Not able to install VLC and other programs due to strange dependency problems

The following packages have unmet dependencies:  vlc : Depends: vlc-nox (= 2.1.4+git20150226+r54594+19+11~ubuntu14.04.1) but it is not going to be installed        Depends: libsdl-image1.2 (>= 1.2.10) but it is not installable        Depends: libtar0 but it is not installable        Depends: libva-x11-1 (> 1.3.0~) but 1.0.15-4 is to be installed        Depends: libva1 (> 1.3.0~) but 1.0.15-4 is to be installed        Depends: libvlccore7 (>= 2.1.0) but it is not going to be installed        Recommends: vlc-plugin-notify (= 2.1.4+git20150226+r54594+19+11~ubuntu14.04.1) but it is not going to be installed        Recommends: vlc-plugin-pulse (= 2.1.4+git20150226+r54594+19+11~ubuntu14.04.1) but it is not going to be installed E: Unable to correct problems, you have held broken packages.  I tried  sudo apt-get install -f sudo apt-get update sudo apt-get upgrade sudo apt-get purge vlc vlc-nox libsdl-image1.2 libtar0 libva-x11-1 libva1 libvlccore7 vlc-plugin-notify vlc-plugin-pulse   But the error remains. VLC is not the only thing. many other packages I try to install gave me similar dependency errors which I finally gave up installing. I have been using Ubuntu for a while now. I just don't understand why this happens every now and then. Please help ... EDIT: Output of apt-cache policy vlc vlc-nox libsdl-image1.2 libtar0 libva-x11-1 libva1 libvlccore7   vlc:   Installed: (none)   Candidate: 2.1.4+git20150226+r54594+19+11~ubuntu14.04.1   Version table:      2.1.4+git20150226+r54594+19+11~ubuntu14.04.1 0         500 http://ppa.launchpad.net/videolan/stable-daily/ubuntu/ trusty/main i386 Packages vlc-nox:   Installed: (none)   Candidate: 2.1.4+git20150226+r54594+19+11~ubuntu14.04.1   Version table:      2.1.4+git20150226+r54594+19+11~ubuntu14.04.1 0         500 http://ppa.launchpad.net/videolan/stable-daily/ubuntu/ trusty/main i386 Packages libsdl-image1.2:   Installed: (none)   Candidate: (none)   Version table: libtar0:   Installed: (none)   Candidate: (none)   Version table: libva-x11-1:   Installed: (none)   Candidate: (none)   Version table: libva1:   Installed: (none)   Candidate: (none)   Version table: libvlccore7:   Installed: (none)   Candidate: 2.1.4+git20150226+r54594+19+11~ubuntu14.04.1   Version table:      2.1.4+git20150226+r54594+19+11~ubuntu14.04.1 0         500 http://ppa.launchpad.net/videolan/stable-daily/ubuntu/ trusty/main i386 Packages


Asking a question that *must* have been asked before but I can't find

I have a question I'd like to pose on the Stack Overflow site, but I'm sure it's been asked before - I've not seen it before, but it's so fundamentally useful to the specific thing I'm doing (that other people also do) that I can't believe I'm the first to ask it. The problem is I can't find the question for love nor money.  Is there a best practice for asking a question such as this?   (For reference my question is: how to automatically redirect all Python calls to an  virtual environment in Linux). The issue with finding the specific question may be the phrasing I use in the search (I also do a SE search via Google to no avail).


Why is it possible to delete my own post with other's contribution?

I thought that even if for the question writer, it's the most impolite thing to delete own question with other's elaborated answers. Since the question has posted, every participants are able to improve the question via comments, edits, and answers, but who decides to delete one is the writer.  What I want to say is, I think that after someone has posted a question and be helped by others, the question is no longer owned by its original writer.  Why the writer can freely delete her own post?


User friendly list of processing algorithms in the QGIS 3 python console

The QGIS user guide section  has not yet been updated for QGIS 3 and while a  will do the trick with some extra work, it is not as easy and user friendly as the old alglist()  In the user guide the following commands are presented, resulting in a user-friendly list:  import processing processing.alglist()   This still works in the QGIS 2.18.18 python console. Using an algorithm's id one can then use e.g.  processing.alghelp("qgis:dissolve")   to learn about the algorithm's required parameters etc.  Are there any equivalent functions in QGIS 3?  Using something like print([str(e.provider().name()) + ":" + str(e.name()) for e in QgsApplication.processingRegistry().algorithms()]) gets me closer, but still not equivalent in readability to alglist().


How to find $|a|\cdot|b|\cdot|c|$ if $a+\frac 1b=b+\frac 1c=c+\frac 1a$

The question is from the Bangladesh Math Olympiad- Barisal division from $2017$.     $a$, $b$ and $c$ are three separate real numbers, where $a+\frac 1b=b+\frac 1c=c+\frac 1a$. What is the product of the absolute values of $a$, $b$ and $c$?   If they were not different, then $a=b=c \neq 0$ would do it but the real numbers are different so I am confused.    I know that none of $a,b$ and $c$ are equal to $0$.    I can do $a+\frac 1b=b+\frac 1a$ by letting $a=-\frac 1b$ but I can't extend this to $3$ variables. I am fairly sure that at least one of the numbers has to be negative, which might be why they specified absolute values. I have tried some random values but nothing works.   I would like to specify that this is not a homework problem, it is part of my preparation for an upcoming olympiad. This is the first problem of this sort that I have encountered, which is why I would prefer hints and general solutions over a complete solution. Thank you for your time.


90s sci-fi series: at the beginning a teen falls through a hole into a spaceship

I'm looking for a sci-fi series I watched in the 90s that at the beginning a teen fell through a hole in the sand into a spaceship. Later on a group is formed called the children of something that I don't remember. I know that at some point in the series there's an Egyptian theme where they discover that a pharaoh was also one of that group called the children.


I'm stuck at this algebra problem, it seems to me that's what's provided doesn't even at all.  Provided:  $$a+b+c=0$$  Find the value of:  $$\frac{a^2}{2a^2+bc}+\frac{b^2}{2b^2+ac}+\frac{c^2}{2c^2+ab}$$  Like I'm not sure where to start, and the provided clue doesn't even make sense.  There's no way I can think of to factor this big polynomial into a form like $a\times p+b\times q+c\times r=s$ where $p,q,r,s\in\mathbb{Z}$.  Thanks!


Regex check for alphanumeric and length between '-'

I am trying to do a regex check for an alphanumeric string that takes the following format:      45fe47hu-f8b9-40ef-c30b-b07fdb726a9e    so i need to check that the string is alphanumeric and follows the format 8-4-4-4-12.  Am currently using   preg_match('/[^a-z_\-0-9]/i', $string)   to test for alphanumeric but not sure how to check the length of the values between hyphens.


java.lang.NullPointerException: Attempt to invoke virtual method ....... on a null object reference

I'm using the android Volley to connect to server.The stringRequest POST is used to do the same          StringRequest strReq = new StringRequest(Method.POST,                 AppConfig.URL_LOGIN, new Response.Listener<String>() {             @Override             public void onResponse(String response) {                 Log.d(TAG, "Login Response: " + response.toString());                 hideDialog();          }, new Response.ErrorListener() {              @Override             public void onErrorResponse(VolleyError error) {                 Log.e(TAG, "Login Error: " + error.getMessage());                 Toast.makeText(getApplicationContext(),                         error.getMessage(), Toast.LENGTH_LONG).show();                 hideDialog();             }         }) {              @Override             protected Map<String, String> getParams() {                 // Posting parameters to login url                 Map<String, String> params = new HashMap<String, String>();                 params.put("email", email);                 params.put("password", password);                 Log.e(TAG,email+password);                 return params;             }          };         // Adding request to request queue          AppController.getInstance().addToRequestQueue(strReq,tag_string_req);     }   But it shows the following logcat error when I click the button  FATAL EXCEPTION: main Process: com.baellife.test.baellife, PID: 5285                                                                              java.lang.NullPointerException: Attempt to invoke virtual method 'void com.baellife.test.baellife.AppController.addToRequestQueue(com.android.volley.Request, java.lang.String)' on a null object reference                                                                               at com.baellife.test.baellife.LoginActivity.checkLogin(LoginActivity.java:185)                                                                                at com.baellife.test.baellife.LoginActivity.access$200(LoginActivity.java:32)                                                                                at com.baellife.test.baellife.LoginActivity$1.onClick(LoginActivity.java:80)                                                                                at android.view.View.performClick(View.java:5204)                                                                                at android.view.View$PerformClick.run(View.java:21153)                                                                                at android.os.Handler.handleCallback(Handler.java:739)                                                                                at android.os.Handler.dispatchMessage(Handler.java:95)                                                                                at android.os.Looper.loop(Looper.java:148)                                                                                at android.app.ActivityThread.main(ActivityThread.java:5417)                                                                               at java.lang.reflect.Method.invoke(Native Method)                                                                               at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)                                                                               at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)    It seems strReq in   AppController.getInstance().addToRequestQueue(strReq, tag_string_req);   is returning NULL.


Show that $A$ defined by a continuous function is open

Consider a continuous function defined all of $R^n$ i.e., $h:R^n \to R$. Also obtain the infimum of $h$ $$ a: = \inf_{x\in R^n} h(x) $$  Define the set $A := \{ x \in R^n : h(x) > a \}$. Is $A$ open?  I was trying to show that it is open. If $A$ is all of $R^n$ then it is open. We will consider the case when $A \subset R^n$. If $A$ is a strict subset of $R^n$ then its complement exists. Denote it by $A^c$. Also, since $h(x)$ is defined over all $R^n$ and $a$ is the infimum, we can obtain $A^c$ explicitly as $$ A^c = \{ x \in R^n : h(x) = a \}$$  It remains to show that $A^c$ is closed. Suppose that $A^c$ is not closed. Then there is a sequence of points in $A^c$: $x_1, x_2, \dots$ such that $\lim_{n\to \infty} x_n  \notin A^c$. This is a contradiction since $h$ is continuous and  $ h(x_n) = a$ for every $n$, and its limit is $a$.  Did I get this right? Is there a better proof?


My PC has "invisible" files that take up 100GB+ of space

I have a Lenovo T460 (with a 256GB SSD), and it is almost full even though I only have around 120GB of files on it. I tried using , but it only showed the files that I already knew about, and left a mysterious 100GB out. Does anyone know what is going on?  EDIT: To clarify, WinDirStat does not show those files AT ALL.


Proof that Fibonacci Sequence modulo m is periodic?

It's well known that the Fibonacci sequence $\pmod m$ (where $m \in \mathbb N$) is periodic. I have figured out a proof for this, but upon googling, I found proofs online that were far more complicated. This leads me to suspect that my proof may be fallacious - that's why I am posting here.  Proof:  Let us list out the Fibonacci sequence modulo m, where m is some integer. It will look something like this at first (for $10$ at least):  $$ 1,2, 3,5,8, 3,1, 4, 5, 9, 4, 3, 7 {\dots}$$  Obviously, any number in the sequence is the sum of the last two numbers modulo $m$. Therefore, if at any point in the series modulo m a pair of numbers repeat, the numbers following that pair must repeat as well. eg. if at some point later we see the pair $1, 1$, then $2, 3, 5, \dots$ must follow that pair.  Now there are $m^2$ possible pairs in the series $\text{mod} m$. By the pigeonhole principle, after $m^2 + 1$ terms, a pair must repeat. If a pair repeats once, it must repeat again the same number of terms later. Therefore, the Fibonacci sequence $\pmod m$ is periodic $\forall m$ .  Is my proof correct?


