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July 11

How to delete floppy disk stuff from BIOS (http://www.gigabyte.com/products/product-page.aspx?pid=3610)

I have searched around inside the BIOS, I have flashed them to the newest version, but it seems I cannot find the command to disable floppy disk anywhere. I need to do this so I could use GParted to partition my drive so I could dual boot linux into that — Preceding unsigned comment added by 140.0.229.26 (talk) 00:01, 11 July 2013 (UTC)

You shouldn't need to disable the floppy disk in the BIOS. With GParted, you can select which device it is working on - the control for that is in the upper right of this image. If you really, really must disable the drive, why not open the case and try disconnecting the cable. Astronaut (talk) 16:15, 11 July 2013 (UTC)

I haven't make this clear but I don't have any floppy drive, who use that today? And if I didn't disable the floppy drive it stuck at scanning devices 140.0.229.26 (talk) 13:41, 12 July 2013 (UTC)

The reason why you can't disable the floppy disk in your BIOS is probaly because your mobo has no native support for a floppy disk. This is clearly visible in both the images and and the specs of the link you provided, as well as the manual [1]. I don't know what problem you are having but I don't see any reason to think it has anything to do with a floppy disk particularly if you haven't attached an addin card to that provides a FDD port, and you didn't explain why you believe it's the cause of your problem either. It would be helpful if you better explain where exactly you are having problems and what, if any, error messages you get after waiting a resonable length of time (say 15-20 minutes), what you've tried to do to resolve the problem (e.g. if you have multiple devices did you try disconnecting all but the one you want to work with) and more info on your set up etc etc. Your first post was entirely unclear, you second post only clarified very slightly. I presume GParted getting stuck somewhere, probably at startup, but other then that I don't know much else and as I said it's entirely unclear why you think the problem related to a floppy drive. Nil Einne (talk) 16:25, 13 July 2013 (UTC)

Mouse scrolling making BROWSER problems...

I have this EXTREMELY annoying bug... I CAN'T get rid of.

It started a while ago, I don't even know how, just started, one day.

when I scroll on pages, mostly UP, it turns into the normal scroll-up icon and when I press other tabs in google chrome it CLOSES them... and the START BAR won't work either... it's like frosen and when I press back on pages after having SCROLLED, it creates a new with the same page... WTF is going on.. why is MOUSE SCROLLING causing computer problems AND browser problems? This comp is 3 months old............. — Preceding unsigned comment added by 212.30.207.211 (talk) 02:50, 11 July 2013 (UTC)

I doubt it's your computer - it's probably Chrome's doing. Have you installed any new addons recently? Disable those one by one and see if the problem stops. If that doesn't work you could try reinstalling Chrome. --Yellow1996 (talk) 16:18, 11 July 2013 (UTC)

For the record, pressing the scroll wheel down (this is referred to as clicking the middle mouse button) while pointing at a tab will close the tab. It's meant to do that. That's how browsers are programmed, it's just a short cut. I'm not sure about the rest. Falastur2 ^Talk 21:24, 11 July 2013 (UTC)

Point and shoot cameras

Does the amount of megapixels significantly affect image quality in a point and shoot camera? I ask as I find that a 4 megapixel point and shoot camera can take photos with better image quality than an 8 megapixel smartphone camera. — Preceding unsigned comment added by Clover345 (talk • contribs) 12:01, 11 July 2013 (UTC)

That's the usual situation. Megapixel is often mistakenly used as a figure of merit. See Digital_camera#Image_sensors. Pixel count can make a difference, but I often get better results from an old 2 Megapixel camera than a new 14 Mpx one. Jim.henderson (talk) 12:22, 11 July 2013 (UTC)

Megapixels will make a difference on print quality, and more megapixels lets you print on larger surfaces. About 8 megapixels allows you to print at a good quality level on a 8.5" per 11" sheet of paper (~300 Dots per inch), so more megapixels than that will generally not be very useful. Digital displays need even fewer megapixels - 1080 HD is only about 2.1 megapixels. More megapixels reputedly allow for more flexibility in post-processing. 64.201.173.145 (talk) 14:24, 11 July 2013 (UTC)

It depends. All other things being equal, a higher number of pixels allows a better depiction of fine details. On the other hand, for any given camera design, a higher resolution on a sensor of the same size means that the ccd elements are smaller, and thus more susceptible to (thermal) noise, so that the image often looks more washed out. Also, for most applications there is a useful limit to the number of pixels - your pixel resolution does not need to be better than your optical resolution, or your print/display resolution. Finally, all other things usually aren't equal. Better optics, image stabilization, and even such a trivial thing as ergonomic shape of the camera body will have an influence on the quality of the image. Not to mention the skill of the photographer in picking and arranging motives and knowing about good and bad lighting conditions. I've seen Japanese tourists trying to light up St. Peter's Basilica with the Flashcubes of their Instamatics. Small negative size was not the major problem with those photos ;-).--Stephan Schulz (talk) 14:43, 11 July 2013 (UTC)

Yeah. For smart photographers with high end hardware, Megapixels can make a difference. When the rest of us point our little P&S, the part that spoils the picture we put in Wikipedia is under our hat. Jim.henderson (talk) 15:05, 11 July 2013 (UTC)

Sometimes turning down the resolution on a camera can help get better shots. The camera will still capture at the full resolution, but combine adjacent pixels. This can help smooth out noise or let you get away with a shorter shutter time in low light situations. Your point-and-shoot also probably has a much better lens than your phone. 209.131.76.183 (talk) 15:29, 11 July 2013 (UTC)

Probably 8 magapixels is no better than 4 megapixels on a camera like that. Those cameras have really low-quality lenses and everything else. Bubba73 ^{You talkin' to me?} 01:06, 12 July 2013 (UTC)

computer infected by virus

My net book is badly infected by a virus."registry editor is disabled by administrator" message appear when ever try to edit reg ,I can not open taskManager ,it is also disabled by admin appears.every computer folder has a subfolder with same name ,I am not able to delete them manually.Run command is missing from start menu,It does not allow me to download antiviruses on line .It does not allow me to download acrobat reader from internet. Is their any online solution or other ,otherwise I have to re install windows xp again, — Preceding unsigned comment added by 182.187.77.255 (talk) 23:18, 11 July 2013 (UTC)

Go to C:\WINDOWS\system32\drivers\etc and you should see a file called "hosts". Open it in Notepad, blank it completely and set it to read-only, then reboot your computer. Can you access antivirus websites after that, or does the virus recreate the file? Post back here, thanks. Ginsuloft (talk) 23:22, 11 July 2013 (UTC)

And if it does recreate the hosts file then you can transfer an AV software via USB stick since it won't let you download one directly on the computer. --Yellow1996 (talk) 01:18, 12 July 2013 (UTC)

Just my two bits, but I'd go with the wipe and reload. You can fight with the virus if you so choose, but you have no idea how long you will be battling it or how extensive the infection is or if it will still be lurking on your system after you think you've gotten rid of it, only to manifest itself again at a later time. When you wipe and reload, only then can you be certain it's gone.

