Ppening an HTML file on localhost in XAMMP/apache 2.2 using subdirectories under htdocs
How do I run a file on localhost?
How to get domain name from URL Looking for an intuitive explanation why the row rank is equal to the column rank for a matrix I am looking for an intuitive explanation as to why/how row rank of a matrix = column rank. I've read the proof at  and I understand the proof, but I don't "get it". Can someone help me out with this ?   I find it hard to wrap my head around the idea of how the column space and the row space is related at a fundamental level. When I shoot a ball vertically upward, its velocity is decreasing since  there is a downward acceleration of about $9.8\,\mathrm{ms}^{-2}$.   I have read that at the top most point, when $v = 0$, the acceleration is still $9.8\,\mathrm{ms}^{-2}$ in the downward direction where $v=0$. That is, the acceleration is still the same.  But at the highest point, the ball is stationary, so it is not even moving. How can it accelerate? Which direction will the yoyo move? Prime factorizations of consecutive numbers, can they both contains powers of greater than or equal to $1000$? Just beginning to learn quantum mechanics and my textbook says that all pure eigenstates of the Schrodinger equation ( with a specified potential function) have a zero standard deviation for the expectation values of energy.So every measurement of the energy yields a fixed value. I've also read that pure eigenstates are physically realisable solutions in some situations ( like the infinite potential well). But wouldn't that violate the uncertainty principle? the standard deviation in expectation of energy is zero and hence $$ΔE~Δt=0.$$ Where am I going wrong? Also could someone also give me an insight as to what uncertainty in time even means? I haven't been able to grasp that concept clearly yet. What's the term in music, where the singer uses words without meaning? I've been searching for the word, which is used for describing parts of lyrics, where the singer sings for example the whole refrain only using words of syllables without any meaning. Maybe you could help? (here's one song with that type of refrain: ) What is the function of the "Sticky edges" on/off setting in displays? I have installed Ubuntu 12.04 (Precise Pangolin). If I open System Settings &gt;&gt; Displays there is a new (?) on/off button for a setting named Sticky edges.  Can someone tell me what this setting is supposed to control? Stack Exchange doesn't allow me to answer protected questions because I gave away earned rep in bounties I noticed that I can't answer protected questions. I don't want to actually, but it says:        It was , but I also didn't have an ability to answer other protected questions.  I earned 270 reputation points + 100 reputation point bonus. Then I  350 reputation points as a bounty. Then I earned 59 reputation points. Today I started another bounty (50 reputation points), etc – I offered 4 bounties with total 500 rep.  Despite the fact I started from the association bonus, I must have an ability to answer protected questions, as I earned reputation points here. But offered them as bounties.    I now have enough reputation points, but I would like it to be fixed, because I like offering bounties very much.  I would like system to check for my bounties when it checks if I can answer protected question. "grey" vs "gray" are both common equally in use? Yesterday I wrote "gray" in the meaning of the color, but my friend corrected me and told me to write "grey". Today I checked in the  and I found that they are both correct for the same meaning. So, now I just have doubt which one of them is more common in use. Could someone with experience in using these exercise typesetting packages please offer a quick compare and contrast of these packages to help me choose?  Packages under consideration are:         Having read briefly the documentation, they all seem to do the same thing generally, so could you please focus on the differences?  Some differences will not be obvious until I've learnt and used all the different packages but I want to better appreciate the differences now, a priori. Addition is to Integration as Multiplication is to ______ Insert a paragraph into a list that uses the whole text width Unable to locate package kubuntu-plasma5-desktop on 14.04 I am attempting to install kubuntu-plasma5-desktop on Kubuntu 14.04 amd64, following    sudo apt-add-repository ppa:neon/kf5 sudo apt update sudo apt install project-neon5-session project-neon5-utils project-neon5-konsole  sudo apt-add-repository ppa:kubuntu-ppa/next sudo apt-add-repository ppa:ci-train-ppa-service/landing-005 sudo apt update sudo apt install kubuntu-plasma5-desktop   Unable to locate package kubuntu-plasma5-desktop  How can I fix this error? Running macOS Sierra(Version 10.12.2 16C67).  