Molecules are the result of covalent bonds forming between atoms. Which of the four fundamental forces is responsible for covalent bonding? (Sorry if this is basic -- I'm guessing electromagnetic, but just wanted to check.)

This is not a duplicate, I am not asking why covalent bonds form or how they form. I am asking whether the covalent bond itself can or cannot be classified as a EM interaction (or if it is caused by a EM interaction)  I have read these questions:        Where Ben Crowell says in a comment:          It doesn't create any electrical interaction. In a covalent bond, each atom is still neutral.        Where Gert says:          To the right is also schematised the electron probability density ψ2 and note that this density is very significant on the nuclear axis, between both nuclei. This causes the intra-nuclear Coulombic repulsion force to greatly reduce and the molecular arrangement to be stable, meaning that pulling it apart would cost energy.        Where Manishearth says:          For covalent bonds, we have something known as electronegativity.      Now one says it has nothing to do with EM interactions, and the other ones say it is due to electronegativity, and the fact that intra-nuclear Coulombic repulsion forces greatly reduce when a covalent bond (a common molecular orbital) is formed.   This is a contradiction, both cannot be right. Covalent bonds must have a real reason to form and this can or cannot be electromagnetic, electrostatic, or be because of electronegativity. Or it could just be a non-electromagnetic cause, like a QM phenomenon. Anyway, there has to be a clear answer whether covalent bonds are classified as (and caused by) EM interactions or not.  Question:   Are covalent bonds classified as EM interactions or electrostatic interactions or a effect of electronegativity? Or are they just a QM phenomenon that we cannot classify (and explain) in terms of electromagnetics?


I have tried using the ratio lemma to tackle this question and also the fact $(n+1)^k \geq 1 + nk$ and I haven't reached an answer. How should I go about solving this problem?

In other words, how to prove:  For all real constants $a$ and $b$ such that $a > 1$, $$\lim_{n\to\infty}\frac{n^b}{a^n} = 0$$  I know the definition of limit but I feel that it's not enough to prove this theorem.


For any real numbers $a$ and $b$ and $1 \leq p < \infty$, prove that   $$|a+b|^p \leq 2^p \{ |a|^p +|b|^p \}$$  This inequality is given in the the book Real Analysis by Royden, Chapter $7$, page $136$. I don't understand how the author comes to this inequality. Can anyone provide some hints?

Assume that you have any two real numbers $a$ and $b$, and $1\leq k <\infty$, $k \in \mathbb{R}$.  How would you prove the inequality $|a+b|^k \leq 2^{k-1} (|a|^k+|b|^k)$?


I am new to Debian and I want to install the NVIDIA CUDA toolkit,  so I typed:  apt install nvidia-cuda-toolkit   but it did not work, I found out I need to add a source in /etc/apt/sources.list which contains this CUDA package.  However, as for now there are only a few lines in /etc/apt/sources.list referring to a university, which I chose during installation.  I do not know how to find out which source I need to add.  Is there a Debian database, where I can submit the program I need and which in turn gives me a list of sources containing it?

How to install  or 8 on Debian 8?  I know that Debian 8 comes with the option to  using apt-get install nvidia-cuda-toolkit, but how do you do this for CUDA toolkit version 7.0 or 8?  I tried installing using the Ubuntu installers, as described below:  sudo wget http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1404/x86_64/cuda-repo-ubuntu1404_7.0-28_amd64.deb  dpkg -i cuda-repo-ubuntu1404_7.0-28_amd64.deb  sudo apt-get update  sudo apt-get install -y cuda   However it did not work and the following message was returned:  Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  cuda : Depends: cuda-7-0 (= 7.0-28) but it is not going to be installed E: Unable to correct problems, you have held broken packages.


Attempted to add to this question: , however wasn't able to.   After installing nvm im having the same issue, here is the log from terminal:  Michael-iMac:~ michaels_imac$ curl https://raw.github.com/creationix/nvm/master/install.sh | sh   % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current                                  Dload  Upload   Total   Spent    Left  Speed 100  1202  100  1202    0     0   5759      0 --:--:-- --:--:-- --:--:--  6829 => NVM is already installed in /Users/michaels_imac/.nvm, trying to update =>   Already up-to-date.  Michaels-iMac:~ michaels_imac$ nvm install 0.8  -bash: nvm: command not found

I am trying to install  and followed the installation instructions provided at its Github page.  Installation got over but now I am getting an error as command not found: nvm when I try using nvm install 0.8  Can someone please help me find out why I am gettting an error that nvm is not found when I have already installed it.


Are there english words for a person who sincerely thinks of him as an expert but in reality (by common standards) is not?  Source: Recently, in my native place, a very popular movie actor (let us say his name is extrem) started a music band and held a live show during a government sponsored program which was widely criticized and made fun of. Nowadays, if someone claims to be something he is not, the media refers to it as extremism jokingly.

If someone thinks they are always doing the right thing, and believes others are wrong, what would I call them?  Say, for example, I did something that person considers wrong. But then on another occasion, the same person does the same thing I did and believes they are right. So they feel like they're an exception, but at the same time, others are wrong and can't act like that.


It's hard to imagine a pine tree wishing it was an oak. It's hard to imagine a pine tree wishing it were an oak. Which is correct sentence?

Possible Duplicate:          Is this correct grammar?     What if there was a Stack Overflow on…    Shouldn't it be "what if there were a Stack Overflow on…"?


Apologies if this is not the correct platform for asking this. I recently got my question down voted, now under normal circumstances a developer would not just post a question unless they think they have exhausted all the other resources like asking co-developers(mostly seniors of course). My question was down voted but that person did not bother to maybe add a comment to say why.  I was wondering if is there perhaps a way of forcing someone to at least leave a comment after a down vote, I understand a down vote means the voter thinks a question is not well put or no enough research was done prior to the question being asked so at least a person should be able to leave a comment maybe a link that points to an answer to that very same question(especially the one answered on the very same stack overflow site), that why I can see how lazy or stupid I am for not seeing an answer that is right under my nose.

Note: If you're looking for a simple explanation as to why comments aren't required on downvotes, see .   I used to get "upset" (though that is too strong a term) when I got downvoted without comment. If my answer isn't good enough then I'd like to know why. Not only does it improve the answer for the OP but it improves my knowledge too.  Where the down-vote has been explained I've found it useful & it has improved my answer, or forced me to delete the answer if it was totally wrong.  So is there any way we can encourage people to leave a comment? Perhaps they don't lose rep if they explain their down-vote?  I must admit though that I haven't always explained my down-vote either so you could call me a hypocrite. I've also grown a thicker skin over the months of using SO (it seems to have come with the higher rep score ;-)), so I'm less bothered about this now.


When to use the former and when to use the later? And why?  Example:  You never eat the bell peppers of your lunch boxes.  You never eat the bell peppers in your lunch boxes.

I'm not a native speaker, and the uses of prepositions are driving me crazy.  I saw a post with the phrase "you are the champion of my heart" on it. I thought it should be "the champion in my heart", "of my heart" sounds like you have several hearts, and one of them is your champion... Then I googled it, found out this "of my hearts" usage got more results than "in". The same question goes for "Secret of my heart" and "secret in my heart".  I read some grammar books, there were a lot of examples for prepositions, but still cannot cover all of the situations. Are there any rules about how to use prepositions correctly or I just have to remember every case I've met?  Thank you.


A question straight from the football commentary pages :      X's shot deflected off of Y before finding its way into the net.   What is the correct usage here ?  Deflected off of or deflected off ??  Or, are both usages correct?

How can I explain to people that the phrase off of is grammatically incorrect?  I‘ve heard this phrase used a lot, especially by Americans (though they aren't the only ones).    In my understanding, off of should usually be replaced by off, as in,     I took the book off the shelf   as opposed to     I took the book off of the shelf   Am I wrong?  Or is there perhaps some simple way I can explain this to most people?


I have a set observations of the same distribution with an unknown parameter. My statistics textbook says for two instances of the parameters, called $\phi_1$ and $\phi_2$, $\phi_1$ is more plausible value to be the true parameter than $\phi_2$ if $p(X = x | \phi_1) > p(X = x | \phi_2)$. I have no trouble to interpret the comparison of two probabilities of a random variable, for example p(X = a) < p(X = b) because I can rely on counting on the sample space of X to make sense the comparison. From my point of view conditional probability of different conditions are computed from different (sub) sample spaces so relying on counting to interpret does not work. How do you justify the comparison of the two conditional probabilities?

After taking a statistics course and then trying to help fellow students, I noticed one subject that inspires much head-desk banging is interpreting the results of statistical hypothesis tests.  It seems that students easily learn how to perform the calculations required by a given test but get hung up on interpreting the results.  Many computerized tools report test results in terms of "p values" or "t values".  How would you explain the following points to college students taking their first course in statistics:   What does a "p-value" mean in relation to the hypothesis being tested?  Are there cases when one should be looking for a high p-value or a low p-value? What is the relationship between a p-value and a t-value?


How would you reference an issue that is of little meaning but takes lots of attention for no apparent reason than just being the only thing that is interesting?  I've researched some words such as    Petty Fight Bun Fight   Yet I don't feel these dwell well enough with the word I'm looking for.

The recent EL&U question asked by Mikhail about the alternative expressions of ‘To shoot out of cannon into sparrows’ reminded me of Japanese saying - 大山鳴動鼠一匹- literally meaning people find (get) “Only a small mouse coming out after hearing rumblings and experiencing shaking of the big mountain, (and jumping out of the house)” which I believe was imported from Chinese classic literature.   I think it has a different meaning from “Shoot sparrows with cannon” and “Chop a chicken using the blade for cow.” Instead it means “a very small result attained with great effort” or “marginal consequence or gain after making a big fuss”  Are there similar English sayings to express “大山鳴動鼠一匹 - Big fuss, tiny result”?


Consider:  $ find . -name *.css ./style.css ./view/css/style.css  $ ls view/css/ consultation.css  jquery.scombobox.min.css  page-content.css  style.css   Why might find have missed the files in view/css? This is on Ubuntu 15.10, an obscure Debian derivative.

Using find with grep, one can locate files that match a pattern:  # find | grep error ./solr-modifiedSolr4/SolrPhpClient/phpdocs/errors.html ./error_log ./includes/classes/error_log   However, using find alone the first file is not found:  # find . -name error* ./error_log ./includes/classes/error_log   Why doesn't find locate the errors.html file when not used with grep? How is find used to show this file as well?


