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April 11

Why is there no article on ClueBot NG?

Why don't MartinBot, Cluebot, BetaCommand, CBNG, and AntiVandalBot have their own articles? They are notable, the BBC, the Verge, and many other mainstream news outlets have written articles on them. Is there some policy preventing the glorification of bots, lest they be deified and all editors turn from the Light? Thanks L3X1 (distant write) 01:19, 11 April 2017 (UTC)[reply]

Most likely because you haven't written those articles yet. StuRat (talk) 01:32, 11 April 2017 (UTC)[reply]

Nice, pinning the blame on me. :) L3X1 (distant write) 01:36, 11 April 2017 (UTC)[reply]

StuRat Actually, it doesn't exist because only admins are able to create the page, and none of them are so inclined. In 2010 the first it was deleted, the reason was "Wikepedia hardly needs an article on its own editing tools". However, IAR, I will draft an article and submit it, later. L3X1 (distant write) 01:55, 11 April 2017 (UTC)[reply]

I'm just going to hazard a guess that Cluebot doesn't meet GNG. <does a google news search> Okay, I was wrong. Yup. GNG passed, hammerpants approved. I'll watchlist it and start helping when you move into article space. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 12:10, 11 April 2017 (UTC)[reply]

April 12

calculate angle on image

Is there a way to calculate the (approximate) angle at which these two thick black lines meet[1]? Doesn't have to be precise, plus minus 2 or 3 degrees is fine. ECS LIVA Z (talk) 00:19, 12 April 2017 (UTC)[reply]

Slap a protractor on it and read the answer. StuRat (talk) 01:06, 12 April 2017 (UTC)[reply]

The upper line is 45.48 degrees. The lower line is 74.41 degrees. Open the image in a photo editor (I used Gimp) and use a measuring tool to calculate the angles. The angle between them is 28.93 degrees. 71.85.51.150 (talk) 01:07, 12 April 2017 (UTC)[reply]

Uh wait, the angle between them is clearly more than 90deg.

Sturat's "slap a protractor on the screen" method gives me roughly 140deg (Perhaps you subtracted when you should have added?) ApLundell (talk) 02:06, 12 April 2017 (UTC)[reply]

The IP just gave the outside angle, while you got the inside. I checked both ways (inside and outside) and got 29° and 151°. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 02:15, 12 April 2017 (UTC)[reply]

They will add up to 180° so if you measure one you can calculate the other. If your measuring tool doesn't do angles, you can still possibly get the pixel coordinates and then figure out the angles with trigonometry. 50.0.136.56 (talk) 16:35, 12 April 2017 (UTC)[reply]

Local machine IP extended to a virtual machine cause conflict?

I have a local machine with Win10 from which I mean to run a Linux virtual machine (LVM) with an OpenSSH server (there is a reason why I consider an LVM instead of WSL, in this case). Now, here's what I want to ask:

I have my IP address which is permanent. As far as I know, this IP comes from my ISP, and due to that, if I'll install an LVM on my local it will have the same IP as the host machine.

Let's assume I have the same IP both on the host machine and LVM: How then could I SSH tunnel into both without creating some kind of conflict? That is, both has the same ISP-provided IP address, so how could I avoid conflict? Ben-Yeudith (talk) 04:53, 12 April 2017 (UTC)[reply]

You can not have the same IP address on both of them. Your LVM will have a different IP probably in a 192.168.*.* range. Then either the host OS or your wi-fi router (if you use one) will translate it into the external provider assigned IP. Ruslik_Zero 08:42, 12 April 2017 (UTC)[reply]

In terms of enabling remote SSH, these easiest thing to do is probably to choose different ports for the SSH in each computer and make sure you set up port forwarding correctly. I'm assumign you're not behind CGNAT or anything else that will make things difficult and either your router or host OS (whichever is reponsible, or both) supports forwarding properly. Nil Einne (talk) 09:44, 12 April 2017 (UTC)[reply]

