Wikipedia:Reference desk/Archives/Computing/2017 November 19

= November 19 =

mds_stores is a disk hog as is systemstatsd; can I kill them?
iMac11,3; Intel Core i5; 2.8 GHz; 8 GB; OS X 10.11.3

My computer's running a bit sluggish. (I probably should delete some saved movies; I have far too many; according to Activity Monitor I have 6.14 GB of memory used of my 8 GB.) Anyway, when I look in Activity Monitor, the two biggest active disk hogs are the headlined programs (after Firefox, when I'm online). After a bit of googling, my understanding is that mds_stores has something to do with Spotlight, whch I never use. I always run searches through Finder, though I understand they use the same index. Long and short of it: Is there any problem with turning off mds_stores? Actually, a related question is whether I can, or if it will just relaunch? If the answer to the first question is that it would not be a problenm, then how do I do it so it stays off? Basically, same questions about systemstatsd. Do I need that disk hog running? Can I just turn it off through Activity Monitor, or some other way? I guess I have another question. It occurred to me that since Activity Monitor is accessing system information, the reason I always see systemstatsd as high usage mght be because it runs high when Activity Monitor is being used, so it might be a 'refrigerator light issue', if you see what I mean. Thanks--185.77.248.5 (talk) 01:09, 19 November 2017 (UTC)
 * "Saved movies" have nothing to do with "6.14 GB of memory used". The latter is your computer's RAM. The movies are not in RAM unless you have them currently opened in a program, and even if you did, only a small portion of them would be loaded into RAM at any one time. Your movies, along with every other saved file, live on your computer's hard drive(s) or solid state drive(s). Anyway, if mds_stores is an indexing service, it's very likely that it's set to only run when your computer's drives are idle—that is, when nothing else is accessing them. So turning it off is unlikely to make your system faster. I'm afraid I'm not familiar with OS X; if you really want to turn mds_stores off, try a Web search for something along the lines of "os x turn off mds_stores". If that doesn't help, try replacing "mds_stores" with "service". As for systemstatsd, I think you are likely correct. You could always experiment with disabling services temporarily and seeing if things are faster. You're not going to break anything; at worst, you'll have to restart. Also try a Web search for something like "os x make faster". --47.138.163.207 (talk) 09:02, 20 November 2017 (UTC)

Factorials
How do we find factorial of number directly i.e. without writing a program etc.(which will find it anyway) in Visual Basic ?210.56.109.192 (talk) 08:20, 19 November 2017 (UTC)
 * Visual Basic doesn't have a built-in factorial function - this page lists the functions that are available. To calculate a factorial, you will have to write your own function, I'm afraid.  It's not difficult, fortunately. Tevildo (talk) 09:26, 19 November 2017 (UTC)
 * The Factorial n! of an integer n is obtained by multiplying together all the integers up to n. For example if n=5, its factorial $$5! = 5 \times  4  \times  3  \times  2  \times  1 = 120.  $$. A BASIC program can do this in a loop:

 PRINT "Please enter number n"	INPUT N	F=1 FOR J=2 TO N	 F=F*J NEXT J	PRINT "Factorial n!"; =;F  But if by "find directly" you mean obtain n! without doing multiplications, it will be necessary to store a table of values of n! for various n. Such a table is found in the article Factorial. But note that 16-bit integer arithmetic cannot handle larger factorials than n=8. Blooteuth (talk) —Preceding undated comment added 15:09, 19 November 2017 (UTC)
 * Maybe the OP is asking for a closed form solution. I don't think there is anything much simpler than the product version. Stirling's approximation provides an approximate solution, but it requires the computation of an nth power. --Stephan Schulz (talk) 15:22, 19 November 2017 (UTC)


 * The Wolfram language can do this with n! see http://reference.wolfram.com/language/ref/Factorial.html Graeme Bartlett (talk) 00:05, 20 November 2017 (UTC)

OP: And even non-scientific pocket calculators these days ! button! — Preceding unsigned comment added by 27.255.222.174 (talk) 18:11, 22 November 2017 (UTC)
 * If you were using C you could get factorial directly by including math.h and calculating tgamma(n+1) and converting it to an integer. Unfortunately that is not a standard function in visual basic.. Dmcq (talk) 22:24, 25 November 2017 (UTC)
 * p.s. the conversion to integer should use round as the value may be very slightly off. Dmcq (talk) 00:03, 26 November 2017 (UTC)

