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September 9

LG TV that can turn all 2D images into 3D ?

That is their claim. Call me skeptical (SkepticalRat ?). I don't see how this is possible with current technology. I suppose, using some advanced artificial intelligence, by recognizing each object, judging their relative sizes (versus their absolute size, other object's relative sizes, and this object's size in surrounding frames), overlap, focus, etc., a highly advanced program could determine which objects are in front and which are behind, and then render them accordingly, but somehow I doubt if this is what they do. So, what exactly do they do ? StuRat (talk) 04:19, 9 September 2012 (UTC)

Wikipedia's 2D to 3D conversion article seems to link some useful references. -- BenRG (talk) 05:13, 9 September 2012 (UTC)

Interesting links, but have I missed one that explains what StuRat is asking? I share his skepticism. Dbfirs 07:09, 9 September 2012 (UTC)

... Hmm ... it looks as if I'm wrong[1], and these TVs really do some very clever image recognition and lightening-speed processing. They must contain extremely fast processors and a lot more computing power than the laptop on which I am typing this reply! Dbfirs 07:20, 9 September 2012 (UTC)

To quote from the above linked page: "Conversion software looks at the content and performs analysis of its shapes and colours, works out what's in the foreground and background, and then creates a map of the images to create two slightly different versions giving the parallax image our eyes need to receive to 'see' in 3D. Of course, the software is so powerful that it completes all of this at super fast speed. To summarise, what 3D TV conversion software is doing is modifying the depth of field of a 2D image to render it in three dimensions."--Shantavira|^{feed me} 07:58, 9 September 2012 (UTC)

OK, so is it any good ? I picture it working about as well as the first attempts to change black and white TV into color, where they colored the bottom third green and the top third blue, hoping that would be right at least part of the time. StuRat (talk) 14:24, 9 September 2012 (UTC)

Confirming my skepticism, the article says "...it can suffer from a lack of clarity and sharpness. Quick image movements on the screen can also [be] blurring or stuttering." StuRat (talk) 14:38, 9 September 2012 (UTC)

The quality is so-so. At the best it looks like something you would see in a View-Master. There is a perceived depth of field but everything looks flat like in a View-Master. We've had the TV for about a year but other than the first week we haven't used the conversion since. Proper 3-D films look fine on it. CambridgeBayWeather (talk) 02:17, 10 September 2012 (UTC)

OK, thanks, that's good info. It looks like this idea is literally "not ready for prime time", so I won't purchase one until they improve the technology. StuRat (talk) 16:13, 10 September 2012 (UTC)

Which CD/DVD?

I'd like to copy some of my MP3s onto a CD to play in my car stereo. But I'm not sure which formats to use. I have a few questions:

• All of my songs are on iTunes. Can I write to CD/DVD from iTunes?
• My laptop has a DVD-RW on its disk drive. Which CD/DVD formats can it burn?
• Would my car stereo be able to play DVDs containing music files?

Hopefully you'll be able to shed some light on this, or tell me what other things I need to know to be able to answer these questions. — Fly by Night (talk) 13:48, 9 September 2012 (UTC)

1. yes
2. you want to burn Red Book (CD standard), nothing else, on a CD (not a DVD)
3. car audio tends to be much less flexible and forgiving than even the cheapest computer. Some of the fancier lines of car audio, like Sony's Xplod and Philips' Expanium are more likely to play mp3s and to tolerate different formats, but the stock equipment many cars shipped with can be much less flexible. You'll have to burn some samples to see - make sure you start with a CD-audio project on CD-R media with only an hour of music, and once that works in your car you can experiement to find its limits.

-- Finlay McWalterჷTalk 13:56, 9 September 2012 (UTC)

I should qualify the first as perhaps "maybe". I've done it, in iTunes, with audio ripped on that machine - as I've never bought music online, I don't know whether iTunes will let you burn that to disk. -- Finlay McWalterჷTalk 13:58, 9 September 2012 (UTC)

I must say, my advice would be not to bother, but instead to rig up a cable to your car's stereo's AUX port (which most have, buried away somewhere). If you're not happy doing that yourself, any car audio installer should be able to run a cable with either an iPod or 3.5mmTRS connector, allowing you to use any digital audio player through the car's audio system. -- Finlay McWalterჷTalk 14:07, 9 September 2012 (UTC)

Yes, I used the AUX port for many years until I bought a (second-hand) car with a CD player that claimed to play MP3s. To my surprise, this worked, though it can't cope with more than 255 tracks in any one folder, so I create several folders. I have CDs with many hours of music in MP3 format, and the car CD player just chooses tracks at random, starting to play as I switch on, and continuing from the exact place it stopped last time. I find this much more convenient than the AUX input, and I don't need to change CDs. I've never seen a car CD player that can play DVDs of music in MP3 format. Dbfirs 15:33, 9 September 2012 (UTC)

More convenient how? :/ ¦ Reisio (talk) 16:58, 9 September 2012 (UTC)

The ideal thing would be an automotive-grade audio device which takes removable high-capacity solid-state media like Secure Digital. There are some downsides of using a portable player like an iPod and an AUX connection: the haptic-UI and high-contrast display of automotive audio equipment is easier and safer for drivers to use (a touchscreen is difficult to use when you're driving and can't look at it); automotive components have a wider range of temperature tolerance than consumer components (which is an issue for people in Arabia or Canada); and simply having the system built in (and not dangling on a cable) is neater and makes it harder to steal. There are plenty of such players available from the usual aftermarket car audio manufacturers, but they don't ship this on most cars in the base to middle of a range. -- Finlay McWalterჷTalk 17:17, 9 September 2012 (UTC)

The answer depends on the stereo in your car. The options are

• You have a basic CD player that can handle CDRs (most modern players should handle this). In this case you 'll need to burn a cd as an audio cd, and you'll be limited to about 80 minutes of audio.
• You have a CD player that handles MP3s. Look for the MP3 logo on the player. If this is the case you can burn a data CD of the mp3 files. You can store 10 hours or more of audio this way on one CD.
• You use an auxiliary jack and hook up another device (like an mp3 player) to it with a simple phono cable (you can buy one at radio shack for $6).
• You have a player in your car that accepts another media, like an SD card or a usb drive, in which case you can put files onto that and play them off of it. Mostly you'll find these in aftermarket stereos and not original ones. Shadowjams (talk) 18:14, 9 September 2012 (UTC)

Another option: fancy cars (or cars with fancy kits) have iPhone docks, which allow iPhones to play through the stereo, and makes the car the iPhone's hands-free kit . I think this doesn't work for Android or Blackberry phones, as they don't have the docking connector with all the additional connections that makes this work. 146.90.59.151 (talk) 01:58, 10 September 2012 (UTC)

Many newer cars (in the last couple of years) that are available in the UK have an aux port for the car stereo. Read the manual or have a fiddle around with the 'source' control to establish whether there is an aux port at all (it will probably give a choice "radio/CD" or "radio/CD/Aux"). The port is occasionally on the front of the stereo, often in a space near the cigarette lighter (or power jack), but it is sometimes hidden in the armrest. If you have an aux port, any old MP3 player can be connected to it. It can be distracting to play with the MP3 player while driving, and watch out if the MP3 player is also your phone, you might be accused of "using" your phone while driving (a £60 fine and 3 penalty points on your license).

CD players on the other hand have no such restrictions. Burn MP3s onto a CD-R using "audio CD" as the output media. This will give you the best chance of compatibility with the CD drive in your car stereo.

