I have a interface for element that returns the mesh for the current element. I have mesh which is collection of element. The mesh also has reference to mesh because it want to manipulate mesh. When ever I try to compile I get error saying invalid use of incomplete type ‘class Mesh’.  AbsElem.h  class Mesh;  class AbsElem{   virtual Mesh& GetMesh()const = 0; };   Elem1.h  #include "AbsElem.h" #include <vector>  class Elem1 : public AbsElem{    Elem1(Mesh& m):my_mesh(m){}   virtual Mesh& GetMesh() const{return my_mesh;}    void DoStuff(){    my_mesh.GetVal();   }    Mesh& my_mesh; };   Mesh.h  #include "Elem1.h"  class Mesh{   public:    int GetVal(){return 1;}   private:   std::vector<Elem1> collect_elem_; };   main.cpp  #include "Mesh.h"  int main(){   Mesh m; }   compile by : g++ main.cpp  compilation error :       In file included from Mesh.h:1,                    from main.cpp:1: Elem1.h: In member function ‘void Elem1::DoStuff()’: Elem1.h:10:4: error: invalid use of incomplete type   ‘class Mesh’       my_mesh.GetVal();       ^~~~~~~ In file included from Elem1.h:1,                    from Mesh.h:1,                    from main.cpp:1: AbsElem.h:2:7: note: forward declaration of ‘class Mesh’  class Mesh;          ^~~~

I often find myself in a situation where I am facing multiple compilation/linker errors in a C++ project due to some bad design decisions (made by someone else :) ) which lead to circular dependencies between C++ classes in different header files (can happen also in the same file). But fortunately(?) this doesn't happen often enough for me to remember the solution to this problem for the next time it happens again.  So for the purposes of easy recall in the future I am going to post a representative problem and a solution along with it. Better solutions are of-course welcome.     A.h  class B; class A {     int _val;     B *_b; public:      A(int val)         :_val(val)     {     }      void SetB(B *b)     {         _b = b;         _b->Print(); // COMPILER ERROR: C2027: use of undefined type 'B'     }      void Print()     {         cout<<"Type:A val="<<_val<<endl;     } };       B.h  #include "A.h" class B {     double _val;     A* _a; public:      B(double val)         :_val(val)     {     }      void SetA(A *a)     {         _a = a;         _a->Print();     }      void Print()     {         cout<<"Type:B val="<<_val<<endl;     } };       main.cpp  #include "B.h" #include <iostream>  int main(int argc, char* argv[]) {     A a(10);     B b(3.14);     a.Print();     a.SetB(&b);     b.Print();     b.SetA(&a);     return 0; }


Google Search Console's "Core Web Vitals" is showing these two graphs.  Notice that the number of "good" URLs in one graph exactly match the number of "bad" URLs in the other. Each day always has the same number on each graph, so it's not likely a random coincidence.  The reports provide only one example, and it is the same URL in both cases (). The page is static, with no scripts or forms.  The site has hundreds of other pages (all also static without forms), so what is so special about these reported pages that every one of them would be good in one context and bad in the other?

Google Search Console is saying:  CLS issue: more than 0.25 (desktop) First detected: 5/27/20 Status: Poor   But the  is simply a table containing UTF-8 text. It has an external style sheet, but no images, scripts, or forms. The one possibly uncommon thing is that I serve it as XHTML. Why would this page experience shift? Strangely, the complaint occurs only for desktop, not for mobile, even though it is a wide table that can be read much better on a large screen. (Note that I'm not especially concerned about performance, etc. itself; the page is mostly only for my own use.  I'm simply curious about how and why layout shift could be detected.) UPDATE: I've found a related problem, which I've posted as


I want to subtract n days from the current date in Java.  How do I do that?

Anyone know a simple way using Java calendar to subtract X days from a date?  I have not been able to find any function which allows me to directly subtract X days from a date in Java. Can someone point me to the right direction?


I've tried my hand at making fried rice a few times now. I seem to be getting these things wrong:   Texture of rice Browning of rice   I've been cooking the rice, stir frying some veggies, and an egg in a separate pan. Add rice and egg to veggies, stir fry a couple minutes, eat. How can I improve this?

I see a lot of recipes for fried rice, but never seem to be able to give the gorgeous lightly browned color (and therefore flavor) to my rice.   This is before adding soy sauce or anything else. Is this a question of heat, or quantity of oil? How do they do it in the restaurant (e.g. young chow fried rice)?


