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September 14

FRACTALS

210.212.239.181 (talk) 04:55, 14 September 2009 (UTC)harshagg

I am a begginer and know only few things on fractals.How can i know about them including how to programme.I tried on wiki itself but i am unable to understand that.

I assume that you have seen our article on fractal software. If you are a competent mathematician, artist and programmer, I suppose you could "re-invent the wheel". Dbfirs 11:58, 14 September 2009 (UTC)

To get you started, the "Escape time algorithm" is probably the easiest to code. Dbfirs 06:24, 15 September 2009 (UTC)

Is a really old Webroot Spy Sweeper of any use?

i still the above and Trend Micro Anti-Virus on my Windows XP machine, though the subscriptions for each ended last summer. (Can't afford to purchase updates) I'm using free AVG and also McAfee from AOL, which update regularly, and seem to be getting pretty good results. McAfee seems able to catch any programt hat want to get into my system. I surf the Web little, except for half a dozen familiar places, and almost never watch anything on YouTube, though I will very rarely. Is my spyware protection too redundant?209.244.187.155 (talk) 15:48, 14 September 2009 (UTC)

It is usually a bad idea to have more than one antivirus program installed. My advice is to uninstall all of the antivirus programs that are no longer valid as well as AVG (it has a pretty poor detection rate). McAfee isn't bad, but there are several good and free anti-virus programs out there for you to consider if McAfee runs out. I know Microsoft has a new program coming out soon that is getting good reviews.Caltsar (talk) 17:36, 14 September 2009 (UTC)

Printing Hotmail emails: tiny text, no word wrapping

When I want to print a Hotmail email a bare window appears with tiny text and no word wrapping. How can I increase the text size and get the text to wrap please? 78.146.163.118 (talk) 16:48, 14 September 2009 (UTC)

What browser and operating system are you using? — QuantumEleven 18:48, 14 September 2009 (UTC)

Internet Explorer 8, Windows XP Sp3. 89.243.184.30 (talk) 19:41, 14 September 2009 (UTC)

Single character key doesn't work

Hello! I have a really strange PC problem, for which I have no idea how to start diagnosing it. My closing-parenthese symbol (shift-0) doesn't work. 0 works fine, as do all the other capital keys (shift-someotherkey), so it's not a hardware problem with either the 0 key or the shift key. I have checked, my keyboard layout is set correctly (English-UK). The behaviour is identical in all programs and doesn't go away after a reboot. Does anyone have any suggestions on how I might narrow down the culprit? Thanks in advance! — QuantumEleven 18:43, 14 September 2009 (UTC)

Do you have a different keyboard you could try? Perhaps you could borrow a friend's keyboard to see if the problem is on the keyboard or on your computer (either hardware or the OS). That would help to diagnose the problem. Caltsar (talk) 19:12, 14 September 2009 (UTC)

If you are using windows, go to start, run, and type charmap.Accdude92 (talk) (sign) 19:26, 14 September 2009 (UTC)

Perhaps a background program is "trapping" the keystroke. For example, I often have XNote Stopwatch running in the background while I'm working. Although it's a great program, it has one flaw - if you happen to press one of its keys (S, N, or R) while the stopwatch is running, the action assigned to those keys happens whether the stopwatch window is active or not. It was quite annoying, until I found out how to disable keyboard shortcuts. If you use Windows, you might want to check if this is the case. If all else fails, you can always try reinstalling the driver (KB258826, step 3). Basically it's going into Device Manager (devmgmt.msc), uninstalling the keyboard, rebooting, then letting Windows automatically detect and reinstall. Xenon54 / talk / 19:43, 14 September 2009 (UTC)

Caltsar is correct; it is probably a hardware problem with that one key on your keyboard, and the way to diagnose this is to try a different keyboard for a few seconds. Comet Tuttle (talk) 21:12, 14 September 2009 (UTC)

Or as Xenon54 suggested, it might be a software problem trapping the Shift+0 combination. You could try the keyboard at another computer and see if works or not. If possible, both tests (try a new keyboard at the computer with the problem; try the keyboard with the problem at another computer) should help you narrow the problem down and decide how to further investigate. --Bavi H (talk) 23:48, 14 September 2009 (UTC)

Cursor turns into spinning circle on top of Geejo's name

I'm not sure whether this goes on the village pump or not. Here [1] I was moving the cursor across Geejo's name and it turned into a spinning circle. I was dealing with a slow web site on another screen, but the problem continued even after that site came up there--though that site's URL was on the top of the screen where I was on Wikipedia!Vchimpanzee · talk · contributions · 20:08, 14 September 2009 (UTC)

It does that on my computer too. (Ubuntu 9.04, Firefox 3.5.2) GeeJo is still around, so it might be interesting to ask him how and why it does that (if he did it deliberately). Xenon54 / talk / 20:12, 14 September 2009 (UTC)

He has CSS style that read "cursor: wait;" which does that (on modern browsers). 87.113.10.108 (talk) 20:23, 14 September 2009 (UTC)

I have Explorer 8 and Vista. I can never remember where all this information is to say what my computer is, but that's probably enough in these cases.

I've asked this person to respond.Vchimpanzee · talk · contributions · 20:43, 14 September 2009 (UTC)

Surely his CSS style has nothing to do with the symptoms you see on other web pages. I recommend getting more RAM for the computer, and you should close Adobe's PDF reader whenever possible. I regularly see annoying slowdowns when PDF files are open (whether in the reader or in the browser). Comet Tuttle (talk) 00:00, 15 September 2009 (UTC)

Yes,I had that effect (changing cursor style while hovering over my name) on my signature for a while for a laugh. The effect is only a mouseover, it shouldn't change how the cursor works when it's not pointed at the word GeeJo on some of my old comments. It wasn't long before I decided that the effect was fairly annoying, and I switched to my current signature. I'm not planning on going back through every archived talk page to retrofit my old comments, though. GeeJo ^(t)⁄_(c) • 07:05, 15 September 2009 (UTC)

Java References

Basically, I am trying to program something like this...

private Object[] myArray;

public E get(int i)
{
return((E) myArray[i]);
}

public T next(int i)
{
return((T) get(i));
}

...and I expect next(int i) to return a reference to the original Object, but it doesn't. It just gives me a copy. Is there anyway that I can make it pass me a reference? Furthermore, I am perplexed why this is happening in the first place. I am pretty sure I have passed references to class objects before. Does the array or casts have something to do with it? By the way, this isn't a homework assignment or anything; I'm just trying to familiarize myself with the language. 199.111.182.231 (talk) 23:53, 14 September 2009 (UTC)

Hmm... I think I may have answered my own question. In my implementation, I was using Integers, which do not have the mutator methods necessary to adjust the original value. 199.111.182.231 (talk) 00:08, 15 September 2009 (UTC)

September 15

Scalability of two-tier versus three-tier architectures

I'd be grateful for insight into the relative merits of a two-tier versus a three-tier architecture, from the point of view of the scalability of an IT application. Why might one approach be superior to the other? Consider, for instance, an Oracle Application Express (two-tier) versus J2EE or .Net three-tier architectures, for an application which might today serve 1,000 concurrent users, but next year 2,000 or 10,000.

I can (at least intuitively) understand the benefits of logical separation of elements of the application, per Multitier architecture, both in terms of modularisation of code and in the ability to provide distinct platforms for each of the tiers. And so I can see that there is some benefit, from the scalability perspective, in being able to ramp up the hardware provided to a distinct layer, based on an understanding of the pinch points in the system. But as a general proposition, can one approach be thought to be better than the other in its ability to scale, measured, I guess, in terms of cost of hardware deployed?

And - whilst we're on the subject - would I be right or wrong in postulating that a three-tier architecture will tend to need more tin than a two-tier architecture, all other things being equal?

I assure you this is not a homework question: I'm struggling to get an insight into what are for me rather abstract concepts, and I have an obscure interest which needs to be satisfied. thanks. --62.49.21.172 (talk) 00:23, 15 September 2009 (UTC)

It's really going to vary based on the application and the use-case. The real benefits of a three-tiered architecture come more from a project-management and logistics standpoint, rather than a purely hardware/software consideration. By separating the different predicted bottlenecks, it's possible to assign teams to work on independently optimizing those cases. However, the actual bottleneck in a given application is going to depend on the precise interplay of each transaction with each tier of the software architecture. And, it's possible to measure the cost per unit of hardware in each sub-area, which can be evaluated by the budgeting people as a tradeoff against end-user experience and overall system performance. As far as the "most tin", it's again going to be a case-by-case situation; but the system which uses the least number of nodes is also going to be the most tightly-knit, hardest to maintain, and least redundant system. Modularity is useful in these deployed platforms for maintainability, more than performance; in truth, if it were possible, the entire system could be most efficient as a single layer application. (The challenges of scaling then strictly rely on whether a single node can clone all the required data, and whether data hazards result from this). But, the single standalone-node is the penultimate in pure parallelization - every single unit of the deployed system is a miniature, exact replica of the rest of the system. "Scaling" simply means duplicating these units. Upgrading or modifying, however, becomes a near-impossible task, propagating changes dynamically to n independent nodes. Nimur (talk) 02:21, 15 September 2009 (UTC)

Installing Pygame on Ubuntu Hardy Heron

Hi,

I've been given a laptop with a fresh install of Ubuntu (8.04, Hardy Heron) I'm a total linux newbie, but have spent a few days getting a feel for Ubuntu (and liking it a lot, I might add), and wanted to try doing some game dev on it. Python + pygame seems like a good way to go, and the system came with Python 2.5.2 installed. I've been reading through the docs on the pygame site on how to install it, and mostly it seems to come down to doing a "sudo apt-get install python-pygame", but whenever I do that I just get 'package not found'

As I said, I'm very new to the whole Linux thing, so I might be looking in the wrong repositories or something (I don't really know how to change that yet, but I get that you can) I tried using Ubuntu's add/remove software manager, and searching the 'all apps' category, but nothing came up for pygame.

Any help would be appreciated!

--67.171.37.222 (talk) 03:09, 15 September 2009 (UTC)

You're probably not going to like this answer, but one friend of mine tried getting started with Pygame, struggled for a day, switched to XNA Game Studio with Windows, and was immediately far happier. Tempshill (talk) 04:35, 15 September 2009 (UTC)

Is this a new install? The package is in fact called python-pygame (at least in 9.04) so the problem probably that you don't have the repository (universe) enabled. Open System/Admin/Software Sources and tick the first 4 checkboxes in the dialog, then press close and then reload. It should find the python-pygame package now. BTW, Synaptics (System/Admin) is a lot better at searching for packages than Add/Remove software. --antilived^{T | C | G} 06:42, 15 September 2009 (UTC)

You, sir or madam, as the case may be, are a genius. Thank you! Worked like a charm, and pointed me to a great package manager I wasn't even aware of --67.171.37.222 (talk) 07:05, 15 September 2009 (UTC)

Escrow for virtual items either items from games or computer code?

I have been searching for days and google only turns up garbage. Does anyone know or know how to find escrow systems that would be good for selling virtual items over the internet such as item from games or source code for freelance coding? Normal escrow sites only deal with physical items or domain names and have $25 minimum escrow fees, and then source code escrow sites charge about $1000 minimum fees and are designed for only working with large companies and enslaving them with long-term contracts. Are you ready for IPv6? (talk) 05:18, 15 September 2009 (UTC)

Converting between SVY21 and WGS84 Coordination system

hello. Im on this project currently. To convert between the 2 coordinate system (SVY21 and WGS84) i found quite a bit of information. But just cant figure out how does SVY21 work. Any kind soul can help me with that? your aid will be greatly appreciated. —Preceding unsigned comment added by Razorsaber (talk • contribs) 05:56, 15 September 2009 (UTC)

SVY21 is a transverse Mercator projection. Our article on the subject may be of help. decltype (talk) 06:03, 15 September 2009 (UTC)

SVY21 is a geodetic datum (EPSG 6757), a geographic coordinate system (EPSG 4757) and SVY21 / Singapore TM (EPSG 3414) is the projected coordinate system decltype mentioned. The EPSG registry seems to be down at the moment, but here are the well-known text representations for the geographic and projected systems. What is it that you can't figure out? If you'd just like an introduction to coordinate systems, i'd recommend EPSG's Geodetic awareness guidance note.—eric 18:35, 15 September 2009 (UTC)

Oh, sorry for giving an inaccurate answer. decltype (talk) 19:25, 15 September 2009 (UTC)

db2 and sql

is there any difference between db2 and sql?if its there then please help me.... —Preceding unsigned comment added by Kc28kc (talk • contribs) 10:35, 15 September 2009 (UTC)

IBM DB2 is a Relational DataBase Management System (DBMS, a software package to handle databases) whereas SQL is a query language (a set of comands for extracting and manipulating data through a DBMS, unless you are talking about the Microsoft SQL Server - which is another DBMS). I know that's not very helpful but I don't know much more --ReluctantPhilosopher (talk) 13:28, 15 September 2009 (UTC)

"SQL was developed at IBM by Andrew Richardson, Donald C. Messerly and Raymond F. Boyce in the early 1970s" from Structured Query Language. --Jc3s5h (talk) 17:03, 15 September 2009 (UTC)

Do you mean mysql? Rbmj (talk) 19:07, 15 September 2009 (UTC)

The history and architecture of the ARM microprocessors

I would like learn about the ARM processors, how and when they began, including the architecture of the processor. A lengthy and detailed response will do. —Preceding unsigned comment added by 196.2.2.228 (talk) 15:34, 15 September 2009 (UTC)

Have you read ARM Holdings and ARM architecture? You can then start on some of thge people mentioned like Furber and Wilson. Dmcq (talk)

History glitch in Internet Explorer 8?

I have the problem at home, and apparently it's here at the library too.

I figure this computer must have the new version because the URL is gray except "wikipedia.org" is black.

I use the back button a lot but it seems that history repeats itself. Instead of going back, the back button seems to go forward before going back. I'm pretty sure I'm not clicking on the forward button by mistake.Vchimpanzee · talk · contributions · 17:53, 15 September 2009 (UTC)

Does this happen with one particular URL, or every URL you have seen? Do you end up, in fact, at the same page you started with, or do you end up one page back in the history? Comet Tuttle (talk) 21:58, 15 September 2009 (UTC)

It doesn't happen that often. I did get stuck in an endless loop one day with just two pages.Vchimpanzee · talk · contributions · 18:12, 17 September 2009 (UTC)

I'm in an endless loop right now. And I see the Forward button "flashing". That doesn't happen.

I clicked on "Inbox" in my email. That stopped the loop.Vchimpanzee · talk · contributions · 20:06, 17 September 2009 (UTC)

It happened again. This time I got an error message because I had deleted the email I was going "back" to. It should have just gone back to where I was before I looked at the email I deleted.Vchimpanzee · talk · contributions · 20:11, 17 September 2009 (UTC)

I ended up in a loop. I don't know how. It wasn't email. It was Wikipedia.Vchimpanzee · talk · contributions · 18:04, 28 September 2009 (UTC)

JAVA repaint problem

This JAVA program works fine, except that the repaint() method doesn't work. Why is this and how can I fix it?

