Wikipedia:Reference desk/Archives/Computing/2012 August 16

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August 16[edit]

MediaWiki: get URL params[edit]

Question moved to Village Pump. 178.216.128.99 (talk) 06:53, 17 August 2012 (UTC)[reply]

SATA III hard drive in a SATA II interface?[edit]

Will a SATA III (three) hard drive work in a SATA II (two) interface? JIP | Talk 18:30, 16 August 2012 (UTC)[reply]

As our Serial ATA mentions, there isn't such thing as SATA III. It doesn't really mention but there isn't really such thing as SATA II [1] either. The term SATA II is usually used to refer to the 3 Gbit/s interface speed and SATA III a 6 Gbit/s interface speed but the rev 2.0 of SATA included a number of enhancements beyond the speed increase, similarly rev 3.0 of SATA; however many hard disks may include some features supported by the new revision (particularly the increased interface speed) but not all so it's difficult to answer without knowing precisely what you're talking about. (AFAIK, SATA is supposed to always be backwards and fordwards compatible between revisions although as our article hints at, in practice problems sometimes occur.) Nil Einne (talk) 18:52, 16 August 2012 (UTC)[reply]
I was mainly interested in buying this hard drive. It says "SATA III" on the page, however I'm fairly sure my computer's motherboard only has a SATA II (SATA rev 2.0?) interface. JIP | Talk 19:26, 16 August 2012 (UTC)[reply]
According to [2], that drive has 6 Gbit/s transfer speed which is probably what that vendor means by 'SATA III'. According [3], the drive has a jumper to limit it to OPT1/1.5 Gbit/s which suggests 2 things. 1) At the time designing the drive, WD hadn't encountered enough problems with the drive interface controller (or ones like it) and 3 Gbit/s SATA controllers to make a 3 Gbit/s jumper something worth implementing. 2) Worst case scenario, you should be able to enable the jumper and limit the drive to 1.5 Gbit/s and it should work. From [4], there should be no real disadvantage in raw speed since at the beginning of the drive, it's still about 15 MB/s away from saturing a 1.5 Gbit/s link (presuming you aren't doing something like using a port multiplier). Note that I don't know if the OPT1 jumper stops other things like NCQ (which I presume the drive has). Also I'd avoid reading too much into the TechARP review beyond a rough idea of the raw speed since they seem to have come to the conclusion the EARX new drive is slower then the older EARS drive based on what I think is a sample size one each. (I.E. All their actually saying is our single EARX is slower then one single EARS.) P.S. However remember no one can guarantee any specific model will work with your system, except perhaps your vendor. I know of someone who encountered a random compatibility problem with a WD? drive and some motherboard several years back. I never found out what the problem was but it sounded like something fairly well known to those who seel the motherboard but also something rather unusual. Nil Einne (talk) 21:53, 16 August 2012 (UTC)[reply]
From everything I've heard, SATA revisions are supposed to be fully backwards compatible. You'll just be limited to the features and speeds supported by the oldest hardware in the chain. Horselover Frost (talk · edits) 22:07, 16 August 2012 (UTC)[reply]

Plotting ping results on a graph[edit]

Resolved

I would like to plot some ping results on a graph. The data comes from the standard Windows ping tool and is in the format;

~ 16/08/2012 18:15:21.82
Reply from 173.194.78.94: bytes=32 time=53ms TTL=47

~ 16/08/2012 18:16:22.26
Reply from 173.194.78.94: bytes=32 time=19ms TTL=47

~ 16/08/2012 18:17:22.94
Reply from 173.194.78.94: bytes=32 time=30ms TTL=47

etc

The date and time have been added by me, and I can change it to any format if that would make plotting the results easier. The data I want to plot on the graph is the "time=(x)ms" part of each ping request against the date and time of the request. If possible I would like to do this in Microsoft Excel 97. The log file containing the ping results is over one thousand lines long, so I cannot do it manually. I have very little experience in plotting data on graphs, so I need lots of help and advice. Thank you for your time 92.233.64.26 (talk) 19:43, 16 August 2012 (UTC)[reply]

