Wikipedia:Reference desk/Archives/Computing/2009 October 27
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October 27
editComputer shutting off
editI have a brand new PC. Twice over the last two weeks, the power has shut off unexpectedly. I'm going to take it in because it's still under warranty, but I'd like get an idea of what may be happening so I don't sound like a complete doofus when I'm explaining the problem. I'll just be surfing the net or whatever and the main power shuts off: hard-drive stops spinning, fans stop, LED on the power button shuts off, etc. However, the little green LED where the ethernet plugs in is still on, as is one of the other little LEDs inside the tower. I'm barely an amateur when it comes to PC hardware, but my guess is that there's something wrong with the power supply and that some, but not all, of the power cords that feed the various devices are getting cut off. Turning off the switch at the back/unplugging and replugging the external power cord seem to fix the situation and 'puter is back up and running again in a few minutes. Sound familiar? Anything else I should note before placing the call? Matt Deres (talk) 00:00, 27 October 2009 (UTC)
- At a guess it's overheating as I'd expect it to turn off like you described, although if the computer is only 2 weeks old then it seems extremely unlikely that it's blocked with dust. The easiest way to verify this is to run it with the side of the case, although if it only happens once every two weeks then that's really quite hard to test. I'd at least make sure you report it as a problem even if you don't want to fix it right now so they at least have a record you told them of it. ZX81 talk 00:47, 27 October 2009 (UTC)
- Most likely you're underpowered, which means that the power supply is not supplying enough power to all your components. If your graphics card for example needs to draw more power, and the PSU cannot supply it, your computer will shut off as a precaution. Post your PC specs here if you need more help. Sandman30s (talk) 18:07, 27 October 2009 (UTC)
- In my experience, overheating causes spontaneous reboots rather than spontaneously turning the computer off. --Tango (talk) 19:57, 27 October 2009 (UTC)
- I've had over-heating issues on a previous machine and this just doesn't seem the same. Hell, the box is still cold to the touch. :) The case is clean, the fan is quiet, and we don't have the furnace on yet; I just don't think it's overheating. Both times the machine shut off I was literally just surfing the web and not even doing anything graphically intensive. I have a high end graphics card (ATI 4600-something) and a quad core CPU, but I would think it still ought to be okay with a 350W PS. Matt Deres (talk) 00:12, 28 October 2009 (UTC)
- Heck, no! Exactly what I said. It's not overheating. High-end graphics cards need at least 500W and I'm not even going to check for references; you can check those yourself. Whoever sold you a 350W PSU gave you a raw deal to cut costs. A higher PSU will anyhow put less strain on your components. Sandman30s (talk) 10:47, 28 October 2009 (UTC)
- I agree with the above, you're underpowered. ATI themselves say you should have a 400W PSU (minimum) for the 4600 although it's best to go a bit over that as you don't really want a PSU running at full load all the time (especially if it's a cheap one). Regarding the initial (wrong) assessment at overheating that I mentioned above, if the processor overheats then the computer will shut off, but if another component like GPU overheats then it's not as controlled and you get system instability/random reboots. ZX81 talk 13:27, 29 October 2009 (UTC)
- Heck, no! Exactly what I said. It's not overheating. High-end graphics cards need at least 500W and I'm not even going to check for references; you can check those yourself. Whoever sold you a 350W PSU gave you a raw deal to cut costs. A higher PSU will anyhow put less strain on your components. Sandman30s (talk) 10:47, 28 October 2009 (UTC)
- I've had over-heating issues on a previous machine and this just doesn't seem the same. Hell, the box is still cold to the touch. :) The case is clean, the fan is quiet, and we don't have the furnace on yet; I just don't think it's overheating. Both times the machine shut off I was literally just surfing the web and not even doing anything graphically intensive. I have a high end graphics card (ATI 4600-something) and a quad core CPU, but I would think it still ought to be okay with a 350W PS. Matt Deres (talk) 00:12, 28 October 2009 (UTC)
Memory timing on XFX 750i SLI
editHello there, I want to have appropriate memory timing on this mobo. I am using Transcend DDR2 4GB (2*2 GB) 800MHz (1.8V). In CPU-Z software, under "Memory"" and "SPD" I found the following information and memory timing:
Module size: 2048 MBytes
Max Bandwidth: PC2-6400 (400MHz)
Part number:JM800QLU-2G
Serial number:007FCOC
Timings table:
- DRAM Frequency: 400 MHz
- CAS#Latency:6.0
- RAS#toCAS#:6
- RAS#Precharge:6
- tRAS:18
- tRC:24
- Command Rate: 2T
As I am having numerous random freezing with this board (XFX 750i SLI). I read same problems in other boards where people solved them by changing ram timing on their board.