When you reinstall Windows, get ALL of the security updates before you surf the web on that computer again. Also use a different browser than Internet Explorer. And consider switching to a new operating system soon; support for Windows XP ends on April 8, 2014, which means no more security updates.

If you need to transfer data from the old install to the new, ensure that AutoRun is turned off before inserting potentially virus-tainted media on your fresh install. Transfer no executable files if you can avoid doing so. Images and documents are fine.

Good luck! -Amordea (talk) 03:35, 12 July 2013 (UTC)

For the taskmanager, try going to C:\Windows\System32\, copy the taskmgr.exe file to somewhere else, rename it winlogon, then try to open it. A lot of malware will let programs named winlogon run since it's required to get windows going. You might also try the same thing with the registry editor (if you're brave). If you can, via this or other, get a copy of hijack this running, if you want to post the logfile on my talk page, I'd be willing to take a look and help you figure out what's gong on.Phoenixia1177 (talk) 03:53, 12 July 2013 (UTC)

You can also try the following: get a version of linux you can boot from usb, like [2]; boot from it; clean up any obvious garbage; try booting from windows. If you still can't get windows to work: there is a folder on XP, somewhere in the Windows directory, that contains clean versions of your registry files (it's called repair, or recovery, or some such); swap those out with your actual registry; boot in windows; open regedit; load your actual hives; clean them up (I'm guessing you know how from referencing regedit); reboot from linux; swap them again; try windows.Phoenixia1177 (talk) 12:39, 12 July 2013 (UTC)

July 12

Bugged by design Microsoft vs HIPAA

Now that M$ baked in insecurity has been leaked...

http://www.guardian.co.uk/world/2013/jul/11/microsoft-nsa-collaboration-user-data

Isn't it a violation of the Health Insurance Portability and Accountability Act to use any M$ spyware in any doctor's office, hospital or insurance company? Hcobb (talk) 00:49, 12 July 2013 (UTC)

The reference desk isn't able to decide what is legal and what is illegal - that would be providing legal advice.

My position is twofold: first, the media is sensationalizing a "breaking story" about something that is actually very commonplace, and has been commonplace for decades, in many forms, technological and otherwise. Various media providers may have a vested interest in all this mudslinging; newspaper articles like the Guardian article you linked are not doing a great job of providing a neutral point of view.

Secondly, just because something is morally objectionable (to some people) - like massive government surveillance and corporate collusion - it is not necessarily illegal. Law is so complicated that attorneys spend years studying it. Even then, lawyers rarely agree with each others' interpretations. It is very probable that the various parties involved took great care to ensure that they were totally complying with relevant laws. For example, this press release Statement to the NSA/CSS workforce, states clearly: "Through four years of oversight, the committee has not identified a single case in which a government official engaged in willful effort to circumvent or violate the law." Nimur (talk) 01:32, 12 July 2013 (UTC)

The article doesn't seem to be describing MS illegally forcing records on the NSA, it sounds like the NSA legally obtaining records from MS with their cooperation (Apple, Google, etc. were mentioned too). I'm pretty positive if everybody suddenly quit using Google, MS, etc. because of NSA and CIA surveillance, that they would use their authority to monitor whatever service everyone switched to. The issue isn't MS, the issue is the NSA, CIA, and FBI (if you have an issue), you can always consult a lawyer and see about challenging them...but I doubt that would go anywhere.Phoenixia1177 (talk) 04:08, 12 July 2013 (UTC)

HIPPA has all sorts of carve outs for legally authorized disclosures, and even if it didn't, it'd be hard to argue that you couldn't, for instance, obtain certain information in a criminal defense. Armchair lawyering like this tends to go from conclusion to reason, and rarely holds up to an even cursory reading of the law. On that point, I've got zero inclination to do the latter. Shadowjams (talk) 06:36, 13 July 2013 (UTC)

Were you responding to me or the op?Phoenixia1177 (talk) 07:27, 13 July 2013 (UTC)

CPU clock discrepancy

When I ran CPU-Z with my Core i7 2600K at factory settings, which include FSB at 100.0 MHz, CPU-Z reported the front-bus speed as actually 99.77 MHz, and a CPU clock speed consistent with that slightly slower FSB. I've since changed my FSB setting in BIOS to 100.3 MHz, and CPU-Z reports 100.10 MHz. Does this mean the CPU clock is running slower than the real-time clock? If so, which one is likely to measure a second more accurately? (I bought the CPU and motherboard at the same time.) NeonMerlin 13:10, 12 July 2013 (UTC)

Late reply but...

Because an early (as in "running too fast") real-time clock would be wrong by 8.64 seconds per day if it were only 0.01% faster than a perfect cock, it is safe to assume that your bus is actually a bit on the slow side.

However, I'd ask you if your PC is actually doing a solid hour of I/O per day? If it is, the slow bus would result in a 7.9 second penalty compared to the "perfect motherboard" - not really worth correcting for speed reasons.

IIRC, the bus tolerances are 1.5% - i.e. there could be seven times the deviation your bus clock exhibits before you'd run a risk of into any signal corruption.

