A step in the proof of existence of least upper bound

Let $E$ be a non-empty subset of $R$, let $n \geq 1$ be an integer, and let $L < K$ be integers. Suppose that $\frac{K}{n}$ is an upper bound for $E$, but that $\frac{L}{n}$ is not an upper bound for $E$. Show that there exists an integer $L < m \leq K$ such that $\frac{m}{n}$ is an upper bound for $E$, but that $\frac{m-1}{n}$ is not an upper bound for $E$.  The author has given the hint to use cntradiction and then induction to prove but I am not able to make any progress on this question.  It is a step in the proof of existence of least upper bound.  (Reference: Analysis 1, Terrence Tao, Exercise 5.5.2, page 121)


The Twin Paradox involves 2 observers, usually twins. Let them be named A and B. A remains at rest in the same reference frame as Earth while B is in a separate reference frame moving at velocity v, close to the speed of light, from A. After a certain amount of time, B switches reference frames to another which moves at the same speed but in the opposite direction, towards A.   Generally, we would say that due to time dilation, B would have aged less than A. However, consider the case where B is stationary and that the Earth together with A are moving similarly and changing reference frames. In this case, A would have aged less than B.  These 2 cases should both be equally valid through the observations of A and B. However, this would cause a contradiction in how they have experienced time.   Please enlighten me on how this is resolved where A ages more than B. I would like to find out if I have made any misconceptions in my understanding.


Is "only if" different from "if and only if"?

From a linguistic standpoint, "if and only if" kinda sounds like an angry mother overexaggerating the "if", but mathematically this is not the case. Of course, this is completely irrelevant, I'm just trying to be funny.   I was told that "only if" is different from "if and only if". Instead of opening a Mathematical Logic book and looking through the definitions and proofs, I decided to take the easy route and ask here. If $p$ holds "only if" $q$ holds, shouldn't that mean that if $p$ holds then $q$ also holds, thus making "only if" the same as "if and only if"? Are these the exact same thing but we just ended up using "if and only if" predominantly?


How to Store HTTP Request Code in separate class for Reusability?

We have JSON HTTP Post request that triggers from  one salesforce object to external system and we want to extend this functionality for other object. This code Fires and creates a Record in external system when the criteria matches. We want to have this functionality on other object in salesforce. I know we can Reuse the code and I don't want to end up creating another Class that does the same thing for different criteria. how do I store HTTP Request in separate class/method and Call out that whenever I need to Here is the code public class RadarUpdate { @future (callout=true) public static void postcallout(string Id) {  //querying patient relations record Patient_Satisfaction__c c = [select id,Name, Patient_First_Name__c,Patient_Last_Name__c, Reporter_Phone__c,Reporter_First_Name__c,Reporter_Last_Name__c, Reporter_Email__c, Description_of_Feedback__c from Patient_Satisfaction__c where Patient_Relation__c ='Referred to Privacy Office' order by lastmodifiedDate desc limit 1]; //generating JSON  JSONGenerator gen = JSON.createGenerator(true); gen.writeStartObject(); gen.writeObjectField('name', c.Patient_Last_Name__c + ', ' + c.Patient_First_Name__c); gen.writeObjectField('incident_group_id', 7448); gen.writeObjectField('description',c.Description_of_Feedback__c); gen.writeFieldName('submitted_by'); gen.writeStartObject(); gen.writeStringField('given_name',c.Reporter_First_Name__c); gen.writeStringField('surname', c.Reporter_Last_Name__c); gen.writeStringField('phone',c.Reporter_Phone__c); gen.writeStringField('email',c.Reporter_Email__c); gen.writeEndObject(); gen.writeFieldName('custom'); gen.writeStartObject(); gen.writeStringField('TRIPSS ID',c.Name); gen.writeEndObject(); String jsonS = gen.getAsString();  System.debug('jsonMaterials'+jsonS); //generating Http request Http http = new Http(); HttpRequest request = new HttpRequest(); request.setEndpoint('https://api.radarfirst.com/incidents'); request.setMethod('POST'); request.setHeader('Content-Type','application/json;charset=UTF-8'); request.setHeader('User-agent', 'Salesforce-integration-client'); request.setHeader('Authorization','Bearer eyJhbGciOiJSU0'); request.setBody(jsonS); // Set the body as a JSON object HttpResponse response = http.send(request); if (response.getStatusCode() != 201) { System.debug('The status code returned was not expected: ' +     response.getStatusCode() + ' ' + response.getStatus()); } else { System.debug(response.getBody()); } }  }


I have the following table: Red: 4 Green: 3 Red: 6  If i want to make excel skip rows and only sum the reds (so red sum is 10) - which formula can I use? Thanks for your help!


Here was my argument against this, the second law of thermodynamics, in effect says that, there is no heat engine that can take all of some energy that was transferred to it by heat and do work on some object. So, if we can not take a 100% the thermal energy of an object, and use it to do work, what about the thermal energy that is rejected to the environment, can we use all of that energy to do work on an object? No, if energy is supposed to be the ability to do work, well that’s a contradiction.


Prove that: $$(x_1+...+x_k)^2\leq 2(x_1^2+...+x_k^2)$$ for all $x_1$, ... $x_k\in\mathbb R$. Is it also true that $$\left|x_1+...+x_k\right|^2\leq 2(|x_1|^2+...+|x_k|^2)$$ for all $x_1$, ... $x_k\in\mathbb C$?  My attempt for $k=2$. $$(x_1-x_2)^2\geq 0, \ \ \Rightarrow\ \ x_1^2+x_2^2\geq 2 x_1x_2$$ Then $(x_1+x_2)^2=x_1^2+x_2^2+2 x_1x_2\leq x_1^2+x_2^2 + x_1^2+x_2^2$ so I think we can prove the first statement by the induction principle. Is true the second statement?


Add comment length counter on the mobile site

I know that comments have to be at least 15 chars for the system to post it. I noticed that on the mobile site, there is no "x chars to go..." warning.  If I try to post a comment that is too short, it silently fails and still no mention of minimum length at all.  Can the length counter that is present in the full site theme be added to the mobile theme please?


I've been admitted to multiple PhD programs, how should I choose between them?

I've been admitted to more than one PhD program, and I'm having a very hard time making a decision.  The programs I'm accepted to have advantages and disadvantages with respect to one another. How do I weigh the relative importance of difference aspects of the program in order to make an optimal decision?  Ultimately, this is not a decision that anybody else can make for me, because everyone has different values and priorities, and the right decision for me may not be the right decision for somebody else. However, you can help  by giving me more information about how different features of a program will affect my experience in graduate school and my future career.  The offers under consideration differ in a variety of ways:          I need to know more about what kinds of things are important and how these will affect me, so that I can make an informed decision about balancing competing criteria.     Note to readers: These answers quote extensively from other answers on this site (and link to them). If you read something quoted here that you find helpful, please follow the link to the original source and vote it up!    This is a special community wiki 'canonical' question that aggregates advice on a very broad topic - see more information in this .  Each answer here relates to a different metric that one might take under consideration. If you have a new "critical" metric not in the list above that you believe should be an important part of the decision, post a new answer. If you want to add something related a metric that's already represented in its own answer, edit that answer.


Factorizing n in given number of factors such that value of maximum factor is minimized

Say I have 12 and have to factorize it in 2 factors. Now possible factors are 1, 12 2, 6 3, 4   Now 3,4 is such that value of maximum factor i.e. 4 is minimized among all pairs.  How to find the solution in generic case where a number N is to be divided in K factors minimizing maximum value.


I've got custom content-type with several groups and fields.   I want to change default display of that content-type. In which file can I find appropriate code?


I want to set it so that the Windows 10 tiles for things like Candy Crush do not appear for users logging in to a machine. This is on a fresh 1909 install.  I understand that these apps aren't installed as such, I just want to hide that tile.  information here -  suggests editing registry keys at   HKU\Default_User\SOFTWARE\Microsoft\Windows\CurrentVersion\ContentDeliveryManager  However I don't have this 'ContentDeliveryManager' folder. I'm finding that other similar solutions have similar results - I don't have the same registry keys!  Does anyone have any advice?


Can I invoke Google to check my robots.txt?

I read the answers in this question, but they still leave my question open:   I didn't find a way in the Google Webmaster Tools to invoke a re-download of my robots.txt.  Through some error, my robots.txt was replaced with:  User-agent: * Disallow: /   And now all my content was removed from Google search results.  Obviously, I'm interested in correcting this as soon as possible. I already replaced the robots.txt, but I can't find a way to make Google update the cached version.


The sum of % in the CPU column doesn't match the total CPU % row


I have a on-off switch that'll use for a kill switch for my car using the gas pump. The switch says 6A/125V 3A/250V 22 AWG. For my purpose it needs to handle 12V 20 Amps max.


Prove $ \sum \frac{cos(n)} { \sqrt n}$ is bounded

Prove $ \sum \frac{\cos(n)} { \sqrt n}$ is bounded.  How can I prove $\sum \cos(n)$ is bounded. Can It be done using $\cos$ as real part of complex number as I showed in question ?


define two dimensional array in c# with string indexes

How can I define something like this in c#:  list["alpha","beta"] = value;   And I want to access values such as dictionary:  var item = list["alpha","beta"];


Does the maximally-extended Schwarzschild horizon see the entire past of the parallel universe?

I've seen similar discussions for the inner horizons of Kerr and Reissner-Nordstöm metrics, but I've never seen mention for the simple maximally extended Schwarzschild geometry: As an infalling observer coming from one of the exterior regions (U) crosses the future horizon of the black hole, does the observer start seeing the entire history of the other exterior region (U')?         I+ ~~~~~~ I+          /\    /\         /  \  /  \     I0 /    \/    \  I0        \ U' /\ U  /         \  /  \  /          \/    \/        I- ~~~~~~ I-   In the Penrose-Carter diagram for the spacetime, null geodesics starting at past timelike infinity in the other exterior region would just "ride along" the white hole horizon (bottom-left I- to top-right I+), which is the black hole horizon on the future that our observer crosses; any light emitted later than at past infinity would meet the infalling observer a little further on her way into the interior region.  If this is the case, would that mean that the energy density at the future horizon is infinite and that the horizon should be unstable (notwithstanding the fact that this metric models empty space)?  (Similar energy divergence has been described and analyzed at the inner (Cauchy) horizon of  the other, more complicated black-hole geometries that feature time-like singularities.)


Hi I have a JSON Object   var A = {"Name:""Abd'Allah", "Age":43, "Homeland":"Australia"};   Now I copy to B and add/delete/modify some attributes  var B = A; delete B.Homeland;   Now the issue is when I deleted the value from B, it got deleted from A as well. Why? How JSON  variable got copied?   Currently what I am doing is   var B = JSON.parse(JSON.stringify(A));   But this is kind of stupid. What is the right way to do it?


