Wikipedia:Reference desk/Archives/Computing/2009 October 8

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October 8[edit]

Question by IP user[edit]

a. How should we change the global alignment algorithm to compute the hamming distance between two strings?

b. How should we change the global alignment algorithm to compute the longest common subsequence of two strings?

c. How should we change the global alignment algorithm to compute the best approximate match between a given pattern and a text? —Preceding unsigned comment added by (talk) 00:11, 8 October 2009 (UTC)

Pictogram voting delete.svg Please do your own homework.
Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know.

Facebook wall post[edit]

In facebook when a link is posted to my wall to (for example) a photo album from one of my friends, even people that don't know that person are able to view the album (and if I am tagged they will have access to the whole album even if it is set on "friends only"). It's not exactly a security hole, but I don't want to promote this "exploit", so I regularly delete such links on my wall.

But... when I make comments on peoples albums and posts, it always leaves a link, and deleting every single one of those is a real pain. Besides, I don't really want everybody to know where every single comment I make is.

Is there a way to stop posting these "own comment" links on the wall? Thanks! (talk) 02:31, 8 October 2009 (UTC)

Look at your privacy settings. I have made it nearly impossible for people to find me on FB, and when I comment on a friend's post, all their friends see is black text bearing my name - no link unless you are already my friend. As for tagging photos, I don't know if that's in the security settings or if you have to manually undo that. Falconusp t c 04:09, 8 October 2009 (UTC)
Yeah, I'm aware that you can make it really hard to do anything, but I really only have problems with this specific issue: I don't want to be completely detached. (talk) 02:36, 9 October 2009 (UTC)
Under "Privacy Settings" select "News Feed and Wall" and from there you can untick the options you don't want it to show, specifically comment on a photo in your case. Regarding what you said about the exploit for viewing someones whole album, that's not actually a bug. The default permissions when creating an album are "Everyone" (it's on the main page when creating the album) and the person can choose to change it to "Only friends" or whatever, but by default literally anyone who can access any picture in the album can access the whole album - It's up to the user themselves to restrict the album if they want to. ZX81 talk 02:54, 9 October 2009 (UTC)
Oh wow I missed a whole menu! Thanks that's exactly what I was looking for! Yeah I'm aware that it's not really a bug, it's more like a silly setting that people aren't really aware of how open it is! Thanks a lot! (talk) 14:50, 9 October 2009 (UTC)

Restoring default settings of Windows XP so programs can be viewed[edit]

I accidentally changed my computer to make all programs hidden or something. I've got an HP running Windows XP. When I go to Start at the lower left, only AOL shows up, not MS Word or the other programs thta I had recently accessed. There are almost no programs appearing under "All Programs" where once there were a few dozen. The folder marked "Startup" is empty.

I'm pretty sure they're just invisible. How do I restore them?

Signing off for tonight, I figure there will be an answer by morning. I have another query below, that's unrelated. (talk) 02:55, 8 October 2009 (UTC)

Um... What exactly did you do? Falconusp t c 04:07, 8 October 2009 (UTC)
Sounds like you deleted the Windows/Start Menu folder. Check the Recycle Bin. ---— Gadget850 (Ed) talk 10:31, 8 October 2009 (UTC)
It's not in the Recycle Bin Also, sorry, but this crazy computer changed IPs on me. Weird. (talk) 12:04, 8 October 2009 (UTC)
I clicked on "hidden," then clicked aply, thinking it wouldn't hide things, I guess, i don't know. Then I unclicked "hidden," so the box was blank again, and pressed "apply" again. But, nothing happened. (talk) 12:04, 8 October 2009 (UTC)
Fixed and Gadet850, you kind of gave me a hint, anyway.
I searched for the Start Menu folder int he Search function under the start menu, saying to look for hidden folders. It was pale (i.e.: not full color) showing it was hidden. So, I right clucked to get its properties, then unchecked the hidden box and told it to aply that to all subfolders, too. I did that in a couple other places, as well.
Thanks to all who tried to help. (talk) 12:33, 8 October 2009 (UTC)

"Settings" on AOL not viewable[edit]

