Execute command from file in current shell

I want to executed command from file (which is script) in current shell in terminal.  Example: I have file ch_dir contains following:  #!/bin/bash cd /usr   Now if I execute file usually as following then it executes commands in different shell:  pandya@pandya-desktop:~$ ./ch_dir pandya@pandya-desktop:~$   Here cd /user is executed in different shell.  But I want to execute in Current shell. How do I do that?  Note: Here cd is only used to explain. Question's aim is to execute any command in current shell


Let $S$ and $T$ be linear map defined on hilbert space $H$ s.t. $\langle Su,v \rangle=\langle u,Tv\rangle $ $\forall u,v \in H$. Then show that both $S$ and $T$ are bounded.  $\textbf{TRY-}$ If I can show $S$ is bounded than $T$ is bounded but I am unable to show $S$ is bounded. I was working on it but getting nowhere. Any help is appreciated. Thanks!


Question list on Stack Overflow is not showing new question

On Stack Overflow the last question was asked approx 1 hour ago. It is not getting updated. Since the volume of the users are a lot, I can't believe that nobody has asked question since last 1 hour. I think there is some problem.   Please look into it.  Edit : Now it is showing lastest question as 30 mins ago. But on the other hand same kind of problem is started on meta site. The active tab is not getting refresh with current discussing question.


Does anyone know why, using SQLServer 2005  SELECT CONVERT(DECIMAL(30,15),146804871.212533)/CONVERT(DECIMAL (38,9),12499999.9999)   gives me 11.74438969709659,  but when I increase the decimal places on the denominator to 15, I get a less accurate answer:  SELECT CONVERT(DECIMAL(30,15),146804871.212533)/CONVERT(DECIMAL (38,15),12499999.9999)   give me 11.74438969


Duplicate answer as late answer from new user

I wonder how to handle duplicate, late answers from new users? Today I reviewed  which is almost an exact duplicate of . The reason these late answers are reviewed from my understanding is to prevent new users from adding low quality answers. In my opinion a duplicate (actually a sixlicate because there are six 'duplicate' like answers) answer to a 1.5 year old post validates as being low quality and unwanted.  So I doubted a bit what to do since there is no flag for 'duplicate answers' and looked up .     The only times I'd seriously consider flagging is when the duplicate is posted days or weeks after the original.   After giving it a bit of thought I chose to flag the answer, after all I'm reviewing this late answers to sort out the hidden gems between the junk. But the flag got declined because:      flags should only be used to make moderators aware of content that requires their intervention   In my opinion the moderators intervention should have been deleting the post, after all we want users to post useful answers, but it seems I'm wrong.   So my question is: When I'm reviewing late answers from new users and they give a duplicate answer, what should I do with it? I'm new to the whole Stack Overflow reviewing and if I do so I like to do it right.


My theme is set up so that if I add javascript files through the info file they are loaded at the bottom of the page. This is generally what I want however I want to load a few specific javascript files in the head. Is there a 'standard' way of doing this? I would like to use the normal minification and aggregation if possible.


Is REST a better approach to doing Web Services or is SOAP?  Or are they different tools for different problems?   Or is it a nuanced issue - that is, is one slightly better in certain arenas than another, etc?  I would especially appreciate information about those concepts and their relation to the PHP-universe and also modern high-end web-applications.


Software for measuring internet traffic?

I'm interested in finding a free piece of software for Windows XP & 7 that allows us to measure both incoming and outgoing internet traffic, but not traffic between users of the local network.  I live in a shared household with three others, and we're interested to see which of us is using the largest amount of our monthly internet quota. We're all happy to install the necessary software.  Any suggestions?


On the Subtlety of Verbal and Material use During Spellcasting

In a campaign amongst my friends and myself, I am playing a divination wizard who enjoys utilizing suggestion in social activities from time-to-time. In this particular scenario, my party and I were in a were in a church speaking to a Cardinal in his office. A monk friend of mine decided to say some heretical words which prompted the Cardinal to yell "Guards!" thus beginning a train of 15 guards rushing into the room. In this time, I wanted to cast suggestion as a means of evading subsequent conflict. Whether or not my suggestion would have been seen as reasonable is not a part of this question, but instead I am interested in the manner in which the guards would have viewed this spell cast. Suggestion, of course, is composed of a verbal component and a material component which is then followed by up to a two sentence suggestion. The immediate feedback from the DM upon attempting to use suggestion is that the cast would be obvious to the guards as spellcasting in itself is not a secret to bystanders thus no opportunity to roll out any plays. DM ruling accepted with some pushback, but we tabled this until after the session where we basically agreed that in situations such as a busy bar or a busy marketplace I could potentially get away with pulling off a suggestion without drawing too much attention to myself. Seems reasonable to me. Now my issue lies in how this was handled. If these guards are rushing in, certainly making some noise, they don't necessarily know I'm a wizard before hand, and I'm not facing these guards; should my verbal and material components use be painfully obvious to the guards or is this something that can be done with some subtlety given the situation?


I have been struggling for a while to find any resources on how to remove this strange question mark square symbol: �  Standard str_replace and preg_match don't work. Can anybody assist in this? Settings the charset header('Content-Type: text/html; charset=utf-8') doest not work either. Nor does:ini_set("default_charset", 'utf-8');  I should mention I am using curl to request the data from a webpage.  Thanks


Showing directional line symbol in ArcGIS for Desktop?

Is this possible in ArcGIS to have variable number of arrows on the line to show direction?  This is an ArcGIS example, where I can have fixed (1,2,3,4,5...) number of arrows and it stays the same doesn't matter what the line length is. First and last always stick to the end, doesn't help with network mapping, where there is usually the node to show. Having just one in the middle is never enough, check line at the right...   No such issues with ArcView 3:


What to do about a switch without neutral, in MA, USA?

I'm upgrading switches in my older (1978) home, putting smart switches in. I have found many "interesting" wiring situations, some I have remedied, some I have just left as-is.  Recently I opened a junction box with a single pole switch, controlling accent lighting above my kitchen cabinets. I was surprised to see a single 12-2 cable feeding the box. The black wire is hot, and the white wire is the load, with the bare ground protecting the switch.   What should be done here? Luckily, I'm able to add a smart dimmer because my brand (Lutron Caseta) doesn't need a neutral.  Is this wiring safe? I believe so. Up to code in Massachusetts? There's got to be a white wire connected to a black or red, somewhere else in the house (I haven't found out where yet) to make this work.  What needs to be done, here? Do I need to label the white wire?


Does Stack Exchange allow for answers which question the validity or stance of the original question?

One thing I keep running into on this site is that some questions are merely asked so that a persons opinion can be validated.  I don't ever say I'm right and you're wrong when I reply to a question, but there are times I answer with a response that basically says, 'this question isn't really valid for x reason', or 'there is something more important to consider than what you're asking'.  In my mind I'm offering an answer to the fundamental validity of the question.  Most times, as I guess I should expect, my answer is down voted.  However, I do feel that it is important to step back sometimes and evaluate the validity of a question and the foundation it is asked on.  Is this accepted and acknowledged in the community, that some answers are 'No you can't', or 'that is not a valid question because of the premise it is asked on, because...'?  EDIT Example:  Like for instance, in parenting area if someone asks something obvious like 'How do I teach my 3 month old the alphabet'? My answer would be    you can't  you should not be trying to do that.   That was an obvious example, but there are other situations that are not as obvious, yet still 'you shouldn't do that or try that' may still apply or at least be a valid consideration


How do I setup a sub-domain on my server and install wordpress to it?

I have a web server with a paid domain and all and I would like to create a subdomain for it. How can I do this and install wordpress onto it?


How to calculate $ \sum_{k=1}^{n} \sin(2k-1)x $?

How do i calculate $ \sum_{k=1}^{n} \sin(2k-1)x $, using $e^{i*x}=cos(x) + i*sin(x)$?


I am having difficulties in the confirmation of two passwords in java where my condition statement in if else looks like not working

it always shows the infobox that i am always failing to get the string value of password and password 1 to confirm if those two are the same and then if it is the same it will insert those values into my local database @FXML     private void handleButtonActionRegister(ActionEvent event) {         String email = textUserRegister.getText();         String password = textRegisterPassword.getText();         String password1 = textRegisterPassword1.getText();         if (password != password1){             infoBox("Password doesn't match!", "Failed", null);}         else{         String sql = "INSERT INTO employee VALUES (?,?)";         try{             preparedStatement = dbconnect.prepareStatement(sql);             preparedStatement.setString(1, email);             preparedStatement.setString(2, password);             resultSet = preparedStatement.executeQuery();                          Node source = (Node) event.getSource();              dialogStage = (Stage) source.getScene().getWindow();             dialogStage.close();             scene = new Scene(FXMLLoader.load(getClass().getResource("WelcomePage.fxml")));             dialogStage.setScene(scene);             dialogStage.show();          }catch(Exception e){e.printStackTrace();}}     }


Get 5th to last to 3rd to last elements from a list of unknown size

I have a list of unknown length which I want to get the 5th to last, 4th to last, and 3rd to last elements from:  So if my list is like. a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]  I want to get. b = [6, 7, 8]  I can get this with b = a[6:9]  But the issue is my list could contain any number of items, so it could be.  a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13]   and in this case b should be [9, 10, 11] which b = a[6:9] does not give.  How can I always get the 5th to last third last items in a list, my list will always be over 5 elements long.


Remove or delete a review from my iTunes app?

How can I remove a customer review from my App in iTunes?  I sent a message via Report a Concern and nothing happened.


Can utilitarianism be manipulated to do awful things

Let's say it would take the torture and death of 100 million people to find the cure for death and aging. The cure would be cheap and easy to make and is easily distributed to the rest of the world's population.  With utilitarianism, it seems like it would be a morally just thing to do. Does utilitarianism have some kind of caveat to deal with that kind of situation? Are the rights of the few protected? A similar situation would be a doctor killing someone to harvest their organs to save the lives of multiple people. Is that morally just with utilitarianism?


Remove Extra Spaces Before and After javascript string

var $one = $('#oneClueShow');     var x = $("#clueOneInput").find('input[type=text]').val();     if(x == 'D R' || x == 'd r'|| x == 'D r'|| x == 'd R'|| x == 'd'|| x == 'r' || x == 'd R' || x == 'T A')   Above is a snippet of java/ I have. What it does is takes an input  -- then checks for a match. The bug I'm looking to resolve is if there are spaces after or before it isn't recognized.  For example within the input someone can type 'D R' no problem. If a space is added like so 'D R ' then it no longer recognizes the input.  Is there something I can do to affect the input to ensure no space before/after prior to button click? I've been looking into replace, but can't seem to get it going.  A reference for what I've been looking at :


Overlapping text in side-by-side view of edit review queue

While reviewing a suggested edit on , I noticed that the question's title has a long, non-breakable word in it (specifically, com.example.accountproject.models.interfaces.MemberSv, a fully qualified Java class name). This causes the text of the two side-by-side posts to overlap:


Prove that $\left\{\frac{a}{2^b}: a \in\mathbb{Z}, b \in\mathbb{Z}_{\geq 0}\right\}$ is dense in $\mathbb{R}$.

