Wikipedia:Reference desk/Archives/Computing/2010 May 11

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May 11

TI-89 Titanium

I have a TI-89 Titanium calculator. I am wondering what keystrokes is necessary to convert

$({\sqrt[{3}]{\frac {x}{y^{7}}}})$ to ${\frac {({\sqrt[{3}]{x*y^{2})}}}{y^{3}}}$.

Whenever I pass it through the calculator I get ${\frac {x^{\frac {1}{3}}}{y^{\frac {7}{3}}}}$. I use the keystrokes root((x/y^7),3). I need help!!! --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 01:27, 11 May 2010 (UTC)

The calculator's answer is correct, even if somewhat unhelpful. Probably, its built-in simplifier prefers the form that doesn't have the root. I don't believe that you can change the way the simplifier works. (This forum post seems to agree.[1]) Essentially you and the calculator are not agreeing on what form is "simplest". You could work it out on paper, it's pretty straightforward. APL (talk) 02:18, 11 May 2010 (UTC)

That's right: the calculator algorithm separates the powers of x and y. Educational mathematics has a "rule" that there should be no root in the denominator. They are just different views of "simplest". Do you need help in converting one to the other, or were you just wanting the calculator to perform the conversion? Dbfirs 07:38, 11 May 2010 (UTC)

I know ow to do it manually but I was just wondering if the calculator can do it faster for me... --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 16:07, 11 May 2010 (UTC)

PC won't recognize camera anymore

I've got a Canon PowerShot A95 from which I normally load pictures into my Dell Inspiron 6400 running Windows XP. In the past, I had no problem transferring the pictures from camera to PC. I haven't done so in the past few months, but I tried to do it today, and it wouldn't recognize my camera. So I went into Control Panel to try and manually add my camera as a device, and my model isn't on the list. What gives? 24.189.90.68 (talk) 04:46, 11 May 2010 (UTC)

No idea offhand, but here's a possible workaround: Go get a standalone card reader for the memory card. Shouldn't cost more than twenty bucks. Take the card out, put it in the reader, and hook that up to the computer. You should see a new drive show up in "My computer".

I admit it's a pity to waste the sawbuck if you don't have to, but a standalone reader has its advantages (doesn't drain your camera batteries, doesn't try to go through obnoxious proprietary software provided by the camera company). --Trovatore (talk) 04:49, 11 May 2010 (UTC)

Any recommendations on which particular brand of card readers would be of best quality? 24.189.90.68 (talk) 05:21, 11 May 2010 (UTC)

Even the really cheap ones (less than £5 in UK) seem to work OK, though there might be a speed difference. Does the Canon website have a download for a Powershot A95 driver, or did a CD with a driver come with your camera? Dbfirs 06:28, 11 May 2010 (UTC)

The camera previously belonged to a friend of mine, so I honestly don't know if it came with a CD and/or a driver or not. As for any downloads, I went to their site, and there are some software updates, as well as a driver update for my OS released in 2006. 24.189.90.68 (talk) 08:47, 11 May 2010 (UTC)

For what it's worth, PowerShot cameras expose themselves as some sort of image acquisition device over USB, which requires special software to access the images (unlike some other camera brands which act like memory card readers, which is a lot more convenient). The camera should at least show up in My Computer, though. -- BenRG (talk) 09:54, 11 May 2010 (UTC)

My PC used to recognize it like a normal USB device, so I can't understand why that changed all of a sudden. I haven't updated my drivers since I last uploaded pictures from my camera, so it can't be an incompatibility issue. 24.189.90.68 (talk) 10:05, 11 May 2010 (UTC)

This forum post suggests that the camera decides whether to be a USB mass-storage device class or USB video device class object depending on the setting of the "playback" switch (presumably the little triangular "play" icon) when the USB connection is made. -- Finlay McWalter • Talk 11:54, 11 May 2010 (UTC)

Right, I'll second Finlay McWalter's statement: on a PowerShot you are supposed to move that switch to the little triangular "play" icon before you plug it in. If this still doesn't work, I'd use a memory card reader as suggested above. Comet Tuttle (talk) 16:33, 11 May 2010 (UTC)

addEventListener

In theory, can the DOMNode::addEventListener() method be expected to work properly if called on a node before the node is added to the document? Is cloneNode(true) supposed to preserve event handlers? NeonMerlin 05:24, 11 May 2010 (UTC)

