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September 16

Windows 7 logbook?

If you wnated to know what program run in W7 and when, is there a logbook somewhere installed? — Preceding unsigned comment added by W7q (talk • contribs) 12:29, 16 September 2012 (UTC)

There is the event viewer, but I don't think that shows what programs are currently running, only if they have errors. For programs currently running you can use the task manager. Sounds like you want to know program history though, not currently running programs so I'm not sure that is much of a help. Chevymontecarlo 16:19, 16 September 2012 (UTC)

Exactly, I want to know what happened when, but not right now. — Preceding unsigned comment added by W7q (talk • contribs) 16:54, 16 September 2012 (UTC)

buying internet

Just moved into a new house and I want to connect to the internet but no idea how. The last people had some virgin media thing, there's some internet cable sockets under the stairs and a black box with light on wired up to them somehow. So who do I contact to get things organised so I can get internet to my computer, and how do I do so?

82.132.244.35 (talk) 13:56, 16 September 2012 (UTC)

I'd stay away from Virgin Media if I were you, nothing but problems. Put your details into this to see which services are available to you in your area, then call up whichever provider you feel is offering the best service and ask them to install it. 92.233.64.26 (talk) 15:32, 16 September 2012 (UTC)

For the sake of balance, I've had Virgin Media cable broadband dating back when they were still NTL, and have had very few problems with it. --Nicknack009 (talk) 17:06, 16 September 2012 (UTC)

Maybe they were good in the past, but this year however has been awful. Just went down yet again for 2 hours. 92.233.64.26 (talk) 20:46, 17 September 2012 (UTC)

I'd stay away from BT if I were you, nothing but problems... Seriously though, it might be worth asking around (a chance to meet your new neighbours?) to see what the local situation is as far as internet service providers goes. You may find that locally one is much better than another. AndyTheGrump (talk) 15:39, 16 September 2012 (UTC)

Sounds like you might already have a router in place although I can't imagine if someone was moving out they'd just leave the router there and still switched on. Chevymontecarlo 16:14, 16 September 2012 (UTC)

Do a scan and see if there are wlan available. — Preceding unsigned comment added by W7q (talk • contribs) 16:56, 16 September 2012 (UTC)

Uk electricity

having fitted two mini powerline adaptors,in order to link my PC Router to my Tv(in another room)and to discover that it does not work... I refer to an instruction page which informs me that the non -connection may be due to the possibility that I am operating within "different phases of a four-wire three -phase system" How can I confirm this ,is there a way around it176.24.143.105 (talk) 15:30, 16 September 2012 (UTC)

If this is in a residence, your electrical power supply probably is a single-phase supply, not a three phase supply, although because I live outside the UK, I have no clue what they do for such cases as apartment buildings. Check that the adapters are not plugged into power strips or surge protectors because some power strips contain filters that could interfere with the signal. See Power line communication#Home networking (LAN). PleaseStand (talk) 16:46, 16 September 2012 (UTC)

Some houses in the UK have two different phases supplied, but this is usually only if they have off-peak electrical heating installed. If you can see the incoming supply, count the wires: two wires means one phase and three wires means two phases. As PleaseStand mentions above, apartment buildings (blocks of flats) will often have three phases in the building, but only one phase should be supplied to any one flat. The problem is more likely to be interference from nearby "noisy" electrical appliances. You could test out your adaptors by plugging them both into one extension, or by running a temporary extension lead (with care) from one room to the next. If they work in different rooms when plugged into the same socket (via extension), but not when fed from different sockets, then there might be a phase problem, but in that case you should inform an electrician and never use an extension because different phases should never be brought close together. I assume that you have configured the adaptors correctly, so the remaining possibility is that they are faulty. Are you able to try them out with different equipment in a different house? Dbfirs 07:21, 17 September 2012 (UTC)

Android, Linux and Windows security

I have the impression that there are some Android security problems out there, comparable to the Windows problems. But if Android is a kind of Linux, shouldn't it be so secure as Linux? — Preceding unsigned comment added by W7q (talk • contribs) 16:55, 16 September 2012 (UTC)

There's a balance between user-friendliness and security. An operating system that goes right ahead and updates whatever your current app says needs updating is the most user-friendly, as you don't have to worry about all those ugly details. However, this is bad for security, as an app may steer you towards an update you really don't want. You can make a Linux variant behave like Windows, in this respect, but you will then also suffer the consequences. StuRat (talk) 17:10, 16 September 2012 (UTC)

Linux is not inherently any more or less secure than Windows. The system software on both platforms allows a skilled operator to secure their machine and the data it holds from unauthorized access. However, unskilled operators (or skilled malicious operators with a certain minimum level of access) can make any computer system insecure. Linux World News, a reputable Linux news site, provides an archive of recent Linux security news. Microsoft provides a web-page overview of security for end-users. And, here's Google's technical overview of security on Android, geared mostly towards Android programmers. With due respect, it's possible that your impression of security may differ from actual facts about security. This is actually one of the greatest sources of insecurity in modern computer systems: exploitation of people's incorrect information. Nimur (talk) 17:56, 16 September 2012 (UTC)

But how many people are trying to exploit debilities in each system and how many are trying to improve it?

And, if you are running Linux, when all others around you are running Windows, would you be more secure due to incompatibilities of virus, malware?

And what if you are running Microsoft Outlook and Internet Explorer (which is not necessary, but often the case), are you still equally secure?

And does Linux have something as the regarded insecure Windows' Remote procedure call?

That doesn't make Linux 'as such' more secure, but having Linux implies you are more secure. OsmanRF34 (talk) 19:49, 16 September 2012 (UTC)

To proceed meaningfully, we need to define "secure." In fact, most computer security issues I am currently aware of are attributable to user-error: misplaced trust. This type of security hole is technology- and platform-agnostic. For example, consider the popular Mint.com service. Few people consider this to be a "virus" or "malware" of any kind. Yet, the operational principle of the service is that you intentionally authorize a third-party to have access to your bank account. This is terrifically insecure, if by secure, we mean "nobody else may access our bank account." Yet, if "secure" means something else - say, the inability for an unauthorized user to change the system clock (which can impact the ability to authenticate Kerberos tickets), then the use of Mint.com has no impact to computer security. If you don't use Kerberos, you may wonder why administrator privileges are required to set the time: it seems trivial and moot and irrelevant with respect to "security." Yet, by guaranteeing my kerberos tickets are valid, I can assert with confidence that my connection to my financial institution remains secure. If I were to naively trust one of my programmer-friends to reset my system clock, or to otherwise gain certain administrative access to my machine, my confidence in that secure connection would diminish. Nimur (talk) 03:02, 17 September 2012 (UTC)

What you're missing is that while Android is a Linux distro in that it uses the Linux kernel, it is not a GNU/Linux system, which is what the vast majority of distributions known as "Linux" are. Additionally most "Linux" distributions are managed by hundreds to thousands of committed volunteers, whereas Android is managed almost entirely by Google directly. Even if it were the exact same software, the management of a code base is going to be more important than the code base itself. ¦ Reisio (talk) 23:31, 16 September 2012 (UTC)

Playing DVDs on Fedora 17 Linux

I have the entire run of the TV show Monty Python's Flying Circus on box of DVDs that I bought from Amazon.com. I tried to play a DVD on Xine on Fedora 17 Linux, but it reported that it couldn't find a plugin for dvd://. After googling I found out that I had to create a symlink at /dev/dvd pointing to /dev/sr0. This worked, but Xine stopped after the introductory track, claiming it was trying to make an unauthorised access to a scrambled sector. After googling, I found out that I had to install libdvdcss from Livna.org. This worked and allowed me to view the entire DVD. Surely the symlink will now stay in place even if I don't have a DVD disk mounted? It does seem a bit silly that I need to install libdvdcss to view content that I bought fully legally and paid real money for.

