Wikipedia:Reference desk/Archives/Computing/2010 July 14

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July 14

Custom persona will not stick

I finally succeeded in creating my own Firefox persona (see several questions above), but now I have another problem. It won't stay. What I mean is that I keep clicking "apply" in the Persona menu, but it either never checks or it reverts right back to the previous persona I had after two seconds. How do I fix this? 24.189.88.30 (talk) 00:59, 14 July 2010 (UTC)

Using ogis2svg.pl

I'm trying to use the ogis2svg.pl class to convert the US Census shape file of the entire United States into svg format. I'm using Ubuntu 10.4 x86, and for compatibility I've installed libmath-round-perl, postgresql, postgresql-client, postgresql-contrib, pgadmin3, and postgresql-8.4-postgis. But I get the following error during compilation:

converting shapefile to a temporary sqlfile ...Shapefile type: Polygon
Postgis type: MULTIPOLYGON[2]
unknown error with conversion from shape to temporary sql file!

Mind you it still puts out a lot of valid sql before it aborts. What am I doing wrong? The postgis version is above what's required by the ogis2svg page (8.4 vs. 8.2). Note: I've also tried a workaround under Windows XP in Virtual Box, but I get an unrelated error there which appears to be related to poor compilation of the executable, so I've abandoned that route. Magog the Ogre (talk) 01:06, 14 July 2010 (UTC)

CPU cooling

I recently bought an i7-860 which came with a fan, but I wanted opinions on whether this standard fan is sufficient or if I should buy something else, and if so, what is a good choice? The reason I ask is that I think the fans fuse on after some use, and can't be taken off again. For context, it does get very hot in summer (Southern Australia) but it's a case with fairly good airflow. Benjamint 02:04, 14 July 2010 (UTC)

If it's an Intel stock cooler, it most definitely should be sufficient for normal usage (meaning no overclocking although even mild overclocking and overvolting is usually fine, the HSF should have sufficient headroom) since if not it would be defective/unsuitable and Intel shouldn't be providing such things. If it's not a stock cooler (if it came in a retail box it should be) then there's a chance it won't be although I doubt it. Also removing the HSF should be possible unless you plan to apply thermal glue. The thermal pad that comes with the HSF is a bit waxy and can stick somewhat but you should still be able to remove the HSF, particular if you do it while warm (in other words, if you ever want to do it consider turning on the computer and loading the processor for a while before you try to take it apart). If you are concerned, considering removing the stock thermal pad and applying some sort of thermal paste like Artic Céramique or Artic Silver which isn't sticky (bear in mind these are sometimes not officially supported by Intel) and then you should not have any problems removing the HSF if you ever need to. Nil Einne (talk) 04:29, 14 July 2010 (UTC)

Thanks Benjamint 07:50, 14 July 2010 (UTC)

TV Tuner Card/Signal Issue

Resolved

I have a TV Tuner Card in my PC. I'm not sure its name or how to check but it came default in my computer when i bought it. I used it for a year at college to watch/record shows from cable with windows media center, so it should work? When i came home for the summer i plugged in the antenna with a coaxial cable to watch public TV (air waves) I believe we have a digital antenna, but despite my going through auto detect on media center (cant find signal) and manual setup (tried every option available to choose from, still no signal) i cant get it set up!

My dad insists that the antenna is hooked up to the wall box up here, but since the place where i can supposedly check is dangerous (an unfloored attic space) i would like to see if i can look at the raw data from the coaxial cable before coming to the conclusion that we need to fix our hookup. (Bringing a huge flat screen TV up here, which is all we have, is also complicated)

Does anyone know of a program that would be able to show me raw data from the tuner card? i just want to see that i am in fact getting a picture, and figure whether its media center/my PC that's goofy or if it is in fact the coaxial hookup.