DVDs? No chance, unless you have one of those video things to keep the kids busy on long journeys. The screens are designed to only be hung on the backs of the seats, so the images don't distract the driver. Astronaut (talk) 10:38, 10 September 2012 (UTC)

Video streaming is slow, especially in youtube

Hello there, I am having trouble in streaming video in youtube.com for last couple of months. As for other websites, this problem happens occasionally. I do not have problem with browsing and downloading though. If I pause a video while it is streaming, the streaming usually gets stopped at the middle of playbar. But if I press play button with mouse pointer then streaming continues. Why is this happening? All I want is, video will be streaming while I pause the video so that I can continue watching video after streaming is over. I have updated Mozilla browser along with latest Java and adobe flash player. But nothing happened so far. The problem remain same. Am I missing something or should I change any settings? Thanks--180.234.35.56 (talk) 17:39, 9 September 2012 (UTC)

There are a few sites that suggest fixes on your pc, like http://www.delete-computer-history.com/slow-streaming-video.html or if you have access to google groups maybe this (don't have access myself, so it may be useless for all I know). Found a tip about DNS servers. I had similar problems with video, downloading files etc... a while ago; most likely a cable fault somewhere between my pc and the router, fixed itself after a week, sparing me the trouble of breaking open part of the floor... You could also google to see if other users using the same ISP have similar problems, maybe they put a limit on video streaming bandwidth. Ssscienccce (talk) 15:59, 10 September 2012 (UTC)

It may be that they are reluctant to allow you to download an entire video, then play it, as that makes it easier to copy than if you just stream it. However, as you noted, streaming often has problems, as it's one of the most demanding applications on a PC. It's possible the slow-down is at your PC, not on the Internet. Try a reboot, then don't start any other applications besides the streaming video. You might also try lowering the resolution and frame rate, if you have those options. Also, if you have the ability to play the YouTube video elsewhere, like on your TV or portable device, this will tell us if the problem is just on your PC or not. StuRat (talk) 16:08, 10 September 2012 (UTC)

It's not a problem on your computer, this is just how the YouTube Flash player works now. It only buffers a segment of the video at a time. If you pause, the buffer only fills part of the way. When you play, and the play position moves near the end of the buffered portion, it starts filling the buffer again. I noticed this new buffer behavior around the beginning of this year, but I don't remember exactly when. It might buffer differently on faster internet connections, but I don't have any to test with.

Here's something you can try: Disable the Flash plug-in in your browser. If your browser supports HTML5 video, this will force YouTube to use its HTML5 player. (If your browser doesn't support HTML5 video, you'll just get a message that Flash is required.) To get YouTube to use the Flash player again, you may have to delete cookies and re-enable the Flash plug-in. When I tested in July, YouTube's HTML5 player buffered the entire video when I paused. However, on my computer, the HTML5 player picture would intermittently freeze for a second while the audio continued. You might want to compare YouTube's Flash and HTML5 players to decide if this method is worth it for you.

Here are some other suggestions, but I haven't tried any of these: Force YouTube to always buffer the entire video before playing

In July, another poster here was trying to let the entire video play to fill the buffer, then press the restart button to watch the buffered video, but YouTube was still redownloading segments of the video. I found the URLs the YouTube Flash player was requesting had parts rearranged, causing the URL not to match the existing segment in the cache, even though the downloaded bytes were identical. (I suspect this was an oversight, I can't imagine why YouTube would want to send you the exact same bytes in your cache again.) If you're willing to wait the entire play time of the video you might test and see if the buffer remains on replay or if the bug still exists where it redownloads segments.

@StuRat: The new buffer behavior does prevent you from retrieving a single video file from the cache as you could previously. But I recently found NirSoft VideoCacheView can retrieve the entire video file from the cache. (Let the entire video play, find the newest item in VideoCacheView, then use the "Copy Selected Files To" command.) It seems the cache files are just in segments and only slightly difficult to re-combine. (The segments might overlap slightly so you have to examine the byte positions indicated in the URL to know how to combine them. And the beginning bytes are missing, so I guess you have to know some proper header bytes for the video format. I stopped investigating the details when I found VideoCacheView.) So I'm not sure if download prevention is the main reason YouTube changed the buffer behavior. A hypothesis I came up with is that YouTube doesn't want you to waste your bandwidth (or their bandwidth?) if you leave a video paused. For example, if you are watching YouTube on a mobile device this might be a legitimate concern? I haven't checked example bandwidths to see if this hypothesis makes sense. --Bavi H (talk) 02:33, 12 September 2012 (UTC)

I don't see why people would be going to such complicated arrangements if they want to retrieve YouTube videos anyway. There must be like hundreds of sites like KeepVid with Java applets or similar that allow you to input a Youtube link and then give download links for every quality available. There must be hundreds of other programs for Windows and at least a few for other major OSes which do similar. And unlike with other sites, Youtube rarely even breaks this. (Well with external site Java applets they could simply be updated so fast, unless you check for this. But with installed programs, you know they don't break if you disable any possibility of updating.) Many of these aren't open source, so you do have to trust them. But let's be frank, that's rarely a concern for most users, not to mention AFAIK Nirsoft stuff while useful isn't open source either. In other words, whatever Youtube is doing, they're clealy not putting much effort into stopping people retrieving whole files (some other sites do put a bit more effort).

To the original question, from my experience Youtube has been designed so the (Flash video) streaming stops after downloading a few extra minutes for a long time (I mean like two or three years at least). I suspect reasons for this include saving bandwidth for both the end user and Youtube. (Youtube may have a lot of bandwidth, but there must be many, many people who start a video then pause it either because it's boring of they want to do something else and never come back to it for whatever reason.) And a related reason would be to improve streaming on videos the person is watching. They may have recently reduced the amount it buffers before it stops, but I'm not sure of that. (With a quick test recently, I found with a few different files it only seemed to buffer about 30 seconds - 1 minute before stopping, IIRC, it used to do 3 - 5 minutes before stopping.)

If you want buffering to be complete, you can skip to near the end of the current buffer location as many times as necessary (you don't have to actually play) being careful to not go too far. (At least this used to work, but I haven't actually tested it in a while since my ISP stopped being so iffy with Youtube.) But in truth, if you intend to download the entire video before watching anyway, I suggest just use a tool to download it (whether an applet off an external site or something you personally download and run) rather then trying to convince Youtube to buffer the whole thing. (You can of course watch the video while it's downloading too if you have a player which doesn't mind if the file is in use like VLC.) That also avoids the problem where you may occasionally break the buffer which from my experience even when what I mentioned was working fine, could still happen on occasion.

Nil Einne (talk) 05:58, 12 September 2012 (UTC)

September 10

constructor inheritence in c++

Hello !why can not we inherit constructors in c++? i have read so many books.but i can not understand. can you please explain clearly? — Preceding unsigned comment added by Phanihup (talk • contribs) 00:58, 10 September 2012 (UTC)

C++ 11 supports constructor inheretance: C++11#Object construction improvement. Why not before? Because. 146.90.59.151 (talk) 01:55, 10 September 2012 (UTC)

'Transcluding' forum posts, possibly through RSS?

Would it be possible to transclude (using the Wikipedia definition) posts on phpBB forums, say, or even Yahoo! Answers on blogs like Livejournal, or anywhere at all with some code? (I was thinking about RSS since that's sort of how it works, but not sure if it could be transcluded in this manner.) 62.255.129.19 (talk) 03:20, 10 September 2012 (UTC)

Everything is possible: screenscraping is the ugly art of writing a program to grab contents of a web-page for programmatic use. If the source text is made available in a convenient, machine-readable format (like RSS), this greatly simplifies the necessary code. Nimur (talk) 04:09, 10 September 2012 (UTC)

Keeping external hard drive in case of a fire?

Will keeping an external hard drive in a fridge or freezer in case of a fire keep the drive safe? Or will the moisture or freezing temperature damage the drive? I'm asking about normal external drives, not special ones. Are you ready for IPv6? (talk) 04:25, 10 September 2012 (UTC)

Why do you think that a fridge or freezer would be fireproof? AndyTheGrump (talk) 04:33, 10 September 2012 (UTC)

(edit conflict)This forum thread goes over the second question. As for the first, I would think it depends on the severity of the fire. Dismas|^(talk) 04:36, 10 September 2012 (UTC)

Best is probably to keep a backup in a separate physical location (say, a safe deposit box, or your desk at work, locked in a drawer). If you're worried that others might gain access to these, make sure it's encrypted.

