Can a Wizard identify the spells in another spellbook without copying them into their own?

If a Wizard finds the spellbook of the evil Wizard they discovered, how does the process of finding out which spells are in the spellbook work? (Assume the evil Wizard didn't simply write the spells' names in common at the top of the pages or create an index.)   Does the Wizard have to spend 2 hours per spell level "deciphering the unique system of notation" to be able to tell that the spell they've been studying is detect magic? Or can they tell at a glance that it's detect magic before spending the 2 hours? Does it require the 50gp per spell level cost just to figure out what the spell is, or do they get to choose whether to spend it after figuring out what spell it is, as part of deciding whether to copy the spell into their spellbook?     From the 5e Basic Rules, Chapter 3, pg. 31 (emphasis mine):     Copying a spell into your spellbook involves reproducing the basic form of the spell, then deciphering the unique system of notation used by the wizard who wrote it. You must practice the spell until you understand the sounds or gestures required, then transcribe it into your spellbook using your own notation.   For each level of the spell, the process takes 2 hours and costs 50 gp. The cost represents material components you expend as you experiment with the spell to master it, as well as the fine inks you need to record it.


can not chown a file from my $user to another $user

I am on slackware64 v14.0 and I have file that belongs to me:  -rwxrwxr-x+   1 nass  shares    137934 Mar  7 00:06 myfile.csv*   I am a member of the "shares" group. The folder that contains myfile looks like this  drwxrwsr-x+  12 nass shares 4096 Mar 12 04:54 winmx/   I now want to give ownership of this file to another user of this pc. The other user is also a member of the shares group. However,   chown otheruser myfile.csv      does not do the trick. I get a  chown: changing ownership of 'myfile.csv': Operation not permitted   I had recently asked a similar  about gid, but this is not the same problem. How can I solve this ?


I have a river network (lines) and a .shp with states (polygon). I would like to split the lines at the state boundaries i.e. split lines by polygon boundaries. Is there a geoprocessing tool to do this in QGIS? I can't merge the lines by the way, since they are meaningfully split into tributaries/main river.


Do contractions (e.g. "don't") and full phrases (e.g. "do not") have the same meaning?

What is the difference between "don't" and "do not" in the English literature as well as spoken English? Are they same?   The same question goes for "wouldn't" and "would not", "couldn't" and "could not".


Let $f$ be a function with domain $A$ and codomain $B$.  It seems that there are two formal definitions of a function:   As a set of ordered pairs: $f=S\subseteq A\times B$ As an ordered triple: $f=(A,B,S)$.     Consider these two functions:   $f:\mathbb \{0\} \rightarrow \mathbb R$ defined by $f(x)=1$ $g:\mathbb \{0\} \rightarrow \mathbb R^+_0$ defined by $g(x)=1$   Under Definition 1, $f=g=\{(0,1)\}$.  But under Definition 2, $f \neq g$ because $f=(\{0\},\mathbb R,\{(0,1)\})$, while $g=(\{0\},\mathbb R^+_0,\{(0,1)\})$.  So, which is the "correct" definition that we should use?


It's possible to add a spell checker to the search function?  Something like the Google one...  (for instance if I write blacd hole in this site I found nothing, while in Google he understand that I want to search for the word black hole).  It's not compelling, but it can be really useful especially for non-english native speakers.


Is there an online course in Mathematical Methods for Physics, Covering Matrices and Vector Analysis?

I am taking a course in Mathematical Methods for physicsPhysics (Junior Level).   We are working from   > Mathematical Methods for physicists, George B.Arfken .    I just need online resources covering ( Matrices, Determinants, Vector Analysis, Tensors and differential forms and Vector spaces...etc) to study and understand from.


The new profile shouldn't mistakenly imply that you can earn the Informed badge on a meta site

I just joined Sports, and I decided to take a look on Sports Meta. I clicked on my profile there. This is part of what I saw:     Yet the profile shouldn't indicate that it is, in theory. . .  This seems to be a bug.


I have some problems with the bibliography of my thesis and Jabref.  I don't understand why some URL or DOI go out the borders... Can you help me?    \documentclass{article} \usepackage[backend=bibtex,style=phys,biblabel=brackets,natbib=true,sorting=none,url=true,hyperref=auto]{biblatex}  \addbibresource{tesi.bib}  \usepackage[autostyle=true]{csquotes}  \begin{document}  \setcounter{biburlnumpenalty}{8000}  \printbibliography[heading=bibintoc]  \end{document}


recursively delete subdirectories and files

I have the following files and directories configuration:  -Parent_dir     |-delme_dir     |-delme_file     |-aFile     |-sub_dir         |-delme_dir         |-delme_file         |-aFile         |-sub_dir             |-delme_dir             |-delme_file             |-aFile     |-sub_dir2         |-delme_dir         |-delme_file         |-aFile   Is there a command that I can use from the Parent_dir to recursively remove all the delme_dir directories and the delme_file files ?


Why does adding red light with blue light give purple light?

Our eyes contain 3 photoreceptor cells (cones) to perceive three wavelength ranges of light. Here is a visual representation of the wavelengths by these receptors (S, M and L).    So if we have light of 440 nm, it results in the color blue. If we have light of 540 nm, it results in the color green. If we see light of 650 nm, it results in the color red.  I think I understand our ability of the brain to mix the results of the signals of these receptors, producing colors like yellow. However, what I do not understand is how the color spectrum is displayed like this:    Given that spectrum, I would suggest that the color 'blue' is actually a mix between the receptors S and M. And the pure result of activating the S-receptor would result in the color 'purple' (I would describe the color in the left of the image as purple, right). Therefore, the receptor colors should instead be RGP (red, green, purple) instead of RGB (red, green, blue).  However, there is one problem with this which I cannot explain. How come that mixing red light with blue light also results in purple light? How is it possible that purple light can be achieved through mixing (additively) blue and red light, just as going to the shortest wavelength boundary of what we can see (from blue to ultraviolet via purple)?  So the actual problem here is:   Purple is the color at the very shortest wavelength we can see. Purple is an additive mix between what we see as red light and blue light.   That just doesn't make any sense. I don't see how our brain can possibly perceive this as being the same color. Shouldn't both purple colors actually be different colors (thus we would have a new different color for that)?  UPDATE: Pure activation of the S-cone (blue) may actually give violet instead of blue. That means that the color blue contains also a bit activation from the M- and L-cones (green and red). So then the "blue-est blue" is actually violet, not blue. This confusion originates from the RGB-system (and other sources) that assume blue as being a primary color, whereas violet would perhaps be more accurate! Further details can be found in the accepted answer.  The  may further help to understand what purple/magenta/violet really is.


Why doesn't LaTeX allow me to import my .eps file when I compile it?

Everything works perfectly except until the error below. I'm slightly new at LaTeX and perhaps I'm missing a package, but I already have the graphicx package. Any help will be greatly appreciated!  ! LaTeX Error: Unknown graphics extension: .eps.  See the LaTeX manual or LaTeX Companion for explanation. Type  H <return>  for immediate help.  ...                                                l.24 \includegraphics[width=2.6in]{02_1.eps}  ?


OAuth 2.0 User-Agent flow, why is it okay to keep the refresh token when it is considered unable to protect the secret

When I read the oauth 2.0 flows, the user-agent flow states itself to be used when the application is unable to protect the secret.   But in the user-agent flow it is okay to have a refresh token which can last very long - even indefinitely based on settings. How come it is okay for the user-agent to keep that refresh token?   And also, what is the major difference between a refresh token and an authentication code? I know this might sound stupid, but to me, it seems both of them can be used to apply for access token?


$R[X]$ noetherian with $R$ non noetherian

Let $R$ be a ring. If $R[X]$ is noetherian, is R necessarily noetherian ?  I think that the answer is no, but could you show me the easiest example to understand ?


Intercept a process during execution time

I am developing an application must intercept a process and prevent it from executing fully until a users credentials are verified. I have no idea where to go or to begin researching.  I know it is possible as Kaspersky AntiVirus has something similar - when you launch application A, it checks its white list for application A and if it is not found, it halts execution and prompts the user with a question - only when the user clicks Allow, execution resumes.


Select lines from text file which have ids listed in another file

I use a lot of grep awk sort in my unix shell to work with medium-sized (around 10M-100M lines) tab-separated column text files. In this respect unix shell is my spreadsheet.  But I have one huge problem, that is selecting records given a list of IDs.  Having table.csv file with format id\tfoo\tbar... and ids.csv file with list of ids, only select records from table.csv with id present in ids.csv.  kind of  but with shell, not perl.  grep -F obviously produces false positives if ids are variable width. join is an utility I could never figure out. First of all, it requires alphabetic sorting (my files are usually numerically sorted), but even then I can't get it to work without complaining about incorrect order and skipping some records. So I don't like it. grep -f against file with ^id\t-s is very slow when number of ids is large. awk is cumbersome.  Are there any good solutions for this? Any specific tools for tab-separated files? Extra functionality will be most welcome too.  UPD: Corrected sort -> join


python if statement too long and ugly, is there a way to shorten it

i have this long and ugly else if statement in python, is there a way to condense it into a shorter block of code maybe on one line or two if possible because it seems like there would be a way of shortening a piece of code like this  if p == "A": y = 10         elif p == "B": y = 11 elif p == "C": y = 12 elif p == "D": y = 13 elif p == "E": y = 14 elif p == "F": y = 15


Original object getting modified, even though I'm using the spread operator

I'm working on a React app where you have a have a form where you can add a new employee and X number of dependents.  In the form, I set a default state like this:  class NewEmployee extends Component {   state = {     employees: [],     costEstimates: { ...emptyCosts },     relationshipOptions: [],     newEmployee: { ...emptyEmployee }   };   That emptyEmployee is coming from a const in a separate file, and it looks like this:  export const emptyEmployee = { firstName: '', lastName: '', dependents: [] };   I do this purely to just try and keep the initial state looking tidy in the code.  My problem is that the dependents array in emptyEmployee is getting modified, and I don't understand how. This is the function getting called when the user clicks to add a new dependent:    handleNewDependent = () => {     const newEmployee = { ...this.state.newEmployee };     // blank dependent for now     const dependent = {       firstName: '',       lastName: ''     };      newEmployee.dependents.push(dependent);      this.setState({ newEmployee });   };   I've pinpointed that this is when the dependents array of my emptyEmployee object gets modified. I don't understand how, since I use the spread operator to make a copy.


This is part of a bash script code I wish to use multi-threading  for DATABASE in $DATABASES ; do     echo Converting $DATABASE     # Check if the table is MyISAM (we don't want to convert InnoDB tables over and over again)     TABLES=$(echo "SELECT TABLE_NAME FROM information_schema.TABLES where TABLE_SCHEMA = '$DATABASE' and ENGINE = 'MyISAM'" | $MYSQL_COMMAND)     for TABLE in $TABLES ; do         echo Converting MyISAM $TABLE to InnoDB         echo "ALTER TABLE $TABLE ENGINE = INNODB" | $MYSQL_COMMAND $DATABASE     done     if [ "x$TABLES" = "x" ] ; then         echo No MyISAM tables found in $DATABASE database     fi     echo done   Is it possible for FOR to use multi-threading?  I was thinking about rewriting the script and doing it with xargs -P3 -n1 -I{} and so on, but it looks dirty to me.


