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August 26

A little help please with new windows install/getting my hardware to work?

I have a Gateway LX6810-01 http://support.gateway.com/s/PC/LX/LX6810/LX6810sp3.shtml

i just installed windows 7 and started installing drivers from here: http://support.gateway.com/us/en/product/default.aspx?tab=1

...but its so confusing.... which ones do i get? So far ive installed....

The top (NVIDIA) audio driver... The bottom chipset driver... and i think the middle VGA driver

on that page.... Do i need any of the others, like the chipset driver that says its for "MCP7A" ?

Also, i have a 15 in one card reader that used to show up in "My computer" as 4 or 5 different devices, how do i get those to show again? Additionally i have a tv tuner and an infrared remote im wondering about as well.

I know its alot of items, but if anyone has knowledge on any of these hardware devices id very much appreciate it. Thanks!

216.173.144.164 (talk) 01:27, 26 August 2011 (UTC)

Did you try installing the detection utility from support page? Kushal (talk) 19:30, 31 August 2011 (UTC)

Missing audio channel?

Hello. I am listening to Pandora Radio and it seems that I am getting only one channel of stereo audio from the site. Sound is coming from both of my speakers, and my audio control is set to the middle, yet I only hear one channel of the music. There is also a bit of "echo" coming from Pandora (but not from any other site). Is there a setting somewhere that I've missed? — Michael J 04:49, 26 August 2011 (UTC)

extracting 3d coordiantes from 2d images of face

Is there a way that one can merge two or three 2d images of the same object (from different angles) to create its 3d model? Suppose i have a few samples of a face from a face database then i want to make its 3d model, the objective is to get the 3d coordinates of different points on the face. Can this be done or is there any alternative way to get the 3d coordinates?--tathagata 17:26, 26 August 2011 (UTC) — Preceding unsigned comment added by Nonstop funstop (talk • contribs)

Yes, it can be done, and fairly easily with a frontal shot and a profile. Of course, this will only give you half the face, since one profile only shows half the face. You could then either mirror that half of the face to get the other side (which would only be an approximation, since faces aren't completely symmetrical), or use another profile shot to get the other side. The 3D reconstruction could also be done using different angles, but would be more complex and the results less accurate. In any case, the trickiest bit is mapping each point from one pic to the other, say the tip of the nose, corners of the mouth and eyes, etc. StuRat (talk) 17:32, 26 August 2011 (UTC)

As far as alternative methods, I suppose you could take a single frontal shot, and project it onto a "standard face". You'd need to pick a standard face from a library based on the face outline, eye position and size, mouth position and size, etc. The height of the nose, etc., might not be quite right, though. Note that facial hair would be most difficult to map using this method, but would also be a problem with any method. StuRat (talk) 17:40, 26 August 2011 (UTC)

Some research paper links: Generation of a 3-D Face Model from One Camera; Stereo photogrammetry for generating and matching facial models. We also have an article on photogrammetry. You might also want to look at geometric modeling. There are numerous ways to represent faces: feature-models; point clouds; polygon meshes; eigenface or generalized geometric basis coefficients; and so on. What are you looking for? Nimur (talk) 18:12, 26 August 2011 (UTC)

i think the problem is solved. i have exported .stl files using geomagic studios (from the wrl files in the database) and this is easily accessible through matlab. thanks anyway for your suggestions...--tathagata 18:27, 27 August 2011 (UTC) — Preceding unsigned comment added by Nonstop funstop (talk • contribs)

August 27

Reading PDFs that have columns

(I searched the Archives for this topic and got 100s of hits. I hope someone can point me to an answer.)

Reading a two column PDF document with Foxit Reader is very fiddly. Scroll down left col, move up to top of page, move to right side of page, scroll down right col, jump to next page, jump to left side, continue over & over & over. (I can view two column widths but the font size is too small for comfortable reading.)

The mechanics of moving the view area are a major distraction from the actual reading. I have done this many times but it struck me today that there must be a program for reading PDFs that would not require moving between left and right columns.

Is there such a program? Or is there a better way of using the program I am using?

Thanks, Wanderer57 (talk) 00:25, 27 August 2011 (UTC)

Preview, on the Mac, with a Magic Trackpad, is very convenient. Just slide your hands around, and the PDF display similarly slides around.

On iPad, you can double-tap to zoom in to content areas. When you are done reading, just unzoom to see the full document.

If you're committed to reformatting your document, PDF is not really the best file format; reflowable documents like a Microsoft Word document or an HTML file allow the layout-engine to dynamically reflow text. PDFs are intended to deny you this capability, because they are supposed to mimic paper-printouts. Nimur (talk) 03:33, 27 August 2011 (UTC)

Thank you. Just to clarify, PDF is not my "choice" but it is okay for reading single column PDF documents.

I just tried something which seemed to come close to doing what I would like to have happen. I selected a block of text (which can be the whole document),and pasted it into Microsoft Word. The text appears in single column format (good) but each line in the initial text is treated as a separate paragraph (bad) and all spaces between words are lost (very bad).

I wonder about the value of a copy/paste function that loses the separation between words. Maybe from the POV of the developer this is a feature rather than a flaw? Wanderer57 (talk) 12:54, 27 August 2011 (UTC)

It has to do with how PDFs store text. They don't store it as coherent text flows the way that word processors do; they see them more as masses of characters. It's part of the prioritization of making sure everything looks identical on every computer system. It's one of the down sides of using PDFs in this way. --Mr.98 (talk) 13:16, 27 August 2011 (UTC)

In Adobe Reader, you can use View → Zoom → Reflow to reformat multiple columns into one column. It works with plain column layouts, but has more difficulty with complex layouts. Perhaps Foxit Reader also has a Reflow command? --Bavi H (talk) 14:35, 27 August 2011 (UTC)

Thanks. I tried the Adobe Reader Reflow. It works. However when the font size is enlarged, the letters crowd together, giving the same result as in Word. Wanderer57 (talk) 18:46, 27 August 2011 (UTC)

There's also the hand tool, which allows you grab the page and pull it around, and is a lot more convenient than clicking scroll buttons. (Too obvious?) ... and the page up button on the keyboard, for getting back to the top of the page when you reach the foot of a column.  Card Zero  (talk) 13:35, 28 August 2011 (UTC)

Secret Facebook Group

I have created a secret Facebook group for communication between members of a teenage youth organisation of around 20 members. I would love to somehow publish the organisation's future program of events there. Anyone know how to do that? (I know how to add single events, but with a program of, say, 20 special activities over the next 12 months, that would get very clumsy.) So, any ideas please? HiLo48 (talk) 03:38, 27 August 2011 (UTC)

You could list them in a "Doc" (document) on the right side of the page. — Michael J 03:40, 27 August 2011 (UTC)

Yeah, that's worth a try. Thanks. HiLo48 (talk) 04:15, 27 August 2011 (UTC)

(Handy hint from experience using Docs: If you want to leave a blank line between paragraphs, you have to type "space-return". Just hitting return will close up the double-space upon saving.) — Michael J 04:54, 27 August 2011 (UTC)

Are hex codes, CMYK, and RGB equivalent, or does one have greater color range than the rest?

Googling for this gets me lots of tools to convert back and forth, but no answer to my question. It's simple really - do hex codes, CMYK, and RGB colors on the computer describe the same range of color, or is one of those notations more comprehensive than the rest? The Masked Booby (talk) 10:10, 27 August 2011 (UTC)

1. Hex codes are just a way to describe RGB values. RGB can also be specified in decimal notation. You have three channels -- red, green, and blue -- and each usually has eight bits. Eight bits is eight zeros or ones. So, the maximum decimal value of each channel is 255 (or FF in hexadecimal). CMYK is usually described using percentages. You have 0 to 100% of each color.
2. An eight-bit per channel CMYK image will have more colors to work with than an eight-bit per channel RGB image. Why? Because CMYK has four channels, and RGB has only three.

—Best Dog Ever (talk) 10:32, 27 August 2011 (UTC)

When I put hex codes into InkScape it always adds an additional 2 characters for ... saturation? Not sure. That's what prompted me to ask...The Masked Booby (talk) 10:44, 27 August 2011 (UTC)

My recollection is that those extra two codes are for opacity (alpha). --Mr.98 (talk) 13:11, 27 August 2011 (UTC)

Not saturation, alpha value (transparency). An alpha of 255 (xff) is the full colour of that object; of 0 it's the full colour of whatever is underneath it; intermediate values between the two blend together. -- Finlay McWalter ☻ Talk 13:12, 27 August 2011 (UTC)

It's complicated. There are many different color standards called "RGB" and "CMYK". sRGB is the standard RGB color space of the web, modern video cards, and modern monitors. The six-digit hex codes like #89abcd identify sRGB colors; the colors you can represent with those hex codes are the same as the colors your video card can display in "24-bit color" (or "32-bit color") mode. I don't know much about CMYK (subtractive color), but I'm pretty sure most/all CMYK spaces can represent colors outside the sRGB gamut. However, your monitor can't reproduce those colors. You shouldn't necessarily trust any online conversion tools you might have found. I googled "rgb to cmyk" and the first two hits were [1][2]. These sites are worthless, made by people who have no idea what they're doing, and do not actually convert between real RGB and CMYK spaces. -- BenRG (talk) 10:36, 27 August 2011 (UTC)

Gamuts and accurate reproducible colour systems matter very much if you're designing for a medium where the final product will be reproduced with a reliable colour-accurate scheme (like magazine printing or rendering to film stock). But if you're designing for the small (domestic) screen, for a medium like TV or the web, where displays are poorly calibrated and quite divergent in their colour response, there's only so much effort that's worth putting into worrying about accurate colour imaging. Whenever a designer complains to me that object A should be "just a little more green" I drag it over to the other screen of my dual-monitor system (both are decent enough screens, but of a normal office/consumer grade) where she sees the same green isn't the same green at all. -- Finlay McWalter ☻ Talk 13:18, 27 August 2011 (UTC)

Also note that most TVs or monitors can have their color settings changed by the user, at the hardware level and/or with software settings. StuRat (talk) 17:57, 27 August 2011 (UTC)

We have a gamut article that explains this better than any RefDesk answer possibly could, I believe. Looie496 (talk) 17:05, 27 August 2011 (UTC)

What irc channel has the most people in it?