Massive amount of code collapsed. Tim Song (talk) 19:31, 15 September 2009 (UTC)

package towerdefense; import java.io.*; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class TowerDefense extends JFrame implements ActionListener { public static void main(String[] args) { new TowerDefense(); } JFrame game; JPanel panel; Image dbImage; Graphics dbg; Timer timer = new Timer(1, this); JFileChooser openDialog; int boardWidth; int boardHeight; int tileSize; int pathLength; int[][] coordinates; int[][] directions; boolean[][] board; int maxHealth = 20; int health = maxHealth; Enemy enemy; public TowerDefense() { openDialog = new JFileChooser(); openDialog.addChoosableFileFilter(new MapFilter()); try { int returnVal = openDialog.showOpenDialog(null); if (returnVal == JFileChooser.APPROVE_OPTION) { String filename = openDialog.getSelectedFile().toString(); FileReader reader = new FileReader(filename); String text = ""; boolean keepGoing = true; while (keepGoing) { int character = reader.read(); if (character == -1) { keepGoing = false; } else { text += (char) character; } } String[] array = text.split("x"); String[] coordinateArray = array[2].split(";"); pathLength = coordinateArray.length; coordinates = new int[pathLength][2]; directions = new int[pathLength][2]; for (int i = 0; i < pathLength; i++) { coordinates[i][0] = Integer.parseInt(coordinateArray[i].split(",")[0]); coordinates[i][1] = Integer.parseInt(coordinateArray[i].split(",")[1]); directions[i][0] = Integer.parseInt(coordinateArray[i].split(",")[2]); directions[i][1] = Integer.parseInt(coordinateArray[i].split(",")[3]); } boardWidth = Integer.parseInt(array[0]); boardHeight = Integer.parseInt(array[1]); tileSize = Math.min(getToolkit().getScreenSize().height / boardHeight, (getToolkit().getScreenSize().width - 300) / boardWidth); board = new boolean[boardWidth][boardHeight]; for (int i = 0; i < boardWidth; i++) { for (int j = 0; j < boardHeight; j++) { board[i][j] = false; } } for (int i = 0; i < pathLength; i++) { board[coordinates[i][0]][coordinates[i][1]] = true; } enemy = new Enemy(coordinates[0][0], coordinates[0][1], 100, 0, directions, -tileSize / 2, 0, tileSize / 2); } } catch (Exception e) { showErrorMessage(e); } game = new JFrame("Tower Defense"); panel = new JPanel(); game.setPreferredSize(new Dimension(getToolkit().getScreenSize().width, getToolkit().getScreenSize().height)); game.add(panel); game.setExtendedState(MAXIMIZED_BOTH); game.setDefaultCloseOperation(EXIT_ON_CLOSE); game.setVisible(true); game.add(new JCanvas()); timer.start(); } public void actionPerformed(ActionEvent e) { if(enemy.move()) { health--; } repaint(); } public void showErrorMessage(Exception e) { JOptionPane.showMessageDialog(null, "An error has occurred.\n\nDescription:\n" + e.toString(), "Error!", JOptionPane.ERROR_MESSAGE); System.exit(0); } class JCanvas extends Canvas { public void paint(Graphics g) { for (int i = 0; i < boardWidth; i++) { for (int j = 0; j < boardHeight; j++) { if (board[i][j]) { g.setColor(Color.orange); } else { g.setColor(Color.black); } g.fillRect(i * tileSize, j * tileSize, tileSize, tileSize); } } g.setColor(Color.blue); if (enemy.isAlive) { g.fillOval(enemy.x * tileSize + enemy.xOffset + tileSize / 2, enemy.y * tileSize + enemy.yOffset + tileSize / 2, tileSize / 4, tileSize / 4); } g.setColor(Color.black); g.setFont(new Font("Courier", Font.BOLD, 50)); g.drawString("HP", getToolkit().getScreenSize().width - 300, 50); if (health > maxHealth / 2) { g.setColor(Color.green); } else if (health > maxHealth / 4) { g.setColor(Color.yellow); } else { g.setColor(Color.red); } g.fillRect(getToolkit().getScreenSize().width - 240, 0, health * 240 / maxHealth, 50); if (health > maxHealth / 2) { g.setColor(Color.magenta); } else if (health > maxHealth / 4) { g.setColor(Color.blue); } else { g.setColor(Color.cyan); } g.setFont(new Font("Helvetica", Font.PLAIN, 25)); g.drawString(health + "/" + maxHealth, getToolkit().getScreenSize().width - 240, 50); } } }

--204.184.214.2 (talk) 19:01, 15 September 2009 (UTC)

While you're waiting, you might like to take a peek at Wikipedia:Reference desk/How to ask a software question. --Sean 20:34, 15 September 2009 (UTC)

Absolutely - I agree with Sean's comment above. Fortunately, I managed to track down your bug (I think). First of all, you extend JFrame, but you also initialize a new JFrame, "game". Instead, your class should call the super() method, and you do not need a "game" instance variable. (See how to use super() to extend classes). Also, you add your JCanvas to the JFrame; but (surprisingly) this is not correct. In Java Swing, (unlike AWT), always add to contentpanes - not to JFrames. (See why). Read about Swing top-level containers here - in your code, you want to add to the JFrame "game" (or the JPanel "panel")'s content pane. I've also boiled down some code for you to see how to do this properly. Nimur (talk) 23:34, 15 September 2009 (UTC)

Nimur's example of "proper" JFrame and ContentPane usage.

package test; import java.awt.Canvas; import java.awt.Color; import java.awt.Container; import java.awt.Graphics; import javax.swing.JFrame; public class TowerDefense extends JFrame { public static void main(String[] args) { new TowerDefense(); } public TowerDefense() { super("Window Title"); this.setSize(640,480); Container c = this.getContentPane(); c.add(new JCanvas()); this.repaint(); this.setVisible(true); } class JCanvas extends Canvas { public void paint(Graphics g) { g.setColor(Color.BLACK); g.drawRect(50,50,50,50); } } }

.

Hopefully you will understand this simple code, and see the changes you need to make to your own class. Primarily, you want to use the Container object, obtained by the getContentPane() method of the JFrame (or JPanel) that you plan to hold the drawable Canvas area. Watch out; you're secondary issue is that you're mixing up a JFrame instance called "game" with a TowerDefense object ("this"), which is also a JFrame. Nimur (talk) 23:33, 15 September 2009 (UTC)

(ec)If i remember correctly (and that pretty iffy for Java) JFrame.repaint() does not actually repaint its contents. You do something like frame.getContentPane().repaint() or declare a member variable for your canvas object and use canvas.repaint().—eric 23:36, 15 September 2009 (UTC)

The above depends on whether the JFrame's child(ren) are lightweight or heavyweight objects. There's more details here: Mixing Heavy and Light Components. Repaint() on the JFrame should cascade to the OP's JFrame content pane and its child JCanvas object, in this case - if the JCanvas resides on the Content Pane (but if the JCanvas resides on the JFrame, all bets are off). Nimur (talk) 23:41, 15 September 2009 (UTC)

Here's my code after making the changes you suggested (with all the irrelevant parts removed). It still doesn't work. What else should I change? --204.184.214.2 (talk) 18:35, 17 September 2009 (UTC)

Code collapsed. NorwegianBlue talk 20:53, 17 September 2009 (UTC))

package towerdefense; import java.io.*; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class TowerDefense extends JFrame implements ActionListener { public static void main(String[] args) { new TowerDefense(); } Timer timer = new Timer(1, this); JFileChooser openDialog; int boardWidth; int boardHeight; int tileSize; int pathLength; int[][] coordinates; int[][] directions; boolean[][] board; int maxHealth = 20; int health = maxHealth; Enemy enemy; public TowerDefense() { super("Tower Defense"); //Store the map as an array this.setPreferredSize(new Dimension(getToolkit().getScreenSize().width, getToolkit().getScreenSize().height)); this.setExtendedState(MAXIMIZED_BOTH); this.setDefaultCloseOperation(EXIT_ON_CLOSE); this.getContentPane().add(new JCanvas()); this.setVisible(true); timer.start(); } public void actionPerformed(ActionEvent e) { if (health > 0) { if (enemy.move()) { health--; } } repaint(); } public void showErrorMessage(Exception e) { //Display an error message } class JCanvas extends Canvas { public void paint(Graphics g) { //Draw stuff } } }

--204.184.214.2 (talk) 18:36, 17 September 2009 (UTC)

Did you follow Sean's and Nimur's advice, and read this? --NorwegianBlue ^talk 20:53, 17 September 2009 (UTC)

You only call your repaint() method when actionPerformed() is called. Is this what you wanted? (Do you understand how Swing ActionListeners work? This is the official Java Book on Swing Action Events, available free online). Notice how in my example code, I called this.repaint() in the constructor. You aren't ever actuating the repaint() function! You either need to fire some ActionEvents, or set up a thread to schedule repaint() calls, or some other method to ensure you are actually calling your painting code. I'm not sure what your various game object classes implement, but I think you intend those objects to fire ActionEvents. This is potentially functional; it might or might not be good architecture depending on your game application's needs (ActionEvents are supposed to be fired when buttons are clicked, e.g. - but if you want, you can fire them when the game state changes, too). However, my guess is that your objects are never actually sending action events to the event listener. You might seriously consider a separate thread scheduling repaint(), independent of any UI events, to guarantee that the paint code is called (even if no game events have occurred). This will ensure that there's always a fresh version being painted on-screen. Nimur (talk) 21:37, 17 September 2009 (UTC)

Websites That Will Translate Letters -- Not Just Text From The Internet

Hello,

I've recently come across a few letters in a family archive that are in Dutch, Polish and Italian. Are there any places I can post scans of these to have them translated?

Thanks in advance for any help,

--Grey1618 (talk) 22:58, 15 September 2009 (UTC)

If they're not too long, you might find people on the Language Reference Desk who will do it. Otherwise, you'll probably have to type in the text. --Sean 00:11, 16 September 2009 (UTC)

You mean places where you can hire human translators? Yes, a web search should find tons of them instantly. You could also try something like craigslist to find someplace local. There is no Babelfish for handwritten texts, and anyway if these are family letters that might contain private info, you are better off hiring someone under terms of confidentiality, than posting scans on the internet to be spread all over. 67.122.211.205 (talk) 07:53, 16 September 2009 (UTC)

September 16

Quick Java question

Hello! Just a quick couple of questions I've been wondering: Is there a memory disadvantage to importing an entire package (e.g. import java.io.*) instead of individual classes? My guess is no, because I learned that Java loads classes lazily. My second question is regarding the finally{} block. Does it really serve a purpose? Once an exception is caught, as long as the catch{} block does not call java.lang.System.exit(int), the following code is executed, whether it's in a finally block or not. Thank you!--el Aprel (^facta-_facienda) 02:10, 16 September 2009 (UTC)

Import has no effect on the compiled bytecode. Only the compiler sees the import statements, the JVM that executes the code (or compiles it into machine code) doesn't know what you imported.

Often the code after the try/catch/finally structure is not executed. The catch block might not be present, or it might log the exception and re-throw it. Or the catch might catch something like IOException, but if there is a programming error and a NullPointerException is thrown, the catch won't handle that. So finally becomes the right place to close file handles and such. 62.78.198.48 (talk) 04:37, 16 September 2009 (UTC)

It's been a while since I wrote Java code, but I think that if it didn't have the finally feature you would have to change code like this:

try {
    somethingThatMightThrow();
} catch (SomeException e) {
    // handle SomeException
} finally {
    // clean up stuff from the try block
}
...

to this:

try {
    somethingThatMightThrow();
} catch (SomeException e) {
    // handle SomeException
} catch (Throwable t) {
    // clean up stuff from the try block
    // and then rethrow t
    throw t;
}   
// clean up stuff from the try block
...

That's not great, since you have to duplicate the cleanup code, and the rethrow will mess up your stack trace (I think). Exception handling is an area where C++'s RAII idiom is a lot easier to work with than languages like Java where you have no idea when/if destructors will run. --Sean 14:50, 16 September 2009 (UTC)

Except of course, when the cleanup itself can fail. As we know, destructors must not throw. Thus, you end up having to use the second alternative above anyway, even in the presence of deterministic destruction. Still, RAII is great for many common cases. decltype (talk) 14:58, 16 September 2009 (UTC)

C++ Destructors may throw as they wish. The danger is that a throwing destructor, might throw during stack unwinding too, confusing the environment as we suddenly have two exceptions to deal with at the same time. I would expect Java to get equally confused if, while executing a finally() block due to an as-of-yet unhandled exception, the finally block causes another exception to be thrown. Unilynx (talk) 21:36, 16 September 2009 (UTC)

That is why exceptions are scoped in Java. The compiler will require a unique name for each exception, including those in the finally{} block. Another try/catch/finally or throws clause must exist for an exception thrown in a finally block. There can be no ambiguity about which exception is being processed by a given catch block. Nimur (talk) 22:34, 16 September 2009 (UTC)

It's not correct to say that C++ gets confused by two exceptions at the same time. The behavior -- terminate() -- is well-defined, but not what most people want to happen. --Sean 13:13, 17 September 2009 (UTC)

Java doesn't get confused in this situation, it just has a "last exception wins" policy. An exception thrown from a catch or finally clause just leaves the function immediately and forgets about the exception that was being handled. I guess C++ couldn't use this approach because it doesn't have native garbage collection, so things still on the stack would never have their destructors run. --Sean 13:39, 17 September 2009 (UTC)

They would, because unwinding picks up where it left off whether or not the original exception is replaced by another. I don't think it would be hard to destroy the preempted exception object either, since there must be a mechanism for doing that in the catch (...) case. I assume they must have chosen terminate() because they thought it was the right thing to do. I'm not sure Java's choice is a good one, since errors that occur during cleanup from a failure tend to matter less than the original failure. On the other hand, C++ is kind of inconsistent, since the usual idiom for cleaning up only on failure is catch (...) { /*cleanup*/ throw; }, and there the last exception wins. -- BenRG (talk) 14:39, 17 September 2009 (UTC)

I've just read in D&E that the big debate at the time was whether to allow exception handlers to resume at the point-of-throw after doing some resource-freeing or whatever, which would have been deeply weird for us non-Schemey-types. --Sean 16:06, 17 September 2009 (UTC)

You are neglecting to consider try-finally blocks. You should only catch the exceptions that you can appropriately handle. Anything else should not be caught. This scenario introduces a common pattern: try-finally blocks without any exception catches. In this case, a finally block is the only way to guarantee a chance for cleanup. Another common pattern is to return values from within a try block. Again, a finally block is the only structured way to allow for any necessary cleanup. try-catch-finally may not technically be necessary, but, just as in a try-finally, putting any cleanup code in a finally block is best practice, regardless of the possibility of exceptions. It also promotes clearer and more maintainable code. 124.214.131.55 (talk) 15:55, 16 September 2009 (UTC)