SF short story about a "Groundhog Day" kind of party that repeats itself forever

This is probably a tough one. It's a short story I read in an SF anthology (of American stories translated in French). It must have been written in the 60s or 70s.  It's about a sort of "time loop", where people are "stuck" in a one night moment, a wild party that repeats itself forever come each new day - which is in fact not a new day, but the repetition of that one same night. Everybody can get wild and crazy and careless, because there are no consequences, everything is back to where it was the next day.  As far as I remember, there isn't much of a big twist, just the main character realizing finally what's going on and that he's also stuck in that forever repeating moment. And that he can have a blast too. But the writing was very vivid, that's why I'm trying to track it down.  Sounds familiar to anybody ? Thanks :)  EDIT : apparently a similar (and much more accurate...) question was already asked, and answered, about this story :  But I feel my entry would still be useful for somebody searching through the "time loop" and "forever party" angles (which is what I remembered), and not "duplicators".


I sent a tweet to someone. It wasn't part of an ongoing conversation. It was just something I sent to them. I asked someone in a forum I was in if they could read the tweet I had sent. This person wasn't the recipient, yet they were able to read my tweet to the other person.   I've NEVER been able to read the tweets sent to someone. If I go into someone's timeline, the only thing I see are tweets that they've sent, as well as replies, etc. But I'm not able to see tweets sent to them. Is there some setting that I"m missing? This is very frustrating.


True or false: infinite sequence in a compact topological group is dense.

This is from an exercise in Bredon's Topology and Geometry:  Let $G$ be a compact topological group (assumed to be Hausdorff). Let $g\in G$ and define $A=\{g^n:n=0,1,2...\}$. Then show that the closure $\bar{A}$ is a topological subgroup.  Note if the assumption of compactness is dropped, then the statement is false. A counterexample is $\mathbb{N}\subset \mathbb{R}$ as additive sets. Note: if we add the assumption of $G$ being 1st countable, this question is easy to answer. So, if the set $A$ is finite, then it is a cyclic group and it is already closed. In the infinite case, I can only think of the example of an infinite subgroup of the circle group, which is dense in compact group. I am not sure how to proceed with the proof of this general fact. Any hint will be appreciated.


I searched it a while and found some articles regarding Xperia Mini X10 also on XDA but I couldn't understand them easily. So I want help from you geeks who can give me the lighted way with simple steps to root my phone.    I want a step by step guide about to root this model. I'm a not much familiar with this technology so please guide me through some detailed answer.


I was trying to execute a jquery code in jsfiddle. My jquery code is given below  $(function() {     var scntDiv = $('#p_scents');     var i = $('#p_scents p').size() + 1;      $('#addScnt').on('click', function() {             $('
<input type="text" id="p_scnt" size="20" name="p_scnt_' + i +'" value="" placeholder="Input Value" /> Remove
').appendTo(scntDiv);             i++;             return false;     });      $('#remScnt').on('click', function() {          alert("sfdrijg");             if( i > 2 ) {                     $(this).parents('p').remove();                     i--;             }             return false;     }); });   My HTML code is given below.
Add Another Input Box

     <input type="text" id="p_scnt" size="20" name="p_scnt" value="" placeholder="Input Value" />

   My Page Looks like this    The click of the "Add Another Input Box" always works whereas the "Remove" does not respond at all.


Converting a decimal number with non-repeating and repeating digits to an improper fraction

What are the steps to convert $3.2\overline{901234567}$ to an improper fraction?


The motto for Hogwarts is "Draco Dormiens Nunquam Titillandus", or, "Never tickle a sleeping dragon".  This seems like quite obvious advice and rather silly as a school motto.  Is it essentially an inside joke that J. K. Rowling made up for those that would actually translate it?  Or does it have any particular meaning beyond the literal?  Is it possible she used it as a hint or tip-off that Draco might be more dangerous than we thought (and maybe later changed her mind on that?)  Has she ever indicated there to be more than just the literal meaning for this phrase?


A uniform rod of length L and mass M is attached to a wall by a hinge at its base. Its initial position is horizontal. Why is the initial potential energy of the rod   $U = Mg\frac{L}{2}$,  that is, we use its center of mass to calculate U. Why can't we use the other end of the rod to calculate the energy?


An algebraic structure with non-unique inverses?

It is known that in groups, rings, and fields, the inverse of any element under the operations of the structure, provided it exists, is unique.  Can one define a set of elements, along with an operation, such that the inverse is NOT unique?  What properties would such a structure have?


Multi lines within ul element breaking my regex pattern

Live example:   Source markup:  <xf:macro name="breadcrumbs" arg-breadcrumbs="!" arg-navTree="!" arg-selectedNavEntry="{{ null }}" arg-variant="">     <xf:if contentcheck="true">         <ul class="p-breadcrumbs {{ $variant ? 'p-breadcrumbs--' . $variant : '' }}"             itemscope itemtype="https://schema.org/BreadcrumbList">         <xf:contentcheck>             <xf:set var="$position" value="{{ 0 }}" />              <xf:set var="$rootBreadcrumb" value="{$navTree.{$xf.options.rootBreadcrumb}}" />             <xf:if is="$rootBreadcrumb AND $rootBreadcrumb.href != $xf.uri">                 <xf:set var="$position" value="{{ $position + 1 }}" />                 <xf:macro name="crumb"                     arg-position="{$position}"                     arg-href="{$rootBreadcrumb.href}"                     arg-value="{$rootBreadcrumb.title}" />             </xf:if>              <xf:if is="$selectedNavEntry && $selectedNavEntry.href && $selectedNavEntry.href != $xf.uri && $selectedNavEntry.href != $rootBreadcrumb.href">                 <xf:set var="$position" value="{{ $position + 1 }}" />                 <xf:macro name="crumb"                     arg-position="{$position}"                     arg-href="{$selectedNavEntry.href}"                     arg-value="{$selectedNavEntry.title}" />             </xf:if>             <xf:foreach loop="$breadcrumbs" value="$breadcrumb" if="$breadcrumb.href != $xf.uri">                 <xf:set var="$position" value="{{ $position + 1 }}" />                 <xf:macro name="crumb"                     arg-position="{$position}"                     arg-href="{$breadcrumb.href}"                     arg-value="{$breadcrumb.value}" />             </xf:foreach>          </xf:contentcheck>         </ul>     </xf:if> </xf:macro>   I'm trying to grab the ul.p-breadcrumbs element via regex. I can grab the ul and everything after ok using:  <p.*class.p-breadcrumbs(.*[\s]*)*   And I can select the closing tag with  <\/ul>   However putting them together doesn't work at all:  <ul.*class=.p-breadcrumbs(.*[\s]*)*<\/ul>   I followed this answer:   But it doesn't work with multiline content. If you line break that example and enter more content it breaks the solution. Appreciate any pointers as I'm pulling hair out trying to solve the last bit!


Adding (partial) support for Japanese in biblatex-apa

For such a support we face two kinds of main problems. Guidelines As far as I'm aware APA doesn't actually provide any official instructions on L10N. So one could argue what would even mean to support Japanese within APA style. Technical Problems Most of packages, even those which has some kind of support for L10N are centered around English or Indo-European languages with Latin scripts at best. So it makes it fairly hard to add support for languages such as Japanese (which for example tends to use postpositions rather then prepositions being an SOV language) without actually writing yet another package which will end up incompatible with a lot of other packages even if we consider the time and effort worth it. Possible Solutions A good solution but a huge undertaking might be redesigning the L10N process of biblatex, providing more high-level flexibility to support different languages. But I see that highly unlikely, so in the meantime some non-hackish methods to change styles per bib entry (by lnagid for example) and the ability to add manual entries would save a lot of headache. A specific case An obvious first step for a support would be copying some languages' .lbx and -apa.lbx files and translating some strings. Which would lead us to this ( is a sample tex file):  There are quite a few issues here, firstly, 'から' is a postposition unlike 'from' and should come after the URL (which might sound weird if considering the guideline). Secondly the date is completey wrong, it needs to be reordered and also needs suffixes for all 3 entries like '２０１９年９月11日'. Other problems might include not using Japanese parenthesis (and well almost all punctuation marks) which can lead to wrong spacing at points, dots being added after the name which isn't really usual in Japanese (I don't have much information about their typical stylings though). I've managed to fix the first problem after looking into some questions and skimming thorough biblatex-apa's sources by adding the following: \AtEveryBibitem{%     \iffieldequalstr{langid}{japanese}     {\renewbibmacro*{url+urldate}{%             \ifthenelse{\iffieldundef{url}\OR\NOT\iffieldundef{doi}}             {}             {\iffieldundef{urlyear}                 {}                 {\printtext{\bibstring{retrieved}}%                     \addspace                     \printurldate                     \setunit{\addcomma\addspace}}                 \iffieldundef{url}{}{\printfield{url}\bibstring{from}\adddot %                 \renewcommand*{\finentrypunct}{\relax}}}}} % if true      {\renewbibmacro*{url+urldate}{%             \ifthenelse{\iffieldundef{url}\OR\NOT\iffieldundef{doi}}             {}             {\iffieldundef{urlyear}                 {}                 {\printtext{\bibstring{retrieved}}%                     \addspace                     \printurldate                     \setunit{\urldatecomma}%                     \bibstring{from}%                     \setunit{\addspace}}%                 \iffieldundef{url}{}{\printfield{url}\renewcommand*{\finentrypunct}{\relax}}}}} % if false }  Which would give us (Do I need to redefine it on each entry for non-jp entries?):  But the date (the biggest issue) and the rest still remain, and all these are only for considering a single use case.


I have been working on this small problem for hours and cant seem to find problem, bassically it is not recognising a word when i compare user entered word to a word in the array list. Here is code:   birdToRemove = JOptionPane.showInputDialog("Type bird to remove, or cancel  to continue");     while(increment <= amountBirds)     {          if(birdToRemove == birdArray[increment])         {             found = true;             birdArray[increment] = null;              JOptionPane.showMessageDialog(null, "Deleted");             deleteEntry();         }         if(birdArray[increment] != birdToRemove)         {             increment = increment + 1;         }     }      if(found == false)     {         JOptionPane.showMessageDialog(null, "Error, bird not found", "Error", JOptionPane.ERROR_MESSAGE);     }   Everytime it will say Error bird not found Kind regards Jordan


I'd like to create a Categorized style in QGIS, classify with it data in a shapefile and then save the shapefile with the new categorized style. Is it possible?