What irc channel has the most people in it? — Preceding unsigned comment added by 173.53.127.9 (talk) 14:15, 27 August 2011 (UTC)

It's been a while since I've 'irced' but I remember that mirc had a channel list function and you could sort that list by the number of people in each channel. Most popular channels vary from server to server. Sandman30s (talk) 08:19, 28 August 2011 (UTC)

My pro-Wikipedia bias wants me to say #wikipedia-en ^connect --Σ _{^talkcontribs} 08:21, 28 August 2011 (UTC)

That only has 150, #python has over 800 people and I've seen other channels go over 1,000 a few times. 82.43.90.90 (talk) 21:22, 28 August 2011 (UTC)

Why is idling in irc channels considered bad?

Why is idling in irc channels considered bad? — Preceding unsigned comment added by 173.53.127.9 (talk) 14:15, 27 August 2011 (UTC)

Is it? I do it all the time, and so do many of my friends.

Must be a social thing among certain groups of people. Where do you learn this? APL (talk) 21:33, 27 August 2011 (UTC)

It's called lurking. And no, I also don't think it's considered bad, depends on what channel I guess. Sometimes having lurkers in a channel can make the more active members feel like having a silent audience which can make them uncomfortable, or it may be that you were supposed to contribute to the discussions but aren't doing so, it may also be frustrating for some to see a full channel and no one talking, etc. Some channels might kick you out, but in my experience, it's perfectly fine. -- Obsidi♠n Soul 21:47, 27 August 2011 (UTC)

How to sync a Palm Tungsten E with a Dell Studio XPS with windows 7 ?

Can a Palm Tungsten E sync with Windows 7? — Preceding unsigned comment added by 24.102.168.98 (talk) 14:47, 27 August 2011 (UTC)

Maybe. --Ouro (blah blah) 11:44, 28 August 2011 (UTC)

Free PDF software

I'm looking for a free online PDF creator and this site is the first hit I got back from Google. On trying to download my computer warned me that files of this type can be harmful. So I'm just wondering if anyone has used this site and if it's safe to download. Cheers TheRetroGuy (talk) 14:51, 27 August 2011 (UTC)

Any executable files you get from the internet can be harmful. That isn't a very strong statement other than saying, "do a little investigation first." Googling for "PDF Creator" (the software in question) turns up a SourceForge project which includes reviews that are a pretty good way to tell you whether it's something you want or not. The reviews are pretty mixed — it seems like it installs some sort of adware or spyware as well. --Mr.98 (talk) 18:36, 27 August 2011 (UTC)

Cheers. Perhaps not such a good idea for me to install it then. I was hoping to get away without having to spend several hundred pounds on Adobe's version, but maybe that's the best thing to do. At least I won't get any unwanted spyware with that. I'll keep looking though before I make a final decision, but having said that, I'd be interested to hear from anyone who has installed a free PDF maker. If there is a reliable one around it would save me a bit of cash. TheRetroGuy (talk) 19:34, 27 August 2011 (UTC)

It's safe to install PDF Creator if you download it from SourceForge. It does have bundled adware, which you can (and obviously should) opt out of during the install. I wouldn't install it (or any software) from random single-page third-party sites like the one you linked, because people have been known to create custom installers for legitimate products that silently install malware at the same time (without giving you a chance to opt out). Legitimate sites are the ones with update logs, previous versions available for download, an active discussion forum, etc. Another way to find the legitimate site is to follow the link from the Wikipedia article. -- BenRG (talk) 20:12, 27 August 2011 (UTC)

CutePDF is probably worth a look. We use it at work (it's free for commercial use as well) and you simply "Print" to a PDF printer and it just works perfectly for what we want.  ZX81  ^talk 19:48, 27 August 2011 (UTC)

Thanks, I'll take a look at that. TheRetroGuy (talk) 19:56, 27 August 2011 (UTC)

Another point just to throw out there is that if you switch to LaTeX for document creation, making PDFs of the output is automatic. I won't kid you though; the buy-in is pretty big. The payoff is also big but only after a high learning burden. --Trovatore (talk) 19:57, 27 August 2011 (UTC)

Cheers. I basically need one to submit a manuscript as they want it in PDF format. Why they can't accept Word is beyond me. TheRetroGuy (talk) 20:01, 27 August 2011 (UTC)

Probably because Word creates an evil, non-documented, proprietary format. And because Word files from different versions are not always compatible with other Word versions. That said, your simplest option is probably to install OpenOffice/LibreOffice, which is as compatible with MS Word as other versions, and which allows you to export to PDF directly. --Stephan Schulz (talk) 20:05, 27 August 2011 (UTC)

Actually newer versions of Word used Office Open XML, which is open, documented, and only mildly malcontent. --Mr.98 (talk) 20:25, 27 August 2011 (UTC)

I don't think that's irrational. Word docs can look different on different machines (for example, if you don't have the same fontset installed, and possibly even just because you're using a different release of Word, though I don't know how far apart they'd have to be before you'd notice that). PDF is more reliably portable — if I understand correctly, the fonts are embedded in the document itself (not sure if that's always true?) and the pagination and margins are completely determined. Another nice thing, though more for you than for them, is that PDF is harder to modify, so unless someone works hard to mess with it, if they show you your document back you can be reasonably confident it's the same way you sent it to them. --Trovatore (talk) 20:07, 27 August 2011 (UTC)

ok, now have OpenOffice downloaded so will mess about with it for a while. I see from the File menu I can export a document in PDF format so hopefully it should give me what I need. Think I might also grab CutePDF. Thanks for all the help and suggestions. Cheers TheRetroGuy (talk) 21:53, 27 August 2011 (UTC)

I'm late to the party but I've also used CutePDF Writer and OpenOffice to create PDF files. I have Office 2010 on one machine here, and although they are also late to the party, Microsoft now supports writing PDF files in Office 2010. Comet Tuttle (talk) 16:07, 28 August 2011 (UTC)

Actually they did in 2007 as well. But it was removed by the default install due to a legal threat from Adobe so you had to download the PDF export seperately. It was added back in one of the service packs I believe. Nil Einne (talk) 17:21, 28 August 2011 (UTC)

I recommend PrimoPDF from personal experience. Rocketshiporion♫ 22:05, 28 August 2011 (UTC)

Maximum RAM capacity for a Compaq presario CM2050 1456VQL1N laptop

I'm trying find out the maximum this computer's hardware allows. I'm tired of searching through forums and would appreciate some kind soul that would throw me a fish. Thanks. 69.243.220.115 (talk) 15:47, 27 August 2011 (UTC)

The best approach for questions like this is usually to connect the computer to www.crucial.com and run their online memory advisor -- it not only tells you the capacity, but what kind of memory will work for you. Other than that all I can say is good luck bwah hah hah hah. (You'll have trouble finding any that works for such an antiquated beast.) Looie496 (talk) 19:01, 27 August 2011 (UTC)

"Additional logon information required" error message Windows 7

I am using Windows 7 (Home Premium) on my laptop. When i connect it to the LAN with RJ 45 connector it shows the error message "Additional log on information may be required". When i open my browser it says "Update your browser" and does not open the site. This happens on all the browser and even though i have the latest versions of each. This problem goes away after waiting for a few minutes. Any ideas?Shraktu (talk) 15:49, 27 August 2011 (UTC)

To get a working internet connection, your computer has to connect (via your modem) to your Internet Service Provider, and be accepted as a valid client. That connection process is where the difficulty is occurring, but the solution to the problem may be specific to the internet provider you are using (which you haven't told us). Looie496 (talk) 18:47, 27 August 2011 (UTC)

It sounds like it might be trying to do a network login, where, instead of running things locally on your computer, it tries to load them over the network (then eventually gives up and does run them locally). So, if there's a way to turn that option off, I'd try that. StuRat (talk) 07:39, 28 August 2011 (UTC)

This sounds similar to some public WiFi networks that require you to log in before you can browse websites. If you connect to a network like this, any address you enter in your browser will take you to the log in page.

