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December 12

Is there an Internet forum thread with ≥100,000 posts?

≥200,000? ≥a million? Sagittarian Milky Way (talk) 23:13, 12 December 2017 (UTC)

Posts made by humans? (((The Quixotic Potato))) (talk) 23:53, 12 December 2017 (UTC)

Yes by humans (though thanks for the funny image, I hadn't thought of AIs conversing @ kiloposts/second for.. something (data mining?)) Or are there human threads that get resurrected by literally millions of Viagra spams, all competing to be last? Or are you just surprised at the number? I've seen a >32,000 post, >1,600 page human thread (no spam) over a decade old but I don't know how big that is in the grand scheme of things. Sagittarian Milky Way (talk) 01:15, 13 December 2017 (UTC)

The forum index at https://www.thesamba.com/vw/forum indicates that the Bay Window Bus forum has a post count in excess of 1 million. Kreemoweet (talk) 04:39, 13 December 2017 (UTC)

The Dutch Fok! forum (which currently has 2,415,432 threads and 175,784,371 reactions) has several topics with more than 100,000 posts. Strictly speaking, threads can only have 300 reactions (a limit hardcoded in the forum software), longer topics are implemented using "topic chains" (basically, when the limit is reached, a user clicks "new part", which creates a new thread with the same opening post and title, adds a sequence number to the title or increments the value if already present, and adds navigation links to the previous part and to a listing of all previous parts). In the Music subforum, "Radio 49" topic (about Fok! webradio) currently has 2210 "parts" or more than 662,700 (300*2209) posts, "Gitaristentopic" (guitar players topic) more than 180,000 posts, and "Wat luister je nu" ("what are you listening now") more than 700,000. Crisis in Syria and Irak in the News subforum has 448 parts (> 120,000 posts). The "Polcafé" topic in Politics (a slow chat topic) is probably the longest one, started in december 2002 and has 7671 parts (> 2,300,000 posts). Prevalence 14:04, 17 December 2017 (UTC)

December 13

Regex for Linux ifconfig

ipa=$(ifconfig | grep -Po "inet addr:\K[0-9]?[0-9]?[0-9]?\.[0-9]?[0-9]?[0-9]?\.[0-9]?[0-9]?[0-9]?\.[0-9]?[0-9]?[0-9]?")

This brings both external IP and internal (loopback) IP. Why does the loopback being brought as well? I can use another grep to remove it, but I'd prefer not to, if I have the option. ClinicalCosmologist (talk) 08:06, 13 December 2017 (UTC)

• The question seems to complain that the regexp matches the loopback IP (which I assume to be 127.0.0.1), but I fail to see why one would expect it not to be matched. By the way, for the IP matching part, it does not matter a whole lot since only "safe" inputs should be given, but the regexp looks awful - I have not tested either but you could shorten it to [0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3} (arguably easier to parse, and avoids matching empty strings for numbers e.g. 8.8..1 is a match of the current), or at least correct the first digit of each to [0-2]?[0-9]?[0-9]?\.[0-2]?[0-9]?[0-9]?\.[0-2]?[0-9]?[0-9]?\.[0-2]?[0-9]?[0-9]? since the IPv4 numbers go from 0 to 255.

I would assume the real question is why does ifconfig return the loopback address. (And the real real question is how to avoid it.) Tigraan^{Click here to contact me} 09:20, 13 December 2017 (UTC)

Thank you for this information, I've learned from that and have implemented the shorter version, it brings the IP just fine. I also added grep -Po -m1 to make sure to stop in the first match, which is the external IP. I need for a small Bash script, I prefer to avoid giving further details. Again thank you dearly for your help. ClinicalCosmologist (talk) 10:37, 13 December 2017 (UTC)

In the shorter version posted by Tigraan above, you should escape the dots, as you did in your original version, since an unescaped dot will match any character. Also, by using -m1, you are relying on ifconfig printing the external IP address first. If it happens to print the loopback address first, this won't work. It would be safer to use something like grep -Po 'inet addr:\K\d{1,3}\.\d{1,3}\.\d{1,3}.\d{1,3}' | grep -v '127\.0\.0\.1' And of course if there are multiple external addresses, all of these solutions will fail, but without knowing more about what you are doing I can't comment on how you should handle that. CodeTalker (talk) 16:02, 13 December 2017 (UTC)

