I'm struggling with the following piece of code:  def function(param):     if(param == 'notgen'):         return 'some text'     elif(param == 'gen'):         for x in range(10):             yield x gen = function('notgen') print(type(gen)) >>> <class 'generator'>   I suppose, this is expected behavior, but I cannot find proper docs. I need to yield and return values from one function depending on the situation.  Is it even doable?  Thanks everybody for suggestions!


Is it correct to make a sentence interrogative only with question mark (and tone) and without following essential grammatical rules?  For example, people usually say     You are going to the stadium?   instead of      Are you going to the stadium?   But, what about writing? I think doing so in writing may be problematic. Is there any specific rule for that?


I have been handed a PILZ flash drive from my friend, because it is apparently broken - indeed, it is. Connecting it to my computer instantly installed it's driver as a "XXXXXXXX U177CONTROLLER" device with 0MB of space, trying to view it results in a "Please insert media" message from Windows. I've read around, and found no fix for almost 2 hours now and I'm left totally clueless.


From page 115 in the Player's Handbook:     While the ward has 0 hit points, it can't absorb damage, but its magic remains. Whenever you cast an abjuration spell of 1st level or higher, the ward regains a number of hit points equal to twice the level of the spell.   The grouping of the two sentences in that paragraph makes it sound like the intent might be that the ward only regains hit points if it has 0 hit points when the spell is cast.  In a previous paragraph on the same page, it also states:     The ward has a hit point maximum equal to twice your wizard level + your Intelligence modifier.   The maximum would never be reached if the ward only regains hit points when currently at 0 hit points (wizard level will always be greater than spell level). That seems to confirm that we should only consider the second of the sentences above when determining when the ward gains hit points.  Is it correct that Arcane Ward always gains hit points when casting an Abjuration spell of first level or higher, up to the ward's hit point maximum, even if the ward already has some number of hit points?


enumerated list in proof - margin, qed symbol

I have two questions. 1. Can I delete the red-colored space? 2. If I use enumerate in proof, QED symbol appears the next line of the end, as above. If I do not want to type manually \qedhere, should I use ntheorem?  \documentclass[a4paper]{article} \usepackage[scale=0.75]{geometry}  \usepackage[english]{babel} \usepackage[utf8x]{inputenc} \usepackage{amsmath} \usepackage{amsthm} \usepackage{amssymb} \usepackage{textcomp} \usepackage{enumitem} \setlist[enumerate]{nosep, label=(\arabic*)}  \theoremstyle{definition} \newtheorem{lem}{Lemma}  \begin{document}  \begin{lem} \begin{enumerate} \item xxxx \item yyyy \end{enumerate} \end{lem} \begin{proof} \begin{enumerate} \item xxxxxxxxxxxxxxxxxxxxxxxxx. xxxxxxxxxxxxxxxxxxxxxxxxx. xxxxxxxxxxxxxxxxxxxxxxxxx. xxxxxxxxxxxxxxxxxxxxxxxxx. xxxxxxxxxxxxxxxxxxxxxxxxx. xxxxxxxxxxxxxxxxxxxxxxxxx.  \item yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. yyyyyyyyyyyy. \end{enumerate} \end{proof}  \end{document}


What paperwork do I need as support for a UK Standard Visitor visa application?

I am a Bangladeshi citizen, residing in Nigeria for 13 years. I am currently working in Nigeria for over wo years. I intend to go to UK alone in April, 2017 for one month in order to participate in PLAB 2 examination for doctors. My father, who is also a practicing doctor in Nigeria, will be my financial sponsor.  Will I need to submit my own bank statements alongside my father's bank statements while applying for the visa?  Also, do I need to submit police verification report and TB clearance report for UK Standard Visitor visa?


System don't recognize ubuntu partition ""All boot options are tried. Press F4 key to recover."

I just formatted my Samsung Ultrabook and installed Ubuntu 12.04 via USB using rufus to create the bootable USB (my ultrabook don't have a cd/dvd reader). The problem is, when the instalation finish and ask for a reboot, it skips the hdd boot and start via USB right away, and when I remove the USB it says "All boot options are tried. Press F4 key to recover..." Wich I suppose says that I don't have a valid OS installed in my HDD. I reinstalled in the same partition overwriting the former ubuntu installation (the live cd recognized the previous installation). Same problem. After that I followed the instructions from here:  And the same happened. I don't know what to do, and I can't use my ultra anymore. Help pls!  EDIT: I tried installing Windows 7 in half my hdd. Everything ok. But when I installed Ubuntu in the other half, I can't access to any of them. At startup says:  "error: file not found. grub rescue>" However, I can access both OS with the bootable Super Grub Disk in my pendrive. Using the Super Grub I managed to install Lilo in my Ubuntu partition. After installing Lilo, the computer booted normally only windows 7. With further google hunting I read that this can be a grub problem, and messed up with grub settings via terminal. After that I can't access any OS, neither I can get to boot with lilo (can't find config files). Now I know it's a problem with the boot files, not the ubuntu partition. What can I do? Is there any other boot type that may work for me?


I am integrating sales force with an external website.  The developer at the external end will push the data into sales force. and it will be in P.H.P script format.  Then how will I get that data into sales force. can I use it directly or do I need to de serialize or write a code to get that data into sales force.  The data he will send is related to accounts and contacts.  Any suggestions.


I downvoted an answer and commented to explain the downvote, then received 3 random downvotes on old answers I posted

I provided some feedback on an answer and downvoted it. Very soon after I received 3 downvotes for random answers I posted (which generally had upvotes) within the same minute and the answer I downvoted was removed.  Is behaviour like this captured and monitored? Whilst I cannot say for sure that a person did this maliciously, it seems likely in this case. I know it's only points so I don't mind but I am interested in what is done "behind the scenes" to stop this kind of behaviour.


I've got five sounds now for a game I'm working on currently. In the game, you can fight against other civilizations in big battles, but you can also settle on planets in peace.  Some of the songs are more violent, while others are quite peaceful. The question is: what is the best practice for changing between the songs. Is it better if I just look "is it peaceful or not" when the old song ends and then play a new one or should I do that every single frame and change the songs immediately.  The first alternative would sometimes play silent songs in battles (because the song started before the battle and isn't finished yet) and the second one would switch between to different-fast songs properly at the wrong moments so the player would hear a cut.  So I'd like to know what is more natural for the player or if there is a different possibility.  PS: The songs are between 300 and 500 seconds long.


Should the weight of downvotes be increased?

When we started Stack Overflow, we wanted to make sure that downvotes were more of a visual and psychological motivator than a punitive action. That's why    upvotes are +10 downvotes are -2, and cost the casting voter -1   However, recently, I've seen Marc Gravell and Jon Skeet both say similar things:     IMO, downvotes don't quite carry enough... -5 downvotes and +1 upvote (for sympathy) yields zero points overall; or it could even yield +10 points for a new user! I'd prefer to see, say, -4 points? -5 points?   I am starting to come around to this way of thinking. There are some users who ask a lot of questions that get downvoted heavily, but over time these users end up with a fairly sizable amount of reputation.  This doesn't feel right.  We are considering changing downvotes to -5, with the same -1 cost to the casting voter.  There really aren't that many downvotes in the system, so the net effect of this change would be to reduce rep growth for users who tend to get downvoted as much as they get upvoted. (Yes, I realize this is no panacea: over time, we'll still get rep inflation for marginal users based on sheer quantity; this is only one of several changes we are considering to help mitigate this.)  The other downside to this change, besides the obvious minor loss of rep for most users, is that it would force a global reputation recalc for every user. I think we're due for one of those anyway.


How to sort out permission problem on mounted partitions?

I have just installed a citation manager Zotero using snap. I added one of AddOns called Zotfile to locally manage PDFs instead of storing them on a cloud. I configured Ubuntu such that my Documents are on mounted partition. I also use LVM. Within Zotero, when I try to configure the AddOn Zotfile and point at one of the folders on a mounted partition, I get permission error. When I use any local folder on the same partition, everything's OK. How can I solve the problem? I am confused because Zotero is installed by root and has root:root permissions.


"Happy Birthday sir!" or "Happy Birthday, sir!"?

Which one is grammatically correct?   Happy Birthday sir! Happy Birthday, sir!   And where should I put "sir" in this sentence?   Congratulations for completing another trip around the sun!   Also suggest the position of the exclamation mark. Is it necessary or not?


Can I split one Ethernet line coming out of my wall into multiple separate lines?

I live in an apartment which provides Internet service included in the rent. They use a company called Pavlov for the Internet    wireless seems to be working fine but wired connection is at least %30 faster.  Ethernet, Cat5 outlet is built in the wall, and there is only 1 outlet in each room.  I would like to take this 1 outlet coming out the wall and multiply it into 4 wires, for desktop, Playstation, TV and laptop, without losing any Internet bandwidth.   I have absolutely no idea whether this line is coming from a switch or a router but I have been researching Ethernet splitter, routers, switches, hubs and haven't found a solid answer.   Is there a way I can do this?  This picture cleared up few things:     It seems that an Ethernet switch is to Ethernet as a USB hub is to USB, but with packet inspection.  What is a 10/100Mbps Network Switch, actually, and what is the cap?


Quotient of two integrals $\frac{\int_0^\pi x^3\ln(\sin x)\,dx}{\int_0^\pi x^2\ln(\sqrt{2}(\sin x))\,dx}$

Calculate   $$\frac{\int_0^\pi x^3\ln(\sin x)\,dx}{\int_0^\pi x^2\ln(\sqrt{2}(\sin x))\,dx}$$   In this problem, I'm unable to understand how to start.  I tried applying integration by parts but I couldn't solve it. I also tried the various properties of definite integration but they were of no use. Maybe applying integration by parts (or DI method) successively may work but it leads to a form of $\frac{\infty}{\infty}$.


Cannot install Ubuntu 14.04 on ASUS X453M

I was delighted when my daughter asked me to convert her laptop to Ubuntu after being very disappointed with Windows 10, so quick as a flash I built a new 14.04.3 LTS USB and tried to 'Try Ubuntu without installing'...  And it just freezes at the splash screen.  Checking a number of posts, I have updated the BIOS to the latest version and when I run the boot in verbose mode, it just hangs after the comment  *Starting system logging daemon  I've not had a problem either installing Ubuntu before (either full drive, dual boot and Ubuntu Studio) so any help would be greatly appricated so I can get my daughter back into real computing.


Windows Update on one of our Windows Server 2008 machine stopped working. Whenever I click on Install Updates, it fails with the 800B0100 error. I did some investigation and noticed that it’s not an uncommon error. I found a number of discussions threads reporting the same error on Windows Vista. However, I could not find any leading to a useful conclusion. I also found a Microsoft KB article (), but it’s not very revealing. It recommends to run . When I ran it, it looked like a long update, and when it finished, it did not say anything. So I assumed it did whatever it wanted to do. I found some logs which the tool supposedly produced, but there were full of gibberish to me. Also, the tool did not guarantee to fix all problems.


How to show that $a_n=\left(1+\frac{1}{n}\right)^n$ monotonic growing

I have to show that $a_n=\left(1+\frac{1}{n}\right)^n$ is monotonic increasing. I struggle alot and tryng to find a right form to epxress that, $a_n\le a_{n+1}$ a little hint what might help would be great. Im in my first year in the introduction to real analysis, so tipps with derivative or more advanced arent usefull :/ I really only like to get a little hint :)


why does fdisk add one additional sector when creating partitions?