See Windows 7 Network Awareness. When you connect to a WiFi network (and I guess also when you plug in an Ethernet cable), Windows checks a specific Microsoft website as a test. If it doesn't get the expected response, it thinks you might be connected to a network that prompts you for a log in. That's why it shows the message "Additional log on information may be required."

In your case, it sounds like something is redirecting any website address you enter to a message asking you to update your browser. This redirection may be caused by your ISP or by your router. Or if you have manually configured DNS server addresses, it may be caused by your DNS provider. On the "Update your browser" page, look for any logos or company names. That might provide a clue who is doing the redirection. --Bavi H (talk) 18:06, 28 August 2011 (UTC)

I think you're referring to a captive portal. I had a ADSL router modem that had a captive portal that showed up when the modem was having problems logging on but also showed up when the modem had just been started and hadn't yet managed to log on, perhaps that's what the OP is referring to. Nil Einne (talk) 18:28, 28 August 2011 (UTC)

Resolved

Shraktu (talk) 04:42, 25 April 2012 (UTC)

Mozilla support forums - few messages since August 18

I read two Mozilla newsgroup support forums mozilla.support.thunderbird and mozilla.support.firefox. Up through August 18 there were several messages per day but only a trickle since then, and one of them was asking why there are no new messages. Has something changed about the Mozilla support newsgroups that would cause me to not get new messages? Bubba73 ^{You talkin' to me?} 21:06, 27 August 2011 (UTC)

Resolved

Bubba73 ^{You talkin' to me?} 02:12, 29 August 2011 (UTC)

select count vs. mysql_num_rows

I have been testing this and I want to ensure this isn't an anomaly on my box. I have a MySQL database table with about 2 million rows. I want to know how many records meet a certain criteria. I have two options. I can use a "select count(*)" query that returns the count -or- I can use a "select id from" query that selects all the ID's that match and use mysql_num_rows to count how many records the query matched. In my test, select count is much faster than mysql_num_rows. However, I've been told that they should be the same. Can anyone else verify if my results are correct or not? -- kainaw™ 23:55, 27 August 2011 (UTC)

I've not done any testing of this, but I would personally expect select count to ALWAYS be faster. That way the server simply calculates the total rows, end of story. The other way it has to actually gather up all the data and generate a recordset for the client only then to be told to get the row count instead of looking at the actual data. The speed difference is going to be down to the amount of data and the speed of the hardware, but I can't see select count ever being slower.  ZX81  ^talk 01:57, 28 August 2011 (UTC)

Agreed. StuRat (talk) 07:00, 28 August 2011 (UTC)

This page suggests that MySQL caches the row counts in tables, which is why count(*) is so fast. I don't know if that's true, but it would make sense if it was. --Mr.98 (talk) 02:09, 28 August 2011 (UTC)

Thanks. -- kainaw™ 11:57, 28 August 2011 (UTC)

August 28

New technology info

Can anyone suggest some good online resources for finding out about new technological advances, gadgetry, trends, etc etc? Dismas|^(talk) 01:19, 28 August 2011 (UTC)

I like the KurzweilAI daily/weekly newsletter. sample --Codell (talk) 01:57, 28 August 2011 (UTC)

Ars Technica is a pretty common tech news resource. --Mr.98 (talk) 02:11, 28 August 2011 (UTC)

TG Daily Sandman30s (talk) 08:16, 28 August 2011 (UTC)

Thanks! Dismas|^(talk) 06:04, 29 August 2011 (UTC)

Stellarium

In Stellarium, how do I keep an astronomical object (specifically the Moon) to be always on the screen? 123.24.89.84 (talk) 06:00, 28 August 2011 (UTC)

Select the object you want to track – using the search window (F3) if necessary – and press space. You will then keep tracking that object, as long as you don't select anything else. Of course, you may need to turn off the ground and atmosphere (keyboard shortcuts G and A, respectively) to see it at all times. --Link ^(t•c•m) 10:25, 28 August 2011 (UTC)

NLB Browsers in Windows 7

Hey, I've got two internet connections to my pc, windows 7 automatically load balances between them but unfortunately there is only an improvement with concurrent downloads e.g gaming at the same time as downloading files.

I have been searching for some way to load balance the traffic from just a single process (web browser/SVN client etc.) across both connections. would it be possible, and do you know how? I've done plenty of googling, but perhaps i'm searching for the wrong thing. I know bit torrent programs will work well, but i'm not interested in them.

Thanks in advance Benjamint 12:05, 28 August 2011 (UTC)

API usage to view deleted file

Resolved: Magog the Ogre (talk) 18:22, 28 August 2011 (UTC)

I'd like to be able to view a deleted image via the API. However, the API only allows me to view deleted edits [3]. Is there a way to view a deleted image file through the API, or would I have to put together a hack of the HTML? Magog the Ogre (talk) 18:05, 28 August 2011 (UTC)

PS. If it is possible, is it possible to create a thumbnailed version, like it is with all non-deleted images in the history of a file? Magog the Ogre (talk) 18:07, 28 August 2011 (UTC)

The Help desk or Village Pump might be better places to ask about Wikipedia specific questions. And it seems like only administrators will be able to answer this question fully, as viewing deleted edits requires an account with the administrator flag 82.43.90.90 (talk) 18:13, 28 August 2011 (UTC)

{{Trout}} on me. I meant to post this at the Village Pump. Thanks . Magog the Ogre (talk) 18:22, 28 August 2011 (UTC)

Chrome IDN whitelist

Dear Wikipedians:

Is there an extension or setting in Chrome that will allow me to add sites whose IDN I wish to display in Unicode instead of Punycode no matter what Chrome may think otherwise?

As an example, Chrome says that it will never display http://☃.net/ in Punycode, but I would like it to show up as the cute Unicode snowman. Is there anyone I can make Chrome do it?

Thanks,

科幻南北朝 (talk) 19:53, 28 August 2011 (UTC)

Internet explorer first to use domain greying out in address bar?

I just noticed in my Firefox, that the URL .com is in black and the rest is grey. Obviously good to know the root URL on complex URLs. I think IE did it first on IE7 or something. — Preceding unsigned comment added by 66.23.238.101 (talk) 20:42, 28 August 2011 (UTC)

IIRC Internet Explorer was the first popular browser to inflict this nonsense on users, yes. ¦ Reisio (talk) 16:54, 29 August 2011 (UTC)

I find this feature useful. To turn it off in Firefox, browse to about:config, search for browser.urlbar.formatting.enabled and set it to false. Certes (talk) 22:05, 29 August 2011 (UTC)

Symantec Norton Ghost 15.0 - Tape Drive Support

Good Morning, CompRefDesk!

  Does Symantec Norton Ghost 15.0 support backing up to a tape drive? And can backups to a tape drive be scheduled?

  Thanks as always to all respondants. Rocketshiporion♫ 21:56, 28 August 2011 (UTC)

This post suggests they do support tape drive backups and ghost was designed for automation...so it can probably be scheduled.Smallman12q (talk) 15:48, 31 August 2011 (UTC)

August 29

First stage bootloader larger than 512 bytes

I want to write a secure bootloader that will verify the digital signature of whatever it is goong to boot. I think it would need more than 512 bytes to fit all of the code, so I need to find a way that will make it possible to do this. Maybe a disk that does use sectors or is sectorless would work since the 512 byte limit is based on sector size? --Melab±1 ☎ 02:37, 29 August 2011 (UTC)

Advanced Format drives have 4096-byte sectors. A disk cannot be sectorless; as the sector is the basic unit in a data storage device in which data is stored. Rocketshiporion♫ 04:45, 29 August 2011 (UTC)

In the old days of floppy discs, it was possible to read a complete track into memory if one had direct access to the disc controller. (Of course, the data was not directly available from this read because it was spread in sectors, but a simple software routine could extract the data from all sectors in that track.) This facility has possibly been removed from the disc control firmware of hard drives because they are usually low-level formatted at manufacture. Dbfirs 08:42, 29 August 2011 (UTC)

The boot process won't be secure unless the BIOS verifies your first-stage bootloader before running it. That means there's code in the BIOS to verify digital signatures and you should be able to use that to verify the next stage. -- BenRG (talk) 06:11, 29 August 2011 (UTC)

I'm assuming you mean a computer that is sufficiently like what we normally call "a PC", right? In that case you have two problems: loading and checking signatures. Firstly loading (neglecting the digital signature part for a second):

• The standard way to work given the BIOS 512 byte load is to load a tiny stub loader (and if we're talking Master boot record loading here, you only have 440 bytes for code there) which uses BIOS calls to load a fuller loader (which can be just about as many sectors as you want). That's what LILO and GRUB do.
• Use a system with Unified Extensible Firmware Interface rather than a BIOS boot, which doesn't have that limitation.
• (At a stretch) add whatever functionality you want to a custom flash image, and replace the BIOS image with that. People have wedged stuff into coreboot, for example.