Why isn't the 16.04.1 Point Release available via update manager?

The point release is out but the update manager set to identify LTS releases gives no hint of 16.04.1.  Also setting update manager to "any release" only gives the option for 15.10. Point release was released on 7/21/16.  Today is  7/27.  Is this timing normal?  Is 16.04.1 not a viable LTS? Other threads indicate that a manual acquisition of 16.04.1 is possible.  If the point release bits are out there but update manager doesn't show it via the LTS option is 16.01.4 not a viable LTS?


Learning terminal by observing commands being run by GUI

Hello I'm new to the Linux system and would like to know if there is a code or application which opens a terminal that will tell me the lines of code being used.  For example, If I were to open a folder or directory I would like to know the lines of code associated with it.


Using gravity to send messages (at the speed of light)

I've been wondering what the current state of the art (both theoretically and practically) for sending messages using changes in a gravitational field is, and I have had a hard time finding information about it online. I've seen the Wikipedia page on gravitational waves, but it seems that gravitational waves per se are not yet practical as a communication medium, since they have yet to be detected.  However, a different (unoriginal, I know) idea is simply to cause a change in a gravitational field from some point, and measure the change at another. You could encode the magnitude and/or frequency of the change into bits and communicate wirelessly. Although this is still subject to the speed of light, it has other benefits over radio communication like easily penetrating all matter.  A particularly slow and inefficient implementation of this might be to attach a large number of powerful rockets to the moon and alter its velocity enough that it changed the timing of ocean tides in a measurable way.  How far can we extend this? Can I build a gravitational detector sensitive enough to measure a bowling ball oscillating near it? How about from the other side of the earth? How little mass can I use?  Can I do it without any mass at all? We know that massless particles are still affected by gravity, and I believe we also know that massless particles have their own gravitational field (in accordance with mass/energy equivalence). Can we exploit the gravity of massless particles to generate high frequency changes in a gravitational field without having to worry about inertia? Can we then use the high frequency of these oscillations to isolate them from the high level of noise generally present in low frequency gravitational detectors?


I would like to get time in below format 2020-10-12 10:41:42,526   How can it be done. I tried this but looks not correct date +"%Y-%m-%d %H:%M:%S,%N"


How do I get common file type icons in C#?

As seen in  for common file types, it's quite possible for a windows program to get the icons for a registered file type using the C++ Shell API.  These icons may or may not exist on disk - for example, we wanted to make our own custom file browser and want to display the system-associated icon with the file.  Is there a native C# way to get the icons for various file types (and if so, how) or must it be done through PInvoke with shell API?  And as a follow up, if there is a native .NET way of doing it, is there a cross-platform way of doing it?


What is an intuitive explanation for $\operatorname{div} \operatorname{curl} F = 0$?

I am aware of an intuitive explanation  for $\operatorname{curl} \operatorname{grad} F = 0$ (a block placed on a mountainous frictionless surface will slide to lower ground without spinning), and was wondering if there were a similar explanation for $\operatorname{div} \operatorname{curl} F = 0$.


Can I put a 24x3 inch tire on a rim that is normally for a 24x 2 1/4 inch tire


How do I move a point without affecting other points/plains?

I have extruded a plane many times, and I want to grab and move one point to change the shape of a paticular plane, but when I attempt to do this, It affects all planes in the figure. How can I fix this?  Unexpected Result: ()


What do you call a person who dislikes something just because it is trendy?

I'm trying to describe someone who no longer favor something simply because more people are aware of it/like it now.   Possessive and selfish come pretty close but still not quite what i'm looking for.


Be able to edit a vote on an answer if the question is changed

Here's what just happened:   Question: "How do I do X and Y, I can't use flash" Answer: "Well, use this flash player!" I downvote the answer saying "yeah you're right, but the OP said no flash so -1" The OP changes his question "edit: lololol in the end I can use flash" I can't edit my vote unless I make a "fake" edit on the answer Fail   Why not allowing changing vote on an answer if the question is edited?


Why is emptying the trash so much slower than rm?

If there are a lot of files in the trash, sometimes the Finder will display a progress bar saying (for example) "Preparing to delete 62,736 files", then another progress bar for the actual deletion. By comparison, deleting those same files from the command line is nearly instantaneous.   What is the Finder doing that takes so long? Is it detrimental to my system to skip that by deleting files via rm?


New business name and website - old site has 200+ backlinks - What to do?

For legal reasons I had to change my business name, and get a new site name and address (very long story).  I had to forward my old domain to this new one, but the old domain has like 200+ back-links, and the new site has zero. How does this impact SEO and what do I do in a situation like this? Do I start from scratch, or is there a way to capitalize on those back-links on the old domain name?


Software Installation Error in Ubuntu 16.04 LTS

My Ubuntu version is 16.04 LTS and when I am installing any external softwares like Meld in my Ubuntu it is giving the error:   E: The package uno-libs3 needs to be reinstalled   but I can't find an archive for it.


How do I make cartographic maps with relief and color?

I am trying to make a cartographic map like this, I have the qgis software, base layers, and Dem available. What will be the workflow which I need to proceed to make maps like this?


I was watching an English teaching video, they said:     How often do you go to the Cinema?   And after a while, they said:     How often do you go to work?   Why they didn't use the definite article the before work?


I (Slarty) appear to have two entries in the weekly reputation score listing


How to install Ubuntu 18.10 to an UEFI system with Windows 10

I did a lot of search but things looked very complex, I just cannot believe it will be such difficult.  So I think some tutorial may be written long time ago and thing could already became easier. To be pretty clear what I should do, I have to raise this maybe duplicated question.  I am a Slackware user, had no experience in Ubuntu.  I just got a new laptop installed with Windows 10. I then bought a new SSD disk for it and decided to install Ubuntu 18.10 onto this new disk and dual boot the laptop along with the existed Windows 10.  The windows 10 is booted by EFI and I've already disabled 'fast boot' in Windows.  I dumped (dd) the Ubuntu 18.10 to an USB stick and booted it to execute the installation.  I did not see any options like 'install alongside windows', so I choose to manually create partitions and told the installer the mount points. Of course, I did every thing on the new disk, did not change anything on the old disk that hosted Windows 10. Basically, I created three partitions, one for root, one for home and one as swap.  The installation went so smooth and it can even detect the Internet connection. Just after a while, the installation completed.  But the real problem I met is, there is not a new EFI boot option after reboot the laptop. Whatever I tried, it seemed like I've already installed the Ubuntu, but just cannot boot it.  What should I do?  Some net tutorials said I have to erase everything and install Ubuntu first, this is not an option to me. I can erase the 2nd disk, but cannot damage the first disk, because this is my company's computer. IT department will not install Windows for me after the laptop has already installed a Linux.  Please someone help. Thanks. woody


Syntax highlighting for form elements sometimes do not work

I  that has this code  <input type="text" v-model="myVar" @keyup.enter="doFilter" /> <button class="md-icon-button md-raised md-accent md-dense" @click="doFilter">Filter</button>   and it does not work unless I add in this  <!-- language: lang-html -->   Is that a bug?  Update 1: Example of code section not working  Here is the exact 2 lines from above, without the syntax highlighting hint   Filter  I cannot reproduce it when I indent the code here. Is there a stackoverflow sandbox where I can create a test question?


Find the side of an equilateral triangle given only the distance of an arbitrary point to its vertice

Triangle ABC is an equilateral triangle and P is an arbitrary point inside it. The distance from P to A is 4 and the distance from P to B is 6 and the distance from P to C is 5. How to find the side of an equilateral triangle from this information?  $$\frac{a^2+x^2-y^2}{2xa} = \frac{\sqrt{3}}{2}\frac{a^2+x^2-z^2}{2xa}+\frac{1}{2} \sqrt{1- \Big(\frac{a^2+x^2-z^2}{2xa}\Big)^2}$$  @Aditya  based from that equation where did you get   that square root of 3 over 2 ....up to   ...... plus one half then square root of 1 minus something and so on.. pls explain further


Wireless Client (Laptop) unable to connect to domain (windows server)

I have established a server in the office using Windows Server 2008 R2 and Active Directory. And then created several users in Active Directory Users and Computers.  The PC users can successfully join the domain and log in using their username/passwords.  However, the laptop users with wireless connectivity are not able to join the domain and access the network. I checked laptops with ethernet cable, and they successfully logged in to domain. But when unplugging the ethernet cable and enabling the wireless, they cannot log in to domain any more.  How can I enable domain access for wireless clients?  If the problem is with DNS or DHCP, then, why does a laptop connect to domain with Ethernet cable, but not with wireless connection (with the same exact DNS configurations) !!!? The only difference is being connected wired or wireless !! Am I wrong !!?    Edit 1  We are using a D-Link 2750U ADSL Modem which has 4 ethernet ports and wireless enabled. We use this modem both for accessing the internet, and also for establishing the server-client network. The server PC is connected via ethernet cable and has Windows Server 2008 R2 running, while the clients are some PC and some laptop, mostly Windows 7.  Edit 2  I tried the ping example.local command in laptops. When connected with ethernet cable, it has nice and successful reply; but when connected via wireless (WLAN), the ping does not respond, and gives the following error: "Ping request could not find host example.local. Please check the name and try again."  Edit 3  It seems that I have to enable something in the server or active directory, so that wireless clients can find, connect, and access the server.  Edit 4  This is what I've done to the DNS settings of clients (both wired PCs and wireless laptops): In the properties section of IPv4 (in client computers), I choose the Use the following DNS server addresses, and in front of Preferred DNS server, I type the IPv4 of the server PC. This works perfect for wired PCs, but not for wireless laptops.  Edit 5  Unfortunately, we do not have static IP. So we are using dynamic IP (for both server and clients). Is it possible to configure DNS and DHCP with dynamic IP?  Edit 6  The following pictures show the Network Connection Details for both the Server and the wireless Client:          Edit 7  I tried ping 192.168.1.34 with wireless laptop. The result was request time out, followed by trying to connect to 192.168.1.33 (!!), which again resulted in request time out.  It was really strange. So I tried ping 192.168.1.35 from wireless laptop. It replied successfully, but with 192.168.1.33 IP !!!!  The 192.168.1.33 IP belongs to another win-7 PC in the office, which used to host the shared drives and shared printers when we used win-7 homegroup (instead of server) in the past.  Edit 8  I checked the IP of the computers again. They have changed. The Server PC is now 192.168.1.35 and the wireless laptop is 192.168.1.33  Edit 9  I'm not able to ping the wireless laptop. Right now, the laptop's IP is 192.168.1.36, and when I do ping 192.168.1.36 from server PC, it says Destination Host Unreachable !! However, the wireless laptop is able to connect to internet with wifi.  Edit 10  I tried 192.168.1.1 in a web browser with the wireless laptop, and it worked successfully. The browser opened the D-Link Modem page.


Does anybody know the names of galaxies in Star Wars?