After viewing the DVD, I shut down Xine and physically ejected the DVD by pressing the eject button on the DVD drive. However, this left /dev/sr0 mounted to a directory under /run/media, and that directory was inaccessible. (Of course, since the DVD had been ejected.) I ran umount /dev/sr0 which also removed this directory. Was ejecting the DVD by pressing the eject button without unmounting the filesystem or using the eject command fully safe? I can't imagine the contents of the DVD being messed up, because I'm only reading from it, not writing to it. JIP | Talk 18:07, 16 September 2012 (UTC)

Firstly, you can get all these Linux questions answered so much faster at irc.freenode.net. :p
You only have to create a symlink if your program is too dumb to be configured to use /dev/sr0; I don't know xine well but I assume it can be configured to use it (not that linking the two isn't fine). It is silly that many legislative entities feel the right to own something and the right to actually utilize it are two separate things, but as Fedora is tied to an entity that has something to lose and doesn't want to be sued, they separate out the distribution of the decryption software. It does sound like something isn't working perfectly on your system, but things that are automatically mounted with /media in their path are meant to be inserted and removed without oversight. It's been some time, but if you had manually mounted the disc, you might not have even been allowed to have ejected it manually. ¦ Reisio (talk) 23:43, 16 September 2012 (UTC)

All this looks otherwise all OK, but when I rebooted the system, the symlink from /dev/dvd to /dev/sr0 had disappeared. Is there any way I could make it stay there? I could always write a command in .bashrc or something to automatically create it when I open a shell but there's the problem that writing to /dev requires root privileges and I would have to type the root password every time I open a shell. Is there some kind of "execute this script every time the system boots up" script on Linux? JIP | Talk 18:07, 18 September 2012 (UTC)

locate persistent-cd (or find / -iname '*persistent*cd*'), move it elsewhere (~/) and reboot. ¦ Reisio (talk) 19:12, 19 September 2012 (UTC)

That didn't work. locate persistent-cd didn't output anything, and find / iname -'*persitent*cd*' only gave lots of errors about not being able to access some subdirectories of / (I ran it as a normal user). JIP | Talk 17:47, 20 September 2012 (UTC)

Well then you need to get on IRC and talk to people using your same distro, who are familiar with where things are and how they're done. ¦ Reisio (talk) 18:40, 20 September 2012 (UTC)

MS-DOS Browsers

Are there any DOS browsers capable of being used for things like editing Wikipedia, chatting on Facebook, banking online, checking email, and playing Flash games and videos? If not, could one be made? PCHS-NJROTC ^(Messages) 18:21, 16 September 2012 (UTC)

I'm not quite following you. By DOS browser, do you mean a text-based browser, like Gopher (protocol), which, by definition, couldn't play Flash games ? It might be able to do some of those other things, although in a simplified form.

Or perhaps you mean any browser running on Windows ? In that case, they pretty much all support those things. StuRat (talk) 18:24, 16 September 2012 (UTC)

IBM PC compatible computers from the MS-DOS days, predating Windows, could very well use graphics. We used such computers in our elementary school to play games such as the Space Quest series. So it's entirely possible that an MS-DOS browser could play Flash games and videos. However, as I understand it, MS-DOS is largely obsolete these days, and coding such a browser in MS-DOS (without Windows) would be such a great deal of a job that almost no one would be willing to do it. JIP | Talk 18:28, 16 September 2012 (UTC)

I was thinking along the lines of doing this when Windows XP becomes obsolete, since a lot of computers from the early 2000s don't work well with Windows Vista or Windows 7. PCHS-NJROTC ^(Messages) 18:30, 16 September 2012 (UTC)

I've been using obsolete O/S's for a long time (Windows 98). They aren't as bad as you might think. The lack of constant updates actually makes them more stable. You might as well stick with Windows XP. I plan to, on my XP machine. I would generally only risk a new O/S on an entirely new PC. StuRat (talk) 18:37, 16 September 2012 (UTC)

I've put XP on a lot of 98 computers. The first one I did that with XP actually worked a lot better with because XP would increase the size of the page file when it would run out of memory whereas 98 would just give me error messages. But 98s okay, lots of memories with it. PCHS-NJROTC ^(Messages) 18:41, 16 September 2012 (UTC)

So what would be the most someone could do with already existing DOS browsers? PCHS-NJROTC ^(Messages) 18:34, 16 September 2012 (UTC)

By "browser", do you mean "Internet browser" ? It looks like JIP was only talking about running things directly on that PC, not over the Internet. StuRat (talk) 18:35, 16 September 2012 (UTC)

I was under the impression you were under the impression that "MS-DOS" inherently meant "text only", which I demonstrated to be false. MS-DOS can both connect to the Internet and display graphics. However, creating a graphical WWW browser doesn't inherently follow from this. Someone has to code it, and as far as I understand, no such browser for MS-DOS only (not Windows) exists. JIP | Talk 18:39, 16 September 2012 (UTC)

No, I wasn't talking about inherent limitation of MS-DOS, but rather those of an Internet browser running on it. StuRat (talk) 18:50, 16 September 2012 (UTC)

What inherent limitations would those be? As far as I am aware, no graphical WWW browser for MS-DOS, at least one supporting Flash media, exists, but that wouldn't stop someone from creating one, as long as TCP/IP connectivity is available. JIP | Talk 18:53, 16 September 2012 (UTC)

Not an inherent limitation, but one of availability, assuming the OP isn't going to write his own browser. StuRat (talk) 19:02, 16 September 2012 (UTC)

OK, now I understand what you mean. JIP | Talk 19:15, 16 September 2012 (UTC)

Yes, I'm talking about an internet browser. PCHS-NJROTC ^(Messages) 18:36, 16 September 2012 (UTC)

Notoriously, MS-DOS never supplied a TCP/IP API. So by the strictest definition, you could not use "the internet" on a DOS computer - at least, not out of the box. Applications that ran on DOS could provide their own device-drivers for a specific internet connectivity device, and could implement a TCP/IP stack in software (or implement a different networking communication protocol, like the infamous IPX). But, by the time the Internet and the protocols it used became commonplace, Microsoft Windows had supplanted DOS. Here is a (somewhat stale) page from CalTech on programming TCP on DOS. Using modern software, it would be possible to compile, for example, cURL or Lynx for DOS. Lynx is available for OS/2; if you are a skilled programmer, you can grab the Lynx source-code, compile for OS/2, and then attempt to port to a DOS TCP API. Nimur (talk) 18:42, 16 September 2012 (UTC)