But, as BenRG says, this is all for naught if you can't verify the first thing you boot. Even with the coreboot solution, if you can change the boot flash image, so can anyone else. And where would you keep your key information - the BIOS flash part is just a memory device, readable by anyone. The industry-suggested solution to this is to use Trusted Platform Module, which stores keys in a relatively secure manner and which performs cryptography and validation. Some higher end desktop and server machines have TPM modules, and it seems many laptops do. But even then, this requires that the flash part be write protected and the boot code therein use an already initialised TPM to verify the bootloader it reads off the disk (see p12 onward in this presentation), which it seems isn't something that's practically available to an end user (cf TrouSerS FAQ). Even if it was, this is of very limited practical utility. TPM is mostly intended to provide a chain-of-trust so someone can trust the integrity of a loaded OS image, not to absolutely lock people out of otherwise generic hardware. Flashes can easily be physically swapped, non-integrated TPMs desoldered, and integrated ones removed by replacing the CPU. Even the original XBox, which went to extraordinary lengths to verify its boot chain (integrating that logic into its custom CPU and GPU dies) was still extensively modchipped. -- Finlay McWalter ☻ Talk 10:20, 29 August 2011 (UTC)

I don't get EFI. Is stored on a separate unit or are parts on the disk as well? And why can't a disk be sectorless? The bit or the byte addresses could just as easily be units of information. Also, smartphones don't seem to use a BIOS or EFI—just a boot ROM. --Melab±1 ☎ 21:54, 30 August 2011 (UTC)

Anyone? --Melab±1 ☎ 13:17, 31 August 2011 (UTC)

EFI is a standard which is implemented by a bootrom, so an EFI compliant loader is almost always in directly addressable flash memory. Disks could be sectorless, and indeed SCSI has "read byte" commands (and so forth). But disks are sector addressed (really they're LBA addressed) because that's the standard that's evolved, mostly to cater for bulk sequential access of whole blocks. How a disk is sectored is an irrelevance for booting, as is the size of blocks. BIOS boots with a 512 byte block because it does, because it's compatible with programs that expect that. It would be trivial to code a bootloader that loaded more data, but that wouldn't be compatible with all the existing bootloaders that work the way they do. EFI throws that compatibility away. No smartphones don't use BIOS or EFI, in general. Some tablets do. -- Finlay McWalter ☻ Talk 13:36, 31 August 2011 (UTC)

To be clear, BIOS is a specification for a type of boot ROM, right? --Melab±1 ☎ 14:21, 31 August 2011 (UTC)

In part, yes. It's also a word that people use generically when they mean "bootrom" (luckily the common usage seems to be adapting to understand the difference, now that people care about how their iPhone or Android phone boots). It's also the standard set of real-mode APIs (implemented via interrupts) that CP/M and DOS programs expected to call to do hardware stuff (a basic set of built-in device drivers); boot loaders still use some of that. And it's a bunch of POST and hardware-discovery and hardware-enable code that's necessary when (unlike a fixed bill of materials device like a phone) the system doesn't know a priori what hardware is installed. The Google Talk the coreboot folks gave is very instructive with regard to all the stuff a PC BIOS has to do before it gets around to actually loading that boot block from the disk. -- Finlay McWalter ☻ Talk 14:38, 31 August 2011 (UTC)

The bootloader could load drivers from each hardware component like BIOS does. I like generic hardware that is as minimal as possible. --Melab±1 ☎ 22:26, 31 August 2011 (UTC)

CSS Full-Height Scrollable Columns

I'm trying to make a layout with three main components: a fixed-height horizontal banner on top, and two columns beneath it filling out the rest of the space. Now, I know that normally I can use a combination of height: 100%, overflow: hidden, and padding to create full-height columns without creating a scrollbar for the page. However, I want the two columns to be full-height and both have overflow-y: scroll, so that they can each be scrolled individually without the entire page having a scrollbar. Unfortunately, the usual column tricks don't seem to work here. If the columns have height: 100%, the scrollbars are able to go off the bottom of the window, even though the column content displays normally; if I try absolutely positioning the columns and force them down with padding, the scrollbars go through the top banner (while forcing them down with margins causing the scrollbars to go off the bottom again). This would of course be easy to fix if I, say, gave the banner a height of 10% and the columns 90%, but I need the banner to have a fixed height. I'm a little stumped as to how to do this without resorting to JavaScript. Obligatory lazy table diagram:

Top Banner
Vertical Column With Scrolling	Vertical Column With Scrolling

71.179.14.98 (talk) 18:04, 29 August 2011 (UTC)

Use 3 divs. I'll call them header, col1, and col2. Make all 3 have position:absolute. Set header.top:0px, header.height:3em (or whatever height you want it to be), header.left:0px, header.width:100%. Set col1.top:3em (or whatever header.height is), col1.bottom:0px, col1.left:0px, col1.width:50%. Set col2.top:3em, col2.bottom:0px, col2.left:50%, col2.width:50%. -- kainaw™ 18:18, 29 August 2011 (UTC)

As he says, you can use both top and bottom properties together, supported in everything but IE6, IIRC. ¦ Reisio (talk) 10:36, 30 August 2011 (UTC)

hibernate a single program

Is there any way to hibernate a single program on a Windows 7 operating system; to save its current state from the RAM onto the disk and resume at a later date? I imagine this isn't a standard Windows feature, but perhaps some third-party software exists that can do this, maybe? 82.43.90.90 (talk) 18:36, 29 August 2011 (UTC)

I'm not very familiar with Windows, but I believe in general the ability to "freeze" a program requires internal support by the program itself. Suppose, for example, that the program has files open at the moment you want to freeze it -- there's nothing the operating system could possibly do to make that work without help from the program itself. Looie496 (talk) 01:23, 30 August 2011 (UTC)

Well, you can just close and reopen the files. There are a lot of gotchas in process hibernation, but there are a lot of gotchas in full system hibernation too. (What if a process had a locked file open on a network drive? What if you hibernate an OS, boot into another, modify the first OS's system partition, then resume it?) The idea is reasonable enough, and similar to process migration, which is actually supported by some OSes.

But I'm not aware of any way to do this in Windows. Microsoft could make it happen, but I'm not aware of any plans to do so. In theory Sandboxie might be able to do it, since the state that would need to be saved and restored is the same state that it has to track anyway. But in point of fact it doesn't support it. VMware and competitors support it, of course, if you think of the whole VM as an app (which is not so unreasonable). -- BenRG (talk) 04:15, 30 August 2011 (UTC)

I, too, reached for VMs when thinking of an answer to this query; I "hibernate" my VirtualBox virtual system all the time. Comet Tuttle (talk) 17:34, 30 August 2011 (UTC)

August 30

Mozila reloading previous sessions

So, I prefer using Mozilla as my web browser for various reasons. But one thing that drives me crazy is that, if I suddenly need to end a session, or if my browser closes unexpectedly (which happens often with this old work cpu I'm stuck with), when I try to open up the browser, it wants to "retrieve" my previous sessions...and I really don't need it to...and it often slows things down greatly, when I could just start a new session and manually reload my e-mail, or whatever I need. So, is there a way to stop it from constantly trying to "retrieve" my previous sessions? Quinn ^{❀ BEAUTIFUL DAY} 00:05, 30 August 2011 (UTC)

Disabling crash recovery AvrillirvA (talk) 00:43, 30 August 2011 (UTC)

Editing .bashrc

Okay so I am running Ubuntu 11.04 and I am trying to edit the .bashrc file so that if I open up a terminal window and type in matlab then MATLAB should run and if I type in mathematica, then Mathematica should run. I opened up the file and added at the end of the file the line

export PATH=$PATH:$Home/Mathematica/Executables:$HOME/MATLAB/bin

When I type in matlab, it opens up fine but for mathematica it says command not found. The location for mathematica is indeed $Home/Mathematica/Executables/mathematica because when I type this whole thing into the terminal, Mathematica opens up fine. I am not familiar with linux at all so I don't know what am I doing wrong. What is the right way to do this? Thanks!128.138.138.122 (talk) 01:21, 30 August 2011 (UTC)

You mean the file is $Home/Mathematica/Executables/mathematica.exe ? Perhaps $HOME wasn't properly defined and this command then propagated the problem ? Try "echo $HOME" before the command in .bashrc (you sure it isn't .bshrc, without the "a" ?), and "echo $PATH" after, to see if it's properly defined, then do the same in the bash window you opened. Also, are both commands performed in the same terminal window (and are you sure that's a bash window, not csh, or ksh) ? As for the one command working and the other not, it's possible one directory was added to the path elsewhere, say as a result of the installation of that program, and that your setting of the PATH variable isn't working at all. Also beware that there are other environment variables for things like libraries, which may also need to be set. StuRat (talk) 01:47, 30 August 2011 (UTC)

Minor points: it probably doesn't have .exe in the name on a Unix system. It certainly is .bashrc; however, the rules for bash's init files are relatively complicated and sometimes you want .bash_login or the environment variable $BASH_ENV. If the command isn't running at all, it may need to be moved. --Tardis (talk) 02:56, 30 August 2011 (UTC)

If you used that text literally, then your problem may be simply that you're using $Home instead of $HOME. --Tardis (talk) 02:56, 30 August 2011 (UTC)

Perfect Tardis, that's exactly what it was. Thanks128.138.138.122 (talk) 20:20, 30 August 2011 (UTC)

wikipedia mirror on my local network.

Let's say I wanted to mirror the entire Wikipedia site, images and all, locally on my home network for private use. I know how to download the wikipedia database dumps and use them offline with various software packages, but these dumps don't include images. Furthermore, I want my mirror to be accessible through a web browser when I point it at a certain IP on my network.

