How can I encourage my players to learn the rules themselves?

Background: I have been DM'ing a table for close to a year where we play around 3 times a month. The majority of my players are new to role-playing games and DnD 5th edition. All of them came to me and asked if I would teach them the game and DM for the table. We first played a level 1-5 campaign where we fought basic enemies, did light dungeon exploring, and interacted with NPCs. At first, they were really engaged and excited about learning their character abilities and the rules of the game. They really wanted to level up fast so they could get more powerful, but I wanted to make sure they could grasp their characters at the current level before adding more complexity too fast. We later changed settings of the campaign and they continued to level their characters, eventually ending at level 9. After a few months, it seemed that all of my players started to forget even the basics of combat and skill checks. Though they still seemed really engaged in the story, they seemed to lose interest in the mechanics of the game. Combat started to take longer, because I'd have to stop and explain their skills and abilities, which in turn makes other less engaged - compounding the problem. When I DM, we typically play theater of the mind, but I bring out a map and miniatures for combats to help players see how many enemies are in play and where everyone is. I find this helps people stay engaged. I really don't use any homebrew rules, though I do sometimes handwave some of the more annoying rules (distance, changing weapons) to keep combat flowing. (e.g. "Am I close enough to attack?" "Sure, you can reach that enemy"). We also have access to all the books on DnDBeyond by sharing with a subscription so access to the rules isn't an issue. What I tried:  When we created characters, I sat down with each of the new players and we talked through each of their classes features, what their 'bread-and-butter' turn in combat should look like and how they can combine their abilities to make some strong plays. I helped my players create cheat-sheets that had their go-to abilities, attacks, and spells to help remind them of what their class and characters are best at doing. I frequently reminded players before our sessions to review their spells and features so they understood them. I would do some post-combat analysis with players that took relatively inefficient turns and suggested ways they could have played that turn differently. If players attempted to take extra actions, or do things against the rules, I would give them simple reminders like, "Remember, you get to take one action, one bonus action, and you get to move" When my players are confused about a rule, I explain it to them, and they seem to understand just fine for the rest of the session. Though, they often forget between sessions and I need to re-explain it the next week  Things even as simple as skill checks will have the players asking, "Wait, how do I do that again?". At this point, I'm getting tired of having to keep track of all of my monsters turns and abilities as well as the players. It's really just too draining to juggle the mechanics for everyone and tell an engaging story. I'm really considering that TTRPGs just aren't the game for these players. How can I better encourage my players to learn the rules and their character's abilities?


Show Google results along with related questions

A significant number of downvotes are given to questions whose askers didn't first check Google. This seems to be closely related to downvotes from asking a question with duplicates in the "Related Questions" field. How about also showing Google's "I'm feeling lucky," or some other results, in the Related Questions to help out with that?   EDIT: to clarify, I'm not talking about questions with answers on Stack Overflow, but rather questions with easy solutions available via Google. Here's a question just like that:


Prove that the symmetric group $S_n$, $n \geq 3$, has trivial center.

I am trying to prove this:  Let $\sigma$ be a non-identity element of $S_{n}$. If $n \geq 3$ show that $\exists \gamma \in  S_{n}$ such that $\sigma\gamma \neq \gamma\sigma$. Hint: Let $\sigma*k=1$ where $k \neq 1$. Let $m$ not be an element of $\{k,1\}$. Let $\gamma=(k,m)$  Here's the answer from the textbook: Let $\sigma*k=1$ for some $k \neq 1$. Then as $m\geq 3$, choose an $m$ not an element of $\{k,1\}$. Now let $\gamma=(k,m)$. This gives $\gamma*\sigma*k=\gamma*(1)=1$ but $\sigma*\gamma*k=\sigma*m \neq 1$, since if $\sigma*m=1=\sigma*k$, then $m=k$, as $\sigma$ is one-to-one contrary to the assumption. I guess I'm just not understanding the steps to their proof. Can anybody make sense of this to someone new to proofs? I mostly don't understand how $\sigma*\gamma*k=\sigma*m=1$


Can we cool a room by opening the door of a refrigerator?

The room cools for a moment but then it becomes warmer. Why?


How do you performance test JavaScript code?

CPU Cycles, Memory Usage, Execution Time, etc.?  Added: Is there a quantitative way of testing performance in JavaScript besides just perception of how fast the code runs?


How does one become a deity? I read Deities and Demigods, but some things are either not explained or not mentioned at all.   Do you have to get a blessing from a god with 20+ divinity? Can you achieve ascendancy with a lot of worshipers? (Let's say a million.) Can you ascend if you kill a god? Is there a ritual to become a god? Any other means of becoming a god?


Windows 8.1 Pro: Why does the name of the home folder end with _000?

I just re-installed Windows 8.1 Pro and I noticed something strange about my home directory folder C:\Users\Username. The name of the folder instead of being Username is Usernam_000 C:\Users\Usernam_000. Why is that? Is this normal behavior? If not how can I change its name?  Edit 1:  As I have said in a comment all of these answers in the questions you provided as duplicates just say ways of changing the name. My principal question is why this happened. I want a way to change the name only if it is a normal situation and not a problem.  Edit 2:  As I am really curious about this "problem" I did another installation of Windows 8.1. The same thing happened again, although I deleted the partition and formatted it again.


In Quantum Physics would a camera count an observer that causes wave collapse?

Would the observation from a camera have the same effect on wave function as the observation from a living being?


Q: Commutator subgroup of free group of infinite rank

I know that $\ F_n$/[$\ F_n$,$\ F_n$] is isomorphic to $\Bbb Z^n$, but I do not know what happens if the rank is infinite. In particular, if the rank is countable, is the resulting group isomorphic to the direct sum or product of countable many $\Bbb Z$s? And what happens if the rank is uncountable?


Recover Hard Disk from accidentally formate in ubuntu installation

I am very new to ubuntu. During ubuntu installtion, I choose an option that allow ubuntu (12.10) to replace my window 7 without knowing that it will formate and repartition my hard disk. Then, all my important files are gone.  Could you please tell me how can I get my files back? or if possible, Could i recover all partition back?  Your help will be appreciated.


What's the difference in the meaning between "you could say" and "you would say"? when something is in specific context and If that (something) is usual, we use would instead of could? I'm not sure but I think "you would say" is used to speculate, imagin something or instead of may/might and "you could say" is used to refer the possibility of happening something or to give suggestion. I'm quite a bit stuck in the meaning of "you would say", could you please interpret its meaning and in which situations or context it's ("you would say") used?  For some example:  1.You would say "I wished I had been back..." in a suitable context. 2.If you never drink a cup of tea in the morning, you would say "I never drink a cup of tea in the morning" 3.If you Speak English well, you would say "I'm a native speaker of English."


I'd like to do a health check of a service by calling a specific url on it. Feels like the simplest solution would be to use cron to do the check every minute or so. In case of errors, cron sends me an email.   I tried using cUrl for this but I can't get it to output messages only on errors. If I try to direct output to /dev/null, it prints out progress report.    % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current                                  Dload  Upload   Total   Spent    Left  Speed 100  5559  100  5559    0     0   100k      0 --:--:-- --:--:-- --:--:--  106k   I tried looking through the curl options but I just can't find anything to suit the situation where you want it to be silent on success but make noise on errors.  Is there a way to make curl do what I want or is there some other tool I should be looking at?


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If i had 2 eggs. 1 i boil in plain water. The other i boil in say a curry sauce. After boiling and peeling, would they taste different to one another?   Do the shells let any flavour through?


my problem is, that I always get a nullpointerexception in my retrofit request, but I have no idea why...  Feedis a own created class which should contain the response from the retrofit request.  ServiceAPI:  @GET("top-headlines?country=de&apiKey=xxx") Call<Feed> getNewsFeed();   Retrofit-Call in onCreateView:  Retrofit retrofitNewsData = new Retrofit.Builder()             .baseUrl(NetworkService.NEWS_DATA_BASE_URL)             .addConverterFactory(GsonConverterFactory.create())             .build();      Log.d(TAG, "network service connected to: " + retrofitNewsData);      ServiceRepository serviceRepositoryNewsData = retrofitNewsData.create(ServiceRepository.class);      Call<Feed> callNews = serviceRepositoryNewsData.getNewsFeed();     callNews.enqueue(new Callback<Feed>() {         @Override         public void onResponse(Call<Feed> call, Response<Feed> response) {              newsFeed = response.body();             Log.d(TAG, "Habe den feed: " + newsFeed + " erhalten." + response.code());         }          @Override         public void onFailure(Call<Feed> call, Throwable t) {          }     });`   Base-URL: public static final String NEWS_DATA_BASE_URL = "https://newsapi.org/v2/";


Finding $\min f(x)$ where $f(x)=\int_0^1 |t-x|t\,dt \quad \forall x \in \mathbb{R}$

Can I write the integral as $f(x)=\int_0^{x} |t-x|t\,dt + \int_{x}^1  |t-x|t\,dt$  so that $f(x)=\frac{2x^3-x}{2}+\frac{1-2x^3}{3}$  But here I'm restricting $x$ to the interval $(0,1)$ and I need $x$ to be any real number.   So what should be the correct approach here to find the minimum value of $f$?


This is the most interesting thing I have seen! I have built a  that sends data (D0-D7) to a DAC (ADV2175). The design worked fine and I just have a low frequency alias noise (). This noise was present on all my ground planes (This is in prototyping stage and that's not unexpected from the test PCB).  I started tracing the noise path by disconnecting wires to see when the noise is gone. Surprisingly even after disconnecting all VCC and GND connections (+ all VREF and logics gone to 0 or 1) the noise was present yet. The more unexpected behavior is when the DAC is just connected to DATA port+ CLK pin (all coming from the source FPGA, NO VCC or GND), it continues working and a sine wave is produced (but with the same noise)!!!  First I thought it may receive its VCC/GND form the logic 1/0 fed into it but if it was correct, it should not have produce 0x00 and 0xFF levels, but it makes those levels correctly (I changed 0xFF data stage to another level and a notch appeared on top of the waves. this shows it can build oxFF correctly).    This is a big challenge for my PCB design, as if this device really takes its GND from the data port, instead of the dedicated pins, I will have a hard time for designing a reliable ground plane for it (the return voltage should go back to a logic noisy environment and analog-digital ground plane isolation may be impossible).  Can anyone explain what is happening there?


"The only thing bringing any money into that floating city IS tourists" Is this grammatically correct? Is there ever a time when one could us "is" for a plural?


Non-compactness of $\mathbb{R}$ with the cocountable topology

Is $(\mathbb{R},\tau_{co})$ compact where $\tau_{co}$ is the cocountable topology on $\mathbb{R}$?  I have the answer of my teacher but I'd like to see another one so I can understand better how people find the answer intuitively. He says:     $\mathbb{N}-\{n\}$ is infinite countable for all $n\in\mathbb{N}$.   Then $V_n = \mathbb{R}-(\mathbb{N}-\{n\})=(\mathbb{R}-\mathbb{N})\cup\{n\}\in\tau_{co}$ for all $n\in\mathbb{N}$.      Then $U=\{ V_n : n\in\mathbb{N}\}$ is a open covering of $(\mathbb{R},\tau_{co})$.      $U$ does not contain a countable subcover since $V_n\cap\mathbb{N}=\{n\}$ for each $n\in\mathbb{N}$ and $\mathbb{N}$ is infinite.   How would you solve that problem?


