Wikipedia:Reference desk/Archives/Computing/2008 October 31

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October 31

Headphones

Why is only one side working? It doesn't look damaged, nor has it endured any, except for the fact that part of the wires are visible, and when I jiggle them a little bit, both sides stop working or one side regains sound but the other won't. They're not cheap headphones, so what's up with that? --Crackthewhip775 (talk) 04:18, 31 October 2008 (UTC)

The jiggle test is pretty indicative of a loose or crossed wire. If their nice enough and still udner warranty, try to have em repaired. Otherwise I'd suggest finding a screwdriver and sautering iron and doing it yourself (at your own risk). Or just get a new pair. For now I'd suggest you stop jiggling them, as that may be aggravating the problem (e..g. twisting loose wires) --Shaggorama (talk) 05:12, 31 October 2008 (UTC)

Thanks. --Crackthewhip775 (talk) 05:44, 31 October 2008 (UTC)

fstab permissions

Resolved

 – Thanks, changed the permissions by chmod. - Unpopular Opinion (talk) 08:43, 4 November 2008 (UTC)

I am trying to mount an ext3 partition in my home folder, this is the line I added to fstab

/dev/sda5       /home/user/mountpoint    ext3    defaults                0       0

I can see the mounted folders in /home/user/mountpoint but I'm not able to access the files; when I click on it, it says I do not have read/write permission to these files. What should I change in the fstab options? Thanks - Unpopular Opinion (talk) 06:38, 31 October 2008 (UTC)

It's probably just a file permissions issue. Doing a sudo chown user -R /home/user/mountpoint should fix it. --Sean 12:50, 31 October 2008 (UTC)

Or if you don't care about file permissions change defaults to defaults,umask=0000 --wj32 ^t/c 04:37, 1 November 2008 (UTC)

Actually nevermind, that only works for vfat and hfs. --wj32 ^t/c 10:36, 1 November 2008 (UTC)

USB

Help! My USB ports have stopped working. I need to urgently print and scan a document. My motherboard is ASUS A8N-VM. I can power up an iPod, but the PC fails to detect any hardware on both Windows Vista and Linux (Ubuntu). I need to resolve this urgently. =Nichalp «Talk»= 10:40, 31 October 2008 (UTC)

• Do you already have the document on the USB disc or is it on your harddrive? If it is on the USB, go to a copyshop. If it is still on your computer, try emailing it to someone and print it there. -- Mgm|^(talk) 13:09, 31 October 2008 (UTC)

I managed to resolve it by doing the latter, printing it out somewhere else, but no luck on the USB ports. I checked my BIOS settings and USB 1, 2 and legacy is enabled. =Nichalp «Talk»= 13:49, 31 October 2008 (UTC)

Have you tried reinstalling the USB driver? DaRkAgE7_[Talk] 18:47, 31 October 2008 (UTC)

I'm assuming it has to do with hardware, because the problem is OS independent. I read somewhere that you need to drain your system clock... but that's drastic I guess. =Nichalp «Talk»= 18:59, 31 October 2008 (UTC)

It sounds like a hardware failure rather than a configuration problem: according to the manual, there are no jumpers or BIOS settings that can disable USB. You could try clearing the CMOS RAM (unplug the computer, remove the CMOS battery, move the CLRTC jumper from pins 1-2 to pins 2-3, wait 15 seconds, move the jumper back, replace the battery, plug the computer back in), but I don't expect it to help. Since all the USB ports have failed, it's probably the controller chip rather than the ports themselves. If you've got a PCI bracket with USB ports or a case with front-panel ports, try hooking those up -- sometimes they're on a separate controller from the on-board ports. --Carnildo (talk) 22:23, 31 October 2008 (UTC)

Open office writer problems!