I'm trying to find out what is the name of galaxy where Coruscant and other planets are located. Like for example our galaxy is Milky Way, what's the name of that galaxy? I'm trying to find out, but I failed in my search, I hope that someone knows what it's name is.


I have a computer with Windows XP installed.  My user does not have a password.  When Windows starts, it goes to the login screen. Because my user has no password, is there any way to bypass this screen, and log in automatically?


How to calculate a Cartesian product of a list with itself

For example,   list = [0, 1, 2]   I want a list of all possible 2-combinations:  combinations = [(0,0), (0,1), (0,2), (1,0), (1,1), (1,2), (2,0), (2,1), (2,2)]   It seems to me that all the tools in itertools in Python only make one of (1,0) and (0,1), not both, I need both. Any suggestions, other than entering them by hand?


Image descriptions are very rarely written in by users

I have noticed that although when inserting an image part of the code that SE Inserts when you upload it is text saying "Enter image description here" but people very rarely put  image descriptions and that is really annoying for blind people.  I think it may be because not everybody who asks on a SE Site is techy and only some people will even think of modifying that code.  I think you should make entering the image description a required thing so that people don't just overlook it.  It's just so annoying having to always post comments like "What does that image show?", "What would you describe that image as?", etc...  Any help would be appreciated.


Delete symbolic link to c:\ when not being able to access c:\

I know how to create and delete symbolic links, but now I have a specific problem. I wanted to create a symbolic link from c:\mydata to d:\mydata, but forgot the first parameter, so I entered from c:\:  mklink /D d:\mydata   The command created a symbolic link c:\ to d:\mydata. The link is working :-) but now I cannot access my c: drive, because it is mapped to d:\mydata. I don't know how to remove this link, can anyone help?  All the answers under the question  do not help me, because:   I cannot delete c:\ in windows explorer, because there ist no delete option on drive c: I cannot open the shell with admin privileges to execute rmdir c:\ (I'm always getting an error message when clicking right on "shell" and choosing "run as admin" ("...system32\cmd.exe could not be found")   Update: My system is still running, I can log out and log in, but I'm afraid of rebooting it. It's running since I made the mistake. I can use most of the programs, only a few (like Adobe Reader or opening an admin shell) are not working.


Is it possible to die while wearing the Cloak of Invisibility?

At the end of Tale of the Three Brothers, it reads:     But though Death searched for the third brother for many years, he was never able to find him. It was only when he had attained a great age that the youngest brother finally took off the Cloak of Invisibility and gave it to his son.   From this passage, can we infer that you cannot die while wearing the Cloak?


I'm wondering how to combine two integer like this  vector <int>  A = {3,4,5}; vector <int>  B = {100,102,103};   and then can we have a fast way or a funtion that can help to attach the vector B to vector A and vector A then look like this :  A = { 3,4,5,100,102,103}


Run sudo commands without running the whole script with sudo (using a desktop launcher)

My script is something like this:  #!/bin/bash sudo teamviewer --daemon enable teamviewer sudo teamviewer --daemon disable   It works fine on its own, and it requests my password with a terminal window. So, now I want to make a launcher for it. I have this in my .desktop file:  [Desktop Entry] Version=1.0 Encoding=UTF-8 Type=Application Categories=Network; Name=TeamViewer 12 Comment=Remote control and meeting solution. Exec=gksu /path/here/Start.sh Icon=teamviewer   That way it requests my password with a pop-up instead of a terminal window, but doing this runs the whole script with sudo, which is a problem, because TeamViewer refuses to start with sudo. How can I solve this?


I recently did a clean install of Windows 10, overwriting Ubuntu. How did Windows find out that I had activated Windows 10 before on my computer? It didn't ask me for a product key, but it is activated.


I asked similarly before, but I really have to do this soon. Please help me. ı have signals that are received from sensors (seismometers) are usually noisy and of very small amplitudee. The frequency range of these signals varies between 0.01 and 1000 Hz.A high-gain band-limited amplifier is needed. 1)The amplifier should be able to provide a dynamic range of over 60 dB. 2)Maximum output voltage is 10 V p-p 3)The amplifier bandwidth should be limited to 1-200 Hz, such that high-frequency noise is blocked. Low-frequency noise (1-200 Hz) usually has amplitude of up to 100 nV p-p, with input impedance of 4 k ohm.  I can't decide which type of transistor to use.at the same time I could not adjust the gain and bandwidth of the transistor please help


Why wouldn't the `which` command work for `cd`? I can't find the executable for `cd` either!

I tried which cd and it didn't give a path but instead returned the exit code 1 (checked with echo $?). The coreutil cd itself is working, so the executable should be there, right? I also ran a find for cd, but there was no executable file shown. How is it implemented then?  Update:  I don't know if I should ask this in another post but since I think it is good here, I'm expanding (?) the post... So the answer was actually quite simple, there's no executable for that — because it's a builtin — But I've found some builtins (bash shell in Fedora) have the executable files! So builtin -> no executable isn't right I suppose? Maybe an answer explaining what builtins actually are (builtin commands?), which actually is the matter here, rather than focusing more on cd... Some good links posted previously indicate that builtins are not programs... so what are they? How do they work? Are they just functions or threads of the shell?


Move file to another user's home directory (without sudo)?

I have a couple of files that I want to move to another's user home directory. I don't have permissions to write to that user's home directory, but I know his password.  I know how to copy the file using scp (see ). However, if I want to move the file, copying and then removing the original file is inefficient. Is there a way to move the file, without using sudo (I don't know the root's password)?


Paying off with cash or paying off through interest income

I was wondering if I have some cash in-hand which pays me an interest component that can pay off the home in 8 years, I invest in a property in country like India where I get 6% (at least as of today) as rate of return per year, is it smart to fixed deposit the money and pay mortgage through interest income?  Worst case I have the money as FD and I can pay off the loan in total by breaking the FD. I do understand that it is stupid to pay interest for the loan I am taking for buying the property, but heck with it if I lose one more year or may be 2 years worth of interest income from the fixed deposit. I do not have to pay a penny from my pocket and the property gets paid by the interest from FD deposit right?   Is there something off that you see with this approach?


Do electrons jump from terminal-to-terminal in the vacuum of space?

With enough voltage, electrons can jump 'thin air' to a negative terminal or ground here in Earth's atmosphere; an example is the Tesla Coil's ability to transfer electricity without the use of a physical connection.  Consider a battery with two wires in the vacuum of outer space. With enough voltage to bolt from the positive output to the negative wire at the correct distance, would the bolt occur?  Response to 'sammy gerbil's comment: To my current understanding (which may be incorrect), the electrons use the air particles in between the terminals as a path of travel to reach negative/ground. Being the vacuum of space such particles would be non existent so I assume the bolt would not occur. However the concept intrigued me and not being 100% certain with my own resolution, I took the question here.


Optimizing $(X_{n}+c)^{2}$ to show that $P(\overline{X}_{n}\geq \lambda) \leq E(X_{n}^{2})/(EX_{n}^{2}+ \lambda^{2})$

Define $\overline{X}_{n}:=\max\limits_{1\leq m \leq n} X_{m}$ and let $(X_{n})_{n}$ be a martingale where $X_{0}:=0$ and $EX_{n}^{2}< \infty$  Show that $P(\overline{X}_{n}\geq \lambda) \leq E(X_{n}^{2})/(EX_{n}^{2}+ \lambda^{2})$  As a hint: Consider $(X_{n}+c)^{2}$ and optimize over $c$.  It is clear that $((X_{n}+c)^{2})_{n}$ is a submartingale and when I optimize over $c$, I get:   $X_{n}^{2}+2X_{n}c +c^{2}\Rightarrow 0=2X_{n}+2c=0\Rightarrow -X_{n}=c$  It is also clear I need to use Doob's inequality but I am not sure how to go about this, and how the above optimization helps me.


Is there any workaround to use if statement in troposphere templates?

I'm trying to add an if statement in add_resource of troposphere, but I can't. Is there any workaround to do so? s3_bucket = t.add_resource(Bucket(     "MyBucket",     if 2>1:        BucketName="bucket1",     else:        BucketName="bucket2",     CorsConfiguration=CorsConfiguration(         "CorsConfiguration",         CorsRules=[CorsRules(             "AllowOrganization",             AllowedMethods=["GET"],             AllowedOrigins=["*"],         )]     ),     Tags=Tags(         Environment="aa",     ) ))  Edit: I tried to use ternary operators as well, but it didn't work. BucketName= if 2 > 1: "bucket2" else: "bucket3",


Does Ubuntu have a MS Office equivalent?

Microsoft has multiple apps like Word, Excel and PowerPoint. Google has their versions of them, such as Docs, Sheets and Slides. I saw there's LibreOffice that's similar to MS Office, but I also wanna know if Ubuntu has their own. Is there a similar form of MS Office from Ubuntu?


Is there any trick to evaluate this or this is an approximation, I mean I am not allowed to use calculator.     $$\sqrt{7\sqrt{7\sqrt{7\sqrt{7\sqrt{7\cdots}}}}}$$


VirtualBox: Ubuntu instance fails to start with error

I get the below error when trying to start up my Ubuntu instance on VB in my Windows 10 env.  VMMR0_DO_NEM_INIT_VM failed: VERR_NEM_MISSING_KERNEL_API_2 (VERR_NEM_MISSING_KERNEL_API_2). VT-x is not available (VERR_VMX_NO_VMX).  Result Code: E_FAIL (0x80004005) Component: ConsoleWrap Interface: IConsole {872da645-4a9b-1727-bee2-5585105b9eed}  From googling, ive turned off Virtualisation in my laptop but still get this error, any tips?


Proof that eigenvectors corresponding to different eigenvalues are linearly independent.


I try to fetch a Wikipedia article with Python's urllib:  f = urllib.urlopen("http://en.wikipedia.org/w/index.php?title=Albert_Einstein&printable=yes")            s = f.read() f.close()   However instead of the html page I get the following response: Error - Wikimedia Foundation:  Request: GET http://en.wikipedia.org/w/index.php?title=Albert_Einstein&printable=yes, from 192.35.17.11 via knsq1.knams.wikimedia.org (squid/2.6.STABLE21) to () Error: ERR_ACCESS_DENIED, errno [No Error] at Tue, 23 Sep 2008 09:09:08 GMT    Wikipedia seems to block request which are not from a standard browser.  Anybody know how to work around this?


I am having some problems trying to translate this to nginx, today I can't make my brain to work well and solve this!  RewriteEngine on  RewriteCond %{REQUEST_FILENAME} -f RewriteRule ^(.*)$   $1                 [L]  RewriteRule ^(.*)$   index.php?url=$1   [QSA,L]


How do I make it my primary OS 16.04 LTS Ubuntu

So I downloaded Ubuntu as a dual boot but I now change my mind and would like  to delete the dual boot and install it as my primary OS how would I go about doing that?


