Wikipedia:Reference desk/Archives/Computing/2015 March 5

= March 5 =

Excel tables
Let's say that I have a defined table in Excel, with five columns and 1,000 rows. The cells are all filled, but let's suppose that one column is composed of the outputs of a formula (for example, the cells in column C add the values in columns A and B). For whatever reason, I want those values to remain static, so I do a copy-paste special (values), one of the first tricks you learn with Excel. What I've noticed and what I'd like to understand better is that sometimes Excel will stop this from happening, by claiming the selection lies both within and outside a table. I can work around this by carefully highlighting only cells C1:C1000, but it's obviously much faster to right click on the whole column at once. The frustrating thing is that it only does this sometimes. Sometimes I can highlight the whole column and copy-paste while other times I am prevented. Is there something I can do or some setting in the table that allows/prohibits this? Matt Deres (talk) 16:54, 5 March 2015 (UTC)
 * Copy the cells and reinsert (see small pulldown arrow right side of the paste button) values only. -- Hans Haase (有问题吗) 08:48, 6 March 2015 (UTC)

When is a URL not a URL?
I asked a similar question several years ago when I discovered that I could not use the URL of my source because I got to the source from the URL shown at the top of the screen only after clicking somewhere.

This is similar. If you go here and then click on the first link, you end up here. But if you go here and click on the first link, you also end up here. But it's not the same page.— Vchimpanzee  •  talk  •  contributions  •  19:04, 5 March 2015 (UTC)


 * Back in the early days of the web, a URL was essentially the name of the computer plus the name of the file on that computer, relative to some top level folder like /var/www or something.


 * These days, while that might often still be true - it's really little more than a text string that goes to a piece of software that delivers some data. The software can more or less do what the heck it likes with that text string - so more or less any behavior is possible.


 * In this specific case the ".cfm" extension on the URL is a clue. It stands for ColdFusion Markup Language - which indicates that the file is not an HTML document - it's more like a Wikipedia page where the data in the file is converted, modified, mangled - by some piece of software (in this case, Adobe ColdFusion).  That software may choose to interpret the URL in any way it likes - including giving you different content depending on where you clicked it from - or depending on whether you have a cookie installed - or where in the world your IP address geolocates to - or what kind of browser you're using.


 * Interestingly, if you go to another computer (or open a different browser on the same computer) so that ColdFusion doesn't know where you came from - then type in "http://www.theminipage.com/arch/news.cfm" directly - then you get an error message: "Invalid Archive Edition Request. Please try your request again."..and a blank page when you hit "OK".  This seems like an especially stupid way to build a website because I may see the page about cats - copy the URL and email it to a friend.  Instead of seeing the cat page, they'll see the error message.   This has other ramifications if Google is 'spidering' the web site to index it.  The confusion about what data content is at that URL will completely screw things up - which makes it harder, and perhaps impossible, to find that page in a search engine.


 * That's just poor web design...but it's not illegal. (HINT: Don't use ColdFusion!)


 * There are certainly legitimate cases where you want to do this. One obvious one is when you have to create an account and log in to get to certain content.  In that case, you don't want someone with a legitimate account to be able to copy-paste and email the URL and thereby allow non-members of the site to see that content...instead, accessing that URL might direct you to a "Login/Register" kind of page instead.


 * SteveBaker (talk) 21:19, 5 March 2015 (UTC)
 * I can say that I used to access this content through The Houston Chronicle. Then I couldn't. I tried to get to it another way and was given a "members only" type of message. Since I couldn't see some of the content in my local newspaper (in the actual newspaper) I asked for a way, and this is the way I get there now. I put the link in the Mini Page article, but now I'm wondering if I should have.— Vchimpanzee  •  talk  •  contributions  •  21:39, 5 March 2015 (UTC)


 * Server-side dynamic web pages are essentially as old as the web. The &lt;isindex&gt; tag dates to early 1991 and CGI dates to 1993, when there were ~100–1000 web sites in the whole world . -- BenRG (talk) 02:47, 6 March 2015 (UTC)


 * It's using a cookie (or some form of cookie-like local storage) to choose the edition. I know that because if I open the first link and click "Home" (getting the Feb. 28 edition), then open the second link in a second tab and click "Home" (getting the Feb. 14 edition), then reload the first tab, the first tab shows the Feb. 14 edition. This is unusual and, as SteveBaker said, a bad idea. -- BenRG (talk) 02:47, 6 March 2015 (UTC)
 * I suspect from the other replies, that it is using the HTTP Referer to detect which webpage you came from to reach that page, and then creating content based on that. LongHairedFop (talk) 10:46, 6 March 2015 (UTC)
 * My two-tab test shows that it's not the referrer. -- BenRG (talk) 19:50, 6 March 2015 (UTC)
 * The cookie doesn't change, and there is no POST data. It's not really the cookie, though it probably uses the cookie for tracking. The server must keep track of the last page requested with each cookie, so it is not really a referrer, either, but similar. —PC-XT+ 01:30, 7 March 2015 (UTC)