Thanks! 63.26.247.76 (talk) 03:30, 14 July 2010 (UTC)

ADDITIONAL: I did look on the back of my card and there is a "TV" and "ATSC" hole. i did look up some stuff on ATSC and found that that is a digital signal, however my coax cable doesnt fit there, i would think i could still grab my signal through coax?

63.26.247.76 (talk) 03:44, 14 July 2010 (UTC)

Which version of Windows are you using? What model is your TV tuner card? And what do you mean by your coax cable will not "fit" in the hole? You will need to connect to the ATSC input because the U.S. shut off analog broadcasting last year and is now exclusively broadcasting in digital. The tuner card worked at college because most cable TV systems still carry analog signals. Many TV tuner cards have separate inputs for analog and digital signals. PleaseStand ^(talk) 03:58, 14 July 2010 (UTC)

Wow! I feel dumb! What i mean i guess by doesn't fit is that i guess for whatever reason the hole for the pin was either really snug, or it felt like there was something blocking the hole or it was the wrong configuration on the inside. I came to this conclusion because the pin, like many coax pins after a while, was bent and i didn't want to accidentally break it. After reading your post i tried again (with a little more force!) and it went in and all works like a charm, silly me! Anyway you have my thanks for the help, this has been bugging me for a while!

63.26.247.76 (talk) 05:13, 14 July 2010 (UTC)

Hard Drive

If I reformat a hard drive will it erase all the sensitive information on it?75.185.120.28 (talk) 04:19, 14 July 2010 (UTC)

No. You need to write data over it. Formatting doesn't do that, it just rewrites key areas of a drive. Even after writing over data, it's possible (but not probable) that someone could continue to recover data. Others can provide the links to that (I know we have some). Writing zeros over all of the drive is a very good approach, and writing random data first, then zeros is even better. Shadowjams (talk) 05:16, 14 July 2010 (UTC)

(ec) To the casual observer, yes. To a determined forensic examination, no; see data remanence for more details. Of course, if you put that drive back into regular use, the new data will eventually erase all trace of the previous contents. There are specific software utilities that can erase data more thoroughly, usually by repeatedly writing zeros, then ones, then zeros, then ones, etc. to the drive; see Data erasure for more info. Astronaut (talk) 05:33, 14 July 2010 (UTC)

As mentioned in the data remanence article, there's no evidence that anyone in the world can recover data that's been overwritten just once. Unless you're such a dangerous criminal that the U.S. government is going to use classified NSA technology on you—in which case you're probably doomed anyway—don't bother with fancier overwriting schemes. A "quick format" will not overwrite the whole drive, but I think a "full format" will; but I'm not certain that that's true in 100% of cases. It's better to use a dedicated data-wiping tool, of which there are many. -- BenRG (talk) 20:00, 14 July 2010 (UTC)

Another non related hard drive question

Is it possible to make a create a new partition out of unused space on a existing partition? For example I have a 500 gb hard drive. It is split up into C and D. There is data on both drives already. I want to create a new partition out of the unused space on D and call it F. Is that possible without having to reformat D completely? 75.185.120.28 (talk) 04:29, 14 July 2010 (UTC)

Yes, but it's tricky and if it goes bad it can mess up your pre-existing data. Backup everything before you try anything. For windows there are a few programs, but Norton Ghost I think has that option. On *nix or mac, you can try (may need to install it) gparted, which is pretty good at these kinds of changes, but again, it's risky. Shadowjams (talk) 05:14, 14 July 2010 (UTC)

Yes. It is easy to do so long as you don't use Window's default disk partition utility. There are a number of other disk partition utilities that will do this without destroying the data on a partition. My choice would be to boot my PC from a Linux Live-CD and run GParted to shrink the second partition (probably called /dev/sda2). That would make space so GParted can make a new partition and format it. Once you go back to Windows, the new partition will just appear, probably as drive E (and the CD/DVD will become drive F). When messing with partitions, it is a good idea to take a backup in case something goes wrong. Astronaut (talk) 05:15, 14 July 2010 (UTC)