Do users really have to be committed to proposals to post in the private beta?

The  proposal just recently entered private beta. Supposedly, . However, I tried posting on Tezos using  on which I hadn't committed to the proposal, yet I was still able to post an answer! (check  if you don't believe the account wasn't committed)    Is this intentional and there has been some change to allow non-committed users to participate in the private beta, or is this a bug?


I heard median of any number of data. Suppose we have a data      [13,23,23,23,54] The median of this data is is 23. How we calculate the weighted median of same data (as mentioned above).  **  (this is i get when i Google it. But things are not clear).


A Java collection of value pairs? (tuples?)

I like how Java has a Map where you can define the types of each entry in the map, for example <String, Integer>.   What I'm looking for is a type of collection where each element in the collection is a pair of values.  Each value in the pair can have its own type (like the String and Integer example above), which is defined at declaration time.    The collection will maintain its given order and will not treat one of the values as a unique key (as in a map).    Essentially I want to be able to define an ARRAY of type <String,Integer> or any other 2 types.    I realize that I can make a class with nothing but the 2 variables in it, but that seems overly verbose.    I also realize that I could use a 2D array, but because of the different types I need to use, I'd have to make them arrays of OBJECT, and then I'd have to cast all the time.    I only need to store pairs in the collection, so I only need two values per entry.  Does something like this exist without going the class route?  Thanks!


Decimals in table don't align with dcolumn when bolded

I am making a table using booktabs and dcolumn. It works perfectly until I tried to bold one of the numbers and then the decimals won't read properly.  Are there any workaround here?  \documentclass{article} \usepackage{booktabs,dcolumn} \begin{document} \newcolumntype{.}{D{.}{.}{-1}} \begin{tabular}{l .} \toprule M & \multicolumn{1}{c}{N} \\ \midrule 5 & 12.0 \\ 10 & \textbf{24.0}\\ \bottomrule \end{tabular} \end{document}


Would like to have each line in a file repeated a fixed number of times.  e.g. have each line repeated four times:  a b c   becomes:  a a a a b b b b c c c c   I've done some searching, and there are a lot of questions and answers along the lines of doing the reverse, e.g. merging duplicate lines into single lines, and maybe a few about doubling lines by printing them again.  It would be easy to do this in C, but I wish I knew more about the native commands so I wouldn't have to resort to these kinds of one-off throw-aways all the time.


will two entangled particles still remain entangled if one of the pair if sent inside of a black hole?

Imagine that i had two entangled photons . I kept a photon beside me without knowing its spin and sent the other photon inside a black hole . Then i measure the spin of the photon beside me . Is is certain that the photon inside the black hole will have opposite spin as the one beside me?


How long is too long to leave the shutter open before prolonged exposure to light damages the sensor?

I'm about to start exploring the world of long exposure shots, using my Canon EOS M. The camera has a standard max exposure time of 30 seconds, but in bulb mode I can keep the shutter open indefinitely (using a wireless remote to control the shutter.)  How long can I leave the shutter open without running the risk of prolonged exposure to light damaging my sensor?  For the purposes of this question assume I'm shooting in summer daylight, so that we can go by the worst case.


I remember seeing somewhere that if you breed a Pokemon from a different region its offspring would have a higher chance of being shiny. Is this true?  What other methods can be used to increase the odds of obtaining shiny Pokemon?  Also, What is the chance of breeding a shiny if one/both of the parent Pokemon are also shiny?


Spectrum of unbounded Operators + Spectral Theorem

I've seen a variaty of slightly different definitions for the spectrum and its division into pure point spectrum residual spectrum and so on. Thus I'm wondering what could be an appropriate definition.  Moreover, when does the spectral theorem apply in principle? I have heard for normal operators and read once (I don't remember where) positive operators I guess...


So, I am having trouble approaching this question:      Prove that for all natural numbers $n > 2$, there exists a prime number $p$ such that $n < p < n!$    I have been thinking about Bertrand's postulate for some time; however, that theorem cannot be taken as a given in this question. So, I have to actually prove Bertrand's postulate first, before continuing towards the actual claim in the question.   Note: Direct proof, proof by induction, contraposition, exhaustion (cases), contradiction, etc. all ideas and contributions are welcome.


How do you make minecraft run smoother and get more FPS?

I have a HP Envy All in One, running Windows 8 I believe. I use mods such as optifine, potion counter, direction hud and togglesneak. Anyways, whenever I'm running around regularly, I get around 60 fps, whenever I start to PvP, it drops down to around 30 to 40. Anyways, how could I end . up getting more FPS? Would I need to upgrade anything? Need to get a new PC (because I'm most likely buying one soon anyways) Just let me know, thanks.


I'm trying to animate a mesh with different eye textures but it's not working.     This is a texture made by me to animate but I still couldn't figure out how to do it. I've seen tutorials on the internet but they don't work to me.


I wonder if "owed" and "due" mean the opposite in the following quote from ?  In banking and accountancy, the outstanding balance is the amount of money owed, (or due), that remains in a deposit account (or a loan account) at a given date, after all past remittances, payments and withdrawal have been accounted for. It can be positive (then, in the balance sheet of a firm, it is an asset) or negative (a liability).  I think  owed and due both mean someone owes someone else another something. But in the quote, it looks like owed means someone else owes someone something, and due means someone owes someone else something. I am confused. Thanks!


Can I use different initialization vectors (IV) for the same data in AES-CBC?

Every time I encrypt the data, I generate a different IV. Suppose the attacker has access to all files ever encrypted. They don't know the key, but they do know the IV. The problems is: if I save the same data with the same key several times, I generate different encrypted data. Theoretically, this could give the attacker some information about the key or the data, assuming they know that neither have changed. Should I worry about this?  This is mostly a theoretical question. In practice I could simply check if the data or the key have changed. If not, then I don't change the encrypted data.


Should I ask my teacher before using speech-to-text software?

Should I ask my teacher before using software of speech-to-text in classes ? The software in question does not record (the audio) at all, just "hear" the input and output text.   What about using it in conferences and lectures ? And is it OK to share this with other students ? I'm more worried about legal issues than anything else (European Union and U.S jurisdictions).


How to mount electronics on a vehicle chassis safely

I want to implement a control system I designed for a light electric motorbike. I would like to mount it as professionally as possible on the chassis. It consists of a power system pcb and a SAMC21 development board which I'll merge later once this all works properly. I have tried screwing it directly on the aluminium chassis but have found that shocks and vibrations from the horn disturbed the system or even destroyed it upon large shocks like a few hammer hits. Is there a specific way car and motorcycle manufacturers mount their electronics to make their system as robust as possible? Thank you for your help!


Which one is correct: 'The first two quarters of current financial year' Or 'The first two quarters of the current financial year'


What movie has aliens hunt people using living tentacled discs?

I saw a movie in the 80's where aliens were hunting people — from what I remember in the woods, or a real rural area — and they would throw these living disc-like creatures with small tentacles on them at the humans.  What movie was this?


Permission to make symbolic links in Windows 7?

How can I grant a particular user the permission to create symlinks in Windows 7?  I've searched through "Group Policy" and Google, but haven't found anything.  On a side note, is there a way to search through everything in Group Policy Editor? The filters only seem to work on particular subtrees. I never actually found anything using the filters.


Can i have 2 different gpus from only Nvidia or AMD

Can i have, for exampe RTX 3060TI for gaming and a gt 1030/210 for a second one, for google and other small tasks? *if i use amd processor


How to split the terminal into more than one "view"?

From vi, if you issue the command :sp, the screen splits into two "views", allowing you to edit more than one file from the same terminal.   Along those same lines, is there a way to have multiple shells open in the same terminal?


Proving an invertible matrix which is its own inverse has determinant $1$ or $-1$

Let A be an invertible $n \times n$ matrix whose inverse is itself. Prove that $\det(A)$ is either $1$ or $-1$.    I'm really lost in class. I don't even know where to start. Please help.


Appending to an array attribute of an array of instances

Lets say I have the following class:  class test(object):     def __init__(self):         self.arr = [0]*10   And then I use it as:  arrOfTests = [test()]*10 arrOfTests[0].arr.insert(0,1) print arrOfTests[0].arr[0] print arrOfTests[1].arr[0]   Which returns  1 1   Why is arr[0] of attOfTests[1] (and also all the others) 1 as well? By all my best effort, I could not figure this out.. Thank you in advance!


What three odd integers have a sum of 30?

I've been asked the following question:  What three odd integers from the set {1,3,5,7,9,11,13,15} that when summed together equals to 30? Note that any integer can be used more than once.  Is there any possibility to solve these kind of questions with some formulae? Note I have gone through the answers for making it with 5 numbers.


Derivation of the censoring likelihood function?

The (right-) censoring of likelihood function is defined as:  $$     L(\theta) = \prod_{i=1}^m f(x_i;\theta) \cdot \prod_{i=m+1}^n P_{\theta}(X_j>a) $$  where observations $x_i$, $i=1,...,m$ have known values and for $m+1,...,n$ the values are unknown.  I would like to know, how has this been derived? I.e. why is this the definition for censoring?


In one of the labs for learning Linux system administrator I have to do :   Now change the value by modifying /etc/sysctl.conf and force the system to activate this setting file without a reboot. Check that this worked properly.   here is what i must do:     Add the following line to /etc/sysctl.conf:  net.ipv4.icmp_echo_ignore_all=1       and then do:  $ sysctl -p    how to do this and with which text editor?


How can I customize different nodepart with different textures?

My question is how can I customize hatch patterns(grid, vertical line, etc.) for different nodepart in a node?  The following is a failed try.  \documentclass[border=2mm,convert]{standalone} \usepackage{tikz} \usetikzlibrary{shapes.multipart,patterns}  \begin{document} \begin{tikzpicture} \node[rectangle split,rectangle split parts =2,rectangle split part fill={red!30,red!10}, rectangle split part pattern={grid,},draw]{one \nodepart{second}two}; \end{tikzpicture} \end{document}


Single word (Preferably) for phenomenon when two persons who are at not good terms with each other and involve third person to correspond between them

What is it called (Preferably single word) for phenomenon that is taking place when three parties are involved such that first two persons (Group of people, party or Departments, etc) are at not good terms with each other. And so first party involves you (or your department) as the third person to talk (Converse, correspond) to the second party and vice versa. The question is about what kind of phenomenon is happening between all the three parties and not what the third party party is doing individualistically. The point of this is to highlight to the management the amount of work that the third party (its department or members of its group) have to undertake is a overburdening our department (third party). Example: ________ is causing excessive work burnout, disgruntlement, disengagement in our department (within third party) since the XYZ department (first party) is reluctant to correspond with ABC department (Second party) and vice versa. And we (third party) have to pay the price.