Don't worry, I have written your name on the attendance sheet.   Or     Don't worry, I wrote your name on the attendance sheet.


Why do we say "You are" when you is singular instead of "You is"?

The title really says it all. Since "you" can be singular or plural, why don't we say, "You is" when using "you" as singular? We say "he is" or "they are". Why is it different?


Infinite product $ \prod^{\infty}_{n=0}\left(1-\frac{1}{2^{3n}}-\frac{1}{2^{6n}}\right)$

Find the value of the following expression  $$ \prod^{\infty}_{n=0}\left(1-\frac{1}{2^{3n}}-\frac{1}{2^{6n}}\right)$$   What I tried:  If $\frac{1}{2^3}=x$, then we can write expression as   $$\prod^{\infty}_{n=0}(1-x^n-x^{2n})=(1-1+1)(1-x-x^2)(1-x^2-x^4)(1-x^3-x^6)\cdots$$  How do I find that infinite product?


MWE:  \documentclass{article} \usepackage{tikz} \usetikzlibrary{positioning} \begin{document} \begin{tikzpicture} \node (x) {X}; \node[above right=1mm and 2mm of x] (y) {Y};  \draw[double,double distance=2mm] (x) -- (y); \end{tikzpicture} \end{document}     How to remove the thin lines?


Ubuntu installation issues on Dell Inspiron 15 i7559

I have been trying to setup a dual boot on my laptop, I can't seem to get much past the install.  In order to start the install I need to pass nomodeset i915_bpo.nomodset=1 in grub. After the install 9 out of the last 10 tries (yes I have reinstalled 10 times, minimum) it will hang during boot. The 1 time it booted, I tried to follow a guide made installing Ubuntu on this specific model and essentially after setting up the Nvidia drivers it decides to take a dump again and I can't even get it to boot.  Can anyone give a last minute suggestion before I give this one last shot?  I would prefer Ubuntu GNOME, but I guess anything that will let me get a fully operational system would be great. I have been trying with 16.04 and 16.10, if there is another version I can try for the initial install then I will give it a roll.


How do I install Java, including in my browser, so websites with Java work?


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Definition: A topological space $X$ is called Hausdorff  space if for each $x_1,x_2 \in X$ (they are distinct) we can always find neighborhoods $U_1,U_2$ of $x_1,x_2$  such that $U_1 \cap U_2 = \varnothing $.  Is this definition equivalent to say that the following set   $$ \mathcal{D}  = \{ (x,x) : x \in X \}$$  is closed in $X \times X $ ??  Im having difficulties seeing why this istrue. Any help would be greatly appreciated.


I am writing a document for which I need the margin to be exactly as follows: left, right, top and bottom text margin all equal to 1in, distance from bottom of the paper to page number equal to 0.75in (I don't have any footnote or header to set).  I tried to use the fullpage package in LaTeX but it does not give me the 0.75in to the page number. Is there a way to force that? I tried to set manually the margins for a 8.5x11 paper but I am not succeeding.    I tried but after writing:  \documentclass[PhD]{class_file} \usepackage[margin=1in,footskip=0.25in]{geometry}   I get the error message \paperwidth (0.0pt) too short.  I don't see the \paperwidth is set to 0.0pt anywhere though..  Also it seems to me that depending on which machine I use to compile my tex file, I get different margins, even when I set them up manually (without using geometry). Is it possible?    Using the geometry package things seem to work a bit better now (I changed machine and the problem with the paper width previously mentioned disappeared).   \usepackage[margin=1in,footskip=0.25in]{geometry}   gives me without problem upper, right and left margin of 1in. But the lower margin is 1.2in and I can't change it to be 1in even by using bottom=1in or bottom=0.8in. I really don't see how this can happen. Maybe a problem with the spacing between lines? The class files I am using can be fund at   I erased the margin settings of uclath12.clo as the margin I need are different from the ones that this file gives. Thank you.


Is there a program to convert assembly to C++?

Is there a program that will convert assembly to C or C++? I did a lot of searching but I could not find anything that works. There is a program called "Boomerang"; it looks great and just want I wanted, but it's very unstable and crashes when I try to use it. ()  Are there any other free programs that will do that?


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Let $\phi$ be a misurable function in [0,1] such that the linear trasformation $A\colon f\to \phi*f$ maps $L^2[0,1]$ in $L^2[0,1]$.Prove that $\phi\in L^{\infty}[0,1]$. Calculate t e norm of the operator A. When A is surjectiv,invertible,the inverse of A is continous?


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Recently  in last 15 days we have started loosing number one ranking in large number of keywords to our competitors. Probably it can be because of recent core web vitals release by google. Not sure.  Here are my findings  My site on those keywords is ahead by 20 to 30 points in overall page performance based on these  web vitals(FCP, SI, LCP, TTI, TBT, CLS) On three core web vitals i.e. LCP, CLS , FID   we are behind in LCP and CLS than our competitor , they are green we are orange, On FID both are green  Can it be right hypothesis that lost in ranking can be because of recent core web vital release where we are behind on LCP and CLS though we are much better on overall page score(based on all six web vitals) ?


Let $A$ be the set of all rational numbers $p$ such that $p^2<2$, and let $B$ be the set of all rational numbers $p$ such that $p^2>2$. It can be shown that $A$ has no largest element and that $B$ has no smallest element by associating  to each $p>0$ the number $$q=p-\frac{p^2-2}{p+2}$$  and then proving that $p\in A \Rightarrow q\in A$ and $p\in B\Rightarrow q\in B$.   Where is this value of $q$ coming from?


Whenever I try and label an equation in the following format  \begin{equation}\label{eq:blah} blah \end{equation}   and then reference this equation  By \eqref{eq:blah}   I get the usual (??) of an ill-defined labeling. It only happens with equation environments though.  I've tried removing almost everything I can think of in my preamble to make it work, but to no avail.   Consequently, I am posting a MWE which is not very minimal—apologies!  Any help is greatly appreciated!  \documentclass{book}   \usepackage{amsfonts,amssymb,latexsym,verbatim,url,color,mathrsfs,tikz,extarrows,enumerate,lipsum,mathtools} \usepackage[nameinlink]{cleveref} \usepackage{enumerate,fancyhdr,verbatim,comment}  \usepackage{dsfont}   \usetikzlibrary{matrix,arrows}   \usepackage[colorlinks = true,             linkcolor = blue,             urlcolor  = blue,             citecolor = blue,             anchorcolor = blue]{hyperref}     \usepackage[amsmath,thmmarks]{ntheorem}  \newcounter{dummy}  \numberwithin{dummy}{chapter}    \theoremprework{\setlength \theorempreskipamount{10 pt}\setlength\theorempostskipamount{10 pt}}  \theoremstyle{plain} \theorembodyfont{\upshape} \theoremsymbol{} \theoremseparator{:} \newtheorem{example}[dummy]{Example}    \begin{document}  \begin{equation}\label{eq:example} \int_a^b f(x)\, dx=F(b)-F(a) \end{equation}  By Equation \eqref{eq:example}  \end{document}   New MWE:  \documentclass{book}   \usepackage{amsfonts,amsmath,amssymb,latexsym,verbatim,url,color,mathrsfs,tikz,extarrows,enumerate,lipsum,mathtools}  \usepackage{enumerate,fancyhdr,verbatim,comment}  \usepackage{dsfont}   \usepackage[margin=1 in]{geometry}   \usetikzlibrary{matrix,arrows}  \usepackage[amsmath,thmmarks]{ntheorem}  \usepackage[colorlinks = true,             linkcolor = blue,             urlcolor  = blue,             citecolor = blue,             anchorcolor = blue]{hyperref}  \usepackage[nameinlink]{cleveref}  \newcounter{dummy}      \numberwithin{dummy}{chapter}        \theoremprework{\setlength     \theorempreskipamount{10 pt}\setlength\theorempostskipamount{10 pt}}      \theoremstyle{plain}     \theorembodyfont{\upshape}     \theoremsymbol{}     \theoremseparator{:}     \newtheorem{example}[dummy]{Example}        \begin{document}      \begin{equation}\label{eq:example}     \int_a^b f(x)\, dx=F(b)-F(a)     \end{equation}      By Equation \eqref{eq:example}      \end{document}


execute the "apt install package" command when binary not found

$ xelatex  Command 'xelatex' not found, but can be installed with:  sudo apt install texlive-xetex  If a binary not found but apt knows the package associated with, it would recommend the installation command. When the recommend prompts, is there an easy shortcut or command like maybe instllaptrecommend so that I can skip copy/paste to directly execute the installation command?


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The question is motivated from the following problem:     Let $I\neq A\neq -I$, where $I$ is the identity matrix and $A$ is a real $2\times 2$ matrix. If $A=A^{-1}$, then the trace of $A$ is   $$ (A) 2 \quad(B)1 \quad(C)0 \quad (D)-1 \quad (E)-2$$   Since $A=A^{-1}$, $A^2=I$. If the converse of  is true, then $\lambda^2=1$ and thus $\lambda=\pm1$. And then $\rm{trace}(A)=1+(-1)=0$.   Here are my questions:   Is  $C$ the answer to the quoted problem?  Is the converse of Cayley-Hamilton Theorem, i.e.,"for the square real matrix $A$, if $p(A)=0$, then $p(\lambda)$ is the characteristic polynomial of the matrix $A$" true? If it is not, then what's the right method to solve the problem above?


Can machine learning/AI lower the security existing cryptographic protocols similar to quantum computers?

Initial thinking would be not unless the protocol revealed sensitive local information that could then be analysed by an ML algorithm and applied globally.  local meaning I see messages from Alice and Bob extract some information x, then apply x to all other users.  Not an expert in ML, this was just initial thoughts.


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How Do I See The Most Common Values In A List?

I have a list with a shed load of data points and a lot of them are the same as each other. Is there a convenient command to sort the list to see what occurs the most?  I'm writing the results to a text file, so I can actually see the results of the list?


What if I run a virus/trojan Windows EXE on Ubuntu with Wine?

I've got a file said to contain information I was looking for. Unfortunately it is an executable instead of DOC (as it was meant to be) and the site I've download it from looks suspicious for me. If I was not using Linux, I'd run it on a VM or a separate PC. But running Linux, do I need to worry, or can I just run it with Wine? Can Wine system be infected?


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Find The minimum value of $$2^{\sin^2 \alpha} + 2^{\cos^2 \alpha}.$$   I can easily get the maximum value but minimum value is kinda tricky. Please help.


New top bar is coming to the Stack Exchange network

Update:         See:       I'm the new product manager for the . I’m excited to announce that the top bar design that has been on Stack Overflow for several months is coming soon to the Stack Exchange network.   What took so long?  This was a big change and we really wanted to work out the kinks on Stack Overflow before we pushed to all sites in the network. For example, we recently released some changes to how the review queue menu works in order to address an overall drop in reviews since the new top bar shipped on SO (see  for details). We also adjusted the location of some items, such as the help link, to address feedback.  To meet the needs of the network we needed to adjust some aspects of the design to work with the full range of sites. The design is coherent with the SO design, but isn’t exactly the same. The biggest difference is that site name and Questions/Tags/Users navigation remain below the top bar. This was needed in order to work with sites with long names and/or custom skins.  Most importantly, the site switcher and other key controls will be in the same location across the entire network   New top bar on Stackoverflow.com:   New top bar on webapps.stackexchange.com:   New top bar on gaming.stackexchange.com:    New top bar on a beta site with a long site name:    New top bar for high rep member:    New top bar for moderator:   Why change the top bar?  If this change is new to you, then check out the  blog post and the meta post  for more details.


