Using "is" versus "are" in a relative clause

I have run into a small question that I would like to check. When referring to one person out of a group, would one use "is" or "are"? For example:   I know you are one of the members that is running things.  I know you are one of the members that are running things.    For singular "one" it should be "is", but for plural "members" it should be "are". I'm hitting a mental block here and I'm uncertain, so any clarification would be greatly appreciated.


Catch 404 after changing permalink structure from /%postname%/ to /%category%/%postname%/

I made a site some time ago and after some days some posts were indexed by search engines. Today I changed the permalink structure from /%postname%/ to  /%category%/%postname%/.  After that, when people come to my site from search engines a 404 page not found error appears. I want to change all old URLs to the new category base URL without any 404 error.  How can I do it? By the way, I use Yoast plugin.


C#,  a String's Split() method, how can I put the resulting string[] into an ArrayList or Stack?


How to fix a bug due to bibtex 3.3 naming changes?

I want to use a special and uncommon option package for bibtex: BIBLATEX-SWISS-LEGAL-BASE . I resume my document as following:  \documentclass{report}     \usepackage{filecontents}     \usepackage[french]{babel}     \usepackage[utf8]{inputenc}     \usepackage[style=biblatex-swiss-legal-bibliography, backend=biber]{biblatex}   %The code work with default config \begin{filecontents}{Sandbox.bib}     @misc{LoursKnuth,         author = {Lours, Donald},         year = {1977},         title = {L'origine du monde},     } \end{filecontents} \addbibresource{Sandbox.bib}  \begin{document} \printbibliography Je doute de mes capacités à résoudre ce problème \cite{LoursKnuth}. \end{document}   Since the transformation of bibtex 3.3 the package is no more usable and display this kind of error:  ! Illegal parameter number in definition of \blx@defformat@d. <to be read again> 5 l.355 \usebibmacro{name:last}{\ifblank{#5}{}{\textsc{#5}\addspace}\textsc... You meant to type ## instead of #, right? Or maybe a } was forgotten somewhere earlier, and things are all screwed up? I'm going to assume that you meant ##.   I imagine that the package has to be maintained but meanwhile is it possible to use a simple "fix tip" for all this. As far as I didn't write myself the package, make correction in the macros is not possible for me (like in ).  I remplaced the biblatex-swiss-legal-base provided by @moewe as suggested in . it didn't fix completly the problem, the following error appear:  l.215 \DeclareSortingTemplate {ntyintro}{% Code en test non mentionné dans l... The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined.   it happens in the corrected .bbs . and then a worst one: ! LaTeX Error: Missing \begin{document}.


Proving that a Jordan basis is not uniquely determined.

It seems that a Jordan basis, for, say, an operator $φ:V→V$ with $V$ a vector space can have several Jordan bases. However I don't see how this is true and I didn't achieve to prove it. Indeed I tried assuming the uniquness of a Jordan basis of $\varphi$ to achieve a contradiction but I did not find any.. I also looked up on mathstack but the only thing I found was this:  And it doesn't realy help because I'm more looking for the general case, which is unclear to me. Could anyone explain why this is true and help me proving it ?


Finding documentation for changes to syntax/parameters of ArcPy tools/functions in ArcGIS Pro?

In a Q&A on this site I recall @KHibma pointing out where in the ArcGIS Pro Help any changes to the syntax (like extra parameters) of a particular tool/function since ArcGIS Pro 1.0.0 could be found.  I have searched hard to try and relocate that Q&A without success so, if my recollection is correct, can anyone point me at where to find that documentation or that Q&A (which this will be a duplicate of)?


What does the expression “rabbit-out-of-a-hat” mean?

I read this phrase on a guide for texts about mathematical logic, it says that this proof is “rabbit-out-of-a-hat”.   What does this mean?  Is it a slang expression? The exact sentence is:      A little unfortunately, the proof of that is rather too   rabbit-out-of-a-hat for my liking.


How do I prevent an application from opening a web browser in Windows 10?

Is there a way to disable this security vulnerability?  Absolutely any application seems capable of opening Edge to any web page it likes without prompting the user.


I have just installed Ubuntu 16.4 to one of the computer in my working place, and done all the required settings configurations which is required to run the particular take in my working place. I am working as an instructor in the department of computer science engineering. I have nearly 50 computers in a lab. So my question: is it possible to take the backup of the entire OS with the setting I had made and put it in to the rest of the computers instead of installing one by one, so that it makes me too easy to setup a lab with minimum time. Can you help me it this regard.


Derivative (or differential) of symmetric square root of a matrix

Let A be a square, symmetric, positive-definite matrix.  Let S be its symmetric square root found by a singular value decomposition.  Let vech() be the half-vectorization operator.  Is there a convenient expression for the derivative (or differential) of vech(S) with respect to vech(A)?  I know the expression for an inverse, which is sort of like a matrix version of the power rule.  Would this approach work for a symmetric square root as well (i.e., (1/2)S^(-1/2))?


Reorder / Fill the missing numbers in a sequence using MySQL

I have a table "number" having a column "n" which is of type int. I inserted some values like,  n -- 1 3 5   8   10  Now I want to the column n as 1,2,3,4,5. That is 3 should be changed as 2, 5 as 3, 8 as 4 and 10 as 5. The values of column n should be reordered with the missing values. How can I do it?


Avoiding getting suspended for voting irregularities?

Many times when I read threads, I keep on upvoting for the reason being that if someone has put an effort to write a big answer, s/he/it should get some rewards for it.  I recently saw someone getting suspended for voting irregularities.   So, I was wondering if I use the total amount of votes allowed per day, daily, will I be suspended?


How many nucleic acids is there in "one molecule of DNA"?

I am confused...  People usually say that "DNA" is made of two strands deoxyribonucleic acid bound together. Nonetheless, the acronym "DNA" means "deoxyribonucleic acid".   So by logic, a molecule of "DNA" should be only made of one strand of deoxyribonucleic acid, and not two! Right?  This is really confusing...


We have a spring attached to a wall and at the other part an object on a frictionless surface. I tried to calculate the spring oscilation period. I used the conservation of energy and kinematics equations for the average acceleration. $$\frac{1}{2}kA^2 = \frac{1}{2}mv^2 \Rightarrow v^2=k\frac{A^2}{m}$$ $$v^2=2aA+v_0^2=2aA \Rightarrow \frac{kA^2}{m}=2aA \Rightarrow a= \frac{kA}{2m}$$ $$v=at \Rightarrow \sqrt{\frac{kA^2}{m}}=\frac{kA}{2m} t \Rightarrow t= 2 \sqrt{\frac{m}{k}}.$$   This only the motion from the amplitude to the $x=0$ position. The forward 3 parts are the same because the kinetic energy is constantly transformed into elastic potential.  $$T=4t=8 \sqrt{\frac{m}{k}}$$ I used the kinematics equations for some average acceleration of out varrying acceleration. The formula said $T=2 \pi \sqrt{\frac{m}{k}}$. $\pi$ doesn't equal 4.  Can anybody explain how to derive the formula ?


Some times my laptop gets stuck due to excessive usage of RAM when I open bulky applications. So if it does not respond I shut down the laptop using the power button. Does this damage Ubuntu in any way? Can it give rise to security problems or vulnerabilities?


As generally acknowledged TeX offers superb formatting capabilities for math in an automated fashion. Nevertheless there are some areas with clear deficiencies  that one either has to accept or manually improve on a case by case basis.  One of the biggies in that respect is TeX's handling of sub-formulas (i.e., material inside a brace group, e.g., and index, but also any group on top-level). TeX sets such sub-formulas always in natural width even if the whole formula is subject to severe stretching or shrinking otherwise. As an example, consider the following (not very sensible) example:  \documentclass{article}  \newlength\x  \begin{document}  \newcommand\formula{$ a+\mathbf{b+c}+d+e+f = \sum_{i=1}^{n-x-y-z} x_{i+j}$}  \settowidth\x{\formula}  \hbox to \x{\formula}    % natural width  \addtolength\x{-20pt}  \hbox to \x{\formula}   % now shrink it a lot  \addtolength\x{100pt}  \hbox to \x{\formula}   % now stretch a lot in the opposite direction  \end{document}   The formula here has a number of obvious sub-formulas in the subscripts and superscript, but for illustration I also added a sub-formula via \mathbf. Of course the usage of \mathbf in this way is wrong!!! (it should not be applied to several symbols), but I'm sure you would find this in documents. In any case just {b+c} would have had the same effect here. Now what do you think happens if we run this?  This:    As one can see the naturally "boxed" sub-formulas are very wrong the moment the rest of the formula is subject to stretching or shrinking.  Until recently no TeX engine successor addressed this issue. With LuaTeX opening up a lot of the internals of TeX I had some hope that this would be different. However, upon studying the manual my conclusion is that this area (sor far it least) has not been addressed (or considered).  As far as I can see the only way something could be done in LuaTeX about this issue would be to  use the mlist_to_hlist callback. However, this would really mean replacing the full math typesetting algorithm, which of course could be a way to solve the problem but ... but what is needed is not that (as 99% of this algorithm is next to perfect) but to add support to not simply box sub-formulas at their natural width.  So long text ... here is the short question:   Is this analysis correct, or did I overlook something? And in case anybody knows: are there plans to look into the sub-formula issue and provide support for it eventually? (it is not listed on the "to-dos" for math)    In case somebody wonders that I talk about "this sub-formula issue" as if it is something like a known thing ... it is, it was already raised way back in  which at the time a some thorough (if not say heated) discussions.


One who is repulsed by / dislikes something

What would you call someone who dislikes, say, the taste of chocolate?  They have a non-preference for it.  '-phobe' doesn't seem to fit as it implies they want it to suffer or be destroyed, or they are frightened of it.  'antiphile' isn't a word and neither is 'contraphile'.  The closest similar question I've found was ''.  EDIT: As mentioned by @ermanen there is a very similar question:   I was not necessarily after a suffix and was looking for an 'identity' term.  EG: A person who dislikes the taste of chocolate and is quite secure in and not embarrassed by it.  This person does not bear ill will to those that do like the taste of chocolate.


how to validate url with end of .xml regular expression in javascript

I have created a url field and submit button.and i want to validate this url like that it will show .xml regular expression at the end of url instead of .com and anything else. I have tried this code but didn't get reliable solution.It's redirecting me on another page when i writes invalid url.  Please help me through this . Any help will be appreciated.  Thanks in advance.  function validateURL(){ var re = /^(http[s]?:\/\/){0,1}(www\.){0,1}[a-zA-Z0-9\.\-]+\.[a-zA-Z]{2,5}[\.]{0,1}/.xml; if (!re.test(url)) {  alert("url error"); document.getElementById("error_msg").innerHTML = "invalid url";  return false; } }


How can I get the exit code from command exec ?  This is the sample code. For the others commands it works but not for exec.  exec "somethings" if [ $? == 0 ]; then     echo -e "Done\n"     exit 0 else     echo -e "error\n"     exit 1 fi


How do I find the position of a word in a list using a function?