Check if a file is a plain text file or binary files in python

I have a task that need to list all the plain text files in a folder that contains plain text files and binary files, without knowing the file extension. I have been doing lots of google search but still not able to find the answer. any hints ? Thanks.


Is there some way to decrease folders/icons size in Nautilus 3.18?

In the newest Nautilus 3.18 the smallest folder/icon size is really too big. Is there some way to hack (or something) this program and set a smaller one?


I have looked around and cannot find the answer so I ask here. It is well known that if $R$ is noetherian then $R[X]$ is too, but what about the converse? If $R[X]$ is noetherian can we say $R$ is? My gut feeling says no and the fact it seems so hard to find an answer makes me feel certain about it.


prove that if $\lim\limits_{n\to\infty}(a_{n+1}-a_{n})$ exist then $\lim\limits_{n\to\infty}\frac{a_{n}}{n}=\lim\limits_{n\to\infty}(a_{n+1}-a_{n})$ So that's what I did so far  Let $$B_{n}=\frac{(a_{2}-a_{1})+(a_{3}-a_{2})+...+(a_{n+1}-a_{n})}{n}=\frac{(a_{n+1}-a_{n})}{n}$$ and we know that if$\ \lim\limits_{n\to\infty}(a_{n+1}-a_{n})$ exist that's mean that $\lim\limits_{n\to\infty}B_{n}=\lim\limits_{n\to\infty}(a_{n+1}-a_{n})$ Thus we have $\lim\limits_{n\to\infty}\frac{(a_{n+1}-a_{n})}{n}=\lim\limits_{n\to\infty}(a_{n+1}-a_{n})$ But I don't know how to go from here


Composition of Functors which have adjoints has also an adjoint

The exercise is the following: Suppose $F$ has right adjoint $G$ and $H$ has right adjoint $J$ ($F:\mathbb{A}\rightarrow\mathbb{B}$ and $H:\mathbb{B}\rightarrow\mathbb{C}$ with $\mathbb{A,B,C}$ categories). Prove that $GJ$ is the right adjoint of $HF$.   What is the best way to start with? I want to do this by the two-way-rule, thus by bijective correspondence, but i don't see how to start. Someone who can help me?  Thank you very much.


Is there a Python command that will allow me to set the camera clip end for viewing my objects in Blender (via scripting)? According to  the "bpy.context.space_data" variable is read-only.


Why is momentum conserved when a ball hits a vertical wall?

Almost in every book on physics, there's an example of conservation of momentum when the ball that is moving horizontally in the air, hits some massive wall. They claim that the return speed of the ball when it bounces off is the same as it was before the hit. If there were no external forces acting on the system (or their net force was zero) that would be fine. But in this case, there is a gravitational force acting on the ball, and because there is no surface underneath it, there's no normal force and therefore it doesn't "cancel out" the gravitational force. So my question is, why they say that the momentum conserved? Do they neglect the gravitational force or what? I'm quite confused.


What is the "+1 rule" for Adventurers League?

This Q&A refers to a rule that was in use for AL from 2015-2020. See . This Q&A has therefore been locked against new interactions. Always check your campaign documentation for applicable options and rules.  In many places I see referenced a "+1 rule" for characters legal in Adventurer's League play. What does this mean?


Independence and conditional independence between random variables

For a family of random variables, I was wondering if independence and conditional independence under any condition among them imply each other?   If not, can these two concepts imply one another under some special cases?


I keep getting a null point exception in here and I don't know what's wrong with my code. I'm having Constructor that parses a String s like { x=-1 y=-2.0 z=3d } into the internal HashMap representation of the Vector(_hmVar2Value).  public Vector(String s) {     String[] splitString = s.split(" ");     for (int i=0;i<splitString.length-2;i++) {         String[] str=splitString[i+1].split("=");         double x = Double.parseDouble(str[1]);         _hmVar2Value.put(str[0],x);     } }


I've recently been using my iPad with TexPad to do a lot of tex work.  One thing that I do not know how to deal with is the issue of animations on the iPad, as my current method for embedding animations (usually mp4's) in the document is to use the media9 package which accomplishes this with flash.  Since iOS does not support flash, none of the standard PDF readers, including Acrobat, are capable of displaying the animation.  I was wondering if anyone had a strategy for putting animation in beamer in a way that the iPad can render it?  Note, I am really asking for alternatives to using a flash based solution entirely, rather than just querying how to run flash content on iOS.  I am open to using image sequences, other media formats, etc.


Time ordering operator if commutator is $c$-number function

I have a question concerning the time ordering operator. Let's suppose we have a time evolution generated by some Hamiltonian $H(t)$ given by $$ U(t)=T_\leftarrow\exp\left(-\mathrm{i}\int_0^t\mathrm{d}s\,H(s)\right)\tag{1}. $$ In Breuer and Petruccione, it's said that if the commutator of the Hamiltonian at some time $t$ with itself at some other time $t^\prime$ is a $c$-number function/ a complex function, i.e. $$\left[H(t),\,H(t^\prime)\right]=f(t,t'),$$ then the time evolution is given by $$ U(t)=\exp\left(-\frac{1}{2}\int_0^t\mathrm{d}s\int_0^t\mathrm{d}s^\prime\,\left[H(s),\,H(s^\prime)\right]\Theta(s-s^\prime)\right)$$ $$\times \exp\left(-\mathrm{i}\int_0^t\mathrm{ds}\,H(s)\right),\tag{2} $$ where $\Theta(s-s^\prime)$ is the Heaviside function. No proof or reference is given and I could not find any explanation anywhere, this is why I ask here. Any help would be very appreciated.


Is ${\bf x^TAx} \ge { a \bf x^Tx}$ for some $a>0$ not dependent on $\bf x$ if $\bf A$ is positive definite matrix?

Is there a theorem saying ${\bf x^TAx} \ge { a \bf x^Tx}$ for some $a>0$ not dependent on $\bf x$ if $\bf A$ is positive definite matrix? If there is, can some help provide a reference or some explanation? Thank you!


I use Texstudio and Miktex on Win 7 as a portable version.  Today i updated my miktex-packages and everything worked fine except the "\usepackage{tikz}" command.  I made a fresh reinstall with the newest versions of miktex and texstudio, opened my latex-document and compiled it. Miktex installed all missing packages on-the-fly except pgf/tikz, wich gave an error instead. I installed it manually in the package manager but texstudio still says "File "tikz.sty" not found".  Unfortunately I have to use the portable version, because I don't have any admin rights. The last time I worked on that document, everything worked fine.  Any ideas?


Create answer from comment when there are no answers

Recently I've seen a couple of questions (across various SE sites) that I could answer, upon reading the question & comments I've found that it's been answered as a comment but there's no actual answer.  Is it ok for me to provide an answer that mostly consists of some-one else's comment? (I'd try to improve on the comment by expanding on it or providing examples, give attribution to the original commenter & wait a few days before doing so.)  I dislike the idea of "stealing" someone else's rep, but I also feel every good question should have an answer (ideally accepted), since this improves the question for future users.  Are there any rules/recommended practices for doing this, or should I even be doing this?


I have an object of class and want to re initialize the object by a function So I am writing a discord bot and there's one object that i want to be recreated every time the bot gets a command. import discord client = discord.Client() obJ_class = bot_friendly.Exec() # this creates the object and everything works fine   now @client.event async def on_message(message):     if message.content.startswith("&&exit"):     await message.channel.send("Exiting")     await client.close()     print("Successfully logged out")     if message.content.startswith("&&update"):     await message.channel.send("Wait a few seconds")     obJ_class = bot_friendly.Exec()  here the error is Shadows name 'obJ_class' from outer scope I would like to know if this is even doable or should i just make another function that does what the __init__(self): does but just name it update():


I would like to prove the following inequality, for $n=0,1,2,...$,   $$ \binom{2n}{n}\leq 4^n.$$ I already proved it by induction, and I'm looking for another proof.


One way ticket to Seoul with Canadian Passport?

I am planning on just traveling to many different places, I know that I'm allowed to stay in certain places for as long as 3 months, but would they allow me to stay in Seoul for 3 months, without a flight returning home?   The thing is that I'm not sure if I will be going straight back to Canada (most likely not) after my visit in Korea or continue onwards to other places.


Which folder is recycle bin in on Win7? How to check files there?

I was using another account before. Let me call it account A. And I deleted a lot of files to the Recycle Bin at that time. But before I removed account A I forgot to empty the Recycle Bin.   My question is, are my files still there? I've searched and found that the Recycle Bin may live in $Recycle.Bin, but I can't open files there so I can't know what they are. Any help how to open deleted files or how to delete them permanently?


Single line code is hidden by the horizontal scrollBar

The horizontal ScrollBar on a one line code on any post is hiding the code for me.  I'm using Google Chrome 71.0.3578.98 on  (Mojave), but I think this bug is a general issue. And here are some examples:  1- First example: once you use the horizontal scrollbar, it will hide the line of code.  >>> code simple code lorum ipsum code simple code lorum ipsum code simple code lorum ipsum ; # just some code   2- Second Example, an image from another Stack Exchange site    I hope this simple bug will be fixed and thanks.


Let $\sum_{n=1}^\infty x_n$ be convergent and $\sum_{n=1}^\infty y_n$ absolutely convergent. Is it true that $\sum_{n=1}^\infty x_ny_n$ converges?

Let $\sum_{n=0}^\infty x_n$ be convergent and $\sum_{n=0}^\infty y_n$ absolutely convergent. Is it true that $\sum_{n=0}^\infty x_ny_n$ converges?


Update to 20.04: Missing icons and icon alignments

I've just updated my system to Ubuntu 20.04. I'm facing issues with missing icons and alignment of icons in the top bar. I've attached screenshots below.   Misaligned Icons:   Missing Icons:


How do I print all my results on one line with the spaces

My code takes a line of text from the user and attempts to encode or decode the text using a function I have created. However I am trying to print all the results of one line and also include the spaces that the user inputted so that it clearly shows that each word has been encoded. It currently just prints all the results underneath one another and does not include the spaces that the user inputted.   print ""  # To God be the Glory  text = raw_input("Please enter a line of text: ") text = text.lower()  print "" key = int(input("Please enter a key: "))  def ascii_func (text) :  for charc in text:     if charc in ['-', '+', '*', '/', '!' , "@"]:         print "Error input is not correct"  for charc in text:      if charc != " " :        charc = ord(charc)        charc = (charc - 97) + key        charc = (charc % 26)        charc = charc + 97        charc = chr(charc)        print charc  ascii_func(text)


Normalize parameter in sklearn Ridge, Lasso, ElasticNet

Is there any risk or disadvantage to set normalize=True when using ridge, lasso or elasticnet or does it only have benefits? And what is the impact on the range of alpha if it is set to True, does it even make sense to have variables in different units and apply those models without normalizing them? Thanks for clarification!