I've a bootable USB with Debian. Normally I clone the disk with dd, write the image on a new USB disk, mount this disk on my filesystem and edit some files. Is it possible to edit files on the image without writing the image to USB and mount the USB? I've tried ISO Master, but that raises an error: Failed to read volume info: 'Failed to read expected number of bytes'.

I ran these commands:  VBoxManage clonehd d6b9f0a5-98df-48ca-83c8-91a0809ec349 --format RAW Debian.raw sudo dd if=~/.VirtualBox/HardDisks/Debian.raw of=/dev/sda5   When I try to mount the partition, I get this complaint:  EXT4-fs (sda5): VFS: Can't find ext4 filesystem   Now I know that the VM had an ext4 partition. What did I do wrong?


Please see the following JavaScript code:  var cis_current_time = 0;  setInterval(function() {     cis_current_time += 1; },1);  $("#timingInfo").html(cis_current_time); setTimeout(function() {     $("#timingInfo").html($("#timingInfo").html() + ', ' + cis_current_time); },1000);   As a result I except to get 0, 1000, but it returns 0, number near 200  Please check a   What is the reason of such behavior?

Something that has always bugged me is how unpredictable the setTimeout() method in Javascript is.  In my experience, the timer is horribly inaccurate in a lot of situations. By inaccurate, I mean the actual delay time seems to vary by 250-500ms more or less. Although this isn't a huge amount of time, when using it to hide/show UI elements the time can be visibly noticeable.  Are there any tricks that can be done to ensure that setTimeout() performs accurately (without resorting to an external API) or is this a lost cause?


I have problem with wide grids of type TStringGrid. If user scrolls grid to the right and selects row then grid automatically scrolls left so first column can be seen, but not the column user is interested in. How to prevent such scrolling?  I use TurboDelphi (Delphi 2006).  My grid has standard options with changes:   goColSizing=True  goRowSelect=True

I have a DBGrid on a form.  The DBGrid has many columns, so an horizontal scroller is displayed.  I scroll the DBGrid view to the right to see more columns.  If I select a row, the DBGrid view is automatically reset to view the first column (As if I scroll back to the left most position).     Is there a way to prevent that?


I'm trying to show that if $R$ is an Artinian ring, then for finitely generated modules $M,N,N'$, we have that $M\oplus N\cong M\oplus N'$ implies that $N\cong N'$.   I'm supposed to do this by decomposing $M,N,N'$ and then using the Krull-Schmidt Theorem.  For the first part, this means writing $M,N,N'$ as direct sums of non-zero submodules. As $R$ is Artinian, finitely generated modules are of finite length (from Hopkins' Theorem) and hence these decompositions will be of finite length. Therefore, we can use the Krull-Schmidt Theorem, which says that these indecomposable components are uniquely determined up to isomorphism.  However, this only gives us information about the components of the decompositions of these modules - not about the relations between them (specifically, between $N$ and $N'$).   How can I use the Krull-Schmidt Theorem to get the desired result?

Usually for modules $M_1,M_2,N$ $$M_1 \times N \cong M_2 \times N \Rightarrow M_1 \cong M_2$$ is wrong. I'm just curious, but are there any cases or additional conditions where it gets true?  James B.


I am looking to hire a co-signer online for a loan that’s been approved pending co-signer approval. I completely comprehend that my financial assessment is sketchy however I would like to offer some clarifications as to why Things adversely affected my credit score and see if anyone would be willing to share in the loan. Is there any such service ? And does it work?

I am a foreigner to USA and would like to pursue masters in CS in USA. But based on the current state of USD, I won't be able to pay the costs of tuition on my own. So, I will be taking a loan from international student loan lenders.  The thing is, they mostly require US citizen or US PR cosigners, which I don't know any. I have found online that there are websites which offer to find a cosigner for people who have bad credit scores or can't find anyone to cosign their agreements.    I am very sceptical about their services, and mostly think that they are scam, but I don't have much choice left to find a cosigner elsewhere. Just wanted to ask, have you ever heard of these services, and do you believe they are real ?  (Sorry if this is out of context, this is my first question here.)


I would like to get a laptop, mainly to use in school and extracurriculars. While I can save up with my job, it would be much easier to finance the laptop instead, since I'm saving up for other things as well. At 15, is it possible for me to finance the laptop, or anything else for that matter? I would assume not, for legal reasons, but am asking just to be sure. Thank you!

