Wikipedia:Reference desk/Computing

The Wikipedia Reference Desk covering the topic of computing.
Computing #eee #f5f5f5 #eee #aaa #aaa #aaa #00f #36b #000 #00f computing Wikipedia:Reference desk/Computing Computing WP:RD/C

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January 2

Ceramic disk capacitor size?

Hello,

I have a (broken) capacitor that I would like to know the size of. I believe it is ceramic disk type, it is black and has the letters "TP" on one line, with "8D13" written below that. I have looked online and cannot find anywhere how to figure what size capacitor this is? Thank you for any help. Elpenmaster (talk) 02:58, 2 January 2015 (UTC)

It's not this, is it?:

http://www.datasheet-pdf.com/datasheet/GeneralElectric/678931/TP8D13.pdf.html

But it doesn't seem to be a capacitor... 109.153.236.190 (talk) 03:21, 2 January 2015 (UTC)

Yes, that's it. I guess it is not a capacitor after all Elpenmaster (talk) 17:36, 2 January 2015 (UTC)

Zipping Files with 7Zip

I am cleaning my computer and I have found a lot of stuff that I dont want to delete and I was wondering if I could just zip the folders I want to keep for a long time in .7z I am worried about something going wrong down the line and I wont be able to get my data out of the .7z file so that I can use it again. Is this a crazy fear of mine? I have been zipping up my favorite folders with family pictures and documents that will be important 10 years from now, does .7z corrupt a lot? — Preceding unsigned comment added by 204.42.31.250 (talk) 10:37, 2 January 2015 (UTC)

All backups can go wrong, but 7Z is not particularly susceptible to corruption, and should still be available in ten years time. If the files are important, I'd be inclined to keep a separate uncompressed backup on a separate backup hard drive or DVD data disc. (My paranoia leads me to keep at least three separate backups of files that I might want in ten years time.) Dbfirs 13:01, 2 January 2015 (UTC)

I want all these files in 10 years time or longer but if something truly goes wrong and I lose it all its not the end of the world for me I will be very upset at the moment but starting over will be interesting. Hopefully I never have to do that. — Preceding unsigned comment added by 204.42.31.250 (talk) 13:08, 2 January 2015 (UTC)

Disk space is cheap and getting cheaper all the time, so compressing data for backups is rarely worth the effort. Image files are already compressed, so trying to compress them again in a compressed container like 7z will save only a further 1 or 2% - totally not worth the effort. The greatest risks for data loss are accidental deletion (when you forget what the backup is, think it's junk, and delete it) and media failure (hard disk errors, DVD scratches, tape tangles). Compressing and archiving the data on the same medium doesn't protect you from either risk. If you want to have some comfort that this data will be available to you in a decade, you need multiple copies on different media (an external hard disk, a flash drive, a DVD), some of which are offline (they're not connected all the time), some of which are in different locations (e.g. in a safe in a relative's basement). -- Finlay McWalterᚠTalk 13:33, 2 January 2015 (UTC)

7z is an open format, so it should be available for a long time. Besides compression, an archive format like 7z allows you to place related files in a container and provide error checking when decompressed. Finlay McWalter is very correct: redundant backups are what you need for essential data. --  Gadget850 ^talk 14:21, 2 January 2015 (UTC)--  Gadget850 ^talk 14:21, 2 January 2015 (UTC)

Yeah it significantly depends what sort of data you're storing. In my case, I admit I have a recent tendency to save various web pages so I have a personal record without having to rely on third party sites (when I want to show to other parties, I do use archive sites). Over time I can end up with quite a lot of these. I've also used tools like wget sometimes to get a page at regular intervals (e.g. during sales). Over time, this can add up to a lot, but since a lot of the data is redundant and of course the HTML and CSS is often fairly compressible, it definitely does help to compress and archive it. Just as importantly, having 1 million files can cause various performance issues for the file system and for searching (if you don't index the disk except for those places) so archiving helps there too. The OP mentioned documents, so it depends a lot on what sort of documents and how many. If it's just a few thousand or less, you probably aren't going to gain that much in terms of performance or spaace. If you're getting in to 100k documents, perhaps you will. Nil Einne (talk) 14:58, 2 January 2015 (UTC)

The latest stable version of 7-Zip, version 9.20, was released in 2010, and is downloaded over 300,000 times per week on SourceForge alone, and probably significantly more when you include other software download sites. People have compressed a lot of data with it, and I don't think there's been a single case of data corruption attributable to a bug in 7-Zip (otherwise the author would have released a fix). It's really not worth worrying about that. 7-Zip is open source software, and there are so many 7z archives out there that someone will port it to computers of the future, even if the original author doesn't. You are much more likely to have trouble plugging in the hard drive with the 7z archive on it than extracting from the 7z archive.

The only reason not to compress your data is that a single flipped bit in compressed data can snowball to a lot of flipped bits in the decompressed data (and hardware glitches can flip bits). If that worries you, you can still use 7-Zip to archive the files with no compression. That gives you the convenience of having everything bundled in one file and the security of CRC error checking, so you will at least know if a bit got flipped. -- BenRG (talk) 01:45, 4 January 2015 (UTC)

Article on Clipping (computer graphics) in need of attention.

It's in bad shape. I cleaned it up a bit and added a section on Z-clipping, but it still needs work. Any volunteers ? StuRat (talk) 17:17, 2 January 2015 (UTC)

Thanks StuRat. I'll have some spare time over the next weekend and may take a look at the article's condition for a major overhaul. Nimur (talk) 18:45, 2 January 2015 (UTC)

OK, looking forward to those improvements. StuRat (talk) 05:47, 3 January 2015 (UTC)

Well, the weekend drew to a close... there is always more work to be done, but I have completed my most significant changes to content and organization. First and foremost, I have verified the content and definitions by citing (and linking) several texts and online documentation resources. Of course, please feel free to review and edit for accuracy, editorial issues, and so forth. I will probably revisit the article in the next few days with some touch-ups. Nimur (talk) 22:20, 4 January 2015 (UTC)

OK, thanks. A couple questions on your Z-clipping changes:

1) Why did you remove my mention of using one or two dials as one method to control the Z-clipping planes ?

2) Your example of using a tall wall to hide game elements to improve performance seems to be something other than Z-clipping, so I suggest another section. StuRat (talk) 22:31, 4 January 2015 (UTC)

The answer to both questions is that I attempted to make the article "technology-agnostic"; the two "dials" you refer to match implementations like OpenGL's camera perspective API, but are not universal in all APIs and all platforms. The same goes for the second question: one single z-buffer in a modern GPU can be used for both occlusion- and for distance-tests (e.g., "zNear" and "zFar" in OpenGL, which are the instances of your "dials" in that API)... so these are arguably the "same" feature. The gory details are, of course, implementation specific. If you'd like to dive deep into those details, please feel free to amend what I wrote, and cite sources! Nimur (talk) 23:15, 4 January 2015 (UTC)

Well, I'm a bit concerned that it's no longer readable by a general audience, and details like using dials to adjust the clipping planes help to make it more understandable to the masses. Some pics would also help. StuRat (talk) 23:20, 4 January 2015 (UTC)

Please let me know which parts are inaccessible to a general audience. I have been making a best effort to describe the process in plain language, and use wikilinks when appropriate; but I am not always aware when a phrase or term would be unfamiliar to the uninitiated. Nimur (talk) 00:10, 5 January 2015 (UTC)

"This viewport is defined by the geometry of the viewing frustum, and parameterizes the field of view." Wow, I couldn't make a simple subject sound any more complicated if I tried. StuRat (talk) 04:49, 6 January 2015 (UTC)

This sentence is evidently confusing to you. To me, it is written in plain English: it accurately and concisely states a factual relationship between several important concepts.

I am not able to refactor the sentence to be any more simple, except to add wikilinks for viewport, geometry, viewing frustum, and field of view.... and possibly the word "parameterizes". I admit that these technical terms might be unfamiliar to some people; but how can we describe a relationship between these nouns to somebody who does not know what these nouns even mean? (In my defense, I did paraphrase the definitions of each of those terms in the lead-up to the sentence that is confusing to you).

Perhaps we need a third opinion, as I am not able to satisfactorily explain the concept in a way that is understandable. Nimur (talk) 17:21, 6 January 2015 (UTC)

OK, does anyone else think the above sentence is simple to understand by a general audience ? StuRat (talk) 02:27, 8 January 2015 (UTC)

This reply is about the sentence "This viewport is defined by the geometry of the viewing frustum, and parameterizes the field of view." With wikilinks for the expressions "viewport", "geometry", "viewing frustum", "field of view", and "parameterizes", the sentence seems to be simple to understand by a general audience, if a reader unfamiliar with those expressions follows those links and allows enough time to digest their meanings, both independently and in the context of the sentence.

—Wavelength (talk) 21:22, 9 January 2015 (UTC)

The usual problem with sentences that require following links to understand is that those links also contain similar sentences, which require following more links, ad infinitum. Hence the need for sentences that can be understood on their own. StuRat (talk) 22:07, 9 January 2015 (UTC)

A writer can aim for a finite (and minimum) number of necessary clicks to more-basic definitions and explanations. However, condensing complex concepts has limits.

—Wavelength (talk) 03:38, 10 January 2015 (UTC)

Percent-encoding and mojibake, once again

Per a request at WP:AN, I've just created 🇳🇱 as a redirect to Flag of the Netherlands; it's an emoji thing that displays a picture of the flag in some contexts. When I edit the page, I'm taken to https://en.wikipedia.org/w/index.php?title=%F0%9F%87%B3%F0%9F%87%B1&action=edit, and going to https://en.wikipedia.org/w/index.php?title=%F0%9F%87%B3%F0%9F%87%B1 takes me to the right place. However, if I chop off one percent-encoded character (https://en.wikipedia.org/w/index.php?title=%F0%9F%87%B3%F0%9F%87), I end up at П‡³ðŸ‡, which itself has a much longer URL, https://en.wikipedia.org/wiki/%C3%90%C5%B8%E2%80%A1%C2%B3%C3%B0%C5%B8%E2%80%A1. Finally, when I chop that page's final character (%A1), I end up at ߇³ðŸâ€. Three questions arise:

1. %F0%9F%87%B3 translates to 🇳, and %F0%9F%87 translates to П‡. Why doesn't %F0%9F%87%B3%F0%9F%87 take me to 🇳П‡?
2. Why does the URL change from %F0%9F%87%B3%F0%9F%87 to %C3%90%C5%B8%E2%80%A1%C2%B3%C3%B0%C5%B8%E2%80%A1?
3. Why does chopping %A1 give me a title completely different from П‡³ðŸ‡?

