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May 14

Default Firefox fonts

Something happened and my fonts got changed, the default to Times New Roman 16. I've changed the size to 12, which looks approximately right, but the letters in an edit's comment field and the subject/headline of this question are tiny. How can I reset it all to the standard defaults? Clarityfiend (talk) 03:28, 14 May 2015 (UTC)[reply]

Resolved

Is dosbox a emulator or a virtual machine?

Is dosbox a emulator or a virtual machine?201.79.82.81 (talk) 12:54, 14 May 2015 (UTC)[reply]

DOSBox is an emulator. An emulator is a kind of virtual machine, which (despite the similar names) is quite different from hardware virtualization. -- Finlay McWalterᚠTalk 13:05, 14 May 2015 (UTC)[reply]

Urgh. On reading the virtual machine article, it seems people are still using "virtual machine" both to mean a software-invented pretend computer (like DOSBox or the Java Virtual Machine) and the hardware-invented pretend sub-instance of a real computer (like VirtualBox or VMWare). -- Finlay McWalterᚠTalk 13:30, 14 May 2015 (UTC)[reply]

DOSBox performs software simulation of individual i386 CPU instructions, so it is a full CPU simulator as well as a running instance of an operating system. The brief status summary hints at some implementation details: for example, if you dared to build and run DOSBox on a PowerPC platform, your simulated x86 processor's math functions would not be bit-exact. (Rather, the simulated 387 Floating Point extensions to the x86 processor would be implemented using libc and libm and would execute as native floating point instructions in the real machine's architecture).This means that DOSBox is not a pure virtualization of the CPU. Such bit-exact machine simulations are very rare, because they are so dramatically low-performance; but they do exist. For example, people who design CPUs wish to simulate the CPU at the gate-level and instruction level: this would be design verification (a standard subtask of EDA in the normal workflow to design digital logic and build it on silicon). It may be possible to emulate a full operating system and application software on top of such a virtual machine, if you're willing to wait a few days for the system to boot. Nimur (talk) 13:45, 14 May 2015 (UTC)[reply]

A long time ago I worked at a company which designed its own CPUs. The chip designers ran gate-level simulations of the whole device on clusters of workstation-grade machines. Thus simulated, it took a day or so just for the CPU to boot. It had hitherto not occurred to me that CPUs actually did anything in order to "boot"; I was wrong. -- Finlay McWalterᚠTalk 13:56, 14 May 2015 (UTC)[reply]

And then there is the system described at [ http://dmitry.gr/index.php?r=05.Projects&proj=07.%20Linux%20on%208bit ]: a system that emulates a 32-bit ARM CPU/MMU on an 8-bit ATMega microcontroller. It takes two hours to boot Linux ( https://www.youtube.com/watch?v=nm0POwEtiqE ) and about a minute to respond to a command. the designer calls it the "cheapest, slowest, simplest to hand assemble, lowest part count, and lowest-end Linux PC." --Guy Macon (talk) 14:15, 14 May 2015 (UTC)[reply]

Is the expression "Data product" ?

What does "data product" (Data_analysis#Data_product) actually mean? Is that different from an app or program (offline or online) running independently? Aren't all programs data products somehow? Besides that, why call it "product" which leads to confusion since it implies the result of processing, and not a program processing data and suggests that it's proprietary? --Llaanngg (talk) 17:39, 14 May 2015 (UTC)[reply]

You are apparently thinking that "product" in the business sense (something that may be offered for sale or trade). This term is using the mathematical "products" (the result of multiplying). It is correct that you are not really multiplying to data items to get a data product, but it is a similar concept. You are taking some data items and producing a new data item. The data product is the new data item (the product of the operation performed on the old data items). An example that I do a lot is BMI. Give me two data items (height and weight) and I can produce a new data item (BMI). As you can see, the app that I wrote to do this work is not the data product. The result of the app (and no - it isn't really an app. I don't work for Apple and I don't call everything I write an app) is the product. Further, the result of all processing is not a data product. If I count how many records meet a criteria, I get a number. But, that number isn't a data item that is of reasonable use for the data environment, so I don't feed it back into the data environment. So, it is not a data product. 209.149.114.204 (talk) 18:46, 14 May 2015 (UTC)[reply]

How can I strip the background music from an mp4 file?