And if you can do that, and program graphics output on MS-DOS, you're on your way to creating a graphical WWW browser on MS-DOS. After all, the only difference between a graphical browser and a text-only browser is that a graphical browser can interpret the image files and graphical layout definitions it already received over the Internet via a graphics output device. However, this has to be coded in software, and it's going to be a good deal of work, and interpreting Flash media is going to be even more work. JIP | Talk 18:47, 16 September 2012 (UTC)

Gopher_(protocol)#Gopher_item_types gives you some idea. Web searches, displaying HTML pages or pics, playing audio, etc. At least some email systems, like Gmail, ought to work. StuRat (talk) 18:43, 16 September 2012 (UTC)

What about wi-fi, what would that require? Also, my biggest fear with XP is that because they have that product key thing in it I won't be able to do a fresh XP install after it becomes obsolete. Although I do have a Win 95 CD somewhere, so that might be a better option than DOS, but wouldn't there be more security issues with 95 than DOS (since nobody writes DOS viruses anymore)?

Well, my point is that you won't need a fresh install, unless the hard disk fails, since you won't be constantly updating the XP system and thus getting into trouble. Also, I don't think they can prevent a new install from CDs, although they might very well stop supplying the O/S online.

(ec with Mr.98) Something else you might want to consider is a Linux install. Those are basically designed for people who don't want to be tied to Microsoft. They have browsers that can already do what you want. One downside is that they are often more work to install initially. StuRat (talk) 18:55, 16 September 2012 (UTC)

If your goal is to use old hardware for a very long time, but still want to do modern things, you'd probably be better off switching to some Linux variety. They will combine the no-frills approach that is necessary for old hardware, but will actually have things like modern browsers written for them, updated regularly, and things of that nature. MS-DOS is a particularly lousy place to try and draw one's line in the sand — it's too old for the stuff you want to do. --Mr.98 (talk) 18:57, 16 September 2012 (UTC)

Yup: if you have ancient hardware that won't run Windows beyond XP, why not install Linux of some sort instead? Ubuntu for instance will work well enough for web browsing on some fairly old hardware - I've go 10-year-old Compaq Evo which even though it is technically under-spec for Ubuntu manages to run it, and there are Linux distro's expressly designed to run on low-spec systems. AndyTheGrump (talk) 18:59, 16 September 2012 (UTC)

Linux is an intriguing idea, and that was actually going to be my next question. I know absolutely nothing about Linux, as I've always been a user of Microsoft OSes, but it's sounding interesting. Would it be possible to have a boot menu where you can choose between Linux and Windows at boot (so I could get used to Linux)? And what are the system requirements for Linux, I read somewhere that it can boot from floppy disks, does this mean you could go back as far as the old IBMs and Tandys from the 80s with Linux? PCHS-NJROTC ^(Messages) 19:03, 16 September 2012 (UTC)

Early PCs from IBM used Intel processors prior to the Intel 386. Current main line versions of the Linux kernel do not work on earlier x86 processors such as the 8086 or the 286 in the IBM PS/2 series. Tandy (like the TRS 80 and other Z80 processors are similarly unsupported. This means that the basic functionality of Linux - its kernel - has not been ported to these platforms in any serious fashion. You may find List of Linux supported architectures worth reading. Of course, any Turing-complete computer can run Linux, in a hacked-up software-emulation fashion (for example, emulating a kernel entirely in user mode). But, though Linux has been ported to many systems, certain hardware features are important for realistic performance: memory protection; hardware-assisted preemption; virtual memory. Linux can be modified and compiled without these features, but then we enter into a ship of Theseus-style conundrum: at what point does the code which used to be Linux, but sufficiently modified to provide basic scheduling and device operation for the TRS-80, cease to be Linux, and simply become CP/M, or the Tandy BASIC environment, or whatever else you expect to run on that machine? Nimur (talk) 03:19, 17 September 2012 (UTC)

Linux required a 386 from the start (see Linus's original announcement). To my amazement, there is apparently an 8086 port (ELKS Linux), but I'm not sure how much it has in common with official Linux. -- BenRG (talk) 04:20, 17 September 2012 (UTC)

Yes, it's entirely possible to have a boot menu where you can choose between Linux and Windows at boot. You should do this when installing Linux - installing Windows will probably only create a bootloader for Windows. System requirements for Linux vary widely. For example, the system requirements for Fedora 17 (which I use), at least when using the GNOME graphical desktop, are almost as high as for Windows 7. But there are other distributions with much lower system requirements. Particularly, if you don't install a graphical desktop, but only use Linux in text-only mode, you could basically do it in late-1980s or early-1990s hardware. I think you're still best off using a hard disk though, I don't think even the smallest Linux distributions can fully fit on a floppy disk. JIP | Talk 19:08, 16 September 2012 (UTC)

A dual boot system allows you to boot into either. An alternative is to boot from CD or flash drive (if your computer can boot from flash drive), so you get Linux when the CD or flash drive is in place, but Windows when it's absent. Any Linux system which could boot from floppy disks is probably too bare bones to do what you want. StuRat (talk) 19:07, 16 September 2012 (UTC)

Yes, Arachne (web browser). Well, I don't know if it can do all those things, but it is at least a graphical web browser, for DOS.  Card Zero  (talk) 21:20, 16 September 2012 (UTC)

Some non-Linux systems which may be of interest include ReactOS (the Windows substitute), Syllable Desktop (operating system) (The formerly Amiga ... thing), and FreeDOS if you like DOS. Just because it doesn't have to be about Linux all the time. Though really you want whatever's got all the drivers.  Card Zero  (talk) 21:27, 16 September 2012 (UTC)

To me, all quite pointless except to the most masochistic hobbyist. Why would anyone want to do anything internet related with vanilla DOS when there are many other OS's with drivers that work with old computers? For linux - what about Raspberry Pi? This is an example of what can be done. Sandman30s (talk) 13:50, 17 September 2012 (UTC)

September 17

windows XP serial number and license key

are they the same thing? if not then what is the difference? — Preceding unsigned comment added by 203.116.187.1 (talk) 07:59, 17 September 2012 (UTC)

No, they are not. A serial number is just one in a continuous series. So, if you are 1234567890 then the next poor sap Microsoft customer is 1234567891. That's not good enough for a license key, though, as anyone could guess at a valid number from the range in use. A license key tends to be far longer and randomized, so that you are extremely unlikely to guess one. StuRat (talk) 08:36, 17 September 2012 (UTC)

However, depending on the context they may be the same thing. A lot of people refer to the license key as a serial number, even though the name isn't accurate. The only time I've seen a true serial number (StuRat's definition) on a Microsoft OS is with volume licensing or embedded OSes, and that comes on a simple small sticker, not the big one with the rainbow coloring, bar code and shiny strip. Odds are that if someone is talking about a Windows serial number they actually mean a license key. 209.131.76.183 (talk) 12:59, 17 September 2012 (UTC)

How to disallow others from adding me in groups in Facebook?