Last June, I asked a different percent-encoding question (thus the title on this question), and BenRG said URLs are supposed to be UTF-8 encoded, and C3 AB is the UTF-8 encoding of U+00EB, "Latin small letter e with diaeresis". AB by itself is not valid UTF-8, and some software somewhere tried to guess what it was supposed to mean. It guessed Latin-1 (or more likely Windows-1252), in which AB stands for U+00AB, "Left-pointing double angle quotation mark". Apparently Ben meant that the display of percent-encoded stuff depends on context and interpretation by the computer; is this the explanation? Nyttend (talk) 18:18, 2 January 2015 (UTC)

See Percent-encoding and UTF-8. The initial %F0 indicates a 4-byte character, but (in your examples) you're only sending 3 bytes. To answer your specific questions:

1. The "%F0%9F%87" isn't valid UTF-8 (as you're telling the parser it's 4-byte, but only giving it 3). The parser then considers the whole sequence as invalid (which it is), and instead interprets it as seven single-byte Windows-1252 characters.
2. This is the result of encoding the seven-character string as seven UTF-8 characters, some of which are 2-byte and some of which are 3-byte: %C3%90 [Ð] %C5%B8 [Ÿ] %E2%80%A1 [‡] %C2%B3 [³] %C3%B0 [ð] %C5%B8 [Ÿ] %E2%80%A1 [‡].
3. Removing the %A1 means the entire string isn't valid UTF-8, so the whole string is reinterpreted. It's the equivalent of changing the "MZ" to "MX" in an .EXE file. Tevildo (talk) 10:41, 3 January 2015 (UTC)

Just to clarify on #3, you're again going from UTF-8 to Windows-1252, so the URL with the missing %A1, which started as seven UTF-8 characters (16 bytes) is reinterpreted as fifteen Windows-1252 characters. Tevildo (talk) 15:22, 3 January 2015 (UTC)

And just to clarify further, that behavior isn't in any sense correct, it's just how the author of some code running on Wikipedia servers (possibly MediaWiki itself) decided to handle this situation, once upon a time. Different software might interpret the same URL differently, including decoding the valid UTF-8 sequences as UTF-8 (as you originally expected to happen). Case in point: when I navigated to ...?title=%F0%9F%87%B3%F0%9F%87 with Firefox's network monitor window open, it showed the URL as ...?title=🇳 – that is, it interpreted the valid UTF-8 sequence as UTF-8 and apparently just discarded the rest. When I navigated to ...?title=%80, the network monitor window showed it as a box with 0080 in it (meaning it interpreted it as Latin-1, where 0x80 means U+0080), but Wikipedia took me to Euro sign (meaning it interpreted it as Windows-1252, where 0x80 means U+20AC).

It looks like both Wikipedia's and Firefox's behavior here is explicitly forbidden by RFC 3987 section 3.2, last paragraph. They should probably follow the procedure described in that section, which decodes valid UTF-8 sequences and leaves everything else alone (so %F0%9F%87%B3%F0%9F%87 would decode to 🇳%F0%9F%87). -- BenRG (talk) 19:19, 4 January 2015 (UTC)

Non-mathematical part of good programming

What field of computer science, if any at all, deals with good programming practices? I mean, what discipline analyzes what makes good code good code, independent of language, but not including algorithms and picking the right data structure and technical stuff like that.--Noopolo (talk) 20:57, 2 January 2015 (UTC)

There are no specialized "fields" of computer science that deal with them, because computer science is always about "technical" things. They are social programming conventions, such as:

• Formatting: Indentation/braces, comments, naming conventions, etc.
• Structure: Organization of "code fragments" (functions, classes, modules/source files, etc.).

Czech is Cyrillized (talk) 11:46, 3 January 2015 (UTC)

This is an area that tends to get left out of computer science or engineering. Things like how big a persons desk is, how their interactions with others is organized and how often they are interrupted unexpectedly, how quiet it is, how good the lighting is, whether the air is fresh, how problems are raised, how timescales are set, how the main aims are expressed, ... it goes on ... and on ... these social and environmental aspects can be far more important than any programming standards. Dmcq (talk) 13:56, 3 January 2015 (UTC)

As asked, the question is hard to answer. What makes "good code" in one language may differ when looking at a different language. Functions, classes, etc may be arranged differently depending on which language that you're looking at. So any sort of class on what makes good code will be wrong if it tries to cover every language with one blanket statement. And then some businesses have their own style guidelines about how code should be written which might clash with what other businesses are doing with the same language. e.g. I know you worked for XYZ but here at ABC we want the comments before the line they address not after, etc. Dismas|^(talk) 14:18, 3 January 2015 (UTC)

Software engineering is where the programming takes place (that is why it is "Software" engineering). Inside of that broad field, you will find topics that cover software development, such as project management and programming techniques. As for "what is best" - there is no answer. It depends on who is deciding what is best. For example, I type very quickly and have difficulty keeping my programming as fast as my thinking. So, I don't want to press space-space-space-space to indent. I press tab and use an autoindenter. I think that is best. Many (very very many) are violently opposed to the use of tabs for indentation in code. 199.15.144.250 (talk) 20:01, 5 January 2015 (UTC)

Some aspects of this are more managerial in nature - and would be rather similar for non-software disciples - so (to use that earlier example), the size of someones desk or the number and size of computer monitors they use will probably be very similar for a web designer or a CAD engineer - so that's going to fall into the fields of ergonomics and project management. Some management techniques such as Scrum (software development) are being used more widely than just in software engineering, so those too are migrating out of the "software engineering" discipline.

For the actual day-to-day programming tasks, relatively little of what most people do is related to mathematics. I've spent most of my career doing 3D computer graphics, which is definitely high up on the mathematical scale of things - but even so, I doubt I spend more than maybe 5% of my time "doing mathematics" - most of it is more to do with data structures, data flows, that kind of thing. Algorithms are another activity...somewhat related to the mathematical stuff - but not necessarily.

I don't think there is any sub-field of software engineering that's to do with how to structure code (irrespective of language, algorithms or math)...that's more or less the entire subject!

SteveBaker (talk) 20:13, 5 January 2015 (UTC)

What benchmark to use to measure the speed of a programming language?

What tasks are the more telling towards the aptitudes of a language? Are the methods used to measure numeric problems, different from the methods used to measure symbolic problems? --Noopolo (talk) 20:59, 2 January 2015 (UTC)

Languages don't have speed per se - implementations of the same language can differ by orders of magnitude. But in general, yes, you need benchmarks that reflect the workload you are interested in. Take a look at Standard Performance Evaluation Corporation for a number of different benchmarks they publish. Symbolic systems typically are better represented by SPECint, numerical problems typically better by SPECfp. There are many other benchmarks out there. For your particular interest, take a look at this site. But as the name suggests, this is more for fun than for serious comparisons. --Stephan Schulz (talk) 22:07, 2 January 2015 (UTC)

I'm guessing you mean speed of the program once it is compiled. Going to the limit the fastest language then will always be assembler language. The problem is you've really got to take account of the problem of writing the program, in general more effort on programming means less time on each run. For comparing languages people normally take a not too difficult a problem and ask for it to be coded in a reasonably straightforward way in the different languages. Unless the program is going to run millions of times like on a web server or in computer game or it is a very large problem it isn't normally worth anybody's time to do any optimization. The article Comparison of programming languages gives a comparison of basic features of some languages and might give you some leads. A Google search on terms from there you think are relevant to you might get some actual comparisons that are of interest to you. Dmcq (talk) 13:45, 3 January 2015 (UTC)

User:Dmcq says that to go to the limit of speed after the program is fully compiled one should use assembler language. Of course that depends on the skill of the programmer, and one of the advantages to using a good-quality optimizing compiler is to permit reasonably good programmers, as opposed to super-programmers, to write reasonably performing programs. In in the early 1970's, I remember hearing an assembly language programmer say, about Unisys FORTRAN, that the only way an excellent assembly language programmer could equal the speed of FORTRAN was by using the same techniques as used by the FORTRAN compiler. A good mature procedural-language compiler (maturity meaning time taken to optimize the code) can do almost as well as assembler (which is of course also procedural). As Dmcq says, further optimization isn't useful unless the program will be run thousands or millions of times. Any further optimization (beyond that done by a good compiler) should be done based on the hot-spot principle. It is sometimes called the 80-20 principle, but optimizing the 20% of the code that is run 80% of the time may still not give the return of a 90-10 or 95-5 optimization. Robert McClenon (talk) 15:23, 3 January 2015 (UTC)

January 3

Turning Off Automatic Zip of Attachments

There is a question mentioned above about ZIP in general. This is only very marginally related. I asked this about a month ago, but didn't get an answer to my particular question. I am using Windows 7 and Outlook 14.0.7140.5022. If I originate an email message, and attach a Word or PDF (or probably anything else) file as an attachment, it automatically ZIPs the attachment. I don't want it to do that, and have not succeeded in finding where the option is that says that all attachments are to be zipped by default. I was told that the ability to unzip should be present by default on the computers of the recipients of the email, but I still don't want the default to be to zip the attachment. I only want to zip the attachment if I have explicitly zipped it. Some of my recipients may not be able to figure out how to unzip it, or may have Macs, or may be using mobile tablets on which ZIP isn't readily available. Where is the property set that causes Outlook to zip the attachments by default? Robert McClenon (talk) 16:02, 3 January 2015 (UTC)

Are you sure this has anything to do with Outlook? A simple search for 'outlook zip attachments' suggests this is a feature of WinZIP [1] [2]. Admitedly, I don't know why anyone would bother with WinZIP in this day and age, but perhaps something you installed is doing similar? Microsoft also seems to suggest that this isn't anything to do with Outlook but simply some added component [3]. This suggests QuickView Plus was another culprit at a time [4] although that's even more a case of "does anyone really still use that?" Nil Einne (talk) 16:25, 3 January 2015 (UTC)

Thank you. I have SecureZIP for Windows, which I think is a successor to WINZIP. Does it have a "hook" into Outlook so that it intercepts outgoing email and zips it? Can I turn off that misfeature, or do I have to uninstall SecureZIP for Windows to defeat that misfeature? Robert McClenon (talk) 19:33, 3 January 2015 (UTC)

Dear @Robert McClenon: Dunno. Why not just switch to 7-Zip? It is free and has no such misfeature. —Unforgettableid (talk) 23:49, 3 January 2015 (UTC)

SecureZIP is apparently the successor to PKZIP the original Zip (file format) archiver, made by PKWARE Inc (which was started by the late Phil Katz). WinZip was and is made by a seperate company and originally was simply a GUI for PKZip took off with Windows (at the time Windows had no default support for Zip files), probably because PKWARE took a long time to have a Windows GUI version (I think it was even a while after Windows 95 launched).

