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January 14

GPS Vehicle Tracking

I have a truck fitted with gps. Once the vehicle is loaded with goods an automatic entry (truck loaded:with place and time) should be made in my home computer. And same when unloading. Is it possible to do? Is there any software which can help me? — Preceding unsigned comment added by 117.216.166.50 (talk) 11:15, 14 January 2016 (UTC)

Possible? Sure. Software? You'd probably need something custom. A service like Life360 will record the GPS location at all times. The driver can check-in to highlight locations. You can look at the GPS history of the truck and see where it was all day and when it had check-ins. You can also set locations and get a text or email alert when the truck arrives and leaves set locations. 199.15.144.250 (talk) 13:46, 14 January 2016 (UTC)

I guess the problem here is that while the truck knows where it is - GPS can't tell you that it's being loaded or unloaded - and with just a GPS unit, there isn't a way to transfer that information to your home computer. So you'd need something more complicated than just that. Instead of just a GPS, you'd want to use a cellphone - which includes a GPS and also has the means to send the results elsewhere. You'd also need to find a way for this device to conclude that the truck is being loaded or unloaded rather than just stopping some place en-route for donuts. Automating that by (let's say) measuring the weight of the truck would be difficult with off-the-shelf equipment - so you'd probably be reduced to knowing that it's been stationary for a certain amount of time within some specified distance of the known loading and unloading locations.

You could just have the driver send a text message when loading or unloading - using the hints HERE, you can arrange to have the GPS coordinates included in the text message - the time is already there. Providing your drivers actually do this, you'd have pretty much all you need.

SteveBaker (talk) 15:40, 14 January 2016 (UTC)

If the truck is being completely unloaded each time, there are several options, e.g. a light gate or a simple pressure sensitive switch. Takes a bit of fiddling to get the signal out, but nothing too hard. Might not be the most reliable unless you can ensure that the switch is always active when there is stuff in the truck, and nothing can activate the switch when it is unloaded (e.g. the driver putting their lunchbox in the back). If you don't mind adding some steps for the driver, then barcodes/RFID on the packages and a barcode/RFID scanner (which can just be a smartphone camera/NFC reader) could be used to mark what is unloaded and loaded. Either way, it's probably going to take some custom software to get what you want. MChesterMC (talk) 16:56, 14 January 2016 (UTC)

Well, a truck has no scale installed inside the suspension, but opening a door is an event. When grabbing the NMEA protocol lines from the GPS, send the last line when the door opens. --Hans Haase (有问题吗) 21:11, 14 January 2016 (UTC)

Opening the doors are an event, but even if restricted to certain locations and requiring the door to be open for certain periods of time you are still likely to get inaccurate results unless the door is really only ever opened once for loading/unloading and closed soon after the loading/unloading is completed and never opened again for long periods until the next loading/unloading. If the door is opened for loading/unloading then closed again when the people go to lunch, you're likely to get confusing results. Or if you can't really program every place the truck is likely to be loaded/unloaded or some loadings/unloadings are likely to be short. It depends significantly on what the OP is trying to do, the size of the truck, the behaviour of the people involved, how bad it will be to have the occasional wrong or confusing results etc. Nil Einne (talk) 15:58, 15 January 2016 (UTC)

When a courier guy delivers a package, he says me to sign on his mobile. and after signed, package delivered is updated on their website . What is the software they use? I feel that I can use that idea for loading/unloading. — Preceding unsigned comment added by 59.88.196.26 (talk) 17:56, 15 January 2016 (UTC)

Do you need the same knowledge or steps to compile and decompile (or to assemble and disassemble)

Is compilation and de-compilation (or assembling and disassembling) just like the difference between 3 * 4 and 4 * 3? Or is it like the difference between multiplying 101701 by 101719 (= 10344924019) or factorizing 10344924019 (factors 101701, 101719)?--Llaanngg (talk) 15:34, 14 January 2016 (UTC)

We could come up with lots of clever analogies, but it would be best to refer you to a book on computer theory or compiler design... why don't you start with Patt and Patel? It's a great book for beginning to understand the great depths of computer systems theory.

You can think of a compiler as a piece of software that implements a mathematical function to project from one set onto another set; this is strictly the part of the compiler called "translation." This mapping function is neither complete, nor "one-to-one" nor easily-invertible; so the process of "decompiling" is not well-defined. That leaves a lot of room for interpretation. It is probably not a good idea to confuse this ambiguity even further by introducing complicated and tenuous analogies.

Nimur (talk) 15:48, 14 January 2016 (UTC)

OK. I'll check the ref. Llaanngg (talk) 15:51, 14 January 2016 (UTC)

Compilation and assembling is an automatic process - no special skill or knowledge is really needed. De-compilation and dis-assembling is a much harder process. Firstly, the compilation/assembly process throws away a ton of information that you simply cannot get back. Typically, you'll lose the names of all of your variables - so you start with:

  double Pythagoras ( double width, double height )
  {
     // Calculate the length of the hypotenuse of a right triangle
     double hypotSquared = width * width + height * height ;
     return sqrt ( hypotSquared ) ;
  }

...and after compilation and de-compilation, you might get something like:

  double f1 ( double v1, double v2 )
  {
    double v3 = v1 * v1 ;
    double v4 = v2 * v2 ;
    double v5 = v3 + v4 ;
    double v6 = f2 ( v5 ) ;
    return v6 ;
  }

...which would take some skill to understand for what it is.

