Wikipedia:Reference desk/Archives/Computing/2010 August 28

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August 28

Origin of level numbers in Cobol

Hi,
How where the numbers 66, 77 and 88, used for Cobol level numbers, chosen? Apokrif (talk) 00:26, 28 August 2010 (UTC)

This is definitely an interesting question. I did some research, but unfortunately language specifications and such usually don't retain this sort of information. The history of the choice might still be held by a programmer with a beard grayer than mine, but the reason seems obvious. Since these numbers have special meaning, it makes sense to use number combinations that are easily noticed in the middle of the code. It's an early version of Syntax highlighting. Zigorney (talk) 17:24, 28 August 2010 (UTC)

Sony Bravia TV time display

A small black box with the time in it is appearing on my Bravia when I use the PS3 on HDMI and the PS2 on component cables. I've looked through all the menus but I can't find where to deactivate this. Does any one with a Bravia know how to do this? Thanks. ArtistScientist (talk) 02:47, 28 August 2010 (UTC)

"Internet not connected" messages when internet works fine...

So, I'm obviously on the internet now. I can use AIM, browse the web (i.e. Google, Wikipedia, facebook, pretty much all websites). But for some reason, there are certain things that just WILL NOT connect, and I get "check your internet connection" and "internet is not connected" messages from them. I can't get on the iTunes store, use my iWin Games Manager for anything other than games I've actually bought previously, MSN Messenger won't connect, and when I try to download the daily free game from GameHouse, it won't play either because it thinks I'm not connected to the internet. To clarify, other than these things, the internet works FINE! It's even fast! This stuff is getting really irritating, so if someone could tell me how to fix it, that would be great... —Preceding unsigned comment added by 129.1.198.239 (talk) 04:44, 28 August 2010 (UTC)

Which Web browser do you use (Internet Explorer, Firefox, Google Chrome)? PleaseStand ^(talk) 04:58, 28 August 2010 (UTC)

Firefox. Always. Not sure what version, but I'm pretty sure it's whatever the latest happens to be. —Preceding unsigned comment added by 129.1.198.239 (talk) 05:03, 28 August 2010 (UTC)

From within Firefox go into the Tools Menu then Options, Advanced, Network and click Settings (Configure how Firefox connects to the Internet). Most likely you want this set on "No proxy", but auto-detect should usually work. Hope this helps!  ZX81  ^talk 05:37, 28 August 2010 (UTC)

No, what was asked for was to get the other programs working, not Firefox. Some programs (malware included) mess with the Internet Explorer proxy settings, which may be used by other software. What you should try doing is turning off proxy settings for Internet Explorer by following Microsoft's instructions, except that you need to uncheck "Use a proxy server" rather than checking it. PleaseStand ^(talk) 05:52, 28 August 2010 (UTC)

As PleaseStand said, it might be caused by malware, but another possibility would be a transparent proxy or a firewall setting. According to http://en.utrace.de/?query=129.1.198.239, you are at Bowling Green State University, so you might want to ask the staff there. -- 78.43.71.155 (talk) 10:13, 28 August 2010 (UTC)

(... and they might tell you that the facility is not provided for downloading music or games.) It sounds like a deliberate bock by the network administrators. Dbfirs 02:09, 29 August 2010 (UTC)

DHCP irritations

[Preamble: I made a confused question about this back on 10 August, then had to use a different place; now am back with a clearer head.]

There's an ethernet cable in my office. If it's plugged directly into my computer, then when I come in and first turn on the computer, start up a browser and attempt to go anywhere, I'm greeted by a page for DHCP that asks me for my ID and password -- and after I've typed both in correctly I stay connected all day, or at least until the computer falls asleep and is reawoken. By contrast, if the ethernet cable is instead plugged into a wireless hub (router?), and the hub in turn connected to my computer, then after just a few minutes regular browsing becomes impossible: I'm instead served with the log-in page and must again type in my ID and password, which gives me a few minutes, until I'm instead served with (etc etc). Of course the whole point of the wireless hub is wireless and/or a second computer; but for diagnostic purposes I only have one computer (and no printer, etc) connected, and by wire. I don't see why my choice among the output jacks should matter, but I've tried two: each has the same irritation.