I'm playing around with fdisk and I tried to create a partition on an empty USB drive. Here's how that went: Command (m for help): n Partition number (1-128, default 1): 1 First sector (34-61187102, default 2048): 2048 Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-61187102, default 61187102): +30000000           Created a new partition 1 of type 'Linux filesystem' and of size 14,3 GiB.  so just one partition with 30 million sectors. However, when I check how many sectors it contains I get:  I'm checking with a different program and I see again that additional sector:  Sorry for the pettiness :) I'm learning.


Set output audio of windows as input audio of microphone

is it possible to set a virtual microphone which captures the windows audio? The goal is to record audio with google docs. Thank you.


Why was one Informed badge awarded here on Meta?

I've gathered from   that the Informed badge is not awarded here on the Big Meta.  But  does have this badge.  Why did this one user get the badge when the rest of us can't?


Show that there are finitely many different principal ideals

Let $R$ be a U.F.D. and $0\neq d\in R$.   I want to show that there are finitely many different principal ideals that contain the ideal $(d)$.   $$$$   We have that $R$ is a U.F.D. iff $\forall r\in R\setminus \{0\}$, $r\notin U(R)$ the following hold:    $r=a_1 \cdots a_k$ with $a_i$ irreducible  If $r=a_1 \cdots a_k=b_1 \cdots b_t$ with $a_i, b_i$ irreducible then $k=t$ and $a_i=b_iu_i$ with $u_i\in U(R), \forall u=1, \dots , k$.    $$$$   A principal ideal is generated by a single element, say $i$,  and so that it contains the ideal $(d)$, $i$ must divide $d$, right?   To show that $d$ has finitely many divisors do we use the definition of a U.F.D. ?   $$$$   EDIT:   We have that $d=a_1^{k_1}\cdots a_r^{k_r}$ with $a_i$ irreducible.   Since $R$ is a U.F.D. the irreducible elements are prime.   Does it follow from that that the divisors of $d$ are of the form $a_1^{j_1}\cdots a_r^{j_r}$ with $0\leq j_i\leq k_i$ ?   From that we get that the set of the divisors is finite, right?


I was reading some gstreamer code and fell on this line  register int i;   Does anyone know what the register keyword does ?


Does "Sacrifice a creature" trigger "sacrifice this creature"

When choosing a creature to sacrifice (originated from a "sacrifice a creature" instruction), if the creature that is being sacrificed has "sacrifice this creature (for whatever result)", does it trigger?  Does it make any difference if the target creature is a forced sacrifice instead of a volunteered sacrifice?  Example scenario: I play  to draw 2 cards and target  as the sacrifice. Does this trigger Bile Urchin's "Sacrifice Bile Urchin: Target player loses 1 life."?  I may have thought about this for too long and confused myself, so a little clarification would be great.


Vertically center contents of table cell

Consider the following example:  \documentclass{article}  \usepackage{pstricks-add} \usepackage{booktabs}   \psset{   unit = 0.7,   dimen = middle,   ticks = none,   labels = none }  \newcommand*\pind[2]{%  \psset{linecolor = red}   \psline(#1,0)(#1,#2)   \psline(!#1 0.2 sub #2)(!#1 0.2 add #2) } \newcommand*\enkeltobservationer{%   \begin{pspicture}(-0.5,-0.2)(5.9,6.3)     \psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]     \pind{0.5}{3}     \pind{1.0}{5}     \pind{1.5}{3}     \pind{2.0}{3}     \pind{2.5}{4}     \pind{3.0}{2}     \pind{3.5}{5}     \pind{4.0}{1}     \pind{4.5}{4}     \pind{5.0}{2}   \end{pspicture}% } \newcommand*\soejle[2]{%  \psset{fillcolor = red}   \psframe[fillstyle = solid](!#1 0.5 sub 0)(#1,#2) } \newcommand*\intervaller{%   \begin{pspicture}(-0.5,-0.2)(5.9,6.3)     \psaxes{->}(0,0)(-0.2,-0.2)(5.4,5.5)[\small{$x$},0][\small{$h(x)$},90]     \soejle{0.5}{3}     \soejle{1.0}{5}     \soejle{1.5}{3}     \soejle{2.0}{3}     \soejle{2.5}{4}     \soejle{3.0}{2}     \soejle{3.5}{5}     \soejle{4.0}{1}     \soejle{4.5}{4}     \soejle{5.0}{2}   \end{pspicture}% }   \begin{document}  \begin{table}  \centering   \begin{tabular}{l c c c}     \toprule      Begreb               &      Forkortelse          &      Enkeltobservationer  &      Intervaller            \\      \midrule      Hyppighed            &      $h(x)$               &      \enkeltobservationer &      \intervaller           \\     \bottomrule    \end{tabular} \end{table}  \end{document}     I would like to vertically center Hyppighed and $h(x)$ relative to the figures; how do I do that?


Why "vacuum" in vacuum Rabi splitting (VRS)?

What is the role of "vacuum" in vacuum Rabi splitting (VRS)?  Also, does VRS arise because of quantized nature of light?  If not, what is a semiclassical explanation for VRS?


How do I scroll a LinkedHashMap to a specific key? Something like this:  LinkedHashMap<String,String> queque = new LinkedHashMap<String,String>(); queque.put("uno","uno"); queque.put("due","due"); queque.put("tre","tre"); queque.put("quattro","quattro"); queque.put("cinque","cinque"); Iterator i = queque.entrySet().iterator(); while(i.next().getKey().equals(quattro)) {     System.out.print(i.getKey() + ": ");     System.out.println(i.getValue());     i.next(); }


How do I get add-apt-repository to work through a proxy?

I'm trying to follow the  (on my Ubuntu 10.04 VM).  The first step is:  sudo add-apt-repository ppa:linaro-maintainers/toolchain   But when I run that I get:  Error reading https://launchpad.net/api/1.0/~linaro-maintainers/+archive/toolchain: <urlopen error [Errno 110] Connection timed out>   I'm guessing the problem is with my configuration for my employer's proxy server, particularly for HTTPS.  When I opened  in Firefox, I got "The connection has timed out".  I then went into Firefox Preferences -> Advanced -> Network -> Settings... and set HTTP Proxy to "gateway" and Port to 8080, and checked "Use this proxy server for all protocols".  Then the page loaded.  This supports my theory.  I've tried setting the http_proxy and https_proxy environment variables (both lower and upper case):  $ set | grep -i proxy HTTPS_PROXY=https://gateway:8080 HTTP_PROXY=http://gateway:8080 http_proxy=http://gateway:8080 https_proxy=https://gateway:8080   I also tried changing them to:  $ set | grep -i proxy HTTPS_PROXY=gateway:8080 HTTP_PROXY=gateway:8080 http_proxy=gateway:8080 https_proxy=gateway:8080   And I tried adding this second line to /etc/apt/apt.conf:  Acquire::http::proxy "http://gateway:8080/"; Acquire::https::proxy "https://gateway:8080/";   But I continue to get the same error.  How do I troubleshoot this?  Update: I followed the instructions in the  to  and got further:  $ sudo add-apt-repository ppa:linaro-maintainers/toolchain Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver keyserver.ubuntu.com --recv 1DD749B890A6F66D050D985CF1FCBACA7BE1F97B gpg: requesting key 7BE1F97B from hkp server keyserver.ubuntu.com gpgkeys: HTTP fetch error 7: couldn't connect to host gpg: no valid OpenPGP data found. gpg: Total number processed: 0   I wonder if the "HTTP fetch error" means I also need to add "Defaults env_keep = http_proxy" to /etc/sudoers...  Update #2: I added:  Defaults env_keep="http_proxy" Defaults env_keep="https_proxy"   ...as in , but I still get the same "gpgkeys: HTTP fetch error 7: couldn't connect to host" error.  And this is curious:  $ sudo env | grep proxy https_proxy=https://gateway:8080   ...because http_proxy isn't there.  Any advice is appreciated.  Update #3: Since the host of my VM is a laptop, I took it home and tried there (with no proxies):  $ sudo add-apt-repository ppa:linaro-maintainers/toolchain Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyserver keyserver.ubuntu.com --recv 1DD749B890A6F66D050D985CF1FCBACA7BE1F97B gpg: requesting key 7BE1F97B from hkp server keyserver.ubuntu.com gpg: key 7BE1F97B: public key "Launchpad Linaro Overlay PPA" imported gpg: Total number processed: 1 gpg:               imported: 1  (RSA: 1)   It worked.  So problem is related to proxy configuration.  But I suppose I have a workaround.


There is situation like this:  <select id="trollSelect">     <option value="PL">Polish Troll</option>     <option value="EN">English Troll</option>     <option value="JP">Japanese Troll</option>     [...] //more options created dynamically </select>   Option values and Option texts are unsorted in Select. Is this possible to sort this options in JQuery or Javascript by value or text alphabetically ??  The result should be like that:  <select id="trollSelect">     <option value="EN">English Troll</option>     <option value="JP">Japanese Troll</option>     <option value="PL">Polish Troll</option>     [...] //more options created dynamically </select>


What command(s) can I use in a terminal to find a program that does a particular thing?

I often find myself alt-tabbing to google "How to do X in Linux".   Is there a way to search (say, man pages) in Linux to find tools that might be of use in a particular situation?   For example, earlier I needed the command to see how much space a folder was taking up. (Excuse my Windows terminology – I'm new to this!) Is there any way I could have found the du -h command without leaving the terminal?


On-hold questions and answers already submitted

Haven't found answer to this question, but I'm probably not looking in the right place.  Scenario:   Question is asked 2 Answers are posted Question is marked: "on-hold"   Can the OP accept one of the already-submitted answers?


Using Modelbuilder or Python to write output a folder name using database or table file?

Has anyone worked on Modelbuilder or python to write to automate creating a folder using the database or table file to write output a folder name and or/create the subfolders? I recalled I had an aml that allowed me to modify codes to allow to output new folders within the folder.  For example, you have a database that has the list of the name of the counties on the dbf file or table and then insert it to the Modelbuilder. Example name of county : Dona Ana and then use that name to create a folder Dona Ana  ( to hold imagery for NAIP on the server when I get all of the New Mexico counties in a hard drive to me)    I'm adding this screenshot to show what I am doing wrong... ( This is the pre-screenshot) that was done yesterday December 9th.   Now that that i have figured it out and here is the screenshot December 10th.


To understand how to start multiple threads calling the same method, I want to use the following logic:   Create an array of threads Initialize the Threads using a lambda expression Start the threads.   The routine works if I use the Join function or if I start threads directly like this:   new Thread(EnterSemaphore).Start(i);   What I can see from the result is that the routine I am using is not working. Not all threads are displayed and I even see a thread with index number 6. I would like to understand why starting an array of threads like this fails.  class SemaphoreLock {      #region Fields     // SemaphoreSlim _sem heeft de capaciteit voor 3 elementen      static SemaphoreSlim _sem = new SemaphoreSlim(3); // Capacity of 3      public readonly object StartLocker = new object();      #endregion      #region Constructor     //      public SemaphoreLock()     {         Thread[] testStart = new Thread[10];          for (int i = 1; i <= 5; i++)         {              // If enabled, this works             // new Thread(EnterSemaphore).Start(i);              // This is not working.             testStart[i] = new Thread(() => EnterSemaphore(i));             lock (StartLocker) testStart[i].Start();              // Adding a join here works, every thread is started as a single thread             //testStart[i].Join();         }      }     #endregion       #region Methods     static void EnterSemaphore(object id)     {         Console.WriteLine(id + " wants to enter");          // Block the current thread until it can enter the Semaphore         _sem.Wait();          Console.WriteLine(id + " is in!");         Thread.Sleep(1000 * (int)id);         Console.WriteLine(id + " is leaving");         _sem.Release();          if (_sem.CurrentCount == 3)         {              Console.WriteLine("Done...");         }     }         #endregion  }


Suppose $R$ is commutative, and let $M$ be a free $R$-module of finite rank. Prove that if $A$ and $B$ are bases of $M$, then $|A| = |B|$.  I can't really figure out how to prove this theorem.