This is an especially simple example - in the real-world, it's vastly harder because we have things like inlined functions, automatic loop unrolling, memory location re-use, statement re-ordering, register use optimisation.

These things destroy the original human-readable code and produce something that is best for the CPU to execute. When you de-compile, its up to the decompiler to try to deduce what humans would prefer to see...but that's often an aesthetic choice - and not one that the decompiler can make.

SteveBaker (talk) 15:51, 14 January 2016 (UTC)

They are not very different really. As you say, decompilers optimize for "understandability", which is less well defined than execution speed/size, but that doesn't mean there's nothing you can do to improve it. A decent decompiler would at least produce something like return f2(v1 * v1 + v2 * v2); rather than your five-line version. A better one would recognize that f2 is a standard library function and automatically rename it to "sqrt", and an even better one might recognize f1 also.

The main thing that makes decompilation of x86/ARM/etc. difficult is that it's impossible to prove the correctness of most transformations, because it's so open-ended what machine code is allowed to do. Any instruction could be the target of a computed jump, for example. Most surely aren't, but generally you can't prove it. But this isn't a problem of all decompilers, or only decompilers. Java bytecode is much easier to decompile, and Python is very difficult to compile. -- BenRG (talk) 21:58, 14 January 2016 (UTC)

Do you mean Python is difficult to decompile, that is, the python bytecode? I suppose compiling is also difficult, but that's the same case of any dynamic language by design. Denidi (talk) 00:11, 15 January 2016 (UTC)

Mobile Phone Blocking

Do hospitals in the UK block mobile phones, and if so, how? KägeTorä - (^影_虎) (もしもし！) 16:35, 14 January 2016 (UTC)

They prohibit using them to breach privacy of patients. They don't block them. They could using a really big Faraday cage, but they don't. How can you tell? Go to the hospital and use your phone. 199.15.144.250 (talk) 17:05, 14 January 2016 (UTC)

Many schools in the US have blocked cell phones without the need for a gigantic Faraday cage. See Mobile phone jammer. Dismas|^(talk) 18:17, 14 January 2016 (UTC)

Do you have any reference for this Dismas? I doubt they can do this legally. Cell-phones are an authorized and licensed technology, which could be literally life-saving in an emergency.

According to the fcc site "CONSUMERS BEWARE: It is Unlawful to Use “Cell Jammers” and Other Equipment that Blocks, Jams, or Interferes with Authorized Radio Communications in the U.S."

--Scicurious (talk) 19:07, 14 January 2016 (UTC)

They've run into problems with parents, of course. This is just one related story. I'm sure I could find more about schools proposing this, at least, if I looked for a bit more. Dismas|^(talk) 00:30, 15 January 2016 (UTC)

The article you linked to doesn't say that at all. They have not run into problems with parents. Of course not. Parents could even agree with such measures and anyone is free to propose it. It remains illegal. The teacher was suspended for 5 days without pay since he wrongly assumed that jamming is only illegal if used with a malicious intent. Silly guy. Please read the FCC link above. No school in the US can do this legally. --Scicurious (talk) 01:27, 15 January 2016 (UTC)

Yeah I think the take away message from this is teachers, parents, administrators and boards can propose whatever they want. Hopefully before they actually implement it, they'll take legal advice or at least do an internet search and find like these people did [1] [2] (see comment by Lefttowonder) they're likely to have problems if they try. It sounds like teachers at least often get off lightly, per the earlier source and [3] and possibly others who don't do anything too out there (e.g. I don't see any mention of fines for anyone but the seller here [4]. Still not something to mess with. Note the FCC document mentions that even local and state law enforcement can't use jammers without permission. Nil Einne (talk) 16:36, 15 January 2016 (UTC)

They are also illegal in the EU, but there are special circumstances, such as use in British prisons. 199.15.144.250 (talk) 20:13, 14 January 2016 (UTC)

Notepad file size

According to this, a file should not exceed 45K in Notepad. What is that in pages? Thanks, Dismas|^(talk) 18:13, 14 January 2016 (UTC)

"Pages" of what? Are you talking about memory pages? If you mean "pages as printed on paper", there is no answer to that question. Notepad is a text editor that edits plain text files. How many pages text will take up when printed depends on a whole bunch of things that are independent of the text, like the font size chosen for printing, paper size, margins, and so on. Now, some "document publishing formats" like PostScript (which is used in PDF) do arrange the document in terms of pages; they're intended to represent a document in a fixed, device-independent matter. This might be where you're getting the idea from. Doing this involves adding instructions to the file describing the layout, which the computer follows when it renders the document. Plain text files don't have any of this. They're "just text". --71.119.131.184 (talk) 19:13, 14 January 2016 (UTC)

This Knowledge Base article applies to Windows 3.0 (et al.), which ran on (mostly) computers of the Intel 386 vintage. Those systems ran with complex, segmented memory management, so page size is not as clean as it is on newer processors that we lump in as "x86" systems. For most practical purposes, you could categorize the Windows 3.x memory model as one that used 4096-byte pages.

