Given $A$ and $B$ positive-definite matrices and $Q$ unitary matrix, prove that if $A = BQ$, then $A=B$. $Q$ is unitary, so $QQ^*=I$ If $A$ and $B$ are positive-definite, than $A=A^*$ and $B=B^*$. $A^*=(BQ)^*=Q^*B^*$ $A^2=AA=AA^*=(BQ)(Q^*B^*)=B(QQ^*)B^*=BIB^*=B^2$ $A^2=B^2$. I don't know how to use the fact that $A$ and $B$ are positive-definite to finish the proof.


Find all solutions of $x^2 \equiv 9 \pmod{85}$

I am asked to solve this problem, and I know how to solve congruences of degree $2$ modulo a prime $p$, but note that $85=5\cdot 17$ is a product of two primes. On the fly I managed to rewrite the expression as $(x-3)(x+3)\equiv 0 \pmod{85}$, and then since $(5,17)=1$, $5\cdot 17 | (x-3)(x+3)$ implies $5|(x-3)(x+3)$ and $17|(x-3)(x+3)$. Thus I tried expanding to two simultaneous congruences where the moduli are prime: $$x^2 \equiv 9 \equiv 4 \pmod{5}$$ $$x^2 \equiv 9 \pmod{17}$$ which I now know how to solve, for instance, the first congruence can be done by inspection as $x\equiv 2,3$ are the only such solutions (there are only four to check). I further conclude that $x=2+5k,3+5k'$ for $k,k' \in \mathbb{Z}$, and plug these values into the second equation: $$(2+5k)^2 \equiv 4+10k+10k+25k^2 \equiv 4+20k+25k^2 \equiv 4+3k+8k^2 \equiv 9  \pmod{17}$$ $$(3+5k')^2 \equiv 9+15k'+15k'+25k'^2 \equiv 9+30k'+25k'^2 \equiv 9+13k'+8k'^2 \equiv 9 \pmod{17}$$ thus $8k^2+3k-5\equiv 0 \pmod{17}$ and $8k'^2+13k' \equiv 0 \pmod{17}$ where $d=b^2-4ac = (3)^2-4(8)(-5)=13^2$ and $d'=b^2-4ac = 13^2-4(8)(0)=13^2$ thus from my book it states that both are solvable and with solutions: $$k = \frac{-3\pm 13}{16}$$ $$k'=\frac{-13 \pm 13}{16}$$ where $\frac{1}{16}=16$ is the inverse of $16$ modulo $17$ thus we get: $k\equiv (-3+13)\cdot 16 \equiv 10\cdot 16 \equiv 160 \equiv 7 \pmod{17}$ $k \equiv (-3-13)\cdot 16 \equiv -16\cdot 16 \equiv -(16)^2 \equiv -1 \equiv 16 \pmod{17}$ $k'\equiv (-13+13)\cdot 16 \equiv 0\cdot 16 \equiv 0  \pmod{17}$ $k' \equiv (-13-13)\cdot 16 \equiv -26\cdot 16 \equiv -8 \equiv 9  \pmod{17}$ and finally $2+5(7+17\ell) =37 +85\ell, \:\:2+5(16+17\ell) =82 +85\ell,\:\:3+5(0+17\ell) =3 +85\ell,\:\:3+5(9+17\ell) =48 +85\ell$ for $\ell \in\mathbb{Z}$. $x \equiv 3,37,48,82\pmod{85}$. I ran a computer check and it gave me the same four numbers so I guess it's correct. Is my approach correct? Maybe I was lucky with this method for this particular problem, but I'm wondering when would my approach break down? Because I've never seen congruences of degree $2$ where the modulus is not prime, let alone powers or multiples of primes.


How to disable or uninstall Microsoft Edge in Windows 10

Is there any possibility to completely disable the new Edge browser? The old IE could be disabled in Settings → Default Programs, but in Windows 10, the checkbox is missing for Edge.  Is there any way to get rid of Edge, or at least to disable all entry-points?


How does the wizarding economy work in Harry Potter?

Let me start of this question by clarifying some things about the population of wizarding Britain. According to the answers to this , nobody asserts that the population of wizarding britain exceeds more than a few thousand. Yet there seem to be thousands of people who work in the Ministry of Magic based on this excerpt from The Goblet of Fire about the Stadium for the Quidditch World Cup.     Seats a hundred thousand... Ministry task force of five hundred have been working on it all year.   We assume of course the country would have come to a standstill if a significant portion of employees work had to stop work for a year to work on a stadium so the total number of employees for the ministry should at least be several thousand.  So how can an economy work if almost everyone is employed by the government, i.e the amount government employees get paid in tax is less than the amount they earn so the government will forever be running a deficit, and since there doesn't seem to be an international banking cabal in the wizarding world (since the goblins run the banks) won't the government just go bankrupt?  Another point is familys like the Malfoys and the Blacks are super rich, without seeming to do any work at all, based largely on inherited wealth. But the only way that works is if people have always been fiscally conservative for generations, which would have led to a lack of money in the economy and thus bankruptcy (since the concept of inheritance tax doesn't seem real in the wizarding world). One could assume you accumulate wealth by running significant amounts of businesses, but literally every wizarding business seems to be located on Diagon/Knockturn alley or Hogsmeade - and most if not all seem to be independently run Madame Malkins - Robes, Floreans Ice Cream, Pudifoots Teashop, Olivanders wands etc. and not run by some conglomerate owned by one of these rich familys, so how do they make there money?


Need to know about this separate unidentified drive. (snapshots included)

The drive in red. I don't remember when I saw it first time. I thought it was a backup drive back then. Can I remove this partition? I can provide any further details if needed


Why was there apparently no knowledge of the missing ship in the Typhon Expanse?

In the TNG episode "", we are treated to the following line of dialogue...three times.       "Captain's Log, Stardate 45652.1. The Enterprise has entered an area of space known as the Typhon Expanse. We are the first Starfleet vessel to chart this unexplored region."    This strongly suggests that no Starfleet ship has ever actually been into this part of space.    Yet the very end of the episode shows that a Starfleet ship WAS in this section of space, Specifically the USS Bozeman, years ago. Proven when it emerged from a temporal loop just in front of the Enterprise.    How do we account for this inconsistency - saying that the Typhon Expanse has never been charted, and yet there clearly being a federation ship already in the Typhon Expanse?


Mountain Bike has 26 x 2.125 Tires on, Can I Fit 26 x 1.95?

My mountain bike has 26 x 2.125 tires on it and I am ordering new 26 x 1.95 tires.   Will these be okay to use? What issue might this cause? Or will the difference be negligible?


I have two content types, the first is Homepage and the second is SLider. The Slider content type has multiple fields like title, ink, and image. In the homepage content type, I have an entity reference field referring to the slider content type with multiple selections. I've created a template in my custom theme as node--home-page.html and want to get the sliders fields values, All is okay with me except the image. I cannot get the image URL.  My code:-  {% for slide in node.field_hoeme_slideshows %}         {{ kint(slide.entity.field_home_slide_cta.uri) }} {# This is working #}         {{ kint(slide.entity.title.value) }} {# This is working #}         {{ kint(slide.entity.field_home_slide_snippet.value) }} {# This is working #}         {{ kint(slide.entity.field_home_slide_image) }} {# ****** This is not working *****#} {% endfor %}


If $X$ is measurable space, $f : X\to [-\infty,+\infty]$, function such that $f^{-1}([-\infty,r))$ measurable for all rational numbers $r$,prove than $f$ is measurable  I know that $f$ is measurable iff set $\{x\in X : f(x)<a\}$ is measurable for all $a\in \mathbb{R}$ but for $a\in\mathbb{Q}$ I don't know how to proceed.


Make subsection visible in local TOC only, not in Main TOC

I am writing a large article type document with a series of complex appendices in it.  I have included a local table of contents with each appendix that lists the sections and subsections within that specific appendix (the local TOC for Appendix A lists only that appendix's subsections, etc) using tools from the etoc package.  What I would like to do is have my appendix sections contain numbered subsections/subsubsections, but have the subsections/subsubsections only appear in the appendix local TOC. However I still want the appendix sections to appear in the main TOC.  Here is a rough approximation of my setup:  \documentclass{article}  \usepackage{tocloft} % Adds tools for TOC customization \usepackage{etoc} % Local toc \usepackage[titletoc,title]{appendix}  \begin{document}    \setcounter{tocdepth}{3}   \tableofcontents    \section{First section}     \subsection{a Subsection}   \section{Second section}     \subsection{a Subsection}     \subsection{Another Subsection}    \begin{appendix}     \section{Appendix A} % <- I want this to appear in the main TOC       \etocsetnexttocdepth{2}       \localtableofcontents       \subsection{Appendix Subsection} % <- I want this to appear in the local TOC, but not the main TOC   \end{appendix}  \end{document}   And the output:


I was updating the clamav antivirus defenitons with the sudo freshclam command and the output was:   ERROR: /var/log/clamav/freshclam.log is locked by another process ERROR: Problem with internal logger (UpdateLogFile = /var/log/clamav/freshclam.log).


Can a person who influences others lives be killed by a Death Note?

There's a rule, that a death note entry can't lead to another's dead. So here is a bad example:  A has a bomb, which will explode, if his heart stops, (this bomb is extremely accurate, so if his heart even stops for one second, the bomb will explode.)   B has a death note, and wants to kill A.   A, has a hostage, who is close to him, and if the bomb will explode, the hostage will also die.   B writes A's name in its death note. Will A die, or will he survive, because if he dies, the hostage will also die?


How is Pandemic Legacy impacted by playing with two characters?

What are the mechanical/strategic differences in playing Pandemic Legacy: Season 1 with just two characters, as opposed to three or four?  If discussing Season 1 spoilers is unavoidable, please remember to use the spoiler notation (>! hidden text) and clearly mark them.


How to get the spaces properly on the x axis, how to place the y values on the corresponding bars?

I am using the following commands to draw a barchart.  \begin{tikzpicture}         \pgfplotstableread{ % Read the data into a table macro             Label       Female   Male               2006-2008    3     1              2007-2009    2     0             2008-2010    9     2             2019-2011    3     3             2010-2012    11    1              2011-2013    6     0             2012-2014    12    7             2013-2015    10    7             2014-2016    10    3         }\datatable          \begin{axis}[         compat=newest, %Better label placement %        axis on top,         ybar stacked,   % Stacked horizontal bars         xmin=0,              % Start x axis at 0         ymax=25,         ymin=0, ylabel={Number of students}, xlabel={Batches},bar width=10pt,         y axis line style={opacity=0},         yticklabels={\empty},         ytick style={draw=none},enlarge y limits={upper, value=0.2},         xtick=data,     % Use as many tick labels as x coordinates         enlarge x limits = .2,         xticklabels from table={\datatable}{Label}  % Get the labels from the Label column of the \datatable         ]         \addplot [fill=yellow] table [y=Male, x expr=\coordindex] {\datatable};    % Plot the "First" column against the data index         \addplot [fill=green!70!blue]table [y=Female, x expr=\coordindex] {\datatable}; %        \addplot [fill=red!80!yellow] table [y=Third, x expr=\coordindex] {\datatable}; \legend{Male,Female}         \end{axis}         \end{tikzpicture}   I got the picture as,     How to get the spaces properly on the x axis? How to place the y values on the corresponding bars? How to rotate the label 90 degree? How to take out the ticks on the top? Is there any other way of representing this data(two dim only)? (optional)   I hope all the questions can be answered in a single answer?