Can you cast a Subtle Spell while under the effects of Hold Person?

Let's say that you're a Sorcerer under the effects of Hold Person, can you cast a spell without a material component with the Subtle Spell metamagic?


Let $f(x) = \frac4\pi \cdot (\sin x + \frac13 \sin (3x) + \frac15 \sin (5x) + \dots)$. If for $x=\frac\pi2$, we have $$f(x) = \frac{4}{\pi} ( 1 - \frac13 +\frac15 - \frac17 + \dots) = 1$$ then obviously :  $$ 1 - \frac13 +\frac15 - \frac17 + \dots=\frac{\pi}{4}$$ Now how can we prove that: $$\frac{\pi^2}{8} = 1 + \frac1{3^2} +\frac1{5^2} + \frac1{7^2} + \dots$$


How do i cut out a shape from multiple objects with different fills?

I want to cut out some text out of a rectangle made up of different objects with different patterns as fillings so that I end up with the text in negative space, but whatever I try, it doesn't work. I tried clipping mask, pathfinder, making a mask and inverting it. Nothing seems to work. In the picture, you can see the artboard with the shapes filled with patterns. In black the text that I want to cut out. I already changed the text into outlines. All help and tips are welcome!


I would like to report a bug.  was apparently closed 2 years ago, but it has only existed for 1 year and 3 months. See a screenshot of the problem below.


How do you interpret a significant but weak correlation?

I have carried out a number of Pearson Chi Square tests on the relationship between tail lesions and abscessation in pigs. I have found a significant (p = 0.005) but weak (r = 0.288) association. How do I interpret this?  For example, does this mean that there is a clear relationship between the two but that it is just on a small scale?


Host multiple website using nginx on the same IP

I've set up a Raspberry Pi to act as web server, so I've installed nginx with php5 and I bought two domains:   domain1.co.uk Domain2.it   I have a static IP which is linked to these two domains, so if I type one or the other I get the same example web page that I wrote.  How could I do to set a directory for a domain and another for the other domain?


Can we get a way to wrap text around images?

Right now as far as I can tell all images have to appear as inline paragraphs, left-aligned with other paragraphs.  For sites like Stack Overflow, it makes sense... images are only used when you want to illustrate something, so the image is sort of like something that they have to stop and "read".    On some of our newer sites, like , images can serve a more decorative function, making questions and answers look awesome and interesting. For example, when somebody asks about trains in Mongolia, an answerer might write an extensive answer and then attach a picture showing them standing in front of a train in Ulan Bator.  For these "decorative" pictures, it makes a lot more sense if they are floated to the right and text wraps around them. Otherwise they interrupt the text and, frankly, look kinda ugly.  I suggest something simple like $[...] instead of ![...].


Can't Boot From DVD or USB Stick after Boot-Repair

I have a dual boot with Windows 10.  I was unable to boot Ubuntu from disk.  I have a bootable USB stick and that worked.  I booted from the USB and then booted a recovery Ubuntu option in Grub.  Then, I was able to get into my Ubuntu partition.  I was updating my system when the machine just shut down.  After which, I ran Boot-Repair.  Now, I can boot from my Ubuntu partition, but once I enter my password, the screen is all messed up and I can not Login.  It doesn't seem to recognize my password.  Also, now, I can not boot from my USB Ubuntu Stick.  I made a brand new Ubuntu ISO image and that will not boot either.  (A reinstall previously fixed the screen problem.)    I have tried changing the boot order in the BIOS.  That does not help.  The link to the Boot-Repair log is above.  Any help would be greatly appreciated.


Trying to find an XML file I can use in lieu of a look-up database table until we get our web hosting switched over to the right DB.  Can anyone refer me to an XML file with elements whose children have zipcodes, states, and cities? E.g.:  <zip code="98117">     <state>WA</state>     <city>Seattle</state> </zip>   Or  <entry>     <zip>98117</zip>     <state>WA</state>     <city>Seattle</city> </entry>   I'll be using LINQ in C# to query this data.


How do I recompile Bash to avoid Shellshock (the remote exploit CVE-2014-6271 and CVE-2014-7169)?

Given that Bash 3.2 (the version shipped by OS X) is vulnerable to the  known as "Shell Shock" ( and ) how do I rebuild Bash and secure my system ahead of an official Apple patch?  UPDATE: Note that Apple has now released the official patch.  for details.


2 boxes of money, unknown money inside, one is twice the amount of the other

Suppose, I have two boxes. A host is telling me to pick one. I see the money inside of this one - say 100 \$. Now, I need to decide if I want to swap, given the information that the other box has twice less or more money - say 50\$ or 200\$. Thereofre, expected value of the second box is clearly 125 \$. Question 1: Does this apply that I need to always swap? Question 2: If I repeat the experiment 1000 times, where the money inside of the boxes is some random $N>0$, does it matter if I swap? Does it have to do something with the law of large numbers?


Failed to download repository information, software & update useless

I know there's a lot of post with that same problem. But I can't seems to find one that help my case, so here we go.  When I try to update via software updater I got the message « Failed to download repository ». My internet connection is fine. When I try by terminal does not work either, I think thoses lines illuminate the problem:  Hit:8 http://ppa.launchpad.net/ubuntuhandbook1/audacity/ubuntu artful InRelease Err:7 https://content.runescape.com/downloads/ubuntu trusty InRelease   The following signatures were invalid: AAC9264309E4D717441DB9527373B12CE03BEB4B W: GPG error: https://content.runescape.com/downloads/ubuntu trusty InRelease: The following signatures were invalid: AAC9264309E4D717441DB9527373B12CE03BEB4B E: The repository 'https://content.runescape.com/downloads/ubuntu trusty InRelease' is not signed. N: Updating from such a repository can't be done securely, and is therefore disabled by default.   Also I'm not able to change anything from the software & update menu, I cannot check or uncheck any item..  I am really new to all this, please forgive my lack of ressourcefulness and thanks in advance for your time!


decimal representation of $2^m$ starts with a particular finite sequence of decimal digits

Given a finite sequence of decimal digits $a_1,a_2,...,a_n$ prove that there exists a natural number $m$ such that decimal representation of $2^m$ starts with that sequence of digits.  Thanks for your help :)


I want to remove the header, but I am not sure how to do this. I cannot remove the line in the header. This is the code I am using: \usepackage{sectsty,fancyhdr} \sectionfont{\LARGE\bfseries}% https://tex.stackexchange.com/q/59726/5764  \pagestyle{fancy} \fancyhf{} \lhead{Project tile} \renewcommand{\headrulewidth}{2.0pt} \renewcommand{\footrulewidth}{0.5pt}  \rfoot{Page \thepage} \lfoot{\leftmark}  \makeatletter \renewcommand{\sectionmark}[1]{%   \markboth{\ifnum \c@secnumdepth>\z@       \thesection\hskip 1em\relax     \fi #1}{}} \makeatother


Ask for a password in POSIX-compliant shell?

When I want to ask for a password in a bash script, I do that :  read -s   ...but when I run bash in POSIX mode, with sh, the -s option is rejected:  $ read -s sh: 1: read: Illegal option -s   How do I securely ask for an input with a POSIX-compliant command ?


Cant get around Strings beeing immutable

I am writing a method that returns a String with the specified letter doubled but it only returns the original value of s. I am relatively new to java and think this is due to Strings being immutable in java but I am not sure how to work around it. Any help with this method would be appreciated.  public static String doubleSpecificLetter(String s, String letter){         String s2 = s;         for(int i = 0 ; i < s2.length() ; i++) {             if(s.substring(i, i + 1) == letter) {                 s2 = String.join(letter, s2.substring(0, i + 1), s2.substring(i + 1));             }         }          return s2;     }


How can I write a paper that will convince the reviewers that the results are non-trivial?

I submitted a paper in math/cs/economics to a top-level journal. The paper involves a new variant of a well-known problem. All reviewers agreed that the results are interesting and non-trivial, but they rejected the paper as not being general enough for their journal.  Encouraged by the positive feedback, I submitted an improved version of the paper to a medium-level conference. The improvements include simplifications of some of the proofs and additions of stronger results about the same problem. Now the reviewers rejected the paper claiming that the results are too weak and unsurprising!  What should I do in the next time I submit (to a different journal), in order to make the reviewers believe that the results are indeed surprising and non-trivial? I don't want to write the proofs in their more complicated version, as in the first revision, because this is unscientific. But writing it in a simple way seems that doing so creates a false impression that the results are too simple. What do you suggest?


Draw "less than functions" in tikz graph

I would like to know how to draw the "less than" or "greater than" lines in a tikz graph. i found this nice graph but am unable to draw the "zebra-lines". Is there a package for this?  For my plots I'm currently using pgfplot \documentclass[12pt, a4]{article} \usepackage{pgfplots} \pgfplotsset{compat=1.16}  \begin{document} \begin{figure}[h]     \begin{tikzpicture}         \begin{axis}[             axis x line=center,             axis y line=center,             xlabel=$x_1$,             ylabel=$x_2$,             xmin=-1,             ymin=-1,             xmax=8,             ymax=15,             xtick={-1,0,1,2,...,8},             ytick={0,2,3,4,6,8,10,12}         ]         \addplot[mark=none, domain=-1:8] {-4*x + 8}; % -4x_1 -x_2 <= -8         \addplot[mark=none, domain=-1:8] {x + 3};         \addplot[mark=none, domain=-1:8] {2};         \addplot[mark=none, domain=-1:8] {-2*x + 12};         \addplot[fill=blue!20,draw=blue]coordinates{(1,4)(3,6)(5,2)(1.5,2)};         \draw[red, ->](3,6)--(3,9);         \node[label={180:{(3,6)}}, circle, fill=red, inner sep=2pt] at (axis cs:3,6) {};                  \end{axis}     \end{tikzpicture} \end{figure}  \end{document}  which looks like this:


Linker causes problem when compiling template c++ while passing lamda functions

I have a function with this signature. template<class F, class... Args>     auto enqueue(F f, Args &&... args)     -> std::future<typename std::result_of<F(Args...)>::type>;  It is present in a header file along with a corresponding implemetation in a c++ file. From another file, I call it. pool.enqueue([](control &c, float arg){return c.move_ver(arg);}, *player_c, SPEED(key_state));  I get the following error when compiling function 'thread_pool::enqueue<(lambda at /Users/{username}/code/C/opengl/one.cpp:75:22),  control &, float>' is used but not defined in this translation unit, and cannot be defined in any other translation unit because its type does not have linkage  It compiles fine if the function is called from the same file where it is declared. I am prettty sure it is a linker error. I am compiling on MacOS with apple clang.


Order of hyperparameter optimisation and feature selection in a nested CV structure

I am currently trying to build an ML pipeline for fMRI data. To get an unbiased estimate of the performance of my pipeline, I use nested cross-validation structure. However, I am not sure in what order hyperparameter optimization and feature selection should be in a nested CV structure. I have four options (but always open for good options):   3-loop nested cross-validation.   Outer loop: Model evaluation Middle loop: Feature selection Inner loop: Hyperparameter optimization    3-loop nested cross-validation.   Outer loop: Model evaluation Middle loop: Hyperparameter optimization Inner loop: Feature selection    2-loop nested cross-validation   Outer loop: Model evaluation Middle loop: First feature selection, then hyperparameter optimization    2-loop nested cross-validation   Outer loop: Model evaluation Middle loop: First hyperparameter optimization, then feature selection   Please keep in mind that, fMRI studies generally consist of a small sample (around 20-30 per category) unless you are working on connectomics projects.