I have an mp4 video of 3+ hours that I have to watch for educational purposes. The voice on it is OK, but it has a very repetitive background music. Just think tetris music, but worse, all 3+ hours long. Is there a way of eliminating the background music and keep the voice?--Llaanngg (talk) 17:42, 14 May 2015 (UTC)[reply]

This is sometimes known as "vocal removal" or "vocal isolation"- I can't find any specific WP articles, but it's a subclass of digital signal processing - here are some instructions on how to do it with Audacity [1]. This kind of thing can sometimes be done passably well with a "one-click" algorithm, but it requires some human art and skill to get it done right. SemanticMantis (talk) 17:56, 14 May 2015 (UTC)[reply]

It's much trickier to remove background music using the "noise reduction" facility in Audacity, but it's worth a try. If the background music is high pitched and the voice low pitch, then a simple filter might remove it, though you'll lose some sibilants. If you post a short sample of the mixture somewhere, then we could experiment, or you can download Audacity yourself. Dbfirs 20:20, 14 May 2015 (UTC)[reply]

→VLC media player --Hans Haase (有问题吗) 12:41, 16 May 2015 (UTC)[reply]

Image file becoming Fuzzy

Hello!

I have an image file containing alphabets that are very small, it becomes fuzzy when I ‘zoom in’, any workaround available?

Mr. Prophet (talk) 19:26, 14 May 2015 (UTC)[reply]

It would help if you posted the image file in question.--Aspro (talk) 19:33, 14 May 2015 (UTC)[reply]

Its an old image file from my HDD -- Mr. Prophet (talk) 21:53, 14 May 2015 (UTC)[reply]

Probably not without some decent effort, and even then, it might not be enough to allow you to read the text. See super resolution. If you got the image off the internet somewhere, there is a decent chance a higher image resolution version is available elsewhere. Try putting the image in to TinEye or Google's "search by image" to see if you can find other, better copies of the same image. This of course will not work if you took the photo :) P.s., this is one reason why WP and many other places prefer vector graphics over raster graphics for many purposes - the former never become blurry, no matter how far in you zoom. It is also possible that image tracing may help by converting your raster to a vector format, depending on your goal and the nature of the image - this is not usually used as a technique to get more sharpness out of images, but it can sometimes result in slightly more readable small text SemanticMantis (talk) 19:41, 14 May 2015 (UTC)[reply]

Everything of my google is in different language. Inkspace apparently supports 'image tracing', it sound similar to 'Adobe illustrator', the 'vector graphics' thing. I have illustrator, I opened the file went to 'Object' menu, fiddled with the 'Image Trace' feature's features after selecting the complete image, no luck... How would I convert a file from 'raster' to 'vector' using 'Adobe illustrator'?

There are a a bunch of converters however in the internet, which one would be the best, what I could keep for future use...?

Mr. Prophet (talk) 21:53, 14 May 2015 (UTC)[reply]

Here's instructions on how to "trace" a bitmap/raster and get a vector image in Inkscape [2]. Is your goal to be able to read things that you couldn't before, or to have it look better when you zoom in? This might help, but it might not, at least it is free and fairly easy. SemanticMantis (talk) 13:29, 15 May 2015 (UTC)[reply]

Read things I couldn't before. Hope it works... Thanks. -- Mr. Prophet (talk) 18:33, 15 May 2015 (UTC)[reply]

If they get fuzzy when you zoom in (as opposed to "jaggy"), that sounds like subpixel rendering or a related method. StuRat (talk) 04:29, 15 May 2015 (UTC)[reply]