Well it will be easier if you have everything on one line, date time and response time, then you can load the data to excel and allow space separation to get it into fields. There are other products around lie Multi Router Traffic Grapher that can do this on a much bigger scale automatically. This awk command will do the conversion to combine on one line and strip back the time:
 awk '/^~/{a=$0};/Reply/{sub(".*time=","");sub("ms.*$","");print a,$0}'

Graeme Bartlett (talk) 22:02, 16 August 2012 (UTC)[reply]

Thanks for the reply. I am not familiar with "awk", is it a linux program? The windows version I downloaded from the gnu sourceforge page seemed to fail with the command above, perhaps because the command prompt was interpreting the special characters differently? 92.233.64.26 (talk) 00:14, 17 August 2012 (UTC)[reply]
In Windows, you should be able to use something like the script below. If you edit the lines above the first blank line, and save it with a .cmd extension, when you run it it gives you a CSV file which you can open in excel
set FAILURE=Failure
REM the above is what will be written to the third column if there is no reply	
set outfile=ping.csv
set host=www.bbc.co.uk
set attempts=10
set delaybetween=1000
rem the above is in milliseconds

echo wscript.sleep(%delaybetween%)>sleep.vbs
echo Attempt,Date,Time,Replytime > %outfile%
set count=1

:loop
ping -n 1 %host% | find /i  "reply from" > %outfile%.tmp
if errorlevel 1 goto FAILURE
for /f "tokens=7 delims== " %%T in (%outfile%.tmp) do echo %COUNT%,%DATE%,%TIME%,%%T >> %outfile%

:BACKFROMFAIL
cscript /nologo sleep.vbs
set /a count=%count%+1
if %count% LEQ %attempts% goto loop 
goto theend

:FAILURE
echo %COUNT%,%DATE%,%TIME%,%FAILURE%
goto BACKFROMFAIL

:theend
if exist sleep.vbs del sleep.vbs
if exist %outfile%.tmp del %outfile%.tmp
Hope this helps, davidprior t/c 07:43, 17 August 2012 (UTC)[reply]
Well the awk that I used was under windows but done in the cygwin environment. I actually did test it on your sample data. The awk commands were quite standard, so the characters should not have affected anything, and should work on every version. If you use nawk you may get a more helpful error message. Another alternative would be an excel formula that selects every third line, and uses functions to edit the strings retrieved. I am a bit vague about the exact functions for excel. Graeme Bartlett (talk) 09:18, 17 August 2012 (UTC)[reply]

Thanks for the help everyone! 92.233.64.26 (talk) 11:16, 17 August 2012 (UTC)[reply]

Windows task bar disappearing[edit]

For the last week or two, the task bar in my Windows 7 system has been disappearing a few times per day. It is NOT hidden. I have it locked. If I log off and log back on (or restart), it comes back, for a while.

I have Norton Security and I've run Microsoft Safety Scanner and MalwareBytes, and they didn't find any malware.

Is there a solution for this problem? Bubba73 You talkin' to me? 20:18, 16 August 2012 (UTC)[reply]

I think we'd need a lot more info. For obvious stuff, you made sure it's not on auto-hide (doesn't seem like that's it, but check). Are you running anything peculiar in the background? It's possible that explorer is crashing. Are there any other things that trigger this, or other strange behavior? You might see if this happens in safe mode. Also try looking at msconfig and see what it shows you for both non-ms services and startup items. You might see if something new's been introduced there. Shadowjams (talk) 04:32, 17 August 2012 (UTC)[reply]
Yes, I made sure it is not auto hide. It just seems to disappear by itself and sometimes it comes back by itself. For instance, when I got up about an hour ago, it was gone. It stayed off while I used it for about a half hour, then I went to eat. I came back a few minutes ago and now it is back, and it came back by itself (I didn't log off or reboot). Bubba73 You talkin' to me? 16:29, 18 August 2012 (UTC)[reply]
And it has just been sitting there for a while, and the task bar has disappeared again. Bubba73 You talkin' to me? 21:13, 18 August 2012 (UTC)[reply]