I have studied what a differentiable manifold is, and what a tangent space at a given point is, and read the proof that its dimension is equal to the dimension of the manifold. Here a tangent vector is a derivation on the germs of differentiable functions at a point.  Now I am trying to see that the tangent bundle is indeed a differentiable manifold. I get that for an open set $U$ in Eucliden space, it takes the form $U \times \mathbb R^n$ with the vector $\sum a_i x_i$ giving the tangent vector $\sum a_i \partial /\partial x_i$. Now the book says that it is "obvious" that these glue up and give a differentiable manifold.  I may be stupid; but I will be grateful if somebody can hold my hand through this "obvious" statement.


proving $\lim\limits_{n\to\infty} \int_{0}^{1} f(x^n)dx = f(0)$ when f is continous on [0,1]

$$\lim\limits_{n\to\infty} \int_{0}^{1} f(x^n)dx = f(0)$$  when f is continuous on $[0,1]$  I know it can be proved using bounded convergence theorem but,  I wanna know proof using only basic properties of riemann integral and fundamental theorem of calculus and MVT for integrals ...   Thank you.


Counting traversed arcs on routes to write attributes using ArcGIS for Desktop?

I have number of persons located on a road network and I have calculated their shortest distance to a particular location.  From the routes output created from Closest Facility can I   break the routes down into the individual arcs traversed by each person? assign each arc a count attribute indicating the number of individuals who use that arc to get to their destination?   I am using Network Analyst in ArcGIS 10.2 for Desktop.


How to play on lan with friends on minecraft

so i've checked all the other questions similar to this and i tried them out and they didn't work (how to add minecraft as a firewall exception for instance) and i've searched the question up on youtube and stuff but that didn't work either


Beamer Warsaw theme: Reduce the number of subsections visible in the navigation bar

I give a lecture with 10 sections and maybe 5-10 subsections. Using the Warsaw theme would make the available space too small.   Is there a way to make the navigation bar show:   only the last section, current section and the next two sections? only the last subsection, current subsection and the next two subsections?   If there is not an option, one may have to change the \insertsubsectionnavigation-function.  Maybe something like   \insertsubsectionnavigation["\thissectionnumber-1" to "\thissectionnumber+2"]    The problem is: I don't understand the way this function works.  Does anyone have an idea or a link to a similar topic?  Here is an example of how it should NOT look:  \documentclass{beamer} \usetheme{Warsaw} \begin{document}     \section{Section 1}     \section{Section 2}     \section{Section 3}     \section{Section 4}         \subsection{SubSection a}\begin{frame}Test\end{frame}         \subsection{SubSection b}\begin{frame}Test\end{frame}         \subsection{SubSection c}\begin{frame}Test\end{frame}         \subsection{SubSection d}\begin{frame}Test\end{frame}         \subsection{SubSection e}\begin{frame}Test\end{frame}         \subsection{SubSection f}\begin{frame}Test\end{frame}         \subsection{SubSection g}\begin{frame}Test\end{frame}         \subsection{SubSection h}\begin{frame}Test\end{frame}         \subsection{SubSection i}\begin{frame}Test\end{frame}     \section{Section 5}     \section{Section 6}     \section{Section 7}\begin{frame}Test\end{frame} \end{document}   A slide would look like:   I want it to look like:


The Pythagoreans proved that the length of the diagonal of a square with side length 1 is not a rational number. Prove that the length of the diagonal of a rectangle with sides length 1 and 2 is not a rational number. When trying this problem, I did the pythagorean theorem. I think that is too simple.


Advice On Alternative To Using Many Dozens Of Check Boxes In An Asp.Net User Interface

I have a table that has 51 bit values to hold the values of statutes.  In production, this table would have over 10,000 records for the different LocationID's.  The UI for this in its pure database form would have a page with the dozens of text boxes.  Is there a better, cleaner way to do this?  Any recommendation or links to how others have handled this situation ?


I know rank AB is not same as rank BA.    I take here particular case.  Is this particular case true?


Home Ethernet - Connecting a second router to extend wifi

My primary router has trouble extending wifi coverage to some bedrooms in the house so I am planning to add a second router to extend the wifi network using the wired Ethernet ports in one of the areas of poor coverage. Basic layout -   The ISP's router is in my family room downstairs (fiber connection) and the internet connects to the fiber via a box in an upstairs closet.   I purchased and installed an unmanaged Ethernet switch/splitter. In the upstairs closet where all of the Ethernet wires meet, the family room Ethernet cable was plugged into the ISP's box. I disconnected this wire and replaced it with a CAT5 cable running from the ISP's box in the closet to the Ethernet switch's port 1.  I think connected the family room Ethernet cable to port 2 and did the same in order for all the remaining Ethernet cables to various bedrooms.   So far, the switch is working fine.  I have wifi working with internet coming off of the router in the living room so I believe the switch is installed correctly otherwise that wifi should not have internet coming off of the living room jack.   Here is where things go awry - I took my second wifi router and connected the WAN/Yellow port to the Ethernet wall jack in another bedroom.  I then connected a lap top to one of the Ethernet ports on this router and found "no internet" after connecting.  On a whim, I changed the connection so that the router was connected to the Ethernet wall jack in one of the white ports but with the same results.   I don't think this counts as cascading and I don't really need a new network since I do not share the connection with any non-family members.  The router has been reset to factory settings to clear out any old instructions - but I still can't get it to connect to the internet or access the router to change the settings even - it's a netgear and the routerlogin.net will not let me access the router even when I am on the working WIFI for internet and have a cable running from the laptop to the netgear router.   I could use some help - just trying to extend the wifi range and it seems like it should be much less complicated. Tried following instructions in several other posts and they did not work for me - because I cannot access the router to change any settings.


If $2xy$ divides $x^2+y^2-x$, prove that $x$ is a perfect square

This problem is from  ( BMO Exam1991 ). I tried to solve but it was difficult.  The problem is:      If $ x^{2} + y^{2} - x $ is a multiple of $ 2xy $ where $x$ & $y$ are integers, prove that $x $ is a perfect square.   Any help or hint please.


How to cover scheduler class in test class?

I am writing test class how to cover scheduler class in test class.  Class:  global class updatecontactaccount implements database.batchable<sobject>,schedulable{     global database.querylocator start(Database.Batchablecontext BC)     {         string query = 'select id,name,accountnumber,(select id,lastname,accountid from contacts) from account where name = \'testaccount\'';         return database.getquerylocator(query);     }      global void execute(Database.Batchablecontext BC, List<account> Scope){         list<contact> listcon = new list<contact>();         map<string,contact> oldmap = new map<string,contact>();         map<string,contact> newmap = new map<string,contact>();         account acc = [select id,name,(select id, lastname from contacts) from account where name=: 'BICS'];             for(contact a : scope[0].contacts){                 oldmap.put(a.lastname,a);             }             for(contact c : acc.contacts){                 newmap.put(c.lastname,c);             }             for(contact c : oldmap.values()){                 if(!newmap.containskey(c.lastname))             {             c.accountid = acc.id;                 listcon.add(c);                                                     }             }             system.debug('contact:'+listcon);             update listcon;     }     global void finish(Database.Batchablecontext BC){     }  global void execute(schedulablecontext sc){     updatecontactaccount up = new updatecontactaccount();     database.executebatch(up);     } }   Test Class:  @istest public class Updatecontactaccount_Test {     static testmethod void testbatch(){         account a = new account();         a.name = 'testaccount';         insert a;         contact c = new contact();         c.lastname = 'Test';         c.accountid = a.id;         insert c;         account acc = new account();         acc.name = 'test11';         insert acc;         contact con = new contact();         con.lastname = 'Test11';         con.accountid = acc.id;         insert con;         updatecontactaccount up = new updatecontactaccount();         database.executebatch(up);      } }


If $n=\frac{a}{b}$ , with $n, a$ and $b$ integers $( b ≠ 0)$, and with $a$ and $b$ coprimes, does $b=1$?

If  $n = { \dfrac{a}{b} }$ , with $n$ ${ \in }{ \mathbb{N} }$, $a$ ${ \in }$ ${ \mathbb{N} }$, and $b$ ${ \in }$ ${ \mathbb{N^*} }$ , and if $a$ and $b$ are coprime, then does $b$ $=$ $1$ ? I can only see that as an option, but I'm not enirely sure. A little help ? Thanks.


Reference label with included file and relaxed clearpage

I am running into a rather weird error that apparently originates from the combination of \include, \let\clearpage\relax and a referenced label after a page break.  In this particular example, the label mylabel defined in the listing cannot be referenced anymore when the reference and the label are close enough to a page break.  The MWE consists of two files, the main-file and an included file. I am using the \let\clearpage\relax command to . The error does not occur if the file is \input instead of \included.  \documentclass[11pt,twoside]{book} %  \usepackage[utf8]{inputenc} % Enoding \usepackage[english]{babel} % Language \usepackage{listings} \usepackage{forloop}  \begin{document} \begingroup \let\clearpage\relax  \include{includedfile} % changing include for input would work  \endgroup \end{document}   Included file:   \newcounter{ct} \forloop{ct}{1}{\value{ct} < 40}% {%     .\\ }  Listing \ref{mylabel}.  \begin{lstlisting}[caption=somecaption, label=mylabel] some code; \end{lstlisting}   Running this example will have an output where the label cannot be referenced (even after multiple runs):    Now, one solution is to use \input as mentioned earlier but I am rather interested in why this happens. Does the \clearpage command fulfil an important function for references to work? And can the error be avoided without removing \let\clearpage\relax while using \include?  EDIT: I just found  with the same issue (though it does not have a definite answer).


Poisson-Gamma conjunction - calculating posterior

How to calculate posterior distribution step-by-step while given:   some observed numbers of customers from the last days that number of clients is distributed by Poisson($\lambda$) ($\lambda$ is not given) that prior distribution of $\lambda$ is Gamma(a, b)   And after that, how to calculate ptobabilities of getting x number of clients the next day?