How to calculate following integration?  $$\int\left( \sqrt{\tan x}+\sqrt{\cot x}\right)dx$$

Which is the easiest way to evaluate $\int \limits_{0}^{\pi/2} (\sqrt{\tan x} +\sqrt{\cot x})$?   I have reduced this problem to $$   2\int_0^{\pi/2} \sqrt{\tan x} \ dx$$  but now, evaluating this integral is giving me some problems, simply substituting $u=\tan(x)$ and then $\mathrm{d}u=\sec^2(x)\mathrm{d}x \Rightarrow \frac{\mathrm{d}u}{1+u^2}=\mathrm{d}x$ and which in turn gives something a bit ugly, I was wondering which is the most elegant way to evaluate this?


This question actually arises from  to another question, which contains the sentence     A function is smooth is it has derivatives of infinite order.   While the author surely didn't actually mean $\frac{\mathrm d^\infty f}{\mathrm dx^\infty}$, a comment on that post got me to think about that.  I've come to the following definition:  Be $\alpha$ an arbitrary ordinal. Then the $\alpha$th derivative of $f(x)$ is defined as follows, provided the used derivatives/limits exist: $$\frac{\mathrm d^\alpha f}{\mathrm dx^\alpha} = \begin{cases} f & \text{if }\alpha = 0\\ \frac{d}{dx}\,\frac{\mathrm d^\beta f}{\mathrm dx^\beta} & \text{if } \alpha=\beta+1\\ \lim_{\beta\to\alpha}\frac{\mathrm d^\beta f}{\mathrm dx^\beta} & \text{if } \alpha \text{ is a limit ordinal} \end{cases}$$ Here the limit is meant pointwise.  Here are a few cases:   If $f(x)$ is an arbitrary polynomial, $\frac{\mathrm d^\omega f}{\mathrm dx^\omega}=0$. If $f(x) = \exp(a x)$, then $$\frac{\mathrm d^\omega f}{\mathrm dx^\omega}= \begin{cases} 0 & \text{if } -1 \le a < 1\\ \exp(x) & \text{if } a = 1\\ \text{does not exist} & \text{otherwise} \end{cases}$$ $\sin(x)$ and $\cos(x)$ don't have a $\omega$th derivative.   Also the $C^n$ classes can be generalized in a straightforward way: A function is in $\tilde C^\alpha$ if for every $\beta\in\alpha$, the $\beta$th derivative of $f$ exists and is continuous. For finite $n$, we have $C^n=\tilde C^{n+1}$ ($\tilde C^0$ would be all functions). Moreover, $C^\infty = \tilde C^\omega$. If the $\omega$th derivative exists and is continuous, the function is in $\tilde C^{\omega+1}$.  Now my questions:   Has anyone already considered such derivatives? Are they even useful somewhere? Is there an easy way to characterize the functions in $\tilde C^{\omega+1}$? Are there functions in $\tilde C^{\omega+1}$ whose $\omega$th derivative is neither $0$ nor $\exp(x)$? (Otherwise the ordinal order derivatives would be rather boring).

Let $f:A\rightarrow A$ be a function. We can simply define $f\circ f$, $f\circ f\circ f$, etc., for each given natural number inductively.   $f^{(0)}=id_A$  $\forall n\in\omega \qquad f^{(n+1)}=f\circ f^{(n)}$  How to define $f^{(\omega)}$ such that it be a function from $A$ to $A$? Is it possible to define $f^{(\alpha)}$ for arbitrary large ordinal number $\alpha$?


Both partitions, with the windows and the other one were formatted and merged into one not unpartitioned space. Is there a way to recover the data with some bootable program or should I install the operating system first and then some software for recovering?  Is installing the OS going to overwrite data?    How can I access and get those 16.91GB of data?

What steps can I take to try to recover lost or inaccessible data from any storage device?  Answers:   This applies to any computer storage device, e.g. internal/external hard drives, USB sticks, flash memory. The most important thing is to STOP using it, any type of I/O can ruin your chances of a recovery.     We have separate questions covering common problems with USB flash drives in greater detail:


I need to find all complex numbers $z$ such that $\mid 2z/(z^2+1) \mid < 1$. If $z$ were real, it would be easy, but now that $z$ being complex numbers makes things so twisted...I cannot find a way to approach. Could anyone please help me?

We have a complex plane and there are inequality on it: $2|z| > |1 + z^2|$. What is the locus of such set of $z$?  I tried to solve it by using polar coordinates and got: $r^4 - 2r^2\cos(2\phi ) - 1 = 0$.  As well I tried solve it using $z = x + iy$ and got: $4(x^2 + y^2) = (x^2 - y^2 + 1)^2 + 4x^2y^2$  By I still can`t figure out what is the explicit name or at least descritpion for such locus of points. Will be very grateful for any help.


I have this code in C#  double result = 480 - 460.8;   Why result is 19.199999999999989 instead of 19.2?

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


Is there a direct way to find out if the bootloader on a new unrooted device is currently locked or not? I would like to do this without the risk of clearing or bricking the device. I am looking for some command in adb or fastboot that will just provide this information.  The reason I ask this, is because all my rooting attempts have failed so far. I suspect a locked bootloader.

I'm about to flash a custom recovery, but I'm not sure if my bootloader is unlocked or not (phone is rooted, but I did it a while ago, so I can't remember the process I went with), and I don't want to do anything that might risk losing all my current data. Can I simply run fastboot flash recovery [recovery image], and if it doesn't work, take that to mean my bootloader is locked? Are there any negative consequences to attempting this with a locked bootloader?


Can somebody explain me how to use Holder's inequality and Minkowski's inequality. Can these inequalities be used to solve the problem that if $x, y, k$ are non negative  reals then prove that  $$\left(1+\frac{x}{y}\right)^k +\left(1+ \frac{y}{x}\right)^k \ge 2^{k+1}$$ Edit 1- My main question is about what Holder's inequality and minkowski's inequality are and how do we use them

Let $a$ and $b$ be positive real numbers and let $n$ be a natural number prove that   $$\left({1+\frac ab}\right)^n+\left(1+\frac ba\right)^n\ge2^{n+1}.$$


I want to round this with 2 decimal places value in c#. Here is my code.  IList<CartModel> CartItems = (from c in db.tblCart                                               where c.User_ID == UID                                               && c.Is_Active == true                                               select new CartModel                                               {                                                   CartID = c.Cart_ID,                                                   UserID = (c.User_ID == null ? 0 : (int)c.User_ID),                                                   SellerID = (c.Seller_ID == null ? 0 : (int)c.Seller_ID),                                                   BuyerID = (c.Buyer_ID == null ? 0 : (int)c.Buyer_ID),                                                   Quantiy = (c.Quantity == null ? 0 : (int)c.Quantity),                                                   Price = (c.Price == null ? 0 :((float)((c.Price*ConversionRate) * c.Quantity))),                                                   Match = (c.Match == null ? 0 : (int)c.Match),                                                                                }).ToList();                 return CartItems;  Price = (c.Price == null ? 0 :((float)((c.Price*ConversionRate) * c.Quantity))) How to apply math.round function on this? Price datatype is float.

I want to do this using the Math.Round function


I've got this piece of code:       if (self::$username == "Borsucza Łapa.") {         die("tak");       } else {         echo self::$username . "<br />";         echo "Borsucza Łapa.";       }  The condition is not valid, and the output from else statement is: Borsucza Łapa. Borsucza �apa.  What's that sign and how to turn it to an Ł sign?

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.  Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?  This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.


I was running some queries just to test the site and the returns do not seem to reflect my activity at all. E.g.,  query tells me that I have 2 answers on SO, with one scored and one unscored. Same with other queries. I'm using my SO user id on the box (542701). Am I doing something else wrong? BTW, I hesitated to post this question here (I don't know if it's on-topic), but data.SE does not have any commenting options and there are other questions related to data.SE here.

promised that data.SE would "soon" get live data:     I realize it's a long weekend, but given that data.SE is now over 2 months out of date, it would be nice if this was finally rolled out.


I am currently transferring a folder to a USB drive. For the last few minutes, it has quite literally been transferring at LESS THAN 1 kb/s... we're talking 10-500 bytes/s..  How is it possible for anything to transfer this slowly and how can it be fixed?

I noticed that if I transfer a few large files between two hard drives, it's pretty speedy, at around at least 30 MB per second, but if I transfer thousands of files less than 5 KB, it is pretty damn too slow.. around 1 to 2 MB per second.   Is there a way to speed up the copy/paste process with thousands of small files on Windows 7?


As a math-for-fun exercise, I've recently been seeking bounds for the error $R_k$ made when using $\sum_{n=1}^{k}\frac{1}{n^2}$ to estimate its beautiful sum $\frac{\pi^2}{6}$. Applying the Comparison Test for series multiple times, I derived the following estimates: $$\frac{1}{k+1}<\frac{\pi\coth(\pi)-1}{2}-\sum_{n=1}^{k}\frac{1}{n^2+1}<R_k<\ln\left(1+\frac{1}{k}\right)<\frac{1}{2k+2}+\frac{1}{2k}$$ The lower estimate $\frac{\pi\coth(\pi)-1}{2}-\sum_{n=1}^{k}\frac{1}{n^2+1}<R_k$, which I derived with WolframAlpha's help, is pretty useless. $\frac{1}{k+1}<R_k$ is good, but I want to improve it. Given how clean and tight the upper estimate $R_k<\ln\left(1+\frac{1}{k}\right)$ is, I figured I could find a similar lower estimate that's just as clean and tight. After thinking for a while, I came up empty handed. I can't seem to find a positive sequence $a_n$ lying between $\frac{1}{n^2+1}$ and $\frac{1}{n^2}$ for which $\sum_{n=1}^{k}a_n$ has a clean expression. Any ideas or hints? Edit: I'm not trying to prove the convergence of $\sum_{n=1}^{\infty}\frac{1}{n^2}$ nor any other series.

Show that $$1+\frac {1}{4} \bigg(1+\frac {1}{4}\bigg) +\frac {1}{9} \bigg(1+\frac {1}{4} +\frac {1}{9}\bigg)+.....$$  converges.  Can you find the exact value of the sum.  My effort:  I have proved the convergence with comparing to $$\bigg(\sum _1^\infty \frac {1}{n^2}\bigg)^2$$  I have not figure out the exact sum.  Any suggestions??