Resolved

Hi every time I draw a table on open office writer - save it, close open office and try to come back to my work the table has gone and my data is all mixed up on the page. Is there any way I can prevent this as I have had to re-draw my table several times now and if I exit open office I will have to do it again. Thanks. —Preceding unsigned comment added by 139.222.241.164 (talk) 11:07, 31 October 2008 (UTC)

What are you saving the file as? If you're saving as something like .rtf or .txt instead of .doc or the native Open Office Writer document type, it may just be that the file type you're saving as doesn't support the formatting you're doing. Laenir (talk) 13:40, 31 October 2008 (UTC)

I'm saving the file as a microsoft word 97/2000/XP file. Although my computer doesn't have microsoft office I generally save my open office documents as word documents so I can print them on another computer which only has MS office. Could the fact that I don't have microsoft office on my computer be anything to do with it? Thanks again. —Preceding unsigned comment added by 139.222.241.50 (talk) 17:26, 31 October 2008 (UTC)

That should not be a problem at all. However, I propose a stop-gap measure for you. Save all your documents in the native ODF. If you are not editing the document from another computer, export a final copy of your document as PDF. Just in case, also take a .doc exported copy with you. Kushal (talk) 12:19, 3 November 2008 (UTC)

Saving the document as a native open office file has resolved the problem - Thanks a lot! :)

Glad to be of any help! Kushal (talk) 03:37, 5 November 2008 (UTC)

crappy keyboard probs

I bought a cheap keyboard - the caps lock is right next to the A key and the Insert key is right next to the Delete key - I keep accidentally hitting them. Is there a simple way of disabling them? Adambrowne666 (talk) 12:14, 31 October 2008 (UTC)

A quick Google search brought up this link. It involves playing with the registry, so don't do it if you don't know what you're doing or not in a position to fix it. However, getting using new keyboard always takes time (for instance, the keyboard on my desktop has an unusual layout of the home/ins/end/pageup keys, whereas my notebook has them all over the place, some requiring the use of function keys. It took me a while to get used to both, so stick with it! Booglamay (talk) - 12:21, 31 October 2008 (UTC)

KeyTweak is a utility program that can be used to remap and/or disable keys for computers running Microsoft Windows. [1] --Aude (talk) 13:38, 31 October 2008 (UTC)

Where are those keys supposed to be? I rarely see keyboards that do otherwise (mostly those that put Caps Lock at the very lower-left). --Tardis (talk) 16:05, 31 October 2008 (UTC)

The OP may mean that the top face of the CapsLock is right beside the A key, where my CapsLock key is actually uniquely shaped, with the portion beside the A key stepped down so that (functionally) there's a gap between the two, even though they're side by side. Mine is just a cheap Acer, but I've seen the setup before; no idea how common it is. Matt Deres (talk) 19:04, 31 October 2008 (UTC)

For CapsLock (which I hate with a passion) I have used several solutions:

1. Simple: Remove the keycap - flush it down the nearest toilet.
2. Superglue: Remove the keycap - squirt superglue into the hole it leaves behind. Gently replace the keycap (do NOT depress it or it'll stick in the DOWN position!).
3. Reversible: Lever off the keycap. Generally - there is a cylindical plastic projection beneath with the actual switch at the bottom. You can roll up a piece of paper or thin card such that it wraps around the outside of the cylinder but is a little taller - taping this in place prevents the key from going down - but is easily reversible just by sliding your paper tube off of the plastic cylinder.
4. Reprogramming. With some operating systems, there is a 'preferences' option to disable the capslock key.

SteveBaker (talk) 03:56, 1 November 2008 (UTC)

yep; just pop the capslock key off. for those who don't know, the keytops are just snapped into the switch mechanisms and can be popped off and back on. even when they're off, the stem of the switch sticks up so you can hit the key if you want to.

for another option, the accessibility section of control panel hides an option that makes the lock keys (scroll, num, caps) beep one way when they toggle on and another when they toggle off. should be on for the default, as far as i'm concerned. Gzuckier (talk) 05:48, 1 November 2008 (UTC)

Great! - I excised the offending keys like carious teeth! - thanks all 121.91.71.120 (talk) 00:41, 2 November 2008 (UTC)

Help! Can't log onto Internet on my laptop.