C# - Encrypting and Decrypting Using external RSA Keys

I'm working on a project that includes Encrypting and Decrypting between different parties.  The keys are generated using 'phpseclib' () on a remote server using RSA class.  The keys are in the following format:  Public:  -----BEGIN RSA PUBLIC KEY----- MIGIAoGAUEAW3K4+77Q1XrbdE/Sat7l9LXcD8qUdDGzSMubWXARMj8xtaPnVj7Ec 81HU5lKbFO31tV9nPSNeApNkkZtQhxx0Gz2gQgiChiuhcmlmNdnzEXFFpwa+uo2i fR5BLkNNy+qldhLqHg6yK7y0CrMKJUjfH2PKU+a5VectKkxPmDsCAwEAAQ== -----END RSA PUBLIC KEY-----   Private:  -----BEGIN RSA PRIVATE KEY----- MIIDHQIBAQKBgFBAFtyuPu+0NV623RP0mre5fS13A/KlHQxs0jLm1lwETI/MbWj5 1Y+xHPNR1OZSmxTt9bVfZz0jXgKTZJGbUIccdBs9oEIIgoYroXJpZjXZ8xFxRacG vrqNon0eQS5DTcvqpXYS6h4Osiu8tAqzCiVI3x9jylPmuVXnLSpMT5g7AgMBAAEC gYAb/L38aKh6XjDbXb2jFVQ3sxx3EQACbVVKo1e3LQY+YrMjSGsKS2TAbiMaNebF 7RPRFQfJ2gWSshDj0oCPg0U7WkEsFla5gIl3zJrVbeNnC9jyzZ/LgCnZIKiDcMXv r0plq6HxcHJWcHecpKhfzvfmd26/U6DhL0kP54FWOf8AAQIJAIEyQC7c5gxXAgkA 5JFBPI+4/msCCD80lE3Y5/rVAgkApkPHeb9uqZsCCATuDv0RSFtXMIIB1jAfAgkA uKLVRgl4zqkCCAae4CLoyAoxAggHXPQwQgmTOTAhAgkA6CnMpA9djC0CCQCBPmPS IUuusQIJANRRQ8thKK4UMB8CCQC1KlBjMihEawIIGOMeNfJO+88CCHdqK2B+eQLs MB8CCQC4HwiUnQVuLQIIaOjV3MfzdikCCHI4iaUvtcqGMB8CCQCUKg9il+fkPQII VDo01M+WO+ECCEq17+pHX2OtMB8CCQCIZvXiOx/PbwIISPda/URHhf0CCFsVg61b 83D6MCACCQCwPqvRmoiStwIJAKF1mKSaJLn7Agh2FqM8iF6xmjAfAgkAlGuCK9lO /IMCCCKkiWi0u1QDAggnJIDr4YyD3jAfAgkAhL2jhjw0DKsCCETMxeTdb1zhAghQ V9S+12JvPzAfAgkA+6wy7oV1aocCCC3YBkcQpHzNAghOrrC+Nc3tgTAgAgkAxDf5 kZMTkUcCCQCqYJg5yWWyPQIIF1zKmIUwDGQwIAIJALbjlmSjpLg9AgkAqRV0P4sD iMkCCAH9Ncvav/KFMCACCQDpSAEmE4WkowIIMH6/fmLgjXECCQCYz0JvH95z5DAh AglCvzjdoEVfNPcCCT/8Id5LatUm5wIJCrp28jLZ/NOw -----END RSA PRIVATE KEY-----   I was trying to use the 'RSACryptoServiceProvider' for the  Encrypting and Decrypting but I was unable to find a way to convert the PEM format to the XML format the RSA Crypto Service Provider requires.  Any suggestion how can that be done ?  Thanks !


Why is my stored procedure very much slower than the same MYSQL query?

My stored procedure is very slow compared to a normal query or a temporary table. How can I optimize my stored procedure?    CREATE DEFINER=`datasll`@`...` PROCEDURE `product`()   BEGIN   EXPLAIN SELECT            cs.id,          cs.fk_c,          cs.so,           cs.pr,          cs.date,          cs.o_p,          cs.sh_c,          cs.x,          LEFT(cs.x,2),          cs.doc,          cs.fk_op,          cc.id_c_c,          cc.name,          cc.descrip,          left(cc.n_o,3) as bon,          cc.fk_c_br,          cc.de,          cc.m_mat,          cc.color,           cc.fk_c_s   FROM         data_pro.catas cs    LEFT OUTER JOIN         data_pro.c_co cc ON  data_pro.cs.fk_c_c = data_pro.cc._id_cc   WHERE         data_pro.cc.pap = 1   AND   data_pro.cc.stati = 'b';   END   When I use EXPLAIN this is the result:


How can I use a command to delete all files in Downloads whose dates added are greater than 1 year?

I am using a Mac. How can I use a command to delete all files in ~/Downloads whose dates added are greater than 1 year?


Why is this derivation of the transformation from Cartesian to polar coordinates not correct？

In the double integral, for the integrating area element, we have the transformation equality from Cartesian coordinate system $y=y(x)$ to polar coordinate system $r=r(\theta)$: $${\rm d}\sigma={\rm d}x{\rm d}y=r{\rm d}r{\rm d}\theta.\tag{1}$$ But if we let $$x=r\cos\theta,~~~y=r\sin\theta,$$ then $${\rm d}x={\rm d}(r\cos\theta)=-r\sin\theta{\rm d}\theta+\cos\theta{\rm d}r,~~~{\rm d}y={\rm d}(r\sin\theta)=r\cos\theta{\rm d}\theta+\sin\theta{\rm d}r.$$ Therefore \begin{align*} {\rm d}x{\rm d}y&=(-r\sin\theta{\rm d}\theta+\cos\theta{\rm d}r)(r\cos\theta{\rm d}\theta+\sin\theta{\rm d}r)\\ &=-r^2\sin\theta\cos\theta d^2 \theta+r(\cos^2 \theta-\sin^2 \theta){\rm d}r{\rm d}\theta+\sin\theta\cos\theta{\rm d}^2 r.\tag{2} \end{align*} But the result is not correct. What's the reason? I know the right result $(1)$, and I just wonder why $(2)$ is not right.


Dual Citizenship Travel in Europe For Extended Stay

I'm trying to figure out the best way to have an extended stay in Europe and was wondering if this was possible with dual citizenship.  If I had a US and Singaporean passport, and traveled to a country in the Schengen area, either passport would give me a 90 day visa in a 6 month period.  Would this loophole be considered "legal" if say I travel to Spain using my Singaporean passport for 90 days, then went to UK or Ireland using my US passport, and reentered the Schengen area using my US passport. This would technically be me renewing my 90 day visa without needing to wait 90 days before doing so.


There is a question  about something similar, but it's asking about the internals of an op-amp. I'm having trouble understanding the function and use despite several hours of YouTube tutorials.         – Schematic created using   I'm having an awful time figuring out how this works...and EXACTLY what it does.   From what I understand:  1) Op-Amps compare the voltage between the non-inverting input and the inverting input, then multiply the difference by an almost infinite number and that product becomes the output. (I.E. Gain) 2) The inputs neither draw nor output any current.   This configuration should make it so that the inputs are always at the same voltage.   I'm not sure I understand the purpose of this configuration, and I certainly don't understand how negative feedback works to produce that effect on the inputs.


How to change default action for file types?

There is a certain text editor that I would like to set as the default editor for certain file types but if I try selecting it on the “Open With…” menu, that does not work. However, it has put an explorer context menu item in, which does work. How could I make this menu item the default double-click action, for certain file types?  Thank you SSRT and Josh R. Both good answers. It's a pity I can't give you both best answer.  For what it's worth, I found the answer today (twenty-four hours after asking this question).


What level of spell slot is "used" when duplicating a spell with Wish?

Wish states:     The basic use of this spell is to duplicate any other   spell of 8th level or lower. You don't need to meet any   requirements in that spell, including costly Components.   The spell simply takes effect.   If I choose to duplicate Magic Missile do I create 3 darts (level 1), 10 darts (level 8), or 11 darts (level 9)? Or can I choose how many to create from some range?  In other words, what is the level of the spell slot "used" by the duplicated spell?


Sci-fi/horror story about astronauts diving into the atmosphere of gas giant

Please help me find the title of the science-fiction / horror story about crew of astronauts-scientists diving into the atmosphere of some gas giant (like Jupiter or Saturn) inside the special space probe.  I remember only that it was very tense (pressure- and ambience-wise). The whole story takes place inside the probe and at some point they hear knocking from outside.  I've read this at least 10 years ago (maybe more). I thought it's one of the S. King's stories but I can not find it in any of his storybooks.


Can I add third party reviews to our site for the purpose of aggregate review ratings without triggering duplicate content penalties?

Is there a good way to display reviews that people have left on sites like Yelp, City Search, Google, etc on your own website without triggering duplicate content issues?   It's hard to get reviews, so I'd like to make the most out of the ones that I get.


When I try to use the following expression, the preview shows me the correct sum, but when I click ok I get this notification. This tells me it can't calculate column "Subsidie J"   It seems that it can't find the value for column "Subsidie J" but it's all in the attribute table.   Am I using the wrong expression? The value of "Subsidie J" is a CASE IF .... THEN ... END expression. Now I want the sum of these values sorted by owner.


I got a smartphone on android, and when it is attached trough USB to my computer (windows or linux), I'd like to have it ring or do notifications in the headphones of the computer.  Is there a way to do it ?


I am working on a project to create a centerline from a polygon automatically. The user select a polygon and click a button, the centerline will create for him.   I have tried the build-in function “Collapse Dual Lines to Centerline”, but it cannot perform well so I decide not use this function in this project. In further study, I find out some terms such as “Medial Axis”, “Skeleton”, “Voronoi polygon”, those are some concepts related to centerline formation. However, I find difficult to understand those algorithm.   Does anyone have a suggestion to me for this project? Does anyone have a suggestion for how to implement those concepts in ArcMap? Is there any sample script or algorithm I can refer to as reference?  Development language: C#, VB.Net ArcGIS : ArcMap 9.3.1


Bring Debian to second Position in the GRUB Menu at startup

So, I currently have BOSS Linux and I am going to install Debian (currently installing right now)   And I want my older OS (BOSS linux), on the first position and the debian, (freshly installed) to be on the second. How do I do that?


I have a copy of David Bohm's  and also a copy of T.M. Helliwell's . I was wondering if anyone has used these texts and if they're sufficient in providing an in depth inquiry into special relativity.


How do I recover the content from Notepad when the task froze?

If Notepad (the Microsoft Notepad that comes preinstalled with Windows, in my case Windows 7) froze before I had a chance to save the content to a file, is there a way to recover the content? Notepad does not have some kind of "backup" on the hard disk. I don't think in any windows version does notepad keep any data on disk.   It's all in the memory, or if you opened an existing file that has already been stored on disc all the changes are in the memory. So if the task is still there just frozen, the memory should still be there. I got the idea from my first attempt to resolve the issue by "unfreezing" notepad (see ). If unfreezing doesn't work, the problem remains of recovering the data.  Please note, this is a very different scenario form the one stated in the following question:  There the memory is wiped clean because of the reboot, in my case all the data is still in the memory.


'expr: syntax error: unexpected argument' - result from alias

I recently added an alias to my .bash_aliases file:   alias runhole="perfect && cd data_series_test && doa=$(ls -1 | wc -l) && a=$(expr $doa / 2 ) && perfect && cd data_series_train && dob=$(ls -1 | wc -l) && b=$(expr $dob / 2 ) && perfect && python3 train.py > results_$b'_'$a"   and now when I open my terminal I have the error echoed twice:  expr: syntax error: unexpected argument ‘2’ expr: syntax error: unexpected argument ‘2’   I wanted to output a file called results_a_b where a and b are values defined in counting the files in folders defined in the alias, but instead the command outputs results__


Why are the doctors always calling each other by their last names?

In Dr. House series, the doctors know each other well and are supposed to be colleagues/friends. Why not say Gregory/Robert/Eric, etc. among themselves instead of House/Chase/Foreman, etc?


I recently sent an email to a professor asking him about an administrative problem I was having, but after I'd hit the send button, I realized I'd forgot to say: "Sorry to bother you" or something of that sort in the beginning...  Now I'm wondering is that considered impolite? Shoud you apologize to professors for bothering them or does that just make you sound phony?  I greeted him with"Dear Professor X", told him who I was, asked the question, and thanked him in advance.  He answered my question and all, but I'm just asking for future reference.