\def is sometimes used as an abbreviation of a box construction, then its output is sometimes the same as the output with a \box register instead of \def.   Here is the question. When should I use a \box register rather than \def? Is there any specific situation one is better than the other one?    EDITED (09/12/09 UTC 2:45)  Edited question  Is there any cases that \setbox and its output commands pair (not only \box0, but also \copy0, \unhbox0, and so on)  can be replaced a macro definition which is eventually expanded as a box?  If there was such a case, is there any specific situation one is better than the other one?  Examples I thought  Case 1:  \def\excuse{I should have made my question more clearer before the post.} \setbox0=\hbox{I should have made my question more clearer before the post.}   I think the above case is the same as long as I call the box register with \unhcopy0. However, I wonder whether first one is better than second one because it can save memory.   Case2:  \def\excuse{\hbox{I should have made my question more clearer before the post.}} \setbox0=\hbox{I should have made my question more clearer before the post.}   I think the above case is also the same as long as I call the box register with \copy0.  Case3:  \def\myhrulefill{\line{\leaders\hrule\hfill}} \setbox0=\line{\leaders\hrule\hfill}   in this case, \hbox contains commands and which I suspected whether I can say those are the same or not.   Unfortunatelly, I cannot show you a sufficientlly complex example which contains some commands. Parhaps, if above examples contained conditional syntax like \if, repetion syntax like \loop...\repeat, one cannot be an alternative of the other one. I especially like to know such a case.

Despite my inflammatory title, I understand that \usebox is employed to display a predefined box.  But this question concerns when [the use of the box register, rather than the box content] becomes absolutely essential to a LaTeX operation (for example, as arguments to \wd, \ht, and \dp). [EDITS above and below in brackets, to reflect proper terminology]    Clarifying, based on Werner's comments, given the syntax  \newsavebox{\xyz} \sbox{\xyz}{...} \def\xyzbox{\usebox{\xyz}}   are there useful things I can perform only upon [the register] \xyz that I cannot perform on [the box content] \xyzbox?  (If not, then maybe \usebox is vestigial).    For example, consider the LaTeX syntax  \newsavebox{\xyz} \sbox{\xyz}{...} \usebox{\xyz}   Why couldn't LaTeX have been constructed so that the last line could have been issued as \xyz, without the \usebox (saving me a few characters of typing)?  I am so frustrated [an exaggeration] with the \usebox syntax, that I work around it in both the verbatimbox package and the \stackengine package. In the former, I allow this syntax:  \begin{myverbbox}[]{\boxname} ... \end{myverbbox} \boxname% <--NOTE: THIS IS NOT \usebox{\boxname}   Internally, \boxname actually points to \usebox{boxnamecontent}  Likewise, in stackengine, I allow:  \savestack{\mystack}{VARIOUS STACKING COMMANDS} \mystack% <---NOTE: THIS IS NOT \usebox{\mystack}   Internally, \mystack actually points to \usebox{\mystackcontent}  So the crux of my question is this?  When is the [use of a box register] essential to a LaTeX operation??  I realize things like \wd, \ht, and \dp act on the un-rendered box name itself (without the \usebox); however, even these are replaceable by calc's \widthof, \heightof, and \depthof, which act upon the (rendered) \usebox version of the box.  So what other TeX/LaTeX operations act upon [the box register, rather than the content]?  In essence (rhetorically), why do we still need \usebox syntax if everything that acts upon a box acts upon the rendered \usebox form of the box?  [So far, the answers have revealed that I need the box register to set the box, and to use the box.  And I can, but don't need to, use the register to measure the box.  And in nebulous places where I "need a number, not... a box".    Any other usages of the box register?]


i want to add li elements it´s work fine, but the remove dosen´t work for the new elements.  I had three li Elements at the start, for that the remove function work´s.  With my "add" Function i create the Li Elements with the same class, why it doesent work for the new one ?    $(document).ready(function(){     $("#add_li").click(function (){         $("ol").append("
" + $("input").val() + "X
");     });     $("#remove_li").click(function(){         $("li:last").remove();     });     $(".remove").click(function(){         $(this).parents('li').remove();     });      var log = $('.remove');     console.log(log);     console.log(jQuery);      });

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


Can you please refer a source that you consider to contain the most complete list of statements and theorems equivalent to the axiom of choice (over the axioms of ZF)?  I am already aware of most of the equivalent statements listed on the wiki page here:   I am most likely looking for a study or (maybe several) chapters of a book.

The Axiom of Choice reads:     The product of a collection of non-empty sets is non-empty.   As you know well, this axiom is equivalent to many other statements. A few examples (probably the most known) are the following:   Zorn's lemma: Let $(P,\ge)$ be a poset in which every chain has an upper bound. Then $P$ has a maximal element.   This is used in a number of different places to prove very powerful theorems. A couple of examples I can think of right now are: the proof that every ring has a maximal ideal (commutative algebra) and the  (functional analysis).   Well ordering theorem: Every set can be well-ordered (i.e. it admits a total order such that every subset has a least element). Tychonoff's theorem: Every product of compact topological spaces is compact.   This is used for example in the proof of  (again functional analysis).   gives various more. Among them:   Tarski's theorem: If $A$ is an infinite set, then there is a bijection $A\to A\times A$.   (As @Wicht dutifully commented, Tarski's theorem is the name given to the implication $|A|=A\times A \Rightarrow$ Axiom of Choice, while the other implication was known before the proof of this fact by Tarski.)   Every vector space has a basis.   My question is: what are other useful statements which are equivalent to the axiom of choice? Where are they used, and to prove what?  P.s.: By "useful statements" I mean either statements which are important theorems by themselves (as Tychonoff's theorem) or that are directly used in (simple versions of) the proof of important theorems (as Zorn's lemma).


I have had Ubuntu 18.04 LTS installed on my laptop for nearly 2 years and noted that startup has been getting slower over time.  Here is what I have done so far to improve startup time:   Cleared out the following locations (files only not directories): '/var/log' '/var/cache/apt/archives' At startup my screen started going blank for approx 40 secs,approx the same time as plymouth-quit-wait.service (splash) over time and incidentally for several months apport was reporting a _sbin_plymouthd.0.crash which appeared to eventually be fixed after a number of scheduled kernel updates, but after it was fixed the screen started going blank for approx 40 secs and kept occurring.  I had never modified the grub bootloader and so it has always been set to the defaults on startup.     [Edited] I removed the part about the grub bootloader settings since I found none of the grub options made any difference and in any case, I forgot to run update-grub afterwards so I was never changing anything and it was nothing to do with any grub options.    After some further testing the blank screen in (2) above is something I found I introduced myself while disabling and enabling specific services while trying to speed up my system, I had disabled the avahi service, but forgot to re-enable when I was done testing and if this is disabled at startup this appears to cause the screen to go blank for around 40 seconds.  As a result. of (1) above I have improved my startup time significantly and it is now:      ~$ systemd-analyze time  Startup finished in 3.912s (kernel) + 1min 25.875s (userspace) = 1min 29.788s graphical.target reached after 1min 23.660s in userspace  ~$ systemd-analyze critical-chain graphical.target @1min 23.660s └─multi-user.target @1min 23.660s   └─kerneloops.service @51.738s +127ms     └─network-online.target @51.722s       └─NetworkManager-wait-online.service @43.696s +8.024s         └─NetworkManager.service @36.659s +7.032s           └─dbus.service @32.763s             └─basic.target @32.644s               └─sockets.target @32.644s                 └─snapd.socket @32.642s +768us                   └─sysinit.target @32.527s                     └─apparmor.service @27.457s +5.007s                       └─local-fs.target @27.457s                         └─run-user-121.mount @49.661s                           └─local-fs-pre.target @6.087s                             └─systemd-tmpfiles-setup-dev.service @4.597s +1.489s                               └─kmod-static-nodes.service @4.466s +129ms                                 └─systemd-journald.socket @4.465s                                   └─system.slice @4.465s                                     └─-.slice @4.436s  ~$ systemd-analyze blame |head -10  39.898s plymouth-quit-wait.service  21.404s dev-sda2.device  17.689s systemd-journal-flush.service  13.880s snapd.service  10.733s networkd-dispatcher.service  9.775s ModemManager.service  8.560s dev-loop10.device  8.426s dev-loop18.device  8.101s dev-loop15.device  8.064s udisks2.service   Having migrated from Windows which doesn't automatically clean up temp files and app cache and therefore the following slow Windows down with the size increase over time:    Temporary/archived files App Cache. Profile size.

So I have looked at a lot of suggestions from this website already and tried quite a few of them, but they all differ and I get a feeling these are very specific problems for which I lack the expertise to find which exact case applies to me.  Here is my result for systemd-analyze blame  1min 59.160s plymouth-quit-wait.service      33.950s apt-daily.service       7.276s NetworkManager-wait-online.service       2.292s apt-daily-upgrade.service        754ms fwupd.service        397ms dev-sda6.device        375ms systemd-logind.service        362ms plymouth-start.service        230ms NetworkManager.service        209ms udisks2.service        169ms networkd-dispatcher.service        160ms systemd-timesyncd.service        147ms systemd-resolved.service        135ms ModemManager.service        123ms apparmor.service        104ms accounts-daemon.service        100ms keyboard-setup.service         99ms systemd-journal-flush.service         91ms systemd-udevd.service         75ms upower.service         71ms systemd-udev-trigger.service         69ms plymouth-read-write.service         62ms systemd-rfkill.service   And this is what I get from systemd-analyze critical-chain:  graphical.target @2min 330ms └─multi-user.target @2min 330ms   └─kerneloops.service @8.446s +7ms     └─network-online.target @8.441s       └─NetworkManager-wait-online.service @1.164s +7.276s         └─NetworkManager.service @932ms +230ms           └─dbus.service @877ms             └─basic.target @872ms               └─sockets.target @872ms                 └─uuidd.socket @872ms                   └─sysinit.target @868ms                     └─systemd-timesyncd.service @707ms +160ms                       └─systemd-tmpfiles-setup.service @672ms +31ms                         └─local-fs.target @671ms                           └─run-user-122.mount @1.340s                             └─swap.target @623ms                               └─dev-disk-by\x2duuid-19af8e87\x2d864e\x2d4148\x2d                                 └─dev-disk-by\x2duuid-19af8e87\x2d864e\x2d4148\x   These were a few things I noticed  were added to most of these questions, so I thought they might help as well.   I run ubuntu 18.04 LTS in a dual boot configuration using GRUB. My grub version is 2.02-2ubuntu8.9.