I want to give last try on it. In BIOS, DRAM Frequency everything is auto. Should I change memory timing there (based on above mentioned timing table)? Thanks in advance--119.30.36.37 (talk) 00:57, 27 October 2009 (UTC)
- That is already quite conservative (normal RAM run at 5-5-5-24, good RAM can run at 4-4-4-16 or even lower). You should run a memtest to see if the problem is actually in your memory. --antilivedT | C | G 11:44, 27 October 2009 (UTC)
- I have run numerous testing on ram (memtest86 and memtest 86+) including other rigorous testing. Have not found anything wrong with it. I suspect my board can't take the density of ram. Whatever the issue I want to know whether this configuration should do any good for performance.thanks--119.30.36.53 (talk) 04:54, 28 October 2009 (UTC)
programming languages
editHello, I'm a total noob who is just starting to learn html and css. What other programming languages are best for me to take a foothold on? Thank you. --198.163.150.5 (talk) 03:11, 27 October 2009 (UTC)
- html and css aren't really programming languages. I would recommend you learn C as most other languages can be easily picked up once you are good at C.
- I suggest you start with JavaScript. If you are learning HTML and CSS, you are likely interested in web design. Therefore, you need to know JavaScript. From there, I assume you will get into dynamic pages. What you learn is based on what your webserver supports. If it has PHP on the backend, you need to learn PHP. If it has ASP on the backend, you need to learn ASP. You might have a choice. On my webserver, I can use PHP, Ruby, Perl, or compile C/C++ modules. -- kainaw™ 04:11, 27 October 2009 (UTC)
- I agree with Kainaw. I've developed many web sites and JavaScript has helped me very much. So, after you're done learning HTML and CSS, learn JavaScript. It's really a blast to learn. Then, learn Photoshop. I can't emphasize that enough. You need to learn Photoshop if you want to make web sites. That's where web developers and designers spend most of their time, because the best sites have lots of pictures. Then learn PHP or ASP.NET (but not regular ASP, as it's not as good as ASP.NET). Some people use JavaScript with CSS for their visual effects (like fading in and out, rollovers, etc.), but I use Flash. It's faster than JavaScript and looks better. But, it's another thing you'd have to learn and you "have to" pay for the IDE to develop it.--Drknkn (talk) 07:27, 27 October 2009 (UTC)
- Instead of "Photoshop" you should say "graphic design", because that's where the real skill lies. But, I don't see how is this relevant to a budding programmer. Python and Ruby (and Ruby on Rails) are also good choices to dabble with. --antilivedT | C | G 11:50, 27 October 2009 (UTC)
- Well, HTML and CSS are not programming languages at all. --Andreas Rejbrand (talk) 13:43, 27 October 2009 (UTC)
- HTML is a language! Why else is it Hyper Text Markup LANGUAGE?Accdude92 (talk to me!) (sign) 13:46, 27 October 2009 (UTC)
- Sure, but the fact that it's a language does not make it a programming language. decltype (talk) 13:55, 27 October 2009 (UTC)
- It's just markup—it does formatting, nothing more, nothing less. You can't express, say, logical statements with it. --Mr.98 (talk) 14:36, 27 October 2009 (UTC)
- HTML is a language! Why else is it Hyper Text Markup LANGUAGE?Accdude92 (talk to me!) (sign) 13:46, 27 October 2009 (UTC)
- I usually say that the main difference is that a programming language tells the computer what to do. It better do it. A markup language (like HTML/CSS) asks the computer to do something. It might do it. It might not. It might do something radically different that you expect. In some areas, learning to effectively use a markup language can be far more difficult than learning to effectively use a programming language. -- kainaw™ 15:16, 27 October 2009 (UTC)
- Replying to "HTML is not a programming language" with "HTML is a language!" is like replying to "Angela Merkel is not French" with "Yes she is European!". Not all computer languages are programming languages. For example, Wikipedia markup is a kind of computer language. Would you call it a programming language? As for the distinction between markup and programming languages, I have to cite the only scientific paper I ever wrote (a university seminar paper): "Programming languages specify how to do things. Markup languages specify what things are like." This is the best definition I've seen so far, in my opinion. JIP | Talk 19:45, 27 October 2009 (UTC)