Duh! Yes, of course, the dots should be escaped. (How did I even fail to do that when the exemple given did it correctly?) Tigraan^{Click here to contact me} 17:15, 13 December 2017 (UTC)

Use Microsoft Word 'manage sources' feature to automate Chicago footnotes

Hi, I'm writing a paper using Chicago style footnotes. How do I use the 'manage sources' feature to automate these? As far as I can tell, the Chicago option there will only do bracketed citations, not footnotes... Amisom (talk) 17:56, 13 December 2017 (UTC)

Bing and Google Problems?

After today's Windows 10 update, I can't seem to connect to either Google or Bing. Other websites are fine. All I get is

This site can’t provide a secure connection

www.bing.com uses an unsupported protocol.
ERR_SSL_VERSION_OR_CIPHER_MISMATCH
HIDE DETAILS
Unsupported protocol
The client and server don't support a common SSL protocol version or cipher suite.

Rojomoke (talk) 23:40, 13 December 2017 (UTC)

Resolved

A reboot and a reinstall of my anti-virus seems to have fixed things. Rojomoke (talk) 19:34, 14 December 2017 (UTC)

December 14

Computerized ordering of Chinese characters

At work yesterday I sorted a very long Excel sheet of book titles from numerous languages, and as expected, all the Chinese characters showed up together at the end. As far as I could tell without examining it closely, titles with similar characters were adjacent to each other; in particular, I marked duplicates (Conditional Formatting), and they always appeared next to each other, even though they'd not been adjacent before the sort.

How do Excel and other major English-language-developed programs sort Chinese characters? Is it typical to represent them with ASCII characters (e.g. sorting them by their binary representation), or do some such programs have a sense of stroke order? I'm talking about general-use programs, rather than software that is primarily linguistic. Nyttend (talk) 13:29, 14 December 2017 (UTC)

There are two main ways.

• Sorting by byte order, on the encoded form of the characters. This typically works quite well within a character set, but is case sensitive, works badly between two character sets and badly between mixtures of character sets (such as accented é relative to e). It is technically easy though, robust and repeatable for a full Unicode range, even in legacy systems that are based on 8 bit ASCII encodings.

If you can achieve nothing else with a software project, make it UTF8-clean end-to-end, so that at least it doesn't break anything.

• Collation is an important feature for any database these days, or other systems that take any sort of serious effort over text comparisons. The sophistication of the collation varies (I don't know Excel's offhand) but it begins with such simple processes as case-insensitivity, é vs e and the likely issues for European languages. Going outside Europe (or even into Cyrillic Eastern Europe) depends on vendors. Programming language support does not typically extend this far - you're looking at higher level services, like databases.[1]. Going beyond Europe into CJKV still requires care: a recent platform offering full Unicode support might work, but there are still plenty of major packages which will break here.
• As to radical-and-stroke sorting, it's hard to even have that conversation within the software industry. Finding support for it is rare, finding a large system where such things work correctly end-to-end (where there might be products from two dozen vendors involved) is almost unheard of for software developed in Europe. Most annoyingly, it tends to stop working in European software that successfully implements it, but goes into a 'maintenance phase' (not an Agile concept) where management no longer understand or support proper i18n. It's a bit better on the US west coast, but really the main principle is always that, "If we don't use it ourselves, the ability is soon lost." Post-Brexit, some large UK suppliers are already claiming 'advantages' that this expensive internationalisation will no longer need to be supported. Andy Dingley (talk) 16:57, 14 December 2017 (UTC)

Excuse my ignorance, but is stroke order not simply (part of) a recipe for forming the glyph corresponding to a given character? I would assume that an ordering of words would be based only on the resulting character, not on the way it was produced. As such, I would assume a fixed ordering of characters, and by lexicographic extension, of words. If UTF captures that particular order is a different question, but that would only need a simple transposition table. Am I missing something? --Stephan Schulz (talk) 17:44, 14 December 2017 (UTC)

Radical-and-stroke sorting has a long tradition within Chinese and Japanese calligraphy, Four-Corner Method another fairly established history. Children learn them this way, character dictionaries are ordered this way. It's more than a simple way of ordering glyphs, such as counting descenders in Latin characters would be (possible, but with no established practice behind it).