Finding the limit of $\left(\dfrac{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}}{3}\right)^n$

I'm trying to solve this limit, for which I already know the solution thanks to Wolfram|Alpha to be $\sqrt[3]{abc}$:  $$\lim_{n\rightarrow\infty}\left(\frac{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}}{3}\right)^n:\forall a,b,c\in\mathbb{R}^+$$  As this limit is an indeterminate form of the type $1^\infty$, I've been trying to approach it by doing:  $$\lim_{n\rightarrow\infty}\left(\frac{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}}{3}\right)^n=\lim_{n\rightarrow\infty}\left(1+\frac{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}-3}{3}\right)^n=\lim_{n\rightarrow\infty}\left(1+\frac{1}{\frac{3}{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}-3}}\right)^n=\lim_{n\rightarrow\infty}\left(1+\frac{1}{\frac{3}{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}-3}}\right)^{\frac{3}{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}-3}\cdot\frac{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}-3}{3}\cdot n}=e^{\lim_{n\rightarrow\infty}\frac{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}-3}{3}\cdot n}$$  But now when I approach that top limit this is what I get:  $$\lim_{n\rightarrow\infty}\frac{a^\frac{1}{n}+b^\frac{1}{n}+c^\frac{1}{n}-3}{3}\cdot n=\lim_{n\rightarrow\infty}\frac{n\cdot a^{\frac{1}{n}}}{3}+\frac{n\cdot b^{\frac{1}{n}}}{3}+\frac{n\cdot c^{\frac{1}{n}}}{3}-n=\lim_{n\rightarrow\infty}\frac{n\cdot a^0}{3}+\frac{n\cdot b^0}{3}+\frac{n\cdot c^0}{3}-n=\lim_{n\rightarrow\infty}\frac{n}{3}+\frac{n}{3}+\frac{n}{3}-n=0$$  And hence the final limit should be $e^0=1$ which is clearly wrong but I honestly don't know what I did wrong, so what do you suggest me to solve this limit?


No injection between the power set of a set A and the set A.

For finite sets it's easy to prove it because the cardinal of the power set it's bigger than that of the set so there won't be enough elements in the codomain for the function to be injective. What is the proof for infinte sets though?  Thanks in advance.


I just started my Masters in computer science, and I started working on a research project with one of my professors last term as a part of a class project for his class. In relation to that project, he has asked me to help him review a paper that is being reviewed to determine whether it will be accepted or rejected for a conference. I have agreed to review the paper. However, I have never written this type of paper review before. What are the steps you go through in reviewing a paper to determine if it should be accepted or rejected?


I'm running a script that uses a module that prints a lot of things on screen and I'm running out of RAM. I can't make the module not to write anything for now. The Python Shell stores absolutely everything and I want to clear it. On similar questions the only answer I could find was to write os.system('cls') (on Windows), but it doesn't delete anything. Is there a way to clear the Python Shell or to limit its size? Thanks      Edit. Well, this question was marked as duplicate and I am asked to clarify why it isn't. I state that os.system('cls') doesn't work, while the answer to the question I supoosedly duplicate is to write os.system('cls').


I am arguing with friends about this question.  According to what I learned in school, there are some adjectives that cannot be used in the progressive form.  I think this one is ungrammatical because angry describes an emotion, which is a temporary state on its own. Therefore, it is redundant to use it in the progressive form.  Am I correct?


Enviroment: Plesk v12, latest Windows Server 2012 SmarterMail  My web hosting provider told me that someone hacked into my server a couple of weeks ago and was hitting various mail servers (Gmail, Yahoo, etc).  I worked with the company to cure the problem, basically: * Change all passwords * Update server and all software to latest version * Turn on Windows firewall, was somehow disabled  Doing these tasks and waiting a couple of weeks finally took me off all the blacklists and restored my MXToolbox rating.  I found out today that Microsoft blacklisted my IP (not reported by the free version of MxToolbox). They said that a few days ago (8/28 and 8/29) that there was still Namespace Mining going on, but offered no information on how they know, how to prevent, or anything else that I asked. They wrote me back to my questions a few minutes ago that upon further investigation that they will lift the block.  Questions:   How does Namespace mining occur? Is that the result of a hacker finding out or hijacking an email account? Aside from inspecting the logs, how can I determine if there is Namespace mining occuring? How do I prevent Namespace mining beyond what I did? Would that be by installing a professional security software (e.g. third party Antivirus / Firewall / Email security software)?   I resolved the current problem, but I would like to know how to find out if I have the problem. In this case, I tried to send an email to a Microsoft account of mine and received a failure report. There should be a better way to go about a check then accidentally discovering the problem.


CORS problem when trying to call WMS getFeatureInfoUrl using OpenLayers

I'm using the newest stable version of OpenLayers which is 6.3.1.  I have a problem when trying to call http request on an url genereted by the wmsSource.getFeatureInfoUrl function. It returns me an URL and when I execute this url directly on the newly opened tab on my browser I get the detailed result about the cliecked point on a map. But when my Angular app is calling this url I have a CORS error:  Access to XMLHttpRequest at 'http://q1.geopartner.ad/cgi-bin/qgis_mapserv.fcgi?map=/qgisdata/projekty/Q_postD.qgz&SERVICE=WMS&VERSION=1.3.0&REQUEST=GetFeatureInfo&FORMAT=image%2Fpng&TRANSPARENT=true&QUERY_LAYERS=dzialki&LAYERS=dzialki&INFO_FORMAT=text%2Fhtml&I=126&J=31&WIDTH=256&HEIGHT=256&CRS=EPSG%3A3857&STYLES=&BBOX=2035059.4410645328%2C6966165.009797823%2C2074195.1995465432%2C7005300.768279833' from origin 'http://localhost:4200' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.   My url won't be available for you cause it's only available behind the VPN connection. Here is my code:  const wmsSource = new TileWMS({   url: 'http://q1.geopartner.ad/cgi-bin/qgis_mapserv.fcgi?map=/qgisdata/projekty/Q_postD.qgz',   params: { LAYERS: 'dzialki' } });  const wmsLayer = new TileLayer({   source: wmsSource });  const view = new View({   center: [ 2071206.0066185605, 6997895.536649533 ],   zoom: 10, });  const map = new Map({   layers: [wmsLayer],   target: 'map',   view });  map.on('singleclick', function(evt) {   document.getElementById('info').innerHTML = '';    const viewResolution = view.getResolution();   const viewProjection = view.getProjection();    console.log('viewProjection', viewProjection);    const url = wmsSource.getFeatureInfoUrl(     evt.coordinate,     viewResolution,     viewProjection,     { INFO_FORMAT: 'text/html' });    if (url) {     console.log('url', url);      const Http = new XMLHttpRequest();     Http.open('GET', url);     Http.send();      Http.onreadystatechange = (e) => {       console.log(Http.responseText);     };   } });   The map is loading correctly, I can zoom in/out etc. And when I click on the map I have the problem which I described. How can I fix it?


Is it better to have one large memory card or several smaller ones?

I don't think anyone can give a definitive answer, but what are the factors I should consider?  What are the pros and cons?    I'm thinking: What are the costs? the risks? How is usability affected? Anything else?    Can you give any concrete examples or experiences you have had which incline you one way or the other?    Any thoughts gratefully received.


Let $f:\ \mathbb{R} \rightarrow \mathbb{R}:\ x \mapsto f(x)$ be a function that is derivable on $\mathbb{R}_0$. Suppose that we know that $\lim_{x \rightarrow 0}f'(x)$ exists and is finite. Can we conclude that $f$ is derivable in $0$?  What I'm trying to prove is that the following limit exists: $$\lim_{x \rightarrow 0}\frac{f(x)-f(0)}{x}$$ I have feeling that we're going to require uniform continuity somewhere. I started out by writing out the limit in full:  $$\lim_{a \rightarrow 0}f'(a) = \lim_{a \rightarrow 0}\lim_{x \rightarrow a}\frac{f(x)-f(a)}{x-a}$$  Now, can I just say the following or are there preconditions? $$\lim_{a \rightarrow 0}\lim_{x \rightarrow a}\frac{f(x)-f(a)}{x-a} = \lim_{x \rightarrow 0}\frac{f(x)-f(0)}{x}$$


Is it fair to buy a return ticket I know I will never use just because it's cheaper?

I am planning a trip to Asia and then back to Rio. The thing is that I am traveling on flexible dates, so I am thinking of buying a one way ticket to Hong Kong, and I was planning to do the same when I want to come back.  But what I noticed is that, for example, a one way ticket from Melbourne to Rio costs no less than $2700 dollars for the month of May.  When I do a search for a round-trip from Melbourne to Rio and back, I can find flights for $2200.  I know I will not be using that return to Melbourne, but I'd still prefer to save those $500.   Can there be any issue with buying a round-trip with a return that I will never use?


Why queuable apex accepts sobjects where as future methods doesn't?

I was going through asynchronous apex and reading it made me confused at one point. In future methods, we cannot pass sojects for reasons future methods being executed at a later point of time, by the time it is executed the sboject data could be stale. But, at the same time, the more advanced queuable apex accepts sobjects. Why is it so? The same reason is applicable for queuable apex also right? kindly clarify.


I just made pushed a commit, then realized I needed to change the commit message.   So on my local repo I did:  git commit --amend -m "New commit message"   But when I then tried to push this, I got loads of error messages saying  Updates were rejected because the tip of your current branch is behind hint: its remote counterpart. Merge the remote changes (e.g. 'git pull') and try again   Was this the wrong way to amend my message? In the end I ended up having to reset all my repos and then do the commits again with a fresh message.  So my question is, what is the proper way to amend the commit message of something that has already been pushed?


I've been wondering why the ubuntu's version of chromium is still on 25 -- from lucid up until  raring -- while the current stable version is 28. The only reason I use chromium is to use the web apps integration.  PS : I have tried to use the web apps integration on another version of chromium -- not google chrome -- which is 28 then it seems that some features I use was lost while using other version than 25.  EDIT: Sorry I forgot to tell you I use the 13.04 version and also the development branch 13.10. My question was : Why does ubuntu doesn't update the package in the repository to the current stable version?


How do you calculate the probability density function of the maximum of a sample of IID uniform random variables?

Given the random variable  $$Y = \max(X_1, X_2, \ldots, X_n)$$  where $X_i$ are IID uniform variables, how do I calculate the PDF of $Y$?


How many ways there are to arrange 40 people to play exactly one match each?

A tennis club has 40 members. They host a tournament playing single   (one verses one) matches. Every member of the club plays one match   with another member of he club, so twenty matches are held. (a) In how   many ways can this be arranged?   I was a little confused by the wording of this question in regards to the teams being 'arranged' but I was wondering if it is as simple as the number of ways to choose 20 different match setups, i.e number of ways to choose two different people out of 40. So tried:  C(40,2) and wasn't sure if I needed to multiply by the number of people: so C(40, 2) * 40. I also thought this could be a circular arrangement problem but wasn't sure.. Am I on the right track or way off here?


I am doing a Kruskal-wallis test and am wondering which post-hoc analysis is the most suitable for this? Been reading around and saw people recommend Dunn test. I am just wondering if there is any specific reason to not choosing something like Wilcoxon as they both non-parametric?