- Educational programming language is an article of interest, and I'd start with BASIC. See below where Accdude92 asked a similar question. Comet Tuttle (talk) 17:26, 27 October 2009 (UTC)
- I like Rebol because you can do a lot with just a few words, including accessing the internet. The Wikipedia article is too abstract, but see the Absolute Beginners tutorial links at the bottom. 84.13.180.244 (talk) 23:18, 27 October 2009 (UTC)
- I really think you need to start with something C-like. For our OP, there is no doubt whatever that PHP and JavaScript are the ones to attack first. BASIC is an evolutionary dead-end. There are no other significant languages that are like it - it's not particularly useful for some particular niche application - and it's a piece of junk for general-purpose use - it needs to "just die already". When you know JavaScript and/or PHP, you can go on to learn 'grown up' languages like Java and C++ - and then there is nothing you can't write. Once you've learned one programming lanugage, the second one is fairly easy - and the third through twentieth are very easy! I agree with the previous respondants though - HTML, CSS, XML and such like are definitely not programming languages - they are properly called "markup languages". SteveBaker (talk) 04:56, 28 October 2009 (UTC)
If you want to become skilled at programming, you must learn several programming languages. An approach that works for some people is to start with a language that has immediate benefit -- one that lets you extend projects that you are already working on. For someone who has worked on a Web site, this would usually be JavaScript or PHP; or possibly Visual Basic, Python, or Perl.
However, that approach does not work for everyone. Some people want to know as much as they can handle about what the computer is doing at a lower level -- they are interested in learning control over the computer, not in extending existing projects. For such a person I would recommend that they learn C. (No, not C++ or Java. Those are for people who want to get a job programming, which is not the same thing as learning.) A person who really wants to deeply understand how computers work should then learn assembly, possibly on a smaller-scale computing system such as an embedded system -- like a PIC or Atmel AVR microcontroller. (Which you can learn C on using the Arduino toolset.)
Finally, some people approach computing from mathematics, and want to learn not how computing can help me nor what is a computer, but rather what is computing. For such people I would recommend learning Scheme followed by Factor and Haskell.
As you can probably tell, I am not really sure which of these groups I belonged to. --FOo (talk) 05:41, 29 October 2009 (UTC)
C Malloc pointer
editi want to know how can i use malloc when i return a structure pointer in a function in c programming language —Preceding unsigned comment added by 61.2.48.30 (talk) 06:21, 27 October 2009 (UTC)
- Like this:
struct MyStructure* allocate_mystructure() { return (MyStructure*)malloc(sizeof(MyStructure)); }
I'm not sure if that cast should be there. From what I've heard,
struct MyStructure *pointer = (struct MyStructure*)malloc(sizeof(struct MyStructure));
is needless, and can actually hide errors. malloc()
returns a void pointer, which C always knows to automatically assign to any other pointer, but by casting it, you are second-guessing C, and if the cast doesn't work, the program will crash. The cast will usually work, but there are some arcane cases (for example, different kinds of pointers having different address lengths) where it won't, and by using the cast, you are telling C: "Shut up, I know what I'm doing better than you." However, I'm not at all sure how it works when automatically returning a pointer from a function. I might be right, or you might be right. Lastly, on a different note, in C, you have to always use the struct
keyword. Only in C++ can you omit it. JIP | Talk 20:18, 27 October 2009 (UTC)
- C will always automatically cast from a void pointer to a specifically-typed pointer, so the cast is not necessary. (Note that this is not the case for C++.) As JIP points out, casts are generally a bad thing and should be avoided. This C code compiles without warnings using MSVC version 6.