Of course it's a pain to keep it up-to-date. That's presumably why a lot of folks like to use cloud-based backup services. Personally I don't like that trend; I think it makes it too easy for the state to keep an eye on people. --Trovatore (talk) 07:47, 10 September 2012 (UTC)

They can already intercept your e-communications with arbitrary ease if they want to. Is there stuff on your hard drive that is more sensitive or telling than that? I sort of doubt it for most people. At least DropBox and most other serious services are encrypted, unlike most everything else you send through these here Internets. --Mr.98 (talk) 15:52, 10 September 2012 (UTC)

Dropbox may encrypt the data during transfer, but they hold the decryption key when it's stored on their service. So the Government can simply ask them for the decrypted data and Dropbox can provide it. Services/programs like Duplcati, Spideroak, Jungledisk encrypt the data on the client side before sending the data to the cloud. Therefore, only you have the decryption key and the service provider cannot access your data. - Akamad (talk) 22:28, 10 September 2012 (UTC)

Of course you can encrypt files yourself with something like PGP before you uplpad them to dropbox. Vespine (talk) 22:35, 11 September 2012 (UTC)

If it isn't convenient to use a separate location, (and you don't like "the cloud",) then a fireproof safe can be purchased at reasonable cost (less than the hard drive for a basic box). If you are expecting a fierce fire, then wrap it in (fibreglass, rock-wool) loft insulation for extra protection. Dbfirs 08:39, 10 September 2012 (UTC)

However, consider that fire is only one risk for the HD, depending on where you live these could include things like earthquakes, tropical storms etc which the safe may not definitely protect against. And while a fireproof safe may provide some protection against theft, you probably shouldn't rule it out either. I would suggest if you're trying to finds ways to ensure a single backup in the same location as the main data (I'm presuming we're at least talking about a backup here, not the sole copy of the data) gives a very high degree of protection against data loss, you're mostly wasting your time. Nil Einne (talk) 10:09, 10 September 2012 (UTC)

One trick that I rather like is finding a friend/family member in a similar situation and agree to "mututal backup" i.e. you each have a drive/partition or just some space on the other person's computer/file server etc. which you can use for remote backup. Programs like CrashPlan make this a viable solution even for non techy users. It's cheaper than the cloud (free if you do it yourself using e.g. duplicity and FTP, or are willing to accept the limitations of free versions of commercial backup software). If you choose your backup partner carefully you certainly trust your backup provider and on the security issue, just encrypt your data before sending. Equisetum (talk | contributions) 10:21, 10 September 2012 (UTC)

My solution is of course only free if you don't pay per MB for your internet access.Equisetum (talk | contributions) 10:24, 10 September 2012 (UTC)

A fireproof container could be built using soft kiln bricks or other fireproof insulation material. Temperature rise will depend on duration of the fire and the heat capacity of the contents, storing the drive in a waterproof container surrounded by a volume of water could help. To illustrate: suppose you use a hollow sphere (makes the calculation easier) inside radius 10cm, outside 20cm, made of material with an insulation value of 20 W/m.K. (based on the properties of cementitious foam) A temperature difference of 500°C gives a heat flow of 63 W or 63 J/sec; the inside volume is about 4 liters; if filled with water, temperature would increase 13.5° C in one hour. If instead of water, only an object with low heat capacitance is inside, say 1 kg of lead, then the temperature increase would be 29°C per minute. (ignoring air and heat capacitance of the insulation...). Not saying a DIY project is the best solution though... Ssscienccce (talk) 11:15, 10 September 2012 (UTC)

I know this is an anecdote, but I don't trust fireproof safes. I know someone who collected coins, and stored them in a fireproof safe. When his house burnt down, the safe survived, but the coins were a melted mess inside. A freezer certainly isn't designed to keep the contents safe during a fire. The seals would burn away when exposed to fire. I agree with the others that off-site storage is the way to go if you really care about the backup surviving a disaster at your home. 209.131.76.183 (talk) 12:36, 10 September 2012 (UTC)

Fireproof safes typically rely on evaporation of water inside the insulation to provide the rated protection of 30, 60, 120, 180 or 240 minutes. These materials can lose water over time, reducing the effectiveness. The test conditions for fireproof ratings vary from country to country. For example, the U.L tests leave the safe in the furnace to cool down naturally, the B.T.U. in Germany does the same. The CSTB in France and J.I.S. in Japan hose down the safe after the rated duration. And some companies may advertise their products as "tested to UL standards", even when they failed the test. Ssscienccce (talk) 15:26, 10 September 2012 (UTC)

Having been a volunteer firefighter in the US for about 15 years, I'll point out some additional risks. If the container is in a wood frame building, the floor may collapse in the fire, causing the container to fall to the basement. A substantial amount of water may accumulate in the basement; 15 cm would not be at all surprising. Also, in case of a disaster, the building and data may be undamaged, but the owner may prevented from visiting the building for an extended time. Jc3s5h (talk) 22:36, 10 September 2012 (UTC)

Thanks guys. So it seems if it's in a freezer with a plastic bag over it, it needs to stay in that to absorb the moisture till it thaws. Are you ready for IPv6? (talk) 03:12, 11 September 2012 (UTC)

My mom keeps important documents in a fireproof lockbox shaped like a briefcase (which has the added advantage of being easy to carry out of a fire provided it's in a convenient spot). My external drive would fit inside it fine. - Purplewowies (talk) 03:40, 11 September 2012 (UTC)

Gah. When building a house, avoid flammable materials like the Plague. If there ain't enough fuel to support a 2-hour fire, there ain't any need for a fireproof containment which lasts for 2 hours either. It all boils (burns?) down to the 3 Little Pigs. Oink. 217.251.166.157 (talk) 14:28, 11 September 2012 (UTC)

This problem is similar to the one I have been thinking about. I currently have two 1 terabyte external hard drives that I regularly back my system up to, but both of them are located in my apartment. A fire in my apartment would destroy all copies of my files. So I definitely need an off-site backup. I don't trust cloud back-ups, so I think buying more drives and storing them in a bank deposit box would be a good idea. From what I've asked over at the Finnish Wikipedia, rents for bank deposit boxes are in the order of less than 100 € per year, which is easily within my budget. The trouble might be in finding a vacant bank deposit box. Then there's of course the problem that even if the drive is safe from outside dangers, the mere fact that it's a physical object means that it's going to deteriorate over time. JIP | Talk 17:59, 13 September 2012 (UTC)

September 11

processing power vs clock speed

Hello, from the System/34 article: Clock speed of the CPUs inside a System/34 was fixed at 1 MHz for the MSP and 4 MHz for the CSP. In today's PC-based world, the S/34 was the computational equivalent of a 16 to 20 MHz intel 80386 microprocessor. How is this (same processing power at a fraction of the clock speed) possible? Thanks in advance, Asmrulz (talk) 00:46, 11 September 2012 (UTC)

One thing different is that it was a 16-bit system. Thus, it sends half as much data in the same time as a 32-bit system with the same clock rate and 1/4th as much as a 64-bit system. However, that would seem to lower the 1 MHz speed to 0.5 or 0.25 MHz equivalent, so something else must be going on. StuRat (talk) 00:52, 11 September 2012 (UTC)

That's a horrible article, with no citations. I'd support deleting the article and starting over.

As far as your question goes, I've never heard about control and main store on System/34. But I am familiar with how the terms were used on System/370 and System/390. Most or all of these systems were microprogrammed. Also, IBM didn't like to use anthromorphic language in any publications made available to customers, so what today is called memory was called "store" or "storage". The main store was the main memory, as with modern microprocessors. The control store held the microcode. Since the central processing unit used the microcode to interpret the instructions from the main store, it was necessary for the microcode to be retrieved at a faster rate (4 MHz) than the instructions and data from the main store (1 MHz). Jc3s5h (talk) 01:09, 11 September 2012 (UTC)

The article originally said (in July 2005):

In today's PC-based world, think of the S/34 as having the processor equivalent of two 20 MHz 486s

This was changed the following month, by User:Jessemckay, to read "... two 10 MHz 386s" and considerably later to the current version.