I'm currently 16 and have been invited to attend a National Youth Conference for National Security in Washington DC this upcoming fall. I just moved in with my mom and this trip isn't exactly ideal for us financially. My mom said I was more than welcome to go on the trip as long as I came up with the money. I could make the money over the summer but the enrollment deadline is June 24. I've made a Go Fund Me page but I don't think that will help in time. I'm not sure how old I must be to take out a loan or anything about the process. Any help/advice is appreciated in this situation


I have this function:  final ArrayList<Addressable> tempStoreList = new ArrayList<>(); tempStoreList.addAll(addressables);      Collections.sort(tempStoreList, new Comparator<Addressable>() {         @Override         public int compare(Addressable o1, Addressable o2) {              double distanceToO1 = 0;             double distanceToO2 = 0;              if (o1.getAddress() == null) {                 return (o2.getAddress() == null) ? 0 : -1;             }             if (o2.getAddress() == null) {                 return 0;             }              if (userLocation != null && o1.getAddress() != null && o2.getAddress() != null) {                 distanceToO1 = GlobalUtilities.distance(userLocation, o1.getAddress().getLocation(), "K");                 distanceToO2 = GlobalUtilities.distance(userLocation, o2.getAddress().getLocation(), "K");             }              if (distanceToO1 < distanceToO2) {                 return -1;             } else if (distanceToO1 > distanceToO2) {                 return 1;             } else {                 return 0;             }          }     });   For some reason, I keep getting a NPE on:  if (o2.getAddress() == null) {     return 0; }   Which to me means that null was somehow placed in the array. Anyone ever encounter this before?

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


My worked example sheet states     Prove $\mathbb{Z}[i]/(2- i) \cong \mathbb{Z_5}$ using the following steps:      Let $G = \mathbb{Z}[i]/(2- i)$         $G = \{ \bar{x} + \bar{y}\bar{i} \mid x,y \in \mathbb{Z} \}$   $G = \{ \bar{x} \mid x \in \mathbb{Z} \}$, because $\bar{2} = \bar{i}$   Show that $G = \{ \bar{0},\ldots,\bar{4}\}$   Finally, prove $G \cong \mathbb{Z_5}$      The proof is clear to me but I do not know how to rigorously show $G = \{ \bar{x} + \bar{y}\bar{i} \mid x,y \in \mathbb{Z} \}$ and $G = \{ \bar{0},\ldots,\bar{4}\}$.  For the first one, I think this is just the definition of a quotient ring but is that enough for rigour? While for the second one, we have the relation $\bar{5} = \bar{0}$ in $R$ but how can I show ( rather write ) $G$ has the mentioned elements.   I guess, I am asking for a formal way of writing this.   PS: The proof for similar problem is available on the forum, but my problem is how much detail is enough. ( For me the context is an examination. ) Pardon my elementary question.

I am trying to prove that $\mathbb Z[i]/ \langle 1+2i \rangle$ is isomorphic to  $\mathbb  Z_5$.   The only thing that came to my mind was trying to apply the first isomorphism theorem using an appropiate function. If I consider the euclidean function $N: Z[i] \setminus \{0 \}  \to  \mathbb N$ defined as $N(a+bi)=a^2+b^2$, then I can express any element $z$ in $\mathbb Z[i]$ as $z=(1+2i)q+r$ with $N(r)=1,2,3,4$ or $r=0$.   If I define $f:\mathbb Z[i] \to \mathbb  Z_5$ as $f(x=(1+2i)q_x+r_x)=\overline{r_x}$, then it is clear that $f(x)=0$ if and only if $x \in  \langle 1+2i \rangle$. The problem with this function is that it doesn't satisfy $f(x+y)=f(x)+f(y)$ and it is not surjective for if $r_x=f(x)=3 (5)$, then if $r_x=a+bi$, we have $a^2+b^2=3$, which is absurd.  I don't know what else to do, any suggestions would be appreciated.


I have created a C# command line application that creates a few reports automatically for my client.  However, even though they use 95% of the same code I would like to split them in to different processes. I am using Windows task scheduler to run them.  How do I set up the C# application to accept Command line parameters upon runtime?  I cannot find any explanation of this on the internet.

When building console applications that take parameters, you can use the arguments passed to Main(string[] args).   In the past I've simply indexed/looped that array and done a few regular expressions to extract the values. However, when the commands get more complicated, the parsing can get pretty ugly.    So I'm interested in:   Libraries that you use Patterns that you use   Assume the commands always adhere to common standards such as .