Anyway if you look at the SecureZIP support FAQ [5], there is an entry for "Whenever I use Microsoft Outlook® to send an attachment, SecureZIP automatically compresses it. How can I turn off or disable that feature?" although I would also suggest uninstalling SecureZIP if you are unable and don't have a reason to want it.

Nil Einne (talk) 08:15, 4 January 2015 (UTC)

I should clarify I meant to say "I suggest uninstalling SecureZIP if you are able and don't have a reason to want it". My suggestion was based on the fact that I personally feel SecureZIP and WinZIP (or really most paid compression programs) don't provide much useful to most people and are more likely to be annoying compared to alternatives out there. (The exception may be WinRAR, although that only really because it's the only way to compress RAR files, as although 7-zip is frequently a better alternative, there are a few occasions where you may want to use RAR.) I'm fairly sure you should be able to disable the Outlook add-on without uninstallation, even if the FAQ suggestion doesn't work. BTW, since you did I presume pay for this product if you can't work it out it may be worth taking advantage of any email support on offer. Nil Einne (talk) 11:01, 6 January 2015 (UTC)

In your original question there was a reply that suggested WinZip Courier - do you have WinZip Courier installed? 175.45.116.61 (talk) 00:20, 6 January 2015 (UTC)

Adjustable windows

(This is related to the previous discussion "Transparent windows".)
Google Maps makes it possible for visitors to resize maps ("zoom in" and "zoom out") and to shift the region shown ("pan" in any direction). I am not aware of Google Maps or any other website making it possible for a visitor to adjust the map projection.
I am visualizing a Wikipedia page of California maps, including a map of California soils and a map of California vegetation. If a visitor wishes to drag the vegetation map and superimpose it over the soil map, it is necessary that both maps show the same region with the same scale and the same map projection and the same orientation. If rotation is possible, then that can adjust the orientation. For the scale, there could be three options: (1) using a slider, (2) using plus-sign and minus-sign buttons, and (3) entering a ratio, such as 1:100,000 (1 cm represents 1 km) or 1:63,360 (1 inch represents 1 mile). A map projection might be selected from a drop-down list, but this operation might be technically the most difficult of these to enable.
Which of those operations are technically possible with MediaWiki?
—Wavelength (talk) 17:47, 3 January 2015 (UTC)

Note that another common way to change the map scale is the mouse wheel. Also, as far as making sure both maps match, the easiest way might be to grab all the params from the stationary map, and apply those to whatever map is dragged onto it. StuRat (talk) 17:52, 3 January 2015 (UTC)

Which websites illustrate those operations as you have described them?

—Wavelength (talk) 01:20, 4 January 2015 (UTC)

Google Maps uses the mouse wheel to zoom in and out. I don't know of an example that uses my proposed drag and drop map overlay method. StuRat (talk) 21:37, 4 January 2015 (UTC)

Thank you for your replies.

—Wavelength (talk) 00:17, 5 January 2015 (UTC)

New ad problem with comic strips

I don't know whether this is unique to my being at home, or whether it's just a coincidence. Once the library nearest my house is open again I'll be using a computer there to go to Gocomics.com. What has been appearing a lot lately is:

Do you want to open or save dvtp_src.js from cdn.doubleverify.com?

If I click on the x at the right, I get:

Do you want to open or save OAD_Comscore_NoID2.js from secure-ds.serving-sys.com?

Is this something to be concerned about?— Vchimpanzee • talk • contributions • 18:05, 3 January 2015 (UTC)

You might tell the librarian about it. It looks like some malware has installed on the PC, but that the security settings do allow you to verify if you want to install more of their junk. Or perhaps those are just normal files that some of the software tries to download. In any case, it's annoying, so they might want to change their security settings a bit. However, there's some risk that it may be the site you are using that's trying to download that junk, and that they therefore may block it. StuRat (talk) 19:07, 3 January 2015 (UTC)

I am at home, but thanks. Once I can go to the library tomorrow, I won't be going to the site at home.— Vchimpanzee • talk • contributions • 18:46, 4 January 2015 (UTC)

It keeps happening (still at home) and sometimes the order is reversed but I think it's the same two messages. I also got the pair of messages once on Uexpress.— Vchimpanzee • talk • contributions • 19:55, 4 January 2015 (UTC)

It did not happen at the library. And as far as I know, that library will not close again until a weekend in March, so I don't have to go to the site at home until then. I am going to report this to gocomics.— Vchimpanzee • talk • contributions • 20:24, 5 January 2015 (UTC)

Done. I'll report back if they have anything to say.— Vchimpanzee • talk • contributions • 20:48, 5 January 2015 (UTC)

┌────────────────────────────────────────────────────────────────────────────────────────────────────┘Universal Uclick Support, Jan 05 03:12 PM:

Hello,

These are not from our site, and must be the result of spam software on your browser.

Please let us know if you have any additional questions.

Thank you, GoComics Support a Universal Uclick Service

Of course they won't take credit. They get advertising from people who pull these stunts, and then they say, "It's not our fault."— Vchimpanzee • talk • contributions • 14:20, 6 January 2015 (UTC)

I didn't document exactly what happened, but at the library, it happened with the Pittsburgh Post-Gazette.— Vchimpanzee • talk • contributions • 21:30, 7 January 2015 (UTC)

January 4

Credit Card Processing

Say I have a simple application to acts a cash register, on a desktop computer, and can receive credit cards via a usb swiper, how would I go about actually processing the cards, charging them, etc.? More clearly: what would I need to do this in the situation described, what services might I need to use, what info would I need (merchant accounts, etc.), and how would I get started doing this programmatically? I realize that's a lot, but I'm not looking for a full answer, just a few leads that can get me started - when I've looked this up, I'm not 100% sure what all I need to be looking for, so any direction would be helpful. Thank you:-)Phoenixia1177 (talk) 06:29, 30 December 2014 (UTC)

Merchant account has quite a bit of information. Or Google search for something like "small business credit card processing".--Shantavira|^{feed me} 08:36, 30 December 2014 (UTC)

Phoenixia1177 BTW, it is very rare these days to run that kind of application from a desktop computer. I would recommend using a hosting service such as Godaddy or Google sites. Google was free last time I used it and Godaddy is free or very cheap. Those are just two there are many others and most of them already have various built in widgets for doing basic things like processing credit card info. Here are some links I found: http://basicblogtips.com/credit-card-processing-alternatives.html https://developers.google.com/wallet/instant-buy/ http://credit-card-processing-review.toptenreviews.com/google-checkouts-credit-card-processing.html --MadScientistX11 (talk) 18:50, 30 December 2014 (UTC)

Dear Phoenixia1177:

Ah, card acceptance! A confusing jungle of options.

I don't live in the US, so it's hard for me to advise you. Here's the best advice I can give anyway.

Your user page says you live in the state of Pennsylvania in the US and you manage a hotel. So you definitely want to accept Visa and MasterCard. Maybe also American Express, though I hear they charge higher "interchange fees" to merchants which accept their cards than Visa and MasterCard do. (Are there other types of credit cards which are issued overseas but not issued in the US? I dunno. Visa and MasterCard are pretty common in a variety of English-speaking countries.)

As for debit cards: It's good (but not crucial) for you to be able to connect to one of the classical debit interbank networks, such as Pulse, NYCE, MAC, Tyme, SHAZAM, or STAR. (You may only need to connect to one debit network, since many of them are interconnected with each other.) They charge lower fees than Visa Debit and MasterCard Debit do. See Debit card#United States.

So, what are your options? As I see it, you have three options.

• One option is an Android or iPhone card-acceptance app, plus (optionally) a mobile swiper doodad. It's easy to sign up. These tend to have zero monthly fee and high fees per swipe (about 3%). You can buy a swiper for $10. Since the monthly fees are so low, customer service may not be very good. If you run into problems with funds being held, it might be hard to get them released faster. These apps may not connect to the debit interbank networks at all.
• Another option is something PC-based like PayPal Virtual Terminal. You pay a monthly fee and get better customer service.
• A third option, and I think the most common choice of hotel owners, is to buy or rent a card-processing machine and to get a traditional merchant account. Highest monthly fees and lowest per-swipe fees. Signing up can be a big hassle. (They want to make sure that your hotel is in good financial shape, since they're in big trouble if you go bankrupt.) Many traditional merchant accounts are connected to one of the classical debit networks. Amad Ebrahimi of the Merchant Maverick website advises, "Negotiate yourself a good interchange-plus rate with a processor that doesn’t charge an early termination fee". I advise you to consider buying a card-processing machine upfront instead of paying higher monthly fees in order to get a "free" one. Nothing is ever truly free. :)

Regarding surcharging: Ever since the Payment Card Interchange Fee and Merchant Discount Antitrust Litigation was settled, it's been permissible for merchants in many states to charge customers a surcharge to help cover credit-card processing fees. I'm not sure whether or not this is allowed in Pennsylvania. I'm also not sure whether or not your guests will be annoyed or not.

How big is your hotel? How long has it been in business? Has it ever accepted credit cards before? How much money do you expect to be charging to credit cards per month?