Why would "Settings" on AOL not be viewable when i'm online? I can't access it to clear my browser window, which is really annoying me, though I can clear my footprints. Thanks. (talk) 02:57, 8 October 2009 (UTC)

I haven't used AOL browser in years, so I can't say; I honestly suggest downloading another browser if you want to clear your tracks, or use the IE that's preinstalled on your computer (unless you happen to have a recently purchased copy of the EU version of Windows). Magog the Ogre (talk) 14:51, 9 October 2009 (UTC)
Thanks - the problem has been solved. Apparently I opened a really old version of it by mistake. (talk) 12:14, 10 October 2009 (UTC)

speed of ARM Cortex[edit]

I see Ti has announced a 2 ghz, dual core ARM Cortex processor. How fast is that in x86 or SPEC-like terms? I'm having trouble finding any general purchase benchmark results. Thanks. (talk) 07:57, 8 October 2009 (UTC)

There hasn't been much competition that way so far as most ARM users have been more concerned about power consumption and cost and have a central application they can benchmark to see if it goes fast enough They might have narrow memory or a slow ROM. They might be using floating point or multimedia instructions. They might buy in specially crafted code for important bits or hand code a central loop. Interrupt latency may be an important consideration. It all depends and it isn't as easy as just comparing one PC to another -and you know how they can vary depending on if you're a gamer or a commercial enterprise wanting a database server. ARM do support the EEMBC coremark though and according to that it competes very successfully in performance/MIP performance/Mhz per core terms with the latest x86 processors. Dmcq (talk) 09:24, 8 October 2009 (UTC)

Motion Flight Simulator Synchronization[edit]

Hello. I am hoping someone can point me in the right direction. I've hit a wall and am unsure what to do.

I am in the process of building a motion simulator (2DOF). I am currently running Flight Simulator X as the simulation software. The base is fully hydraulic and the cockpit sits on top of a bidirectional plate. The hydraulics are linked to the yoke so pull/push will move the cockpit up/down and twisting the yoke provides movement side to side.

Potentiometers are installed on each axis and hooked up to a Leo Bodnar Interface board which is recognized in FSX as a controller.

My issue is that the cockpit movement is NOT synchronous with the visual display, especially on the ailerons axis. There is a significant delay between me moving the yoke (cockpit) and it's visual representation on screen.

Note this simulator is entirely active. There is no feedback from the simulator back into the cockpit to control motion. The pilot dictates every move. I've been through the aircraft config and .AIR file a countless times. Some settings help but it is not exact.

So my question is, is there a way to sync my control movement with what displays on screen? I appreciate any help! —Preceding unsigned comment added by (talk) 13:59, 8 October 2009 (UTC)

This project sounds sufficiently complex that it is unlikely your description is complete enough for us to answer it. Certain prominent Reference Desk contributors have worked on commercial flight simulators - but I expect they will tell you the same thing. Can you narrow down the trouble? Really, this sounds like it needs a lot of engineering expertise and time - I don't think you'll get a useful answer from a bunch of reference desk responses. At the core of the issue is that the simulator response-time is not equal to the physical response time of the hydraulics - so you can reprogram the software simulator to match your custom hardware; or you can modify your custom hardware to match the simulation. Nimur (talk) 18:22, 8 October 2009 (UTC)
I don't know why you don't want the software to control the platform. Microsoft's Flight Simulator can be used to control things like this I believe, at least that's how I understand how a system like yours I know about is controlled. I couldn't find the links to that system, they seem to have disappeared, but here are a couple of others to enthusiasts I found while looking [1] and [2]. There are a number of home brew systems around ranging from the simple to the downright amazing so you should be able to find others to talk to about your system. Dmcq (talk) 22:38, 8 October 2009 (UTC)
Sorry didn't understand, you do have it connected up properly. I guess what you mean by "Note this simulator is entirely active. There is no feedback from the simulator back into the cockpit to control motion." is that flight simulator just says where the platform should be but doesn't adjust the motion of the plane to cope with any delay problems in the hydraulics. Dmcq (talk) 22:48, 8 October 2009 (UTC)
What I should have done first is point to Microsoft Flight Simulator which lists some organizations which include people doing this sort of thing. The system I was thinking of has two very clever people who together have designed and built two quite different and very good simulators and getting help from people like them is the thing to do. Dmcq (talk) 11:10, 9 October 2009 (UTC)

First let me say that I used to design flight simulators for a living (at Rediffusion, Hughes aircraft, Link, L3) - so I actually know what I'm talking about here!