This is what happens:
1. I click on the Internet icon. It waits a while then it says "Work Offline: No connection to the Internet is currently available. To view Internet content that has been saved on your computer, click Work Offline. Click Try again to attempt to connect."
2. I click on "Try Again" then it says " Internet Explorer cannot display webpage".
3. I open the Wireless Network Connection. I double click on my landlord's wireless network which says "(landlord's name) - unsecured wireless network" and it shows full strength signal. Then I click on "Connect".
4. Then its says "Connected" but when I try to open Internet Explorer again, the same thing happens again at step #1.

I don't understand. I used to be able to log onto the internet fine with my landlord's wireless network (which by the way he allows me to do). But recently I can't at my apartment. However if I bring my laptop to work, it connects fine. Please help! --Emyn ned (talk) 13:31, 31 October 2008 (UTC)

Have you tried connecting to other websites, or using a program other than IE to access the internet? If you have access to the modem and router, have you checked they're plugged in and restarted them? Algebraist 13:48, 31 October 2008 (UTC)

Excuse me for my ignorance, but how do you connect to other websites or use a program other than IE? How do you know if you have access to their modem and router? --Emyn ned (talk) 13:59, 31 October 2008 (UTC)

[I indented your reply to Algebraist's comment for you.] There are many web browsers, like Internet Explorer, Firefox, and Opera. By "access" Algebraist means physical access — can you check that they're working and possibly power cycle them? --Tardis (talk) 16:09, 31 October 2008 (UTC)

When Internet Explorer displays the "Cannot display webpage" message, try clicking on the "Diagnose Connection Problems" button and follow all the steps. It might repair the problem. --Crackthewhip775 (talk) 20:17, 31 October 2008 (UTC)

Finding Errors in Excel

I am trying to find specific errors on an excel spreadsheet. I have columns that do Vlookups, and they generate a lot of #N/A (Value Not Avaliable error) errors. These are actually not a problem. Somtimes #REF! errors will happen, and these errors cause major problems. The sheet is large (1200 rows X 20 colums), so it can be kind of hard to find errors just by looking.

I can use the built in error checker, but it finds all of the #N/A errors along with the #ref! errors. I can write a macro to check IsError(ActiveCell.Value) but it also finds all formula errors.

So does anyone know how I can find ONLY the #REF! errors, while ignoring the #N/A errors? In other words how can I see the actual error code, so I can write a macro that only finds #REF!

thanks --Czmtzc (talk) 14:12, 31 October 2008 (UTC)

Can't you filter the columns to only look for "#N/A"? Laenir (talk) 14:31, 31 October 2008 (UTC)

Laenir's answer is the solution if the errors are confined to 1 (or a few) columns. #REF! are a referencing problem which I would assume are specific to your code/formulas, so I would consider checking your formulas in general, as they shouldn't #REF! unless you've made a mistake in the referencing. Alternatively you could write a macro that searches for #REF across each row and then if it finds one adds a value to a column which you can then filter (should be a simple macro - record yourself searching for #REF and use that to build a loop that goes through the rows and write code to add a value)/ 194.221.133.226 (talk) 15:53, 31 October 2008 (UTC)

Here's an interesting observation. A VLOOKUP formula with a column index number that is greater than the number of columns in the lookup table will return #REF! if Range Lookup is TRUE or if it finds the lookup value in the first column of the lookup table. But the same formula will return #N/A if Range Lookup is FALSE and it does not find the lookup value in the first column of the lookup table - even though it has been given an invalid column index number. So possibly your #REF! and your #N/A errors are due to malformed VLOOKUPs, and are equally serious. Gandalf61 (talk) 16:16, 31 October 2008 (UTC)

Sorry, the #N/A errors are from lookups taht aren't found. THe #ref! errors are when the lovely users delete a cell. --Czmtzc (talk) 21:39, 3 November 2008 (UTC)

If a cell you have found has an error e.g. IsError(cell)=True then the value of that cell tells you what error it is. A value of Error 2023 is a #REF! error.

Pass the value of the cell to this function and it returns the error. E.g.