While asking new question, what is the criteria for a tag to become visible as 'suggested tag'?

I  have recently wrote a few questions for Gerrit code review system and with each question being written, I could clearly see, that only  tag appears among suggested tags:        The  tag has now over 400 questions and I put that string in many places in my question, but even though it doesn't appeared as suggested tag.  So: what conditions must a tag meet to become visible among suggested tags?  Additional information:   For past five-six questions about Gerrit,  was the only tag that was visible among suggested tags. A few minutes ago, I've asked another question about Gerrit, and this time I saw whole bunch of suggested tags, including: , , , , and , though neither GitHub nor SVN haven't been mentioned even an once in my question. As in above, just added new question, this time for Notepad++ and  tag wasn't among suggested, though it has 1800+ questions tagged and though this name is mentioned few times in question body; on contrary,  and  tags were suggested, though there isn't even a trace of them in question body.   This case (my question) becomes more and more interesting...


Suppose we have a sample of size n= 9, where the sum equals 27, and the sum of the squaredvalues equals 113. Sample mean is 27/9=3 and mean of squared values is 113/9 = 12.56 Can we then say that the sample variance $S^2 = E(\overline X^2) - E(\overline X)^2 = 12.55 - 9 = 3.56$ ?


"You not only couldn't fix it but even damaged it more!"

Suppose you want to fix your brother's bicycle, but this time it seems that you cannot do it and at the end of your work, you find that you have caused an extra damage to that bicycle, too! :)      We have an proverb which says:" You wanted to shape/fix someone's eyebrow but you blinded their eye!"   Is there any idiom or proverb that can convey the same connotation?


If $\sum a_{n}$ is convergent, prove $\sum \frac{a_{n}}n$ is also convergent

If $\sum $$a_{n}$ is convergent, prove  $\sum \frac{a_n}{n}$ is also convergent.  I would say that $a_{n}\geq \frac{a_{n}}{n}$ so being $a_{n}$ convergent, $\frac{a_n}{n}$ also has to be convergent.  However, I think it is not enough...


Can I estimate tyre pressures on a road bike?

Can I estimate my road bike tyre pressures by pressing my thumb into the tyre? I don't have a tyre pressure gauge, and feel that the tyres on my new Merida Scultura are pumped too hard.


At "intramfs" what command to boot "fsck" to clear booting fault ? I have changed the computer battery and the boot process stops at a fault which ends with the prompt "initranfs". It says;  /dev/sda1 ; UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY fsck ended with status code 4.  Can you tell me what to type from here, please ? John Scott.


I need some help understanding this proof:  Prove: If a sequence converges, then every subsequence converges to the same limit.  Proof:  Let $s_{n_k}$ denote a subsequence of $s_n$. Note that $n_k \geq k$ for all $k$. This easy to prove by induction: in fact, $n_1 \geq 1$ and $n_k \geq k$ implies $n_{k+1} > n_k \geq k$ and hence $n_{k+1} \geq k+1$.  Let $\lim s_n = s$ and let $\epsilon > 0$. There exists $N$ so that $n>N$ implies $|s_n - s| < \epsilon$. Now $k > N \implies n_k > N \implies |s_{n_k} - s| < \epsilon$.   Therefore: $\lim_{k \to \infty} s_{n_k} = s$.   What is the intuition that each subsequence will converge to the same limit I do not understand the induction that claims $n_k \geq k$


how do you estimate the mortality rate of the corona virus?

Disclaimer: I initially posted this question on math.stackexchange.com, but a user there suggested I should post it here instead.  I've seen mortality rates for the coronavirus reported for different countries. For example,  gives the worldwide mortality rate as $3.4\%$. Under the estimate it says 'Globally, about $3.4\%$ of reported COVID-19 cases have died[...]' However, this seems to me to be a fundamentally flawed estimate. I can think of so many problems.  First of all, people don't just die  instantly with some probability when they get infected. I can't find a source for this number right now, but I've read it's usually about 14 days from when you get infected to when you die or recover. Anyway, the exact number isn't too important, just that it is defientely not 0 days. So then, you would have to modify the formula to something more like $\text{mortality rate} = \frac{\text{deaths}}{\text{cases 14 days ago}}$, right? However, this is still not good enough. We can't just plug in the number of reported cases, as that grossly underestimates the real number of cases. Most countries around the world have literally just stopped testing people who are not 'at risk'. If they are just using the number of deaths due to the virus and the reported cases, then they will get a number that is way too big. Now, let's say that they think about this, and instead they only include the deaths of people that had been tested for the virus to account for this. Now, they have a biased sample, because, heuristically, only the people who are the most sick will be tested, while the people who are young and healthty and show no symptoms yet are not tested. So both of these methods will give a wrong mortality rate. I have also seen a formula where you calculate the mortality rate like this: $\text{mortality rate} = \frac{\text{deaths}}{\text{deaths + recovered}}$. This formula makes more sense to me than the others, but  it seemingly gives a much higher mortality rate than these other methods, whilst I would have thought that the others methods were flawed in such a way that they would give too high a mortality rate, not too low.  Next, I thought that maybe they have just calculated the mortality rate for reported cases, and rolled with that, being careful not to apply that anywhere it would not be valid. However, I found the following method to estimate the number of real cases today in  by Tomas Pueyo.  If we assume for now a death rate of $1\%$, then we can use that to estimate the real number of cases based on the number of deaths. So, if we have $D$ deaths today, and the mortality rate is $1\%$, then we can assume about $100$ people had the virus $14$ days ago. Then, using a made up doubling period of about $5$ days (there is real data on this of course), the number of cases will double about three times in those $4$ days, so the real number of cases today is about $100 \times 2^3 = 800$.  This method makes sense to me, but only if we use the real mortality rate. not the one that based on a biased sample. Aside from this one quirk, I haven't found anything else I think is wrong in that article, and I've seen nothing but praise for the analysis Tomas Pueyo did in this article. Notably,  made a video on this method, using this method.  The only reliable method I can think of to calculate the real mortality rate right now would be to conduct an experiment in which you infect a group of volunteers, and then you calculate the mortality rate from only that group. That way, you would get an unbiased sample. However, this experiment would obviously be incredibly unethical and I doubt it has been done.  Does anyone know how to estimate the real mortality rate during the epidemic?


What are the criteria that makes metaphysics metaphysics? In my understanding, metaphysics literally means beyond philosophy, but what are the criteria that makes something be metaphysical? Is the only criteria the fact that it has to be beyond what philosophy can uncover?


I recently noticed that words are broken/split for , e.g.:   responsiveness enabled          responsiveness disabled          Could you please not break words in the question title?


Question about the calculation of likelihood function

I am looking at the answer on this thread:   Here as I understand that the likelihood function is given by:  $$ L(\theta) = \frac{1}{\theta} \quad \mathrm{in\ range}\ [0, \theta] $$  First, I am confused by the notation in the reply in the thread I posted. So the likelihood is defined as $U(0, \theta)$. I am confused as to why the parameter $\theta$ appears in the support of the uniform distribution. Should the support not be just constants like $U(0, +\infty)$?  [EDIT]: As pointed out below $U(0, +\infty)$ is not possible but I was still expecting something like $U(0, 1)$ for standard uniform distribution or something of the form $U(a, b)$. In any setting, $\theta$ is unknown so how can it be the parameter of the uniform distribution?  Second, when we observe $Y=1$, why does the likelihood become  $$ L(\theta) = \frac{1}{\theta} \quad \mathrm{for}\ \theta > 1 $$  Why now $\theta > 1$ instead of $\theta > 0$


Command-line keychain access not showing any results

I have been trying to learn to control my computer through command-line, and keychain access is what I am trying now. I have been using the security command, and attempting to get my wifi password (I know it of course, but getting it through terminal is the challenge). From what I have read on other Stack Exchange pages () and ,   security find-generic-password -a Netgear25 -s Airport -g   should come up with a list of information, including the password. But there is no output at all. So the 'result' is:   Host:~ Batman$ security find-generic-password -a Netgear25 -s Airport -g Host:~ Batman$   nothing.   security 2>&1 >/dev/null find-generic-password -a Netgear25 -s Airport -g security    does the same thing, no result. What am I going wrong?  EDIT  I think I should clarify - I am doing this remotely for a challenge, and obviously when I do it on the computer itself it comes up with the Authorisation Dialog Box. Remotely though, the dialog box won't come up. So the real question is how to authenticate it remotely (using sudo also comes up with no result).


I'm trying to add boxes around my links like in   but I don't get the boxes only the number. \documentclass[a4paper,UKenglish]{article} \usepackage{graphicx}  % \usepackage[utf8]{inputenc}  \usepackage{amsmath,amssymb,amsthm} \newtheorem{theorem}{theorem} \usepackage{comment}        \usepackage{caption}  \usepackage{subcaption}   \renewcommand{\thesubfigure}{\roman{subfigure}}   \usepackage[ruled,vlined,algo2e]{algorithm2e}  \usepackage[utf8]{inputenc} \usepackage{xcolor}  \usepackage{hyperref} \hypersetup{backref=true,            pagebackref=true,                    hyperindex=true,                     colorlinks=false,                     breaklinks=true,                     urlcolor= black,                     linkcolor= blue,                     bookmarks=true,                      bookmarksopen=false,     filecolor=black,     citecolor=blue,     linkbordercolor={1 0 0} }  \AtBeginDocument{\hypersetup{pdfborder={0 0 1}}}% <-----------   \begin{document}     \begin{theorem}\label{lemma1} adfsdfadf \end{theorem}  \ref{lemma1}     \end{document}


How can I use Flash Player now that it's no longer supported?

I know that Adobe Flash Player is discontinued for Android devices, but is there an alternative way to continue using Flash on an Android device?  I have the APK of Flash Player 10, but I would like to use the most recent version.


eth0 changed to eno1 and 70-persistent-net.rules is missing

I booted up Ubuntu, noticed I had no internet.  Ran ifconfig, eth0 is now eno1 and has no IP.  I ran dhclient eno1, no DHCP server found.  Went to check 70-persistent-net.rules, it's gone.  I rebooted and tried to regenerate it, no luck.  I am kind of a linux noob and this problem is driving me crazy.  oh, and /etc/network/interfaces only has lo, no other interfaces listed.  I haven't pasted any command outputs because as I said, no internet.  If need be I will manually type out terminal outputs, but I don't want to have to do excessive typing.  Any and all help is greatly appreciated, thanks.  UPDATE: WiFi is working now, although it cuts out every 10-15min and the interface has the be brought down and up to reconnect.


How do I restrict JFileChooser to a directory?

I want to limit my users to a directory and its sub directories but the "Parent Directory" button allows them to browse to an arbitrary directory.  How should I go about doing that?