What's the best way to measure the resistance and inductance of a coil at a given frequency? I need these parameters for my LTSpice-Simulation which assumes an RL series circuit.  The coil has 8 windings and is printed on a PCB. The eDesignSuite from STMicroelectronics estimates an inductance of 1.72µH. DC-resistance is approx. 1.27Ohm (measured).  Will the resistance at 13.56MHz be equal to the DC-resistance? (How can I verify this?) How can I verify the inductance of the coil at approx. 13.56MHz?  Thanks!

I have been looking the number of methods to measure inductance of a coil if you don't have an LCR meter available, and I have had some difficulty. I designed and built a coil and I would like to confirm its inductance, which theoretically is ~\$2\mu\mathrm{H}\$.  One method is putting a resistor in series with the inductor and applying a signal. I've seen two things in regards to this one is to adjust the input frequency so that the voltage across the resistor is half the input and then work out \$L\$ using         – Schematic created using  $$ L = \frac{R}{2\pi f\sqrt{3}} $$ And the other is to instead adjust the input frequency until the signals are \$-45^\circ\$ (degrees) out of phase and then work out \$L\$ using $$ L = \frac{R}{2\pi f} $$ I've tried both these on a inductor of known value and I do not get close to the expected value. So I figure I am doing something wrong, but I am not sure what as it is a pretty simple setup. More importantly, I do not fully understand the formulas used and how one gets to these to work out the inductance.  The known inductor is \$\sim 1.5 \mu\mathrm{H}\$ (tolerance 20%) and the resistor I used was \$6.75 \mathrm{k}\Omega\$. So I also wonder if perhaps the inductor value is too low for this type of setup for measurement as I have typically seen \$\mathrm{mH}\$ in the results of the examples I have seen? Or if I choose an inappropriately valued resistor?  I then tried the LC trap, with \$10 \mathrm{nF}\$ capacitor and my inductor, and that worked for me. Pulsing the input signal and then looking at ripple frequency.  $$ f = {1\over 2\pi\sqrt{LC}} $$ At least it appears to have as I was able to work out the inductance of the known inductor to within its tolerance. And got near to what I expected with my built coil.          Mostly I am curious about the first methods using the series resistor, as this is one of the first things that comes up when looking at how to measure inductance, And I would like to understand this better and get it to work for me if possible.


Problem : Evaluate $ \int \cfrac { \sec^2x}{ ( \sec x +  \tan x)^{9/2}}dx $      Solution :   $ \int \cfrac { \sec^2x}{ ( \sec x +  \tan x)^{9/2}}dx $      $ \int \cfrac { \sec^2x}{ \left(1+ \sin x \over \cos x \right)^ {9/2}}dx $      $ \int \cfrac { \sec^2x}{ (\sin {x \over 2} + \cos {x \over 2})^9 \over (\cos^2 {x \over 2} - \sin^2 {x \over 2})^ {9/2}}dx $      $ \int \cfrac { \sec^2x}{ \left(\cos {x \over 2} + \sin {x \over 2} \over\cos {x \over 2} - \sin {x \over 2}\right)^ {9/2}}dx $      $ \int \cfrac { \sec^2x}{ \left(1 + \tan {x \over 2} \over 1 - \tan {x \over 2}\right)^ {9/2}}dx $      $ \int \cfrac { \sec^2x}{[tan({ \pi \over 4}+ { x \over 2})]^  {9/2}}dx $   Am I doing right ?

I am unable to solve the following integral: $$\int \frac{\sec^{2}{x}}{(\sec{x} + \tan{x})^{5/2}} \ \mathrm dx.$$   Tried putting $t=\tan{x}$ so that numerator has $\sec^{2}{x}$ but that doesn't help.


While my question applies to Jenkins (software) which was named after Jenkins named meant to evoke a feel of English butler, there is a historical precent:    Wikipedia article has Jenkins' in the title and Jenkins's in reference to historical book.  However modern grammar rules seem to imply that correct possessive form in modern English would be Jenkins'es.  So what is correct? Or are several options acceptable?

According to my grammar book, but at variance to the answer to , the correct singular possessive if a word ends in ‑s is:     James’s car   The grammar book allows exceptions for historical nouns, so the examples in the answer to the above-linked question would pass muster.  However, I’m sure that I learnt at school (which, admittedly, was a while ago) that for a singular (proper) noun ending in ‑s, the apostrophe went after the s and there was no additional s.  I don’t wish to start a flame war on which is correct, though my question doesn't really make sense if my grammar book is wrong!  What I’m curious about is when the change occurred.  :  So my question is when did James’s become the correct form and James’ the incorrect one?