Google Chrome: Recent Bookmarks bar

Yesterday, Google updated Google Chrome, but I didn't see any changes until this morning (even though I had the computer downloading all night). The New Tab page now holds 8 instead of 9 most visited pages and the blue bar with recent bookmarks has completely disappeared. Has anyone got an idea how to restore this, or at least get the recent bookmarks feature back? —Preceding unsigned comment added by 131.211.211.117 (talk) 08:00, 16 September 2009 (UTC)

Do a system restore, or, there are some previous builds here http://build.chromium.org/buildbot/snapshots/chromium-rel-xp/

77.86.47.174 (talk) 10:12, 16 September 2009 (UTC)

You could tell them you don't like the new one via http://www.google.com/support/forum/p/Chrome?hl=en 77.86.47.174 (talk) 12:10, 16 September 2009 (UTC)

There is a far better way below, ask if you get stuck implementing it.87.102.94.154 (talk) 19:37, 16 September 2009 (UTC)

See http://www.google.com/support/forum/p/Chrome/thread?tid=0fca9ffc66018150&hl=en 77.86.47.174 (talk) 12:18, 16 September 2009 (UTC)

But thank God (or, more, appropriately, the Google Chrome developers) that HTML accesskeys are working again. --Andreas Rejbrand (talk) 12:43, 16 September 2009 (UTC)

Remote Desktop Server

I've come across references to this but the remote desktop article doesn't say what it is or what functionality it provides... FT2 ^{(Talk | email)} 13:18, 16 September 2009 (UTC)

You are probably looking for Remote Desktop Services, which specifically describes the Microsoft implementation. The main remote desktop article is only a general overview of this type of software. Nimur (talk) 14:26, 16 September 2009 (UTC)

Close, but still lacks basic information. There are several terms (or systems) used in the Microsoft world - Remote desktop connection, Remote Desktop Services, Windows Desktop Sharing, and Remote Desktop Server. I can't find a side-by-side explanation of what they each mean or the differences between them. FT2 ^{(Talk | email)} 15:53, 16 September 2009 (UTC)

Terminal Server is the server. It typically runs on Windows Server, but can run on the professional desktop versions such as Windows Vista Business. Remote Desktop Client is the client. It is available on all Windows platforms since Windows 2000 (I think). Remote Desktop Protocol is the technical description of the connection scheme between client and server. Windows Desktop Sharing is a new technology which changes the login-session paradigm (i.e. you can connect to a "desktop" of an already-logged-in-user). Previously, Terminal Services created a new login session for each connected instance. What information are you seeking that was not already in the Remote Desktop Services article? "Side-by-side comparison" is not really suitable, because these are individual components of the Remote Desktop Services system, not interchangeable tools with comparable feature sets. Maybe the official Getting Started guide from Microsoft is the best place to start, if you don't know the terminology. Nimur (talk) 17:10, 16 September 2009 (UTC)

Apparently (so it seems) "Remote Desktop Server" is a differentiating item between various versions of Windows 7. I couldn't find an answer what exactly this would do (or what its omission would prevent a user doing) to see what it was that was so significant as to differentiate two editions. There isn't a clear answer anywhere on the web what a prospective purchaser can do with this, that they couldn't do without it. FT2 ^{(Talk | email)} 01:17, 18 September 2009 (UTC)

You are correct. As in previous Windows releases, the remote desktop server is only available in those versions of Windows which are branded for "Server", "Business", or "Professional" use. This means that these versions will be able to host remote desktop sessions - that is, your personal computer can operate as a server. (Are you still confused what "remote desktop server" means? It means that you can be sitting at a different computer, but connect to your server over the network, and use its applications, access its hard disk drive, and see the windows open on its desktop). All versions of Windows (including those which lack the remote desktop server) have the remote desktop client - so they can connect to other computers which are hosting remote desktop server. But only certain (more expensive) versions allow you to connect into the computer. Maybe if this is not clear you should read our article called client-server to conceptualize the distinction between remote desktop server and remote desktop client. Nimur (talk) 04:00, 18 September 2009 (UTC)

I think you touched on it enough to explain the difference. So a lesser specification would imply one can connect to, but not be connected by (in any way)? I had thought "Server" meant it would allow some form of multi-user remote desktop conferencing or other more sophisticated functionalities. Simply being able to be connected into as a remote desktop by another user... that's basic these days for technical support and so on, to be able to connect to the remote machine and help the user directly. How will that work, when most new Windows adopters will be on PCs that don't have it and can't be connected into? Won't that be fairly detrimental to a wide range of IT support services in the domestic and corporate worlds? Any help finding a reference on this to read? FT2 ^{(Talk | email)} 04:10, 18 September 2009 (UTC)

As I mentioned above, that is why the more expensive "Business" versions do include this feature. I linked the Getting Started guide above. There are lots of references from there, provided by Microsoft. Everything from tutorials to research and technical whitepapers can be found linked from the Getting Started guide. Nimur (talk) 15:29, 18 September 2009 (UTC)

norton vs avast

Hi, I am running XP on a PC and Vista basic on my new laptop.

On my PC I use the free version of Avast which does fine. On my laptop I have 40 days left of Norton which runs very smoothly...

What do you recommend? Should I get a cheap 2009 version of Norton from Amazon or ditch it completely and use Avast free version on my laptop?

cheers! —Preceding unsigned comment added by 89.241.127.92 (talk) 16:05, 16 September 2009 (UTC)

Have you considered alternatives like Comodo AV, Avira, NOD32, Kaspersky, or the upcoming Microsoft Security Essentials? (2 out of 5 are free, and I reccomend all over Avast and Norton). Btween Avast and Norton, I reccomend Avast though. —Preceding unsigned comment added by Caltsar (talk • contribs) 16:36, 16 September 2009 (UTC)

Which of the two free ones is best? Are you ready for IPv6? (talk) 17:07, 16 September 2009 (UTC)

I just recently dumped norton, which has annoying pop-ups every time you try to download or save something, and replaced it with avast, so far I've been very happy with it--Jac16888^Talk 17:27, 16 September 2009 (UTC)

I personally like MSE, but it's still in a limited beta. Before that, I was using Comodo, but I only like their AV product and not their firewall. Avast is definately good, but the interface and the general "speed" of it puts it just out of my top 5. Both Comodo and MSE are free. Avira has a free version, but it nags you to upgrade once a day/week or something. The most expensive on my list is NOD32, but it makes up for the price in having a very light footprint.Caltsar (talk) 18:39, 16 September 2009 (UTC)

When I first moved to China I picked up a worm from my company's network that absolutely no virus scan could get rid of. I couldn't even google it because it was some domestic Chinese virus that just made a few hidden folders and tried to propogate via autorun. Chinese virusscan software was useless. I ended up getting Kaspersky, which was able to notice the virus' activity but wouldn't kill it because it didn't know what it was. Using their in-program instructions, I submitted the virus to them for analysis and they deconstructed and added it to the virus database within 48 hours. After my next update I was finally rid of a bug that's basically on every computer in NE China. I can't afford Kaspersky these days, but I'll never forget how satisfied I was with their service. 218.25.32.210 (talk) 01:08, 17 September 2009 (UTC)

Another alternative program is AVG, which is a amazing free antivirus, which has all the features of a paid-for antivirus program, which are sometimes really expensive when you can get all the same features and protection for free. I currently use it on my PC and it works brilliantly. Chevymontecarlo (talk) 12:14, 21 September 2009 (UTC)

Computerisation of the Nigerian Judicial System

please what can make up the chapter three of my project on the topic çomputerisation of the Nigerian Judicial System —Preceding unsigned comment added by Awugo (talk • contribs) 17:12, 16 September 2009 (UTC) Question restored by AlmostReadytoFly (talk) 08:05, 17 September 2009 (UTC)

What makes up chapters 1 and 2? AlmostReadytoFly (talk) 08:05, 17 September 2009 (UTC)

Learning the R statistical language - any statistical textbooks that use R?

I would like to become proficient in R (programming language), and my statitical knowledge is a little rusty. Are there any statistical textbooks that use or teach R at the same time, especially with regard to time series? I am aware of R Commander. The online introductory material I've seen for either R or R Commander are just bare-bones listings of what they do. I'd like to be set for example exercises that start me using the language. I am not a programmer so need more than just a list of commands. Thanks 89.243.195.226 (talk) 19:18, 16 September 2009 (UTC)

"Introductory Statistics with R" sounds promising. Also check out the "similar titles" section. --Sean 20:13, 16 September 2009 (UTC)

• I've got that one( Peter Dalgaard, "Introductory Statistics with R", 260 pages). It mainly covers how to perform standard statistical tests (hypothesis testing) in R, it's a "cook book" but doesn't really teach you how to use R as a programming language.
• In addition, I've got "The R book", by Michael J. Crawley, Wiley, 2007, 942 pages. It is a must if you want to be proficient in R as a programming language.
• I've also got Michael J. Crawley's "Statistics. An introduction using R", Wiley, 2005, 304 pages. It covers some of the same stuff that Daalgaard's book, but the approach is slightly more theoretical, and there is more focus on R as a programming language. It's a better choice than Dalgaards book for an introductory text, IMO.
• Finally, I've got "R graphics", by Paul Murrel, Chapman & Hall 2006, 291 pages. If you want to use R as a graphics engine (which I do), it, too, is a must.

--NorwegianBlue ^talk 19:28, 17 September 2009 (UTC)

System freezing because of RAM ?

Hello there, Can a RAM Cause system to freeze (both randomly or running system for several hours)? (Screen or game freezes on desktop) Thank you--119.30.36.39 (talk) 20:00, 16 September 2009 (UTC)

Yes, certainly. Searching for "bad RAM" shows that random lockups are a common symptom. --Sean 20:21, 16 September 2009 (UTC)

There's freeware programs that can test your RAM to see if it's bad. Are you ready for IPv6? (talk) 21:24, 16 September 2009 (UTC)

RAM can cause it, a bad HD can cause that, even overheating can cause that... test the RAM and see if it's really the problem before you replace it. You can test it with memtest86. --98.217.14.211 (talk) 21:26, 16 September 2009 (UTC)

If you're computer is running slowly then it's probably in isue with the ram. i.e. you game looks like its lagging etc. if not then i would also suggest that if you're using a computer desk that has a "place" for your tower to sit in with a door in front of the tower to either A) open your door while the computer is on B) drill 2 inch holes in the back of the desk or C) take the tower out completely. If you have Low hard drive space this could also be an issue. If you're running Vista i would suggest no lower then 1 GB of ram ESPECIALLY on a laptop.

--JD's Web Service 13:47, 18 September 2009 (UTC)

September 17

Editing MIMEs in Firefox 3.5?

Just curious how to edit MIME mapping in Firefox 3.5. There was an add-on called MIME Edit, but it doesn't work with v3.5. I'm trying to get Firefox to properly send .7z and .XAR files to the correct decompression utility. --70.167.58.6 (talk) 00:01, 17 September 2009 (UTC)

Mouse Focus & Installing Software Under Security Measures

Alright, I'm on a Windows XP, Version 5.1.2600, and I have two questions.

1. When I open the start menu using the Windows logo button on my keyboard, and my mouse happens to be in the same place that the start menu appears, the mouse takes focus, and possibly opens a side-menu that I don't want to open. Is there any way to get it to listen to the keyboard by default, and to the mouse only if I jiggle the mouse?

2. I am on a non-admin account, to prevent software getting installed that I don't want installed. Ideally, when I download an installation program from my non-admin account, I should then be able to switch user and install from the admin account. For some reason, however, my computer decides to do two (possibly related?) things when it downloads the installation program: it makes the file read-only (is this because it's large, and making it read-only saves memory?), and it locks the file from other users. I am explicitly putting the file into shared documents, which I think would make it clear that I want it to be shared, but my computer wants to make it inaccessible for my admin account. How do I prevent this from happening?

thanks, --129.116.47.61 (talk) 01:33, 17 September 2009 (UTC)

For what it's worth, I just tried #1 under Vista and its behavior is the way you want it; so, one way to get it to do this would be to upgrade to Vista. I salute you on your #2 item, running as a non-admin. I am a bit surprised that a downloaded file would be inaccessible to an admin. What happens when you try right-clicking it and opening it as an administrator? Tempshill (talk) 06:14, 17 September 2009 (UTC)

I'm not very likely to be upgrading to Vista anytime soon, so that doesn't do me any good. I was wondering if there is some setting hidden somewhere that would do what I want?

Running it as an administrator from my non-admin account still suffers the same problem. Is that what you were talking about, when you said to "try right-clicking it and opening it as an administrator"? --129.116.47.61 (talk) 13:23, 17 September 2009 (UTC)

No one else has any answer? That makes me sad. :( --129.116.47.61 (talk) 23:00, 19 September 2009 (UTC)

Firefox Plug to Download Every Web Page Visited?

I'm trying to find if there is a firefox plug-in that will automatically save a local copy of every page I visit on my hard drive. Anyone know if it exists?

--Grey1618 (talk) 04:36, 17 September 2009 (UTC)

Shelve Itseems perfect for you. Saves to folders of your choice, configurable templates, and can be set to save automatically and write a log file. - KoolerStill (talk) 16:25, 20 September 2009 (UTC)

Automatic switch on

Is there any software or any method which will enable my PC to be automatically switched on from hibernate mode, at a specific time, and to automatically connect to the internet, and run a program I specify (for example, Bit Torrent)? Thanks in advance. 117.194.224.227 (talk) 08:42, 17 September 2009 (UTC)

Yes. In Windows it's called "Scheduled Tasks" and can be found in the Control Panel. Some how-to guides are available. (I'm in the middle of trying to get mine to start playing BBC Radio 1, but opening up a specific web link is slightly trickier.)

If you're running a Unix-like system, I think you want cron. AlmostReadytoFly (talk) 09:11, 17 September 2009 (UTC)

I don't think these work when the computer is hibernating. When it's on hibernate, the computer is completely off, no processes are run, especially not cron or the Scheduled Tasks service. The only thing I can think of is some sort of wake-on-lan solution, but then you need something else to wake the computer up, so it seems to defeat the purpose.

Easiest solution: keep the computer on, and use RSS feeds with your bittorrent client to automatically start downloading stuff. 195.58.125.104 (talk) 09:52, 17 September 2009 (UTC)

Easier solution: just put your pc on standby. It hardly consumes any power, can be up in seconds, and scheduled tasks work with it. I used to play a playlist every morning.

No, it does work (for Scheduled Tasks at least) if the computer is hibernating rather than shut down. I've used it many times. In the Properties of a Scheduled Task, there's a Settings tab with a Power Management section. "Wake the computer to run this task" needs to be checked. AlmostReadytoFly (talk) 10:47, 17 September 2009 (UTC)

Some motherboards allow you to configure a power cycling schedule from the BIOS. This supersedes any software program control for powering on or off. Nimur (talk) 15:39, 17 September 2009 (UTC)

Thanks. I was able to make BitTorrent run on its own after waking up from hibernation automatically, but I can't schedule automatic internet connection. Please help. Is there any way I can write a command prompt program that will connect to the broadband when run?? 117.194.229.189 (talk) 14:01, 18 September 2009 (UTC)

Browser 3d

O3D , 3d CSS elements , html 5.. All these have some form of 3d functionality. I want to make a category, something like "browser based 3d graphics technologies" or something..