I agree the comparison seems dubious. I'll ask Jessemckay to comment here.-gadfium 02:35, 11 September 2012 (UTC)

7z and wikimedia dumps

I was astounded at the size savings between bz2 and 7z when compressing the Wikimedia dumps. The entire history bz2'd is around 450 GB while the 7z one is about 60 GB. That difference astounded me. Because the XML with the full history is not a series of deltas, but actually the entire page revision, I suspect 7z is doing some sort of processing to find the large blocks of identical text? One clue is the explanation from meta wikimedia says the 7z advantage is only on the full history dump, which indicates there's some advantage between full revisions (that's lost when you just dump current versions of the pages). But it seemed to me that the blocksize the compression works on would be far smaller than the span between two identical article revisions. Anyone who could shed some light on why 7z is so much better in this context would help. Thanks. Shadowjams (talk) 01:20, 11 September 2012 (UTC)

From the Lempel–Ziv–Markov chain algorithm article lead-paragraph, and its reference page, the 7z algorithm uses a dictionary whose size is up to 4 GB. That is considerably larger than some competitors, and is a probable factor. Nimur (talk) 01:47, 11 September 2012 (UTC)

bz2, 7z, and gz all look for repeated blocks of text, but 7z looks much further back. I don't think the window is anything like 4gb though, since the decompressor doesn't use nearly that much memory. 67.119.15.30 (talk) 04:44, 11 September 2012 (UTC)

Bzip2 divides the data into blocks of at most 900KB which are compressed independently. All other widely used compression algorithms are Lempel-Ziv variants using a sliding window. If there are N very similar page revisions each of length L, Bzip2 will re-encode the whole page text N·L/900KB times, while a sliding-window algorithm will encode it only once if the window is larger than L. -- BenRG (talk) 05:37, 11 September 2012 (UTC)

Thank you. I guess the sliding window answer makes sense for serialized data like this. My only follow up question is how the dictionary (which I gather is essentially the sliding window) does this work without using such a large amount of memory (4GB apparently). Tell me if this is correct: because the dictionary is not stored in memory and instead the index is, and it is accessed directly from the original file. Shadowjams (talk) 17:13, 11 September 2012 (UTC)

LZMA may support a 4GB window, but that would require 4GB RAM to decompress and a lot more than that (20GB?) to compress. I grabbed one of the smaller 7z dump files (3 GB uncompressed, 23 MB compressed!) and it uses method LZMA:24, which I think indicates a 16MB window (2²⁴ bytes). The gains from a larger window would probably be small since the longest article is less than 1MB. -- BenRG (talk) 19:09, 11 September 2012 (UTC)

According to the User manual, memory for compressing is 11 times dictionary size, memory for decompressing is close to value of dictionary size (limited table provided: dict - comp - dec: 64k-3M-3M; 1M-10M-3M; 16M-186M-18M; 32M-376M-34M ) Ssscienccce (talk) 19:50, 11 September 2012 (UTC)

…and the "ultra" (maximum compression preset) uses a 32M dictionary. Bonus points if you figure out how xz -9 compares. :) ¦ Reisio (talk) 01:37, 12 September 2012 (UTC)

I don't know what the user manual says but the 64 bit Windows GUI version seems to use a 64MB dictionary for the ultra preset, for both LZMA and LZMA2. You can select up to 1024MB, but of course you need something like 10-11GB for compressing. Nil Einne (talk) 05:22, 12 September 2012 (UTC)

That does sound right. My guess is something generated by a server is using p7zip, but I've no idea really (plus it's configurable, so could be anything, heh). :) ¦ Reisio (talk) 05:57, 12 September 2012 (UTC)

BTW I had a look at the en wiki dump [2] and it seems the dump isn't even in one file anyway. They are different size so I presume not multipart 7z but rather just compressed seperately Nil Einne (talk) 05:54, 13 September 2012 (UTC)

How to activate the text to-speech voice: "Hazel" in Microsoft Narrator?

Hello! :-)
(Windows7 Ultimate 64bit). I believe that I have (a legitimate copy of) the text-to-speech voice named: "Hazel" in a folder named: "TTS_MS_en-GB_Hazel_10.0" which contains the following 5 files:

Hazel.APM 4429KB

Hazel.INI 1KB
HazelT.UDT 2KB
License.rtf 130KB

MSTTSLocenGB.dat 5504KB

Into which folder do I have to put these files? to make "Hazel" replace or become an alternative to the default voice named:
"Microsoft Anna - English (United States)" ?
Which is shown at:
Control Panel --> Ease of Access --> Speech Recognition --> Text to Speech.
I would like "Hazel" to be the standard voice when I start Microsoft Narrator(v.6.1):
Start --> All Programs --> Accessories --> Ease of Access --> Narrator
Or at least to be listed as an option inside Narrator
( --> Preferences --> Voice Settings --> Select Voice )
--89.9.196.12 (talk) 02:51, 11 September 2012 (UTC)

Someone texting and calling using my number?

I have a Droid Incredible smartphone with Verizon. A friend of mine (on my contact list) received several calls from my number (he reported that the caller was breathing heavily into the phone but did not say anything) and then received a inflammatory text message from my number (I am also on his contact list). However, I did not send these texts and had my phone on me the whole time, so it was impossible for anyone to gain physical access to my phone.

Is is possible that someone is possibly "hacking" my phone and using my phone number to dial/text others? If so, is there anyway I can prevent this?

Thanks Acceptable (talk) 06:35, 11 September 2012 (UTC)

More likely spoofing the apparent number, which is not as easy as spoofing the "From:" in mail but not impossible. —Tamfang (talk) 07:15, 11 September 2012 (UTC)

See Caller ID spoofing. I agree with Tamfang that this likely didn't involve your phone. Instead, they fished your info off your friend's phone. StuRat (talk) 07:17, 11 September 2012 (UTC)

Verizon allows you to block spammy callers. If you're receiving harassing calls, you can contact Verizon, who may be able to help. That may be in order here anyway, since the number is apparently being spoofed. Nimur (talk) 16:45, 11 September 2012 (UTC)

If I call Verizon, would they be able to tell me the true phone number of the person who called me? Even if that person is using some third-party app or website to spoof their caller ID? Acceptable (talk) 01:58, 13 September 2012 (UTC)

Linux commands: Unzipping selectively bunch of files in linux, deleting all but two types of file

If you have a series of zip files, all containing pdf files and other stuff, how do you unzip all pdfs from all files into a directory?

How do you delete, for example, all files that are not *.txt or *.jpg files? Is there a rm 'whether txt not jpg' way of doing it? OsmanRF34 (talk) 13:48, 11 September 2012 (UTC)

If the zip file has nested directories, use "find". Otherwise just "mkdir savedir; mv *.txt *.jpg savedir" and delete anything left over. 67.119.15.30 (talk) 16:22, 11 September 2012 (UTC)

That is: for i in *zip; do unzip "$i" -d foo; done && find foo/ -iname '*.pdf' -exec mv {} foo/ \; && find foo/ -not -iname '*.pdf' -delete (just be careful about how & where you run the one with -delete :p) ¦ Reisio (talk) 01:53, 12 September 2012 (UTC)

(ec) There's probably a fancy way of doing this on a single line, but I think it is logically easier to move the files you want to keep to another directory, delete the rest, then move the kept files back again. You can do the same with a bunch of files you extracted from a series of zip files. Astronaut (talk) 16:26, 11 September 2012 (UTC)

Agreed. If you wanted to do it without moving files, you'd make a list of all files, pipe it to a command that removes the files you want to keep, then apply that shortened list to the delete command. StuRat (talk) 16:31, 11 September 2012 (UTC)

A quick-and-dirty Python script:

#!/usr/bin/python
import zipfile, os.path
def unzip_some_files(filename, extlist, destination='.'):
    zf = zipfile.ZipFile(filename)
    for n in zf.infolist():
        if os.path.splitext(n.filename.lower())[1][1:] in extlist:
            zf.extract(n,destination)

unzip_some_files('foo.zip',['txt','jpg'], destination='dest')

-- Finlay McWalterჷTalk 19:53, 11 September 2012 (UTC)

A quick-and-ugly command:

mkdir tmpzip unzipped && for var in ls *.zip; do unzip $var -d tmpzip; done && mv tmpzip/*.jpg unzipped && mv tmpzip/*.txt unzipped && rm -r tmpzip

At the end you'll have all your .jpg and .txt files in the unzipped directory. ListCheck (talk) 21:16, 11 September 2012 (UTC)

Power Control Center ?