"There’s two different but related frameworks..."   Above is a quote from a Kindle book. How come it is "is" instead of "are"? Isn't it grammarly wrong?


How do I prove: $\cos (\theta + 90^\circ) \equiv - \sin \theta $

How do I go about proving this? I know one method is:  $\eqalign{    \cos (90^\circ + \theta ) &\equiv \cos90^\circ \cos\theta  - \sin90^\circ \sin\theta   \cr    &  \equiv (0)(\cos\theta ) - (1)(\sin \theta )  \cr    &  \equiv  - \sin \theta  \cr} $  I'd appreciate others, particularly ones that will allow me to visualize this identity on the unit circle.  Thanks alot.


java: Problem on second if condition , NullPointerException

i'm trying to make a printDetails(); method but i keep getting an error "NullPointerException"  the method is on class Customer on the second if condition i tried replacing the condition statements, and tried declaring the calculateTotalPrice(); as a variable, and tried else if but all didn't work      CODE   public class Main {  public static void main(String[] args) {     Studio studio1 = new Studio(1,2799,0.1);     Customer c1 = new Customer("02","Naif", studio1);      Suite suite1 = new Suite(1, 3200, "Free breakfast");     Customer c2 = new Customer("02", "Faisal", suite1);      c1.printDetails();     c2.printDetails();   the customer class       public void printDetails() {     if (studio.isEmpty()){         System.out.println("Customer '" + name + "' ID: " + id + ", Reserved a studio with a total of '" + studio.calculateTotalPrice()+ "'");     }      if (suite.isEmpty()){         System.out.println("Customer '" + name + "' ID: " + id + ", Reserved a suite with a VIP service of '" + suite.VIPServices+ "'");     } }   the isEmpty() method:  public boolean isEmpty(){         return true;     }   EDIT:   i solved it using a flag  in customer class i added public int flag  and on first const  flag =1  second const  flag =2


This sound very basic to some but I am confused here.  I want to install TeXmaker on my PC (Windows Vista). I downloaded the software from   Now when I try to compile my small example I am getting this :    My question is: why am I getting this? Secondly what is MiKTex?  Can someone please summarize the steps that one needs to do for installing TeXmaker on a Windows machine for the first time?


How can I easily clone my entire system?

I am running an Ubuntu 14.04 LTS and I experienced some issues with my hard drive. I bought a new HDD of the same size (1TB), and I intend to move all my data (softs, work, pics, etc.) on the new HDD.  What is the easiest way to do that?


I can't seem to solve this Table align error. Please help

\documentclass[11pt]{article}  \usepackage[utf8]{inputenc} \usepackage{listings} \usepackage{amsmath} \usepackage{amssymb}  \begin {document}  \begin{tabular}{|c|c|c|} \hline Characteristic & DSPWM & DSVPWM \\ \hline Boosting & - & - \\ \hline DC Utilization & Less & 15% More \\ \hline THD & More & Less \\ \hline pf & Poor & Greater \\ \hline Switching Loss & More & Less \\ \hline \end{tabular}   \end{document}`


How do I improve this? How can I put semicolon?

Being taught and raised in a society; where art and design is an awful career option, I still manage myself pursuing my inner desire anyway.


How to extract quotations from text using NLTK

I have a project wherein I need to extract quotations from a huge set of articles . Here ,  by quotations I mean things said by people , for eg: Alen said " text to be extracted ." I'm using NLTK for my other NLP related tasks so any solution using NLTK or any kind of Python library would be quite useful.  Thanks


By accident I came across this simple math equation which PowerShell gets wrong.   PS 99.804-99.258 0.546000000000006  PS 10.804-10.258 0.546000000000001   This made me curious and I tried some different calculators and most Calculator gets it right and return  0.546   And:  PS 1.804-1.258 0.546   is correct too. But I found other calculators that also returned wrong results:  0.54600000000001 0.545999999999999999 0.5460000000000065   Why does this happen and how can I get the correct result in PowerShell?


I'm having trouble showing that $\text{Gal}(\mathbb{Q}(\zeta_n)/\mathbb{Q})$ is Abelian. First I want to be able to show that $\mathbb{Q}(\zeta_n)/\mathbb{Q}$ is Galois, but I'm also not sure how to do this. Any help is appreciated!


How can I disable my laptop's built-in keyboard in Windows 7?

I have a HP Compaq Presario C700 laptop with Windows 7 installed on it.  My laptop's keyboard is not working properly; some keys never work and some keys will keep on pressing. I've formatted the OS but it didn't solve my problem.  I bought an external USB keyboard and it works well. As some keys in the built-in keyboard activate themselves, I still couldn't work effectively.  After searching Google I tried the following steps to disable the built-in keyboard:   Disabled keyboard drivers: This didn't work because when the system reboots, the driver gets installed again automatically. Installed irrelevant driver for keyboard: This failed - I couldn't install the driver. After rebooting it installed the correct driver automatically.   Can anyone help explain how I can temporarily uninstall my built-in keyboard? I don't want to remove it manually (removing the hardware cable).


java.lang.NullPointerException - in AddCell method

Executing the Code Below : Null Point Exception is Thrown -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------   package eCommerceLive;  import java.io.File; import jxl.Workbook; import jxl.write.WritableSheet; import jxl.write.WritableWorkbook; import jxl.write.Label; import jxl.write.WriteException;   public class dataSheet {  static Workbook wbook; static WritableWorkbook wwbCopy; static String ExecutedTestCasesSheet; static WritableSheet shSheet;  public void readExcel() { try{ wbook = Workbook.getWorkbook(new File("D:\\Automation\\testSampleData.xls")); wwbCopy = Workbook.createWorkbook(new File("D:\\Automation\\testSampleDataCopy.xls"), wbook); shSheet = wwbCopy.getSheet(0); } catch(Exception e) {     e.printStackTrace(); } }  public void setValueIntoCell(String strSheetName,int iColumnNumber, int iRowNumber,String strData) throws WriteException {     WritableSheet wshTemp = wwbCopy.getSheet(strSheetName);     Label labTemp = new Label(iColumnNumber, iRowNumber, strData);      try {         wshTemp.addCell(labTemp);          }          catch (Exception e)          {              System.out.println("Hello");             e.printStackTrace();         } }  public void closeFile() {     try {         // Closing the writable work book         wwbCopy.write();         wwbCopy.close();          // Closing the original work book         wbook.close();     } catch (Exception e)      {         e.printStackTrace();     } }  public static void main(String[] args) throws WriteException {     dataSheet ds = new dataSheet();     ds.readExcel();     System.out.println("Hello");     ds.setValueIntoCell("sheet1",5,1,"PASS");     ds.setValueIntoCell("sheet1",5,2,"FAIL");     ds.setValueIntoCell("sheet1",5,3,"PASS");     ds.closeFile(); }   }


How to solve $\sum_{k=2}^\infty {\frac{1}{k^2-1}}$

I'm using the integral test to determine if this series converges. From what I have so far it seems that it diverges, but according to wolfram alpha it converges. Where is my mistake?   $$\sum_{k=2}^\infty {\frac{1}{k^2-1}} \to \int_{2}^M \frac{1}{x^2-1}dx$$  $$\int_{2}^M \frac{1}{x^2-1}dx = \frac{1}{2}\Big(\ln|M-1|-\ln|M+1|+\ln|3|\Big)$$  $$ \lim_{M\to \infty} \frac{1}{2}\Big(\ln|M-1|-\ln|M+1|+\ln|3|\Big)$$


If $P$ is real orthogonal matrix with $\det P = -1$, prove that $-1$ is an eigenvalue of $P$.    can anyone help me please how can I solve this problem?


Transit visa travelling from Canada to India via Germany

I have single entry tourist visa for Canada. My visa is valid till 20th Dec 2013 but I am travelling to Mumbai from Toronto on oct. end via Munich (Germany). I am an Indian passport holder. Do I need transit visa for germany? I will fly with Air Canada.


What do I get rid of to install Ubuntu when I have 4 primary partitions?

I am very new to Ubuntu and Linux in general, so any advice is appreciated. I am following the "Dual-Boot Windows 7 and Ubuntu in Perfect Harmony" tutorial on Lifehacker to do exactly that.  is the link. I am at the step of partitioning my system, I already have windows installed but i am in the Ubuntu Live. When i go into the GParted Partition Editor and try and select "new" I get this message:     It is not possible to create more than 4 primary partitions.      If you want more partitions you should first create an extended   partition. Such a partition can contain other partitions. Because an   extended partition is also a primary partition it might be necessary   to remove a primary partition first   Thats all!  Wow! Ubuntu's community is amazing, i was expecting at least a day wait for an answer. Anyways, here is the picture:    Also, i forgot to tell you, but i am on a laptop for this project, if that changes anything.  thanks for all of you help so far!


How to Compile Flash .fla into .swf via command line?

How to compile Flash .fla files into .swf via command line on a Windows based operating system.  Command line tools that need to be installed are ok. Can anyone suggest me what to do? (in a straight forward way).  :-) Thanks.


I would like to type on to a PDF document using LaTeX. Using the package pdfpages I can load the PDF in to a TeX document. Is there a way to also overlay my own text, using LaTeX? (In particular, a professor has generated a notes document and instead of printing and taking notes by hand I would prefer to take them directly on to the PDF, using TeX).


How do I solve the inverse sin without a inverse sin button with the equation $x = \sin^{-1}(0.5)$?

I am writing an expression in code where I am solving the angle where I know the Opposite $(2.5)$ and Hypotenuse $(5.0)$ and want to solve the angle. However, I do not have the inverse sin available. How do I solve the following equation without using the inverse sin function? $$ x = \sin^{-1}(0.5) $$ I know that $x$ will be $30^\circ$, I don't know how to solve the equation without the inverse sin function.


Prove $ \sum\nolimits_{n=1}^{ \infty } u_n(x)$ converges uniformly at $[0,1]$, when $u_n(x) = (-1)^n*(1-x)*x^n$

I can't understand how to prove that $ \sum\nolimits_{n=1}^{ \infty } u_n(x)$ converges uniformly at $[0,1]$, when $u_n(x) = (-1)^n*(1-x)*x^n$. I tried using Weierstrass M-test - bounding those functions with a converging series $ \sum M_n$, which will result in $ |u_n(x)| \leq \sum M_n$. But after 1 and 1/2 hours I couldn't find the right usage here. I'm aware of the other question linked to that, but it doesn't answer exactly the same thing. Would much appreciate help. Thank you!


Find an identical file with a different name

Is it possible to find a without knowing its name?   I created a file with LaTex, then I copied it into another local directory and renamed the pdf. I don't know any more where the original file is located, but I have the renamed file on hand. I would like to make some modification to my latex file and recreate the pdf.   Since I know the original file is exactly the same as the renamed one except for the name,  is there any way I can find my original file?


I saw a question while going through spotting error exercise.() Book says to replace even can't with can't even.   He has been going to office/ for a year now and/ he even can't understand its working/No error.   But even can't is also correct???