I know this question was asked many times on here, but could not find an adequate answer. I need to find the position of the words in a list, when I run my code it gives me None Here is the code: words = ['Banana', 'Banana', 'Apple', 'Apple', 'Pear', 'Peach', 'Grapefruit', 'St', 'Apple']  def get_position(words, type_word):     for idx, value in enumerate(words):         if value in words == type_word:             return idx           positions = get_position(words, 'Apple') print(positions)  Preferred Output: [2, 3, 8]


I have a tar that was generated on a linux machine. I need to upload part of that tar to another linux machine. The full tar is huge and will take hours to upload. I am now on a Mac OSX machine and this is my problem:   I extract the tar to a folder and locate what I need to upload to the new server I create a smaller tar containing just what I want to upload. I upload and extract that to the new linux machine When I look the server it is full of ._ files. For every file uploaded there is a ._ file, like text1.txt, ._text1.txt, text2.txt, ._text2.txt...   OSX is including these files on the tar.  I have tried to do this  tar --exclude='._*' -cvf newTar  .    without difference.   I do not have ssh access to the new server now.  What can I do to solve that? How do I generate a clean tar.


How do I stop my computer name from automatically, and incorrectly, changing?

Ever since I upgraded my 2009 iMac to Mavericks, I often get a message stating 'The name of your computer "Foo" is already in use on this network. The name has been changed to "Foo (2)".'. The number at the end will continuously increment over time as the same error keeps happening.  It is trivial enough to rename the computer back, but is there a way to prevent this from happening in future? I had an old Macbook Pro (running Mountain Lion) that had the same issue, but my early 2013 MBP running Mavericks doesn't seem to be suffering from this issue.


I have a bicycle frame that is not stamped and I can't figure out how to identify the brand of it

Serial number EY121000136 it's a 20 inch bmx bicycle


How to find where browser breaks a paragraph of text

I need to add line breaks in the positions that the browser naturally adds a newline in a paragraph of text.  For example:
This is some very long text \n that spans a number of lines in the paragraph.
  This is a paragraph that the browser chose to break at the position of the \n  I need to find this position and insert a
  Does anyone know of any JS libraries or functions that are able to do this?  The only solutuion that I have found so far is to remove tokens from the paragraph and observe the clientHeight property to detect a change in element height. I don't have time to finish this and would like to find something that's already tested.  Edit: The reason I need to do this is that I need to accurately convert HTML to PDF. Acrobat renders text narrower than the browser does. This results in text that breaks in different positions. I need an identical ragged edge and the same number of lines in the converted PDF.  Edit:  @dtsazza: Thanks for your considered answer. It's not impossible to produce a layout editor that almost exactly replciates HTML I've written 99% of one ;)  The app I'm working on allows a user to create a product catalogue by dragging on 'tiles' The tiles are fixed width, absolutely positioned divs that contain images and text. All elemets are styled so font size is fixed. My solution for finding \n in paragraph is ok 80% of the time and when it works with a given paragrah the resulting PDF is so close to the on-screen version that the differences do not matter. Paragraphs are the same height (to the pixel), images are replaced with high res versions and all bitmap artwork is replaced with SVGs generated server side.  The only slight difference between my HTML and PDF is that Acrobat renderes text slightly more narrowly which results in line slightly shorter line length.  Diodeus's solution of adding span's and finding their coords is a very good one and should give me the location of the BRs. Please remember that the user will never see the HTML with the inserted BRs - these are added so that the PDF conversion produces a paragraph that is exactly the same size.  There are lots of people that seem to think this is impossible. I already have a working app that created extremely accurate HTML->PDF conversion of our docs - I just need a better solution of adding BRs because my solution sometimes misses a BR. BTW when it does work my paragraphs are the same height as the HTML equivalents which is the result we are after.  If anyone is interested in the type of doc i'm converting then you can check ou this screen cast:    Edit: Many thanks to Diodeus - your suggestion was spot on.   Solution: for my situation it made more sense to wrap the words in spans instead of the spaces.  var text = paragraphElement.innerHTML.replace(/ /g, ' ');  text = ""+text+""; //wrap first and last words.  This wraps each word in a span. I can now query the document to get all the words, iterate and compare y position. When y pos changes add a br.  This works flawlessly and gives me the results I need - Thank you!


I've read about it, checked a few youtube videos about the subject but I still can't understand the process.  What is it that makes high voltage + AC current a better process to transport energy? I have seen formulas, but I need to understand how it works conceptually first.  If we use High Voltage (to cope with the resistance over a long distance) together with DC current a lot of energy is lost due to the continues resistance and the same happens with AC, so how is that one is better that the other one?  The only difference I can see, is the relief on the cables because of the polarity switch, is that why AC is better to transport electricity over long distances? Please don't use formulas to explain it, I need to understand how it all works first.  And if the voltage is higher how can the current be lower? I mean, there's a stronger force to push the electrons, so shouldn't it be the opposite?


Error Using OpenLayers 3 Web mapping applications

As being new to web site development, I have been able to display map on my website, but I want that I should only zoom to some specific places of India on loading of web pages.  Can somebody please suggest on how to go about it.  <!doctype html>   <meta charset="utf-8"> <title>Web Urban Atlas</title> <link type= text/css rel = stylesheet href="urban_stylesheet.css" /> <link rel="stylesheet" href="http://code.jquery.com/ui/1.11.2/themes/smoothness/jquery-ui.css">

Urban Atlas

Bangalore

Bangalore is city of gardens

delhi

Content for Delhi

mumbai

Content for Mumbai


Great books on all different types of integration techniques

It's coming up to Christmas so I can ask to have all the books I can't afford from begrudging relatives! I'm really interested (mainly from looking at some of the answers cleo and other fantastic users!) in being able to approach integrals from a variety of different ways and learning how to tackle  non-elementary integrals.   I've gone over a lot of the standard techniques in my undergrad and this is just for a hobby, so don't want anything too 'heavy', just great explanations and a lot of questions to tackle. So far I've found Irresistible Integrals: Symbolics, Analysis and Experiments in the Evaluation of Integrals. Many thanks.


I have $\displaystyle\sum_{n=0}^{\infty}\frac{n}{n+1}x^n$, for x$\in$R. Then I have to find the sum function. I know there is many ways to find the sumfunction. But can I  differentiate with respect to x and then find the sum of it? Then I have the differentiabel version of the sum function? Then I can take the integral from 0 to $\infty$?


proving a function is continuous, $f(x)=x^5 + 2x^3 + 3x^2 + 6$

let $f: \Bbb R \to \Bbb R $ be defined by $f(x) = x^5 + 2x^3 + 3x^2 + 6$  Prove that function is continuous?  I am just stuck on the first step how to manipulate the function algebraically and then I can apply the $\epsilon - \delta$ definition. Any hints on how to that?? Thanks in advance!!


Prove that $G$ is an abelian group if $\{(g, g):g\in G\}$ is a normal subgroup.

Let $G$ be a group and let $D=\{(g, g):g\in G\}$. If $D$ is a normal subgroup of $G\times G$, prove that $G$ is an abelian group.  My attempt:  $D$ is a normal subgroup of $G\times G$.  $\implies(a, b)D=D(a, b)\ \forall(a, b)\in G\times G$  So for a given $(a, b)\in G$ and $(g, g)\in D$, $\exists(g', g')\in D$ such that  $(a, b)(g, g)=(g', g')(a, b)$  $(ag, bg)=(g'a, g'b)$  $ag=g'a$ and $bg=g'b$  I feel like I've used all of the information given but don't know how to conclude that $G$ is abelian. Any suggestions?


Non-virtual vs virtual function call efficiency in C++

Reading about virtual functions, I have come across the following concept: "C++ non virtual function calls are resolved at compile time with static binding, while virtual function calls are resolved at runtime with dynamic binding."  My questions are: 1)Would it have a large effect on performance then, if we had a large number of virtual function calls in our program, since they are evaluated at runtime? Or is it not that relevant in modern machines?  2)Is that number dependent on the stack?


Is there a way to select a point from my map's current extent? I want to use ArcObjects to tell me if there is at least one point visible in my extent. I'd like to do this entirely in VBA, and without selecting any features or using any mouse-click events. (Selection can be done programmatically, just not manually.)  An demonstration would show that I have a point-type shapefile active and positioned at the top of my Table of Contents. I run my code which then displays a message box showing the longitude and latitude of the first point that is found within the current extent. Any point can be found and it's coordinates returned, just as long as that point is within the given extent.


How do I measure the variability in time time-series power consumption patterns?

Figure 1: X-axis represents the time (0-23 hours) and Y-axis represents the electricity consumption in kWh. I am working with time-series power consumption data. Figure 1 shows the shapes of one user on Wednesday, Thursday and Friday. All the shapes look different that indicates the stochastic behavior of that user. I want to measure this variability in load shapes. My ultimate goal is to quantify the difference in consumption patterns across days. What kind of statistical techniques I can use for the same? Is there any library/package available in python/R?  Please help me in this regard.


How to calculate $5^{2003}$ mod $13$   using fermats little theorem  5^13-1  1 mod 13  (5^12)^166+11 mod 13  a+b modn=(a modn + b modn) modn  (1+11mod13)mod13  12 mod 13 = 12  why answer is 8 ?   how do we calculate this  thanks


multiple regression and multiple comparisons

Say I fit a multiple regression of p explanatory variables. The t-test will allow me to check if any single one of those is significant ($H_0: \beta_i = 0$). I can do a partial F-test to check if some subset of them is significant ($H_0: \beta_i=\beta_j=...=\beta_k=0$).  What I often see though is that someone gets 5 p-values from 5 t-tests (assuming they had 5 covariates) and only keeps the ones with a p-value < 0.05. That seems a bit incorrect as there really should be a multiple comparison check no? Is it really fair to say something like $\beta_1$ and $\beta_2$ are significant but $\beta_3$, $\beta_4$ and $\beta_5$ are not?   On a related note, say I run 2 regressions on 2 separate models (different outcome). Does there need to be a multiple comparison check for significant parameters between the two outcomes?  Edit: To differentiate from the similar question, is there any other interpretation to the p-values besides: "B_i is (in)significant, when adjusting for all the other covariates"? It doesn't seem that this interpretation allows me to look at every B_i and drop those less than 0.5 (which is similar to the other post).   It seems to me that a sure fire way to test whether B_i and Y have an a relationship would be to get a correlation coefficient p-value  for each covariate and then do a multcomp (although that would definitely lose signal).  Finally, say I computed the correlation between B1/Y1, B2/Y1 and B3/Y1  (thus three p-values). Unrelatedly, I also did a correlation between T1/Y2, T2/Y2, T3/Y2. I'm assuming the correct Bonferroni adjustment would be 6 for all 6 tests together (rather than 3 for the first group and 3 for the second group - and thus getting 2 "semi"-adjusted p-values).


UNIX rename command, trying to rename some bulk files in a folder

trying to rename some bulk files in a folder  mv ~/folder/subfolder/filename.rpt ~/folder/subfolder/filename_sunset.rpt  is there any command, to do this to all together?