#include <stdlib.h> struct MyStructure { int i; int j; } ; struct MyStructure* allocate_mystructure(void) { return malloc(sizeof(struct MyStructure)); } void main(int argc, const char *argv[], const char *envp[]) { struct MyStructure *s; s = allocate_mystructure(); s->i = 1; s->j = 2; free(s); }
Mitch Ames (talk) 23:57, 27 October 2009 (UTC)
Actually, your declaration of main()
causes undefined behaviour. It might work all correctly for MSVC, but there's nothing to guarantee it would on any other compiler. Here's a better version:
#include <stdlib.h> struct MyStructure { int i; int j; } ; struct MyStructure* allocate_mystructure(void) { return malloc(sizeof(struct MyStructure)); } int main(int argc, char *argv[]) { struct MyStructure *s; s = allocate_mystructure(); s->i = 1; s->j = 2; free(s); return 0; }
JIP | Talk 05:48, 28 October 2009 (UTC)
- Noted. Thanks for the tip. Mitch Ames (talk) 23:29, 28 October 2009 (UTC)
ffshrine
editI need to go onto gh.ffshrine.org, but for the past few days, I have been unable to because of a donation message. How can I bypass that message? jc iindyysgvxc (my contributions) 07:41, 27 October 2009 (UTC)
- You could use Google's "cache" feature. Search for "site:gh.ffshrine.org" and click on "cached" instead of the usual search links. Not all website functionality will be available. Presumably you could also make a large donation as they request. It's unlikely that there will be a technical workaround that is ethical and legal. --Sean 19:17, 27 October 2009 (UTC)
Troubleshooting: scratches on CD/DVD media
editI have a disc for software which will not function properly. Obvious software issues have been ruled out, so I'm trying to nail down hardware issues. There are some light scratches on the disk, and I'm wondering if one of these happens to be stopping the computer from reading some critical piece of data. The computer recognizes the disk and I can copy the contents of the volume without errors.
Does this rule out damage to the disk as the cause of the software not running? SDY (talk) 08:51, 27 October 2009 (UTC)
- I would expect that if you can read all the files on the disk, then the software ought to be able to when running, also. However it is possible that the disk has some form of copy protection that complicates the issue. (Although with copy-protection I would expect the reverse, ie the software runs but you can't copy the files manually.) Mitch Ames (talk) 10:03, 27 October 2009 (UTC)
- There are known compatibility issues between Vista and this software (imagine that!) but I'm following some instructions on how to avoid them. Help desk time, I guess. SDY (talk) 10:10, 27 October 2009 (UTC)
Font identification...
editHi! Can anyone identify the font (I think it's just one font) in these posters/book covers for me? THE AWARD-WINNING MUSICAL / THE EUROPEAN UNION / POLITICAL PHILOSOPHY / IDEOLOGY
Thanks! ╟─TreasuryTag►presiding officer─╢ 10:55, 27 October 2009 (UTC)
- The
twothree OXFORD pubs look to be in Lithos; something like Lithos Regular -- Finlay McWalter • Talk 11:09, 27 October 2009 (UTC)
- And the bottom line of the Lion King is probably Lithos Black; the text "THE LION KING" isn't (notice how the shape of the N is so different) - it may have been manually produced by the graphic artist. -- Finlay McWalter • Talk 11:18, 27 October 2009 (UTC)
- Perfect—thank-you very much! ╟─TreasuryTag►assemblyman─╢ 13:57, 27 October 2009 (UTC)
- And the bottom line of the Lion King is probably Lithos Black; the text "THE LION KING" isn't (notice how the shape of the N is so different) - it may have been manually produced by the graphic artist. -- Finlay McWalter • Talk 11:18, 27 October 2009 (UTC)
- (Oh, how I hate Lithos.) The names of the authors on the Oxford covers are in Helvetica, for what it is worth. --Mr.98 (talk) 14:00, 27 October 2009 (UTC)
Line printer computer font?
editWhat typeface was used on the early line printers? Is there a computer font derived from the line printer era?
- Courier (typeface)? —Preceding unsigned comment added by .isika (talk • contribs) 13:39, 27 October 2009 (UTC)
- No, Courier and Courier New are available, but they started with the IBM Selectric typewriter, not the line printer of mainframe fame.