Technically it's not even that hard to do it. What's needed is interest and commitment from the software vendors. Andy Dingley (talk) 18:02, 14 December 2017 (UTC)

Ok, I looked up Radical-and-stroke sorting - quite interesting, thanks. But as I understand it, it again induces a way to order the characters - very useful for humans, who then don't need to remember an arbitrary ordering of a large set of characters. But for a computer, remembering an arbitrary order of some few thousand characters is not really a problem nowadays. Of course, I assume the set of characters is fixed and finite - maybe that is my mistake? --Stephan Schulz (talk) 17:22, 15 December 2017 (UTC)

Thanks for the pointer to radical-and-stroke sorting; I'd conflated the two concepts and thought that the way you write a character and the way it's organised in the dictionary were related. Nyttend (talk) 01:35, 16 December 2017 (UTC)

• These are interesting too:

• Chinese typewriter anticipated predictive text, finds Stanford historian, Stanford Report, November 28, 2012
• Thomas S. Mullaney (October 2012). "The Moveable Typewriter: How Chinese Typists Developed Predictive Text during the Height of Maoism". Technology and Culture. 53 (4): 777–814. doi:10.1353/tech.2012.0132.

Andy Dingley (talk) 12:19, 17 December 2017 (UTC)

Using undefined variables

If a computer program is confronted with an unknown variable, couldn't it just wait-and-see instead of raising an error?

For example, a=b+b followed by b=8 would raise a NameError in Python. But b=8 followed by a=b+b is OK. Couldn't Python just remember that the value of a is 2b and wait until it is needed as a numerical value and, if it does not get the value, then raise the error?--Hofhof (talk) 18:15, 14 December 2017 (UTC)

In procedural languages like Python the equals sign '=' means something quite different from in mathematics. It means assign the value of the right hand side to the variable on the left. The value of the variable can be changed to something quite different a few lines later. See Procedural programming. Dmcq (talk) 18:22, 14 December 2017 (UTC)

(ec) Well, it could, but it would be a rather strange thing to do, and might go against the principle of least astonishment. The statement a = b + b in Python (and its equivalent in other procedural languages) means 'calculate the current value of b + b and assign that to the variable a, not 'define a to be the whatever the value of b + b is when a is referenced. By that logic, the statements b = 8, a = b + b, b = 16, print (a) might be expected to output the value 32. AndrewWTaylor (talk) 18:25, 14 December 2017 (UTC)

Some computer languages do support this; it's called Lazy evaluation.-gadfium 18:54, 14 December 2017 (UTC)

Lazy evaluation applied more to functions, which may not be computed until the results are required. Computer algebra system may be more useful to you. Mathematica is an example of a language/system which can support statements similar to your example.-gadfium 19:03, 14 December 2017 (UTC)

Declarative programming languages do this sort of thing. In these b = 8, a = b + b, b = 16 would be wrong because b is declared twice, but a = b + b, b = 16 is okay and sets a to 32. Dmcq (talk) 23:22, 14 December 2017 (UTC)

That would be unnecessarily complicated. It is best if it knows what b is when it reaches a=b+b. Bubba73 ^{You talkin' to me?} 22:33, 14 December 2017 (UTC)

• As noted, declarative programming (and its sometimes massive overheads) are there for this. It's not normally needed, so why support a costly feature that's not needed? In this case, a simple function definition or even a lambda would do the job far more simply (and more pythonically).

More importantly, why would you write code this way? Chances are that you didn't mean to, it was an accidental typo. In which case 'failing early' during compilation is by far the better strategy, allowing the mistake to be corrected. Maybe a is required to be 16 and a later assignment of b = 7 (and implicitly then setting a to 14 instead) would rain fiery death down upon the metropolis. Andy Dingley (talk) 23:47, 14 December 2017 (UTC)

While Python doesn't work this way, I can imagine a language that does, allowing for "spreadsheet-like" programming. A language like Prolog also finds out by itself in which order to do the evaluation.