Suppose the sun would turn into a black hole. Now neglecting the effect on the living beings on the earth. would the sun suck up the earth or the earth's revolution would not be affected?

I am interested in theoretical and practical considerations.


I'd spent much time for this but didn't get any results.. Could u give me only the idea but not a full proof

Suppose $k$ is a field that is finitely generated as a ${\mathbb Z}$-algebra.  (That is, $k$ is a quotient of ${\mathbb Z}[X_1,\dots,X_n]$ for some $n$). Does it follow that $k$ is finite?


I'm new to C++. I'm trying to create a utility function to execute commands on the commandline from the application. There are multiple places where it will be called from so I wanted to abstract it out. This is how the method looks like. std::string ExecuteCommand(const string& arguments) const {     ipstream iStream;     auto childProcess = child(cmd, std_out > iStream);     string response;     string line;      while (getline(iStream, line) && !line.empty())     {         response += line;     }      childProcess.wait();      auto exitCode = childProcess.exit_code();      return response; }  I'm interested in the response from running the command as well as the exit code. I'm thinking of the following: From the caller string cmd = "dir" // For simplicity sake int exitCode = -1; string response = ExecuteCommand(cmd, exitCode);  Change to method signature: std::string ExecuteCommand(const string& arguments, &exitCode)  Will something like work? Also, is it possible to not initiate the exitCode and just get the return value from the method? Looking forward to your responses. Thanks!

Is there a preferred way to return multiple values from a C++ function?  For example, imagine a function that divides two integers and returns both the quotient and the remainder.  One way I commonly see is to use reference parameters:  void divide(int dividend, int divisor, int& quotient, int& remainder);   A variation is to return one value and pass the other through a reference parameter:  int divide(int dividend, int divisor, int& remainder);   Another way would be to declare a struct to contain all of the results and return that:  struct divide_result {     int quotient;     int remainder; };  divide_result divide(int dividend, int divisor);   Is one of these ways generally preferred, or are there other suggestions?  Edit: In the real-world code, there may be more than two results.  They may also be of different types.


$A$ is a square matrix of order $n$. Show that $\det(cA)=c^n\det(A)$, $c\in\mathbb{R}$.  I don't know where to begin. Can anyone offer some guidance?

Let $A$ be an $n \times n$ matrix and $k$ be a scalar. Prove that $\det(kA)=k^n\det A$.   I really don't know where to start. Can someone give me a hint for this proof?


I noticed a rash of couples recently who will announce to friends and family, "We're pregnant!" At first I thought this was just a cutesy way of announcing a pregnancy that was intended to be humorous, with the joke being that one partner was somewhat less pregnant than the other. But since first noticing it a few years ago, I've heard and seen it in print much more often.  Here's an example of an image that appears to use it in a humorous context:     Contrast with this image, which seems to be entirely serious:     Is this an acceptable use of the word 'pregnant'? And if so, how far back does the usage go?

According to Collins English Dictionary, and of course as everyone knows, a  is     a woman who is trained to provide support to women and their families during pregnancy, childbirth, and the period of time following the birth   However, the definition in  says:     A support person, usually female, who may not have medical or midwifery training, who provides emotional assistance to a mother or pregnant couple before, during or after childbirth.   Is pregnant couple actually an acceptable term for referring to an expectant couple?


I will click featured or something else and it automatically redirects me to updates it is making me mad someone please help me out thanks I appreciate it

I will click featured or something else and it automatically redirects me to updates.   What sequence of things can I try to unstick this or reset the application so I can browse the features and other sections of the Mac App Store?


I have seen traces like this enough times to begin wondering if there is a purpose and benefit. The only technical explanation I can come up with is that perhaps these curved traces increase the inductance between the end-points (for the type shown on the right of the IC) and decreases capacitive coupling for the type shown at the bottom. If this is the case, why would that be desirable? If not, what is the purpose? Also, I thought it was generally back practice to include sharp edges in the traces.     This particular screencapture is taken from the PCB of the new

On some PCB designs, specific traces are routed in curious ways. This probably has to do with high frequency design considerations and general signal behavior that I am not familiar with.  Let's take this PCB (somewhere from the web) as an example. It shows part of a PCIe card with SATA routing and DDR2 RAM:    I highlighted 4 areas that qualify as unusual trace layout (from my perspective).   What are those shapes supposed to achieve? How do designers come up with what pattern is required? Another example of wave shaped, antenna like routing. This is fairly rare. But obviously the designer deliberately avoided 45° traces. Why? Curves again and a single "pulse" within the trace. How can this have any significant effect?   So what are the use cases and benefits of this techniques?   I want to be able to take those into consideration when doing future PCB designs.