I don't know what it is, the image looks fine in the ordinal shape, the words are very small, say 'font size' between 1 to 5, the writing becomes blurry when I zoom in... -- Mr. Prophet (talk) 06:10, 15 May 2015 (UTC)[reply]

The methods I refer to color each pixel differently. This method looks terribly fuzzy when you zoom in. StuRat (talk) 14:11, 15 May 2015 (UTC)[reply]

Lol. -- Mr. Prophet (talk) 18:33, 15 May 2015 (UTC)[reply]

See dpi and display resolution. For faster loading a webpage, use thumbnails, downsized versions with less pixels of the pictures. For a detail view, you need the full resolution. If you don't have, use inkscape, load the picture and draw a vectorbased layer over the original bitmap. I can be done automatically, press Ctrl+Shift+B, but may have not the best results. When using it as font, better use a font editor, but do a search first to save huge unneccessary work. --Hans Haase (有问题吗) 07:21, 16 May 2015 (UTC)[reply]

Guys, what shall I download? I'm on 32-bit, the '.msi' is 80Mb, '.exe' is 40Mb. I've read through them, what confused me was the information about 'they could only be a type of file which will insist/download other files from the internet, meaning I have to have a full internet connection... This is the first time, in my life time, probably, I actually saw two or more options in one place for one software. The 'installer (exe)' file is preferable as I'm on 'payg: Kbs' as long as it doesn't tell me to download more files... -- Mr. Prophet (talk) 18:42, 16 May 2015 (UTC)[reply]

I'm still using the old 0.48 version, 32 bit only. The installer will install the whole program on a computer. The portable app is - I guess, the programm and ressource files in an archive to run from a USB flash memory stick, portable harddrive or similar file system ressource. If the internet connection is not the problem, download a stable 32 bit version. An installer or download differs from real memory (RAM) usage. --Hans Haase (有问题吗) 10:15, 17 May 2015 (UTC)[reply]

I can download adult video clips after the end of the month. Thanks!

-- Mr. Prophet (talk) 19:40, 17 May 2015 (UTC)[reply]

It is weird that there are two installers. They use different installation systems (the exe is NSIS, the msi is Microsoft Installer) but seem to install the same stuff. Neither one needs Internet access. I don't know why the msi file is twice as large. Use the exe. -- BenRG (talk) 05:35, 18 May 2015 (UTC)[reply]

I'll be downloading it tonight hopefully. Thank you. Btw, I know what you mean...first time for me too. -- Mr. Prophet (talk) 06:05, 18 May 2015 (UTC)[reply]

Thanks friends Thank you for the assurance too, I needed it... Take care. -- Mr. Prophet (talk) 05:55, 18 May 2015 (UTC)[reply]

File doesn't load up, installed and waited... -- Mr. Prophet (talk) 10:54, 18 May 2015 (UTC)[reply]

May 15

Technical side of WP:B

Over the past few months, I've been introduced to basic scripting for the first time, which in this case is simple keyboard and mouse macros — I knew they existed, but I never had a clue how they worked, how to write them, how to understand the code, etc. Having recently filed a simple bot request, I'm left wondering — if your bot's fulfilling a simple task (which in this case encases a date with a template, and if it has a specific category, it removes it), is it reasonable to program your bot by using a keyboard-and-mouse macro, or are there typically other, more-substantial types of programming that work better? I mean, I could easily write a Macro Express macro to fulfill the bot task in question (but I don't have access to the program except on a work computer, so there's no point in trying), but I don't have any choice, because I'm not familiar with normal programming languages. If you could write in Java, C++, Python, Pearl, and various other languages, would you typically find a macro the simplest way of programming a simple find-and-replace bot, or would one or more of the more advanced languages generally be simpler? Nyttend (talk) 00:57, 15 May 2015 (UTC)[reply]

In programming, there is usually about a hundred (at least) ways to do something. Idiots argue about the best way. Whatever gets it done is fine. For text manipulation, I would use Perl or sed. That is their strength. But, I could use PHP or Java or C++ or Ruby or Haskell or Ada or... I actually have trouble remembering all the llanguages I've had to use over the years. 75.139.70.50 (talk) 03:27, 15 May 2015 (UTC)[reply]

