Wikipedia:Reference desk/Archives/Computing/2011 September 14

= September 14 =

Cable TV
Sometimes in some channels there is an ephemeral appearance of an alphanumeric code.There is no set top box.What is this?Have other people noticed this in their colour television sets with CRT picture tube?Pachyobs (talk) 05:42, 14 September 2011 (UTC)


 * It would be helpful if you told us what equipment you do have and which country it is in. Astronaut (talk) 09:22, 14 September 2011 (UTC)


 * Yes, you have to describe when and where this code appears, and give some examples. One possibility is that it's the serial number (or whatever they call it) which appears at the start of each episode of a TV show.  They don't intend to broadcast this, as it's only for internal identification purposes, but they do occasionally screw up. StuRat (talk) 21:15, 14 September 2011 (UTC)

Hard Drives
What about if the Yellow light problem is fixed on that particular PS3 by an indepenent console repair shop? Not a new PS3 (or refurb) but the same PS3 with the same HDD still intact?--213.107.74.132 (talk) 08:28, 14 September 2011 (UTC)
 * You'll be far better off asking your nearest independent console repair shop. The outcome of repairs will depend on what facilities the shop has and what the precise fault is.  Most shops will be happy to explain their services, and may give a free quotation for repairs. --Colapeninsula (talk) 11:38, 14 September 2011 (UTC)


 * Quote

The outcome of repairs will depend on what facilities the shop has and what the precise fault is.
 * But will you lose what's on the HDD if it gets the YLOD?--213.107.74.132 (talk) 16:10, 14 September 2011 (UTC)


 * It will depend on the repair shop and the exact cause of the yellow light. Do you really think that someone here has the PS3 you are talking about sitting in their lap and can provide a clear answer - of course not. You're just trolling. -- k a i n a w &trade; 16:14, 14 September 2011 (UTC)


 * To go in to more specifics, our article mentions the content is encrypted. It's not mentioned where the encryption key/s are stored. If the encryption key/s are spared and the shop don't wipe the disk (and as you said, the PS3 is returned with the same HDD which I presume means the HDD was not defective) and the PS3 doesn't have some sort of security where it refuses to read/decrypt the disk because it detects something has been changed then your data should be fine. If you want to know more on the probability of this happening for general interest, you'll have to look in to each of these elements (e.g. where is the encryption key/s stored, does the PS3 have some sort of security where it refuses to decrypt the data if it detects something has been modified etc). If you want to know for a specific case, your best bet is asking whichever shop's you're looking in to. Note that some shops may wipe the HDD as a matter of course or at least make no attempt to spare the data so you will have to discuss it with them if this is a real world case. BTW, relying on any single device to store your data is an incredibly bad idea, even more so for a hard disk. In other words, you should not be concerned about the YLOD and your data because of what may happen in the future since if you don't have any problems now, you'll want to look in to some sort of backup solution before you have problems not worry about how you will recover your data if your PS3 dies. If the PS3 doesn't provide any sort of backup option, don't use it to store files you don't want to lose. Nil Einne (talk) 20:53, 14 September 2011 (UTC)
 * What about game saves that cannot be copied to USB?--213.107.74.132 (talk) 08:46, 15 September 2011 (UTC)
 * If the PS3 doesn't provide any sort of backup option, don't use it to store files you don't want to lose. Either don't play games that don't allow their saves to be stored in another location (whether USB or online or whatever) or just don't even bother to use a computer which restricts your ability to copy your content for backup purposes. (From some earlier searches there may be some complicated ways to disable encryption which would probably mean you can copy the content out for backup purposes but from what I read it's the sort of thing you shouldn't try if you have to ask.) Nil Einne (talk) 13:30, 15 September 2011 (UTC)


 * What if you don't even own a PS3 and you just overheard someone mention the Yellow Light of Death and you are supposed to be in lecture at Denbigh, but instead you just feel like being a dick and trolling the Wikipedia reference desk and you still want someone to answer a question that has been thoroughly explained as being unanswerable? -- k a i n a w &trade; 13:56, 15 September 2011 (UTC)

Disks the same?
I heard long ago that the installation CDs for Windows XP were identical, you could therefore reinstall XP Home on a Dell PC using the XP Home product key off the Certificate of Authenticity (CoA) attached to the PC, but using the XP Professional installation CD from your other Dell PC.