What am I looking for exactly?  The hint I was given: show that we can find such a fraction between any two given real numbers.


Does Ubuntu handle 'bash_profile' differently from OS X in subshells?

On my OS X system, when I use a subshell (for example with screen), the settings in my .bash_profile are inherited, but on Ubuntu, they are not, and in order to get the same behavior I have on OS X I have to add  source ~/.bash_profile   to the start of my .bashrc.  Does Ubuntu (Linux) handle the relationship between .bash_profile and .bashrc and their use in subshells differently from OS X (BSD)? Is there an Ubuntu setting that makes it behave like OS X in this regard so that I can avoid the above line?


If $a+\sqrt{a^2+1}= b+\sqrt{b^2+1}$, then $a=b$ or not?

It might be a silly question but if $$a+\sqrt{a^2+1}= b+\sqrt{b^2+1},$$ then can I conclude that $a=b$? I thought about squaring both sides but I think it is wrong! Because radicals will not be removed by doing that! Can you help me with proving that $a=b$ or not? Actually I'm going to prove that $x+\sqrt{x^2+1}$ is a $1$-$1$ function.


Used (probably) inappropriate charger, touchscreen went crazy, permanent damage?

I used a plug with USB output than may have been inappropriate (output DC5V +/- 0.20V DC500mA +/-30mA). While it was plugged in, the touchscreen stopped working properly (touching one part of the screen would trigger another), I guess because the voltage was wrong? Is there any danger that I did some permanent damage to the phone or the battery? It wasn't plugged in for long.


I am running a small business unit on agency recruitments. Need to know about setting up a VOIP service to call USA/Canada..  We have around 20 phones on line and we operate from bangalore.  What tool/software is used for this ?? What are the hardware requirements?  Appreciate your help.  Alvin


Prove that 2/π ≤(sinx)/x ≤ 1 for all |x|≤ π/2.

Real Analysis Prove that 2/π ≤(sinx)/x ≤ 1 for all |x|≤ π/2 ? Just need the 2/π greater than part.


Whats the difference between Unix, Linux and Ubuntu?

What is Unix, Linux, Ubuntu?  Are they the same thing or different versions or completely different stuff?  This has always made me confused, any explanation would be great.


how to get sfdc space utilization via SOAP API?

In my requirement, i need to get SFDC space utilization and display data into third-part systems. But, after i searching SOAP API, I  didn't found any api description about space utilization. guys, if you know it about this api, would you please let know.   Many thanks


Does Mowing the Grass have benefits beyond aesthetics in RollerCoaster Tycoon?

In the original PC release of RollerCoaster Tycoon, if playing in a scenario with a lot of grassland, I would ensure my handymen did not mow the grass as their other services seemed more beneficial to keeping the park tidy, as well as making sure the handymen did not wander off the paths. In the android release, the handymen by default do not mow the grass (that duty by default is set to off).  I know the guests will remark on the scenery and vandalism, but I have not seen anything to suggest that mowing the grass has an effect on the guests or ride construction.  My question is; does mowing the grass have any effects apart from just making the park look tidier? Does allowing it to overgrow have any negative effects?


I need to write an article with APA citations. I have sample code that works fine with style=authoryear, but if I switch to style=apa I get the following error message:   Error Line 21 ! Undefined control sequence.<argument> \printdateextralabel   I'm using TexMaker with biber. I've gone through example after example and I can't figure out what's wrong. I suspected it was with TexMaker or MiKTeX, but I just uninstalled and reinstalled both programs and I'm having the same issue. The same error message always pops up with the line number after \printbibliography. I tried copying corrected MWE's from other questions (such as  answered by Alan Munn) and I get the same error.  I included a MWE and my .bib file (borrowed from another thread) below.  File MWE:  \documentclass[article,12pt,letterpaper]{apa6} \usepackage[american]{babel} \usepackage{csquotes} \usepackage[style=apa,natbib=true,backend=biber]{biblatex} \DeclareLanguageMapping{american}{american-apa}   \title{Annotated Bibliography 1} \author{Joe Smith} \affiliation{Spectacular University} \addbibresource{bib.bib}  \begin{document} \abstract{abstract goes here} \maketitle this is a test \cite{Kim1999188} \printbibliography \end{document}   bib:  @article{Kim1999188, title = "Absorption of water vapour into lithium bromide-based solutions with additives using a simple stagnant pool absorber ", journal = "International Journal of Refrigeration ", volume = "22", number = "3", pages = "188 - 193", year = "1999", note = "", issn = "0140-7007", doi = "10.1016/S0140-7007(98)00061-9", url = "http://www.sciencedirect.com/science/article/pii/S0140700798000619", author = "Jin-Soo Kim and Huen Lee and Sun Il Yu", keywords = "Absorption", keywords = "Water", keywords = "Lithium bromide", keywords = "Absorption", keywords = "Eau", keywords = "Bromure de lithium " }      Here is a link to my .


How to make certain apps not be affected by your theme?

I'm using the Arc theme for Ubuntu, and for most apps it is beautiful. My problem is that for some, it makes them unusable.  I just setup Enpass for password management. But the Arc theme makes it so hard to use, from a visual perspective.  So what can I do to fix this? I want to exclude specific apps from the theme entirely.  I'm on Ubuntu 16.04.1.


Google analytics lost conversions after implementing social login

we have recently implemented social login to our website. We are running ads to that website and after implementing the social login we lost all conversion data - everything is accounted to facebook.  Also we have kind of "sub-website" shop-domain.com where are some products that are sold separately and user can migrate between domain.com and shop-domain.com and vice versa. Can this loose conversions as well?   My question is:  how can we configure analytics / ads / website to correctly count the conversions?  What have I done:  In google analytics documentation I found something called linker to fix user migration between domains and page referrer after login. But it doesnt seem to help  gtag('config', 'UA-XXXXXXX-1', {         'linker': {             'domains': ['domain.com', 'domain.eu', 'shop-domain.com', 'shop-domain.eu']         },         'page_referrer':'domain.com'     });   Thanks for any suggestions


How can I install ffmpeg on Lubuntu 14.04?

It seems that the original ffmpeg has been dropped by Debian for the moment (in favour of the fork libav)  but will be back in 15.  Some people seem to think ffmpeg is deprecated or stale: it's not, it's just that in 2011,  a group of devs decided to fork it as avcodec (libav).  I use get_iplayer for BBC downloads and that requires ffmpeg for its automated format conversions. So I was a bit surprised to find that a brand new install of Lubuntu 14.04 (LTS)  doesn't include ffmpeg.  How can I install ffmpeg?


Let $A$ a semilocal ring and $M_1,M_2,\dots,M_n$ are all of its maximal ideals then the Jacobson radical $rad(A) =M_1M_2\cdots M_n = M_1\cap M_2\cap \cdots \cap M_n$  I tried to use the Chinese Remainder Theorem, How can I solve this?  Thanks for your time and help.


How to calculate the radius of the image circle?

I am a beginner in this topic, so I dont know if it is possible what I try to do.  First of all, I have the following HF35HA-1B lens:   It says the maximum sensor size is 2/3", but I have a non-standard 25mmx25mm image sensor, so I want to do some hackings. I know the flange focal distance of Cmount lenses is 17.526mm, but what if I move the image sensor further back from the lens? I suppose the further I go from the lens, the bigger image I get. But how can I calculate the radius of the image circle? I did a very easy test, in which I could make sure that even if I move the sensor back the image is focused for closer objects, so I think that is not an issue. But I would like to calculate the image circle to make sure the image sensor is in the image circle. Is it even possible what I am trying?:)  I would appreciate any comments!


BibLaTeX - Backreferencing citations from frontmatter with Greek language

I've encountered a problem with backreferences from my bibliography (biblatex, biber) to the frontmatter of my document when using "greek" as a babel option in my document. The following seems to be a minimal example. It does not matter if greek is the main language or an additonal one (see commented line).  \documentclass{book} \usepackage[     backref=true,     backend=biber, ]{biblatex}  %\usepackage[greek, english]{babel} \usepackage[greek]{babel} \usepackage[utf8]{inputenc}  \addbibresource{\jobname.bib} \usepackage{filecontents}  \begin{filecontents}{\jobname.bib} @book{key, author = {Author, A.}, year = {2001}, title = {Title}, publisher = {Publisher}, } \end{filecontents}  \begin{document}  \frontmatter  Here I reference the book \cite{key}.  \mainmatter  \printbibliography  \end{document}   The console output starts  This is pdfTeX, Version 3.14159265-2.6-1.40.17 (MiKTeX 2.9.6100 64-bit)   and the error is  (backrefstartmatter.aux  ! LaTeX Error: Missing \begin{document}.  See the LaTeX manual or LaTeX Companion for explanation. Type  H <return>  for immediate help.  ...                                                l.13 ...}{{\fontencoding  {OT1}\selectfont  i}}{1}   The corresponding section of the .aux file is   \abx@aux@backref{1}{key}{0}{{\fontencoding  {OT1}\selectfont  i}}{1}   Any ideas? Thanks in advance.


Perfect separation of a dummy variable with the dependent variable in a binary logistic regression produces high insignificant estimates

I have the following setup: I have a binary logistic regression analysis with a couple of independent variables. They include a nominal variable that is coded in a dummy form with $k-1$ predictors. It happens to be the case that one dummy is all 1's with the dependent variable, i.e., perfect separation. This produces a very high estimate (~16) with very high standard errors (~1250). Albeit insignificant, this looks a little strange. It is only a control variable, therefore, I don't want to complicate things overly... Is there a way to handle this "problem"? Do I violate any assumptions by including such a dummy?


I watched this video by Matt Parker recently:    He calculates $i^i$ and his answer is around ~1/5 well more precise $e^\frac{-\pi}{2}$ which uses  $e^{i\theta} = \cos(\theta)+i\sin{\theta}$  where $e^{i\frac{\pi}{2}} = i$  so that $i^i = e^{\ln{i^i}} = e^{i\ln{i}} = e^{ii\frac{\pi}{2}} = e^{-\frac{\pi}{2}}$ which is around 1/5  whatever. If you use   $e^{i\theta} = \cos(\theta)+i\sin{\theta}$  you can also argue that  $e^{i\frac{5\pi}{2}} = i$  and so  $i^i = e^{-\frac{5\pi}{2}}$   which is obviously different to $e^{-\frac{\pi}{2}}$.  Where is the error?  WolframAlpha btw agrees with Matt ;)


I was testing an example snap when I interrupted Ctrl+c when it had downloaded and was reading the packages. The output showed some python stuff. After that I installed the packages normally. Apt is working fine, checked the logs and they look good. I also ran dpkg --configure -a and saw no output. So am I good? I always have this feeling that something can go wrong and I wouldn't know about it.