I'm new to Latex so forgive me if the questions are dumb...  I was trying to right left-top corner superscript, someone recommended mathtools package on this forum: .  So I downloaded , unzip it, there's an "mathtools.dtx". In the package there are documents but none talked about how to install, I fancy the installation is just too primary to real Latex users.  OK, then, there's still another thread here explained the steps:  . So here I follow   I ran "tex XXX.dtx" (there's no *.ins files) on all the .dtx files under the extracted folder, that includes: breqn.dtx, flexisym.dtx, mathstyle.dtx, empheq.dtx, mathtools. Then I created a folder "C:\athos\localtexmf\mathtools" and put all the new files in.  Then I go to "Windows -> Start -> Programs -> MikTex 2.9 -> Maintenance (Admin) -> Settings (Admin) "; in "Roots" tab I added path "C:\athos\localtexmf"; in "General" tab I clicked "Refresh FNDB" and then clicked "OK" to close it. I restarted my WinEdt, added  "\usepackage{mathtools}" under "\documentclass..."; and added "test  $\prescript{14}{2}{\mathbf{C}}$ " in the main body.   After that when I try to "MikTex", the error still comes up: "The required file tex\latex\mh\mathtools\sty is missing. It is a part of the following pakage: mh . The package will be installed from ..."  Seems the folder "C:\athos\localtexmf\mathtools" is not captured by MikTex?  Then in the error message dialog, I choose "Change", choose "Package shall be installed from a directory", click "Next", choose ""C:\athos\localtexmf\" or "C:\athos\localtexmf\mathtools", in either try it says "Not a local package repository".  What shall I do?  I'm on Microsoft Windows XP Prefessional SP3, WinEdt 8 (Build: 20140613  (v. 8.2) - 32-bit), and MikTex 2.9.


An invalid argument, the conclusion of which is a tautology

Why it is not possible to have such argument?  I found some textbook Introduction to Formal Logic and this is from one of the first excercises. This is marked as impossible, but I do not understand why.


How does $\vec{\beta}=(H^TH)^{-1}H^T\vec{y}$ equivalent to least squares criteria for evaluating splines?

I'm learning about splines and the equation for a spline trying to predict the true function given data points is expressed as $$f(x)=\sum^k_{m=1}\beta_mh_m(x)$$ Where $\beta_m$ is some linear coefficient, $h_m(x)$ is a basis function and $k$ is the number of regions/areas separated by knots. I read that the least squares criterion is used to estimate the coefficients($\beta$), which makes perfect sense for evaluation. Then it goes on to say you can solve for all $\beta_m$ using matrices. $$H = \begin{bmatrix}h_1(x_0) & ... & h_k(x_0)\\ ... & ... & ... \\ h_1(x_n) & ... & h_k(x_n)\end{bmatrix}$$ $h_i, i\in[1,k] :$ basis functions $x_l, l\in[0,n] :$ Independent data points being approximated $$\vec{\beta}=(H^TH)^{-1}H^T\vec{y}$$ $\vec{y}$ : Vector of response variables to each $x_l, l\in[0,n]$ so $\vec{y}=[y_0,...,y_n]$ $\vec{\beta} = [\beta_1 , ..., \beta_k]$ How does $\vec{\beta}=(H^TH)^{-1}H^T\vec{y}$ result in minimizing least square criteria?


Problem with formatting expectation using a command

Here's the minimal example \documentclass{article} \usepackage[utf8]{inputenc}  \usepackage{amssymb} \newcommand{\bbE}[1][X]{\mathbb{E}\left[#1\right]}  \begin{document}  Working: $\bbE[XY]$  Broken: $\bbE[\bbE[X]] \bbE[\bbE[Y]]$  \end{document}  When I run this I get the following error:  Missing delimiter (. inserted).


Layers section is not in the render settings panel?

I'm very new to Blender and I have been watching some tutorials on how to make models within it. In every one of these, their render settings (In the properties tab) have a Layers section below the Performance section.   My version of blender does not seem to have that, at least by default. I've looked around the user preferences and haven't found anything. Thanks for helping.


How to Enable QuickPath (Swipe) keyboard on iPad

iOS 13 delivered a a new “swipe to type” keyboard called QuickPath.  .  This is similar to the  on Windows Phones and the  for Android.    It’s enabled by default on the iPhone, but not on the iPad. How can I enable this useful feature?


Suppose $f$ and $g$ are entire functions with $|f(z)|\leq|g(z)|$ for all $z$.  How can we show that $f=cg$ for some complex constant $c$?  Thanks for any help :)


I need to enable scroll lock so I can toggle lights on my keyboard. This works on Arch.Funny thing it doesn't work on Ubuntu.    $ xmodmap -e ‘add mod3 = Scroll_Lock’ xmodmap:  unknown command on line commandline:1 xmodmap:  unable to open file 'mod3' for reading xmodmap:  unable to open file '=' for reading xmodmap:  unable to open file 'Scroll_Lock’' for reading xmodmap:  4 errors encountered, aborting.


$x^p -x-1$ irreducible over $\mathbb{F}_{p}$

Show that $x^p - x -1$ is irreducible over $\mathbb{F}_{p}$.  I've seen this polynomial (or some variation x^p -x -a) on several of our qualifying exams and in every case they ask you to show it is irreducible. I know you can show it is irreducible by showing that if $\alpha$ is a root of it then $\alpha+1$ is also a root and then showing that it is the minimal polynomial for its roots. This takes about half a page of writing to do and I am looking for a shorter way to prove this.     Anyone have a shorter way?


In a box there are 4 balls. Red, Yellow, Blue and Green. We draw a ball from the box. If the ball is red then we replace it by a yellow ball, if the ball is yellow then we replace it by a blue ball, if the ball is blue then we replace it by a green ball, if the ball is green then we replace it by a red ball. Find the expected no of drawings such that all balls will be of same colour.


Iterating through a list of mongoose documents returns 0

I have a mongoose schema which consists of an author object, content, comments, cotes, creationDate, creationIP, and creationLocation. The problem is, that if I iterate through the list returned by Application.find(), it doesn't seem to find any documents.  My code  This is inside an async () => {} function.  const applications = await Application.find(     { _id: user.notReviewed },     { _id: true, content: true, creationDate: true, author: true, votes: true });  console.log(applications)  for (application in applications) {     console.log(application) }   returns  [ { author: { username: 'Dextication', _id: '1234567890' },     votes: [],     creationDate: 2019-04-26T15:24:37.000Z,     _id: 5cc321e529b4745b3474a641,     content: 'Yeah, well that was fun!' } ] 0 // this should be the above argument in the array


Google Force Adding 'Site name : ' on Search Result

Can Anyone Help Me to Remove Sitename: from google Search results.   This is my real title name <title>Web Design & Web Development | Ixeun Software Solutions | Batticaloa</title> but google adds iXeun: Web Design & Web Development | Ixeun Software Solutions | Batticaloa from search results this is little bit confusing for me.   Please Search for site:ixeun.com on google so you will find my home page link root shows like above.


Get real position of an HTML element in pure javascript

How to get the real coordinates (top and left) in the screen in pure JavaScript?  Methods I found use recursion on parent elements to calculate the coordinates, but it seems that they do not cover all the webpage, like ,  and


Proof of $\lim_{x\to\infty} \frac{a^x}{x!}=0$ when $a$ is a constant

I was working through the proof of the convergence of the Maclaurin series for certain functions, and I came across this limit, which I want to prove, but am not sure how to prove. $\lim_{x\to\infty} \frac{a^x}{x!}=0$, $a>0, a\in N$ For this limit, techinically $x!$ should grow faster than $a^x$ for any value of $a$, but when $a$ is really big, then the limit becomes hard to prove. Using L'Hospital is not really feasible, as an exponential function always has an exponential in its derivative and the factorial function doesn't have a derivative. I then tried using the definition of limits: Limit is true when for all $\varepsilon>0$ there exists $m$ such that if $x>m$, then $∣f(x) ∣ = |\frac{a^x}{x!}|<\varepsilon$. But then I have no clue what value $m$ should be relative to $\varepsilon$. I'm not sure if this is the way to solve the limit.


So I am trying to make a model with hand painted textures. I marked some seams and UV unwrapped it to start painting. (maybe i forgot a step?), but then i try to apply it. I don't really know how to apply it. And once I thought i succeeded, but when I opened up the file again it was blanc.   Anyone knows how to do this?


I have the following nginx config, e.g.  server {         listen   80;         server_name example.com         allow 127.0.0.0/8;   When I restart, it warn me:  Restarting nginx: nginx: [warn] server name "127.0.0.0/8" has suspicious  symbols in /etc/nginx/sites-enabled/xxx   Any idea?


I need to rename a user account on Windows 7 Home Premium.  If I go into the User Accounts control panel applet and choose Change your account name, Windows changes the account's Display Name.  I want to change the actual user name.  How can I do this?  I've looked at the net user command but it doesn't seem to be able to do this.  On Windows Pro I could use lusrmgr.msc but that's not available on Windows Home edition.


I would like to forecast for next 2 months using 1 year data captured at monthly level.  sample of the data    201702  7 201703  1344 201704  1311 201705  2645 201706  8581 201707  7271 201708  11550 201709  11372 201710  7089 201711 10677 201712 9147 201801 2992   first column indicated month, second column indicates demand of product. I have used time series like arima, ets, ma all of them over fit.  Can you suggest some basic models that may solve the problem?  Thanks


Unable to login after renaming user folder in Windows 10

I renamed my folder under Users in Computer Management from "denni" to "Dennis". I then opened an Administrator Command Prompt and used   net user Administrator /active:yes   and the command completed successfully. I opened Windows Explorer and I renamed the User folder from "denni" to "Dennis". When I tried to sign out and and sign back in, I get the message that Windows was unable to sign me in and to try to sign out and sign in again.   Every time I try I get the same message. I don't know what to do now! Please help!


Issue with installing Teamviewer - The following packages have unmet dependencies

I have an issue with installing Teamviewer on fresh install of Ubuntu 20.04 LTS.  Does anyone knows what I've done wrong?


What power was Luke using at the end of The Last Jedi?

When Luke used the Force in his      final move to distract the First Order on Crait,   what power specifically was he utilizing? Force projection? Force illusion? Mind-trick?  The simple answer is to assume Luke was projecting himself onto the planet but is it possible he was manipulating everyone's mind into seeing an illusion instead? I've never read where Force users could project themselves at such a great distance but it's not unheard of for a Jedi or Sith to effect the minds of other beings from across the galaxy.


Role of dependencies while installing software??

What is the role of dependencies while installing any software?I was installing vlc player and it were closed by giving me error something like check dependency .  What is to solution of this and how i'll get these dependencies??  Thanks in Advance.


Denoise a bunch of images with correct output names

I have a Blender project set to denoise images rendered in Source Filmmaker. It actually does de-noise the images correctly, but the problem is that the setup and output is confusing. Regarding the setup in the compositor, let's say I have SFM render images 0-1999 (SFM output starts at frame 0), does that mean that the start frame when using the image sequence in the compositor is 1 and the end is 2000? Regarding the output, I noticed Blender starts at frame 1, but I want it to map the first frame to frame 0 since Source Filmmaker starts at frame 0 to avoid confusion with the output file names between both programs. How can I do this?