It will help if you specify your programming language and/or environment. Commmonplace libraries in C++, Java, C#, Javascript, and thousands of third-party libraries have functions called "addEventListener()" - judging by your syntax, it appears you mean a C++ version. Can you specify? Nimur (talk) 07:01, 11 May 2010 (UTC)

No, I mean the one JavaScript uses from the W3C DOM specs. I'm only using the C++ syntax because AFAIK the class name isn't visible to JavaScript (which, given that class names are present in the DOM specs, suggests to me that the DOM is designed for multiple languages). NeonMerlin 08:11, 11 May 2010 (UTC)

From the Mozilla Documentation Center: addEventListener() works on any DOM element, even non-visible ones. It should be okay to instantiate a node and add a listener before adding the node to the document. The Node.cloneNode() documentation doesn't specify an answer to your second question, but it seems plausible that the actionListener would be added to the clone (but would not be cloned itself). This is worth testing. Nimur (talk) 13:33, 11 May 2010 (UTC)

Software To Monitor Fan/Temperature On Ubuntu 10.04

Does anyone know of any software I can get which will allow me to monitor the fan on my Acer Aspire laptop running Ubuntu 10.04? The only monitors I am able to find in the Software Centre are for CPU, disk space, and a few other things, all of which are already available in System>Administration>System Monitor. I am hoping for a desktop widget or something. Cheers. --KägeTorä - (影虎) (TALK) 11:06, 11 May 2010 (UTC)

The package lm-sensors installs the program sensors (and the setup utility sensors-detect) which reports the information provided by all the sensors it finds (sensors-detect leads you through all the different busses it can scan, and then shows what it discovers; I think the package install scripts actually run this for you, but you can run it yourself to see what it tries). You can monitor the results reported by the detected sensors by running sensors yourself or from a script, installing sensord which logs these to syslog, or installing xsensors which shows the results reported by sensors in a GUI window. There are probably Gnome and KDE widgets that do likewise. I don't know about the Aspire, but this finds two (unnamed) temperature sensors in my Acer Travelmate. - Finlay McWalter • Talk 11:51, 11 May 2010 (UTC)

Ah, the gnome applet is just called the Gnome sensors applet. It's in package sensors-applet. In addition to the stuff reported by sensors, it also talks to the proprietary nVidia driver, to the kernel ACPI module, and gets hard disk temperatures from hddtemp using SMART. -- Finlay McWalter • Talk 12:02, 11 May 2010 (UTC)

And the KDE application is Ksensors -- Finlay McWalter • Talk 12:11, 11 May 2010 (UTC)

Excellent! Cheers! I'll try that out a bit later on, then (different computer at the moment). Thanks! --KägeTorä - (影虎) (TALK) 12:17, 11 May 2010 (UTC)

Update: Well, I've downloaded and installed them, and when I try to run them, nothing actually happens. I've followed the instructions on the websites but still no joy. Cheers anyway. --KägeTorä - (影虎) (TALK) 15:31, 11 May 2010 (UTC)

On my desktop, sensors doesn't find any usable sensors, but the gnome applet (which you have to add to the top panel) shows GPU and disk temperatures. On my laptop it does find the two motherboard temps, and gnome applet finds the two cpu temperatures and the disk temperature. But if sensors doesn't know about the various chip sensors in a given laptop, it can't know how to interrogate them, and so shows nothing useful. -- Finlay McWalter • Talk 15:59, 11 May 2010 (UTC)

GKrellM 129.67.37.143 (talk) 16:33, 12 May 2010 (UTC)

XP won't shut down

Hi my PC refuses to shutdown, a quick google search throws up a lot of guff about using registry cleaners to fix the problem, I am not a fan of theses tools anyone got any ideas what I can do? Thanks Mo ainm~Talk 12:15, 11 May 2010 (UTC)