- There's a nice close-up shot here. Something sans-serif. Not unlike Andalé Mono (which is obviously based on the same aesthetic). --Mr.98 (talk) 14:30, 27 October 2009 (UTC)
- You can also try Consolas font that is included in Microsoft Office 2007, Vista and Windows 7. It's a monospaced font. --95.25.38.66 (talk) 18:29, 27 October 2009 (UTC)
- By early line printers, I presume you mean those with fixed fonts, such as drum, chain, finger and band printers. Those early typefaces were based on typewriter and teletype fonts. The classic font is Courier, which was designed for typewriters but predates the IBM Selectric typewriter and has been available on just about every line printer. American Typewriter is a similar typeface. You can find free fonts with a search for typewriter font. ---— Gadget850 (Ed) talk 21:09, 27 October 2009 (UTC)
The term "line printer" can also include a dot-matrix printer, although many dot-matrix printers were capable of printing graphics as well as lines of text. Dot-matrix printers' typefaces tended to be simple sans-serif bitmap typefaces; earlier and cheaper ones frequently lacked the ability to print descenders, so for instance the lowercase letter "p" was printed as a small-caps uppercase "P". Once the Japanese manufacturers got into the business and needed to print kanji, the resolution of dot-matrix printers got a heck of a lot better. --FOo (talk) 04:07, 29 October 2009 (UTC)
- Line Printer is a fairly specific term, and does not include dot-matrix printers. As for the claim about when and why resolution increased, I'd like to see a reference. --LarryMac | Talk 13:09, 29 October 2009 (UTC)
Programming/Scripting
editWhat language is best for beginners?Accdude92 (talk to me!) (sign) 13:42, 27 October 2009 (UTC)
- There's no "best"; there are probably a dozen or so languages that are perfectly adequate for beginners. Python and ruby and javascript are all perfectly fine for beginners, logo was invented for that job, and people who've learned visual basic, java, or c# have grown up to be perfectly effective programmers. Plenty of university students get, as a first language, haskell or common lisp; I know people who got prolog as a first language (that's where I'd probably draw the line). If I were to give one answer I'd say "python", but that's just an opinion (and you know what they say about opinions). -- Finlay McWalter • Talk 13:53, 27 October 2009 (UTC)
- How dedicated are you and what do you want to do with it? This can answer the question perhaps best. If you are doing it as a hobby and have a limited attention span, you might want to try something that allows you to make shiny, fun, useful programs fairly quickly. (PHP probably falls into this category, along with other web scripting languages.) It's not the same approach as doing it by-the-book, from-the-basics (as C might be). In the end, what you learn from programming is not the specifics of the language so much as the general approach. This can be applied multiple languages... but there is definitely a difficulty curve on languages, depending on what you want to do with them. --Mr.98 (talk) 14:54, 27 October 2009 (UTC)
- The Educational programming language article may be of interest to you. Personally I would start with some version of BASIC — that article makes Microsoft Small BASIC look interesting — but my advice to start with BASIC is just because that's what I started with. Comet Tuttle (talk) 17:25, 27 October 2009 (UTC)
- I like Rebol - see the Absolute Beginner tutorial at the end of the article. and the Kid's tutorial. Rebol can do a lot with just a few words, rather than pages and pages of code in other languages, including accessing the internet. 84.13.180.244 (talk) 00:01, 28 October 2009 (UTC)
- I think you may overestimate the amount of code needed to do "a lot":
import urllib
i=0
for l in urllib.urlopen("http://docs.python.org/library/urllib.html"): i+=1; print i,l[:-1]
use LWP::Simple;
print ++$i," $_\n" for split "\n",get 'http://search.cpan.org/~gaas/libwww-perl-5.800/lib/LWP.pm';
import java.io.*;
import java.net.*;
public class Curl {
public static void main(String[] args)
throws MalformedURLException,IOException {
BufferedReader br=new BufferedReader(new InputStreamReader(new URL("http://java.sun.com/j2se/1.4.2/docs/api/java/net/URL.html").openConnection().getInputStream()));
int i=0;
String line;
while((line=br.readLine())!=null) System.out.println(++i+" "+line);
}
}
- That's three implementations of "accessing the Internet" (and, to do something perhaps useful, adding line numbers to the retrieved webpage) in 16 lines, each in a mainstream language with millions of users, one of which is not known for its brevity. Please don't scare a beginner away from the big, well-developed programming communities into a cloister that (merely due to a lack of manpower) will not be nearly as good at helping them along. --Tardis (talk) 14:44, 28 October 2009 (UTC)
- Oh, just for fun:
- That's three implementations of "accessing the Internet" (and, to do something perhaps useful, adding line numbers to the retrieved webpage) in 16 lines, each in a mainstream language with millions of users, one of which is not known for its brevity. Please don't scare a beginner away from the big, well-developed programming communities into a cloister that (merely due to a lack of manpower) will not be nearly as good at helping them along. --Tardis (talk) 14:44, 28 October 2009 (UTC)
(echo $'GET /LDP/abs/html/devref1.html HTTP/1.1\nHost: tldp.org\nConnection: close\n\n' >&0; tr -d '\r' | sed '1,/^$/d' | cat -n) <>/dev/tcp/tldp.org/www
- Compare that with the one-line Rebol programs linked to from the article. 92.29.91.83 (talk) 19:59, 28 October 2009 (UTC)
w3schools
editDoes anyone else use that website to learn scripting?Accdude92 (talk to me!) (sign) 14:03, 27 October 2009 (UTC)
- I imagine many people do. Personally, I have often found W3C sites to be very useful references. If you have a problem or question about what you're learning from that site, you can post it here (consider reading How to ask good questions or something similar; the location of the Wikipedia version of this guide has momentarily deserted me). If you're looking for others to learn alongside, you may want to enquire at your local college - their IT department probably runs evening classes - or conscript some of your friends to learn with you. --Kateshortforbob talk 15:18, 27 October 2009 (UTC)
- I'm not actually sure that site is affiliated with the W3C. It doesn't mention them on their website, but I might be wrong. Thanks, gENIUS101 21:22, 27 October 2009 (UTC)
- Oops, yes - good point! I think I misread that. --Kateshortforbob talk 10:05, 28 October 2009 (UTC)
- I'm not actually sure that site is affiliated with the W3C. It doesn't mention them on their website, but I might be wrong. Thanks, gENIUS101 21:22, 27 October 2009 (UTC)
Processor Architecture Copyright
editIs processor architecture covered copyright? If not then what is copyright dispute about in this litigation between Intel and AMD? I'm not asking for legal advice. --Melab±1 ☎ 15:50, 27 October 2009 (UTC)
- I took the liberty of fixing your link. --Sean 16:32, 27 October 2009 (UTC)
- I don't know of any case where the a court has upheld a claim that an architecture itself is subject to copyright. The specific copyright litigation between AMD and Intel concerned the copyright of microcode (which is, in essence, software); that is, Intel claimed that an AMD chip copied the implementation of an architecture, not just the specification. Of course other parts of intellectual property law do apply, including trademarks and patents. NEC's x86 compatible NEC V20 came with manuals that used different opcode mnemonics for all the instructions, although really the underlying opcodes were all the same as in an Intel chip - NEC didn't want Intel to be able to sue them for copyright infringement of Intel's processor manual (I think they also shipped an assembler that understood the NEC opcodes, although you could just use a regular assembler or compiler targeted at Intel and the resulting code ran fine on V20). -- Finlay McWalter • Talk 16:36, 27 October 2009 (UTC)
- There is no obvious reason why the specifics of chip architecture (e.g., the chip design) couldn't be copyrighted, and the general principles patented. There is nothing special about chip architecture, legally speaking. --Mr.98 (talk) 19:41, 27 October 2009 (UTC)
- In addition, in the USA mask designs (i.e. the physical layout of the components on a chip) are covered by restrictions similar to copyright, but not actually copyright law: see Mask work. --Lesleyhood (talk) 12:24, 28 October 2009 (UTC)
Using a webcam in Windows Vista
edithow to use built in webcam in windows vista home basic —Preceding unsigned comment added by 94.196.97.230 (talk) 18:33, 27 October 2009 (UTC)
- It would help if you indicated what computer make and model you are asking about. There is bound to be pre-installed software if there's a built-in camera, but without the specifics on the PC, it's hard to help. --LarryMac | Talk 18:52, 27 October 2009 (UTC)
- You need a program to make use of the webcam. It won't magically cause Windows to open a television screen and show you everything that it sees. A very common webcam program is Skype. -- kainaw™ 19:28, 27 October 2009 (UTC)
Use of laptop computers by the pilots of Northwest Airlines Flight 188
editI do not know a lot about laptop computers or the technology involved with them. That is why I am posting my question here on this Reference Desk. There was a recent incident involving Northwest Airlines Flight 188. The pilots missed (overshot) their destination by 150 miles, and they were out of contact/communication with authorities for over an hour. The pilots' version of events is that they were so engrossed with working on their laptops that they became oblivious to the passage of time and to the distracting noises of those attempting to communicate with them. Many people feel that the pilots simply fell asleep at the wheel (cockpit). So, my question is this. Isn't it easy for the investigating authorities to prove or disprove the pilots' version of events? Can't the authorities simply check out their laptops and look "within" ... at the hard drive or whatever? Will this data tell the investigators whether or not the pilots' version of events is true or false? Or will the laptops themselves yield no useful information? As I said, I do not know anything about laptops or the technology involved. But, I would think that the laptops can prove (or disprove) that the pilots were engaged in laptop activity, that internet sites were accessed and navigated, the dates and times of the laptop activity, etc. Isn't there some type of "bread crumb trail" on their laptops that will easily prove one way or another that the pilots are telling the truth ... or that they are lying? Or are there some other factors that I am missing here? Thank you. (64.252.124.238 (talk) 20:01, 27 October 2009 (UTC))