What setting of my hub might be relevant? Or if I were to buy a replacement hub, then which "feature" should I look for? -- Hoary (talk) 06:47, 28 August 2010 (UTC)

I think I remember this question. If it's what I remember, this is a lot of new information, and highlights perhaps some misunderstandings. It's a bit of a non-sequitur to say that you're "greeted by a page for DHCP". When you plug in to your computer, what's likely happening is your computer asks for an IP address, a DHCP server responds with one, and then web server sends you to a login page. When you authorize, it somehow authorizes you.

The most interesting new issue is the "hub", which you acknowledge is probably not a hub. That's probably the case, as it's hard to inadvertently buy one these days. What kind of device are you plugging this into? That is probably an important point. I'm fairly confident this issue has almost nothing to do with DHCP. Shadowjams (talk) 07:25, 28 August 2010 (UTC)

Thank you for your patience. I've located the box that this device came in. It advertises its features -- primarily a wireless throughput (measured in some way or other) of 150Mbps -- and I have to look long and hard before I see what it is: a wireless LAN broadband router.

(I transliterate/translate from the Japanese. It looks a lot less like the photo illustrating router than it does the photo illustrating network switch, or indeed ethernet hub. In the store, there are lots of cardboard boxes that all boast stunningly high speeds -- qualified by small print -- and lots of variants on "IEEE802.11". My ignorant choice among these cost me very roughly €50.)

It's got six sockets on the back: power, "WAN", and "LAN"×4. It also has on/off DIPs for multi AP function(s) and router function(s). (The manual -- 130 pages plus, most of which is specific to OSes that I don't have -- tells me that multi AP functions have something to do with security; I've no idea why anyone would want to turn off the router functions of a router. You've guessed it, I haven't a clue what any of this means.) -- Hoary (talk) 08:14, 28 August 2010 (UTC)

Undoubtedly this intermediate device is involved in the issue. The fact it has a WAN and a separate LAN port designation strong suggests it's doing some management of its own. It's probably some relation to this that's the root of your problem. Is there a model number on the device? Shadowjams (talk) 08:36, 28 August 2010 (UTC)

It's a Corega CG-WLRGNX. You can see it (all in Japanese!) here. (Corega also has a website in a language approximating English, but I don't see anything looking like this "CG-WLRGNX" there.) -- Hoary (talk) 08:57, 28 August 2010 (UTC)

Into which port of your CG-WLRGNX are you plugging which cable? As you said, it has one WAN and four LAN ports (let's call them LAN1 to LAN4), and plugging it in in different ways will yield different results. Please tell us where the ethernet cable from your office goes, and where you tried to connect the client computer(s). -- 78.43.71.155 (talk) 10:06, 28 August 2010 (UTC)

The ethernet cable from my office goes into "WAN" and the cable going to the client computer was until today plugged into one of the four "LAN" connectors but from today is plugged into a different one of the four. Power cable, ethernet from my employer, ethernet from my computer: these three are all that are plugged in. -- Hoary (talk) 11:15, 28 August 2010 (UTC)

What are you using the router for? If you're using it only as an extender or to get wirelesss access, consider disabling the DHCP server on it, and plugging the office cable into a LAN port too. That should turn your router into a switch/wireless access point and allow it to directly access the DHCP server on your company LAN Unilynx (talk) 13:24, 28 August 2010 (UTC)

That is basically the idea I had in mind when I asked Hoary. Some important information regarding this approach:

1. DO NOT, under any circumstances, plug the office ethernet cable into a LAN port while the DHCP server on your CG-WLRGNX is still active! This will cause trouble in the entire network, and you might end up with the wrath of one or more severely annoyed network administrators.
2. You will probably lose the ability to access the config interface of your CG-WLRGNX if you disable DHCP and plug the office ethernet cable into a LAN port. You could avoid this by first asking one of your network administrators for a static IP address and assigning that to your CG-WLRGNX (again, do not do this with the office ethernet cable already plugged in - all that should be plugged in is the computer you're using to configure the CG-WLRGNX) before turning DHCP off.