Can your expertise supply further examples if they exist. Also found Web3D.

Also maybe there is already an article describing this topic - it looks like there are too many different methods at present - is there a standard, or any attempt to make a standard? Thanks.87.102.94.154 (talk) 09:57, 17 September 2009 (UTC)

Lets not forget our history and include VRML and it's successor X3D. They are pretty much attempts at creating an internet 3d "standard". 195.58.125.104 (talk) 10:06, 17 September 2009 (UTC)

Also I'm wondering about the term Web3D - the article gives the impression that it is a coverall term, but it seems to be associated with the Web 3D consortium - do people use the term "web3d" for all browser based 3d, or is it just some wiki editors idea?87.102.94.154 (talk) 10:18, 17 September 2009 (UTC)

memtest86 on CD

Hello there, I have just downloaded memtest86 and unzipped it. After unzipping a new file memtest86.ISO appeared. Should I write memtest86.ISO file on CD or unzip it again? Thank you--202.56.7.153 (talk) 11:00, 17 September 2009 (UTC)

.iso files are ISO images of CD's and DVD's. You need an image burner like imgburn to burn it onto a CD. --antilived^{T | C | G} 11:10, 17 September 2009 (UTC)

memtest86 is a program that, if I recall, runs as a boot disk (you boot from the CD). So you need to burn it to a CD. --98.217.14.211 (talk) 13:49, 17 September 2009 (UTC)

98 is correct. You are supposed to burn the .iso to a CD or DVD, then boot from it. Memtest86 will load and start testing your memory for as long as you allow it to run. Comet Tuttle (talk) 16:48, 17 September 2009 (UTC)

• How much time (appropriate time) I should run memtest to test the ram? Thanks--119.30.36.54 (talk) 18:02, 17 September 2009 (UTC)

At a minimum, let it run through one cycle of all the tests, which will take an hour or two, depending on the speed of your RAM and how much you have. Overclockers and other people concerned about stability will often let it run for 24 hours. Of course, as soon as Memtest finds errors, you know the RAM is bad and don't need to let it run any longer. --Carnildo (talk) 00:18, 18 September 2009 (UTC)

Command promt

Can I use command prompt to message another computer?Accdude92 (talk) (sign) 13:24, 17 September 2009 (UTC)

In what way? ssh or irc are likely to be what you want. --194.197.235.240 (talk) 13:35, 17 September 2009 (UTC)

Using the command prompt like im.Accdude92 (talk) (sign) 13:47, 17 September 2009 (UTC)

What operating system are you using? decltype (talk) 13:51, 17 September 2009 (UTC)

XpAccdude92 (talk) (sign) 14:06, 17 September 2009 (UTC)

It is irc then. If you want to do this just for the sake of something new, I recommend emacs for the client. --194.197.235.240 (talk) 14:29, 17 September 2009 (UTC)

Within a LAN, it may be possible to use the net send command. I am not sure, but I think that's limited to local networks, i.e. you can't send a message to a random friend in another location. --LarryMac | Talk 15:31, 17 September 2009 (UTC)

The widely-known Pidgin (software) has a console version for most operating systems called Finch. Here's the help page. It's much easier to install on Linux/Unix systems, but you can run it on Windows as well. Nimur (talk) 16:29, 17 September 2009 (UTC)

(Er, I guess the Windows Cygwin port is no longer developed). Nimur (talk) 16:32, 17 September 2009 (UTC)

document.getElementsBy

So i have some java script and I want to "document.getElementsBy" the value 1234567 from

<input type=hidden name=resto value="1234567">

How do I do this? Thanks for your help!!

It's not automatic—basically if there isn't already a supported method (e.g. getElementById) you have to write a custom function that will cycle through all elements on the page and see if they have that value. (If there is any way just instead get it by its name or its ID, those are both a lot easier). --98.217.14.211 (talk) 15:23, 17 September 2009 (UTC)

Here's a function that ought to work. Basically it goes through all "INPUT" tags, looks to see if the value is what you wanted it to be, and then returns a pointer to the first element it finds that matches that value. If it doesn't find any, it returns false. If you really need it to return elements (more than one), it would not be hard to modify to return an array of all found control ids.

function getElementByValue(checkValue) {
	for (i=0;i<document.getElementsByTagName("input").length;i++) {
		var ctl = document.getElementsByTagName("input")[i];
		if(ctl.value==checkValue) {
			return ctl;
		}
	}
	return false;
}

--98.217.14.211 (talk) 15:26, 17 September 2009 (UTC)

A Javascript toolkit makes these kinds of things much less tedious. This Prototype snippet does what you want:

var my_elements = $$('input[value="1234567"]');

$$ is just a normal function ("$" is a valid identifier character in Javascript) that takes a CSS selector -- which is a pretty convenient way to zip around a DOM tree -- and returns matching elements. --Sean 16:22, 17 September 2009 (UTC)

Eh, if it's for a simple job, the straightforward approach is both quicker, simpler, and doesn't require learning a whole new syntax (much less including an extra 140KB of scripts you won't use). In principle I think toolkits are a good idea (esp. because cross-platform js is hard), but knowing how to do it in the raw language is a valuable thing in an of itself. "Convenience" is not generally an always-good-thing when it comes to good programming. --98.217.14.211 (talk) 16:32, 17 September 2009 (UTC)

While your points are valid, I think learning the new syntax (advanced CSS selectors) is probably a lot easier than learning to use, optimise, and debug lots of DOM functionality. For instance, in your example, will the repeated calls to document.getElementsByTagName("input") be optimised, or will this perform poorly if there are many input elements on the page? Using a library lets you avoid (many of) these pitfalls, as the library's authors have already looked into them.

The current "minified" download of jQuery weighs in at 55KB, or 19KB when transmitted using gzip compression. While this is still a lot if you're only using it once, the chances are that if you're doing this kind of manipulation, it will be useful elsewhere on the page as well. - IMSoP (talk) 15:48, 18 September 2009 (UTC)

Minitab Learning?

I am very new to this statistical software called Minitab, how do I go about mastering it as the book seems to be very less helpful, are there any videos we can download and learn as I do learn from visuals more than the text. Anyone please help..

RAM question

I friend of mine has recently built a new PC. Unfortunately, he did not pay enough attention when picking the RAM modules, and ended up buying something that is not on the approved list for the particular motherboard he is using. The RAM does not work in dual-channel configuration at all, so he installed it as single-channel for now. Now, every time he turns his PC on, it either reboots mid-POST or hangs up when Windows starts to load (in which case a manual reboot in needed). When the PC boots up for the second time, there are never any problems, and he is yet to experience a single problem in Windows that can be attributed to non-compliant RAM. Any subsequent reboots are also flawless; it takes powering the PC off completely and waiting for at least a couple hours to reproduce the problem.

We both realize that to fix this he needs to buy fully compatible modules, but I nevertheless am curious as to the nature of the problem. Why does it always (and I mean always) take another reboot to get in after the PC has been off for at least a couple of hours?—Ëzhiki (Igels Hérissonovich Ïzhakoff-Amursky) • (yo?); 16:44, September 17, 2009 (UTC)

I've never bothered to check the compatibility list of a particular ram to a motherboard - as long as it's something the motherboard accepts (eg. DDR2 or DDR3) it would usually work. Is this maybe a new Core i7 rig? The i7's have the memory controller built into the CPU which has stricter requirements - namely a lower voltage than previous DDR3's. Perhaps you bought higher-voltage DDR3 ram and it doesn't intialise properly while everything is starting from a cold boot (high current drain pulling down the voltage from the PSU), but after the initial current rush (eg. spinning up hard drives) the voltages go back to normal and everything function properly once again. However this is purely speculation, so don't take my word on it. --antilived^{T | C | G} 06:12, 18 September 2009 (UTC)

Speculation is OK :) It's not like anything important is going to be affected; I am merely curious why the things are the way they are. Incidentally, this is not an i7 rig; it's a Q8400. In light of this, would your voltage drain explanation still apply? Thanks much!—Ëzhiki (Igels Hérissonovich Ïzhakoff-Amursky) • (yo?); 12:06, September 18, 2009 (UTC)

Unless the PSU is near/over its capacity I don't think it's a likely cause. I have a similar system (Q6600 + 4GB DDR2 ram on a 620W PSU), overclocked, and I've never had that problem before. Can you give more information about the system, like motherboard chipset, ram model and power supply model? --antilived^{T | C | G} 13:32, 18 September 2009 (UTC)

Nope, it's a 750W PSU, and it's hardly near its capacity. The RAM is DDR3, though. Anyway, I don't have the exact specs/models at hand, but I'll get them from my friend and post them here later today or tomorrow. Thanks for your willingness to help!—Ëzhiki (Igels Hérissonovich Ïzhakoff-Amursky) • (yo?); 16:05, September 18, 2009 (UTC)

How much does it cost to start a wiki?

Technically, I know little more about wikis than to post content such as this question. I have an idea what the content would be. How much would it cost, in terms of time and money, would it cost to set up a wiki like Conservapedia, Citizendium, or these two? http://wikiindex.org/Welcome http://royalist.ca/wiki/Main_Page Keep in mind, I'm in Canada. Thanks.192.30.202.13 (talk) 18:28, 17 September 2009 (UTC)

Every part of the Wiki software that runs Wikipedia, including MediaWiki and the back-end server software (Apache server and MySQL) are free free software - which means that they are available at no cost and with a very open legal license permitting their use and customization for almost all purposes. Further, these can be run on free operating systems. This means you can run the wiki for zero cost. You will possibly need to purchase a web hosting service, or own a computer with a viable network connection (such hardware may cost you money). Do you need assistance setting up a MediaWiki installation? There are lots of tutorials available, such as the official Installation Guide. There are other competing tools, servers, and wiki softwares available, but I have found the easiest to set up is MediaWiki on an Ubuntu server. Nimur (talk) 18:34, 17 September 2009 (UTC)

Thanks Nimur. (I checked your user page. Impressive :-)
The thing is, I don't have a lot of money, but I have a fair amount of time--the lowest 10% in the socio-economic spectrum. I'm thinking of a few, maybe several, $100's.192.30.202.11 (talk) 19:46, 17 September 2009 (UTC)

I would investigate Internet web hosting providers that advertise that their hosting services allow for a Wiki installation. (Specifically, MediaWiki would probably be preferable — it's the framework Wikipedia uses.) Then you won't need any hardware but will need to pay the US$20 per month or whatever that they charge you for the hosting services. Comet Tuttle (talk) 20:12, 17 September 2009 (UTC)

Again, it's virtually free to set up a MediaWiki installation, but making it available to the internet at large requires a network connection and enough computing power to satisfy the demand. Low-cost hosting is available from ~ $10 per year from many commercial web hosting providers ("renting space on somebody else's server"), and if your website and wiki receive low- to medium- traffic, this is suitable for your needs. If you expect a very large volume of visitors (e.g. tens to hundreds of unique visitors per minute - or if you anticipate regular large file transfers/video hosting), hosting costs increase dramatically. You probably want a host with shell access so you can configure your wiki install; or a provider who will set this up for you. Nimur (talk) 20:29, 17 September 2009 (UTC)

Maybe we're thinking of different providers, but most of the "cheap but not rickety" providers (e.g. dreamhost, bluehost) are ~$10 per month, not year. Which is still pretty cheap, but not <$1 per month, if you want something that will give you the kind of space and control that I imagine installing MediaWiki requires. --98.217.14.211 (talk) 13:37, 18 September 2009 (UTC)

See Comparison of wiki farms for more options. You may be able to get started at no cost, if you choose a free provider. If you plan to invite the general public to participate in the wiki, you should keep an eye on the copyrights to be sure you will be free to move it later to a different host. If you have no previous IT experience or hobbyist skills, setting up Mediawiki yourself would not be trivial. Being a site administrator on a wiki farm would spare you most of this trouble. EdJohnston (talk) 23:57, 17 September 2009 (UTC)

Great answers everyone--I'm using another computer hence different IP address. I will check all links. I suppose one last concern (at least one I can think of now), is the "what if." If my wiki does poorly with me being the main editor, I suppose I can go on the cheap. But what if it becomes as sucessful as Conservapedia, Citizendium, or Wikinfo? Should I have a large memory and traffic capacity to begin with as the price might be reasonable, or is there the possibility of going little memory to big memory--possibly transfering memory--such as articles, with dates of edits intact. Thanks to all, and a happy weekend to all.:-)206.130.173.55 (talk) 17:20, 18 September 2009 (UTC)

Get something cheap. If you suddenly become massively popular, you can export the database and put it on a new server, which you can then shop for and price according to your new needs. It's relatively easy to transfer the data from one server to another ("relatively" meaning, it can be done, it's not too difficult for someone technically inclined, though if you were yourself trying to do it, you might have to ask for someone on here to help you). --98.217.14.211 (talk) 23:00, 18 September 2009 (UTC)

AJAX vs. jQuery?

Can someone explain to me the different between AJAX and jQuery? Like dumb it down to Homer Simpson level. I'm seeing a lot of interactive effects (like menu accordions, scrolling pages, shadowboxes and slideshows) that are jQuery. I thought you needed to use AJAX to acheive those type of modern web 2.0 effects. I've read both Wikipedia entries, but they are too technical to wrap my mind around. --70.167.58.6 (talk) 21:01, 17 September 2009 (UTC)

From what I know, AJAX is a technology that allows you to pull information without reloading the whole page, and jQuery is a Scripting Library that has pre-written functions which use AJAX. PrinzPH (talk) 22:06, 17 September 2009 (UTC)

• jQuery is a library that aims to make programming on web pages with Javascript easier (and, in my experience, succeeds). It has various pieces of built-in functionality, primarily to do with manipulating the content currently shown on screen, but also acts as a framework to build more complex functionality - it sometimes feels a bit like a language in its own right.
• AJAX is a technology for pulling data from multiple sources onto one page while you're viewing it, such as to dynamically replace part of a page based on user input, giving the page a more "desktop-like" feel. jQuery has built-in functions for performing basic AJAX operations.
• No AJAX is needed to create the visual effects themselves, if all the content for the slideshow, lightbox, menu, etc is already on the page when it loads (even if it's not visible). For that matter, neither is jQuery, or any other library - they simply offer additional abstraction making the effects easier to program. - IMSoP (talk) 00:10, 18 September 2009 (UTC)

September 18

Where did my question go?