I am learning the basics of Natural Deduction and I meet a problem about the role of context.   In Natural Deduction, if we have $\vdash A\rightarrow B$, we also have $A\vdash B$; if we have $A\vdash B$, we obtain $\vdash A\rightarrow B$.   My question is: if we have $\Gamma\vdash A$ where $\Gamma$ denotes a context, do we have $\vdash\Gamma\rightarrow A$; and if we have $\vdash\Gamma\rightarrow A$, do we have $\Gamma\vdash A$? I ask this because I didn't see any occurrence of contexts written as $\Gamma,\Delta$ after $\vdash$, is it wrong to write in that way?  Thank you in advance!


this is my first question.I am using below code for remove fragment:      private boolean returnBackStackImmediate(FragmentManager fm) {          List<Fragment> fragments = fm.getFragments();         if (fragments != null && fragments.size() > 0) {             for (Fragment fragment : fragments) {                 if (fragment.getFragmentManager().getBackStackEntryCount() > 0) {                     if (fragment.getFragmentManager().popBackStackImmediate()) {                         return true;                     } else {                         return returnBackStackImmediate(fragment.getChildFragmentManager());                     }                 }             }         }       return false; }   Now,I want after remove fragment, if user click on Back button again, my activity be close.for that I have added these codes into my Activity:      @Override public void onBackPressed() {      if (getSupportFragmentManager().getFragments() == null) {         finish();     } else {          if (!returnBackStackImmediate(getSupportFragmentManager())) {             super.onBackPressed();         }     }  }   but when I press back button and remove fragment and press again I got this error:   java.lang.NullPointerException: Attempt to invoke virtual method 'android.support.v4.app.FragmentManager android.support.v4.app.Fragment.getFragmentManager()' on a null object reference                                                                              at com.safarayaneh.notify.activities.MainActivity.returnBackStackImmediate(MainActivity.java:501)                                                                              at com.safarayaneh.notify.activities.MainActivity.onBackPressed(MainActivity.java:488)                                                                              at android.app.Activity.onKeyUp(Activity.java:2477)                                                                              at android.view.KeyEvent.dispatch(KeyEvent.java:2664)                                                                              at android.app.Activity.dispatchKeyEvent(Activity.java:2730)   I know fragment is null but which condition can I use for this situation?


I'm using less to view a large file and I want to search for a pattern with wildcards — e.g., " x 1??" where ? is any character.  Does less support that, and if so how would I do that interactively?


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A few months ago, I acquired a Windows 7 Ultimate product key and updated from Home Premium to Ultimate. Well, now I get the "This copy of Windows is not genuine" message. I have the Home Premium product key that I was using before I upgraded to Ultimate. I would want to know how I could downgrade from Ultimate to Home Premium without having any CD and only the product key. If it helps, it's a 64-bit OS. Thanks in advance!


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It has been suggested in some quarters that had have, followed by a past participle, is a regionalism that has no place in standard English grammar.  If I had have known you were coming, I would have been prepared, or If I'd have known you were coming, I would have been prepared, mean essentially the same as If I had known you were coming..... But the former is often used for emphasis, and it sounds perfectly idiomatic to me.  So is had have seen etc. grammatically correct?


Application of Lehmann–Scheffé theorem in a sample with normal distribution

Let $Y_{1},Y_{2},\ldots,Y_{n}\sim N(0,\sigma^{2})$. Prove that $T(Y)=\frac{1}{n}\sum_{k=1}^{n}Y_{i}^{2}$ is the MVUE for $\sigma^{2}$.  My approach:  I need to prove that $T(Y)$ is the MVUE for $\sigma^{2}$, so I need to show that:  $T(Y)$ is a sufficient statistic for $\sigma^{2}$. $T(Y)$ is a complete statistic. Therefore, by the Lehmann–Scheffé theorem we can conclude that $T(Y)$ is the MVUE for $\sigma^{2}$.  Since that $$L(\sigma^{2})=\underbrace{\left( \frac{1}{\sqrt{\sigma^{2}} \sqrt{2\pi}}\right)^{n}}_{=h(\mathbf{y})}\underbrace{\exp \left\{-\frac{1}{2\sigma^{2}}\sum_{i=1}^{n}x_{i}^{2} \right\}\cdot \mathbf{1}_{\{x\in \mathbb{R}\}}(x_{i})}_{=g[T(\mathbf{y});\sigma^{2}]}$$ so by the Factorization's theorem we can conclude that $T(Y)$ is a sufficient statistic. Now, for to prove that I need to show that: For all measurable function $g$ and for all $\sigma^{2}$ we have $$\mathbb{E}_{\sigma^{2}}g(T)=0 \implies \mathbb{P}_{\sigma^{2}}[g(T)=0]=1$$ But how can I prove that part? On the other hand, how would you use Rao-Blackwell's theorem to prove this result?


Create local backup of notes in Notes.app on macOS

I'm using a company-issued MacBook where we cannot use iCloud to backup notes. But I would like to have a way to create backups of the notes, since they are not included in the company backup software. Is there a way to do this by hand?   I tried copying the folder:  $HOME/Library/Containers/com.apple.Notes  but when I copied that one to a new Mac, the notes didn't show up when running Notes.app.


Unable to connect to repository in MiKTeX 2.9

In MiKTeX 2.9 Package manager, when I'm trying to synchronize it writes me a message: "The remote package repository is not online...", but I'know server is online (I can use FTP to download packages manualy). When I'm trying to change repository it shows me empty list. Like that:   What can I do to fix this without manual downloading packages from repo?


If "I'm thinking" is correct, why isn't "I'm knowing" correct in formal English?  think+ing = thinking is correct know+ing  = knowing isn't correct   Why?


Take a look on a website with specified viewport size, that is bigger than physical size?

My display driver's maximum screen width is 1280 pixels.   I need to test a website with resolution 1920×1080 pixels. Or 3000×5000.   Different browsers is optional.


I have the following list:  x =['Adam', 'G', '24', '1983', 'Aug', 'August Birthday', 'Steve', 'F', '31', '1970', 'Sep', 'sept bday']   I would like to get the above list into another list but in a way I can work with it like this  x = [('Adam', 'G', '24', '1983', 'Aug', 'August Birthday'),('Steve', 'F', '31', '1970', 'Sep', 'sept bday')]  The Pattern is x = [(0,1,2,3,4,5),(0,1,2,3,4,5)] etc....   What is a good way to do this?  I have tried to iterate over the list using a count and after each line adding 1 to the count so I can get to 6 then start count over again, but I am not sure how to get it into the desired list.


Debian/Ubuntu apt pre-install hook for logging/commit messages?

This is related to .  I've patched /etc/etckeeper/pre-install.d/50uncommitted-changes as follows (to add support for a "PRECOMMIT" file):  #!/bin/sh set -e PRECOMMIT=/root/.etckeeper/pre-install.txt  if etckeeper unclean; then     if [ "$AVOID_COMMIT_BEFORE_INSTALL" = 1 ]; then         echo "" >&2         echo "** etckeeper detected uncommitted changes in /etc prior to $HIGHLEVEL_PACKAGE_MANAGER run" >&2         echo "** Aborting $HIGHLEVEL_PACKAGE_MANAGER run. Manually commit and restart." >&2         echo "" >&2         exit 1     fi     if [ -r "PRECOMMIT" ]; then         MSG=$(cat "$PRECOMMIT")     else         MSG="saving uncommitted changes in /etc prior to $HIGHLEVEL_PACKAGE_MANAGER run"     fi     if ! etckeeper commit "$MSG"; then         echo "warning: etckeeper failed to commit changes in /etc using $VCS" >&2     fi fi [ -r "$PRECOMMIT" ] && mv "$PRECOMMIT"  "$(basename "$PRECOMMIT" txt).$(date +%Y%m%d.%s)"   And I've written a (Bash) shell function for my /root/bashrc which wraps the apt-get command to create the this "precommit" message (and to rename out of the way).  But I'd prefer to patch the hooks in /etc/apt/apt.conf.d/05etckeeper  My question is:  can I capture the apt-get command's arguments from within a DPKG::Pre-Invoke command?


How can I determine local minima from a Kernel Density Estimation?

I have a fairly large 1-dimensional array that I am trying to cluster. I came across several other questions on this site where the top answer is to use a Kernel Density Estimation and then locate local minima:  and .  I have successfully used  to generate KDE's for my data, and they plot beautifully, but how do I calculate the local minima?


TSQL: select the latest N rows, if not specified select all

I want to get the latest N rows of a table. Something like this:  CREATE PROCEDURE [dbo].[spProducts]     @Rows int AS     SELECT TOP(50) *     FROM tblProduct   But if the number of rows is not specified in the input-param @Rows int, all rows should be outputted (select * (all)) Do I need to implement If/Else-statements, or is there maybe a shortcut that can turn the input-param @Rows intinto an asterix?


Money exchange best value for a new middle-aged traveller

I'm travelling to Thailand in September and would like to know if is it better for me to change money here in Australia before I go or when I get to the airport in Bangkok.  If here where would be the best place to get better value?


Functions on $\mathbb{R}^n$ commuting with orthogonal transformations

I am interested in finding the functions $f:\mathbb{R}^n \to \mathbb{R}^n$ for which $f \circ U = U \circ f$ for all orthogonal transformations $U:\mathbb{R}^n \to \mathbb{R}^n$. Note that $f$ need not be linear. Any ideas on the conditions on $f$ ?


Finding positive integers with the same digits

Find the three smallest positive integers $K$ (two digits or greater) with the following properties:      1) $K=\frac{(n)(n+1)}{2}$ for some $n$      2) Each digit of $K$ is the same.   I was able to find the three $K's$ which are $55,66,666$ However, I am looking for a more systematic way. I was able to find the three numbers by testing $n$ I got the following:  For:  $55: n=10 $  $66: n=11 $  $666: n=36$  I am thinking about how can someone solve this problem without a calculator. I believe this problem is written to use a certain idea but I can't seem to find it. Does anyone see it?   As for my research, I've been reading about triangular numbers with the same digits. Someone suggested that I should $(n)$ and $(n+1)$ in prime factorization form.  I noticed that you can't get $6666$  If you try $n=115$, you get $6670$. So $6666$ is not possible.    So basically, I am looking for strategies in how to approach this problem. Any ideas?


How to increase the font size in text-only mode with high DPI

I have installed Ubuntu 15.04 on a Lenovo w550s which has > 200DPI. When I switch into the text-only console (using Ctl-Alt-F1 etc), then the text is so tiny that it can barely be read.   I have tried to fix this using this procedure:      But from the font selection menu, no font that was significantly larger was available (I chose the biggest one from the list) and the text on the console (Ctrl-Alt-F1) is still too tiny to be readable.


Why am I not getting notified by email when my Find My iPhone is used?