What methods are used to measure an objects temperature in kelvin? And what is the Rankine scale?

I know that temperature can be found as a quantity proportional to some quantity which increases monotonically with "hotness". And we can use various methods such as mercury column, gas thermometer and resistors to do so.  And by calibrating all of this to the different phase transistion states of water, we can get a uniform temperature scale.   Now my question is what method was used for defining temperature on kelvin scale? I've heard that it's based on energy of gases but how would you measure "energy" of a gas?  I have read the accepted answer to this question:    And he says kelvin used thermometers different fluids but what kinds and how? Also I see a rankine absolute thermometer scale. What is this?


Let $a,b,$ and $c$ be positive real numbers. Prove that $$\dfrac{1}{a^3+b^3+abc}+\dfrac{1}{b^3+c^3+abc}+\dfrac{1}{c^3+a^3+abc} \leq \dfrac{1}{abc}.$$   This question seems hard since we aren't given any information on $a,b,c$ except that they are positive. I tried cross multiplying by $abc$ and proving that $$\dfrac{abc}{a^3+b^3+abc}+\dfrac{abc}{b^3+c^3+abc}+\dfrac{abc}{c^3+a^3+abc} \leq 1.$$ Then we use AM-GM on the denominator. This didn't  seem to help me.


I think this issue has been going on for over a month now.  I boot my PC and the Adobe Updater tells me to download a new version of Flash. It sends me to  with the following information visible:     Version 11.9.900.152      Your system:      Windows, English   The Update Now button simply links to      I've cleared my cache, that didn't help. The Are you an IT manager or OEM links me to a page where I can either Apply to distribute Flash Player or Download Adobe Flash Player, the latter just sends me back to where I came from. I've uninstalled and rebooted, went to the Adobe website and clicked Adobe Flash Player under the Download menu. The Install now button again links me to  Need Flash Player for a different computer? sends me to  and the Download now button is greyed out and unclickable.   How can I update?


I don't think  deserved to get  deleted as spam. Martin'Vobr vas Rebex linked to a product he makes as an example of a library to accomplish the task the OP sought, and did so in a way that made it clear that he is the creator of the library and therefore his word should be taken understanding that he is biased.  Do you think he did anything underhanded in his answer? Here's the "spammy" part, for those without ten thousand arbitrary numbers:     I would try the code from the codeproject and if it suits your needs stick with it. In case of too many parsing problem the commercial email component with decent support could be a wise move. I would recommend our  ($149 single dev) but I'm biased. Feel free to browse for you own favorite ;-). At least it will be (in case of any problem) someone who is paid for solving your mail parsing problem.   Ordinarily I would flag this for moderator attention but unfortunately I am not permitted to flag locked answers. Also, I'd like to know if I'm completely wrong about my understanding of what is and is not spam.  To me, this isn't spam. To six other people, it is. One of us has to be wrong, by the pigeonholing convention of '57. Can we figure this out? There are a lot of similar users to Martin who post their products, and a lot of them do it in a very spammy way. But in the specific instance of Martin I think he does it well. We can't outright outlaw all users who advocate their own libraries, can we? Those might be the only libraries that do what the asker wants, after all.


vs2012 changed the default association of EXE files to notepad

EDIT: using the "change user" login screen, when reloging into the account, all icons are restored ok. So it seems the question is closed.  using the "view" menu item in the TFS dialog box to open an exe file (in TFS) i forgot to uncheck the "always open with" checkbox.  Now in Windows all .exe files are associated with the program i choose (notepad), and all icons of program files are the icon of notepad.  I managed to revert the default "open" action on .exe files so i can now run any program without opening notepad.  But i'm stuck with the notepad icons displayed on all my programs. I've deleted the iconcache.db file, and run a .reg file to "restore" default associations of EXE files in Windows 7. Rebooted. Nothing happens, notepad icon stays everywhere.  What registry key should i delete in my profile to get back the original icons for all .EXE files ?


I want to show that the diophantine equation does only have the trivial solution $x=y=0$. Since $\text{gcd}(73,-137)=1|0$ this is solveable. So  \begin{align} 137&= 1\cdot73+64\\ 73 &= 1\cdot64+9\\ 64 &= 9\cdot7+1\\ 7  &= 1\cdot7+0 \end{align}  So,  \begin{align} 0&=7-7\cdot1=7-7(64-9\cdot7)=7-7\cdot64+49\cdot9=7-7(137-73)+49(73-64)\\ &=7-56\cdot137+105\cdot73. \end{align}  But this is not in the correct form, the $7$ at the start bothers me and I cant get rid of it without ruining my $137$ or $73$.  How can I fix this?


Some basic questions about LaTeX/Advice on how to learn

I want to learn how to write math using LaTeX. I have a mac and have downloaded MacTex. I have used  and have learned the very basics of writing with MathJax and I liked how when I wrote, the displayed formula came up right underneath   I have tried producing this same equation in LaTeX and got numbered equations instead.     So my questions are:    How do I write without the (1) and (2) in LaTeX?  Can I/how do I program LaTeX to display the formulas typesetted nicely automatically (perhaps beneath the raw text, like in MathJax) instead of constantly clicking the Typeset button?  Where is a good place to learn (so far I have been using  to look how to write symbols I need).


somehow the alloy braking surface of my rear wheel's rim has got a series of quite shallow lacerations, less than a mil' deep bunched quite closely together (the effected area is no more than 1/8 of the rim).  When I brake (side pull road bike brakes) I can hear it making a different sound on each rotation has the damage goes past the pads.  The wheels are Reparto Corse's which came with my Bianchi, they are new and have less than 1k miles (probably way less). And they are fine in every other respect.  So I guess my options are:   Leave it and let it smooth out with use. May take some time and wear down brake pads faster. Lightly sand the worst offending parts with high grit abrasive paper. Fill the damage with expoxy (or similar) then sand. Replace the rim (would it worth the labour cost?)   So are any of these good options or do you have any idea what you may also do?  Thanks


I am creating a simple animation with fire in Blender Render. A followed a tutorial to make an animation with flames. The flames in the viewport but when I try to render my animation/image the flames don't show up. Where is my problem?


My current plotting tool for my papers is  for nice consistent plots. Now I would like to add a boxplot. Is this possible with help of pgfplots, or any helper package?


File sizes greyed out (strange extended attributes) in Finder on Lion?

I just got a new machine with Lion preinstalled. After transferring all my applications, I noticed that the file sizes (and only the sizes) of some applications and folders are greyed out:    Does anybody know what this means?  Update:  ls -la gives the following lines for DjView and Dropbox:  drwxr-xr-x   3 daniel  staff    102 31 Okt  2007 DjView.app drwxr-xr-x@  3 daniel  staff    102  3 Mai 10:06 Dropbox.app   I.e. Dropbox.app has extended file attributes, namely  $ xattr -p com.apple.FinderInfo Dropbox.app/ 00 00 00 00 00 00 00 00 00 00 FF FF FF FF 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00   Cheers  MrMage


When a public function accepts a float value, and this value is to be kept within a specific range, I usually do:  void setParameter(float p) {   if (p < 0) p = 0;   if (p > 1.f) p = 1.f;   // ...do something with 'p' }   Is there a better, faster, more elegant way to keep a float value in range?


Consider the following for loop in Javascript.  for( var i=0;i<10;i++){ } console.log(i);   If i run the code, I will get 10 in the console. Why is this? How is the scope of variable 'i' available outside for loop ?


I am currently working on a project. For this project, I would like to prevent items from stacking. Is there a way to do this with commands?


Removing large image files from production database

The database design for a retail organization has several tables with image columns. These account for around 40% of the table size due to their large size.  (Many a DBA issues come from inheriting the existing environment).  This is a production database.  I would like to know of a way to archive the current images from the database. Is there a better way besides FILESTREAM to  store or have access to image files than this?  I am thinking of a column with link to file system where the image is stored.  How does one get to that point? Can someone point me in the right direction


Run WinSCP script from bat file as different user

could anybody help me with this please: I can successfully call a WinSCP script from a bat file like this: "C:\Program Files (x86)\WinSCP\WinSCP.com" /script="script_file_path.txt"  I can also successfully open a program such as notepad as a different user like this: runas /user:my_user@my_domain "C:\Windows\notepad.exe"  However I cannot call a WinSCP script as a different user by doing this: runas /user:my_user@my_domain "C:\Program Files (x86)\WinSCP\WinSCP.com" /script="script_file_path.txt"  When I run the code, it does nothing. It doesn't prompt for a password, open WinSCP or run the script. If I add a pause at the end to see what is on the cmd screen it is a list of prompts and their descriptions for the runas command. Many thanks in advance. James


I have an idea of supersymmetry in quantum mechanics, can you suggest a book on "supersymmetry in quantum field theory", which has sufficient mathematical rigour like "Peskin and Schroeder"


How large can integers be in Javascript before roundoff error?

The code below:  function lookForMatches() {     for (var a=1;a<=2000;a++)     {         for (var b=1;b<=a;b++)         {             c=a*a*a+b*b*b;             d=5*c*c;             e=d-4;             f=d+4;             g=Math.floor(Math.sqrt(e))*Math.floor(Math.sqrt(e))             h=Math.floor(Math.sqrt(f))*Math.floor(Math.sqrt(f))             if (g==e||h==f)                 document.getElementById("matches").innerHTML+=c+" ";         }     }     document.getElementById("matches").innerHTML+="Done." }   is supposed to check for Fibonacci numbers in the sequence of the sums of positive cubes, but the output is:     2 5075441272 2976917960 7114243176 Done.   I ran the Fibonacci test manually in Windows Calculator, and although the square root of (5*50754412722±4) is extremely close to an integer value, it's definitely not an integer! I'm not even certain if the number 5075441272 is actually a valid sum of cubes. How large can integer values be in Javascript without introducing roundoff error?


How to record how much time user has spent on my node?

I want to record the time a user has spent on my particular node so I could show a pop up to the user to register once the user has read 3 article. But the user must have spent at least 30 seconds on each node.   There is the  module available, but I wonder if I can merge it with another (custom) module I have created (which records the number of nodes user have visited)?