Yes, port forwarding is the answer. Your LVM will configure a virtual network interface that will listen for traffic on your host machine's localhost and forward it as appropriate. On VirtualBox, you can do this with the Network Address Translation option on the guest machine: I like to set it up to forward an otherwise-unused port such as 2222 for my OpenSSH server on the guest.OldTimeNESter (talk) 13:11, 12 April 2017 (UTC)[reply]

ǂ

ǂ is a redirect to Palatal click, a kind of sound in some click languages that's typically transcribed with this character. What other uses does this character have? In MARC records, it's used to set off subfields, e.g. the standard LCSH for crime in Providence RI might be Crime ǂz Rhode Island ǂz Providence, and substituting other characters, e.g. ‡, will confuse the relevant software. Given these two radically different usages (and the fact that it's not a standard keyboard character, with no "normal" meaning), I'm wondering if it might be the standard character for other purposes as well, but aside from palatal clicks and MARC references, all I'm finding with Google are mojibake and idiosyncratic uses, e.g. this person's Twitter page. Nyttend (talk) 22:35, 12 April 2017 (UTC)[reply]

The Unicode name for that character (U+01C2) is LATIN LETTER ALVEOLAR CLICK [2]. So it seems the click is the intended normal meaning for the character. CodeTalker (talk) 15:45, 13 April 2017 (UTC)[reply]

Thank you. Nyttend (talk) 00:08, 14 April 2017 (UTC)[reply]

I don't think that's a normal MARC thing, even. Maybe some specific software uses it. MARC codes usually look like $a, $b, etc. The character is also called "double-barred pipe" and almost all the ghits are about the Unicode or IPA phonetic usage. 50.0.136.56 (talk) 23:51, 13 April 2017 (UTC)[reply]

Interesting. Where have you seen $ used as the subfield indicator? ǂ is the indicator in OCLC Connexion, and I think it's the indicator in Voyager Cataloging; I can't figure out how to get MARC details from WorldCat, and many libraries just use | to separate subfields in the public-facing sides of their catalogues, e.g. [3], [4] (those first two links might not persist), and [5]. Nyttend (talk) 00:08, 14 April 2017 (UTC)[reply]

See for example here unless I'm confusing something. Web version of that record is here 50.0.136.56 (talk) 19:41, 16 April 2017 (UTC)[reply]

April 14

Can Google Maps list locations of two chains at once ?

Let's say I want to eat at Outback, then have dessert at Baskin Robbins. Can I list their locations, both on the same map, so I can find the closest set ? StuRat (talk) 17:18, 14 April 2017 (UTC)[reply]

You can search using OR as in "Outback" OR "Baskin Robbins". My experience is that you must place each place name in quotes and you must use a capital OR, not a lowercase or. 209.149.113.5 (talk) 18:14, 14 April 2017 (UTC)[reply]

Thanks, that worked ! I was using AND without quotes, with no luck. StuRat (talk) 18:34, 14 April 2017 (UTC)[reply]

Resolved

return to question about system of quadratic equations and NP-complete

The other day (now archived) there was a question that if you are given a system of quadratic equations that has either zero or one solution, is determining that NP-complete? This is for a system of quadratic equations in one variable, right? If so, isn't this linear in the number of equations? Take the first two equations, f and g. There are at most two points, x, such that f(x)=g(x). Plug this (or these two) values into the rest of the equations. Then it is easy to determine whether or not the solution (or two solutions) satisfy the rest of the equations or not. Bubba73 ^{You talkin' to me?} 20:34, 14 April 2017 (UTC)[reply]

Shouldn't this Q go to the Math Desk ? StuRat (talk) 21:27, 14 April 2017 (UTC)[reply]

The original was in computing Wikipedia:Reference_desk/Archives/Computing/2017_April_8#Qudratic_Equations_-_Promise_Problem (it is a computing problem). Bubba73 ^{You talkin' to me?} 00:06, 15 April 2017 (UTC)[reply]