Omitting the last "to" in "All {I need to / have to / must} do is (to?) do something"

I remember I learned a structure like the one that this post’s title mentions:  All I {need to do | have to do | must do} is do something.  But is it correct to use "to do something"  after the "is" —  as compared with just plain "do something" without the "to"? Or to be more specific, which of the following sentences in each pair is correct, or are both version correct?  The second one in each case adds "to" to the formula:  Pair #1:   All I must do is prepare myself for the test.  All I must do is to prepare myself for the test.     Pair #2:   What we should do is teach children how to think. What we should do is to teach children how to think.    As far as I could remember, both forms should be fine.  But it seems that all the materials, texts, and articles I've read so far use the first form only. Furthermore, I'd really appreciate it if you could show me some references, like webpages or some book, where I could find more information about this point.


When to use high iso and a short shutter time and vice versa?

In what situations you can use a high iso value and a short shutter time, or use a low iso value and a long shutter time? What will be the difference between two pictures of exactly the same scene, when you take one picture with a high iso value and a short shutter time and another picture with a low iso value and a long shutter time?


Same Calculation giving different answer in different device

I wonder if i try this calculation on scientific calculator, i am getting 6/2(2+1) = 1   and in mobile device, online and normal calculators it gives me,  6/2(2+1) = 9   from my knowledge and what i get taught, first one (answer = 1) was correct... but how normal calculator provide this? i am confused. please clarify..  i searched about this, found something called BODMAS rule was the reason for first one.. is it correct or anything else?


Extracting peaks from DEM and creating 5 m elevation buffer around each peak in ArcGIS Desktop?

I have a DEM available and would like to identify all the peaks that are likely to be bare rock. I want to be able to isolate these areas and create a 5m elevation buffer around them to represent the non-productive forest. I have used tools like fill but find the output to be to large/general and would like to get more specific..    In summary, I want to find and extract each peak in the DEM to turn it into a polygon out to the closed contour that encompasses the peak. Ideally like the picture attached.


Are functors that are right-cancellable full, or do they have other characterizations?

In a  it has become clear to me that a functor is left-cancellable if and only if it is injective on morphisms. This provides a nice characterization of monomorphisms in category ${Cat}$.   I would like to know whether there is also a nice characterization for epimorphisms in that category. I allready found out that functors that are surjective on morphisms are right-cancellable, but also that the opposite of this is not true. Are there any 'weaker' conditions then? Are these functors necessarily full for instance? Uptil now I couldn't manage to find that out, so my first question is:     Are functors that are right-cancellable necessarily full?   More generally my second question is:     What characteristics can be mentioned of a functor that is right-cancellable?


Proving $1^3+ 2^3 + \cdots + n^3 = \left(\frac{n(n+1)}{2}\right)^2$ using induction

How can I prove that     $$1^3+ 2^3 + \cdots + n^3 = \left(\frac{n(n+1)}{2}\right)^2$$    for all $n \in \mathbb{N}$? I am looking for a proof using mathematical induction.  Thanks


I'm trying to vertically and horizontally align a login div for my Web App, but am having some trouble as I'm rather inexperienced using CSS. I've attached an image of what it looks like on the page, as well as my HTML and styles of the div taken from the Web Dev Tools to see if anyone can help out. For some reason the login div is not being centered horizontally although it appears to be close, and I've tried a few things with the vertical alignment but they haven't worked either. Thank you in advance for any suggestions. <c:url var="loginUrl" value="/login" />

                      <c:if test="${param.error != null}">
Incorrect username or password
             </c:if>

User Login

                          <form method="post" action="${loginUrl}" class="login-form">                                              <input type="hidden" name="${_csrf.parameterName}" value="${_csrf.token}" />
                             <input type="text" name="username" placeholder="Username"                                 class="form-control" />

                             <input type="password" name="password" placeholder="Password"                                 class="form-control" />

                             <button type="submit" class="btn-primary float-right">Sign In</button>
                     </form>

       text-size-adjust: 100%; -webkit-tap-highlight-color: transparent; --blue: #007bff; --indigo: #6610f2; --purple: #6f42c1; --pink: #e83e8c; --red: #dc3545; --orange: #fd7e14; --yellow: #ffc107; --green: #28a745; --teal: #20c997; --cyan: #17a2b8; --white: #fff; --gray: #6c757d; --gray-dark: #343a40; --primary: #007bff; --secondary: #6c757d; --success: #28a745; --info: #17a2b8; --warning: #ffc107; --danger: #dc3545; --light: #f8f9fa; --dark: #343a40; --breakpoint-xs: 0; --breakpoint-sm: 576px; --breakpoint-md: 768px; --breakpoint-lg: 992px; --breakpoint-xl: 1200px; --font-family-sans-serif: -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans",sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol","Noto Color Emoji"; --font-family-monospace: SFMono-Regular,Menlo,Monaco,Consolas,"Liberation Mono","Courier New",monospace; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"; font-size: 1rem; font-weight: 400; line-height: 1.5; color: rgb(33, 37, 41); text-align: center; box-sizing: border-box; flex-wrap: wrap; margin-right: -15px; margin-left: -15px; vertical-align: middle; display: inline-block; width: 35%;


Is it correct to use comma in this sentence?

Along the coast of northern California grow huge, towering trees. Why the comma is between huge and towering?


This error hinders me alot from taking actions like installing anything that requires the use of terminal.. E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing? i have tried to fix the missings with its command..   Each time i try to install git, this is always the result Reading package lists... Done Building dependency tree        Reading state information... Done Package git is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'git' has no installation candidate    Please help me, i use Ubuntu 19.04


I cannot get the key off of Neloth at Tel Mithryn that would allow me to get the black book from his locked room. I think my game has a glitch. I am playing on PS3.


Inconsistent loading symbols / design when refreshing feed

As seen in the screenshot below:   left: triggered by clicking the Feed menu at the left bar right: triggered by Pull to Refresh in the feed


Find a function in $L^p(\mathbb{R})$ only for $p=4$

I'm having trouble with this problem from an old analysis qual:  Find a function $f$ such that for $p\in (1,\infty)$, $f$ is in $L^p(\mathbb{R})$ only when $p=4$.


This relates to  Thanks for the advice in the answer of above mentioned question! I have a problem installing mysql and tried the solution, but it won't deinstall mysql-server-8.0: dpkg: error processing package mysql-server-8.0 (--remove):  package is in a very bad inconsistent state; you should  reinstall it before attempting a removal dpkg: too many errors, stopping Errors were encountered while processing:  mysql-server-8.0 Processing was halted because there were too many errors. E: Sub-process /usr/bin/dpkg returned an error code (1)  I can't install it either, because I get an error message as well. When I do sudo apparmor_parser -R /etc/apparmor.d/usr.sbin.mysqld  I get the following error message: AppArmor parser error for /etc/apparmor.d/usr.sbin.mysqld in /etc/apparmor.d/usr.sbin.mysqld at line 83: Could not open 'local/usr.sbin.mysqld'  I already tried the things mentioned in  And this one:  Can anyone help me get mysql installed?


Is it possible to have a key function as itself when used alone, and as another when used in combination

For example, can I make Space + J act as Ctrl + J, and Space act as Space when pressed on its own?


Generic method with multiple constraints

I have a generic method which has two generic parameters. I tried to compile the code below but it doesn't work. Is it a .NET limitation? Is it possible to have multiple constraints for different parameter?  public TResponse Call<TResponse, TRequest>(TRequest request)   where TRequest : MyClass, TResponse : MyOtherClass


Bizarre variable behavior in `while` loops

Can someone explain to me what's going on here?  Script:  #!/bin/sh SKIP="unity-launcher|unity-panel|unity-dash|Hud|XdndCollectionWindowImp|Desktop" WINS=() wmctrl -l | grep -Ev " (${SKIP})" | cut -d \  -f 1 | while read window; do     WINS=( ${WINS[@]} $window )     echo "Found window: $window; New size: ${#WINS[@]}" done echo "Total window count: ${#WINS[@]}" echo "Window IDs:" for i in "${WINS[@]}"; do     echo "  $i" done   Output:  Found window: 0x0380000a; New size: 1 Found window: 0x038002ae; New size: 2 Found window: 0x03800a33; New size: 3 Found window: 0x03000001; New size: 4 Found window: 0x04c00004; New size: 5 Total window count: 0 Window IDs:   Expected:  Found window: 0x0380000a; New size: 1 Found window: 0x038002ae; New size: 2 Found window: 0x03800a33; New size: 3 Found window: 0x03000001; New size: 4 Found window: 0x04c00004; New size: 5 Total window count: 5 Window IDs:     0x0380000a     0x038002ae     0x03800a33     0x03000001     0x04c00004   Essentially, at the end of the while loop, the WINS array is getting reset somehow, and I have no idea why.  Is there some weird scoping thing in bash I'm unaware of?


Remove shadow on frametitle,no theme used,personal customization

\documentclass{beamer}     \setbeamertemplate{navigation symbols}{}     \usepackage[utf8]{inputenc}     \usepackage[english,greek]{babel} %βαζω την ελληνική γλώσσα...όλα θα γινουν ελληνικα αν δεν χρησιμοποιήσω το \en     \usepackage{alphabeta}     \usepackage{multicol}     \newcommand{\en}{\selectlanguage{english}}  \newcommand{\gr}{\selectlanguage{greek}}     \author{\textlatin{e-M@th Team}}     \usepackage{array,amsmath}     \usepackage{amsthm}     \usepackage{lipsum}     \usepackage[T1]{fontenc} \definecolor{UniBlue}{RGB}{83,121,170} \definecolor{frame}{RGB}{2,0,0} \definecolor{LightBlue}{RGB}{153,187,255} \definecolor{Warm}{RGB}{230,76,0} \definecolor{BlockBackground}{RGB}{255,195,77} \definecolor{BackgroundCanvas}{RGB}{255,221,153}      \setbeamercolor*{frametitle}{fg=frame}       \useoutertheme{shadow} \usepackage{tikz} \usetikzlibrary{shadings} \colorlet{titleleft}{red!75!black} \colorlet{titleright}{Warm}    `  \makeatletter \pgfdeclarehorizontalshading[titleleft,titleright]{beamer@frametitleshade}{\paperheight}{%     color(0pt)=(titleleft);     color(\paperwidth)=(titleright)} \makeatother    `  \setbeamercolor*{author in head/foot}{fg=frame} \setbeamercolor*{title in head/foot}{parent=palette secondary,bg=} \setbeamercolor*{date in head/foot}{parent=palette tertiary,bg=}      \setbeamercolor*{background canvas}{bg=BackgroundCanvas} \makeatletter \setbeamertemplate{footline} {     \leavevmode%     \setbox\beamer@tempbox=\hbox{%         \begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.5ex,dp=1ex,center]{author in head/foot}%             \usebeamerfont{author in head/foot}\insertshortauthor\expandafter\beamer@ifempty\expandafter{\beamer@shortinstitute}{}{~~(\insertshortinstitute)}         \end{beamercolorbox}%         \begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.5ex,dp=1ex,center]{title in head/foot}%             \usebeamerfont{title in head/foot}\insertshorttitle         \end{beamercolorbox}%         \begin{beamercolorbox}[wd=.333333\paperwidth,ht=2.5ex,dp=1ex,right]{date in head/foot}%             \usebeamerfont{date in head/foot}\insertshortdate{}\hspace*{2em}         \end{beamercolorbox}%     }%     \beamer@tempdim=\ht\beamer@tempbox%     \advance\beamer@tempdim by 4pt%     \begin{pgfpicture}{0pt}{0pt}{\paperwidth}{20pt}         \pgfpathrectangle{\pgfpointorigin}{\pgfpoint{\paperwidth}{\beamer@tempdim}}         \pgfusepath{clip}         \pgftext[left,base]{\pgfuseshading{beamer@frametitleshade}}     \end{pgfpicture}     \vskip-\beamer@tempdim%     \box\beamer@tempbox%     }%    `  \setbeamercolor*{block title}{fg=frame,bg=Warm}  \setbeamercolor*{block body}{fg=frame,bg=BlockBackground}   \setbeamertemplate{frametitle continuation}{}     \setbeamertemplate{blocks}[rounded]{}      \date{} \title{}   \begin{document}          \begin{frame}{}     \frametitle{Οι πραγματικοί αριθμοί}       \begin{block}{παραδειγμα τιτλος}         παραδειγμα προταση \newline τι \\ θα γινει \\ αν ειναι\\ πολυ \\ μεγαλο \\ το \\ παραδειγμα \\ ;; \\ ;; \\ ;;      \end{block} \end{frame}  \end{document}     `