In every three or four days someone adds me in a group, as a result my email and notifications get flooded. How to disallow others from adding me in groups? Best, --Tito Dutta ✉ 09:02, 17 September 2012 (UTC)

IIRC the only way you aren't auto-added to a group is if you do not click a single link you get about how one of your friends have joined a group. ¦ Reisio (talk) 16:03, 17 September 2012 (UTC)

I do not click ay link, I have also stopped using Facebook, but in every few days someone adds me in their group and I have to visit Facebook to unjoin or turn off notifications. Regards! --Tito Dutta ✉ 05:39, 19 September 2012 (UTC)

Visiting facebook can re-enable an account that you have disabled (and even one you have asked to have deleted). You have to basically log out of facebook and delete your cookies and not log in for 14 days or something like that. ¦ Reisio (talk) 06:13, 20 September 2012 (UTC)

Strange problem with MediaWiki's edit toolbar.

Was it just me, or is the edit toolbar on my wiki acting a little too wonky? Loading the edit page after clearing the cache, or perhaps on a newly-installed browser, will end up with the toolbox not being able to initialise, but if you open another article on the wiki and edit it, the toolbox options do show up. My hunch is that it may have something to do with either the MediaWiki software, or perhaps my browsers. The symptoms occur on both Firefox and Chrome, and I'm using the latest stable build of MW as well. Blake Gripling (talk) 10:25, 17 September 2012 (UTC)

I do not see any problem with the toolbox in FF. Ruslik_Zero 12:18, 17 September 2012 (UTC)

Apple's Magic Mouse

Pre Lion/Mountain Lion I could awaken my laptop from 'sleep' by just touching the trackpad or simply picking up the Magic Mouse, but now neither of those otions work and I have to push the of/off button. The computer wakes instantly but I much preferred simply to pick up the mouse. Can I this facility back and if so how please.--85.211.199.83 (talk) 15:14, 17 September 2012 (UTC)

Sorry about the stupid errors above, the last 'can' should read 'get'--85.211.199.83 (talk) 15:20, 17 September 2012 (UTC)

I removed your unnecessary use of bold

I'm not a Mac user, but a quick search through the 'Apple Support Communities' suggests you are not alone. It seems to depend on how deeply your laptop has gone to sleep, but more than one suggests changing the hibernatemode setting (I would like to provide more links to threads, but for some reason the "next" link on the search page is broken in Chrome). Astronaut (talk) 17:11, 17 September 2012 (UTC)

Folder 'Temp'

I clicked "Run" option present in "Start menu". "Run Window" appeared and I typed "%temp%" in the search box. A window with title "Temp" came on screen. I deleted all files and folders present in that "Temp Folder". I think all files and folders were useless. Is it correct to say that "Temp Folder" contains useless files and folders? Sunny Singh (DAV) (talk) 17:28, 17 September 2012 (UTC)

Not exactly, it's more correct to say that they are (intended to be) only temporarily useful. ¦ Reisio (talk) 17:31, 17 September 2012 (UTC)

Programs on your computer will often use that folder as a space for files that they only need temporarily. After the task is done, they are supposed to clean up the files themselves. An example could be a program that downloads a large file. It may decide to download the file to the temp directory, so the user doesn't see a partially-downloaded file in their target directory. Once the download is complete, the downloader program can rename and move the file out of the temp directory and into the target directory. The problem is that not all programs are good about cleaning up after themselves, and occasionally a poorly-written program may even decided to store something important in the directory. It is usually harmless to delete everything in the temp folder if there is nothing else running on the system, but it is possible for it to cause unexpected problems. 209.131.76.183 (talk) 18:02, 17 September 2012 (UTC)

Free Trials

Some pieces of software allow a free trial which ends after a fixed period of time. How does the software know that the time is up, and what does it do to stop you downloading it a second time? There must be some kind of analogue of a cookie. I don't like the idea of having hidden files that I can't find, let alone security scan. How could I find these cookie-like files? — Fly by Night (talk) 19:08, 17 September 2012 (UTC)

The people who set up those things go to great lengths to keep people from being able to defeat them. There must, as you say, be some cookie-like thing, but it is likely to be well hidden, and different programs will hide it in different ways. Looie496 (talk) 19:27, 17 September 2012 (UTC)

Early software sometimes just used the system clock, so could be defeated by setting the clock back. However, they are more sophisticated these days. With Internet connectivity, for example, they can either find a standard time and date on the web, or could access their own website, with it's own timer. StuRat (talk) 19:40, 17 September 2012 (UTC)

Thanks for the replies chaps, but I was looking for something more informative. Anyone else? — Fly by Night (talk) 19:48, 17 September 2012 (UTC)

You didn't say which program. 146.90.50.247 (talk) 19:52, 17 September 2012 (UTC)

As far as preventing you from reinstalling the trial version, they can store your I/P address or CPU serial number at their site, and refuse to allow a second trial download from that location again. StuRat (talk) 20:02, 17 September 2012 (UTC)

It's usually a combination of registry keys and checking the system date, AIUI. ¦ Reisio (talk) 19:55, 17 September 2012 (UTC)

Yes, with some current trials you can successfully extend the trial by disconnecting the internet and putting back the system date before running the program, but you've only to make one mistake in running with the current date to be permanently locked out (unless you can find the hidden code that implements the lockout, and it's not as simple as a plain registry key). Dbfirs 20:14, 17 September 2012 (UTC)

Some programs also use files stored somewhere in the Windows directory. Then of course there's Macrovision SafeCast notably used in Adobe programs which hides stuff in absolute sector 32 of your HDD which is normally before the partition start and so won't generally be overwritten even if you delete all partitions and install Windows fresh; without zero filling the beginning of the HD (or intentionally killoing the sector because you know about it). Nil Einne (talk) 05:48, 18 September 2012 (UTC)

Similar to Dbfirs. You can sometimes have success by ensuring that nothing has been left in the registry. CambridgeBayWeather (talk) 17:02, 18 September 2012 (UTC)

Bad blocks on drive, reducing timeout length; why weren't bad blocks marked as bad at write time

I have a few related questions to the same problem. I have a NTFS formatted drive with some bad blocks that stores a backup file that I now need (Murphy's Law). I should note too that these files reside at the end of the drive, an area I almost never use, so preexisting bad blocks that I only now noticed isn't out of the question. The problem isn't so much the sporadic errors in the files (I can deal with some corrupt files); the problem is that when it hits one of these bad blocks the cpu will retry over and over to read it only timing out after about 2 minutes. This makes reading the drive impractical. I'm trying to recover it with dd noconv=error to another drive, but it's also hanging for too long on these bad sectors/blocks. Is there a way (in Linux) I can modify the timeout length to be shorter?