I'm getting a NullPointerException while making a ListView using a custom adapter and don't know the part of code causing the error. Following is the code snippet:  ChatMessageAdapter.java  package com.myappcompany.rajan.thefictionalchat;  import android.content.Context; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import android.widget.TextView;  import java.util.ArrayList;  public class ChatMessageAdapter extends ArrayAdapter<ChatText> {      ChatMessageAdapter(Context context, ArrayList<ChatText> list) {         super(context, 0, list);     }      @NonNull     @Override     public View getView(int position, View convertView, ViewGroup parent) {          View currentView = convertView;         if(currentView==null) {             LayoutInflater.from(getContext()).inflate(R.layout.list_items, parent, false);         }         ChatText chatText = getItem(position);          TextView textView;         textView = (TextView)currentView.findViewById(R.id.chat_text);         textView.setText(chatText.getMessage());          if(chatText.getMessageType().equals("PERSON_1")) {             textView.setGravity(Gravity.LEFT);         }         else if(chatText.getMessageType().equals("PERSON_2")) {             textView.setGravity(Gravity.RIGHT);         }         else {             textView.setGravity(Gravity.CENTER_HORIZONTAL);         }          return currentView;     } }    list_items.xml  <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:tools="http://schemas.android.com/tools"     android:orientation="vertical"     android:layout_width="match_parent"     android:layout_height="wrap_content"     >      <TextView         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:id="@+id/chat_text"         tools:text="Hello" />  </LinearLayout>   I'm getting the following run-time error from the log as the app crashes:  java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)' on a null object reference         at com.myappcompany.rajan.thefictionalchat.ChatMessageAdapter.getView(ChatMessageAdapter.java:32)

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


In a context of quantum mechanics, why does:  $$ \langle x | p \rangle = \left(\frac{1}{2\pi\hbar}\right)^{3/2} e^{ipx/\hbar} $$  Is there any proof for this?

What would be the proof for $\langle q| p \rangle = e^{ipq}$?  Is it derived from canonical commutation relation?  ($|q \rangle $ represents the position eigenstate, while $|p \rangle$ represents the momentum eigenstate.)


Hey guys so i'm writing a program that i want to make faster by adding multiple threads   what it does it reads from a richtextbox and parse it to the end of a website then grabs data and if it contains certain string then it adds it to another textbox  Imports System.Net Imports System.IO Public Class Form2 Dim i As Integer Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click     i = RichTextBox1.Lines.Count     StartThreads() End Sub  Private Sub StartThreads()     Dim count As Integer     For count = 0 To TextBox1.Text         Dim thread = New Threading.Thread(AddressOf Chk)         thread.IsBackground = True         thread.Start()         Threading.Thread.Sleep(500)     Next End Sub   Private Sub Chk()     While i > 0         i = i - 1         Threading.Thread.Sleep(500)         Application.DoEvents()         Dim text As String = RichTextBox1.Lines(i).ToString         Dim request As WebRequest = WebRequest.Create("WWW.WEBSITE.COM" + text)         Dim responce As HttpWebResponse = CType(request.GetResponse(), HttpWebResponse)         Dim datastream As Stream = responce.GetResponseStream         Dim reader As New StreamReader(datastream)         Dim strData As String = reader.ReadToEnd         Application.DoEvents()         If strData.Contains("no-result") Then             Application.DoEvents()         Else             Application.DoEvents()             RichTextBox2.AppendText(Environment.NewLine & text)         End If     End While End Sub End Class   I get an Error for Cross Thread operations not valid and i tried reading up on delegates and i get how they work in a basic way but i don't think that will solve my main issue of reading a textbox at the same time while doing the same operation with different values and pasting it to the same (other) textbo also seems like even when i use the nonprofessional way and turn the cross thread check off i  get duplicate results which i don't know why either