I am not getting notified when the Find My iPhone app is used or even if I try searching via iCloud. How can I enable them?


When we start learning about differential equations sometimes we "multiply" both sides of the equation by a differential and then integrate.   Example: $\frac{dy}{dx}=x$ then $dy=x*dx$ and so on.  I have always thought this is a "shortcut" since multiplying by a differential doesn't make a lot of sense to me.  But, why does it work? What are we really doing?  EDIT:  I'll clarify a little more. My specific question is: Why can we treat differentials as real numbers?


I'm toggling the class of an element with this code but I'm pretty sure it can be written more efficiently.  $('.expandable_header').click(function() {     toggle_expandable_icon($(this).find('i')[0]);     $(this).nextUntil('tr.expandable_header').slideToggle(100, function(){     }); });  function toggle_expandable_icon(elem) {     var toOpen = 'fa-plus-circle';     var toClose = 'fa-minus-circle';     if (elem.classList.contains(toOpen)) {         elem.classList.replace(toOpen, toClose);     } else {         elem.classList.replace(toClose, toOpen); }};   Not pointless to say js is not my mother tongue.


Sending compressed folder with shapefiles and QGIS?

When I compress my QGIS file with the folder containing all my shapefiles, how can I maintain the paths?  For example, I made a map on QGIS using a large amount of shapefiles. Once done, I save my QGIS file to  C:\Users\Workcomputer\Desktop\New_folder  From there I compress the shapefiles and the QGIS file located in \New_folder and send the newly made .zip file to myself by email or dropbox.  However, when I download and uncompress the .zip on a different computer, the QGIS file is empty, and I have to re-path all the shapefiles, because they are now located in  C:\Users\Homecomputer\Desktop\New_folder   instead of   C:\Users\Workcomputer\Desktop\New_folder  Is there anyway to short-cut having to do this?


How to disable Xcode's '"ProjectName" is a project downloaded from the Internet. Are you sure you want to open it?' dialog?

This is not a question on how to disable the warning when opening files or apps downloaded from the internet but instead it is about Xcode Projects.  New with Xcode 7.3 released yesterday whenever a project is opened for the first time that was downloaded from the internet a warning pops up asking      “ProjectName” is a project downloaded from the Internet. Are you sure   you want to open it?   How do I disable this warning from popping up?


I want a text book with various examples

Which text is efficient for self-reading number theory introduction? for the third semester of univercity


Why doesn't my post meet quality standards?

I am trying to post this question, but it gets rejected as not meeting quality standards. What can I do to fix it?     I have a django application runnin using django cms. I am trying to   make one specific submenu not clickable.      The menu is like this:  item1|item2|item3             sub_item3             sub_item3       What i want is that everything is clickable except for "item3" menu   item .      How can i achieve this knowing item3 is a django-cms page itself as   are each of its children pages ?


Is there any human female spouse that won't disappear?

So I've tried to get married in skyrim but after the wedding the wife disappears. Is there any female human spouses that WON'T disappear after getting married? If so who?  Also I play on Xbox 360 if that helps. And does getting the legendary edition of the game fix this glitch? I'm sick of using up gold just to see this glitch happen.


Assuming  how economical would it be to load an OS into main memory and run it from there?  I can think I can deal with a few obvious drawbacks (I've survived inside the bounds of a 20gig VM for the last 2 years), but what are the pro's, con's, requirements and cost for running Windows 7 or the latest Fedora or Ubuntu distro strictly from RAM.   Just so there's no confusion, I'm not saying run the OS from a USB stick or live CD.  I'm saying, start the computer, transfer the entire OS into memory from a external HD or 'the cloud' or a big memory stick and run it there. When the machine turns off, save the state to the external storage.


prove that $x^2 + 5 =y^3$ has no solutions for $x,\ y \in \mathbb{Z}$

So the question is completely stated by the title. My own thoughts:  I can prove that $x^2 + 1 = y^3$ has no solutions for $x,y \in \mathbb{Z}$ by using the factorization: $$ y^3 = (x-i)(x+i) $$ in $\mathbb{Z}[i]$, using the fact that $\mathbb{Z}[i]$ is a UFD and that $(x-i)$ and $(x+i)$ are coprime we obtain that they are both cubes and it follows that this is impossible.  Now I would like to apply similar reasoning for this equation, we factor it as follows: $$ y^3 = (x-\sqrt{-5})(x+\sqrt{-5}) $$ in $\mathbb{Z}[\sqrt{-5}]$ but this time $\mathbb{Z}[\sqrt{-5}]$ is not a UFD. However, since $\mathbb{Q}(\sqrt{-5})/\mathbb{Q}$ is a finite seperable field extension we find that the integral closure of $\mathbb{Z}$ in $\mathbb{Q}(\sqrt{-5})$ is a Dedekind domain, this integral closure is exactly our ring $\mathbb{Z}[\sqrt{-5}]$ (which follows from the fact that $-5 = 3 \neq 1 \text{ mod } 4$). In a Dedekind domain we know that we write ideals uniquely as a product of maximal ideals, we can apply this to the ideal $(y)$, $(x-\sqrt{-5})$ and $(x+\sqrt{-5})$ for this to be useful we must first prove that the ideals $(x-\sqrt{-5})$ and $(x+\sqrt{-5})$ are coprime, for this it suffices to show that there is no prime ideal $P \subseteq \mathbb{Z}[\sqrt{-5}]$ that contains $(x-\sqrt{-5})$ and $(x+\sqrt{-5})$.  Let $P$ be a prime ideal s.t. $x-\sqrt{-5},x+\sqrt{-5} \in P$, then it follows that also: $$ 2\sqrt{-5} = x+\sqrt{-5} - (x-\sqrt{-5}) \in P $$ and thus by the given equality: $$ -20 = (2\sqrt{-5})^2 \in P^2 \subseteq (y)^3 $$ so we find an element $a+b \sqrt{-5} \in \mathbb{Z}[\sqrt{-5}]$ s.t. $-20 = (a+b\sqrt{-5}) \cdot y^3$ using the norm: $$ N(r + s \sqrt{-5}) := r^2 +s^2 5 $$ we obtain from this equality thath: $$ 400 = (a^2 + 5b^2) \cdot y^6 $$ but as $400 = 2^4 \cdot 5^2$ we find that $y$ must be equal to $1$ and thus we find that: $$ x^2 + 5 = 1 $$ which is clearly impossible as for $x \in \mathbb{Z}$ we have $x^2 \geq 0$.  From this we can conclude that $(x-\sqrt{-5})$ and $(x+\sqrt{-5})$ are indeed coprime so their decomposition in a product of maximal ideals is disjoint (i.e. we find maximal ideals $\mathfrak{p}_1,\dots,\mathfrak{p}_r$, $\mathfrak{q}_1,\dots,\mathfrak{q}_s$ and natural numbers $e_1,\dots,e_r,f_1,\dots,f_s$ s.t.:  $$(x-\sqrt{-5}) = \mathfrak{p}_1^{e_1}\dots\mathfrak{p}_r^{e_r}, \qquad (x+\sqrt{-5}) = \mathfrak{q}_1^{f_1}\dots\mathfrak{q}_r^{f_r}$$ where all $\mathfrak{p}_i$ and $\mathfrak{q}_j$ are different. For $(y)$ we also find such a decomposition, which implies that the decompositions of $(x-\sqrt{-5})$ and $(x+\sqrt{-5})$ must be of the form: $$ (x-\sqrt{-5}) = \mathfrak{p}_1^{3e_1}\dots\mathfrak{p}_r^{3e_r}, \qquad (x+\sqrt{-5}) = \mathfrak{q}_1^{3f_1}\dots\mathfrak{q}_r^{3f_r} $$ which implies that there is some ideal $I$ in $\mathbb{Z}[\sqrt{-5}]$ s.t. $(x+\sqrt{-5}) = I^3$ so we find elements of $I$: $a_i+ b_i \sqrt{-5} \in I$ for which: $$ x+\sqrt{-5} = \prod_{i=1}^3(a_i+ b_i \sqrt{-5}) $$ and then I would like that this is impossible, but at this point I'm stuck.  I'm sorry if my own idea is absolutaly worthless but this is the first time I try to solve this kind of exercise.


What is $\mathbb{E}[W(s)\mathrm{e}^{W(S)}]$ where W(S) is a standard Brownian Motion?

I know that since it is a Brownian motion that $W(s)\sim{N(0,s)}$. One approach I tried, was to see that $W(s)-W(0)\sim N(0,1)$ and to let $X = W(s)$ and then solve $\mathbb{E}[X\mathrm{e}^X]$ but I end up with some awful integral. I was wondering whether there was an easier way? Or perhaps a simple way to solve this integral: $\int_{-\infty}^{\infty} \frac{1}{\sqrt{2{\pi}s}}x\mathbb{e}^{x}\mathbb{e}^{-\frac{x^2}{2s}}$


Is "one" unnecessary in this quote of Melville?

I cannot make much sense of one in the following passage from :  Now the various species of whales need some sort of popular comprehensive classification, if only an easy outline one for the present, hereafter to be filled in all its departments by subsequent laborers.  If  is a noun in this passage, then  must serve here as a pronoun. If so, isn't the sentence lacking in punctuation? Rewriting would make it less ambiguous:  Now the various species of whales need some sort of popular comprehensive classification, if only an easy outline, one for the present hereafter to be filled in all its departments by subsequent laborers.  Furthermore, I can't help thinking that one is not needed here at all:  Now, the various species of whales need some sort of popular comprehensive classification, if only an easy outline for the present, hereafter to be filled in all its departments by subsequent laborers.  If Melville correctly worded this sentence, what is the function of one in it? What are your thoughts on my modifications?


How many combinations are possible in the game tic-tac-toe (Noughts and crosses)?  So for example a game which looked like: (with positions 1-9)  A1   --   B1  A2   --   B2  A3   --   --   [1][3][4][6][7] would be one combination


Smolin on Cosmological selection and neutron stars

Regarding the cosmological selection hypothesis and testable predictions, Lee Smolin asserted the following:     "Smolin: I did make two predictions which were eminently checkable by   astrophysical and cosmological observations, and both of them could   easily have been falsified by observations over the last 20 years, and   both have been confirmed by observations so far.      One of them concerns the masses of neutron stars and the prediction is   there can't be a neutron star heavier than about twice the mass of the   sun. This continues to be confirmed by the best measurements of the   masses of neutron stars."   What is he referring to? As far as I know, the neutron star mass limit is a prediction of GR, and doesn't suggest that any fine-tuning is involved in it. Is this correct?


How to see the password what we are entering in RHEL6. If not how to see at least the entering password in some special characters.