My UK visa was rejected once in 2013 and twice in 2018. how should I apply again


Invariant subspace of group representation

Let $G:=S_n$ and let $V:=k^n$.   Suppose characteristic of $k$ does not divide $n$.   Define $U:=\{(a_,...,a_n \mid \sum a_i=0\}$  If $\exists$ subspace $U' \subseteq U$ s.t.  $\{e\} \neq U'$ and $gU' \subseteq U'$ $\forall g \in S_n$,   Then $U'=U$.   So $\subseteq$ is clear,   Pick $0 \neq \alpha \in U$, then $\alpha = (a_1,...a_n)$  Since characteristic of $k$ does not divide $n$, we know all entries cannot be equal, furthermore we know all entries cannot be zero and. Where do I go from here to ensure $\alpha \in U'$ ? i.e., $U$ has no nontrivial proper invariant subspaces.


$\zeta_5$ has degree $4$ over $\mathbb{Q}$ and $\zeta_7$ has degree $6$ over $\mathbb{Q}$

To give some background, I am attempting to solve the problem from Artin's algebra textbook which was already asked in this link:  Now, I would like to prove the following two claims which are not obvious to me. If I can prove these, I will be able to show that $\zeta_5\notin \mathbb{Q(\zeta_7)}$ as needed. I suspect that both claims will have similar proofs.  Claim 1: $\zeta_5$ has degree $4$ over $\mathbb{Q}$ Claim 2: $\zeta_7$ has degree $6$ over $\mathbb{Q}$  Attempt to prove Claim 1 Let $α=\zeta_5$. I would like to find the monic irreducible polynomial for $α$, but unfortunately I do not know what it is yet. I see $α=cos(\frac {2π}5)+isin(\frac {2π}5)$ and $α^4=cos(\frac {4π}5)+isin(\frac {4π}5)$. Please help me to find the irreducible polynomial, and (ideally) to show that it is irreducible.


Kristin: I just wanted to give you a call and ask how your Chattanooga   trip was.      Susan: Oh, it was great. It was great. It was more fun than   a barrel of monkeys.      Susan: You know, we took Ethan and be-, his being only eight, it was   fun to watch him at different places and see him, y’know, enjoying the   activities.   Why does Susan use "his being only eight" to refer to his age? Shouldn't it be "He is only eight"?  Source: A.J. Hoge, Effortless English, Real English Conversation ()


Is the image of $\Phi_n(x) \in \mathbb{Z}[x]$ in $\mathbb{F}_q[x]$ still a cyclotomic polynomial?

Let $\Phi_n(x) \in \mathbb{Z}[x]$ denote the $n$-th cyclotomic polynomial, and let $\mathbb{F}_q$ be the finite field with $p^k = q$ elements ($p$ prime). Let $\Phi'_n(x)$ be the reduction of $\Phi_n(x)$ mod $p$ (i.e., $\Phi'_n(x)$ is the image of $\Phi_n(x)$ in $\mathbb{F}_q[x]$). Is it true that $\Phi'_n(x)$ is the $n$-th cyclotomic polynomial in $\mathbb{F}_q$; that is, are the roots of $\Phi_n'(x)$ precisely the primitive $n$-th roots of unity in $\mathbb{F}_q$? If so, I want to prove this is the case, but I'm not sure how I'd go about doing this.


problems with "How to create a bootable USB stick on Windows"

I'm looking at    it's a really long time since I've used linux, but to me this is unclear, I've downloaded the app from Pen Drive Linux, but then when I use it, in step two it says "Click 'Browse' and open the downloaded ISO file." but at no point has it told me to download an iso file, or given a link to where I download it from.   The one given in the picture is called precise-desktop.iso, I've no idea if that's the file I'm supposed to be downloading, or if I need to rename the file to this, or if I just need to download a regular ubuntu distribution, which is what I'm doing now.


What is the difference between LILO and GRUB?

I am running a web server under Debian and I currently have GRUB installed.  Should I consider using LILO instead of GRUB? And what are the advantages of each?


Anyone else find naming classes and methods one of the most difficult parts in programming?

So I'm working on this class that's supposed to request help documentation from a vendor through a web service. I try to name it DocumentRetriever, VendorDocRequester, DocGetter, but they just don't sound right. I ended up browsing through  for half an hour trying to come up with an adequate word.   Start programming with bad names is like having a very bad hair day in the morning, the rest of the day goes downhill from there. Feel me?


Custom unique constraint, only enforced if one column has a specific value

Is it possible to have a custom unique constraint as follows? Suppose I have two cols, subset and type, both strings (though the data types probably doesn't matter). If type is 'true', then I want the combination of type and subset to be unique. Otherwise, there is no constraint. I'm using PostgreSQL 8.4 on Debian.


moderncv cover letter recipient data line length

I am writing a cover letter and CV using moderncv. The resulting output wraps the first two lines of the recipient information, making four lines, even though it's unnecessary (in this case). How can I change the output of the recipient data so that the committee name is on only one line and the school name is only on one line?  Here is a MWE:  \documentclass[12pt,letterpaper,sans]{moderncv} \moderncvstyle{classic} \moderncvcolor{black} \renewcommand{\familydefault}{\sfdefault} \nopagenumbers{} \usepackage[utf8]{inputenc} \usepackage[scale=0.75]{geometry} \usepackage{lipsum}  %% Personal data \firstname{New PhD} \familyname{Scholar} \address{31415 Pi Street}{Largeville, ND, 58202} \mobile{+1~(502)~321~1234} \email{scholar@gmail.edu}  \begin{document}  % recipient data \recipient{New Work and Research Studies Search Committee\\E. Pluribus Unum School of Grant Proposals and Other Funding}{Blueberry University\\204 N. Peach Ave.\\Buymore, WI 78115} \date{\today} \opening{Dear Committee Members,} \closing{Regards,}  \makelettertitle \lipsum \makeletterclosing \end{document}


Texworks syntax highlighting not working on windows 8 and 8.1

any latex code I want to view in TexWorks 0.4.5 r.1280 (Miktex 2.9) won't show the syntax highlighting. It compiles just fine but everything line is written in black. On very long documents the highlighting shows for several seconds then the program freezes for short and the highlighting disappears again. Windows compatibility modes did not improve the situation. Does anyone have an idea what's going wrong here?


Using gronwall's lemma to prove inequalities involving max$x(t)$.

Given $\frac{\partial x}{\partial t}+x^3=yx^2$, $x(0)=x_{0}$, where $x$ : $\mathbb{R}^+ \mapsto \mathbb{R}$ and  $y$ : $\mathbb{R}^+ \mapsto \mathbb{R} $ with $\int_{0}^{t} y^2(s) ds < \infty$ for all $t$  if $x(t)$ is continuous function satisfying the above equation in $[0,T]$  $$ \max_{t\in[0,T]}|x(t)|^2 \le |x(0)|^2e^{\int_0^T|y|^2\,\mathrm ds}.$$   $$ \int_0^T|x|^4\,\mathrm ds <|x(0)|^2+\max_{s\in[0,T]}|x(s)|^2\int_0^Ty^2\,\mathrm ds.$$ It seems like it has something to do with Gronwalls lemma.  My first approach was to set $x(t)'<y(t)x(t)^2$ and find bound for $x(t)$, but it did not work nicely.   Can anyone help me?


I have a set of scripts (bash, ruby, python) and want to put everything into a container like file so I can deploy this container on a lot of servers. This scripts need to protect from accessing other users (root included). So my idea was to create a encrypted container with all the sensitive scripts and mount this into RAM on boottime. But after mounting this container, the files are accessible from the system for everybody which has permission to it.  Is there some technique to deploy interpreted scripts (bash, ruby, ...) onto a system and nobody can see its content at any time? I don't want to run some "obfuscating" scripts.


grep - why do brackets in grep pattern remove the grep process from ps results?

Why do brackets in a grep pattern remove the grep process from ps results?  $ ps -ef | grep XXXX  [...] XXXX [...] grep XXXX   $ ps -ef | grep [X]XXX  [...] XXXX


I have a slightly unusual requirement for a custom resolution configuration in xorg.conf and need some help to figure out how to achieve it. I have a projector with 1400x1050 native resolution and want to use it in a poor man's Cinemascope mode @ 1400x584. The problem is I still need to feed the projector a full frame signal, while restricting X (or XBMC in this case) to only use a 1400x584 "slice", while outputting black/blank pixels above and below this. Ideally, I'd like to be able to define where the output "window" is positioned vertically within the 1400x1050 frame, but centered would be fine too. I'm pretty sure this should be possible but despite hours of searching I haven't been able to find any good answers - probably because most people aren't stupid enough to only want to use part of their screens... Any ideas?   Edit - These are the reported stats for the projector:   (II) NVIDIA(0): Frequency information for CAI CANON PJ (DFP-1): (II) NVIDIA(0):   HorizSync   : 15.000-80.000 kHz (II) NVIDIA(0):   VertRefresh : 50.000-85.000 Hz  (II) NVIDIA(GPU-0):   1400 x 1050 @ 60 Hz (II) NVIDIA(GPU-0):     Pixel Clock      : 108.000 MHz (II) NVIDIA(GPU-0):     HRes, HSyncStart : 1400, 1448 (II) NVIDIA(GPU-0):     HSyncEnd, HTotal : 1560, 1688 (II) NVIDIA(GPU-0):     VRes, VSyncStart : 1050, 1051 (II) NVIDIA(GPU-0):     VSyncEnd, VTotal : 1054, 1066 (II) NVIDIA(GPU-0):     H/V Polarity     : -/-   Another Edit - After more head-scratching, measuring and testing I've come up with a revised plan:   The projector has a motorized zoom, and what's more, it turns out that if I set the aspect ratio to 16:9 (on the projector) I am able to shift a 788px tall frame up/down within the 1050px tall viewport using the remote. Result! Combining that with the above, and with the help of the answers below, I think the best solution is to set the screen resolution in xorg.conf to 1400x788 (16:9) and use the zoom function to expand the projected image to the full height of the screen when viewing 2.39:1 (Cinemascope) content - thereby pushing the black bars off the screen and onto the masking. This solution has some major benefits:    When viewing 16:9 content I make use of nearly twice the number of pixels (1.1Mp vs. 600kp)  I gain the ability to adjust the vertical position of the image on the fly using the remote  A zoomed in picture is slightly brighter than the fully zoomed out one   The drawback is that to switch aspect ratios I now have to perform three steps: move the masking, zoom the picture and shift it into position vertically, as opposed to just moving the masking - but I can definitely live with that. The only question now is which of these two modelines to use:   Modeline "1400x788@69" 108.00 1400 1432 1840 1872 788 803 812 828 -hsync -vsync Modeline "1400x788@60" 89.66 1400 1432 1768 1800 788 804 812 828 -hsync -vsync   That is, should I go for maximum refresh (69Hz) or standard refresh (60Hz)?


How can one prove without using anything but differentiation, that $e^x$ is the only function with $f'=f$? Clearly I can prove that $(e^x)'=e^x$, and $0'=0$, but how can one show that no other functions exist? Thank you.


What is this icon that showed up on my android?