But if you want to get it right for rightness's sake, "100.3" (that is, 100.07 MHz) is certainly a closer fit than 99.77 MHz. Just don't expect any significant speed or reliability increase from it. - ¡Ouch! (^{hurt me} / _{more pain}) 07:14, 16 July 2013 (UTC)

*clock. Damn, Google's gonna give us a lot of traffic for this one...- ¡Ouch! (^{hurt me} / _{more pain}) 07:25, 16 July 2013 (UTC)

Error debug

Hey there! I was working with nested switch case in C++ language. The code i developed gives 0 error and 0 warning. But it does not execute any of the switch. It just exit. Can any one please tell me where the mistake is . I have got stuck. Any help will be highly appreciated. Thanks

C++ code

# include <iostream> # include <math.h> # include <conio.h> using namespace std; int main() { int option; // variable for option for the type of photo int op; // option for size of photo int np; // option for number of photos int cop; // cost of photo cop= 10; // price of one photo int cost_photo; cout<<"\nEnter the option number from following for the type of photo you need"; cout<< "\n1. coloured photograph" ; cout<<" \n2. Black & White photograph"; cout<< "\n3. sketch " <<endl ; cin>> option ; switch (option) { case '1': cout<< " \n1.Passport size photograph"<<endl; cout<<"\n 2.9 x 4 photograph"; cout<<"\n 3.5 x 11 photograph"; cout<< "\nplease enter the photo size option fron above options\n"; cin>> op; // takes the option as input for size of photo switch (op) { case '1': cout<< "\nHow many photgraphs are required\n"; cin>>np; cost_photo= (cop*np)+5; cout<< " Your total bill is "<<cost_photo<<endl ; break; case '2': cout<< "\nHow many photgraphs are required\n"; cin>>np; cost_photo= (cop*np)+10; cout<< " Your total bill is "<<cost_photo<<endl ; break; case '3' : cout<< "\nHow many photgraphs are required\n"; cin>>np; cost_photo= (cop*np)+15; cout<< " Your total bill is "<<cost_photo<<endl ; break; default: cout<<"Please enter the correct option"; } break; case '2': cout<< " \n1.Passport size photograph"; cout<<"\n2.'9 x 4' photograph"; cout<<"\n3.'5x11' photograph"; cout<< "\nplease enter the size option\n"; cin>>op; // takes the option as input for size of photo switch (op) { case '1': cout<< "\nHow many photgraphs are required\n"; cin>>np; cost_photo= (cop*np)+20; cout<< " \nyour total bill is "<<cost_photo ; break; case '2': cout<< "\nHow many photgraphs are required\n"; cin>>np; cost_photo= (cop*np)+30; cout<< "\n your total bill is "<<cost_photo ; break; case '3': cout<< "\nHow many photgraphs are required"; cin>>np; cost_photo= (cop*np)+45; cout<< " Your total bill is "<<cost_photo<<endl ; break; default: cout<<"Please enter the correct option"; } break; case '3': cout<< " \n1.Pencil sketch"; cout<<"\n2.'charcoal sketch"; cout<< "\nplease enter the sketch type option\n"; cin>>op; // takes the option as input for size of photo switch (op) { case '1': cout<< "\nHow many photgraphs are required"; cin>>np; cost_photo= (cop*np)+20; cout<< " Your total bill is "<<cost_photo<<endl ; break; case '2': cout<< "\nHow many photgraphs are required"; cin>> np; cost_photo= (cop*np)+30; cout<< " Your total bill is "<<cost_photo<<endl ; break; default: cout<<"Please enter the correct option"; } break; } getch(); return 0; }

Mike robert (talk) 15:29, 12 July 2013 (UTC)

You're doing what amounts to:

  int option;
  cin >> option;
  if (option == '1') ...

so in that last line you're comparing the int option with the char '1' (which, because it's ascii, is 49, not 1). You probably just want case 1: not case '1'

-- Finlay McWalterჷTalk 16:58, 12 July 2013 (UTC)

Thankyou so much. I didnt notice that. Now it's working. :)Mike robert (talk) 17:08, 12 July 2013 (UTC)

Is there a frexp function for JavaScript

The frexp function found in the standard c library exists as a function in JavaScript? I've looked everywhere but I've found nothing. Where can I find it? 181.50.178.92 (talk) 23:42, 12 July 2013 (UTC)

Unless you are using an exotic JavaScript interpreter, there is no frexp function built in. You can compose the same mathematical functionality using Math.log (and related functions), part of the standard Math object; or by writing your own function - it might be a good exercise in practical applications of recursion!

If you want to live dangerously, you can attempt to implement a constant-time algorithm (instead of an O(log(n)) time algorithm by directly inspecting the binary representation of the floating point numeral - chances are very good that it's stored as a IEEE 754 numeral (on any sane JavaScript implementation). But if you walk down this dangerous road, you will soon realize that JavaScript doesn't make this style of programming very easy - for one thing, type punning is not defined, because JavaScript is type safe and dynamically typed. Nimur (talk) 01:25, 13 July 2013 (UTC)

This should get the internal representation of a float (which on my nodejs build is a single precision IEEE 754 float) as an int:

function float_as_int(fl){
    var ab = new ArrayBuffer(4);
    var fa = new Float32Array(ab);
    fa[0] = fl;
    return new Uint32Array(ab)[0];
}
console.log(float_as_int(3.1415));

That's essentially what in C would be:

  float pi = 3.1415;
  printf ("pi as an integer:%d\n",  *(uint32_t*)&pi);

-- Finlay McWalterჷTalk 02:29, 13 July 2013 (UTC)

A C implementation of frexp which uses the internal representation (it uses doubles) is here. That entails extracting the exp and fraction part of the IEEE number (the C code does it in macros), which (I haven't tested it) should be:

var num = float_as_int(3.1415);
var exponent = (num & 0x7f800000) >> 23;
var fraction = num & 0x7fffff;

then I guess you normalise per that code.

-- Finlay McWalterჷTalk 02:35, 13 July 2013 (UTC)

Since we're doing things the hard way, and I've already implemented this code, I may as well share it... in Python, the math object in the standard library implements frexp, but I wrote a function myself just to be sure I could.

A Python (re)implementation of frexp

#!/usr/bin/python
import math

x = -4271.437    # example input

exp=0;
while (2**exp < abs(x)):
        exp += 1
fr = x / 2**exp
result = (fr, exp)

print (result)
print (math.frexp(x))   # sanity check against the math.frexp version

The same, frexp, in HTML4 and JavaScript

<HTML>
<BODY>
<!--
<SCRIPT language="javascript">
var x = 4271.437;

var exp = 0;
while(Math.pow(2,exp) < Math.abs(x))
{
   exp += 1;
}
var fr = x / Math.pow(2,exp);

document.write("<br/>FR=");
document.write(fr);
document.write("<br/>EXP=");
document.write(exp);
</SCRIPT>
//-->
</BODY>
</HTML>

The real meat of this algorithm is only a few lines of code, and did not require recursion. You could trivially convert this to JavaScript. In principle, it should be safer - and slower - than Finlay's version; but that depends on your exact needs and use-case. You might also want to check the behavior on weird floating-point inputs like NaN and negative zero.