Command works in terminal but not in bash script

If I want to delete everything in the current directory except for "myfile", I can use  rm -r !("myfile")   But if I put this in a script (called cleanup):  #!/bin/bash rm -r !("myfile")   I get:  pi@raspberrypi:~/tmp $ ./cleanup ./cleanup: line 2: syntax error near unexpected token `(' ./cleanup: line 2: `rm -r !("file2")'   If I run   ps -p $$   I can see that my terminal is using bash,   PID TTY          TIME CMD 1345 pts/3    00:00:02 bash   so I'm unclear on what the problem is.    Notes:   I realize that if the script actually worked, it would delete itself. So, my script really would be something more like: rm -r !("cleanup"|"myfile"), but the error message is the same either way.  As shown by the blockquote, this is on a Raspbian OS (9 - stretch), which is Debian based. I feel like this question is bound to be a duplicate, but I can't find it. There is a similarly named , but it is in regards to inheriting variables, and so doesn't address my issue.


My Minecraft Server is running perfectly and I can connect. But, if others try, it says "Can't connect: connection refused: connect".  I have a Mac, with 8GB RAM and am using Rcon. I connect using localhost. I can't even connect with telnet!


How does the inhibitor chip execute Order 66?

The inhibitor chip ensures that Clone Troopers of the GAR will unquestioningly execute Order 66 when it is given, denying them free will in that crucial moment. How does it do it though? More specifically, does the chip execute its function via temporary mind control or a permanent change to their brains?  The implications are that, for the former, the clones will eventually regain full control of themselves, thereafter realising what they have done and will most probably regret their actions since, in such a case, the Jedi's trust in their loyalty are not unfounded in a sense. For the latter, I feel that there may be various ways it is achieved. The chip may either permanently override the clone's brain, taking control for life, or it may reconfigure the clone's brain altogether, such that while the clone is still in full control of himself, he is literally no longer the same person he was prior to the Order.  As such, how the inhibitor chip executes its intended functionality affects the nature of the chip's design and how it is implemented.


Proving order of certain elements in a group is the same

I have an exercise which involves groups. It's probably common, but I don't know how to solve it. It sounds like this:      Let (G, $\cdot$) be a group and x, y $\in$ G. Show that ord(xy) = ord(yx).   where ord(x) is the order of x. I just tried to write $xy\cdot xy \cdot \space ...\space\cdot xy = x \cdot (yx) \cdot (yx) \cdot\space ...\space \cdot (yx) \cdot y$, letting x and y outwards. I don't know if this is a good step and I don't know how to continue. I would be glad if someone could help me.


$\lim_{x\to 0}\frac{\tan3x}{\sin2x}$= $\lim_{x\to 0}\frac{\frac{\sin(3x)}{\cos(3x)}}{\sin2x}=\lim_{x\to 0}\frac{\sin3x}{1}\cdot\frac{1}{\cos(3x)}\cdot\frac{1}{\sin(2x)}$  From this point I am lost. I believe I can pull a 3 and 2 out but I am not sure how. Can someone give me detailed instructions for a person in Calculus 1?


Up-voted question with down-voted answers not listed as "Unanswered"

has 15 up-votes and no up-voted answers. If one selects "Unanswered" from the top banner, it is not listed as an unanswered question.    This is the case for all questions with up-votes but down-voted answers, and seems like a very bad idea: getting a down-voted answer should not cause a question to be considered answered.    This is also contrary to the documented behavior described in prior questions:           In comments, it is claimed that this behavior is intended.  If this is the case, then the bug is the description of the top-level "Unanswered" page, which currently says:     questions with no upvoted or accepted answers   but should instead say something like     questions with no upvoted or accepted answer and no downvoted answers


Looking for a science fiction short story called "The Pacer"

The story I read back in the mid-late 70's was in a two or three-parter in Christian magazine, but the story itself did not have religious themes, per se.  The main story was about a group of space academy cadets in a ship.  Our hero is an idealistic man and his best friend, both who are cadets on the ship.  What's also common knowledge is that one of the cadets is a "pacer" ... a cyborg who is placed there to maintain the high competitive edge and push the the real cadets to be their very best.  And it's a common belief amongst the cadets each year, that you must find and kill the cyborg or your class is cursed.  Something goes wrong and the ship's computer loses it's ability to pilot the ship.  The commandant asks for a volunteer to help with the navigational computations.  Everybody knows that it's very likely going to be the pacer who volunteers.  So our hero's best friend steps forward and the rest of the story is about the other cadets encouraging him to do some snooping, get proof his friend is the pacer, and then help kill him.  The hero is torn.  ... on the other hand, maybe there ARE religious themes  lol!  Anyway, I'd love to know the author so I can track down this story and read it again.  Thanks all !


Further to , I have .nc and .asc files of crop area and production for maize, rice and wheat. , about QGIS importing .asc files:     QGIS has native support for this format.   ESRI grid (.asc) files can   be directly opened in QGIS by selecting Layers >>> Add Raster Layer.    The .asc file can also be dragged and dropped into the QGIS session, rather than using the Add Raster Layer option.   But when I do either, I get this error:      .asc is not a supported raster data source.     which has been reported at    I am using version 2.0.1-Dufour.


If you have an electric charge somewhere and you make a new  electric charge right now when do these electric charges start to interact with each other? is it immediately or it take some time ? how much time does it take?


I lost data while changing os from windows to ubuntu 18.04

I lost data while changing OS from windows 7 to Ubuntu 18.04.How can I recover my data from partitions in Ubuntu?


Is it safe to upgrade from Ubuntu 16.10 to 17.04?

I became a linux user with 16.10, about 4 months ago. I'm loving it, but since the final version of 17.04 is about to come out, I'd like to upgrade. Is there any benefit to a clean install? I don't really want to have to reinstall, but if there's anything, anything, that would give me a reason to clean install, I'll do it. I prefer to go on the safe road. Also, how do I update? With update-manager -d and following the instructions, with sudo apt dist-upgrade, or with sudo do-release-upgrade?


If $P(x)$ is any polynomial of degree less than $n$, show that $\sum_{j=0}^n (-1)^j\binom{n}{j}P(j)=0$.

If $P(x)$ is any polynomial of degree less than $n$, then prove that $$\sum_{j=0}^n (-1)^j\binom{n}{j}P(j)=0$$  My approach was to try and prove this separately for $j^k\ \ \forall\ \ k<n$, instead of $P(j)$, since $P(x)$ can be written as $a_{n-1}x^{n-1}+a_{n-2}x^{n-2}+...+a_0$. However, I could not get anywhere.It would be much appreciated if someone could provide a rigorous solution for this or any key insights.Thanks a lot


Both sides differentiation expression with integral

I have a problem with derivation of some function. This is related to computing the Poincare Map of Logistic Population model with Periodic harvesting. This function is:  $\phi(t,x_0) = x_0 + \int_{0}^{t} f(s,\phi(s,x_0)) ds $,  where $\phi(t,x_0)$ is a function: $\mathbb{R}  \times \mathbb{R} \rightarrow \mathbb{R}$.  I'm trying to differentiate  equation of this function both sides  with respect to $x_{0}$. In book from this equation comes from the result of this differentiation is:  $\frac{\partial \phi}{\partial x_0} (t,x_0) = 1 + \int_0^{t} \frac{\partial f}{\partial x_0} (s, \phi(s,x_0)) \cdot \frac{\partial \phi}{\partial x_0} (s, x_0)ds$.  I can't understand expression under the integral. In this book it is explained that it is clear from chain rule.Could someone explain to me this transformation in easy way? I will be grateful for your help Best regards


How rel="next" and rel="prev" helps in SEO if used for pagination?

How rel="next" and rel="prev" helps in SEO, if used for pagination? Is it really required ?  i.e. imagine you're on page 2:  <link rel="prev" href="http://www.example.com/article-part1.html"> <link rel="next" href="http://www.example.com/article-part3.html">


What does mean of "return (int, int);" in c language?

I am found below example and I can't understand the calculation of the return statement (return (kk, ll);).  Is there anybody who explain to me about the calculation of the return statement?  #include<stdio.h>  int addmult(int ii, int jj) {     int kk, ll;     kk = ii + jj;     ll = ii * jj;     return (kk, ll); }  int main() {     int i=3, j=4, k, l;     k = addmult(i, j);     l = addmult(i, j);     printf("%d %d\n", k, l);     return 0; }


Proving the equivalence of a complex polynomial and a strange series.

I have a homework question:   Let $f(z) = 1 + z + 2z^2 + 3z^3 + 5z^4 + 8z^5 + 13z^6 + ...$.   (a): Show that $f(z) = \frac{1}{1-z-z^2}$ for all z in the disk  $\{z: |z| < R\}$ for some number R.   (b): Find the value of R in part (a).  My professor gave us a hint: show that $f$ satisfies the equation $f(z) = 1 + zf(z)+ z^2f(z)$.  I know that the series is something like $\sum_{n=0}^{\infty} c_n z^n$ where $c_n$ is the nth Fibonacci number, but I don't know how to approach showing equivalence.  I don't think that I understand how his hint helps us. I feel like it should be my jumping off point for this problem, but I don't see how it helps me at all.


Can someone please give me a hint to prove that if the order of the group $|G|=6$ and $G$ is abelian, then $G$ is cyclic?  My idea: if G is of order 6, then say, $x\in G$, then $|x|=|\lt x \gt|=6$ , then $G $ is cyclic? I do not know if this is true  Thanks in advance!


Good habits: using \ensuremath to typeset math in text mode

All of this question is about \ensuremath command. I would like to know, possibly from expert users, if there are any counter effects in using math commands in the text via \ensuremath and whether comprehensibility can be affected when using too many math symbols in this way.   If there are any issues, what is the usefulness of \ensuremath command? When am I supposed to use it and what's is proper application? I mean if it was thought just to use every math commands in text mode I would \renewcommand all math mode like  \let\oldalpha\alpha \renewcommand{\alpha}{\ensuremath{\oldalpha}} %lot of \let after \renewcommand{\beta}{\ensuremath{\beta}} \renewcommand{\gamma}{\ensuremath{\gamma}} %... AND SO ON AND SO ON   so that I would have no more troubles in forgetting \(...\) or $...$ around.


Is a Wild Shape attack considered an unarmed strike?

So, I got intrigued by grappling after reading  for 5e. It didn't mention if wild shape attacks were considered unarmed strikes, especially in regards to the Tavern Brawler feat's last bullet, which enables a grapple attempt after hitting with an unarmed strike.  It doesn't say in the PHB under the Druid section. In the MM, it says that a beast's attacks are Melee Weapon Attacks. However, the Alter Self spell says that the claws, fangs, etc are unarmed strikes. So, are they or are they not considered unarmed strikes?


What is the mean and variance for this Normal distrbution?

