Wikipedia:Reference desk/Computing

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September 8[edit]

GeoFs and intel core i7[edit]

Why is this game so laggy with an core i7 and it is very fast with an core i5 --Thegooduser Life Begins With a Smile :) 🍁 22:10, 8 September 2019 (UTC)

Which i7 and which i5? Did all other components of the computer stay the same? I am pretty sure that human life begins with a crying baby, and if the baby does not cry it will get some help. Poveglia (talk) 00:54, 9 September 2019 (UTC)
The oldest i7 vs the latest i5 is not a fair battle https://cpu.userbenchmark.com/Compare/Intel-Core-i7-920-vs-Intel-Core-i5-9600KF/1981vsm772658 Poveglia (talk) 00:59, 9 September 2019 (UTC)
I am talking about core i7 8th gen and a i5 from 2013--Thegooduser Life Begins With a Smile :) 🍁 01:08, 9 September 2019 (UTC)
How much RAM does each have ? SinisterLefty (talk) 01:45, 9 September 2019 (UTC)
SinisterLefty 12GB --Thegooduser Life Begins With a Smile :) 🍁 01:57, 9 September 2019 (UTC)
Same graphics cards ? Same Ethernet speeds ? Same hard drive speeds ? Same O/S on each ? Both 64 bit versions ? If Windows, I suggest running the "Windows Experience Index" calculator, which may give clues as to the weak spot. SinisterLefty (talk) 02:23, 9 September 2019 (UTC)
What do benchmarks show? Bubba73 You talkin' to me? 03:07, 9 September 2019 (UTC)

September 9[edit]

Google Chrome won't let me click on tabs[edit]

I can click on other things, and I can CTRL TAB to page thru the tabs. Is this a bug or some setting that somehow got screwed up ? SinisterLefty (talk) 02:30, 9 September 2019 (UTC)

If you close Chrome, and then restart it, does it still have the same problem? Poveglia (talk) 02:52, 9 September 2019 (UTC)
The problem is intermittent. The next time it occurs, I will try that. SinisterLefty (talk) 03:28, 9 September 2019 (UTC)

September 11[edit]

Creating digital pictures and wallpaper[edit]

How are 3d wallpapers created? I am not a good painter with brush. Is it possible to create digital arts with any software using own imagination? — Preceding unsigned comment added by 2405:205:602A:13F4:B5BB:2306:846F:85B8 (talk) 07:12, 11 September 2019 (UTC)

If you're not good at drawing, you probably don't want to use a program like MS Paint. You could also use a pixel editor to make some repeating small geometric pattern, like cubes, by setting the color of each pixel one at a time. For computer generated 3D images, there are programs that allow you to specify the location and attributes of larger basic geometric shapes, like cubes, spheres, cylinders, etc. See 3D modeling, ray tracing and texture mapping. You could also apply textures, colors, lighting, etc., to complex 3D objects they provide. But to actually create your own complex 3D image, like a person, would require a great deal of time and expertise, to make it look any good. Also, some programs, like ray tracing, require significant CPU time, so you may have to wait for it to finish processing. Anther option is to do a screen grab of some 3D image you like, such as the victory screen on a game you won. Or you could start from digital photographs (perhaps from your cell phone) and then modify the image(s). For example, you could create an image of somebody about to be squished by a giant falling domino, by combining images of the person and falling domino, at different scales.
Note that making 2D images look like they are 3D can be done with techniques such as perspective and 3D projections. If you have some particular type of 3D image in mind, we might be able to suggest the best way to make it. Also, do you already know how to set an image as wallpaper ? SinisterLefty (talk) 12:32, 11 September 2019 (UTC)
Blender, 3D Studio Max, Maya 3D, LightWave... You can do some 3D-like effects from 2D pictures with GIMP and Photoshop (depending on what you're trying to do). 93.136.122.4 (talk) 19:19, 13 September 2019 (UTC)

Setting maximum JSON length property on JsonSerializer[edit]