I started my Ubuntu 15.10 and am unable to open the software updater app. I keep getting the following error  SystemError: E:Malformed line 55 in source list /etc/apt/sources.list (dist parse)   I tried purging the app and reinstalling, but still get the same error. Any suggestions?

I have unistalled and reinstalled the Ubuntu Software Center as per info I found in a similar thread and I got the same response about line 91 or something like that.  I just tried to upload a screen shot but since I'm new it won't allow me to.  I also can not figure out how to cut and paste anything so I have to hand type what the error screen says, both when I attempt to open the software center and nothing happens, when I try to enter commands into the terminal to uninstall, reinstall, whatever I get the same following:  COULD NOT INTITIALIZE THE PACKAGE INFORMATION An unresolvable problem occured while initializing the package information Please report t:his bug against the 'update-manager' package and include the following error message: 'E: Malformed line 91 in source list/etc/apt/sources.list (dist parse)  E: The list of sources could not be read.,  E: The package list of status file could not be parsed or opened.   How do I report bugs?  What can be done about this.  I have searched and everything everyone says to do leads me back to the same line error message.  So, I don't know how to get to line 91 in the source list; to tell you what it says. Sorry, I'm really new to this. That is what I need is to find out how to get there and fix what it says. I would really like to NOT have to re partition my hard drive and start from scratch, so I'm really looking forward to getting this problem solved. I need to be able to install new software.


I want to loop over a list of strings and construct different functions with each string. It looks like references to the string variable are being stored. So when I call each of the foo functions they each only use the last assignment to s. Is there a different way to achieve this?  los = ['hello', 'and', 'bye'] foos = [] for s in los:     k = s     def foo_():         print k     foos.append(foo_)  for i in foos:     i()   prints   bye bye bye

While I was investigating a problem I had with lexical closures in Javascript code, I came along this problem in Python:  flist = []  for i in xrange(3):     def func(x): return x * i     flist.append(func)  for f in flist:     print f(2)   Note that this example mindfully avoids lambda. It prints "4 4 4", which is surprising. I'd expect "0 2 4".   This equivalent Perl code does it right:  my @flist = ();  foreach my $i (0 .. 2) {     push(@flist, sub {$i * $_[0]}); }  foreach my $f (@flist) {     print $f->(2), "\n"; }   "0 2 4" is printed.  Can you please explain the difference ?    Update:   The problem is not with i being global. This displays the same behavior:  flist = []  def outer():     for i in xrange(3):         def inner(x): return x * i         flist.append(inner)  outer() #~ print i   # commented because it causes an error  for f in flist:     print f(2)   As the commented line shows, i is unknown at that point. Still, it prints "4 4 4".


I don't want to burn a CD, DVD or USB memory stick. And I don't care about saving the existing operating system (Linux Mint). I want to install Ubuntu (actually Kubuntu 12.04 LTS) to the computer directly from the ISO image. The image is for the Kubuntu Live DVD (3.5 GB).  The computer is now booted into Linux Mint. A set of command line steps would be satisfactory. In my mind, I simply need to trick the existing system into thinking I inserted a CD/DVD, right?  I know there is a similar question already but it does not have a good answer. The answer basically says, "see this link." I reviewed the link and I decided that StackExchange needs a good answer to this question. Furthermore, most answers at other places on the Internet assume the user is coming to Ubuntu from Windows. So I think this question is one that needs a good answer here. Thanks


As far as I know each down vote is supposed to reduce reputation by 1 ,but I have down voted some question and answers but my reputation hasn't changed. Is this a bug or I'm mistaken

On Stack Exchange, users may gain a certain level of reputation.  What does reputation do? How can a user gain or lose reputation?   See also   in the Help Center  - Maximum amount of votes a user can use in a day and reputation requirements to vote.  - How to get an exact overview of the actions that got you your reputation.  - A full list of all privileges granted at each reputation level on all sites.


I want to add an affiliate program to my website:  (recommend to use mobile to visit it) You will find that the site works normal, but now check out '' The error pop up!     Error: 'Warning: mysqli_stmt_bind_param(): Number of variables doesn't   match number of parameters in prepared statement' (on line 12)   mobile.php code:  <?php  session_start(); require_once "config.php"; $affiliate = "";  if ($_SERVER["REQUEST_METHOD"] == "GET") {     $affiliate = $_GET['affiliate'];     $sql = "SELECT id, affiliate, click, signup FROM users WHERE affiliate = $affiliate";     if ($stmt = mysqli_prepare($link, $sql)) {         // Bind variables to the prepared statement as parameters         mysqli_stmt_bind_param($stmt, "ssss", $param_id, $param_affiliate, $param_click, $param_signup);          // Set parameters         $param_affiliate = $affiliate;          // Attempt to execute the prepared statement         if (mysqli_stmt_execute($stmt)) {             // Store result             mysqli_stmt_store_result($stmt);              // Check if affiliate exists             if (mysqli_stmt_num_rows($stmt) == 1) {                 // Bind result variables                 mysqli_stmt_bind_result($stmt, $id, $affiliate, $click, $signup);                 mysqli_query("UPDATE users SET click = click + 1 WHERE affiliate = $affiliate");                 session_start();                  // Store data in session variables                 $_SESSION['affiliate'] = $affiliate;             }         }     } }   $_SESSION['affiliate'] is used to track the affiliate link. mysqli_query("UPDATE users SET click = click + 1 WHERE affiliate = $affiliate") is used to add 1 click when someone click the affiliate link.  How to solve the error?

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


So I have $$|a|=|(a-b)+b|\leq |a-b|+|b|\Rightarrow |a|-|b|\leq |a-b|$$ and $$|b|=|(b-a)+a|\leq |b-a|+|a|\Rightarrow |b|-|a|\leq |b-a|$$ now the next step in my book is listed as multiplying by $-1$ to get $$-|a-b|\leq |a|-|b|$$ Next they say that they combine these two inequalities now to get $||a|-|b||\leq |a-b|$. I can't seem to figure out the algebra they did to get this.


What I'm trying to achieve is a fixed width (full width of the page or column) table with variable column widths. Here's what I've got:  \usepackage{tabulary}     % Table Environment \newenvironment{dndcustomtable}[1]{   \vspace*{8pt}   \fontfamily{lmss}\selectfont %Select font   \rowcolors{1}{bgtan}{commentgreen} % Alternate colors   \noindent\tabulary{\textwidth}{#1} } {   \endtabulary   \vspace{8pt plus 1pt}   \noindent }  % Usage \begin{dndcustomtable}{LLL} lorem ipsum &   foo bar &   baz \\ lorem ipsum lorem ipsum &   foo bar &   baz \\ lorem ipsum &   foo bar &   baz \\ lorem ipsum &   foo bar lorem ipsum&    baz \\ \end{dndcustomtable}   What I'm getting:   Desired Result:   Any ideas?

With this MWE  \documentclass{article} \usepackage{tabulary}  \begin{document}  \hrule  \begin{center}   \begin{tabulary}{\textwidth}{|L|L|L|}     foo&bar&baz   \end{tabulary} \end{center}  \hrule  \end{document}   I get a table which is narrower than the page:   But I'd like the table to be spread out to \textwidth like tabularx would do. Is this possible?  Or is there an alternative approach?


I have something like this:   if (result.Indicator == 1) {     $('#IndicatorImgDiv').append($('<img />').attr("src", "/Content/images/reddot.png")); }   Now, this appends an image of a red dot when I click on a button but when I click on a button again, it appends it again. I just want it to appear once when I click on a button. How can I check if the appended element already exists or not?

How can I check the existence of an element in jQuery?  The current code that I have is this:  if ($(selector).length > 0) {     // Do something }   Is there a more elegant way to approach this? Perhaps a plugin or a function?


I'm currently working on a number of almost ethereal object, and I'd like them to emit a number of sparkly, glittery particles (almost like pixie dust, best example I can think of). I'd like them to have a bit of some "star" lines coming from them—this perhaps could be achieved by making the particles brighter in certain areas?  Sort of a combination of what appears in these two images:      How exactly would I go about doing this? Billboards, or object particles, what sorts of materials, etc.?  (Note: this should work with the glare node on "fog glow")

I'm trying to recreate the blinking star effect seen .  I have created a plane, added a particle emitter and added a sphere as the emitter. In the original sphere particle instance I have used the following node setup.    The Value node has a noise modifier on it to simulate the blinking effect (similar ). When I animate it all of the particles blink simultaneously, rather than each one individually.    How would I make each behave independently?


I received a check with the amount filled in as a number say $2000 but the spelled out portion (which should have been "Two thousand and 00/100") left blank. This was an oversight by the sender (out of state).  Question is can I spell out that number myself? Is that legal and acceptable to the bank? Instead of sending the check back to the original check writer I want to fill in the blank. Is it acceptable?

I've been writing checks this way for the last ~15 years or so:    Namely, the amount field is written using numbers like     1,500 and 00/100    rather than the tedious, painful spelling out of      One Thousand Five Hundred and 00/100   99 times out of 100, this works fine. But occasionally you'll get certain rare human tellers who simply refuse to believe this is a valid check and you have to fight over it. I still figure the time I've saved by not writing out all those ridiculous numbers-as-words is still worth it, overall, but it's definitely irritating.  So: who's right? Is a check with the amount written in numbers valid ... or not?


I'm a physics student that is currently having a lecture on Introduction to Quantum Field Theory. The topics covered are:   Relativistic quantum mechanics Elements of classical field theory Quantization of free scalar fields Interactive Scalar fields: perturbation theory and Feynman diagrams Quantization of Dirac Fields and Spin-1 Fields Quantum electrodynamics Grinding and renormalization   The lecturer did give literature recommendations (Peskin/Schroeder, Aitchison, /Hey and Maggiore), however I believe that for me it would be useful to use literature that gives a different viewpoint on QFT rather than one that focuses on the same approach as the lecture to achieve a more holistic understanding. As far as I am concerned my lecture focuses on introducing the needed mathematical tools and how to use them, which is also the focus of the exercises.   What I now need as an addition to the course would be:   Something that explains the physical motivation and teaches the ideas of QFT, for which I think the book of Griffiths would be nice? (it is recommended in the experimental course and his books are nice to read), but objections can be given. Something with a rigorous approach on why the things we use are the the things we want. Maybe something a bit more in the likes of a mathematical textbook would be nice, as I like clear structure, conciseness (which does not mean short, just concise) and proofs.   Of course a book that would merge both would be great, however I have the feeling that this would be hard to achieve.  I am utterly aware that book recommendations like this have been asked for quite a lot. However they are often quite old, with many books very hard to get nowadays and most of questions focus a lot on the books being introductory and easy to understand or being very complete, which is not quite what I am searching for.