Well, some methods are better than others, but it is true that perfectionism in programming can be problematic. That is, you can spend more time, effort, and money trying to find the best solution than it's worth. A cost/benefit analysis figures in here. StuRat (talk) 04:25, 15 May 2015 (UTC)[reply]

May 16

Dictionary and or Thesaurus

I'm/I've been searching for a Thesaurus as well as Dictionary (combined) which 'only' retrieves the formal words/words list for any rubbish known typed word. Are there such software available which will only provide 'formal' word(s)? -- Mr. Prophet (talk) 18:47, 16 May 2015 (UTC)[reply]

I'm having a hard time understanding your request. What is a "formal word"? Do you mean to say "formal grammar"? Are you seeking a conventional dictionary of natural human language, or do you mean a dictionary (data structure) to look up words in the sense of parsing a computing language? Perhaps if you rephrase your request, you will get a better answer. Nimur (talk) 15:52, 17 May 2015 (UTC)[reply]

Do you mean where you can type in a misspelled word and find the correct spelling and definition ? Google will do this, if you type in "define" followed by a space and your misspelling: [3]. StuRat (talk) 18:01, 17 May 2015 (UTC)[reply]

I have a 'Pocket Oxford Dictionary 1994' (3.13Mb) and 'Cambridge Advanced Learners Dictionary - 3rd Edition 2008' (528Mb).

Cambridge Advanced Learners Dictionary - 3rd Edition 2008 (528Mb):-

When I click on the 'Advanced Search' button it provides an option in which I can customise my search. One feature it has called 'Usage' with a 'drop down list', and you can select 'abbreviation, approving, child word, disapproving, figurative, formal, humorous, internet, informal, legal, literary, not standard, offensive, old fashioned, old use (historical), polite, saying, slang, speacialised, trade mark, written abbreviation', whatever you select, it displays all the selected item's words available in the Dictionary, after clicking the 'Find' button. 'Pocket Oxford Dictionary 1994' does not offer this facility and I'm not aware of whether it displays any sign whatsoever. Problem with 'Cambridge Advanced Learners Dictionary - 3rd Edition 2008' is, it does not have/provide the facility to type a word in order to retrieve all the relative words, like 'thesaurus', of any I've embolden above, so, I guess I'm looking for something that works like 'thesaurus' which displays all the relative words of my chosen word (which will be inserted in the field), the embolden words only...

A 'thesaurus' and 'dictionary' together would be beneficial. A free software would be great; if there isn't then just tell me the name (if there is), I'll search for it in the market and see if I find it... However, if there is a website, let me know.

Mr. Prophet (talk) 20:36, 17 May 2015 (UTC)[reply]

May 17

What type of HTML uses indenting instead of closing tags?

I once saw a version of HTML that relied on whitespace instead of closing tags to end scope, sort of similar to CoffeeScript. Does anyone know the name of this variant of HTML? A Quest For Knowledge (talk) 21:39, 17 May 2015 (UTC)[reply]

Some HTML tags don't need to be closed, like the br tag used between lines 1 and 2, without the closing tag, and between 2 and 3, with the closing tag:

1
2

3

StuRat (talk) 21:48, 17 May 2015 (UTC)[reply]

What I am saying is that in most languages, white space is not significant in how code is written. However, there are some languages where white space matters. For example, in JavaScript, white space doesn't matter. You could code this:

if (true) {
  doSomething();
} else {
  doSomethingElse();
}

...which is semantically identical to this...

if (true) {
doSomething();
} else {
doSomethingElse();
}

...which is semantically identical to this...

   if (true) {
doSomething();
   } else {
doSomethingElse();
   }

But the equivalent CoffeeScript has no scope terminators such as closing brackets. Instead, it relies on indentation to determine scope. So, this is how you would write the identical code in CoffeeScript:

if true
  doSomething()
else
  doSomethingElse()

...whereas this would mean something completely different (I'm not sure that this code would even transcompile) ...

if true
doSomething()
else
doSomethingElse()

I once saw a version of HTML that worked the same way. Instead of closing tags, it relied on white space to determine scope. So, instead of this...