Any one has any idea what this notification icon means?   Thanks


Android Kotlin Dividing two Double type numbers yields an incorrect result with bad accuracy

Having a problem dividing two double number types. I'm after exact values so rounding is not really desirable. I have a UI field where data is pulled represented by the 'value' variable, and dividing it by another value to get an exact percentage. The first line is what I intend to use the rest the debug output I was experimenting with. The correct answer is 0.109* and I can only seem to get the correct answer when assigning the values directly and not from variable assignment. data.used = (value.text.toString().toDouble() / data.value) var n1: Double = value.text.toString().toDouble() var d1: Double = data.value var n: Double = 120.0 var d: Double = 1100.0 Log.d("TEST", "n1($n1)/d1($d1) = ${n1/d1} ") Log.d("TEST", "n1($n1)/d1($d1) = ${n1.div(d1)} ") Log.d("TEST", "n($n)/d($d) = ${n/d} ") Log.d("TEST", "n1($n1)/d($d) = ${n1/d} ")  This is the logcat output:  D/TEST: n1(120.0)/d1(1110.0) = 0.10810810810810811   D/TEST: n1(120.0)/d1(1110.0) = 0.10810810810810811   D/TEST: n(120.0)/d(1100.0) = 0.10909090909090909   D/TEST: n1(120.0)/d(1100.0) = 0.10909090909090909  It appears the value coming from the a class is the culprit. I cannot use the data.value member through reassignment or otherwise. Any idea why this is happening?


I have implemented a bubble sort for the linked list it swaps the whole nodes instead of values. I have debugged it many times and the sorting algorithm is working perfectly. but in the end, It does not update the head(starting) pointer of the linked list. If I return the first node of the list and assign it to the original one it is working fine. but what I need is when I give the starting node this function should sort the list and rearrange the nodes. main program  // implementations  details for the linked list     public static LinkedNode<Integer> linkedList=null;     public static LinkedNode<Integer> rear=null;      public static void main(String[] args) {         readValues("random10.txt");          // when I do like this it is not working         // new Sorting().bubbleSort(linkedList);          // if I do like this it is working fine         linkedList= new Sorting().bubbleSort(linkedList);          displayList();     }   sorting function public LinkedNode<Integer> bubbleSort(LinkedNode<Integer> first){          LinkedNode<Integer> i, j;         LinkedNode<Integer> previous;         LinkedNode<Integer> node_1;         LinkedNode<Integer> node_2;         previous = first;         boolean swapped=false;         for (i = first; i != null; i = i.next) {             swapped=false;             previous=first;             for (j = first; j.next != null; j = j.next) {                 if (j.getElement() > j.next.getElement()) {                     swapped=true;                     node_1 = j;                     node_2 = j.next;                                        System.out.printf("\nprevious = %d node1 = %d node2 = %d", previous.data, node_1.data, node_2.data);                      if (node_1.equals(previous)) {                         var temp=node_2.next;                         first=node_2;                         first.next=node_1;                         node_1.next=temp;                         i=first;                     } else {                         previous.next = node_2;                         node_1.next = node_2.next;                         node_2.next = node_1;                     }                     j=node_2;                                      }                 previous = j;             }             if (!swapped){                 break;             }         }         return first;     }


How do I put big brackets under different parts of an equation to attach text labels?

How do I put big brackets under different parts of an equation so that I can write, e.g., text specific to these parts? For example: f =  x^3 +  2     |___|  |__|        |     |    text 1  text 2


Android app's Achievements view doesn't show +2's from tag wiki edit approvals

I just noticed a bug in the Android app v1.0.51: reputation events from tag wiki edit suggestions aren't shown in the Achievements list on the Android app. This is from a HTC One running Android 4.4.3.  The following screenshots were taken within a minute of each other.  Website achievements list: some +2's        Android app: they don't show up


"can be clearly seen" OR "can clearly be seen"

In my essay the sentence      The results can be clearly seen.   was corrected to:      The results can clearly be seen.   What is the rule behind this correction?   Most of the time I use "can be" together without any words in between. Is that wrong?


addresses the question of how guests get into the park, but no one knows exactly where it is.  asks if Westworld is an isolated part of the country, while the one I am asking now provides evidence for being an island, on Earth, and asks where such an island may be.  So far, we have some information about the location of the park:   It borders an ocean, we have the size of the park based on a scale, and we have potential coordinates on the title bar:      It is an island:      From the Westworld Terms and Conditions:      INVESTIGATIONS/VIOLATIONS: If Delos, Inc. or any Delos Entity believes, in its sole discretion, that a violation of these Terms has occurred, it may take any and all corrective action it deems appropriate without notice, including contacting local authorities on the mainland. All human-on-human crimes taking place within the Delos Destinations compound will first be investigated by Delos, Inc.; Delos, Inc. has successfully avoided providing personal data in response to a legal process involving outside court entities for its entire history of existence. However, Delos, Inc. reserves the right to disclose personal information requested by a law enforcement agency, and shall have no liability to you for such disclosure.   Given the above information, and introducing more if you find it,   What is a plausible, existing island that matches the size of Westworld given by the map, as well as the ~coordinates given on the top bar? If there is not an existing island at around this location, where would this island to be, plausibly??


What command may I use to list the currently mounted filesystems on a Unix system?


Insert a value in array, show this array with this value

How to print the array with this value inserted? I need to show the initial array, the between array and the end array. public class ExercicioVetores {      /*      * Programa que recebe valores do usuário,       * 1 Valor do tamanho do vetor.       * 2 Valor da posiçao onde será inserido um dado       * 3 Valor á ser inserido na posição informada      * 4 Imprimir o vetor com o valor inserido na posição informada      * 5 Inserir todos os valores e mostrar o vetor completo.      */     public static void main(String[] args) {         // TODO Auto-generated method stub         System.out.println("Digite o TAMANHO do vetorBase que deseja criar.");          //Inicia o método que vai buscar as informações imputadas no System.in         Scanner teclado = new Scanner(System.in);          // Criando vetor com parametro recebido.         int vetorBase[] = new int[teclado.nextInt()];         // Iniciando vetor com valores zarados         Arrays.fill(vetorBase, 0);          System.out.println("O vetorBase tem TAMANHO = " + vetorBase.length);          //Mostrando os valores do vetor criado         for (int i : vetorBase) {             System.out.printf(" " + vetorBase[i]);         }         System.out.println("");          System.out.println("Digite a POSIÇÃO que deseja inserir um VALOR.");         int posicaoValor = teclado.nextInt();          System.out.println("Digite o VALOR que deseja inserir na POSIÇÃO.");         int valorInserido = teclado.nextInt();          System.out.println("Será inserido no vetorBase de TAMANHO = " + vetorBase.length + ", na POSIÇÃO = "+ posicaoValor + ", o VALOR = " + valorInserido);         vetorBase[posicaoValor] = valorInserido; //Vetor Base na posicaoValor recebe o valorInserido.  //Imprimir o vetor criado para mostrar a posição que foi inserido o valor na posição correta. //On this point i like to print the array with the value inserted.          for (int i : vetorBase) {             System.out.println("");         }                                             /*          * Arrays.sort(vetorBase); Ordenação do vetor int mostrarPosicao =          * Arrays.binarySearch(num,1); Buscar valor          */      }// main  }// class


Would there be any gravity inside a hollow planet made of a spherical shell of basalt crust?

I am writing a science-fiction story, which contains a 'crazy' planet. I would like some input into the consequences of this physics according to standard physics. The planet in question is Earth-sized and it orbits a Sun-like star. Within the story, this planet has been taken over by a malignant 'force' and has been hollowed out, so that there is one mile of basalt crust forming a spherical shell, and the inside is a void filled with nitrogen. This force keeps the planet intact, but does not affect the planet in any other way (i.e. any standard-physics problems regarding the integrity of this spherical shell can be ignored, as the story explains them in other ways). The force has no mass. Given this setup, what would the gravity be like at the center of the planet? In the story, the protagonist is able to fly around in a large bubble of zero-gravity at the middle. Would this be possible? (Assume that the protagonist can survive the atmosphere.) Could he, assuming he has a suitable raft, get around by blowing?


Including a complex Matplotlib.Pytplot figure in Latex

I'm not sure if I should post this on the Python SE or here. I have made a complex figure in Python that is exactly how I want it to be. Now I want to include that figure in my thesis in LaTeX. As of now I am taking a screenshot of the figure and including it in LaTeX like so:  \begin{figure}[h]     \centering     \includegraphics[width=1\textwidth]{pythonfigure.png}     \caption{The most accurate (top) and least accurate (bottom) transposition pathways}     \label{fig:pythonfigure.png} \end{figure}   This makes the figure quite fuzzy and low quality:   Is there a way to transfer the figure from Python to LaTeX and still keep the crispness in LaTeX?  My Python code for the figure is as follows:  def mod_meas_subplots(x, y1, label_a, label1b, ax1_title, y2, label2b, ax2_title, y3, label3b, ax3_title, y4, label4b, ax4_title,  graph_xlabel, graph_ylabel, windowtitle): """This function plots a figure containing four subplots of modelled vs measured irradiance.""" fig, ((ax1, ax2), (ax3, ax4)) = plt.subplots(2,2)   fig.canvas.set_window_title(windowtitle) ax1.scatter(x, y1, marker = 'o', label = label1b, alpha = 0.30) ax1.plot(range(0,1100), range(0,1100), 'r', label = label_a) ax1.set_ylabel(graph_ylabel) ax1.set_title(ax1_title) ax1.set(adjustable='box-forced', aspect='equal') ax1.set_xlim(0,1100) ax1.set_ylim(0,1100) ax1.legend(loc = 2) ax1.grid(True)  ax2.scatter(x, y2, marker = 'o', label = label2b, alpha = 0.30) ax2.plot(range(0,1100), range(0,1100), 'r', label = label_a) ax2.tick_params(axis = 'y', left = 'off', labelleft ='off') ax2.set_title(ax2_title) ax2.set(adjustable='box-forced', aspect='equal') ax2.set_xlim(0,1100) ax2.set_ylim(0,1100) ax2.legend(loc = 2) ax2.grid(True)  ax3.scatter(x, y3, marker = 'o', label = label3b, alpha = 0.30)  ax3.plot(range(0,1100), range(0,1100), 'r', label = label_a) ax3.set_xlabel(graph_xlabel) ax3.set_ylabel(graph_ylabel) ax3.set_title(ax3_title) ax3.set(adjustable='box-forced', aspect='equal') ax3.set_xlim(0,1100) ax3.set_ylim(0,1100) ax3.legend(loc = 2) ax3.grid(True)  ax4.scatter(x, y4, marker = 'o', label = label4b, alpha = 0.30) ax4.plot(range(0,1100), range(0,1100), 'r', label = label_a) ax4.tick_params(axis = 'y', left = 'off', labelleft ='off') ax4.set_xlabel(graph_xlabel) ax4.set_title(ax4_title) ax4.set(adjustable='box-forced', aspect='equal') ax4.set_xlim(0,1100) ax4.set_ylim(0,1100) ax4.legend(loc = 2) ax4.grid(True)  fig.tight_layout   plt.show()   And then calling the graph function with the right parameters:  mod_meas_subplots(df.G_POA_S_15, POAdirint_11.poa_global, 'Ideal line','MAE = ' +str(round(MAE_POAdirint_11, 2)), 'DIRINT and Perez: Phoenix 1988',                     POAdirint_14.poa_global, 'MAE = ' +str(round(MAE_POAdirint_14, 2)), 'DIRINT and Perez: Albuquerque 1988',                    POAerbs_14.poa_global, 'MAE = ' +str(round(MAE_POAerbs_14, 2)), 'Erbs and Perez: Albuquerque 1988',                    POAerbs_13.poa_global, 'MAE = ' +str(round(MAE_POAerbs_13, 2)), 'Erbs and Perez: Ossage 1988',                    'Measured POA irradiance ($W/m^2$)', 'Modelled POA irradiance ($W/m^2$)', 'POA models with lowest and highest MAE')


Sequence according to value from table in postgresql

I have dictionary_type and dictionary_value tables. Value is connected with type. I would like to create sequence which will set the id of values according to type id.   Expected dictionary_type:   id       type      ----     ----  1        type1        2        type2              Expected dictionary_value:   id       type_id     value -------  -------  ------- 100      1         value1 200      2         value2 101      1         value3 102      1         value4 201      2         value5   So baiscly I would like to make it like: nextval(sequence(type_id * 100)). How can I do it in postgresql?  Have a nice day!