So how would I go about doing this? 209.182.121.46 (talk) 07:40, 30 August 2011 (UTC)

To fully host the dump, you'd need an Apache server with php and the MediaWiki, which you set up and then restore the database into that. Wikipedia:Database download also lists some html based programs for reading them, but for maximum fidelity MediaWiki itself is probably the best solution. Because of the titanic size of the archive, image dumps are no longer made directly available - "Downloading images" on the meta wiki discusses two ways of retrieving them. As the overall size is more than 200 Gbytes, downloading a full archive is a serious undertaking. I'm not aware of a way to obtain a physical disk with all of them on it - to my mind it wouldn't be a bad idea if the Foundation gave (or sold at cost+) physical disks, with at least the entire free image set on it, to libraries and comparable archives. -- Finlay McWalter ☻ Talk 14:04, 30 August 2011 (UTC)

The article on mirroring Wikipedia is Wikipedia:Database download. It includes notes on getting images, and includes tips on setting up MediaWiki properly. Comet Tuttle (talk) 17:32, 30 August 2011 (UTC)

Deleting many files

In a fit of almost Faustian curiosity, I decided to create a few 1-byte files in a temp directory. Where "a few" means about 9 million. The script for doing so, incidentally, is here. On my rather old Linux box (2.6.38, ext3) this is impressively speedy, creating about 5 million files per hour. So that's super then. Now all I have to do is to delete those files. rm wasn't making much impact (even to measure progress I had to write my own "ls|wc" program, which fyi is here). So I've written a custom remover, which does nothing more than a readdir/unlink loop - that's here. But its performance is much slower than creation (by a factor of 30 or so) meaning it'll take about 36 hours to delete all the files. My guess is that each unlink operation involves a seek between the directory inode and the file inode. So:

1. Am I missing some obvious way to wholesale unlink the folder in question (and if necessary have fsck sort it out, surely in less time than 36 hours)? rmdir(2) won't work on a non-empty directory.
2. I can't think of a better way to write the cleanup (it surely does what rm does); is there some obvious improvement to make?

Thanks. -- Finlay McWalter ☻ Talk 13:40, 30 August 2011 (UTC)

The speed of creating/deleting might depend on the number of files in the directory, 9 million is a lot, so it might get faster as more files get deleted. Hopefully... 93.95.251.162 (talk) 15:45, 30 August 2011 (UTC) Martin.

This doesn't answer your question and isn't helpful to your current situation, but you might find it useful or interesting; I've had similar problems deleting thousands of files on Windows 7. My solution is to use a virtual hard disk when writing loads of files. When you want to delete all the files, you just quick format the virtual hard disk or delete the .vhd file AvrillirvA (talk) 16:02, 30 August 2011 (UTC)

In hindsight, a loopback mount would have the same effect with less overhead than a VM. But yes, there's no syscall for hindsight. -- Finlay McWalter ☻ Talk 16:55, 30 August 2011 (UTC)

Using rm * won't work. The shell will try to batch up every filename before starting the delete process. If you happened to put them all in a specific directory (lets pretend it is tmp), then you can delete the directory with rm -Rf tmp. If you want the directory again (but empty), just follow that with mkdir tmp. -- kainaw™ 16:06, 30 August 2011 (UTC)

I was doing rm -f /tmp/f (where f is the directory containing the 9 million), so globbing and the shell isn't an issue. The discrepancy between the count and clean programs (3 minutes vs several days) is really only that the latter calls unlink, so evidently that's where all the work is. -- Finlay McWalter ☻ Talk 16:53, 30 August 2011 (UTC)

It's probable that unlink() is implemented with a more conservative file-system lock, compared to other operations. You can see that there is much discussion on locking for journaling in ext3 drivers: for example, conversion to unlocked ioctl; Improving ext3 scalability (by removing the Big Kernel Lock). If you want faster, you probably need to get off of ext3: consider using ext2, which is unjournaled (and therefore faster and less safe if your power cuts out during a disk operation). More discussion on improving ext2 in Linux 2.5 from LWN. Nimur (talk) 18:34, 30 August 2011 (UTC)

Thanks - you're definitely onto something with regard to the journal. I've booted into a livecd and force mounted as ext2. The same clean program, which ran at around 25 deletes per second, is now running at about 160. It's notable that the disk is much quieter - I expect that's because there aren't seeks back and forward to the journal (with, as you say, conservative locking and flushing of that journal). -- Finlay McWalter ☻ Talk 21:06, 30 August 2011 (UTC) — Preceding unsigned comment added by 81.174.199.23 (talk)

unmount the filesystem, run [[debugfs]] on it, and use the debugfs rm command. It'll be operating directly on the block device so it might be faster. You'll have to feed it a separate rm command for each file, but that should be an easy scripting job. Oops, [[debugfs]] links to an article about something else. I'm referring to the debugfs command that comes with e2fsprogs. 67.162.90.113 (talk) 20:05, 30 August 2011 (UTC)

Thanks, I didn't know about debugfs(8) (or debugfs either, incidentally). As the ext2 mount seems to have made the problem at least tractable I think I'll persevere with it, but I will experiment with debugfs (using my burgeoning collections of stupid filesystem tools) on an unimportant disk (and, as AvrillirvA suggests, nuke it when I'm done). -- 84.93.172.148 (talk) 21:42, 30 August 2011 (UTC) (Finlay McWalter, logged out)

This is a really interesting experiment. I've thought about doing similar things from time to time. I know some FS are better suited for different file types... I'd always heard that XFS was good for large files while others were good at lots of small files. Investigating the unlinking's interesting. What if you mounted the ext3 as ext2 without the journal (I think this is possible right?)? Do you see any difference in speed then? Seems like the journal should be cached in any case. I'm just speculating... this is interesting though. Shadowjams (talk) 07:05, 31 August 2011 (UTC)

Back in the good ol' DOS days there was a utility called qdel.com (I think) that always did that sort of thing way faster than del *.* could ever do (if I remember it was instant with thousands of files and with complex tree structures which DOS had problems with). It might be worth it to track this util down and disassemble it to see what it did... since we're on the path of masochistic, pointless things to do with computers! Sandman30s (talk) 16:35, 1 September 2011 (UTC)

Digital Pens

help me in finding the components used in DIGITAL PENs, type of sensors used and the working of DIGITAL PEN — Preceding unsigned comment added by 117.204.7.109 (talk) 15:47, 30 August 2011 (UTC)

Are you referring to Tag (LeapFrog)? -- kainaw™ 16:01, 30 August 2011 (UTC)

Or maybe a digitizing pad or light pen ? StuRat (talk) 21:57, 30 August 2011 (UTC)

Microsoft Word length

Hi. Is there a maximum length or size, either in number of pages or total kilobytes of information that any Microsoft Word document cannot exceed in order to be retrievable or saveable? Does this vary based on the version (2000, '03, '07, etc.)? Is this dependant on presense of images? Thanks. ~AH1 ^(discuss!) 16:20, 30 August 2011 (UTC)

It does depend on the version. It's also a little more complicated than "maximum file size," because of the way that modern Word documents are stored. For example, if you insert text, you can place a very very very large amount of it in the document: something like 32-million-character-elements (roughly 2000 pages of solid text). You can also include formatting, content markup, and so on, for a file-size up to 512 megabytes. More complex features, like images, text generated by macros, or content imported as a sub-document, do not count toward these limits do not apply. For a comprehensive listing, see Operating Parameter Limitations and Specifications for Word 2010.

For comparison, here is Operating Parameter Limitations and Specifications for Word '97.

If you are creating Word documents that are arbitrarily large, you should invest some time to learn the advanced features of Microsoft Office: particularly, soft-linking to content in sub-documents: Create a master document and subdocuments. This technique will allow you to create arbitrarily-large documents. Nimur (talk) 18:37, 30 August 2011 (UTC)

Second most popular non-commercial site

Wikipedia.org is one of the world's most popular websites as ranked by Alexa. Wikipedia is managed by a non-profit organization, the Wikimedia Foundation. Most popular websites are owned by for-profit enterprises. What is the second most-popular website owned by a non-profit organization? Is it #202 on Alexa, the Internet Archive? I read the list and did not check every site, but that was the first one that stood out to me. Alexa list Blue Rasberry (talk) 16:57, 30 August 2011 (UTC)

The BBC is at #39, if you consider that a "non-profit organization". -- Finlay McWalter ☻ Talk 17:12, 30 August 2011 (UTC)

Automatically getting a file's parent directory in Windows 7?

In OS X, if I had a PDF open in Adobe Reader, I could Command+Click on the filename at the top of the window, and it would allow me to see its entire file path and quick jump into a Finder window of the directory it is in.