After a few years of university mathematics I just realised that I do not really know the difference between an axiom and a definition. With some "research" on the interwebs (, ). I think that axioms are definitions that build the foundation of a Theory. E.g. we have group axioms because we build a theory on them. But they are nothing else than a definition and we can check if some object satisfies the axioms/definition to be a group. Lets look at continuity. Its a definition that says when we call a function continuous. We can check if that is the case or not. Its not called an axiom because we first need to define other things to get to continuity, like topology or metric spaces. There can be multiple equivalent definitions, which is the case with continuity. What do you think? Is that a somewhat accurate understanding of the terms?


Checking file count for a particular format in a directory in unix

I want to know the file count for a particular format like .txt in a particular directory


Bake to keyframes messes up cell fracture

I am making a short animation of a sphere breaking a window with cell fracture.  Here is how it looks mid-break:    I thought it looked good so I decided to bake it into keyframes to upload it to the sheepit renderfarm. I selected them in the outliner with box select and then right clicked > select. Then I clicked bake to keyframes in the rigid body tools.    When I bake it, the sphere bakes fine, but the cell fracture pieces end up all squished looking like this:    Anyone know why this is happening? Is there a solution to this problem?  Additional info:   The cell fracture pieces all share the same animation data. I animated the 'Dynamic' property in order to delay the animation until needed.  To clarify, I selected all cell fractured objects at the same time.


Can I have a path argument that contains spaces?

I'm trying to get biblatex to see where I have my .bib file located, but I have a space in the path to the file:  \addbibresource{~/Documents/My Project/TheBib.bib}   How do I specify a full path that includes a space? Is there a way to ?    M(Not)WE, as requested:  \documentclass[nobib]{tufte-handout}  \usepackage{hyphenat}  \usepackage[backend=bibtex, natbib=true, citestyle=verbose]{biblatex} \addbibresource{~/Documents/Projects/NoSpaces/Sources.bib} % Works %\addbibresource{~/Documents/Projects/Some Spaces/Sources.bib} % Fails %\addbibresource{"~/Documents/Projects/Some Spaces/Sources.bib"} % Fails  \begin{document}  Test.\cite{CiteKey}  \printbibliography   \end{document}


Centos7 can't boot with shim-x64-15-7.el7_9.x86_64


What is Ubuntu Touch (Ubuntu for Phones)

Following up on Canonical's announcement, what is , where can I download a copy of the OS to run on my phone? And how do I know if it's compatible with my phone?


Google news not showing images from my site

I have a question for you. One of the sites I'm working on has been accepted in Google news. Now, my issue is that most of the time,no image is fetched, while some other times a related image from another website is shown instead.  I have read somewhere that the image needs to be nearby or in the title tag - is it so?  Any idea what I am doing wrong?


How can you prove $ \left ( 1 + \frac{1}{k} \right ) ^ {k} < \left ( 1 + \frac{1}{k+1} \right ) ^ {k+1} $

I'm re-reading my old math books, and froze on the following theorem:  $$ \lim_{x\to\infty} \left ( 1 + \frac{1}{x} \right ) ^ {x} = e $$ $$ e = 2,71... $$  I started thinking about it, and went on to prove:  $$ \left ( 1 + \frac{1}{k} \right ) ^ {k} < \left ( 1 + \frac{1}{k+1} \right ) ^ {k+1} $$  ..but couldn't.  Please help.


Minecraft Bedrock Edition: Give lever that can only be placed on a specific block

In my Minecraft world I am building a map and in this map I need to be able to give the player a lever that can be placed on only one block of my choice (like a gold block for instance).  I tried these commands in a command block  give @p lever 1 0 {CanPlaceOn:[“gold_block”]} give @p lever 1 0 {CanPlaceOn:[“minecraft:gold_block”]} give @p lever 1 0 {CanPlaceOn:[gold_block]} give @p lever 1 0 {CanPlaceOn:[“Block:gold_block]}   All of them give me an error at the syntax past the CanPlaceOn:[ (copy/paste them into your world and you’ll see what I mean).  What am I doing wrong? I've checked all over the internet and it seems there aren’t any really clear guides on how to do this (and I know it can be done because there is a map on  that is called “Escape!” and you get a lever that can only be placed on gold blocks).


Usage of the colon in this sentence (and alternatives)

Is the colon used in the following sentence correct? If so, would it be better to replace it with a semicolon or a period?     As CPUs get faster and faster, it is important that the performance of the memory system keeps pace: otherwise, the speed of the overall system will be compromised by the memory system bottleneck.


Is there a way to rename all files in a directory?

Ubuntu 16.04  I'm pretty new to linux and have a large number of files an the directory dir. These files have postfix _uploaded.   Is there a way to rename all this files and set them postfix _handled instead of _uploaded?


If $\mathrm{char}(K)=p$ is prime, $L/K$ is separable if and only if $K(\alpha) =K(\alpha^p)$ for all $\alpha \in L$

I am trying to prove that if $L/K$ is an algebraic extension and if $\alpha \in L$, then    $\alpha$ is separable over $K$ if $\mathrm{char}(K)=0$. This is clear because $K$ is perfect which in turn implies that $L/K$ is seperable .  Now if $\mathrm{char}(K)=p$ is prime, then the statement is: $\alpha$ is separable if and only if $K(\alpha) =K(\alpha^p)$.  This problem is from a past examination and looks very interesting, but somehow I am not able to connect what's happening with the extension of $K$ with $\alpha$ and $\alpha^p$ .   I need some help here.    This somehow makes me think that the minimal polynomial of $\alpha$ and $\alpha^p$ have different roots and $\alpha$ is given by some root of minimal polynomial of $\alpha^p$ .   Note that I am using the definition of separability as follows :      An extension $L/K$ is called separable if for every $\alpha \in L$ the minimal polynomial of $\alpha$ has distinct roots in $L$ .    Thanks for helping.


Calculate the leading order asymptotic behaviour (with two maxima)

thanks in advance!  Calculate the leading-order asymptotic behaviour of the integral $$I(x) = \int_{0}^{2\pi} (1+t^2) e^{x \cos t} dt \mbox{ as } x \mbox { tends to infinity}$$  So far I know there are two maximas at $0 \mbox{ and }2\pi$ so it can be assumed to be the integral  $$\int_{0}^{\epsilon} (1+t^2) e^{x \cos t} dt + \int_{2\pi-\epsilon}^{2\pi} (1+t^2) e^{x \cos t} dt$$ then using taylor expansions this can be transformed to: $$\int_{0}^{\epsilon} (1+t^2) e^{x (1-\frac{t^2}{2})} dt + \int_{2\pi-\epsilon}^{2\pi} (1+t^2) e^{x (1-\frac{1}{2}(t-2\pi)^2)} dt$$ but where do I go from here? How do I find the leading order term?


How to make citations appear within parentheses () instead of square brackets [ ]?

I am using the vancouver.bst which conforms to the ICMJE (international committee of medical journal editors) How do I make the citations in the text appear in parentheses, e.g., (3), rather than in brackets [3]?


What does the permission string lrwxrwxrwx mean?

when I cd to / and enter the command:  ls -ls   For some files/folders it gives output like  0 lrwxrwxrwx.   1 root   root         7 Jan 30  2018 bin -> usr/bin   So what actually is this lrwxrwxrwx?


Do United States green card holders need a visa to re-enter the US from Iran?

I am a US citizen but my wife is an Iranian citizen with US permanent resident status, which she obtained through our marriage. We were planning to travel to Iran to visit my in-laws. However, we are worried, , that there will be problems for us and that she will not be able to re-enter the US without a visa.   Will she be able to re-enter the US without having to apply for a visa?  Update: Just wanted to update this question with our experience. We were able to go to Iran and come back without any problems. As the answers to this question pointed out, the green card lets you return and the changes to the Visa Waiver Program has no impact if you are a permanent resident.


For a a positive integer $n$, let $d(n)$ denote the number of divisors of $n$. I'm trying to prove that:   1) For $n>6$ we have $d(n)\leq\frac{n}{2}$;  2) For $n>12$ we have $d(n)<\frac{n}{2}.$  Can someone help me?


Creating new feature classes from rows in polygon feature class?

I'm trying really hard here to get an arcpy equivalent for ARCGIS' ModelBuilder's Iterate Feature Selection. I need to export the individual polygon rows in a feature class as new feature classes.  Any help?


I have a material assigned to a few test objects with an image sequence as a texture. If I view the scene in render preview, and scrub the timeline, (or render a sequence,) the texture behaves as expected.  However, with the viewport set to 'texture' or 'material' I only see the first frame of the sequence, wherever I am on the timeline. 'Auto Refresh' is set in the cycles texture node. Is this the expected behaviour?


I've just read a couple of questions concerning the proper usage of the pronouns "I" and "me" in sentences like:     John and I went fishing   It seems clear and obvious to me, that when the pronoun is the subject of the sentence, we should use the subject pronoun.   My question concerns a different context, though. I'm curious as to which pronoun is correct when used in a short, one-word answer? So, when we hear a question like "Who wants to go fishing tomorrow?", should the answer be:     Me!   or     I!   My intuition tells me it should be the former, but I don't really know why. Is there any underlying rule in English, that dictates which pronoun - subject or object - should be used in the above-mentioned context?


Why shouldn't photons be able to curve spacetime?