The other problem is that these blocks should have been recently written to, so why didn't either the drive internally, or NTFS, mark them as bad at write time (only a few days ago)? I find it difficult to believe they all went bad within that short timeframe. Or when I do an NTFS format shouldn't it mark these as bad?

I was able to use hdparm's "very dangerous" write to sector tool to force it to remap a few of these, but I can't quickly get a list of all the bad blocks. Is there a good way to do this too (without it taking 2 minutes at each one)? Shadowjams (talk) 21:04, 17 September 2012 (UTC)

For a disk with read errors, I would use ddrescue rather than dd (whether its timeout control will address your issue specifically I don't know). A bunch of related LBAs all going bad in a short time is suggestive (not not indicative, probably) of local contamination. The drive's own remapper, or NTFS, would indeed have marked the blocks bad and remapped them, had they known, so the fact that neither did means they didn't. -- Finlay McWalterჷTalk 21:19, 17 September 2012 (UTC)

duckduckgo not working?

The site duckduckgo provides shortcuts for a faster search. For example g! means google it, d! means search for it in a dictionary. It doesn't work at my side, but I don't know what's happening. OsmanRF34 (talk) 21:41, 17 September 2012 (UTC)

You're putting the exclamation mark on the wrong side of the shortcut; it comes before, not after. Instead of g! and d!, you need to be typing !g and !d. Hope this helps. CalusReyma (talk) 11:12, 18 September 2012 (UTC)

There are called bang keywords and actually have the form !keyword. For example: !g (for google), !w (for wikipedia) and so on. ListCheck (talk) 11:15, 18 September 2012 (UTC)

How odd! I had exactly the same problem yesterday. Paul (Stansifer) 14:41, 18 September 2012 (UTC)

Another method of using shortcuts is available in-program with modern browsers like Firefox. E.g., "w Barack Obama" will take you to Barack Obama immediately. -- 143.85.199.242 (talk) 21:30, 18 September 2012 (UTC)

http://www-archive.mozilla.org/docs/end-user/keywords.html ¦ Reisio (talk) 19:13, 19 September 2012 (UTC)

Understanding clincher at staple

Today, I have bought Kangaro DS- 23S13 QL heavy duty stapler. It has clinch that has two hole for stapling paper that indicates measurement of 6-13 and 8-15. It can be rotated as per number and thickness of papers. The first hole of clinch has number, 6-13 (leg length of staples) on left side (just above the hole). The whole is not plain. And the second hole has 8-15 (leg length of staples) on right side. This hole is plain. I don't understand which number indicates which hole to be used during stapling paper. Right now, from the user eye side, I can see that 8-15 is positioned "Flip vertical" above the right side hole in clinch and 6-13 is positioned normal state (left side of the hole). It's my first time to use this type of stapler. The loading capacity is 100 pages. Can anyone please help me to recognize the number on clinch's hole ? Thanks--180.234.89.110 (talk) 23:33, 17 September 2012 (UTC)

P.S. The capacity of 6-13 is 2 to 100 pages and 8-15 is 25 to 100+ pages (though they say that, up to 100 pages can be stapled in their Brochure).

Here's a picture of the stapler, for anyone who needs it: [1]. StuRat (talk) 23:46, 17 September 2012 (UTC)

I'm having difficulty in parsing your question, with phrases like "hole of clinch" and "whole is not plain" leaving me confused. However, a stapler is a simple enough device, and staples are cheap enough, that you can just experiment with the various settings until you get the desired result. I'd use scrap paper to practice with. BTW, I've always set them so the staples bend inward, as you are less likely to get poked by one that way. Also note that you can sometimes staple a few more sheets if you staple from both sides, offset slightly (although I'd only do this if I didn't have any binder clips handy). StuRat (talk) 23:48, 17 September 2012 (UTC)

• Well, I figured it out. One more thing is that, that staple suddenly fell on the floor from my table. I quickly picked it up and checked whether there is any damage. So far I have not found one. Can it be internally damaged if it falls on the floor? Though it's steel made device but what about the durability?--180.234.239.3 (talk) 00:17, 18 September 2012 (UTC)

• I'm guessing you meant to say that the stapler fell on the floor, not a staple. They are pretty durable, although it might have knocked the currently loaded staples out of position, so you may need to open it up and push them back where they belong. StuRat (talk) 00:30, 18 September 2012 (UTC)

September 18

Clean Python code [APT/Ubuntu]

Hi. So... I have this somewhat simple python program It's function is to display a simple GUI, and if the user clicks in the option "install vlc", it will install vlc. However, I want to completely skip the initial GUI and I am only interested in automatically launching the vlc installation when the script is launched... I assume it is pretty easy, but since I barely know any python... Thanks. --Hacktolive (talk) 02:38, 18 September 2012 (UTC)

Based on the documentation here, I suppose this will work:

    import aptdaemon.client
    aptdaemon.client.AptClient().install_packages(["vlc"])

Untested, though. -- BenRG (talk) 04:59, 18 September 2012 (UTC)

Microsoft Outlook Scroll Bar

Caould you give me any ideas on why my scroll bar on Microsoft Outlook takes off a great rate of speed when I am looking at emails. This has happned a couple of times and I am wondering why.

Many thanks

Ann Johnson — Preceding unsigned comment added by Johnoowen (talk • contribs) 04:28, 18 September 2012 (UTC)

Are you on a laptop with a touchpad? That'd be my 1st guess. Vespine (talk) 05:05, 18 September 2012 (UTC)

Could it be the down arrow on the keyboard sticking down ? StuRat (talk) 05:55, 18 September 2012 (UTC)

If you (like most these days) use an infrared mouse it could be that causing it. My pointer at work randomly moves ocassionally without my mouse moving (at least without me moving the mouse) and sometimes causes Excel to scroll quickly down. I've always put it down to being on an uneven/imperfect surface and the infrared getting confused. ny156uk (talk) 20:23, 18 September 2012 (UTC)

Animated weather radar maps

They always seem to have too few frames, so it looks very "jumpy", whether on the Internet or the TV news. What's the problem ? Why can't they capture enough frames to make for a smooth animation ? StuRat (talk) 06:23, 18 September 2012 (UTC)

Weather satellites do not shoot video at 30 frames per second, as standard video is. There is no need, the weather doesn't change that fast. I do not know the exact frame rate, but from watching satellite video, my estimate is about a frame per minute.    → Michael J Ⓣ Ⓒ Ⓜ 07:25, 18 September 2012 (UTC)

Weather satellites, like those in our GOES fleet, are not the source of weather RADAR imagery. You can see a full listing of GOES' data products here: GOES Products and Services; or peruse the main website at http://www.goes.noaa.gov/ . Nimur (talk) 14:55, 18 September 2012 (UTC)

I suspect that's even too high. The animations at weatherspark.com are a frame every five minutes, and look like "standard" framerates to me. --Mr.98 (talk) 14:29, 18 September 2012 (UTC)

Now, how many frames they would need to make it look smooth depends on the magnification level. For a map showing the entire Atlantic Ocean, say to watch a hurricane develop, probably one frame an hour would look smooth. On the other hand, a map of the weather in a town might need one frame per minute to smoothly show how a storm is moving through the area. These frames are then sped up, of course, for display, say to 30 frames per second. This would make the hurricane tracking for a week take about 6 seconds to play, and the storm moving through a town might take 6 seconds to show the last 3 hours. StuRat (talk) 15:09, 18 September 2012 (UTC)

I guess because ground based weather radar has to gather height information as well as distance, so they use a series of elevation angles, which takes time to complete (5 to 10 minutes max according to the article). Satellite radar would face the same problem, having to scan the surface in a series of consecutive lines.