Super key not showing "Activities" if the keyboard layout is not English

I use different keyboard layouts on my computer. The Super key works as expected with "English (with dead keys on Alt-Gr)" showing the Activities overview, but when switching to other layouts, the Super key has no effect. Combinations like Super+L or Super+A work as expected on every layout.  I've used xev to check that the keystroke is detected, and the output of xev is the same for different keyboard layouts.  I've updated the official Ubuntu (GNOME) 18.04 to 20.04. The issue was not happening before the upgrade and I'd like to avoid "fresh reinstall" as a solution.


During the process of crossing over, Why is the maximum possible recombination frequency between two genes equal to 50% and not more than that?


I came up with this question when I received an email from a committee with a sentence 'We have decided not to publish it', which seems really strange to me because the grammar I learned in English classes is 'decide not to do something' and 'decide to not do' was told incorrect.  I searched for answers to this problem online, but did not find a clear as well as persuasive answer. In terms of grammar, is 'decide not to do' correct ? If it is incorrect, is there a reason why people say 'decide not to do' even in official letters ?


I have four tables on one line that I would like to refer to as separate figures. I would like them to appear like this:    This is how the tables currently appear:    \begin{table}[h!]   \medskip      \begin{tabular}{|c|c|c|}         \hline         -1 & -1  & -1 \\ \hline         2 & 2 & 2 \\  \hline        -1 & -1  & -1 \\         \hline     \end{tabular} \hfill      \begin{tabular}{|c|c|c|}         \hline         2 & -1  & -1 \\ \hline         -1 & 2 & -1 \\  \hline         -1 & -1  & 2 \\         \hline     \end{tabular} \hfill     \begin{tabular}{|c|c|c|}         \hline         -1 & 2  & -1 \\ \hline         -1 & 2 & -1 \\  \hline         -1 & 2  & -1 \\         \hline     \end{tabular} \hfill     \begin{tabular}{|c|c|c|}         \hline         -1 & -1  & 2 \\ \hline         -1 & 2 & 1 \\  \hline         2 & -1  & -1 \\         \hline     \end{tabular} \captionof{figure}{Masks for line detection} \label{table:mul} \end{table}   I want to caption each of the tables with (a) text, (b) text, ect.  What is the proper way to do this, so that I can caption each of the tables, but referenced as figures?


I seem to recall it being stated that the 1.2 update includes a number of new, friendly NPCs. What are they, and what are the requirements for each to appear?


a conjecture on the binary operation of multiplication

Give a conjecture describing the values of $n$ for which all of the nonzero elements of $Z_n = {0, 1, 2, . . . , n − 1}$ have multiplicative inverses.  I am guessing the point of not having $0$ included is so nonprime numbers of $n$ will now have inverses, but I want to make sure this is the case.


Let $a$, $b$ and $c$ be the three sides of a triangle. Show that $\frac{a}{b+c-a}+\frac{b}{c+a-b} + \frac{c}{a+b-c}\geqslant3$.

Let $a$, $b$ and $c$ be the three sides of a triangle. Show that $$\frac{a}{b+c-a}+\frac{b}{c+a-b} + \frac{c}{a+b-c}\geqslant3\,.$$  A full expanding results in: $$\sum_{cyc}a(a+b-c)(a+c-b)\geq3\prod_{cyc}(a+b-c),$$ or $$\sum_{cyc}(a^3-ab^2-ac^2+2abc)\geq\sum_{cyc}(-3a^3+3a^2b+3a^2c-2abc),$$ but it becomes very ugly.


Is it possible to create one function instead two functions of same purpose but different argument type? (Can I remove duplicate code?)

Is it possible to create one function instead two functions of same purpose but different argument type?  I have two functions written in C, they convert image from RGB to HSV:  void png_rgb2hsv(pPNG_DATA data); void jpg_rgb2hsv(pJPEG_DATA data);   they do exactly same thing: they take data->row_pointers and cycle it in a loop data->height times. Then it convert the values referred by data->row_pointers. This is how it works. But the only difference is that the data structures use different types. It seems to me senseless to use two functions for same thing. Especially when I would add more functions for more color spaces.  How this problem of program design is solved in practice in C?  Update: Most of readers didn't understand the question. I did not asked about overloading. It was question about design. I ask if is it possible to remove redundant function, "redundant" code. Because both functions are using same code, do the same thing, but the types in the function argument are different because one type is from libjpeg and the second type is from libpng. What I found is that it is not possible because it would mean use one variable for two different types.


Evaluation of $\int_{1}^{\infty} \frac{\arctan (x+1)}{x^2+4} dx$ in closed form?

I have used the substitution $u= x+1  $ then $du =dx$ to evaluate the following integral in closed form and since $\arctan$ is connected to $x^2+1$ as it is a derivative of it. $$\int_{1}^{\infty} \frac{\arctan (x+1)}{x^2+4} dx$$  But i didn't come up to it's closed form the  me the closed form for it , and all my attempts gives me this approach : $$\int_{1}^{\infty} \frac{\arctan (x+1)}{x^2+4} dx=\frac{\pi^2}{8}-\frac{3\pi}{8}\arctan \left(\frac{1}{2}\right)$$ But this is not the same result with , Any way ?


I have been working with LaTeX, under TeXMaker (latest version 3.2.2) for several months, and recently added PGF/TikZ capability. On that occasion I feared there would be problems as I really have very little understanding of how the various applications hang together, or even where to find them. But no, once I found where TeXMaker resided I simply added the PGF files as a subdirectory and to my complete surprise, it all worked. Similar success was had with adding tikz-3dplot capability.  Recently, working my way through the TikZ manual I wanted to experiment with gnuplot, and all hell broke loose. I am even unable to find what type or version of LaTeX I am working with, i.e. cannot find executables. I know I have MiKTeX 2.9 loaded as I recall pulling it off the net, but if this is the variant of LaTeX my TeXMaker is working with I cannot tell. The one thing I do find is texmaker.exe, everything else is turning into a complete mystery. Without a doubt I am coming across as a complete air head, but my main interest lies in mathematics, but realize I need to invest effort to make the most of LaTeX and its graphic capabilities as a tool.  Could someone kindly point me to a brief and succinct overview of how the following hang together: LaTeX, TeXMaker, PGF-TikZ, gnuplot. I am working under Windows 7.


How is it that lowering the number of frequence,$n$ by $1$ in the for formula for Population and Sample Variance account for the discrepency of using sample rather than population.  I mean how is dividing the whole expression by $n-1$ in sample variance better than dividing by $n$?  I am referring to the formula $$s^2=\frac{\sum_{i=1}^{n}({x_i-x_{avg}})^2}{n-1}$$ more accurate than $$s^2=\frac{\sum_{i=1}^{n}({x_i-x_{avg}})^2}{n}$$  Thank You.


How many different ways are there to color the faces of a cube with six different colors?

Think about: If the cube is held in a particular orientation, there are 6! ways to paint the six faces. However, if you rotate the cube around, some of these colorings are equivalent. How many colorings are in each equivalence class?  So from what I understand, two colorings are equivalent provided that if the cube is rotated, they have the same coloring.  How can I tackle this problem? I know the strategy for anagrams, but maybe the context of this one is goofing me up. How can I find how many colorings are in each equivalence class?


Can we use the present perfect in this case?

In Korea, we learned that we should use the past tense when the subject is an historical event, as in "The Korean war broke out in 1950."  However, I think that when the event continues to affect the present (now), we should use the present perfect.  So I think that we can say 'The Korean war has broken out in 1950.'  Am I right?


Blender Materials not working / Viewport not rendering correctly

I got a new GPU (AMD Sapphire RX 550) and since then, Blender (2.91.0) doesn't display my Objects correctly in the Viewport, while I´m in Material Preview / Rendered mode. It seems like the Materials are not there / can´t be rendered. While I´m in the Shading tab my Object looks like the Background (maybe its invisible?) and as soon as I start rotating around it does not clear the Background from the Object (like those Object smearing effect in (buggy) games when the skybox is not cleard) I tried switching the Renderer but that didn´t work.


I can't get my GPU to work on any scene.  I have enabled both my CPU and GPU for Cycles rendering. But during render CPU usage gets to 100% and GPU does not go up (below 5%).  Here are my settings:     I tried unchecking the CPU in preferences, and in that case 10% of my CPU is working on the rendering.  The scene I am working on is not the problem because, I tried other scene, like the BMW benchmark for GPU. And still the GPU is not working.  I have all Nvidia drivers up to date (Game ready and Studio). I tried Blender 2.82a, and 2.83 no difference  I am looking for a solution, thank you for reading this.


What is the difference between "each day" and "every day"?   For example:      We talk every day.      We talk each day.


I'm having a problem that I've had before and I'm tired of hacking my way through it and hope that there is some supported solution.  I'll go ahead and create a document for example:  \documentclass {article} \begin{document} \section {Introduction} In the introduction of the document, you will find plenty of verbatim \verb|texts that| have an hard time wrapping. \end{document}   So, the problem here is that the \verb environment doesn't wrap well (unlike the example I posted above where I put in the return to aid in viewing).  There is an overfull hbox error.  How can I make the \verb command wrap and justify with its surroundings better?  I would expect LaTeX to just increase or decrease the spacing around the \verb command.  Is it just too much smooshing or stretching for LaTeX to agree to do it?  Thanks in advance for any help.  [EDIT] After reading  I think that \texttt may be the right way to go here.  This considerably covers the question above, but the question still stands: What about \verb?  [EDIT] Also see the related question about \texttt{}


Change the shortcut of cmd+Q for all applications

I use cmd+tab, cmd+W, cmd+A a lot and I don't remember how many times I hit cmd+Q accidentally.  Is it possible to change the shortcut for quitting applications from cmd+Q to something else (not to disallow using keyboard to quit applications), ideally for applications all at once (not to do it for individual application one by one)?


Advantages of Elliptic Curve cryptography

In digital signature schemes, what the security advantage of using Elliptic Curve over Integer Factorization and Discrete Logarithm schemes?


Granting access permission to normal user to a logical volume of a volume group

When I need to run a program with direct disk access, like read/write from /dev/sdb, I simply add the user to 'disk' group. In this way we don't need to disclose the root account the the user. However the user would also be able to access any other disks on the same machine.  Is there any finer-grained access control over this need? Could we assign full-access of disks, volumes, or volume groups to some users or groups? When a user need a physical disk to do his own stuff, I won't have the concern that he may destroy the other parts of the system.  (I tried to set owner of a /dev/sdb to a users, but it does not work.)


Finding parameters for $f(x) = x^2 + 2(m − a)x + 3am −2 = 0$ that satisfy a condition.

1.find a for $f(x) = x^2 + 2(m − a)x + 3am −2 = 0$ such that for every m real, f has real roots 2.find m such that for every a real, f has real roots  My ideea is to demonstrate that $\delta=4(m-a)^2 - 4(3am-2) = 4(m^2-5am+a^2+2) >0$ But I have no ideea how to do this.


I cant download not a thing on Ubuntu download center.I dont know my root password. Its always wants sudo password.And I cant write it(ı dont even know it though)  How can ı close or inactive it?