Kind regards, —Unforgettableid (talk) 19:57, 30 December 2014 (UTC)

How long does a temporary ban last on a wiki website

Thank you. Venustar84 (talk) 00:04, 4 January 2015 (UTC)

What website? What ban? Your question is so vague as to be unanswerable. AndyTheGrump (talk) 00:30, 4 January 2015 (UTC)

It's all right there on your talk page, User talk:Venustar84. Either ask the administrator who imposed the ban, or appeal the ban to the community at WP:AN. Robert McClenon (talk) 01:41, 4 January 2015 (UTC)

But in either case, be sure to address the original issues, or you can expect to be ignored. Robert McClenon (talk) 01:46, 4 January 2015 (UTC)

It's not on wikipedia. It's on wikimoon.org Venustar84 (talk) 02:46, 4 January 2015 (UTC)

We have no control over wikimoon.org. Why did you think that two wikis with different domain names were related? Robert McClenon (talk) 02:48, 4 January 2015 (UTC)

@Robert McClenon: It's not too uncommon for people to associate other wikis with Wikipedia, especially since we have sister projects.

@Venustar84: Wikimoon is not associated with Wikipedia or the Wikimedia Foundation, so I'm afraid you won't find much help here. Wikimoon should have its own policies on how blocks and bans work - you'll have to reach out to the editors or the administration there to answer your question. ~SuperHamster Talk Contribs 02:50, 4 January 2015 (UTC)

As Superhamster says, the same general answer applies to wikimoon as to Wikipedia: Ask the person or persons who imposed the ban. Robert McClenon (talk) 03:07, 4 January 2015 (UTC)

Here is Wikimoon's block policy. It seems very informal and somewhat arbitrary. Here is also the block log for Wikimoon. So it seems that on that project that the duration varies widely. I can't speak for projects outside of the Wikimedia Foundation like Wikimoon. But, in general, it depends on whether you've been banned before and on the severity of the offense. For minor offenses (e.g., vandalism), it's usually 24 hours for the first block. They typically refer to these as "blocks" instead of a "ban." A ban typically denotes something permanent, although banned users are often allowed to return after several months or even years. A long-term ban usually requires community consensus on Wikimedia projects, and it's usually for more serious offenses (e.g., long-term vandalism, death threats, etc.). However, on less-formal wikis I've seen people banned permanently on the spot by just a single administrator. In any case, if you recognize your IP address or user name in that log, it will tell you the duration of the block. Maybe you could leave a message on your own talk page asking the administrator about it. I'm sure they would see it in the recent changes since it's such a small wiki. Unfortunately, they don't seem to support e-mail, so you will have to use a talk page.—Best Dog Ever (talk) 04:01, 4 January 2015 (UTC)

Two questions related to Vagrant

I'm using the 64-bit edition of Windows 8. I'm considering installing Vagrant. Please answer each question in its own subsection. Thank you, —Unforgettableid (talk) 05:57, 30 December 2014 (UTC)

Installing Vagrant into a directory with spaces in its name

The installer asked me where it should install itself, and suggested "C:\HashiCorp\Vagrant". I don't know why it didn't suggest installing itself into either "C:\Program Files\Vagrant" or "C:\Program Files (x86)\Vagrant". Is there any disadvantage to installing Vagrant into a directory with spaces in its name? Regards, —Unforgettableid (talk) 05:57, 30 December 2014 (UTC)

Not to my knowledge. ☃ Unicodesnowman (talk) 16:08, 1 January 2015 (UTC)

Dear @Unicodesnowman: Thank you for your answer. If I may ask: Have you ever tried installing it into such a directory? Alternatively, are you active in the Vagrant community and have never heard anything bad about the practice? Cheers, —Unforgettableid (talk) 04:45, 4 January 2015 (UTC)

Vagrant versus VirtualBox

Really, I just want to install and use Ubuntu or Debian on this PC. Cygwin isn't ideal: operations such as "tar xzf" tend to be kind of slow inside Cygwin. I don't want to dual-boot: it's a shared PC, I don't want to force anyone else onto Linux, and I want Windows fast user switching to always be available. I'm familiar with VirtualBox; I've never actually used Vagrant. Plus, the VirtualBox Windows installer is 100% open-source; the same cannot be said of the Vagrant Windows installer. What would I lose if I simply installed plain old VirtualBox and downloaded a prebuilt virtual machine image from the Ubuntu website? Regards, —Unforgettableid (talk) 05:57, 30 December 2014 (UTC)

I have never run anything on top of Windows (I like solid foundations), but I've run XP on top of Red Hat and CentOS in VirtualBox, and I'm running (though use it rarely) Ubuntu on top of OS-X in VirtualBox. If you install the non-free (but no-cost) Guest Additions and go full screen, the experience is very nearly native. Sorting out networking can be trial-and-error, but otherwise, it always worked fine for me. --Stephan Schulz (talk) 09:30, 31 December 2014 (UTC)

I regularly run Ubuntu VMs in VirtualBox on top of Windows and it works fine. The only glitch to note is to do with the user switching that you mention - switching users will disconnect your VMs from the network (and that includes connecting as the same user by remote desktop). Otherwise, it's been a pretty flawless experience for me, with the usual caveats re virtual machines, ie more RAM is better, faster disk is better, more CPU cores is better, in roughly that order. GoldenRing (talk) 10:10, 31 December 2014 (UTC)

Dear @GoldenRing: Thank you for your reply. Still, maybe I will use VirtualBox instead of Vagrant after all. About the glitch: Interesting. Have you reported this in the VirtualBox bugtracker? Cheers, —Unforgettableid (talk) 04:17, 4 January 2015 (UTC)

@Unforgettableid: It is discussed in the forums. It seems the limitation is fundamental to Windows (Windows 7 in this instance). When you log on as a different user, or by remote desktop, all the existing programs lose network connectivity. See eg [6]. GoldenRing (talk) 05:33, 4 January 2015 (UTC)

Relocating 'Recycle Bin'

Hi friends,

Hope you are all well, had a lovely Christmas and a New Year party celebration.

I’m back from my holidays…

I have a question to ask: I would like to know if there is a possibility relocating the desktop’s ‘Recycle Bin’ icons folder to a RHDD (Removable Hard Disk Drive), so that every time I insert something in the desktop ‘Recycle Bin’ icons folder it goes straight to the RHDD. I don’t wish to create a ‘Recycle Bin’ icons folder manually in the RHDD then insert a 'shortcut icon in the desktop, I only wish to relocate the path location of the actual ‘Recycle Bin’ icons folder that is available in the desktop already.

Can anyone help me please?

(Russell.mo (talk) 07:38, 4 January 2015 (UTC))

Firstly, the recycle in isn't stored on the desktop. It's store on the root of each partition as a "$Recycle.Bin" directory (well on new versions of Windows, on older it had a different name but was still in the root). Even though it may look like you only have one recycle bin, in reality each partition if you have multiple has their own seperate recycle bin. The only thing stored on the desktop is a shortcut to the recycle bin in explorer. See Trash (computing)#Microsoft Windows. Anyway as for moving the recycle bin, I'm fairly sure it's not possible. The recycle bin in Windows simply isn't designed like that. See [7] for example. However Explorer replacements or even Explorer shell extensions may be able to make their own recycle bin which functions like that although it still wouldn't help with other programs which use the API or otherwise move stuff to the recycle bin. You could probably also find something which will move stuff to another partition after they are moved to the recycle bin. You could try turning the recycle bin directory in whatever partition you're referring to in to a NTFS symbolic link which works for many things but I suspect in this case it will just break stuff. Nil Einne (talk) 07:51, 4 January 2015 (UTC)

@Nil Einne: I thought and noticed some of the things you mentioned... I understand. Thanks. I'll read through the links you provded. -- (Russell.mo (talk) 08:01, 4 January 2015 (UTC))

Yes, it's all "smoke and mirrors". The recycle bin just reserves the space where the file is still stored, and makes it easier to put the links back to the original logical folder. The "deleted" file is still there in its original physical place; it's not actually moved to anywhere else. If you want files to be stored in a recycle bin on a different drive, you will need to move them to that drive before deleting them. The space on the original drive will then be marked as available, but you will no longer have the easy one-click option of restoring to the original folder. Dbfirs 09:09, 4 January 2015 (UTC)

I guess this cleared a few things. I'm actually saving files and folders on the Recycle Bin's folder based on the desktop, whenever I need to reuse a file I kind of drag and drop it in the Wallpaper, when no longer required I throw it in the Recycle Bin again. I think this is the reason why my C drive look s almost full... -- (Russell.mo (talk) 17:40, 4 January 2015 (UTC))

When you drag a file to the recycle bin, nothing moves. The process is exactly the same as clicking delete, but all that happens is that the file details are stored in a file called "Recycle bin", whilst the file stays exactly where it was. If you are dragging files, why not create a folder on your removable drive with a shortcut on the desktop, then you can use this folder in exactly the way you have been using the recycle bin. You will notice a difference in the time it takes for big files because in this arrangement the contents of the file are actually moved from one drive to the other when you drag. Dbfirs 21:32, 4 January 2015 (UTC)

Yeah, that's when the "$Recycle.Bin" folders come into action... I get what you are saying... There is no other option rather than what you mentioned to make the use of Recycle Bin. Thanks. I'll create a shortcut in the desktop and insert the original in the RHDD, and probably have to watch out for the bigger files, not to insert it in the recycle bin...

Thank you both

Resolved

Call of Duty 'game controlling issue'

Hello!

I recently received a gift of a game called ‘Call of Duty Modern Warefare 1 & 2’ without a setup file. The game functions alright, I failed to connect my playstation ‘plug n play’ controller. The game(s) seem to not possess the option of selecting different controllers nor does the plug and play option of the controller functions. Is there a possibility setting up the playstation ‘plug n play’ controller manually?

(Russell.mo (talk) 07:42, 4 January 2015 (UTC))

Building a package on Linux

I tried to build the newest version of the hid-atari-retrobit package on Fedora 20 Linux, but I got this error message:

make -C /lib/modules/`uname -r`/build M=$PWD modules
make: *** /lib/modules/3.16.2-201.fc20.x86_64/build: No such file or directory.  Stop.
make: *** [all] Error 2

Can anyone help? JIP | Talk 07:48, 4 January 2015 (UTC)

Never mind, it turned out I had to install the kernel development package first. JIP | Talk 17:04, 4 January 2015 (UTC)

USB Pen Drive issue

I have an 8 GB ‘USB pen drive’ which display the ‘format disk’ window every time I plug it in. When formatted, which takes a long time, well it fails to format the USB pen drive’. I am able to ‘safely remove’ the ‘USB pen drive’ by ‘right clicking’ from the ‘notification bar’ based on the bottom right hand side of the monitor screen. If I replug and cancel the formatting option ‘window’ that appears straight after replugging, it displays ‘Removable Disk (U)’ or ‘RAW (U)’ whatever it feels like whenever it is replugged in the ‘My Computer’ window. How can this issue be fixed? I tried everything possible but failed after utter trying.