 //Define formulas
 P=I*V; 
 R=V/I;
 //Fill the knowns
 AskAndFill("Do you know Voltage",V) 
 //etc for Power,Resistance, Current
 If R.HasValue Print("Resistance (Ohms) is " + R)

Joepnl (talk) 00:03, 15 December 2017 (UTC)

Yea, well at "a=b+b", it doesn't even know what type b is. You might have to keep b undefined (and every one similar) for a very long time. And then a depends on b, and c may depend on a, and d may depend on c, etc. Bubba73 ^{You talkin' to me?} 02:52, 15 December 2017 (UTC)

And what about "a=b+c", with neither defined. What if later b is set to a string and c is set to a number? Bubba73 ^{You talkin' to me?} 23:46, 15 December 2017 (UTC)

That's probably a good time to raise an exception, or less subtle, decide to treat c as a string in "a=b+c". I don't understand why remembering "b is referenced by equation X" without knowing the future type of b would be a problem? If you want to be asolutely sure at compile-time, replace R=V/I by R(double)=V(double)/I(double) which says that it must be impossible to assign a string to V. Joepnl (talk) 00:46, 16 December 2017 (UTC)

It is a lot of unnecessary work that could be caught at compile time. I think it is also bad design. Bubba73 ^{You talkin' to me?} 00:59, 16 December 2017 (UTC)

Unless you have 40 formulas and don't know in advance in which order they should be executed. CanStartCar=SittingInCar and HasKeys. CarNeedsStarting=NeedToDrive. NeedToDrive=NeedToBeAtShop and not CurrentLocation.IsShop, etc. It is a mixup of declarative and imperative languages, which I don't like actually, but I can see that it could be useful. Joepnl (talk) 01:18, 16 December 2017 (UTC)

I once wrote a little command language for running SPICE scripts where one could write values like 3V or 30pF for instance and it would do dimensional checks in calculations. Dmcq (talk) 10:54, 17 December 2017 (UTC)

Resetting default PDF reader in Windows 10?

On my home PC, I'm running Windows 10 (professionally re-installed a week ago after an unrepairable startup error appeared). When I want to open a PDF document already downloaded, this currently defaults to using Microsoft Edge, with various alternatives also offered.

I would prefer not to use a browser program or this, but instead to use LibreOffice 5.4, which I have on the computer and which can open PDFs in its Draw application, but this is not one of the options offered.

While I can open LibreOffice Draw and then search for and open a given PDF document, I cannot figure out how to make it my .pdf default such that I can first go to the document and then open it with LibreOffice 5.4 as the default or even an alternative option.

If I go to Windows 10's

Settings, Apps, Default apps, Choose default applications by file type,

then .pdf is already set to Microsoft Edge with no way I can see to change that to anything else.

Suggestions? (Please keep things as untechnical as possible!) {The poster formerly known as 87.81.230.195} 90.220.212.173 (talk) 21:00, 14 December 2017 (UTC)

I'm not an expert on this, but if you get to settings/"Choose default apps by file type", the application extensions are listed in order on the left. Go down to "pdf", click the icon to the right. Then it should give you choices of the software you have installed. Bubba73 ^{You talkin' to me?} 22:30, 14 December 2017 (UTC)

In my experience you can install whatever PDF reader your like (Evince, Adobe Acrobat, etc) but W10 will constantly reset the default to Edge. It seems to me that Microsoft decided that they know best when it comes to what to open a PDF file with. You can fix this, but you're going to have to get you hands dirty with Regedit

• regedit HKEY_CURRENT_USER\SOFTWARE\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppModel\Repository\Packages\Microsoft.MicrosoftEdge_25.10586.0.0_neutral__8wekyb3d8bbwe\MicrosoftEdge\Capabilities\FileAssociations
• look for magic number next to pdf
• regedit HKEY_CURRENT_USER\SOFTWARE\Classes\<Magic number>
• in the right hand pane, create a new string value - NoOpenWith
• repeat for html, htm, etc

HTH --TrogWoolley (talk) 10:53, 15 December 2017 (UTC)

Thanks for responding, Bubba73 and TrogWoolley. When I follow Bubba73's procedure (which I'd already tried, the displayed icon being that for Microsoft Edge), the choices offered are Microsoft Edge, Firefox, and Look for an app in the store. When I now click that third option, I'm offered a choice of 293(!) apps, many of which are free, but none of which are LibreOffice which I already have and can use in the non-default mode described above.