I have read  question. It was asked if photons are able to curve spacetime. But if classical electromagnetic fields can curve spacetime (due to the energy contained in the fields contributing to the mass-momentum tensor) why shouldn't photons be able to do this? If the em field curves spacetime then photon fields should be able too. After all, they constitute the classical em field when the number of photons is large. I mean, what would be the reasons to ask if a photon would not be able to make spacetime curve? One thing I can think of (thanks to @WolphramJohnny): a photon has a different energy in different frames of reference, so if it curves spacetime in one frame it curves spacetime differently (more or less) in different frames of reference. This holds true also for massive particles but massive particles have a rest mass, while photons have not, so curvature due to mass is not there. Only curvature due to motion, which gives rise to linear frame-drag. Though this can also be said for classical em waves. So photons must emit gravitons (or small spacetime distortions) like a speeding boat emits bow waves (if it speeds. But how can this be different for different frames? In one frame the photon will not even emit gravitons (no energy). Can we say that photons can't exist in General relativity in the first place (because they are a quantum object)? Can only fermions emit gravitons (because they are quantum objects)? Of course, you can say that we need a quantum theory of gravity (which doesn't necessarily mean that gravitons are involved though; spacetime itself can also be seen as quantized) but the theory has to involve an interaction with a graviton field.


What, if any, experimental evidence is there that flies rub their legs together in order to clean them?

Everybody's seen a fly  like Mr Burns. And almost everybody's heard the standard explanation - that it's cleaning itself. Now, this is certainly a very plausible explanation, but has it been demonstrated? I can't find any references to experiments seeking to prove this hypothesis. I'm asking because, not being very familiar with these matters, I'd love to know what methods were used to demonstrate something like this.


Cannot run bash file for set up Hadoop path

I have a hadoopSetup.sh file for set up Hadoop in my computer: #!/bin/bash export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-amd64  export HADOOP_HOME=/usr/local/hadoop  export PATH=$PATH:$HADOOP_HOME/bin:$HADOOP_HOME/sbin  But I cannot execute this file with this command: $ chmod +x hadoopSetup.sh  $ sh hadoopSetup.sh  I don't know why but if I run the export command in the .sh file individually in the terminal, it works fine. $ export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-amd64  $ export HADOOP_HOME=/usr/local/hadoop  $ export PATH=$PATH:$HADOOP_HOME/bin:$HADOOP_HOME/sbin  Do you guys know how to run this file?


Saving bitmap in sharedpreferences, Out of memory

I am trying to save bitmap in sharedpreferences and restore it again in start-up. But it is working fine one time and if I close and restart the app it gives me "force close" error, and then if I run it again it works fine and again crashes and so on.  What is the problem?  My onActivityResult code is here:  @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) {     // TODO Auto-generated method stub     super.onActivityResult(requestCode, resultCode, data);      if (requestCode == GALLERY_PICTURE) {         if (resultCode == RESULT_OK) {                   Uri selectedImage = data.getData();                 String[] filePathColumn = {MediaStore.Images.Media.DATA};                  Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);                 if (cursor != null) {                 cursor.moveToFirst();                  int columnIndex = cursor.getColumnIndex(filePathColumn[0]);                 String filePath = cursor.getString(columnIndex);                 cursor.close();                  Bitmap photo_gallery = BitmapFactory.decodeFile(filePath);                img_logo.setImageBitmap(photo_gallery);                settings = getSharedPreferences("pref", 0);                SharedPreferences.Editor prefsEditor = settings.edit();                     prefsEditor.putString("photo1", filePath);                     prefsEditor.commit();                 }               } else {                 Toast.makeText(getApplicationContext(), "Cancelled",                         Toast.LENGTH_SHORT).show();             }         } else if (resultCode == RESULT_CANCELED) {             Toast.makeText(getApplicationContext(), "Cancelled",                     Toast.LENGTH_SHORT).show();         }      else if (requestCode == CAMERA_REQUEST) {         if (resultCode == RESULT_OK) {             String[] projection = { MediaStore.Images.Media.DATA};  Cursor cursor = getContentResolver().query(mCapturedImageURI, projection, null, null, null);       int column_index_data = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);              cursor.moveToFirst();              String capturedImageFilePath = cursor.getString(column_index_data);             Log.d("photos*******"," in camera take int  "+capturedImageFilePath);              Bitmap photo_camera = BitmapFactory.decodeFile(capturedImageFilePath);              if(data != null)             {                 img_logo.setImageBitmap(photo_camera);                 settings = getSharedPreferences("pref", 0);                 SharedPreferences.Editor prefsEditor = settings.edit();                     prefsEditor.putString("photo1", capturedImageFilePath);                     prefsEditor.commit();             }           }    }   }   in Log.d I get a lot of Red lines. but I think this is the problem:  02-24 11:12:07.026: E/AndroidRuntime(29791): FATAL EXCEPTION: main 02-24 11:12:07.026: E/AndroidRuntime(29791): java.lang.OutOfMemoryError: bitmap size exceeds VM budget(Heap Size=7235KB, Allocated=2862KB, Bitmap Size=8748KB)


I have two independent gaussian distributions to combine and I have a doubt.  Let's say we have $X \sim N(\mu_x,\sigma^2_x)$ and $Y \sim N(\mu_y,\sigma^2_y)$. I want to mix the two variables with a 0.5 weight each, so I obtain a new variable $Z=0.5*X+0.5*Y$ with mean $\mu_z=0.5*\mu_x+0.5*\mu_y$.  Is it right to say that $\sigma^2_z=0.5^2*\sigma^2_x+0.5^2*\sigma^2_y$?  Because I clearly obtain less variance than intuitively expected when combining distributions.


Can anyone please recommend me a good number theory book to read? I want lots of answers to get a good idea. I am a 1st year university student, so it would be good if there are no deep terms and the theory is explained well.


Why did King Bradley allow the Elric brothers, Hughes, and Armstrong to continue investigating the military?

In episode 10 of Full Metal Alchemist: Brotherhood, during the events in the Research Lab 5, Edward Elric is severely hurt. Later in the hospital, he writes down everything he had come to know, and he discusses with Alphonse, Hughes, and Armstrong about what to do with the information to continue the investigation.  At this point, King Bradley arrives with lemon into the room. He finds out what they are doing but acts very calm and chilled out and allows them to continue investigation while being careful.  Why did he not get Hughes and Armstrong killed at that point? Or at least tell them to not investigate at all?


I can't install Broadcom driver on Ubuntu 14.04

After installing Linux Ubuntu 14.04 on a new Lenovo V580c, I can't install Broadcom Wi-Fi adapter driver. After "Applying changes..." nothing happens.  lspci -nn | grep 0280  03:00.0 Network controller [0280]: Broadcom Corporation BCM43142 802.11b/g/n [14e4:4365] (rev 01)


The down key on my laptop is broken.  I want to map shift+up to down.  My original layout had (from xmodmap -pke)  keycode 111 = Up    NoSymbol Up keycode 113 = Left  NoSymbol Left keycode 114 = Right NoSymbol Right keycode 116 = Down  NoSymbol Down   To be on the safe side, let us set up+all mods to down:   keycode 111 = Up    Down Down Down Down Down   Indeed, xev shows keysym down when I press up while holding shift (xev output from pressing down, then shift+up is included below); but applications do not react properly (e.g., Firefox acts as to normal shift+up, in the terminal I get [1;2B which is different from unmodified shift+up ([1;2A)).  It does not work with other modifier combinations either.  I also tried keysym Down = Down Up as suggested , but that did not work either.    Edit for clarification: My approach and the answer to the linked question do not work for me because some applications (Firefox and Thunderbird for example) react to the re-mapped shift*down as if shift+up had been pressed, not up alone.  In addition, my terminal emulator prints [1;2B instead.  Alternatively, I tried remapping the left shift and control keys to down; this works in the terminal, but e.g. Firefox still responds as to shift+up or control+up, respectively.    xev output:  KeyPress event, serial 32, synthetic NO, window 0x1e00001,     root 0x80, subw 0x0, time 4024962, (-429,376), root:(215,396),     state 0x0, keycode 116 (keysym 0xff54, Down), same_screen YES,     XLookupString gives 0 bytes:      XmbLookupString gives 0 bytes:      XFilterEvent returns: False  KeyRelease event, serial 32, synthetic NO, window 0x1e00001,     root 0x80, subw 0x0, time 4025234, (-429,376), root:(215,396),     state 0x0, keycode 116 (keysym 0xff54, Down), same_screen YES,     XLookupString gives 0 bytes:      XFilterEvent returns: False  KeyPress event, serial 32, synthetic NO, window 0x1e00001,     root 0x80, subw 0x0, time 4027956, (-429,376), root:(215,396),     state 0x0, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,     XLookupString gives 0 bytes:      XmbLookupString gives 0 bytes:      XFilterEvent returns: False  KeyPress event, serial 32, synthetic NO, window 0x1e00001,     root 0x80, subw 0x0, time 4028076, (-429,376), root:(215,396),     state 0x1, keycode 111 (keysym 0xff54, Down), same_screen YES,     XKeysymToKeycode returns keycode: 116     XLookupString gives 0 bytes:      XmbLookupString gives 0 bytes:      XFilterEvent returns: False  KeyRelease event, serial 32, synthetic NO, window 0x1e00001,     root 0x80, subw 0x0, time 4028150, (-429,376), root:(215,396),     state 0x1, keycode 111 (keysym 0xff54, Down), same_screen YES,     XKeysymToKeycode returns keycode: 116     XLookupString gives 0 bytes:      XFilterEvent returns: False  KeyRelease event, serial 32, synthetic NO, window 0x1e00001,     root 0x80, subw 0x0, time 4028228, (-429,376), root:(215,396),     state 0x1, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,     XLookupString gives 0 bytes:      XFilterEvent returns: False


If you sequentially subtract a number from row to row, sometimes excel will get close to, but not 0, even though 0 is the right answer?  For example, if you start out with 1 and subtract 0.05 sequentially from the previous answer, you should eventually get to 0, but excel does not.  Sometimes this poses a problem in doing financial calculations.  Is there a setting that will convert these numbers to exact 0?  I am reluctant to use round() in that it may adversely impact the other numbers that I would like to have the appropriate level of precision.


Shell script to copy list of files with spaces

I am trying to create a small script that takes a filename, in which the absolute location of files are listed, and to copy it to some other location.   Content of the file test.txt for example:  /home/public/Music/Disk/GameOfThrones/Season1/01 Main Title.mp3   Script tried:   for file in `cat test.txt`; do cp "$file" temp ; done   However, this script thinks there are three files. Some more searching yield the following file:  OIFS="$IFS" IFS=$'\n' for file in `cat test.txt`; do cp "$file" temp ; done IFS="$OIFS"   which seems to replace each occurrance of the letter 'n' by a newline.   So how to do it correctly?


Counterexample for $\lim \limits_{x \to c} \left\lvert f(x) \right\rvert = \left\lvert L \right\rvert$ then $\lim \limits_{x \to c} f(x) = L$

I know that the converse of this is true. I was looking for some counterexamples proving this statement false.