You will never get the right motion response by connecting the joystick/yoke to the hydraulics. It's an impossibility because the plane doesn't move only in response to the stick. To take an extreme example - if the plane is taxiing at 10mph and you wiggle the yoke, precisely nothing will happen in the real world - but as I understand it, your system will dutifully roll or pitch the cockpit! OK - you may say that you don't care about taxiing - but that's just the simplest example to explain here. You absolutely need to get into the flight dynamics software and read the body-relative accelerations and velocities of the aircraft.

Furthermore - the roll and pitch of the cockpit should emphatically NOT track the roll and pitch of the aircraft in the virtual world. You cannot possibly reproduce the true feel of flight - so you have to produce "cartoon motion" - so that the key cues that the pilot would feel are conveyed in at least some fashion in the motion.

When (for example) you are flying straight and level and you open the throttle or kick in the after-burners - the pilot will expect to be pushed back in his seat. This is amazingly easy to do! It just requires you to tilt the cockpit backwards to allow the real-world gravity to take the place of the acceleration of the real plane. Trust me - if you shut out the view of the outside world so all you can see is the inside of the cockpit and the graphics display - and tip the cockpit very gently backwards (10 or 20 degrees is plenty) while the graphics show you going faster - it's a total rush! You'll be blown away by how cool that feels! Alternatively - if you put the plane into a steep dive - it's pretty much in free-fall - so the pilot doesn't FEEL like the plane is pitched forwards at all - you aren't pushed forwards into your seatbelts when the plane dives - that feels totally wrong!! In that situation, the best you can do is to keep the cab dead flat and let the graphics convey the 'falling' impression. The LACK of motion input is what best conveys that floaty pit-of-stomach feeling because when the graphics show you falling but you aren't being pushed forwards, you realize that the plane is not slowing down but actually speeding up. In a properly balanced turn - the plane could easily be banked over at 45 degrees - yet the pilot will feel no horizontal forces the simulator cab emphatically shouldn't be rolled over 45 degrees! That would give the pilot the incorrect impression that he's rolled but not fact, experienced pilots will get rather extreme "simulator sickness" from that kind of incorrect cab motion.

I'm betting that you don't have enough motion on your hydraulics to roll the plane inverted or pitch it completely nose down. That's pretty much standard for hydraulic flight simulators - and the solution is to use the motion you DO have to hint to the user that the motion of the plane has changed.

It's almost true to say that you translate acceleration in the virtual world into position in the real world...constant rotational velocity or constant angular position in the virtual world has to be subtly and gradually 'washed out' so that the simulator slowly returns to the horizontal position. You also need to use your motion capability to do turbulance and other vibrations and such...that adds FAR more to the feeling of really flying than simply tipping the cab in response to joystick input.

The lag problem you're seeing probably means that your motion system is not sufficiently powerful for the loads you're giving it - but you have enough other problems that could be adding to that - calibrating the roll rate to the amount of joystick input would be really hard because the amount of stick input you need to produce some specific roll rate of the aircraft depends on the speed you're travelling (for example) - and I presume your stick-driven motion has no clue what the speed of the plane is.

So you're doomed to never having it match up even if you choose to accept the many limitations I've described above - you're simply beating your head against a brick wall - this is a problem you can't solve this way.

But with the best software imaginable, you need some pretty serious hydraulic pumps and fast proportional control valves to get the high rates of acceleration you need - and you need feedback because the hydraulic performance varies dramatically under load and depending on the hydraulic pressure you have. The last super-cheap, minimally useful 3-axis system I worked on could accelerate the ends of the hydraulic jacks at about a half-g under full load with a maximum displacement of about a meter. Because it was impossible to maintain that degree of flow from a sensible sized pump, we had a high pressure reservoir that the pump topped up during gentle flight - then, when you did something violent, the reservoir would provide the necessary "oomph". The software had to track the amount of high pressure oil remaining and 'tone down' the amount of motion it used - so if the pilot was doing violent aerobatics for long periods, the motion would gradually become less and less effective - but for "normal" uses, it was plenty good enough.