Trying to install from instructions on:  and I get:  $ kirby@kirby-Aspire-ES1-433:~/Downloads/rtl8192EU_linux_v4.3.1.1_11320.20140505$  sudo dkms add Error! Invalid number of arguments passed. Usage: add <module>/<module-version> or        add -m <module>/<module-version> or        add -m <module> -v <module-version>   How to do correctly sudo dkms add?  I tried also:   kirby @kirby -Aspire-ES1- 433 sudo add-apt-repository ppa hanipouspilot/rtlwifi    [sudo] password for kirby   This is ppa for Realtek drivers from Larry Finger's GitHub.    rtl8192eu is packaged from the Realtek site with some compat patches   . More info   : https   : //launchpad   . net /~hanipouspilot/ + archive /ubuntu/ rtlwifi Press [ENTER] to continue   or Ctrl -c to cancel adding it.    Hit:1 http://hr.archive.ubuntu.com/ubuntu bionic InRelease Ign     Get:2 http://ppa.launchpad.net/hanipouspilot/rtlwifi/ubuntu bionic InRelease        Get:3 http://security.ubuntu.com/ubuntu bionic-security InRelease [ 83, 2 kB ]        Hit:4 http:// hr . archive . ubuntu . com / ubuntu bionic-updates InRelease      Hit:5 http:// hr . archive . ubuntu . com / ubuntu bionic-backports InRelease Err   : 6 http   : //ppa   . launchpad   . net /hanipouspilot/rtlwifi/   ubuntu bionic Release 404 Not Found [ IP : 91.189.95.83 80 ] Get   : 7 http   : //security   . ubuntu   . com / ubuntu bionic-security / main amd64 DEP-   11 Metadata [ 204 B ] Get:8 http://security.ubuntu.com/ubuntu bionic-security/universe amd64 DEP-11 Metadata [2 452 B] Reading package lists... Done                    E: The repository 'http://ppa.launchpad.net/hanipouspilot/rtlwifi/ubuntu bionic Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. kirby@kirby-Aspire-ES1-433:~$ sudo apt update Hit:1 http://hr.archive.ubuntu.com/ubuntu bionic InRelease                      Hit:2 http://hr.archive.ubuntu.com/ubuntu bionic-updates InRelease              Hit:3 http://security.ubuntu.com/ubuntu bionic-security InRelease               Hit:4 http://hr.archive.ubuntu.com/ubuntu bionic-backports InRelease Ign:5 http://ppa.launchpad.net/hanipouspilot/rtlwifi/ubuntu bionic InRelease Err:6 http://ppa.launchpad.net/hanipouspilot/rtlwifi/ubuntu bionic Release   404  Not Found [IP: 91.189.95.83 80] Reading package lists... Done E: The repository 'http://ppa.launchpad.net/hanipouspilot/rtlwifi/ubuntu bionic Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.  kirby@kirby-Aspire-ES1-433:~$ sudo apt install rtl8192eu-dkms Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package rtl8192eu-dkms   What is wrong?


How to calculate the height of a header in  tag?

How do I calculate the height of a <header> tag from a <main> tag so that I can use the calc() function to calculate the rest of the screen space available to span a banner in its place.  HTML:  <body>   <header>     <!-- A Navigation Bar of some sorts -->   </header>   <main>     <div class="banner">       <!-- Some text on the banner -->     </div>   </main> </body>   And CSS:  .banner {   height: calc(100vh - /* Height of <header> */);   background-image: url(some image);   background-position: center;   background-size: cover; }   Just an FYI... I'm designing for a project for college and for mobile specifically so this formatting will not span to desktop as I will change the styling for desktop and tablets


What is the formula to solve a cubic equation?

I know that to solve $$ax^2+bx+c=0$$  you have to use the formula $$x=  \frac{-b \pm \sqrt{(b^2-4ac)}}{2a}$$  What about more complex ones, like $ax^3+bx^2+cx+d=0$? And what about representing it on a cordinate plane, $2D$ or $3D$?


Showing $2^n -1$ is composite when n is composite

I'd like to show that if $n$ is a composite number, then so is $2^n-1$.  When $n$ is an even number, this is simple. Let $n$ = 2k. Then, $2^n -1 = (2^k)^2- 1 = (2^k -1)(2^k + 1)$.  For the case where $3|n$, this is also not too hard. For $n = 6$, we have $2^6 -1 = 63 = 7 \cdot 9$.  Assume $7|(2^{3k} -1)$. Then, $2^{3(k +1)} -1 = 7\cdot2^{3k} + (2^{3k} -1) $ which is divisible by 7. So, we can show that this case also leads to a composite number via induction.  However, I can't seem to generalize it for an arbitrary $n$. Any hints to the right direction is much appreciated.


Comma usage with Provided or Provided that

So I was checking the general usage of commas with conjunctions, and saw the inconsistent case of "provided" or "provided that". Example:   You can drive a car provided that you have a valid license.  You may produce your own version of the form, provided that the content is the same as in the attached template.    Why does one of the sentences get a comma, and the other one doesn't?


In a preadditive category, products are coproducts

$\renewcommand{\phi}{\varphi}$ $\require{AMScd}$ My question is different from .  I want to see how in a preadditive category $\mathcal{C}$ a product is a coproduct, following . I'll write the proof up to the point where I get stuck.  Let $A=A_1,B=A_2$ be objects and suppose their product $P$ does exist, with projections $\pi_i:P\rightarrow A_i$. By considering a wedge  $$\begin{CD}A @<{id_A}<<  A @>{0_{AB}}>>  B\end{CD}$$  and the obvious analogous one with $A$ and $B$ exchanged, where $0_{A,B}$ is the zero morphism, we see that the product property implies the existence of two unique morphisms $k_i\in\mathcal{C}[A_i,P]$ s.t.  \begin{align*} \pi_j\circ k_i=\begin{cases} \mathrm{id}_i &\text{if }i=j\\ 0_{A_i, A_j} &\text{if }i\neq j \end{cases}. \end{align*} Using these equations and the definition of zero morphism, it's easy to see that the morphism $m\equiv k_1\circ \pi_1+ k_2\circ \pi_2$ satisfies $\pi_i\circ m=\pi_i$.   This is where I get stuck: In the linked proof, they now state that this implies $m=\mathrm{id}_P.$ But I don't see why this should be true.   Specifically, if $\phi\in\mathcal{C}[S,P]$ for some arbitrary object $S$, it is not apparent why $m\circ\phi=\phi$. All that we know is that there are some morphisms $x_i\in\mathcal{C}[S,A_i]$ that factor through $P$ via the universal property, but these are not necessarily unique.  And we learn even less about $m$ by looking at morphisms in $\mathcal{C}[P,S]$.  What am I missing here?


Probability of n points on one semicircumference

Given $n$ random points on a circumference, what is the probability of them lying in the same semicircumference?  Feedback on my solution and/or alternative solutions would be appreciated.  EDIT This is a duplicate of math.stackexchange.com/q/18369/27978


Why are there parallel technologies in the Star Trek universe?

Is it ever explained why so many races evolve, technologically speaking, on a nearly parallel course in the Star Trek universe? Obviously their physical and social evolution was far from parallel but technologically nearly every space faring civilization evolved along nearly identical lines.    I know every race developed technologically at different rates, a few are thousands of years more advanced, but the similarities are undeniable. I also know that some races were gifted technology by other, more advanced civilizations and some stole tech to further the advancement of their own.  Is this just a subtle plot point within the Trek universe to avoid multiple technology theories? As such does it make it easier to say everyone above a specific technological checkpoint have similar tech?


How to undo manual installation of Python 2.7.18 on Ubuntu 18.04

I used the following tutorial to install Python 2.7.18 on my Ubuntu 18.04 machine:  After installing, I realized that I have in effect done a manual install outside of apt. If I'm not mistaken, this seems like a recipe for trouble. Entering python --version continues to return Python 2.7.17, reflecting the potential issue. Is there a way I can uninstall Python 2.7.18? I'm hoping the installation steps in the attached tutorial might help figure out how to remove it. Thank you!


Multiply a string by itself in javascript

In python to get an array of X strings (repeated) I can do: >>> 'hi' * 3 # 'hihihi'  Perhaps 'array' isn't the correct term but hopefully the above example clarifies what I mean. Is there a way to do this in javascript without using a loop? Or what would be the most straightforward way to do this? Currently I'm using a c-ish loop: > for (let i=0, x=''; i< 3; i++) {x += 'hi'} // "hihihi"


Why are we allowed to decompose a function of two variables $f(x,y)$ into the form $\sum_n^\infty c_n(y)\psi_n(x)$?

I apologize if this is more mathematical than physical, but this issue always seems to come up when I am solving physics problems.   Given a function of two variables $f(x,y)$ let us decompose it into an infinite series of orthogonal functions $\psi_n(x)$ such that $$  f(x,y) = \sum_n^\infty c_n(y)\psi_n(x) \tag{1}$$ and so $$ c_n(y) = \int_a^b \psi_n^*(x) f(x,y)\ dx\tag{2}$$  My question is simply how are we always allowed to decompose a function of two variables as the product of two variables (and then sum over varying products). Is there any sort of non-rigorous proof as to why this can always be done? I've used this fact many times, but I have never seen any explanation as to how/why we can so trivially separate them.


Is there a way to either pipe the sound output of the computer to a file or record what the computer puts out? I know I could use a headphone to microphone cord, but I was hoping for a more elegant solution. Google doesn't give very good results.


Is there a way to log changes to module settings for better long-term administration and debugging?

We run quite a complicated Drupal 6 site with a lot of custom modules which was already migrated from D5. There are a few site administrators and we have had situations where a change in the settings of one module (usually something conflicting with Boost) has caused a problem with the site that is only detected later. We have no way to quickly tell which settings have been changed recently and what their previous values were.  Is there an additional module that hooks into to all variable_set() calls (for example) and logs the old and new values so that we can have an admin view listing all changes over time and which user made the change? It would be great to have an option to add a note to each item to explain why the change was made?  We try and share notes in our wiki on such changes but I think it would be much better if such data was available from inside Drupal itself.


What tests can I do to ensure my random number generator is working correctly?

In the past I have used the Chi-squared test to check the statistical randomness of my generator. Is this a good test to use? Are there other tests?


Ok I was getting ready to wire a ceiling fan and wasn't sure which switch it was going to.  I connected the hot coming in to one of the switch legs to use my tester.  Now keep in mind the other switch leg was not connected on both ends.  To my surprise the switch leg not hooked up was reading hot.  Any suggestion on what the issue would be?


How to move modifications in Napili template to production?

I have modified some changes in both lightning components and a community site which is built on Napili template in the sandbox. How can I move the changes from sandbox to production, Is it possible to do with change sets?


\documentclass{article} \usepackage{graphicx} \usepackage{hyperref}  \begin{document}    \begin{figure}     \href{http://commons.wikimedia.org/wiki/File:Pachydyptes_ponderosus.jpg}          {\includegraphics[width=\textwidth]{picture}}     \caption{A reconstruction of New Zealand Giant Penguins (\emph{pachydyptes ponderosus}) by        F.~W.~Kuhnert (1865--1926). Click on the image to visit the page on Wikimedia Commons where it        was downloaded from.}   \end{figure}  \end{document}   This is the correct code. But it becomes black image. Is there any problem


What does it mean when you use the "d" in a derivative as a variable?