I've run into a problem at work. I am using ASP.NET Core to build a controller taking JSON requests. The controller method looks something like this:

[HttpPost]
public IActionResult DoStuff([FromBody] MyModelClass model)
{
  /* Do something with the model */
  return new JsonResult() { /* parameters */ };
}

which is then supposed to receive HTTP requests with the Content-Type header set to application/json. This works all well and good, but then I found out that some of the request bodies are several megabytes long, which causes an error that the body length exceeds the maximum JSON length. And I couldn't find any easy solution to set a new value for the maximum JSON length. I tried googling for it, and found plenty of pages advising me to set the MaximumJsonLength property. But that only works for JavaScriptSerializer, and the ASP.NET Core framework seems to use JsonSerializer instead, which doesn't appear to have this property.

In the end I found this page advising me to write a custom input formatter, and this appeared to work. I just replaced all of this weird "protobuf" stuff with a JavaScriptSerializer that I was able to set the maximum JSON length property to. But it appears that this has caused the loss of all the pre-made JsonSerializer functionality.

What my question here is, is there any easier way to do this? JIP | Talk 20:44, 11 September 2019 (UTC)

The opposite approach is to modify your code to return the data in smaller pieces, or only return those portions which have actually been changed. This isn't always possible, but when it is, it could solve your problem. If you can describe what the code does, maybe we can think of ways to break up this task. SinisterLefty (talk) 21:08, 11 September 2019 (UTC)
No, the problem is not with returning data, it's with receiving data. It's the incoming requests that are several megabytes long, not the outgoing responses. JIP | Talk 04:06, 12 September 2019 (UTC)

September 12[edit]

I accidentally deleted 10 files on my USB memory/storage chip by overriding their names. Are they lost for good, or are they retrieveable?[edit]

I accidentally deleted some files on a Lexar USB memory/storage chip by changing the filenames of some other files to the name of already existing ones and then I overid them. It was a stupid and clumsy mistake.

Since they were overriden with the same name by other files they did not go to into the trash (recycle bin). in fact, I think they probably wouldn't have either way, since they were only stored on the USB chip and not on the PC itself.

Is there any way I can retrieve the files? There were only 10 files, I believe, so if they still exist and can be found, it shouldn't be a problem to restore them one at the time, I think. I'm no ace on computers, but if it can be done with relative ease, then maybe I can do it, with some guidance.

Thank You Krikkert7 (talk) 19:03, 12 September 2019 (UTC)

It will very much depend upon your operating system and the filesystem in use. For hard disks the advice is to connect them unmounted and use a block-by-block copy utility to make an image of the disk before trying any recovery. I suspect that this advice is valid for memory sticks, but do not have a firm statement confirming that - in other words, proceed at your own risk. The standard tool on Linux and UNIX systems is dd(1). At a presentation on security that I attended recently we were told: "Create the image with dd. Windows is not forensically safe.", you are effectively doing forensics here. Once you've made a copy, remove the stick and don't connect it again. Work on a copy of the online copy, if you screw up you just make another copy! Try sleuthkit as a starting point. The bad news is that recovering deleted files is rarely "done with relative ease". Martin of Sheffield (talk) 19:30, 12 September 2019 (UTC)
@Martin of Sheffield: Would ddrescue be better than dd (on a *nix system)? Poveglia (talk) 20:23, 12 September 2019 (UTC)
Good point, the new kid on the block! I've personally not used it, but the write-ups seem positive, particularly for hard disks which may be failing. In this case though the copy should be clean since we are not dealing with failing disks and head crashes. Martin of Sheffield (talk) 21:09, 12 September 2019 (UTC)
I can vouch for the fact that ddrescue works but I haven't had a reason to try dd yet (and I thank all deities for that). Poveglia (talk) 21:40, 12 September 2019 (UTC)
@Krikkert7: In the past there was a suite of Norton utilities that would show you deleted files and let you recover all or parts of them. You could check to see if that product or something similar still exists. I agree with the above advice to work on a copy if possible. RudolfRed (talk) 20:00, 12 September 2019 (UTC)
Like Martin said, first its important to make a proper copy. We have a long list of data recovery software. I'd imagine Recuva has a large marketshare amongst windows users because it was created by the same company who make CCleaner. Only run the data recovery software on the copy, not on the original! Poveglia (talk) 20:20, 12 September 2019 (UTC)