I have one of these: [3], and would like to buy more, but with additional features.

Description:

It plugs into an outlet, and has 5 outlets on it, just like a power strip, and also has a surge protection feature. However, unlike a surge protector, each outgoing outlet is controlled by an individual on/off switch on the device, in addition to a switch to turn them all off at once.

Additional features desired:

1) Additional outlets. The more the better.

2) Instead of just on/off switches, I'd also like dimmer switches which vary the voltage (and not the old type that burns out quickly or gets hot/wastes energy).

3) Battery backup. Ideally, I'd like some outlets to have the battery backup feature, such as those running electronics, but not others, like those running a space heater, air conditioner, or refrigerator.

Anyone know of any devices like this ?

I don't think you'll find one device that has all these features in one, and if you do it might be overly gimmicky. Dimmer switches are NOT a common feature on anything AC except a light switch, what would you need dimmer switches for? Maybe you'd be better off with a variable power supply? Battery backup is just another word for UPS, they aren't cheap for a half decent one and I probably wouldn't reccomend one with a lot of "frills". Personally it sounds like you'd be better off sourcing 2 or 3 different devices for the specific features you are after, rather then one frankenstein. Vespine (talk) 22:25, 11 September 2012 (UTC)

Uses for dimmer switches:

A) Halogen and incandescent lights (used in winter only).

B) Electric fans (summer only).

C) Electric space heaters (winter only).

These devices often come with their own power control systems, but, in the case of halogen lights, the dimmer switch often fails, and in the other two cases the switches have 3 positions, rather than continuously variable controls. I also don't want to have to walk across the room every time I want to change the settings. StuRat (talk) 22:34, 11 September 2012 (UTC)

As far as UPS/battery backup, I just want enough time to close down what I'm working on on the computer, not to run for hours or days on it. StuRat (talk) 22:36, 11 September 2012 (UTC)

I don't think it's typically a great idea to dim just anything off an AC circuit, so I'm not sure you'll find something like a power conditioner with a dimmer on a regular power socket, by default. Some devices can be dimmed safely and efficiently, like maybe the fan, but other things, like halogen bulbs (which are designed to run above a certain temperature which is only maintained at something like >85% power rating), don't take to dimming very well, significantly lowering their efficency and life.. My recomendation is separate line dimmers for anything you specifially want dimmed, and a little UPS for your PC and the power conditioner for everything else. If you want it all in one unit, some duct tape might do the job ;) Vespine (talk) 04:48, 12 September 2012 (UTC)

I've already got wires all over the place, I was hoping to reduce the trip hazard, rather than increase it. In this room I have a TV, DVD player, digital converter box, mini fridge, 2 fans, a stereo, an intercom, 3 floor lamps, computer, PC, monitor, printer, external hard drive, cup warmer, 2 sets of speakers (one for TV and one for PC), microwave oven, clock, answering machine, and window A/C unit. That's 23 items with enough cords for a double-dutch tournament, not counting the numerous extension cords and power strips. StuRat (talk) 05:05, 12 September 2012 (UTC)

Wow, lol, that IS a lot of stuff... I wasn't questioning your "need" for such a device :) I just highly doubt one actually exists with ALL those features, I'll happily be proven wrong if someone has seen one for sale. Of course, if you have any friends that are into electronics... Because such a device wouldn't be too hard to build for anyone with minimal experience with mains voltage electronics, the only part I'd even need to research would be the UPS part since I've never built one before, but even if you bought a little UPS unit as the starting point and then just added everything else you wanted into a custom enclosure, it would be a piece of cake. Vespine (talk) 05:50, 12 September 2012 (UTC)

Apparently I'm not the only person to want such a thing. I found a homemade power control center made by a Brit. Type "Bespoke Dimmer Control Box" into Google image search to find it. StuRat (talk) 07:16, 12 September 2012 (UTC)

UPDATE: I just ordered 3 of these dimmer switches: [4]. Hopefully I can wire these in with my existing power control box. Still no UPS, though. StuRat (talk) 08:16, 12 September 2012 (UTC)

A standard light dimmer is not suitable for a fan - the solid state electronics are designed for a constant resistive load, and an electric motor can cause all sorts of issues. Fan dimmers can dim a light and have the extra bits thrown in needed to make sure a fan motor will run fine. Here is some information on the options: [5]. 209.131.76.183 (talk) 11:58, 12 September 2012 (UTC)

Is the model I bought a light dimmer ? It is the slide type, and they do call it a dimmer, but don't give the disclaimer that it's just for resistive loads, not inductive loads, as another model did. Also, 2 of the reviews are from people saying they are using it for fans, and it's working well for them. StuRat (talk) 12:22, 12 September 2012 (UTC)

The manufacturer's description only mentioned lights, and not other applications. It also says "Use with incandescent and halogen bulbs only", but I don't think standard CFLs work right on any sort of dimmer, so I could see putting that warning on a fan dimmer too. I wouldn't have bought it to use with a fan based on just the description, but if people in the reviews are using it for fans, that is a good sign. 209.131.76.183 (talk) 15:09, 12 September 2012 (UTC)

OK, good, I'll try it out that way then. The other two I had in mind for a halogen floor lamp and space heater (both in winter only). StuRat (talk) 20:42, 12 September 2012 (UTC)

Space heaters often require power in the vicinity of 1000 watts; the dimmer StuRat linked to was only rated for 500 watts. Of course the right approach is to hire an electrician to install sufficient outlets so there is always an outlet near each device, and at the same time, install an electric heater with a thermostat to turn it on and off as needed to achieve the required temperature. Jc3s5h (talk) 14:02, 13 September 2012 (UTC)

Yea, but that's thousands of dollars, versus the $30 I spent on the 3 dimmer switches (and I used my credit card reward points for that, so it's "free"). The space heater has low, medium, and high settings, which I guess are 500, 1000, and 1500 watts. I never use it above low, since it gets hot enough to burn you on medium or high. Actually, I'd like even less than low, which is where the dimmer switch comes in. StuRat (talk) 04:56, 14 September 2012 (UTC)

September 12

Google is being rude to me

Most of the time, when I do a Google image search, and pick on an image, it takes me to a page where I can choose to see the picture alone, go to the web page for that image, etc. Here's an example: [6].

If I don't want to do anything else with it, I can always hit the back button.

But, occasionally, I go to an image preview and it seems to hijack my browser, taking me immediately to the web page, like this one: [7]

The worst part is, I can't just hit the back button, or it goes right back to the same web site. If I hit the back button many times really fast, sometimes I can go back, but maybe too far.