Reason of this porblamatic cause: Once I was formatting the ‘USB pen drive’, everything froze in the Monitor screen. I thought the cause was the ‘USB pen drive’ therefor I manually unplugged it while it was formatting. The display screen was still frozen but started functioning after (5/6 seconds later) the ‘USB pen drive’ was unplugged. I replugged to reformat it then the same thing occurred, it froze again. I unplugged and replugged a few times while it was formatting as it kept on freezing and now it doesn't format any more, doesn't mount either…

Note: I have formatted several times but it doesn’t format, I tried the 'MS Dos' style format and it doesn’t work, I tried mounting, changed the drive letter as defined in the internet while I was trying to fix it; basically I tried everything and I still don’t wish to give up, and I need help… When I ‘click’ the ‘Start’ menu from the bottom left hand side bar of the monitor screen, I type ‘Computer Management’ and press ‘enter’, thereafter the ‘Computer Management’ window appears. I ‘click’ the ‘Disk Management’ option from the ‘left pane’, all the information appears on the ‘middle pane’, I review the ‘U’ drive’s information available in the ‘bottom middle pane’, it says, ‘7.45GB RAW Healthy (Primary Partation)’ and possess diagonal lines in the box where it says.

I need help in fixing it so that it starts functioning. Any ideas?

(Russell.mo (talk) 08:04, 4 January 2015 (UTC))

Does the issue affect other thumb drives that you plug into the same port? If not, then it's probably a hardware problem with the thumb drive. Does the issue happen if you plug it into a different computer? If not, then the drive is probably fine and it's some other issue with the USB port or OS.—Best Dog Ever (talk) 12:23, 4 January 2015 (UTC)

@Best Dog Ever: I'm guessing that it could be a hardware problem. Everything else you mentioned, tested and is on the positive side. Any idea how to mitigate the hardware issue? -- (Russell.mo (talk) 17:29, 4 January 2015 (UTC))

It might be just a bad connection, so I suppose you could try taking it apart carefully, but if the problem is in the write or control circuitry then it's probably not worth repairing because a replacement costs very little. Dbfirs 20:38, 4 January 2015 (UTC)

I've heard of people resoldering on the USB connector for bad thumb drives. (Here are some tutorials covering that that you can try, assuming that's the problem.) If the board itself is bad, then most repair shops will just remove the flash-memory chips and connect them to another drive for data recovery. However, since you're not trying to recover the data and since it's only an 8 GB drive, then I would just buy another one. They're only about $5.—Best Dog Ever (talk) 21:28, 4 January 2015 (UTC)

You guys are right, it is not worth repairing, right now, as I bought another RDD. Its just, its the first USB drive I bought when I entered this third world country to save datas, during poverty. In other words, I have intimate connection with it (lol). Thanks for the info guys, I'll try to fix it when I get the time, and or might keep it as a show piece. -- (Russell.mo (talk) 04:40, 5 January 2015 (UTC))

Win7Pro Windows explorer view

I am running Win7Pro. I have 2 nominally identical usb data sticks (32GB).

When viewed in windows explorer (in "Details" mode), one has columns

Name Date modified Type Size

the other has columns

Name Type Total size Space free

The former just lists folders and files in order The latter insists on grouping the root directory into types of file.

How do I stop the latter doing this and make it like the first stick. (I have at some point in the past formatted the second stick as FAT32, which is the same property that the first unreformatted stick claims.)

-- SGBailey (talk) 11:51, 4 January 2015 (UTC)

I've manually changed the column titles back to the normal selection (unsure whether it will remain like that as yet) but it still groups things with a little "heading" in th list of files. That in particular is what I want to stop. -- SGBailey (talk) 11:56, 4 January 2015 (UTC)

Right-click in a blank area of the folder and choose Group by → (None).—Best Dog Ever (talk) 12:11, 4 January 2015 (UTC)

Thanks. For some reason I had to select none twice. The first time it didn't stick and reverted to "Name". -- SGBailey (talk) 17:11, 4 January 2015 (UTC)

SecureZIP Uninstall Error

In response to the discussion above about a problem with SecureZIP, I tried to uninstall SecureZip for Windows, which would be necessary to replace it with 7-Zip. It says: "Error opening installation log file. Please verify that the specified log file location exists and is writeable." What should I do next, short of calling a technician? Where is the file at which I should look? Robert McClenon (talk) 17:46, 4 January 2015 (UTC)

A web search for the error message turned up KB2564571, and while it's quite old (2011), I would nevertheless try killing and restarting Explorer as it suggests, and if that doesn't work (or you don't know how to do it), rebooting. If rebooting doesn't work, you may be in trouble. I don't think you need to uninstall it at all, though. I'm sure there's a way to turn off the email encryption feature. -- BenRG (talk) 19:34, 4 January 2015 (UTC)

On the uninstaller issue, it's probably trying to create a file in the %TEMP% directory, and it may not have sufficient privileges or the directory may not exist. Try running the uninstall program as administrator. If that doesn't work, there may be a command-line option for the uninstaller that tells it not to create a log file - assuming it's called "uninstall.exe", try uninstall /silent or uninstall /?. Tevildo (talk) 21:06, 4 January 2015 (UTC)

Has the installation log file been deleted? Possibly the uninstall routine looks there to see what files and registry entries to delete. You could try reinstalling it to recreate the file, then uninstall. Dbfirs 21:19, 4 January 2015 (UTC)

I've had good results with the free version of Revo Uninstaller, which tries several progressively more aggressive methods of uninstalling a program. -- Finlay McWalterᚠTalk 23:22, 4 January 2015 (UTC)

I was doing the uninstall as administrator. I will try the other suggestions made. By the way, I can't find a way to turn off the automatic zipping of attachments. I would still also appreciate any suggestions there. Robert McClenon (talk) 21:41, 6 January 2015 (UTC)

January 5

Using USB digital joystick adapter on VICE?

I built and installed the "hit-atari-retrobit" package that allows me to use a classic digital Atari-type joystick on a modern Linux PC via USB. E-UAE and FS-UAE recognise it and the joystick works. However, VICE shows no sign of recognising the joystick. The joystick configuration menu only shows keyboard and analog joystick options. How do I configure the USB joystick adapter to use on VICE? JIP | Talk

help required from experienced authors for regarding references

hi sir, i just added the page, https://en.wikipedia.org/wiki/Arowana_Consulting which has been declined due to lack of sources of notability. I added a number of sources but wikipedia accepted only two. kindly help me finding more and please suggest if adding the links to pdf of certifications acquired by the company could be of some help. — Preceding unsigned comment added by Rachelrini2 (talk • contribs) 06:38, 5 January 2015 (UTC)

Most Google hits seem to be self-publicity which is not allowed here. You need to find more mentions of the company in the press to establish notability. Are you an employee of the company? If so, there might be a conflict of interest. Dbfirs 07:54, 5 January 2015 (UTC)

See WP:SPS, if appied, only. --Hans Haase (有问题吗) 11:57, 5 January 2015 (UTC)

Seems to me like this article should be deleted. WP:ORG says that we only have articles about companies that have been written about extensively. We require: "verifiable evidence that the organization or product has attracted the notice of reliable sources unrelated to the organization or product. Notability requires only that these necessary sources have been published". The three so-called references in the article are to a review of a movie made by one of the owners of the company (utterly irrelevant), to a mapping company who happen to have an entry for it (they have an entry for my next door neighbor's wife who makes dresses for little girls...please don't tell me that her business is notable because of that!)...and an entry in WikiBusiness.org - which is a place that anyone can create a record for their own business - essentially self-publishing. So there is absolutely ZERO notability here.

Rather than creating an article, then looking for evidence to defend producing it, instead you should hold off from creating the article until you have the evidence you need. For that reason, this article should be (and almost certainly will be) deleted - and only re-created if evidence of notability is found.

SteveBaker (talk) 18:30, 5 January 2015 (UTC)

(FYI: The article has now been deleted, so the question is moot. SteveBaker (talk) 15:51, 7 January 2015 (UTC))

Mount an external drive in Linux such that non-root can write to it

Linux is quite possibly the most broken family of operating systems when it comes permissions and file systems. All I need to do on Windows and Mac OS X is just plug in my hard drive or flash drive and I can edit files/directories, delete them, and move them around with out fuss. On Linux, I need root privileges to mount something. That part isn't too much of a hassle. What I can't figure out how to do is mount a drive such that my user account can write to it. Using root to do this with just screw up the permissions of the files that I create while running as superuser. Is there anyway to accomplish this without using chown or chmod either? — Melab±1 ☎ 21:19, 5 January 2015 (UTC)

To the best of my knowledge, you do need chown or chmod. With chown, you can tell Linux that the drive belongs to your user account to begin with, so you don't need to worry about getting root access any longer. With chmod, you can add write permission for your user account as well. There is a mount option "user" you can add to your /etc/fstab file as root, that will allow you to mount and umount the external drive without root privileges. This won't affect permissions on the actual files on the drive however. JIP | Talk 21:37, 5 January 2015 (UTC)

What distro are you using? In my experience, most newer distros do something very Mac- or Windows-like when a piece of removable media is inserted, automatically mounting it and opening a folder display on it, with permissions set up so that the current user can access it. And even if you're doing things "old school" -- invoking the mount command by hand, perhaps in conjunction with /etc/fstab entries -- as JIP pointed out, the user mount option in fstab should do just what you want. —Steve Summit (talk) 00:34, 6 January 2015 (UTC)

The minimal installation of Ubuntu 14.10. — Melab±1 ☎ 01:34, 6 January 2015 (UTC)

I use Fedora, which is much less user-friendly than Ubuntu. When I plug in a USB drive, it shows up in my file browser. I click on the USB drive and it mounts so I can read/write to it. This makes me assume that either you are using a very broken version of Ubuntu or you are mounting on the command line as root - meaning that the drive is mounted by root, not by you. If so, make sure you pass the uid of your account to the mount command. Otherwise, it will me mounted as root. 209.149.113.90 (talk) 18:11, 6 January 2015 (UTC)

It's completely command line, so I have to use root. In any case, the graphical version requires root, too, I think. And do you mean "more user friendly"? — Melab±1 ☎ 01:00, 8 January 2015 (UTC)

January 6

Difference between an LFSR and an NLFSR

The gist of feedback shift registers is that several units in an array of registers are used to generate the newest unit after the data has been shifted. But what is the difference between a linear feedback shift register and a nonlinear feedback shift register? Can I get examples of either one? — Melab±1 ☎ 01:32, 6 January 2015 (UTC)

Take a long time and read/re-read linearity § boolean functions very slowly and carefully. It took me three or four read-throughs to decipher, and I'm already very familiar with this type of mathematics!

