD since around 2007. Even though I am very good with them, I never relied on "Pass", "password keeper" or any other manager till now. I used to do everything manually, and never noted anything anywhere (neither soft nor hard-copy). I will install it after Oct 18th. I might let you know about my experince on your talkpage (in case this thread gets archived by then). See you around. :)
—usernamekiran(talk) 17:13, 11 October 2017 (UTC)

Glad to hear it. I am looking forward to hearing how it works out for you.

I personally am old school: I have an ASCII text file with all of my usernames, passwords etc., which I keep encrypted using VeraCrypt using AES-Twofish-Serpent encryption and RIPEMD-160 hashing.

My VeraCrypt passphrase is 12 words/64+ characters which exists only in my brain -- I have never written it down or spoken it aloud. I store the encrypted file in multiple locations, but I only look at them using a dedicated laptop running Tails with no Internet connection. (I have been thinking about switching to OpenBSD for this -- any comments on that are welcome).

The individual website passwords all look like this:

• Username: WQn6tisJ51s2jBtl (when possible. Wikipedia, for example, doesn't allow seperate login and displayed usernames)
• Password: PGZGH%RhT7kZu3EG!ZFfRgwnfXGpXvg6
• What is your mother's maiden name: Ickaysaf Biocus Eipgha Acwefdo

And each website gets a unique, hard to guess email address. (Tuffmail makes this easy to do).

Mandatory XKCD: https://xkcd.com/538/

BTW, "Guy Macon" is the name on my birth certificate. Then there was the time I visited Mexico with my friend, Don... --Guy Macon (talk) 17:57, 11 October 2017 (UTC)

The even more likely method to crack the password is to read it off the sticky note the owner leaves attached to the laptop, because the long, constantly changed password with a mixture of upper- and lowercase characters, numbers, and symbols makes it impossible to recall.

As for your name, you sound like a superhero in Macon, Georgia. :-) StuRat (talk) 21:19, 11 October 2017 (UTC)

51% attacks on BOINC?

Are volunteer computing projects such as BOINC susceptible to something analogous to the "51% attack" some cryptocurrency experts worry about, in cases where there is suspected to be a well-funded interest in distorting the output of the computations (e.g. climate-change forecasting)? If I understand correctly, BOINC will accept an output that has been produced by 2 apparently-independent nodes. It's not clear to me what happens when those 2 nodes disagree; but even if the response is always to fail over to a perfectly trustworthy computer, then anyone who controls 50% of the computing power and IP addresses can control 25% of the output, and with 71% one can control 50%. (Which is better than cryptocurrency blockchains, where -- as I understand -- controlling 51% of the hashing power means controlling much more than 51% of the blockchain's contents, but still worrisome.) NeonMerlin 03:28, 11 October 2017 (UTC)

No. Bitcoin is vulnerable because it has no central authority. With BOINC, whoever controls the server can spot check the output of the clients, comparing the answer they gave to the answer his own computer gives. --Guy Macon (talk) 04:50, 11 October 2017 (UTC)

Right, but how many BOINC beneficiaries are savvy enough to do that? And how reliably can they do so, given how much tighter their computational constraints are than the BOINC network (assuming the difference was enough that they had a good reason to turn to BOINC in the first place)? NeonMerlin 05:14, 11 October 2017 (UTC)

We probably need to know what task is being computed to discuss further. There are quite a few problems where checking a solution is trivial compared to finding it. For instance, if the task is finding a hash collision (à la BitCoin), it is trivially easy to check even if it takes firepower to find. I have no ref right now, but quite a few protein folding problems boil down to "find the lowest-energy configuration" (in a very large configuration space); it is easy to check that a given configuration has the claimed energy, so if at any point in the calculations you find node B has found a lower-energy configuration than node A by using the same algorithm, you can kick out node A and all the results it gave you previously because something fishy is going on; presumably, if you rotate the association of pairs of nodes, eventually the good nodes will kick out the evil ones. Tigraan^{Click here to contact me} 09:21, 11 October 2017 (UTC)

Also if there are disagreements, then the job is farmed out to more nodes to check, until there is agreement in the result. Graeme Bartlett (talk) 09:10, 11 October 2017 (UTC)

And if there are a lot of disagreements, somebody is going to be doing some serious research regarding who is right and why some nodes are giving wrong answers. Is it some sort of conspiracy? Did we just discover something like the Pentium FDIV bug? are two different revisions of our code giving us different answers when the changes supposedly didn't effect the math? --Guy Macon (talk) 09:49, 11 October 2017 (UTC)

Tetris Friends

Does anyone know where that site is hosted?--Tuchiel (talk) 12:58, 11 October 2017 (UTC)

Texas. -- Finlay McWalter··–·Talk 13:09, 11 October 2017 (UTC)

Interesting, thanks a lot!--Tuchiel (talk) 13:17, 11 October 2017 (UTC)

Mobile Internet / Data

I possess "Sony XA Ultra Dual". I'm failing to turn on my "Whatsapp". I've topped-up my simcard, turned on my data roaming and mobile data option, still it states that I don't have internet connection as I press "NEXT" in the "Whatsapp" app, on the mobile phone entry page.

The network provider sent me two messages, first one fails to install everytime, second one was about "MMS" that successfully installs everytime...

I've also tried the 'built-in' option available on the phone that downloads the internet setting automatically, but was unsuccessful as it requests for internet connection.

I have a gut feeling that I would need internet connection (Wifi connection or something alike rather than just the mobile data) for the first time... If untrue, please guide me...

202.134.9.136 (talk) 16:23, 11 October 2017 (UTC)

Very few things need a wifi connection instead of mobile data (both of which would normally be internet connections) for the first time, although some may recommend it if they download a lot of data the first time. WhatsApp however should not need this. But anyway you seem to be putting the cart before the horse. It doesn't sound like you even know the internet is working on your phone (via mobile data). If you are having problems in one app which appears to suggest a lack of an internet connection, you should always try another and make sure the internet is actually working. Probably the best app to try would generally be the browser and visit something like a prominent search engine and make sure it's working (e.g. do a simple search which can't be just a saved page). If the internet is working, on the browser (and you can try another app too for good measure), then there's probably no reason to worry about the APN settings. If do need to change the settings and can't get the automatic ones to work, you could simply find out what they are supposed to be and manually enter then. You're obviously using internet now so could easily just do a simple search and find out what the settings should be. Nil Einne (talk) 18:05, 11 October 2017 (UTC)

I've checked it using Opera Mini and Chrome, the internet doesn't work at all. What should I do? 202.134.13.133 (talk) 19:17, 11 October 2017 (UTC)

Perhaps there is no reception. There may be some incompatibility, eg phone only does 2G, but sim and provider only have a 3G available. If it si a dual sim phone this can happen, you may be able to change positions. Another thing to check is if there is a usage limit. Note that in SIMs I have used it never has to "set up" with a SMS or MMS message, so I wonder if this has gone wrong and set the connection into some bozo mode. Graeme Bartlett (talk) 21:02, 11 October 2017 (UTC)