Does there exist an infinite field with characteristic $p$ for any prime $p$ that is not too big?

Does there exist an infinite field with characteristic $p$ for any prime $p$?  I haven't seen any such fields in my course yet.


How to run untrusted Ruby code inside a safe sandbox?

I want to be able to run unstrusted ruby code. I want to be able to pass variables to said untrusted code that it may use. I also want said code to return a result to me. Here is a conceptual example of what I am thinking  input = "sweet" output = nil Thread.start {    $SAFE = 4    #... untrusted code goes here, it uses the input variable(s)    #to calculate some result that it places in the output variable } #parse the output variable as a string.   Just to clarify, I am basically using the untrusted code as a function. I want to  provide its some inputs, and then allow it to write to the output. That is all I really want, I don't care how it is done, I just want the ability to use untrusted Ruby code as a sort of function. The solution does not have to look anything like the code I wrote above, I am just using it to illustrate what I want.  Now, I can currently think of 3 ways to do this:   Use the $SAFE level construct above. whytheluckystiff has a Sandbox plugin for ruby I could run each function in its own virtual machine, using some sort of os virtualization software like vmware or Xen or something.   I am wondering if anyone has any recommendations for running untrusted ruby code in a functional way? What option would you recomend? How would you go about it? Thanks.


I'm following this tutorial () to add a new systemd .service, but it doesn't work, I did step by step correct with some modifications to my scope. My conkystart.service:  [Unit] Description=Service to start conky at boot After=graphical.target multi-user.target  [Service] Type=simple ExecStart=/usr/local/bin/conkystart.service  [Install] WantedBy=multi-user.target  My simple script:  !#/bin/bash  sleep && conky;  Nothing it does'nt work. Some advice guys? What's wrong here?


Add tools and background sections to Careers PDF export

Your Careers 2.0 profile has two 'special interests' sections:    Unfortunately, these are not included in the PDF export, not even as an option. Could these be added?


I'm getting black artifacts in my renders. It looks like black pepper.  I've already re-calculated the normals (they were already facing in the right direction, anyway). You can see the artifacts on the door and the awning:    I'm using v2.68, but I get the same thing in v2.70.


Compute $\sum\frac1{2-A_k}$ for $(A_k)$ the $n$th roots of unity


how to divide one window into two windows

I'm having difficulty dividing a window into two parts vertically. I know how to divide it horizontally but I cannot do it vertically.  What difference is there between the two?


Windows 10 Search can't find ANY applications. Even calculator

I have problem with Windows 10 Enterprise N x64. When I press "Start" and start to type application name it never finds it.  I can't even find applications like "Calculator", "Microsoft Word" or any other. Just moving dots and I let it run for 30 minutes without any success.  PS. There is chance that this will not work for you if you did upgrade instead of clean install of Windows 10. But you can always try.  This are my indexing options.


How do you format the date time to just date?   For example, this is what I retrieved from the database: 12/31/2008 12:00:00 AM, but I just want to show the date and no time.


I'm sure there is already such a question, but after searching I didn't find anything.  I'm looking for the method that would make \sim stretch depending on the text above.  Here is the example of what I need.


python list assigning to multiple variable with or without an multiple operator gets different result?

when I try to assign a list to 2 variables, the following 2 ways get different results? # way1 a,b =  [[None,None],[None,None]] # way2 c,d = [[None,None]]*2   a and b have different addresses on memory caches, while c and d have the same one. print(id(a),id(b)) # out: 5243249856 5243249472  print(id(c),id(d)) # out: 5243246016 5243246016  The right-side lists are completely the same, the only difference is the way to create the list (way2 uses a '*' to expand the list). However, the left-side get different results. How is this happen? any one have any idea?


Latex markup removal script (delcmdchanges.bash) not working

I have used changes package in my latex source code. To accept changes I can use final in tex file in order to remove tags in the output (PDF). If I need to remove markup in latex source,  script is avaliable but the output is alike input, It doesn't remove markup in the latex.  I tried, sudo sh delcmdchanges.bash input.tex output.tex  Example:  \documentclass{article} \usepackage{changes} \begin{document} \centerline{\sc \large A Simple Sample \LaTeX\ File} \vspace{.5pc} \centerline{\sc Stupid Stuff I Wish Someone Had Told Me Four Years Ago} \centerline{\it (Read the .tex file along with this or it won't              make much sense)} \vspace{2pc} The first thing to realize about \LaTeX\ is that it is not ``WYSIWYG''.  In other words, it isn't a \added{some text} word processor;  \end{document}


Prove that $x^x+y^y=z^z$ doesn't have integer solutions  To be honest, I don't see any way to start this problem, I tried for hours but it's not as easy as I thought.  Any hints?  As you can see in the comments, there is a solution for natural numbers, the problem is when the set is extended to integers solutions.  *This is a problem for a national olympiad in my country, this olympiad usually puts all the solutions but i didn't found a solution for this problem in the page, i don't know why.  Possible answer:  Property:   Be $A,B,C$ $\in \Bbb R$ $\ne 0$ such that $A+B=C$. Then exist $U,V \in {A,B,C}$ such that:  $$2|U| \gt 2|V| \ge |U|$$  Proof: Write $C'=-C$, then $A+B+C'=0$. The numbers $A,B,C \ne 0$ by hypothesis, and they can't be the three of the same sign because then they can't add $0$, so there are two of the numbers $A, B, C'$ that have the same sign and the other has a different sign.  Amplifying the equality $A+B+C'= 0$ $\,$ by $-1$ if its necessary, we can assume that there are two of them (which we will call $X,Y$) that are positive and the third negative (we will call it $-Z$, with $Z\gt 0$). Then we have $Z=X+Y$ with $X,Y,Z \gt 0$ and that $X,Y,Z$ are equal to $|A|, |B| , |C|$ in some order.  WLOG we can assume that $X\le Y$ , then:  $$Z=X+Y\le 2Y \lt 2Y+2X = 2Z$$  Obtaining $2Z \gt 2Y \ge Z$ as we wanted.  Solution: Assume that  $$(1): \; x^x+y^y=z^z$$  has integer solutions $\ne 0$, let $(x,y,z) = (a,b,c)$. According to the property, there exists integers $\ne 0$ $(u,v) \in (a,b,c)$ such that $2|u^u| \gt 2|v^v| \ge |u^u|$. Dividing by 2 and taking $\log$ we see that there are non-zero integers $(u,v)$ such that: $$u\log |u| \gt v\log |v| \ge u\log |u| - \log 2$$ That can be written as: $$(2): \;0 \lt u\log |u| - v\log |v| \le \log 2$$  The inequality (2) says that $u\log|u| \gt 0$ or $v\log|v| \lt 0$, but if $v \log |v| \lt 0$ then: $$u \log |u| - v \log |v| = (-v)\log|-v|\;-\;(-u)\log |-u|$$ with $(-v)\log|-v| \gt 0$, so unless we make a substitution, we can assume that $u \log |u| \gt 0$. In this case, necessarily $u \ge 2$, so   the second inequality of (2) says that: $$v \log |v| \ge u \log |u| - \log 2 \ge 2 \log 2 - \log 2 \gt 0$$  Matching this with the first equality of (2) we get: $$ log 2 \ge u \log |u| - v \log |v| \gt (v+1)\log |v| - v\log|v| = \log|v| \ge \log2$$ a contradiction. Thus $x^x+y^y=z^z$ doesn't have any integers solution.


Why is there no function with a nonempty domain and an empty range?

Let $A$ to be a nonempty set and $B= \emptyset$; then $ A \times B$ is a set. And let $F$ be a function $A \to B$. Then $F \subseteq A \times B$. By the axiom of specification, $F$ must exists (if I didn't mess up something).   But the book I'm reading, Elements of Set Theory by Enderton, says that no function could have a nonempty domain and an empty range, and no more detail is given.  So my confusion arises. His statement against my proof. The only axiom as far as I know to prove such a set does not exist is the axiom of regularity. But I can't give such a proof. So I need help. I hope someone could clearly explain why such a function doesn't exist, and why this doesn't contradict the axiom of specification.    Let me explain my confusion in more detail:  First of all, I know that $A \times \emptyset$ is empty. But $ \emptyset \times A$ is also an empty set, yet there is no problem with functions with an empty domain.  The book I'm reading defines a function as:      "A function is a relation such that for each $x$ in $\operatorname{dom} F$ there is only one $y$ such that $x \mathop F y$."   and a relation as:     "A relation is a set of ordered pairs."   Now, let me define the function $F$ as: $$F =  \{\langle x,y \rangle \mid x \in A \text{ and } y \in B \text{ and ... other conditions} \}$$  so it's equal to: $$F = \{ \langle x,y \rangle \in A \times B \mid \text{... other conditions} \}.$$  Doesn't that mean that $F$ meets the conditions of the axiom of specification, and therefore exists?    What I would specifically like to ask is:   How do you define a function $F$ (as precisely as possible)? Why does the argument above not imply that a function $F: A \to B$ always exists? Does $F \subseteq A \times B$ still hold when $B = \emptyset$?   (The answer to #2 cannot simply be that $A \times B = \emptyset$, because $ B \times A = \emptyset$ as well, but a function $B \to A$ does exist.)


Change system language from Russian to English in Vista

When I went over to Russia, my host family bought me a laptop as a farewell present. It was all fine and dandy, but I really did prefer it if the language of the Start Menu and all other components was in English.  I am not sure if the OEM version of Windows Vista includes the English language UI, if I will need  to download and/or purchase a 'language pack', or if I will have to buy a brand new copy of Vista in English.  How can I change the system language in Windows Vista to English? Is there anything else I would need to purchase?


What does"Questions with most views, answers and votes" mean? I just don't get it, how does SE arrange questions with hotness? It does not seem to arrange questions with the most views or votes.


Will I need any Malaysian Rinngit at Kuala Lumpur airport when I'm leaving the country?

I'm about to leave Malaysia and expect to get a much better rate for my Ringgit here in Chinatown than at the airport.  So after having paid for my plane ticket and transportation to the airport, are there going to be any surprise fees or costs between getting to the airport and departing?  (In other countries over the years there have been things such as departure taxes and airport improvement taxes that I was not expecting.)