Tab sequence in Chrome when using Ctrl+Tab

When I use tabs in Chrome I want to switch back and forth between the latest use tabs.  The Internet Explorer Tab sequence was adjustable to use the "latest use" sequence.  So pressing Ctrl+Tab releasing the Ctrl key and pressing it again, returns me to the previous page. So Ctrl+Tab moves me always back in the sequence of the latest used tabs.  The advantage is obvious. I opened a new tab from the current page. And I just want to get back to the previous page. If I already opened 2 other tabs from this page. I have to press Shift+Ctrl+Tab 3 times to get back to the previous page.   I couldn't find any addin that brings me back this feature. Or is there any other trick or keyboard sequence to achieve this?  EDIT: The question was closed, but the provided link doesn't answer my question. I don't want a new hotkey. I want to cycle back in the latest used sequence with the existing keystroke. Most of the addins in the links provide an additional UI.


I'm using a convenience macro (\inputfigure[optional caption]{name}) to add plots created in tikz to my documents. My captions have been using adjectives (red or dashed line) to describe the parts of the plots but I think it would be nicer if I could use the markers instead using tikz within the caption. However, when trying I get errors that only occur when the graphic is passed as an argument to the caption (when testing the graphic in the main text it works as expected).  Depending on how I use tikz I get different errors. With the inline method:  \newcommand{\marker}[1]{\tikz \filldraw[#1] (0,0) circle (1.3pt);}   When \marker{red} is added to the caption (which is sent to \caption in the float environment) tex gives the following error:     ! Undefined control sequence.   \tikz@deactivatthings ->\def ;                           {\tikz@nonactivesemicolon }\def :{\tikz@nonact...       l.19 ^^I]{decisionPlot}   And when using the environment method:  \newcommand{\marker}[1]{%   \begin{tikzpicture}     \filldraw[#1] (0,0) circle (1.3pt);   \end{tikzpicture}}   I get:     ! Argument of @caption has an extra }.      < inserted text>            \par       l.22 ^^I]{decisionPlot}      I've run across a `}' that doesn't seem to match anything.   I can't find an extra '}' where I am and simply moving the \marker{red} outside of the caption resolves the error. I've also tried wrapping \marker in curly brackets but still get errors.  (Sorry, I'm struggling to get these block quotes right.)


Reaction while holding a readied action?

So when you hold an action using the Ready action you use your reaction to act when the trigger happens. however you're able to ignore the trigger. So while you are using the Ready action, are you able to take a DIFFERENT reaction before the trigger (or after if you ignored it) at the cost of losing the readied action?  Scenario: Fighter is fighting a bird and a goblin. The goblin is in melee range. The fighter readies a sword attack for when the bird comes into range. The goblin acts before the bird and leaves the fighter's range. Can the Fighter take an attack of opportunity - expending his reaction, and thus unreadying the attack on the bird?


Short story with stasis sleepers playing a game simulating history "in real time"

I am looking for a short story which I read as a kid, probably in the late 80ies / early 90ies. It's been a long time, but I'll try to describe it as I remember it.  In the story, the protagonist awakens from cryogenic (?) sleep. He is a successful player of a game simulating historical events which plays out in real time (think "civilization" but in real time); every couple of years, the players wake up, give orders, then go back to sleep. I think in the story, he is "playing italy", and in-game events take place in the 20th century, around the world wars. He is proud of being very successful doing that.  So one of his first orders is to "buy italy", presumably to get the right to play that nation. But to his shock, somebody else is already playing it, and that person is quite thoroughly unraveling everything he built up... I think in the finale, this other player is revealed to be his son or so.  Any hints as to the title and author of this story would be greatly appreciated.


I thought about it for a long time, but I can't come up some good ideas. I think that empty set has no elements,how to use the definition of an open set to prove the proposition. The definition of an open set: a set S in n-dimensional space is called open if all its points are interior points.


Multiple constructors: the Pythonic way?

I have a container class that holds data. When the container is created, there are different methods to pass data.   Pass a file which contains the data Pass the data directly via arguments Don't pass data; just create an empty container   In Java, I would create three constructors. Here's how it would look like if it were possible in Python:  class Container:      def __init__(self):         self.timestamp = 0         self.data = []         self.metadata = {}      def __init__(self, file):         f = file.open()         self.timestamp = f.get_timestamp()         self.data = f.get_data()         self.metadata = f.get_metadata()      def __init__(self, timestamp, data, metadata):         self.timestamp = timestamp         self.data = data         self.metadata = metadata   In Python, I see three obvious solutions, but none of them is pretty:  A: Using keyword arguments:  def __init__(self, **kwargs):     if 'file' in kwargs:         ...     elif 'timestamp' in kwargs and 'data' in kwargs and 'metadata' in kwargs:         ...     else:         ... create empty container   B: Using default arguments:  def __init__(self, file=None, timestamp=None, data=None, metadata=None):     if file:         ...     elif timestamp and data and metadata:         ...     else:         ... create empty container   C: Only provide constructor to create empty containers. Provide methods to fill containers with data from different sources.  def __init__(self):     self.timestamp = 0     self.data = []     self.metadata = {}  def add_data_from_file(file):     ...  def add_data(timestamp, data, metadata):     ...   Solutions A and B are basically the same. I don't like doing the if/else, especially since I have to check if all arguments required for this method were provided. A is a bit more flexible than B if the code is ever to be extended by a fourth method to add data.  Solution C seems to be the nicest, but the user has to know which method he requires. For example: he cant do c = Container(args) if he doesn't know what args is.  Whats the most Pythonic solution?


what types of hops can be grown in india ( in rajasthan sami arid zone)

I want to grow hops in Rajasthan (India).  How do I get seeds for hops in India?  Are there any companies in India that can provide me with what's necessary to grow my own?


Does there exist a surjective immersion $\mathbb{R}^2 \to \mathbb{R}^2$ which is not a diffeomorphism?  I tried to modify $\exp: \mathbb{C} \to \mathbb{C}$ to be surjective, but I find it hard to preserve the property of being immersion.  I also noticed that if we replace $\mathbb{R}^2$ with $S^2$ or any other compact simply connected manifold, no such immersion exists, because then it would be a covering map (as a local diffeomorphism from compact space, thus proper), but since the manifold is simply connected, it must be a diffeomorphism.


Helo there,   just a quick question, I'm using a pseudo-classical pattern to create objects in JS and I was wondering how do I actually create a private method that is accessible only inside the object.   let's say I want to add a private method XY() to object Animal. Does this kind of pattern allow me to create a private method?    function Animal(name) {   this.name = name }  Animal.prototype = {   canWalk: true,   sit: function() {     this.canWalk = false     alert(this.name + ' sits down.')   } }   Thanks in advance, Alex


Same pubkey allows access on one user, but not another

So I have a centos 7 server with 2 users.  User1 has the ~/.ssh/authorized_keys file with proper permissions and with externaluser's public key in it.  User2 has the ~/.ssh/authorized_keys file with proper permissions and with the same externaluser's public key in it.  Externaluser can ssh to User1 with no problems, however, he gets Permission denied (publickey,gssapi-keyex,gssapi-with-mic) error when trying to ssh to User2.  Why does this happen? It's literally the same public key, properly pasted into the authorized_keys file of each user, using the same method.


How do you show that a recurrence relation holds?

There's a problem that goes as follows:  Let $a_n$ be the number of binary strings of length $n$ in which there are no consecutive 0s. Show that $a_1 = 1, a_2 = 3$ and that $a_n = a_{n-1} + a_{n-2}$  I am not sure how exactly am I supposed to "show" the final bit. Proofs by induction involve the closed formula for $a_n$. Is there a formal, general proof to this or do I have to show using words and possibly figures?


Defining the format for Author misaligns the footnotes

I am working on my thesis (in french) and using Biblatex with  as the style for defining citations in the footnotes.  In addition to the normal footnotes (executed through \footnote{}), I am often using \footcite[][]{} to cite articles/books.  The geschichtsfrkl style adds a comma between the LastName and FirstName of authors. However, since my university asks that there must be no comma in between them, I updated the style using the following code:   \DeclareNameFormat{author}{ \nameparts{#1}% {\autorenschriftart% \ifdefvoid{\namepartprefix}{}{\namepartprefix\addspace}% \namepartfamily }% \ifdefvoid{\namepartgiven}{}{\space% \ifbool{bbx:nurinit}{\namepartgiveni}{\namepartgiven}}% \isdot% \ifthenelse{\value{listcount}<\value{liststop}}% {\autorentrennzeichen\addspace}{}% }%   But, doing so destroys the alignment of the footnotes and adds an extra space before the author name. Please check the following image for the problem (13 and 16 are citations and others are normal footnotes). I problem of alignment happens only with citations and not with normal footnotes.    I haven't so far managed to fix this problem. Any help would be greatly appreciated. Many thanks for help in advance :)  Following is a MWE:  \documentclass[     french,     10 pt,                   openright ]{article}               \usepackage[utf8]{inputenc} \usepackage[style=geschichtsfrkl, backend=biber, sorting=nyt]{biblatex}  \DeclareNameFormat{author}{ \nameparts{#1}% {\autorenschriftart% \ifdefvoid{\namepartprefix}{}{\namepartprefix\addspace}% \namepartfamily }% \ifdefvoid{\namepartgiven}{}{\space% \ifbool{bbx:nurinit}{\namepartgiveni}{\namepartgiven}}% \isdot% \ifthenelse{\value{listcount}<\value{liststop}}% {\autorentrennzeichen\addspace}{}% }%  \addbibresource{\thesis.bib} \usepackage{filecontents}  \begin{filecontents}{\thesis.bib}  @article{deroudille2019extraterritorialite,   title={L’extraterritorialit{\'e} du RGPD dans le contexte du “Cloud Act”},   author={Deroudille, Alexis and Fatah, Farid},   journal={Revue du marche commun et de l'Union Europ{\'e}enne},   number={630},   pages={442--452},   year={2019},   publisher={{\'E}ditions Techniques et Economiques} }  @article{decaux1987application,   title={L'application extraterritoriale du droit {\'e}conomique},   journal = {Cahiers du Centre de Droit International de Nanterre},   number = {3},   author={Decaux, Emmanuel},   year={1987},   publisher={JSTOR} }  @article{lehmann_m_legal_2017,     title = {Legal fragmentation, extraterritoriality and uncertainty in global financial regulation},     volume = {37},     issn = {0143-6503},     %language = {English},     number = {2},     journal = {Oxford Journal of Legal Studies},     author = {{Lehmann}, Matthias},     pages = {406-434},     year = {2017},     note = {OCLC: 7086651768},     pages = {406--434} }  \end{filecontents}  \begin{document}  Some text\footcite[Sample Pre-text][Post-text]{lehmann_m_legal_2017}, then some more text without pre- and post-notes\footcite[][]{decaux1987application}, and now a normal footnote\footnote{Hello world!}. One more citation just in case\footcite[][]{deroudille2019extraterritorialite}.  \end{document}


Does there exist an interval on the reals, however small, in which every number is irrational?

Since the irrationals are uncountably infinite, I've always imagined them "filling the space" between the rational numbers, but does that make sense? Or is it the case that any two irrational numbers has a rational number between them?