TrogWoolley's suggestion is a long way beyond the limits of my technical comfort zone, and having just paid £65 to a professional shop for an investigation and eventual Windows 10 reinstall (which I could perhaps have attempted myself, but didn't dare) to correct the aforementioned startup fault, I lack the financial fortitude to essay it.

I'll probably stick with opening LibreOffice and then searching for the desired document, rather than opening the document directly. I'll also consider migrating to Macintosh some time in the future: Microsoft is getting too nakedly feudal for my taste. {The poster formerly known as 87.81.230.195} 90.220.212.173 (talk) 11:08, 15 December 2017 (UTC)

I have had Adobe Reader as my default PDF reader for nearly a year now, and before that on a different installation for I think the same amount of time or more. (Also most of my other defaults are not Microsoft's choices.) From my experience on Windows 10 Pro, which seems to be supported by (nonRS) refs [2] [3], if you set a default program yourself it stays. The only time it tends to change is possibly for major upgrades (e.g. Creator's update etc) and when something messes with the default programs.

Windows 10 doesn't like other stuff messing with the defaults, and if it detects this it will reset to the original defaults (recommended programs). If you keep installing junky programs that don't understand this or your installed programs are junky and still don't understand this and you give them admin access, then you will have problems. If not, you should not have to fool around with the registry. In other words, the solution recommended above should work fine for any program which has registered itself as being able to open PDFs, provided you aren't installing or running junky programs, with the slightly possibility of needing to fix it every half year or so at worse after major upgrades. (IIRC this only happened once or twice due to new programs or some other reason.

Now if your program has not registered itself as supporting PDFs it's a little more complicated mostly since Microsoft are trying to push you to store apps, although you still shouldn't need to fool around with the registry. One simplish solution is to right click on the file and look for the 'open with' option. Mouse over and in the submenu there should be an option to 'Choose another app'. As an alternative, if you select a PDF file and then go to the home tab, there should be an arrow next to the Open option, and you can also click on 'Choose another app' here too.

Either way, you should now get the list of apps registered as opening that file type. Scroll down to the bottom and there is a 'More apps' option. Clicking on that will show other apps, I think any that are set as defaults for any file or something. Maybe whatever you want to use will show up here. If not, scroll down to the bottom and there is a 'Look for another app on this PC' option. You will then need to browse to the program that you want to use to open PDFs. (With modern programs, this can sometimes be a little complicate if they have multiple executables, and you're not sure which is the right one.)

Nil Einne (talk) 11:40, 15 December 2017 (UTC)

Hello, Nil Einne: Thanks for this. I'd got as far as 'Look for another app on this PC' and searching to find the Libreoffice file, but then couldn't figure out how to open the document in it. Encouraged by your advice, I've now gone on to drill down to LibreOffice's 'sdraw' sub-subfile and open a document, and now LibreOffice has been added to the other two main options (Edge and Firefox) offered under 'open with' when I right click on any PDF document. Not quite the default, but close enough for my needs.

Thanks again to yourself, and to Bubba73 & TrogWoolley. I'll mark this as . . .

Resolved

{The poster formerly known as 87.81.230.195} 90.220.212.173 (talk) 12:29, 15 December 2017 (UTC)

December 15

Alexa / Echo gadgets

They have these Alexa / Echo gadgets. Do they sell these with foreign languages? Or is there some setting that changes the language from English to some other foreign language? I'd like to buy one as a gift for someone else, but I don't want it to be used with English verbal commands. I want it t work with commands in a foreign language. Specifically, Italian. Thanks. 32.209.55.38 (talk) 15:18, 15 December 2017 (UTC)

Confim German language of Alexa. --Hans Haase (有问题吗) 16:04, 15 December 2017 (UTC)

When I looked at Alexa this past summer, it had American English, UK English, and German. They said Spanish was coming next. 209.149.113.5 (talk) 16:57, 15 December 2017 (UTC)

Thanks, all. So, no Italian, then? 32.209.55.38 (talk) 19:33, 15 December 2017 (UTC)

December 17

IBM z/OS and other mainframe operating system

I was looking at this YouTube video to see what IBM z/OS is like, because there's no chance I'm ever going to afford a zEnterprise system of my own.