But there are any number of other possible causes for lag. I would also strongly suggest that you consider going to a THREE axis motion base - you really need the "Heave" (up/down) axis as well as roll and pitch. Heave gives you better ways to handle vibration than roll/pitch shake - and you can also drop the cab dramatically when you pitch over to really get that brief "negative g" feeling (even though it's only reducing the gravity the pilot's feeling by at most 50% - that's enough to give you the right feeling).

Bottom line is that until you're driving the motion from the flight dynamics software - you are totally doomed to failure.

SteveBaker (talk) 02:45, 11 October 2009 (UTC)

Unable to delete a folder in C:/Programe Files[edit]


I am using Vista (for my sins) and I am trying to delete a folder that is in Program Files. I have given myself full permissions but it still wont let me delete the folder any ideas. BigDunc 18:25, 8 October 2009 (UTC)

What's the error message? My bet is that a program is using it, still. Usually you can fix this by rebooting. At worst, reboot in safe mode. But make sure it's something you really don't need, if something is trying to still use it! --Mr.98 (talk) 18:28, 8 October 2009 (UTC)
The error is you need permissions to perform this action, I am the administrator and as I said I have changed the permissions but still no joy. Also it is not being used and I have rebooted before I posted just in case. BigDunc 18:32, 8 October 2009 (UTC)
Note that, in Windows, the directory separator character is "\", not "/". But unless you use a command-line utility, this should not matter. --Andreas Rejbrand (talk) 19:09, 8 October 2009 (UTC)

I have solved the problem, I found a piece of software here that does it for you. BigDunc 19:22, 8 October 2009 (UTC)

Windows Defender reports your ccollomb website as unsafe. Does anyone know why? Is it just Microsoft being over-cautious? Dbfirs 08:18, 11 October 2009 (UTC)
Because you can do lots of fun things with a utility that can force lots of files/directories to become unlocked. I've used Unlocker Assistant for a long time, their website is fine. Washii (talk) 02:44, 14 October 2009 (UTC)

Beginner C++ graphics examples[edit]

I'm looking for examples of what others have done for including graphics in beginner C++ courses. The problem is that often the students have either Windows or Mac machines. The servers at the university/school run some form of *nix. So, cross-platform graphics that are monstrously simple for the students becomes a problem. I've even considered having a separate, highly complex, graphics engine class that the students do nothing more than instantiate and start up with their classes providing the logic for whatever is running again, cross-platform simple graphics is an issue. -- kainaw 20:00, 8 October 2009 (UTC)