For ground based radar images there's also the task of combining data from all stations into one global map. Ssscienccce (talk) 08:06, 18 September 2012 (UTC)

A doppler radar unit only scans a straight line, so they have to rotate it to capture the full image. You'll see this when they show the live radar - the line rotates around the location of the radar dish, updating the image as it scans. 209.131.76.183 (talk) 11:46, 18 September 2012 (UTC)

Googling around, I don't see any inherent reasons why it couldn't be done; it would just require optimizing the equipment to that outcome, and probably require new equipment. I doubt they are downgrading the frame rate from what the data is giving them; it probably just doesn't sample data at higher rates than that. --Mr.98 (talk) 14:29, 18 September 2012 (UTC)

Most weather RADAR you see in the United States comes from the National Weather Service's nationwide network of WSR-88D doppler RADARs. The "88" indicates technology from 1988. There have been many many upgrades to the system, but the core RADAR is actually very old. Many experts predict a next generation of RADARs will be available in the near future; here is one page from NOAA: RADAR improvements... Of course, to get a nationwide upgrade, the cost has to be justified and budgeted. StuRat, you may also be interested in NOAA RIDGE2, which is how I always watch RADAR. It is fed from the same doppler transmitters, but displays a configurable data product, including the new 1x1km super-resolution. Here's a link for RIDGE2 near Palo Alto Airport. You might also find DUATS useful: it is a telephone- and internet-enabled user interface for weather and flight planning, organized by the FAA. Again, its RADAR feed is still the same NEXRAD network; but there are additional features and advanced data products available. Nimur (talk) 14:46, 18 September 2012 (UTC)

Thanks. I looked at the RIDGE2 site. It seems to provide a map of current weather, updating every 5 minutes. I saw options for loop speed (slow, medium, fast), but didn't actually see an option to play it in a loop. Am I missing something ? Also, in my experience, the "slow, medium, fast" choices don't change the number of frames, but just how long they hold each frame on the screen. So, no matter what speed you pick, it still looks jumpy. They also have an "Update now" button. I'm not sure what this does. I doubt if it actually displays a map generated that second. Perhaps it just means "display the most recent map we have, of the selected type", which, of course, could be quite old.

As for DUATS, it looks like only pilots are allowed to use that system. StuRat (talk) 15:01, 18 September 2012 (UTC)

RIDGE is a user-interface - "(Radar Integrated Display with Geospatial Elements)" - to various RADAR products. It lets you feed in different RADAR data, and integrates it into a "map" display. If you want access to raw data products, so you can design your own user interface, you might find NOAA's Radar Product Central Collection Dissemination Service useful. Depending on the level of access you need, many of the interesting data is available free of charge. Here is a very high-level overview of some different types of data that you can view. Nimur (talk) 20:36, 18 September 2012 (UTC)

Are there any options for increasing the number of frames (reducing the interval between frames below 5 minutes or increasing the total time in the loop) ? A total of 10 frames is bound to look jumpy. StuRat (talk) 22:04, 18 September 2012 (UTC)

Right above the loop speed option is an option to turn looping on and off. It looks like it loops 45 minutes at 5 minute intervals. I don't see a way to cover a longer period. 209.131.76.183 (talk) 17:20, 18 September 2012 (UTC)

Thanks. I had tried that, with no visible results. Apparently I just had to let it wait longer, to build the animation, before it would display. StuRat (talk) 22:02, 18 September 2012 (UTC)

This is one of those areas where the NATIONAL Weather Service could provide a better service to the public if the public were willing to give it more money. (Comment from a past employee of another country's national weather service.) HiLo48 (talk) 17:40, 19 September 2012 (UTC)

Screencasting software

Hi, I'm looking for a decent, free, screencasting program. I've checked out our article, and I'm really just inundated with options. Is there a general favourite of the "typical" consumer, ie. the one who wants a few simple features for doing a Youtube video to instruct people on something (in my case, an app I'm designing)? t.i.a. IBE (talk) 18:20, 18 September 2012 (UTC)

I've used CamStudio, it's a little buggy but the best of all the ones I tried. VLC comes second place but it has no advanced options - you can only record the entire screen, not specific windows or parts of the screen. 92.233.64.26 (talk) 19:48, 18 September 2012 (UTC)

Thanks - has anyone tried Screenpresso? That's the other one I'm thinking of - or I might try both, since I suspect it's easy enough to learn software like this. IBE (talk) 20:03, 18 September 2012 (UTC)

I spend ages trying out different ones for producing in-house training videos. The main problem that I found with CamStudio is that the video produced was in it's own format and I couldn't covert it to anything "sensible" such as mp4 or flash. The converted files just played the initial opening frame for the entire length of the video, or were distorted in all sorts of strange ways. The one that I had the most success with was Wink (tutorial software). This produces flash as the output, you can capture either individual frames (a series of screen shots), or it can capture continuously or it will capture if an event occurs eg pressing a key or clicking the mouse. You can mix all three within the same video. Frames can be annotated with arrows, circles around areas, etc. Narration can be added afterward, which worked especially well when a there was a series of screen shots. There are too many "tutorial videos" on youtube containing (for example) "err umm, I'm just err umm err logging in and errr...." and feature wild random mouse movements. It's damn hard to get a perfect run doing a screen capture and doubly so if you are trying to record narration at the same time. --TrogWoolley (talk) 21:16, 18 September 2012 (UTC)

I think the eyes have it *wink* IBE (talk) 21:52, 18 September 2012 (UTC)

I use Camtasia Recorder

September 19

Trip planning software

I'm organising a trip to about 10 or so cities in one country. I'd like to use something like Google maps to show lines between each city to better visualise distances and surrounding places and sights. Most transfers between cities are by air, some are by road. Can Google maps do that? (I cant see how to draw as-the-crow-fly-lines between places, mixed with road lines). Is there something (free would be nice) that can do this? Moondyne (talk) 06:44, 19 September 2012 (UTC)

If you can't find anything, I suggest you print out Google maps with driving routes marked and just draw the airplane routes in with a marker. (You can also do this online, by doing a screen grab and using MS Paint, if on Windows.) I make this type of "mix and match" maps all the time. Also note that, while plane routes aren't always the shortest possible route (great circles), you can still simplify the routes as lines drawn directly between each pair of cities. StuRat (talk) 06:52, 19 September 2012 (UTC)