Hi,

I distinctly remember posting my question about asp just a couple of hours ago... How come I can't see it anymore? :( PrinzPH (talk) 01:40, 18 September 2009 (UTC)

Are you talking about the one that a user deleted here? It may have been a completely accidental deletion. -- kainaw™ 02:07, 18 September 2009 (UTC)

Yeah thats the one! :) How do I restore it? (wiki noob) PrinzPH (talk) 02:29, 18 September 2009 (UTC)

I restored your question about ASP from the history. It's the following section. EdJohnston (talk) 02:41, 18 September 2009 (UTC)

Thanks Ed! :D PrinzPH (talk) 02:57, 18 September 2009 (UTC)

Sorry everyone! That seems to have been my fault - I got an edit conflict screen, which are an absolute nightmare on long pages like this one. And I really should stop editing in the middle of the night... - IMSoP (talk) 14:32, 18 September 2009 (UTC)

Code in 'included' ASP Files

Resolved

Hi All,

Was playing around with ASP, and came upon a slight problem:

Say I have 2 files, index.asp and something-to-include.inc

In index.asp I have

<%
dim activeButton
activeButton = 3
function button(x)
	button = "button=" & x
end function
%>

!some html elements here!

<!-- #include file="something-to-include.inc" -->

and in something-to-include.inc i have:

<object type="application/x-shockwave-flash" width="850" height="381" data="flash/header_v8.swf?<% button(activeButton) %>">
    <param name="movie" value="flash/header_v8.swf?<% button(activeButton) %>" />
    <param name="quality" value="high"/>
</object>

My problem is that the index.asp page doesn't seem to evaluate the code in the inc file, leaving just ...data="flash/header_v8.swf?">

I know that code works when I hard-code the contents of the inc file into the ASP file, how do i get it to work from an #include call?

Thanks in advance! PrinzPH (talk) 20:20, 17 September 2009 (UTC)

Almost forgot, I NEED to be able to declare 'activeButton' from the main ASP/calling page (improvising on a template thingy). PrinzPH (talk) 20:23, 17 September 2009 (UTC)

In the .inc file, <% button(activeButton) %> should be <% =button(activeButton) %>. AndrewWTaylor (talk) 10:19, 18 September 2009 (UTC)

NICE! Thanks Andrew! PrinzPH (talk) 21:32, 18 September 2009 (UTC)

CAESAR piping software

Hi Anybody can send me CAESAR piping stress analysis software

? You can get it here. http://www.coade.com/

83.100.251.196 (talk) 11:05, 18 September 2009 (UTC)

Reference desk talk page

The talk page refuses to be edited but is not locked -temporary blip?83.100.251.196 (talk) 11:41, 18 September 2009 (UTC)

It's been semi-protected by Ten. Zain Ebrahim (talk) 12:18, 18 September 2009 (UTC)

Ah I see, shouldn't there be an icon (silver padlock) or something on there - I can't spot it.83.100.251.196 (talk) 12:23, 18 September 2009 (UTC)

Me too. I wonder why it's not there. Zain Ebrahim (talk) 13:07, 18 September 2009 (UTC)

Possibly hidden by the "skip to the bottom" button-box at the top-right of the page...83.100.251.196 (talk) 13:23, 18 September 2009 (UTC)

I don't think so. For me, (Beta, IE7) the "skip to the bottom" button goes under the line and the padlock goes above. Zain Ebrahim (talk) 13:34, 18 September 2009 (UTC)

Given how many IPs regularly edit the Reference Desk, isn't protection for four days a little much? It strikes me as a "one day at a time" sort of situation. A look at the history does not make clear to me why it was protected, nor is there any discussion on the page about why it was protected... --98.217.14.211 (talk) 13:28, 18 September 2009 (UTC)

I'm guessing that the edit causing the protection (see link above) was by ex-user"lightcurrent" - who has a "blue touch paper" effect on most admins - as far as I can tell they spend 99% of their time chasing him, his sockpuppets and other his other anonIPs - a behaviour not unlike the game Whac-A-Mole.

This is probably why the protection was immediate, and undiscussed.83.100.251.196 (talk) 13:41, 18 September 2009 (UTC)

Itunes

I have filled both of my hard drives with music and would now like to buy an external hard drive, and move itines and all my music over there. So, would this help to speed up my computer as I have heard, and how would I do this with out loosing any of the songs? Any help would be appreciated. Thanks ppl

I don't know to what you are reffering to as there is no link in your question. Please rephrase.

--JD's Web Service 13:52, 18 September 2009 (UTC)

No link should be necessary. If your hard drive is filled, then yes, expanding capacity will improve performance. Generally an internal drive performs better than an external drive, but for data like music and videos, an external drive is fine (and allows for easier portability if needed). Here's one of many articles explaining how to move your iTunes content to a new drive. — Lomn 14:09, 18 September 2009 (UTC)

Telephone/Voice Mail Oddity

A friend of mine recently told me about an odd experience. She was talking to someone else, normally, on the telephone, but when she hung up, there was a new message. It was a message for the person she was talking to. Is this even possible? Thanks, gENIUS101 12:19, 18 September 2009 (UTC)

I don't quite understand how it would be for the person she was talking to - maybe someone had just mis-dialled? Certainly many phone providers (both mobile and fixed line) have free voice mail facilities that kick in when the line is engaged. Often these don't allow you to record an out-going message, so if someone had both numbers and selected the wrong one, they wouldn't have realised they were leaving a message for the wrong person.

If it wasn't even a mutual contact that left the message, then I really don't know. - IMSoP (talk) 15:37, 18 September 2009 (UTC)

I don't think it was a misdial, as it was a work call for the person she was talking to. However, my friend did work there about 10-15 years ago, so that might be it, but it seemed unlikely to me. Thanks, gENIUS101 20:20, 18 September 2009 (UTC)

If I understand correctly, you are saying the other person was using a phone at their workplace and called your friend. After the call, your friend had a new voicemail message but it was meant for the other person.

If so, then this might have happened if the other person accidentally forwarded their workplace phone to your friend's phone.

Imagine the other person's workplace phone. Perhaps there's a "Call Forward" button right next to the "Outside Line" button. Or maybe the codes are similar, say *8 and 8. So perhaps the first time the other person tried to call your friend, they accidentally used the forwarding code without realizing it. They were expecting a ringing signal, but heard a confirmation beep instead, and so they just hung up and called correctly the second time.

While your friend and the other person were talking, a third person called the work phone, was forwarded to your friend's phone, and went to your friend's voicemail. Perhaps your friend's voicemail greeting is generic, and the third person thought they had the work phone's voicemail and left a message.

Perhaps after the call was over, the other person noticed an indicator on their work phone indicating it was forwarded and turned off the forwarding. --Bavi H (talk) 03:00, 19 September 2009 (UTC)

Why is C++ faster than MATLAB?

Hello, I am not very good at analyzing this stuff. I have to basically do a simulation involving fluid dynamics, Solid Mechanics and Acoustics all in one. My supervisor has asked me to implement it in C++ rather than in MATLAB, where it would be easier. My mesh will contain several thousands (or even millions) of elements. Why did he ask me to do it in C++? Thanks - DSachan (talk) 13:06, 18 September 2009 (UTC)

You should ask him. Perhaps he wants it to be used on a computer that doesn't have MATLAB. Perhaps he wants to share it with people who only know C++. Perhaps he wants it implemented directly instead of slowly parsed by MATLAB. Perhaps he wants you to fail because he is trying to downsize. Perhaps he is a complete idiot and doesn't know what either C++ or MATLAB is. -- kainaw™ 13:24, 18 September 2009 (UTC)

I don't know enough about the speed of MATLAB to give an answer, but the article says MATLAB is implemented in C. But it's dynamically typed which means it may be wasting a LOT of time checking the type of each element in each matrix before doing any calculation. Using C or C++, all the checking is done once at compile time, not repeatedly for each operation on any element in the matrix.

If you're doing it in C or C++ yourself, you'll need to use a software library to implement the matrix algebra. Use a good quality library rather than implementing it all yourself as the libraries are well tested and optimized to make them run as quickly as possible.

One possible reason for using C/C++ is that there are extensions and libraries for performing calculations in parallel over multiple processors. If you don't like C/C++, you could try FORTRAN, which is still very popular in academic circles (I used FORTRAN with LAPACK / NAG libraries Uni). Or even Python with SciPy (this is more similar to MATLAB but may still be a little slow).

I guess the most important bit is to talk to your supervisor and others on campus - if your supervisor only knows C, he can only help you with the problems you get in C. --h2g2bob (talk) 13:55, 18 September 2009 (UTC)

Matlab can be either intepreted or compiled, I'd assume for heavy maths it would be compiled first to avoid the issues you mention with the typing system.83.100.251.196 (talk) 14:08, 18 September 2009 (UTC)

Look at MATLAB#limitations : portable code is one good reason not to use it, and a reason to want it in C or another language.83.100.251.196 (talk) 14:08, 18 September 2009 (UTC)

But MATLAB is more portable than C! And now that GNU Octave exists, MATLAB-compatible code can run on all major platforms, operating systems, processor architectures, without purchasing software from The Mathworks. Nimur (talk) 15:17, 18 September 2009 (UTC)

I admit to being totally out of date.. but more portable? - maybe they see themselves using a non-intel processor in the future - in which case C++ or something would be a better choice, maybe even they have access to cell microprocessor??

I like the sound of C! (programming language) by the way :) 83.100.251.196 (talk) 15:54, 18 September 2009 (UTC)

There is a very prevalent misconception about "performance" in computational research. The idea is that MATLAB, or Java, or Python, are inherently slower because they are interpreted languages. Not only is this untrue (in the case of Matlab or Java, for example, the program can actually be compiled to machine code); it also betrays a 30-year-old understanding of computer processor architecture, and a misunderstanding that "extra instructions" must slow the processor down. In fact, interpreted instructions tend to be more predictable to cache prediction schemes, so executing more instructions may actually increase instruction throughput. A modern CPU or multicore CMP is so sophisticated that a conventional linear analysis of "instruction count" is meaningless when comparing two executables. The only way to determine which language implements a feature faster is comparative benchmarking. To say definitively whether MATLAB or C++ will implemenent your fluid simulation faster, you must code both and test them on the same machine and measure their actual execution time. That being said, it is certainly true that MATLAB has some features which can potentially slow the code down significantly. Dynamic type-checking is a possible issue, but this is probably the least of your worries. What is most troublesome is that MATLAB allows "transparent" activities to be interpreted by the execution environment - e.g., if you have two large matrices A and B, and you add A + B, MATLAB's environment may dynamically choose to swap subsets in and out of main memory or cache at will. Thus, there is a "non-deterministic" aspect to the MATLAB execution pathway (rather, this nondeterminism is really just "beyond the application programmer's control", though totally deterministic to the systems engineer) runtime. As a general rule, by allowing straightforward programming statements (such as "A+B"), even if those matrices were each several gigabytes in size, MATLAB allows the programmer to unwittingly request enormous volumes of computation without really realizing it. So, it breeds a style of programming which is not cognizant of performance and machine limitations. This is either "a wonderful evolution towards higher level abstraction" or a "blight afflicting an entire generation who don't know C++, FORTRAN, and DEC assembler language" depending on your interpretation.

In summary, MATLAB is not inherently slower than C++, it is not inherently better or easier. Both languages provide different feature sets and different paradigms for interacting with the hardware. If your advisor or research group uses C++ exclusively, it is a cultural preference, rather than a legitimate scientifically grounded analysis based in performance metrics. However, from experience, explaining the details of 2009-computer-hardware-and-software-architecture is rarely effective at uprooting decades of tradition. Certain research communities use FORTRAN. Certain programming teams use g++. Certain teams are dynamic and switch languages at will, based on best tool for a particular task. You may have to learn C++ (which is a worthwhile use of your time), simply to satisfy your professor; and it is very possible that the extra knowledge you gain from this learning experience will make you a better, more hardware-aware programmer. That will likely improve your code performance. Nimur (talk) 15:17, 18 September 2009 (UTC)

It's important to note that when comparing the performance of languages which do not have a "canonical" implementation, you are really comparing the performance of particular implementations of those languages. C++ is defined in terms of a theoretical "abstract machine", and very little information about performance can be inferred from its definition, except that the time complexity of certain standard library operations and algorithms is specified. Given a well-formed C++ program, the C++ standard places no requirements on the executable produced by a compiler, except that it shall exhibit the same observable behaviour as if the program exactly followed a valid execution sequence of the theoretical abstract machine. For example, if one were to write a program that calculates all the prime numbers between 10,006,721 and 0 and prints the lowest, the compiler is free to generate machine code that is equivalent to simply

#include <iostream>
int main() { std::cout << "2\n"; }

My conclusion is similar to that of Nimur:The only way to determine which of two languages is faster, for a given implementation of those languages, is comparative benchmarking. decltype (talk) 17:01, 18 September 2009 (UTC)

Apart from being slow, Matlab is a memory-hog. It amazes me that is manages to run out of memory on a 2GB machine when asked to do a few manipulations with vectors of ~1 million entries. You said your mesh will have that number of entries, in my experience Matlab is a no-go for large scale application.195.128.250.184 (talk) 21:22, 18 September 2009 (UTC)

As I discussed above, MATLAB's syntax allows for much behind-the-scene implicit computation and storage. If you are using excess memory by a factor of 1,000, you are probably storing more than you realize - multiple copies of your million-element array. You might take a look at Mathworks' Memory Managemeny Guide or consider taking one of the free MATLAB courses which are offered to train on how to use MATLAB. A MATLAB array uses exactly the size of the native element array, plus about 60 bytes of overhead for name, length, and dimensionality; if you are finding order-of-magnitude deviation from this, it is because you are doing something else (like copying the array many times, or failing to perform in-place calculation); or you are using cell-arrays instead of true-arrays. These are the same issues you would run into with a FORTRAN array, C++ array, or any other programming language if you performed equivalent calculations. It sounds like you are unaware of how many copies of that million-element array you have actually created. Consider learning the following MATLAB commands:

who
whos
feature('memstats')

As a programmer, only you can be held accountable for understanding the language's memory-management system; ignorance of dynamic memory management is not a justification for blaming the language's performance. Nimur (talk) 16:13, 19 September 2009 (UTC)

Unless they are the languages built-in functions that are not doing their work properly. It hasn't been noted that a good C++ program will be faster than matlab because much more time is devoted the development of C++ compilers than matlab. C++ certainly has more flexible and efficient data structures. Thinking about your program and making an "optimal" design rather than putting together something that works quite well might be a good thing in the supervisor's eyes. --194.197.235.240 (talk) 00:22, 20 September 2009 (UTC)

Forgive me for my loud personal opinions, but I strongly disagree with your assertions: more time was devoted to the C++ compiler than to MATLAB? Do you have a source for that? MATLAB has been in continuous development for decades - longer than C++, actually. By the time C++ was conceived, let alone implemented, MATLAB was already a mainstream commercial product available on several architectures and operating systems. Significant work has been done to optimize MATLAB's runtime - for example, automatic copy-on-modify, a feature that (to my knowledge) exists in no commercial or free C++ toolkit, that can reduce memory copy times by orders of magnitude. "Flexible and efficient data structures" begs for a definition of "flexible" and "efficient" - again, I point to MATLAB's ease of portability, compared to C++, as an example of "flexibility". As far as efficiency, again we must revert to the side-by-side benchmarking for a specific feature. I'm a happy C++ and FORTRAN-90 programmer, and I recognize the desire to stick to "native compiled code", but seriously - the vast majority of complaints levied against interpreted languages are buried in fiction. Perhaps you would like to run the benchmarks yourself? You might find that empirical data contradicts "intuitive" preconceptions about "compiled"-vs.-"interpreted" languages. A modern operating system provides so many degrees of separation from the bare metal, anyway - system interrupts, software trap vectors, emulated processors, non-native machine instruction handling, dynamic runtime compiling, fat binaries, virtual memory and paging management - that the notion of "compiled program" is really an antiquated idea. (Try linking without the system library, if you don't believe me! You may seize up at your first "printf"). Unless you run without an operating system, you should be very wary of any claims about programs that run on "raw hardware" because they are "compiled" as opposed to "interpreted." You might find that writing C++ that can actually run on a high-performance Nehalem (without a Linux or a Unix or a Windows Vista to help you stagger along in the platform-specific darkness) is not so very easy after all! But of course, by reputation, we grant C++ and FORTRAN a special place as "native code" because that's historically what they have always been called; and Java and MATLAB are "interpreted". Empirical comparisons are rarely considered when indoctrinating students to prefer one programming methodology over another. I say again - for a specific problem, the only real, relevant benchmark is a side-by-side comparison of equivalent implementations. Nimur (talk) 20:59, 20 September 2009 (UTC)

Appscene

Does anybody know how to download apps from appscene.org? I had some trouble locating a place that will let me browse and download apps.