Joint PDF involving independent exponential random variables

Let $X$ and $Y$ be independent exponential random variables with parameters $a$ and $b$ respectively. Let $U=\min(X,Y)$ and $$V=\begin{cases}1,& U=X\\ 0,& U=Y.\end{cases}$$ Find the joint distribution of $(U,V)$.   Since the rv's are just exponential, then the distribution of $U$ is also exponential with parameter $a+b$. Also, $P(U = X)=P(X < Y)= \frac a{a+b}$ and $P(U=Y)=P(Y < X)=\frac b{a+b}$.  However, I cannot seem to use these info to come up with the joint distribution of $U$ and $V$. Can anyone help?


How do you conquer the challenge of designing for large screen real-estate?

This question is a bit more subjective, but I'm hoping to get some new perspective.  I'm so used to designing for certain screen size (typically 1024x768) that I find that size to not be a problem.  Expanding the size to 1280x1024 doesn't buy you enough screen real estate to make an appreciable difference, but will give me a little more breathing room.  Basically, I just expand my "grid size" and the same basic design for the slightly smaller screen still works.  However, in the last couple of projects, my clients were all using 1080p (1920x1080) screens and they wanted solutions to use as much of that real estate as possible.  1920 pixels across provides just under twice the width I am used to, and the widescreen makes some of my old go to design approaches not to work as well.  The problem I'm running into is that when presented with so much space, I'm confronted with some major problems.   How many columns should I use?  The wide-format lends itself to a 3 column split with a 2:1:1 split (i.e. the content column bigger than the other two).  However, if I go with three columns what do I do with that extra column? How do I make efficient use of the screen real estate?  There's a temptation to put everything on the screen at once, but too much information actually makes the application harder to use.  White space is important to help make sense of complex information, but too much makes related concepts look too separate. I'm usually working with web applications that have complex data, and visualization and presentation is key to making sense of the raw data.  When your user also has a large screen (at least 24"), some information is out of eyesight and you need to move the pointer a long distance. How do you make sure everything that's needed stays within the visual hot points? Simple sites like blogs actually do better when the width is constrained, which results in a lot of wasted real estate.  I kind of wonder if having the text box and the text preview side by side would be a big benefit for the admin side of that type of screen? (1:1 two-column split).   For your answers, I know almost everything in the design is "it depends".  What I'm looking for is:   General principles you use How your approach to design has changed   I'm finding that I have to retrain myself how to work with this different format.  Every bump in the resolution I've worked through to date has been about 25%: 640 to 800 (25% increase), 800 to 1024 (28% increase), and 1024 to 1280 (25% increase).  However, the jump from 1280 to 1920 is a good 50% increase in space--the equivalent from jumping from 640 straight to 1024.  There was no commonly used middle size to help learn lessons more gradually.    To help focus the question a little bit, I had a project that was somewhat similar to Atlassian JIRA, an issue management system.  There were about six different types of records the client wanted to keep, all of them could potentially be related to each other.  Gathering data wasn't the core problem, although it did play a part.  The more important side of the problem was creating a system which would suggest potential relationships between the records and helped the analysts recognize patterns in the reported incidents.  There were different types of analysts that focused on the different problem domains, and due to the nature of their exploratory type of work, they didn't know what they wanted.  They just knew they had to make sense of a lot of data, draw correlations, and characterize classes of issues.    (Originally asked here: , but told that this might be more appropriate)    For the bounty: Stretch your minds a bit.  The pat answer "Make everything bigger" has a limit to how useful the answer is.  We are talking about users who have to make sense of a lot of data and find relationships between records.  If I simply bump up the size on everything they are going to be very limited in what they can see on the screen--particularly because the vertical is so constrained.


Determine all $f : \mathbb R \rightarrow \mathbb R$ such that $f(f(x) + y) = f(x^2 - y) + 4yf(x)$.

Determine all $f : \mathbb R \rightarrow \mathbb R$ such that $$f\big(f(x) + y\big) = f(x^2 - y) + 4yf(x)$$ for all $x,y\in\mathbb{R}$.   $f(x) = 0$ is obvious , but how can we find all other functions?  Thanks in advance!


In my application I have to create up to some 1000 tetraders (objects with 4 vertices, 4 faces, 6 edges). As input I get only the absolute vertex coordinates for each tetraeder. From the mathematical background I know that all tetraeders are identical but have a different location and rotation which I do not know.  The following code works (Tetra is some class providing the vertex coordinates of an tetraeder and some other informations which is not relevant here):  # object creation def draw_Tetra(Tetra, Faces):       bm = bmesh.new()     V1 = bm.verts.new(Tetra.Vertices[0])     V2 = bm.verts.new(Tetra.Vertices[1])     V3 = bm.verts.new(Tetra.Vertices[2])     V4 = bm.verts.new(Tetra.Vertices[3])      if Faces == True:          bm.faces.new((V1, V2, V3))           bm.faces.new((V1, V2, V4))         bm.faces.new((V1, V3, V4))         bm.faces.new((V2, V3, V4))             else:          bm.edges.new((V1, V2))         bm.edges.new((V1, V3))         bm.edges.new((V2, V3))         bm.edges.new((V1, V4))         bm.edges.new((V2, V4))         bm.edges.new((V3, V4))     name = "T_" + Tetra.Type + "_" + Tetra.pedigree me = bpy.data.meshes.new(name) bm.to_mesh(me) bm.free obj = bpy.data.objects.new(name,me) scene = bpy.context.scene scene.objects.link(obj)   However the script is extremely slow, e.g. to create 5000 tetraeders takes many hours. I think that I have the same problem as discussed here:    The problem is that I do not know how to use "low level code" in this special situation. Can someone give me a tip?


Can't Select All Files on Ubuntu 20.04 Desktop and other anomalies, need your help ASAP

I just installed Ubuntu 20.04 and a lot of weird things start to happen including: 1. Files from my previous OS (xubuntu) were not deleted, although i've deleted and created new partitions while installing Ubuntu 20.04 and 2. I can't select all files or all folders on Desktop! I can do it within folders but I can't use for example Ctrl + A on desktop, I can't even select all the files with a cursor, it only selects one! Please help me.


I see sentences with (he or she) like :     How to know if he or she is the best one for you?      Give a Person Power and He or She Will Show Interpersonal Sensitivity.   It's possible to use just one word instead of (he or she), something like :     Give a Person Power and He Will Show Interpersonal Sensitivity


Distribution of a function of uniform random variables

Let U, V and W be i.i.d. random variables with uniform distribution on [0,1]. Find the distribution of (U*V)^W.  I tried conditioning on the values of V and W to get a double integral over the unit square but I ended up having to integrate 1/v from 0 to 1 which is clearly wrong.


HI i have a NTFS drive insalled on my machine runing ubuntu 20.04 and on the file explorer if i go to other locations, i can see the drive and can click and view the files inside it. HOwever, when i try to copy new files into it, it says it cant and i dont have permisison to? I then right clicked the ntfs drive and when to its properties and then onto the permision option and ticked everything to allow me, owner and "others" to read/write on it but it still wont let me copy files into it? ANy suggestions?


Why is the product of all units of a finite field equal to $-1$?

Suppose $F=\{0,a_1,\dots,a_{q-1}\}$ is a finite field with $q=p^n$ elements. I'm curious, why is the product of all elements of $F^\ast$ equal to $-1$? I know that $F^\ast$ is cyclic, say generated by $a$. Then the product in question can be written as  $$ a_1\cdots a_{q-1}=1\cdot a\cdot a^2\cdots a^{q-2}=a^{(q-2)(q-1)/2}. $$ However, I'm having trouble jumping from that product to $-1$. What is the key observation to make here? Thanks!


How to stop mail() in php going into spam folder?

I am having a problem with my code when my website send register email to user, it goes into spam folder. This is the picture of email that got to spam.   It also says that via gator4168.hostgator.com which what I don't want. This is the code I am using.  function register_user($register_data){         array_walk($register_data, 'array_sanitize');         $register_data['password'] = md5($register_data['password']);          $fields = '`' . implode('`, `', array_keys($register_data)) . '`';         $data = '\'' . implode('\', \'', $register_data) . '\'';         $headers ="From:<$from>\n";         $headers.="MIME-Version: 1.0\n";         $headers.="Content-type: text/html; charset=iso 8859-1";         mysql_query("INSERT INTO `users` ($fields) VALUES ($data)");         email($register_data['email'], 'Camdrivers Member Activating Request', "Dear " . $register_data['first_name'] . ",\n\nYou have just registed in our website, Camdrivers.asia to be one of our publisher members. In order to join us, we need first to identify whether your contact email is correct or not. \n\nYou need to activate your account before you can use it. Click the link below to acctivate now:\n\nhttp://camdrivers.asia/activate?email=" . $register_data['email'] . "&email_code=" . $register_data['email_code'] . "\n\n- CamDrivers\n\n- Tel: (855)97 77 56 098 / (855)96 90 96 091\n\n- Location: Siem Reap, Cambodia",$headers);     }   Can you help me solve the problem to get all my email to be sent to inbox not spam?  Thanks


What are the most commonly used and basic Apache htaccess redirects?

This question is here so we can offer users who are looking for information on how to make one or more common or basic redirects in Apache using the htaccess file. All future questions pertaining to finding information that is that is covered by the question should be closed as a duplication of this question. .  Whats the point in this question? The idea while not perfect is catch the most commonly asked questions regarding redirects using the  htaccess on the Apache platform either on  some type of lamp or a live server. The type of answers should be generally those that you could imagine are used by 100,000’s of sites world-wide and are constantly asked here at Pro Webmasters repeatedly over and over in various forms.  A few examples of the type of answers we are looking for:   How can I redirect non-www to www? How can I redirect a sub domain to the main domain? How can I redirect a sub folder from domain to a root or a subdomain?  How can I redirect an old URL to a new URL?   A few examples of the types of answers that we are not looking for:   Answers that do not involve a redirect. Any answers relating to NGinx, IIS or any other non-Apache platform. Answers that involve custom and complex string or query removals.   Resources for Advanced to Complex Mod_Rewrite Rules:      Please note: that this question is still in construction and may need some refining either by myself or a real moderator of Pro Webmasters, if you have any concerns or questions .


How do I change the new tab page in chrome 29?

I have already researched this and all information is either for old versions of chrome or says that it's impossible.  Also, I don't want to attach any arguments to the end of chrome, like suggested   With the new tab page in chrome 29.0.1547.62, the first launch (as in, every time you launch a new chrome window when none are open) is always very laggy. It can take up to 1-2 minutes and sometimes crashes.  I use the omnibox if I want to search, I have no need for the google search bar (it's easier to use, you just press F6 and type your search) and I don't need the most visited pages.  What do I do in the newest chrome to change this?  I'm using windows 7 and the desktop version of windows 8 (two different computers)


Install ubuntu and windows 10 in dual boot

i want to install ubuntu 20.10 (1º option) and windows 10 (2º option) in my machine. I have UEFI and i read somewhere thath i dont need more to create swap etc partitions, that linux made that alone. Anyone can give me a sugestion or some link with a good tutorial. Thanks. Best Regards!