Prove or disprove: $ \mathbb{Q} \times \mathbb{Q[i]}$ is integral domain

Is $ \mathbb{Q} \times \mathbb{Q[i]}$ an integral domain ?  My attempt :  I know that  $ \mathbb{Q} \times   \mathbb{Q}$  is not integral domain take  $(0,1) \times (1,0) =( 0,0)$  But im confused in $ \mathbb{Q} \times \mathbb{Q[i]}$


How to use regex to replace a sentence that has a question mark

I am trying to write some code to translate Shakespearean English to Modern English but I'm having a problem using re.sub to replace sentences that end with a question mark. When I replace the sentence, I get 2 question marks at the end.  I've tried adding "\?" and "\?" to the substitute string but that does not work.   p = 'Mine eye hath played the painter and hath stelled. Thy beauty form in table of my heart; My body is the frame wherein this held, and perspective it is the painters art. For through the painter must you see his skill, to find where your true image pictured lies; Which in my bosoms shop is hanging still, that hath his windows glazed with thine eyes. Now see what good turns eyes for eyes have done. Have mine eyes have drawn thy shape, and thine for me? Are windows to my breast, where-through the sun delights to peep, to gaze therein on thee; Yet eyes this cunning want to grace their art; They draw but what they see, know not the heart.' s = 'Have mine eyes have drawn thy shape, and thine for me?' s2 = re.sub(r'^(.*?(mine.*?){0})mine', r'\1my', s) p = re.sub(s,s2,p) print(p)   Below is the output, which as you will note has 2 question marks at the end of the sentence I replaced.  Mine eye hath played the painter and hath stelled. Thy beauty form in table of my heart; My body is the frame wherein this held, and perspective it is the painters art. For through the painter must you see his skill, to find where your true image pictured lies; Which in my bosoms shop is hanging still, that hath his windows glazed with thine eyes. Now see what good turns eyes for eyes have done. Have my eyes have drawn thy shape, and thine for me?? Are windows to my breast, where-through the sun delights to peep, to gaze therein on thee; Yet eyes this cunning want to grace their art; They draw but what they see, know not the heart.


PDF of $(AB)^C$ where $A, B, C \sim U[0,1]$

Let $A$, $B$, $C$ be i.i.d uniform random variables on $(0,1)$.      What is the distribution of $(AB)^C$?   What is a good way to go about answering a question like this?  Trying to find the CDF of this distribution and then differentiating to find the PDF doesn't seem to be a particularly nice way to go about this problem.  Instead I have been trying to use  change of variables method (). In particular:  Let $X = A$, $Y = B$, $Z = (AB)^C$.  (So the inverse transformation is $A = X$, $B = Y$, $C = \frac{\log(Z)}{\log(XY)}$.)  Then, the joint probability distribution of $X$, $Y$, $Z$ is given by:  \begin{align} f_{X,Y,Z}(x,y,z) & = f_{A,B,C}(a(x),b(y),z(x,y,z))\cdot|\frac{\partial (a,b,c)}{\partial (x,y,z)}| \\ & = |\frac{\partial (a,b,c)}{\partial (x,y,z)}| \\ & = \frac{-1}{z \cdot \log(xy)} \\ \end{align}  In order to find the distribution of $Z$, I would now need to integrate this w.r.t x and y over $[0,\frac{z}{y}]\times[0,1]$:  $$f_Z(z) = \int_0^1 \int_0^{\frac{z}{y}} \frac{-1}{z \cdot \log(xy)} \,dx  \,dy \,\,\,\,\,\,\,\, (\text{for} \, z \in (0,1))$$  This is not easy (i.e. I don't know how to do this - maybe I am missing a trick as it is a (improper) definite integral?).  The issue seems to be: either I am going about this question in the wrong way, or, I am using the wrong change of variables. Indeed, since finding the distribution of Z using the change of variables method only involves integrating the Jacobian, using a different, more clever set of new variables may lead to a much nicer integral - I just have not been able to find such a set of variables.  Any help would be much appreciated.    Edit: In light of the comment below that the distribution of $(AB)^C$ is just $U[0,1$, it seems that a good way to go forward is to consider the MGF. (This did not originally seem like a particularly good option as I had guessed that the distribution would be somewhat esoteric, rather than a ‘known’ one.)    Note: Wolfram Alpha  that the integral of $\frac{-1}{\log(xy)}$ over $[0,1]^2$, for example is 1 - am I missing something obvious here?


when I want to fill 4 selected vertices to get a face to connect 2 different objects, the face gets weird shadows and I also can't sculpt the face. How can I remove these shadows and create a normal face ? :   video : file:///C:/Users/WIN10/Videos/Movavi%20Screen%20Recorder/ScreenRecorderProject130.mp4


Collect disk space metrics for whole SQL Server instance

I am quite new to SQL Server. I would like to collect database disk space metrics for the SQL Server instance as a whole.  I have found a code sample that can collect disk space information per database.  IF OBJECT_ID('DISK.dbo.disk_activity') IS NOT NULL     DROP TABLE disk_activity  CREATE TABLE disk_activity (        servername NVARCHAR(100)     ,  database_id INT PRIMARY KEY     , name NVARCHAR(MAX)     , data_used_size DECIMAL(18,2)     , log_used_size DECIMAL(18,2) )  DECLARE @SQL NVARCHAR(MAX)  SELECT @SQL = STUFF((     SELECT '     USE [' + d.name + ']     INSERT INTO DISK.dbo.disk_activity (servername, database_id, name, data_used_size, log_used_size)     SELECT           (SELECT @@SERVERNAME AS "Server Name") AS SERVER_NAME         , DB_ID()         , DB_NAME()         , SUM(CASE WHEN [type] = 0 THEN space_used END)         , SUM(CASE WHEN [type] = 1 THEN space_used END)     FROM (         SELECT s.[type], space_used = SUM(FILEPROPERTY(s.name, ''SpaceUsed'') * 8. / 1024)         FROM sys.database_files s         GROUP BY s.[type]     ) t;'     FROM sys.databases d     WHERE d.[state] = 0     FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 2, '')  EXEC sys.sp_executesql @SQL   However, I would like to collect the metrics across the entire server, i.e. total disk space allocated for all databases, total disk space used, total disk space free, and percentage of disk space used.  How should I modify the above script or are there other options available?


Why are two O(N) methods regarded as O(N)?

I have a method, in my program which calls two other methods that both have a linear time complexity. I don't know for sure if this would cause the method to have a time complexity if O(2N).  I know that constants drop off of time complexity which would make the method's time complexity O(N), but I am just not 100% sure. Can someone please elaborate on what a method like this would have for a time complexity and how?


When I was trying to update program and systme by Ubuntu softwar Center. Internet cut off and now I can not download any software to download Ubuntu Center and can not install  through Terminal? what can i do?


I am trying to build linux from scratch. I ll install it into virtualbox. Later I want to extract ext2 filesystem in it. Is it possible?  EDIT: I want to extract root.ext2 filesystem in vdi, to mount it in Ubuntu desktop environment and chroot into it.  EDIT2: moderators marked my topic as duplicate but it's not duplicate of above mentioned topic at all.  I found complete answer of my question. I post the link as a reference to people who seek the same answer:


Regarding self complementary trees if such exist.

Can anybody please tell me whether there are any self complementary trees and if so, how many and what are the conditions and the properties it holds? Thank You.


Suppose that I define two points a and b in a TikZ picture, such as:  \coordinate (a) at (.8,0); \coordinate (b) at (0,1.25);   And now suppose that I want to define a third point c whose first coordinate is the first coordinate of point a and whose second coordinate is the second coordinate of point b. Can it be done? And, if so, how?


How to shrink home partition on a running OS (Ubuntu linux)?

I want to reduce the home size. So I need to unmount it. How can I do it using gparted?  2) what type of file system is better for accessing both windows and linux.


My first time making Ciabatta...  Any ideas why my ciabatta is lacking air bubbles? It tastes nice and light.   It also didn’t rise as much as I’d expected.   I proofed airtight for 90 minutes then open air on a baking sheet for about 35 minutes.   I did notice the initial mix was really wet. Maybe a tad too much water I’m thinking?  Edit: Recipe - I halved it and followed it exactly.


Clicking button get NullPointerException in thread "AWT-EventQueue-0"

I`m trying to save entered in gui information in a text file.  The error I get is a   Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException   As I understand, when I click the OK button, the  button doesn't receive anything and that's why I get a nullPointerException. Where is a mistake?   Here is a JPanel class that manages JTextFields.   import java.awt.Container; import java.awt.GridLayout; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JTextField;   public class LibraryTextfieldsPanel extends JPanel{ private JTextField copyID; private JTextField ISBN; private JTextField author;   public LibraryTextfieldsPanel() {     this.setLayout(new GridLayout(3,1));     Container choiceBox = new Container();      this.add(new JLabel("Copy ID ")); copyID = new JTextField(); this.add(copyID);      this.add(new JLabel("ISBN ")); ISBN = new JTextField(); this.add(ISBN);      this.add(new JLabel("Author ")); author = new JTextField(); this.add(author);`enter code here`  }  public Integer getCopyID() {       try {           return Integer.valueOf(copyID.getText());       }       catch(NullPointerException ex) {           return 0;       }       catch(NumberFormatException ex2) {           return 0;       }     }   public Integer getISBN() {     try {           return Integer.valueOf(ISBN.getText());       }       catch(NullPointerException ex) {           return 0;       }       catch(NumberFormatException ex2) {           return 0;       }     }   public String getAuthor() {     return author.getText(); }   }  This is my Button Panel class that should receive the data from LibraryTextfieldsPanel.  import java.awt.FlowLayout; import java.awt.LayoutManager; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.File; import java.io.FileNotFoundException; import java.io.PrintWriter; import javax.swing.JButton; import javax.swing.JPanel;  public class OkButtonPanel extends JPanel { private JButton ok; private JButton cancel; private LibraryRadioPanel radioPanel; private LibraryTextfieldsPanel textFieldsPanel; private CategoriesPanel categories;   public OkButtonPanel(LibraryRadioPanel radioPanel, LibraryTextfieldsPanel textFieldsPanel,         CategoriesPanel categories) {     this.setLayout((LayoutManager) new FlowLayout(FlowLayout.RIGHT));     ok = new JButton("OK");     cancel = new JButton("CANCEL");     this.add(ok);     this.add(cancel);     this.radioPanel = radioPanel;     this.textFieldsPanel = textFieldsPanel;     this.categories = categories;      ok.addActionListener(new ButtonListener());     cancel.addActionListener(new ButtonListener()); }  private class ButtonListener implements ActionListener {       @Override     public void actionPerformed(ActionEvent arg0) {          JButton theButton = (JButton) arg0.getSource();          if (theButton == ok) {             Integer copyID = textFieldsPanel.getCopyID();             Integer  isbn = textFieldsPanel.getISBN();             String   author = textFieldsPanel.getAuthor();             try {                  PrintWriter out = new PrintWriter(new File("MyLibrary.txt"));                 out.append(copyID + " " + isbn + " "                         + author);                 out.close();             } catch (FileNotFoundException e) {                 System.out.println("File Not Found Exception");             }          }else if (theButton == cancel) {             textFieldsPanel.setVisible(false);          }     }  }   Thanks in advance


Why don't we see this special progressive 3x5 gear setup being offered?