In which situations should I use fish-eye effect? I own a Canon Power sx510hs which is an advanced point and shoot camera. It has fish eye effect which distorts an image spherically. Other than having funny photo sessions with my kin, I would like to know what are the main utility of this effect and how I can produce quality photographs using this effect.


Force fsck.ext4 on reboot, but really "forceful"

One of my Ubuntu 10.04 servers is giving me trouble. When I run fsck.ext4 -n /dev/sda5 it tells me there are errors in the free inode count, free block count, and more.  I have tried:  touch /forcefsck   Also tried:  shutdown -rF now   and still, after reboot, I see errors.  I also just checked on my eeePC netbook, Ubuntu 10.10, and have the same issue!  How can I force a really "forced" "forceful" "seriously fix my filesystem" fsck of the "/" filesystem on reboot?  Clarification: I run fsck.ext4 -n because it's a mounted filesystem, to check if there are errors. This tells me that there are. I thought that the automatic fsck every 30 mounts during the boot-up process is precisely to take care of errors in the root filesystem. But it doesn't do it in my case. I could reboot with a LiveCD and fix the errors, and then reboot again, but that's some serious downtime for a live server. A reboot, auto fsck, then continue booting is much more sustainable on a live server, and I believe should be the right behaviour.  Additional info: Here is the output. It looks like something that the autofsck would fix, doesn't it?  root@server:~# fsck.ext4 -n /dev/sda5 e2fsck 1.41.11 (14-Mar-2010) Warning!  /dev/sda5 is mounted. Warning: skipping journal recovery because doing a read-only filesystem check. /dev/sda5 contains a file system with errors, check forced. Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information Free blocks count wrong (1849368, counted=1948909). Fix? no  Free inodes count wrong (545504, counted=552134). Fix? no   /dev/sda5: ********** WARNING: Filesystem still has errors **********  /dev/sda5: 116752/662256 files (0.2% non-contiguous), 795324/2644692 blocks


I want to make a number appear in the hexadecimal alphabet but I don't know how.  For example I used the number  255.I wanted the number to appear as "FF FF" but it appear as "15 15"  number is the number I want to convert  base is the desired alphabet (bin,dec,oct,hex)  str is the table with the digits  digits is how many digits I have   # include <iostream> using namespace std; class Number {     private:         int number;          int base;         int str[80];         int digits;         void    convert();      public:         Number(int n);         Number(int n,int b);   printNumber prints the number          void    printNumber(); };   convert is the function that converts the number  void    Number::convert() {     int icount=0;     int x=number;     while(x!=0)     {         int m=x % base;         x=x/base;         str[icount]=m;         icount=icount+1;     }   digits count the number of digits I have      digits=icount; }   this function uses as base dec   Number::Number(int n) {     number=n;     base=10;     convert(); }   this function uses as base an integer b  Number::Number(int n,int b)  {     number=n;     base=b;     convert();  }  void    Number::printNumber() {     int i;     for(i=digits-1;i>=0;i--)       cout<<str[i]<<" ";      cout<<endl; }   int main() {     Number n1(255);     Number n2(254,16);     n1.printNumber();     n2.printNumber();     std::cout << "Press ENTER to continue...";     std::cin.ignore( std::numeric_limits<std::streamsize>::max(), '\n' );     return 0; }


Is hyperparameter tuning on sample of dataset a bad idea?

I have a dataset of 140000 examples and 30 features for which I am training several classifiers for a binary classification (SVM, Logistic Regression, Random Forest etc)  In many cases hyperparameter tuning on the whole dataset using either Grid or Random search is too costly time-wise.  I started using the following technique   Sub sample my dataset Use the obtained fraction to tune the hyperparameters on Use the obtained parameters to train a model using the whole dataset   To evaluate each set of parameters on the second step I use sklearn's GridSearchCV with cv=10. To evaluate the final model that I create in the third step I use sklearn's cross_val_predict. In that sense I evaluate my models leaving a 10% percent of data out, I train on the rest and measure the predictive accuracy on the 10%, iteratively 10 times, then taking the average of the scores.  What made me worry is that the prediction accuracy I get from training on my whole dataset, is really close to the evaluation I get when tuning the parameters for the best set of parameters (each tested set of parameters outputs a score obtained from averaging 10-fold-cross validation results).  Most of the times the accuracy that cross_val_predict measured using all the training examples (whole dataset) is a little bit above what the evaluation of the best parameters returned.  To illustrate this here is the evaluation of a set of parameters (on a smaller dataset than what I described above but the effect is the same)  Best parameters set found on development set: {'kernel': 'rbf', 'C': 9, 'gamma': 0.1} Scores for all sets of parameters 0.851 (+/-0.006) for {'kernel': 'rbf', 'C': 3, 'gamma': 0.5} 0.852 (+/-0.006) for {'kernel': 'rbf', 'C': 3, 'gamma': 0.1} 0.829 (+/-0.006) for {'kernel': 'rbf', 'C': 3, 'gamma': 0.001} 0.853 (+/-0.006) for {'kernel': 'rbf', 'C': 9, 'gamma': 0.1} ...   And here are the averaged scores (from cross_val_predict) I got from training on my whole dataset using the best parameters  precision    recall  f1-score   support        0       0.86      0.85      0.86     15417       1       0.86      0.87      0.87     16561  avg / total       0.86      0.86      0.86     31978  acc score: 0.863750078179 roc au score: 0.863370490059 [[13147  2270]  [ 2087 14474]]   As you can see training on the whole dataset improves the results. I have also validated that badly tuned model (e.g. using the default values or random values for C and gamma) leads to much worse prediction accuracy.   Overall I think that tuning the hyperparameters on a subset is not ideal but can potentially lead to relatively good results without having to wait too long. I for example before using that approach used optunity package for tuning the hyperparameter on the whole dataset. This procedure would take 3-5 days to complete and would produce results that either had really good precision or really good recall but not both, so although for each class either the precision or the recall was really high (higher than what any of my other classifiers had achieved) the f1 meassure was really low. In the contrary using the later approach leads to some hours of training and a better f1 meassure.   My concerns are:  Do I limit my classification accuracy? Do I avoid using all the prediction power that my dataset can offer by tuning only on a subset? If such a harm of performance is happening is it somehow limited by some factor?


/usr/bin/env: ‘awk -f’: No such file or directory

Linux shylock-archinux 4.15.15-1-ARCH #1 SMP PREEMPT Sat Mar 31 23:59:25 UTC 2018 x86_64 GNU/Linux  My machine is above.Anyone know what happend?  The script with shebang #! /usr/bin/env awk -f don't work?I call it by ./script.awk inputfile,it should be same as manually call awk -f ./script.awk inputfile,but only the latter work well!  which awk output /usr/bin/awk.


Plural/singular form for a company in American English?

a guy claims that in American English it's proper to use the singular form for conjugating the predicate of group terms such as company, band, team etc. In British English, he claims, it's more common to use the plural form for there.  My question is threefold.   Is it true that it's not the intended meaning that governs numerus? If so, how profoundly rooted is that difference in the dialects? If it is, how does one formulate the following in American English?      -- The diversity level amongst the people you've hired must be low?     -- No, our staff is/are actually quite different individuals.


Why product of primes $+1$ is not divisible by any of the product primes?

Given $n$ prime numbers, $p_1, p_2, p_3,\ldots,p_n$, then $p_1p_2p_3\cdots p_n+1$ is not divisible by any of the primes $p_i, i=1,2,3,\ldots,n.$ I dont understand why. Can somebody give me a hint or an Explanation ? Thanks.


I have a question about creating an excel chart with two Y axes. Suppose I have the following data:           Horizontal Axis    Primary Vertical Axis    Secondary Vertical Axis Series 1     1                    0.5                         5.7              2                    0.2                         6.3              3                    0.3                         6.2              4                    0.8                         4.8              5                    0.4                         4.2  Series 2     1                    0.3                         5.1              2                    0.5                         7.2              3                    0.2                         6.4              4                    0.6                         6.1              5                    0.4                         4.9   I want to create a scatter plot with two lines from the data above, where the primary vertical axis data is read on the left side of the graph and the secondary vertical axis data is read on the right.   The only information I have found is how to insert entirely new series' for the information that will be read from the secondary axis, but this is not what I want to do. If I did that I would end up with 4 lines on the chart (2 for the primary axis and 2 for the secondary axis). Instead, I only want to have 2 lines on the chart that read from both the primary and secondary vertical axis at the same time. In other words, each line should be plotted as having two independent variables (one for each vertical axis).  Thanks


Does IBIS reduce image resolution? How does it compare to lens based IS?

I heard a lot about in-body image stabilization recently and I wonder how this technology works. I don't mean the mechanical part (I understand how the sensor moves along different axes to compensate), but the technique in principle:  When I take my 5D III and a lens like the 70-200 2.8 II IS USM with activated stabilization, the IS will constantly move one glas element within the lens in such a way that it directs the cone of light exactly onto the sensor, so that you can always use the full sensor area.  When the cone of light goes through an unstabilized lens and you need to move the sensor - how can it capture the same amount of light at all? The light enters the lens down a fixed axis right through the center of the lens. When the sensor currently moves down, for example, to compensate for a shake, I can't see how it then is still able to capture the full resolution? When a part of the sensor is below default/calm position, then there must be missing the same part on the opposite site?  There's only one way I could image IBIS to work without resolution reduction: if the sensor area was significantly bigger than the area exposed to light, so that there's still sensor available when it currently moves out of its initial position. But wouldn't this (partly) be the same as digital stabilization because the final image gets calculated from the full sensor area minus the not exposed area?  I really would like to understand this and it would be great if someone could "shed some light on this".


note:  {"category_id":"1","name":"Notes","icon":"images\/note.png"}, quote:  {"category_id":"2","name":"Quotes","icon":"images\/quote.png"}, project:  {"category_id":"3","name":"Projects","icon":"images\/project.png"}, skill:  {"category_id":"4","name":"Skills","icon":"images\/skill.png"}   this is what is shown in my console. I have used json_decode for my query, and concatenated with string, and I believed that's the caused of the problem.    so how to turn string data into json format?


Check a point whether it is inside the square/rectangle/polygon in ObjectiveC

I's looking for simple(easy to implement algorithm) to check whether a point is inside the square/rectangle/polygon(convex)  I use CAShaperLayer to draw the polygon and I know there is hittest method in CAShaperLayer. For some reason, I don't allow to use hittest.  What I did so far:  I use a circle to approximate the polygon and check whether a point is inside the circle(choose three points and generate a circle since three point determine a circle). The approximate method works but it is not accurate.


Why not char/float/double (other primitive data types) be return type of main()?