If IsError(Range("A1").Value) = True Then Debug.Print ErrorName(Range("A1").Value)

Private Function ErrorName(errVal As Variant) As String
   Select Case CStr(errVal)
   Case "Error 2023"
       ErrorName = "#REF!"
   Case "Error 2042"
       ErrorName = "#N/A!"
   Case "Error 2007"
       ErrorName = "#DIV/0!"
   Case "Error 2015"
       ErrorName = "#VALUE!"
   Case "Error 2029"
       ErrorName = "#NAME?"
   Case "Error 2036"
       ErrorName = "#NUM!"
   Case "Error 2000"
       ErrorName = "#NULL!"
   End Select
End Function

Therefore, in your macro you can look to find just ref errors when you cycle through all the cells you want to check. I had the same problem as you so I wrote an excel add-in with a form, to highlight all the errors in an open book, with the option for ignoring certain errors, like #N/A!. -Phydaux (talk) 15:38, 3 November 2008 (UTC)

EXCELent!. That was exactly what I was looking for. Thanks Phydaux I really appreciate it. --Czmtzc (talk) 21:37, 3 November 2008 (UTC)

iPlayer

The iPlayer download for computers runs out after 30 days, is this the same for the download for portable devices? Thanks. 92.5.109.187 (talk) 14:41, 31 October 2008 (UTC)

No - They're available to download for 7 days, then expire after 7 days (annoyingly). The relevant help page is here — Matt Eason ^{(Talk • Contribs)} 17:57, 31 October 2008 (UTC)

Reaching localhost when I am offline

I have installed a program (Sage (computer algebra system)) that runs over my browser (Firefox) using the address http://localhost:8000. Unhappily, it only works when I am online.

What is wrong? Shouldn't localhost be always available? Mr.K. (talk) 17:41, 31 October 2008 (UTC)

Try 127.0.0.1. Also check if a proxy is enabled in Options -> Advanced -> Network. If it is, try entering localhost, 127.0.0.1 into "No proxy for" box. --grawity 19:45, 2 November 2008 (UTC)

Phantom Drive Labels in Vista

So when I open up my computer, I see all of my drives, but it doesn't show any of their names unless I hover the mouse over a drive. Unless my memory is going, they did show up until recently. I'm viewing large icons sorted by type. I feel stupid asking, but for the life of me I can't figure out how to make them show up. Also, none of the icon views (as opposed to list and details) show the labels. Argh! Thanks in advance. DaRkAgE7_[Talk] 18:37, 31 October 2008 (UTC)

Does this link help? Laenir (talk) 18:53, 31 October 2008 (UTC)

While it seems that person has the exact same problem as me, the solution there doesn't solve my problem. I tried it, and "show drive letters" was already checked. Any other ideas? DaRkAgE7_[Talk] 18:59, 31 October 2008 (UTC)

suppressing a page with nothing on it

In word I can't seem to get rid of a blank second page (the first page is jammed with stuff but if I try to delete whatever might be on the second page (which looks completely blank) I end up also deleting the last thing on the first page. Is there a way to just suppress the second page (to end up with a one-page resume?) Thanks! —Preceding unsigned comment added by 82.124.209.97 (talk) 19:17, 31 October 2008 (UTC)

Try placing the cursor immediately after the last character on the first page and hitting the "Delete" button (possibly a few times). If that doesn't work, then you could try to reduce the font size or remove any extraneous blank lines.--Zerozal (talk) 19:25, 31 October 2008 (UTC)

the reason that doesn't work is because the last character is inside a table. there's nothing outside the table, and try as I might the only way to delete the next page is to delete the last table as well, which I don't want to do . It really looks fine the way it is, I think I'll just keep it if no one has a suggestion (your second one would move up the last table so it's not flush with the bottom of the first page, which I don't want to do either...)

Sometimes Word will simply not let you suppress an additional page if for some reason it decides that the first page goes over the limit (even when it does not actually go over the limit). I have had the same problem at times. The bottom line is that, as Louis Menand said, "Microsoft Word is a terrible program." I know of no fixes other than trying to reduce the content on the first page. --98.217.8.46 (talk) 19:48, 31 October 2008 (UTC)

Thank you! I'll just live with it. I've sent the resume...