Does it shut down if you initiate the shutdown from the Task Manager? Hit ctrl-alt-del, then from the Task Manager window, go to the "Shut Down" menu, then choose "Turn Off" (or Restart, or whichever other option you want). I have found that this sometimes works in situations where Explorer in Windows XP refuses to acknowledge the "Shut Down" command from the Start menu. Comet Tuttle (talk) 16:31, 11 May 2010 (UTC)

You can also shut down the PC from a command prompt. Just enter the command

shutdown -s -f -t 00

and the PC will shut down. The command "shutdown -s" can even be entered from the start menu (in the "Run" box). --NorwegianBlue ^talk 20:46, 11 May 2010 (UTC)

I think the OP is actually asking us if there is any way to fix the problem and stop it from happening again. If they were asking about how to switch it off then we could point them to the OFF button as a last resort. I can't help, because you haven't given us enough information about the problem, but I thought I should just point this out for anyone who can. --KägeTorä - (影虎) (TALK) 00:21, 12 May 2010 (UTC)

I tried ctrl alt del and it would not turn off or even restart, the only way I could turn it off was to hold the power button. I haven't tried from the command line, but it is not really a preferred option to have to use this way (if successful). Would like to know a possible cause so I can fix it. I have added no new hardware of software and my Kaspersky AV throws out no infections. Mo ainm~Talk 08:54, 12 May 2010 (UTC)

Assuming you do not in fact have any viruses (which can still happen even if your current AV solution does not pick up on it, but I'll agree it seems unlikely), you may want to run a Windows Repair. Back up your important data first. The Repair process does not wipe your data however it's better to be safe than sorry. Be sure you have your Windows key handy before you do this. If this does not work, you might need a full OS reinstall. Amordea (talk) 11:15, 12 May 2010 (UTC)

Paste text greasemoney

Resolved

I want to write a greasemoney script that can paste a pre-written body of text into a text box. I would like it to function by right clinking in a text box, and in the menu that appears there's an option like "paste text" or something. Is this possible to do? I'm a noob at greasemonkey 82.44.55.254 (talk) 13:44, 11 May 2010 (UTC)

AFAIK the only way to change the right-click menu with GM is to completely replace it, which you probably don't want. Perhaps it would be easier to add a little "paste the canned text" button next to the text box, or something like that? --Sean 18:50, 11 May 2010 (UTC)

Yes that would be ok. How could it be done? 82.44.55.254 (talk) 19:33, 11 May 2010 (UTC)

The following does it:

// ==UserScript==
// @name           TestTextArea
// @namespace      http://aaa.com
// @include        http://svnback.bustech.com/bugzilla/show_bug.cgi*
// @require        http://jqueryjs.googlecode.com/files/jquery-1.3.2.min.js
// ==/UserScript==

var canned_text = "my canned text";

jQuery('textarea')
  .each(function(idx) {
        var textarea = jQuery(this);
        var button = "<a href='#'>{INSERT}</a>";
        textarea.before(button);
        textarea.prev().bind('click', function(event) {
            event.preventDefault();
            textarea.val(canned_text);
        });
        textarea.before('<br>');
  })

--Sean 15:47, 12 May 2010 (UTC)

Thank you! <3 82.44.55.254 (talk) 20:04, 12 May 2010 (UTC)

Is a search box to the upper right "intuitive"?

Hi. I know this is not the best place to discuss the WP Beta, but I'm looking for opinions from knowledgeable Internet users. My question would be, is having the search box at the upper right hand corner of a web page "intuitive" as the Beta project claims it is? The project claims that "The new position takes advantage of user expectations from across the web". Please correct me if I'm wrong, but for any major website other than Wikipedia, you browse the site by links and whatnot, and only occasionally use the search box. That's why most websites put their search box, say, in the upper right-hand corner, for instance: so that it's for the most part out of the way, because searching is a secondary function for those websites. But for Wikipedia, this is not the case! Wikipedia's main browsing tool is the Search Box! Therefore, changing the search box to the upper right, in order to "align Wikipedia with many other major websites" [2], is not really a good enough justification, or is it?

I think it's also important to keep in mind that us westerners read from left to right; therefore, the most important elements of a website should be closer to the left than to the right, for easy and fast access, right? So, does moving the search box from the left to the upper right retain the search box's importance, or does it make it a hindrance to look for the search box in such a cumbersome place in the web page? Is it really a good thing to put the search box, the main browsing tool for WP, as if it were a secondary thing like in other websites? (They say they got good results on the new position of the search box in their research tests, but it seems they only tested 8 people, so that doesn't make sense to me either.)

