Relearning C++ for the sake of using OpenCL. I have created a Helper Class called CheckDevice which has a bunch of boiler plate code for getting device stats.   CheckDevice.h      class Utils     {     public:         Utils(){};         ~Utils(){};           template&lt;class T&gt;         static bool IsNull(T Object, char* name);      private:      };   CheckDevice.cpp      cl_command_queue Utils::CreateCommandQueue(cl_context context, cl_device_id *device)     {         cl_int err;         cl_device_id *devices;         cl_command_queue queue  = NULL;         size_t deviceBufferSize = -1;         cl_kernel kernel = 0;           Utils::IsNull&lt;cl_command_queue&gt;(queue, "Utils::CreateCommandQueue::queue");            return queue;     }   main.cpp      void main()     {          cl_kernel kernel            = 0;           Utils::IsNull&lt;cl_kernel&gt;(kernel, "clCreateKernel");      }   The question is when calling the function Utils::IsNull from within CheckDevice.cpp it works fine but when calling from main.cpp than I get the following in Visual Studios 2012     error LNK2019: unresolved external symbol "public: static bool __cdecl Utils::IsNull(struct _cl_kernel *,char *)" (??$IsNull@PAU_cl_kernel@@@Utils@@SA_NPAU_cl_kernel@@PAD@Z) referenced in function _main   1>C:\Users\Suri\Documents\Visual Studio 2012\Projects\HelloWorld\Debug\HelloWorld.exe : fatal error LNK1120: 1 unresolved externals   Any Help would be apperciated
When I write C++ code for a class using templates and split the code between a source (CPP) file and a header (H) file, I get a whole lot of "unresolved external symbol" errors when it comes to linking the final executible, despite the object file being correctly built and included in the linking.  What's happening here, and how can I fix it?
System Load Indicator only shows as a line unless hovered I installed the  GNOME extension on my Ubuntu 18.04, but for some reason, instead of showing a proper graph for CPU usage, it only shows a very thin line that seems to be a small portion of the actual graph. If I hover over it, the proper graph shows. How to make it show the whole graph all the time? my email limit is exceeded after sending 10-12 emails..what could be the problem..as i have seen the limit is 1000 emails/day.i am not able to find out what could be the problem..Can some give me some suggestions. As i also know we can send 10 emails in a single transaction.I am sending emails in a batch class.  I am calling this batch class on button click and filling emailList with emailsId's.                      String query='Select id from Lead';//No use of this query                     Batch_send_emails bse=new Batch_send_emails();                     bse.query=query;                                                         bse.resendEmails=emailList;                     database.executebatch(bse);           **Batch Class**           if(!resendEmails.isEmpty())           {               for(String s:resendEmails)                {                   emailsLeads.add(s);                }           }           Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();         mail.setToAddresses(emailsLeads);        // mail.setCcAddresses(ccAddresses);         String subject='GoToMeeting Invitation Details for '+subject;         String body='test';          mail.setHtmlBody(body);          mail.setSubject(subject);         Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });          } Is the notorious $n^2 + n + 41$ prime generator the last of its type? Proof Verification: Converse of Intermediate Value Theorem A function $f$ is increasing on $A$ if $f(x)\leq f(y)$ for all $x&lt;y$ in $A$. Show that the Intermediate Value Theorem does have a converse if we assume $f$ is increasing on $[a,b]$.  The converse of IVT along with the additional hypothesis would look like this: Lef $f:[a,b] \rightarrow \mathbb{R}$ be an increasing function on $[a,b]$ which satisfies: if $L$ is a real number such that $f(a)&lt;L&lt;f(b)$ (or $f(a)&gt;L&gt;f(b)$), then there exists a point $c\in (a,b)$ where $f(c)=L.$ If the preceding conditions are met, then $f$ is continuous on $[a,b]$.  The proof (if it's correct) I'm going to show is only for the $c \in (a,b)$, but I think for end points ($a$ or $b$), the method should be similar.  We want to show that given $c \in (a,b)$, for all $\epsilon&gt;0$, there exists a $\delta&gt;0$ such that $|x-c|&lt;\delta \implies |f(x)-f(c)|&lt;\epsilon$.  Since $f$ is increasing, we know that $f(a)\leq f(c)$. If $f(c)-\epsilon&lt;f(a)$, then set $x_1=a$, if $f(c)-\epsilon\geq f(a)$, then we know by hypothesis that a $x_1&lt;c$ exists such that $f(x_1)=f(c)-\epsilon.$ In either case, we have for $x \in (x_1,c]$ $$ f(c)-\epsilon \leq f(x_1) \leq f(x) \leq f(c) .$$  In a similar way, since we know that $f(c)\leq f(b)$, we can deduce that a $x_2&gt;c$ exists such that, for $x \in [c,x_2)$ $$f(c)\leq f(x)\leq f(x_2)\leq f(c)+\epsilon .$$  Pick $\delta = \min \{c-x_1,x_2-c \}$, we then have $$|x-c|&lt;\delta \implies |f(x)-f(c)|&lt;\epsilon .$$  Is this correct? In the proof that I saw, they originally used $\frac{\epsilon}{2}$, instead of just $\epsilon$, but I think this one works just as well, what do you guys think? Can you transfer a Windows 7 XP-mode VHD to a new PC without the need for reactivation? I told my wolves to sit down and I accidentally forgot to tell them to stand up and I left them. Now I cannot find them, how do you get back to your wolves if they are lost? Custom environment in wrapfigure Does wind raise air temperature? In my undergrad physics classes, temperature was described as "the average kinetic energy of molecules".  