Linearity is a specific, mathematical property. In the context of boolean algebra, the conventional definition is adapted to the boolean (binary) nature of the inputs and outputs, but it is intuitively the same.

However, like many other mathematical definitions, we can't "simplify" the definition. The mathematical language in our definition is already exactly as succinct as possible to correctly describe what linearity means. So, just spend some time to wrap your head around the meaning of the definition, and intuitively understand why this definition implies certain useful properties and applications. A non-linear equation is harder to invert; if you want to use a shift register for cryptography, this is a useful property. Nimur (talk) 03:16, 6 January 2015 (UTC)

Yeah, well examples in these articles always help. — Melab±1 ☎ 05:42, 6 January 2015 (UTC)

An example of a LFSR is a (not very) pseudorandom bitstream produced by $a_{i+4} = a_i + a_{i+1}$ for $i \ge 0$, with $+$ representing logical exclusive or (addition in $\mathbb{Z}_2$) and $a_0, \ldots, a_3$ being the seed. An example of a NLFSR is something like $a_{i+4} = a_i \times a_{i+1} + a_{i+2}$, with $\times$ representing logical and (multiplication in $\mathbb{Z}_2$). The multiplication of previous bits makes it depend nonlinearly on those bits. Real-world examples are DVD-CSS (a stream cipher using LFSRs) and Trivium (cipher) (a stream cipher using NLFSRs). -- BenRG (talk) 07:12, 6 January 2015 (UTC)

I do not understand that at all. I was hoping for examples in the form of shift registers themselves, like "XOR bits 5 and 7, shift to the right, and fill bit 0 with the previous calculation". — Melab±1 ☎ 16:46, 6 January 2015 (UTC)

Does the sequence $a_n$ represent the register? Is the presence of solely XOR operations that make a feedback shift register linear? — Melab±1 ☎ 16:49, 6 January 2015 (UTC)

No: formally, the bits $a_i$ represent an eigenvector of the linear function. The bits $b_i$ represent one instance of inputs into the function (i.e., any possible example of the values of register bits). So, a represents a characteristic of the function - i.e., the digital circuit; b represent the input to that circuit (i.e. the contents of the register) at any given time. Nimur (talk) 18:54, 6 January 2015 (UTC)

Yes, what makes it linear is that there are only xor operations, and yes, in my notation $a_i$ represents the register. Initially its bits are $a_0a_1a_2a_3$. Then (in my simple LFSR) you xor the leftmost two bits together and shift that value in on the right, pushing the existing bits left (and the leftmost bit into the bit bucket). That gives you $a_1a_2a_3a_4$, where $a_4$ is the xor result. Then you do the same thing, getting $a_2a_3a_4a_5$, and so on. Using different indices for the different register values means that each $a_i$ has one unambiguous value, which is how mathematicians like to do things (and how some languages, like Haskell, do things). The destructive-assignment version would look something like while (true) { temp ← w + x; w ← x; x ← y; y ← z; z ← temp; }, where the bits are now called wxyz. Nimur is talking about something else is his reply above mine, probably the definition in the "Linearity" article. My a has nothing to do with that a and b -- BenRG (talk) 05:38, 7 January 2015 (UTC)

NLFSRs are more random than LFSRs. Is it difficult to construct a secure NLFSR? How about an array of bytes that functions like a linear feedback register? — Melab±1 ☎ 00:59, 8 January 2015 (UTC)

What is the name of that dramatic effect?

Hi there,
I've seen many times,pictures with a dramatic effect.
Does anyone know its name?
https://fbcdn-sphotos-d-a.akamaihd.net/hphotos-ak-xpa1/v/t1.0-9/s720x720/10898278_768211989920203_7270092323090769989_n.jpg?oh=9eb390a0e3db245027e48861f63341ae&oe=553DA691&__gda__=1429152119_8de2849e52b5c407b33fbec7508205d2 Exx8 (talk) 14:09, 6 January 2015 (UTC)

High-dynamic-range imaging -- Finlay McWalterᚠTalk 14:11, 6 January 2015 (UTC)

For additional clarification, as explained in that article, the actual images shown tend to be HDR images (perhaps constructed from multiple exposures) that have had Tone mapping to try and simulate display with a medium only capable of a much more limited dynamic range. Nil Einne (talk) 15:19, 6 January 2015 (UTC)

Basically, neither a camera nor a computer screen can capture the very brightest light and the very dimmest at the same time. Parts of a natural image are always either over-exposed or under-exposed. Human eyes are MUCH better at that kind of thing - which is why conventional photography often fails to capture the beauty of a sunset or some other kind of dramatic natural lighting. By taking a bunch of photos of the exact same scene at different exposure settings, then combining the best parts of each of them, you can get closer to something that we see with our own eyes. SteveBaker (talk) 15:50, 7 January 2015 (UTC)

... more aptly, you can produce an image that is closer to what our visual perception makes our brain think we see with our own eyes. In actual fact, our eyes have a slightly wider color gamut and a somewhat wider dynamic range than most camera sensors, but we think our eyes have a near-infinite dynamic range because of the way our psychology distorts the actual signals produced by the biological photochemicals and the nerve impulses in our eyes. Our article on visual perception is a great place to start reading. Nimur (talk) 16:21, 7 January 2015 (UTC)

That makes me think we actually never get to see what our eyes really see, because our brains have evolved to enhance and correct the image on the fly so well we can't even turn it off. JIP | Talk 19:20, 7 January 2015 (UTC)

That's certainly true. We can't distinguish a spectrally pure shade of yellow light (eg from a Sodium lamp) from a mixture of pure red and pure green light that happen to produce the same visual effect. So for sure, we can't see more than a tiny, tiny amount of the information contained in the visible spectrum. That's a limitation of our eyes that our brains try to fudge over by making the best guess as to what a particular combination of red, green and blue "really" is. There are many other examples of that. There is simply not enough bandwidth available through the optic nerve to send a few million pixels of data every dozen or so milliseconds - so you know that a lot of that data has to be lost in the compression done on the data. That becomes evident when (for example) you convert an image from PNG to JPEG and it looks pretty much the same - despite the fact that maybe 90 to 95% of the data was thrown away. That only works because the JPEG encoding standard throws away stuff like high frequency color variations at near-constant brightness that our brains can't detect. SteveBaker (talk) 21:21, 7 January 2015 (UTC)

Help for VICE

My question about VICE above isn't getting any replies. It's possible no one here knows. So where could I find a forum I could ask for more help? JIP | Talk 20:08, 6 January 2015 (UTC)

You can try sending a polite email to the developers' mailing list, which can be found on their webpage: [email protected]...

On that page, they have additional instructions to help you file a bug-report, and how to ensure your mail gets through their filters.

Nimur (talk) 21:26, 6 January 2015 (UTC)

I'm not sure it's a bug. I might just not be understanding how VICE works. Can I still file a report? JIP | Talk 21:33, 6 January 2015 (UTC)

Yes. If it's not a bug, the developers will be happy to promptly close it! You can also ask them via email first. Nimur (talk) 23:06, 6 January 2015 (UTC)

Do I have to be on the VICE mailing list myself to receive replies or will they reply to my own e-mail address as well? JIP | Talk 20:35, 7 January 2015 (UTC)

You could try at StackExchange, or either of these emulator fora [8] [9]. There seems to be a lot of focus on NES era consoles and MAME, but you might still have better odds than here. SemanticMantis (talk) 22:41, 6 January 2015 (UTC)

Alarm clock

Does Windows (specifically, Windows 8) have any sort of alarm clock in it somewhere? Let's say that I am working on my computer. I want the computer to "beep" in an hour to remind me that I have to do something at that time. Is there anything in Windows that can do such a thing? If possible, I would prefer something that is already there, in the Windows operating system, as opposed to something that I have to download. Thanks. Joseph A. Spadaro (talk) 22:52, 6 January 2015 (UTC)

If you want an alarm at a particular time of day, and don't mind it popping up a message box instead of ringing, you can use Task Scheduler, as described here for example. If you want a timer that goes off 60 minutes after you set it, the only way I know to do it is to calculate the time yourself and add a one-time task at that time. You can automate it with the command-line schtasks utility; the command looks like

   schtasks /create /tn CommandLineMessage /f /sc once /st 23:45 /tr "msg * MESSAGE"

where 23:45 is the time it should alert you in 24-hour syntax and MESSAGE is the alert message. -- BenRG (talk) 06:05, 7 January 2015 (UTC)

Thanks. I will look into that. I'd really prefer an audio alarm, rather than a visual. But, I will see how this suggestion works. Thanks. Joseph A. Spadaro (talk) 23:32, 7 January 2015 (UTC)

One way to make an audio alarm might be to use Task Scheduler to start Media Player (or your preferred player) with an appropriate sound file. 175.45.116.61 (talk) 23:48, 7 January 2015 (UTC)

ping 127.0.0.1 -n 3600 & C:\Windows\Media\Notify.wav

— Preceding unsigned comment added by 82.44.45.127 (talk • contribs)

sleep 3600 would be better, but yeah, that's an easier solution if you don't mind leaving the console window open for the full hour. -- BenRG (talk) 00:22, 8 January 2015 (UTC)

computer theory

discuss 3 application of information and communication technology in education41.219.82.210 (talk) 15:01, 7 January 2015 (UTC)

Welcome to the Wikipedia Reference Desk. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. --Tagishsimon (talk) 15:13, 7 January 2015 (UTC)

While we're not allowed to do your homework for you, we can suggest some of our articles for you to read: I would think that Computers in the classroom and Distance education would be good starting points. When you're using Wikipedia to help you write academic reports, it's strongly recommended that (a) you don't just cut and paste from the article because your teacher will undoubtedly check for that and won't be happy if you do it...and (b) Use the references at the bottom of each article - they are far better places to get quotes and references that you can cite in your own writing. SteveBaker (talk) 15:45, 7 January 2015 (UTC)

Other general recommended reading would be educational technology. Recently, the MOOC has been much discussed. There's also correspondence courses, which used the the older technology of postal mail ("correspondence course" is now a redirect to "distance education" but I linked to the historical section on the practice in early universities). As a teacher, the technologies I use the most are email, chalk boards, pencil and notebook. Two technologies that were very standard for a long time but now seldom used - overhead projector and mimeograph. SemanticMantis (talk) 16:23, 7 January 2015 (UTC)

Materials, money, and technical expertise required to start a website from scratch?