So, what's going on here and how do I stop this behavior ? Does it do this for everyone else, too ? I'm on windows XP SP3 using Firefox 15.0.1. StuRat (talk) 06:35, 12 September 2012 (UTC)

AFAIK it's just poor website design of that particular page, nothing to do with Google. Best way to go back is to right click the back button and select the page you want from the drop down list. Even better, go into your Google search settings and check the box that says "Open each selected result in a new browser window" then you can just close the window when your done.--Shantavira|^{feed me} 08:11, 12 September 2012 (UTC)

Those are both good hints, thanks. But is there any way to stop it from doing this in the first place ? StuRat (talk) 08:54, 12 September 2012 (UTC)

The way I have always understood it is that the page itself has code designed to "escape" from Google, implemented in Javascript. An extension like NoScript will stop it, but I'm not sure if you can configure its filters to apply to just the situation of previewed pages in Google image search. 209.131.76.183 (talk) 11:39, 12 September 2012 (UTC)

I don't know if this is relevant, but the name of the webpage gives something away: ...utm_campaign=framebuster. The framebuster bit suggests the code is called from the url itself, or something like that. I don't know if that helps, and maybe someone can enlighten me as well about what exactly a url can control. Btw, I tried pasting the whole site name, and got spam blocked, because the site is on Wikipedia's blacklist IBE (talk) 04:31, 14 September 2012 (UTC)

Yea, I found a way around that in my 2nd link. Wikipedia spam-blocks "squidoo", so change it to "octopusoo", which apparently is a mirror site. :-) StuRat (talk) 04:40, 14 September 2012 (UTC)

Code and explanation (and claim of being the original creator) . Ssscienccce (talk) 07:34, 14 September 2012 (UTC)

Device Names in a Computer with 48 HDDs

In a computer with 48 SAS HDDs, the device names for the first 26 HDDs would be /dev/sda to /dev/sdz. What would be the device names for the remaining 22 HDDs? Now I don't actually have a computer with four dozen HDDs, nor am I planning to buy or build such a computer (presuming such a computer even exists), but I'm very curious to know. (Presuming that all the 48 HDDs are directly connected via HBAs, and there is no hardware RAID.) 08:04, 12 September 2012 (UTC)

Can you actually connect 48 hard drives ? I doubt that any normal PC has the ports, power supply, etc., to support anywhere near that many. I suspect you'd need to go to network attached storage at some point. StuRat (talk) 08:10, 12 September 2012 (UTC)

I know Dell sells rackmount computers with 24 HDDs, and Supermicro has a chassis for 36 HDDs, but I've never actually come across a computer with 48 HDDs, but my question still stands. Although I think 36 HDDs is probably the upper limit for a single computer, as no PSU could provide enough power for more than 36 HDDs - the chassis I've linked above has two PSUs because one probably isn't enough to provide enough power for 36 HDDs. 27.104.34.139 (talk) 08:40, 12 September 2012 (UTC)

Beyond the standard few, device nodes are created by whatever thing is managing the large scale storage. The names typically follow the pattern: sda, sdb, sdc, ..., sdz, sdaa, sdab, sdac etc. ref. What the kernel cares about is device nodes, and the storage manager would have to create nodes in a fashion (with mknod/makedev) that the kernel and its block device drivers will recognise. For basic SDx, the major number is 8, and you have 256 entries for minor, but as that document shows, it reserves 16 minors for each physical SDx (for its partitions, SDx1, SDx2, etc.) and so has to use multiple majors to handle >16 physical disks. It's up to whatever enterprise-y storage manager and its drivers (for e.g. the FC fabric HBAs) to agree between themselves what majors and minors they'd use. -- Finlay McWalterჷTalk 09:56, 12 September 2012 (UTC)

By the kernel's standard counting, the system can just keep adding letters forever - the relevant piece of code is here. But I think we still have 8 bits each for major and minor, so you won't get very far with actual dev nodes. -- Finlay McWalterჷTalk 10:51, 12 September 2012 (UTC)

Improving WINE compatibility

If a program does not run well under WINE, what can you do to improve it's compatibility? I'd like to run PDF-XChange Viewer, which is said to work well for some people, but I crashed with some specific pdf files or some commands (like find). OsmanRF34 (talk) 13:16, 12 September 2012 (UTC)

Determine which DLL seems to be the source of the crash. If you have access to do it legally, you can replace the WINE project's version of the DLL with one from an actual Windows system. If you know enough about software development, you could figure out which specific API call is causing the problem and try to debug the WINE source for it, improving the project for everyone. Comments on the winehq entry for PDF-XChange Viewer seem to imply that you may have luck running the portable version of it. 209.131.76.183 (talk) 15:02, 12 September 2012 (UTC)

You should consider the possibility that it might crash on those files in Windows as well. I'm not asserting that it does, but if it does, trying to fix the problem in WINE would be a waste of time. Looie496 (talk) 18:12, 12 September 2012 (UTC)

Look at the appdb.winehq.org page on the application, note the application (viewer) and Wine versions. For more problematic applications (that are also somewhat popular), there are also often detailed instructions for making things work. ¦ Reisio (talk) 01:01, 13 September 2012 (UTC)

Struggling to display images (showing broken links)

Hi all,

I'm having a bit of trouble with my private wiki (personal server) at the moment. im currently trying to get some images to display on one of my articles. i have edited the local settings.php which means i can successfully upload images, but when i try and display them using the [[file:blah.jpg]] code the image doesn't display, it just shows up with a broken link icon ><

it seems to me its a problem with authorization but i cant seem to find where, is it a server problem? or do i have to authorize the use of images somewhere? any help with this would be fantastic as im really stuck.

Nix

Nixxy00 (talk) 14:21, 12 September 2012 (UTC)

A good first step would be to confirm that the URL for the broken image file seems to match up with where your images are uploaded. That should help narrow down possible causes of the problem. If you try to open the image file directly via that URL you may also be able to get an HTTP error code. Right now I think the most likely problem is that there is a path configured wrong somewhere, so the links don't point to the same place the images are uploaded to. There could also be a file system level permissions issue, but I doubt it since the server should have uploaded them with permissions that allow it to read the file later. 209.131.76.183 (talk) 14:58, 12 September 2012 (UTC)

Thanks for the advice, i just tried that, when putting complete file path into the URL e.g. blah.com/wiki/images/9/imageiwant.jpg i get a server 403 error, saying i don't have permission :S BUT if i ftp an image into the file above e.g. /images i can access that though the a URL and it display fine, its weird because wiki uploaded the images (with correct height/width and image size) and put them in folder images/9 or images/9e etc but now cant seem to pull them out :S — Preceding unsigned comment added by Nixxy00 (talk • contribs) 16:06, 12 September 2012 (UTC)

That makes it sound like the file permissions are being set wrong by the uploader. You should see what your FTP client says the permissions are on the file. I suspect that there is no read access. 209.131.76.183 (talk) 19:34, 12 September 2012 (UTC)

ok i have checked the ftp and all the images folder and all sub folder incl image have read access for owner/group/public, i have unchecked and re checked but still no luck, is there something i have to do like authorize the image or something? it just seems weird that wiki can pull all the details about the image (filesize etc) but wont display the image itself

• on a side note every time i try and upload a new image it puts it in a sub folder of a sub folder (images/9/9e/image . png) is there a way i can set all uploads to a specific folder? this may not solve my original problem but it will make it easier to check file permissions etc. — Preceding unsigned comment added by Nixxy00 (talk • contribs) 09:34, 13 September 2012 (UTC)

I just realized I missed something before - it looks like you can ftp files to /image, and the wiki uploads them to a subdirectory, where they break. I think the file system permissions are fine - the PHP code for the wiki can open and inspect the files to get the information you mentioned. You probably have an .htaccess file or some other webserver-side access control preventing files from being hosted from subdirectories of the image directory. I bet if you dropped a file in a subdirectory via ftp it would give you the same error. 209.131.76.183 (talk) 14:36, 13 September 2012 (UTC)

yea it seems to error whatever i do, but i did a test, if i change the permissions on the folder (incl all containing folder) so that they can read/write AND execute on the owner, group and public level i can access the image on wiki, this is even more strange considering you cant execute an image so i have no idea why this should make a difference, but maybe i'll have a look into server settings see if its something on that side affecting it like u say (htaccess file or something) thanks again for your help :D Nixxy00 (talk) 08:04, 14 September 2012 (UTC)

That actually makes sense - here is the relevant article explaining what execute permission does for a directory: Filesystem permissions#permissions. I'm not sure why your wiki software created the directory with the wrong permissions, but it sounds like you're on the road to getting things going. 209.131.76.183 (talk) 12:31, 14 September 2012 (UTC)

September 13

OpenDNS disable?