--Dudforreal (talk) 13:58, 18 September 2009 (UTC)

Contributors sued, assaulted?

Have contributors been sued, or physically assaulted? Perhaps this is not the right place to ask, but I have some concerns about possible retribution, if I were to contribute to certain articles, which I have not done. --DThomsen8 (talk) 15:42, 18 September 2009 (UTC)

People or wikipedia have been sued (or threatened with legal proceedings) in the cases where incorrect (and personally offensive) biographical information has been posted see WP:BIOG for guidelines.

As for physical assault, I'm not aware of this. Excluding the possibility that you live in a heavily censored country where internet activity is monitored and human rights not respected in terms of free speech, etc...

Where you thinking of something in particular? a particular article or set of articles?? Why do you have this concern?83.100.251.196 (talk) 16:01, 18 September 2009 (UTC)

(ec) As far as I'm aware, there haven't been any major newsworthy incidents of wikipedia-based retribution against editors in the form of "assault". That being said, you should not use any Wikimedia projects to break any laws or to commit libel. Wikipedia has policies to preclude you from committing libel; and Wikipedia must comply with the laws (particularly those of the United States), which may involve releasing information to investigators. If you feel that your contribution is important, but must be contributed anonymously to avoid retribution, you might want to read about Wikileaks (an unaffiliated project that is not part of the Wikimedia Foundation or Wikipedia). This will allow you to post sensitive information you have come across while remaining "more" anonymous. However, you should be aware that with sufficient effort, it may still be possible for somebody to locate you. Given your earlier question on the Village Pump, I strongly recommend you read our policies about biographies of living people. This is one of the most strictly enforced policies, as the people who run Wikipedia do not want to propagate libelous material. If you are unsure of the legal implications of your contributions, or the possible ramifications, you need to contact an attorney in your area, because we can not give you legal advice. Nimur (talk) 16:06, 18 September 2009 (UTC)

Probably Wikipedia:Help desk would be better, It is allowed to have a second account to protect your identity in a particular area but you need to be very careful not to mix the two in the same area or use an ip instead. See WP:SOCK#LEGIT Dmcq (talk) 16:16, 18 September 2009 (UTC)

Check Wikipedia:Wikipedia as a court source. ---— Gadget850 (Ed) ^talk 16:39, 18 September 2009 (UTC)

one of the wikipedia admins, i think allison or something, was actually stalked for a while. then the guy was imprisoned. not much information on it though, i think the oversighters have been at work

Problem sending e-mails after Verizon blocked port 25

Maybe there is someone out there who had and solved the same problem? Verizon recently blocked port 25 for outgoing mail and advised customers to change it to port 587 (for outgoing mail). Unfortunately this doesn't seem to work for me after trying with several e-mail clients I have in use. Receiving e-mails works just fine on port 110 but what can I do to be able to send mail again? Help is much appreciated. Thanks, The Magnificent Clean-keeper (talk) 16:33, 18 September 2009 (UTC)

PS: Verizon's customer service isn't very helpful and I'm kinda tired of being placed on hold etc. The Magnificent Clean-keeper (talk) 16:33, 18 September 2009 (UTC)

Could you explain with as many details as possible what happens when you do try port 587 outgoing? (I had to switch from 25 to 26 when my ISP did a similar thing. Outlook was unperturbed, AFAIK.) Comet Tuttle (talk) 16:44, 18 September 2009 (UTC)

Sure. With "mailwasher pro" I get this error message: Connection timed out (possibly caused by a firewall) while with "Outlook Express" I get: The connection to the server has failed. Account:'[my e-mail here]', Server:'[my server detail here]', Protocol: SMTP, Port: 587, Secure(SSL): No, Socket Error: 10060, Error Number: Ox800CCC0E. While trying, I had only Windows XP's (SP 2) and the Verizon's router firewall enabled as I usually have. BTW, I've also tried now port 26 but without success. If you need more info let me know which and I'll check on it. Thanks for looking into this :) The Magnificent Clean-keeper (talk) 17:18, 18 September 2009 (UTC)

The obvious question that comes to my mind: does your SMTP server actually listen on port 26, 587, or any other port? It sounds like your ISP blocked that port; but your SMTP server has not changed its policy. One possible solution is switching to secure authentication (e.g. SSL or TLS authentication). There may be a configuration setting. You have not told us who operates your SMTP server, but I'm going to guess (a) it is a third-party, not Verizon; and (b) Verizon probably offers its own SMTP server, which you can switch to and use. Most likely, they have changed their configuration to match their new firewall setting, and expect you to use their SMTP server. Nimur (talk) 17:40, 18 September 2009 (UTC)

I was just about to paste the following when I saw your reply: Forgot to mention that I rarely use my Verizon e-mail address so I just checked it and it's still working just fine on port 25. So my problem is just with my non-Verizon accounts. Let me check on authentication again although I'm sure it's set correcly (since my 3rd party e-mail provider requires it).The Magnificent Clean-keeper (talk) 17:55, 18 September 2009 (UTC)

Nope, doesn't work. Authentication is set and I tried with SSL - no difference :( . Any way I can check if my SMTP is actually listening?The Magnificent Clean-keeper (talk) 18:03, 18 September 2009 (UTC)

• Well well, I just tried bouncing some spam from my 3rd party accounts by using Verizon as SMTP and guess what? It doesn't let me because VERIZON refused to send spam. Could it be that Verizon blocked outgoing mail from my other accounts? That would be quite, well you know what I'm trying to say. "Anger is building up".--The Magnificent Clean-keeper (talk) 18:26, 18 September 2009 (UTC)

Yes, Verizon is blocking email relaying, so in order to use their SMTP server, you have to be coming from a Verizon email account. Don't get mad at them for that, if everybody did this it would cut down on spam tremendously. As for your non-verizon accounts, unless they are set up to listen on 587, then you've got no other way to connect to them if VZ is blocking 25. You could try contacting those server providers/owners to see if they can enable 587, otherwise you're kind of stuck. Arakunem^Talk 19:03, 18 September 2009 (UTC)

Yes, the latter response is probably the reason that I had to come here to get it figured out since Verizon doesn't bother to fully inform their customers. Not the first time and not the last.... so I'm still mad at them and will be :P

Anyhow, big thanks to you all for helping me out. Cheers, The Magnificent Clean-keeper (talk) 19:29, 18 September 2009 (UTC)

This is standard for many ISPs. You can collect mail from just about any account on any port - that is fine. You can send mail through their service using your account with them and that's it. For example, my ISP only allows outgoing mail to go through their mail server. So, for my personal email, I check it on my own server. For my student email, I check it on my university account. For my work email, I check it with my work account. When I send mail - no matter which account I have in the "from" field, it is sent through my ISPs mail server. The recipient doesn't know this. They see the from as being from my personal, student, or work account. Only by looking at the email headers will they notice that the actual server doesn't match the email address. -- kainaw™ 05:57, 19 September 2009 (UTC)

Kainaw's description is the "proper" way to use the SMTP server - even if you have multiple email accounts. It's rare to expect that the SMTP server should necessarily match the from: or reply-to: address. The Verizon server should permit you to use its service because you are on a Verizon IP (with or without authentication, based on their policy). Alternatively, you need to authenticate to a third-party SMTP server; this really should be done with SSL to prevent plain-text transmission of your password, etc. The main idea is to separate the processes of outgoing- and incoming- emails. Outgoing mails can be sent from anywhere (like dropping a properly stamped letter in any mailbox) - you are not required to use a particular mailbox for outgoing email. But, to prevent spammer-abuse, most SMTP servers limit who can connect. So, use the Verizon-provided server, even for your non-Verizon email accounts, because it has been specifically configured/firewalled to allow you to use it. Nimur (talk) 06:25, 19 September 2009 (UTC)

4 gb ram but showing 3 gb ram

Hello there I have just upgraded my ram to 4 gb. But it's showing only 3 gb. I am using XP SP2 32 bit.Is it faulty ram--119.30.36.40 (talk) 18:28, 18 September 2009 (UTC)

Due to an architectural decision made long ago, if you have 4GB of physical RAM installed, Windows is only able to report a portion of the physical 4GB of RAM (ranges from ~2.75GB to 3.5GB depending on the devices installed, motherboard's chipset & BIOS). From [2] Taggart.BBS (talk) 18:45, 18 September 2009 (UTC)

To remedy this, you can install a 64-bit OS such as Vista 64-bit or Windows 7 b4-bit IF your processor is compatible. If you have a core 2 duo, core 2 quad, an Athlon X2 or other AMD series that's fairly recent or any modern processor you should be able to install a 64-bit OS and take advantage of that extra RAM. Unfortunately this is the only step you can take, and if the processor itself is only 32-bit, you can't even install a 64-bit OS, so you will need to upgrade your hardware. Make sure you look up the exact processor model if it's a Pentium 4, Pentium D, or Celeron to determine if it's 64-bit compatible! Caltsar (talk) 19:39, 18 September 2009 (UTC)

Or the 64-bit version of Windows XP, presumably. Comet Tuttle (talk) 21:27, 18 September 2009 (UTC)

Athlon 64, the first x64 processor, has been out for half a decade now. You don't need a bleeding edge CPU to run a 64-bit OS (and there are some notable recent exceptions, such as Core 1's and Atoms) --antilived^{T | C | G} 03:57, 19 September 2009 (UTC)

Compatible Board(s) for Processor "Q9400"

Hello there, I want to upgrade my mobo to Intel motherboard. I have Core 2 Quad processor which FSB is 1333 MHz. But 3 boards listed in extreme series in intel website are FSB 1600 MHz supported. Will my processor run properly on them? I am bit confused about them.--119.30.36.39 (talk) 19:17, 18 September 2009 (UTC)

If you look on your favorite tech shopping site many motherboards are listed with multiple FSB compatible speeds. In general, you should be able to use a board with a higher FSB listed than your processor has and it will clock down to 1333Mhz to work with your processor. The Intel site is a bit confusing in this regard, but many motherboards will list multiple frequencies in the specs (such as 1600/1333Mhz). Caltsar (talk) 19:34, 18 September 2009 (UTC)

If you open the link you gave, click on a motherboard, you should get somewhere like here [3]

Then click on "compatability", then "supported processors" which should take you to a page like this [4]

This gives a list of compatable processors - as you can see there are various types of core 2 quads with 1333MHz FSB - you need the type eg Q8200 etc.

If it's not on the list it's not supported.

In general there wont be a problem with a 1333Mhz FSB, but you should check first.83.100.251.196 (talk) 21:30, 18 September 2009 (UTC)

Diagrams on TCP/IP and IMPs/TIPs

I am in the final stages of writing a commissioned, non-technical book about the internet and have had 4 diagrams created for the internet history chapter to help explain 'Hub and spoke', 'network', TCP/IP and IMPs/TIPs. These diagrams are to my brief and before I set them in stone I'd like to show them to someone who understands the engineering/computing side. The book as a whole is social-cultural and that's my overall background.

This is also my first time on Wikipedia and I can't seem to upload the .pdf files for you to have a look at, but I have 4 .pdf files which have 'artwork'/B&W line images created specially for me to my brief for this purpose.

Paddy's GirlPaddy's Girl (talk) 19:42, 18 September 2009 (UTC)

You can only upload content to Wikipedia under a free license so anyone can re-use it (including commercial use); or under fair use to illustrate in an article. --h2g2bob (talk) 20:12, 18 September 2009 (UTC)

However, if you host your files on an external site (something like freepdfhosting.com), you can post the links to your files here, and we can take a look at them that way. Indeterminate (talk) 03:52, 19 September 2009 (UTC)

Geejo strikes again!

If you go here [5], this shows what happened to a Yahoo email I was working on. I hadn't touched it for two hours. Yahoo now saves drafts automatically, so I didn't lose anything.

When I started to add something to the email, this is what the cursor did. Then the screen got foggy. Then most of what was on the screen disappeared and at the top it said, "Not responding".

And now the rectangles at the bottom of the screen have switched places. I'm able to do everything fine here. It's just there.Vchimpanzee · talk · contributions · 20:29, 18 September 2009 (UTC)

Wait, now the screen is back but it's much smaller and the "Not responding" message is still there.Vchimpanzee · talk · contributions · 20:31, 18 September 2009 (UTC)

Weird. The border of the screen with the problem appeared, with a foggy image of the top, on top of what I was doing, and when I scrolled down, what was in the area inside the borer didn't scroll.Vchimpanzee · talk · contributions · 20:37, 18 September 2009 (UTC)

Now the text and everything are extremely large, although the screen is small.Vchimpanzee · talk · contributions · 20:39, 18 September 2009 (UTC)

I tried clicking on the red X and it gave me the choice of restarting or closing. I tried restarting. That small screen is still there, but it's black and I can't do anything to it.Vchimpanzee · talk · contributions · 20:42, 18 September 2009 (UTC)

Restarting the computer has solved the problem. I'd still like to know what happened. The information about my computer is on here somewhere.Vchimpanzee · talk · contributions · 20:51, 18 September 2009 (UTC)

1. When your computer's mouse cursor changes into a spinning wheel or an hourglass, this is the "wait..." cursor. This usually happens (a) when the application that "owns" the window (the one that your mouse cursor is currently over) has told Windows to display the "wait..." cursor; it can also happen if (b) the application stalls and is not responding to Windows's queries; or (c) if a humorist like Geejo creates a "mouseover" effect causing this.

2. In your 2nd paragraph, above, you got the "wait..." cursor and then a "not responding" message because of 1(b) in the above paragraph.