I uninstalled a third-party screensaver that I installed about the time the problem started, and that seems to have fixed it. Bubba73 You talkin' to me? 04:16, 20 August 2012 (UTC)[reply]

Resolved

loop 128 PNG files at 15 fps onto a 10 minute youtube video[edit]

This is for a scientific experiment, and the best way to do it is to project a high contrast series of stripes to my fruit flies to an iPhoone sitting on top of a transparent experimental arena; I created a bunch of stripes in different positions in MATLAB-- the trouble is that while I can find flv editors that will loop a single sequence of images ONCE, I cannot find an application that will write a single sequence over and over again into a single video file until a certain amount of frames has been reached. I'm basically using my iPhone so I would like to play a looping series of stripes off of Youtube (which I will upload to). I cannot use any browser-based methods (e.g. animated GIF) as there will light leakage from other components (I need blue light coming from the iPhone only, or black, else it will ruin the selective dual color imaging setup, as I am observing fruit fly behavior through a red filter and need the stripes of the phone to be invisible). The nice thing about Youtube is that the "controls" disappear after a few seconds. 137.54.29.134 (talk) 21:45, 16 August 2012 (UTC)[reply]

VLC media player can play a video in a loop in full screen mode on a PC. ImageMagick or GraphicsMagick can make a video from a sequence of frames, and can likely make a frame of stripes for you too. They are command line driven so can be quite flexible once you know what you are doing. You can put your modern broswer into full screen mode in modern versions so you onl.y see page content, so you may want to explore that option. Graeme Bartlett (talk) 22:24, 16 August 2012 (UTC)[reply]
Yeah, it is hard to believe your best option relies on an iPhone and YouTube… is the point of the experiment the light and flies or using an iPhone?
If you were to use an ordinary monitor you could tape over any extra lights (you'd presumably have to do this for other things in the room anyways). FFmpeg doesn't seem to quite support looping a sequence on its own yet, which is unfortunate. 128 divided by 15 is hard to divide 10 minutes by as well… can we assume looping the sequence 70 or 71 times would suffice (or 100, a nice round number)? ¦ Reisio (talk) 23:29, 16 August 2012 (UTC)[reply]
An iPhone is ideal because it matches the size of our 3"x4" arena. It's very hard to mount a monitor right on top or below a level arena, which is what must occur in order to avoid the effects of geotaxis (gravity-driven congregation in the "upper" portion of a non-level arena). Any further and the contrast is diminished. Right now, I know how to make a video from a sequence of frames, but what I need is for the loop to occur in the file itself (the iPhone Youtube app doesn't have a loop function). Of course, if there's an iPhone app that can turn its dashboard off and repeat videos, that would be awesome. 137.54.29.134 (talk) 23:48, 16 August 2012 (UTC)[reply]
According to http://google.com/search?q=iphone%20app%20video%20repeat there are such apps, including one named "Loop Video". ¦ Reisio (talk) 00:05, 17 August 2012 (UTC)[reply]
There probably is. Otherwise, if you can upload the images somewhere I can assemble the video as originally requested (except looped 70, 71, 100, etc. times and not 10 minutes exactly). The shell scripting I would use is so ugly I will not share it publicly. :p ¦ Reisio (talk) 23:56, 16 August 2012 (UTC)[reply]
The files are here here. 137.54.1.117 (talk) 20:38, 17 August 2012 (UTC)[reply]
To avoid network issues you should probably use the iPhone's own player to play a local video, though. Does that have controls that show up by default? If so how long do they take to disappear? Which model iPhone? ¦ Reisio (talk) 23:59, 16 August 2012 (UTC)[reply]
I found an app [5] which will play animated gifs in full screen.  Card Zero  (talk) 08:10, 17 August 2012 (UTC)[reply]
The reviews say it doesn't work-- I'm hesitant to try because of the price tag.
Would it work to take the sort of video projector you use to give a lab presentation, and focus it onto a translucent piece of paper under the arena? I'd think you could get a perfect fit that way, and more luminosity than the iPhone can provide, with more flexibility. Wnt (talk) 19:00, 21 August 2012 (UTC)[reply]