I found Sean Carroll's "A No Nonsense Introduction to General Relativity" (about page .  pdf ), a 24-page overview of the topic, very helpful for beginning study.  It all got me over the hump of learning the meaning of various terms associated with GR, most of which I had heard before without understanding.  It also outlined the most important examples.  Is there a similar document for quantum field theory, which presents the main equations, briefly describes the main ideas, and summarizes the most important applications and results so that the reader can feel the lay of the land before studying in depth?


I want to find some simple surjective function from $\mathbb{N}$ to $\mathbb{Q}$.  Since $\mathbb{Q}$ is countable, it should be possible.  Can someone find such function?

I'm trying to find a surjective function $f:\mathbb{N}\to \mathbb{Q}$;  I know that at least one such function must exist since $\mathbb{Q}$ is countable, but I haven't been able to find one.  Can someone show me one such function?  Best regards,  lorenzo


I currently have an AMD sempron 140 processor in my computer. I plan to upgrade to a used AMD athlon ii x3 450. My question is can I use the stock cooler from the sempron 140 processor to cool the athlon ii x3 450 while still keeping a decent (with decent meaning a temperature where it won't overheat) temperature on it, or will I have to get a new cooler?

I bought an  compatible with a  Socket AM3 processor?  I know strictly speaking, the Lion Square specifies AM2 but I'm a little confused since AM2 and AM3 are suppose to be socket compatible (I'm a little confused here as well but I assume it means an AM3 board will support AM2/AM2+ CPUs).   However, will there be a problem with chip height and spacing? Or do people have experience asking ASUS for a standoff adapter?


Hi i dont know if this question has already been asked before but this is getting really annoying...  Ok so i have a class called Test:  public class Test {     public static Test testObject = new Test(5);//Creates a test object with an initialized value of 5;     int number;     public Test(int number){         this.number = number;     } }   And of course my main class...  public class Main {     public static void main(String args[]){         Test anotherObject = Test.testObject;//this is not a reference right?         System.out.println(Test.testObject.number);//This prints 5         anotherObject.number = 50;// changing anotherObject's number. NOT testObject's Number.         System.out.println(Test.testObject.number);//if that was true this whould of still been 5, but it prints 50!!?? why does testObject's number even change if im not even changing that value?     } }   if there is something im doing wrong please let me know, thank you very much!!

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


I have got two questions and would be extremely grateful for any help (especially with the first question)!  Question 1: I am using the article class and would like the section title (including section number) to appear on the LEFT; additionally, on pages belonging to a subsection, the subsection title (excluding number) should be printed on the RIGHT.  To create the header I used the following code:  \documentclass{article}  \usepackage[english]{babel} \usepackage[utf8]{inputenc} \usepackage{fancyhdr}  \renewcommand{\subsectionmark}[1]{\markright{#1}}  \pagestyle{fancy} \fancyhf{} \rhead{\rightmark} \lhead{\sectionmark} \rfoot{\centering \thepage}  \begin{document}  \section{Introduction}  \section{Chapter 2}   \subsection{A subsection}   \subsection{Another subsection}  \section{Chapter 3}   \subsection{First subsection in Chapter 3}   \subsection{Another subsection in Chapter 3}  \section{Conclusion}  \end{document}   The problem is that with this code, the left-hand header is empty and the right-hand header gives the subsection title (if a subsection exists) and otherwise it gives the section title.  I would be very grateful if someone would show me how to get the desired header, described above!  Question 2: I don't want the header to appear on the first page of a new section. Is there anything one could include in the preamble to achieve this, instead of having to add \thispagestyle{empty}in the code underneath each \sectioncommand?  Many thanks in advance! :)

I'm trying to create a document that has different margins on even and odd pages. This is what I've tried:  \documentclass[a4paper,12pt]{article} \usepackage[slovene]{babel} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usepackage{amsfonts,amsmath,amssymb,amsthm} \usepackage[all,cmtip]{xy} \usepackage{graphicx} \usepackage{resizegather}  \hfuzz=2pt  \oddsidemargin=51pt \evensidemargin=11pt   This would give me precisely the margins I want, but for some reason, \oddsidemargin and \evensidemargin are not independent. When I set one of them, the other is fixed. After reading some answers here, I tried setting changing the first line to  \documentclass[a4paper,12pt,twoside]{article}   but this completely messes with my layout and I get a bunch of "underfull \vbox"'s. (Although the left and right margins then behave as expected.) So, my question is as follows:     How do I make \oddsidemargin and \evensidemargin behave independently without introducing any other (undesired) behaviour?


What I'm wanting to do is create a file watcher that is monitoring for any changes in my services config file. When it detects any changes, the service should restart automatically so the changes can get picked up. However, I'm struggling to get the file watcher to notice that any changes have been made.   Here is my watcher code:   private void WatchConfigurationFile(string path) {     FileSystemWatcher watcher = new FileSystemWatcher();     watcher.Path = path;      watcher.NotifyFilter = NotifyFilters.LastWrite;     watcher.Filter = "Project.MyService.exe.config"; // name of the file I'm wanting to watch      watcher.Changed += new FileSystemEventHandler(OnChanged);     watcher.EnableRaisingEvents = true;  }   Then for the OnChanged method:  private void OnChanged(object source, FileSystemEventArgs e) {     Log.Info("A change in the config has been found. Stopping Service");      ServiceController service = new ServiceController("MyService");     try     {         TimeSpan timeout = TimeSpan.FromMilliseconds(20);          service.Stop();         service.WaitForStatus(ServiceControllerStatus.Stopped, timeout);     }     catch(Exception ex)     {         // ...         Log.Error("Error restarting service: " + ex.Message);     } }   Finally I am calling all of the above with the following call:  public void Run() {     WatchConfigurationFile("..\\InstallFolder\\MyService\\"); }   The Run method is already used with in my service. I have the service running on a timer of which Run gets called at the end of each count down. This method already has other method calls in there, so I know that the Run method is working.  What is it I'm doing wrong with? I've got a funny feeling that my path may be incorrect as the config is in the same location as the service itself. But if someone else is able to shed light on this, it would be appreciated.

If I have the following code:  MyClass pClass = new MyClass(); pClass.MyEvent += MyFunction; pClass = null;   Will pClass be garbage collected? Or will it hang around still firing its events whenever they occur? Will I need to do the following in order to allow garbage collection?  MyClass pClass = new MyClass(); pClass.MyEvent += MyFunction; pClass.MyEvent -= MyFunction; pClass = null;


After push we have  sfdx force:source:push but not able to see helloWorld component on Salesforce  custom tab is empty.

I Create an sfdx scratch org using . I also created a sample hello world lightning web component and pushed it to the scratch org and everything works fine as I was able to preview my hello world lwc in the app builder. I also created an aura component from dev console and was able to pull it to vscode.  Now here comes the issue, Later I created couple of more lwc from the vscode  and used push command after saving them, then It shows me what was pushed to the scratch org and everything was fine, but when I actually went to the app builder page of the scratch org that the code was pushed I don't see the newly pushed Lightning web components. Also every time I try to push some deltas I can see the deltas getting pushed.  How do I verify this issue? At least for aura components I can look into lightning resources to see the components but for lwc Im not sure of a way to verify whether they are pushed or not.  Below are the commands used:  sfdx force:source:push // for push  sfdx force:source:pull // for pull   Note: I was able to see the actual lightning web components in the force-app folder in my local host.  PS: From your scratch org   setup Lightning component opens a list view where you can see aura components and lwc and I can see all the lwc      Even though all the lightning web components are available in the org,   I was not able to see them in the app builder except for the first   one!


Given a permutation, for example:  1234 1243  .  . 4321  Can anybody explain why the differences between numbers are always (no proof, but for all simple permutations) divisible by 9?

I have just proved the divisibility rule for 3 and 9.  Let $n\in\mathbb{N}$. Let $m$ be a number that appears when you shuffle the digits in $n$. Show that $n-m$ is a multiple of 9.  Can anyone offer some help?


I noticed that you can select vertices through other objects. Here is an example to show what I mean:  I have a cube partially inside a sphere. When I do a circle select when the back vertex is hidden behind the sphere...   Both vertices, including the one that was hidden by the object, are selected.   Is there a way to prevent this behavior?  EDIT: I tried the "limit selection to visible" option but it didn't work... I believe this case is different because it is selecting through a different object, not just itself.

I want to select marked face:    however back face gets selected:    Is there an option in blender to only select facing polygons camera ?


For ubuntu or debian, for installed package, I can use dpkg -L package to view where files were installed by the package. For a package is going to be installed but yet installed, how can I foresee these information?

I have installed pulseaudio-module-bluetooth using apt.  $ type pulseaudio-module-bluetooth bash: type: pulseaudio-module-bluetooth: not found $ which pulseaudio-module-bluetooth $ whereis pulseaudio-module-bluetooth pulseaudio-module-bluetooth:   Clearly, I'm looking for the wrong thing.  The package does not simply install a command that is the same name as the package.  Alright, then.  I want to find out what all commands (or executables) this package installed, and their locations.  The answers to "" tell me how to find the files installed by the package if I have a .deb file.  I'm not installing directly from a .deb file, though.  I'm using apt.  Where is the .deb file that that used?  Is there a copy on my system somewhere that I can query with the commands in the answers to that question?  Where?  If there isn't a local copy on my system, can I get one with apt?  How?  Is there some handy apt (or similar) command that wraps this up for me, so that I do not have to run dpkg-deb directly?  What is it?  Can I find the package's file list entirely on-line, without explicitly downloading any .deb files and before installing anything with apt?  How?


I am trying to install Atom editor on to Jetson nano and, as far as I could determine, I selected the commands from link below to install Atom. Being that I am not an expert I am wondering how to correct the  unmet dependencies pasted below.     The issue is the following:  The following packages have unmet dependencies:  atom:i386 : Depends: libgtk2.0-0:i386 but it is not installable              Depends: libudev0:i386 but it is not installable or                       libudev1:i386 but it is not installable              Depends: libgcrypt11:i386 but it is not installable or                       libgcrypt20:i386 but it is not installable              Depends: libnotify4:i386 but it is not installable              Depends: libxtst6:i386 but it is not installable              Depends: libnss3:i386 but it is not installable              Depends: python:i386 but it is not installable              Depends: libdbus-1-3:i386 but it is not installable              Depends: libcap2:i386 but it is not installable              Depends: libxkbfile1:i386 but it is not installable              Depends: libx11-6:i386 but it is not installable              Depends: libasound2:i386 but it is not installable              Depends: libsecret-1-0:i386 but it is not installable              Depends: gir1.2-secret-1:i386 but it is not installable E: Unable to correct problems, you have held broken packages.