Suppose, we have $X_1,X_2,$ and $X_3$ i.i.d random variables (RV's) from $N(\mu,\sigma^2)$. Let $Y=\frac{X_1-X_2}{2}$, and $W=X_3-Y$. Then is $W\sim N(0,2\sigma^2)$ or $W\sim N(0,\sigma^2)$?


Find out which program is starting and stopping within a second

On my laptop, about every half hour, a window pops up and closes again very quickly.  I think it is a program that starts and stops really fast. I want to know which program that is.  Is there a way to find out which program is starting and stopping?  Already looked in the task scheduler, registry run and run once but did not find anything.  Also looked in the event viewer, but cannot find anything or I'm searching in the wrong place.


What is the "object" of a group (when viewed as a category) analogous to in a group (when viewed as a group)?

From MacLane's Category Theory:  A group is a category with one object in which every arrow has a two-sided inverse under composition.  So the analogies I see between a category group $CG$ and a group $G$ is as follows:  Arrows : Elements of the group Identity arrow : identity element composition of arrows : group operation Associativity function : associative group operation Unit law : identity properties All composable arrows exist : closure of the group  But the one I can't seem to understand is: What is analog for the single object in $CG$?  Single object in category : (Something for a group)?


Why Can't I Parent My Armature to My Mesh?

I've tried selecting my mesh, then my armature (correct order) and hitting Ctrl+P, and selecting "With Automatic Weights", and in the content panel it moved my mesh under the armature. But it gave me an orange message with "Bone Heat Weighting: Failed to find solution for one or more bones", and the mesh didn't deform with the bones in Pose Mode. What am I doing wrong? (I tried to add a GIF picture, but it says the recording is too large to upload.)


How can I make a silky, wispy smoke effect?

A while back, I asked a question about how to make an effect of blood in the water. No one answered, so I assume that the question was too specific. I've elected to delete that post in favour of a more general question concerning this effect.  Blender's smoke simulation seems to only give cloudy results--while I'm looking for a way to create an effect similar to these images I've found across the web:    What kind of settings would a smoke simulation require to have this?  And if it turns out that I can't make this silky, wispy, ghostly-strand effect because of limitations of the smoke simulator, is there a way I cheat and do this effect with particles and render them in a way that they appear like smoke?


Search for "similar questions" across multiple sites?

After typing the title of a question, the "similar questions" are displayed.  Is there any feature, that would provide such suggestions across all (or a configured subset of) stackexchange communities?  I came across this question, when writing a question Python postfix notation for map, filter, ...?, where I noticed, that I got only a single result with the stackexchange.com search, but many suggestions on stackoverflow.com.


AttributeError: MapDocObject: Unable to save on mxd.save/saveACopy?

I'm trying to use arcpy to save an .mxd and am having an issue.  It doesn't matter if I use mxd.save or mxd.saveACopy I get the same error.  I know it doesn't look like I am doing anything w/ it here, but it's just a portion of my code:  import arcpy import arcpy.mapping as map arcpy.env.overwriteOutput = True  env.workspace = r"C:\MGIS\FinalProject2.gdb     mxd = map.MapDocument(r"C:\MGIS\Finalproject2.mxd") df = map.ListDataFrames(mxd)[0]  for df in map.ListDataFrames(mxd): df.scale = 2000000  #Add layers into map document addLayer = map.Layer(OKXcounties) addLayer1 = map.Layer(contourLabelText) addLayer2 = map.Layer(contoursClipLyr) addLayer3 = map.Layer(clipOKXLyr) map.AddLayer(df, addLayer, "AUTO_ARRANGE") map.AddLayer(df, addLayer1, "AUTO_ARRANGE") map.AddLayer(df, addLayer2, "AUTO_ARRANGE") map.AddLayer(df, addLayer3, "AUTO_ARRANGE")  # Add contour Labels for lyr in map.ListLayers(mxd):     if lyr.name == "contourLabelText":         lyr.showLabels = True     if lyr.name == "Contour Features":         lyr.transparency = 100  mxd.saveACopy(mxd)   I get the following error:   Traceback (most recent call last):   File "C:\Python26\ArcGIS10.0\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", line 312, in RunScript     exec codeObject in __main__.__dict__   File "C:\MGIS\geog485\FinalProject2\mxdtest.py", line 7, in <module>     mxd.saveACopy(mxd)   File "C:\Program Files\ArcGIS\Desktop10.0\arcpy\arcpy\utils.py", line 181, in fn_     return fn(*args, **kw)   File "C:\Program Files\ArcGIS\Desktop10.0\arcpy\arcpy\_mapping.py", line 668, in saveACopy     self._arc_object.saveACopy(file_name) AttributeError: MapDocObject: Unable to save.  Check to make sure you have write access to the specified file and that there is enough space on the storage device to hold your document.   Space is not the issue, I have 60 GB of free space and I've checked the windows properties of the .mxd file.  Read-only box is unchecked and I've "allowed" all permissions for all groups:    Does anyone have any idea how if this is a bug or how I can fix this?  I'm using ArcInfo 10.0 SP4.


Does Stack Exchange remove Ha! from my answer?

I just began  with     Ha, I just ran into this myself!   but it would come out as     I just ran into this myself!   and an edit would not help.  Now I see how that beginning of an answer is not strictly adding to its content value, but it seems like it does not hurt and – especially with regard to the recent push for more friendliness on SE – make the user experience a bit more … natural. Maybe the software is a bit too eager with manual editing of posts?


Why isn't my variable in a function capable of storing a value that I can use later?

So, this is the code I've got difficulties with:  import optarse import subprocess  def get_arguments():     parser = optparse.OptionParser()     parser.add_option("-i", dest="interface")     parser.add_option("-m", dest="new_mac")     (options, arguments) = parser.parse_args()  def change_mac(interface, new_mac):     subprocess.call(["ifconfig", interface, "hw", "ether", new_mac])  change.mac(options.interface, options.new_mac)   As far as I know, the variables options & arguments are storing the values of whatever parser.parse_args() returns. Now, whenever I call this program in my terminal, it's giving me an error. It's saying that the name options is not defined. How is this possible?   PS: I know the solution is to work with return parser.parse_args(), but I'm just trying to understand why the (options, arguments) = parser.parse_args() doesn't work.  Thanks in advance!


Why did the Architect tell Neo that Trinity is inside the Matrix?

In the 2nd film of Matrix series, Matrix Reloaded, at time 2:18:15, the architect told Neo about Trinity:     Apropos, she entered the Matrix to save your life at the cost of her own.   This makes Neo really upset, as he responds:     ...No   and chooses another door. What was the intention of the Architect? I feel like it was better for the Architect to let Neo choose the door that brings Neo to the source and the salvation of Zion.   So, what was the Architect intention to somehow make Neo choose another door? He could have hide the truth that Trinity entered to the Matrix and make him choose the first door.


/usr/bin/find invocation doesn't work when used with command substitution

In a script, I have:  CMD='/usr/bin/find /etc -type f -exec /usr/bin/md5sum {} \; '  MD5=$("${CMD}")   But the script gives the error:  -bash: /usr/bin/find /etc -type f -exec /usr/bin/md5sum {} \; : No such file or directory   However the contents of the $CMD work when typed verbatim at the command line, i.e.  /usr/bin/find /etc -type f -exec /usr/bin/md5sum {} \;   Correctly generates a list of md5 hashes.  I've tried everything I can think of, including escaping the backslash and semicolon in the string, but can't seem to get it to work.  I've also tried invoking the command with backticks, which doesn't change the result.  What am I doing wrong ?


How would you say this in another way:  'I'm rooting for France tonight.' 'Oh yeah? I'm with Belgium.'  Other than supporting, of course.


Writing my first script so I'm sure this is a basic question, but can someone please explain to me why I can:  cd ~ cd bin cd ~/bin cd 'bin'   But not  cd '~' cd '~/bin'   I need to cd to a directory path with a space in one of the directory names, so I need the quotes (it's Windows Program Files under wine). I can get around it with two cd commands, but why can't I put ~ in quotes?  If I type cd '~' (or cd "~") I get:  bash: cd: ~: No such file or directory


Is there a word/idiom for someone who thinks long and hard before spending money?

My colleague and I were discussing about certain types of customers in the IT industry. You have to work extremely hard to convince them so that they think about opening their wallets .  However, they should not be mistaken to be stingy (carries a negative connotation). Cost-conscious is a closely related term but is a bit wordy. Another word that I considered is shrewd but I don't know if it fits my context well.  Usage Sentence:     Nowadays, IT customers are becoming increasingly ________. They demand more for less and probably think a zillion times before reaching for their pockets. If they are not convinced 100%, they simply won't open their wallets.    Is there is a noun or an adjective to describe such people? I am also open to using idioms, if there is one that conveys the intentions well.  N.B:  I am looking for words with neutral to positive connotations.


Where Self-plagiarism Begins and Where it Ends

Academics sometimes publish popular books based on their own research, but not always cite properly themselves, even when book references other authors properly. Moreover, sometimes I can see that one author publishes very similar (but not same) papers on the same topic, without self-referencing, even though it can be seen that the author recycles some of hers/his ideas. Even respectable people in the profession do it.   Given this where is the line beyond which we are talking about self-plagiarism?   On one hand it feels bit wrong to do this even in a small amount. On the other hand I can imagine that it can be impractical, and cumbersome to piously self-reference yourself, and I also worry that that might seem egocentric to the reader.   It is no brainier that copying part of your old article, and submitting it as new is clearly wrong. On the other hand it does not seems to be wrong using the main ideas, quotes (or chapter titles), or paraphrasing minor ideas of your earlier papers to publish a book without using the same referencing standards for yourself as you use for other authors.  Any opinion on this? Should I always reference myself as well as I do others, or is it ok to be more lenient on yourself as long as it is not more excessive then it is usual in the field? Do you think that this depends mostly on the context?


In one city, $N$ Petya, Vasya and Tolya hide from zombies in an underground bunker. But they have no connection with the outside world and they don’t know if the zombies remained in the city or left. They decided that someone needs to go out and find out the situation. they will throw a coin. Think about how to organize the tossing process so that they have an equal chance of being on the surface?   I tried to count the probabilities but nothing came of it . Please help to solve it.


App crashes editing a comment with spelling error

I added a bounty to the issue a while back, it still isn't fixed. Could you please look into this, thanks   App Version: 1.0.89 Device Manufacturer: Google Device Model: Pixel   OS Version: 7.1.1 (3636322)


Book Series identification, late 80s, early 90s

I read a series of 5 novels that began with a space pirate kidnapping a woman from Earth, using her horribly, selling her or perhaps losing her to anothe pirate and her tale grew more awful... Each time you thought her plight could not get worse, the author twisted it more. The protagonist also went through many trials by the end of the series. The protagonist's name was Nick and I don't recall her name. She did eventually triumph.   Anyone know? TIA if so!