Nimur (talk) 19:17, 14 January 2016 (UTC)

1 kilobyte = 1000 bytes, and a letter can occupy 1 byte (or more). If we assume the average word to be 5 letters long, that gives us 200 words by kilobyte. That is, your 45K is equivalent to only one page. That seems too little, even by Microsoft standards. Are you using notepad or notepad++? I suppose probably the last one.--Scicurious (talk) 19:18, 14 January 2016 (UTC)

How do you make the jump from 200 words per KB being one page? That would equate to 9,000,000 words. Are you claiming there are 9 million words per page? 199.15.144.250 (talk) 20:18, 14 January 2016 (UTC)

Think you made a mistake somewhere. 200 words per kilobyte and 45 kilobytes means 9000 words. That said the Scicurious does seem to have an excessively high expectation of words per page. A search suggests 500 for single space A4 with reasonable margins and font size. They also forgot punctuation, particularly spaces. And as a minor nitpick, I'm fairly sure the ancient Microsoft document is using 1 kilobyte = 1024 bytes not 1000. Nil Einne (talk) 21:32, 14 January 2016 (UTC)

Sorry, got the rate of words/page wrong. 500 seems reasonable. So, 18 pages for the 45K.--Scicurious (talk) 21:45, 14 January 2016 (UTC)

Notepad++ helps. --Hans Haase (有问题吗) 20:04, 14 January 2016 (UTC)

Fairly sure Notepad++ does not now and has never supported Windows 3.x. V1.0 was released in 2003 after all, post XP. It's open source so guess you could port it, but why? Admittedly the limit isn't much better in 9x still the OP was referring to a 3.x document. The limit in XP and newer versions of Windows is quite high [5]. IIRC Notepad++ isn't much higher if at all, so while there are advantages of Notepad++ I'm not sure file size limits are one of them. Except perhaps in 9x, presuming any versions of ++ work in them. Both need to load the entire file to memory although Notepad++ is possibly a little faster at processing IIRC. If really working with very large text files bigger than 1GB, it may be better to use something which doesn't need to load it all to memory. Nil Einne (talk) 21:57, 14 January 2016 (UTC)

January 15

Copyright and Snowden

Why was Snowden charged with "theft of government property"? I understand why he was accused of being a spy, but isn't any document produced by the government automatically in the public domain, even if not on the internet? Unless he indeed stole some computer, I don't get why the theft charge. --Scicurious (talk) 14:42, 15 January 2016 (UTC)

Public domain relates to copyright only. Despite what all those ads from the MPAA etc say, people aren't charged with theft over copyright issues. Nil Einne (talk) 15:12, 15 January 2016 (UTC)

Yes, copyright infringement does not lead to a theft charge, it leads to a copyright infringement charge, besides civil penalties.--Scicurious (talk) 15:31, 15 January 2016 (UTC)

Yes, so the point is public domain is likely irrelevant. There's no suggestion copyright is involved, plenty of reasons to think it isn't. Nil Einne (talk) 16:40, 15 January 2016 (UTC)

I'm not sure anyone knows. Aside from the mere list of charges, I think the details of the allegations are still sealed. It could be alleged that he took a hard drive, or physical papers, or just about any object really. Dragons flight (talk) 15:19, 15 January 2016 (UTC)

Yeah was going to say the same thing. I did a search, and while I found one or two searches criticising the charge like [6], the best comment I could find was by a commentator here [7] left at June 23, 2013 at 3:39 pm which says something similar to Dragons flight. We don't know precisely how the government claims to have established the elements for the theft charge because they haven't publicly revealed it. From what I can tell, this hasn't changed, and probably won't change until Snowden either returns to the US to face the charges, or perhaps if the government drops them for some reason. Nil Einne (talk) 15:27, 15 January 2016 (UTC)

It seems then, that's all the non-speculative information we can get. Scicurious (talk) 15:31, 15 January 2016 (UTC)

I did find [8] from 2014 which seems to confirm that at the time the case remained sealed. (N.B. I'm not endorsing other aspects of that source.) I'm fairly sure it must remain sealed now, otherwise I would have found something new. Besides the possibilities I mention above, if an extradiction proceeding ever gets under way and is challenged by Snowden, it's likely some details would have to be revealed to the foreign court. This doesn't guarantee it will be made public, but in a number of countries it may be difficult to prevent an outline being made public unless there's a very good reason. Consider the Megaupload legal case for example. Nil Einne (talk) 15:51, 15 January 2016 (UTC)

Mr. Snowden was charged with theft of government property because attorneys for the United States Government believe he stole government property. In this statement, the Justice Department outlines its charges, which were made in a criminal complaint to the federal court in the Eastern District of Virginia. Among the complaints were charges that Mr. Snowden committed unlawful acts as defined in 18 U.S.C. § 641. There are lots of ways to violate the law, and it is not yet clear which laws - if any - were violated; this is why the case must be tried.