Export excel values into playing card template

I have very limited experience with photoshop (only use it for sketching/coloring). I am currently creating a word-based board game and have an excel sheet with 500 or so words.   Is there an easy way I can batch these words onto a playing card template in photoshop? Or would I have to copy and paste each word from the list onto the template by hand?


Java .contains cannot be used with charAt

java: incompatible types: char cannot be converted to java.lang.CharSequence  boolean checkParentheses(String str) {     Deque<Character> stack = new ArrayDeque<>();        String k = "({[";     String s = ")]}";     for (int i = 0; i < str.length();i++ ) {         if (k.contains(str.charAt(i))) {             stack.push(str.charAt(i));         } else if (s.contains(str.charAt(i))) {              if (matching(stack.peek()) == str.charAt(i)) {                 return true;             }         } else {             return false;         }     } }    what should I use instead of contains?


Template typedef of function pointer in c++

Imagine I have a template class, where I've defined typdedef of function pointer to BaseClass function, that returns T and has no arguments:  template <typename T, typename BaseClass> class TConnectionPoint {     typedef   T (BaseClass::* PConnectionFunction)();     private:        PConnectionFunction _func;     public:        T Call(); }   This template has method Call():  template <typename T, typename BaseClass> T TConnectionPoint<T,BaseClass>::Call() {     return _func(); }   The problem appears when I try to execute Call() function - VS2013 send me this error, which is a little confusing me:     term does not evaluate to a function taking 0 arguments   What I'm doing wrong?


What is the intuition behind Dirichlet distribution?

looking for explanation on similar lines


Work done by a person climbing stairs, who or what does the work?

I've seen other questions like this but didn't really see any answers.  When a person climbs stairs, the object is the person. Yet we say the person did work...how so? Doesn't work mean an external force had to be applied over a distance to make an object have a change in KE or PE?  Isn't the work more less from the muscles of the person. The stairs didn't do work. Then really isn't the work internal work done, where the work done is causing and changing their chemical energy to kinetic?  I get work done on a box or more complex systems. But who or what does the work in climbing stairs if it is the person themselves in the system. Why don't physics books explain these type of examples. Thanks in advance


How to compute moments of log normal distribution?

The computed moments of log normal distribution can be found . How to compute them?


correct use of hyphens to connect two words

Should I use a hyphen to connect the following words? What is the general rule about that?  environment friendly  -->  environment-friendly frontend   --> front-end backend   --> back-end speedup   --> speed-up


I would like if there is a way to capture in a log file all the transfer file activities in a given time period. Let me give you an example. Let's say that on 16 Aug 2017 13:35 I copy/move a file/folder from my Mac to a usb device without giving any special arguments when using the cp/mv commands (in any case copying/moving files/folders can be achieved through GUI).   Is there any text file on the Mac which records the activity history (such as copying/moving files/folders)? I would like this text file to include information in a way like:  16 Aug 2017 13:35 path/to/folderA was copied to /path/to/usb/stick/ or something similar.


Can abilities with no "tap/untap" cost be activated while a creature has summoning sickness?

From the MTG rules:     302.6. A creature's activated ability with the tap symbol or the untap symbol in its activation cost can't be activated unless the creature   has been under its controller's control continuously since his or her   most recent turn began. A creature can't attack unless it has been   under its controller's control continuously since his or her most   recent turn began. This rule is informally called the "summoning   sickness" rule.   Do I correctly understand then that other abilities, such as the 's ability can be used immediately after being placed onto the battlefield?     {1}{B}, Sacrifice a creature: Target player loses 1 life and you gain   1 life.


arXiv: "Option clash for package hyperref." when there are no options!

Here is a MWE:  \documentclass{article}  \usepackage{hyperref}  \begin{document}  a  \end{document}   When I compile my document on , I get the following errors:  ! LaTeX Error: Option clash for package hyperref.  ...   l.6 \begin {document} ?  ! Emergency stop. ...   l.6 \begin {document} No pages of output. Transcript written on arXivSubmission.log.   Seems bizarre that having a single package in the preamble causes an error.


How to use a nickname to identify my posts?

I would like to use a nickname to identify my posts, not a user + number as shown when I log in.   How do I cause the log-in process to log me in as my nickname and not the user + number id (user178183) you have assigned?  Is this perhaps 'OpenIDs are wrongly identified'?  By the way, my nicknames are intrader or mozillanerd, depending on the occassion.


I can no longer accept answers for my question as I don't work in that project

There are a few questions I've asked which took much longer time to get a proper solution. But I can no longer use/test those solutions due to different reasons. So those questions remain unsolved. Is it possible for the community to take over those questions so that if any one encountering the same issue can test the suggested solutions and accept the working solution.


Hints for a complex limit: Prove if $\lim_{z \to \infty} f(z)/z = 0$ then $f(z)$ is constant.

(To clarify, I would just like a hint. Please do not give me the answer to this problem. ) The solution to the following problem has really evaded me here:  Problem: Assume that $f$ is entire and that $\lim_{z \to \infty} f(z)/z  = 0.$ Prove that $f(z)$ is constant.  My Thoughts and Work So Far: We know that proving that $f'(z) =  0$ or that for some fixed $c \in \mathbb{C}$, $f(z) = c$ for all $z\in \mathbb{C}$. My first approach was to use Liouville's Theorem; If I could could show that $f$ is bounded then I am done. Since $\lim_{z \to \infty} f(z)/z  = 0$, for all $\varepsilon > 0$ there exists a $N \in \mathbb{C}$ so large that if $z \geq N$ then $|f(z)/z| \leq \varepsilon$. Thus, if $C_R$ is the circle of radius $R$ centered at the point $z$, then, as long as z is large enough by Cauchy's Inequality $$ |f'(z)| \leq \frac{1}{2\pi i} \oint_{C_R} \frac{f(\zeta)}{(\zeta - z)^2}\ d\zeta \leq \bigg | \frac{1}{2\pi i} \bigg | \oint_{C_R} \bigg | \frac{f(\zeta)}{(\zeta - z)^2} \bigg | d \zeta \leq \frac{1}{2\pi}  \frac{|\zeta|\varepsilon 2\pi R}{R^2} = \frac{|\zeta|\varepsilon}{R}.  $$  Now taking the limit as $R \to \infty$ (which to me says, "let our circle around our point z dilate to an infinite radius so that it covers all of $\mathbb{C}$)  $$|f'(z)| \leq \lim_{R \to \infty} \frac{|\zeta|\varepsilon}{R} = 0.$$  Thus $f'(z) = 0$ and $z$ was arbitrary, so $f$ must be constant.   Why I Think Im Wrong: I say $z$ was arbitrary, but really it is "any $z \geq N$" which really isn't all that arbitrary.   This is where I am stuck. Am I right, wrong, close, or totally lost? Any hints would be great.  Edit: I am very sorry but I accidentally posted this before I was done typing the problem.


Evaluate:  $$\int_0^1 \frac{1-x}{(1+x)\log(x)}\, dx$$  Wolfram alpha gives an answer of $\log(2/\pi)$, but I have been unable to prove this. Help appreciated.


select single item from a collection : Python

I created a utility function to return the expected single item from an generator expression  print one(name for name in ('bob','fred') if name=='bob')   Is this a good way to go about it?  def one(g):     try:         val = g.next()         try:             g.next()         except StopIteration:             return val         else:             raise Exception('Too many values')     except StopIteration:         raise Exception('No values')


This is the method code:  public static void printMatrix(int[][] m, int i, int j) {     if (i == m.length ||j==m.length) {         System.out.println();     } else {         System.out.print("[" + m[i][j] + "]");          printMatrix(m, i, j++);         printMatrix(m, i++, j);     }  }   I don´t know why it just prints the first position of the array until a StackOverFlow error.  Thanks for the help.


If I have a folder with the following file names:  cluster_sizes_0.txt cluster_sizes_1.txt cluster_size_2.txt   etc.  Each file contains a single column of values.  Is there a command within linux such that I could combine all files into cluster_all.txt?  The first column in this new file would correspond to cluster_sizes_0.txt, the second column would be cluster_sizes_1.txt etc.  There could be as many as 200 cluster txt files, but it changes for each folder. I am looking for a way to combine these files, instead of copying each one by one.  Also, I need to make sure they are pasted into the file in order. This may have some issues with the numbering system, since I only include single digits if below 10.  For instance:  paste cluster_size.* > cluster_all.txt doesn't paste them in order due to the numbering. How can I fix the numbering without manually changing all of them?


Change the brightness adjustment interval

So whenever I hit my dim/brighten keys on the keyboard, a notification bubble pops up with the screen brightness. All that's fine, but I would like to be able to change how much the brightness changes with each key press.  For example, right now it takes just 5 presses to go from the completely dark to the brightest setting. However, I know from the "Brightness/Lock" setting that the screen is capable of much smaller intervals than this.  Is there a way to change how much the brightness jumps each time the keys are pressed?


How do you echo a 4-digit Unicode character in Bash?

I'd like to add the Unicode skull and crossbones to my shell prompt (specifically the 'SKULL AND CROSSBONES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", . In addition to the answers below it should be noted that, obviously, your terminal needs to support Unicode for the output to be what you expect. gnome-terminal does a good job of this, but it isn't necessarily turned on by default. On macOS's Terminal app Go to Preferences-> Encodings and choose Unicode (UTF-8).


Show that $\int_0^ \infty \frac{1}{1+x^n} dx= \frac{ \pi /n}{\sin(\pi /n)}$ , where $n$ is a positive integer.

Using residues, try the contour below with $R \rightarrow  \infty$ and  $$\lim_{R \rightarrow  \infty }  \int_0^R  \frac{1}{1+r^n}  dr \rightarrow \int_0^\infty  \frac{1}{1+x^n}  dx$$    I've attempted the residue summation, but my sum did not converge.


Different meanings for phrase "off the regular price"

What is the correct way to say a product can be bought with a discount of 30%?  Is it: “Buy this by 30% off the regular price.”?  What I want to say is that a 30% discount is being given, so the product will cost 70% of the regular price.  There seems to be a difference between of and off. Will this wording be misunderstood to mean that the product can be bought by 30% of the regular price instead of 30% “off” the regular price?   How do I say it correctly and without creating doubt?


Can I conclude I have outliers when no coefficients are significant but f-test is significant?


Why does Gandalf, during the siege of Gondor, imply that he cannot defeat the Black Captain because "not by the hand of man will he fall" ?  Isn't Gandalf not of mankind and thus not a man? Or does his incarnation qualify him as one?  Also, after the battle, Gandalf says that "The Captain of our foes is gone, but not without loss and bitter woe that I might have been able to prevent".  In summary: 1) Is Mithrandir a man? 2) Does Gandalf think that he can defeat the Black Captain, or not?  EDIT: clarification - part 2 is asking if Gandalf believes the prophecy applies to him, not if he actually can defeat the Witch-king.


How do I disable the mail app from keep appearing on Mac when I'm in full-view of a screen?

From everywhere I’ve read, they say that I’m suppose to uncheck the “Prefer opening messages in split view when in full screen” option and it’ll go away but it doesn’t. Any help?