Wikipedia is NOT like other major websites, because unlike other websites, Wikipedia's search function it's its main function! This is why I think there should be more prolific discussion about this particular issue more than anything else, especially before the big change is invariably forced upon everyone. Kreachure (talk) 13:47, 11 May 2010 (UTC)

You're right. This is not the place for such a discussion, nor for airing your views on the proposed new wikipedia skin. --Tagishsimon (talk) 13:57, 11 May 2010 (UTC)

This would probably be better suited for Wikipedia:Village pump (development), or perhaps the miscellaneous village pump page. Buddy431 (talk) 15:15, 11 May 2010 (UTC)

Fine. I was looking for widespread discussion from buffs and experts (like the ones I usually find here), about a common subject that experts and non-experts could relate to; not technical discussion about technical issues at pages only technical users use. But I guess that if no one's all that interested in the discussion about their own website, then I shouldn't care either. Good times! Kreachure (talk) 15:35, 11 May 2010 (UTC)

It's not that we aren't interested (I don't like it much either and personally will choose the old UI) but that, as stated at the top of the page, the Reference Desk isn't a discussion forum; and although we at the Reference Desk are extremely powerful and influential, our levels of power and influence rapidly wane as you leave the Reference Desk pages, and the levels reach a value of 0 when landing on any other Wikipedia page, including those where it's appropriate to have this conversation. Comet Tuttle (talk) 16:46, 11 May 2010 (UTC)

And any claim to academic discussion is undermined by your polemic last paragraph. --Tagishsimon (talk) 16:47, 11 May 2010 (UTC)

Are you talking about the paragraph where I said that the search function is the most important function in WP, and then I said that the change will be forced upon everyone as a standard (on May 13)? I don't get what's polemic about that. Kreachure (talk) 16:55, 11 May 2010 (UTC)

Was there some ambiguity about "last paragraph" phrase"? Some lack of polemic in the upper case "NOT"? In the plea for more discussions (read the guidelines at the top of this page...)? In the "big change is invariably forced" phrase? It's fair enough that you don't like the change. Hijacking the RD to complain about it is not on. It would have been perfectly possible for you to ask the question in a neutral fashion. You chose not to. Your bad. --Tagishsimon (talk) 17:13, 11 May 2010 (UTC)

I think people are getting side tracked from the core question OP asked; "Is a search box to the upper right "intuitive"". 82.44.55.254 (talk) 17:28, 11 May 2010 (UTC)

The sidetracking was from the original poster, for what it's worth, who is looking for "widespread discussion from buffs and experts". Comet Tuttle (talk) 17:42, 11 May 2010 (UTC)

I haven't tried beta here on en.wiki but from what I've seen at the commons it looks awful, clumsy and unnecessary. And I agree with you that the new placement of the search box is stupid too. Wikipedia currently has a simplistic, easy to use interface that's so perfect for it's function that this change seems like the wikimedia foundation meddling because they were given a big donation and have nothing better to do with the money. 82.44.55.254 (talk) 15:49, 11 May 2010 (UTC)

See Wikipedia:Village pump (technical)#Browser size (permanent link here). -- Wavelength (talk) 16:02, 11 May 2010 (UTC)

To try and answer the question about whether the search box at the top is intuitive, as a brief exercise I went to alexa.com's Top Sites page and looked at the first few of the Top 10 web sites to see where their search boxes are, and found:

• Google: Front and center (web page is built around it)
• Facebook: No search field on home page, but login fields are at top
• YouTube: Top
• Yahoo: Top
• Live.com: Top
• Wikipedia.org: Left side
• Baidu.com: Front and center (web page is built around it)
• Blogger.com: No search field on home page, but login fields are at top
• Msn.com: Top
• QQ.com: Top

I know this doesn't equal "usability", but it's reasonable to suggest that if 7 of the other top 8 websites (excluding the two that are basically a big text field with some elements placed around it) have their primary text fields at the top of the page, that Internet users are being conditioned to look for the text fields at the top of the page. Comet Tuttle (talk) 17:42, 11 May 2010 (UTC)

Add to that the top-right placement of the browser search bar in most modern web browsers (well IE, Firefox and Safari at the very least, and I assume others).131.111.185.68 (talk) 22:02, 11 May 2010 (UTC)

(EC with above) In addition most modern browsers have a search bar. In fact it isn't just browsers but many programs including the OS themselves. Guess where that is by default? (The reason is of course partially related to the UI.) I also happen to be on eBay, DealExtreme [3] and [4] at the current time. Guess where their search bar is? Yep at the top (albeit mostly centre not right.)