Also, I'm impressed that Finlay found a way to type-pun in JavaScript. His code works! But that sort of hackery should probably be avoided if you're deploying your script via the web - you never know how it might break on weird clients! Supposing somebody's running your JavaScript in Netscape on a really old SPARC or an IBM 390, or a VAX? In all seriousness, it's really unlikely JavaScript will ever run on a machine whose floating-point format is not IEEE 754, but it's still not a good idea to make assumptions about endianness or binary formats. Nimur (talk) 06:03, 13 July 2013 (UTC)

July 13

Windows 7 Administrator

I am running windows 7 on my PC. When I try to do a scan with my anti-virus software, it says I am not an Administrator. I am the only one who uses this computer and have no idea how to elevate myself to becoming an Administrator. Any help would be appreciated. 99.250.103.117 (talk) 00:42, 13 July 2013 (UTC)

If you have the only account on your computer, then you should be an admin already. You can read more about admin rights in Windows 7 here (how to change an account's status, etc.) Hope this helps! --Yellow1996 (talk) 01:21, 13 July 2013 (UTC)

When you open it, instead of double clicking: right click, select run as administrator, it will ask if you are sure, say yes. If this doesn't resolve it, you may have malware (or some other unwanted situation); if you do, I'd be willing to work with you to see about fixing things up.Phoenixia1177 (talk) 05:15, 13 July 2013 (UTC)

VisualSubSync Help

I am doing a subtitling job at the moment, and I am not entirely familiar with the software I have been requested to use. I have done a minute or so of this (short) video, but I would like to test it, to see if the subtitles are in the right place. Can anyone tell me how? KägeTorä - (影虎) (TALK) 09:38, 13 July 2013 (UTC)

It looks like VisualSubSync will let you display the video in the editor (in the View menu, select Show/Hide Video), but I think it might only work if Windows can understand the video codec. Try it and see if the video shows up. If not, here are some ideas that might get it to work:

• Re-encode your video. When I tested an example video in VisualSubSync, the Show/Hide Video command didn't do anything. I used ffmpeg to re-encode the video to mpeg1, then VisualSubSync could display it. If your video is short (a few minutes), re-encoding might be reasonable. If your video is long, then re-encoding might take a long time.

• Install a codec? If your video doesn't show up in VisualSubSync, maybe installing a codec would help it display the video? In VLC Media Player, you can go to Tools, Codec Information to get information about the codec it's using, then perhaps you could search online for a matching Windows codec. Be aware, my understanding is that malicious codecs can contain malware, so carefully evaluate if you trust a codec source before installing it.

--Bavi H (talk) 17:53, 13 July 2013 (UTC)

Additional: In the VisualSubSync menu bar, I went to ?, Help, Codecs installation, and it went to Installing codecs, which appears to have similar advice. --Bavi H (talk) 18:03, 13 July 2013 (UTC)

July 14

wikipedia from 50 years ago

I am trying to link to wikipedia from 50 years ago. However I want to do this dynamically, so that on july 12 2013 I want to provide a link to July 12 1963 on August 1 2013 I want to link to August 1 1963. I have a reunion website that I'm trying to show this info - we have a count down till the reunion and a formula that shows each day how many days left. I can change that link to any date I want...so I can use the counter to link to wikipedia; just don't know how to reflect the correct wikipedia link So July 12th is http://en.wikipedia.org/wiki/July_1963#July_12.2C_1963_.28Friday.29 and I want to figure out how to grab that page dynaamically and have it change each day. Thanks Dick — Preceding unsigned comment added by RLR170 (talk • contribs) 04:27, 14 July 2013 (UTC)

Depending on how your site is written, it's possible. You could prepare the link in a language such as PHP, and that would allow you to alter its contents to suit the day. As far as the actual code for that goes, it'd look something like this:

$year = date('Y')-50;
$month = date('F');
$day = date('j');
$weekday = date("l", mktime(0, 0, 0, date('n'), $day, $year));
echo "<a href='http://en.wikipedia.org/wiki/" . $month . "_" . $year . "#" . $month . "_" . $day . ".2C_" . $year . "_.28" . $weekday . ".29'>LINK TEXT HERE</a>";

That should result in the correct date being provided in link form. I hope this helps!  drewmunn  talk  07:39, 15 July 2013 (UTC)

(Second thoughts: this may not work as expected, as it is before the UTC creation threshold. If there is a way to link directly to a date without needing the day of the week, then that would be ideal)  drewmunn  talk  07:45, 15 July 2013 (UTC)

And it will act funny on Feb 29, 2012 if you make it 1962. Not sure if it's gonna be undefined, but I'd convert the date to Julian date, then subtract 50*365+13 (or 12, depends on which date you want to match exactly) days, then convert back into normal "YYYY-MM-DD" date.

I hope that's the way you want it to work. - ¡Ouch! (^{hurt me} / _{more pain}) 12:49, 16 July 2013 (UTC)

what sthe point of classes

How are you supposed to use classes?

When developing your own applciation, what's the point of a class hierarchy, I don't really get it. For example if I have an app that reads from the keyboard and the web cam as well, are these supposed to be different classes? Why?

The way I program now is I just put it all into one file with just Main() and some functions, some global variables. I don't really see a problem with the way Im doing it now --89.132.116.35 (talk) 12:53, 14 July 2013 (UTC)

Have you read Class or object oriented programming? Dismas|^(talk) 12:58, 14 July 2013 (UTC)

The first one has a very short Benefits section that I can't apply to the example above. It says "Computer programs usually model aspects of some real or abstract world (the Domain). Because each class models a concept, classes provide a more natural way to create such models." I don't see why it's any more natural than simply including 5 global variables in the file for each aspect of the system. There's nothing 'naturally' divided into classes in the whole system, I would have to add on this abstraction after the fact. I'm open to how this helps. But to be clear, without the class, I can do everything. What do I get out of applying a class structure to it? The second article you link has no Benefits section but does have a section Criticisms, which is far longer than the benefits section of the first article. I'm not trying to argue - I'd like to see how for me and my example, why I should try to do make classes out of this system, and how I would do so. --89.132.116.35 (talk) 13:23, 14 July 2013 (UTC)