Is there any site that shows me what are older packages which are replaced by newer ones?

Currentyl I am using a template from our university which is from 2010. I added some packages etc. but now I am not sure if there are "duplicates" of packages I am using.  For example I have   \usepackage{xcolor}  \usepackage{color}  \usepackage{graphicx}   Where I would say {color} is not needed any longer? There are some more packages where I cannot say if there are newer ones which replaces them. So is there some ressource where stand something like:  color -> xcolor (xcolor provide the same as colour and add features)  Or may even a discrete package which test my code if there are "old" packages or if I have some compability issues?


How can I sync the new "people" (face recognition) metadata across devices in Photos (iOS 10 and MacOS Sierra)?

The new Photos updates for iOS 10 and MacOS Sierra includes a much more powerful and integrated approach to organizing photos by who's in them.  It's built around powerful, on-device facial recognition.  But once it does its automated thing (finding the faces it thinks are the same person), there's still a lot of manual merging and labeling to be done if you have a lot of photos and are as obsessive about organization as I am.  For example, if you have, say... three thousand photos of your daughter, Photos will find almost all of them, but may guess they're 5 or 6 different people.  So you have to merge the buckets that all are one person, assign them a name (so you can search by it), etc.  But unlike other changes (edits, deletions, organization into albums, etc.), manual changes to "people" data don't seem to sync at all by default.      Is there really no way to do this?  It seems bizarre that one of the flagship features Apple's touting in this Photos update doesn't play at all with what was Photos primary selling point over iPhoto - everything synced on all your devices.


I have a new Sony E Series Vaio with an intel i5 and an AMD 7xxx mobile card. Despite making sure sure my app (game) is set to High Performance in switchable gfx and choosing high performance power plan I'm not entirely convinced the gfx card is being used over the CPU's HD4000 chipset. Is there anyway I can prove for sure the AMD card is being used?  thanks for reading  (OS is Win8 64bit)


How do I interpret the results from the F-test in excel

I have a fairly simple question regarding the interpretation of the F-test in Microsoft Excel.  Let't say these are the results of my F-test:    I am now wondering how to interpret it in order to choose the correct t-test (assuming equal or unequal variances) for my data-set.  I have found guides telling me if F critical > F, then use unequal variances. However, some of the guides tell you to use only the p value, so I am unsure which parameters to look at when interpreting the results.


TexMaker refuse to compile with Error : could not start the command : "/usr/texbin/pdflatex" -synctex=1 -interaction=nonstopmode  I have read that same happened after installation of El Capitan, but I have installed the last Mac update Sierra. I have tried to reinstall MacTex, but it didn't help.  In the settings it is offering me to choose between version 2013 and 2016 but I can't choose neither of them, it is failing with "Setting up the /usr/texbin link"    Please help.  Nelya


I am programing a neural network from scratch in C++ (purely for fun).  My dataset is cut in 3 : 1 train, 1 validation for early stopping and 1 test to measure model accuracy.  I measure accuracy output by output by checking if the obtained result is between a relative range around the expected output. Is that the right way to do ? If the expected value is 0, then the range between 0 is always 0. I dont want to use absolute range because it is scale dependant. How could i do ?  Thanks.


My friend asked the following question related to matrices:  Assume A is   $$     \begin{pmatrix}     \frac{1}{2} & 0 & \frac{1}{2} \\     1 & 0 & 0 \\     0 & \frac{1}{2} & \frac{1}{2} \\     \end{pmatrix} $$  and B is   $$     \begin{pmatrix}     \frac{1}{4} & \frac{1}{4} & \frac{1}{2} \\     \frac{1}{2} & 0 & \frac{1}{2} \\     \frac{1}{2} & \frac{1}{4} & \frac{1}{4} \\     \end{pmatrix} $$  AB = BA =$$     \begin{pmatrix}     \frac{3}{8} & \frac{1}{4} & \frac{3}{8} \\     \frac{1}{4} & \frac{1}{4} & \frac{1}{2} \\     \frac{1}{2} & \frac{1}{8} & \frac{3}{8} \\     \end{pmatrix} $$  Why is this true? From the knowledge that I have, $A, B$, and the product are not identity matrices.  $A=B^{n}$ is not true.


Increase /home partition with unallocated space

I would like to increase my /home partition but I can't find right manipulation to do it (I know I need to use gparted live cd) but when I try yo extend the /home partition, there is no disk space available.   Can someone help me and tell me the right manipulation to increase the /home partition ?


How do you detach the 2nd screen from within another screen?

I've accidentally attached to a 2nd GNU screen session from within an existing screen session and cannot detach or issue commands to the inner screen. I remember figuring out how to do that before but completely forgot and would like to keep it as reference.  One way is to detach the inner screen by doing screen -dr from shell, but what is the key combination to do that from within screen itself?


Voting to close a question from the flag queue cause "undefined more votes needed" to appear when the question is closed

I found  in the flag queue, and I voted to close it. As you see, I am the last one who voted to close it.  After I did it, the flag queue showed the following.        It should have shown the question was closed, but "undefined more votes needed" is what appears between brackets.


Can you freeze liquids to pass security checks?

Once I read a suggestion saying that frozen "liquids" are not subject to the 100 ml restriction of security checks in airports. I've found   of this googling, but they all refer to TSA (I assume only hold in the US).  Is it true then that it's possible to carry frozen fluids in your hand luggage, in larger quantities than 100 ml?


How do I set a vertex color material in Blender 2.8?

I have a model with vertex colors in it. I would like to display it in rendered shading. There is no more an input called vertex color.  I'm using Blender -2.80-387c1f2e0d5d-linux-glibc224-x86_64  How should I proceed?


Find a circle's radius with three known tangent lines

I need to find the equation for a circle (mainly its radius) which is tangent to the following three lines:  $y = 0$  $y = \tan(70)x$  $y = -1.428148x + 0.790201$  For the last tangent line equation, I know that it is tangent at the point $(0.371272, 0.259968)$ However, for the other two I do not know the exact point of tangency, only that the circle is tangent to them.


How to render an animation made with a python Script

I have a simpĺe python script that triggers an animation base on the location of a cube. import bpy  scene = bpy.context.scene obj = scene.objects['Text']  def recalculate_text(scene):     x = scene.objects['Cube'].location[0]     obj.data.body = '{0:.1f}'.format(x)  bpy.app.handlers.frame_change_pre.append(recalculate_text)  Using a text Object it shows the location of the cube in the Viewport. The problem is that because my python skills are very basic, i can't Render the animation; once i hit "Render animation" ( Itried: EEVEE and CYCLES: Image sequence and video) it only shows the first frame of the text object.


After installing binary to another directory, error "No such file or directory"

After uninstalling a program with apt and reinstalling it in another location (ex. pypy with snap), running the program from command line reports bash: /usr/bin/pypy: No such file or directory, but which pypy correctly gives /snap/bin/pypy. How do I get the shell to recognize the new installation location?


@future method fired from trigger - order of execution

Quick introduction:   I Approve one of many approval levels on my custom object the before update trigger is fired I'm searching for the approver comments but nothing's there yet (operations are not commited yet)   I would like to send the approver comments via email with before update or after update trigger (I cannot use email alert because of some complexities).  What I noticed is that when I'm trying to execute the @future method (from within the trigger handler class) that's searching for approver comments, it always works fine, I can find and send the newest comment.  As documentation states:     Each future method is queued and executes when system resources become available.   Maybe the fact that the @future method always runs after the trigger is just an accident but I'm wondering if there's some sneaky logic under the hood like (i.e) the resources become available always after the trigers' cycles, and not earlier. Is there? Or can I rely on this behavior?


how do me and my friend play minecraft on pc together on my or her world?

me and my friend wants to play Minecraft together on my or her world but we don't know how, we live in different buildings and she cant come over, she has a ps4 with Minecraft and i play Minecraft on a pc.


How to prove that $\lim\limits_{x\to0}\frac{\sin x}x=1$?

How can one prove the statement $$\lim_{x\to 0}\frac{\sin x}x=1$$ without using the Taylor series of $\sin$, $\cos$ and $\tan$? Best would be a geometrical solution.  This is homework. In my math class, we are about to prove that $\sin$ is continuous. We found out, that proving the above statement is enough for proving the continuity of $\sin$, but I can't find out how. Any help is appreciated.


Is it possible to use `\substack` with `\textnormal` in an `align*` environment?

I am trying to write multiple lines underneath my minimisation problem in an align* environment. This can be achieved by using the command \min_{\substack{x_{j} \\ j=1,...,70}}, which produces the following output  I would like to write minimisation, as opposed to min. However, the command \textnormal{minimise}_{\substack{x_{j} \\ j=1,...,70}} does not produce the required output. How can this be achieved?


I would like to downgrade my Nexus One to 2.2.2, because I've had non-stop problems with Gingerbread. I have the 2.2.2 update from , and going off the , I'm under the assumption that this is doable.  So I've gone through the Bootloader -> Recovery -> apply sdcard:update.zip steps, and it fails with the following message:  assert failed: file_getprop("/system/build.prop", "ro.build.fingerprint") == "google/passion/passion/mahimahi:2.2.1/FRG83D/75603:user/release-keys" || file_getprop("/system/build.prop", "ro.build.fingerprint") == "google/passion/passion/mahimahi:2.2.2/FRG83D/91102:user/release-keys"  E:Error in /tmp/sideload/package.zip (Status 7) Installation aborted.   I would guess the OS is checking if I'm on either 2.2.1 (updating from the previous version) or 2.2.2 (reinstalling the target version), is this assumption correct?  This begs the question, how do I go from 2.3.6 to 2.2.2? Do I need to factory reset, and apply updates sequentially?


When does a search engine learn about a particular user inside a website and display the profile link and /or a Login link along with search results?

How does Google search engine display user profiles or Login links along with a search results of some websites? because obviously the username or profile name is coming from the server side, so does Google search engine go into the website Database (i.e. Facebook database) and retrieve the link for a particular user?  is that something the website developer have to work on on his end or is this determined by the website popularity by Google itself?  To illustrate my point, photos below are an example:  This is what you get when you type "facebook" on Google search:    And This is what you get when you type "CNN facebook" on Google search:


This is a follow-up question to .  The numbers printed by \num[group-separator={,},group-minimum-digits=4]{\the\numexpr(5000)\relax} will produce comma separated numbers in groups of three digits each.  In India, however, we group numbers differently. Ones, Tens and Hundreds is the only group of three digits. All other groups are of two digits each.  The following example illustrates the difference:   123,456 gets written as 1,23,456 1,234,567 gets written as 12,34,567 12,345,678 gets written as 1,23,45,678 123,456,789 gets written as 12,34,56,789   Is there any way to get latex to format the numbers Indian way?