I have a scenario. (Windows Forms, C#, .NET)   There is a main form which hosts some user control. The user control does some heavy data operation, such that if I directly call the UserControl_Load method the UI become nonresponsive for the duration for load method execution. To overcome this I load data on different thread (trying to change existing code as little as I can)   I used a background worker thread which will be loading the data and when done will notify the application that it has done its work.   Now came a real problem. All the UI (main form and its child usercontrols) was created on the primary main thread. In the LOAD method of the usercontrol I'm fetching data based on the values of some control (like textbox) on userControl.    The pseudocode would look like this:  CODE 1  UserContrl1_LoadDataMethod() {     if (textbox1.text == "MyName") // This gives exception     {         //Load data corresponding to "MyName".         //Populate a globale variable List<string> which will be binded to grid at some later stage.     } }   The Exception it gave was     Cross-thread operation not valid: Control accessed from a thread other than the thread it was created on.   To know more about this I did some googling and a suggestion came up like using the following code  CODE 2  UserContrl1_LoadDataMethod() {     if (InvokeRequired) // Line #1     {         this.Invoke(new MethodInvoker(UserContrl1_LoadDataMethod));         return;     }      if (textbox1.text == "MyName") // Now it wont give an exception     {     //Load data correspondin to "MyName"         //Populate a globale variable List<string> which will be binded to grid at some later stage     } }   BUT BUT BUT... it seems I'm back to square one. The Application again  become nonresponsive. It seems to be due to the execution of line #1 if condition. The loading task is again done by the parent thread and not the third that I spawned.  I don't know whether I perceived this right or wrong. I'm new to threading.  How do I resolve this and also what is the effect of execution of Line#1 if block?  The situation is this: I want to load data into a global variable based on the value of a control. I don't want to change the value of a control from the child thread. I'm not going to do it ever from a child thread.   So only accessing the value so that the corresponding data can be fetched from the database.


The Teleportation Circle spell (PHB pg. 282) states that in order for the spellcaster to "target" a remote teleportation circle he or she must know that remote circle's unique sigil sequence.  What if a player or party wants to use a permanent teleportation circle to teleport to another permanent circle?  This use case is not covered - or am I missing it? I am including permanent teleportation circles in my campaign as sort of a municipal service "if you can afford or justify it" to get from one city to the next (and it won't always be safe, no). I have some ideas about how to set it up (as in how to have a "local spellcaster" set a destination for the portal) but I am curious if there is a method already defined elsewhere.

The 5th-level spell  says:     As you cast the spell, you draw a 10-foot-diameter circle on the ground inscribed with sigils that link your location to a permanent teleportation circle of your choice, whose sigil sequence you know and that is on the same plane of existence as you. A shimmering portal opens within the circle you drew and remains open until the end of your next turn.      [...]      You can create a permanent teleportation circle by casting this spell in the same location every day for one year. You need not use the circle to teleport when you cast the spell in this way.   The teleportation circle you draw seems to be a point of departure only when you cast it. When it's a permanent teleportation circle, however, it doesn't mention whether you can use it as a point of departure.  Can permanent teleportation circles only serve as destinations?


From , page 8. It seems like \setchemfig is not defined:  \documentclass{article} \usepackage[T1]{fontenc} \usepackage{textcomp} \usepackage[italian]{babel} \usepackage{chemfig}  \begin{document}     \setchemfig{atom sep=50pt}     \chemfig{A-B} \end{document}   ! Undefined control sequence. l.9 \setchemfig {atom sep=50pt} The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., `\hobx'), type `I' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined.   Client: Texmaker 4.5 Compiler: XeLaTeX

I'm trying to compile a document that only works with an up-to-date distribution, so I'd like to know: how do I update my distribution? Please provide screenshots where appropriate.  List of answers           To keep an eye on what’s going on at CTAN you may subscribe to the  or the RSS feed feed://www.mail-archive.com/ctan-ann@dante.de/maillist.xml


I set up hlatex (the package for compiling in Korean) but when I build the file, I end up getting ?? instead of 안녕. How do you fix this?  MWE:  \documentclass{article} \usepackage{hangul} \begin{document} testing 안녕 \end{document}   No errors come up. The word "testing" comes up, but "안녕" does not.

I've been unable to find a concise answer anywhere else on the web. Since its only a few words, albeit crucial ones, that are in Korean I don't want to have to muck around with HLaTex or deviate from pdfLaTeX that I'm using at the moment.