Why should anyone attempt to demonstrate why it is better for "you" or "your example"? And why should it be? Generally it's much better to keep an organized file cabinet inside of an organized office, and if you're running a business, you're almost doomed to fail not doing this; on the other hand, if someone can get by tossing all their paperwork in a drawer, does this somehow make arbitrary the filing system used at giant corporations? Personally, I find it easier to think in terms of classes; I think it makes code more readable since it gives a general framework so you know what to expect; most things do break down into classes; and class structuring does scale well, while it's very hard to be certain random programmer Joe's structure will. Not to mention, going back to the general framework, it does make it easier to collaborate since it provides natural ways to divide up projects and layers of abstraction. However, all of that aside, if you can get by with your own personal system, no one's going to stop you. Finally, is their something specific that you would lose by using classes, do you see some large cost it imposes on what you're doing?Phoenixia1177 (talk) 14:03, 14 July 2013 (UTC)

Three examples from my own life. Last year I made a really laughable ray tracer, inheritance was really useful when it came dealing with various shapes; I think it would've been a nightmare to deal with it differently. I wrote a piece of image processing software that analyzed batches of input images and applied filters according to its logic; the end result was about 45,000 lines of code, being able to hide away chunks of code dedicated to reading files and sorting batches made everything a lot more manageable (since those things aren't really related to images). Finally, a few years back, my friend made some graphics and we ripped off Final Fantasy Tactics and remade the battle engine ourselves (it was more fun than chess); being able to logically organize things on the basis of if they were game data, or graphics data, or etc. and how they all fit together made natural sense when viewed as objects; I don't think that project would have ever gotten off the ground if we didn't have a simple, and clear, way to translate the abstract components into code components. You may disagree and not see the merit in any of this, and that's fine, but it is a useful system for many.Phoenixia1177 (talk) 14:25, 14 July 2013 (UTC)

You never need classes, just as you never need functions, or useful variable names, or types - these are all conveniences that allow you to fit a complicated program into your head, and to communicate it with other programmers. Simple examples of why classes are useful can be hard to come by, as simple programs are easy enough to fit into your head without breaking stuff up into classes. Instead of your keyboard+webcam app, let's say you were writing Robot Attack, a game where lots of robots live in a spaceship and kill foolish human interlopers. You'd probably have a big list of robots, and each tick of the game you check what each robot should do, and perform that action. Call each individual robot an instance. In a full featured game, there's a kinds of different robots: maintenance robots, patrol, security, battle, cargo transport, etc. Each kind (a class) has special behaviours (only patrol, battle, and security can fight, only cargo can move boxes, only maintenance can fix other robots that are damaged). But you notice that they all have some things in common - they can all pathfind around the spaceship, they can all open doors. So rather than replicating the movement and door code for each, you factor out that into a base class "robot". Now all the individual classes of robot are subclasses of that base class; and the code for the maintenance robot class only has the specialisation to do with specifically doing maintenance things (finding broken robots, fixing them, fleeing if it's attacked). We might look again at our simple class heirarchy of robots and decide that the fighting robots have common behaviour (they look for enemies and move to a firing position), so rather than repeating that code in the patrol, security, and battle robots we factor that out into an intermediate class. Now our class heirarchy looks like this:

  class Robot :: class FightingRobot :: class PatrolRobot
                                     :: class SecurityRobot
                                     :: class BattleRobot
              :: class MaintenanceRobot
              :: class CargoRobot

Now we can construct instances (specific robots) of a given class, and we need only specify the class to get all the behaviour associated with that class, e.g.:

  Robot nigel = new PatrolRobot(name="Nigel", health="low", patrolRoute="room1;room3;room5;room1")

...and the "nigel" bot will have all the characteristics of a PatrolRobot, and because all PatrolRobots are FightingRobots, he gets those characteristics and behaviours too, and because that class is in turn a subclass of Robot, he gets the basic movement stuff that's implemented there too. In addition to behaviour, each class can have attributes (data). So say all robot instances have a "model" attribute, which is the little 3d model to use when drawing that robot. Subclasses can override these attributes (so PatrolRobots get a different model than a generic FightingRobot). And individual instances (specific named robots) can override these too. So you might create the spaceship's guardroom like this:

 // create a couple of generic battle robots with the default settings
 Robot battle1 = new BattleRobot()
 Robot battle2 = new BattleRobot()
 // and the boss
 Robot boss = new BattleRobot(name="Evil Boss", model="evil_boss.model", health="hellatoomuch")

What we've done in deciding this class heirarchy is the crux of your question. We've a) analysed all the things in the program, b) identified common behavior and attributes between classes of things, and c) structured our code to abstract commonality to baser classes and special characteristics to "leaf" classes or to instances. For real programs that's often a complex task, as it involves understanding all of what's going on. And there's usually multiple ways to do it. Looking for a "benefits" and "criticisms" section in some text is beside the point; classes are like the bolts and girders an engineer uses to build a bridge - the engineer has to understand the problem he's solving and understand the characteristics of the components he has available to build it. -- Finlay McWalterჷTalk 14:38, 14 July 2013 (UTC)

Fast direct access and SSDs

This is a three-part question.

The problem: I have several large files that I need to access directly to get a small amount of data each time. This will be done many times, so access time is very important. The files are too big to hold in the computer's RAM and a hard drive is too slow.

1. Because access time is very important, I think the way to go is with a SSD. Is this the best way to go?

2. Reading about SSDs, the ones using RAM have much better access times than ones using flash memory, right? (It is OK if it is volatile memory because I can reload the files from HD if needed.)

3. Hardware issues. The target computer is a Windows desktop with USB3, eSATA, an extra 5.25" SATA-2, and extra PCI slots. The RAM SSDs I've seen are 2.5" form factor instead of USB3. Are there any USB3 RAM SSD? Is there an adapter to put them in a 5.25" place? Are there any for eSATA? There also seem to be mSATA which look like they plug into PCI, but they say that they need to connect to the SATA data, and they look like they are for laptops - will that work?

TIA. Bubba73 ^{You talkin' to me?} 17:17, 14 July 2013 (UTC)

1. If you only care about read times, probably yes.

2. If a drive contains RAM and a non-volatile store, the RAM is a cache. RAM doesn't get cheaper because it's in a hard disk - if you can't afford to buy system RAM big enough to hold these files, you can't afford to buy a drive with that same RAM in it either.