Yeah it's probably not a big deal to use a file recovery tool to get the files back, especially if you can tolerate some file corruption (e.g. the file was a document you were working on, and a paragraph got clobbered but the rest is intact). Maybe someone can suggest specific ones. I used to know of a few but their names aren't coming to mind right now. 173.228.123.207 (talk) 20:21, 12 September 2019 (UTC)
  • If this is Windows, I would also suggest Recuva. Provided that you don't modify anything on the USB drive, I wouldn't even bother copying this first. Just run Recuva and let it do its thing, but recover the files to an area on your normal disk, not the USB drive.
If you knew how to make an appropriate bitwise copy which was itself recoverable, you wouldn't be asking me for advice. Andy Dingley (talk) 20:39, 12 September 2019 (UTC)
@Andy Dingley: Are there no easy to use Windows programs that can do that? I wouldn't be surprised if something like the HDD Raw Copy Tool would work. Another less-desirable option would be AOMEI Backupper Standard or even EaseUS Todo Backup. Poveglia (talk) 21:30, 12 September 2019 (UTC)
Recuva's about as easy as it gets. Andy Dingley (talk) 00:08, 13 September 2019 (UTC)
I know, I mentioned it above and I've used it in the past. I meant easy-to-use Windows programs that can make a "raw" copy of 1 usb stick and write it to another. Poveglia (talk) 00:35, 13 September 2019 (UTC)
If the user already happens to have Linux installed somewhere I'd absolutely recommend ddrescue first and Recuva second, there's no drawbacks to using ddrescue, while every minute the drive is mounted in Windows gives the OS extra chance to meddle and overwrite unallocated space. If the user doesn't have Linux then yeah just do Recuva. 93.136.122.4 (talk) 19:23, 13 September 2019 (UTC)


Thank you, guys. That was a lot more response than I expected. I'll try Recuva. It sounds like it might be the easiest thing to use. I have used/edited a few files since the accident, however. Not that many, but the point is that the USB has not been left untouched since the accident, if that matters... Krikkert7 (talk) 10:05, 13 September 2019 (UTC)

Yes, a rule of thumb in forensic data recovery is that the more a device is used after the data loss, the more difficult it may be to recover anything. In the future (other than keeping meticulous backup copies of your personal files, storing some off-site, and testing your restore and recovery procedures) the best thing to do might be to yank the USB drive ASAP, rather than a "safe removal" which would flush the write cache and nail the coffin shut.
I found a couple of good articles:
Our instructor sent us to HowToGeek when I was studying for the CompTIA A+ certification. It's a great source. Elizium23 (talk) 11:50, 13 September 2019 (UTC)

September 13[edit]

After win 10 update, can't see files[edit]

The latest Windows 10 update (1903, OS Build 18362.356) basically reset everything, as if I had a new computer. Most seriously, File Explorer does not display any files. I know they're there because Notepad++ can access them. How do I get File Explorer to recognize the files? Thanks. --Halcatalyst (talk) 14:03, 13 September 2019 (UTC)

I am 98% sure that Notepad++ uses CommonDialog Controls meaning that the Notepad++ Open file screen is using Explorer to display files.
If you hold down the Windows key, then tap the letter E and release the Windows key a new File Explorer window should pop up. Have you tried that? What happens? Can you make a screenshot or even a photo of the screen and upload it to a image sharing site like Imgur.com and share the URL here? You may also wanna try holding the windows key, pressing R and then releasing the Windows key. In the windows that pops up type the following: C:\ then press Enter.
Do you see the taskbar with the start menu button in the bottom of the screen? If not then explorer.exe needs to be restarted. Poveglia (talk) 16:02, 13 September 2019 (UTC) Poveglia (talk) 15:49, 13 September 2019 (UTC)
  • Try pressing F5. I've noticed this on some Win10 machines in the last week, mounting remote devices. They initially load an empty directory, but a refresh shows everything, as expected. Andy Dingley (talk) 15:57, 13 September 2019 (UTC)
  • Good point I've seen the same thing happen on local but external USB drives and F5 fixed it. Poveglia (talk) 16:03, 13 September 2019 (UTC)
  • Another fine alternative too. I recommend Q4OS. 93.136.122.4 (talk) 21:41, 13 September 2019 (UTC)