I agree with others that this is the wrong place, and is a bit silly when it starts off with unproven claims like

Wikipedia is NOT like other major websites, because unlike other websites, Wikipedia's search function it's its main function

Personally I use search functions on other websites much more then wikipedia. Perhaps that's just me, I don't claim to be an average user (although do think that for a number of examples both me and CT have mentioned search would be important), but I also don't see any evidence presented for this claim and if a large chunk of your argument is apparently unsupported by any actual data, it usually falls flat on its face. When you've apparently failed to consider other obvious things as CT and me have IMHO amply demonstrated well then...

To put it a different way while I can't comment on their performance in particular, I'd trust professionals paid to do the job much more then I would some random person who makes a random OT complaint based on premises without any evidence and without even apparently considering some rather obvious issues. But perhaps that's just me.

P.S. If I'm not mistaken the WMF was given money specifically to improve usability. They obviously could have rejected that money OR tried to convince the donator to let them do other things with it (I don't know if they tried but I wouldn't be surprised if they didn't) but clearly whether or not they had anything better to do with it didn't come in to it. Someone specifically wanted them to improve usability and paid them to do it whether or not other people feel it's a worthwhile goal (and frankly I doubt they cared much about the opinions of former vandals).

I should also add that the opinions of 'knowledgeable Internet users' is unlikely to be what the WMF cared much about. These sort of people should be able to find the search box wherever you place it and more importantly are only a tiny proportion of people that use the website. In fact any discussion which tries to collate anything from the experience and expectations of wikipedia editors, and the small subset of editors that edit any specific page at that is inherently flawed. The vast majority of readers aren't editors. I believe one of the goals of the usability initive was to get more editors, so clearly finding ways to get more editors was important (although that still means trying to get something from existing editors is not necessarily the most productive avenue) however I'm pretty sure it wasn't the only goal and the location of the search bar in particularly is something everyone including readers may want to use. In other words, the knowledge and experience of web designers and others familiar with relevant research etc may be useful, but the knowledge of random editors based primarily on their personal experience much less so.

Nil Einne (talk) 22:39, 11 May 2010 (UTC)

Another interesting thing. The first result on Google for me for 'search box location' is [5] which says "There are many possibilities, but only a couple of right ones. The most convenient spot for users would be the top left or top right of every page on your website, where users could easily find it using the common F-shaped scanning pattern." It also mentions the old wikipedia search box as a bad design albeit not because of the location. (The first result on Bing is [6] which is of limited use to this discussion although guess where their search box is located?) Nil Einne (talk) 19:02, 13 May 2010 (UTC)

See Home Page Usability and Credibility Survey - Fortune 30 versus Inc. fastest growing companies; it might have some relevance here.

-- Wavelength (talk) 22:56, 11 May 2010 (UTC)

I think it was better where it was before. You didnt have to drag your cursor from one side of the page to another. The box and other things you might want to click on were in the same place. Nor do I like the grey shading and blue lines on pages - again the previous version was better. I vote for reversion. 78.149.199.79 (talk) 15:05, 16 May 2010 (UTC)

Using keyboard as a mouse on a laptop without numlock

Hi there, all:

My laptop has recently broken down overnight, with the OS disappearing. I'm using a friend's old laptop until I replace or repair my laptop, but unfortunately, it too has problems. Many of them I have solved myself, such as the incredible amount of scareware, but one big problem remains - the functionality of the touchpad comes and goes. At some points, it works like any other, without a hint of a problem; for hours at a time, though, it is stuck in one of two phases: either completely non-responsive, or jutting around and failing to click anything other than what one does not want to click.