Is there any equivalent in Windows 7? If I have a file open in a program, is there any instant way to know its full file path and open its parent directory? (Other than going to Save As, and then looking for the directory there, then going back into Explorer and navigating to it manually.) --Mr.98 (talk) 18:09, 30 August 2011 (UTC)

This is really more up to the creators of the application, and not so much Windows. Some programs might do it, but some might not.
In many programs, going to File -> Properties might be an option, which would likely list the file location. TheGrimme (talk) 14:48, 31 August 2011 (UTC)

In the Save As dialog box you could right click on the current folder (in the directory tree pane) and choose "Open in new window", or press Alt+D to select the directory name in the breadcrumb bar and Ctrl+C to copy it to the clipboard. -- BenRG (talk) 18:24, 31 August 2011 (UTC)

Home directory physical location when running a Linux Live CD

Where does your home directory physically exist when you're running most Linux Live CDs from the CD/DVD drive of your computer, assuming you don't partition any space on your computer's hard drive for it? Are most Live CDs these days on R/W discs and you have space on the disc for leaving stuff, or does your home directory only exist in main memory while you're running the CD (again, assuming you can't touch the HDD) and disappears if you don't save it somewhere before powering down? 20.137.18.50 (talk) 18:55, 30 August 2011 (UTC)

It varies between distributions! But you can find out! Open a shell and type:

df ~

This will call the df utility program, and tell you the file-system of your home-directory, and the device it is mounted on.

Debian has extensive documentation: initramfs is used for boot-up; some live CD distributions may keep it around for temporary use. Nimur (talk) 19:30, 30 August 2011 (UTC)

Debian and related distributions (including Knoppix and Ubuntu) use aufs to perform a union mount with a read-only image of the boot media underneath and a writable (but mostly forgotten-on-boot) filesystem in RAM overlaying that. note to self: much generic info in UnionFS should be moved to union mount So most of the time when you read a file you're reading it from the CD, but when you create a file, or change an existing one (even one that exists on the non-writable disk) you're writing into the RAM overlay. Some livecds have a mechanism to write off the home directory to a writable nonvolatile store (usually a flash disk) on logout. By and large, you can't write to a R/W disk randomly or quickly, so it's not suitable for implementing a proper read/write filesystem. -- user:Finlay McWalter (logged out) — Preceding unsigned comment added by 84.93.172.148 (talk) 21:27, 30 August 2011 (UTC)

August 31

Do I have Bitcoin straight in my head?

I'm trying to wrap my head around Bitcoin. I get the part about having a wallet with coins in it and then spending the coins on real world merchandise. What I'm not sure about is the "mining". Do you get more bitcoins by basically solving various math problems (simplification, I know) and then presenting the result? So basically, you're being reimbursed for your processor churning away at problems? Sort of like a distrbuted computing effort like Folding@Home. Right? So then, following that logic, basically the millionaires of the bitcoin economy will be whoever can devote the most computing power to their wallet? Dismas|^(talk) 07:32, 31 August 2011 (UTC)

No. If I am not mistaken, those Bit-millionaires purchased (or mined) large amount of Bitcoins early on before their prices skyrocketed. According to bitcoincharts.com, in 31 August 2010, you can purchase one million Bitcoins for a mere $60,000. Moreover, back then, the Bitcoin "mining difficulty" parameter is far lower than today, allowing those Bit-millionaires to mine large amount of Bitcoin without expensive hardware (GPGPU, FPGA, ASIC, ASCI, etc.) 118.96.155.202 (talk) 11:44, 31 August 2011 (UTC)

I don't see how that answers my question. I'm not asking about Bitcoin millionaires. I'm asking about people earning Bitcoins now. Today. What is involved in this mining thing? I've read our article and it makes no sense to me. Dismas|^(talk) 14:01, 31 August 2011 (UTC)

In all fairness, you do ask about Bitcoin millionaires of the future in the last part of your question. What 118.96 was saying is, "even though you can 'mine' coins, the people who are actually going to be rich are going to be the ones who have probably not spent their time mining coins, or certainly won't be in the future." But yes, essentially your understanding of the "mining" process is correct. Except that the problems aren't, to my knowledge, actually useful ones. The question is whether anyone who spends their time mining will really end up with much — I suspect that mining is not a terribly lucrative affair, from reading the article. It's sort of the minimum wage of Bitcoin, which will generate resources, but probably not at a pace that makes it actually very useful. --Mr.98 (talk) 14:28, 31 August 2011 (UTC)

The purpose of "mining" is because the bitcoin economic theory is predicated on a steadily increasing quantity of money in circulation. In order to control the rate of introduction of new money, the bitcoins must be "mined" - i.e., must use a certain amount of computational effort. It is very closely related to the concept of the proof-of-work system.

The real question you should ask is not why the mining takes place in the form of solving-a-useless-math-problem. The kernel of your question is, "what economic sense does it make to intentionally increase the quantity of money in circulation?" I don't know that it makes any sense. It will result in inflation, i.e. the same tangible good will cost more bitcoins, several years from now. In order to counter that inflation, the bitcoin designer intentionally prints money - resulting in more inflation. I have a suspicion that the innovators of the bitcoin economy spent more time on cryptographic implementation details than they did learning economic theory. Money creation is the relevant article. Rather than having a central bank who mints new money by printing paper fiat-currency, the bitcoin scheme is distributed, and the "mining" represents proof of work completed, in order to regulate the amount of money you may print per unit of time. Nimur (talk) 18:08, 31 August 2011 (UTC)

For a long time I was curious whether I was just daft and missing something, but I'm pleased to see that others think it is an economically problematical thing as well... --Mr.98 (talk) 18:25, 31 August 2011 (UTC)

In my understanding (and I'm not an economist), the idea is to solve the problem of initially distributing the currency. The "natural" thing to do is to have the originator of the system declare at the beginning "There are 1 trillion bitcoins. You can buy some of them from me, by sending me US dollars/Euro/Zimbabwe dollars." But that sounds a lot like a scam. So, they made it possible to get bitcoins without enriching the organizers of the system. Paul (Stansifer) 22:03, 31 August 2011 (UTC)

Does the browser or the server look for "index.html"?

In "Fluency with information technology" Chapter 3 page 98-99, it says that when I point my web browser to http://www.example.com/example/ the browser will automatically look for http://www.example.com/example/index.html and display that if it exists. However, is it really the browser that does this for me, is it not the server that serves this page because it assumes that is what I'm looking for? 83.250.156.56 (talk) 12:14, 31 August 2011 (UTC)

It is the server that does the job of picking the file to show. In IIS you set a priority list of names to look for and it will pick the first one that matches. Another way to behave is to give a directory list instead of a file. Or it could give an error message to say no file. Graeme Bartlett (talk) 12:33, 31 August 2011 (UTC)

Depending on the configuration of the server, the paths may not even correspond filesystem paths (for example, pretty much all of Wikipedia's website is like this), in which case looking for an "index.html" is meaningless. Paul (Stansifer) 12:52, 31 August 2011 (UTC)

As mentioned above, the server is responsible for choosing which file to serve. In fact, many times you may have multiple index files (index.htm, index.html, index.php), in which case the server has a (configurable) order of prioritization for which type to serve.
For some extra reading, as mentioned at by Paul, there are server extensions such as mod_rewrite which appear to be serve files/folders, when in fact don't exist on the server at all! TheGrimme (talk) 14:54, 31 August 2011 (UTC)

Thank you all for your answers, so I think we can agree that this expensive book is flat-out wrong. I will read the rest of it with caution. 83.250.156.56 (talk) 18:42, 31 August 2011 (UTC)

Digitise my life: step one - acquire a scanner

Hello fellow ref desk people. I hang out mainly on Language, Miscellaneous and Humanities, where I've just contributed an answer with an academic quotation, personal knowledge, and internal links to our articles. While composing that response, it occurred to me that I should ask for help as well as giving it. So, if this question is too over-arching to be properly answered here, if I am transgressing the boundaries of this desk, my apologies; responses at my talk page would be just as welcome. Here goes:

I need to digitise my life, and the first and largest task is getting rid of paper, both my own documents and books. To that end, I have determined that I need to acquire a scanner. I've never had one, and looking at consumer review websites such as Reevoo has proven a bit overwhelming, as I can't match up what I think I need (which is in any case open to discussion) with the 121 items listed. In some cases it isn't even clear whether the scanner is a flat-bed, which wouldn't really help when I have thousands of pages that need to be processed.

1. What key words do I need to be looking for, or key features for that matter, in the scanner itself?
2. What kind of software should I be looking for? Is it easy to save a scanned document both as an image (pdf, or are there better alternatives?) and as a searchable (and alterable) text file? (Or can image files be searched for text these days? I am no expert on what software is capable of.)
3. How can I organise this huge amount of material so I can find the documents I need, while only half-remembering phrases within them? My preference is to store the material online, but I am aware that services such as Dropbox can change their T&Cs and attempt to "own" my material. What are my alternatives for storage?
4. Is it necessary to buy a new scanner, or can I lease one for a couple of months? (I am in the UK.) Are second-hand ones notoriously unreliable?
5. There must be people who've already digitised their lives (not just paper, but old music and photos too). Are there blogs or websites you can recommend, or advice elsewhere on tackling a big personal project like this?

I am not going to succumb to the temptation of doing a Princess Leia ("Help me, Computing Refdesk; you're my only hope") -- what scanner should I get, what is the best software, etc. But at least I can ask, how can I determine what scanner to get, how can I choose intelligently among the software available, etc.