Python, storing and retrieving data
What options are common for storing data for retrieving them at another session? Json, sqlite3, csv? Anything else? B8-tome (talk) 13:28, 19 November 2017 (UTC)
 * There's also pickle.- gadfium 22:24, 19 November 2017 (UTC)

What is Quick Decompressor?
That is my question. Also is it malware? If so, shall I remove all traces of it from the registry (Windows10) --AboutFace 22 (talk) 17:06, 19 November 2017 (UTC)
 * See here. Ruslik_ Zero 19:57, 19 November 2017 (UTC)

I got an email from my professional organization (actually another company that allegedly works for them) and that email had an attachment file with the extension ".emz" I've never seen anything like this. When I clicked on this attachment line in the email, another page opened with various offers, some paid, one free. The free one was Quick Decompressor. I was not sure if I should get it but simply clicked on it. Without further ado this program got downloaded and installed, by itself. No other clicks were required.

My computer almost immediately developed problems. I could not open my email browser anymore, the folders would freeze, execution became slow. I got scared and uninstalled the sucker. Still for two days the problems remained. I checked the registry and Quick Decompressor is there. Some consolation is that it seems to be a Microsoft program. --AboutFace 22 (talk) 23:07, 19 November 2017 (UTC)
 * Well, as far as I can figure out, Quick Decompressor is not a Microsoft program, but a "free" (as in maximally cheap, not as in freedom) third-party download that is only published via the Microsoft Store. It's reviews are quite abysmal, and at least one review claims it was infected with malware, while many complain about it being hard or impossible to uninstall. A .emz file seems to be a compressed image archive. You can unpack it with WinRAR or 7Zip, according to German Chip Magazine. --Stephan Schulz (talk) 07:57, 20 November 2017 (UTC)
 * Translation: it's malware. Try running Spybot Search & Destroy and see if that does the trick. Deleting Registry entries will likely not do much. In the future, don't click on attachments you weren't expecting to receive. And are you running an antivirus program on your system? If not, Windows Defender is free from Microsoft. --47.138.163.207 (talk) 08:30, 20 November 2017 (UTC) --47.138.163.207 (talk) 08:30, 20 November 2017 (UTC)

Thank you both for additional information. We live in a dangerous world, for sure. I've had Spybot Search and Destroy free edition for years but recently paid for professional version. It is less expensive than to donate money to them when they asked. I will see what can be done additionally. That attachment with .emz file did not seem to belong there since the message which I investigate now through our DOPL is printed in the email's body. Thank you. --AboutFace 22 (talk) 22:24, 21 November 2017 (UTC)

windows 10 vs ubuntu
Hi, I've been having constant problems with windows 10 restarting (bsod), and tried fixing from the internet, with no end in sight. Is microsoft aware of the problem? Are they going to create a patch of some sort to stop this garbage? Otherwise, I am looking to install ubuntu. I have downloaded ubuntu 17.10 onto my windows 10, hp laptop. Do i just click on this to intall? Will it take care of everything, and leave my win 10 filesystem intact? Regards, IBE (talk) 22:34, 19 November 2017 (UTC)


 * I do have Windows 10 on HP Pavilion. It works fine. I have Ubuntu 16.04 LST on my HP laptop and it works very well, no complaints. It is a more convenient OS. I used to have a Dell machine where I installed Ubuntu parallel to Windows 7 and both worked well. You have to use .iso disk with Ubuntu on it. Just put it in the bay. When you turn the computer on, the BIOS will detect the second OS and will ask you if you want to overlay Ubuntu over Windows 10 or have both OS together. Choose the second option. With BSOD, I don't know how it will work. Perhaps you will have to reinstall Windows 10 from Microsoft. $120 home edition. Read this about BSOD --AboutFace 22 (talk) 23:18, 19 November 2017 (UTC)