-- 78.43.71.155 (talk) 20:19, 28 August 2010 (UTC)

Thank you for your efforts. First, here are the two purposes. Simply, I often use a laptop on a table. I could connect it by ethernet but that's one more cable to trip over and one more irritation when I want to move the laptop, eg to rotate it by 180° to show the screen to somebody else. Further, for a few hours most weeks a second person simultaneously uses a second laptop in the same office. Rather than passing the one cable to and forth, or having more cable forestry, it would be convenient if we were both connected without cable. Right now I'm connected (10 minutes at a time or so) via a cable to this router thing because I figure that if I can't even get this modest function working properly I have no chance of getting wireless to work right. ¶ The device comes with a 138pp manual, which lacks an index. Most of it is made up of screenshots of how to do things in this or that OS that I don't have. There's no mention of "DHCP" in the contents list. I can download a 21MB PDF of detailed instructions; there's no mention of "DHCP" in that, either. The situation (or its mismatch with my ignorance) is obviously ridiculous so I'd better go ask the techie people (who are always polite, but tend to be unhelpful when you're not using the exact same products that most people are using). Oh well. -- Hoary (talk) 10:47, 30 August 2010 (UTC)

Or you might post the link to your 21MB PDF... who knows, there might be a helpful Wikipedian around that can help you figure out how to correctly set up your router, once the manual is available. -- 78.43.71.155 (talk) 12:10, 30 August 2010 (UTC)

Supplemental: I followed your previous link using translate.google.com and got this http://corega.jp/prod/wlrgnxw/pdf/wlrgnx_detail_d.pdf - which happens to be roughly 21MB in size. is this the file you were referring to? I don't speak Japanese, so I can't tell what it says, but for example Section 4.9.1 does contain something about DHCP - the letters are in there, in rōmaji. It seems that whoever created the PDF made it non-searchable (at least for latin characters), that's what might have lead you to assume it doesn't contain anything about DHCP. -- 78.43.71.155 (talk) 12:21, 30 August 2010 (UTC)

Second supplemental: Chapter 4.5.2 seems to display a DHCP configuration screen. Does the first option, perchance, say "On/Off" in Japanese? -- 78.43.71.155 (talk) 12:27, 30 August 2010 (UTC)

Well well, you're right. Well done! I'm back at home now so can't try it. Tomorrow, tomorrow. In the meantime, this calls for a celebratory bottle of Chimay. -- Hoary (talk) 13:49, 30 August 2010 (UTC)

Dōmo arigatō. *bows, hands at the sides* -- 78.43.71.155 (talk) 16:22, 30 August 2010 (UTC)

Vista copy paste problem

Hello there, I am having trouble in performing "copy paste" thing in my vista OS. I can't copy or paste any single file within my OS. Even I can't drag or drop any file or folder. All started suddenly. Is there any possible way to fix it? Any suggestion would be appreciated. Thank you--182.160.98.36 (talk) 14:04, 28 August 2010 (UTC)

I used to have Vista and found it's copy system awful, although the fact that you can't copy anything at all suggests a bigger problem. Restart the computer and run a virus check in case your computer is infected, as this problem sounds like something a virus might cause. You could also try using TeraCopy or FastCopy as alternatives to the Windows copy system. 82.44.54.25 (talk) 14:10, 28 August 2010 (UTC)

I've found Vista's copy system works fine, though I tend to use drag and drop rather than copy and paste. The paste option is not available if the focus is in the wrong place. I agree that if neither copy nor paste is working then there is a serious problem. You could try copying from command line, but this just uses the same subroutines as copy-paste and drag-drop, so if these have been compromised by a virus then it will not work. Dbfirs 02:03, 29 August 2010 (UTC)

I have a laptop that sometimes I can't drag icons to copy and paste, even emails in outlook won't drag to other folders, but it doesn't seem to have any other issues, like with typing or anything. I eventually figured out it is somehow related to a keyboard issue, I'm not sure what happens or why but pressing alt, ctrl and esc NOT at the same time, just giving them a flick one by one, fixes this in my case. Vespine (talk) 01:32, 30 August 2010 (UTC)

Excel Graph

Hi. I'm having a (most likely, very basic) problem with graphing some data in Excel and wondered if someone could help. So I have the numbers 1, 2, ..., 20 in one column. I then generate the next column (which lists my x values) by multiplying all of these by 0.2, giving me 0.0, 0.2, 0.4, ..., 4.0. In the next three columns I have some data determined solely by the x appropriate x value being plugged into one of three equations (for those interested, I'm actually finding numerical solutions to a differential equation). I then want to plot the final three columns against my x values but every time I try to do this, without fail, the scale for the horizontal axis runs from 0 to 21 and I cannot fathom how to change it to run from 0 to 4. Any ideas? I'm running Excel 2004 for Mac if that helps. Thanks asyndeton talk 14:35, 28 August 2010 (UTC)