Getting Error 324 (net::ERR_EMPTY_RESPONSE) when saving changes to content/views/modules

For a few weeks now, I've been getting an error when saving certain changes. This error, in Chrome, is      Error 324 (net::ERR_EMPTY_RESPONSE): The server closed the connection without sending any data.   After I click the save button, the page seems to load for a while (10 seconds or more), then directs to that Chrome error page. But, if I reload the page manually, the changes I've added have actually been saved. I've noticed this happening when: adding a new content type, adding a new field, saving changes to a view, disabling or enabling a module, and even clearing the cache.  After some digging, I found out that this error gets posted to Apache's error log every time this happens:     [Fri Mar 30 09:27:11 2012] [error] [client 74.142.25.146] PHP Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 12893929 bytes) in /var/www/drupal/includes/database.mysqli.inc on line 329, referer:    [Fri Mar 30 09:27:12 2012] [notice] child pid 17934 exit signal Segmentation fault (11)   I have two sites I work on, one of which is simply a week-old backup version of the other. Interestingly, the error printed to the log for the up-to-date site is slightly different: The file that seems to be generating the error is includes/database.inc, line 225 instead of includes/database.mysqli.inc. In both cases, the line mentioned is simply an escape string function. mysqli_real_escape_string() and db_escape_string() specifically.  I'm at a loss. The fact that it's a Drupal core file generating the error is bothersome. Does anyone have any idea why this is happening?


What does the equal sign mean in mathematics?

When we say $a=a$ means that are absolutely the same right? What does equal mean in $3+2=7-2$? Does it mean that they are absolutely the same or that the value is just the same?


Let $q$ be a prime integer. Show that for each $x∈GF(q)$ there exist elements $r$ and $s$ in $GF(q)$ satisfying $x=r^2+s^2$.  I'm stuck on this problem. Any solutions or hints are greatly appreciated.


"Everyone want their homes to be at the centres of cities" Is this correct usage or is there any alternative way to convey the same?


I'm trying to create a plot similar to this, where histogram bins are plotted along each axis of some randomly distributed data from a csv-file:     Ideally, the histogram bars would be mirrored along the their main axis, so that unlike in this example, the histogram orgin is on the axis. How can this or something similar be done in pgfplots?


Questionable Proof in Visual Complex Analysis

I am currently reading the book "Visual Complex Analysis". It's a great book so far, but already in the beginning the proof of the identity theorem seems dubious. I mean, it's known from high-school algebra, that you're not allowed to divide by z if you set z = 0.  Isn't this proof completely wrong? Some friends I've asked even told me that this theorem is wrong in the reals, so wouldn't a correct proof have to use properties of the complex numbers? Is it even possible to prove this with elementary methods? I've seen proofs that use properties of holomorphic functions but haven't gotten that far in my book yet, so I have no experience with holomorphic functions.


Let: $$f(x) = \begin{cases} 5-x,  & \text{if $x$ is irrational.} \\[2ex] 1+x, & \text{if $x$ is rational.} \end{cases}$$   Prove that $\lim_\limits{x\to 2}f(x)=3.$ Prove that $\lim_\limits{x\to 0}f(x) $ doesn't exist.   Solution Attempt: I want to use the definition of continuity. by saying that for each each $\epsilon>0$ there is a $\delta>0$ s.t. $|x-2|<\delta$  $\Rightarrow$ $|f(x)-f(2)|<\epsilon$. and somehow I thought about using the qualities of $|f(x)|$ and try to get that an equation that might help me in the proof. but got stuck there. any help?


The ridge regression estimate is given by $$\beta^{*}=(X'X+kI)^{-1}X'y, k≥0,$$ where $X$ is the feature matrix. The original paper, , states that the eigenvalues, $\lambda_i$, of $X'X$ are related to eigenvalues, $\xi_i$, of $W = (X'X+kI)^{-1}$ as $\xi_i=1/(k+\lambda_i)$. This expression follows from solving the characteristic equation $|W - \xi_iI|=0$. I can only imagine using cofactor representation of the determinant. However, the inverse in $W$ complicates matters. How exactly does one solve this characteristic equation?


I need to find two infinite fields of characteristic $p$ which are not isomorphic.


I wanted to find my progress to the  badge from my profile, but it's not listed under the available badges. I ran  to get my progress, but I'm curious why isn't it showing up otherwise on any of the sites.


I would like the user to have full rights on this folder (as well as all sub-directories and files in it):  ~/.blabla   currently owned by root.  I have found numerous posts (in this forum and elsewhere) on how to do this for files but I can't find a way to do it for whole folders.


Eigenvalue Problem -- prove eigenvalue for $A^2 + I$

This is a proof I've been trying to figure out since the problem was presented to me.  We are given that $\lambda$ is an eigenvalue for a matrix $A$ and the vector $u$ is the eigenvector corresponding to $\lambda$.  The problem asks to us to prove that $\lambda^2 + 1$ is an eigenvalue for $A^2 + I$, where $I$ is the identity matrix.  I am not quite sure where to start.  My first instinct was to somehow manipulate $Au = \lambda u$, but I'm not quite sure what to do with it.  Any ideas for this one? It's certainly an interesting problem, in my opinion.


Does Circle of the Forged increase the Wildshape AC by 2 or 3?

The druid's Wild Shape feature in D&D 5e says:  You retain the benefit of any features from your class, race, or other source and can use them if the new form is physically capable of doing so. However, you can't use any of your special senses, such as darkvision, unless your new form also has that sense.  From the warforged's Integrated Protection racial trait:  You gain a +1 bonus to Armor Class  From 's Circle of the Forged Skin of Steel feature:  Starting at 2nd level, while you are transformed by Wild Shape, you gain the following benefits: You gain a +2 bonus to Armor Class...  Warforged druids  because the shape they transform into isn't built like a warforged, but Circle of the Forged clearly lets them keep their wood and metal composition:  While in beast form, your body is made from the same materials as a warforged; your muscles are rootlike tendrils protected by armored plates. It’s obvious to an observer that you are not a normal animal.  So does that mean if you're a Circle of the Forged warforged druid, you get a +3 AC bonus to whatever beast's natural armor you turn into? E.g. Giant spider = 14 + 1 + 2 = 17? This seems like a big difference from normal druids, even moon druids, so I wanted to double check.


I had originally coded the program wrongly. Instead of returning the Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 should = only those numbers between 1 & 20), I have written for the program to display all Fibonacci numbers between a range (ie. startNumber 1, endNumber 20 displays = First 20 Fibonacci numbers). I thought I had a sure-fire code. I also do not see why this is happening.  startNumber = int(raw_input("Enter the start number here ")) endNumber = int(raw_input("Enter the end number here "))  def fib(n):     if n < 2:         return n     return fib(n-2) + fib(n-1)  print map(fib, range(startNumber, endNumber))   Someone pointed out in my Part II (which was closed for being a duplicate - ) that I need to pass the startNumber and endNumber through a generator using a while loop. Can someone please point me in the direction on how to do this? Any help is welcome.    I'm a learning programmer and I've run into a bit of a jumble. I am asked to write a program that will compute and display Fibonacci's Sequence by a user inputted start number and end number (ie. startNumber = 20 endNumber = 100 and it will display only the numbers between that range). The trick is to use it inclusively (which I do not know how to do in Python? - I'm assuming this means to use an inclusive range?).  What I have so far is no actual coding but rather:   Write Fib sequence formula to infinite Display startNumber to endNumber only from Fib sequence.   I have no idea where to start and I am asking for ideas or insight into how to write this. I also have tried to write the Fib sequence forumla but I get lost on that as well.


Is there an easy proof for ${\aleph_\omega} ^ {\aleph_1} = {2}^{\aleph_1}\cdot{\aleph_\omega}^{\aleph_0}$?

The question contains 2 stages:    Prove that ${\aleph_n} ^ {\aleph_1} = {2}^{\aleph_1}\cdot\aleph_n$    This one is pretty clear by induction and by applying Hausdorff's formula.    Prove  ${\aleph_\omega} ^ {\aleph_1} = {2}^{\aleph_1}\cdot{\aleph_\omega}^{\aleph_0}$   Is there an easy proof for the second one?  Thanks in advance.


Using a familiar to deliver a touch attack with the Ready action

The last paragraph of the Find Familiar spell contains the following:     ...when you cast a spell with a range of touch, your familiar can   deliver the spell as if it had cast the spell. Your familiar must be   within 100 feet of you, and it must use its reaction to deliver the   spell when you cast it.   Since the attack functions as a reaction for the familiar, it must already be within touch range of the target to deliver the spell, correct?  If a target is 30ft away, could a wizard ready a Shocking Grasp spell for "when my familiar is within touch range of that bugbear", allowing his owl to fly over, deliver the spell attack, and then fly away on its turn?   I assume his owl could not ready an action to fly to a goblin and back triggered upon "the wizard casts shocking grasp" since both would require a reaction, correct?


Anyone who can solve it or give me an idea on how to try to do it myself?  $$1 + \frac{1}{\sqrt{2}} + \frac{1}{\sqrt{3}} + ... + \frac{1}{\sqrt{n}}\geq \sqrt{n}, \;\;\;n \in \mathbb{N^*}$$


When we push a box, the box applies an opposite force on my hand, but why does my hand move with the box as I push the box if the net force of is 0?

When we push a box, the box applies an opposite force on my hand, but why does my hand move with the box as I push the box if the net force of my hand is 0? What is happening?


Posthumous authorship or acknowledgement

Suppose I am working on a book that is a broad expansion of a survey article I wrote with a collaborator, Dr. Y, who passed away recently. I sent Y extremely early drafts of some chapters and invited Y to be a coauthor. Y gave a lot suggestions in the structure, content, and style of the book, yet Y remained vague about coauthorship (probably because he had doubts if he will live long enough). Y never said yes or no. Y never participated in the actual writing. But Y's suggestions became the high level blueprint that guided the development of the book. This draft is only about 60% done, but I'm wondering: in this case, should Y be a coauthor?


How can I mix two materials based on incoming light

I was watching the  tutorial by Andrew Price and I was able to follow along in Cycles until I hit the part where he mixes the day and night materials together so that the lights show up on the "dark side" of the earth.  How can I recreate this effect in cycles? I thought I could use the ray information to tell me if there was incoming light but I've found no such node to give me this information.


A new notation for operations and some questions

let $x^{/1/}=x+x$ (addition)   $x^{/2/}=x.x$ (multiplication)  $x^{/3/}=x^x$ (exponentiation)  $x^{/4/}={}^xx$ (tetration)  and so on.....  I have the following questions:     $(1)$ Can we define an operation between two known operations (Ex.addition and multiplication), where $n$ in $x^{/n/}$ is fractional (Ex. $x^{/1.5/}$)?      $(2)$ Is there a closed form for $x^{/x/}$?      $(3)$ Is infinitation ($x^{/\infty/}$) equal to infinite tetration $\left( x^{x^{x...}}\right)$?   I think the answer to the last question is true as infinite tetration is equal to infinite pentation (as both of them equal to $x^{x^{x^{.^{.^.}}}}$ when we convert them to their exponentiation form.) Following the same logic, any $n$-ation is equal to $x^{x^{x^{.^{.^.}}}}$, and therefore infiniation is also equal to infinite tetration.     Edit: Does this notation seem useful for defining operations?


I use the code  \begin{figure}[ht] \begin{center} \subfig{\label{dfg}\includegraphics[width=1\textwidth]{figures/2dcontour}} [Figure (A)]  \subfig{\label{dfg}\includegraphics[width=\textwidth]{figures/3dcontour}} [Figure (A)]  \end{center} \caption{} \label{fig:subfigureExample} \end{figure}   But it never gives me side by side figures, only in case I make the figures very small let's say scale=0.1, they become beside each other.  I have looked many online webs about this but they don't do anything different, and I do not know why it does not work for me.  Worth mentioning that subfigure did not work for me and that is why I have used subfig.