If a hobgoblin wizard had a familiar summoned, would that familiar count as an ally, thus boosting the Saving Face ability?  Saving Face: Hobgoblins are careful not to show weakness in front of their allies, for fear of losing status. If you miss with an attack roll or fail an ability check or a saving throw, you can gain a bonus to the roll equal to the number of allies you can see within 30 feet of you (maximum bonus of +5). Once you use this trait, you can't use it again until you finish a short or long rest.


Adding arbitrary code to ArcGIS ModelBuilder?

Is there any way to add arbitrary code snippets to an ArcGIS model?   I envision something similar to the "show code block" the expression builder in advanced labelling or .  For example my project of the moment could benefit greatly from fetching the username of the person running the tool. I know in python this is a simple import os; os.environ.get('USERNAME'). I think I could write that snippet to get_username.py, add it to a toolbox in Arccatalog, then add that tool to the model and use it as per-requisite model parameter for my current tool. That's a lot of work for such a small thing, and next time I might want something else, like  or a .  I think a code snippet tool or similar could be address all of these needs in a generic, broadly helpful manner.


I have two passports, one is where the visa stamp is and other has no visa stamp. What is the step to use it?

What are the steps when I travel from U.A.E to Philippines with my Indian passport where my residence visa from U.A.E was stamp and I have Philippine passport with no visa stamp on it.   What are the documents I need to carry with me?  I don't want any hassles when I travel, so urgently need some advice.


Prove that in Bell's inequality $\langle{\Psi}|\left(\bf{\sigma}\cdot\bf{a}\right)\left(\bf{\sigma}\cdot\bf{b}\right)|{\Psi}\rangle=-\bf a \cdot\bf b$

I am trying to understand how the correlation function in John Bell's paper on EPR is derived for a spin singlet state $|{\Psi}\rangle$. This is defined to be   $$ \langle{\Psi}|\left(\bf{\sigma}\cdot\bf{a}\right)\left(\bf{\sigma}\cdot\bf{b}\right)|{\Psi}\rangle=-\bf a \cdot\bf b. $$ I tried to compute it explicitly by using the Pauli matrices, but was unable to derive the scalar product of the two direction vectors.    Edit  One attempt to prove this is by using  $$ \langle{\Psi}|\left(\bf{\sigma}\cdot\bf{a}\right)\left(\bf{\sigma}\cdot\bf{b}\right)|{\Psi}\rangle=\langle{\Psi}|(\bf {a} \cdot\bf{ b})\bf I +i(\bf a \times\bf b)\cdot\sigma|{\Psi}\rangle $$ However, I am not able to derive the minus sing or get rid of the cross product term either. See the comment section


I am facing one weird situation.  I am about receive check for my kid’s summer camp refund. Summer camp agency issued a check and it was never delivered to me. When I contact them they said its already paid to me, also the same information showing in their system.  Tragedy is I never received a check.  Please guide me what to do in this situation.  I am in Queens NY.


Pop up blocker API- how to check if user has it enabled

I need to know when the user clicks on the button that triggers window.open if there is stable API/way to know beforehand if the user actively has a pop-up blocker?  In some cases the user doesn't know/pay attention that they have pop-up blocker (that block the new window). I would like to inform them by some dialog/or something to authorize a new window by clicking on allow.


keeping UV textures going from Cycles to Blender Render

So, i wanna keep my UV maps moving to Blender Render. Is it possible to do that?


User update needed after updating to Mac OS X Yosemite

A couple of days ago I updated my Macbook Pro to OS X Yosemite, the update was fine and everything seemed to be working. However since this whenever I had shut down then later logged back in or restarted my macbook I have encountered the screen pictured below.   My user profile has no picture and says [update needed] rather than my name. I can still select it, enter my password and log on. An update complete and then everything is ok. The same thing happens every time I go to log on.   Any ideas of how to solve this  Thanks


What is the Fourier Transform of $f'(x)/x$? Is it even possible to find? It's deceptively simple looking. What about $f(x)/x$?


What is the reverse word for abbreviation?

An abbreviation is a shorter form of a word (or a phrase). This need not be unique. Suppose that one abbreviation for Engineering is ENG. Hence, we would say that the abbreviation of Engineering is ENG. What would we call Engineering with respect to ENG? The "abbreviated word" does the job, but is there a more direct way of getting there? Say, the "unabbreviated"?


Is it considered harmful in the longer run to frighten the child so that he behaves the way we want?

Not sure if there is a cultural difference. In our family it is considered normal to frighten the child so that he behaves the way we want.  Example- Parent: Eat that quickly or the God will punish you! Parent: Don't go on the stairs. The ghost is hiding there and it'll catch you! Parent: Be quiet or the police will grab you!  Does this kind of behavior from the parent's side has any abnormal effects on the baby in the longer run? Can this behavior be accepted as normal?  Has any research been done on this aspect?


how can I rescale an integer array of data to an integer one?

I have an array of data.for example {25,26,11}.I want to rescale them to an array in which the summation of the 3 data is a definite value (for example 10).how can i do that?!


sudo apt-get update not working Ubuntu 15.04

Whenever I put in the command  sudo apt-get update   It returns:  Ign http://security.ubuntu.com vivid-security InRelease Ign http://us.archive.ubuntu.com vivid InRelease Get:1 http://security.ubuntu.com vivid-security Release.gpg [933 B] Ign http://us.archive.ubuntu.com vivid-updates InRelease                        Ign http://archive.canonical.com vivid InRelease                      Get:2 http://security.ubuntu.com vivid-security Release [63.5 kB]     Ign http://us.archive.ubuntu.com vivid-backports InRelease                  Ign http://archive.canonical.com vivid InRelease                            Hit http://us.archive.ubuntu.com vivid Release.gpg        Get:3 http://us.archive.ubuntu.com vivid-updates Release.gpg [933 B] Hit http://archive.canonical.com vivid Release.gpg Hit http://us.archive.ubuntu.com vivid-backports Release.gpg              Get:4 http://security.ubuntu.com vivid-security/main Sources [26.4 kB] Hit http://archive.canonical.com vivid Release.gpg                              Hit http://us.archive.ubuntu.com vivid Release                                  Get:5 http://security.ubuntu.com vivid-security/restricted Sources [28 B]       Get:6 http://us.archive.ubuntu.com vivid-updates Release [63.5 kB]              Hit http://archive.canonical.com vivid Release                               Get:7 http://security.ubuntu.com vivid-security/universe Sources [12.3 kB]      Hit http://archive.canonical.com vivid Release                                  Hit http://us.archive.ubuntu.com vivid-backports Release   Get:8 http://us.archive.ubuntu.com vivid-updates/main Sources [59.1 kB] Get:9 http://us.archive.ubuntu.com vivid-updates/restricted Sources [28 B] Get:10 http://us.archive.ubuntu.com vivid-updates/universe Sources [26.7 kB] Hit http://us.archive.ubuntu.com vivid-backports/main Sources Hit http://us.archive.ubuntu.com vivid-backports/restricted Sources Hit http://us.archive.ubuntu.com vivid/main Sources Hit http://us.archive.ubuntu.com vivid/restricted Sources Hit http://us.archive.ubuntu.com vivid/universe Sources Hit http://us.archive.ubuntu.com vivid-backports/universe Sources Fetched 253 kB in 4s (62.5 kB/s)         W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/vivid-security/Release  Unable to find expected entry 'main/binary-1386/Packages' in Release file (Wrong sources.list entry or malformed file)  W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/vivid/Release  Unable to find expected entry 'main/binary-1386/Packages' in Release file (Wrong sources.list entry or malformed file)  W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/vivid-updates/Release  Unable to find expected entry 'main/binary-1386/Packages' in Release file (Wrong sources.list entry or malformed file)  W: Failed to fetch http://archive.canonical.com/ubuntu/dists/vivid/Release  Unable to find expected entry 'partner/binary-1386/Packages' in Release file (Wrong sources.list entry or malformed file)  W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/vivid-backports/Release  Unable to find expected entry 'main/binary-1386/Packages' in Release file (Wrong sources.list entry or malformed file)  W: Failed to fetch http://archive.canonical.com/dists/vivid/Release  Unable to find expected entry 'partner/binary-1386/Packages' in Release file (Wrong sources.list entry or malformed file)  E: Some index files failed to download. They have been ignored, or old ones used instead.   Please help. I've been trying to install skype for a very long time and I've tried countless fixes.     UPDATE:   I can't install steam because of this either.


Can a UK visit visa holder apply for a Schengen visa while in the UK

My partner is awaiting a decision on his UK visit visa. If it's granted, is it possible for him to apply for a Schengen visa once he arrives in the U.K.? I would like us to go to Barcelona or maybe Paris or Rome for a few days (say 3 or 4 max)


Uninstall Windows 10 Tech Preview (reverting back to Windows 8.1)

So, I recently installed the Windows 10 Technology Preview as a full installation (not update, the setup didn't allow me to do it even if I had the same OS language). Now I'd like to revert back to my previous installation.  I tried first recovering with my recovery USB, however this doesn't seem to work. When I boot from drive and try to restore, the setup tells my that the recovery can't be applied to "Windows 10 Technical Preview".  All I got now is a "Windows.old". Is it possible to restore from that? What about registry etc?  Resources:


Need to create a combination of fields to be the primary key to determine price for a product

Our company sells products in Thailand.  However , now what they are doing is for a product , they have different prices in different regions and it is based on UOM or the region in which product is sold.  I need to create a combination of 4 fields as the primary key to determine price of a product.  By that I mean, if any of the field of 4 fields has a different value , then the existing combination.  A new price for the product will be stored.  How can I create such a key?


I'm looking for something like a standard name for a visual component, consisting of two lists and arrows between them to swap elements from one list to the other - Is there an OS or framework independent name for that?


Fewer people in the streets vs. fewer people on the streets

What's the correct or at least the most common option? Someone told me that "in the streets" means being literately in the middle of the street. On the streets means on the sides of the street. However, "fewer people in the streets" and "fewer people on the streets" have more or less the same numbers of results on Google.


Stop crontab from filling syslog Ubuntu 15.04

How can I prevent (certain cronjobs) from filling my syslog in Ubuntu 15.04? I have some jobs that run 4 times a minute and quickly fill up my syslog files.  I've tried adding:  cron.*                                                  /var/log/cron   to /etc/rsyslog.conf, but this didn't resolve anything.  The current output is:  Aug  8 06:58:01 localhost CRON[25706]: (gijs) CMD (   sleep 15; unison -batch /var/www ssh://server1//var/www) Aug  8 06:58:01 localhost CRON[25703]: (gijs) CMD (   sleep 30; unison -batch /var/www ssh://server2//var/www) Aug  8 06:58:01 localhost CRON[25708]: (gijs) CMD (unison -batch /var/www ssh://server2//var/www) Aug  8 06:58:01 localhost CRON[25713]: (gijs) CMD (   sleep 30; unison -batch /var/www ssh://server1//var/www) Aug  8 06:58:01 localhost CRON[25714]: (gijs) CMD (   sleep 45; unison -batch /var/www ssh://server1//var/www) Aug  8 06:58:01 localhost CRON[25717]: (gijs) CMD (   unison -batch /var/www ssh:// server3//var/www) Aug  8 06:58:01 localhost CRON[25719]: (gijs) CMD (   sleep 15; unison -batch /var/www ssh:// server3//var/www) Aug  8 06:58:01 localhost CRON[25690]: (CRON) info (No MTA installed, discarding output) Aug  8 06:58:01 localhost CRON[25694]: (CRON) info (No MTA installed, discarding output) Aug  8 06:58:08 localhost CRON[25588]: (CRON) info (No MTA installed, discarding output)


how to bind click dynamically added element with setTimeOut

I need to attach a dynamic click on a dynamically added element .may inside a setTimeout function. How can I use setTimeout on this element?  $('.btn').on('click', function (){   setTimeout(function(){      $('.may').click();   }, 3000); });


How well does Ubuntu work with a dual CPU computer?