Have a look at §641. One could commit unlawful acts by embezzling, purloining, stealing, "knowingly converting," ... receiving, concealing, or retaining, ... property of the United States. All the attorneys must do is prove that the defendant did any of those things, and they can convict him of a federal crime that may carry a prison term.

Nimur (talk) 16:11, 15 January 2016 (UTC)

"...because attorneys for the United States Government maintain he stole government property". We don't know what they believe, and in this particular case, my good faith does not extend very far any more (it took a first big hit when, shamefully, moral failure John Yoo drafted and despicable human rights violator Jay S. Bybee signed the Torture Memos without causing the mass armed uprising we are promised when the government violates basic freedoms). --Stephan Schulz (talk) 16:39, 15 January 2016 (UTC)

Persons accused of espionage have always also been charged with theft of government property, the classified information, since the Daniel Ellsberg case was dismissed. Ellsberg's defense was that the Pentagon Papers should not have been classified. The US espionage act does not refer explicitly to classified information, but contains a long list that is essentially a classification guide, identifying types of information that should be classified. Ellsberg argued that, since the Pentagon Papers should not have been classified, he was not committing espionage. (Don't attempt this defense in the United Kingdom.) In order to deal with defenses of this sort, since the dismissal of the charges against Ellsberg, the accused spy has always also been charged with theft (of the documents). (By the way, the charges against Ellsberg were dismissed, not because of the issue of whether the papers should have been classified, which never came to trial, but because of misconduct by the prosecution at the instructions of the Nixon Administration.) That is why he was also charged with theft. Robert McClenon (talk) 18:05, 15 January 2016 (UTC)

Online Money

How to earn money by creating a website and where does the money gets deposited? Also what are the other ways to earn money online? — Preceding unsigned comment added by 59.88.196.26 (talk) 17:40, 15 January 2016 (UTC)

You can earn money as a web developer - that is creating a website. The money will be deposited wherever you want it to be deposited. There is no such thing as web pages that magically create money and hide it in a magical pot at the end of a rainbow somewhere. You will need to do some work. As for other ways of earning money online - just get an online job and do some work. If you are looking to make money without working, there are millions of people looking to make money without working. There isn't much free money to go around, so you need to do a hell of a lot of work to make avoiding work profitable. 199.15.144.250 (talk) 17:54, 15 January 2016 (UTC)

You could (possibly) create a website with enough useful content that a lot of people would want to visit it...then you could go to a company like Google and have them pay you to place advertising on the website. However, you need a HUGE number of visitors (tens of thousands per month) to earn even a tiny amount of money that way. I believe Google will direct-deposit money into your bank, or mail you a check once they owe you more than $100 - or monthly if you're earning more than $100/month. However, if you think this is going to earn you a ton of money - you're severely mistaken. That'll only happen if your content "goes viral" and is viewed by millions of people.

You could also use a website to serve as a 'storefront' for some other business (involving products, sales, services - actual work of one kind or another) - in which you could have people deposit money via PayPal or something similar.

But there is nothing magical about making money on the internet...it's not that the internet generates the money for you...you USE the internet to get money from whatever work you put into it. There's no such thing as a free lunch. SteveBaker (talk) 18:23, 16 January 2016 (UTC)

Nonprofit confidence trick

I have a website that I haven't worked on for years (alternativegiving.org), and most of the mails I get for it nowadays is spam. Now I just got a type of mail I have not seen before:

We need not mention the obvious signs that point to a confidence trick. I removed the name (which did not yield any pertinent information) because there is an off chance that it's just a very selfless person who also is clueless. (I'm following my own variant of AGF here, which is why I'm taking your and my time with this message.)

I would like to help protect others, especially since this is targeting nonprofits, for which, as a contributor to wikipedia.org, I obviously have a heart. Should I report this? If so, where? There is http://www.stopfraud.gov/report.html, which says "Fraudulent activities should always be reported to your local law enforcement office.", but I don't want to bother my local police with something like this. The same site also refers to https://www.ic3.gov/default.aspx, but that's only for when you have become a victim. http://www.ripoffreport.com/ seems to be only for consumers. I once reported some suspicious activity on some other site, I forget which, but I never learned what became of it. — Sebastian 17:53, 15 January 2016 (UTC)

It is a waste of time to report it. The only organization that actually tries to help in these cases is the Better Business Bureau. They are very picky on what they do with online businesses. They online company must be owned and operated in the United States, or all they will do is file your complaint away and ignore it. 199.15.144.250 (talk) 17:58, 15 January 2016 (UTC)

Thank you; there's no indication that there is a company behind it, nor that the sender even is in the US. — Sebastian 18:04, 15 January 2016 (UTC)

I wouldn't reply to any such e-mails unless they tell you which organisations they have helped (so that you can find out how much they "helped"). There are many fraudsters who wish to get their hands on genuine websites to add malware. Dbfirs 09:32, 16 January 2016 (UTC)