- It's not likely that any internet usage occurred, I don't think NWA has added WiFi to their fleet yet. Assuming the laptops were running Windows, then there would be system logs that would indicate various types of activity. --LarryMac | Talk 20:36, 27 October 2009 (UTC)
- Yes, you are quite right that this would be easy information to verify. More to the point, the pilots claim they were using a new company scheduling system, which will presumably itself keep records of accesses and will be easily accessible by the company, which the laptop might not be without a subpoena. --Sean 20:37, 27 October 2009 (UTC)
- Little data has been publicly disclosed about the investigation, but the pilots' laptops were their personal property and I think it's unlikely they were seized by the airline or by the FAA upon landing. They may have been asked for the laptops afterwards but there's not a great chain of custody here, if my guess is right. Comet Tuttle (talk) 22:09, 27 October 2009 (UTC)
- Even if there is not a great chain of custody ... no one can go "back in time" and change the history of what the data should accurately reveal ... or can they? Thanks. (64.252.124.238 (talk) 00:12, 28 October 2009 (UTC))
- They can, but it's trivial for a computer forensics expert to see through unless they are really skilled, and these are pilots not hackers. There are two easy ways to verify their claims:
- 1) check the file edit logs on the laptops
- 2) check the audio recording logs in the black box
- If they were indeed deeply immersed in discussing scheduling, there'll be a nice long recording proving it. My $50 says they both fell asleep. There were numerous cockpit alarms that would have easily interrupted any conversation... 218.25.32.210 (talk) 00:51, 28 October 2009 (UTC)
- They can, but it's trivial for a computer forensics expert to see through unless they are really skilled, and these are pilots not hackers. There are two easy ways to verify their claims:
- I also agree with you that they likely fell asleep. But -- being long-time pilots who are familiar with the two items you mention (laptop logs and audio logs) -- how can they think that they would "get away with it" (if indeed, they were sleeping and are lying about the laptops)? It doesn't make much sense. They must know that the laptop logs will be inspected, the audio logs will be inspected, etc. If they were asleep (which I think they were) ... aren't they smart enough to know that the "laptop excuse" and the "we were engrossed in discussion excuse" would get easily disproved? Thanks. (64.252.124.238 (talk) 01:01, 28 October 2009 (UTC))
- I assume these pilots would never do such a thing, but laptop hard disks can be fairly thoroughly erased with common utilities like Shred (Unix). In such a high profile case as this, of course, one could expect the airlines or the FAA to call in the FBI if such a thing were attempted, and the FBI allegedly possesses the most advanced sort of equipment (or processes) that can be used to undelete such deleted material ... so one could speculate that such attempts would end up futile. Anyway, 218, the cockpit voice recorder only records about 30 minutes, so there is no audio record of the "distracted" time period. Comet Tuttle (talk) 03:01, 28 October 2009 (UTC)
- It may be a moot point as this ref [1] suggests the NTSB hasn't taken the laptops and doesn't believe they would be of use and the pilots have already had their licenses revoked. Nil Einne (talk) 03:18, 28 October 2009 (UTC)
- Our article says "but contact with the aircraft remained lost until 8:14 p.m. CDT. The aircraft finally landed, over an hour late, at 9:04 p.m. CDT." "The flight data recorders were removed from the aircraft, but there was only 30 minutes worth of information. Over an hour's worth of information would have been needed for all of the information of the portion of the flight past Minneapolis to be available". It's not that clear but appears to me that none of the time they were out of contact and therefore maybe asleep is covered in the data recorders. Edit: See this was already discussed above, sorry missed it. Nil Einne (talk) 03:11, 28 October 2009 (UTC)
Thanks for the input. Much appreciated. (64.252.124.238 (talk) 15:09, 29 October 2009 (UTC))
MS Access 2000
editI am having a problem getting a master query to run based on a form. I want the query to filter based on the information on the form, however, if parts of the form are blank, I want it to display all.