12GB of RAM only 8GB is usable on Windows 7 64-bit

I'm running a Dell Studio XPS, with quad core processor, two threads per core, with 12GB of installed RAM. According to Windows, only 7.99GB of that RAM is usable.  The really weird part is, up until two weeks ago I only had 8GB of RAM and then only 3.99GB was usable. So 4GB of RAM is consistently being taken.  I've checked in every screen, under every option in my BIOS and there doesn't seem to be a memory option there at all (that's a damn Dell for you). I've read that a lot of times this can occur because of the video card stealing some RAM for itself.   Is there some way I can check this, other than the BIOS? I have onboard graphics, not a separate card.  I'm running Windows 7 64-bit.


Can't install any version of nodejs >10 (10,12,13) in my lubuntu

I typed following command on my lubuntu terminal from the nodejs download page to install 13.x version : curl -sL  | sudo -E bash - sudo apt-get install -y nodejs  but,when i checked the version of node it was showing me 8.x version.Even i tried to install all  the versions above 10.x ,but still the version was 8.x.Then i tried nvm to change version still the same version. The i tried using npm still the same problem. Actuall the problem is that Angularcli will only work on node versions above 10. Th


Can Windows OS be installed and then made read-only so that malware can be cleared by a reboot?  If so, how?  Can Windows be installed to a VM, then make all the underlying VM files read-only and still have Windows boot OK?  I used to have a CD with an old version Windows on it, and that did the trick (lost the CD ages ago).  I have a CentOS build from the DoD that works, but I'm not a Unix guy.


How can I parse dates and convert time zones in Perl?

I've used the  function in Perl to get the current date and time but need to parse in existing dates. I have a GMT date in the following format: "20090103 12:00" I'd like to parse it into a date object I can work with and then convert the GMT time/date into my current time zone which is currently Eastern Standard Time. So I'd like to convert "20090103 12:00" to "20090103 7:00" any info on how to do this would be greatly appreciated.


Existence & uniqueness of solutions of linear congruences $\ cx\equiv b\pmod m$

Prove that one can solve the congruence $cx \equiv b \pmod m \Longleftrightarrow \gcd(c,m)|b$. Show, moreover, that the answer is unique $\bmod{m/\gcd(c,m)}$    My Work  Proof of $(\Rightarrow)$:  Assume that $cx \equiv b \pmod m$ has a solution, call it $x_1$. Let $d = \gcd(c,m)$ Then  \begin{align*} cx_1 \equiv b \pmod m &\Longleftrightarrow m | (cx_1 - b) \\ &\Longleftrightarrow cx_1 = km + b, \quad k \in \Bbb Z \\ &\Longleftrightarrow cx_1 + (-k)m = b \\ \end{align*} As the $\gcd$, $d$ divides all linear combinations of $c$ and $m$, so $d | b$.   Proof of $(\Leftarrow)$:  Assume $d | b$. Then $b = dn$ for some $n \in \Bbb Z$. As the $\gcd$, $d = cs + mt$ for some $s,t$. So  \begin{align*} dn &= csn + mtn \\ b &= csn + mtn \\ csn - b &= (-tn)m \\ csn - b &\equiv 0 \pmod m\\ csn &\equiv b \pmod m \end{align*}  Taking $x = sn$, we have a solution to the linear congruence $cx \equiv b \pmod m$.  My Question  I am not sure how to prove uniqueness from here. Should I say that $cx \equiv b \pmod m$ gives that, for $d = \gcd(c,m)$, $$m | (cx -b ) \Longrightarrow \left({m \over d}\right) \mid \left({cx - b \over d}\right) = {c \over d}x - {b \over d}$$ However, I'm not sure how to move from here to uniqueness. I have that ${c \over d}x = {m\over d}k + {b\over d}$, but this doesn't seem to be much.


Migrated question shows up attributed to nobody on the front page

TL;DR minor bug: a question's showing up on our site that's attributed to nobody at all on the front page. RPG Stack Exchange just now had this happen:   was migrated to our site, belonging to a user (“Light”) who doesn't yet have an account on our site so they show up as anonymous. The question was closed as off topic since we only deal with tabletop games. The question was accordingly locked and the migration was rejected.  Now the question is showing up on our front page with a timestamp but attributed to nobody, not even Community or the anonymous “Light” user. The front page as I see it:  The question page itself:  Possible cause The timestamp on the frontpage appears to correlate exactly to  so presumably this would happen to any migrated question, even if it wasn't closed:  Curiously it has its attribution on the /questions page:


What does $t_0$ mean in constant acceleration equations?

I am using the book Understanding Physics by Mansfield and O'Sullivan. In their derivation of constant acceleration equations, they initially use a time $t_0$ that is not necessarily $0$. They get $v=v(t_0)+a(t-t_0)$ and a similar equation for $x$ (ie one involving $t_0$).  However, I am confused as to what $t_0$ means. According to the authors, $x(t_0)$, $v(t_0)$ and $t_0$ are "starting conditions". They also call $t_0$ the "starting instant".  But what do "starting" and "initial" mean here? As far as I know, we do not need them to be "starting" at all: all that we need is an arbitrary time for which we know $v(t_0)$ and $x(t_0)$. In other words, $t_0$ doesn't need to be initial, it just has to be a random time for which we know $v(t_0)$ and $x(t_0)$, then we can use it to find the constants of integration (by setting $t=t_0$), resulting in the equations above involving $t_0$.  Also, I am still wondering what "starting" in itself actually means: did they start measuring from that time? But measuring what? As I said, we don't need to measure anything: the constant acceleration equations result purely mathematically from the definition of acceleration, ie $a=\frac{dv}{dt}$, and the only thing we need to know to find the constants of integration is the velocity and position for an arbitrary value $t_0$. So what does $t_0$ being an "initial" or "starting" value have anything to do with it? If anything, it only has to be "known".  Edit: It is not the same as the suggested question. That one is whether $t_0$ can be nonzero (the answer is yes), this one on the other hand is about why we call $t_0$ the "initial" or "starting" time, when it is just an arbitrary time for which we happen to know x and v.


Is just 'being interested in the topic' a bad reason to do a PhD?

I've got an offer to do a PhD at a great uni in the UK, in a scientific topic I find really interesting because of some courses I've taken at Master's level.  My dissertation advisor seems to think that being interested in a topic isn't strong enough as a motivation, and that I should be passionate about the topic and have a clear idea of why I want to study it and what it will lead me into.  I wouldn't say I'm passionate about this topic, but I wouldn't say I've studied anything in enough detail to be passionate about anything in particular yet. All I know is that I found this topic interesting and stimulating. People usually get passionate about things when they start doing them at a really high level, which I haven't had a chance to do yet.  Regarding what it would lead me into - I don't know exactly what I want to do in life yet, but research really appeals to me, and so does academia.  Is this reason enough to accept the offer, or should I reject it and wait until I become passionate about a particular area and know exactly what I want to do in life?


Find $f(x)$ where $ f(x)+f\left(\frac{1-x}x\right)=x$

What function satisfies $ f(x)+f\left(\frac{1-x}x\right)=x$ ?


I am clearly missing some with iCloud storage, every few weeks I get an email saying my storage is nearly full and I only have a couple of hundred MB left. So I am always deleting my back up and letting it back up overnight. When I back it up it's only about 3GB. Why is it consistently over the weeks always full? I have no apps being backed up to it either, they're all off. So how do I stop this and what is causing it?  Here is an example of what I mean. It backed up yesterday. I have all the apps off and it wants to back up another 192MB. I haven't sent s load of images in iMessage or anything like this in the last day so I don't know where the data is coming from. I don't take many photos anyway so it's not photos. Unless it has anything to do with Apple Watch? I can't see or find anything about activity app being backed up the cloud, but that's the only thing left I can think of


Why can't we call controllers parameterized methods directly from Visualforce

I am not sure why Visualforce has this limitation that you can't call parameterized method directly from Visulaforce.  Can anybody explain the reason?  Edit  public string getFormatMe(string a) {     // do manipulation here     return a; }   i can't call this function from visualforce directly like getFormatMe('xyz');


Communication & Networks v/s Signal Processing & Optimization - what area to work in?

I am an electrical engineering undergrad with an interest in communication theory, networks, signal processing and optimization. I have PhD offers from two groups - one working in communications & networks and another working in statistical signal processing, compressive sensing & community detection. How do I decide between the two? It is my opinion that currently communication theory and networks have become a mature field with not much scope for rapid growth or fundamental path-breaking research, while the work in the other group is quite more "in vogue" due to machine learning based applications and has the potential to solve more fundamental problems.   A comparison between the two areas with regards to future research and job opportunities would be great.


I know this question has been asked here before, but the answers haven't helped me.  I have a Lenovo Ideapad on which I've installed via UNetbootin 18.04.  Everything else with the install went smoothly, but like others my wifi is not working.  In particular, I've gotten the no wi-fi adapter found message.    Many of the fixes relied on gaining access to the internet via an ethernet connection, but my machine doesn't have a connection for that.  I haven't used Ubuntu in several years so my Linux foo is very rusty. I'm essentially a newbie.   03:00.0 Network controller [0280]:  Realtek Semiconductor Co., Ltd. RTL8821CE 802.11ac PCIe Wireless Network Adapter [10ec:c821]           Subsystem: Lenovo RTL8821CE 802.11ac PCIe Wireless Network Adapter [17aa:co24]   Let me emphasize newbie again.  I don't know how else to post this.  Here's the feedback now that I attempt to run make after updating and upgrading again:  /bin/sh: 1: cc: not found (standard_in) 1: syntax error make ARCH=x86_64 CROSS_COMPILE= -C /lib/modules/4.18.0-15-generic/build M=/home/john/Downloads/rtl8821ce  modules make[1]: Entering directory '/usr/src/linux-headers-4.18.0-15-generic' arch/x86/Makefile:155: CONFIG_X86_X32 enabled but no binutils support ./scripts/gcc-version.sh: line 26: gcc: command not found ./scripts/gcc-version.sh: line 27: gcc: command not found Makefile:970: "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" make[1]: gcc: Command not found make[1]: gcc: Command not found make[1]: gcc: Command not found make[1]: gcc: Command not found /bin/sh: 1: gcc: not found (standard_in) 1: syntax error /home/john/Downloads/rtl8821ce/Makefile:2157: home/john/Downloads/rtl8821ce/hal/phydm/phydm.mk: No such file or directory /home/john/Downloads/rtl8821ce/Makefile:2166: home/john/Downloads/rtl8821ce/rtl8821c.mk: No such file or directory make[2]: *** No rule to make target 'home/john/Downloads/rtl8821ce/rtl8821c.mk'.  Stop. Makefile:1534: recipe for target '_module_/home/john/Downloads/rtl8821ce' failed make[1]: *** [_module_/home/john/Downloads/rtl8821ce] Error 2 make[1]: Leaving directory '/usr/src/linux-headers-4.18.0-15-generic' Makefile:2237: recipe for target 'modules' failed make: *** [modules] Error 2 john@john-Lenovo-ideapad-130S-11IGM:~/Downloads/rtl8821ce$ sudo make install /bin/sh: 1: cc: not found (standard_in) 1: syntax error install -p -m 644 8821ce.ko  /lib/modules/4.18.0-15-generic/kernel/drivers/net/wireless/ install: cannot stat '8821ce.ko': No such file or directory Makefile:2243: recipe for target 'install' failed make: *** [install] Error 1   Ran the commands and got these errors:  E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable) E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it? john@john-Lenovo-ideapad-130S-11IGM:~$ sudo apt-get install libelf-dev E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable) E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?