Hi need some help with this problem:   Assume $f : \mathbb{R} → \mathbb{R}$ is a continuous function, satisfying $f(α) =  f(β) +f(α −β)$ for any $α, β ∈ \mathbb{R}$, and $f(0) = 0$. Then $f(α) = α f(1)$.  any hints, thank you.


Possesive pronoun to use with the interrogative pronoun

When using the interrogative pronoun, 'who', what would the possessive form be?  'Who checks X letterbox every day?'.   I feel it ought to be 'his' but some people I know claim it should be 'their', which to me seems to contradict the singular form of the verb 'check'.   'Who checks his letterbox every day?' is what I would say naturally. 'Who checks their letterbox every day?' sounds a bit off to me.  Looking on the internet doesn't really return anything useful, only the use of 'their' as a singular pronoun, which seems to be somewhat popular a topic.   Note, this is specifically regarding the interrogative pronoun; I understand the debate about his/her/their/ones in other circumstances but I want to know whether the same can apply to 'who' or 'whom'.


Anybody knows how to create custom text fields on salesforce.com objects using apex?


Find the limit $ \lim_{x \to \infty} \frac{e^{x}}{(1+\frac{1}{x})^{x^{2}}} $

Find the limit $$ \lim_{x \to \infty} \frac{e^{x}}{(1+\frac{1}{x})^{x^{2}}}. $$  I know that the limit is of indeterminate form type $\frac{\infty}{\infty}$, but it seems using L'Hopital's rule directly does not help here.  Do I somehow use the fact that $\lim_{x \to \infty} (1+\frac{1}{x})^{x}=e$?


How to benchmark maxCache 3.0 with SSDs?

We're a software development company and previously outsourced the HW side of business but now we're looking into building our own private cloud. We recently purchased a few servers, one of which is supposed to act as a central storage. The specs are as follows:   Chassis: CSE-826BE16-R920LPB Motherboard: Supermicro X10SLL-F CPU E3-1200v3,Intel C222, 2GbE, Up to 32GB DDR3 ECC,2xSATA3,4xSATA2, 4xDDR3 IPMI 1x CPU Intel Xeon E3-1220v3 - 3.1GHz, 8MB cache, 4core, HT, LGA1150, 80W 1x heatsink SNK-0046A4 Activ 2U 4x 8GB Samsung M391B1G73QH0-CK0 1600MHz DDR3 ECC Unbuffered 2R×8  2x SSD 80GB Intel DC S3500 Series 2,5" SATA3, read 340 MB/s, write 100 MB/s  10x HDD 2TB Seagate Constellation ES.3 ST2000NM0023 3,5" SAS2, 7200rpm, 128MB   The Seagate drives are set up as RAID 6 array. The SSDs are in RAID 1 and act as maxCache container which we turn on and off using maxView Storage Manager.  My first question - does this configuration make sense for a central storage of a private cloud where we plan to have other 3 compute nodes with two CPUs and lots of RAM on them?  My second question - would a similar configuration with less HDDs make sense for a MySQL database server for a reporting system with many concurrent requests? Or would it make more sense to use the SSDs for MySQL's temp space where it creates temporary tables.  And now for the main question... I tried to measure performance of this server with and without SSD cache (maxCache). The best tool I came across was iozone (iozone -a -g 8G) which produced these charts: . I am totally puzzled as it looks like the performance with maxCache is in most cases lower than without it.  I was wondering if iozone is a good way to test for real-life scenarios or if I'm doing this all wrong.


On bash in windows 10 , I can navigate to the desired file and for now I can edit them with vi, but for ease of use I want to edit them with text editor like gedit or sublime text. But I can't do that e.g if I try to open a file with gedit it says "Gtk-WARNING **: cannot open display:"


Given that $p(x)$ is a polynomial of the form $x^n + a_{n-1}x^{n-1}+ ... + a_1 x + a_0$, where $a_1, a_2, ... , a_n$ are integers

I am given that $p(x)$ is a polynomial of the form $x^n + a_{n-1}x^{n-1}+ ... + a_1 x + a_0$, where $a_1, a_2, ... , a_n$ are integers.  I am also given that $x = \frac{a}{b}$, $\gcd(a,b) = 1$ (thus $\frac{a}{b}$ are in their lowest terms), $p(\frac{a}{b}) = 0$, and $|b| > 1$  Use the factorization of $b$ to contradict the assumption that $a$ and $b$ are coprime.   We have been using the Bezout theorem quite a bit in class so I first started off with that then took it to the power of $n$, so $(ax + by)^n$, then attempted to use the binomial theorem in an attempt to group the $b^i$ terms together, but after that I am unsure how to proceed in proving that $a$ and $b$ are coprime.  Any hint or help is appreciated. Thank you.


Do I need a separate SSL certificate for a DNS redirect?

I am implementing a multi-tenant application where my application hosts and serves technical documentation for a tenant's product.   Now, the approach that I was considering was - I host the documentation at docs.<tenant>.mycompany.com and ask my tenant to setup a CNAME DNS record to point docs.tenantcompany.com to docs.<tenant>.mycompany.com.   I want to the site to be SSL-enabled with my tenant's certificate. I wanted to understand if I my tenant company has a wildcard SSL certificate, will it work with this setup or will a new SSL certificate have to be purchased for docs.tenantcompany.com?


How does a transformer transmit power from the primary to the secondary?

I'm trying to get my head wrapped around transformer operation and in the process regretting the times I snoozed in my Electromagnetics class as a EE student back when I was a lad :)  I'm looking for an intuitive understanding, but not just an analogous one. I'd like it to be grounded in the actual physics of what's happening. I've found several excellent sources on the web, but they all seem to skirt this question.  I've come across a few interesting hints and am now tantalizingly close, I think, but still yearning :)  Fact 1: Although varying sinusoidally, the "peak-to-peak" flux, so to speak, in a transformer's core is essentially constant (for a given voltage applied to the primary), regardless of the load.  My intuitive hypothesis was that variation in the "strength" of the flux was what transferred the energy from the primary to the secondary, but this fact would seem to contradict that theory. I had thought that the primary makes a bunch of flux based on the current flowing through it and the secondary sucks it up to make current of its own. No dice, it seems.  Then of course there's the fact that the formula for flux involves only voltage, time (frequency), and turns :)  Fact 2: The current in the primary is (approximately) 90 degrees out of phase with the voltage at no load, and approximately aligned in phase at full load.  This fact seems very promising and also curiously satisfying. It would imply that the Volt-Amps (VA) of the primary is constant and only the power factor changes as the current load on the secondary increases.  But I still don't get how the energy is actually being transferred. It seems vaguely like the flux is just there as an energy conductor or something and some other phenomenon is actually doing the energy transfer bit.  Can someone see what I'm missing and explain what's actually happening in there?


Ninja-edit if your comment/answer is less than one minute old

If your comment is less than one minute old at the time you click submit (meaning, not when you click the edit button) the little pencil will not come up:   This is because if your comment is less than one minute old the most likely reason you are editing it is to fix a grammatical error. Good idea?


My SSD free space dissapeared. What should I do?

I have a problem with SSD free space.  It says, that free space on drive C is around 5GB but  it says, that I used only 44GB. If i'm not bat at maths there is still around 75GB of free space but my PC says, that I have only 5GB.  and I'm looking forward for your answers.  Explanatory Notes :   "Všetko v priečinku C:" - everything in C: folder  "Využité miesto" - used space  "Voľné miesto" - free space


The question states:    I'm not sure what to do here. I used the geometric sum to do $2^{-n}$, but I can't think of a way to sum $\sin(n\theta)$ to get the required RHS.    Further working     Apologies for maybe being slow or missing something obvious here... I don't know how to get it into required form.


I want to see the method for computing the following integrals: $$\int_0^\infty\ln(x)\sin(x^2)dx$$ and $$\int_0^\infty\ln(x)\cos(x^2)dx$$ I believe I have seen these in this forum before, but I cannot find them again using the search function. Can someone help me compute these integrals, or maybe just share the original link? Thank you.


What are the quadratic residues of an odd prime?

I need to prove that -1 is a quadratic residue of an odd prime p iff p = 1 (mod 4)  Any Ideas? Thanks


Complexity of counting the number of triangles of a graph

The trivial approach of counting the number of triangles in a simple graph $G$ of order $n$ is to check for every triple $(x,y,z) \in   {V(G)\choose 3}$ if $x,y,z$ forms a triangle.   This procedure gives us the algorithmic complexity of $O(n^3)$.  It is well known that if $A$ is the adjacency matrix of $G$ then the number of triangles in $G$ is $tr(A^3)/6.$  Since matrix multiplication can  be computed in time $O(n^{2.37})$ it is natural to ask:  Is there any (known) faster method for computing the number of triangles of a graph?


Caching proxy for yum and debian repositories

Does a caching proxy for yum exist, similar to approx for Debian repositories? Is there a way to have reprepro behave the same as approx? I have heard that approx was not as stable; besides, I would prefer the use of reprepro so that I could use my existing web server to serve the repository.


Conjugate subgroup strictly contained in the initial subgroup?

Let $G$ be a group, $H\subseteq G$ a subgroup and $a\in G$ an element of the group. Is it possible that $aHa^{-1} \subset H$, but $aHa^{-1} \neq H$?   If $H$ has finite index or finite order, this is not possible.


I need your opinion about the word order in the following sentence: “In her garden grows a cherry-tree.“? Is it grammatically acceptable?


Why ISNumeric() Transact-SQL function treats some var-chars as Int

SELECT some_column  FROM some_table  WHERE some_column = '3.'   Return row/rows  SELECT some_column  FROM some_table  WHERE ISNUMERIC(some_column) = 0    AND some_column IS NOT NULL    AND some_column <> ''   Does not return any non numeric row/rows. there is a row which has a column value of '3.'  Am i missing something. Please Advise.


Is there any way to put axis environment at specific coordinates? For example if I want the function plot to be a secondary part of a big tikzpicture.  This is a MWE:  \documentclass{standalone} \usepackage{pgfplots} \begin{document} \begin{tikzpicture} \coordinate (coord) at (1,2); \begin{axis}[anchor=(coord)] \draw [blue,fill] (Point) circle (2pt) node [right] {(1,2)} \end{axis} \end{tikzpicture}


Add a list of followed proposal sites which got deleted?

I created some proposals on Area 51, and I (obviously) followed them all. Unfortunately, they all got deleted for not meeting the three-day requirements. Whenever I return to my Area 51 profile the proposals that I followed, but were deleted, are not shown.  So, should we add a list of followed proposal sites in the user's profile which got deleted on Area 51?


Let $f$ and $g$ be entire functions such that $e^f + e^ g=1$ then how to show $f$ and $g$ are constant. I am having trouble in proving these. any help would be appreciated. Thanks in advance.


Achievements tab isn't working in Area 51

When I try to bring down the Achievements tab in Area 51, it's showing an error dialogue.  Strangely enough, the global inbox dropdown works just fine.  Could be connected to .  Screenshot:


What is "state RELATED,ESTABLISHED" in iptables?