Stay away from Partition Magic! I agree with gparted, it seems to be the best and most stable. Just be very careful, it's really worth it to backup even though you might think you know what you're doing. Sandman30s (talk) 07:22, 14 July 2010 (UTC)

RAM buses

if buses is the right word, I'm just curious what kind of limit there is on "bandwidth" of transmission to and from a stick of RAM, i.e., what is the bandwidth of the connection accross the motherboard to the cpu. And, if forexample you used 2 4GB sticks, is it possible that you wouldn't get quite as good performance asif you used 4 2GB sticks because of this "bandwidth" limitation? (Corsair DDR3 C8 1600, and the motherboard is an Asus P7P55D-E) Thanks, Benjamint 07:54, 14 July 2010 (UTC)

Yes, but it depends on your motherboard configuration. Modern RAM uses a channeled system with one or more memory controllers, so depending how you connect RAM to these channels, your peak- and average- throughput will vary; and if you use a very modern computer, with QuickPath Interconnect, there is an entirely different memory architecture. Ultimately, the bandwidth limitation boils down to a very simple equation: how many wires connect Point A to Point B; and how fast can each wire transmit digital data without corruption. But this is a bit over-simplified, because modern computers do not have only bidirectional memory access - DMA devices, including multiple clients that are attached to the CPU and its cache, (and of course, multiple cores and muliple CPUs) may all be requesting simultaneous memory transactions. For these reasons, QPI (the newest memory connection architecture from Intel) functions more as a "network arbiter" than a simple memory bus. In terms of raw numbers: today's best systems will sustain on the order of 4 to 8 giga-transfers per second; each transfer would usually be a 64-bit or 128-bit cache-line (though it may be smaller for some processors). Here's "Weaving High Performance Multiprocessor Fabric", from Intel. Nimur (talk) 17:54, 14 July 2010 (UTC)

Microsoft

is IIS 6.0 & MDAC part of MS SQL Enterprise Server 2008 R2 license or do we have to purchase it seperately —Preceding unsigned comment added by 78.93.67.27 (talk) 09:58, 14 July 2010 (UTC)

IIS is usually bundled with the operating system and just needs to be enabled. Certain versions of Windows do not include IIS, but if you have Windows Server, it is probably already installed and just needs to be enabled (instructions). MDAC is available as a free download from Microsoft. Nimur (talk) 17:47, 14 July 2010 (UTC)

Hands-free (Bluetooth) for home phones

When shopping for a cordless phone, I see that some are Bluetooth-enabled. I don't understand how this works. Apparently, I must have a mobile phone in order to take advantage of the feature. I don't like buying things and bringing them home just to find out how they are to be used, and store employees don't know much. Can someone tell me the protocol for using Bluetooth for home phone use? I keep destroying expensive headsets, by catching the cord on things. Thanks! --Everything Else Is Taken (talk) 15:00, 14 July 2010 (UTC)

I don't have the answer but the obvious one is to shop somewhere where the assistants actually have decent product knowledge. Exxolon (talk) 16:41, 14 July 2010 (UTC)

I'd love to, but I live in a technological backwater. --Everything Else Is Taken (talk) 00:32, 15 July 2010 (UTC)

It looks like you pair your cellphone with the cordless phone system, just like you would with a Bluetooth wireless headset. That way, when somebody calls either your cell phone or your landline phone, the cordless phone would ring and you could just answer it. See this article for more info. Indeterminate (talk) 18:12, 14 July 2010 (UTC)

Ah. I did read the article; thank you. I think I'd misinterpreted the whole phenomenon. I'm looking for a way to talk on my home phone, on a headset, without dragging a cord around. It looks like what the market has demanded is something entirely different -- going from the convenience of hands-free and cordless to the need to hold the phone or use a corded headset. Oy. Definitely not what I'm trying to achieve.