April 15

Physically reading Stored information

When the computer reads a RAM or microchip address, what does physically read the address? I assume there's no physical needle or moving parts inside there. — Preceding unsigned comment added by 31.4.147.242 (talk) 14:18, 15 April 2017 (UTC)[reply]

You are correct that there are no moving parts as there are in hard drives. The addressing is all electronic. See Address bus. Dbfirs 15:16, 15 April 2017 (UTC)[reply]

The quick version is: It's all controlled by entirely electrical switches. When the correct sequence of switches is 'flipped', the only accessible part of the memory is the one holding the data your program is looking for. That sequence is then known as the memory address. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 18:11, 15 April 2017 (UTC)[reply]

here's a simple model of a 4-bit dynamic RAM. Basically, the address decoder logic selects which of the memory cells is connected to the input of a reading amplifier. Writing a 1 to a cell puts a certain voltage across that cell's capacitor, charging it, while writing a 0 shorts it to ground and discharges it. After a certain time (~300ms simulated time), however, the cap discharges via the mosfet, anyway, because the reading amplifier has a finite input impedance (and the voltage tends to equalize across all of the caps because they're all in parallel, mosfet notwithstanding.) That's where refresh comes in - were one to toggle the refresh switch quick enough, that would put the output voltage from the reading amplifier across the cap, preserving the cell's state (a bit like a missing pulse detector.)

It's all simpler yet in a static (as opposed to dynamic) RAM in which the memory cells are pairs of transistors that can stay in one state indefinitely without a need for refresh Asmrulz (talk) 08:46, 16 April 2017 (UTC)[reply]

April 16

HDD’s Volume Graphics

I wish to change the blue colour of the bar but keep the graphic intact of the windows 7 "Computer" folder's HDD’s volume graphics, what software(s) do I use? 103.67.156.75 (talk) 05:19, 16 April 2017 (UTC)[reply]

For clarity, you mean in Windows Explorer itself rather than in a screenshot? Nil Einne (talk) 08:02, 16 April 2017 (UTC)[reply]

[6] 116.58.201.130 (talk) 15:52, 16 April 2017 (UTC)[reply]

Handheld Device 1

Basically, I’m looking for a device that behaves, possess hardware and software exactly like a PC (desktop/laptop), I also wish to use the same device as a normal phone (ingoing and outgoing) without any strings attached, if you know what I mean.

For example, Phone style comes first, meaning, I wish to keep the simcard inside the device just like people keep simcard inside their phone, for ingoing and outgoing calls, to use internet... Secondly, I'm doing PC stuff in it or using it like a normal PC (for easy file transfer/management reasons) without worrying of, that I have to plug or unplug my internet dongle, or turn on a software in order to keep the phone or internet line active, if you know what I mean. Please, refer a good device as an example.

43.245.122.69 (talk) 15:50, 16 April 2017 (UTC)[reply]

Handheld Device 2

An interest in a phone(s) with PC (desktop/laptop) functionality, not looking for an iphone or android...doesn't meet the criteria.

43.245.122.69 (talk) 15:50, 16 April 2017 (UTC)[reply]

What specifically do you need not covered by iOS or Android. On my Android phone I have Word, Excel, and PowerPoint. I have a pdf viewer. I also have a terminal that lets me work on my computer cluster at work to edit code and submit jobs to the farm. I can Skype and have Slack. So I'm wondering what functionality these two os's lack that you require? There's the obvious down side in that they don't have a full size keyboard, but that's the same for all these devices. Dja1979 (talk) 17:54, 16 April 2017 (UTC)[reply]

Nokia N900? 50.0.136.56 (talk) 19:48, 16 April 2017 (UTC)[reply]

programming language logo

[7] appears to be the logos of 6 different programming languages. Clockwise from top: Python, Ruby, C++, Java, Javascript--but what's the 6th one, that looks like a shield with a 5 or an S in it? Thanks. 50.0.136.56 (talk) 19:47, 16 April 2017 (UTC)[reply]