After upgrading from 10.04 to 12.04 I am trying to install different packages.  For instance ia32-libs and skype (4.0).  When trying to install these, I am getting the 'Unable to correct problems, you have held broken packages' error message.   Output of commands:  sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.   After running this:  sudo dpkg --configure -a foo@foo:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.


In answering  I found myself linking to a lot of books at . Because it felt like an abuse I did not use my Amazon Associate link as a means to link to each book. However, I am not sure that everyone would have the same opinion that I do. Does the site actively prevent the use of affiliate program links or does it rely upon moderators and users to flag circumspect questions/answers?

I've just read  (now deleted). What is the policy on putting affiliate tags into Amazon links on Stack Overflow? What about other affiliate links?


How to perform update and insert in same query? i need to update the record, if it is not present then it has to perform insertion i tried this   UPDATE bank SET  Address= $2,"PANCard"= $3,"IFSC" = $4  WHERE user_id = $1; INSERT INTO bank (user_id,bank_details,"PAN",bank_acc,"UAN",tax)        SELECT  '$2','$3','$4','$5','$6'        WHERE NOT EXISTS (SELECT * FROM bank WHERE user_id=$1);   but am getting   {   "name": "error",   "length": 123,   "severity": "ERROR",   "code": "42601",   "file": "postgres.c",   "line": "1274",   "routine": "exec_parse_message" }   please help me here

This query works for me when I tried in PG admin query tool:    UPDATE bankdetails SET bank_details = 'mysore' ,"PAN"= 123,bank_acc = 456,                        "UAN"=789,tax = 'myy' WHERE  user_id = 79; INSERT INTO bankdetails (user_id,bank_details,"PAN",bank_acc,"UAN",tax)        SELECT 79,'mysore',123,456,789,'myy'        WHERE NOT EXISTS (SELECT 1 FROM bankdetails WHERE user_id=79);   Later I implemented in my code like this:  db.query('UPDATE bankdetails SET bank_details = $2 ,"PAN"= $3,bank_acc = $4,"UAN"=$5,tax = $6 WHERE user_id = $1; INSERT INTO bankdetails (user_id,bank_details,"PAN",bank_acc,"UAN",tax) SELECT $1,$2,$3,$4,$5,$6 WHERE NOT EXISTS (SELECT 1 FROM bankdetails WHERE user_id = $1);', [companyuser.rows[0]._id, data.bankDetails.bank_details, data.bankDetails.PAN, data.bankDetails.bank_acc, data.bankDetails.UAN, data.bankDetails.tax],function(err,bank) {                  if (err) return callback(new Error('error')); })   it says:     cannot insert multiple commands into a prepared statement   Can some one guide me here?


On my wordpress website i have a calendar page managed by a plugin installed which has some basic links in it Some text.  Somewhere in that plugin there is some Javascript code that once the user clicks on one of those links triggers an AJAX call. Well, I don't want this to happen. And, of course, i don't want to edit the plugin core files.  What i want to do is to simply create a script that removes any action bound to those links so that once the user clicks on one of those links nothing happens. So, i tried with jQuery methods preventDefault(), stopPropagation() and stopImmediatePropagation(), but none of them worked.  jQuery(document).on('click','.mylink', function(event){     event.preventDefault();     event.stopImmediatePropagation();     event.stopPropagation();     //do the stuff i want here });   What am i missing?

I have an input type="image". This acts like the cell notes in Microsoft Excel. If someone enters a number into the text box that this input-image is paired with, I setup an event handler for the input-image. Then when the user clicks the image, they get a little popup to add some notes to the data.  My problem is that when a user enters a zero into the text box, I need to disable the input-image's event handler. I have tried the following, but to no avail.  $('#myimage').click(function { return false; });


I asked a bad question. After many comments from other users and many edits on my part, it is now a good question. However, the comments are littered with corrections to older versions. Should I delete and repost this question, now that it is actually good, or keep the current version up?   This question is distinctly different than   , because I am asking about a question that is still open/has not been closed.

If you    Formulate a question vaguely It gets closed / put on hold for this You take the comments to heart and reformulate it It no longer gets attention but you have not enough reputation to trigger a reopen.   Then is there anything you can do? Is closing the question and stating it as a new question a legitimate solution? I have the feeling it is not, but did not find any info here on meta.


We've added a reference to a web project, which we would now like to check in in TFS. For a normal project, you would just check in the project file (.csproj). However, a web project does not have a project file. Does anyone know in which file the references of a web project are stored, so we can check in only that file?

In Visual Studio website projects (in Visual Studio 2005 or later, not web application projects where there is still a .csproj file) how is the reference information stored, and is it possible to source control it without storing compiled binaries in source control?  If you right-click on a website project and select Property Pages, the first screen (References) lists all the project references.  System.* references are listed as type GAC, and other DLL files can be listed as BIN or Project.  The problem occurs when you include something as a project reference, and then commit it to source control (for us, Subversion, ignoring .dll and .pdb files.)  Another developer gets updated code from the repository and has to manually set up all of these project references, but I can't even determine where this information is stored, unless it's in that .suo, which is NOT source-control friendly.


I was wondering if I'm safe from SQL injection if I have this in a script:  < script>      //some stuff      var item = <?php echo json_oncode($PHPVAR) ?>      item.replace(/"/,'&quot').replace(/'/,'&#39');      //do more script stuff with item  < /script>   currently using Laravel (PHP), with PDO Are there anything else that I should be aware of/look out for? (I didn't whitelist/blacklist before submitting to database b/c PDO does that for me from what I understand)  Also I'm asking b/c item is taken from a user input and it dynamically creates HTML using the value of item

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


The files are named file00 through file99 (hundred files). They are all in the same directory. How do I grab all the hundred files and delete the first 10 lines from each file? I am using CentOS 7.

I have multiple files that contain ascii text information in the first 5-10 lines, followed by well-tabulated matrix information.  In a shell script, I want to remove these first few lines of text so that I can use the pure matrix information in another program.  How can I use bash shell commands to do this?    If it's any help, I'm using RedHat and an Ubuntu linux systems.


For example, i = 'cat', how can I get this output: 'at', 'ct', 'ca'? I wrote a code like this, but totally wrong. Can anyone help? for x in i:     print(i.replace('x', ''))

I have a list with 15 numbers in, and I need to write some code that produces all 32,768 combinations of those numbers.   I've found  (by Googling) that apparently does what I'm looking for, but I found the code fairly opaque and am wary of using it. Plus I have a feeling there must be a more elegant solution.  The only thing that occurs to me would be to just loop through the decimal integers 1–32768 and convert those to binary, and use the binary representation as a filter to pick out the appropriate numbers.   Does anyone know of a better way? Using map(), maybe?


I have Dynamic Web Application deployed on Glassfish server. Inside my application I have a java function that is invoked every time certain JMS Message is received. Depending on JMS Message, I want to update the state of web application that is loaded inside web browser - I need to call certain Javascript function as soon as the JMS Message is received.   How can i accomplish that? Is there any java and/or Javscript library that can do this?  Any help will be greatly appreciated, thank you.  P.S. After Some research i have found a very useful library that does exactly what i wanted:

Of course I am aware of Ajax, but the problem with Ajax is that the browser should poll the server frequently to find whether there is new data. This increases server load.  Is there any better method (even using Ajax) other than polling the server frequently?


So, I have a small application and I made an "extra" JTextField for the user to input Yes or No if he wants extra data.  I use this method:   process(file.getText(), Integer.parseInt(aText.getText()),                     Integer.parseInt(bText.getText()), cText.getText(),                     dText.getText()); //dText is the one I have problems with   In   public void process(String name, int a, int b, String obs, String extra) { ... }   I wrote this  if(extra== "yes"){             writer.write("Success!");         }   but it is not working.  If I was to write just  writer.write(extra);   it would have worked, by that it means that it can read the text I input but still I can't use the If-statement. Am I doing something wrong or that is not possible at all?  here is my full code :   Sorry for my bad english.

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


I have 3 independent querys that I would like to sum the values obtained in each query. These querys obtain a count value for each day of a month:  query one  day|val|  1  | 2  2  | 6  3  | 5*  4  | 2  5  | 7   query 2  day|val| 2  | 1 3  | 5* 10 | 5 11 | 2 12 | 7   I am using the instruction:  select day, SUM(val)  from query1 UNION query2 group by day   I found out that when a value is repeated instead of sum it would use one of the repeated values, for axample the days number 3 both have value 5. the instruction would give onlye value 5 instead of 10.  This is supposed to give me a report of total of values per day in a month but the report is wrong because of this problem caused by UNION How can i fix it?

What is the difference between UNION and UNION ALL?


Hey guys so the other day my laptop updated to 8.1. After install it required a restart, i clicked yes and now its been stuck in an infinite preparing start up repair.  So i installed ubuntu to USB booted from that in a hopes to access my windows partition through that and copy everything off. However every time I try access the drive it gives me "the NTFS partition is in an unsafe state please resume and shutdown windows fully"   I've tried running several sudo commands but none seem to be working!  any help appreciated.   the command being   sudo mkdir /mnt/new  sudo mount -t ntfs -3g -o remove_hiberfile /dev/sda1 /mnt/new   the error being  the NTFS partition is in an unsafe state. please resume and shutdown windows fully (no hibernation or fast restarting) or mount the volume read-only with the 'ro' mount option.