2D OpenGL is easy. --Andreas Rejbrand (talk) 20:15, 8 October 2009 (UTC)
Not the type of advice you're looking for, but the easiest solution is to standardize on a single platform. Since Unix machines are what all students are guaranteed to have access to, that seems like the normal decision. Comet Tuttle (talk) 20:20, 8 October 2009 (UTC)
Do you mean graphics like drawing on the screen, or like GUI toolkits? --Sean 20:26, 8 October 2009 (UTC)
SDLucid and SDLmm are both basic C++ wrappers over Simple Directmedia Layer, and should work without issue on all the platforms you discuss. I'm not aware of what people have used these, or SDL in general, in introductory programming courses (it's rather hard to google for that, it turns out); perhaps if you contact the maintainers of those two wrappers (or the SDL mailing list) someone may know of what use has been made of them in education. It'd be tempting to have them code a simple game (space invaders has lots of objects flying around, which makes an OO implementation seem like a sensible path), but you have the problem (and I think you'll have this with whatever toolkit you use) that you're shifting from the strightforward in-dostuff-out program structure to an event-driven paradigm, which might be a big cognitive jump for a brand new programmer. Alternatively you could skip the interactivity, and replace the screen/file output stuff they've been doing with an image or pdf generator library like libharu or GD. -- Finlay McWalterTalk 20:36, 8 October 2009 (UTC)
I have worked on a modified version of Turbo c++ graphics.h header file and created my own original version of "Paint" with most of the features + mouse interaction as well.
If you would like to see that,i've uploaded it to as a RAR archive which includes the code and the executable for the program.
As a student i realised this was the easiest graphics to understand and the easiest to use ,to produce some stunning results like my paint if you're creative enough.
Hope it helps.If you want the modified graphics.h header file for the mouse interaction functions ,don't hesitate to ask.
Oh PS: I'm a college freshmen and made this code in high school on my own with the internet as reference for learning the turbo c++ graphics commands,and i'm sure others would understand it as well. —Preceding unsigned comment added by (talk) 21:27, 8 October 2009 (UTC)
"Neon Helium Productions" has some nice beginner level OpenGL tutorials. APL (talk) 22:08, 8 October 2009 (UTC)
Thanks for the suggestions. Due to limitations of the systems at the University (no X on the programming machines), I cannot use OpenGL - which I would prefer to use. I've been googling and googling. I found some simple examples in which the instructor wrote most of the graphics in curses and the students just added the logic. I believe that curses will run both on Windows and Linux/BSD without a problem. I'm going to experiment tomorrow. -- kainaw 22:51, 8 October 2009 (UTC)
I think you should teach them using DirectX, which will be more useful than any alternative upon graduation. Comet Tuttle (talk) 16:51, 9 October 2009 (UTC)
Or graphics fundamentals, which will be more useful than any alternative long after graduation. --Sean 19:04, 10 October 2009 (UTC)
I'm teaching "what is a function" now and nearing discussion of arrays. I don't plan to teach DirectX or any other specific graphics programming right now. I was looking for assignments where the instructor uses graphics and the students write non-graphics code. The point is to make the display a bit more interesting that just console in/out. -- kainaw 01:35, 11 October 2009 (UTC)
Kainaw: You're saying the Windows machines don't have X? Doesn't matter - OpenGL will run just fine on an X-less Windows system. If you're saying that these are Linux machines without X then you're doomed. Without X, just about no graphics will work under Linux. There used to be 'framebuffer' graphics - but they sucked really badly and probably don't work anymore. SteveBaker (talk) 02:01, 11 October 2009 (UTC)
OpenGL is almost entirely cross-platform portable. The problem is that the mechanisms to open a window, read a keystroke, track the mouse, etc - are not. Most simple applications - and almost all example programs in OpenGL manuals use a library called "GLUT" (The GL Utility Toolkit) to hide those differences. GLUT can deal with the underlying horrors of these things with just a couple of function calls. It is entirely possible to write a program using GLUT and OpenGL that runs 100% identically under Windows, Mac and Linux. You might like to check out the "freeglut" library - which is a fully OpenSourced plug-compatible version of GLUT - which I happen to be the project owner of. DirectX is the only serious rival to OpenGL - but it runs only on Windows machines - and (in a somewhat messed up form) on the Xbox and Xbox360. For every other platform (including the Mac, Linux, Wii, iPhone, Android phone and (soon) for 3D graphics in a browser window) you need OpenGL or OpenGL-ES (which is a cut-down dialect used in 'embedded systems' like phones). The Playstation-3 supports a kinda-sorta OpenGL dialect - but most games programmers dump the graphics API and program directly on the 'bare metal'.
Sure - there is a place for DirectX - but with many MANY graphics applications showing up on phones - it's not as cut-and-dried as it once was. Phone manufacturers can't affort to pay the Microsoft tax - so DirectX is useless for phones. OpenGL-ES was specifically designed to be suitable for those teeny-tiny platforms - and is rapidly becoming the main dialect of OpenGL used in other places.
With the announcement that every browser on the planet will soon support OpenGL-ES (except, inevitably, Internet Explorer...unless you get the Chrome plugin) - you can even write full-scale OpenGL-ES applications with shaders and all of that cool stuff in JavaScript that'll run in a browser window! That is so amazingly, astoundingly COOL - and DirectX will never be able to do that because of it's appalling lack of portability.
I've been using OpenGL since the very beginning of 3D graphics - and when I recently needed to switch to DirectX (because I write computer games for a living and needed to be able to write for the Xbox-360), it took me about a week to get switched over. With modern graphics being 99.9% a matter of setting up shaders and textures, then splatting a big pile of triangles at the GPU, 99% of the 'stuff' in both of those graphics API's is utterly obsolete. You need to learn the efficient ways to arrange your big piles of triangles - then you need to learn a shader programming language. If you learn 'Cg' - you can use the identical shader language under Windows, Linux and Mac. If you learn HLSL - then you're kinda stuck with Windows. If you learn GLSL, then you're stuck with OpenGL and you'll be OK on almost every platform that runs OpenGL. Fortunately, Cg, HLSL and GLSL are very similar indeed.
SteveBaker (talk) 01:58, 11 October 2009 (UTC)
I find it a bit odd that when I say "graphics", I mean "anything more than console-based text." However, it appears that most people here read "graphics" and think "3D graphics engines." All I want to do is add a little color and perhaps a little cursor control to these student's programming assignments. For example, the next assignment is "Liar's Dice". It would be nice if I could show something that looks like dice instead of just numbers. But, in a console-only environment, it appears to be more trouble than it is worth. -- kainaw 02:38, 12 October 2009 (UTC)
I understand your meaning - but that doesn't change the answer. Teaching the ad-hoc graphics interfaces that things like Java provide will be a dead-end for your students. They'll get to some point - want to do something that that interface can't handle - and be faced with starting again from scratch. Using something like GLUT and OpenGL (or DirectX if you really have to) will give them the ability to progress from the simple things you want, gradually up to full scale 3D (or whatever). Drawing boxes in solid colors isn't hard in API's like OpenGL and DirectX. SteveBaker (talk) 03:26, 12 October 2009 (UTC)