Is the same true of Windows 7 installation disks? ie. can I reinstall Win 7 Home Premium on a Dell PC using the Win 7 Home Premium product key off the CoA attached to the PC, but using the Win 7 Professional installation DVD from my other Dell PC? Astronaut (talk) 09:21, 14 September 2011 (UTC)
 * No one knows or has any insight? I'm surprised.  Astronaut (talk) 08:43, 15 September 2011 (UTC)
 * I do know that any particular flavor of Windows installation disk will be identical. SO you can use any Windows Home disk, or any Windows Pro disk. I've never personally tried installing using a different type of disk than I have the license for, but I have heard secondhand reports that it can be successful. I also know that things will go wrong if I use my Alienware disk on a regular computer, things get strange with the installation, but I believe that has more to do with the included drivers. Caltsar (talk) 14:38, 15 September 2011 (UTC)

Flash drives are going to replace traditional hard drives in about 3 years?
I was in my computer class yesterday and the professor said that flash drives are going to replace the old traditional hard disk drives in 2-3 years. Is this true? Have they worked out all of the flaws detailed here (http://en.wikipedia.org/wiki/Flash_memory#Limitations) yet? ScienceApe (talk) 13:32, 14 September 2011 (UTC)


 * That's just his guess, my guess it will take longer than that simply because of the constricts of price vs storage. --Cameron Scott (talk) 13:34, 14 September 2011 (UTC)
 * Have the flaws been addressed? ScienceApe (talk) 14:12, 14 September 2011 (UTC)
 * I'm assuming he meant SSDs, since (at least to me) "flash drive" is a USB drive/thumb drive. KyuubiSeal (talk) 14:31, 14 September 2011 (UTC)


 * It isn't as much a "flaw" as a "design". They are handled by increased speed and size. For example, if I know I have to do two writes for every write request, I just make my writes happen twice as fast and everyone is happy. If I know that my drive will wear out after 10,000 writes but I am expected to handle 100,000 writes, I just load it up with 10 times the memory required. Then, I do 10,000 writes to each one until I've done 100,000 writes in total. Everyone is happy. -- k a i n a w &trade; 14:42, 14 September 2011 (UTC)
 * So isn't the article calling those things "limitations" kind of misleading then? ScienceApe (talk) 14:52, 14 September 2011 (UTC)


 * No. "Limitations" does not mean "flaws". Cars can't drive underwater, and submarines can't go on the road. These are limitations, imposed by their design and their intended use. They are not "flaws".  Your initial question, about whether one kind of storage will replace the other, is essentially a matter of when, or whether, the two technologies will converge. It may be that they will, or that flash will surpass hard disks (as removable optical media has essentially surpassed removable magnetic media).  But there's no reason to think that this convergence is inevitable, and it's impossible to guess when it might happen. Just like a convergence between cars and submarines. -- Finlay McWalterჷTalk 14:59, 14 September 2011 (UTC)
 * Lol well yeah but our articles on cars and subs don't have a limitations section saying that they can't fly. I dono, it's a bit misleading to dumb people like me. :) ScienceApe (talk) 15:34, 14 September 2011 (UTC)


 * I think that is because people tend to know that cars cannot fly, but most people hear "drive" for a computer and assume that all drives are basically the same thing. -- k a i n a w &trade; 15:37, 14 September 2011 (UTC)