Thanks for your replies. Here’s the imgur URL: https://imgur.com/a/Re9gLAd

Windows E, C:\ and F5 continue to show empty. I do see the taskbar. --Halcatalyst (talk) 20:28, 13 September 2019 (UTC)

I poked around in Properties and found out that the empty directories were in c:\users\TEMP instead of c:\users\hal, where all is well. However, when I click on This PC, I get the empty folders again. How can I make File Explorer start at c:\users\hal rather than at TEMP? --Halcatalyst (talk) 21:26, 13 September 2019 (UTC)

Convert PDF back to Latex[edit]

Is there a tool that can convert a PDF back to Latex? I've got a PDF of a thesis that was obviously created in some sort of a Latex program. It looks something like this, but the text is single-column, so I'm thinking it should be easier to change it back. I want to turn it into a reflowable format like DOC or EPUB to read it more easily since it's set in a very small font which makes for long rows that are hard to read. Obviously there's OCR and the text can be copy-pasted but I'd like to preserve the formatting too (with as little manual editing as possible). 93.136.122.4 (talk) 19:05, 13 September 2019 (UTC)

PDF supports including bitmaps, and if the equations were bitmaps, then OCR would be the only option. But I looked at the PDF file, and I'm glad to say those don't appear to be bitmaps. That is, they don't look pixelated when I zoom way in, and I can highlight the equations one character at a time. So, theoretically, you should be able to convert back to LATEX without using OCR, if you can just find the right program to do it. SinisterLefty (talk) 20:38, 13 September 2019 (UTC)
Well yeah, the right program is what I'm looking for. Any ideas? 93.136.122.4 (talk) 21:39, 13 September 2019 (UTC)
I googled "PDF to Latex" and there were quite a few options. Maybe try Inftyreader? What operating system are you on? Poveglia (talk) 01:42, 14 September 2019 (UTC)
Thanks, InftyReader converts very well, unfortunately the full version is too expensive for me and I've got 150 pages to process, so 5 pages per day in the trial version won't do. What other suggestions do you have? (I have Windows and Linux) 93.136.122.4 (talk) 11:35, 14 September 2019 (UTC)
I'm surprised that it worked well. Last year when I did an automatic Word to TeX conversion (with another program), the results were unacceptable. But if it works well, the one-year version is $45 US, so even if you use it only for that, it is amounts to 30 cents per page. Bubba73 You talkin' to me? 17:05, 14 September 2019 (UTC)

September 14[edit]

MS Office installation[edit]

If I have a version of the 1-time non-subscription office software, I can obviously install it on my PC.

If I later rebuild the PC (format and reload the operating system from the recovery information), are there any issues with reinstalling the office onto the SAME PC? -- SGBailey (talk) 10:11, 14 September 2019 (UTC)

If you are referring to a recent version of Office such as Microsoft Office 2019 or Microsoft Office 2016, I do not foresee any significant barriers to this. Office uses online electronic activation, so you will need to make absolutely sure that you have retained the product key code and the installation media, so that you can restore the software and re-activate it (which should be as simple as clicking through a wizard in the application itself.) If you have lost the product key, apparently there are applications which are capable of scouring the filesystem in search of it, but that only works if you haven't wiped the HDD first. Elizium23 (talk) 05:35, 15 September 2019 (UTC)
Thanks -- SGBailey (talk) 07:22, 15 September 2019 (UTC)

September 15[edit]