It's been over 15 years since I last did anything with calculus at school, and I've forgotten most things, so please be gentle with your answers. :) One thing that has always bugged me when getting into more advanced stuff was that the derivative simbols are suddenly manipulated in a way that doesn't make sense to me. For example, let's take the simple equation $$y=12x^2+24x+45$$ An alternative notation for the same thing would be: $$f(x)=12x^2+24x+45$$ Here we merely substituted $y$ for $f(x)$. It means the same thing. If memory serves me right, when we take the first derivative of this function, we have three ways we can write it: $$y'=24x+24$$ $$f'(x)=24x+24$$ $$\frac{dy}{dx}=24x+24$$ Now, it's this third notation that I'm talking about here. To my understanding the $\frac{dy}{dx}$ doesn't really mean anything by itself. It's just another way to specify that we're talking about a derivative of a function, just like the $'$ in the other two notations. But then sometimes I come across an equation : $$m\frac{\text{d}^2\mathbf{r}}{\text{d}t^2} = \frac{kqq'}{|\mathbf{r}|^2},$$ And here suddenly the $d$ is being treated like a variable, not to mention the $t$ and... And if memory serves me right, I've seen ever more extreme examples where the fraction $\frac{dy}{dx}$ itself is taken apart and each of the components used as a variable. I think this was popular back in university when I was talking course on differential equations. Barely passed that, half of it didn't make sense, and this was a large part of the reason why. I don't remember why I never asked my teacher about it back then. So... what does it mean when we start to break the $\frac{dy}{dx}$ apart?


Prevent the Fall Creator's update from downloading automatically

For the last 4 days, Windows 10 has been trying to apply the Fall's Creator Update to my computer. After the first succesful update, I noticed the peformance of my PC went down considerably, so I rolled back to the previous Windows version. However, next day, my PC started downloading the update on it's own again withotu my will, forcing me t0 update and roll back once again. This's been going on for the last 4 days and it's getting quite annoying to deal with.  Is there a way to stop Windows 10 from trying to apply this update, hopefully for good? I've got Windows 10 Home 1703 if it helps.


Please help I’m very confused about this. If $[r]$ and $[s]$ are two cosets of the set $R/A$ (Where $A$ is an ideal of the ring $R$) why are we allowed to define $[r]*[s]=[rs]$ when we only know that $[r]*[s]$ is a subset of $[rs]$?


Make it cost more to downvote without comment; make it hurt to leave a crap comment

Possible Duplicate:    In the spirit of "encouraging" people to leave comments on downvoting, I would propose that if someone downvotes without a comment, I propose a heavy point tax, say 3x the current point cost for a downvote. If he or she downvotes and leaves a comment, then it costs the current amount. If someone leaves a crap comment (to avoid the "charge") they get a painful spank (100 points gone or whatever the community decides) if and only if:  The comment is flagged Three (five? whatever) moderators agree it is crap  Common complaints Or, why my proposal is different.  "  a "   No it isn't. I specifically address the issue of leaving garbage comments to avoid the downvote tax, unlike the other proposals.   "Some people want to leave anonymous (down)votes."  I understand that some might be fearful of retaliation. Is retaliation a real problem or a "what if" conjecture? (Where's the data?) What if we try it for 3-6 months and then circle back to see how well it works?  If a user starts retaliating against another user, they will be dealt with as are all other problem users. Nothing else is anonymous - asking questions, answering questions, editing questions, leaving comments, etc. and there is a clear benefit. What is the benefit to the community for having anonymous voting? I would argue "none." Even though some people might want to leave anonymous questions, answer anonymously or anonymously edit a question, it is not allowed, because it is not good for the community.   "But this will discourage downvoting"  I agree, and I think that's a good thing, which goes to the philosophy of the site: promote good questions and answers. If a question or answer is poor, few will up-vote it. If is is really poor, it will get flagged and . If someone really wants to downvote, no one is stopping him or her. Just as we want quality questions and answers, we need quality voting.   It will require too much work to implement  Maybe. Let's ask if it is worth the effort. What benefit does anonymous, no-comment downvoting add to the site? It certainly doesn't allow the author to improve. What benefit would owned, commented downvoting add? It would hopefully allow authors to improve and discourage drive-by downvoting. Would me (or someone else) submitting a patch alleviate this complaint?   Jeff (or Joel) thinks this is a stupid feature, and you're stupid for suggesting it.  "" Is this a true statement?    Thanks for reading.


Want to unique number out of my file read | error - java.lang.NullPointerException

I am not sure my i am getting NullPointerException exception i am new to java can anybody please help on this.     Code i am using for this -    import java.io.BufferedReader; import java.io.FileReader; import java.io.IOException; import java.util.Collections; import java.util.HashSet;  public class sortNumberOfFile {     public static void main(String[] args) throws IOException,             InterruptedException {         HashSet<String> hs = null;         String perLine;         String filename = "C:\\Users\\dummy\\Downloads\\ip.txt";         BufferedReader br = new BufferedReader(new FileReader(filename));          while ((perLine = br.readLine()) != null) {             System.out.println("whole line : " + perLine);              String[] eachLine = perLine.split(",");             System.out.println("custom element " + eachLine[0] + " "                     + eachLine[2] + " count " + eachLine.length);              for (String str : eachLine) {                 System.out.println("Adding "+str);                 //Thread.sleep(2000);                 hs.add(str);             }  //          Collections.addAll(hs, eachLine);             System.out.println(hs);          }     }  }   Console Output i am getting -   whole line : 1,2,32,4,5,234,6,12,3,67,3421,123,2,2,34,5,4 custom element 1 32 count 17 Adding 1 Exception in thread "main" java.lang.NullPointerException     at org.gour.indrajeet.practice.sortNumberOfFile.main(sortNumberOfFile.java:27)


Asimov's story where a man's speech contains no information

I am trying to remember the name of a tale or novel by Isaac Asimov. I am positive I've read this some years ago, but for the life of me, I can't recall the name.  In the story, one of the characters, some kind of diplomat, speaks profusely. Only after recording and analysing his speech, the main character(s) come to the conclusion that there is no actual information to all his verbosity. He was a master at speaking without actually saying a thing.


What does $\frac{dy}{dx}$ mean in calculus?

In calculus, does $\frac{dy}{dx}$ represents the slope of a function? If so, what does $d$ in the numerator represents in $\frac{d}{dx}$? And why does $\frac{d}{dx} y=\frac{dy}{dx}$?


if a is not an element in a list how to print?

So i created a list like this:  my_list = [1, 3, 5] number = input("Choose a number from 1 to 5: ")   Now I want to say:  if the number is inside the list: print("ERROR"), if the number is not inside the list: print(number)  So if I type 2 it will print me the 2, if I type 1 it will print me ERROR   How am I doing that?


As every American teenager "knows" there is no speed limit on the Autobahn. My understanding, however, is that there is still such a thing as excessive speed even on this free-for-all.   So, ignoring the practical "don't be an idiot" and "don't drive faster than you can handle," at what speeds would die Polizei be pulling you over?  Bonus points for translating km/hr into miles/hr.


Not able to connect to Oracle Database through UI Path getting error "Oracle client software version 8.1.7 or greater". Can anybody help me?

I am trying to connect to Oracle Database through UI Path but I am getting the below error.  "Connect: System.Data.OracleClient requires Oracle client software version 8.1.7 or greater." After going through all the question on google, I got to know that Oracle installation will get the issue resolved but I have installed 'Oracle 12c' in my system but still facing the same error.  Is there any other solution to it?  Or do we have to give any specified path to UIPath to points towards Oracle? Not sure why the issue is coming up?  Is there anyone who faced the same issue and able to resolve with some solution?  I have tried installing Oracle Client 12c, suggested by almost everyone but the issue still not resolved.  Error Message:     12:40:45.7497 Error {"message":"Connect: System.Data.OracleClient requires Oracle client software version 8.1.7 or greater.","level":"Error","logType":"Default","timeStamp":"2019-04-20T12:40:45.7497423+02:00","fingerprint":"f46d089f-69d7-4c8f-b154-891952bbe98e","windowsIdentity":"WSINT\svc_ae_robocrm_1","machineName":"DEHERWSVWWS124","processName":"OracleDB","processVersion":"1.0.0","jobId":"16e75fda-c1e4-4b6a-ade7-9379293173ff","robotName":"WSINT\SVC_AE_ROBOCRM_1","machineId":0,"fileName":"OracleDBExecution"}


Word for people who buy things because they are more expensive/ for the brand

Is there a word for people who buys things because they are more expensive or because they are specific brand or label?  These people don't buy the items because they are higher quality. They buy them because they want others to think they are "cool." These people can often hardly afford such items and this money could be better spent on other items.  This is opposed to other people who might buy more expensive things because they are of better quality. (Who would rarely buy popular brands because their prices are inflated simply because they are popular.)


Downloading Ubuntu, why its shows "amd64"

I am downloading Ubuntu 16.04.2 LTS when I click on download, then it's shows "amd64"  somewhere in the name of file like "ubuntu-16.04.2-desktop-amd64.iso"  , What does it mean? Is this not for Intel processors?


Show that the set of products need not be an ideal

Let $R$ be a commutative ring, and $I$, $J$ be two ideals in $R$.  Show, by giving an explicit example, that the set of products $\{xy\ |\ x\in I, y\in J\}\subset R$ need not be an ideal.  The definition of "ideal" we're using is:     An ideal is a subset $I$ of a commutative ring $R$ that satisfies the following properties:      1) $0\in I$.      2) If $x\in I$ and $y\in I$, then $x+y\in I$.      3) If $x\in I$ and $a\in R$, then $ax\in R$.   The set of products will contain $0$, so property 2 or 3 has to fail. I can't come up with an example. Any suggestions?


What did Leto do to earn the enmity of the Padishah Emperor?

Leto Atreides seemed an open and honorable man.  Yet the Padishah Emperor conspired with House Harkonnen to deliberately betray Leto, and destroy House Atreides.  Why?


Question regarding the square root of a squared number.

I've learnt that the square root of a number squared is equal to the absolute value of that number, but I haven't really understood why. I have looked through other questions on MSE but didn't really find a good answer.  As an example: for me there are two ways to arrive at a solution for $\sqrt{(-5)^2}$  First: $\sqrt{(-5)^2}= $ $\sqrt{25}=5$  Second: $\sqrt{(-5)^2}= $ $\ (-5)^{\frac{2}{2}}$$\ =(-5)^1=-5$  but according to the $\sqrt{x^2} = | x | $  rule 5 is the only solution. What is the flaw in my logic in getting -5 as a solution. I would really appreciate a comprehensive explanation that clears this up. Thanks in advance.


How to express happiness on someone's failure?

Documentation of StackOverflow is finally gone, and I am happy about it. StackOverflow was meant to be a Q/A site, and it is, in fact, the top site in its category. But Docs is not something it should be doing. Every project have their own documentation which is good in itself.   I want to express the feeling that I'm happy it is gone. Happy is so generic for this. Grin is also not one of it. Please also note that I have a negative context.   And please, I really like SO, I don't hate it. I just want to improve my vocab.  EDIT:  This question is not as same as  because that question completely different. It deals with happiness which is caused by the success of others, and this question is more like happiness in the failure of others.


Removed post gives me -2 reputation. What happened?

I deleted an answer which had no upvotes or downvotes, but after some time I saw that my reputation was -2 and the reason is linked to my search engine.    I want to know why this happened and what "linked to my serach engine" means?