Generalization of Brouwer Fixed Point Theorem for infinite disk

I was thinking about Brower's fixed point theorem. Every continuous function $f:D^n\rightarrow D^n$ has a fixed point where $D^n$ is the closed unit ball in $\mathbb{R}^n$. I started thinking of a generalization. If we consider $D^\infty\subseteq\ell^2$ where $D^\infty=\{(x_0,x_1,...)\vert\sum_{i=0}^\infty x_i^2\leq 1\}$. Must it be true that every continuous function $f:D^\infty\rightarrow D^\infty$ contains a fixed point. When looking for an answer, I discovered the Schauder fixed point theorem, but I am not sure if it is applicable here (I am primarily worried about the condition that requires $f(D^\infty)$ to be contained in a compact subset of $D^\infty$).  My intuition tells me that such a function with no fixed points exists; however, it isn't clear why. If someone knows of such a function with no fixed points, or of a proof of why no such function exists, I would be interested to learn.


I just did an install of the hp laserjet P1102w printer and it's not working. I'm using Ubuntu 12.04, and I went to see if I had hplip installed and it said I did.  How do I set up this printer?


I was approved for an immigrant visa and later deny me before picking up my visa at the US embassy after a few days of my interview, cause they found out that from my previous interview (2005) 4 years before the recent one in(2009), that my information was mixed up on my passport. Eg, My name on my old passport had John Olamide Obie and the new one had John Seun Obie, But my full name is John Seun Olamide Obie on my birth certificate. The reason why i had issues with that was that we are only allowed to put 3 names on our passport. Plus old passport had 30 January 1985( Agent made mistake with my passport application) and my real birthday is 30 January 1979.  I have been giving the offer to study in Canada, but I don't know if that would affect my Canadian immigration application, since I had issues with the Us embassy in Nov 2009.  My understanding is based on the section that says:  In general: Any alien who, by fraud or willfully misrepresenting a material fact, seeks to procure (or has sought to procure or has procured) a visa, other documentation, or admission into the United States or other benefit provided under this Act is inadmissible.  Does that affect North American countries, since they share databased?  Thank You.


Does using "new" on a struct allocate it on the heap or stack?

When you create an instance of a class with the new operator, memory gets allocated on the heap. When you create an instance of a struct with the new operator where does the memory get allocated, on the heap or on the stack ?


Find all relatively prime successive binomial coefficients

Find all couples $(n,k)$ , $n \geq 2$ and  $0\leq $ k $ \leq n - 1$, such as : $\binom nk$ and $\binom {n}{k+1}$ are relatively prime. I first tried finding a link between the two using combinatorics, but it wasn't that easy, since they don't have a particular order, and any could be greater than the other. Then I recalled that if $n$ is prime, it's guaranteed that it divides both of them, I tried to apply this in a more general scenario, using a prime divisor of $n$, but it didn't succeed. Any ideas or tips?


How to calculate the distance between two points with realtime firebase database, and also display the current distance he is travelling?

I am trying to Develop a Vehicle Tracking app where I want to track Drivers activity Like DISTANCE, TIME TAKEN , AVRAGE SPEED. I am able to Track his current location and also see the path the Driver is going on in firebase database, Now I have found a code from a project for Distance, I have implemented it in my project.and the app is crashing, is there a different way to get and calculate distance, stopwatch, speed?? public void newJourney(){     locations = new ArrayList<Location>(); }  public float getDistanceOfJourney(){     if (locations.size() <=1){         return 0;     }      return locations.get(0).distanceTo(locations.get(locations.size() - 1)) / 1000;  }   protected void onStart() {     super.onStart();     if (ContextCompat.checkSelfPermission(this,Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED)     {         startLocationUpdates();     }     initButtons();     /////////NEW ///////////////////////     new Thread(new Runnable() {         @Override         public void run() {             float d = (float) getDuration();             long duration = (long) d; // in seconds             float distance = getDistanceOfJourney();              long hours = duration / 3600;             long minutes = (duration % 3600) / 60;             long seconds = duration % 60;              float avgSpeed = 0;             if(d != 0){              //   avgSpeed = distance / (d / 3600);             }              final String time = String.format("%02d:%02d:%02d", hours, minutes, seconds);             final String dist = String.format("%.2f KM", distance);             final String avgs = String.format("%.2f KM/H", avgSpeed);              postBack.post(new Runnable() {                 @Override                 public void run() {                     durationText.setText(time);                     avgSpeedText.setText(avgs);                    distanceText.setText(dist);                 }             });             try {                Thread.sleep(500);             } catch (Exception e){                e.printStackTrace();;            }         }     }).start(); }  after running this code am getting this error in log java.lang.NullPointerException: Attempt to invoke virtual method 'int java.util.ArrayList.size()' on a null object reference     at com.example.vehicletracker.MapsActivity.getDistanceOfJourney(MapsActivity.java:116)     at com.example.vehicletracker.MapsActivity$3.run(MapsActivity.java:293)     at java.lang.Thread.run(Thread.java:923)  Below is the Code of tracking the current Activity and updating it in realtime:  @Override public void onLocationChanged(@NonNull Location location) {      if (location != null) { //location is enabled         saveLocation(location);      } else { //When user has no access to location         Toast.makeText(this, "No Location", Toast.LENGTH_LONG).show();     }      //polylines     double latitude = location.getLatitude();     double longitude = location.getLongitude();     LatLng latLng = new LatLng(latitude, longitude);      polypoints.add(latLng);     redrawLine();      //newUpdate     if (recordLocations){         locations.add(location);     } }  private void saveLocation(Location location) {     databaseReference.setValue(location); //Saving Location of user To db }


What is the difference between a relative phase and a global phase? In particular, what is a phase?

I know that $re^{i\theta} = x + iy$ for any complex number $x + iy$ by Euler's formula. How do you calculate relative and global phase?


How does a knife cut things at the atomic level?

As the title says. It is common sense that sharp things cut, but how do they work at the atomical level?


Parameter numbering doesn't work in a \newenvironment footer. How to make it work?

I try to create a new environment for a monotonously repeating tabular, which has one parameter. This must be at the end of the tabular. I tried this way:  \documentclass[12pt]{article} \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage[magyar]{babel} \usepackage{amsthm} \newenvironment{point}[1] {     \begin{tabular}{ @{}p{.4\textwidth}p{.4\textwidth}c@{} }     \hline } {     \hline     \multicolumn{2}{r}{Summary}& #1 point     \end{tabular} }   but I got Illegal parameter number in definition of \endpoint. error. I can't figure out, why is it happen and how to solve it.


have ubuntu 14.04 LTS have used libre office for a while just stopped opening one day. gives an error message stating has experienced an internal error. Have tried uninstalling libre office and reinstalling. Have downloaded direct from libre office and reinstalled still no luck.


How to resize an image through the terminal?

I have Ubuntu 10.04. I have converted image through terminal using the following command:  convert myfigure.png myfigure.jpg   But I want to resize the height and width of the converted image. Is there any way to do this?


Every set with more than point admits a permutation with no fixed point and the Axiom of Choice

Assuming axiom of choice , for any set  $S$ with more than one point , there exist a bijection $f:S \to S$ such that $f(s) \ne s , \forall s \in S$ . Is the converse true , i.e. Does the statement " For every  set  $S$ with more than one point , there exist a bijection $f:S \to S$ such that $f(s) \ne s , \forall s \in S$ " implies Axiom of Choice ? Or at least  can we prove that  any set with more than point has a permutation with no fixed point , without axiom of choice ? Please help. Thanks in advance


How to get Discord 0.0.2 to work on Ubuntu 16.04?

Today I was unable to open Discord without updating it to the 0.0.2 version. I attempted to install it using the .deb file but when clicking on "install", nothing happened. So I installed it using the .tar.gz file with these commands:  sudo ln -s /usr/share/discord/discord.desktop /usr/share/applications/ sudo ln -s /usr/share/discord/discord.png /usr/share/icons/ sudo ln -s /usr/share/discord/Discord /usr/bin/discord   When I opened the application I just got a blank screen:


I can't see usb-drives and archives in the sidebar of the finder anymore

When I plugin a usb-drive or open dmg-archives they don't appear under the 'Devices' section in the sidebar of the Finder anymore.  The drives are there when I check with 'Disk Utility', they appear on the Desktop and I can browse the files if I go to /Volumes.  I have 'Hard disks' and 'External disks' checked in the Finder preferences -> Sidebar tab.  Any ideas on how to get them to show up in the sidebar?  I'm using MacOS Lion 10.7.5.


How do I make a tab on a tabcontrol disappear?

I want to make a all of the tabs on a tabcontrol disappear/not be visible once a button is pressed. I've been trying some things, but they haven't worked out.  If someone could help me figure out how to do this, that'd be great.  This is in a regular C# project (made with forms).


Whats wrong with this proof? (infinite sequences)

So I just watched a video where they explained that the sum of all natural numbers is $-1/12$. However, there was an interesting comment:  S1 = 1 + 2 + 3 + 4 + 5 ... = - 1/12 S1 - S1 =          1 + 2 + 3 + 4 + 5 + 6 ...              - 1  - 2  - 3 -  4 -  5 ... =      1 + 1 + 1 + 1 + 1 + 1 ... Since S1 - S1 = - 1/12 - (- 1/12) = 0 It follows that 1 + 1 + 1 + 1 + 1 .... = 0 Let's name this sequence S2: S2 = 1 + 1 + 1 + 1 + 1 ... = 0 Now let's subtract it from itself: S2 - S2 =          1 + 1 + 1 + 1 + 1 ...              - 1  - 1  - 1  - 1 .... =      1 Given that S2 equals 0, we can also write this as: 0 - 0 = 1   For those who are wondering about the video:  It does the same trick of "shifting". With infinity and stuff things get tricky. What is wrong with this proof? I am a math student, so involved answers with limits is fine.


There is a statement in my physics textbook in gravitation chapter - The force of attraction due to hollow spherical shell of uniform density on a point mass situated inside it is zero Is it valid for solid sphere? What happens in solid sphere? Please explain this statement.


Is the word "acronym", in fact, clearly defined?

I was about to ask the following question:  “Is 'CIA' an acronym, or is only 'laser' an acronym?”  Now, in another question, I've been asking about the earliest use of words which started as initials but which are pronounced as words (which excludes "CIA"). For clarity's sake, I was wondering about the case of “laser” and not the “CIA” one. In the course of that discussion, naturally the word "acronym" appeared: I became interested in the meaning of the word "acronym."  Does "acronym" only mean the cases where you pronounce it like "laser" (i.e one word), or does "acronym" in fact stand for the cases like "CIA" whose initials are pronounced? Now, in investigating that issue, my investigations lead me to believe that, in fact: The word "acronym" is, quite simply, not well-defined between the two cases. Thus, (1) surprisingly all "official" dictionaries, etc, poorly distinguish or simply do not distinguish, between the two cases, neither do they mention that (say) it specifically means 'both cases', nor only one case. (2) in academic and similar use of the term, once again, no real distinction is made between the two (3) when I asked a handful of intelligent, literate people what "acronym" means, and particularly asked them to distinguish between the two meanings, all of them in the straw poll just said the same thing, "You're right, that's weird, nobody knows what 'acronym' means." or words to that effect. (4) It's easy to find examples where people use 'acronym' to aggressively means only the "CIA" case, and it's easy to find examples where people use 'acronym' to aggreesivly means only the "laser" case,  My questions i) What is your opinion on which of the two cases acronym means ii) Can you in fact, unlike me, find some "definitive" reference on the issue iii) Can you perhaps see in some academic or article setting, clear distinction between the two possibilities? iv) Am I sadly correct that the word 'acronym', simply, fails in general use to distinguish between the two cases?