Although I am aware of the free webhosting services and make-your-own-web-server tutorials, I am wondering what would be required to start a website from scratch. By "from scratch", I mean developing your own hardware for the web server or creating your own web server software, coding your own website, and developing your own registrar to host a domain name? How much money would a person have to invest in order to start and maintain a website? What technical expertise would such a task require? 71.79.234.132 (talk) 16:37, 7 January 2015 (UTC)

Do you really mean developing your own hardware and creating your own web server software? That seems as hundreds of millions and years developing it. --Noopolo (talk) 18:20, 7 January 2015 (UTC)

You are being very general. So, I could tell you that it will take you about a lifetime to develop you own hardware beginning with learning what electrons are, then going to understanding current flow, then learning how basic electronic components work, then learning digital logic, then building logic circuits, and then going into a completely different field of learning the basics of semiconductor chemistry and learning how to construct NPN or PNP layers on a wafer... However, I expect that you are asking about purchasing computer parts and building a computer to use a webserver. That is very easy. You need a network connection, a storage device, a processor, a motherboard, and a power supply. It would be nice to have some sort of interface, such as a monitor and keyboard. Then, as far as the software goes, you could spend another lifetime learning how to do socket programming and then learning why you keep getting buffer overrun attacks. Alternately, you could just install Apache. Now, coding a website is very easy. Learn HTML (it takes about 10 minutes for a normal person to learn that anything between < and > is an HTML tag and another 10 minutes to learn the 4 or 5 most commonly used HTML tags). Now, you can make a web page. You want to create a registrar? How much money do you have? It is very very very expensive to create a real registrar. You can make a fake one that only you use. It can be as easy as faking a lot of entries in your /etc/hosts file. But, if you want to make a real one, you need to get accredited with ICANN. Then, you have to get contracts with other registrars to work with them - and they won't want to work with you. You are better off trying to start your own bank than trying to start a registrar. Registering a domain name is much easier. Go to a registrar (any registrar) and see if the domain name is available. If it is, register it. Finally - the technical expertise. It is low - very low - if you are simply trying to get a web page online on your own server. Get a computer (any computer with a network connection). Install Linux and Apache on it (there are literally thousands of howto pages, books, videos, pictographs, etc... available). Make a web page. Plug it into the network. Register a domain name. Now the hard part that you skipped over: Get a domain name service that points your domain name to the IP address of your webserver. Then, you are done. — Preceding unsigned comment added by 209.149.113.90 (talk) 19:10, 7 January 2015 (UTC)

The problem here is what is meant by "from scratch"? If you mean from the level of piles of rocks and trees, so you have to refine the silicon from which to make your circuits...then clearly you'd need an insane amount of time. If you also assume that you have to first discover electricity and invent the concept of a computer - then it's even longer! If you mean from a bare-bones PC, you'd need to at least rewrite Apache (or some kind of subset of it) and a large chunk of the operating system. If you have the right skills and knowledge, then you could probably make a web site with minimal functionality it in under a year...maybe just a few months. But if you mean from a functional Linux machine with Apache already on it...then much, much less time. Really, it's not possible to come up with any kind of meaningful answer unless you first define your terms. SteveBaker (talk) 21:13, 7 January 2015 (UTC)

From natural resources: rocks and trees. Explain the process. Or if it's too long, please help me find resources. I really need to be more tech-savvy, which involves where the resources come from to be made into silicon chips and computers. 71.79.234.132 (talk) 21:43, 7 January 2015 (UTC)

If you wish to make a website from scratch, you must first invent the universe. Vespine (talk) 21:47, 7 January 2015 (UTC)

The reason I gave a flippant answer is your question seems very frivolous. You KNOW what you are trying to find out, do you want us to google it for you? There's nothing stopping you doing it yourself: Start by searching "how are silicon chips made", the move onto "how was the transistor invented", perhaps "where does silicon come from"? history of computing is a good article, as is history of computing hardware and history of the internet, then basically be prepared to spend the rest of your life looking up random articles, clicking through links you find interesting and learning about stuff you've never dreamed of. There are no shortcuts. Welcome to the club. Vespine (talk) 21:53, 7 January 2015 (UTC)

Really, 71.79.234.132, the previous commentators are right. Your question is too vague. What do you mean by "from scratch"? From basic elemental materials, from basic electronic components, or from a set of ready-bought computer components and an operating system? Please specify in more detail. JIP | Talk 21:58, 7 January 2015 (UTC)

There is too much to learn. It would take lifetimes to learn it all; it would take years just to paraphrase it.

Perhaps the original poster should read the famous essay, I, Pencil (1958), in which economist Leonard Read remarks that millions of humans are involved in the creation of even our simplest artifacts. Perhaps more accessible is the somewhat sensationalized 2010 TED Talk, When Ideas Have Sex, in which author Matt Ridley puts forward the premise that nobody on Earth knows how to build a computer mouse. For comparison, he shows a stone adze made by humans from the paleolithic era, and a similarly-sized computer mouse made in 2010. Many ancient humans knew how to build stone tools - each individual knew everything necessary to harness natural resources and produce state-of-the-art technology. Today, this is not true: instead, our collective - our society - knows how to build a computer mouse; but unlike our paleolithic predecessors, our technological knowledge does not reside in any individual. This is specialization of labor.

These ideas paraphrase what you will read in any good book on the history of technology or anthropology. The present level of knowledge that our species has accumulated is too large for you, as an individual, to know all of it.

Our best and brightest students in modern schools begin diligent study at the age of 3 or 4. Students who wish to specialize in technological applications might not finish study until they are 22 or 25 or 30 years old. In other words, if you diligently study prior human accomplishments, it will take over twenty years of intense and difficult education, and you might just barely catch up to, say, elementary calculus - where our mathematicians were making new discoveries four hundred years ago. Even if we have an open mind and consider alternatives to conventional Western education, we have a meta-problem: we still do not know a method that is more efficient at transferring knowledge per unit time. While conventional education may have some flaws and inefficiencies, the alternatives tend to be categorically slower: you will not find any Montessori schools that crank out more practicing engineers per unit of time. In other words, we do not yet have technology to holistically educate our next generations about our existing technology. Instead, our system produces specialized students with areas of expertise, and the sum-total knowledge is only retained, piecemeal, among many different individuals.

Extrapolating forward, it becomes clear that if our society keeps advancing our knowledge of science and technology, we will eventually reach a time when it takes so many years to learn prerequisites that the average human will die before they can advance the species. Science fiction author Isaac Asimov explored this in his story Profession (1957), in which a super-advanced human society must figure out how to efficiently educate its citizens: first, students are selected for their psychological profile, and then a machine accelerates the transfer of knowledge from a computer-tape into their brain, because there is so much they need to learn. This trope has been emulated by lesser authors and screenwriters for decades to follow. I'm fairly certain that when we do invent such a device, it's going to look a lot like a free, free digital computer-based encyclopedia.

Nimur (talk) 14:42, 8 January 2015 (UTC)

So, what happens when there is a catastrophic global war that destroys most of human knowledge stored in computers and electronic databases as well as kills many people of specialized expertise? Will that mean humans have to rebuild everything all over again? 71.79.234.132 (talk) 16:00, 8 January 2015 (UTC)

Possibly. It depends on how complete the loss of knowledge is. Consider this: in much of the developing world, and even in some unfortunate parts of the developed world, basic facts of science - like the germ theory of disease- are not widely understood. It is not actually impossible to learn these facts; these facts are freely available and have not been "lost" to catastrophe; but nonetheless, there exist entire societies exist in which the critical-mass of educated people is insufficient to shape national policy. I worry more about the climate of social behaviors that hinder progress, which are more dangerous than any "catastrophe-event" like an immense global war or a natural disaster. As long as humans are free to improve themselves, I am confident we will adapt whatever remaining natural resources we need to improve our condition, natural and manmade calamities notwithstanding. My optimism is not unique: if you'd like to spend an hour hearing great thinkers and innovators and policy-makers of our modern technological society discuss this topic, here is Ted Koppel moderating a 2006 "roundtable discussion": Seeing Beyond a World of Perpetual Threats. We're rebuilding our world every day. Nimur (talk) 16:33, 8 January 2015 (UTC)

January 8

Distance to route

When using Google Maps or Mapquest, I've often wanted to ask "What's the closest restaurant/gas station to the route I've entered". Is there a way to do this, as opposed to finding the closest places to one point ? StuRat (talk) 02:25, 8 January 2015 (UTC)

Addendum: The road distance would be ideal, but straight line distance is better than nothing. StuRat (talk) 17:21, 8 January 2015 (UTC)

'D' on my Oyster card

I have a London Oyster card. On the back, it gives the usual blurb about terms and conditions. Underneath, it says 'Mayor of London' and left of that, the letter 'D'. What does the 'D' stand for? — Preceding unsigned comment added by 36.225.127.145 (talk) 05:26, 8 January 2015 (UTC)

As seen here, I presume.  (No idea why 'D' seems to be part of the logo for 'Mayor of London')  ~:71.20.250.51 (talk) 06:09, 8 January 2015 (UTC)

Is it not shorthand for Domine, dirige nos, the motto of the City Corporation? (It's also plausible that a group of incorporated Yankees put the D there (for dissent) and expertly filed legal proceedings banning its removal):

“ It reminded me of something I had read in my youth about the ingenious way in which the aldermen of London raised the money that built the Mansion House. A person who had not taken the Sacrament according to the Anglican rite could not stand as a candidate for sheriff of London. Thus Dissenters were ineligible; they could not run if asked, they could not serve if elected. The aldermen, who without any question were Yankees in disguise, hit upon this neat device: they passed a by-law imposing a fine of L400 upon any one who should refuse to be a candidate for sheriff, and a fine of L600 upon any person who, after being elected sheriff, refused to serve. Then they went to work and elected a lot of Dissenters, one after another, and kept it up until they had collected L15,000 in fines; and there stands the stately Mansion House to this day, to keep the blushing citizen in mind of a long past and lamented day when a band of Yankees slipped into London and played games of the sort that has given their race a unique and shady reputation among all truly good and holy peoples that be in the earth. ”