That is what your junk folder is for but you can use an organization like Spamhaus so others have aren't bothered with the rubbish. Anyone actually doing stuff like that anyway well will be plied with quite enough work in their local area. Dmcq (talk) 14:29, 16 January 2016 (UTC)

In many cases, these people just generate a stock webpage from some automated tool. The webpage itself may be free - but I guarantee there are other charges for "maintenance" or search-engine-optimisation or some such junk. Just ignore them. SteveBaker (talk) 18:06, 16 January 2016 (UTC)

The reason why I posted this was not to ask whether I should reply, or where to move spam, nor to speculate what the senders might do (although that's interesting; what Steve suggested is actually marginally honorable; an option which hadn't occurred to me). No, I posted this here because I believed it's most likely a confidence trick targeting nonprofits, and I want to help protect others and warn them. — Sebastian 20:41, 17 January 2016 (UTC)

@SebastianHelm: Here are a few other places you could report it [9], I would try at antiphishing.org, their aim is mostly to get the word out. You could also try forwarding to nonprofit consortiums and resource centers on social media or listservs. If you google /nonprofit [resource, consortium] [your location]/ you should find a few people who would appreciate the note. SemanticMantis (talk) 17:53, 18 January 2016 (UTC)

Thank you, SemanticMantis, that's exactly what I was fishing for! — Sebastian 19:16, 18 January 2016 (UTC)

January 16

Software

When a courier guy delivers the package, he asks me to sign on his phone. And automatically this gets updated on their website : as package delivered. What is the software they use? — Preceding unsigned comment added by Stalson92 (talk • contribs) 02:28, 16 January 2016 (UTC)

@Stalson92: Since you haven't told us which courier company you're thinking of, I don't see how we could definitively answer this question. There are thousands of courier companies in the world. Perhaps the best course of action for you would be to just call the courier company and ask them. You may need to speak to a supervisor or manager but someone there should know the name of the software. Dismas|^(talk) 14:39, 16 January 2016 (UTC)

FedEx — Preceding unsigned comment added by 103.60.68.122 (talk • contribs) Stalson92 (talk) 15:40, 16 January 2016 (UTC)

Usually, those companies are large enough to develop their own software. It may have an internal name - but I doubt that'll help you much. SteveBaker (talk) 18:04, 16 January 2016 (UTC)

Even with the OPs clarification on company, they still didn't mention a location (geolocation gives India).

I wonder whether FedEx always use the same software anyway or just need it to be able to communicate with their servers via their standard API. While I've only ever received one package from FedEx here in NZ, their system seemed to be similar to what many courier companies here use now (and have been for a few years). I didn't sign on a phone but some specialised terminal.

In some countries and places (including I believe some places here in NZ), FedEx do not have their own drivers but instead rely on deals with other courier companies. It's possible they still require the use of specialised FedEx devices, but it would seem more likely they're fine with these drivers using their own devices which either communicte with FedEx via their API or communicate with the drivers courier company which then connects to FedEx.

I guess the phone thing is useful for temporary drivers and similar and perhaps also where the only want to provide one device (particularly in the developing world where they need to keep costs down and can't assume everyone will have a phone for contact). But even then, I wonder if there are circumstances where they don't use the same software.

And we can't even be sure that the software is universally used, e.g. if it's in English perhaps the Chinese or whatever division found it easier to develop their own software (if they have any) rather than translate it. Particularly if other features don't work well in China (or wherever) for whatever reason.

I suspect the phones the OP referred to were Android; while porting Android apps to Windows is often not that hard (as I understand it), again it may be that someone would find it easier to start from scratch. Windows isn't really that popular anywhere, but if the company is providing the phones it's always possible they could choose Windows ones for whatever reason.

Nil Einne (talk) 12:07, 18 January 2016 (UTC)

Pseudocode mod of a negative integer

In pseudocode, is the mod of a negative number >= 0 (as in mathematics)? In some languages, -7 mod 5 returns -2 instead of +3. Bubba73 ^{You talkin' to me?} 02:35, 16 January 2016 (UTC)

Pseudocode isn't well enough standardized for this question to have a standard answer. As with any other mathematical notation, the author should clarify the meaning where it's ambiguous. Standard mathematical notation has no mod operator. One normally writes x ≡ y (mod p), not, e.g., (x mod p) = (y mod p). -- BenRG (talk) 02:44, 16 January 2016 (UTC)

The book has an appendix about its pseudocode, but it doesn't say. I'm going to assume that the result is non-negative, because a negative value doesn't seem to do any good. Bubba73 ^{You talkin' to me?} 02:57, 16 January 2016 (UTC)

Resolved

Real programmers rarely (if ever) use pseudocode - and then only where there is a gun being held to their heads. It's one of those things like flow charts and UML diagrams that academics fondly imagine should be a good idea and spend endless time getting excited about. In practice, experienced people can read real code (in their preferred language) much more easily than pseudocode - so we just write things in real code to start with and save an unnecessary step. In practical situations, it's almost always the case that the pseudocode contains bugs that aren't noticed until the real implementation is working (because there is no way to compile and test the pseudocode) - and then nobody goes back to fix the pseudocode and it's immediately rendered worse than useless.