2064  871K ACCEPT  all  --  *    *    0.0.0.0/0  0.0.0.0/0  state RELATED,ESTABLISHED  0     0    DROP    tcp  --  *    *    0.0.0.0/0  0.0.0.0/0  tcp flags:0x3F/0x00  0     0    DROP    tcp  --  *    *    0.0.0.0/0  0.0.0.0/0  tcp flags:!0x17/0x02 state NEW  0     0    DROP    tcp  --  *    *    0.0.0.0/0  0.0.0.0/0  tcp flags:0x3F/0x3F  0     0    ACCEPT  all  --  lo   *    0.0.0.0/0  0.0.0.0/0            61    3712 ACCEPT  tcp  --  *    *    0.0.0.0/0  0.0.0.0/0  tcp dpt:80  0     0    ACCEPT  tcp  --  *    *    0.0.0.0/0  0.0.0.0/0  tcp dpt:443  0     0    ACCEPT  tcp  --  *    *    0.0.0.0/0  0.0.0.0/0  tcp dpt:22    I am a little confused by the first line of this:  2064  871K ACCEPT  all  --  *    *    0.0.0.0/0    0.0.0.0/0     state RELATED,ESTABLISHED    What is state RELATED,ESTABLISHED?  I am trying to block access to all but 80,443,22. Am I accomplishing this here?


Can I revert to the Mountain Lion style labels instead of Mavericks tags? How?

I don't like the almost invisible little colored dots (tags) that have replaced the full-length color highlighted labels used in Mountain Lion.  Is there a way to go back to using full-field labels?


Finding the type of algebraic structure formed by the given types of set

Let's say I am given a set that has a bunch of sets as its element, for instance, the power set of natural numbers less than or equal to 1, denoted as $P(1)$. Is it true that such kinds of sets, where the elements are sets, never form a group under a set operation? I am wondering what it means for sets to have inverses?


Do search engines index a rich snippet data from HTML which is not visible?

I want to add some piece of data to rich snippets (for example, breadcrumps), but this information is not visible on the page (for example, because the designer has not yet prepared the sketches)  Is there a way to tell search engines to index this data?


i wonder what does the @Override does in Java? My program runs properly without it. Netbeans put a yellow line in my method suggesting to use @Override. But even if i ignore the suggestion, my program runs without any error. Well, i'm just curious. thanks for any reply.


proof that p implies q entails not p or q

I could easily prove   $\neg P \lor Q$ entails $P \rightarrow Q$.  It is well known that   $P \rightarrow Q$ entails $\neg P \lor Q$  but I couldn't find a way to prove it.   Although there is the same question;  ; it's a little bit confusing and I need to see step by step solution.  Could you show me the way by using Natural Deduction?


Before you read I want you to know that here I'm a layman and I was just wondering.  It is often visualized, how wormhole works using a curved paper like C, and making a short cut through there:    But I don't understand, how this shortcut is made by itself. I mean why spacetime is supposed to be like C in first place?  But I can speculate. If there is a large enough black hole at top of the C, it can make its path through bottom of C, thus making a wormhole? (But probably it would still be a black hole, visible at two sides of spacetime.)


Is 14.04 LTS sufficient for for dual CPUs

I am totally new to UBUNTU (and dual CPUs).  Do I just download the current iso (14.04 LTS 64-bit) from www.ubuntu.com/download/server, or do I need something else to support a server using dual cpus?    I have a Dell PowerEdge R720 server with dual Intel Xeon E5-2637v2 4c 3.5GHz CPUs; with hardware based RAID (PERC H710P); iDRAC7 Express...  We have placed it on the rack and upgraded the BIOS.    I am after the usual LAMP system.


Can a druid Wild Shape into a Cranium Rat and use Telepathy?

One of the limitations of using Wild Shape is that, in most beast forms, a druid cannot talk, as per the PHB:     You can’t cast spells, and your ability to speak or take any action that requires hands is limited to the capabilities of your beast form. (my emphasis)   One of the key benefits of Wild Shape is scouting ahead for the party, and it turns out the Cranium Rat (from Volo's Guide to Monsters) is ideal for this:   Rats are commonplace creature in many towns or dungeons, and are therefore less prone to generate suspicions even if detected. Darkvision is a benefit in dark places. No extra Stealth bonus, but +2 from DEX is still a bonus. Telepathic Shroud makes it immune to emotion-sensing, mind-reading and divination spells.   Many animal shapes have great scouting abilities, but the Cranium Rat even has the ability to use Telepathy for up to 30ft, potentially allowing the druid to communicate secretly with the party, relaying information about what it sees.  I'm still baffled that the Cranium Rat is categorized as a beast, and not as a monster of some kind, but it's a beast per the RAW. Since the Telepathy ability of the Cranium Rat is a "capability of the beast form", does this mean that a druid can indeed use Telepathy when transformed into a Cranium Rat?


Multiplying the residue classes mod n by a coprime

I noticed an interesting result when playing around with mods. If I take all the residue classes of $n$ and multiply each of them by an integer $q$ such that $n$ and $q$ are coprime, then each residue class maps to a unique new residue class. For example, if $n=7$ and $q=3$ then the residue classes ${0,1,2,3,4,5,6}$ get mapped to ${(0\cdot3), (1\cdot3), (2\cdot3),(3\cdot3),(4\cdot3),(5\cdot3),(6\cdot3)}$ which in turn becomes ${0,3,6,2,5,1,4}$. This is simply a permutation of $0,1,2,3,4,5,6$ which are the residue classes we started with. In other words, is there a way to prove that when you multiply $\{0,1,2,\dots, (n-1)\}$ by $q$, no two products will be equivalent mod n?


Do I need a visa on a South-African passport if in transit in Munich en route to St. Petersburg


I have windows 7 already installed and I am trying to install ubunutu using USB installer. I am unable to find available partition , i have read many forums saying i can have only 4 partition , I am attaching the screen shot of the avaialble partition , please help me. I think sd3 is not used since its just 126kb can i format and use that partition? On my windows I have three drives c d and f(which i created for ubuntu but its not shown up while installing) All my drives are shown as Simple Volume.   Is wubi Windows installer safe to try in this case


Is it possible to password protect a zip file created by Windows itself (without external tools?)

I normally use a tool like WinZip, 7Zip, or WinRAR to create zip files but I'm on a Windows 7 system that doesn't have these tools installed (and I can't install new apps).  Outside of 3rd party tools like the above, can I create (or modify) a zip file in Windows 7 and request that it be password protected? (the files would contain sensitive information that I plan to transmit to another PC)*  e.g. the process I'm familiar with on Windows is to select the files, right click and choose: "Send to..." > "Compressed (zipped) folder" - but there doesn't seem to be any additional options.  * Note: I'm aware this isn't 100% secure, locked down mega encryption - just looking for "reasonable effort" to secure the data in transit.


We know as we increase the number of sides in regular polygon, after infinite repetition it will give us a circle. So, is there any way to find a function which approaches to value of $\pi$ when we consider  $\lim\limits_{n\to \infty}$?


How to find out if a Canadian cellphone works abroad?

We already have a  and the Canadian cell-phone marker is equally twisted with most carriers being helpful at telling what technologies and standards they use. As I am about to go to Mexico and would like to bring my Motorola Charm cellphone running on Rogers' network, this is perfect time to found out how to do this homework :)   Given an already-owned cellphone and which runs on an existing network. How does one find out if a phone will work on a specific destination country? How to find out if it will accept a local SIM which would give better rates  than roaming?   For using a local SIM, obviously assume the phone is unlocked. Mine is.


Minimizing $\sum_{i=1}^n \max(|x_i - x|, |y_i - y|)$ - Sum of Max of Absolute Values

Suppose there are $n$ points $(x_i, y_i)$ for $i = 1,\ldots,n$. Please find another point $(x, y)$ to minimize function: $$\sum_{i=1}^n \max(|x_i - x|, |y_i - y|)$$


How can I produce exercises in one part of a LaTeX document with selected answers in another? I could, of course, simply typeset the questions and the answers separately, but this is too likely lead to divergence in the labels for the questions and the answers as the document is edited.   What I'd really like is a command that would allow me to typeset exercises at the point at which the command was used and which took an optional argument for a solution to be stored until a final section (chapter, or part) "Selected Exercise Answers". I'd like the questions (and the selected answers) to be labeled in the output by Chapter.Section.Question or even Chapter.Question.


I've written a simple program to check if the input is the letter O or not.  For some reason, even when I type the letter O, the program outputs that the input is not the letter O.  I have used the Eclipse debugger to ensure that the input variable actually equals "O".  import java.util.Scanner;  public class scannerTest {  public static void main(String[] args) {     Scanner scan = new Scanner(System.in);     System.out.println("Give your input. I will tell you if your input is 'O' or not");     String input = scan.next();     if (input == "O"){         System.out.println("Your input was 'O'");         }     else {         System.out.println("Your input was not 'O'");     } }  }


A function that grows faster than any function in the sequence $e^x, e^{e^x}, e^{e^{e^x}}$...

Is there a continuous function constructed by elementary functions, or by integral formula involved only elementary functions (like Gamma function) that grows faster than any $e^{e^{e...^x}}$ ($e$ appears $n$ times)?  I ask for the answer with a single formula. Gluing continuous function together is too trivial.  The function need not to be defined on whole $\mathbb{R}$, the domain $(a, \infty)$ is acceptable.


Just use WSFC without Always On Failover Cluster Instance?

There was some unanswered questions about the difference between "Windows Server Failover Clustering" and "Always On Failover Cluster Instance".   From MS document:  A Windows Server Failover Clustering (WSFC) cluster is a group of independent servers that work together to increase the availability of applications and services. SQL Server 2017 takes advantage of WSFC services and capabilities to support Always On availability groups and SQL Server Failover Cluster Instances.   So we have 3 terms   Windows Server Failover Clustering Always On availability groups SQL Server Failover Cluster Instances   Does that mean i have to combine 1 with 2 or 3? Or i can only use 1 only?  Because in my case (2 EC2 instance with SQL Server 2016 Standard), here's what i did   On first EC2, i installed Failover Clustering Manager role from Server Manager Then i created cluster and add nodes I did some other configurations including DNS, network, witness Now when one node go off (by stop EC2), the other node go online  In SQL Management, i just configured Merge Replication between 2 SQL Server insides 2 EC2   In this case, i used only WSFC? The reason why i asked is because in FCI document, it stated:  Storage Contrary to the availability group, an FCI must use shared storage between all nodes of the FCI for database and log storage. The shared storage can be in the form of WSFC cluster disks, disks on a SAN, Storage Spaces Direct (S2D), or file shares on an SMB. This way, all nodes in the FCI have the same view of instance data whenever a failover occurs. This does mean, however, that the shared storage has the potential of being the single point of failure, and FCI depends on the underlying storage solution to ensure data protection.   But i noticed that i didn't have any shared storage.  @The "Are “Always On Failover Cluster Instances” and “SQL Server Failover Clustering” the same thing?" didn't explain it.


Would you please throw a light on "with whom VS. with who"?

Would you show me if they mean the same thing? or, which one is incorrect?   A. Whom did you go with?  B. Who did you go with?