You can do this (at least, the measuring-distances-in-straight-lines bit) in Google Maps itself. In the bottom left corner of the map, next to the scale marker, there is a (rather small) picture of a ruler. Clicking it opens the 'Distance Measurement Tool'. You can click two or more points on the map to get a straight-line distance between them, and choose from a variety of more or less helpful units, from metres and miles to American Football pitches, Angstroms and Beard-seconds. - Cucumber Mike (talk) 09:31, 19 September 2012 (UTC)

Could you not use the "Directions" tab in Google Earth? Would Driving Directions for Google Maps be of any use? CambridgeBayWeather (talk) 14:06, 19 September 2012 (UTC)

Thanks for your help. I just figured out how to drive Google My Maps which is exactly what I wanted. Moondyne (talk) 15:23, 19 September 2012 (UTC)

Good, I'll mark this resolved. StuRat (talk) 02:05, 20 September 2012 (UTC)

Resolved

Laptop

Are any ultrabooks equivalent to the Macbook air?138.37.108.16 (talk) 09:50, 19 September 2012 (UTC)

Yes. Shadowjams (talk) 11:00, 19 September 2012 (UTC)

Obvious implied followup: which ones? --Mr.98 (talk) 11:52, 19 September 2012 (UTC)

I know Asus has one: http://usa.asus.com/Notebooks/Superior_Mobility/ASUS_ZENBOOK_UX31E/#specifications http://www.apple.com/macbookair/specs.html. Unfortunately the price isn't that different, as is usually the case with hardware equivalent to Apple computers but not actually sold by Apple. ¦ Reisio (talk) 19:19, 19 September 2012 (UTC)

Depends on what your equivalence function is. Check out the article on ultrabooks. And go nuts with your favorite web search engine: ultrabook editor's choice, ultrabook review, ultrabook comparison, etc. You want gaming/business/FullHD/what - ultrabook gaming, etc. Go to amazon.com and other retailers and look at their lists of best sellers, top rated, new and upcoming models. 88.112.47.131 (talk) 14:31, 19 September 2012 (UTC)

No non-Apple product is really equivalent to any Mac, because only Apple products run Apple's operating system. Looie496 (talk) 17:59, 19 September 2012 (UTC)

Stupid comments like that make me lose the will to live. --Tagishsimon (talk) 18:55, 19 September 2012 (UTC)

Why? Apart from pedantic quibbling (maybe a hacker can get a copy of MacOS-X illegally to run on an UltraBook, but that is unsupported and unlikely to appeal to most users), it is true. The ability to run a fully-supported UNIX on decent hardware is a major reason for the success of MacBooks among e.g. academic researchers. Similarly, the iLife/iWork suites may push many more mundane users to a Mac. A Windows platform is not equivalent, and Linux, sadly, still is a minority choice, and may be tricky to install on cutting-edge notebooks. --Stephan Schulz (talk) 19:03, 19 September 2012 (UTC)

No… possibly (in the extreme minority) the ability to run a fully supported Unix on incredibly trendy and expensive hardware is a major reason. :p ¦ Reisio (talk) 19:15, 19 September 2012 (UTC)

It's a reasonable assumption that the OP knows that IOS only runs on Macs. Ultrabooks that run other OS are equivalent in form factor and functionality. Do you really want an explanation of why fan-boi pedantry does not benefit the RD? --Tagishsimon (talk) 19:08, 19 September 2012 (UTC)

Fan-boi pedantry???!! I actually have a pretty intense dislike for Apple, dating back over twenty years. But it's simply a fact that the main reason people buy Macintoshes is the unity and simplicity of the gui, and no other system provides a comparable environment. Looie496 (talk) 20:22, 19 September 2012 (UTC)

And here I thought they bought them because they were shiny trendy status symbols. :p ¦ Reisio (talk) 06:25, 20 September 2012 (UTC)

http://www.pca.state.mn.us/

At the moment in the German language Wikipedia there's an ongoing effort to repair broken links in some 300,000 articles. And pages on the website above pop up frequently. However, according to Google as well as according to http://mn.gov that is the valid location of the Minnesota Pollution Control Agency. But we cannot reach any page within this subdomain (though several other subdomains including http://dnr.state.ms.us we can connect to). Could one of you within the U.S. please check if the site does not reply also for IPs geolocated within the U.S.? TIA. --Matthiasb (talk) 11:29, 19 September 2012 (UTC)

It works here in the UK. HostTracker indicates the site is working from every country it tested from 92.233.64.26 (talk) 11:49, 19 September 2012 (UTC)

& here on the east coast of the USA; http://www.isup.me/www.pca.state.mn.us ¦ Reisio (talk) 19:21, 19 September 2012 (UTC)

Making columns uncopyable in Excel

I have Excel 2007 and I have to copy and paste certain rows to different spreadsheets, but some of the information is cosmetic on the workbook and I don't need it. So, I want to just be able to highlight Row C, copy it but not have the information beyond lets say Column V to be copied. Is that something I can do? I thought there was like a break function but I can't remember for the life of me what it is and I can't look for it because I don't know what its called. Thanks! Livewireo (talk) 16:47, 19 September 2012 (UTC)

Instead of selecting the row, you can select specific cells for copying. Click in one cell, hold down shift and click in another cell and Excel will highlight a range of cells to be copied. Click in one cell and while the mouse button is still held down, drag to another cell to select a range of cells. Or you can click in one cell, hold down ctrl and click in another cells to create a disconnected range of cells to be copied.

Alternatively, carry on copying the way you have and then delete or clear the things you don't want once you have pasted them in their destination. Astronaut (talk) 18:46, 19 September 2012 (UTC)

I am familiar with these ways to copy cells, I was just hoping there was something easier. I have a lot of hidden columns that have unneeded data for the spreadsheet I am copying things to, and trying to move things around is just a big hassle. I appreciate the help anyway. Livewireo (talk) 19:28, 19 September 2012 (UTC)

If there's no other way, you could put together a set of formulii in a second workbook to pull the data you want into it; and then copy and paste-special/values into the new spreadsheet. --Tagishsimon (talk) 20:00, 19 September 2012 (UTC)

I would put a blank cell at the point where I wanted to stop copying. Then go to column A, hit End then shift-RightArrow and you've highlighted the cells you want to copy. Copy and paste.--Phil Holmes (talk) 15:43, 20 September 2012 (UTC)

Is GNU an OS?