Issues with new HP printer[edit]

I work in a small office, and our (really) old HP InkJet finally died. We've purchased a new A800-something, are having trouble with it, and HP tech support has been worthless so far. Perhaps some among you have seen this problem and can offer a solution.

CONFIGURATION: We have two WinXP boxes -- "PC1" and "PC2", say -- and two printers. The Laser (B&W) printer is connected to PC2 via USB, and the new color printer is connected to PC1 in the same way. Each of us can print on either printer, as each is shared through the usual Windows mechanism.

There is a building-wide "intranet", that each (of about 30) PCs plug into. Our two PCs are not directly wired to each other, nor do we have a router of our own. In other words, we have a perfectly standard small-office configuration.

THE PROBLEM: Documents printed from PC2 to the A800 print their CONTENT correctly, but do not always print in the proper CONFIGURATION. Examples, sometimes the document will print duplexed (even when told not to), or tumbled (flipped up rather than L-to-R), or 2-up on a page. Each individual page's CONTENT is correct -- proving there is no connectivity problem -- but the configuration or metadata or properties or whateveryoucallit doesn't make it or is ignored.

THE ISSUE: HP support insists that the ONLY way to share two printers is to purchase a router, and install a Lan-on-a-lan (as I understand it). I can't believe this is really the case, but I suppose anything's possible -- perhaps Windows Printer Sharing caused HP more problems than it was worth or something.

N.B. A previous poster's claim that "all of his HP problems were solved by buying a Dell box" is not an option for us, so please don't suggest that.

Thanks in advance, --DaHorsesMouth (talk) 21:15, 8 October 2009 (UTC)