This question is not the same as the 36 gear post which used a combination of internal hub gears, cogs, and chainrings.  This one is much simpler and much lower cost.  Part of the problem of something like a 1x15 (which doesn't exist) is chain misalignment.  However what about something like this to get 15 progressive gears with good chain alignment?  You have 5 cogs in the back, spanning a 1.75:1 range (28, 24, 21, 18, 16 for example).  However, instead of the typical triple front, have the fronts so they are 2x of the next smaller chainring.  For example, imagine something like 14, 28, and 56 front.  This would be most practical on something like a roadbike.  The 3 front chainrings would be aligned with the innermost, the middle, and the outmost cog.  Crosschaining would be moderate at most so nothing to worry about.  The idea here is you can start with the granny chainring, shift all 5 cogs, then go to the middle chainring and repeat all 5 cogs, then shift to largest chainring and shift all 5 cogs again.  That would give you 15 progressive gears without having to do any fancy interleaved shifting.  There is no way to get duplicate gear ratios here and the change between adjacent gear ratios is a reasonable 15%.  The range (spread) between lowest and highest gear would be 7 which is quite generous (lowest is 14/28 = 0.5 and highest is 56/16 = 3.5).  If someone wanted this biased more towards taller gearing that could easily be done.  So my question is why don't we see gearing like this on bikes when it makes good sense?  Even a child can grasp the simple concept of shifting thru all 5 cogs then go to the next larger chainring and repeat.  This concept can be tweaked to 3x4 for someone who wants wider gaps between gears and fewer gear ratios and to 3x6 for someone who wants narrower gear spacing and more gears (18 vs 15 vs 12 gears total).  If a 56 tooth front chainring is too large, we can go with 13, 26, and 52 instead and adjust the rear cogs to 26, 23, 20, 17, 15.  I think it would be fun to make a bike like this but I think the problem is the FD wont be able to handle that much difference in tooth ranges but if that is the only limiting factor, then perhaps a 2x5 or even a 2x6 with this same concept.  That would have a spread of about 4 which is good enough for a roadbike.  I actually checked this technique with my bike and if I change my granny chainring to 22 and keep my 42 large, it will work fine cuz when I shift from small/small, I don't then go to large/large cuz of the MegaRange gear I may eventually have.  I am actually temped to try it.  It would give me 13 progressive gears which beats a 1x11 in several ways.  1x11 has its advantages but well chosen sprockets in a 2x7 setup can beat it in other ways.  Changing my $100 bike to a 2x7 is much more cost effective than going to a 1x11 and I will have more range too.  Actually there is $0 cost if I just shift over the middle chainring (skipping it entirely but just using it as a "ramp" between the smallest and largest chainrings.


Get last result in interactive Python shell

In many symbolic math systems, such as Matlab or Mathematica, you can use a variable like Ans or % to retrieve the last computed value. Is there a similar facility in the Python shell?


Calculate least significant digit of large number with exponent

Let $x = 2017^{2017}$  How can I determine the least significant digit of $x$?  Can this be solved without using the Euler's totient theorem?


How to make 1 bit permanent memory circuit?

I would like to make a simple circuit to store or save 1 bit of data. The circuit should be able to remember the state of an LED ( on or off ) even if the supply is disconnected from the circuit. I need it to work like a hard drive, flash memory or SD memory card of cell phones.  I made a circuit as shown in the picture, The output is an LED in series with 470 ohm resistor. I use two bush buttons to charge or discharge the capacitor so the output LED is on or off.   After disconnecting the supply or turning off electricity, The circuit was able to remember the state of the LED for few minutes.   After 2 or 3 minutes, the capacitor discharged completely and the circuit lost its data.    How can I stop the capacitor from discharging ? or how can I slow the rate of discharging so that the circuit lose its data after a week or more ?  In this circuit I uses 555 as an inverter ( not gate ) but I may use any other IC's , My aim is just making a simple permanent memory.


Getting Error: exported bands must be compatible from Google Earth Engine

I'm trying to export a tiff map and gave the following error:     Error: Exported bands must have compatible data types; found   inconsistent types: Float64 and Float32.   How can I solve this?  Code:    //Choose country using GEE Feature Collection  var region = ee.FeatureCollection('ft:1tdSwUL7MVpOauSgRzqVTOwdfy17KDbw-1d9omPw').filterMetadata('Country', 'equals', 'Portugal');  //Add region outline to layer ‐ for selected countries  Map.addLayer(region,{}, 'Portugal');  // image collection pre 11/10/2017  var lt8_pre = ee.ImageCollection('LANDSAT/LC08/C01/T1_SR')   .filterBounds(region)    .filterDate(ee.Date("2017-08-01"),ee.Date("2017-10-11"));    Map.addLayer(lt8_pre, {bands: ['B4', 'B3', 'B2'],min: 1000, max: 1500}, 'image L8 pre');  var lt8_ndvi_pre = lt8_pre   .map(function(img){     return img.addBands(img.normalizedDifference(['B5', 'B4'])).updateMask(img.select(['pixel_qa']).neq(5).neq(3).neq(2));   });  // Create an NBR image using bands the nir and red bands (6 and 4) var lt8_nbr_pre = lt8_pre   .map(function(img){     return img.addBands(img.normalizedDifference(['B7', 'B4'])).updateMask(img.select(['pixel_qa']).neq(5).neq(3).neq(2));   });  print(lt8_ndvi_pre); print(lt8_nbr_pre);  // image collection pos 11/10/2017  var lt8_pos = ee.ImageCollection('LANDSAT/LC08/C01/T1_SR')   .filterBounds(region)    .filterDate(ee.Date("2017-10-18"),ee.Date("2018-02-10"));   Map.addLayer(lt8_pos, {bands: ['B4', 'B3', 'B2'], max: 1000}, 'image L8 pos');  var lt8_ndvi_pos = lt8_pos   .map(function(img){     return img.addBands(img.normalizedDifference(['B5', 'B4'])).updateMask(img.select(['pixel_qa']).neq(5).neq(3).neq(2));   });  // Create an NBR image using bands the nir and red bands (6 and 4)   var lt8_nbr_pos = lt8_pos   .map(function(img){     return img.addBands(img.normalizedDifference(['B7', 'B4'])).updateMask(img.select(['pixel_qa']).neq(5).neq(3).neq(2));   });   print(lt8_ndvi_pos); print(lt8_nbr_pos);  //Clip to Specified Region var NDVI_pre = lt8_ndvi_pre.mean().clip(region); var NDVI_pos = lt8_ndvi_pos.mean().clip(region); var NBR_pre = lt8_nbr_pre.mean().clip(region); var NBR_pos = lt8_nbr_pos.mean().clip(region);  Map.centerObject(region, 10); var ndvi_viz = {min:-0.8, max:1, palette:'000000,00FF00'}; Map.addLayer(NDVI_pre.select('nd'), ndvi_viz, "LT8 NDVI mean pre 11/10"); Map.addLayer(NDVI_pos.select('nd'), ndvi_viz, "LT8 NDVI mean pos 11/10");  // Display the NBRpost var nbr_viz = {min: -1, max:1, palette: ['FFFFFF','CC9966','CC9900','996600', '33CC00', '009900','006600','000000']}; Map.addLayer(NBR_pre.select('nd'), nbr_viz, "LT8 NBR mean pre 11/10"); Map.addLayer(NBR_pos.select('nd'), nbr_viz, "LT8 NBR mean pos 11/10");  //Calcule dNBR and dNDVI var dNBR = NBR_pre.subtract(NBR_pos); var dNDVI = NDVI_pre.subtract(NDVI_pos);   //Map.addLayer(dNBR,nbr_viz, "dNBR"); Map.addLayer(dNDVI.select('nd'), ndvi_viz, "LT8 dNDVI"); Map.addLayer(dNBR.select('nd'), nbr_viz, "LT8 dNBR");  Export.image.toDrive({       image: NBR_pos,       description: 'NBR_pos',       scale: 30,       region: Pt,       maxPixels: 278466375,     });


I'm using MySQL's AUTO_INCREMENT field and InnoDB to support transactions. I noticed when I rollback the transaction, the AUTO_INCREMENT field is not rollbacked? I found out that it was designed this way but are there any workarounds to this?


Make the site menu buttons adapt properly to half-screen size of FullHD resolution

Often enough I find myself snapping Stack Overflow or another SE site window to the left/right side of the 1920x1080 screen and have Visual Studio or SSMS on the other half, and the site doesn't look right at this width. Even though it's a pretty expected thing, in my opinion. FullHD resolution is pretty popular. It seems like the smallest width a page can be without starting to look weird is 1090 pixels. But in my case (Windows 7, so window borders and scrollbar are different from Windows 10) it's 925 pixels.  I remember there was a poll or a silent stats survey which has shown what the smallest resolution is, but I guess this use case wasn't taken into account.  The site's top menu buttons are clipped by the window size and there's a weird distance from the right side, approximately as wide as the scrollbar.    >>   I'm not asking to do anything about side widgets on the right, just the main menu strip buttons so that the "Ask question" button fits inside the window. Thanks.


How the crap do I display code on this site?

When I try to put in my code snippets it never works. If I press space 4 times, it only monotypes the first line after I paste in my code. No freaking way are we supposed to go in and put 4 spaces on ever line??


I hope that can I get family reunion visa for Germany after I'm banned from Slovenia for six months because of expired passport while going to Austria

I am a Nigerian. I live in Croatia and my wife, a Croatia citizen, lives and works in Germany. Recently I was caught with my expired passport by Slovenia police while going to Austria to renew my passport and they issued me six months ban from Slovenia and now I want to apply for a German family reunion visa to join my wife in Germany. Will the ban affect my family reunion visa?


Does a Nikon DX lens on a FX camera get subjected to the 1.5X crop factor?

My friend has a Nikon 35mm DX lens that I want to use on my FX camera. If I use his lens on my camera in DX mode, does the effective focal length of the lens become 35mm * 1.5 = 52.5mm, or does it just take a crop of the center with an effective focal length of 35mm?


Show that $\sigma\circ\phi : G_1 \to G_3$ is an isomorphism

Let $G_1, G_2$ and $G_3$ be groups.  Let $\phi: G_1 \to G_2$ and $\sigma: G_2 \to G_3$ be isomorphisms of groups.  Show that $$\sigma\circ\phi: G_1 \to G_3$$ is an isomorphism.  I understand to prove the composition is a homomorphism (operation preserving) and a bijection.  I need help with notation and how to show the operation preserving, onto and one-to-one.  Operation preserving:  $\sigma\circ\phi(ab)=\sigma(\phi(ab))=\sigma(\phi(a)\phi(b))=(\sigma\circ\phi(a))(\sigma\circ\phi(b))$  Am I on the right track?


I am trying to solve the following exercise  Show that $S_n$ has no subgroup of index $t$ for $2 < t < n$  which is the exercise 3.25 of , by Joseph J. Rotman. I think I should use a theorem that says that if $H \le G$ and $[G : H] = \ell$, then $\exists \rho \in \mathrm{Hom}(G, S_\ell)$ such that $\ker(\rho) \le H$.  That would give me an isomorphism between $S_n / \langle \ker(\rho) \rangle $ and $\mathrm{Im}(\rho) \le S_t$ and I was hoping to prove that it is impossible. I tried to fix some value for $t$, for instance, $t = 3$, to have some idea about the general problem, but even in this scenario, I am not able to prove it, because I can't visualize the group $S_n / \langle \ker(\rho) \rangle $. Well, do you have any tip? I am not looking for a full answer to that exercise, but maybe you could point out some theorems and properties of $S_n$ that might be useful here.