It's just weird -- I can't understand why the market doesn't support what I'm looking for; don't other people want the convenience of a hands-free cordless phone at home? --Everything Else Is Taken (talk) 00:32, 15 July 2010 (UTC)

A quick online search for "hand free cordless phone" revealed a large number of results that seem to be exactly what you're looking for. --LarryMac | Talk 10:45, 15 July 2010 (UTC)

What is the best (free) tool to convert .avi to animated Graphics Interchange Format?

Please tell, and from where I can download it ? -- Jon Ascton  (talk) 18:31, 14 July 2010 (UTC)

There are many free programs that can make gifs, I'm not sure which is the best. GIMP is one option, here is a quick guide. You could also try iWisoft Free Video Converter which I've found to be very easy to use, but there isn't much advanced control over the gif settings so they sometimes end up choppy or very large. Other free programs you could try are mencoder, SUPER and FFmpeg, however in my experience these are slightly less intuitive to use, especially for a beginner. My personal method for making gifs is to take snapshots of the video with mplayer, then use 'Ulead gif Animator' to make the images into an animation. However, that program isn't free, but if you're just making a one off gif the trial version is fully functional for 15 days after install. 1230049-0012394-C (talk) 22:31, 14 July 2010 (UTC)

Bing Search products not found. Do they exist?

The Wikipedia article on the search engine Bing <http://en.wikipedia.org/wiki/Bing_%28search_engine%29> includes a table listing ″Search products", one of which is "University". When I open www.bing.com, I cannot see this service on offer. Clicking on "More" brings up a list of services *Web*, *Images*, *Videos*, *Shopping*, *News*, *Maps* and *xRank*, but nothing more. Searching (using Bing) for "Bing University", "Bing Services" (and other combinations) does not seem to bring up the right result. The bing website does not seem to elaborate or give any helpful information either. Does this service exist? Is it restricted to the usa only*? How do I get to this service?

• There are others in the world who use the internet, I am located in germany! Does that make a difference?

PS: I have not placed links for each step, as these may display differently depending on viewer location.84.130.121.37 (talk) 17:00, 14 July 2010 (UTC)

I couldn't find it either, and the cited reference for the entire section was to a bad URL; so I placed some "failed verification" tags next to each use of that reference in the Bing article, and I went ahead and removed the "University" line. There is a Bing site called "discoverbing.com" that does talk about a bunch of Bing features (though I didn't find the alleged "University" feature). Comet Tuttle (talk) 17:12, 14 July 2010 (UTC)

Renaming clashing files before copying in Windows batches

I would like to copy a file from folder A to folder B, but if a file of the same name already exists in folder B, then I would like to automatically rename it eg from myfile.exe to myfile01.exe before copying. Is that possible with a Windows batch file please? 92.28.246.39 (talk) 19:01, 14 July 2010 (UTC)

Yes, this is possible. You can check if a file exists (or does not exist) using the IF EXIST syntax. You can design logic to either increment a number or append a new tag until you have a unique file-name that does NOT exist. Here's the most trivial example, note that this will blindly overwrite any pre-existing backup file, so use with caution or add some additional logic to check:

IF NOT EXIST %destfile%    copy %srcfile% %destfile%
ELSE copy %srcfile% %destfile%.bak

Nimur (talk) 20:22, 14 July 2010 (UTC)

Thanks, is it possible to manipulate/edit the filename more? Thanks 92.28.246.39 (talk) 21:27, 14 July 2010 (UTC)

Yes, what more would you want to do to it? You could construct a "while loop" using the GOTO command:

 set srcfile=input1.dat
 set destfile=output1.dat

 SET num=0
 :renameLoop
 SET /a num=num+1
 SET newname=%destfile%.bak%num%
 IF EXIST %newname% (
  GOTO renameLoop
  ) ELSE (
  copy %srcfile% %newname%
  )

(Note, I haven't tested that much). You can perform arbitrary manipulations; if you want to get really fancy, you'll soon see that DOS BATCH is a really clunky toolkit and I recommend you consider a more suitable language like Perl or Python for advanced filename manipulations. Nimur (talk) 23:18, 14 July 2010 (UTC)