Whenever I boot Ubuntu, I get a message that it cannot mount my windows partition, and I can choose to either wait, skip or manually mount.  When I try to enter my Windows partition through Nautilus I get a message saying that this partition is hibernated and that I need to enter the file system and properly close it, something I have done with no problem so I don't know why this happens.    Here's my partition table, if any more data is needed please let me know.     Device Boot      Start         End      Blocks   Id  System /dev/sda1            2048    20000767     9999360   83  Linux /dev/sda2        20002814   478001151   228999169    5  Extended /dev/sda3   *   478001152   622532607    72265728    7  HPFS/NTFS/exFAT /dev/sda4       622532608   625141759     1304576   82  Linux swap / Solaris /dev/sda5        20002816   478001151   228999168   83  Linux


I have used collection initializer for a Dictionary and received a TypeInitializationException:  public static Dictionary<Environment.SpecialFolder, string> specialFolders = new Dictionary<Environment.SpecialFolder, string> {     // ...     {Environment.SpecialFolder.MyDocuments, "abc"},     // ...     {Environment.SpecialFolder.Personal   , "def"},     // ... };   As there is no useful info like InnerException, call stack or whatever else it is confusing. So I investigated the problem a bit and realized that there are two keys having the same value.   Regarding the IL, this collection initializer syntax is converted to Dictionary.Add(...) calls and as such calling Add two times with the same key raises System.ArgumentException (which is the inner exception I would expect in the TypeInitializationException). So I effectivelly answered my original question, but another one has emerged:  Why the class has to implement IEnumerable (and thus provide IEnumerator) - which is intended to read the collection, not to write it - when finally the collection initializer is converted to Add call (which is not guaranteed to be present in the class via the IEnumerable)? Am I missing something important?

I was looking at C# collection initializers and found the implementation to be very pragmatic but also very unlike anything else in C#  I am able to create code like this:  using System; using System.Collections;  class Program {     static void Main()     {         Test test = new Test { 1, 2, 3 };     } }  class Test : IEnumerable {     public IEnumerator GetEnumerator()     {         throw new NotImplementedException();     }      public void Add(int i) { } }   Since I have satisfied the minimum requirements for the compiler (implemented IEnumerable and a public void Add) this works but obviously has no value.  I was wondering what prevented the C# team from creating a more strict set of requirements?  In other words why, in order for this syntax to compile, does the compiler not require that the type implement ICollection?  That seems more in the spirit of other C# features.


Been working on this fire simulation.  I'm new to the simulation but have done a ton of fiddling around with settings and looked at some questions.  Why is the domain not rendering correctly?  It's rendering as a solid cube (bottom picture) instead of the simulation.  Also, I am in Cycles Render.  Thanks in advance,  Tyler

I am trying to render smoke in cycles, but the relevant blender  is designed for Bender Internal. I have everything set up except for the material.  I imagine you would set up the material nodes something like this:    But the problem is that there is no Voxel Data texture node, ans I am not sure what kind of shader should be used.  Is smoke in Cycles simply not supported yet? Or do I need to go about this a different way?   Reference:


I've read all the postings here including the one that said it was already answered and elsewhere for this apparently common problem but so far I have not been able to resolve it. The other answers did not help. Typically I keep my systems up to date but this PC has been in storage for a year and a half during a remodel and now that it is back online, it needs to be updated/upgraded from the EOL 19.10 to 20.10 but it fails, then immediately wants to update again. $ sudo apt update Ign:1 http://us.archive.ubuntu.com/ubuntu eoan InRelease Err:2 http://us.archive.ubuntu.com/ubuntu eoan Release                           404  Not Found [IP: 91.189.91.38 80] Hit:3 http://archive.ubuntu.com/ubuntu xenial-updates InRelease                Hit:4 http://archive.canonical.com/ubuntu xenial InRelease Hit:5 http://archive.ubuntu.com/ubuntu xenial-backports InRelease Hit:6 http://archive.ubuntu.com/ubuntu xenial-security InRelease Reading package lists... Done E: The repository 'http://us.archive.ubuntu.com/ubuntu eoan Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.

Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:  $ sudo apt-get install vlc Reading package lists... Done                Building dependency tree        Reading state information... Done     E: Couldn't find package vlc


i have a table name users and i want to download to csv file by a query, but i dont want to select a password column in table users.  i am new to sql that to fresher, please any one help me.  below is my query  function get_all_partnerships_to_download() {          $this->db->select('*');         $this->db->from("$this->_users_table");         $this->db->join("$this->_user_profile_table",  "$this->_user_profile_table.user_id = $this->_users_table.id");         $this->db->where("$this->_user_profile_table.participate_as_id", 3);         $this->db->group_by("$this->_users_table.id");         $this->db->distinct();          return $this->db->get($this->_table);      }

I'm trying to use a select statement to get all of the columns from a certain MySQL table except one. Is there a simple way to do this?  EDIT: There are 53 columns in this table (NOT MY DESIGN)


How do I give my math.random a parameter in such a way that I will always receive at least, but not more than 3 digits? I'm currently in my first programming class at a community college, and this is an assignment for a small lottery program in Java. Any help or more of an in-depth explanation would be highly appreciated. Thank you!  //randomly generate 3 digit lottery number     int lottery = (int)(Math.random() * 1000);      System.out.println(lottery);      int lotteryDigit1 = lottery / 100;     int lotteryDigit2 = lottery / 10 % 10;     int lotteryDigit3 = lottery % 10;      System.out.println(lotteryDigit1 + " digit 1 ");     System.out.println(lotteryDigit2 + " digit 2 ");     System.out.println(lotteryDigit3 + " digit 3 ");     To help clarify the basis on which I am writing this program, here is a similar program that generates "2" random numbers for lottery. My job is to modify it to create 3 random numbers.  public static void main(String[] args)  {      //generate lottery number     int lottery = (int)(Math.random() * 100);      //prompt the user to enter a guess     Scanner input = new Scanner (System.in);     System.out.println("Enter your lottery pick (two digits): ");     int guess = input.nextInt();      //get digits from lottery     int lotteryDigit1 = lottery / 10;     int lotteryDigit2 = lottery % 10;      //get digits from guess     int guessDigit1 = guess / 10;     int guessDigit2 = guess % 10;      System.out.println("The lottery number is " + lottery);      //check the guess     if (guess == lottery)         System.out.println("Exact match: you win $10,000");     else if (guessDigit2 == lotteryDigit1 && guessDigit2 == lotteryDigit2)             System.out.println("Match all digits: you win $3,000");     else if (guessDigit1 == lotteryDigit1             || guessDigit1 == lotteryDigit2             || guessDigit2 == lotteryDigit1             ||guessDigit2 == lotteryDigit2)         System.out.println("Match one digit: you win $1,000");     else         System.out.println("Sorry, no match");       }   }

How do I generate a random int value in a specific range? I have tried the following, but those do not work: Attempt 1: randomNum = minimum + (int)(Math.random() * maximum);  Bug: randomNum can be bigger than maximum. Attempt 2: Random rn = new Random(); int n = maximum - minimum + 1; int i = rn.nextInt() % n; randomNum =  minimum + i;  Bug: randomNum can be smaller than minimum.


I'm working on the following problem:  Let $f:[a,b]\rightarrow\Bbb{R}$ be such that $f(x)=0$ except at finitely many points. Show that $\int_a^b{f(x)}dx=0$.  Am I pointed in the wrong direction for wanting to use contradiction? If I assume $$\int_a^b{f(x)}dx\neq0$$ then can I assume $f$ must contain a variable x such that $f$ is not a constant? Is it that simple? I'm missing a lot of connections.

Proving that, if a function $f:[a,b] \rightarrow \mathbb{R}$ be zero except at finitely many points, it is Riemann-integratable with integral $0$ :  Let the function attain non-zero values at $x_i $, where $i={1, 2, 3,...n}$, where $x_i<x_{i+1}$, with respective values being $a_i$.  Let us now split the domain into finite number almost disjoint intervals, $I_1, I_2, ..., I_{\omega}$ , thus forming a finite partition of $[a,b]$ . Let us now assume a finite subsequence of intervals, $I_{n_1}, I_{n_2},..., I_{n_k}$, containing the respective non zero values. It is to be noted, with proper "refinement" of partitions, we can make $max\{k\}=n$  [as $n$ is finite].  Further, assume the length of the respective subintervals, containing the numbers be $ \delta_i$, where $i$ runs from $1$ to $k$.   When $k<n$, we have $sup(f)_{I_{n_i}}=max\{a_{t_i}\}=\alpha_{t_i}$ [ where $a_{t_i} \in I_{n_i}$ ] and $inf(f)_{I_{n_i}}=0$. For this type of partition modes, we have $U(f;P)= \sum_{i=1}^{k} \delta_i \alpha_{t_i}  $ and $L(f;P)=0$.  As the subintervals containing the points containing $x_i$ becomes fine enough, we can have $x_i \notin I_{n_a} \cap I_{n_b}$ for any $i, a$ and $b$. Now, we have $U(f;P')= \sum_{i=1}^{n} \delta_i x_i \leq U(f;P)  $ with $L(f;P')=0$ as usual.   Now, as the norm of the partition $P'$ approaches $0$, i.e. $ ||P'| | \rightarrow 0$, $\delta_i \rightarrow 0 $. Hence $ \mathbf{inf} \ U(f; P')=0$. So,   $ \mathbf{inf} \ U(f; P')=0= \mathbf{sup} \ L(f; P')$.  QED  Is the above proof adequate and valid?


I'd like to make a boolean table with some inputs x, y, z and some outputs a, b, and label the first three columns In and the last two Out. The  shows me how to merge all columns across a table, is there a way I can merge the first n in a row, and then the remainder in the same row?

I have this table, but wanted to format the first row. I like to match the two columns of first row, and last two columns of the same first row. Any suggestion on how to do that?  \begin{table}[!h]  \caption{Comparison of percentages.} \begin{tabular}{lclclclclc} \hline \hline  Mode &  Var  &  Cum\\ \hline {}       & EF   & CHF    & EF2   & CHF2\\ 1   &  17.5 & 19.1   & 17.5  & 19.1\\ 2   &  11.8 & 12.7   & 29.3  &  31.9\\ 3   &  6.6  &  5.6         & 35.9    &  37.4\\ \hline \end{tabular} \end{table}


I have seen similar questions, but in all those answer, you can only get the variable by position. How can one pass a named variable to a bash script such that it is accessible by its name in the bash script? I have tried to use os.system('./script.sh --key=val')  But $key didn't have any assigned value in script.sh.

Say, I have a script that gets called with this line: ./myscript -vfd ./foo/bar/someFile -o /fizz/someOtherFile  or this one: ./myscript -v -f -d -o /fizz/someOtherFile ./foo/bar/someFile   What's the accepted way of parsing this such that in each case (or some combination of the two) $v, $f, and  $d will all be set to true and $outFile will be equal to /fizz/someOtherFile?