Let $(X, d)$ be metric space. Define $B_\epsilon = \{ x \in X : \exists b \in B \; d(x, b) \le \epsilon\} $. Let $F(X)$ be a family of all nonempty compact subsets of $X$ (so $\emptyset \notin F(X)$ ). We shall define Hausdorff metric by: \begin{equation}   D(A, B) = \inf \{ \epsilon \in \mathbb{R}^+ : A \subset B_\epsilon \; \land B \subset A_\epsilon \}. \end{equation} Then $(F(X), D)$ is a metric space.  What I would like to know is what is the relation between connectedness of $(X, d)$ and connectedness of $(F(X), D)$.  So far I was able to prove that if $(X, d)$ is not connected, then $(F(X), D)$ also is not connected. Here the main idea was that if (A, B) is a pair of nonempty subsets of $X$ such that $A\cup B = X$ and $A \cap B = \emptyset$ and $A, B$ are open, then $(2^A \cap F(X), F(X) \setminus 2^A \cap F(X))$ is a pair of nonempty, open subsets of $F(X)$ which sum to $F(X)$ and have empty intersection. (Which by contraposition means that connectedness of $(F(X), D)$ implies connectedness of $(X, d)$).  Is the opposite implication true, that is, does connectedness of $(X, d)$ imply connectedness of $(F(X), D)$?


I created a software, and now I want to make software public.If ysers will type on terminal command   apt-get install printx   then software will installed on their pc, and updated ~/.bashrc file.  How can I do it ?   Thank you.


How can I limit battery charging to 80% capacity?

I just learned that some Lenovo laptops include a utility that offers to limit battery charging capacity to within 0–80% in order to slow the attenuation of the battery lifespan:    How can I do this in Ubuntu?


Vist US for 90 days ( VWP), leave and return for 70 more days; is that a problem?

I'm an Australian citizen who, after graduation, wants to spend 6 months travelling, most of that in US, and return for a graduate job in Australia after that 6 months.  My plan was to use the Visa Waiver Program to enter for the first 90 days, then after that's up, either return to Australia or explore the UK for a couple of weeks, and then return to the US.    Since I do not know where I will go, either AUS or the UK, until nearer the end of the time in the US, I plan on buying a one-way ticket to the US; will that raise red flags? Will I have any issues upon return to the US, after a couple of weeks spent  in either AUS or the UK?   A good note from some of the other questions I've read is that I do not have a significant other in the US, nor any family. And I have very tangible motivations to return to Australia for my graduate job.


I saw a sentence  She hoped to have done  Or a sentence, created with the same structure. I don'tunderstand how it works. Then I saw a full version of it:  She hoped that she had done  So, it's like a combination of Past Simple(hoped) + Past Perfect(had done) but combining them we can't have Past Perfect, we have  only perfect infinitive.  When I later saw  She can't have done  I didn't understand it, too. Since then I've been trying to create a full version of it which would be clear for me. I tried  It can't be possible that she has done - I was told it was incorrect  It can't be true that she has done - I was told it was incorrect, too  I also have such variants:  It can't be real that she has done  There can't be a possibility that she has done it  There can't be a probability that she has done it  Is there any sentence among those I wrote which can be equaled to "She can't have done"?


Can I fire `override` method in parent and grand-parent classes of base "virtual" method

i.e. I have 2-step inherited class, and have access  only Parent_1 class:  public class Base {     public virtual void hello (){} }  // public class Parent_1 : Base {     public override void hello (){ Print("Hi 1"); } }  public class Parent_2 : Parent_1 {      public override void hello (){ Print("Hi 2");  xyz =123; }  }   I don't have access to any code other than Parent_1. I want, when Parent_2's hello is executed, my Parent_1's hello was also fired.    I think there should exist some way, so when Parent_2 is executed, somehow I got notified (event handler or whatever) in Parent_1 , is not that possible?  I know xyz is "changed" there, so maybe a "property change observer" ?


Isn't the whole historic Discussion of Heliocentric vs. Geocentric Worldview just about a Calculation-Technique. I mean I could also choose my coordinate-center to be in the middle of Earth and setup my differential Equations and starting points and it would still describe all Movements correctly, right?  Now if I want to solve this it might be pretty wise to choose the Sun as my coordinate origin. But nevertheless I could transform the resulting curve so that the origin is within earth and I can claim that the Sun is (in a fancy possibly self-intersecting way) rotating around Earth, and even the whole Universe is ( in a very fancy way) rotating around the Earth.  What's the Problem here? Isn't this the General Principle of Relativity in Physics?  How do we have to define Rotation, so that we get the Heliocentric Worldview? If we don't allow self-intersections, we would get a Problem with double-star-systems and Planets which rotate around both stars.  It seems that the current Definition relies on the Masses of the involved Objects. But this seems to be a very naive View neglecting the Fact that Forces aren't imposed by the "stronger" Object ( = Human Intuition) but that they are just caused by "Physics itself".


30x Optical Zoom vs. 30x Magnification on Binoculars?

I just recently learned that 30x Optical Zoom on a Camera and 30x Magnification on Binoculars are different things.  Suppose if I have got 30x50 Binoculars, then what would be its equivalent number of an Optical Zoom that I can expect?


Does casting Web interrupt the spell Sanctuary?

Does casting  interrupt the spell  on the caster? If yes, in which moment? Let us consider the case in which there is an enemy creature in the area covered by the web.  Maybe it can be useful underline a couple of things:    When web is cast, no creatures are affected. A creature will be affected by the web if it is starting/going through its turn there and fails the saving throw. About sanctuary: if the warded creature makes an attack or casts a spell that affects an enemy creature, this spell ends.


Let $W_t$ be a one-dimensional Brownian motion and I would like to prove  $$\lim_{\beta\rightarrow+\infty}\sup_{0\leq t\leq T}\left|e^{-\beta t} \int_0^te^{\beta s}\mathrm dW_s\right|=0$$  This is an exercise in Chapter 3 of Karatzas&Shreve, but I don't think this proposition is true since  $$\sup_{0\leq t\leq T}\left|e^{-\beta t} \int_0^te^{\beta s}\mathrm dW_s\right|\geq \left|e^{-\beta T} \int_0^Te^{\beta s}\mathrm dW_s\right|:=|G|$$  where $G$ is a centered Gaussian random variable of variance $(1-e^{-2\beta T})/2\beta$, which implies the precedent proposition can not be true. Could someone tell me where I am wrong or this proposition is not true? Thanks a lot


Is it possible to see what license an individual song has on Soundcloud? Some of the songs have Creative Commons but others appear to not have any license.


I recently updated my Ubuntu to 15.04 and now I'm back to Unity shell. The gnome-shell I had became buggy after the update, so I had to revert back. How do I get a Gnome shell (again) without switching to Ubuntu Gnome? I really can't afford to do a reformat right now.


Dependency issues while installing PacketTracer

I couldn't install PacketTracer on my Ubuntu 20.04 using sudo dpkg -i PacketTracer_730_amd64.deb command.


The message "Community♦ reviewed this ...: Approve" in suggested edits

I've noticed that the message above appears sometimes when I choose "Improve" in the suggested edit review queue, as .  Given that the Community approval and my edit have the same time stamp, I believe this is an automated process.  , the suggest edit had 3 approve votes (by real users) prior to my edit, so the Community notice did not appear.  Could someone please clarify what is going on?


How to round a float number in Java if its a whole?

How do I round a float number if it returns a whole value? And, how do I round if it's like: 5/2 = 2.5  and NOT like this: 5/2 = 2.50000000


How to determine the product key from the console for Windows 10?

On a Surface 3 tablet, how do I determine, from the console, the product key for Windows 10?  Microsoft says:     Product keys for Windows      A product key is a 25-character code that's used to activate Windows   and helps verify that Windows hasn't been used on more PCs than the   Microsoft Software License Terms allow. Windows 10: In most cases,   Windows 10 activates automatically using a digital license and doesn’t   require you to enter a product key. However, if a product key is   required, it can usually be found in the confirmation email you   received after purchasing Windows, or in the box Windows came in.   Microsoft doesn't keep a record of purchased product keys—visit the   Microsoft Support site to learn more about activating Windows 10.   Some initial googling suggests:  ********************** Windows PowerShell transcript start Start time: 20200412065627 Username: DESKTOP-9AKB65V\thufir RunAs User: DESKTOP-9AKB65V\thufir Configuration Name:  Machine: DESKTOP-9AKB65V (Microsoft Windows NT 10.0.18362.0) Host Application: C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe Process ID: 27096 PSVersion: 5.1.18362.628 PSEdition: Desktop PSCompatibleVersions: 1.0, 2.0, 3.0, 4.0, 5.0, 5.1.18362.628 BuildVersion: 10.0.18362.628 CLRVersion: 4.0.30319.42000 WSManStackVersion: 3.0 PSRemotingProtocolVersion: 2.3 SerializationVersion: 1.1.0.1 ********************** Transcript started, output file is key PS C:\Users\thufir> winver PS C:\Users\thufir> wmic path softwarelicensingservice get OA3xOriginalProductKey OA3xOriginalProductKey XXXXXXXXXXXXXXXXXX PS C:\Users\thufir> cmd Microsoft Windows [Version 10.0.18362.720] (c) 2019 Microsoft Corporation. All rights reserved.  C:\Users\thufir> C:\Users\thufir>slui.exe  C:\Users\thufir> C:\Users\thufir>exit PS C:\Users\thufir> stop-transcript ********************** Windows PowerShell transcript end End time: 20200412065743 **********************   firstly, is that above key valid?  Or, rather, how would I determine its validity?  see also:


Claim: Let $V$ be a vector space over $C $ .   (V may not be finite dimensional vector space).  Let $T: V \to V $ be a linear transformation.  if $\lambda = 0 $ is $T$'s only eigenvalue than $T$ is nilpotent.  I'm not sure about this claim. I think it's not true, but couldn't find a counter example.  Thanks for helping !


How to test whether we are sending data properly to WSDL?

I want to know how to test or know that we are sending data in WSDL in a proper manner. I know that if we are creating a web service we can test easily with SOAP UI or other tools, but how do I test with when I am consuming the web service. Thanks in Advance


Find the probability a bag contains m nails

A worker carries two bags. Each of the bags initially contains N nails. Whenever the worker needs a nail, he takes it from a bag picked at random. At some point the worker picks an empty bag. Find the probability that the other bag contains exactly m nails.


Inequality $\sqrt{1+x^2}+\sqrt{1+y^2}+\sqrt{1+z^2} \le \sqrt{2}(x+y+z)$

If $x>0$, $y>0$, $z>0$ and $xyz = 1$ then   $$\sqrt{1+x^2}+\sqrt{1+y^2}+\sqrt{1+z^2} \le \sqrt{2}(x+y+z)$$   I tried using $\displaystyle x = \frac{a}{b},y = \frac{b}{c}$ and $\displaystyle z = \frac{c}{a}$ substitution,  $\displaystyle \sum_{cyc} \frac{\sqrt{a^2+b^2}}{b} \le \sqrt{2}\left(\frac{a}{b}+\frac{b}{c}+\frac{c}{a}\right) \\ \displaystyle  \iff 6+ 2\sum_{cyc}\frac{\sqrt{(a^2+b^2)(b^2+c^2)}}{bc} \le \sum_{cyc}\frac{a^2+b^2}{b^2} + 4\sum_{cyc}\frac{b}{a}$  So it would suffice if we showed $\displaystyle \sum_{cyc}\frac{\sqrt{(a^2+b^2)(b^2+c^2)}}{bc} \le 2\sum_{cyc}\frac{b}{a}$  Squaring again does not lead anywhere nice. Is the last inequality true ? If not is there a better way of showing the result ?


System requirements for Ubuntu installation

I am new to ubuntu. I am having a PC with Pentium 4 processor 512 MB ram and an  inbuilt graphics card. Can I install Ubuntu on my system? Right now I am having Windows XP. But it is somehow corrupted. Please help. How can I install Ubuntu on my system? Will it work fine with my system specifications?