One idea: MS Office programs (pretty much uniquely) store some printer settings (the printer's own page prefs) inside the document, and those changes apply when someone else prints the document. This has weird effects like person1 likes to print on colour, person2 in black, but if person1 edits the document, sets it to colour, prints it, saves it, then hands the document to person2 (on say a network or a usb stick), and person2 prints it, it'll come out in colour. Perhaps in your case, the problem is that person1 normally prints on one printer, person2 on the other, and the document is ending up with the settings for one printer embedded in it (which is ignored by the other printer). While this is sometimes helpful behaviour on Office's part (it allows you to do stuff like page1-on-letterhead, subsequent pages on regular paper, and the document itself remembers this printer-specific setting) it can do weird things when the printers aren't the same (and I don't know how to turn this feature off). As some printer properties are copied into the document, and some aren't, this can seem like a perplexing issue. Second idea: when you install a windows-networked printer, it offers to get the driver from the host machine for you; if you did this, try instead downloading and installing the driver manually (rather than getting it from the printer host); and in general make sure everyone is running the latest (and ideally the same) version of the printer driver. -- Finlay McWalterTalk 21:46, 8 October 2009 (UTC)
To see whether Office is the culprit, install CutePDF Writer, which is a free PDF creator that acts like a printer; and also install Acrobat Reader. Using PC2, first print to the CutePDF "printer"; it will ask you what filename to save the PDF file as; save it accordingly; then open and print that PDF file with Acrobat Reader. Comet Tuttle (talk) 22:59, 8 October 2009 (UTC)
Thought I'd mentioned everything that could possibly be of interest, but I was mistaken! In this case, we are printing PDF files from within Acrobat Reader.
It's probably also worth mentioning that I always check/reset printer settings via the Properties dialog -- it's just that sometimes those settings are ignored.
Any other suggestions? I'm willing to try just about anything that has an outside chance of working. (Terminating and restarting Acrobat is such a solution; I'd like to avoid that as the "production workaround" if possible.) --DaHorsesMouth (talk) 01:30, 9 October 2009 (UTC)
Have you set the Printing Preferences the way you want them in Control Panel? That would be my first step. My second would be to set the preferences the same on the machine that is sharing the printer - it may be that some documents inherit those by mistake. The other thing just to be aware of (though I think this doesn't apply to you since you're only using one commercial piece of software) is that some software ignores what the user asks for in terms of printer preferences and prints the document how it wants to. At the Small Office where I volunteer, we have an application that always prints to the default tray, no matter where you tell it to print. --Phil Holmes (talk) 13:35, 9 October 2009 (UTC)


I can't seem to get my ATI 4570 set up on ubuntu 9.04. Any/all help is appreciated. P.S. does anyone have invites to Google Wave? —Preceding unsigned comment added by (talk) 21:19, 8 October 2009 (UTC)

Are you using the driver that installs, or the fglrx proprietary driver? If using the former, try the latter (you should be getting an offer to install the proprietary driver, if ubuntu has detected it properly. Unfortunately, as the fglrx article notes, even ATI's own driver has been very poor (orders of magnitude slower than the Windows equivalent for the same card); I don't know the current status (the fglrx article's references are mostly rather old). I confess that the last time I tried to use Ubuntu on a Radeon machine I gave up and bought the cheapest nVidia card the shop had; nVidia's Linux driver is very good indeed. -- Finlay McWalterTalk 21:31, 8 October 2009 (UTC) is relevant reading. -- (talk) 21:43, 8 October 2009 (UTC)

Using Foxit Reader in Google Chrome[edit]

Hi. I was wondering if it is possible to open Foxit Reader in Google Chrome when opening PDF files on the web. Right now, PDF files are opening in Adobe Reader by default in Chrome but I can't find any setting in Google Chrome to open PDF files using Foxit Reader rather than Adobe Reader. I want to do that because I hate using Adobe Reader which is very slow and has become very user-unfriendly. This may sound funny but I read somewhere on the web that Larry Page had the same problem, lol. (talk) 21:26, 8 October 2009 (UTC)

Chrome just open files with using Windows's default program for that kind of file. Change the windows default (which you do by right-clicking a PDF-file, selecting "Open With", then "Choose program", select Foxit Reader, and make sure that the box is checked that says "Always use the selected program to open this kind of file") and it should work fine. (talk) 01:12, 11 October 2009 (UTC)

Sort files into Folders based on creation date[edit]


Hi All,

This is on a CentOS system running Asterisk. We seem to have accumulated so many recordings that I am having trouble compacting and moving them all (ie 'mv * someDir' and even 'mv *part-of-file-name(extension)* someDir' fails with too many arguments).