In (TOS) "The Tholian Web" the USS Defiant (NCC-1764) got pulled into another dimension that we later find out (in Enterprise: “In a Mirror, Darkly”) is the Mirror Universe about 100 years in the past of TOS and is subsequently captured by the Terran Empire.   In (Discovery) "Despite Yourself" the USS Discovery (NCC-1031) is in the Mirror Universe and encounters the ISS Shenzhou (NCC-1227) with what appears to be just about exactly the same tech as the Prime Universe USS Shenzhou (NCC-1227) had.   So the Question is...  With about 100 years of time with a future ship from an alternate timeline how is it that the Empire did not develop significantly advanced technology and design far more advanced ships by reverse engineering the USS Defiant (NCC-1764) and going through its memory banks?  Examples of Alien Tech in Star Trek being reverse engineered in a short period are. (these may not be accurately remembered examples but the question still stands valid)  It only took roughly 30 years to develop the Mobile Emitter for the Doctor in (Voy) "Future's End, Part II" in 1996, something they hadn't even developed in own Voyagers Timeline. Not to mention the computer chip revolution that happened due to this.  In (Voy) "Endgame" Admiral Janeway Travels into the past and within days helps the Voyager develop and implement Technology that wasn't designed for their systems and significantly enhances Voyagers Defensive capabilities.   In (DS9) "Shattered Mirror" the Tarren Resistance Developed and built a Defiant using "acquired" specifications from DS9 in 2371, only needing Sisko's help at the end to fix the same structural issues that the Prime Sisko had when developing the ship.

In Star Trek TOS, we see the Defiant disappear to unknown parts  ('The Tholian Web'), and Star Trek: Enterprise revealed that the Defiant went back in time to the mirror universe ('In a Mirror Darkly', parts 1 & 2).   Because of this, one might wonder why (in-universe) the mirror universe didn't obtain (and maintain) technological superiority over the main timeline. (Granted, the out of universe answer is that TOS depicted the two universes as having essentially the same level of tech)  So does any work (whether STO, or a pocket books work) address why the mirror universe didn't simply leap frog the main universe's technology?   (Or to put it another way, why did the mirror universe's technology appear to stagnate for a century after obtaining access to the Defiant's advanced technology?)


I have a Roleplay Forum, and I would like to add a map of my Roleplay World to the website.  I would like my map to be clickable, and have each location take you to a place on the forum. I don't know coding outside of basic basic  prosilver.  I want the map to be an image, a large one, where you can scroll around the element like a map and then click on a city, location or land and it takes you there on the forum.

I want to start working on a web map at work to map some of our statistics by city.    I have an idea, but I'm not exactly sure where to start.   Are there any definitive resources that provide step by step guidance on how to do this?


Up until recently I was under the impression that Unix-y programs were unaware of where their output went, be it to standard out, redirected to a file, or into a pipe. However, an unrelated U&L question on this site brought to my attention the following example:  % echo "hello world" > file  % grep --color=auto lo file hello world  % grep --color=auto lo file | cat hello world   Obviously you can't see it here, but the first command shows 'lo' highlighted, as expected. However, the second call, which goes through a pipe, shows no colour. This suggests that grep was aware of its output being directed to a pipe and avoided outputting colour. How is this done?

How does commands like ls know what its stdout is?  It seems ls is operating different depending on what the target stdout is. For example if I do:  ls /home/matt/tmp    the result is:  a.txt b.txt c.txt   However if I do  ls /home/matt/tmp | cat   the result is (i.e. new line per result):  a.txt b.txt c.txt   The process is passed a file descriptor 1 for stdout right? How does it determine how to format the result? Does the file descriptor reveal information?


$\tan^{-1}(x)$ looks very similar to $\tanh(x)$ if $x$ is small enough.  Look.    But they diverge from each other as $x$ grows.    And for very big $x$'s, They almost represent the constant functions $1$ and $\frac \pi 2$ (for $\tanh(x)$ and $\tan^{-1}(x)$, respectively).    Is it possible to write $\tan^{-1}(x)$ as a power expansion of $\tanh(x)$?  I mean can we say this?  $$\tan^{-1}(x)=\sum^{\infty}_{i=0} \alpha_i \tanh^i(x)$$   The power series is the thing I want. Not the resemblance between them.

The functions $\tanh x$ and $\arctan x$ have a similar graph. Is there a formula to transform $\tanh x$ to $\arctan x$?


I read a short story in an anthology of science fiction in the mid-1990s about a scientist who is genetically engineering rat-like creatures for increased intelligence. Eventually these animals develop sentience and flight, and are told by the scientist that they come from a star in the sky (Venus?).  The story ends with the animals stealing a space ship and flying off to return to their supposed 'homeland'. Any ideas of what this could have been?

A scientist encloses a community of mice inside a machine that makes time go much faster inside the machine. Thus he can breed successive generations of mice incredibly quickly. He breeds the population to have wings and to be intelligent.  After innumerable generations he produces the required creatures. He is able to communicate with them but discovers they are curious about their heritage. He invents a mythology that their race comes from the planet Venus.  They somehow obtain a space-craft and take off in search of what they believe to be their 'home' planet.    I believe it might have been part of an anthology and was probably written before 1970 although that's not certain. The language was English but I can't remember if American or British. There were no characters apart from the scientist and the mice as far as I can remember.


This could possibly include meteorological data/precipitation data aggregated on the district level and power line/ electric transmission infrastructure locations

Does anybody know where I can find a shapefile of the major components of the Indian electricity grid?   Ideally, I'd get transmission/other high-voltage lines, substations, generating units, and transformers. I know there are power maps out there (like ), but I want to match these transmission lines up with geographical data, so more precise locations would be helpful.


for some cloud syncing purposes I want to give TMS (Titanium Media Sync) superuser privilege over my rooted device even if it doesn't asks for it.  I use SuperSU.

Is there any way that I intentionally grant root permission to some app? Not automatically via SuperSU when a specific app asks for root permission, but in a way to pick an app via some tool and grant it root permissions.   For example, I add my favourite text app to the approved list and then I can open root files via that app.


Here's my code:  <apex:repeat var="oi" value="{!relatedTo.OrderItems}">     <apex:outputText value="{0,number,#,##0}">     <apex:param value="{!oi.Quantity}" /> </apex:outputText>   Let's say we have a product family of "in-person-event" and another of "online-subscription". Is there anyway to exclude those product line items from being generated?  Thanks!

I have an output panel inside my apex:repeat tag.  My requirement is to conditionally display it.  So for one element in apex:repeat this panel might be rendered ..for some not. Rendering condition is,i need to check whether  line item occurs in  another controller set variable.  I find it difficult because of following reasons;  1)I understand you cannot check whether a set variable contains this element on visualforce page .or is this possible  2) i can see you cannot pass arguments in your rendered attribute.else i could have specify a boolean value for rendered attribute and set the value based on lineitem passed from front end  3)as the set variable is totally unrelated to line item.i cannot simply specify as below  <apex:repeat value="{!Proposals}" var="item">         <apex:outputPanel rendered="{!item.LineCount > 0}">             <li>              </apex:outputPanel>     </apex:repeat>   Any clue experts Also it is one icon on the element i don't want to display.(not the whole element as such)(but that doesnt make much difference i guess)


If I have a noun of cardinality 1, I am taught that I use the singular form.   E.g. I have 1 Apple    If the value is still 1, but represented as 1.0, do I still use the singular form?  E.g. I have 1.0 Apple  It seems laymen would say I have 1.0 Apples; is this just a trick of the brain but not valid English, or is plural correct even though the value is still 1?

Possible Duplicate:          I'm working on a website that displays distance to various locations to the nearest 1/10 mile. One of the developers (a non-native speaker) asked me an interesting question: If the distance is 1.0 mile(s), is that singular or plural? Clearly, anything other that 1.0 is plural, but is it:     1.0 miles away   or     1.0 mile away   The first option sounds more correct to my ear, but the voice of my elementary school language arts tells me that the latter option is correct.  Edit: Added the word 'away' to the example. It doesn't change the question, but might provide clarity for the answer. Also, regarding numbers between 0 and 1, after more thought, I'm not sure that the answer is as clear as I originally thought. See .


How many solution does $x+y+z=11$ have where $x, y, z$ are non-negative integers. In light of the restrictions, its clear that $x,y,z \in \{0,1,2,..11\}$. So, at face value I would assign a value for $x$ and determine the different combinations that $y$ and $z$ can hold. For example,  For $x=0$, we have $y+z=11$. With writing them out I found that there are $12$ different assigned combinations for $y$ and $z$ that satisfy the equation. For $x=1$, I got $11$. Consequently, the pattern becomes clear whereby each one takes a value less by one. Hence, the number of solutions is $1+2+3+4+5+6+7..+12=78$. I was wondering if there is an easier method perhaps with combinations equation $C(a,b)$..?

Help me understand problems of this type a bit more intuitively.   The solution $C(3+11−1,11)$ seems simple enough, but I got stuck thinking about how many integers you are choosing from within $x_1$, $x_2$, and $x_3$ and I was trying to get an $n$ - as in $C(n+r-1,r)$ - this way. Also, I though the $r$ was 3 since you have $x_1$, $x_2$, $x_3$ choices. Basically, I went wrong at every step. Help!


I am read Abstrac Álgebra, Gallian and I am thinking how to prove this Theorem The first implications is ready but the second implication I dont know...  Can you give me a Idea.  Let F be a field, I a nonzero ideal in F[x], and g(x) an element of F[x]. Then, I=⟨g(x)⟩ if and only if g(x) is a nonzero polynomial of minimum degree in I.

Let's start with a definition:     Definition: Let $F$ be a field, $I$ a nonzero ideal in $F[x]$, and $g(x)$ an element of $F[x]$. Then, $I= \langle g(x)\rangle$ if and only if $g(x)$ is a nonzero polynomial of minimum degree in $I$.   Now it gets completely foggy what is meant with "minimum degree".I constantly come across the "minimal polynomial". This seems to be linked, but it seems strange that there is a division here.   Could someone give a pointer to what the second line actually means. Maybe some example or diagram (if possible) would help a lot here.


This is my first post here so please let me know if I'm doing this wrong...  I'm looking to take the last day of each month for the last 60 months, from a reference date.  For example, if the reference date is today (Aug 21 2014), then the last end of month is July 31st, 2014, and the one before that is June 30th, 2014...  Does anyone know how to do this in python?  Thanks!

Is there a way using Python's standard library to easily determine (i.e. one function call) the last day of a given month?  If the standard library doesn't support that, does the dateutil package support this?