I'm struggling with this question and was wondering if anyone could help. Thanks! When a polynomial $P(x)$ is divided by $(x-2)(x+4)$, the remainder is $(3x-5)$. What is the remainder when $P(x)$ is divided by $(x-2)$? Any help would be greatly appreciated! Edit: This is my attempt so far: I have expanded $(x-2)(x+4)$ which gives me $x^2+2x-8$ but  for remainder theorem it is $f(x-a)$ remainder so it's a bit different, hence I don't know how to proceed. I also thought of doing $P(x) =  (x^2+2x-8)Q(x) + 3x-5$ but don't know where to go from here.


In an infinite linearly ordered set every initial section is finite. ¿Is it isomorphic to $\langle\mathbb{N}\,,\,\text{<}_{\mathbb{N}}\rangle$?

As the title of the question suggests, if $\langle A\,,\,<\rangle$ is an infinite linearly ordered set such that for each $a\in A$, the initial section $\text{sec}(a,A,<)$ is a finite set, ¿is it true that it must be isomorphic to  $\langle\mathbb{N}\,,\,\text{<}_{\mathbb{N}}\rangle$?  Obviously, every well-ordered set that verifies this property is isomorphic to $\langle\mathbb{N}\,,\,\text{<}_{\mathbb{N}}\rangle$, for if $\langle A\,,\,<\rangle$ is a well-ordered set, there exists a unique ordinal $\alpha$ such that $\langle A\,,\,<\rangle$ is isomorphic to $\langle\alpha\,,\,\in_{\alpha}\rangle$. In that case, every initial section of the first turns into an ordinal less than $\alpha$, and if every initial section of the first is finite, then every ordinal less than (or in other words, contained in) $\alpha$ is finite, so $\alpha$ is equal to $\omega$, the set of all natural numbers.  However, since a set that is not well-ordered cannot be isomorphic to one that is well-ordered, like $\langle\mathbb{N}\,,\,\text{<}_{\mathbb{N}}\rangle$, we must prove that if every initial section of $\langle A\,,\,<\rangle$ is finite, then the set is well ordered. How shall we proceed?  Thanks in advance.


What is an ideal setup for detecting objects moving through an enclosed space?

I'm trying to create an ammo counter for an airsoft gun. I'm going to control it with an attiny series MCU and i want to detect the projectiles exiting the barrel using a light based sensor. Now that's the question:  Which method of detection is the best for such application? A photodiode, a phototransistor or other, perhaps laser based sensors?  The projectile is 6mm in diameter and at 115 m/s after exiting the barrel which means that the sensor will have around 70μs to detect it.


In Hatcher's Algebraic Topology, section $3.3$, he defines:     A local orientation of a manifold $M$ at a point $x$ is a choice of generator $\mu_x$ of the infinite cyclic group $H_n(M,M\setminus\{x\})$.   My question is why is $H_n(M, M\setminus\{x\})$ necessarily cyclic?  I can see this for $M=\mathbb{R}^n$, because by the relative homology sequence we get: $$H_n(\mathbb{R}^n,\mathbb{R}^n\setminus\{x\})\simeq H_{n-1}(\mathbb{R}^n\setminus\{x\})\simeq H_{n-1}(\mathbb{S}^{n-1})\simeq \mathbb{Z}$$ This case is easy because $\{x\}$ and $\mathbb{R}^n$ have trivial homology for $n>0$.  How am I supposed to see this in the general case?


I have two Schengen visas with adjoining dates, is it OK to travel?

I have two Schengen visas, both multiple-entry, both issues by the Netherlands embassy. One expires on the 30th of September and the other start October 1st. I want to be in Paris from 30th Oct-2Oct. Is it OK to travel?


Is there a way to read the rotation_quaternion data of an object that is under the control of the physics engine?

I'm trying to use blender to test the probabilities associated with different faces of non-cubic dice (some of you may even know why). I've already written a python script that randomly sets the objects position, rotation, initial linear velocity and initial angular velocity, then bakes the physics and jumps to a frame where the shape is likely in a settled position. The problem is that the rotation data at this frame seems to be the same as the frame right before the physics engine took over. It looks like the physics engine doesn't operate directly on object transformations. Is there a way to get this rotation information from python? Right now I can't even seem to find it in the UI.


I'm relatively new to LaTex and I want to use a BibTex file. I read online to build in the following sequence: latex, bibtex, latex, latex. I tried this, but it is still not working.  When running the BibTex file, the console gives me the following error:  I couldn't open file name `bib.aux'   I am using TexShop on Mac. In my files I have the following:  Tex file:  \bibliography{bib} \bibliographystyle{ieeetr}   Bib file:  @BOOK{DUMMY:1,       AUTHOR="John Doe",       TITLE="The Book Without Title",       PUBLISHER="Dummy Publisher",       YEAR="2014", }


Difference between BeanFactory and ApplicationContext?

Both are actually ioc containers. But what is the actual difference between them? Which one is better to use?


Finding all integer solutions of $5^x+7^y=2^z$

Find all integers $x,y,z$ such that $5^x+7^y=2^z$.   This one comes from an online contest that I arranged some years ago, and I can assure that a completely elementary solution exists.


The product of a sum of squares is a sum of squares

If $x=a^2+b^2$ and $y=c^2+d^2$   how can i prove that xy is also the sum of two rational squares?   My teacher told me there are various methods to attack this problem but an easy way is to use the norms of guassian integers but I can't see how it would help.


How do I get excel to not mess around with the formatting of a .csv file

I have two issues with a csv file that occur when I try and edit it in Excel.   I have an ISBN column that gets reformatted to scientific format every time I save the file The encoding for the file is changed from UTF-8 to ANSI when I open the file.   It is really, really frustrating and a complete waste of time.  Is there any way that I can force Excel to leave the format of the file alone?


Remove items from navigation bar of File Explorer

I try to use Windows 10 via Parallels Desktop in my new Mac.   In the File Explorer of Windows 10, I see the following sidebar. Does anyone know how to remove 3D Objects and Movies from there?


This is the terminal message I keep getting when trying to update via: sudo apt-get update  $ sudo apt-get update [sudo] password for petros: Reading package lists... Done E: Could not get lock /var/lib/apt/lists/lock - open (11: Resource temporarily unavailable) E: Unable to lock directory /var/lib/apt/lists/   How can I solve it?


How much older is Hermione Granger than she should be?

During J. K. Rowling's third Harry Potter book, The Prizoner of Azkaban, Hermione Granger makes extensive use  of a Time Turner to be able to attend all of her classes. For this she travels back in time to attend two parallel classes at the same time from everybody else's viewpoint. However from her viewpoint, they happen sequentially.  As a result of this, she should have aged two hours compared to everybody else who just aged one hour (or however long a class actually lasts at Hogwarts).  Do we know or can we estimate how much longer she lived during that school year compared to how much she would have aged normally? Would the added lessons have accumulated to a significant amount?


Why do particular materials allow particular light waves to pass through them?

To be honest, I really don't understand this at all.  If we take cardboard for example, obviously gamma rays can penetrate cardboard because the light has such a high energy, and obviously radio waves can penetrate cardboard because a cell phone will work even when entirely enclosed in cardboard.  So high and low energy photons will pass through cardboard, but I cannot see through it, so it seems that all (or nearly all) visible light will be absorbed in the cardboard. I suppose that my hypothesis for this would be that the sun emits a large amount of light in the visible spectrum, so our eyes have evolved to detect it, and plants have evolved to absorb this same spectrum of light for photosynthesis (both plants and humans thus evolving to best utilize the EM radiation given off by the sun).  Since cardboard is made from plant material, it is thus specifically good at absorbing visible light, while allowing other wavelengths to pass through.  I have no idea if that is true, but even if it is, it only answers my question for plant-based material... I still have no idea why glass can hold in heat, yet visible light and radio waves may still pass through.


Ubuntu 17.04 taking too much time to boot

My laptop has a core i3 processor, 4 GB RAM and a 1 TB SATA HDD. It takes too much time to boot.       31.658s nmbd.service      22.035s plymouth-quit-wait.service      14.369s preload.service      14.245s click-system-hooks.service      12.016s ModemManager.service      11.097s dev-sda1.device      10.114s NetworkManager-wait-online.service       6.552s irqbalance.service       5.533s networking.service       5.329s accounts-daemon.service       5.204s NetworkManager.service       5.179s sddm.service       5.173s speech-dispatcher.service       5.171s loadcpufreq.service       4.710s winbind.service       4.657s lm-sensors.service       4.626s appgrid.service       4.626s gpu-manager.service       4.248s avahi-daemon.service       4.243s thermald.service       3.858s fwupd.service       3.802s apparmor.service       3.648s dnsmasq.service       3.562s upower.service       2.473s polkit.service       2.432s plymouth-read-write.service       2.320s smbd.service       2.302s grub-common.service       2.095s gdm.service       1.986s keyboard-setup.service       1.846s systemd-backlight@backlight:intel_backlight.service       1.811s rsyslog.service       1.521s systemd-fsck@dev-disk-by\x2duuid-BFC4\x2d9612.service       1.521s systemd-tmpfiles-setup-dev.service       1.263s systemd-modules-load.service       1.242s systemd-resolved.service       1.188s systemd-rfkill.service       1.114s systemd-udevd.service        997ms apport.service        934ms dns-clean.service        863ms sys-kernel-debug.mount        862ms dev-hugepages.mount        860ms dev-mqueue.mount        842ms systemd-tmpfiles-setup.service        787ms user@126.service        760ms systemd-timesyncd.service        758ms openvpn.service        707ms user@1000.service        697ms systemd-user-sessions.service        539ms dev-sda3.swap        491ms hostapd.service        455ms systemd-udev-trigger.service        415ms ufw.service        413ms hddtemp.service        411ms systemd-sysctl.service        407ms rc-local.service        392ms alsa-restore.service        388ms udisks2.service        378ms console-setup.service        371ms switcheroo-control.service        371ms pppd-dns.service        365ms systemd-journald.service        363ms colord.service        336ms snap-core-1689.mount        268ms systemd-update-utmp.service        242ms plymouth-start.service        242ms systemd-random-seed.service        235ms packagekit.service        228ms systemd-backlight@leds:dell::kbd_backlight.service        208ms dev-loop0.device        192ms snap-pin\x2dtown-2.mount        180ms boot-efi.mount        180ms kmod-static-nodes.service        167ms systemd-journal-flush.service        119ms dev-loop1.device        106ms setvtrgb.service         96ms wpa_supplicant.service         44ms resolvconf.service         38ms geoclue.service         37ms rtkit-daemon.service         32ms systemd-remount-fs.service         20ms snapd.socket         18ms snapd.autoimport.service         12ms cpufrequtils.service          8ms ureadahead-stop.service          7ms systemd-update-utmp-runlevel.service          3ms lightdm.service          2ms sys-fs-fuse-connections.mount   How can I improve this?


How do character device or character special files work?

I am trying to understand character special files. From , I understand that these files  "provide an interface" for devices that transmit data one character at a time. My understanding is that the system somehow calls the character device instead of calling the device driver directly. But how does the file provide this interface? Is it an executable that translates the system call? Can someone explain what's up.