Range of A and null space of the transpose of A

So I'm complete stuck with something. I know it the following statements are true (or at least the seem to be from the results that I got from messing around with it a bit on MATLAB), but I don't understand why they are true or how to show so. Let $A$ be and $m$X$n$ matrix. Show that:  a) if $x \in N(A^TA)$ then $Ax$ is in both $R(A)$ and $N(A^T)$.   For this one I messed around with it with my own examples and I got $Ax=0$, therefore satisfing the statement, but I don't understand what's actually going on.   b) $N(A^TA)=N(A)$  again, makes sense when I see the results in MATLAB, but don't undestand why it works.  c) $A$ and $A^TA$ have the same rank  d) If $A$ has linearly independent columns, the $A^TA$ is nonsingular.  For the last two I have no idea on how to even start showing the relationship. I feel like I'm missing some crucial relationship between $A$ and $A^TA$, but I'm just not seeing it.   I would greatly appreciate any help of sugestions on how to show that these statements are true.   Thank you very much.


I am trying to write a simple equation: G=log(base 2) (R)  but when I write this in latex:  \begin{equation} \cal{G} = \log_{2}(\cal{R}) \end{equation}   the number 2 becomes a symbol:    Any ideas?


What is nonce and how to use it with Ajax in WordPress?

I am trying to learn, how to use Ajax in WordPress with proper way. This is what I learned:  Step 1: Create Ajax file and register it using wp_enqueue_script.  function wpdocs_theme_name_scripts() {     wp_enqueue_script( 'script-name', get_stylesheet_directory_uri() . '/js/ajxfile.js', array(), '1.0.0', true ); } add_action( 'wp_enqueue_scripts', 'wpdocs_theme_name_scripts' );   Step 2: Use ajax Like this in ajxfile.js:   $( document ).ready(function() {  $('#id').on('click',function (e){            alert("Its Working");     var up = 1;     var id = $( "#id" ).data( "user_id" );     $.ajax({             type: "POST",                 url: "runcode.php",                 data: {up:up, id:id},                 success:                     function(result){                 alert("result");                         }         }); });  });   STEP 3: adding HTML in page:        <a href="#" id="id" data-user_id="<?php echo $user_id = get_current_user_id(); ?>"    data-post_id="<?php echo $post_id = get_the_ID(); ?>">                Every time someone click on the link Its successfully alert "Its working" statement. Now I want to retrieve that data and want to add it in user meta. But its confusing me. And whats that nonce thing is? Can anyone guide me to right direction?


ConcurrentModificationException thrown without directly looping through collection

I have the following code:  // Creates ArrayList with integers 0-9 ArrayList<Integer> intKeys = new ArrayList<Integer>(); for (int x = 0; x < 10; x++) {     intKeys.add(x); }  // Creates iterator with integers 0-9 Iterator<Integer> allKeys = intKeys.iterator();  // Loops 10 times, each time obtaining a key to remove from the ArrayList for (int x = 0; x < 10; x++) {     Integer key = allKeys.next();     intKeys.remove(key); }   I understand that ConcurrentModificationException is thrown if an element of a collection is removed while the collection is being looped over, such as:  for (String key : someCollection) {     someCollection.remove(key);     }   but right now I'm looping over nothing - just an arbitrary number of times. Furthermore, the error line is interestingly Integer key = allKeys.next(); What could be the cause of this exception?


How to copy complete content on terminal to a text file using commands ?(Not for one output but everything on terminal)

How to copy complete content on terminal to a text file using commands .


Integrable random variable X such that X^2 is not integrable

can anyone  help me? I have to show an example of an integrable random variable X such that X^2 is not integrable (it is not specified discrete or continuos case) I know that a r.v. is integrable if and only if its expected value is well-defined  and is said to be square integrable if the expected value of its square exists and it is well-defined. But I have not idea what type of random variable respects as I requested. Thank you in advance


The omission of "should" in a clause sentence

I would like to ask if the sentence below is grammatically correct. If yes, could anyone that is familiar with this rule of usage explain how to use it and cover the complete usage?      It's a matter of urgency that the plan be implemented.   As can be seen from this sentence, the word "should" is omitted. As far as I learned about the usage of should, it's omitted when it's used with some verbs such as advise, suggest, command etc.   Thanks in advance.


Prove that a Linear Transformation is Normal, such that $T^2=T$

Let V be a finite  inner product space and $T:V\rightarrow V$ a linear transformation such that $$T^2=\frac{1}{2}(T+T^*)$$.      Prove that         $T$ is a "Normal Transformation", such that $$TT^*=T^*T$$   $T^2=T$      Proving the first statement isn't hard and I did it that way:  $T^*=2T^2-T$ $\Rightarrow TT^*=T(2T^2-T)=(2T^2-T)T=T^*T$  Therefore,  $TT^*=T^*T$.  However, proving the second statement was much harder, and I couldn't figure it out.  Thanks,  Alan


How to dynamically add email addresses to  tags from block of text using regex

I previously asked a similar question but want to be more clear about the current behavior and the desired behavior. I want to make a function which takes a block of text that contains normal text, email addresses, and URL's, then converts all URL's and emails into  tags. It then displays this converted text in a
 tag on the page where the email and URL are clickable links. Input example: Hello please email me at name@email.com my other email is example@example.com thank you  Expected Output: Hello please email me at name@email.com my other email is example@example.com thank you  Currently I have a function which takes in an array of strings and checks if each string contains a URL, email, or text, then uses document.getElementById("content").innerHTML to append it to the DOM. The problem is when I add an email address, the  tags overlap and I have no idea why. Current output: Hello please email me at mailto:name@email.com my other email is example@example.com thank you.   As you can see the  tag overlaps with the existing href and I have absolutely no idea why.   var inputTextArray = ["Hello", "please", "email", "me", "at", "name@email.com", "my", "other", "email", "is", "example@example.com", "thank", "you"] var emailTest = /(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))/;  inputTextArray.forEach(function(inputText) {   var newItem = inputText.replace(/[\n\r]/g, ' ') //removes newline characters   if (newItem.includes("http://") ||     newItem.includes("https://") ||     newItem.includes("ftp://") ||     newItem.includes("www.")) {     //URLs starting with http://, https://, or ftp://         var exp = /(\b(https?|ftp|file):\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])/ig;     var text1 = newItem.replace(exp, "$1");     var exp2 = /(^|[^\/])(www\.[\S]+(\b|$))/gim;     document.getElementById("content").innerHTML += ' ' + text1.replace(exp2, '$1$2') + ' ';   } else if (emailTest.test(newItem)) {     //push in emails     var  email  =  ""  + newItem +  ""     document.getElementById("content").innerHTML += ' ' + email;   } else {     //push in non url string     document.getElementById("content").innerHTML += ' ' + newItem;   } })    The first if statement to convert URLs to  tags works great and I was wondering if any one has a similar solution for emails using RegEx? Or how the above code can be fixed? Thanks in advance.


Working with frequently changing requirements

How Software Testing Engineer should act in environment where requirements are very frequently changing? Big tasks appear suddenly so tester doesn't perform them in a proper way. Developers do what wasn't expected and stories are done just before demo. How processes are usually fixed?


Proving that if $\langle Ax,x\rangle =0$ for every $x$, then $A$ is the zero operator

I feel kind of dumb but I needed this little claim as a part of a proof I'm writing, and I figured out that I'd better just ask, since I could not find the correct algebraic manipulation needed in order to prove it.  So I want to prove this: Suppose $H$ is an Hilbert space, and $A: H\to H$ is a linear operator (if that matters, which I believe it does not, we can assume that $A$ is a projection). Suppose that for every $x\in H$, $(Ax,x)=0$. Then $A=0$.  What I tried to do is a little bit of Cauchy-Schwarz and some algebra but nothing worked out.  Thanks!


I am studying the command  in the post about How to compile and install Qt, qwt and overclock the RPI  sudo mount -o loop,offset=62914560 <date>-wheezy-raspbian.img /mnt/rasp-pi-rootfs   I do fdisk 2016-02-26-raspbian-jessie.img and I get  Disk: 2016-02-26-raspbian-jessie.img    geometry: 976/128/63 [7870464 sectors]   Signature: 0xAA55        Starting       Ending    #: id  cyl  hd sec -  cyl  hd sec [     start -       size]   ------------------------------------------------------------------------    1: 0C    0 130   3 -    8  40  32 [      8192 -     122880] Win95 FAT32L    2: 83    8  40  33 -  489 232  63 [    131072 -    7739392] Linux files*    3: 00    0   0   0 -    0   0   0 [         0 -          0] unused          4: 00    0   0   0 -    0   0   0 [         0 -          0] unused            Why is offset specific in mount?


I have a very short question.  Is $AA^T$ positive semidefinite, i.e. $x^T AA^Tx\geqslant 0$ for suitable $x$?


Set search navigation to inherit from parent site with CSOM

I am working on a solution in SharePoint Online where I want to accomplish the following using CSOM:   Set all subsites to inherit search navigation from parent. To achieve this I have  this little code-snippet which actually works and sets a property on a subsite web to inherit parent search navigation.          using (ClientContext context = new ClientContext("ParentSiteURL"))         {         context.Credentials = new SharePointOnlineCredentials(struser, password);         Web web = context.Site.OpenWeb("SubsiteName");         var allProperties = web.AllProperties;         context.Load(allProperties);         web.AllProperties["SRCH_VERT_SET_WEB"] = "{\"Inherit\":true}";         web.Update();                         context.ExecuteQuery();         }    However, even though the property is updated and search settings are now set to inherit parent navigation - it's not working.  I need to navigate to "Site settings > Search settings" and click OK for it actually work. So it seems like I am missing an Update of some kind...  Any help would be much appreciated.


I have a problem about using Facebook. However, I cannot find a suitable site on Stack Exchange to ask it on. What site should I use?


Storing API keys in salesforce to callout to custom service

We have our own app in Salesforce.When a customer service agent (non-privileged user) initiates/completes a task, we need to let our other systems know (via message bus) to do other things.  Now, the easy part is storing the key in a secure encrypted config field. The confusing part is having these customer agent's workflows be able to use the field and post out to our external service. The obvious solution is to enable the agent's profile to read encrypted data, but I feel like that defeats the purpose of obscuring/hiding API keys from everyone else, other than admin devops like myself.  How have other people worked around this?


Is this a good scenario for MSSQL CASE statement?

I'm trying to offload some work from the CF server to the SQL Server (2008).  I'm running a query and the statusID value that is returned corresponds to one of 4 colors (Green, Yellow, Orange, and Red).  select id, statusID  from table   If this is the ideal situation to use a case statement, is this correct?    select id,       case           when statusid in (1,20,24)               then 'red'     END as xxxx) as yyyy, * from TABLE   And if this is correct, what goes into xxxx and yyyy above?


How do I name each desktop within the Windows 10 Taskview?  If I click the Taskview button on the Taskbar  then the view zooms out from the current desktop.  A top bar shows the available desktops. I have two Taskview desktops named Desktop 1 and Desktop 2.  I would like useful names for the desktops; e.g. Gaming, or Project ABC, or Work, etcetera.