—Chapter 25, A Competitive Examination

Nimur (talk) 14:47, 8 January 2015 (UTC)

No, the City of London is not London, and the Mayor of London is not the Lord Mayor of London. Oyster Cards, as with the rest of Transport for London, have nothing to do with the City of London. -- Finlay McWalterᚠTalk 15:27, 8 January 2015 (UTC)

The D does not appear in any other use of the Mayor of London logo that I've seen; I don't believe it's associated with that. It doesn't appear on all Oyster cards (it's not on the rather old one I have, nor on most of the ones Google Images finds). I can't find mention of any other letters in its place, and I can't find any indication that there is an obvious version scheme in the cards' printing (there is a per-card serial number). -- Finlay McWalterᚠTalk 15:35, 8 January 2015 (UTC)

Do you have a disabled person's card? A Complete staff guide to ticketing on London's Buses (PDF) lists several codes that are printed on the card in a blue box, such as "C" for child, "E" for elderly, "D" for disabled, "VCTS" for veterans, etc. 88.112.50.121 (talk) 17:44, 8 January 2015 (UTC)

No, it's just a standard Oyster card that I ordered online and had delivered to me, as I didn't live in London at the time. Could it mean 'delivery', or perhaps something to do with the deposit?36.225.127.145 (talk) 00:31, 9 January 2015 (UTC)

But don't disabled persons get a Freedom Pass rather than a special Oyster Card? That "D" sort of resembles the format for the other discount cards, but they put the special designation on the front where the name and photo are. -- Finlay McWalterᚠTalk 18:06, 8 January 2015 (UTC)

This page says "The DESfire Oyster card can be identified by the letter ‘D’ in white on a black box on the back of the card." The background in 71.20.250.51's image appears to be blue, but maybe there's a connection anyway. -- BenRG (talk) 06:08, 9 January 2015 (UTC)

MS Word 2010 Navigation pane

Does anyone know how to keep the MS Word’s navigation panes headings unopened? Every time I open MS Word it tends to open all the headings showing the complete hierarchy. I need to keep it unopened. -- (Russell.mo (talk) 17:12, 8 January 2015 (UTC))

Never mind. -- (Russell.mo (talk) 07:13, 9 January 2015 (UTC))

Resolved

Windows server family

Hey guys,
I got few questions and I'll be grateful if you answer for me:
1. If I install Windows Home Server, Must I make it a DHCP server? Or may I choose which computer be connected to it if any?
2.If I install on a different computer this Windows version, must it be always open? Or can I close it sometimes? What will happen if I shall close it sometimes?
3.Does this version have "low-energy" mode, on-which the computer hibernates, but still can awake independently, or at least in scheduled events?
4. Let's assume that I can have both for free, both, I mean Windows Home Server, and Windows Server 2008 R2. Is there any reason to pick Windows Home Server. Does it require crazy requirements for a home-scale network?
Thanks.Exx8 (talk) 17:36, 8 January 2015 (UTC)

Flickr duplicate pictures

Is there a way through Flickr if one can tell if one has uploaded duplicate pictures? Like for example a listing of JUST the duplicates. I want to be able to somehow find the duplicates quickly and then delete the duplicate ones, which will leave just the one particular picture in my uploads. How can you then can you delete the duplicate Flickr pictures?--Christie the puppy lover (talk) 19:38, 8 January 2015 (UTC)

New type of ad strategy

This was interesting. A screen shot, even if I could remember how, wouldn't have worked. You would have to see a video to understand, and I didn't know how to do that.

After a few seconds, the old ad floated away to reveal the new ad, as if it was on top of a stack of papers and the wind was blowing. Or as if an unseen hand picked it up and put it aside.

Anyone know the name of the technique?— Vchimpanzee • talk • contributions • 20:01, 8 January 2015 (UTC)

Could it have been a Flash ad? -- 143.85.169.18 (talk) 22:57, 8 January 2015 (UTC)

I didn't see it today. And I'm not sure how to ask anyone. I've seen many ads that caused the Adobe Flash Player to crash, so it is used somewhere.— Vchimpanzee • talk • contributions • 17:52, 9 January 2015 (UTC)

January 9

Multiple CPU cores vs one bigger CPU?

Is it better to have multiple CPU cores instead of just having all those transistors together in one big processor? Or is the only way to have a bigger processor by having more than 64 bits? --78.148.105.13 (talk) 01:21, 9 January 2015 (UTC)

Personally I think more cores is better, allowing you to expand the capabilities of a CPU more economically. StuRat (talk) 04:12, 9 January 2015 (UTC)

To make a computer faster, you can either put in more processors, or make the processors faster. It is sometimes possible to make a processor faster by making more sophisticated versions of units such as the adder. Also, the processor can be made faster by adding more transistors to allow for speculative execution. A method related to speculative execution is the pipeline. But at some point the designers run out of worthwhile things to do with more transistors, and the remaining alternative is more processors. Jc3s5h (talk) 04:42, 9 January 2015 (UTC)

More than 64 bits wouldn't necessarily help. '64 bits' refers to the word size of the platform, and it influences a few important things, such as how wide registers are (crudely, how big a number you can operate on) and the width of the address bus (and therefore how much physical memory the system can have). The reason 64 bits is a big improvement over 32 is that a 32 bit system can't have more than 4GB of physical RAM (and in practice more like 3.5GB) while a 64 bit system can have the square of that - about 16,000,000 TB. 3.5GB was becoming a limit; 16,000,000 TB is not yet.

The main factor in improved CPU performance for many years was increasing clock speeds (though there were other improvements, such as increased amounts of cache, pipelining, branch prediction, speculative execution etc). Once clocks hit about 3GHz, we ran out of ideas for how to increase it further. The thing limiting it is, for the most part, heat. CPUs are built of field effect transistors and when FETs switch, a small amount of charge has to pass into or out of the gate. This movement of a charge is an electric current and the material it moves through has a resistance, and so heat is dissipated (the amount being given by P=i*i*R). The amounts involved are tiny, but when you scale that up to several billion transistors switching several billion times per second, you get a significant amount of heat. The more times they switch per second, the more heat you get.

To reduce the heat, you have reduce either the amount of current or the amount of resistance, and you get more mileage out of reducing current (because of the i*i term above). The main way of doing this is to reduce the size of the transistor (as a bonus, reducing the size of everything also reduces resistance, since the charge has to travel less distance). This is still happening, but much more slowly than it had.

Since we can't figure out how to make a core do things faster, the only option left is to do more than one thing at once (ie multiple cores, though note the simplification here that some CPUs already had the ability to execute multiple instructions at once).

Which is better? The answer is, of course, that it depends on what you're doing. For most consumer use cases, two cores running at 2GHz will give you better performance than one running at 3GHz. But if you're doing certain types of simulation or software development, then maybe the 3GHz single core will be better. The ideal answer is, of course, both, and the even-better-than-that answer is to spend your money on an SSD instead, if you haven't already. GoldenRing (talk) 04:55, 9 January 2015 (UTC)

On that 16,000,000 TB limit, even if we figure disk space will double every year, it would still take over 20 years to hit that limit, so 64 bits should be good for a long time. And for storing numbers, 64 bits is plenty, too, but we could always store numbers in two registers, if we need bigger numbers/numbers with more precision. StuRat (talk) 05:52, 9 January 2015 (UTC)

Trustworthy sources of Windows builds of open source software?

Some of the open source software I use is hosted at Sourceforge. I've stopped downloading Windows installers from SF since reports came out in 2013 that installers hosted there were bundled with extra/unwanted software. Are there trustworthy alternative sites for Windows builds of open source software, ones that don't bundle extra stuff in the installers?

Are there ways to confirm that no unwanted extras are bundled in an installer? --134.242.92.2 (talk) 16:22, 9 January 2015 (UTC)

Do you routinely run your virus checker program against those installers? ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:28, 9 January 2015 (UTC)

I experimented with 2 installers from SF. Both times the scanner didn't detect anything. It could be that there was nothing worth reporting, but it could also be that the scanner was not doing a good job. --134.242.92.2 (talk) 16:41, 9 January 2015 (UTC)

I've downloaded stuff from Sourceforge without problems, but you do have to read very carefully and decline the "extras". It's annoying that a formerly safe site is now getting a bad reputation. Dbfirs 16:57, 9 January 2015 (UTC)

Are you talking about SourceForge's DevShare program? If so, as far as I can tell, any project that uses it has a separate "direct download" link below the main download button that will take you to a clean installer. In the case of sites like download.com that add crap to other people's installers without their consent, I would recommend going to the official web site to get a clean installer. But that's unlikely to work in this case because DevShare is only enabled if the developer requests it, and revenue from it goes to the developer. Since the developer likes sideloading, you're likely to get a different sideloading installer on the official site, one that hasn't been vetted by SourceForge, and likely without the option of a clean installer. And if you go to some random download site offering the software, you'll likely get an installer with nastier bundled software, or at best the official installer. So SourceForge is probably still the safest place to download these programs in most cases, as long as you click the correct link. (Also, DevShare only affects a tiny fraction of the packages on SourceForge.)

If you want to install some software but don't entirely trust the installer, Sandboxie is useful. You can run the installer inside a sandbox, check that it didn't secretly install anything unwanted, and then either drag the main application folder out of the sandbox (which may or may not work) or else delete the sandbox and install the software for real. -- BenRG (talk) 19:29, 9 January 2015 (UTC)

January 10

Can't re-enable an app

Dear Wikipedians:

I use Samsung Galaxy Tab 3 and recently I have disabled a built-in app called T-memo version 2.0

When I tried to re-enable that app today I found that I cannot do it. The button that was supposed to say "Enable" still says "Disable" and is greyed out. So now the app is stuck in the "Disabled" section of apps. See screenshot below:

I was wondering if any of you have had similar experience and know how to fix it?

Thanks for all your help.

L33th4x0r (talk) 02:59, 10 January 2015 (UTC)