Have you tried graphing it as a scatter plot? --Phil Holmes (talk) 15:34, 28 August 2010 (UTC)

No need. If it is the same as my Excel 2000, then just click on the series tab at step 2 in the "Wizard" and choose your second column for the "category (X) axis labels". Dbfirs 01:54, 29 August 2010 (UTC)

No. All the excel options plot values against value index except for scatter which is the only one to plot values against value. In scatter standardly the lefmost column defines all the x coordinates and all the other 'N' columns define the matching y-coordinates of 'N' lines. -- SGBailey (talk) 07:19, 29 August 2010 (UTC)

Well it works in Excel 2000. I tested it before I posted. Are you referring just to the defaults for the graph-type options? You don't have to accept these! They are configurable at the next step. Dbfirs 07:55, 29 August 2010 (UTC)

Using the category X axis lables can work if the X axis data happens to be equi-spaced (eg 0.1, 0.2, 0.3, 0.4, 0.5) but if it is something else (eg 0.1, 0.2, 0.4, 0.8, 1.6) then although the names match, the x-separation can only be got right using scatter. -- SGBailey (talk) 22:45, 29 August 2010 (UTC)

Ah, yes, I was assuming equally spaced x-values. I suppose one could engineer this, but I agree that my method is not a solution in general. Dbfirs 09:23, 30 August 2010 (UTC)

You need to exclude the first column from your data, yes? You should be able to do this by looking at the chart data sources. Alternatively, if you double click on the axis you are having trouble with, there is a tab for "scale", which lets you override the default values. --Mr.98 (talk) 15:22, 29 August 2010 (UTC)

That's what I thought, but see SGBailey's reply above. I wonder why Microsoft make life difficult? Dbfirs 09:23, 30 August 2010 (UTC)

Screen

My computer screen is currently at 60 Hertz. It has the option to go to 75 Hertz. What's the difference? Might setting it higher make looking at the screen less headache inducing? 82.44.54.25 (talk) 20:57, 28 August 2010 (UTC)

If you have a CRT monitor, I'd set it as high as the monitor supports to reduce flicker. See Refresh rate Unilynx (talk) 21:11, 28 August 2010 (UTC)

It's not a CRT monitor, I think it's an LCD or something. It's flat 82.44.54.25 (talk) 22:24, 28 August 2010 (UTC)

In CRTs the pixels decay in brightness until they're refreshed, so the refresh rate is the flicker rate. In LCDs they don't decay, so the refresh rate only affects how quickly the image shown on the screen can change. If an LCD is visibly flickering, it probably means the backlight is dying and changing the refresh rate won't help. If your display isn't visibly flickering but you're getting headaches looking at it, you might want to consult a doctor. -- BenRG (talk) 02:04, 29 August 2010 (UTC)

Firewalled download

My connection to the internet is through a firewall. Whenever I try to download some big files ~50 MB, I get an error stating that the response to the HTTP GET request is above the limit. My guess is that the firewall's checking the file size from the response to the get and then disallowing the download. If that's the case, is it possible to circumvent the check ? 218.248.80.51 (talk) 22:32, 28 August 2010 (UTC)

The trouble is that what you want to stop is behaviour from the remote server. I can think of two solutions, but there may be more: 1) run your own proxy somewhere that strips the Content-Length header. This will be heavy on bandwidth and clunky. 2) Make use of HTTP's Range header to ask the server for the file in pieces. I don't know of any download system that allows for this, but it would be quite easy to knock one up in your favourite scripting language if you're a programmer. (Wget does support Range, but apparently only for continuing a previously-aborted download, which isn't much help if you can't even get started.) Marnanel (talk) 15:28, 29 August 2010 (UTC)

Splitcam open source equivalent

Hi, I use Splitcam to play avis as a webcam. Do you know any open source apps doing this? 83.31.86.106 (talk) 23:47, 28 August 2010 (UTC)

AviSynth, a free and open-source tool, can construct connections between almost any kind of input video source and almost any kind of video output source. Its "user-interface" is far from user-friendly. There is extensive documentation, but you will basically need to write a short script to open the AVI file and deliver video output to your webserver. What exactly do you mean when you say "play avis as a webcam"? Clarifying this will help narrow down your options. Nimur (talk) 20:03, 30 August 2010 (UTC)