I am thinking of getting a dual Intel Xeon machine, each CPU is a quad core.  Will Ubuntu utilize both processors, especially with both being quad core, optimally?  Wanting to do Video editing and processing, but the Xeon machine's clock speed is actually slower than my current computer, so if both procs are not being used, I will actually end up with a slower machine than I already have.  I am not too familiar with dual processor machines. Thanks in advance for any answers.


What gift does Clarke give his boss, Mr. Shirley in Nation Lampoons Christmas Vacation?

In the movie, Clarke gives a gift to his boss and all of the boxes are the exact same shape. Is it everyone hinted/explained what the gift was? And why they were all the same?


Prove that the area of an octagon with side a can be computed by the formula: $$S=2a^2(1+\sqrt 2)$$ I tried to prove this by the area of 8 isoscles triangles inside the octagon, but I didn't manage to find the area of those triangles.


\includegraphics cannot handle filenames that contain more than the one dot, separating the filename from the extension. Apparently it uses everything after the first dot as extension and then, of course, complains about an unknown graphics extension.  This is annoying as I very often have filenames that contain parameter values, e.g. plot_a0.4_b0.6.pdf.  Is there a way to teach LaTeX to interpret only the string behind the last dot as extension?


Do WALLS matter if I'm building the 6-inch brick defense from Corruption/Crimson for my city?

I'm aware of the Tiles required to be 6 inch thick brick for Corruption/Crimson not to spread. But does the walls (dirt walls, underground walls ...) matter?


How to add a color gradient to a picture

I felt in love with the way this graphic designer, called Mariusz, has edited this picture.  It would be fun to produce something like this for myself.   Anyone has some ideas on how to create such a nice color effect in Photoshop or Gimp?


Doing a tag only edit on a previous revision doesn't do the expected roll-back

See the revision list of . I wanted to apply the changes done in revision 5 (a tag edit), on revision 3. So essentially a roll-back to revision 3, and then the edit that was made in revision 5 (latest version at the time). The resulting revision 6 was an empty revision, without any changes. Expected: a roll-back to revision 3 with the edits done in revision 5 applied to that version of the post.


Can someone help me identify what these colons mean under these brackets?

Hi I have a python code written as followed. Can someone please explain what these colons do?  edges = (data[0,0:-1]+data[0,1])/2.0     counts = data[1,1:]


Do I have to uninstall Lubuntu when installing other Linux distros

I have a dual boot Lubuntu/windows 7 computer, but I want to installing new Linux, in this case Kali Linux from USB. I would like if my Lubuntu git purged, so do I just go in win and format the Lubuntu partition or can I install it just on top of my Lubuntu?


Why haven't I been paid yet for In-App purchases made on my app?

I have an app with one In-App Purchase item. When looking at the Payments and Financial Reports the Estimated Amount Owed is > 300 DKK (I'm from Denmark).    However, there's been no payment yet. What am I missing?  I checked in Agreements, Tax, and Banking and I have a Paid Application contract in place with Bank Info.


Positive definiteness of the matrix $A+B$

Let, $A$ & $B$ are $n\times n$ positive definite matrices & $I$ be the $n\times n$ identity matrix. Then which of the followings are positive definite?  (a) $A+B$  (b) $ABA$  (c) $A^{2}+I$  (d) $AB$  I know that, $A^{2}+I$ is positive definite, as if $\lambda$ is an eigen value of $A$ then $(1+\lambda^2)$ is an eigen value of $A^2+I$.  I think (d) is true.Suppose, $\lambda_{1}$ & $\lambda_{2}$ be two eigen values of $A_{2\times 2}$ matrix & $\beta_{1}$, $\beta_{2}$ be two eigen values of $B_{2\times 2}$ matrix.  Now, $det(AB)=det(A)det(B)=\lambda_{1}.\lambda_{2}.\beta_{1}.\beta_{2}.$  As, $\lambda_{1},\lambda_{2},\beta_{1},\beta_{2}$ are all positive so eigen values of $AB$ are all positive, so $AB$ is positive definite.  Similarly, $ABA$ is positive definite.But I am not sure & I have no idea about $A+B$.


Chance of getting UK Standard Visitor visa without booking flights for application?

Can anyone let me know if they have experience of someone who has applied for a UK Standard Visitor visa and had EVERYTHING in their application except flight bookings? Refused or accepted - anything at all.   My boyfriend has just applied for a UK Standard Visitor visa for a two week period and has proved ties in his country, proof of employment and holiday time, proof of theatre and excursion ticket bookings in the UK, train journey tickets in the UK, proof of address, his bank statements, proof of accommodation, two letters of invitation etc; just not booked flights.   So has anyone applied like this and been accepted or refused or do you know someone who has?  I'm asking to plan for if the application is refused based on flights not being booked.  Addendum: Thank you for the response - the question is does anyone have experience of a visa application being made without any flight information and if the application was refused on basis of lack of flight information or they had everything else and it was accepted. The question is not how do I book a flight without paying for the purpose of application or what do I need to put in the application, apologies if that was unclear.  As I said, the application has already been made and I am asking to make a contingency plan if necessary and considering most realistic outcomes by trying to find out if anyone has had a similar experience.


Trying to convert the arrays of an old program into generic arrays. This is the first time I've worked with generics, and I'm clearly missing something here. I'm getting an NPE when trying to push characters of a string into some dedicated stacks. I've printed the length of the arrays initialized in the evaluateExpression method and get 0.   How am I flubbing this initialization? Are my constructors not appropriate to setting each array's capacity? Am I not calling things into scope properly in main?   I've indicated in the code where I'm getting my first NPE on line 33. Other comments and rest of program is probably irrelevant. I'm not concerned if the program functions like it's supposed to, just these generic arrays.   package generics;  import java.util.Scanner;   public class GenericTesting<E> {  /**  * function converts input expression to a char array,   * which is then parsed and its elements pushed into int and char arrays  * while spaces are collected and separated from what will be equated  * @param expression prefix expression entered by user  */ public static int evaluateExpression(String expression) {     int result = 0;       char[] tokens = expression.toCharArray();     StackG<Integer> operands = new StackG<>(10);      StackG<Character> operators = new StackG<>(10);      StackG<Character> blanks = new StackG<>(10);      for (int i = tokens.length -1; i > 0; i--) {         if (tokens[i] == ' ')              blanks.push(tokens[i]);         if (tokens[i] >= '0' && tokens[i] <= '9')              operands.push(tokens[i]);          if (tokens[i] == '*' || tokens[i] == '+' || tokens[i] == '-')             operators.push(tokens[i]);      }      while (operands.getLength() != 1) {         int num1 = operands.pop();     // null pointer exception         int num2 = operands.pop();           char symbol = operators.pop();          if (symbol == '*')             result = num1 * num2;          if (symbol == '+');             result = num1 + num2;          if (symbol == '-')             if (num1 > num2)                 result = num1 - num2;              else                  result = num2 - num1;      }     return result;  }   Array Constructors, push and pop functions:  public class StackG<E>{     private E[] stack;     // holds stack elements      private E[] stack2;    // holds stack elements while stack is resized     private int capacity;  // number of elements that can be stored     private int length;    // number of currently stored elements     private static int top;       // stack top pointer  public StackG(int initialCapacity) {     capacity = initialCapacity;      stack = (E[]) new Object[capacity];       length = 0;      top = 0; }  public StackG() {     capacity = 5;      stack = (E[]) new Object[capacity];      length = 0;      top = 0;  }  public void push(Object item) {     if (top == stack.length)         throw new IllegalArgumentException(); //Stack is full     else {         stack[top] = (E) item;          top++;         length++;     } }  public E pop() {     if (isEmpty())         throw new IllegalArgumentException(); //Stack is empty     else {         top--;         length--;         return stack[top];      }  }   Client Code:       public static void main(String[] args) {      Scanner keyboard = new Scanner(System.in);       System.out.print("Enter a prefix expression "             + "using only *, +, and - operators and positive operands: ");     String expression = keyboard.nextLine();      int result = evaluateExpression(expression);      System.out.println(result); }


unable to enable wifi in Ubuntu 18.04 on HP Pavilion

I installed Ubuntu 20.04 LTS along side windows 10. Everything seams fine apart from this wifi problem I'm having. The only way I can get an internet connection is through an Ethernet cable, because when I go to try and connect to a wifi network wirelessly i'm not getting the wireless option to connect. output of lspci -knn | grep Net -A3; rfkill list abhinavk@abhinavk-HP-Pavilion-15-Notebook-PC:~/Desktop$ lspci -nnk | grep 0280 -A3 08:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM43142 802.11b/g/n [14e4:4365] (rev 01)     DeviceName: Broadcom BCM43142 802.11bgn 1x1 WiFi Adapter + BT 4.0 combo adapter     Subsystem: Hewlett-Packard Company BCM43142 802.11b/g/n [103c:2230]     Kernel modules: wl abhinavk@abhinavk-HP-Pavilion-15-Notebook-PC:~/Desktop$ rfkill list all 1: hci0: Bluetooth     Soft blocked: no     Hard blocked: no  output on command : screenfetch                           ./+o+-       abhinavk@abhinavk-HP-Pavilion-15-Notebook-PC                   yyyyy- -yyyyyy+      OS: Ubuntu 20.04 focal                ://+//////-yyyyyyo      Kernel: x86_64 Linux 5.4.0-39-generic            .++ .:/++++++/-.+sss/`      Uptime: 1h 20m          .:++o:  /++++++++/:--:/-      Packages: 1720         o:+o+:++.`..```.-/oo+++++/     Shell: bash 5.0.16        .:+o:+o/.          `+sssoo+/    Resolution: 1366x768   .++/+:+oo+o:`             /sssooo.   DE: GNOME 3.36.2  /+++//+:`oo+o               /::--:.   WM: Mutter  \+/+o+++`o++o               ++////.   WM Theme: Adwaita   .++.o+++oo+:`             /dddhhh.   GTK Theme: Yaru-light [GTK2/3]        .+.o+oo:.          `oddhhhh+    Icon Theme: Yaru         \+.++o+o``-````.:ohdhhhhh+     Font: Ubuntu 11          `:o+++ `ohhhhhhhhyo++os:      Disk: 8.3G / 142G (7%)            .o:`.syhhhhhhh/.oo++o`      CPU: Intel Core i5-4210U @ 4x 2.7GHz [56.0°C]                /osyyyyyyo++ooo+++/     GPU: GeForce 830M                    ````` +oo+++o\:     RAM: 2506MiB / 3865MiB                           `oo++.