 * Maybe you got this reply years ago but if you want to cite web content which has no direct url then you can use the  parameter of Template:Cite web to briefly describe how to get to the content from a url you have tested gives a stable result. Some parameters in url's like   in http://www.theminipage.com/arch/index.cfm?arid=1&editionDate=2015-02-14%2000%3A00%3A00.0&cid=0C2B4252-1372-55DB-FF682BDA9E3C1A5F are useless for others and may contain information about the user who posted the url. Test what is needed and only give a url like http://www.theminipage.com/arch/index.cfm?arid=1&editionDate=2015-02-14 in a citation. PrimeHunter (talk) 03:23, 6 March 2015 (UTC)
 * What about the external link in the Mini Page article? Should that be there?— Vchimpanzee  •  talk  •  contributions  •  20:03, 6 March 2015 (UTC)
 * http://www.theminipage.com/pub/index.cfm or just http://www.theminipage.com/pub seem better than the current http://www.theminipage.com/pub/index.cfm?CID=0C2B4252-1372-55DB-FF682BDA9E3C1A5F. PrimeHunter (talk) 01:16, 7 March 2015 (UTC)

How do I download certain movies directly?
I became a member of a site that allows downloads of videos. The site supposedly provides downloads of videos in various formats. Up to now I have had no problems. When I click on a video, I am taken to a page that has buttons: "download MP3", download mobile version, etc.

I've been clicking on the MP3 links but the download never starts directly. Instead, the video opens up with a play button (but does not start playing), and then I just right click and choose save video as.

But as I've gone backwards in time to older videos, there are none in MP3 format. Instead, I can choose .MOV or WMV. When I click those buttons, the video pages says enable Quicktime (for the .MOV), or enable [another player I have that can play windows media viewer files]. When I click that I get nowhere.

What I am thinking is IF is can get the dowlnoad buttons to actual START A DOWNLOAD as would seem to be their intended purpose, I can bypass this problem and I was also thinking that the reason its searching for a program to play, rather than just starting the download is related to some setting in my computer (or browser; I use Firefox; when I tried using Safari I couldn't even figure out how to download anything).--108.46.137.89 (talk) 20:30, 5 March 2015 (UTC) Oh, and I'm using a MAC running Mountain Lion (and don't want to upgrade).--108.46.137.89 (talk) 20:32, 5 March 2015 (UTC)

Analysis of Windows 7 Scheduled Tasks
Hi /Computing, Thanks in advance... I like to think I keep my systems running lean. However, it was not until tonight that I thought to take a close look at my scheduled tasks. I plan to look at each of these very closely, and determine if it is necessary to keep or not. Also I may adjust some of the triggers, so that most of my maintenance happens at the same time every week. Here is a screenshot of what I am looking at: https://i.imgur.com/3bf9rqI.png Are any of these familiar to you? Any red flags? Anything I shouldn't mess with? Anything I should mess with? — Preceding unsigned comment added by Fractal618 (talk • contribs) 22:23, 5 March 2015 (UTC)

how to listen to the same sound through two 3.5mm ports on my pc
I have a port on the back of my windows 7 pc and one on the front how can I plug one 3.5mm headphone into the back and one 3.5mm headphone into the front? — Preceding unsigned comment added by 204.42.31.250 (talk) 22:33, 5 March 2015 (UTC)
 * Is the issue that you can only select one output at a time in the software? It might not be possible to select two separate outputs simultaneously, it really depends on the device and drivers. The 1st thing I'd be checking is just go into the "playback devices" settings (you can right click the little speaker icon in your notification bar) and see what settings you have available there. if it's not possible you can just get a Y splitter and connect 2 headphones to the same output.  Vespine (talk) 04:00, 6 March 2015 (UTC)


 * See datasheets of the 3.5mm connector jacks. Former earphone connetors turn the speakers off by opening switches (contacts) of both stereo channels to the speakers. Todays 3.5 jacks close a contact to ground (zero volts, computer bodys potential) when a 3.5 plug is inserted, to sense this to the computer. By using an Y-splitter, you may doubling the load of the output which may cause effects of less sound quality by missbalanced impedance. -- Hans Haase (有问题吗) 08:42, 6 March 2015 (UTC)