What immediately struck me is how weird-looking the interface is. It's nothing like any operating system I have ever used, which include AmigaOS, MS-DOS, Windows and Unix (Linux and Sun Solaris). Is this really what z/OS looks like? Or is it some programming environment inside it?

How does one even use z/OS? How does one run programs, access files or access the network? JIP | Talk 10:06, 17 December 2017 (UTC)

Don't dismiss your dream, be more positive, this youngster bought his own IBM mainframe -) This Teenage IBM Employee Got His Job By Buying An Old Mainframe Computer. If you're too frightened by that idea you could start small with the The Hercules System/370, ESA/390, and z/Architecture Emulator. And yes, that is what it is like. Dmcq (talk) 10:30, 17 December 2017 (UTC)

I see that that guy managed to buy an IBM z890 for less than one-thousandth of its original price. Still, he had to have his parents help him transport it to their basement, and even getting it to boot up was difficult. I think that is way too difficult and too much work for me. I'm using a used HP Z420 professional workstation as my personal desktop, and I'm perfectly happy with that. I'm reading IBM's own "Introduction to the new mainframe: z/OS basics" guide as a PDF, and am finding it all very difficult. The only operating systems I have ever used are those I mentioned earlier: AmigaOS, MS-DOS, Windows and Unix, which are all file-based and command line -based, rather than this weird record-based and menu-based z/OS. I downloaded and installed Hercules, but I couldn't even get it to start without copy-pasting an example hercules.cnf configuration file, which I didn't understand anything about. And even that only got me as far as Hercules' own command line, it didn't even boot any operating system up. I guess trying to learn mainframe operating systems is too difficult to be worth my time. JIP | Talk 23:49, 17 December 2017 (UTC)

You do have to be a bit of an enthusiast to run emulators for systems like that, well for any emulators. As for running one's own mainframe like that person - that's just amazing. Those systems started up originally in the 1960's and have just changed slowly since then as the companies running them want consistency and don't like sudden changes. They do run a version of Linux as well and that is much more approachable. Dmcq (talk) 00:55, 18 December 2017 (UTC)

Pedantry alert: "record-based" is not the antonym of "file-based". A record-oriented filesystem is one way of handling files (and the way IBM and most mainframes have always done it); the other is byte-oriented, as on Unix, where files are just treated as bags of bytes. Note also that z/OS itself isn't really "menu-based". z/OS doesn't care how you talk to it. ISPF is what's menu-based, and using it is optional, though common. Menu-based console programs like Midnight Commander are used on other platforms. (And then there's emacs, which is practically an operating system on its own.) --47.157.122.192 (talk) 10:08, 18 December 2017 (UTC)

The video depicts the use of ISPF. Most of the video is the user working inside ISPF, editing a COBOL program and the JCL commands for executing it. You run programs, access files, and access the network the same way you do on any computer with an operating system: by using the operating system's facilities for doing so. ISPF and TSO aren't wildly different from command-line interfaces on other platforms. z/OS is fully POSIX-compliant, so you can even run a Unix shell on a z/OS system. The Art of Unix Programming has a chapter that contrasts Unix with other OSes, also giving a brief overview of each's design: here's the section on MVS (the core of z/OS and earlier IBM mainframe OSes). --47.157.122.192 (talk) 10:08, 18 December 2017 (UTC)

JES2 comes with zOS for free. Operators use SDSF to start programs (I've never used it). Larger shops pay extra to use JES3. Operators can start started tasks or they can submit jobs from ISPF.
Sleigh (talk) 09:50, 18 December 2017 (UTC)