In Italy, you have two options to say "I love you", I'll try to translate them the best I can:   I love you (Ti amo.) I want you to be ok (Ti voglio bene.)    The fact is that in English, both ti amo and ti voglio bene are translated as I love you. But in Italian, there are lot of differences:   I love you is used to express love for another person which is, or you want her/him to be, your girlfriend/boyfriend.  I want you to be ok is used to express still something love-related but just a little bit less love-related (It's hard to say it). I want you to be OK is used by parents to their sons/daughters or vice versa or by a friend to another friend.   I do watch some TV shows in English and I find that sometimes two friends tell each other I love you and they just go back to their jobs (= I want you to be ok) and sometimes one of them says I love you and the other understands that he/she wants her/him to be his/her girlfriend/boyfriend and that it's love-related (= I love you). Why?


I'm not sure why guess isn't the same as words[random][0] even if I type the correct answer. It skips the if statment and goes to else.      do{  System.out.println("The scrambled word is: " + scramble[random]);                  Scanner fooBar = new Scanner(System.in);                  System.out.println("What is this word?: ");                 guess = fooBar.next();                  if(guess == words[random][0])                 {                     System.out.println("Congratulations, you have guessed correctly!");                     done = true;                 }             else                 System.out.println("Sorry, that is not it.");              }while(done == false);


Is it possible to automatically restart crashed services in Linux?

I am Using Ubuntu Server and would like to know if it's possible to automatically restart services that go unresponsive. I am operating a standard LAMP stack and occasionally vital services need to be restarted but I want to do it in a programmatic way.


Is there an adjective or phrase for "to be dealt with"?

I want an expression to refer a noun to be processed or to be dealt with. I think clauses a bit too long, while 'to-be-processed' phrase not elegant.  To specify my question in avoidance of ambiguous, I would state the context as explaining a model/method. I am about to write how the intermediate data between two procedures are like. So initially I consider sentence like "The to-be-computed/processed(by second procedure) data have features that blablabla."


Given is prime $p$ and a generator value $g$ with $1 < g < p$. How can we efficiently compute the order of the subgroup that is created by   $g^k \mod p$  I've looked into Eulers Totient function, but can not seem to find an efficient way to compute this with no additional knowledge apart from $p, g$. Am I missing something or can this not be calculated efficiently?


How can I set the box plot (i.e. axis) ratio of a usual 2D plot to a given value, say 4:3.  I don't want to use unit vector ratio since the quantities of the independent and dependent variables are of completely different orders of magnitude.


Drawing over a diagonal line, till a custom position

The following TikZ code  \documentclass[border=2mm,tikz]{standalone} \usepackage{tikz} \usetikzlibrary{positioning,calc} \usetikzlibrary{arrows.meta}  \begin{document}  \begin{tikzpicture}  \coordinate (a0) at (4,3);  \coordinate (a1) at (1.25,0.75); \coordinate (a2) at (3,-1);  \draw[dashed] (a1) -- node[pos=0.55] (a3) {} (a2 |- a0);  \draw[thick,-{Straight Barb}] (a1) -- node[pos=0.5, above=0.4em] {a} (a3);  \draw[-{Straight Barb}] (a1) -- (a1 |- a3); \draw[-{Straight Barb}] (a1) -- (a1 -| a3);  \draw[dashed] (a1 |- a3) -- (a3); \draw[dashed] (a1 -| a3) -- (a3);  \end{tikzpicture}  \end{document}   generates this output:    I would like to place an arrow vector along a diagonal line, ending at a custom point on the diagonal.  In the image, the vector should perfectly reach the intersection of the dashed lines. With  \draw[dashed] (a1) -- node[pos=0.55] (a3) {} (a2 |- a0);   I was expecting that a node labelled a3 was placed at position 0.55 of the above diagonal length, and so that the subsequent  \draw[-{Straight Barb}] (a1) -- (a1 |- a3); \draw[-{Straight Barb}] (a1) -- (a1 -| a3);   could meet exactly this point.  How to accomplish this?


Would several withdrawals (W) affect my chances at graduate school admission

I am an undergraduate math major and I have already had to drop two classes (one due to my mother being sick and other to do with an attendance policy). This semester I'm having trouble with my health and concentrating and debating on dropping two more classes. My GPA is a good 3.9 but if I stay with these classes I am risking a lower GPA (as I am only an upper freshman with 26 credits). I am getting A's in my two other classes. My questions are:  1. How bad are 4 W grades on a transcript when applying for a graduate program in mathematics?  2. Does having documentation saying I dropped due to depression/PTSD help if they can be "attached" to the transcript?  3. If I was able to do well in my GRE would that help soften the blow of a W grade?  Thanks. I appreciate any answers. I have only two days to drop with a letter grade W.  P.S. I am at City University of New York if that makes a difference and plan on going to grad school there too. I realize that my question is similar to  but it does not address GRE scores playing a role and whether documentation helps?


Why don't photons crash into each other occasionally? Or do they?

At the LHC, researchers smash particles into each other at speeds close to speed of light. Photons, on the other hand, already move at the speed of light. Do they ever smash into each other? Or do they just go through each other? Why?


Will a 9 speed crank work with 10 speed groupset?

Will this SLX 9 speed crank work with newer 10 speed groupsets? It looks to me that 9 and 10 speed cranks are the same. Or am I missing something? Are the spaces between the rings different?


Equivalent of shell 'cd' command to change the working directory?

cd is the shell command to change the working directory. How do I change the current working directory in Python?


What is the intuition behind chain rule in mathematics in particular why there is a multiplication in between?


But the proof here below is specially elegant.  Is there any function $f$ such that $f$ has a local minimum at $x$ but $\nabla f(x) \neq 0$?  Only assumption on $f$ is that it has to be differentiable at $x$ so that I can write $\nabla f(x)\neq 0$  to ask you this question.


For ordinals $\delta$ and $\beta$, if $\delta\in$ or $=\beta$, then there exists $\gamma\in$ or $=\beta$ such that $\beta=\delta+\gamma$

Prove that for ordinals $\delta$ and $\beta$, if $\delta \in$ or $= \beta$ then there exists an ordinal $\gamma \in$ or $= \beta$ such that $\beta = \delta + \gamma$.    I tried using transfinite induction on $\delta$  Base case seems simple, since you can let $\gamma = \beta$, but I'm stuck on the proof for both the successor ordinal and limit ordinal cases.  My class has not yet defined ordinal subtraction, so I can't use that in the proof.   Any help or hints would be appreciated!


Hi is it possible to get images from go daddy  to visual force pages.if it possible can you explain clearly how the process is.


Using HeapDumpOnOutOfMemoryError parameter for heap dump for JBoss

I was told I can add the -XX:+HeapDumpOnOutOfMemoryError parameter to my JVM start up options to my JBoss start up script to get a heap dump when we get an out of memory error in our application.  I was wondering where this data gets dumped?  Is it just to the console, or to some log file?  If it's just to the console, what if I'm not logged into the Unix server through the console?


Consider:  She's home. She's at home.  Are there any differences in meaning?


How to install Citrix receiver xubuntu 13.04 64-bit

Anyone have a walkthrough on installing Citrix receiver on Xubuntu 13.04 64-bit?    Update  $ sudo apt-get install libmotif4 nspluginwrapper   ... snip ...  Setting up libmotif4:amd64 (2.3.3-7ubuntu1) ...  Setting up nspluginviewer (1.4.4-0ubuntu5) ...  Setting up nspluginwrapper (1.4.4-0ubuntu5) ...  plugin dirs: nspluginwrapper: no appropriate viewer found for /usr/lib/flashplugin-installer/libflashplayer.so  Auto-update plugins from /usr/lib/mozilla/plugins  Looking for plugins in /usr/lib/mozilla/plugins  Segmentation fault (core dumped) Processing triggers for libc-bin ...  ldconfig deferred processing now taking place   sudo dpkg --install Downloads/icaclient_12.1.0_amd64.deb  Selecting previously unselected package icaclient.  (Reading database ... 155808 files and directories currently installed.)  Unpacking icaclient (from .../icaclient_12.1.0_amd64.deb) ...  dpkg: dependency problems prevent configuration of icaclient:  icaclient depends on libc6-i386 (>= 2.7-1);  however: Package libc6-i386 is not installed. icaclient depends on ia32-libs;  however: Package ia32-libs is not installed.  icaclient depends on lib32z1;  however: Package lib32z1 is not installed. icaclient depends on lib32asound2;  however: Package lib32asound2 is not installed. dpkg:  error processing icaclient (--install): dependency problems -  leaving unconfigured Errors were encountered while processing: icaclient


ACM now offers authors of published papers a choice of two copyright licenses: the "traditional"  or the .  How should I choose between these two licenses?  What are the advantages and disadvantages to the authors of each license?  I care a lot about maximizing the ability of others to read the paper (e.g., maximizing my ability to make my paper available on my web page, institutional repository, etc.); are there any relevant differences between the two licenses that affects this consideration?  Are there any other important differences between the licenses that authors might care about?


When designing decoupling capacitors why there are always parallel capacitors arrangements with decreasing values? It seems a redundancy to have this kind of configuration because the equivalent circuit is just one insignificant increase in the single larger capacitor.   Take this circuit as an example: isn't it the same to put only one capacitor 1,100uF? And why does it use a 0.01uF? I mean, the first capacitor tolerance is probably larger than that!  Please some insight!


How long was the longest given extra time in a half in football?

While watching a World Cup game, I noticed how the extra time given at the end of the first half is usually shorter than the extra time given at the end of the second half. That led me to wonder what was the longest extra time awarded at a football game, and after some reasearch I found this Bristol City game in 2000-2001 in a , where apparently 23 minutes of extra time were added:     "When Brentford played away at Bristol City in 2000-01, there were about 23 minutes of stoppage time in the first-half alone after a broken leg, a dislocated shoulder (Bees striker Lloyd Owusu passed out from the pain and an ambulance had to be driven up to the pitch), and serious concussion caused the delay," noted Will. "In fact, two goals were scored in that first-half injury-time, with the second being clocked in the 67th minute, I believe. The fourth official had originally held up 13 minutes' stoppage time, but one of the injuries occurred in that period to bump it up to 23. I'd be surprised if there were many games that contained more added-on time!"   Is this the longest extra time ever given during a professional football game? And if it isn't, what is the longest extra time period ever given during a professional football game?


Wifi keeps disconnecting in ubuntu 16.04

09:00.0 Network controller: Ralink corp. RT3290 Wireless 802.11n 1T/1R PCIe  Output of command ifconfig:    Output of command sudo lshw -C network:    How can I make my WiFi connections stable and stop them from disconnecting automatically?  Everyone who said it is a duplicate of some other questions , those solution didn't fix my problem :( . Please help


How do I pass data between hooks that don't interact?

How do I pass data between hooks that don't interact between them, or between a menu callback and a hook?  In the case the two hooks have a parameter in common, and that parameter is passed by reference, that is easy. What do I do when the hooks, or the menu callback and the hook, don't get a common parameter?