That said...

In the unlikely event that you're trying to describe an algorithm in pseudocode without specifying an implementation language - then you'd need to be super-careful about things like that. IMHO, if you need to be portable and you are planning to take the MOD of a negative number - then you should explicitly test for a negative input, and in that case calculate mod(-x) and handle the result accordingly. This makes the process entirely explicit and whoever is given the thankless task of converting pseudocode into real code can choose to optimise this (or not) depending on what their underlying language supports. Either way, a bloody great comment describing what is intended and why - and warning of the anticipated portability issues - is absolutely required here! SteveBaker (talk) 18:01, 16 January 2016 (UTC)

Pseudocode is common in computer science papers. It is usually block-structured like popular programming languages, though you do sometimes see flowcharts. It is useful in the same way as other mathematical notation. It is generally easier to understand an algorithm from a pseudocode description than from a plain-English description or an executable implementation. -- BenRG (talk) 20:33, 16 January 2016 (UTC)

I was trying to translate some pseudocode in a book to a working program. (I found what I think is a typo, but fixing that and making the result of modulo >= 0 and it works.) Speaking of flowcharts, I used them routinely in real programming when I used non-structured languages (e.g. spaghetti Fortran, Basic, and a little Cobol). But when I went to structured languages in 1981, flowcharts no longer applied. Bubba73 ^{You talkin' to me?} 21:29, 16 January 2016 (UTC)

I am a real programmer and, contrary to Steve's experience, I have often found pseudocode a useful tool when drafting the basic algorithm for a procedure. I find it very convenient to write something like

    while any moles are visible {
       find nearest mole to hammer
       move hammer over mole
       whack it
    }

and then translate that into real code. A real-life example would be more complicated than that one, but still no more than around 10-15 lines of pseudocode. --76.69.45.64 (talk) 07:43, 17 January 2016 (UTC)

I agree. Bubba73 ^{You talkin' to me?} 23:06, 17 January 2016 (UTC)

GIMP 2 and animated GIFs

Passive permit traffic signaling in Göttingen, Germany

pictures from camera

I need help understanding some options for saving animated GIFs. In File + Export, with GIF selected as the output type, there are the following options dealing with animation:

Delay between frames where unspecified: ____.

□ Use delay entered above for all frames.

So, does this mean checking the box overrides the "where unspecified" part above ? If not, what does it do ? And is there a way to see which frames have their own delays specified and change them individually ? StuRat (talk) 03:27, 16 January 2016 (UTC)

GIMP converts the layers of the picture to an animated GIF picture. The delay is framerate of the flip book.[10] Use delay entered above for all frames. is a constant flip rate of the layers. GIF is compressed file format. If there's no change for longer, the best compression is not to flip the fame picture, it is more easy to choose an extra delay time till flipping the next frame. --Hans Haase (有问题吗) 12:03, 16 January 2016 (UTC)

I have only used GIMP occasionally, but here's what I remember. When opening or saving GIF files, each GIMP layer is considered a GIF frame. The frame duration is specified in the layer name in parentheses: GIMP Tutorials - Simple Animations shows examples like (1000ms) and (1500ms). Based on that, I intepret the options above to mean:

• If the layer name doesn't specify a duration in parentheses, use this default duration: ____ milliseconds.
• □ Ignore durations specified in the layer names and always use the default duration above.

You can probably do a test to confirm that's how they behave. --Bavi H (talk) 19:31, 16 January 2016 (UTC)

Thanks for the info ! StuRat (talk) 22:04, 18 January 2016 (UTC)

Futuristic font(s)

I'm searching for a 'list' of futuristic fonts for MS Office/Word. Something that actually 'looks' futuristic not just 'entiles' futuristic. What do you guys recommend? -- Mr. Zoot Cig Bunner (talk) 20:00, 16 January 2016 (UTC)

Just try a Google image search for 'futuristic fonts.'--3dcaddy (talk) 20:48, 16 January 2016 (UTC)

Greetings Russell.mo, At website www.dafont.com search for cyber fonts will give a good selection. Regards,  JoeHebda (talk)  17:14, 17 January 2016 (UTC)

Anyway,

3dcaddy: Checked before posting!... Thank you.

JoeHebda: I've bookmarked it. Since its a huge list, I'll look at it hopefully in the near future... Thank you.

Any recommendation guys? For example, something that will never 'go old' or 'die out'. Something that will last even after the death of our solar system...? E.g., the font "Times New Roman" is a goldie - although "Ariel" font is taking a peak for some time/years, Times New Roman font is still posh/graceful/historic/modern...if you know what I mean. I tried using Times New Roman font, but it lacks the 'forward looking' or 'futuristic/future looking' bit, if you know what I mean. -- Mr. Zoot Cig Bunner (talk) 19:04, 18 January 2016 (UTC)

If you want something that will never go old or die out and will last even after the death of our solar system, your best bet is to not write anything and just imagine/dream that you have a font that will last that long (even though we have no reason to think our current alphabet and language will last that long). Nil Einne (talk) 21:17, 18 January 2016 (UTC)