OK guys, do your worst. Many thanks! BrainyBabe (talk) 15:21, 31 August 2011 (UTC)

Consider a ScanSnap S1300 from Fujitsu. Google 'scansnap s1300' for lots of reviews and one or two websites that are dedicated to the Fujitsu scanners. It has an automatic sheet feeder (cannot do bound books) and handles 8 ppm. It is delivered with OCR software for both PC and Mac, scans both sides of the page at once, can produce searchable PDFs using OCR, and costs between $200 and $300 US. I first became aware of these scanners per a Dave Winer review. EdJohnston (talk) 15:40, 31 August 2011 (UTC)

Scanning books yourself is, for the most part, bonkers. A consumer grade flatbed scanner takes ~30 seconds to scan each A4 exposure. So, with time for manual pageflipping and breaks, it'd take you most of a day to scan a paperback you paid a fiver for - that's an astonishingly poor use of your time. Automated book scanners will do it in a couple of minutes, but are very expensive (they're intended for libraries and archives). Office-grade scanners (which are essentially digital photocopiers) can scan much quicker (maybe 1 or 2 seconds per side) but are still large and expensive, and to scan a book with them you have to guillotine the spine off (and render it a loose collection of sheets) so you can put it through the sheet-feeder. Commercial scanning companies can do this kind of thing, but for reasons of copyright they won't do your book collection, and it would still not be at all cost effective. If you must have electronic books, it's be easier and cheaper to just buy them new as ebooks for an ebook reader like an iPad or Kindle. And have fun reading their terms and conditions, to see if you're really buying the book, or somehow acquiring a licence to read it under certain circumstances. -- Finlay McWalter ☻ Talk 15:42, 31 August 2011 (UTC)

What are these automated book scanners that can scan a book in a couple of minutes? Even with destructive scanning (where you just gut the pagers and run them through a feeder) it's going to take longer than that. I'm not sure you're going to find a scanner that operates faster than a current photocopier does. --Mr.98 (talk) 18:19, 31 August 2011 (UTC)

Kirtas Technologies claims up to 2900 pages per hour with their fanciest automatic scanner; that would polish off my copy of The Catcher in the Rye in under 4 minutes. Video of a slower Kirtas scanner (running at about one page every 5 seconds) is here. This experimental scanner runs at 200 pages/min (which would be 12,000 pages/hr if you could sustain it). These high-speed scanners all rely on high-resolution high-speed photographs rather than dragging a scan element over the page (or the page over the scan element), and use a known mapping pattern to reconstruct the page geometry so they can reverse the distortion caused by the page not being flat. Google's "maze" pattern for their scanner is discussed in this patent. I don't know how fast Google's scan is (I believe they use their own equipment, at least for non-special books). Some people have experimented with blown air to separate and flip pages faster than mechanical arms can safely do alone (patent) but I don't know if anyone has commercialised that (getting it 100% reliable, where it doesn't occasionally skip stuck pages, sounds hard). -- Finlay McWalter ☻ Talk 19:42, 31 August 2011 (UTC)

If you have a large collection of papers (say legal and financial stuff) it's best to approach your local document imaging company (in the yellow pages under "documents" or "photocopying") and they can shove that stuff through their high-quality sheet feeders, give you a DVD with PDFs on it, and charge you for labour. If you need to retain this stuff for legal (e.g. tax) reasons you probably still should keep the paper documents somewhere, and (as with all digital stuff of any value) you need multiple redundant backups in different physical locations. -- Finlay McWalter ☻ Talk 15:49, 31 August 2011 (UTC)

You'll also need some sort of OCR software for "reading" the images.Smallman12q (talk) 17:35, 31 August 2011 (UTC)

To clarify: OCR software makes PDFs searchable. You can read PDFs without them being OCR'd. --Mr.98 (talk) 18:19, 31 August 2011 (UTC)

It seems very unlikely to me that DropBox either would claim ownership of uploaded material, or could get away with it. Most likely is they will claim you give them a limited license to copy it for the purposes of uploading (just so nobody can charge them with copyright infringement for holding copies of your stuff for you), but that's probably it. I don't think Dropbox is a bad option if you want to keep a lot of files synced between computers. --Mr.98 (talk) 18:22, 31 August 2011 (UTC)

Hi everyone, OP here, thanks so much for the answers so far, and please keep them coming. Thank you EdJohnston for the ScanSnap recommendation; I've been reading about it, and looking on YouTube, and it seems to sync well to EverNote, which I've used a little (but only a little). That would be one answer to question 3 re storage. To clarify, Finlay McWalter, yes, I was considering guillotining some of the out of print books, to make them scannable quickly, with a machine that accepts chapter-long chunks. So, a bit bonkers, but not entirely: I don't (yet) own an e-reader, and it leaves a bad taste to be asked to pay again for an electronic version of a book I already have forked out for. (I am very aware that this issue will look completely different in ten years' time, but I am facing it now and need to deal with it with today's tools and work-arounds.) I have a related question re OCRing: once a document has been scanned in, how easy is it for me to extract the data in order to change it? I have quite a few print-outs of documents I wrote, but I've lost track of the digital file. I want to scan them in to re-capture them, manipulate them, bring them up to date and re-use them. Is this what OCR is about, or have I got the wrong end of the stick? BrainyBabe (talk) 19:40, 31 August 2011 (UTC)

It is not easy to manipulate or change scanned in data. Basically the computer sees it as an image. OCR helps the computer understand that the image contains text, which make it searchable. Now in theory if it is searchable you could also copy and paste it into, say, MS Word or something like that. But the problems are that 1. the OCR isn't perfect, so you spend a huge amount of time picking out typos whenever you do something like that, and 2. OCR is just awful at figuring out formatting, which means your pasted in text is usually a huge mess. So in my experience it's rarely time efficient to scan, OCR, paste, and clean up — it's usually not any better (and in some ways more difficult and frustrating) than just retyping (or paying someone else to retype) the originals. (The difficulty and frustration comes from typos and errors, some of which are very hard to spot, like when your lower case L's render as 1's or vice versa.) I think of PDF scans as being convenient, searchable photocopies — not anything like editable documents. --Mr.98 (talk) 20:31, 31 August 2011 (UTC)

(ec)Regarding editing: I've most experience with ReadIris PRO (but I don't especially recommend it, as I haven't used others and maybe they're better). In addition to annotating a scanned PDF with invisible text in the background (allowing the PDF to be searchable) this will generate Word documents using one of two strategies. One is to try its hardest to reproduce the actual physical format of the document - to do this it uses lots of awkward little text frames positioned just so on the page - you get the page pretty much verbatim, but it's a bit painful to make changes. The other strategy eschews formatting acuity for editability, producing a regular word document with normal paragraph separators - this doesn't physically resemble the scanned document much, but the text is in a straightforward format. OCR is pretty reliable when dealing with reasonable resolution scans of decently printed material (reasonable, but not perfect), and its good at handling text and basic numbers. But feed it stuff where format is meaningful (like tables) and it tends to fall apart. Part of the reason for its success is that you tell it (or sometimes it tries to infer) which natural language the text is written in, and it runs all the text its recogniser emits through a dictionary - as with any such automatically-fix-errors strategy, it takes badly to unfamiliar words and particularly words or names in foreign languages. So OCR is certainly preferable to typing the text in again, it can't be completely relied upon to reproduce many documents absolutely verbatim. -- Finlay McWalter ☻ Talk 20:36, 31 August 2011 (UTC)

One thing to consider when buying scanners is the duplex mode. The cheapest scanners have no document feed at all: you have to place each document on there by hand - that's obviously a lot of work if you're doing more than a few pages. Next up are half-duplex feeders, which feed one side of each sheet past the scan element (like the way paper feeds though a cheap home printer); so if you had an 8 page book, the scan would just have pages [1,3,5,7]. If you flipped the stack over and rescanned you'd get [8,6,4,2], and hopefully the scanner would come with some software that reordered and zipped these together to make [1-8]. Next up is a mechanical duplexer (which a lot of office photocopier-type equipment has). This feeds one sheet through, scans it, then sucks the sheet back through a mechanical thingy that does a 3-point-turn and delivers the reverse surface for scanning - this is very impressive when it's going (and the expensive machines that professional document companies have can run at some scary speeds) but it's a bit Heath Robinson-ish, and may not be suitable for the cheap paper on which some books are printed. Lastly there's the kind that has a simple once-through paper path but has two scan elements (one on each surface) and the software brains to scan both sides concurrently and then emit the pages in the right order. If you're guillotining books, and don't consider clearing paperjams to be a hobby you're interested in pursuing, this last approach seems the simplest for you. The Fujitsu machine EdJohnston recommends works this way. -- Finlay McWalter ☻ Talk 21:04, 31 August 2011 (UTC)

Net Access

This was originally posted to Wikipedia talk:AutoWikiBrowser, but it seems like it belongs here instead.