I was thinking the way to go would be to loop through the files based on creation date (in the filename, but maybe better if uses the filesystem's records or something), but don't know where to start. I think know what I want to do but dunno how to write it in shell script (and there's prolly more elegant algorithms out there):

(file format is usually xxxx-(date in yyyymmdd)-xxxx-xxxx.wav)

1.) get a list of files in the folder
2.) get the date of the oldest, in yyyymmdd format set that as '$date'
--- loop ---
3.) create the folder '$date' if does not exist (I think is supposed to be like if [-d yyyymmdd] ?)
4.) issue mv *-$date-* to $date/; get next date
--- /loop ---
5.) done

Thanks in advance for any help! PrinzPH (talk) 22:46, 8 October 2009 (UTC)

Test it first, but this should do it:
ls | perl -MDate::Format -lne '$d=time2str "%Y%m%d", (stat)[9]; mkdir $d; rename $_, "$d/$_"'
--Sean 00:46, 9 October 2009 (UTC)

Worked perfectly Sean! Thanks! PrinzPH (talk) 01:42, 9 October 2009 (UTC)

Automatic web page/html generator[edit]

I want to create an FAQ web page in which normally only the questions are visible, but when you click on a question, it expands and shows the answer with it. Clicking on a new question expands the answer for the new question and collapses the previous one. Is there any online html generator that can do it for me? Thanks. ReluctantPhilosopher (talk) 23:13, 8 October 2009 (UTC)

What are you editing the page with? It's not hard to do with Javascript/CSS, but if you're not editing the page by hand (e.g. in Notepad), then us posting a bunch of code is not going to be super helpful. --Mr.98 (talk) 00:36, 9 October 2009 (UTC)
I found the code online. Now the only hitch is actual coding. Can you suggest a good free html editor? ReluctantPhilosopher (talk) 01:41, 9 October 2009 (UTC)
Aptana is awesome! It doesn't have any wysiwyg (it does allow previews though), but the other features more than make up for it (has full javascript support, built in php testing deamon, as well as support for various js libraries like mootools, prototype -- havent used those features yet but i plan to). HTH PrinzPH (talk) 01:47, 9 October 2009 (UTC)
Thanks, but the webpage isn't loading. Anyway I found a very good free WYSIWYG editor that has greatly accelerated my work :] ReluctantPhilosopher (talk) 12:59, 10 October 2009 (UTC)

WHOIS queries on an IP[edit]

What does "allocated PA" mean in the context of a WHOIS query? Is that the same as "direct allocation" or is it something different? SpinningSpark 23:15, 8 October 2009 (UTC)

  • PA means "Provider Aggregatable", meaning that this particular range is a subset of a larger block that the provider owns. They issue the smaller blocks, but advertise a single larger (aggregated) network out to the rest of the world. Keeps routing tables small which is always nice. (The other one you see a lot in Whois is PI: "Provider Independent" which usually means the company owns that IP range rather than the provider, so it requires its own routing table entry). ArakunemTalk 00:25, 10 October 2009 (UTC)
    • And Allocated of course means that the IP range being queried has in fact been issued to a subscriber as opposed to being unused. ArakunemTalk 00:30, 10 October 2009 (UTC)
      • Thanks for the answer, people so rarely thank their answerers here, questioners - please be more grateful. SpinningSpark 11:16, 10 October 2009 (UTC)

Direct X 10 for XP[edit]

I have just installed unofficial version direct x 10 in XP 32 bit OS. Both "dxdiag" (from "RUN" option) and PC Wizard is showing Direct X version is 10.0. But whenever I open Realtek HD Sound Effect Manager, it shows Direct X 9.0. Is there any problem?

Why this is happening?

I am using XFX 750i SLI Mobo and XFX Geforce 9800 GT 512 MB. Thanks-- (talk) 23:23, 8 October 2009 (UTC)

I'd guess the app is showing what version of DirectX it was compiled against. -- (talk) 00:56, 9 October 2009 (UTC)
Adding to the above, the sound card drivers probably don't know how to use DirectX 10 (since as you know it's not officially supported in XP). Likewise I would think the same thing would probably happen with the display drivers as the XP drivers likely don't support DirectX 10. So although you've got it "installed", if the hardware drivers don't support it then it's really not doing much. ZX81 talk 02:59, 9 October 2009 (UTC)
  • Is reinstalling Realtek HD Sound Effect Manager will solve that issue? I have some images of Direct X 10 where the uploader of this software was successful to install and use it in Realtek HD Sound Effect Manager, His mobo is Asus.-- (talk) 08:26, 9 October 2009 (UTC)