3. Have you tried the previous suggestion of adding RAM to the computer? I think you are using a computer that is old and needs more RAM, and probably a hard disk wipe. Comet Tuttle (talk) 21:26, 18 September 2009 (UTC)

I don't need to add RAM. It's only a year old. If I could figure out where my computer information was, I'd put it here. It's somewhere in the reference desk archives now.Vchimpanzee · talk · contributions · 18:25, 19 September 2009 (UTC)

Yahoo textareas are sensitive to time-outs. If you leave something open but untouched for a while, you are better off closing that page/tab and re-opening it from the Drafts folder. If a reply or forwarding fails to work, same thing...save it as a draft, open it from that folder and send it immediately. Once a mail page goes "not responding" it never will, so close it and open a new one. - KoolerStill (talk) 16:52, 20 September 2009 (UTC)

Downloading fonts

When I go to a free font website, I can find fonts I like, and when I download the fonts, I get a .ttf file. Do I need to do something further to make these fonts accessible to programs like Word, or is that all that I need to do? Who then was a gentleman? (talk) 22:13, 18 September 2009 (UTC)

Quit Word, then go to Control Panel -> Fonts and drag the .ttf file into the resulting window. Upon launching Word, the new font will be available. Comet Tuttle (talk) 22:54, 18 September 2009 (UTC)

Drag it from where? When I go to the page where the .ttf file is, in another Window, and try to drag it into the Control Panel pane, it doesn't work. And the files are located in C:\Documents and Settings\Compaq_Administrator\Local Settings, which is not accessible from the Control Panel. Who then was a gentleman? (talk) 23:03, 18 September 2009 (UTC)

What OS version? If you're using Windows XP, try Control Panel -> Fonts and then look in the File menu of the Fonts window for "Install New Font...". You may have to be logged in with an account that has administrator rights; I'm unsure on that point. Comet Tuttle (talk) 23:18, 18 September 2009 (UTC)

Download them to your desktop (you can put them anywhere you want, but I find having them on my desktop is 'tidier'). Assuming you're using Windows, click on Control Panel, open Appearance and Themes and click Fonts. Then click 'File', 'Install New Font' and under 'Folders' click 'Documents and Settings' and choose your username and 'Desktop'. The font(s) will then appear and you can click 'OK' and it will upload them to the font list. If you have a program that uses fonts open when you do this, you'll have to restart the program before the font can be used. HalfShadow 23:31, 18 September 2009 (UTC)

Great, getting them to the desktop worked. Thanks. Who then was a gentleman? (talk) 00:07, 19 September 2009 (UTC)

September 19

Hacking a registry that isn't running

Resolved

It's a long story, but the short version is that I have a hard-drive with a full, legal installation of Windows XP. The computer it once was in has died. The computer case which once had the registration key is long since gone to the dump. Yeah, dumb. There are plenty of free programs out there that will hack your registry and provide you with all kinds of serial numbers of stuff you've installed, but they all search the active registry, not the one sitting inert on a harddrive. Do any programs exist that will do this? And before you ask, yes, I've tried simply installing the drive and booting from it, but the computer configuration is just too different and I get stuck in a boot loop. Any help? I'm waiting to hear back from the company I bought the computer from to see if they've kept a record (Microsoft suggests I do that before contacting them), but I'd like to get back-up plans in place, if I can. Matt Deres (talk) 01:37, 19 September 2009 (UTC)

You might be able to do it by importing the hives. Ie on the machine that is running, import the file from the drive of the machine that won't boot, edit, then export. I have used File, Load Hive to edit another user's registry (on the same PC) before, but that only appears to allow loading of the user hives, not system hives. However File, Import might help - but I've never tried it. Obviously, this has the potential to clobber the registry on the running PC, so try it at your own risk, after taking appropriate precautions. Mitch Ames (talk) 03:38, 19 September 2009 (UTC)

Yikes. That's just friggin' scary. Besides the basic risks involved, the only completely working version of Windows I have now is Vista anyway; I don't fancy trying to import the XP registry into Vista. :) Matt Deres (talk) 11:53, 19 September 2009 (UTC)

You don't import the hive, you just mount it on an unused key. It's like mounting a filesystem on an empty subdirectory in Unix. You don't need to do this, though—use MJB Keyfinder instead (see below). -- BenRG (talk) 23:03, 19 September 2009 (UTC)

I don't know what you need to do with the registry, but for plain editing you might try the Offline NT Password & Registry Editor. --164.67.235.138 (talk) 04:09, 19 September 2009 (UTC)

That site is for recovering passwords; I need to find the 25-digit security key for XP to install. I need something that will provide me with that key; there are plenty of programs that can hack the registry and do that for a running copy of Windows; I just want one that can extract it from a dormant hard-drive. Matt Deres (talk) 11:50, 19 September 2009 (UTC)

You might consider talking to Microsoft on the phone before going to this much trouble, unless you have tried already. If you have any documentation at all, pull it together and find out what they say. At worst, they might provide a new set of disks for some amount of money, hopefully less than the full cost of XP. New copies of XP that appear legit can be bought on Ebay for as little as $60. EdJohnston (talk) 15:49, 19 September 2009 (UTC)

That's my escape plan, if necessary, but online guides I've read have suggested that OEM versions of Windows (even ones like mine that indeed are simply Windows and not Windows + whatever crap HP or whoever feels like squeezing onto a "system restore" disc) are not as easy to get keys for. According to the About.com page, for example, they say getting a regular Windows key costs $10 + time spent on the help line (which is not free), but that OEMs are just more complicated than that. It remains an option. Matt Deres (talk) 16:07, 19 September 2009 (UTC)

Magical Jelly Bean Keyfinder works with hive files from unbootable Windows installations. It's free and open source. -- BenRG (talk) 23:03, 19 September 2009 (UTC)

You are my GOD! Thank you very much - that did the trick. For the record, you do need to be either logged in as the administrator or "run as administrator" to get the hive to load. Unhelpfully, the program doesn't tell you what the problem is, it just says that the load didn't work. Many thanks again! Matt Deres (talk) 21:09, 20 September 2009 (UTC)

BIOS password

A long time back (about three years or so), when I didn’t know anything about BIOS and stuff, I set the BIOS password not knowing what I was doing. Now, I’ve forgotten the password, but need to enter BIOS to change a few settings. Is there any way in which I can recover or reset my password? Please help! 117.194.232.75 (talk) 09:18, 19 September 2009 (UTC)

You can reset your BIOS settings by unplugging it from mains and taking out the battery on the motherboard for 30 seconds. --antilived^{T | C | G} 11:21, 19 September 2009 (UTC)

I also believed that worked a few months ago, but now I know that you sometimes need to remove the battery for several minutes (try 15). --Andreas Rejbrand (talk) 12:12, 19 September 2009 (UTC)

Some motherboards have a jumper that resets the password, without taking out the battery or resetting CMOS. --164.67.235.138 (talk) 19:17, 19 September 2009 (UTC)

Yea most motherboard have that, but it's a lot easier to tell a user to remove a big shiny silver thing than to fiddle with jumpers. --antilived^{T | C | G} 03:56, 20 September 2009 (UTC)

No. of notebooks in Pakistan (How Many?)

How many people in Pakistan have and/or using notebooks and laptops? What is the market size and growth potential?116.0.61.115 (talk) 09:37, 19 September 2009 (UTC)

I can't find any data for pakistan, though there are some numbers available for india (not complete). Would assuming the same ownership per capita be reasonable - you could derive a very rough figure?83.100.251.196 (talk) 12:47, 19 September 2009 (UTC)

Tiled images

Hi! I am looking for help with these question (especially the first). bamse (talk) 11:54, 19 September 2009 (UTC)

In that case, the images appear to be in a simple x,y format (e.g. [6] = x02, y14). The minimum (top left) is 1,1; the maximum is 28,19, at the maximum zoom, 4). You'd need to use a tool that let you specify the maximum x or y images and download them to a big folder (basically any language can do this pretty easily). Then, more complicatedly, you'd need something that could stitch those together based on their coordinates (ImageMagick+whatever language you originally used, is probably best for this). I'm not sure there's a one-stop-shop program that will do all of those automatically. --98.217.14.211 (talk) 13:30, 19 September 2009 (UTC)

Thanks for the reply. I was mainly interested in the first part, getting the tiles on my computer. Is there a tool that can do that, or would I have to code something myself? Stitching is not a problem and it seems to work. bamse (talk) 14:11, 19 September 2009 (UTC)

I gave into the temptation and wrote a PHP script - see my reply at the Graphic Lab question. (Never sure of cross-posting etiquette, but it seems to be the more specific channel) - IMSoP (talk) 14:59, 19 September 2009 (UTC)

Pingler

What is Pingler for? Apparently it's got something to do with blogs but the site itself doesn't explain much? Help appreciated. Cheers, Jeffrey Mall (talk • contribs) - 14:44, 19 September 2009 (UTC)

It tells search engines that your blog has been updated, so then any new content you added is indexed faster. Xenon54 / talk / 14:48, 19 September 2009 (UTC)

Ahh thank you! Jeffrey Mall (talk • contribs) - 14:49, 19 September 2009 (UTC)

Actually I don't think it "tells" search engines anything. I believe they simply perform ping, which is a network diagnostic tool (which you can run for yourself, for free). I'd call this a "scam site"; it looks like they want to charge you for a service which has no impact on your search-engine ranking. Nimur (talk) 16:19, 19 September 2009 (UTC)

(Twitter agrees, and has suspended their account for suspicious activity... sounds like spamming! Nimur (talk) 16:20, 19 September 2009 (UTC)

Hmm.. Jeffrey Mall (talk • contribs) - 17:06, 19 September 2009 (UTC)

Algorithmn to space cars along road segments?

I'm trying to write an algorithmn that will space static cars (just points or dots really) evenly along a road. The road consists of a number of straight-line road-segments that join up to make the road. For simplicity I am first of all trying to write an algorithmn that can do this for a one-dimensional road, and then hopefully modifying it to deal with a more realistic two-dimensional road. Even when the road goes around a bend, I want the cars spaced at every X metres along the length of the road. I'm stuck trying to create an algorithmn that can cope with all circumstances: for example where the road-segment lengths are less than the distance between cars.

Is there any forum where I could get help creating such as algorithmn please? 89.243.181.104 (talk) 16:28, 19 September 2009 (UTC)

You can ask here - as far as I can tell this is easy:

1. Sum the length of the road segments to get the road length.

2. Divide the total road length by the number of cars to get the spacing between cars.

3. Starting at the first road segment add the road segments until the length is greater than the car spacing.

4. At this point place a car at the point on that segment where the distance from the previous car is correct. Then start counting the distance again from that point. Repeat the process from this point until you run out of cars.

Did that makes sense? Ask about any part you get stuck on.83.100.251.196 (talk) 17:07, 19 September 2009 (UTC)

Good, thanks, I had begun thinking along those lines myself, but what about when the segment is much longer than the car-gap? Or where you have segments of various lengths which may be much longer or much shorter than the gap? I'm trying to think what variables you would need to keep and update. 78.144.252.66 (talk) 19:01, 19 September 2009 (UTC)

You need to count the number of segments that have already been used, and also the position along the segment the last point was placed.

A general proceedure would be to first check if the point can fit into the current segment, and if so do so, and update the most recent point

and if not then to increment the segment number (remembering compute the increment or decrement of gap length by the correct ammount).

It might be easier to show some pseudocode - here one that finds the segment, and possition along the segment of the Qth point. If you use this as a proceedure you could just call it for each position - it's not the most efficient way - but should always work.

Note that l[n] is the length of the nth segment - an array - so here you can vary the segment length if you want.

n=number of segments
p=number of points
l[n]=length of segment n
Lengthtotal=sum (1 to n) of l[n] self explanatory
pointseparation = Lengthtotal/p

computer Qth point distance
distancetopointnumberQ=Q*pointseparation

x=1    x counts the number of segments
while ( l[x]<distancetopointnumberQ ) do
  {x=x+1 
   distancetopointnumberQ=distancetopointnumberQ-l[x] }
  
Output "Qth point on segment ",x," distance along that segment=",distancetopointnumberQ 
stop or return 

Note I've let the points go right to the end of the line, and there is no point at the beginning (technically this would be the 0th point) - to change this behaviour minor tweeks are needed

Hopefully I haven't made some blindingly obvious algorhtylmic error...83.100.251.196 (talk) 20:55, 19 September 2009 (UTC)

Thanks, I've studied the above. I think - could be wrong - that it would only work where the road-segment-length is much less than the distance between the cars. It does not have any mechanism for placing several cars within a long length of road-segment. Having such a mechanism would also entail remembering how much of the road segment was left over since the last car, and taking that into account when positioning the next car (which might be in the next road-segment, or could be several road-segments further on). 78.149.186.66 (talk) 19:39, 20 September 2009 (UTC)

Facebook moble texts

i just added someone as a friend, and asked facebook for the sms mobile text sevice with them, so why isnt it sending me mobile texts about their updates?Accdude92 (talk) (sign) 17:09, 19 September 2009 (UTC)

There are several answers to this question...you need to give us more details. Does it work for other people? Is this the first person for which you have subscribed to SMS updates? Have you set the notifications up correctly (correct carrier, phone number, etc.)? Xenon54 / talk / 18:05, 19 September 2009 (UTC)

Does it work for other people?

Yes

Is this the first person for which you have subscribed to SMS updates?

No

Have you set the notifications up correctly (correct carrier, phone number, etc.)?

Yes

Accdude92 (talk) (sign) 18:25, 19 September 2009 (UTC)

So it is evident that the problem is only with this one particular person. Perhaps the addition of the person to your notification list "didn't take" yet (so wait for another status update, then report back here if the problem continues). If what you're telling us is correct, then there is probably nothing wrong on your end. Xenon54 / talk / 18:58, 19 September 2009 (UTC)

Ship of Theseus

Is there any consensus on how to determine the age of a desktop computer in which, as with the Ship of Theseus, every component has been replaced on a separate occasion? NeonMerlin[7] 19:15, 19 September 2009 (UTC)

No, just as there isn't with the Ship of Theseus. It doesn't matter whether its a desktop computer an automobile, it's a philosophical question, not a technical one. --98.217.14.211 (talk) 21:53, 19 September 2009 (UTC)

One clue is to look for the oldest files on the system. Though on my desk top computer, the files go back to 1980, they are more of a reincarnation from an old Apple II pascal disk I had. Graeme Bartlett (talk) 22:11, 19 September 2009 (UTC)

Right, file creation dates have nothing to do with the age of the machine they are on at all, unless you can prove they were created by that individual machine. Even then, it doesn't really solve the Theseus problem, unless you are just interested in, "when was the oldest hardware component of this machine put together," but that's not the Theseus problem (which is a question of identity, not a simply question of forensics). --98.217.14.211 (talk) 03:20, 20 September 2009 (UTC)

"Beep" command makes my computer case beep!