3. If you really care about performance, a PCI-express SSD, which cuts out the translation to a bus like USB or SATA, is what you want. But those are darn expensive. Regarding 2.5" SSDs: most consumer SSDs are this size, even those that go into desktops (because flash is so dense, and there's no need for motors and arms and stuff, that form factor is plenty big enough). -- Finlay McWalterჷTalk 17:35, 14 July 2013 (UTC)

Thank you, #1 - yes, direct access read time is the crucial factor. #2 - the computer is already maxed out at 16GB, which isn't enough for the files. #3 - I'll look for PCI ones. Bubba73 ^{You talkin' to me?} 17:54, 14 July 2013 (UTC)

I've been looking at the PCIe SSDs - I didn't know about those until you told me. It looks like a 120GB one of those is the way to go for my needs. Thank you! Bubba73 ^{You talkin' to me?} 20:05, 14 July 2013 (UTC)

Make sure the one you choose has a driver for your version of Windows; some only have drivers for Windows Server. -- Finlay McWalterჷTalk 21:19, 14 July 2013 (UTC)

I'm looking at some by OCZ, and someone said that it didn't work with their Linux system but it did with W8, which is what I have.

There are some very fast ones out there, but they are very expensive. Bubba73 ^{You talkin' to me?} 01:48, 15 July 2013 (UTC)

IOPS and RAM

IOPS has some good example data for hard drives and SSDs. Roughly what is a comparible number for RAM? Bubba73 ^{You talkin' to me?} 23:56, 14 July 2013 (UTC)

Memory speeds depend on more factors than most people want to be bothered with; modern DRAM is really really complicated. In the aggregate, you can average the data transfer speed; a table is included as part of our article on CAS latency, section Memory Timing. Surprisingly, the performance of modern RAM technology actually depends on the cadence and timing of data access; and it also depends on what data addresses are accessed; in other words, the "random access" in RAM is not a very apt descriptive term. Just like hard disk drives, RAM data access is faster if you make use of spatial locality. Nimur (talk) 01:11, 15 July 2013 (UTC)

Spatial locality is a factor because it increases the cache hit rate, not because of any "seek time" inherent in the RAM. Pentium-class machines cache 16 bytes at a time, even if you only read one. Bobmath (talk) 16:05, 15 July 2013 (UTC)

Of course caches external to the RAM are also improved by spatial locality. But, because of the way that RAM works, spatial locality is a factor in the RAM itself: because column-addressed DRAM returns (e.g.) 8 words nearly as fast as it returns one word. If you don't need the latter seven words, you wasted a column select control signal; you've already spent that time to query those data, and they're available on the data out port. Have a read at control signals for SDRAM. Few people use the term "seek time" to describe RAM, but it is actually a very apt description. Nimur (talk) 18:34, 15 July 2013 (UTC)

I'm wondering about the time to get 50-100 continuous bytes from memory on a modern Windows desktop, using DDR2 or DDR3, when the information is almost certainly not in the cache. Bubba73 ^{You talkin' to me?} 01:41, 16 July 2013 (UTC)

The answer to that question - in isolation from all other details - is "less than a microsecond" - counting round-trip time to the RAM, plus all the control signal "details." Accessing data in main memory - with something modern like DDR3 SDRAM - requires on the order of tens of nanoseconds per transaction - as fast as cache memory was, just a few years ago! This is why all the ugly details matter: when you are reading only 50 or 100 bytes from memory, your total time is not dominated by the average performance of the RAM, because your statistical sample is so small. If you are only reading 100 bytes, your total execution time is probably dominated by when the operating system chooses to schedule your program. Nimur (talk) 13:42, 16 July 2013 (UTC)

July 15

facebook names

I recently created one of these 'facebook accounts' but being silly, thought it'd be fun to make up an amusing nickname rather than using my real name. a couple of days later, I regret that, and have avoided using the site since, so I'm wondering, is it possible to change from that to my real name instead, or would I have to close that account and create a new one?

213.104.128.16 (talk) 16:51, 15 July 2013 (UTC)

Check out this page. Hope this helps! --Yellow1996 (talk) 17:24, 15 July 2013 (UTC)

What's the Apple equivalent to MS Paint ?

StuRat (talk) 20:08, 15 July 2013 (UTC)

There hasn't been a direct equivalent since MacPaint was discontinued in 1989. WikiPuppies _bark ^dig 20:54, 15 July 2013 (UTC)

Anything close then ? StuRat (talk) 21:06, 15 July 2013 (UTC)

Try Paintbrush. WikiPuppies _bark ^dig 21:09, 15 July 2013 (UTC)

Thanks. Is that free ? Does it need to be downloaded ? StuRat (talk) 18:37, 16 July 2013 (UTC)

It is open source. It is free. Download it here. Richard-of-Earth (talk) 19:28, 16 July 2013 (UTC)

WinRAR safe from PRISM?

Dear Wikipedians:

Are WinRAR encrypted archives safe from PRISM?

Thanks,

76.75.148.30 (talk) 20:59, 15 July 2013 (UTC)

And also TrueCrypt?--128.237.207.243 (talk) 21:29, 15 July 2013 (UTC)

Maybe. Firstly the ciphers they use, such as AES are strong; used properly, it's impractical for anyone in the public cryptography community to break them. But NSA/GCHQ have an impressive number of mathematicians working on this kind of thing, and vast compute infrastructure - in the past they've been years ahead of public (that is, academic and commercial) cryptographic researchers. We don't know whether they've got a tractable means of breaking ciphers like AES; you can bet your life they're trying hard to acquire one. Secondly is the whole cryptosystem - how the ciphers are used, the keys managed, entropy generated, and so on. That's often more involved, less standard, and with a bigger attack surface; add the fact that these systems then need to be reduced to practice (actually written as software code running on a real system) means there's lots more opportunities for things to be invisibly defective. As Stuxnet shows us, governments actively research security vulnerabilities which aren't public knowledge (and keep them secret until they have need of them); it's optimistic to imagine that WinRAR and TrueCrypt don't have such vulnerabilities. Whether they're enough for a breach, again who knows. Surely any kind of encryption will go some way to frustrate the mass trawl for data that PRISM is claimed to do; but detecting encrypted data is easy, so it's not unreasonable to imagine using cryptography might lead PRISM to pay special attention. Lastly, particularly for anyone being specifically targeted, breaking the cryptography is far from the most obvious thing a security service would do - there's any number of ways to avoid needing to (virus on your machine, tap your keyboard, revolver-to-the-forehead). -- Finlay McWalterჷTalk 22:11, 15 July 2013 (UTC)

PRISM only captures data sent over the Internet, so a RAR archive or TrueCrypt volume would only be visible if you sent it as an email attachment, for example.