Just like that? In word? I hope you are not applying to Adobe Systems right now. (just kidding, don't even worry about it) What I have found useful is to go to the second page and press back space after getting rid of all table elements in the second page by cutting them (not deleting them). Please try that. Kushal (talk) 11:10, 1 November 2008 (UTC)

Reducing the bottom margin would not change the appearance of your page, and would make the second page go away. --NorwegianBlue ^talk 11:45, 1 November 2008 (UTC)

Alternative document formats like PDF could help, if you are sending in resumes. Consider "printing" only the first page into a PDF file using software such as PDFCreator. Kushal (talk) 22:31, 1 November 2008 (UTC)

Is it possible with XUL?

I'm new to XUL. But before I dive head first into it, I want to know if it is possible for me to read the browsers history files using XUL extensions. Also, can I write to a particular file on the disk using a XUL-based firefox extension?--Seraphiel (talk) 20:04, 31 October 2008 (UTC)

Random counting/picking

I want to write some code (in Python script) that can randomly "count" from x to y, picking each number in the range only once until all the numbers in the range have been chosen. Is there a name for an efficient algorithm or function that can already do this? I'd really like to give it a seed argument too, so I could replay the order it picked the numbers again. Antsoup (talk) 20:21, 31 October 2008 (UTC)

See Knuth shuffle for the algorithm, and random.shuffle(range(x,y)) for the library function. Unless $y-x$ is large, this should be fine. --Tardis (talk) 20:54, 31 October 2008 (UTC)

Because the shuffle algorithm uses a random function, you can specifically use a seeded random. Then, when you call the shuffle function, the random numbers used in the shuffle will the same random numbers used each time the randomizer is seeded with the same value before use. The advantage of using shuffle is that your function can take two parameters, count and seed (optional), and return an array of randomly ordered integers from 1 to count. Then, you can pull one of the integers off one at a time or undo a count (back up one) if you like. -- kainaw™ 20:59, 31 October 2008 (UTC)

This is great, exactly what I was looking for! Didn't even think of shuffle. Thanks a lot! —Preceding unsigned comment added by Antsoup (talk • contribs) 21:12, 31 October 2008 (UTC)

Shows what I know. Coming from a theoretical computer science background, I would have said:

“

tocount = range(1,10) #change to suit yourself
>>> while len(tocount):
	next = tocount[0]
	tocount.remove(next)
	print next
	#tocount.shuffle() #how?

”

:-P

—Preceding unsigned comment added by 82.124.209.97 (talk) 21:57, 31 October 2008 (UTC)

If I had to write it:

   source = range(N)
   sink = []
   while source:
       sink.append(source.pop(randrange(0,len(source))))

—Tamfang (talk) 07:45, 1 November 2008 (UTC)

You're a perl programmer and you know it!  :) —Preceding unsigned comment added by 82.124.209.97 (talk) 11:36, 1 November 2008 (UTC)

Is that good and/or bad? I've written only a few lines of Perl long ago. —Tamfang (talk) 01:47, 2 November 2008 (UTC)

Google question

How do you change the default page from .ca to .com? Even though I retype the address in the Internet options in Conrol Panel, it still stays the same. It's even harder to change in other browsers, such as Firefox. --Crackthewhip775 (talk) 20:43, 31 October 2008 (UTC)

What default page? Google's homepage when you go to www.google.com? They geotarget their audience and, if they think you are in Canada, they send you to www.google.ca. I have heard many people say that if you install the Google Toolbar you can set your default locale (to US) and get www.google.com as the default. -- kainaw™ 21:03, 31 October 2008 (UTC)

Yes, I believe you can change it using the Google toolbar. If you dont use it, then here is a link to go to google.com overriding the geotarget script. You can see this link on google.ca too.--thunderboltz^(TALK) 21:09, 31 October 2008 (UTC)