How do i disable OpenDNS on my PC? When i go to certain websites it pops up and the site is blocked so i need to know how to get around it. Can anyone give me details on how to get rid of this Program? — Preceding unsigned comment added by 76.16.47.115 (talk) 00:59, 13 September 2012 (UTC)

OpenDNS is not a program, it's a name server. If this is your own internet connection, you can call your ISP and ask them to walk you through resetting your name servers. It's a common question and they'll know how to do it.

Note that OpenDNS probably isn't blocking anything (the web sites where you get the popup probably just don't exist), although according to the article they do offer a "FamilyShield" service that blocks some sites. -- BenRG (talk) 02:56, 13 September 2012 (UTC)

Also, note that OpenDNS does claim to block malicious sites. So if you are getting actual pop-up windows with the block message, then OpenDNS may actually be blocking malicious pop-ups for you. --Bavi H (talk) 03:51, 13 September 2012 (UTC)

Here are instructions for setting up OpenDNS: use.opendns.com. To remove OpenDNS, you would use the same instructions, but typically change the DNS settings to "obtain DNS server address automatically" or similar. There are DNS settings in your computer and your router, so check both places. Also see How do I Disable OpenDNS Completely?.

More information: As BenRG said, OpenDNS isn't a program, it's an alternative DNS server. A DNS server is like a directory assistance operator: Any time you go to a name address (like en.wikipedia.org), you computer asks the DNS server it has on file what the correct number address is for that name. You computer then connects to the number address to access the site. Usually your computer and router get DNS server settings automatically from your ISP. But you can override the automatic settings with any DNS server you want. --Bavi H (talk) 03:51, 13 September 2012 (UTC)

Can I do this in Microsoft Word?

I know it's often said that most people don't use 95% of the features in Microsoft Word. I'm one of those people so I assume what I'm thinking of is actually a feature unknown to me.

Is it possible in Word to fill in the blank or insert a word in 100 different places in an instant? I mean I have a long document I often use and need to change the name of the person in the document in 100 different places. Is it possible to set the document up in a way that allows me to change the name in all places by just doing so in one place?

Thanks in advance

Globalistcontributor (talk) 05:00, 13 September 2012 (UTC)

Have you looked at ms word mail merge? [8] This may possibly be what you are after, though you haven't really explained what you are trying to do. AndyTheGrump (talk) 05:06, 13 September 2012 (UTC)

There is the global search and replace ability (Control R). However, it might have problems changing "Smith" to "Jones" if there is also a "Smithers" (which would become "Jonesers"), or if "Smith" is misspelled somewhere. If there is an "entire word" selection box, that should avoid the first problem, but not the second.

Something else you might want to do is set up a template, with some unique character string like *LAST_NAME* wherever a last name belongs. Then you can do a global search and replace on that name whenever you need to put in an actual name, and save the document under a new name to preserve the template for next time. (From experience, it's best to make a backup copy or two of the template, too.) StuRat (talk) 05:10, 13 September 2012 (UTC)

You should always check the document after a global search and replace, though, as it can cause problems (in addition to those listed above):

A) There can be grammar problems, like if you replace "We purchased a computer" with "We purchased a X-ray machine" (here it should be "an X-ray machine").

B) There can also be spacing problems, if a longer word forces an illustration to jump to the next page, etc.

StuRat (talk) 05:23, 13 September 2012 (UTC)

Mail Merge and Fields in general seem to be the built-in features you're looking for, rather than StuRat's ad hoc methods. --Mr.98 (talk) 13:23, 13 September 2012 (UTC)

Do they avoid the problems I listed above ? StuRat (talk) 04:51, 14 September 2012 (UTC)

I'm on Linux, so no MS Word to test it, but my impression is that Fields are limited to certain special functions, and Variables would be the preferred solution. See this, or this: Variables make it possible to: Change text once and automatically update it everywhere.. Ssscienccce (talk) 07:55, 14 September 2012 (UTC)

Problem with attachments

Hello, everyone. Since yesterday, every single time I try to send an e-mail attachment, the program I use crashes. I've tried it on Firefox, Thunderbird and Internet Explorer (yes, I actually tried IE) with the same negative result, which makes me think this is a Windows problem. I've scanned my computer for malware and viruses and found nothing. What could be causing the problem? Thanks! Leptictidium (mt) 09:10, 13 September 2012 (UTC)

Okay, it just solved itself "magically". I deleted an MS Word file and it started working again. The weird thing is that the file was perfectly malware clean and functional, the only special thing about it is that it had quite a long name... Leptictidium (mt) 09:14, 13 September 2012 (UTC)

Maybe you have a shell extension installed that can't handle the filename. That would explain it happening in all three browsers and magically going away when a specific file is removed. The most obvious shell extensions do things like add extra options to the right-click menu, but you may have a more subtle one that came along with some piece of software on the system. Unfortunately Shell Extension is pretty useless for simply explaining what one is and giving examples of them. 209.131.76.183 (talk) 11:55, 13 September 2012 (UTC)

Most versatile laptop backpack?

My SwissGear Airflow (if "Airflow" is the model name) gave out after about 2 1/2 - 3 1/2 years of service. The straps are still together even though they look like they're about to snap apart, and a hole has already formed in the laptop compartment. I was troubled that it rained last night because I need the backpack's protection for my laptop.

I need a sturdier replacement backpack that will hold a 17" laptop, cushion it from falling shock, protect it from weather, and do an overall better job than SwissGear's pack did.

So do you know of laptop backpacks that will do it one better than the SwissGears? How much better, and how much would they cost? Please post more than one option as you know of them. Thanks. --70.179.167.78 (talk) 10:05, 13 September 2012 (UTC)

I've made excellent experience with using Tom Bihn's BrainCell inside normal, decent quality day packs (and bicycle paniers). Tom Bihn also offer backpacks specifically designed to clip in the laptop case, although I have never used them. Prices range from US$60 to a lot more, depending on what you need. However, I like the BrainCell so much that I even had it shipped to Europe the last time I needed one. I currently have two, one 10 years old and in perfect shape, the other ~5 years old and like new. --Stephan Schulz (talk) 14:34, 13 September 2012 (UTC)

Do you two know each other? Your Username 21:14, 13 September 2012 (UTC) — Preceding unsigned comment added by Hayttom (talk • contribs)

Note that you don't necessarily need a backpack designed specifically for a laptop. A general purpose backpack may well be cheaper, and one designed for campers may be sturdier. You may also want to add you own padding, such as bubble wrap. StuRat (talk) 04:47, 14 September 2012 (UTC)

Head First Java

What do people think of this as a book for learning Java? I am not a novice programmer and have done some work with Java before but want to develop my skills properly. Thanks. 188.223.81.244 (talk) 15:57, 13 September 2012 (UTC)

Here are some reviews of the book. - Cucumber Mike (talk) 16:16, 13 September 2012 (UTC)

Thanks but I guess I should have been a little more 'to the point'. While I realise that I can easily check reviews on the internet, these will quite often be posted by people who aren't in a position to judge whether or not the book is any good. In contrast to this, on the Wikipedia Computing refdesk, there are plenty of people who know what they're talking about and can offer an informed opinion on the subject. That's why I brought the question here. Has anyone ever read it? Thanks. 212.139.212.71 (talk) 19:02, 13 September 2012 (UTC)

I understand. However, we're currently having a little discussion about providing our own personal opinions in response to questions. Whilst your question is typical of many of the questions we've answered in the past, if it can't be answered by providing you with a reference it's not strictly a question we can or should answer. (In fact, as it says at the top of this page, "The reference desk does not answer requests for opinions".) I would argue that a) a review written in a respected magazine by someone who has read the book is more likely to be useful than some random nutcase like me who happens to have rocked up at Wikipedia claiming to know about computers, and b) if we told you the book was great, but when you bought it you found it wasn't suitable for you in some way we hadn't thought of, you'd be cross with us for wasting your money. Hence we offload the potential blame onto Google...