 * I think the issue here is that you can't use both ports at the same time? That is quite common with current PC designs. Withour knowing the model of your PC, we cannot get into specifics. You may be able to change this behavior through the control panel. --  Gadget850talk 10:23, 6 March 2015 (UTC)
 * First, it should be clarified that on most modern PCs, there's no problem with using two ports simultaneously. As somewhat mentioned by Hans Haase, On older PCs (like before 2005 or something), the the front audio port may have physically muted the rear ports so it may have been not possible. On modern computers, this doesn't normally happen, the only thing that normally does is your hardware detects when something is plugged in to one of the front ports, and may change the default output to the front port. (Note that most of the time, it doesn't even mute the other output virtually, it's just that the default output changes.)
 * You can easily test this if you have use something like VLC, Media Player Classic - Home Cinema or whatever that lets you select which output to playback to and supports multiple instances. Just plug the headphones or whatever in, start two or more instances of the player and try playing some media file (one or more it doesn't really matter) to each output you want to test (a seperate one per player).
 * The problem comes when you want the same output to both ports. While this is partially related to PC design it's really more OS and to some extent driver design that makes this difficult. I've wanted to do something similar before, in my case it was actually output to both a Bluetooth device and a HDMI output, but in researching this I read a bit about doing it with other outputs too and a lot of it similar. Theoretically if it's the same device (unlike my case), the driver or hardware could present the outputs as a single output and you'd be fine. Unfortunately AFAIK little hardware or drivers support this (well I don't actually know of any, but some may exist).
 * The other options are two simultaneously output to two different devices. Unfortunately Windows doesn't support this what they call broadcast mode itself. So instead you need to get something else to do it, or something similar.
 * If you only want to play audio or watch moves and you aren't set on the media player, you can probably find a free (probably even FLOSS) player which can output to two devices simultaneously. I admit, I never found one, but I didn't look much since it wasn't sufficient for my purposes.
 * If none of that works for you, there are only two other alternatives I'm aware of if you want to stick with Windows (beyond plugging the headphones in to a single plug, or using some physical device which can output to 2 headphones).
 * One is if you have a RealTek, Creative or some other audio device with a "what you hear"/"stereo mix"/"Wave Out Mix" or some other recording device which basically can be used to record the output you hear. Quite a lot of computers do have a RealTek audio devices, and it's possible some other audio devices have such an option. Bear in mind the Windows default drivers probably don't provide the "what you hear" recording device, you may need to go to the Realtek or whatever site to download the manufacturer drivers. Also it may be disabled and hidden, so make sure you show hidden devices in the recording tab of the Sound control panel menu. Once you have the "what you hear" recording device, make sure both the front and back headphones ports are enabled under playback devices. Set one of the audio outputs as default, doesn't matter which. Now make sure the "what you hear" under recording is enablled, and go to properties, there should be a listen tab in Windows 7+ (and I think Vista). Enable listening to the "what you hear" device. Under "playback through this device" option, chose the other audio output, not the default one.  Any program outputting to the default audio output should also effectively simultaenously output to the other audio output. (More correctly, the audio driver is recording the output to the default device and outputting it to the other audio output.) I'm not certain if there could be a slight latency difference in the outputs, if both are headphones I presume it doesn't matter.
 * If you can't get a "what you hear" recording device, there is a program called Virtual Audio Cable which can do something similar. Unfortunately it's not free and is intended for a bunch of other stuff too (which affects the price) . Also because it's working at a slightly higher level and is completely CPU dependent, you may be more likely to have problems like the audio breaking up, or latency issues (but you can set the latency). Anyway, there is a trial which will should help you decide if VAC would work, and whether it's worth the price to you. If you do install it, you can use it similar to the "what you hear". Except in this case, you set "Virtual Audio Cable" to be the default playback device. Then you open up two instances of the Audio Repeater which comes with VAC, and set the wavein to the the VAC and waveout to be the two headphones in seperate instances. You may want to reduce the latency and set priority to be realtime to reduce problems. (One advantage with this option is that you can output to more than two devices. Another is that if you do want matched latency and you're not that worried about a small latency increase, you may be able to achieve that by fooling around with the latency values.)
 * While these options would work, it may simply be easier to get a Y-splitter. It's true the quality may be a bit reduce, but I'm not sure you'll notice, particularly if the headphones are very similar or the same, since computer audio outputs tend to be fairly robust.
 * BTW related to my earlier point if your computer has multiple ports on the front or back, on the vast majority of computers for the past 9 or so years you should be able to use any of these ports for headphones, speaker or whatever, even if they are technically mic ports due to the red colour or whatever. This won't affect the audio quality, from the hardware POV there's very likely no difference besides the colour.
 * P.S. While researching this answer, I came across and  which may be an alternative to Virtual Audio Cable, but I haven't looked that well in to these. I also see xpclient mentioned here  that they did find drivers able to output simultaneously, unfortunately they gave no further information. (It's also possible when they mentioned simultaneous output, they are actually using the "what you hear" recording device.)
 * Nil Einne (talk) 13:54, 9 March 2015 (UTC)