By simple, and probably naive, logic, one could then conclude that wind, which is basically just moving air, would raise the temperature of the air.  However, this seems too simple to be true.  Does wind actually slightly raise air temperature?  I can see a couple potential arguments against this idea:   It could be the case that the macroscopic wind and the microscopic kinetic energy of the air molecules don't really "interact", for lack of a better word. It could be the case that the macroscopic and the microscopic motions do "interact", but since the macroscopic wind is on such a large scale compared to the average kinetic energy of individual molecules, any system in which we use the average kinetic energy of the molecules is so small that the wind is effectively constant, and so it could be ignored. Regardless, I'm guessing that the temperature only depends on the relative motion of the air molecules, so the wind just isn't even relevant   Can anybody provide some more educated input? How to add subject alernative name to ssl certs? Prove that the polynomial $(x-1)(x-2)\cdots(x-n) + 1$, $ n\ge1 $, $ n\ne4 $ is irreducible over $\mathbb Z$ I try to solve this problem. I seems to come close to the end but I can't get the conclusion. Can someone help me complete my proof. Thanks          Show that the polynomial $h(x) = (x-1)(x-2)\cdots(x-n) + 1$ is irreducible over $\mathbb Z$ for all $n\ge1$ and $ n\ne4$.      Suppose $h(x) = f(x) g(x)$, then we must have $f(i)g(i) = 1$ for all $i = 1,2,...n$. So both $f(i)$ and $g(i)$ are $1$ or $-1$. In either case, $m(x) = f(x) - g(x)$ has degree smaller than $n$ and have $n$ different roots ($1,2,...,n$). So we must have $m(x) = 0$. Then $h(x) = f(x)^{2}$. So $n$ must be even. Let $n = 2k$. Because $f(x)$ has degree $k$, there are $k$ values from $\{1,2,...,2k\}$ at which $f(x)$ is $1$ and $k$ values at which $f(x)$ is $-1$.  This is where I got stuck. Hope some one can help me solve this. Thanks. How do I find out which version and derivative of Ubuntu is right for my hardware in terms of minimal system requirements? For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements? I love recursion. I think it simplifies things a lot. Another may disagree; I think it also makes the code a lot easier to read. However, I've noticed that recursion is not used as much in languages such C# as they are in LISP (which by the way is my favorite language because of the recursion).   Does anybody know if there is any good reasons not use recursion in the languages such as C#? Is it more expensive than iteration? Is the Macbook 12 inch's USB-C charger interchangeable with other USB-C chargers or devices? If there is only the Macbook 12 inch USB-C charger nearby, can it be used to charge other USB-C devices, such as any Android phones that also use USB-C? (will it be "too powerful" and damage other devices?)  Vice versa, if there is a Quick Charge 2.0 or 3.0 USB-C charger from other devices nearby, can it be used to charge the Macbook 12 inch?  The main concern is about whether it could damage the device or battery. Why *not* parse `ls` (and what to do instead)? How can I bind the meta key (a.k.a.  / Windows key) to a left click? Hitting the meta key should trigger a left click, and pressing down on it should allow me to drag and drop (just like it would do when holding down left click).  I tried using System Preferences -> Shortcuts and Gestures:    but I cannot set "meta" alone as being a shortcut.  I use Kubuntu 14.10 Plasma 4 and Kubuntu 14.04 LTS x64.   (On Windows 7 SP1 x64 Ultimate I can achieve that using the program .) How can I '\input' a file without getting the implicit newline? Polynomial in $n$ variables Resizing an iframe based on content I am working on an iGoogle-like application. Content from other applications (on other domains) is shown using iframes.   How do I resize the iframes to fit the height of the iframes' content?  I've tried to decipher the javascript Google uses but it's obfuscated, and searching the web has been fruitless so far.  Update: Please note that content is loaded from other domains, so the  applies. Getting coordinates by clicking on QGIS Canvas with PyQGIS? Are there any procedures when working with QgsMapCanvas (pyqgis, qgis) in order to obtain a pair of coordinates by clicking on the map canvas?   Are there any sample Python codes that demonstrate this? Prove $3(x^2y+y^2z+z^2x)(xy^2+yz^2+zx^2)\ge xyz(x+y+z)^3$ if $x,y,z$ are positive real numbers,Prove:$$3(x^2y+y^2z+z^2x)(xy^2+yz^2+zx^2)\ge xyz(x+y+z)^3$$ Additional info:$\sum_{cyc}$ denotes sums over cyclic permutations of the symbols $x,y,z$. I'm looking for solutions and hint that using Cauchy-Schwarz and AM-GM because I have background in them.  Things I have done: Writing Left hand side in expanded form:$$LHS=3(\sum_{cyc}x^3y^3+\sum_{cyc}xy^4z+3x^2y^2z^2)$$ Right now I don't have good idea were to start(Is expanding and looking for AM-GM is good?).So any hint is appreciated. Source : This inequality can be found as Problem 42, page 13, in the book &quot;Old and New inequalities&quot; by Titu Andreescu, where it is attributed to Manlio Marangelli.