I installed  version wine-1.8.6 (through a .pkg file). I opened up a game and it worked fine.  The next day when I downloaded Origin installer, it wouldn't open. When I double clicked on it, the Wine icon showed up in the dock and said it was open, but no windows showed up. When I clicked on another program(or on the desktop), Wine closed. Now when I try to start that same game I opened when I first installed Wine, the same thing happens that happened when I started Origin installer.  When I go to the terminal and type wine {path of .exe} I got this:   I installed wine tricks using brew install winetricks and it installed fine, yet it didn't change my situation.  winecfg works properly, and so does sh winetricks. So my friend has a USB flash drive that isn't working. I don't know a whole lot about "recovery" software so I figured I'd ask you guys.  What steps can I try (I have access to a Linux machine as well) to see....if I can get ANYTHING off the flash drive?  I've google'd around, but most of the stuff seems for windows. Solving a Diophantine equation with a large solution Change line spacing inside a node in TikZ how to stop firing oncomplete if save action has errors My requirement is to stop oncomplete call if save action has errors. I know I am doing some silly mistake.   Here I am unable to stop calling oncomplete function.  Requirement is, from VFP save method, data will get saved and then perform callout from oncomplete function. If there are any errors during save then stop making callouts.  Visualforce  &lt;apex:page id="hasErrorTestPage" controller="ErrorMessageFinder"  showHeader="false"&gt;     &lt;apex:pageMessages id="msgId"/&gt;     &lt;script&gt;         function performCallOutMethod()         {             var msg = document.getElementById('{!$Component.MSEForm.errorMsgInd}').value;             alert(msg);              if(msg == 'false' || typeof(msg) == 'undefined')             {                 alert('entering callout')                 performCallOut();                 return true;             }             else             {                 return false;             }         }     &lt;/script&gt;     &lt;apex:form id="MSEForm"&gt;         &lt;apex:actionFunction name="performCallOut" action="{!submit}" reRender="panelId,msgId"/&gt;          &lt;apex:outputPanel id="panelId"&gt;             &lt;apex:outputText value="{!hasError}" id="errorMsgInd"/&gt;         &lt;/apex:outputPanel&gt;         &lt;apex:inputText id="customerNm" value="{!CustomerName}"/&gt;&lt;br/&gt;         &lt;apex:commandButton value="Save" action="{!save}"                       oncomplete="return performCallOutMethod();" reRender="panelId,msgId"/&gt;     &lt;/apex:form&gt; &lt;/apex:page&gt;   Controller  public class ErrorMessageFinder {     public String CustomerName {get;set;}      public Boolean hasError {          get {              return ApexPages.hasMessages();          }            }      public PageReference save()     {            if(String.isBlank(CustomerName))         {             ApexPages.Message msg = new ApexPages.Message(ApexPages.Severity.Error, 'Name cannot be null');             ApexPages.addMessage(msg);             return null;         }         return null;      }       public PageReference submit()     {         try         {   //navigate to view page             PageReference pg = new PageReference('/'+ '0019000001UwnVS');             pg.setRedirect(true);             return pg;         }         catch (Exception ex)         {             System.debug('Error in submit ' + ex);             ApexPages.Message msg = new ApexPages.Message(ApexPages.Severity.Error, ex.getMessage());             ApexPages.addMessage(msg);              return null;         }     } }   Based on this code, if I hit save button without entering CustomerName then it is not showing error after save. It is showing error during oncomplete call and then navigating to view page, which I do not want.  Any help is appreciated. I have put a compiled code so that anyone can try with this code. Dropping the '-ing' in noun adjuncts I always remember many verbs ending in -ing.  Swimming club/cap and shaving foam for example. I now see increased use of swim club and shave foam.  Why has this happened, is it correct use of English ?