I think a cookie is set if you click the link "Go to Google.com" at the bottom-right of the homepage. In the future you should get to google.com when you type google.com... —Preceding unsigned comment added by 82.124.209.97 (talk) 21:19, 31 October 2008 (UTC)

Thanks for the help. --Crackthewhip775 (talk) 21:46, 31 October 2008 (UTC)

If you can't get any of that to work, I'd suggest two things you could do: 1. You could put a link to google on your bookmarks bar, or you could also just set it as your homepage if you wanted to just access it from there. At least on the older versions of firefox (such as firefox 2) you could change your bookmarks and change the keyword to google or google.com and then when you type that in the addressbar, it would redirect to the bookmark, which you could set as google.ca. I think it rather just appears in the dropdown menu and you can't just type and press enter anymore, but I'm not sure. Yakeyglee (talk) 23:28, 31 October 2008 (UTC)

where do people learn Oracle?

so Oracle is huge, but computer science programs dont include it much, it's not a slashdot topic, etc. so where do all these Oracle dba's come from? —Preceding unsigned comment added by 82.124.209.97 (talk) 22:11, 31 October 2008 (UTC)

They learn on the job. You can learn about databases in a computer science program but that'll be about how they actually work - eg "how exactly do you implement indexing of a table", interesting stuff with broad relevance. What a DBA needs to be able to do is more practical, and the knowledge required would not be interesting or worth learning outside of a business context, eg "where should we apply connection pooling first to improve performance". It's not something that you could teach outside of the workplace. And would be very boring if you tried. —Preceding unsigned comment added by 90.217.161.173 (talk) 18:08, 1 November 2008 (UTC)

You can take courses from Oracle itself. See a list here. I imagine most people going this route are probably sponsored by their employers. TresÁrboles (talk) 19:44, 2 November 2008 (UTC)

There are also some colleges/universities offering Masters degrees in Database Systems (e.g. Westminster in the UK), and others which offer a more general Masters in the computer science department called something like Information Systems, which may include a significant component on database theory, SQL, and one or more popular database systems. Some people may take these while in employment but Information Systems courses seem quite popular among young people just out of uni. The exact database you use may vary - though Westminster does use Oracle, others may use the cheaper MySQL - but the basic principles are the same.

As an aside, I've noticed that a lot of institutions are shy of using the word "database" in their prospectuses, probably because of the reputation for boringness - despite the centrality of databases to many fun internet applications, even Wikipedia. Also, you have to watch because Information Systems can be confused with Information Science, which is more for librarians.--Maltelauridsbrigge (talk) 14:44, 3 November 2008 (UTC)

Google

I'm surprised that Google did not have a Hallowe'en logo on their front page. Why didn't they? 124.180.143.48 (talk) 22:16, 31 October 2008 (UTC)

I could have sworn they had one up earlier! (At least on google.ca) . Can anyone else confirm? They might have felt great Christian backlash... :) —Preceding unsigned comment added by 82.124.209.97 (talk) 22:21, 31 October 2008 (UTC)

They have one up for me. Here's the link. --98.217.8.46 (talk) 23:11, 31 October 2008 (UTC)

They sure do have a Halloween logo on the front page; how long ago did you check it? Yakeyglee (talk) 23:24, 31 October 2008 (UTC)

They emphatically don't for me right now (four tildes = 82.124.209.97 (talk) 23:48, 31 October 2008 (UTC) ). Is it because I'm geographically in France? In every browser, no matter how I load the English www.google.com, I can't get to a halloween picture :(. GOogle have RUINED halloween for me...

Maybe it's because it's November 1 in France already? --98.217.8.46 (talk) 00:11, 1 November 2008 (UTC)

Yep - I'm still seeing it here in Texas at 10:45pm local time. SteveBaker (talk) 03:45, 1 November 2008 (UTC)

I was playing around with URL's and tried http://www.google.us which redirected to http://www.google.com/webhp. Perhaps the latter is a nonredirecting portal. I'm in the US, so I can't tell. -- Tcncv (talk) 04:09, 1 November 2008 (UTC)