Thanks very much for that. I was thinking of something like myfile.jpg to myfile001.jpg, or if that is not possible then something like myfile.jpg.001.jpg Thanks 92.24.191.1 (talk) 11:51, 15 July 2010 (UTC)

That %num% substitution can be used anywhere in the file name, but you would have to split the extension away for it to work the way you intend. Simple windows scripting (without powershell) can get tricky on accomplishing this. I fould a fairly helpful document on Scribd but since Scribd makes me want to gouge my eyes out with how terrible their site works, I will have to pass on investigating this further. --144.191.148.3 (talk) 15:46, 15 July 2010 (UTC)

Exactly - such string-substitution of the %num% into the middle of the filename can be done, but it will be horrible. DOS batch doesn't make text-processing very friendly at all - you really want some tool that lets you directly manipulate the filename strings, or operate on regular expressions. BATCH has a limited capability to do some such string substitutions, and if you wanted to get really messy, you could roll your own text-processing routines, but it would be better to use a more powerful scripting tool. Nimur (talk) 18:40, 15 July 2010 (UTC)

Word Search

July 14 2010 To Whom

I was trying a recipe into my cookbook program & have used your site to look up a lot of words for food I did not know what they where. Today I was doing the same & came across this ingredient called Bijol powder I went to your site & there was nothing for this item. I am not sure what to do so that is why I am e-mailing you. If you are able to find out what this is, it would be a great help to me. Your site has helped me out in so many ways. I just wanted to let you know how happy I am that I found your site. Thanks for your time with this.

Again thanks Michael A. Velto <personal contact details removed> —Preceding unsigned comment added by 72.220.231.73 (talk) 19:03, 14 July 2010 (UTC)

See Bixa orellana which explains its uses and alternate names. Nanonic (talk) 19:25, 14 July 2010 (UTC)

Broadband availability

I'm going to start house hunting in London next week and, being an internet addict, one of the factors I would like to take into account is the availability of super-fast broadband connections. Is there an easy way to find out what places certain options are available (as opposed to finding out whether a particular option is available in a particular place)? --Tango (talk) 19:03, 14 July 2010 (UTC)

What do you consider Super-Fast broadband? 1.5 MBps should be available almost everywhere in an urban environment like London. 10MBps may be available for a higher rate. 100 MBps and above will require commercial-grade connections and might be prohibitively expensive anyway, even if available. Nimur (talk) 21:42, 14 July 2010 (UTC)

Well, what I'm really looking for is information about a range of options. It's only one of many factors involved in choosing somewhere to live. I don't have an absolute minimum speed I'll accept, I just want to know where has what speed in order to help me narrow down general areas to consider. --Tango (talk) 22:18, 14 July 2010 (UTC)

http://www.whitefence.com/ http://www.dslreports.com/ --mboverload@ 01:18, 15 July 2010 (UTC)

Neither of those sites seem to contain an answer to my question... --Tango (talk) 18:28, 15 July 2010 (UTC)

Does SamKnows ([1]) provide any help? --Phil Holmes (talk) 21:20, 15 July 2010 (UTC)

It's the best site I've seen so far - thanks! --Tango (talk) 17:44, 16 July 2010 (UTC)

Quick help with a Joomla task

I am helping someone set up a site with Joomla. This is the first time either of us have used this management system. We are using the "rhuk_milkyway" template and want to delete the dropdown menu that changes how many news items are visible at a time, since we got rid of the news items idea all-together.

I have looked in "Edit HTML" and "Edit CSS" parts of the template manager, and it looks very cryptic. I JUST want to get rid of the dropdown menu that has "5, 10, 15, 20, ... , 100, ALL" in it. Any ideas what lines i should erase or where i should do this?