January 17

Difference between ? and * in cron

At work, I have to use a .NET scheduler library that uses Unix cron expressions for scheduling. The documentation tells me that "?" means "any day/month" and "*" means "every day/month". What is the difference between these? Could anyone give a concrete example where "?" and "*" cause different schedules? Or do such conditions even exist? JIP | Talk 20:46, 17 January 2016 (UTC)

I looked in the Solaris, FreeBSD, and Linux cron(8) and crontab(5) man pages, and I don't see any of them ascribing any meaning to a ? wildcard. This seems to be specific to the fakey crontab your specific .NET thing does. -- Finlay McWalterᚠTalk 22:31, 17 January 2016 (UTC)

Indeed; the same applies to GNU mcron; the '?' symbol is not a documented feature of either type of cron syntax supported by the GNU variant. Your best bet is to check the documentation that specifically applies to your scheduler tool or library, because it evidently uses its own variation of the standard syntax. Nimur (talk) 22:57, 17 January 2016 (UTC)

I don't understand it either. Usually a "?" wildcard in a string means any ONE character whereas "*" means any string of characters. Bubba73 ^{You talkin' to me?} 23:30, 17 January 2016 (UTC)

Well, "usually on Windows"... but even then, use caution: '?' and '*' wildcard behavior varies wildly between the ordinary Windows command interpreter, the Windows Power Shell, Windows Power Shell "cmdlets", and third-party programs that run on Windows. Here's an MSDN blog on the difference in wildcard expansion between Windows and unix...; and even that doesn't mention the special case of cron syntax.

For what it's worth, our article on cron mentions that '?' expands differently on nncron, a proprietary freeware variant of cron developed for Windows. It even self-describes its '?' expansion as "non-standard." Nimur (talk) 02:32, 18 January 2016 (UTC)

cron syntax isn't a special case of shell filename globbing. It's a totally different thing. I guess it's possible that shell syntax influenced cron's use of * for "any value", but *2 doesn't mean any value ending in 2, etc. I don't know why Bubba thought there was any connection. -- BenRG (talk) 04:10, 18 January 2016 (UTC)

I thought so because of Wildcard character, but I admit that I don't know anything about cron. Bubba73 ^{You talkin' to me?} 04:47, 18 January 2016 (UTC)

On NetBSD UNIX, the crontab format is explained in crontab(5), i.e. "man 5 crontab", and this version does have a meaning for "?". It means that when reading the crontab file, cron is to select any one value randomly from the permitted ones. So for example "20 ? * * *" specifies that the job is to run once a day at 20 minutes past some hour: for example, it might be at 3:20 or 7:20 or 23:20. "? ? * * *" would run it once a day at a random time. Also, "?" can be followed (without spaces) by a range, which asks for a random selection from that range. "?40-42 * * * *" would run the job once an hour at either 40, 41, or 42 minutes past the hour.

Note that if cron ever rereads the crontab file, a new random selection will be made. So if you edit the crontab file, even if you did not change the entry where "?" was used, then this might cause your "daily" job to switch to a different time, perhaps causing it to execute a second time during the same day/hour/etc. (if it switched to a later time), or not at all one day (if it switched to an earlier time). Similarly if cron had to be restarted for some reason.

The man page points out that this feature is useful if the same crontab entry is used on a large number of machines and would cause each of them to connect to the same host, for example. --76.69.45.64 (talk) 05:26, 18 January 2016 (UTC)

January 18

Travelling with a Google Chromecast

Will a UK-bought Chromecast still have access to UK-licenced content in other countries? Thanks! 94.12.81.251 (talk) 13:46, 18 January 2016 (UTC)

Probably not. Much regional-licenced content filters by IP location. If your chromecast is in e.g. Brazil, it will have a Brazillian IP, and as such you have no clear rights to UK content. SemanticMantis (talk) 17:55, 18 January 2016 (UTC)

In setup, You choose a language. With the YouTube app, possibly the URL of the Video is foreward to the Chromecast when the connection to the adroid phone is establishedy only. --Hans Haase (有问题吗) 20:39, 18 January 2016 (UTC)

As SemanticMantis has hinted at, it would be more useful to ensure your ChromeCast connects via proxy than it would be to buy your Chromecast in the UK. Actually, I strongly suspect it doesn't matter where you buy it. Nil Einne (talk) 21:14, 18 January 2016 (UTC)

Partial specialization on a member class of a class template

I have a (third-party) broken iterator:

template<class T> struct Container {
  struct iterator {/*...*/};
  //...
};

It's broken in that it does not define the typedefs for std::iterator_traits. I can specialize std::iterator_traits myself to supply the correct (and obvious) types, but how? Writing

namespace std {
  template<class T>
  struct iterator_traits<typename Container<T>::iterator> {/*...*/};
}

fails because T is not in a deduced context. Of course, if Container::iterator were a typedef (not a member class), and/or if Container was subject to partial specialization itself, then the compiler might have quite a time determining if each subsequent instantiation of iterator_traits matched the "pattern". But the only simpler way to refer to that nested class than to give the canonical name of its containing class would be to use an alias template, which g++ 4.9.2 rejects on the same grounds. Is it simply impossible to produce such a partial specialization? --Tardis (talk) 17:13, 18 January 2016 (UTC)