I thought of finding a program to temporarily solve this, with which one could scroll the mouse across pages using keyboards. However, all of the ones that I have encountered rely on there being Numlock or a separate numbers keypad, neither of which this laptop has. Can anyone help with a way to scroll using a keyboard, without numlock?

All the best &c —Preceding unsigned comment added by 82.36.198.62 (talk) 17:49, 11 May 2010 (UTC)

Why don't you just connect an actual mouse to it? Theresa Knott | token threats 05:23, 12 May 2010 (UTC)

• Hello. I thought that folk would surmise that there was a reason why I should choose the rather more cumbersome method of using a keyboard rather than attaching a mouse - the USB slots do not work. All the best, &c. --82.36.198.62 (talk) 08:18, 12 May 2010 (UTC)

Touchpad is "touchy" and USB slots don't work? Hmmm. You mentioned "scareware" in which case I'd strongly suspect a heavy virus infection (when you see one roach, you know there's bound to be many more hiding nearby). This could have done damage to your drivers or other system software components, which could account for the intermittent failures. You may need to reinstall these (via driver reinstall and Windows repair/reinstall respectively). Amordea (talk) 10:24, 12 May 2010 (UTC)

• Thanks for your suggestion; I'll try that right away! --82.36.198.62 (talk) 11:20, 12 May 2010 (UTC)

Compress

I have 500 files that I want to compress with 7zip individually ie into a separate .7z archive for each file. Is there an option to do this with 7zip? Thanks 82.44.55.254 (talk) 19:24, 11 May 2010 (UTC)

On sh/cygwin find directory -type f -exec 7z a {}.7z {} \; -exec rm {} \; will compress every file in directory and its subdirectories. find directory -type f -exec 7z x {} \; -exec rm {} \; to decompress. --194.197.235.240 (talk) 21:14, 11 May 2010 (UTC)

Thanks but I'm not on linux / can't install the cygwin thing for windows. I was asking if there was a way to do this with the 7zip Windows gui 82.44.55.254 (talk) 21:58, 11 May 2010 (UTC)

7-Zip on Windows has a number of command line options. When I entered "7z -?", I got this:

7-Zip command line options

7-Zip 4.57  Copyright (c) 1999-2007 Igor Pavlov  2007-12-06

Usage: 7z <command> [<switches>...] <archive_name> [<file_names>...]
       [<@listfiles...>]

<Commands>
  a: Add files to archive
  b: Benchmark
  d: Delete files from archive
  e: Extract files from archive (without using directory names)
  l: List contents of archive
  t: Test integrity of archive
  u: Update files to archive
  x: eXtract files with full paths
<Switches>
  -ai[r[-|0]]{@listfile|!wildcard}: Include archives
  -ax[r[-|0]]{@listfile|!wildcard}: eXclude archives
  -bd: Disable percentage indicator
  -i[r[-|0]]{@listfile|!wildcard}: Include filenames
  -m{Parameters}: set compression Method
  -o{Directory}: set Output directory
  -p{Password}: set Password
  -r[-|0]: Recurse subdirectories
  -scs{UTF-8 | WIN | DOS}: set charset for list files
  -sfx[{name}]: Create SFX archive
  -si[{name}]: read data from stdin
  -slt: show technical information for l (List) command
  -so: write data to stdout
  -ssc[-]: set sensitive case mode
  -ssw: compress shared files
  -t{Type}: Set type of archive
  -v{Size}[b|k|m|g]: Create volumes
  -u[-][p#][q#][r#][x#][y#][z#][!newArchiveName]: Update options
  -w[{path}]: assign Work directory. Empty path means a temporary directory
  -x[r[-|0]]]{@listfile|!wildcard}: eXclude filenames
  -y: assume Yes on all queries

I've not actually tried this, but I'm pretty sure you could use this information to make a .bat file perform the same compression task on 500 files and make 500 .7z files (remember "dir > filelist.txt" will output the result of a dir command to a file rather then the screen). Astronaut (talk) 16:01, 12 May 2010 (UTC)

Assuming 7z.exe is in your path:

       for %d in (*) do 7z.exe a "%d.7z" "%d"

--NorwegianBlue ^talk 20:56, 13 May 2010 (UTC)