Thanks! 71.221.23.60 (talk) 19:27, 14 July 2010 (UTC)

Microsoft Excel

This question is about Microsoft Excel syntax. Let's say I have a spread sheet that records each employee's working hours throughout the week. Each employee had his own row on the spread sheet. I want to add up certain cells on a given row, so I type =sum(B1:H1:J1) for my employee on the first row and this will sum the entries in cells B1, H1 and J1. I want to do the same for the next employee on row two, so I have to type =sum(B2:H2:J2). Similarly for the third employee on the third row; I type =sum(B3:H3:J3). But what if I have 1,000 employees? Do I have to type 1,000 little formulas by hand? I want a command like =sum(B[row number],H[row number],J[row number]) so the spread sheet will substitute [row number] for the row number. So pasting into row one gives =sum(B1:H1:J1), pasting into row two gives =sum(B2:H2:J2), and pasting into row three gives =sum(B3:H3:J3). Any ideas? •• Fly by Night (talk) 20:49, 14 July 2010 (UTC)

Your formula looks a little odd. If you just want to add cells B1, H1 and J1 then the formula is "=B1+H1+J1". "=SUM(B1:H1)" means the sum of all the cells from B1 to H1 (so B1+C1+D1+E1+F1+G1+H1). I'm not sure what it would mean to have two colons in a formula like that. That doesn't answer your question, though. Repeating a formula while changing the cell references is easy: Type the formula in the first row and hit "enter", then select that cell. It will now have a black outline round it with a black square at the bottom right. Click that black square and drag it down to the last cell you want to have the formula in it. It will fill in the formula and change the cells references so they have the same position relative the the cell with the formula in it (so if your original formula refers to cells in the same row as the cell with the original formula in then the new formula will refer to cells in the same row as the cell with the new formula in). For future reference, if you are using this technique but want to keep some of the cells the same, you can write "&A&1" or, to keep the row the same by allow the column to change, "A&1" or, to keep the column the same and allow the row to change "&A1". --Tango (talk) 21:11, 14 July 2010 (UTC)

You're right, I should have used commas instead of colons. I used the right notation in my general formula: =sum(B[row number],H[row number],J[row number]). •• Fly by Night (talk) 18:19, 15 July 2010 (UTC)

(Actually it's $, not & for absolute references. You're some kinda C programmer or sumthin'.) Comet Tuttle (talk) 21:19, 14 July 2010 (UTC)

I was doubting myself as I wrote it. I blame the font in the textarea - both looked wrong and I ended up picking the wrong one. Sorry for the mistake and thanks for the correction! --Tango (talk) 22:30, 14 July 2010 (UTC)

(ec) 1. Actually you would use =b1+h1+j1 if it were 3 individual cells, rather than the colons; colons in an Excel formula mean "everything from this cell to this cell, including all cells in between." 2. You don't need to type 1,000 little formulas by hand, but you don't need a special formula. Here's how: (a) Put your =b1+h1+j1 statement on the same row as the employee's working hours — let's say it's in cell Z1 — and hit Enter. (b) Using the mouse, drag from Z1 down to Z1000. (c) Hit CTRL-D (for "down"). (d) Examine some of the cells manually. You'll notice that Excel has predicted what you want to do, and has filled in all the cells with "relative" (as opposed to "absolute") cell coordinates. Does that work? Comet Tuttle (talk) 21:18, 14 July 2010 (UTC)

Thanks Tango. I tried it, and it worked perfectly! •• Fly by Night (talk) 18:23, 15 July 2010 (UTC)

And if you don't like dragging the formula all the way through 1,000 rows, you can also just double-click on that same little box and Excel will automatically insert your formula all the way down, provided there's data in the column beside the one you're working on. I use gi-normous Excel sheets all the time and love this function. Matt Deres (talk) 20:15, 15 July 2010 (UTC)

delete

how can i delete files without them going to the recycle bin? —Preceding unsigned comment added by 77.70.66.110 (talk) 22:11, 14 July 2010 (UTC)

Hold the shift key while deleting [2] 1230049-0012394-C (talk) 22:13, 14 July 2010 (UTC)