If the Landé $g$-factor of an electron is its magnetic moment due to its inherent quantum spin, and its spin is its magnetic moment, why isn't it 1?

I was taught that the 'spin' of an elementary particle was its inherent, unalterable magnetic moment due to its physical spin, or angular momentum, that may or may not actually exist. Therefore, if the quantum spin of a particle is not directly observable (because it probably doesn't exist, as such), but is measurable as its magnetic moment due to its seeming physical spin, how can its gyromagnetic ratio, or $g$-factor, be anything other than one? What am I missing here?


While watching the Liverpool vs Manchester United Premier League game in January 2020, I got confused on the offside rule when Salah scored a goal.  Salah was well offside when Allison passed the ball to him. I'm confused as to how that is not an offside. I thought it won't be offside when goalkeeper passes the ball only when it's a goal kick, but it wasn't a goal kick, Allison got the ball in open play after deflecting from one of the Manchester players.


Free space in bar-chart with empty entries

I would like to plot some data set with the ybar option of pgfplot. But not all entries are nonzero. The zero entries waste space between the bars and when the plot gets crowed it is not clear anymore which bar belongs to which group. Furthermore the groups seem not centered around their description. How do I free the space of the zero entries?  \begin{tikzpicture} \begin{axis}[ybar,ymin=0,xtick={0,1,2,3},xticklabels={a,b,c,d}] \addplot coordinates{ (0,3) (1,3) (2,3) (3,3) }; \addplot coordinates{ (0,2) (2,2) }; \addplot coordinates{ (0,1) (1,1) }; \end{axis} \end{tikzpicture}     The potential solution in  leads only to errors on my setup.


When I run apt-get update, I get this error message:  Err:18 http://dl.google.com/linux/chrome/deb stable Release.gpg                   The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6494C6D6997C215E   I understand what causes this issue. I wonder how to fix it.  EDIT:  I tried the most upvoted solution provided in the duplicate link:  sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 6494C6D6997C215E   I got this new issue which does not seem to be resolved on this website according to the posts I saw:  Executing: /tmp/tmp.jyolnTyZuJ/gpg.1.sh --keyserver keyserver.ubuntu.com --recv-keys 6494C6D6997C215E gpg: requesting key 997C215E from hkp server keyserver.ubuntu.com gpg: keyserver timed out gpg: keyserver receive failed: keyserver error


Show that $2^{(p-1)/2} \equiv 1\: \mathrm{mod}\:p$?

Let $F_n = 2^{2^n}+1$ be the $n$th Fermat number for $n \geq 2$ and $p$ a prime factor of $F_n$.  How can I show that that $2^{(p-1)/2} \equiv 1 \:\mathrm{mod}\:p$?


Prove that $(X\times Y)\setminus (A\times B)$ is connected

I'm reading topology of Munkres and I have a problem that stuck me for a while. I'm so greatful if anyone can help me with this.     Let $A$ be a proper subset of $X$, and let $B$ is a proper subset of $Y$. If $X$ and $Y$ are connected, show that $$(X\times Y) \setminus (A\times B)$$ is connected.   Thanks so much for your consideration ^^


Is there a Linux or Ubuntu build for the Nexus 7 2012 which supports touch?


How do I get Views content items in "my language" but fall back to "default" if the content isn't translated?

This is probably very easy but endless searching has proved fruitless - there's lots of UI changes between the D7 and D8 versions of these modules it seems.  What I want to do is create a blog in two languages. The default language is English. Mostly, the author will be translating the articles to Italian. However, I would like to create the blog view such that:   only one translation shows in the list, per node if viewing the site in italian but there is no translation of a specific list item to italian, the english version shows (fall back to default language) if he's only written an italian version, show that anyway instead of the non-existent english one   The options in views are similar looking to everywhere else, but in those other places this isn't really an issue. In standard nodes, the fallback kicks in automatically. Any ideas of how to configure this?


How do we interpret this result?  Also, is a p value of .000 an error?   The hypothesis should be tested with a .05 level of significance.


Are 401(k) & IRA Contribution Limits Mutually Exclusive?

Are the $18,000 401(k) 2017 limit and the $5,500 IRA limit mutually exclusive for a combined limit of $23,500 (under 50)?   Or are they inclusive, meaning $5,500 in an IRA, would limit a 401(k) to $12,500?  I'm also assuming employee matching count towards these limits. Is this correct?


I am finding two completely contradicting posts while googling regarding health risks to the heart for excess consumption of eggs:      So, are eggs good for heart health or bad? Now-a-days I am taking two eggs in my meal everyday. Had been curious to know, how safe is it?


How do I select the number of components for independent components analysis?

In the absence of good a priori guesses about the number of components to request in Independent Components Analysis, I'm looking to automate a selection process.  I think that a reasonable criterion might be the number that minimizes the global evidence for correlation amongst the computed components. Here's pseudocode of this approach:   for each candidate number of components, n:     run ICA specifying n as requested number of components     for each pair (c1,c2) of resulting components:         compute a model, m1: lm(c1 ~ 1)         compute a model, m2: lm(c1 ~ c2)         compute log likelihood ratio ( AIC(m2)-AIC(m1) ) representing the relative likelihood of a correlation between c1 & c2     compute mean log likelihood ratio across pairs Choose the final number of components as that which minimizes the mean log likelihood of component relatedness   I figure this should automatically penalize candidates larger than the "true" number of components because ICAs resulting from such candidates should be forced to distribute information from single true components across multiple estimated components, increasing the average evidence of correlation across pairs of components.    Does this make sense? If so, is there a faster way of achieving an aggregate metric of relatedness across estimated components than the mean log likelihood approach suggested above (which can be rather slow computationally)? If this approach doesn't make sense, what might a good alternative procedure look like?


Set today's date as default date in jQuery UI datepicker

I just want today's date  to be the default value in the input that is using jQuery UI's datepicker:  <input id="mydate" type="text" />   I tried the below code but it didn't work:  var currentDate = new Date();   $("#mydate").datepicker("setDate",currentDate);


Expiry time in notify-send notifications

On my HP computer running Ubuntu 12.04, the brightness and volume increments were much higher than I wanted. On top of that, the notification for the volume was just plain wrong (0% sound did not correspond to 0 on the progress bar). So I decided to override these options with my own commands. I used CompizConfig Settings Manager to add custom commands to the brightness and volume keys (this couldn't be done in the regular settings because these keys were handled by the BIOS, unlike normal function keys). I used xbacklight to control the brightness and amixer to control the volume.  The problem is that the nice notify-send notifications don't show up when I manually set the brightness/volume, so now I have to do that myself too. However, there are two problems with notify-send:   The expire time option  You have to wait until a notification is finished before the next one comes up   Before I overrided the brightness/volume keys, the system was able to send notifications without these two restrictions. Notifications disappeared within 3 seconds (instead of the default 10), and if I double tapped the volume or brightness button, the progress bar would immediately change to the new brightness (instead of showing the old progress bar for 10 seconds and then showing the new one).  Since the system was able to do it, I was wondering how I can achieve the same type of notifications?


How to find $f(x)$ from below relation ? $$f\left(\frac{3}{x}\right)+f\left(\frac{x}{2}\right)=\frac{9}{x^2}+\frac{x^2}{4}-2$$ I have two question about this .I find $f(x)=x^2-1$  that work fine ,but $\\(1)$ how can be sure that there is no other solutions ?  $\\(2)$ How can find $f(x)$ in general ?


Baker Gill Solovay $P^B \ne NP^B$ relativization, what class is $B$ in?

A recent question asks . This question wonders how to put one use of it on firmer ground.         In the  that there exists a language $B$ such that $P^B \neq NP^B$. To best available knowledge, what complexity class is $B$ in?   Fill in the blank ("$?$") if possible, or analyze as best possible: if there existed a $B'$ in class "$?$" such that $P^{B'} \neq NP^{B'}$, then $P \neq NP$.


It's a program that is a sports league, a group of teams plays through a Schedule of Games and determine the winner.  The program runs fine to the point where the final output won't let me see the winner, it shows this instead:     The season winner(s) with 9 points: [Ljava.lang.String;@e73f9ac   I changed it to teams.length which made the program work but it would show me the teams (i) number instead of the string name like "Vancouver".  Thanks in advance.      }      int peak = 0;                                     int[] total = new int[teams.length];               for (int i=0; i<teams.length; i++){                           total[i] = 2*wins[i]+ties[i];        if (total[i] > peak) peak = total[i];        System.out.println(teams[i]+" - " + wins[i] + " wins, " + losses[i] + " losses, " + ties[i] + " ties = " + total[i]);   }        System.out.println("The season winner(s) with " + peak + " points: " + teams);      for (int i=0; i<teams.length; i++){     if (peak < total[i]) peak = total[i];   }        }  static int indexOfTeam(String team, String[] teams){     for (int i=0; i<teams.length; i++)     if (team.compareTo(teams[i]) == 0) return i;     return -1;   } }


Batch exporting scene collections or selected objects using glTF-Blender-IO

I'm still new with python and scripting. I tried editing the . Since I'm exporting tons of object groups, I need each of scene collection or selected objects to be exported as an :  import bpy import os  # get the path where the blend file is located basedir = bpy.path.abspath('//')  # deselect all objects # bpy.ops.object.select_all(action='DESELECT')      # loop through all the objects in the scene scene = bpy.context.scene for ob in scene.objects:     # make the current object active and select it     scene.objects.active = ob     ob.select = True      # make sure that we only export meshes     if ob.type == 'MESH':         # export the currently selected object to its own file based on its name         bpy.ops.export_scene.gltf(                 filepath=os.path.join(basedir+'gltf-individual', ob.name + '.gltf'),                 use_selection=True,                 )     # deselect the object and move on to another if any more are left     ob.select = False   Q: Can someone help me with this?


"Requires 50 reputation" to comment on deleted posts

So I recently saw add comment (requires 50 reputation) on a deleted answer. After looking around a bit, it seems to be on all deleted posts now (only deleted posts, normal posts still say just add comment).  I'm sure it wasn't there before (I think it just said add comment (unclickable) or possible nothing).  It is also on , presumably the root cause is the same.  And yes, I do have more than 50 reputation (in case anyone was wondering).  Just to clarify, requires 50 reputation obviously shouldn't be there for users with 50 or more reputation. Choices:   Display nothing Unclickable add comment - probably not ideal Unclickable add comment (disabled for deleted posts) or something along those lines   FYI - You may be somewhat confused right about now if you can't  yet.


Is there a formula for solving the congruence equation $ax^2 + bx + c=0$?

Using the quadratic formula, we have either 0, 1, or 2 solutions. I wonder if we could use it this formula for congruence? Or is there a formula to solve quadratic equation for congruence?  Edit Assume that $ax^2 + bx + c \equiv 0 \pmod{p}$, where $p$ is prime with $(a, p) = 1$, then is there a formula for this equation?    Thanks,