The current versions of RAR encryption and the TrueCrypt format have no known cryptographic weaknesses. It's impossible to prove that the NSA doesn't have a secret attack, but most academic cryptographers think it's unlikely, and if they do have one it would be an extremely valuable and closely guarded secret and they wouldn't risk exposure by using it against people like you. All major governments are certainly sitting on large collections of publicly unknown software vulnerabilities, perhaps even including vulnerabilities in the WinRAR or TrueCrypt software, but a practical attack on the file formats is another matter—that would very likely extend to other similar cryptosystems, including those used by banks and such to protect information that really needs protection. -- BenRG (talk) 00:29, 16 July 2013 (UTC)

Attacks on RNG systems are apparently the most fun, and as the debian openssl fiasco proved, these vulnerabilities can go on unnoticed for quite a while. Who knows if the NSA has some hack for AES; it seems almost unnecessary. Shadowjams (talk) 06:26, 16 July 2013 (UTC)

You're right, an RNG-related attack is plausible. I actually looked at TrueCrypt's entropy generation and it seemed okay, but I could miss a bug like the Debian OpenSSL one that would make the whole thing moot. WinRAR is closed source and I have no idea what it's doing (but there's no particular reason not to trust it). -- BenRG (talk) 16:07, 16 July 2013 (UTC)

How can I google the earliest something?

For example, I want to know where on internet did some text first appear. I see there are some option to filter results by time like the past day/hour/week, but are there an option of findind earliest instances? --128.237.207.243 (talk) 21:27, 15 July 2013 (UTC)

I don't think you can do this with google's regular web search web searches but you can with books and news searches (and you can assume that the earliest in print of most things will be from books or newspapers anyway). Both are available from the "advanced" search options of each of them, at the bottom of the page. For books you just choose a date range, so you can put in 1700 to 1850, and then narrow if that brings up too many. For example, [3 results for "flintlock" from 1700 to 1750 http://www.google.com/search?tbo=p&tbm=bks&q=flintlock&tbs=,cdr:1,cd_min:Jan+1_2+1700,cd_max:Dec+31_2+1750&num=10]. For google news you have to choose the "archive" from advanced and then can do the same thing. I missed the part about the search being about the first to appear on the Internet.--108.46.106.40 (talk) 01:42, 16 July 2013 (UTC)

[ec] search tool are you using? Presuming you are using Google, when you set the filter for a specific time range, it theoretically gives you the results that were published within that range. However, it depends on what you are looking for. Google hasn't always existed (well less than have the lifespan of the internet and maybe about have of the life of the web), so the earliest instances of whatever you are looking for might not be in their archives. Mingmingla (talk) 01:44, 16 July 2013 (UTC)

That filter only goes back one year, though; and I bet the OP is looking for entries older than that... I don't think this is possible. --Yellow1996 (talk) 16:10, 16 July 2013 (UTC)

If you have narrowed it down to a few pages you suspect may be the original you can check them on the Wayback Machine: [3]. It will let you see how a site has changed over time, so you can see when the text was added. 209.131.76.183 (talk) 17:12, 16 July 2013 (UTC)

July 16

Recommendation for a fast disk burner?

My external burner just went kaput. I now want to get a new one, but wanted to know if anyone can recommend one that will be faster. Willing to spend extra for the speed. The one that just died was an LG Portable Super Multi Drive, model GP10NB20 and I bought it randomly off the Internet (not complaining; it was a workhorse, I used it a ton, and it was very cheap). But I want something really fast. Must work with a mac, which is what I have. Any ideas?--108.46.106.40 (talk) 01:29, 16 July 2013 (UTC)

The GP10NB20 appears to be a DVD writer and DVD writer speed is basically irrelevant nowadays for internal burners. I suspect it's the same for external ones. I would worry more about writing quality and media compatibility (of course if you always use specific media like MCC004 or something, only compatibility with that media matters) than anything else although the relative unpopularity amongst experienced users and extreme commodity nature of burners nowadays means from what I say last time I looked, actual data on these is far harder to come by nowadays. Nil Einne (talk) 02:42, 16 July 2013 (UTC)

Regular expression to convert C code braces to indentation

Is is possible to convert C code braces to indentation using regular expressions? Czech is Cyrillized (talk) 03:17, 16 July 2013 (UTC)

Yes, depending on the nesting, it could be quite simple. If you could define the C code brace standard you're talking about that'd be a start. Most C code has a rough formality to it, but not to the point where you oculd assume there's some universal method. Shadowjams (talk) 06:23, 16 July 2013 (UTC)

I presume you are looking to pretty up C code by fixing the indentation. Many integrated development environments you might use to develop your code, includes tools to tidy up the code indentation. If this is the purpose, it could be considerably easier then trying to write your own code tidy-er. Astronaut (talk) 11:30, 16 July 2013 (UTC)

Regular expressions could be the magic wand, but if you don't want a few nasty bugs and don't want to use a Rosetta Stone after a few years to find out what the programmer actually meant, about 5 lines of code in any language would fix that for you. Joepnl (talk) 20:47, 16 July 2013 (UTC)

How to hide watched YouTube videos from search results?

Hi, every few days I'm searching for videos on a certain topic (squash games if you're interested...). Most of the times I'd like to watch videos I haven't watched before, however YouTube displays the same videos over and over again for the search.