What would the correct way to add a conditional propertyCondition in an EntityFieldQuery

Please consider the following EntityFieldQuery. I would like to add a conditional parameter depending on the user's permissions. I'd expect the query would combine these statements and return both visibilities. However it ends in an empty result set. (Removing one of the statements gives the expected result).  $query = new EntityFieldQuery(); ... if(user_access('access public')) {   $query->propertyCondition( 'visibility', 'public' ); } if(user_access('access private')) {   $query->propertyCondition( 'visibility', 'private' ); } ...   So how could I make both conditions apply without blocking each other?


Lost windows while dual boot with ubuntu

I have genuine windows 10 in my lappy. I tried to dual boot with Ubuntu but accidentally I replaced my windows with ubuntu. So now I have only ubuntu in my pc and I lost my genuine windows. How to get back my windows OS.I dont even have my back up image of my windows


Are there evolutionary theories as to why we (and most animals) sleep?  Some claimed functions of sleep include: restoration, waste clearance, memory processing, etc. But unless we understand why these functions are necessary (in the sense that the cost outweigh the benefits in terms of evolutionary fitness) and why they cannot be accomplished awake, we won't have a clear evolutionary theory of sleep.  Are there current theories on the evolution of sleep?


Please verify my epsilon - delta proof $\lim_{x\to 2}(x^3 )=8,$ and $0 < x < 4$

I am concern about the delta calculation given $0 < x < 4$. I believe it works, but I am not 100 percent sure as I am new to proofs.  Consider the function $f(x) = x^3$ for $x ∈ ℝ$ and $0 < x < 4$. Prove that $$\lim _{ x\rightarrow 2 }{ { x }^{ 3 }=8 } $$  Proof: Let $\varepsilon  > 0$ be given, then let $\delta =  \min   {(\varepsilon/19,1)}$. Now suppose $|x -2| < \delta = \min {(\varepsilon /19,1)}$. Then $|x^3 - 8| = |x - 2||x^2 + 2x + 4|< |x - 2|<19$  $(|x^2 + 2x + 4| < 19~\text{if}~|x - 2| < 1)< \varepsilon /19 $  $(|x - 2| < \varepsilon /19 )= \varepsilon $.  Thus this $\delta$ makes $|x^3 - 8| < \varepsilon $ whenever $0 < |x - 2| < \delta$. Therefore, it follows that $\lim _{ x\rightarrow 2 } x^3 = 8$.


I installed fingerprint GUI in my laptop having Ubuntu 18.04.   But I am not able to login using fingerprint while in terminal using sudo commands it is working fine but for login it is not working.


Generating same information between multiple tabs in a spread sheet

I have an Excel document that has 4 tabs in it.  How do I formulate cells in each of the tab spreadsheets to generate the same if I change the information on one.  Example:  Each tab spreadsheet has a cell that I input the employee's drivers license number.  if I update on one of the tab spreadsheet, I want it to update then on the other three tab spreadsheets.


Is it possible to update any iOS 6 device to iOS 6.1.6?

Apple have just released software updates to fix  where a valid SSL response wasn't checked properly to ensure it matches the site actually being browsed. I have an iPhone 5, but unfortunately I have a strong personal aversion to the iOS 7 look and feel, so this far I've kept it on iOS 6.1.3.  Other users have better reasons than I to stay on iOS 6. For example, some people might be reliant on an app that has no iOS 7 version (as per bmike's comment), or the device might not have enough memory for the upgrade (as in this ).  Apple have released  ("Available for: iPhone 3GS, iPod touch (4th generation)"), but my iPhone 5 gives me no option to upgrade to any iOS other than 7.0.6. Similarly, iPhone 4 and iPhone 4S, iPad 2, [new] iPad (3rd gen), iPad Mini and iPod Touch (5th Gen)  but do not have builds of iOS 6.1.6 to install.   My iPhone is not currently jailbroken, but I would consider doing so in order to avoid having to use the iOS 7 interface. I'd rather not have to choose between the iOS version I prefer and this security patch for SSL. What options are feasible?


ubuntu 16.04 upgrade - two finger scroll not working

Some months ago I did a Ubuntu 14.04 to 16.04 upgrade on my Dell Inspiron - 5000 series.  After performing the upgrade I noticed the two finger scroll is not working any more. The option in the settings menu is available and active but the two finger scroll does not work. The other mouse functions on the touchpad work though. Previous questions on this forum did not result in a solution.  Does somebody has some experience concerning this matter? I would love to use my two finger scroll again  thanks  output of xinput terminal command:  ⎡ Virtual core pointer                      id=2    [master pointer  (3)] ⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)] ⎜   ↳ DLLC6AD:00 06CB:75BF Touchpad             id=11   [slave  pointer  (2)] ⎜   ↳ PS/2 Synaptics TouchPad                   id=13   [slave  pointer  (2)] ⎣ Virtual core keyboard                     id=3    [master keyboard (2)]     ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]     ↳ Power Button                              id=6    [slave  keyboard (3)]     ↳ Video Bus                                 id=7    [slave  keyboard (3)]     ↳ Power Button                              id=8    [slave  keyboard (3)]     ↳ Sleep Button                              id=9    [slave  keyboard (3)]     ↳ Integrated_Webcam_HD                      id=10   [slave  keyboard (3)]     ↳ AT Translated Set 2 keyboard              id=12   [slave  keyboard (3)]     ↳ Dell WMI hotkeys                          id=14   [slave  keyboard (3)]     ↳ DELL Wireless hotkeys                     id=15   [slave  keyboard (3)]


5% are left or 5% is left; which is better or correct?

So here is the sentence written both ways. Which one is correct and maybe a description why so I can understand why. Thanks! /R  Leatherbacks need your help. They’re endangered and only 5% of the population are left.  OR,  Leatherbacks need your help. They’re endangered and only 5% of the population is left.


Separate and Store File Content in Shell Script

Need to Separate the contents of a file using shell script and store them in diff variables and then invoke Jar using those variables. E.g  _ File Conent as below 122,aaakkw 333,3232is 1222,jsjsjs  Need to separate those variables delimited by , and store them in variables and pass them into my script in a loop


I saw , and I wondered what is inside it.  Has anyone seen this door? What exactly could be behind the mysterious door?!  I tried opening it but couldn't. Even tried lighting up the mushrooms with different sequences.  Perhaps it is supposed to open in the second play through?  Or maybe, you need to buy the key from those 2 girls [Bratty and Catty] who were selling trash?     Seeing the tag of Undertale, fills me with determination.


Let $T : [0, 1]^2 → [0, 1]$. Consider the following properties:  $T_1 : T(x, 1) = x$  $T_2 : T(x, y) = T (y, x) $  $T_3 : T(x, T (y, z)) = T(T (x, y), z) $  $T_4 $: If  $x ≤ u  , y ≤ v \Rightarrow T(x, y) ≤ T(u, v) $  Function $T: [0, 1]^2 → [0, 1]$ that satisfies $T_1 −T_4$ is T-norm.  consider $$T_L(x,y) = max(x+y-1,0) $$ we can show that $T_L(x,y)$ is a T norm.  Conditions 1, 2 and 4 are obviously. Can you help me to prove condition 3?


How to determine what command is being run from a menu icon?

I sometimes run into an issue where I try to run an app from the GNOME menu and nothing happens - the app name appears in the upper left and the spinny cursor comes up for a bit, but the application never launches. I want to try to troubleshoot what is happening by running the same command, whatever it is, from the command line, to see what the output is.  But I don't know what command is being run.  If I right click on the icon in the menu, I see a "Show Details" option. But it doesn't work the way I expect - it takes me to the software center, which sometimes isn't even right because it's not there.  But in no case does it actually give me a clue as to what the command line is that it is invoking. Where can I find this information? update: I found a related question which got me the information - I found that "menulibre" was already installed by default.  It didn't solve my initial problem though, because the command ran find from the command line.


The title question is rather illustrative. I suppose the real question would be:  Is heat cumulative?  Put back into an example:   If I have a lit candle right beneath an iron bar, assuming the candle will remain lit indefinitely, and that the heat-losing rate is below the heat-getting rate. Will the bar eventually reach the needed temperature for it to melt?  If the answer is no:  Once the iron bar reached the max temp the candle can get it to. Where does all of the energy (heat) go after?  EDIT:   The question "is heat cumulative?" can be ignored as it is out of place and is misleading. Althrough the answer for it is "yes", it doesn't mean the answer for the general question is also "yes".  The point is not if it is actually possible to melt iron with a candle. Iron and candle are mere parts of the illustration, their properties are irrelevant.  A better phrasing of the main question would be:  Could a heating object contained in a perfectly closed system push the temperature of the system above its own temperature?


Wrong dates in comments in Triage review

I see wrong dates for comments in the Triage review queue. The  is asked 29 minutes ago (today), but the comments are dated 24 May.


I want to define a new command using the package tikz-cd.  For example, suppose I want to define:  \newcommand{\simplearrow}[3]{\begin{tikzcd}  #1\arrrow[r, "#3"'] & #2 \end{tikzcd}}   This would give an arrow #3 from #1 to #2, but it does not work.  I guess the problem has to do with the double quotes in "#3" ' (the extra ' is for positioning the label below the arrow so it is important).   How to solve this?  Thanks


$A=\{(p,H): H\supset T_pX \}\subset X \times (\mathbb{P}^N)^*$ is irreducible!

Given a variety $X$ in a projective space $\mathbb{P}^N$, $dim X=k$.  Let $A=\{(p,H): H\supset T_pX \}\subset X \times (\mathbb{P}^N)^*$.   Objective: to show that $A$ is irreducible.   Idea, way:  (1) The fibers of $\pi_1:A \longrightarrow X$ are isomorphic to $\mathbb{P}^{N-k-1}$.   (2) Item (1) implies that $A$ is irreducible.   Why is item (1) true and why does it imply that A is irreducible?


Shared File Systems between multiple AWS EC2 instances

I have a couple of windows server instances running on Amazon EC2 and would like to make them a bit more fault tolerant by running a duplicate instance with load balancers.  The problem is the specific data, as an example it does no good to fail over from one web server to another web server if the contents of the document root i.e. C:/htdocs/ (Apache) or C:/Repositories (VisualSvn Server) are not identical.  Is there a way to share a volume across two or more instances?  My idea is share folder between EC2 istances:    read it's not possible to attach the same EBS volume to multiple instances. I believe also AWS is not NFS friendly either in case I want to mount them across NFS.  And finally, I've also checked S3 bucket mounted with s3fs but I found out it's not a good option too.  Can anyone help point me in the right direction?


Access to the off-topic sub-dialog again after voting to close

When I vote to close a question as off-topic vote, I often copy the text of the close reason from the close vote dialog to post as a comment to explain to the asker why the question is off-topic.    Unfortunately, unless I want to visit another question page, I have to do this before I actually cast the close vote, because once the vote has been cast, the dialog for the “close (n)” link doesn't allow me to get back into the off-topic subreasons.  To get the text for a comment, I have to open another question that I haven't voted on, open the close dialog, and copy from there.  This also means that I can't (if I wanted to), check on the specific off-topic reason that I voted for.  I'd like to be able to get back into the off-topic submenu after I've voted to close.  This obviously isn't a huge priority, but it would make my “workflow” a little bit easier for those times that I forget to copy the text first.


How does Thanos do this using Nebula's beacon?

In Avengers: Endgame, how does Thanos travel to the future using Nebula's beacon?  Does he have people experienced in quantum physics or some magic stone/equipment which can enable time travel of such a large scale army?