<html>
  <head>
    <title>This is a title</title>
  </head>
  <body>
    Hello world!
  </body>
</html>

...it looked something like this...

<html>
  <head>
    <title>This is a title
  <body>
     Hello world!

A Quest For Knowledge (talk) 22:06, 17 May 2015 (UTC)[reply]

Have you any more context? For instance, Hamlet templates[4] can look like this. They aren't really a 'version' of HTML, but nor - I think - was whatever you remember. 82.13.241.56 (talk) 23:16, 17 May 2015 (UTC)[reply]

I once used a language for a CNC punch machine that didn't allow empty spaces at the ends of lines. It would give me very strange errors when it happened and it took me at least an hour to find the problem the first time it happened since a space isn't visible. I eventually found it by mistake when I happened to put the cursor at the end of the line and noticed the space. You can bet your life that I never forgot about that error! But this was not HTML. Dismas|^(talk) 23:44, 17 May 2015 (UTC)[reply]

Also see: Whitespace (programming language)... --Guy Macon (talk)

May 18

Javascript basics question (I just want to know if I understood right)

Does dot (.) in Javascript equals GET? thanks, Ben-Yeudith (talk) 03:44, 18 May 2015 (UTC)[reply]

No. The dot is a property-accessor. A dot connects an object with a property, which can be another object or a method (function). For instance, to get the value of a property through its get() method: var language = object.get('lang');. -- [[User:Edokter]] {{talk}} 09:30, 18 May 2015 (UTC)[reply]

Websites that disable unregistered users from viewing - how does that work?

Quora, Tumblr, and Experience Project seem to deny browsing accessibility to unregistered users. In other words, one needs to register an account, sometimes with personally identifiable information, in order to browse the network. Alternatively, one can view specific webpages, if one has the uniform resource locator. If an user is interested in more related questions on Quora, then that user is advised to create an account with his or her real name. On a technical level, how does that ability to deny browsing to unregistered users work? Is there a formal or technical name for this? Although I have learned basic HTML and CSS and Javascript, I find that I have a lot to learn in the world of computer programming. 140.254.136.178 (talk) 12:59, 18 May 2015 (UTC)[reply]

A registered user will typically log in, after which the server will store a HTTP cookie in their browser (which their browser sends back to the site every time it requests a page on that site). By checking to see if a visitor supplies a valid cookie, the site can limit what content is visible and to whom. They could chose to send anyone without the cookie to a login page, thus making the whole site inaccessible to unregistered visitors. But it the sites you describe want to hook in new visitors (especially people coming from search engines like Google and discussion sites like Reddit). So they've decided to give people arriving at the site, even without the cookie, access to just that page - but they still want to encourage people to register, so they don't want those visitors moving to subsequent pages on the site without registering or logging in. They can see if a browser was referred to the site externally by checking the HTTP referer field in the request the browser sends; people coming e.g. from Google will have a Google URL in that field; people moving around inside Quora will send a Quora URL. So they probably have logic that reads something like:

    if (request.cookie == none) and (request.referer.domain != "quora.com"):
        show_page (request.url)
    else:
        show_page (login_or_register_screen)

-- Finlay McWalterᚠTalk 13:17, 18 May 2015 (UTC)[reply]

Since the server is really another computer, how does this computer/server thing recognize incoming data? Are data transmitted through wires? What about wireless Internet? Does a person have to set up an unmanned satellite into space in order to transmit its own messages from its own servers to other people's computers? 140.254.136.178 (talk) 13:32, 18 May 2015 (UTC)[reply]

That's right. But remember you'll have to connect your satellite with cables to every client machine (including laptops, tablets, smartphones etc.) :-P --CiaPan (talk) 14:18, 18 May 2015 (UTC)[reply]