My computer says I am connected to the internet...yet when I try to load a page it won't load. I can use skype but nothing else loads. Safari starts to load the page but I only get a spinning wheel. I have tried on multiple computers and my PS3 and no pages will load. It started today 30 Aug 2011. Is anyone else experiencing this issue? And how do I fix it? I am using Talk Talk and in the UK.. Thank you — Preceding unsigned comment added by 68.56.111.114 (talk) 17:10, 30 August 2011 (UTC)

If you connect through a router, it may have mismanaged the local IP addresses it assigns to your computers. Try turning the router off and on. Certes (talk) 20:56, 31 August 2011 (UTC)

Your computer may also be set up to use a proxy you cannot access. Check the proxy settings. Also try if you can ping the real net (open a terminal and type e.g. 'ping www.google.org'). Finally, you may have trouble with DNS. Try 'nslookup www.google.org'. --Stephan Schulz (talk) 22:23, 31 August 2011 (UTC)

pcie half card with Wimax and WiFI

I've found several out of date cards that offer this dual capability. What is the latest card that has this dual capability? --DeeperQA (talk) 21:54, 31 August 2011 (UTC)

Telecommuting programming job boards?

What are the best web sites for hiring programmers for remote project-based work? I know about http://odesk.com and I remember reading about some others but can't find them now. 76.254.20.205 (talk) 22:53, 31 August 2011 (UTC)

I'm afraid I can't say which are best, but per the article on oDesk, there is also Elance, Freelancer.com, Guru.com and VWorker. --Kateshortforbob _talk 13:28, 1 September 2011 (UTC)

September 1

Acrobat bug or feature?

We upgraded Adobe's Acrobat Standard (i.e., not just Reader) from V7 to V9 in June, and are suffering from a new behaviour which we are unable to define as a bug, a feature, or a something else. Perhaps one of you has experienced this also and has advice for us.

We're on WinXP, and I'm fairly confident that that's irrelevant.

We frequently use Ctrl-C, Ctrl-V to copy-and-paste a couple dozen individual values (one at a time) from a local application into a fillable PDF form -- back and forth between two windows, clicking on title bar or taskbar icons to swap focus. With this recent update, the PDF form appears to retain focus "where we left it" -- the cursor IS in the desired field -- but in fact the form refuses to accept data at the cursor.

• This is the case both with keyboard entry and click-to-focus-plus-ctrl-C.
• This is the case both with PDF-in-a-browser and PDF-in-a-standalone-Acrobat-window.

In order to paste the copied data in the form, it is necessary to click the cursor in a different field than the most recent one, then click back into the desired field -- at which time Ctrl-C works as expected.

So, Is this a bug, or a feature?

• I've gotten nowhere on Adobe's Support site, but I'll admit my problem description may be the worst I've ever written. Perhaps better search keywords would give better results!
• Tech support for the source application says they've never heard of it, so "it can't be our problem".

Might it be something configurable within Acrobat?

Thanks! --DaHorsesMouth (talk) 00:22, 1 September 2011 (UTC)

P.S. Anyone who would like to suggest we move to laserapp as a solution to ths problem, please keep it to yourself :-)}

I suppose you've already tried doing this on a new build and profile? Where I work we get all sorts of strange adobe issues which are fixed by wiping the adobe folders in the user's profile. Vespine (talk) 04:42, 1 September 2011 (UTC)

Can't add a font on a Mac

I'm trying to install a font, Decker specifically, on a Mac running OS X 10.6. No matter how I do it, the font won't install. I've tried double clicking, I've tried opening Font Book and installing through the menu. Everything. This font will not be listed anywhere and can't be used in Photoshop or anywhere else. Any ideas what's going on? Dismas|^(talk) 03:27, 1 September 2011 (UTC)

• Copy font files to ~/Library/Fonts. Start a program you wish to use the font in. Fifelfoo (talk) 03:35, 1 September 2011 (UTC)
  • It's already there. The bold version as well. Neither one of them show up in any program (Word, Photoshop, etc). Dismas|^(talk) 03:47, 1 September 2011 (UTC)
    • Logout/login or rebooted? What format is the font file? Fifelfoo (talk) 03:49, 1 September 2011 (UTC)
      • Rebooted. ttf file. Dismas|^(talk) 03:53, 1 September 2011 (UTC)
        • Weird. this article on cache clearing might be of help? Fifelfoo (talk) 04:39, 1 September 2011 (UTC)
          • Done. Still no joy. Dismas|^(talk) 11:59, 1 September 2011 (UTC)

Any possibility that the file is corrupted? --Mr.98 (talk) 11:49, 1 September 2011 (UTC)

I suppose but I downloaded the font from the same site to my Windows XP machine at work and it installed fine. Dismas|^(talk) 11:59, 1 September 2011 (UTC)

I just reloaded it. Re-installed it. And it still does not work. And if anyone is wondering, yes, the project requires this font. Dismas|^(talk) 12:27, 1 September 2011 (UTC)

Nice programming language to play with?

Hmmm... I guess I just need a new hobby. Anyways can you name a programming language that is:

• Free and can be freely downloaded from the net (bonus points for having a small size)
• Manuals and tutorials are available online (bonus points for offline books)
• Always updated and used by the software industry
• I can use to write games with (not Blizzard level of course)
• can be run and used in Windows (I know everything runs on windows but I want to be sure ;) )

--Lenticel ^(talk) 03:51, 1 September 2011 (UTC)

C# satisfies all the above. I like it a lot. I need to note with regard to your first bullet that every "programming language" is by definition free, because languages can't be copyrighted. Any particular company's compiler or development environment or IDE or whatever can be closed-source, of course. Comet Tuttle (talk) 05:28, 1 September 2011 (UTC)

Python and Racket/Scheme, my two favorite teaching languages, both meet all those criteria. They're not widely used by the software industry, and while Python has Pygame, writing games in Racket will be kind of a pain (but don't let that dissuade you; learning multiple languages is really important). Peter Norvig's essay on learning programming has resources for both of those languages at the end. Paul (Stansifer) 13:09, 1 September 2011 (UTC)

Every reasonably well written "how to program" book that I've seen comes with a language compiler that you can install on your computer. So, it is a matter of picking a language, picking the book, and you got it. -- kainaw™ 12:48, 1 September 2011 (UTC)

Perl is similar to Python. It is not the latest technology but major companies use it commercially and it is actively being developed. ActiveState provide a Windows installation here. The CPAN library here has 897 open source modules to assist with writing various games, mainly aimed at strategy rather than shoot-em-up. Certes (talk) 15:53, 1 September 2011 (UTC)

Is Perl ever used to write games? This is one of Lenticel's requirements. I'd say that C# or Java (they are closely related) would be a better choice - I'd go for Java myself, but then I'm adverse to using anything that Microsoft are involved with if there is an alternative. AndyTheGrump (talk) 16:31, 1 September 2011 (UTC)

Is Microsoft Office shareware?

Is Microsoft Office shareware? The article says that it is. Bubba73 ^{You talkin' to me?} 05:33, 1 September 2011 (UTC)

Yes - you can download a 60 day trial version from Microsoft. Nanonic (talk) 06:59, 1 September 2011 (UTC)

It isn't Retail software? (It is listed there.) Or Commercial software? Perhaps the free trial can be considered freeware, but what about after the free trial period? Bubba73 ^{You talkin' to me?} 15:32, 1 September 2011 (UTC)

It is many things. These marketing names are not exclusionary. -- kainaw™ 17:06, 1 September 2011 (UTC)

HTPC servers

How do you actually get HTPC servers like MediaPortal to be displayed on a TV? I got a Toshiba 42VL863. So far all I could manage is to listen to a single song through XBMC after finally realizing that it should be added to a library, but still no idea how the software itself is displayed on a TV (I assume it runs on a PC, and not directly installed on a TV). It's connected through ethernet, but the PC and TV aren't directly connected through anything else, and I'm not sure if that's needed. I'm assuming it's not a networking problem as I was able to listen to the song on the TV, and the same on my smartphone which only has wifi. 62.255.129.19 (talk) 11:24, 1 September 2011 (UTC)

Excel Macro

I have an Excel 2007 database with a different tab for each month (Jan, Feb, Mar, etc.) and one tab for "Data Entry". I want to be able to enter all my data in one column on the Data Entry tab and have a macro copy it from the Data Entry tab to the appropriate month tab. For example, on the Data Entry tab, I will have a column of text from B2 through B40. I will enter the month "Jan" in B2 and I want the macro to copy B3 through B40 from the Data Entry tab and paste to the Jan tab. To make it more complicated, I can have several columns of data on each month tab, so when it pastes to the month tab, it needs to go to the next blank column to paste the data. Can anyone with coding expertise help me out? Tex (talk) 13:07, 1 September 2011 (UTC)

I am sure there will be situations where you will want to change your data after you have entered it. So why not just do data entry straight onto each month's worksheet ? Otherwise, to allow data amendments, you will have to build a macro to retrieve a particular column for a particular month - and by the time you have done that, you have almost built a database engine in Excel, which is not what it is intended for. Gandalf61 (talk) 13:23, 1 September 2011 (UTC)

Where to start with creating graphics?

Riiight... I fail massively at creating any sort of graphic art or animation, on paper or on screen. Literally not capable of producing a stick man in Windows Paint, it's that bad. But it seems like everyone has their own deviantart, or Newgrounds, or Youtube channel.... and I'm thinking I might be missing something. I don't think I have any hidden creative talents, so feel free to tell me I just shouldn't bother. But. I would like to know how to draw some basic things on a computer. And perhaps very gently molest other people's artwork. Can you guys suggest a good place for a complete newb to start? I can read and follow instructions but that's it.