I am trying to create a PWM signal using a POT from 555 Timer to control speed of a 5V DC motor. I have a development board with a C8051F020 microcontroller, a 100K POT and an LCD display. The requirement is to generate PWM signals externally so that the microcontroller is free to do other things that needs to be done for the project. I need to use the DAC from the microcontroller to drive the 555 Timer.   Scenario: The ADC on the micro reads the value from the POT (present on the Dev board). The DAC converts it to an analog value which can be used by the 555 Timer. I cannot directly connect the pot to the Timer.  My understanding is that the ADC and DAC do not have to be physically connected together on the board. Instead the digital values sampled from the ADC can be used by the DAC through software, am I right? So my question: is it possible to connect the DAC of the microcontroller to the input (pin 7) of a 555 Timer with a level converter from 3.3V (DAC) to 5V (Timer) in between?  EDIT 4th Feb 2014  I am using LM741 OPAMP as a comparator. The Timer is configured in an astable mode. For prototyping purpose, the DAC from the microcontroller is replaced with a 100K potentiometer. Since the DAC is supposed to be the reference voltage to the comparator, I found that the LED would always light up (although very dim) because of the capacitor C1 voltage goes from 1/3*Vcc to 2/3*Vcc which is why the LED was dim because the lowest voltage was 1/3*Vcc = 1/3*5 = 1.67V. So I switched the terminals for the comparator and now the reference voltage is C1 (capacitor voltage) as shown in the schematic below. My questions:  1) Is it alright to replace DAC with a potentiometer to represent DAC voltage as the voltage from the POT? 2). Is it wrong to switch the terminals around? I tested it with inverted terminals and the LED completely switched off and glows bright when the DAC voltage (POT) is turned high up. Also tested with the motor. When the DAC is the reference voltage (pin 3 of LM741) then the motor starts up slow and cannot be stopped although the POT is all the way down. And when connected as shown in the schematic, then the motor is stopped in the beginning.


Class differences in isinstance() in python3 vs python2

Could someone please explain the following behaviour difference?  class a():     pass class b(a):     pass   In Python2:  >>> isinstance(b(),type(a())) True >>> isinstance(a(),type(b())) True   In Python3:  >>> isinstance(b(), type(a())) True >>> isinstance(a(), type(b())) False


Distributing $60$ identical balls into $4$ boxes if each box gets at least $4$ balls, but no box gets $20$ or more balls

How many different ways can the balls be placed if each box gets at least $4$ balls each, but no box gets $20$ or more balls?  I was thinking about finding all the possible ways which every box gets at least $4$ balls which would be $47\choose44$ ways $\rightarrow$ $16215$ ways. Then subtracting that number by the number of possible ways that a box could get 20 or more balls ($16215$ - $20$ or more balls possibilities). The thing is I don't know how to get the number of ways if a box gets $20$ or more balls. Any tips?


Make people understand they can click on a button in a flat design

I'm creating a flat-ish responsive website, which basically is an online résumé.  I'm displaying skills (but it could be whatever) in a grid system. Each skill is clickable, to display some information about it (level, etc.).  Here is a screenshot (from a mobile device view) of what I've made at this point.   I know, as the conceptor of the design, that it is clickable. However, I feel like it is not obvious - or not enough at least - for any random user.  On a computer browser, it is easy to have visual change on hover, but on tablet / mobile, I can't figure out how to do.  Does anyone has a visual trick to basically say hey, click on me? I think I could add a little pointer in the corner of each tile but I'm not sure it would look good.    UPDATE  According to some suggestions, I have changed icons to be more relevant. Thus, I can delete the label.  I also lighten a bit the background-color of buttons, in order to accentuate the constrat between the two shades of blue.


Can't use multiple extensions with "find"

I write a script to delete all types of archives from the last weak. My script is this and it works: list=$(find $1 -name "*zip." -mtime -7) for x in $list do rm -i "$x" done   The problem is when I try to add another type of archive like: list=$(find $1 -name "*zip." , -name "*.tar" -mtime -7) . It works just for .tar archives.


Can you use Minor Illusion to create an illusion of a working mirror, i.e. with reflection?

Can you use Minor Illusion to create an illusion of a working mirror, i.e. with a working reflection?


Can a UK visa ban affect an Ireland visa application?

I was issued a 10-year ban by the UK 4 years ago. Unfortunately, I answered no to the question of 'Have you been refused a UK visa before?' . It was a genuine error on my part when I was filling out the online visa form as I have gotten several UK visas even after refusals before.   Is there any likelihood of getting a UK visitor visa if I reapply? Or what can I do to overturn the ban? Can the UK ban affect my getting an Irish tourist visa in any way?


Return keys and values of object when matching with argument

Aim is to build a function, which takes an array of Objects as first arguments. As a second argument it takes a key and value pair.   function whatIsInAName(collection, source)   Now the function should return an array with all the matching keys and values from the object. For example:  whatIsInAName([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" })´    should return   [{ first: "Tybalt", last: "Capulet" }]  And  whatIsInAName([{ "apple": 1, "bat": 2 }, { "bat": 2 }, { "apple": 1, "bat": 2, "cookie": 2 }], { "apple": 1, "bat": 2 })   should return   [{ "apple": 1, "bat": 2 }, { "apple": 1, "bat": 2, "cookie": 2 }]   I tried looping through the collection- and through the source array searching for matches. Like this:  function whatIsInAName(collection, source) {   // What's in a name?   var arr = [];   for (var i = 0; i < Object.keys(collection).length; i++) {     for (var j = 0; j < Object.keys(source).length; j++) {       if (collection[i].last === source.last) {         arr.push(collection[i]);       }     }   }   console.log(arr); }   And in case of this arguments whatIsInAName([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" })  It not surprisingly works.   What I don't understand is, why I can't generalize the above solution, so that it also works in other cases.  Why is it not possible to simply give the condition:  if (collection[i] === source)   (Pls notice the missing "Last" key behind collection and source.)  When I console.log(source), console logs it. So imho the conditional statement above should work and should go to push the matches into the arr Array.   How can I build a function which returns an array with all the matching keys and values from the object.   function whatIsInAName(collection, source)   And why does (collection[i] === source) not work?  Thank you.


What's wrong with using a wildcard in your mySQL query?

Basically what's the difference in terms of security and speed in these 2 queries?  SELECT * FROM `myTable`   and   SELECT `id`, `name`, `location`, `place` etc... FROM `myTable`   Would using * increase the benchmark on my query and perform slower than static rows?


Retrieve combined records' fields values based on another field in the record using SQL

I want to combine records' fields values (to be comma separated) based on another field in the record. To get the issue better, kindly check the example below, I tried to simplify the scenario as much as possible  I've the following table, assume it is called 'My_Table'  +------+-------+ | Key  | Val   | +------+-------+ | A    | 5     | | B    | 8     | | A    | 7     | | C    | 4     | | B    | 8     | | B    | 9     | | C    | 6     | +------+-------+   I need a query to retrieve the following table   +-------+--------+ | Key   | Vals   | +-------+--------+ | A     | 5,7    | | B     | 8,9    | | C     | 4,6    | +-------+--------+   Kindly note that [B, 8] exists twice, I don't want the result to be  +-------+--------+ | Key   | Vals   | +-------+--------+ | A     | 5,7    | | B     | 8,8,9  | | C     | 4,6    | +-------+--------+   PS, I'm using MySql if it matters.    [UPDATE] BTW, it's not a duplicate question, the extra piece of info is solving the duplication


HI am trying to use CAML query to pull the data of list based on date range and I am unable to pull the data with the query i am using.  I have column name as 'created' and which is for both fromDate and toDate where the dates are used . My date format is "Wed May 6 16:40:23 EDT 2015" My query part Am trying is this. how to get my date range work. can someone help me out with this.  camlQuery.set_viewXml('<View><Query><Where><And><And><Neq><FieldRef Name="ID" /><Value Type="Number">0</Value></Neq><FieldRef Name="_ModerationStatus" /><Value Type="ModStat">0</Value></Eq></And><Eq><Geq><FieldRef Name="Created" /><Value IncludeTimeValue="FALSE" Type="DateTime">" + Iso8601toDate + "</Value></Geq><Leq><FieldRef Name="Created" /><Value IncludeTimeValue="FALSE" Type="DateTime">"+ Iso8601fromDate +" </Value></Leq></And></Where><OrderBy><FieldRef Name="_ModerationStatus" Ascending="True" /></OrderBy></Query></View>');


When finding outliers from the Interquartile range why I have to multiply by 1.5?

I was looking at the outlier detection formula which uses the IQR and I wonder why it should be multiplied by 1.5? Can the constant be increased i.e 3 or 6 to be more "acid" if so under what criteria?


Why doesn't the parseInt() method work in this case (returns NaN)

Here's a basic function in JavaScript which should convert an array of numeral strings into an array of integers.    function convert(arr) {   return arr.map(parseInt,10); }     The result of running     convert(["1","2","3","4","5"]);     should be to return     [1,2,3,4,5]     .  However the function returns:     [1, NaN, NaN, NaN, NaN]     I know that if the parseInt() function encounters a character which is not a numeral, it returns NaN.  I also know that the method will work if the Array.prototype.map() function is replaced with a conventional for () loop, so the culprit seems to be the .map() function.  Does anyone know why .map() works normally on the first indice in the array but does not work on the others?  Thanks.


I am replacing string content as:  re.sub(all, val, parsedData['outData'])   where all contains some round braces and might contain other characters.  >>> print all PICDSPVERS="DspFw:1.0008(1.0008),Fpga1:2.0925(2.0925),Fpga2:1.0404(1.0404),Mcu:1.0000(1.0000)"  Because of which matching fails. The pattern is coming from some interface, so I don't want to put \\ in the data.  I tried with 'r' and re.U option also, but still the match fails.  re.search('PICDSPVERS="DspFw:1.0008(1.0008)', parsedData['outData'])   How can we direct Python to treat a matching pattern as a string?  I am using Python 2.x.


Are there any theoretical limits on the energy of a photon?

Is there any lower or upper limit on the energy of a photon? i.e. does the mathematical framework we currently use to study photons blow up when a photon surpasses a certain upper limit of energy? (or the same on the opposite side?)  My thoughts: If I let the energy of a photon tend to infinity, its wavelength would be tending to zero, and since it is thought that we cannot really distinguish things when they are on the scale of a Planck Length, would the photon have its maximum energy when its wavelength is equal to the Planck length? (Feel free to correct me, I feel I might not be.) and for the opposite end of the spectrum a photon with the least energy would have zero wavelength, implying no photon, which is a trivial case.


How can I remove malicious spyware, malware, adware, viruses, trojans or rootkits from my PC?

What should I do if my Windows computer seems to be infected with a virus or malware?  What are the symptoms of an infection? What should I do after noticing an infection? What can I do to get rid of it? how to prevent from infection by malware?   This question comes up frequently, and the suggested solutions are usually the same. This community wiki is an attempt to serve as the definitive, most comprehensive answer possible. Feel free to add your contributions via edits.