 * I don't know what causes your bsod. If it's a hardware problem, a new OS won't fix it. You have to use the .iso to create a bootable dvd or usb drive, then boot it, which isn't necessarily trivial as not all hardware manufacturers keep to the standards. It should take care of most things, but don't assume your Win10 filesystem remains intact. At the very least, it will have to be shrunk, so make sure you have backups. I recommend you find help on a dedicated Ubuntu forum instead of the Wikipedia refdesk. And don't assume that Ubuntu is a drop-in replacement for Windows. PiusImpavidus (talk) 09:11, 20 November 2017 (UTC)
 * Technically it may be possible to use Wubi (software to install from within Windows without requiring booting from a DVD or USB stick [//help.ubuntu.com/community/Wubi] [//www.lifewire.com/wubi-linux-installation-program-2201175] although it's no longer recommended or supported by the developers of Ubuntu . Of course things can go wrong whatever you do so you should make sure your backup is up to date before doing anything major like this. (I'm assuming you already have a backup of any data that matters because if you don't you're probably going to lose it at some stage no matter what OS you're running or whether it's on an SSD or hard disk.) Nil Einne (talk) 09:53, 21 November 2017 (UTC)


 * I'm going to answer your question in reverse order.
 * "[will it] leave my win 10 filesystem intact?" -- Don't bet on it! Make a backup of everything you care about before installing a new OS. Theoretically the windows partition can be resized to make room for the Linux partition. That's great, but don't depend on it. Assume that your windows partition will be deleted and plan accordingly. (Then if it does work, it'll be a pleasant surprise.)
 * "Will it take care of everything?" -- Dunno. If your windows system is screwed up because of a bad driver, or a virus, then yeah, probably. If your windows system is screwed up because of a hardware fault, overheating, or overclocking, then no, probably not.
 * "Do I just click on this to install?" -- No. I'm not sure what you downloaded, but it was probably an image of a bootable disk. You'll need to put that on a disk or USB stick in a way that makes it bootable. here is a how-to guide.
 * "Is microsoft aware of the problem? " -- This is a problem with your computer. It is not a general Windows 10 issue. So are they aware of the problem with your personal computer? Uh, they might be, actually. There's a lot of data collection in Windows 10. But don't expect them to fix it for you.
 * ApLundell (talk) 19:22, 20 November 2017 (UTC)


 * I just want to echo what PiusImpavidus said. What makes you think that this is a software problem?  If it's a hardware problem, changing the OS won't fix it.  You need to diagnose the problem (or get someone else to do it).  Alternatively, you can buy yourself a new computer. A Quest For Knowledge (talk) 19:49, 20 November 2017 (UTC)


 * I'm calling it software, because I haven't changed any hardware, and it worked fine when I got the computer. So it looks like some update has made things start to crash. This could be e.g. a driver, but then these interface with windows, and windows is the thing that decides to go bsod on me, instead of restarting the driver/ warning me that it needs replacing. Windows gives very little feedback when going bsod, mostly just "IRQL_NOT_LESS_OR_EQUAL". At other times, it said it was "dxgmms2.sys" which is some Nvidia thing. I tried disabling the nvidia card, but I'm not sure if it really did anything, and I've still been getting bsod. So I don't know why this would be hardware. IBE (talk) 21:22, 20 November 2017 (UTC)
 * Hardware breaks all the time. And you didn't mention anything about contacting the manufacturer about the problem, which makes me think the computer is at least 1 year old. (Note that it's that likely they will do anything but they may at least let you RMA the computer.) And even without hardware breaking, overheating problems can cause a lot of weird errors and stuff is more likely to overheat once fans start to clog etc. A lot of what you are describing sounds a lot like it could be a hardware problem. I'm not saying it's definitely a hardware problem since it could also be a software problem but from all you've said, there's no reason to favour software problem over hardware problem. If you were regularly running Ubuntu or some other OS (whether installed or on a live DVD/USB key) and not getting the problem then you have reason to favour software problem, but not from what you've said so far.  Also why do you think dxgmms2.sys is "is some Nvidia thing"? As far as I can tell, it's a standard part of Windows in particular part of the DirectX Graphics MMS and do would likely be used by any graphics hardware whether AMD [//community.amd.com/thread/205736] or Intel. It's possible if it is a software problem it's somehow connected to Nvidia, e.g. this thread [//www.reddit.com/r/nvidia/comments/4h7kgp/directx_12_dxgmms2sys_dxgmms1sys_issues_with/] seems to relate to a possible problem with Nvidia drivers, or alternatively it could relate to a fault with the Nvidia hardware but it's also possible it has nothing to do with Nvidia per se and is related to some other problem.  Nil Einne (talk) 10:00, 21 November 2017 (UTC)