Isn't it a little bit forced to call it an OS like in the article linked above? Common packages like findutils, gzip, grep are simply applications and the most important thing, the kernel, is not part of it. OsmanRF34 (talk) 22:57, 19 September 2012 (UTC)

Actually, GNU has a kernel, namely GNU Hurd. It's more often used with Linux, of course. Anyways, all UNIXes are mostly bundles of applications, configuration files, and libraries. The kernel is a fairly small part. --Stephan Schulz (talk) 23:04, 19 September 2012 (UTC)

Yes, the kernel is quite small, but essential. I tend to think kernel = OS, and even if GNU Hurd is also = OS, GNU packages are apps. OsmanRF34 (talk) 23:09, 19 September 2012 (UTC)

Well, the standard definition of an OS is given in our article: "An operating system (OS) is a collection of software...". It's not just the kernel. Note that a normal UNIX system cannot really be used (or even booted) without a large collection of what you call "apps". The startup scripts require a Bourne shell to execute, and use all kinds of UNIX commands, nearly all of which are (or at least used to be) independent programs. And if you interact with the OS, you need shell, terminal emulator, passwd, and plenty of other programs. --Stephan Schulz (talk) 23:27, 19 September 2012 (UTC)

The original plan of the GNU project was to create an operating system, but they bogged down, and never managed to create a kernel that was good enough to be widely adopted. They created much of the rest of what is needed for an OS, though. Looie496 (talk) 00:16, 20 September 2012 (UTC)

What Stephan said. ¦ Reisio (talk) 06:31, 20 September 2012 (UTC)

September 20

Will iOS 5.1.1 -> iOS 6 upgrade strip all my apps and make me manually reinstall them?

That's my question. Thanks. 67.163.109.173 (talk) 03:19, 20 September 2012 (UTC)

Nope. Just did it myself. Hot Stop (Edits) 03:22, 20 September 2012 (UTC)

Although when carrying out any major upgrade such as this, you should assume that 'bad things will happen'(TM) and that all your documents, files, pictures, apps and settings will disappear into the black hole of computing misery. Do a backup just in case so you can restore them if/when it happens. But as Hot Stop says, you should be fine. - Cucumber Mike (talk) 09:51, 20 September 2012 (UTC)

I just asked because this happened when I upgraded to 5, and apparently to many others on that upgrade, judging by the number of articles giving instructions on how to recover them, which I did then. 67.163.109.173 (talk) 12:27, 20 September 2012 (UTC)

Interesting. It didn't happen to me (it remembered everything -- safari history, passwords, etc.) when I just updated to iOS 6. But when I updated my blackberry OS a few years back, it wiped out everything. So I guess it wouldn't be bad to backup everything, especially since iTunes does it automatically. Hot Stop (Edits) 12:47, 20 September 2012 (UTC)

I have heard that the upgrade in question makes the Apple-made YouTube app, the one with the retro TV icon, disappear, and replaces the maps app that is powered by Google Maps with a maps app that is receiving a majority of reviews that calls it inferior to the one that will get replaced if this upgrade is done. 20.137.18.53 (talk) 12:55, 21 September 2012 (UTC)

Learning Java

Hi all. I am currently working my way through my first book on Java and feel like seeing more code would be beneficial. Are there any resources on the web that provide examples of working programs that I could look at, just to help me get a better feel for Java? Thanks. 213.123.215.234 (talk) 12:58, 20 September 2012 (UTC)

Sure, lots of sites, search the web for things like java examples and java tutorial. If you want to take a peek at real applications, there are e.g. Apache projects in Java and sourceforge. 88.112.47.131 (talk) 13:21, 20 September 2012 (UTC)

Variable within a python loop

When I write a loop, like:

for i in mylist:
...a += mylist[i]
...b *= mylist[i]
...print(a)
...print(b)

Do I always have to declare variables a and b beforehand? Or is there any more elegant form of doing that? OsmanRF34 (talk) 16:12, 20 September 2012 (UTC)

The accepted "pythonic" way of doing it is to declare the starting values of a and b beforehand, outside the loop. While you can have internal testing for the existance of a and b using try/except [2] [3], in no way would I classify it as "elegant". - By the way, if things like summing or multiplying a list of values is what you want to do, the more elegant way would likely be using something like list comprehensions [4] or various builtins like sum(), map(), reduce() and zip() functions [5]:

a_sum = sum(mylist)
b_prod = reduce(lambda x, y: x*y, mylist)
import operator
b_prod2 = reduce(operator.mul, mylist)

If you really need all the intermediate results, there are ways of doing it, but none really are more elegant than the loop with the starting values specified. -- 205.175.124.30 (talk) 18:35, 20 September 2012 (UTC)

Constructor Calls in Java

In my book on Java, it says "To call one constructor of a class from another of the same class, you can use the this keyword followed by parentheses containing the constructor arguments.". I am confused as to why you do not need to name the constructor you wish to call. Does this apply exclusively to overloaded constructors? Thanks. 213.123.215.234 (talk) 16:12, 20 September 2012 (UTC)

If you have a class Parent that has a constructor Parent(int n), in a subclass Child you can have a constructor that calls the Parent(int n) constructor. The syntax is simply "this(10);". You don't need to name the call because there is nothing to name - you can only call Parent's constructors from Child. I suppose they could have made the syntax "Parent(10);" instead of "this(10);" - but they didn't.

(By the way, if you want to discuss Java and ask about it, check out Oracle's Java forums. Lots of Java knowledge there. Now that Oracle owns Java, that's kind of the "official" forum.) 88.112.47.131 (talk) 16:55, 20 September 2012 (UTC)

Note also that the call to the overloaded constructor (in this case this(10);) must be the first thing you do in the constructor. If you do anything else before it, it will fail to compile. Don't ask me why, but that's the way the language is designed. JIP | Talk 17:44, 20 September 2012 (UTC)

So that it's safe to assume that you start with an completely uninitialies object when a constructor starts. Taemyr (talk) 13:28, 21 September 2012 (UTC)

Battery Voltage

I have an Asus Eee PC 1015PX netbook. The battery that came with it was a 3-cell 11.1V 2100mA battery. I bought a "genuine" Asus battery from a reputable dealer on eBay, it was a 6-cell 10.8V 4400mA battery. I tried it in my netbook and it seems to work fine, but is it a problem that the voltage is different? Thanks.Acceptable (talk) 18:42, 20 September 2012 (UTC)

A less than 3% voltage difference, and it works. The answer is a QED yes. IIRC battery voltages dip as they run out of spunk, and power regulators in consumer electronics handle this well (within limits). And you've got a whole lot more amp-hours. All looks good. --Tagishsimon (talk) 23:43, 20 September 2012 (UTC)

Powerpoint

I know very little about powerpoint - which I am using (ppt 2003 on XP) to generate some slides. I would like to make it so that the default text size is 20pt. It always inserts at 18pt. How do I change this please? -- SGBailey (talk) 22:16, 20 September 2012 (UTC)

View / Master / Slide Master ... set your format preferences, exit, done. --Tagishsimon (talk) 22:34, 20 September 2012 (UTC)

Thanks

September 21

What algorithm or method is used to split color and bw?

To pick just one example, there's a movie called Pleasantville where this happens a lot. There will be a scene where everything is black and white except for one person in color and they are moving around and the color edges of their body against the black and white everything-else are crisply defined. From that article, I saw "The black-and-white meets color world portrayed in the movie was filmed entirely in color and selectively desaturated and contrast adjusted digitally." I want to know the nitty-gritty details of that " selectively desaturated and contrast adjusted digitally." I read the Spirit DataCine article but didn't see an answer to my specific question there. What algorithm can keep track of all the edges of something like a human in a complex moving sequence of frames? 20.137.18.53 (talk) 13:06, 21 September 2012 (UTC)