I think it's impossible. The top two answers of this question may work for you: either fully specialize iterator_traits for all the contained types that you plan to use, or define an adaptor template with the appropriate typedefs. -- BenRG (talk) 20:00, 18 January 2016 (UTC)

Further searching (based on the idea that this is a general limitation of template deduction) finds the frustrating result that g++ used to do this but stopped to adhere to the standard. It's obvious that—when the nested name is constrained to be the real name of the type—the deduction is technically possible to implement, but the standard simply says no. --Tardis (talk) 00:32, 19 January 2016 (UTC)

NuGet question

My company manages most of its internal projects with NuGet packages. This goes so deep down that different .NET C# class libraries within the same product are referenced with each other through NuGet. So I have found out that if I have to make changes to a library referenced to by other class libraries, I have to first build it, then make and publish a new NuGet package of it, and then update all the references. When I say "publish", I mean we only update our internal NuGet repository. The packages only ever go to our company internally and our customers. But I find it a hassle to go through all this every time I want to modify the code in a class library. Is there an easier way to test the changes, before making an official update? My boss suggested temporarily removing the NuGet reference and replacing it with a direct reference, then undoing all this and putting the NuGet reference back in. But I find this a hassle too. Is there any easier way? JIP | Talk 20:58, 18 January 2016 (UTC)

Does having a phone service reduce available ADSL bandwidth?

My broadband relies on copper telephone wire. Does having telephone service take some of the bandwidth away from the Internet connection? Could I ask for the phone service to be disabled and get slightly faster Internet? --78.148.108.55 (talk) 21:39, 18 January 2016 (UTC)

ADLS and PSTN coexist, they use different frequencies so they don't "use up" each others bandwidth. Vespine (talk) 22:01, 18 January 2016 (UTC)

That's the theory, and is probably true in Edinburgh. In practice, if you are at the end of a six-mile stretch of copper, a phone call can make the ADSL stop working completely (for reasons other than bandwidth). It's worth asking your ISP. Dbfirs 23:00, 18 January 2016 (UTC)

I don't dispute what you're saying (it's common knowledge that ADSL's performance drops rapidly with distance), but this is kind of orthogonal to the original question. ADSL and phone service use different frequencies (the impetus for designing ADSL was to transmit data over existing phone connections by using frequencies above the voiceband frequencies), so disabling the phone service isn't going to add additional bandwidth to the ADSL service. The issue you brought up is interference between phone and ADSL transmissions, but unless you're using the phone, nothing is being transmitted over the phone connection. So, if you don't notice any impact on your ADSL connection when you're using the phone, cancelling the phone service isn't going to improve your ADSL connection. --71.119.131.184 (talk) 00:42, 19 January 2016 (UTC)

January 19

IPv6

It is well-known that the 32-bit IPv4 ran out of addresses. But IPv6 jumps to 128 bits. Wouldn't 64 bits be enough, at least for an extremely long time? That would give each person on Earth more than 2 billion IP addresses. Bubba73 ^{You talkin' to me?} 03:29, 19 January 2016 (UTC)

IPv6 is not designed to be "exhausted". As in, someone gets address 1, followed by address 2, followed by address 3.... etc.... Having a much larger address space allows addressing strategies to be implemented which are not possible with IPv4, this is mentioned here IPv6#Larger_address_space. Vespine (talk) 03:42, 19 January 2016 (UTC)

Yes, but my point is that seems like overkill. Wouldn't 64 bits be enough for a very long time? Bubba73 ^{You talkin' to me?} 03:44, 19 January 2016 (UTC)

It depends on how it's used. Even if every light switch in your house gets it's own IP address, that won't come anywhere near using them all up, but they might use a system that isn't all that efficient as far as assigning every address. For example, the first of the 8 parts might be for the nation, the 2nd part for the state or province, the 3rd for the county, etc., the 4th for the IP provider, the 5th for the institution or business, the 6th for the individual location or homeowner, the 7th for a particular local area network at that location, and the 8th for a device on that network. (I have no idea if this is how they are actually allocated, this is just an example.) So, while this isn't very efficient as far as percentage of IP's used, it is highly efficient at being able to quickly find info, like the IP provider, from the IP address directly. A similar example is a car's VIN, which is longer than it would need to be, if it was a simple serial number. But then, if it was, you couldn't find out much of anything without looking that serial number up in a database. StuRat (talk) 09:25, 19 January 2016 (UTC)

Wait, so this means the final sad end to power-cycling my router to get around paywall article limits? :-) 94.12.81.251 (talk) 11:29, 19 January 2016 (UTC)

Intensive but short programming bootcamps

If I have one month's living expenses as savings, could I learn anything useful at a programming bootcamp in that time? I mean something pretty immersive, where I'd be coding full time instead of working a job. I know some Java already but I'm open to other languages. Location is Edinburgh, Scotland. 94.12.81.251 (talk) 11:34, 19 January 2016 (UTC)