Let $f$ has following properties:   1)f has continuous derivative in$[0,1]$; 2)$f(0)=0$; then proof $$\int_{0}^{1}|f(x)|^2\,dx\le\int_{0}^{1}|f{'}(x)|^2\,dx$$   I think the condition "$f(0)=0$"may be used to add $f(0)$ or $f^2(0)$ in any place. And then maybe I can use the Lagrange Mean Value Theorem to substitude $f(x)-f(0) $with the $f{'}(\theta)x$. But I can't proof it. So How can I do with this problem? thank you.  By the way, a question that has been asked is quite similar to it:


I read a lot of pdfs using Mendely and I want to buy an Ubuntu tablet for reading these pdfs on the go. I want to sync my pdf directory on my desktop (that's also running Ubuntu) with my tablet using rsync.  Question 1) When is a tablet with Ubuntu Touch installed going to be on the market?  Question 2) Shall I just buy a normal tablet and install Ubuntu on it? Can this be done easily with, say, a Samsung Galaxy Note?  Question 3) If I can install an application in Ubuntu, will I definitely be able to install it in Ubuntu touch? Will Ubuntu touch be incompatible with any Ubuntu apps?  I don't want to have to 'jailbreak' anything or do anything flakey. I just love Ubuntu, and I want it on the go. What is the best way to achieve this?


Horizontal space between chapter number and title in book

I am writing a document with the bookclass and a redefined \thechaptercommand. Since I have a lot of chapters, the chapter number and the chapter title overlap in the TOC. How can I change the horizontal space between them? I have only seen solutions that do not work for the bookclass.   MWE:  \documentclass{book} \begin{document} \tableofcontents \renewcommand*{\thechapter}{I.\arabic{chapter}} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \chapter{AAA} \end{document}


I'm on a rather low-end machine (Intel Atom Cherrytrail) and the visual effects of Ubuntu 17.10 are not processed very well. It's so slow that it's often a bit confusing. Is there a way to disable transitions like the apps sliding in from the left bottom corner?


Contradiction in information resources on capturing UV light with a digital sensor

I encounter a contradiction.   Many resources state that a digital sensor are unsensitive to UV light. Even wikipedia, "However, newer photographic film and digital cameras are highly insensitive to UV wavelengths." .  Digital Photography Review goes even to the point that a digital photographer won't even need it on a beach (an UV-light rich area). "digital sensors are not and hence do not need UV filters in even bright sunlight".   While other resources state that digital sensor are sensitive to UV light.    Can someone clarify this contradiction?  My prognosis is that a digital sensor is sensitive to UV light, but sensor manufactures include an UV blocking system on the sensor. But I don't know if that's true. I do know that IR light is blocked through a IR-absorption glass on the sensor itself.   Is my prognosis correct?


Choosing a blender that can puree hard fruit (like coconut)

I'm thinking about buying a blender since my food processor doesn't do a great job at pureeing tomatoes or blending my homemade almond milk. I'm considering buying a blender that can also puree fresh coconut if I can find one withing my budget. I'd like to spend 70€ tops. In my country (Portugal) I can find blenders with 1000W and 1200W within this price range. These are supposed to be high speed blenders, but for the blenders I'm seeing I can't find any reviews saying they can puree coconut. Will any blender over 1000w puree coconut? How can I know? Any advice?


Why do the following Network Transformations give different answers?

I did a Star to Delta Network Transformation and a Delta to Star Network Transformation on different parts of the original circuit as shown in the image below.  It gave me two new circuits. On solving those circuits, I get different answers for the equivalent resistance. Why is this so?


due to the huge amount of data in my plot I wasn't able to compile the whole badboy at once after creating a tikz file and then using latex. Since the save_size won't go higher than 80000.  so while searching the internet I stumbled across another solution. I created a coordinate system and a colorbar as tikz without any plot via matlab. Afterwards I created the plot without any axis or so as a png picture.  The next would be to include the png graphic in my tikz file. So I did that but when I compile the whole tex file in which I \input my tikz file, the tikz picture and the plot picture won't align as I wish. I mean of course I can get my result after scaling and moving my included graphic but it is too time consuming.  \begin{axis}[% width=4.1in, height=3.80333333333333in, view={0}{90}, %scale only axis, xmin=0, xmax=16, xtick={ 4,  8, 12}, xlabel={x/H}, ymin=-5, ymax=5, ytick={-3,  0,  3}, ylabel={y/H}, zmin=-1, zmax=1, title={T}, colormap={mymap}{[1pt] rgb(0pt)=(1,1,1); rgb(64pt)=(1,1,0); rgb(160pt)=(1,0,0); rgb(255pt)=(0.0104167,0,0)}, colorbar, point meta min=717.475533976793, point meta max=2320.87848806079, anchor=south west ]  \node (myfirstpic) at (0,0) [anchor=south west]{\includegraphics[width=4.1in,height=3.80333333333333in]{testplot_zsmngesetzt.png}};    \end{axis}   Especially what i dont get is why, even though my created axis and my included graphic are anchored south west, my graphic wont start at the same point as my axis  Do you have any idea how I can automatically align the two and let them start at the same point?   sincerely Mille


For a long time I used to losslessly convert muliple PNGs to a single PDF using the following template:  \documentclass[a4paper]{article} \usepackage{pdfpages} \usepackage[margin=0pt]{geometry} \begin{document} \pagestyle{empty} \enlargethispage*{0cm} % % \centering{ \includegraphics[width=.99\paperwidth,totalheight=.99\paperheight,keepaspectratio]{img1.png} \clearpage \includegraphics[width=.99\paperwidth,totalheight=.99\paperheight,keepaspectratio]{img2.png} \clearpage } \end{document}   Lately, I've been getting (on Ubuntu 12.04)  ! Missing $ inserted. <inserted text>                  $ l.10 ...ht,keepaspectratio]{img1.png}   What's wrong, what's changed? Alternatives?  Update: turns out this only happens with filenames with spaces (so "img 1.pdf", not img1.pdf). How can this be avoided?


statistical modelling for imbalanced data

I am dealing with a binary response (good/ bad) type data set of size 2153, which reflects a dependent variable. Out of these, only 67 are in favor of "bad" and the remaining are of "good". Also, i have 3 independent variables.  How can i model my data set statistically? I tried the logistic regression, but the results are not satisfactory. Does SPSS have any solution for handling such types of imbalanced data?


some \newcommand instructions not working

I have  created some new short command using \newcommand in the following example:  \documentclass[12pt,twoside,a4paper]{book}       \usepackage{enumerate,amsmath}    \newcommand{\ba}{\begin{array}}      \newcommand{\ea}{\end{array}}    \newcommand{\ben}{\begin{enumerate}}       \newcommand{\een}{\end{enumerate}}    \newcommand{\bal}{\begin{align}}       \newcommand{\eal}{\end{align}}    \newcommand{\bc}{\begin{center}}      \newcommand{\ec}{\end{center}}    \newcommand{\de}{^\circ}    \begin{document}       \bc       $5\de$       \ec    \ben       \item Text   \item Text   \een     $\ba{cc}     a & b\\    c & d     \ea$     \bal       & r\\       & f       \eal     But     \begin{align}      & r\\       & f      \end{align}    is working.      \end{document}   All \newcommands are working well except  \bal and \eal. I don't know why it is not working.


Recently the Duchess of Cambridge gave birth to a healthy baby boy. The announcement from Buckingham Palace said "The Duchess of Cambridge has been delivered of a son."  This struck me as a very odd grammatical structure that I don't quite understand. Of course I understand what is meant: "She gave birth to a male child" and I presume it is put this way for the purposes of delicacy. But I was wondering if someone could explain how this grammatical structure works.


why there is no clone operation for collections in Java ? There must be able to copy the contents of the collections to a new collection and modify the second collection without affecting the first one


E: Type 'sudo' is not known on line 1 in source list /etc/apt/sources.list.d/mono-xamarin.list

I don't know what caused the following to happen:    The content of /etc/apt/sources-list.d/mono-xamarin.list is sudo apt-get update.


How can I align button vertically in nav bar?

I'm practicing creating a website, and am currently trying to replicate . At the moment I am working on the navigation bar, but I am unable to vertically align the button vertically in the nav.    .header {   background-color: red;   padding: 40px 20px; }  .header h1 {   background-color: yellow;   float: left; }  .header h1 img {   display: block; }  .header__nav {   background-color: aqua;   float: right; }  .header__nav li {   float: left;   height: 38px; }  .header__nav li a {   padding: 0 20px;   display: inline-block;   line-height: 38px; }  .contents {   background-color: green; }  .footer {   background-color: blue; }

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<button class="menu">menu</button>

   contents
    footer        I wanna align the top-right button of the nav bar vertically. I know this can be solved using display: flex;, but I wanna solve it another way. Is there a proper way to solve this issue?


Does every inner product fail to turn $C[0,1]$ into a Hilbert space?

I have the following question:     With the usual inner products that come in mind, $C[0,1]$ is not a Hilbert space. But is it true that every inner product fails to turn $C[0,1]$ into a Hilbert space? If so, then I   would be curious, how to prove this.   Thank you very much for the help!  Yes, I would be interested in the case that the inner product on $C[0,1]$ gives an equivalent topology as the sup norm on $C[0,1]$, but I forgot to clarify this, when typing the question.


Sequence of tenses for facts irrelevant of the moment of speech

Let's consider two sentences:     (1) I suggested that the word zeitgeist was of German origin.   (2) The lecturer said the Pluto's orbital period is more than 200 years.   In both cases, the facts are always valid and  irrelevant of the moment of speech and context. I've heard sequence of tenses is not required in such cases. Are past and present tenses interchangeable in both of them? Would it be correct to say:     (1) I suggested that the word zeitgeist is of German origin.   (2) The lecturer said the Pluto's orbital period was more than 200 years.


EM maximum likelihood estimation for Weibull distribution

Note: I am posting a question from a former student of mine unable to post on his own for technical reasons.  Given an iid sample $x_1,\ldots,x_n$ from a Weibull distribution with pdf $$ f_k(x) = k x^{k-1} e^{-x^k} \quad x>0 $$ is there a useful missing variable representation  $$f_k(x) = \int_\mathcal{Z} g_k(x,z)\,\text{d}z$$and hence an associated EM (expectation-maximisation) algorithm that could be used to find the MLE of $k$, instead of using straightforward numerical optimisation?


is multinomial expansion required to solve this infinite sum?

I cannot solve this infinite series by any means using polynomial ascending power expansions...  $$1+\sum_{i=1}^\infty(1/2)^i \prod_{k=1}^i\frac{3k-1}{3k}$$ Could somebody help me?


Rounding issue when adding certain floats

Addition of certain floats ends up with XXXX.XX00000000003  For Example:  convert(float,2896)+convert(float,268.98), convert(float,2896)+convert(float,268.96), convert(float,2896)+convert(float,168.97)   Resuts in:  3164.9700000000003  3164.98 3164.96 3064.97   I expected the first result to be 3164.97.  What gives?