Right now, I have:
Column1
Criteria: IIF(IsNull([Forms].[Master Form].[Field1]),””,[Forms].[Master Form].[Field1])
Column2
Criteria: IIF(IsNull([Forms].[Master Form].[Field2]),””,[Forms].[Master Form].[Field2])
Column3
Criteria: IIF(IsNull([Forms].[Master Form].[Field3]),””,[Forms].[Master Form].[Field3])
When I try to get it to run the query, it demands a parameter for Field1.
I did get it to work, with a form that focuses only on one field with the following
Column1
Criteria: [Forms].[1 Form].[Field1]
Or: [Forms].[1 Form].[Field1] Is Null
Please Help
Thank You
omnipotence407 (talk) 21:26, 27 October 2009 (UTC)
- A few thoughts from an old Access hand:
- 1. In that in your pasting of the criteria, the parentheses don't balance. I doubt that is the problem with the Query, but I'm just putting it out there.
- 2. Referencing data on forms can be tricky depending on the field. Is [Field1] something that is indicated by a TextBox? If so, the data kept in [Field1] might not be updating until after the TextBox loses focus. (The table data does not update until the control loses focus, generally.) So what you might try doing is accessing the specific name of the TextBox, e.g., give the TextBox for [Field1] the Name of text_Field1, and then access [Forms].[1 Form].[text_Field1], which ought to access the TextBox value.
- 3. One cheat-y way around this is to make it so that tables default to blank rather than Null, or that the form fields themselves default to blank instead of Null. It may not solve the underlying problem, though.
- That's about all I can make out given the information above. It sounds like a fairly typical Access snafu though—a pretty innocuous attempt to do something fairly obvious, stymied by very unhelpful error messages that often do not address the ultimate problem. --Mr.98 (talk) 22:09, 27 October 2009 (UTC)
- Yeah, I just miscopied that. I corrected that above. In this case, Field 1 is a combo box. The query activates after a command button is clicked running the SetValue Macro.
- I do not understand how using blanks would help, could you expand on that? The fields in the table are required to be filled in.
- I will be converting the database to 2007 soon. Will that help with this?
- Thanks, omnipotence407 (talk) 23:08, 27 October 2009 (UTC)
- Re: converting to 2007: probably not. This is not the sort of thing the Access people think is a "bug".
- I really do think the problem has to do with referencing the field vs. the control. I am betting the control has not updated the data field. Try this: rename the combo box to Field1_Combo, and change your query accordingly. See if that changes anything. As for blanks, all I mean is, "Null" is not the same thing as an empty string (what I am calling a blank, but is really ""). You can, if I recall, make it so that instead of fields defaulting to Null, they will default to an empty string. That may or may not be appropriate depending on the data in question. It's a hack and not a very good one, though. --Mr.98 (talk) 01:39, 28 October 2009 (UTC)
How to search eBay for everything within 20 miles?
editIs there any way to search eBay for everything within 20 miles no matter what it is? I would like to find what bargains are available locally without specifying a search term. Is there any way to do this please? The cheapest things often require personal collection, hence I want to find what's near. 84.13.180.244 (talk) 23:55, 27 October 2009 (UTC)
- I don't think there is such a feature on eBay - but a FAR better site for that kind of thing is CraigsList - it's organised primarily by distance and nearly everything there is for local pickup. You still need to narrow down the things you're interested in though - you'd be quite amazed the number of people within 20 miles who have stuff to get rid of. SteveBaker (talk) 04:33, 28 October 2009 (UTC)
Your description of what you need to do to search Craiglist seems no different from searching aBay. 78.147.183.120 (talk) 12:48, 28 October 2009 (UTC)
- Is Craiglist actually widely used outside the US? I see from [2] it does cover parts of the UK were the OP apparently comes from. That doesn't mean it's used much of course. For example I just found out it actually covers parts of NZ. However I wasn't aware of that and I suspect it's the same for many Kiwis. For example for Auckland I find only 4 items in the mobile phone section 2 items in the electronics section. There are quite a few men seeking women compared to those other examples but it's still pitiful and several of them are from outside NZ. TradeMe dominates the NZ auction market and because of our small size, population demographics heavily centred around urban areas, Auckland in particular and its design, it's quite easy to find items for pickup and many people do use it in that way. There are also other classified and auction sites which I would likely use before craigslist for NZ. A look in Malaysia [3] suggest it suffers from similar issues and although the Malaysian internet auction/classified scene is not as widespread as here in NZ there are definitely sites that I would try first. I looked at London and did find quite a bit of stuff but there may still be other better sites to try first Nil Einne (talk) 02:52, 29 October 2009 (UTC)