 * Who knows about the exact year, Your teacher is either guessing, or quoting someone who was guessing. But eventually?  I'd bet it'll replace spinning-disk hard-drives in most applications.  Already many portable devices work that way. Flash memory has some limitations, but traditional drives have other limitations and problems that can be just as infuriating.
 * The real driving factor is cost. A quick check of NewEgg tells me that $100 will get me 30gb of flash, or 1.5tb of traditional drive. APL (talk) 06:15, 15 September 2011 (UTC)

What format should I save a C.V. as to make it compatible with XP?
Yo. Someone cant read a CV I emailed them, and has asked for it in a format that's compatible with XP. It was sent in a format with the suffix .docx The document was written with Microsoft Word 2007, and saved in the default format. Many thanks in advance. Willy turner (talk) 14:17, 14 September 2011 (UTC)
 * They probably want a .doc file, which is word 2003 compatible. - Q Chris (talk) 14:19, 14 September 2011 (UTC)


 * I know you aren't in the position to say so, but the person can open a docx file. The person just doesn't realize that he or she should install updates. Both Office XP and the free things like OpenOffice or LibreOffice can open docx files if the updates are installed. -- k a i n a w &trade; 14:22, 14 September 2011 (UTC)


 * Ok well if it's correct that they want a .doc file, what is that format called in the list of options? I apologise for my near absolute ignorance of computer-related things Willy turner (talk) 14:39, 14 September 2011 (UTC)


 * Click on file - then Save as - and select the file type "word 97-2003 document" - otherwise, if you want to send people copies that they can read but not alter check if 'PDF' is available in there. --Cameron Scott (talk) 14:55, 14 September 2011 (UTC)


 * A million thanks everybody. Willy turner (talk) 15:03, 14 September 2011 (UTC)

RAM
Does the page file contribute to the 4GB RAM limit on Windows 32-bit computers? Or could I set a 20GB page file and it would work? 82.43.90.142 (talk) 14:51, 14 September 2011 (UTC)


 * It's not taken up from RAM, so you can set it to 20GB, if you like, provided you have that much disk space free (or if you have it page to something else, like a flash drive, make sure it can handle that size). StuRat (talk) 21:10, 14 September 2011 (UTC)


 * No, it will not remove the 4GB limit. 32-bit programs can only access 2^32 addresses, which comes out to 4GB. Adding a 20GB pagefile to 4GB of physical memory is like putting in 24Gb worth of physical memory in the first place, the system will not recognize it. Anonymous.translator (talk) 23:03, 14 September 2011 (UTC)

hmm, two conflicting answers. Anyone have a source? 82.43.90.142 (talk) 00:06, 15 September 2011 (UTC)


 * We've each interpreted your question differently. I thought you were asking if paging space is subtracted from the available RAM.  Anon thought you were asking if paging space allows you to go beyond the 4GB limit for the amount of memory your program uses.  So, both answers are correct, they are just answers to different questions.  (The words "contribute to" seems to be the point of confusion.  If you meant it the way Anon took it, perhaps "ease the restriction on" would have been clearer.) StuRat (talk) 00:22, 15 September 2011 (UTC)


 * I'm confused now. I'm asking if you could allocate 20GB of page file. If you installed 20GB of actual RAM, 32-bit Windows would only see 4GB of it. Does the same limit apply to the page file? Obviously each individual program could still only use 4GB each. Sorry if I wasn't clear 82.43.90.142 (talk) 01:10, 15 September 2011 (UTC)


 * Yes, that should extend your total memory capacity. However, keep in mind that paging space is MUCH slower than RAM, so the need to continuously move data between RAM and the paging space will slow your computer to a crawl. StuRat (talk) 04:08, 15 September 2011 (UTC)

free service to monitor a page for changes and e-mail you
is there a free online tool that will monitor a page for changes (like every minute or five minutes) and e-mail you if there are any?

p.s. yeah I know I should become an elite unix hacker, then a simple script on one of my "boxen" would do it, with curl and sendmail and whatnot, but I don't have 10 years for this sorry. 82.234.207.120 (talk) 16:29, 14 September 2011 (UTC)