Randomatic - early 70s computer

In The Anderson Tapes (a 1971 film), the police use a computer called a "Randomatic" to call up details of suspects. A series of buttons are pressed, some clicking and whirring occurs, and a card with the details on is output. Was this a real machine? Were they police-specific or used for other purposes? Any other information gratefully received. DuncanHill (talk) 17:20, 18 May 2015 (UTC)[reply]

Here's a picture of it (from the movie). I think it was a real device, made by Randomatic Data Systems, Inc. (not affiliated with Sperry Rand) and covered by some of these patents. -- BenRG (talk) 17:58, 18 May 2015 (UTC)[reply]

[EC] If I remember correctly, the RANDOMATIC was being talked about (mostly to potential invesors) in the film industry in the early 70s, but it wasn't shown until the 1976 Los Angeles SMPTE convention. It was a system developed by The Intercraft Corporation in NYC and Randomatic Data Systems in Trenton. It was a card selector "computer" where bars were raised in selector trays to lift or not lift cards according to holes/notches in the cards. Instead of the usual editor's log book used in producing a film, the cards would contain info on locations. actors, camera, etc. so you can ask "show me all scenes with John Smith on soundstage three using camera B". Card lifting systems predated the RANDOMATIC, so perhaps this was an early prototype or maybe the special effects people just took the idea and made something that resembled it for the film. I will see if the film is available on netflix and watch it. I will be able to tell you more once I see the scenes in question. --Guy Macon (talk) 18:14, 18 May 2015 (UTC)[reply]

And note that they are using "random" here to mean "you can select the cards in any random order you decide you want to access them", as opposed to in sequential order. This is the same way it is used in the term RAM, which is unfortunate, in both cases, because it seems to imply that you will ask for a card or bit of memory, and one will be randomly selected for you by the device. "Nonsequential access" would have been a much clearer term. StuRat (talk) 18:30, 18 May 2015 (UTC)[reply]

@@ Line 222: / Line 222: @@
 :[EC] If I remember correctly, the RANDOMATIC was being talked about (mostly to potential invesors) in the film industry in the early 70s, but it wasn't shown until the 1976 Los Angeles SMPTE convention. It was a system developed by The Intercraft Corporation in NYC and Randomatic Data Systems in Trenton. It was a card selector "computer" where bars were raised in selector trays to lift or not lift cards according to holes/notches in the cards. Instead of the usual editor's log book used in producing a film, the cards would contain info on locations. actors, camera, etc. so you can ask "show me all scenes with John Smith on soundstage three using camera B". Card lifting systems predated the RANDOMATIC, so perhaps this was an early prototype or maybe the special effects people just took the idea and made something that resembled it for the film. I will see if the film is available on netflix and watch it. I will be able to tell you more once I see the scenes in question. --[[User:Guy Macon|Guy Macon]] ([[User talk:Guy Macon|talk]]) 18:14, 18 May 2015 (UTC)
+:And note that they are using "random" here to mean "you can select the cards in any random order you decide you want to access them", as opposed to in sequential order.  This is the same way it is used in the term [[RAM]], which is unfortunate, in both cases, because it seems to imply that you will ask for a card or bit of memory, and one will be randomly selected for you by the device.  "Nonsequential access" would have been a much clearer term. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 18:30, 18 May 2015 (UTC)
-:::That picture doesn't look like any real-world card lifting system I have ever seen. I am pretty sure that it was something made by the special effects people just for the film, not a working system. --[[User:Guy Macon|Guy Macon]] ([[User talk:Guy Macon|talk]]) 18:20, 18 May 2015 (UTC)
-::::Found an article about it: [ https://www.questia.com/magazine/1P3-1318941981/editing-a-feature-film-with-the-aid-of-the-new-intercraft-randomatic ] --[[User:Guy Macon|Guy Macon]] ([[User talk:Guy Macon|talk]]) 18:26, 18 May 2015 (UTC)

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