I've got Windows XP and I've downloaded the GWBasic interpreter onto my desktop, where it runs in a DOS window very well. When I put my headphones on and typed the beep command, the beep noise came from the case of my tower PC, not the headphones. What is it in the case that is beeping? Could I use it for other sounds too? 78.144.252.66 (talk) 19:21, 19 September 2009 (UTC)

Have a look at PC speaker. Old DOS PC games (e.g. Doom) usually had an option to play the sound effects/music through it in the setup program. It sounded, as you might imagine, all bleepy. --Kurt Shaped Box (talk) 19:26, 19 September 2009 (UTC)

If you use DOSBox, you can redirect the beeps to your headphones. NeonMerlin[8] 19:40, 19 September 2009 (UTC)

Oh my gawrsh, this question makes me feel old. :-( --98.217.14.211 (talk) 21:57, 19 September 2009 (UTC)

Any Windows programmer can use the computer's speaker to produce a sine tone. The function beep in Windows API (kernel32.dll) can be used for this:

beep(400, 500)

will use the computer's speaker to produce a 400 Hz sine tone for 500 milliseconds (that is, 1/2 second). --Andreas Rejbrand (talk) 12:41, 20 September 2009 (UTC)

September 20

Visual basic express edition coundown program

My friend is making a countdown for me in visual basic, so how would he make the countdown work when the computer is off?Accdude92 (talk) (sign) 01:43, 20 September 2009 (UTC)

And btw, I would like the countdown to NOT use the internet in any way.Accdude92 (talk) (sign) 01:48, 20 September 2009 (UTC)

You'll have to check the system time, save the end time to a file, and have the program check the file against the system time on startup. NeonMerlin[9] 02:18, 20 September 2009 (UTC)

But he dosn't don't know how to compare that to the text and update it.Accdude92 (talk) (sign) 02:25, 20 September 2009 (UTC)

It sounds like you friend needs a VB crash course! He'll have to read KB304427, which deals with read and write operations (plus some others). Xenon54 / talk / 02:33, 20 September 2009 (UTC)

Problem with external hard drive

I have a Hitachi Easy Drive that I've been using with my MacBook. Now I want to use it with a PC (running Windows XP) to transfer some files, but when I plug it in and turn it on, it doesn't appear anywhere. There's a little icon on the task bar to safely remove the external hardware, but it doesn't show up as an available drive. I've tried using the "add hardware" button in the Control Panel, but when I try to add the external hard drive, it says, "Windows cannot use this hardware device because it has been prepared for "safe removal", but it has not been removed from the computer. (Code 47) To fix this problem, unplug this device from your computer and then plug it in again." I do so, and no luck. What do I need to do? --68.239.11.74 (talk) 02:16, 20 September 2009 (UTC)

It's plausible that the hard drive is formatted as HFS Plus, which cannot be natively read by Windows. The linked article contains links to software that enables Windows to read those hard drives. Xenon54 / talk / 02:40, 20 September 2009 (UTC)

Interet keeps crashing...

Why does my wireless internet keep crashing?Accdude92 (talk) (sign) 03:26, 20 September 2009 (UTC)

If you want a serious answer, you must provide a lot more information. What kind of wireless? What kind of computer? What operating system? What do you mean by "crashing"? If you just want people to poke fun at your inability to provide even the slightest hint of information required to answer your question, then leave it be for a few hours and the jokesters will be here shortly. -- kainaw™ 03:39, 20 September 2009 (UTC)

What kind of wireless?

WiFi, I have a router, and a usb stick to get the signal

What kind of computer?

Compaq Presairo SR1150NX

What operating system?

Windows XP home edition

What do you mean by "crashing"?

It just randomly disconnects. Like I am typing on here and it randomly stops sending me data. Oddly, the icon says its still connected...

Accdude92 (talk) (sign) 03:46, 20 September 2009 (UTC)

Sounds like a problem I had with one of my computers...but that was under Ubuntu. I fixed it by taking out the stick and then plugging it back in, and then restarting the computer if that didn't work. (That was 2 years ago. It's much more stable now.) But, as Kainaw said, you really need to work on providing more information - we're not mindreaders. If you want this problem to really be fixed, you still need to tell us the manufacturer and model number of your stick. Also, go into Device Manager (Start -> Run -> devmgmt.msc) and check and see if the device is listed, and then see if it lists any errors. Errors are indicated by a small ! in a yellow circle on top of the device's icon. Posting at least the OS and specifics about the problem is a must for any question (and with the amount of similarly-worded questions you post on here, I'm surprised you haven't learned that yet). Xenon54 / talk / 12:03, 20 September 2009 (UTC)

Java hacking book?

Anyone got a favorite book about how to hack Java code? I.e. not a book about the Java language itself (I've programmed enough other languages that Java is pretty straightforward), but about how to use the surrounding infrastructure, libraries, tools, etc. My immediate task is to add some features to a big existing Java program, and in order to do that I want to run it under a debugger (Netbeans or Eclipse) to see what it's doing. And in order to do that (per the Netbeans docs) I have to modify the Ant build.xml to include a debugging flag for javac, so I'm off to look at the Ant docs for how to do that, and then I have to get all the code (currently spread across dozens of directories and several library jars that I also want to debug through) loaded into Netbeans, etc. You get the idea, there's just this ton of stuff to get on top of before reaching the equivalent of "hello world".

Is there a short cut through all this? Is there a particular book or url that I should look at? Thanks. 70.90.174.101 (talk) 07:19, 20 September 2009 (UTC)

Java class files can usually be easily decompiled. Decompilers include JAD, JODE, JReversePro, Java Decompiler, Mocha, Jdec, just to name a few. --Spoon! (talk) 07:41, 20 September 2009 (UTC)

Thanks, I'm not trying to reverse engineer the program. I have all the source code or can download it. I'm just trying to run it under a debugger so I can step through it and understand better what it does so I can modify it. It's a fairly standard problem of getting a bunch of unfamiliar tools to work together causing a lot of farting around even though the high-level task is straightforward. 70.90.174.101 (talk) 07:53, 20 September 2009 (UTC)

Not sure what the problem is? If you can load the source code into the IDE you should be able to debug - step in/over etc.

Was there a particular bit that was a problem. Isn't the source provided as a single package, or in a single directory?83.100.251.196 (talk) 10:23, 20 September 2009 (UTC)

The source is a bunch of different packages including some downloaded libraries. There are maybe 1000 or so classes. I haven't been able so far to load the source into either Netbeans or Eclipse (requires adjusting the build scripts to compile with debugging info, figuring out how to tell the debugger where to find the dozens of directories of sources, getting versions of the debuggers that don't hang or crash with specific JVM's, etc.) It's one of those situations like when you want to click something to print a document, and you end up spending days screwing around with printer drivers, installing fonts, etc. There seems to just be a lot of java infrastructure that java developers have to get used to, in addition to learning the actual language. That's what I'm asking for advice about 70.90.174.101 (talk) 17:37, 20 September 2009 (UTC)

I assume you are new to both IDEs then? There are introductory tutorials for them eg http://java.sun.com/developer/onlineTraining/tools/netbeans_part1/ , and probably something similar for eclipse if you look. I'm not sure if there is an quick way to get started - I think you would at least need to read some of the tutorial first. As a first guess to get started quickly - have you tried creating a new project, downloading all the files, and dumping them into the project folder? (and finding the 'refresh project button')

Also, do you need previous build version info? or just the current build? If the second you just need the source code text files I think (might be missing something) - once inside a project you should be able to select the project, press build, and then be able to debug. Apologies if I'm oversimplifying the process - I don't know just how complex this project is.83.100.251.196 (talk) 18:26, 20 September 2009 (UTC)

(unindent) Thanks, yes, I'm pretty new to both IDE's, and also to the general culture of Java development. In C development I'd get debugging info from the compiler by putting "CFLAGS=-g" into the makefile, and I'd have a few directories where all the source code was and I'd point gdb at those directories. So I'm trying to figure out how to do the equivalent in Java, which uses build.xml (for Apache Ant) instead of a makefile. The source files are scattered across several dozen directories that are separated from the jar files where the class files are. It would be great if I could just tell Netbeans to recursively crawl a directory structure and find all the java files but that doesn't seem possible. There doesn't seem to be a way to build the whole program completely from source with one command, rather than building a bunch of jar's with separate scripts. I don't care about previous build version info, at least for now. I just want to run the program under debugging, so I can see how a few specific inputs get treated as they make their way through the program. I see the netbeans tutorial mentions a compilation classpath so I guess I should figure out how to set that up. Maybe I'm just being lazy and the classpath really does have to have dozens (maybe even 100's) of nested directories. Is that reasonably normal when using Netbeans? This program is nowhere near as big as, say, the Linux kernel, but its source tree seems almost as complicated. 70.90.174.101 (talk) 21:15, 20 September 2009 (UTC)

Add a new application

How can i add a new application in orkuts application dictionary?

The Bank of England has got MUMPS

What exactly does the BoE use Mumps for? And similarly, why do other financial organisations use MUMPS in preferance to more modern languages? 84.13.198.33 (talk) 10:47, 20 September 2009 (UTC)

I don't know the former, but as for the latter: here is an article about COBOL, and why aging infrastructures use it. (Looks to be similar as the MUMPS example.) The short answer is that to revise their systems at this point would be a massive investment—these systems are decades old and have millions of lines of code and if they seem to be working, nobody wants to dare touch them, for risk of screwing up massively important businesses, health facilities, governments, etc. Working on projects of that size and magnitude is difficult and expensive—it's easier and cheaper for them to just keep patching it up as time goes by than to risk screwing it up majorly in an overhaul. --98.217.14.211 (talk) 14:14, 20 September 2009 (UTC)

Very easy to learn english-like and other computer languages

I'm thinking of things like COBOL, MUMPS, SQL, and so on. I can program in BASIC, and years ago I used Logo as well. I'm interested in doing things like writing a simulation of a growing property (UK-eng) or real-estate (US-eng) rental portfolio, and downloading information from databases off the internet, and so on. What very easy to learn languages would people recommend learning? Because I do not do much programming, it is not worth spending the time learning a more difficult language. Thanks 84.13.198.33 (talk) 10:56, 20 September 2009 (UTC)

If you go to read COBOL or SQL you'll find they really aren't easier. So if english-likeness is not an requirement I would recommend python or perl. --194.197.235.240 (talk) 11:18, 20 September 2009 (UTC)

Yeah, COBOL and SQL are actually NOT easy. You'd be better off just taking the plunge and learning a more flexible language. 90% of a language is just understanding the syntax—the grammar, as it is. Once you do that, many are quite straightforward. A scripting language (like python, perl, PHP, etc.) is going to be probably what you want. --98.217.14.211 (talk) 13:59, 20 September 2009 (UTC)

With long function and variable names, an object-oriented language like Java or C++ can sound almost like a pidgin English. Most of the control-flow is direct use of the English equivalent, e.g. "if", "else", "try", "catch", "finally", "do", "while", ... etc. Nimur (talk) 15:36, 20 September 2009 (UTC)

Programming Lanuage Selection

I know php/html and do simple CLI programming with it, but lately need something that will allow me to do GUI exe's. I have considered php compilers (such as bamcompile) but they either don't do GUI (php-gtk) or support php5. I think C will be too low-level for me. Microsoft Visual Studio Express seems promising, but I'm not sure what to choose. Thank you for your suggestions. Waqqasd (talk) 14:39, 20 September 2009 (UTC)

Visual Studio Express is a great programming environment, IMHO. You will obviously need to learn C# or Visual Basic .Net, and the ins and outs of programming .Net, but there's a lot of books and material on the web that will help. --Phil Holmes (talk) 17:32, 20 September 2009 (UTC)

A friend of mine found Qt] a good way to jump from CLI to GUI programming as a Perl programmer; there are apparently PHP bindings for that as well. If it were me, I'd probably look into that first. VB.NET is a whole other kettle of fish, and not very fun or intuitive for the most part. (VB itself was more straightforward, for all of its problems.) --98.217.14.211 (talk) 19:06, 20 September 2009 (UTC)

Using the speed of USB 2.0 to record several audio tracks separately

I was inspired by the alesis multimix 16, as it can record 16 audio tracks separately. A few problems though - I already have a decent mixer, and the alesis one is super-expensive. I would like to build a device which takes 16 mono inputs and records them separately through a USB port. I have never used USB or computer interfaces in my electronics and need some help. Problems i foresee are:

figuring out how to make the computer know that the device has 16 audio ins

making a timing device to send samples from each of the 16 ins one at a time i.e. send the first sample of all 16 ins in order, then the seconds, then the thirds and so on... so that the computer can determine which of the 16 ins it is reading by what time it was sent at

Are there any other problems that I will encounter? Anything i've missed?

Any help is appreciated! 89.241.28.24 (talk) 18:23, 20 September 2009 (UTC)

Computers can have multiple sound adapters right now - be they soundcards inside the case (connected to the PCI bus) or outside (on USB cables). So what you'd typically do is just add a bunch of these to a given machine; if the driver software is half decent then all these will appear in the OS as audio input devices, and you need only configure your audio recording software to match track1 to adapterA, track2 to adapterB, etc. If you didn't need studio quality audio (just half decent) you could do that today with off the shelf soundcards/usb-boxes. Now I guess you do want studio quality. I don't know if genuine studio-quality soundcards/usb-boxes are available; if they aren't, or if you really want to build them yourself, you'd typically take the reference design supplied by the audio-chip manufacturer and use higher-quality analog-side components. Actually building high-quality USB audio components like this is a serious project (a business, really), as you'd need a good analog/signal electronics person, a half-decent digital-design person, and (if you can't rely on the audio drivers supplied by the chip company) a windows (mac, linux, whatever) device-driver software person. -- Finlay McWalter • Talk 18:54, 20 September 2009 (UTC)

If you're designing and building the hardware yourself - I would add in a "USB engineer" to the mix of required skills, which is an elite specialist who understands the USB protocol details very well. For stability and performance, you may need a full-time engineering or programming professional just for that aspect of the system. The Specification is hardly a user-friendly document. Nimur (talk) 20:36, 20 September 2009 (UTC)

Is my University using a NAT network

My reasons for believing that is IS are:

1. The University is a large organization.
2. I cannot access (or even ping) university machines from outside of the network (unless I'm using VPN).

and my reasons for believing that it ISN'T are:

1. Tools such as this give different IP addresses on different university computers - these addresses correspond to those registered by tools like ifconfig.
2. To my knowledge, local networks using NAT have certain conventions for IP addresses - the campus network, if it's functioning as a NAT, breaks these.

So, from this, is it possible to tell? Thanks.--Leon (talk) 20:16, 20 September 2009 (UTC)

It may be using a firewall without network address translation. In many home routers, the firewall and the NAT are provided by the same piece of hardware/software ("the router"); but in a large network, they are usually separate - both conceptually, in the service that they provide; and in implementation - in that they are managed by separate hardware. It is very common to block certain ports and firewall certain network traffic patterns, without performing NAT. Nimur (talk) 20:33, 20 September 2009 (UTC)

(edit conflict) Neither of your "for" reasons is really valid (the latter one just shows that a firewall is blocking ICMP, which is common). Both of your "against" reasons are valid; if public addresses==actual addresses, then (by definition) they're not being translated (which is the essence of what a NAT is). So they're not using NAT, they've just got a firewall (probably a pretty smart stateful firewall). -- Finlay McWalter • Talk 20:38, 20 September 2009 (UTC)