 * See Change detection and notification. ---— Gadget850 (Ed)  talk 16:47, 14 September 2011 (UTC)


 * Most of these services only check once a day or something similar (changedetection.com says they do it once a day). --Colapeninsula (talk) 09:04, 15 September 2011 (UTC)

Returning inverses of time intervals in SQL?
At work, we have a database table, let's call it, containing two columns,   and. These columns are of type  and represent time intervals. The intervals are guaranteed not to be truly overlapping (i.e. the start of one interval can exactly equal the stop of another, but there are guaranteed not to be any overlaps of non-zero length). I can easily find a set of time intervals from this table with a query such as this: SELECT TSTART, TSTOP FROM VALIDITY ORDER BY TSTART ASC, TSTOP ASC; But now I had to find all sub-intervals of a given period not belonging to any interval in the table. I haven't found any way to do it in SQL, so I did it by fetching all intervals within the period from the table, and then counting all intervals between them (i.e. from the stop of one interval to the start of the next one). Is there a way to do this in SQL? J I P &#124; Talk 18:01, 14 September 2011 (UTC)


 * In general, SQL is not very efficient at finding first, next, or last items. I work with hospital data. I regularly have requests for things like the last blood pressure from everyone seen in a certain time period. The only way to do it efficiently is to first make a table of patients (selecting the patient's ID) and the max visit date (selecting max date) limiting by the time period. Then, rejoin the table I made to the original table on patient ID and date to get the blood pressures per patient on that date. What you apparently want is a Next Start Date column for each record. I assume you don't want to add that. You need to make a new table that contains each record and the next start date for each record. Filling it will be a bit of a trick. You want, per record, the minimal start date such that the start date is >= to the records end date. Then, join that to the original table and you have intervals from stop to start (you can omit the ones where stop=start). -- k a i n a w &trade; 19:01, 14 September 2011 (UTC)


 * I'd think you'd want to create a VIEW using the sorted SQL statement you provided first:

CREATE VIEW VALIDITY_VIEW AS SELECT TSTART,TSTOP FROM VALIDITY ORDER BY TSTART ASC, TSTOP ASC;


 * Then use the ROW_NUMBER in the view for the follow-up SELECT, something like this:

SELECT A.TSTOP,B.TSTART FROM VALIDITY_VIEW A   AND VALIDITY_VIEW B  WHERE B.ROW_NUMBER = A.ROW_NUMBER+1 AND B.TSTART > A.TSTOP;


 * StuRat (talk) 21:03, 14 September 2011 (UTC)

InterGlobe Technologies Logo
according to my knowledge this is the InterGlobe Technologies logo — Preceding unsigned comment added by Kundan.hit (talk • contribs) 19:08, 14 September 2011 (UTC)


 * We have an InterGlobe Technologies article, which has a small copy of their logo there. The logo shown in that article matches the one they show on their website. -- Finlay McWalterჷTalk 19:13, 14 September 2011 (UTC)


 * (EC) We can't see a file on your computer, you will have to upload it to somewhere, probably not here until details on this likely copyrighted logo are sorted out. Anyway are you suggesting File:InterGlobe Technologies logo.jpg is not the correct logo for InterGlobe Technologies? Because the logo seems to be the same one as on their website albeit at a lower resolution (which is required by our copyright policies) Nil Einne (talk) 19:15, 14 September 2011 (UTC)

cross platform line breaks
I'm sharing text files (using dropbox) with people using macs. I'm using windows. The problem is that line breaks created on the macs don't show up at all in notepad on windows. Is there anything I can do on my end to correctly view these files with linebreaks? 209.147.145.88 (talk) 20:09, 14 September 2011 (UTC)


 * Use Wordpad instead of Notepad. It supports the Unix/Linux/Mac-style line endings without any hassle. -- k a i n a w &trade; 20:13, 14 September 2011 (UTC)