If you want to discuss this policy, please join the conversation on the talk page. We're still ironing out the best way to go about things, so your comments would be valuable. - Cucumber Mike (talk) 20:19, 13 September 2012 (UTC)

Star Control II on Linux via emulator?

If I can't get The Ur-Quan Masters working on my Fedora 17 Linux system, would it be a good idea to actually buy the original Star Control II from eBay and try to get it working via an MS-DOS emulator? I do have both a CD-ROM drive and an HD floppy drive in my computer. Is there a working MS-DOS emulator for Linux? Do I need some copyrighted ROM images, like I needed the Amiga KickStart ROM images for E-UAE, which I was able to provide because I have legally bought the Amiga Forever CD-ROM? JIP | Talk 17:26, 13 September 2012 (UTC)

DOSBox would seem to be the working MS-DOS emulator you're looking for. There's even a Fedora specific download. I'm not familiar with either of the games you mention, so I'll have to leave someone else to help you with the specific files you need, but I'll note that Star Control I and II are available together for $5.99 on GOG.com (a site which normally ensures that the games they sell are compatible with DOSBox). - Cucumber Mike (talk) 17:37, 13 September 2012 (UTC)

(EC) DOSBox which in various forms is likely the first several results for simple search for 'dos emulator' is the DOS emulator everyone uses for DOS games. I haven't personally tried Star Control II, but it's a popular enough game that there should be compatibility reports. As our article mentions, DOSbox is in the software respository for a number of Linux distros and has been ported to many different OSes. As our article mentions, it emulates most essential hardware (including the x86 CPU) for running games so works on a wide variety of hardware. Of course since it emulates, it's possible the game may be a little slow if it was one of the last few games released for DOS and was fairly demanding, on some of the more obscure hardware; but this is unlikely to be a problem on any modern desktop or laptop computer, and is unlikely to be a problem for Star Control II in any case. As our article mentions, the only copyrighted ROMs that are likely relevant would be those of some of the sound hardware it can emulate, in particular the MT32. P.S. [9] is a decent site for help with running generic old games. Nil Einne (talk) 17:55, 13 September 2012 (UTC)

The reason DosBox doesn't need a binary dump from a real BIOS ROM is that DosBox emulates the binary interface a PC BIOS presents to subsequent programs. That is, it implements the same interrupt handlers (the IBM PC's primitive API/ABI, essentially) which are hooked by a real BIOS. So it emulates a BIOS (and VBE, I think) but doesn't run one. This is different from virtualisation solutions like VmWare and VirtualBox, which actually run real BIOS images (and I assume adapter ROM images for their fake video devices too). I don't know whence VirtualBox' one comes, buy VmWare's seems to be an actual licenced Phoenix BIOS. -- Finlay McWalterჷTalk 20:10, 13 September 2012 (UTC)

34-Pin FDD to 40-Pin IDE

I recently bought a 3.5" Floppy Disk Drive and installed it in my PC's chassis, but when I proceeded to connect the cable, I found that the FDD side has a 34-Pin port and my motherboard has only 40-Pin IDE ports, is this possible to connect the FDD to the motherboard, do i need some kind of adapter and where to get one, thank you for any help you can provide. 27.104.166.178 (talk) —Preceding undated comment added 19:30, 13 September 2012 (UTC)

The two standards are completely incompatible (despite their connectors looking similar) - compare the pinout described in the Parallel ATA with the floppy pinout. As you've discovered, few recent motherboards have FDD connections any more, and while some people (supposedly) sell PCI adapter cards with floppy drive controller interfaces and the appropriate header, I don't know if I'd be confident that you'd get those working. I recently found myself in a similar situation like you, with a couple of old but probably functional internal 3.5" floppy drives sitting around, and no machine that would take them. When I had to read and convert a bunch of ancient floppies a family member found in a box somewhere, I bought a new USB floppy drive and used that. It worked as flawlessly and as painlessly as you can imagine reading 200 glacially slow disks could ever reasonably get. Even though you've just bought that drive, the USB way is still probably the path of least suffering for you. In the worst case, you might be able to find an older PC that someone is discarding, and using it (assuming it does still have a FDD riser) to read that box of floppies I imagine you've just been handed. -- Finlay McWalterჷTalk 19:54, 13 September 2012 (UTC)

27.104: The similar-looking ports are utterly incompatible, even the voltage levels are way off. Trying to convert between them using pure copper (as opposed to an interface with a chip on it) will only fry the drive and probably your mobo.

If you want a cheap solution, try to get your hands on an old PC (late 90s/early 2000s should be decent), install an OS (Windows 98 or XP - chances are you'll have a genuine license for one of these which is not in use), and hook it up to your LAN. (Many mobos have a LAN connector on-board - otherwise chances are you can get used LAN interface cards for free, too)

Install the floppy drive there, and share it to the LAN - read access should be fine for retrieval.

If you don't feel like screwing around with hardware and OSes, get the USB solution, but you won't get the chance to boot from there (FWIW). And (grapevine - could anyone else add on this?) most USB FFDs suck at error correction too. If you have a lot of faulty floppies, having to wait for 30 seconds until the drive gives up is a pain.

Finlay: Don't underestimate the value of old floppies.

3.5" floppies are quite easily fucked up (usually they develop waves and bumps near the sheet-metal part), but I have some good 5.25s from the late 80s. When I did a scan of these last year, ALL of these (~80) were fully readable. So, cause I don't trust USB flash media in their fullest, I save small files which don't need multi-megabyte volumes anyway (batches, boot.ini, WP articles, etc) to floppies. Works like a charm, and inserting a floppy is not that much slower than inserting a flash drive anyway. - ¡Ouch! (^{hurt me} / _{more pain}) 08:55, 14 September 2012 (UTC)

September 14

How do you use Dia?

Just kidding. This is of course not the kind of question that should be posted here -- though it's not so different from many that are posted, and then even get polite and helpful answers.

Well, half kidding. I've just encountered "Wikipedia:How to draw a diagram with Dia" for the first time. This started off as a (terrible) article in mainspace, as far back as 2003. I have just now fiddled with it so that in various, mostly trivial ways it's perhaps rather less obviously terrible than it was an hour ago. (Sample: "I like Dia".) But it's still terrible. I neither have used Dia nor have any pressing need to do so, but if you, reading this, do know Dia and are in a pedagogic/altruistic mood, then Wikipedia:How to draw a diagram with Dia might be worth some of your time. -- Hoary (talk) 08:43, 14 September 2012 (UTC)

The page probably doesn't belong in WP space either. It should be moved to wikibooks or wikiversity. Taemyr (talk) 13:44, 14 September 2012 (UTC)

please how can i compile a kernel which can be used in the cdrom:/isolinux

Question moved from the misc reference desk. --ColinFine (talk) 11:13, 14 September 2012 (UTC)

if i have nothing,but i want to generate a cdrom with linux system,such as fedora 16. then i get the kernel source from "kernel.org".now,i need to compile a kernel for isolinux/,and i saw it's name usually called "vmlinuz",and i need initrd.img too,actually more,such as isolinux.cfg,isolinux.bin and so on. but the "vmlinuz" is different from i compiled before which be put on /boot in the exist system. i really want to know how can i compile it.please help me.thanks very much. — Preceding unsigned comment added by Huluobo007 (talk • contribs) 08:31, 14 September 2012 (UTC)

Google Reader not working with Google Alerts feeds

Hi,

Today, for the first time, Google reader tells me that I am not allowed to display feeds from Google alerts. However, feeds from other providers are displayed as usual in Google Reader. Moreover, if I copy the feed URL from Google Reader and paste it into my browser's address bar, the feed content is displayed normally. Any ideas?

Thanks. Apokrif (talk) 12:56, 14 September 2012 (UTC)