I know once you have purchased a home you can leave items in the chests inside for easy storage.  My question is regarding the surrounding tables and shelves - if I remember correctly from Oblivion you could leave items on the tables and shelves and they would remain. I'm planning on trying this with a not "super needed" item and seeing if it disappears but I just wanted to ask the community if they have tried this and what the results were.


Creating a switch between USB and USB OTG for phones

I'm trying to create a charger that knows how to switch between OTG and charging mode. The OTG side is working, and my Samsung S4 goes into charging mode. However, charging is really slow. It even loses charge, even with the charging indicator on.  There are two things that do concern me about the schematic I came up with:   A diode is used on the Vbus line, causing my 5V supply to become a 4.3V supply I did not follow the S4 charging specification   Some things I looked up due to the current situation:   Samsung S4 charging schematic:  Maxim's "Charging Batteries Using USB Power":      I modified my circuit a little bit, so that my attachment does not need to worry with the charging specifications of different devices.  Would it work if I:   Used a switching regulator to raise the voltage up from 4.3v to 5.0v rated for 1.5A, and Used a USB multiplexer so that my circuit can support different charging specifications, while still fully functional for USB-OTG devices?    I have attached a schematic for reference:   The chips I used were:   USB Multiplexer:  Switching Regulator 5V1.5A:  Solid State Relay: $file/CPC1017N.pdf   Also, what's the advantage of using a voltage divider instead of just limiting voltage with a single resistor?


Suppose that $f_k$ is a sequence of differentiable functions that converges uniformly to a function $f$. Must $f$ be differentiable?

Suppose that $f_k: (0,1) \rightarrow \mathbb{R}$ is a sequence of differentiable functions that converges uniformly to a function $f: (0,1) \rightarrow \mathbb{R}$. Must $f$ be differentiable?  So I'm pretty sure this isn't true but struggling to find a simple counterexample.


ephemeral-ephemeral ECDH and MITM attack

ephemeral-ephemeral ECDH is it susceptible to MITM attack ? if yes, can you please give me a detailed answer ( Workflow that can be followed by the attacker) and how we can prevent this attack (static-ephemeral or we can keep ephemeral-ephemeral and change some parameters)?  Thank you in advance


Find the integral $\int_{0}^\infty \frac {1}{(x^2+1)(x^7+1)} \, dx$

How i should deal with it, i’ve tried fraction decomposition, but haven’t worked so far. $$\lim_{n\to \infty} \int_{\frac 1n}^n \frac {1}{(x^2+1)(x^7+1)} \, dx$$


Transit visa for France while traveling to Fiji?

I am travelling to Fiji from the USA.  I have a layover of 12 hrs in Paris.  Will I require transit visa for the stop in Paris?  I will not leave the airport.  I am a Fijian Citizen.


I am trouble proving $P(a\cap b)\ge P(a)+P(b)-1$  $P(a \cup b)=P(a)+P(b)-P(a \cap b) $  so  $P( a \cap b)= P(a)+P(b)-P(a \cup b)$  I am not a student.


There's a question in American English:     Who has an extra ticket?   How to answer more correctly:     That guy has.   or      That guy does.


Connection string to ms-access database not correct in deployed PHP site

I have successfully made a connection to my access database on my local computer but when I upload my config.php file which contains the connection string on my web server and when the insert command runs it displays a blank page without making entries to the database.   $conn = new COM ("ADODB.Connection")   or die("Cannot start ADO");   $connStr = "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=/onlineadmission.mdb;Jet OLEDB:Database Password=;";   $conn->open($connStr);   It works well on my local computer but not when uploaded. Where is the problem?


convergence of $ \sum_{k=1}^\infty \sin^2(\frac 1 k)$   How can I do this? Should I use the Ratio Test (I tried this but it started getting complicated so I stopped)? Or the Comparison test(what should I compare it to?)?


How can I toggle the automatic dock hiding feature programmatically?  To be more precise, how can I toggle the feature from a command line script or toggle it with a shortcut?


For every $n\ge3$ there exists $n$ different integers $a_1,...,a_n$ so that $\frac{1}{a_1}+\frac{1}{a_2}+...+\frac{1}{a_n}=1$

I have a hard induction problem here that I feel completly lost on.  For every $n\ge3$ there is n different positive integer $a_1,...,a_n$ so that $\frac{1}{a_1}+\frac{1}{a_2}+...+\frac{1}{a_n}=1$.  There is only one possible solution for $n=3 $  $\frac{1}{2}+\frac{1}{3}+\frac{1}{6}=1$  for $n=4$ there is 2 possible solutions and they both start with $\frac{1}{2}$.  $\frac{1}{2}+\frac{1}{3}+\frac{1}{8}+\frac{1}{24}$ and $\frac{1}{2}+\frac{1}{4}+\frac{1}{5}+\frac{1}{20}$.  I think the first one is the one.  For $n=5$ there is alot of different possible solutions but it have to start with at least $\frac 13$  I think it have to start with $\frac 12+\frac13$ and then be some kind of sum answer for the last $\frac16$ based on $n$. But I don't know  I have tried finding a pattern but not getting anywhere anymore. Any tips on how to tackle a problem like this?


I am doing past exam papers preparing for the finals and I came across this questions about three times:  Prove that:  $$\frac{a_{1}+a_{2}+\cdots+a_{n}}{n}\geq \sqrt[n]{a_{1}.a_{2}...a_{n}}$$ Different papers require different approaches to proving it but most of them use induction. Can someone please explain to me how to prove it using induction? I can do the first steps but get stuck at proving that:  $$\frac{a_{1}+a_{2}+\cdots+a_{k}+a_{k+1}}{k+1}\geq \left ( \frac{a_{1}+a_{2}+\cdots+a_{k}}{k} \right )^{\frac{1}{k+1}}\left ( a_{k+1} \right )^{\frac{1}{k+1}}$$


Does anyone know any example that invalidates the following affirmation:     If a morphism $f:A\to A$ induces the identity $\hat f:\operatorname{Spec} \left( A \right) \to \operatorname{Spec} \left( A \right)$ then $f = \operatorname{id} _A $.


Bluetooth vs Wifi. Which one has more bandwidth?

I've been reading articles like this   I uses bluetooth to access my omni 10 harman kardon speaker. I am very disappointed with the result. The sound from bluetooth is choppy.  I wonder if it is because bluetooth has much lower bandwidth than wifi.  The problem is, while the harman kardon speaker can handle wifi, they do not have any software that allows my PC to stream sound to them directly.  So any specs? Does wifi has bigger bandwidth? Should I switch to speakers that can transmit sounds via wifi?


How many square numbers exist that have the length $N$ in the decimal system?  E.g. for the length $N=1$ there exist 4 square numbers (0, 1, 4, 9).  Thank you


How can a Word writer write a manuscript with a LaTeX writer?

What software or tutorials are there that allow Word writers to write with LaTeX writers without Word writers having to learn LaTeX


I would like to plot circle (or another curve) with positive direction (and show it wit arrows).  This plots the circle  \documentclass{article} \usepackage{tikz} \RequirePackage{pgfplots} \usetikzlibrary{shadows} \usetikzlibrary{shapes} \usetikzlibrary{decorations} \usepackage{verbatim} \usepackage[active,tightpage]{preview} \PreviewEnvironment{tikzpicture} \setlength\PreviewBorder{5pt} \begin{document} \begin{tikzpicture}     \begin{axis}[             xmin=-1.5,xmax=2.5,ymin=-1.5,ymax=1.5,             axis lines=center,             ticks=none,             unit vector ratio*=1 1 1,            ]                   \addplot [very thick, smooth, domain=(0:2*pi)] ({1.+cos(deg(x))},{sin(deg(x))});        \addplot[only marks,mark=*] coordinates{(1,0)};         \end{axis} \end{tikzpicture} \end{document}   And I want to add arrows like that    Would you advise me how to add such arrows?


How to compare two TeX codes and mark differences with color

I would like to find easy tool, which compares two TeX codes and generates a PDF file of the first code, in which the differences from the second code are marked by a given color. I use winedt 7.0 under windows 7.  I just noticed that latexdiff provides what I need. As far as I understand it is included in Miktex. Is there an interface (menu commands) in winedt 7.0, which allow to work with latexdiff ?


How to calculate overlap between empirical probability densities?

I'm looking for a method to calculate the area of overlap between two kernel density estimates in R, as a measure of similarity between two samples. To clarify, in the following example, I would need to quantify the area of the purplish overlapping region:  library(ggplot2) set.seed(1234) d <- data.frame(variable=c(rep("a", 50), rep("b", 30)), value=c(rnorm(50), runif(30, 0, 3))) ggplot(d, aes(value, fill=variable)) + geom_density(alpha=.4, color=NA)     A similar question was discussed , the difference being that I need to do this for arbitrary empirical data rather than predefined normal distributions. The overlap package addresses this question, but apparently only for timestamp data, which doesn't work for me. The Bray-Curtis index (as implemented in vegan package's vegdist(method="bray") function) also seems relevant but again for somewhat different data.  I'm interested in both the theoretical approach and the R functions I might employ to implement it.


I am refactoring some code for several enum collections that support the [Flags] attribute.  I am trying to come up with a generic class that allows for common methods (adding, removing and checking enums exist in the collection etc).  I began with this code:  public class EnumFlags<T> {     protected T collection;      public void Add(T value)     {         this.collection = this.collection | value;     } }   However, I cannot use the | operator on type T.  I cannot add a constraint for T to be an enum (where T : Enum is not allowed).  Any ideas to approaching this problem?


I want to statically initialize a map<string, pair<some_enum, string> >. Let's say a map from employee id to job title (enum) + name.  I would love for it to look like this:  map<string, pair<some_enum, string> > = {   { "1234a", { BOSS, "Alice" }},   { "5678b", { SLAVE, "Bob" }},   { "1111b", { IT_GUY, "Cathy" }}, };   What is the best way to do this in C++?


Subject predicate inversion due to negation

I was  subject predicate inversion     inverted word-order... is also used in clauses introduced by a   negative or restrictive clause element. In the following example, the   initial element Not only is negative and is followed by inverted word   order: could congress declare...      (12) Not only could (v) Congress (S) declare (V) war but the states   were forbidden to engage in it without the consent of Congress.   I am struggling to intuitively apply this.  Can someone explain the rule? E.g. the former sounds wrong, but perhaps the latter inversion does less damage. Maybe not.  Is the sentence Not all my cigs lit a candidate for inversion in the first place? And why or why not?   Not all my cigs lit -> Not all my lit cigs Not all my cigs lit burning straight -> Not all my lit cigs burning straight   Specifically could the phrase in bold be such an inversion (please ignore whether it is):   Not all your light tongues talking aloud / could be profound


Did Darth Vader really turn to the light side?

Vader’s goal was to rule the galaxy. The emperor stood in his way. He killed the emperor. How does that qualify him as turning to the light side? Because he declares he is now on the light side?  He kills thousands of innocent Padawans, unknown number of other beings. Utters one sentence about turning to light side and it’s all good? Pretty sketchy.


i just have a problem on ubuntu. when i go to ubuntu Software Center, i can not download any application although i can surf the internet. when i download an app it stops at 10% and then an message appears <1. please help. i am from greece and my computer does not support ubuntu 14,04+.