 * Notepad++ is a decent free Notepad replacement that supports Unix/Win/Mac line endings. It's a text editor, not a word processor like Wordpad. Pretty much any other Notepad replacement would work as well. -- BenRG (talk) 03:57, 15 September 2011 (UTC)

Which Linux rescue disc and which prompt?
I have a gateway NV78 with a 64 bit Intel Duo Core processor running Windows 7 which has crashed due to downloading a file which has apparently rewritten my registry. The system will start to boot prompting me to use normal or safe booting, but neither will reach a running windows screen. An acquaintance used a Linux OS rescue disc to boot the computer and to transfer a few files from the computer's hard drive to an external iomega drive I own, which worked great. But he wants to charge me $250 to save all my files.

I am not a total idiot, and successfully created a rescue disc from http://www.sysresccd.org/Main_Page which will run on my PC, but I can't seem to get to an interface from any of the prompts which will let me access the files on the crashed PC's hard drive so I can save them to my external iomega. (I know these files are accessible, my acquaintance moved 15G of them successfully to the Iomega and I have accessed them on my Mac, no problem.)

Should I have downloaded some other rescue disc than the www.sysresccd.org one? Does anyone have a url for the iso image file of a better Linux rescue disc? Or am I just missing the appropriate prompt on the disc I have? My thanks for any help. Do be aware I have searched the archives here, but find no obvious solution. Again, my thanks. μηδείς (talk) 22:00, 14 September 2011 (UTC)
 * At what point in the quick start guide are you having trouble? If you get yourself into the graphical environment there's a pretty good chance it'll let you just click on things to mount them and so on and so forth- should make life easier. Nevard (talk) 01:23, 15 September 2011 (UTC)


 * Thanks, I did, by brute force of trying every boot prompt, get to a graphic environment with that rescue disk. But once there I was totally lost--primarily because the icons were neither intuitive nor plainly labeled in idiomatic English.   But what I did find, using this article: http://en.wikipedia.org/wiki/List_of_live_CDs#Rescue_and_repair_live_CDs, was the link to the Bootmed Live CD (actually large enough in the 64 bit version to require a 770MB CD or a DVD) where I successfully downloaded the live Ubuntu rescue disc, which is just like a graphic windows interface.  Just a few minutes ago rescued my small movie collection from my disabled PC, and transferred the files to my external hard drive, and then to my Mac, where I celebrated by watching the Giedi Prime sequence from the extended version of the 1984 Dune.  The answer for a 64 bit Windows 7 user seems to be to go directly to the 64 Bit Bootmed download.  It works elegantly. Thanks to all for the help offered.μηδείς (talk) 04:01, 15 September 2011 (UTC)


 * A 32-bit boot CD can recover files from 64-bit Windows (and vice versa). I'm not sure why they even offer a 64-bit version of BootMed. Maybe there are newer PCs that don't support 32-bit operating systems at all. If you have a Windows 7 install CD, booting the Windows 7 CD and selecting "repair" might fix your Windows installation, avoiding the need to start from scratch. You can also use a Windows 7 install CD to rescue files from your hard drive, though you have to do it from a command prompt. -- BenRG (talk) 04:11, 15 September 2011 (UTC)

It says in the boot splash how to start X from sysresccd. I suggest you read more carefully in future. ¦ Reisio (talk) 15:01, 15 September 2011 (UTC)


 * I simply went with the 64 bit version since I knew the Gateway had a 64 bit processor. Had the Bootmed live CD not worked, I'd've tried the 32 bit version.  It did work.  As for Reisio's ever so helpful advice, I can read Estonian.  No problem.  It's written in the Latin alphabet,  Doesn't mean I know what it means.  Your advice is like telling an Englishman who wants to be understood by monolingual Frenchmen to speak louder. μηδείς (talk) 19:35, 15 September 2011 (UTC)

It's more like telling you to read more carefully in future: Graphical environment ¦ Reisio (talk) 01:28, 21 September 2011 (UTC)