I think I've established a self-contained dwarf fortress, and want to see what it would become without my intervention.  The problem is,  automatically stop the game, and I have to unpause it later manually. How can I keep the game running until the doom of my fortress?


readdir() beginning with dots instead of files

I have a little problem. I'm reading files from directory and it works, but it read two extra files on the beginning ...what is it?  for example, there is a list of files: "A348", "A348A", "A348B" and this is what i get: ".", "..", "A348", "A348A", "A348B"  ???  DIR *dir; struct dirent *dp; char * file_name; while ((dp=readdir(dir)) != NULL) {          file_name = dp->d_name;             }


'while' loop in bash: Not understanding the behaviour

I want to force people to pass a certain string after getting prompted: while [[ ! ${task} =~ "up|down" ]]; do     echo $task     read -p "Task to conduct? [up|down] " input     task=$input done  Although passing the correct string I am still getting the prompt: Task to conduct? [up|down] down down Task to conduct? [up|down] up up Task to conduct? [up|down]   What do I miss?


How can I make a SUM of cells that match a specific criteria?

Here's the excel table:    In B16 I'd like to insert the sum of all the cells in the range B1:B10 that have "*" on the right. In this case B16 = 10 + 2 + 7 + 9 = 28  How can I do this with a formula?  P.S. I'm using Excel 2010.


Book About A Boy Who Lives in a Children's Home with a Dark Secret

I was a child of ~9-10 years old when I read this back in the early to mid-nineties.  The book revolves around a boy who is taken to a home for children.  Strange things begin to happen and the boy realizes that the home has a dark side.  I honestly remember very little (except for the fact that I enjoyed it), but I do remember a demonic twist to the story (not necessarily a religious bent though.)  I recall gargoyle like creatures and that the children at the home began to disappear.  I believe that they would reappear later, though seemingly they had been brainwashed.  That's really all that I recall, I hope it's enough to spark someone's memory.


How to enable shutdown sound on ubuntu 12.04 LTS and up

I need a sound to play when I shutdown. In Kubuntu, there's shutdown sound. But Ubuntu, not anymore


Keyboard shortcut for switching between different keyboard layouts in Ubuntu Mate

Is there a pre-assigned keyboard shortcut for switching between different keyboard layouts in Ubuntu Mate?


Suppose that $V$ is a vector space, and $W$ is a subspace of $V$. If   $V$ is finite dimensional, then prove $W$ too must be finite dimensional.   It seems intuitively obvious that the dimension of $W$ must be less than or equal to that of $V$, but I am uncertain of how specifically to show this to be true analytically.  This question has been asked before (). However, there is not a great degree of explanation in the given answers. The answer which labels itself as a hint is most similar to my thoughts towards an approach to proving this particular theorem.  I was thinking that if $\exists n\in\mathbb{R}:n=\text{dim}(V) \implies \exists B = \{\vec{v}_1,...,\vec{v}_n\}$, a basis for $V$, with $n$ vectors $\vec{v}_1, ..., \vec{v}_1 \in V$. Since $W$ is a subspace of $V \implies \beta$, a basis for $W$, which has $m$ vectors in it can be constructed by removing $k\in\mathbb{R}$ vectors from $B$ such that $B\setminus\{\vec{v}_i,...,\vec{v}_j\}=\beta$ where $\vec{v}_i,...,\vec{v}_j$ are those $k$ vectors. This means a basis for $W$ has $m=n-k$ vectors in it, and by the definition of bases $\implies \text{dim}(W)=m$, and since $n-k \in \mathbb{R}$ and $n-k=m \implies m\in\mathbb{R}$. Thus $W$ is finite. $\square$  It seems like there may be some fault with this argument, though.


I am currently using Stack Exchange using Safari on my iPhone 4s. How can I upload a diagram to this site from the camera roll?


Preventing Mysqli Injection from my website

I have created a website however i have left preventing injection last because its what i have found most challenging.   Im now at the point where i need to convert all my quires which contain a variable or '$_GET' to a parameterised queries.   Here is an example of a couple of my queries :  SELECT   $storename = urldecode($_GET['name']); $ress = $conn->query("SELECT * FROM pages WHERE storename = '$storename'"); $page=$ress->fetch_array();   DELETE  if(isset($_GET['del'])) {     $id = $_GET['del']; $category = str_replace(".png","", $_GET['category']);   $SQL = $conn->query("DELETE FROM categories WHERE id='$id'");  $SQL = $conn->query("DELETE FROM categories WHERE category='$category'"); }   I have watched loads of tutorials read loads of post explaining this, however i am completely stuck with it, if anyone does not mind showing me how to prevent injection with these 2 queries that would be greatly appreciated. I could then look at how you have done it and apply this to other queries across my site.   Thankyou for any help


How to determine the angle of refraction when the medium has position dependent refraction index? Lets say that the angle of incidence on the glassy slab is $\theta_1$ and the ray goes through the slab and emerges on the other side. Refractive index of glass changes with position $n(x)$. The Length of the slab is $H$. How to determine the angle of refraction on the other side?  Some modification of Snell's law is needed?


I have a question regarding the interpretation of the relation $\Delta E \Delta t \ge 1$.   First, what is the exact meaning of $\Delta t$? We know that $\Delta E$ is calculated as the standard deviation of the energy distribution, but time is just a continuous parameter and there is no probability density associated with it. Can't measurements in non relativistic QM be done at precise time t?  Some undergrad texts explain this relation as "the longer you measure the energy, the less uncertain it is", but I feel this explanation is lacking. If we measure the energy of a particle, we should disturb it more, making $\Delta E$ larger!  Any input on this?


I am writing a project which makes use of the MS Chart for .net 3.5 utility.  However, either all users will also need to install this, or I need to package the dll with the program.  I can get Visual Studio to copy the dll to the folder with the program, but is it possible to make it embed the dll, so that there is only the one file?  I have seen several external programs out there, but surely there must be a way in Visual Studio - and would it work with a MS .net dll?


Views are not updated in search when a question was migrated

If I search for views:1..1, I get numerous results. Most of them have far more views than just one, however. Like 27 views sometimes.  You might assume caching causes newer questions to stay in the list, but none of the results are new at all (well, some may be new, but not most). I get a lot of stuff from 2015, for example.  While  would explain some of the results, it utterly fails to account for questions like this one: . It has a number of views in addition to two answers (one of which is a self answer). Or this question:  which has four up votes.  I didn't see the connection when I first asked this question, but these questions were all migrated from another site.    Here are searches for three big sites, which have enough migrations that just slip through the cracks:        It's a bit sad to know that numerous questions were migrated just to be ignored on another site...


What are the benefits of manning a subsystem?

In FTL, you can place crew members in various subsystems to gain bonuses. However, I don't know how to actually quantify those bonuses. The two that are least clear to me are:   Manning shields increases shield recharge speed. Manning weapons increases weapon recharge speed.   While I understand the general effect, I'm not sure how much of an actual increase I'm actually getting from these.   Also, in FTL: Advanced Edition, it looks like you can man the sensors and doors.  Finally, does manning it with multiple crew members give a larger bonus?


change Tkinter Entry's text when click button

The function need to be realized is: when the Tkinter button is clicked, an entry's text is changed. Here's  the code snippet:  import Tkinter as tk  def create_heatmap_button_callback():     path_entry.delete(0, tk.END)     path_entry.insert(0, "clicked!")      def main():     root = tk.Tk()     path_entry = tk.Entry(master = root, text = "not clicked")     path_entry.grid(row=1, column=0, sticky = tk.W)      create_heatmap_button = tk.Button(master = root, text = "create map", command = create_heatmap_button_callback)     create_heatmap_button.grid(row=2,column=0,sticky = tk.W)      tk.mainloop()     if __name__ == "__main__":     global path_entry     main()    and when clicked the button, here's the output:  NameError: global name 'path_entry' is not defined  What is the correct way to do this?


I'm currently running Ubuntu 14.04 LTS (not in a VirtualBox) with Chrome, and I have a interesting issue. Currently there is a solution to a similar problem listed  and , but my problem is just slightly different and none of the known fixes for the other problem are working.  My problem is that the mouse does not change when placed over things such as links where the mouse should turn into a pointing hand, or over text where there should be the I beam. Also, hover states and active states on website elements aren't being triggered either. However, if I'm currently scrolling or the mouse is held down, then everything works fine, but not while only moving the mouse.  I have tried:   Purge and reinstall of Chrome Running Chrome with --touch-devices=123 Trying to recreate this error on another system (Without success) Trying Opera (since it's also WebKit, which has the same issue)   NOTE: The other more widely seen bug has symptoms that aren't affecting me. For example, my scrolling and text selection is working completely fine.  Chrome Version 42.0.2311.90 (64-bit)  UA Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.90 Safari/537.36 FirePHP/4Chrome


Tikz: Shading a path without any filling

How can I shade a path witout filling? In particular, I wand to draw a curved arrow that starts colored blue and ends colored green, where in between it gradually changes its color. I can't find a way to shade a path without filling it.  The following code does not work, as it shades the filling area, although it compiles.  \documentclass{article} \usepackage{tikz} \usetikzlibrary{calc,automata,patterns,decorations,decorations.pathmorphing} \usetikzlibrary{fadings} \begin{document} \begin{tikzpicture}  \draw[path fading=south,very thick,top color=blue!80!white,       bottom color=green!80!white,->] (0,0) .. controls +(0,-1) and +(0,1) .. (1,-2);  \end{tikzpicture} \end{document}


Traveling with ESTA while having a F1 student visa

I am a student in the US on a F1 student visa, but I am currently in Europe. I will start my master's at the end of August, which means I am receiving a new I-20 that only allows me to enter 30 days prior to the start date.  I need to be back in the US June 25th for holidays. Can I get in the US in a Visa Waiver, which allows me to enter the US on June 25th as planned (as a tourist) and 30 days before classes begin, I will fly home back to Europe. A couple of days later I can then fly back to the US with the new dates on my I-20 for the Fall semester.  Is this possible?


In Tim Burton's Planet of the Apes... what is up with the final scene?  It was my favorite scene in the movie but is there actually a plausible explanation for it?


Could someone explain this notation and explain what this question is asking?

Show $\{0,1\}^V\approx\wp(V)$.   The $≈$ denotes that there is a bijection between $\{0,1\}^V$ and the powerset of $V$. However, I can't understand what $\{0,1\}^V$ is if $V$ is a set?


Okay, I like to use Aptitude for most of my program installation, due to its exceptional handling of dependencies (it's very diligent about removing unused libraries.)  Unfortunately, it appears not to be able to install Wine. The log is .  Now, I can usually get away with typing sudo apt-get install wine, and it will be fine, but the next time I run aptitude (I usually prefer it for programs that have many dependencies,) wine is removed.  Anyway, I didn't manage to figure out what was wrong (I could make out that it has something to do with an unresolvable dependency,) but I was hoping that somebody else could figure it out.


Can I choose which ads will be displayed to me on Stack Overflow?

The reason why is that I found SO Careers ads very distracting. Right now I'm not really looking for a job, but it's very difficult to ignore the good offers. I would like to see other kind of ads.


Change module settings stored in an array with drush

I would like to configure a module () settings with drush. This is the variable:  addtoany_nodetypes: Array (     [about_us] => about_us     [contact] => contact     [page] => page     [legal] => 0     [webform] => 0 )   So that, for instance:  [page] => page [legal] => 0   becomes  [page] => 0 [legal] => legal   But I am rather new at drush and I am at a complete loss. Thanks for your time.