Convergence of the series $\sum \limits_{n=2}^{\infty} \frac{1}{n\log^s n}$

We all know that $\displaystyle \sum_{n=1}^{\infty} \frac{1}{n^s}$ converges for $s>1$ and diverges for $s \leq 1$ (Assume $s \in \mathbb{R}$).  I was curious to see till what extent I can push the denominator so that it will still diverges.  So I took $\displaystyle \sum_{n=2}^{\infty} \frac{1}{n\log n}$ and found that it still diverges. (This can be checked by using the well known test that if we have a monotone decreasing sequence, then $\displaystyle \sum_{n=2}^{\infty} a_n$ converges iff $\displaystyle \sum_{n=2}^{\infty} 2^na_{2^n}$ converges).  No surprises here. I expected it to diverge since $\log n$ grows slowly than any power of $n$.   However, when I take $\displaystyle \sum_{n=2}^{\infty} \frac{1}{n(\log n)^s}$, I find that it converges $\forall s>1$.  (By the same argument as previous).   This doesn't make sense to me though.   If this were to converge, then I should be able to find a $s_1 > 1$ such that  $\displaystyle \sum_{n=2}^{\infty} \frac{1}{n^{s_1}}$ is greater than $\displaystyle \sum_{n=2}^{\infty} \frac{1}{n (\log n)^s}$  Doesn't this mean that in some sense $\log n$ grows faster than a power of $n$?   (or)  How should I make sense of (or) interpret this result?  (I am assuming that my convergence and divergence conclusions are right).


What should I do to leave Chile when I've overstayed my visa?

On 15 May, I entered Chile; my visa was for 3 months. On 10 July, I booked a ticket to go to New Zealand. I bought the ticket from LATAM Airlines for $1700 (USD).  But they didn’t let me board the flight to go to New Zealand and also they didn’t refund my money. Now, it is three months that I have been trying to get back my money, but they don’t want to give it to me unfortunately.  Now I want to leave Chile and go back to Amsterdam, my home. What should I do ?


Split-like environment inside cases environment

I'd like to have a cases environment with some cases that are too long to fit on one line. I tried this:  \begin{cases}   \begin{split}     long expression \\ second line of long expression   \end{split} & condition \\   ...   but I get the warning     Package amsmath Warning: Cannot use 'split' here;   trying to recover with 'aligned' on input line 201.   It automatically replaces the split with an aligned environment, which looks like this:    Is there any way to get these long expressions to behave like they were in split or multline environments, with the top line flush left and the next line indented a little?


Visitor automagically transported to Original Question: Status by design or fluke?

If someone visits a question without an answer, that is closed as a duplicate, the person will automatically be sent to the original question. Consequently, it will be impossible to view the contents of the newer question. However, if the newer question received one or more answers posted before being closed as a duplicate,  the page and the answer(s) posted will be visible.  For example, when I am logged out, I cannot see the following question:         Instead, the system directs me automatically to the “original” question      The same situation is repeated when visitors and logged-out users click on the question:       they will be transported to        and its single answer.   On the other hand,  a question which has been closed as a duplicate of two older questions, for instance   will not automagically redirect the visitor  (or the logged-out user) to the older posts.   I checked to see if this was by design in the FAQ   The most relevant piece of information that I could glean was      Should duplicates be deleted?   In general, no: most duplicates stay around. Having multiple copies of the same question with different wording is useful as search fodder, because people looking for an answer may use different wording too.   I also searched  but found nothing which suggests a question that is closed as a duplicate appears "invisible" to visitors or users who are logged out of the site.   I tagged the question as a bug because it's unclear whether this feature is by design or not. If it is, I'm not terribly convinced it's a good idea. Not sure why a new question, which has been carefully composed and upvoted should not be useful to visitors.


unix utility to merge files without space overhead (cat *.txt > merged.txt;rm *.txt in one step)

Is there a utility that dumps a file line by line to stdout and deletes those lines?  I have a number of large files that I want to merge via cat. Of course I could do   cat *.txt > merged.txt    But this will take double the space originally occupied by the txt files. Deleting them after cat like so  cat *.txt > merged.txt && rm -rf *.txt   reduces the storage requirements but still needs 2x the space to be present in the meantime  I'm looking for a command that would stream lines to stdout while at the same time deleting them in the original files:  <some command> *.txt > merged.txt   such that the total space used by *.txt + merged.txt and is never more that what *.txt needed originally


I am using UBUNTU 16.04. My wifi keep disconnecting again and again!! The output of lspci -knn | grep Net -A2 is:  06:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter [10ec:b723] DeviceName:   Subsystem: Hewlett-Packard Company RTL8723BE PCIe Wireless Network Adapter [103c:2231]   Output of lsusb is:  Bus 002 Device 003: ID 0bda:b001 Realtek Semiconductor Corp.  Bus 002 Device 002: ID 0438:7900 Advanced Micro Devices, Inc.  Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 004: ID 064e:c341 Suyin Corp.  Bus 001 Device 003: ID 138a:0050 Validity Sensors, Inc. Swipe Fingerprint Sensor Bus 001 Device 002: ID 0438:7900 Advanced Micro Devices, Inc.  Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub   Output of lspci is:  00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1566 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Mullins [Radeon R4/R5 Graphics] (rev 05) 00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Kabini HDMI/DP Audio 00:02.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 156b 00:02.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 00:02.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 00:02.3 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 00:02.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 16h Processor Functions 5:1 00:08.0 Encryption controller: Advanced Micro Devices, Inc. [AMD] Device 1537 00:10.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB XHCI Controller (rev 11) 00:11.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [AHCI mode] 00:12.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 39) 00:13.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 39) 00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 42) 00:14.2 Audio device: Advanced Micro Devices, Inc. [AMD] FCH Azalia Controller (rev 02) 00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 11) 00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1580 00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1581 00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1582 00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1583 00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1584 00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Device 1585 01:00.0 Display controller: Advanced Micro Devices, Inc. [AMD/ATI] Jet XT [Radeon R5 M240] (rev ff) 02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 10) 06:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter 07:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5227 PCI Express Card Reader (rev 01)   Output of dmesg | grep -i firmware is:  [    0.326620] [Firmware Bug]: ACPI: BIOS _OSI(Linux) query ignored [    0.894754] [Firmware Bug]: ACPI: No _BQC method, cannot determine initial brightness [    0.896423] [Firmware Bug]: ACPI: No _BQC method, cannot determine initial brightness [    0.905790] acpi PNP0A08:00: [Firmware Info]: MMCONFIG for domain 0000 [bus 00-3f] only partially covers this bridge [    1.940849] [Firmware Bug]: ACPI: No _BQC method, cannot determine initial brightness [    1.940874] [Firmware Bug]: ACPI: No _BQC method, cannot determine initial brightness [    2.074380] [drm] Found VCE firmware/feedback version 40.2.2 / 15! [   10.624914] rtl8723be: Using firmware rtlwifi/rtl8723befw.bin


What should I do to make it to a top-ranked graduate program given my current situation?

I am from an elite non-IIT school in India (one of BITS Pilani/IIIT Hyderabad/NSIT/DTU). I've just finished my third year, and after taking courses from AI and ML related fields, I realized I am actually interested in the field, and would like to get deeper into one of the subareas of applied ML. I have also identified the professors I would like to work with.   However, there's a caveat; I have a 7 point CGPA (on a scale of 10), mostly because of my youthful immaturity during the initial years of my undergraduate education. I realize that this might not be an ideal justification to bad grades, but this unfortunately is the truth. I also realize that this might very well be a red-flag on my admission to a prestigious PhD program.  I have been working on some projects on my topic of interest, hoping to cover up my grades with some project experience, though none them have produced publishable results yet. Have I totally blew my chances of getting into a top-ranked PhD program? Is there any way I can still fix my chances of getting a good PhD admit?  PS: My current project advisor is not so well-known a researcher that his recommendation will get me through a highly selective admission committee.


I don't understand what it means to "Sell" stock that you don't already own, can someone explain the intuition behind it?

I started a couple months ago to learn more about the stock market and financial education in general, but this particular concept was hard to wrap my head around.  I understand there are bears and bulls behaviors in the stock market, but when I go and sell a stock, how can I sell it if I don't own any of that stock already?  I can understand if I go around the block, find someone selling shoes for 10$, I buy them, then I go two blocks down the street and find someone wanting shoes for 12$, I can make a profit by Selling to him.  But if I reach the guy that wants shoes, how can I "Sell" something I don't own yet?


Suppose $U \subseteq R^3$ is the subset that all three coordinates are positive. Let $D$ be the distribution on $U$ spanned by two vector fields:    $X = y\frac{\partial }{\partial z}-z\frac{\partial }{\partial y}$ , $Y=z\frac{\partial }{\partial x}-x\frac{\partial }{\partial z}$.    Then how to find the integral submanifold?    I had shown that $[X, Y]_p = \frac{y(p)}{z(p)}Y_p+\frac{x(p)}{z(p)}X_p$, hence $D$ is involutive. I also know how to calculate the integral curve of $X$ and $Y$. But I dont know how to proceed to calculate the integral submanifold specifically.


Appendix issues while adding in thesis in lyx document

I am trying to add appendix at the end of  my thesis after references in LyX, Document-> Start appendix here But I am not getting where I am doing wrong as it doesn't come in TOC, please guide me what should I do??   \appendix \noindent \begin{center} \textbf{Questionnaire (Case Study 1)} \par\end{center}


Javascript function differences, is there any?

When I run a function in js it seems to work fine but will this be fine?  function myfunction(){ }  VS  var myfunction = function(){ }  Because both are called the same so does it make no difference? Sorry new to js so i'm just making sure it's good to learn this style. (The first function is what i'd prefer to use.)


Whenever I try editing a file such as test.java with gedit it always gives me this error.  Unable to init server: Could not connect: Connection refused  (gedit:2652): Gtk-WARNING **: 08:19:10.568: cannot open display:   I have looked at other cases when gedit does not open the display but I am not skilled enough to understand what exactly people are doing since it isn't exactly the same error.  What can I do to fix this?


I am working on a project and i want to slim it down a litle so please help me with the following. I have a document structure like this:  /DocumentRoot  |-main.tex  |-title.tex  |  |-/chapter-1  |  |-/images  |  |-chapter-1.tex  |  |-/chapter-2     |-/images     |-chapter-2.tex   My document is like this:  \begin{document} \include{./title} \include{./chapter-1/chapter-1} \include{./chapter-2/chapter-2} \include{./chapter-3/chapter-3} \end{document}   in my chapters i use both some images and some heavy tikz plots so i use externalize and  draft options for quicker compilation. But i want the images to be placed in the respective chapter folders but for example in chapter 3 this works:  \includegraphics[width=\linewidth]{./chapter-3/images/img.jpg}   and this doesn't  \includegraphics[width=\linewidth]{./images/img.jpg}   for some reason xelatex has problems with the relative paths of included chapters. I also want to control the location output and the naming of the externalized tikz documents. Any help with that? I am working with miktex and texworks.