Is there any browser extension or another method that gives an option to hide the already watched videos (e.g. the ones in my history list)? Gil_mo (talk) 04:10, 16 July 2013 (UTC)

This Google Chrome extension apparently does this. Good luck! --Yellow1996 (talk) 16:14, 16 July 2013 (UTC)

Live exchange rates into a spreadsheet

Is there any way to get the Google exchange rates or other reliable exchange rates into a spreadsheet so that it will update daily online? Without slowing the computer down, encountering malware, or other disadvantages? Thanks. Itsmejudith (talk) 12:01, 16 July 2013 (UTC)

• Google Drive spreadsheets have a function "ImportHtml(URL, query, index)" that pulls data from a web page into the spreadsheet. The "Query" field is "table" or "list" and the index is just an integer. Trial and error will find the data you need. "=ImportHtml("http://www.x-rates.com/table/?from=USD&amount=1", "table", 0)" extracts a table of exchange rates from x-rates.com. Google drive spreadsheets seem to be based on OpenOffice.org's spreadsheet "Calc". Richard-of-Earth (talk) 19:10, 16 July 2013 (UTC)

Thanks. I'm working in Excel at the moment but presumably can open my existing spreadsheet in Google Drive. Will have a go. Itsmejudith (talk) 20:00, 16 July 2013 (UTC)

Need a freeware spreadsheet

I urgently need to enter some data in a simple spreadsheet, but the Excel spreadsheet on the notebook I have to use in the field is "locked up" because they lost the "product key" so it was never verified as being on the computer when it came out of the box. So basically I need a spreadsheet program on which I can enter several hundred rows of data with perhaps six columns, the data consisting of numbers and text in different columns, and then sort based on some of the data fields. I need to be able to export the data to a thumbdrive in some simple format like comma delimited ASCII and then I would like to be able to import it to legit Excel programs on other computers. I do not need any whistles and bell like formulas, graphs, charts, or fancy fonts and other razzle-dazzle formatting. The first Google Search result for freeware spreadsheet is "Kingsoft Spreadsheets Free 2012 (8.1.0.3030)" Are they a trustworthy software provider, or has someone found a better freeware spreadsheet? (I don't want to download a trojan horse or virus, or glitchy software which loses my input efforts.). Thanks. Edison (talk) 15:15, 16 July 2013 (UTC)

LibreOffice-Calc or its close relative OpenOffice-Calc are free and open source; they're fairly heavyweight (they're pretty much on par with Excel). Or you can use Google Docs online, assuming the field in question has internet access. -- Finlay McWalterჷTalk 15:44, 16 July 2013 (UTC)

Thanks for the recommendation. LibreOffice-Calc was easy to download and more than satisfies my needs. Mark this one "Resolved." Edison (talk) 16:48, 16 July 2013 (UTC)

Resolved

Allow me! :) --Yellow1996 (talk) 16:58, 16 July 2013 (UTC)

How can I prevent image links from grabbing my information?

For example http://www.ipnow.org/ receives much information and generates a picture. If someone post an image of this site somewhere I guess I would sent my IP and all kinds of information there once I see the image.

I just found changing user agent by developer tools in Chrome and IE, but I needed to change the user agent every time I open a new window, is there a way to configure user agent once and for all?

I guess prevent my computer send information to those sites would be a easy way--just change the hosts will do that. Just ask: is the hosts way 100% secure?

In addition, which infomation in http://www.ipnow.org/ must be send to see the website? How can I remove unnecessary information such as "You Came From: "?--128.237.207.243 (talk) 20:45, 16 July 2013 (UTC)

• "You came from" is derived from the HTTP referer header; you can disable that (e.g.) in Chrome by doing this.
• Details about your browser and OS are from the User agent header; you can find plugins for every modern browser - google for "firefox user agent switcher" etc.
• Other stuff (your IP, isp details) they get from the TCP connection; TCP wouldn't work without that stuff. You can use an HTTP proxy or a virtual private network; but then the proxy or VPN knows about every site you visit.

None of these things are "unnecessary information", and expect to break things when you start to disable browser features like this. -- Finlay McWalterჷTalk 21:01, 16 July 2013 (UTC)

Can I prevent the site from getting my plugin information (http://www.ipnow.org/plugins.php)?--128.237.207.243 (talk) 21:14, 16 July 2013 (UTC)

How about the language info? I don't see that in the user agent header, so where does it come from?--128.237.207.243 (talk) 21:19, 16 July 2013 (UTC)

Besides User agent header, are there anything different in browsers that help a system identify what the browser is?--128.237.207.243 (talk) 21:25, 16 July 2013 (UTC)

The browser can be identified client-side by Javascript through various means. There are also various bugs that can be used to hide some stuff from various browsers, and Internet Explorer has conditional comments which could all conceivably be used to identify the browser server side - Javascript fairly easily through direct communication to the server, the others by having some files load only under some circumstances.

You can use Proxomitron to look at your outgoing HTTP request and see what kind of information is sent and received, and to modify any header you'd like in various ways. There may be more recent software that does the same thing. 64.201.173.145 (talk) 23:33, 16 July 2013 (UTC)

Possible meanings of '**'

Hello, I've been handed some code snippets in an unknown language. The confusing part looks like this:

HEIGHT=(4+EXP(3+(-1.5)*(DBHI**-0.6)))*0.3;

It seems that ** is either a unary operator, or perhaps the relevant string is '**-'? My first guess was that it represented a unary "squaring" operator, but that must be wrong (Height should be non-decreasing in DBHI). I'm also fairly sure this code is correct, in some language. Any suggestions? Thanks!

SemanticMantis (talk) 21:57, 16 July 2013 (UTC)

** is the exponentiation operator in Pascal, so DBHI^-0.6

But Pascal uses := for "becomes equal", so you'd expect it to be HEIGHT:=(4+EXP(... -- Finlay McWalterჷTalk 22:06, 16 July 2013 (UTC)

It's also exponentiation in Python, which uses the C-like = for "becomes equal" -- Finlay McWalterჷTalk 22:08, 16 July 2013 (UTC)

You'd also need to know what the EXP function is; presumably EXP(x) means e^x . Python's EXP function (math.exp) is almost always spelled lower case. So your code may be old Fortran (e.g. FORTRAN 77) which was back when FORTRAN still used lots of CAPITALS for things and FORTRAN programs read like lists of demands from the bossy computer in The Forbin Project. Again ** is exponentiation in FORTRAN77, and EXP(x) is e^x in FORTRAN77 ref. -- Finlay McWalterჷTalk 22:26, 16 July 2013 (UTC)

Yes, FORTRAN 77 is a likely candidate, and also seems to explain the odd CAPS as well as **. Thanks! I'll have to wait until tomorrow to see if that interpretation produces the expected/reasonable output. SemanticMantis (talk) 22:43, 16 July 2013 (UTC)

That is Fortran and means "to the power of", so it means DBHI^-0.6. Bubba73 ^{You talkin' to me?} 22:55, 16 July 2013 (UTC)