For me/to me, which is correct or better in these examples?

Prepositions are tricky to figure out. I'd like to know whether or not I can use these two prepositions interchangeably in the following examples.  It's very important for me/to me to study abroad. For me/to me all that matters is how much it will cost. You are the most beautiful girl, at least for me/to me. Living in our house is just unbearable for me/to me.  As an ELL, I have to make sentences in a way like assemblying parts. At times, the contrived sentences may seem to be a little bit unnatural to native speakers, so the examples above are just tokens here. There must be better ways to convey the meaning.


How to find a program which is preventing sleeping?

I am noticing that recently my laptop does not go to sleep/lockout after its configured X minutes of inactivity like it did in the past. I suspect some program (like media player does) is preventing it from going to sleep. I do not have any media player running, so how can I find which program is preventing it from sleeping?  It does go to sleep if I close the lid. But I would also like for it to go to sleep after X minutes of inactivity.  Update: Upgraded to Ubuntu 18.04 with default Gnome and Wayland enabled.


"Every vector space over $\mathbb{Q}$ has a basis" $\Leftrightarrow$ Axiom of choice?

It is known that "every vector space has a basis" $\Leftrightarrow$ Axiom of choice   but do we have the same thing with a vector space over $\mathbb{Q}$?


What video editing software should I use to make screencast videos with external audio?

I want to make screencast videos and record audio externally. What video editing software should I use? This is for an online class in introductory logic that I'm terribly late putting together.  To clarify: I want to record external audio, not internal. I want to highlight lines in a PDF while talking about the material.  I tried recordMyDesktop but it doesn't seem to have an external audio option.


Every uniformly continuous real function has at most linear growth at infinity

Assuming $f:\mathbb R\to\mathbb R $ be an uniform continuous function, how to prove $$\exists a,b\in \mathbb R^+ \quad \text{such that}\quad |f(x)|\le a|x|+b.$$


Is the following series $\sum_{n=0}^\infty \frac{n^3}{n!}$ convergent and if so what is the sum?

I started by converting the following $\sum_{n=0}^\infty \frac{n^3}{n!}$ into  $$\sum_{n=1}^\infty \frac{n(n-1)(n-2)}{n!} + \frac{3n(n-1)}{n!} + \frac{n}{n!}.$$ Did i get it right and where should I go from here ?


Let $A$ be a deformation retract of $X$ and $(j)_*: \pi_1(A,x_0) \to \pi_1(X,x_0)$ be the map induced by the inclusion map $j:A \to X$ (with $x_0 \in A$). I want now proof that for every $x \in \pi_1(X,x_0)$ there exists a $y \in \pi_1(A,x_0)$ s.t. $(j)_*([y])=x$.  Okay since $A$ is a deformation retract there exists a retraction $r: X \to A$ and we have that $r \circ j =id_A$ and $j \circ r \sim id_X$. But how to continue? Can somebody help me?  (We don't know about functoriality yet and so we can't use it.)


Definitive line between minor and substantial edits

OK, this question has been asked over and over, and I am still unsure. I am just trying to find the thin line between a substantial and minor edit.  I find myself making edits for grammar and poor formatting, that I can see some reviewers find minor and others do not.  I have also noticed some users with high rep, or moderators will make the similar edits:     If I have edited your post with an edit summary of “ARGH”... ... or   some variation thereof, then you probably used “it’s” when the correct   word was, in fact, “its”.   Can anyone provide a definitive way to establish whether or not one should proceed to edit? It seems to be more a matter of opinion rather than an objective delineation.


Mojave is eating storage like candy, no matter how much I free up

By my count, I should have 40-50gb free. But starting a few weeks ago, I'd wake up having created no new files, and 5gb would be gone, or 10gb.  Today, it told me that no storage was left. I freed up 5gb by deleting some apps I no longer used... and it has slowly eaten that as I watch the finder window's footer. Down to 546mb at the moment. And there's nothing else left to get rid of.  What the hell is going on? I have a Terminal.app open. I have a Firefox window open (that I'm typing into right now). And a few Sublime tabs.  If I reboot, I'll get maybe 11-12gb of this back... and it will slowly gobble that up over a period of at most a few hours. I don't know what's going.  I don't think this is malware, no files are messed up anywhere, no ransomware horseshit. Where do I start checking? Down to 373mb now.   It has done this in the past, of course, but an hour later whatever it was using that storage for would be freed, and I'd have no incidents for weeks/months afterward. This is the first time that it didn't self-correct.


when I try to load  it goes to the error page.


how to use rsync (using password-less ssh), with sudo just on the local side?

This command works fine for me with password-less ssh:  rsync -aqve ssh ${user}@${remote_host}:/etc/bind /tmp/etc/bind   Since I would like to rsync directly to my own local /etc/bind with root permissions, I tried:  sudo rsync -aqve ssh ${user}@${remote_host}:/etc/bind /etc/bind   But now, I get a password prompt (this is bad).  How do I fix this line to copy directly to my local /etc/bind without a password prompt?


Is it possible to have a global counter that can display its value on the first page? From what I can tell, the only way is to display on the last page after compiling.


strip new line and carriage return in java

I want to strip '\n' and '\r' characters from a text. I use the following regex: "\\n|\\r" and use string.replaceAll().  This works fine and takes off the \n and \r chars from the string, but it also takes off characters from words starting with 'n' and 'r' with a backslash. eg: someword\new  or someword\round  --> someowrd\ew, someword\ound. Is there a better way to construct regex ?   sample code: (I use 4 backslashes before 'n' and 'r')  String line_sep_regex = "(\\\\n|\\\\r)"; String finalString = jsonData.toString().replaceAll(line_sep_regex, StringUtils.EMPTY);   Thank you.


So how would you and extra arguments to a custom bash script like "Nmap -p" I've tried doing research on the subject bit nothing comes up


Were ST:TNG "Force of Nature"-related issues ever addressed in ST:DS9?

If I'm not mistaken, last two seasons of Star Trek The Next Generation were aired in parallel with first two seasons of Star Trek Deep Space Nice, and most of the episodes in both series had their stardates matched. Are there any remarks to issues mentioned in ST:TNG "" (possible destruction of space fabrics by using warp drives) ever addressed or at least mentioned in Star Trek Deep Space Nine?  From what I saw so far (just starting DS9 season IV) there is no such thing.  We have a strict declaration in "Force of Nature", that under no circumstances, except for an extremely dangerous situations, no Federation ship can speed more than warp 5. Yet, we have many clear examples in DS9 in season II and III, where we can see Defiant speeding at warp 8 or so in situations, which barely can be taken as extremely dangerous.  Is there any in-universe explanation for this "glitch"? Or is there something, that I don't follow and there is nothing to explain here, as there is no "glitch"?


Fetching and print results from multiple tables that have same column name. Here's my query: I am trying to fetch the column salt from login and cookie table.  SELECT login.salt      , cookie.salt    FROM login      , cookie   WHERE login.user_id     AND cookie.user_id = :user_id`  login +---------------------------+ | user_id |       salt      | +---------+-----------------+ | 1       |    fromLogin    | | 2       |    fromLogin    |  cookie +---------------------------+ | user_id |       salt      | +---------+-----------------+ | 1       |    fromCookie   | | 2       |    fromCookie   |   The result was:  Array ( [salt] => fromCookie )  How can i print both result out?  PHP  $user_id = 1;  $sql = "SELECT login.salt, cookie.salt FROM login, cookie WHERE login.user_id AND cookie.user_id = :user_id";  $params = array(         'user_id' => $user_id         );  $stmt = $db->justConnect()->prepare($sql); $stmt->execute($params); $result = $stmt->fetch(PDO::FETCH_ASSOC);  print_r($result);


Every time I want to install something with terminal it shows this warning message but it continue to install, what's the problem?     dpkg: warning: files list file for package 'linux-generic' missing; assuming package has no files currently installed


UTF encoding method for persion support in PHP

I inserted some data in to MySQL database tables, it's actually fine inside MySQL database, but shows me the data in browser like this      (???? ???????? ???? ???? ? ????????? ????? ? ???? ?? ???? ? ?????????   ?? ???? ??? ? ???? ????? ???? ?????? ??? ?????? ?? ????? ????? ???????   ?? ???? ??? ? ?? )    but the actual data is     ( تولید سادگی نامفهوم از   صنعت چاپ و با استفاده از طراحان گرافیک است. چاپگرها و متون بلکه   روزنامه و مجله در ستون و سطرآنچنان که لازم است و برای شرایط فعلی   تکنولوژی )   I changed the character set to UTF-8 and collation to utf8_general_ci, but it still doesn't work.


How to remove uninstalled wine app icons from unity dash?

I installed  (for Windows) using wine but turns out LAN Messenger is also available for linux as well. So..   I uninstalled LAN Messenger from wine. I also removed wine. deleted the .wine directory. after that sudo apt-get autoremove and sudo apt-get autoclean. then I installed LAN Messenger using dpkg -i pkgname.deb and it installed successfully.   The problem is that now I get this in dash:   Any Help is highly appreciated.  [NOTE] I am using ubuntu 12.10


How to determine which app is causing vibration?

I have a Moto G6 Play that vibrates like it is getting notifications but it's not. The vibration is inconsistent and seems random so I would like to know if there is a logcat or something I can run to log which app is calling the vibration so that I can shut it off? The same thing happens on my wife's phone, same model, and it does my head in. The device is running Android 9.


How to install GPU drivers in Ubuntu 20.04?

I'm using AMD Radeon x1600/1650 Series GPU in my system, i installed Ubuntu today because i was too bored from Windows. My question is, i downlaoded .run file from the official AMD driver website but i don't know how to install it. Also is there any similar thing to Windows Device Management in ubuntu?


Positive integer solutions to $\frac{x}{y+z}+\frac{y}{x+z}+\frac{z}{x+y}=4$

I was wondering if anyone knew of any positive integer solutions to this Diophantine equation, or had a proof there are none. Integer solutions exist with negative values, such as (11,9,-5) and (4,11,-1), but checking positive integers up through 10,000 yielded nothing and I don't see a way to show there are none.


I am maintaining a VBA Access application and I would like to use a source control.  Is there a way to break up the VBA Application into components and reassemble them when needed?  We are currently using git on azure dev ops for our other projects so if we could implement that as the solution great.  Unforturnately, I can't figure out how to break it down to component pieces.


I like to play tennis on Tuesdays. I like playing tennis on Tuesdays.  Having taken into account the following, would you please throw a light on what is the difference between the sentences above? This question was inspired by a comment left on a similar question I asked , where a user said:  Like playing vs. like to play is the question of gerund vs. infinitive. Both of those are correct, but I don't think there's a general rule.  So, is there some general rule? Or was the comment correct?