We know that if a sum is convergent, but it's not convergent absolutely, then we can arrange it's terms so that it converges to any real number.  For complex numbers similar theorem does not hold i. e. if a sum is convergent  and not convergent absolutely, then it can happen so that we can't obtain every complex number (which is pretty obvious because for example we can't obtain non-real complex numbers from a sum of real numbers). However there exist sums that have this property, for example $\sum \frac{i^n}{n}$.  My question is, what are the criteria for which a complex sum that converges but doesn't converge absolutely can be rearranged so that it converges to any number on the complex plane.  Question source is my own curiosity. By criteria I mean any sort of necessary or sufficient condition, within reason of course.

The Riemann rearrangement theorem states that if $\sum\limits_{n=0} ^{+ \infty} a_n$ is conditionally convergent and $M \in \mathbb{R}$ then there exists a permutation $ \sigma (n) $ such that $\sum\limits_{n=0}^{+ \infty} a_{\sigma(n)} \ =M$.  Could you tell me how to use this to prove a more general statement?  That if we have $\sum\limits_{n=0} ^{+ \infty} c_n$ - conditionally convergent series of complex numbers, then there exists a line $l$ on the plane such that each point of this line can be a limit of the series.  I'd appreciate any help.


I'm told to show that $2^n < n!$ using induction  This is my attempt at it:  BC: $n=4, 2^4 = 16 < 4!$  IH: n = k, $2^k < k!$  IS: try n = k+1  I'm told to only work from one side, so I try the left side:  2^(k+1)   But I'm stuck here, any ideas?

Im trying to solve the following question         In the second step  where do they get $k!=2^k-1?$


I have a problem with this part of the code. It seems that if I try to add something to a list of Client I get a NullPointerException. I really don't know why because if I debug this part of the code the variable of type Client has information. If someone can help me I would be grateful. Here is the part of the code where the exception appears:    public class Customers {     private ArrayList<Client> listaClienti;     public Customers()     {     }     public void addClient(Client c,int i)     {         listaClienti.add(i, c);     }     public void deleteClient(Client c)     {         listaClienti.remove(c);     }     public Client getClient(int id)     {         return listaClienti.get(id);     } }


I see many of you don't like greetings for some reason. Before you comment, let me refute some of them already.  One of your arguments is "when someone says hi, they're not really saying hi to me". Yes they are. Not only to you, but to everybody, because it isn't feasible to greet each person.  What's the big deal with that? Automatic systems for filtering? Come on... do I force you to greet anyone and add it to your questions? No! Why should you force me to NOT greet people? To "save text"? Why not limit vocabulary, BTW, and turn all question into ? That would certainly save text.    What about jokes, analogies and other related expressions? Even writing style itself, I myself have a writing style that takes up some more space than possible, and many people do. Should that be fixed to conform to some standards? The important thing is not to type as little as possible, but to be understood. Would you prefer more machine-like questions?  Questions are not programs you need to optimize to avoid losing time. I enjoy knowing someone will read what I wrote, knowing I'm not just writing to a machine that doesn't feel, but to an actual person that might be offended if I downvote, and happy if I help.

I edit a lot of posts every day. I often run across posts with 'Hi' and 'Thanks' on the top and the bottom of the post respectively. I also run across things like:     --User   Should these items be removed during the editing of the post by an editor?


While typing out a rather long comment, I noticed the "x characters remaining" turns read when you get below ~350 characters remaining:      That's great, but it turns to blue another ~100 characters later:      What's up with that?  I realize  blue can mean "caution", but this color arrangement doesn't make sense, especially since the overall theme of MSE is blue.

High voted comments are in black text and look boring and unremarkable, while comments with a few votes have the red "hot" color on them. (I have no idea what is with the blue 25 :P)  Could this be changed so that highly voted comments actually look highly voted?


First of all I know this is not a great question, but I am starting out at Python and trying to understand the mechanics of things along. The following code is the output from a Python 3.4 interpreter:  >>> a = 9 >>> b = a >>> a is b True >>> b is a True >>> hex(id(a)) '0x9a34e0' >>> hex(id(b)) '0x9a34e0'   Now I understand the above part, but when i assign b = 9:  >>> b = 9 >>> a is b True >>> b is a  True >>> hex(id(a)) '0x9a34e0' >>> hex(id(b)) '0x9a34e0'   I don't understand: why is b still the same object as a? Why isn't a newly freshly made object assigned to it? If we look for a parallel situation in case of lists this doesn't happen:  >>> x = [1, 2, 3] >>> y = x >>> x is y True >>> y is x True >>> hex(id(x)) '0x7fc588004e48' >>> hex(id(y)) '0x7fc588004e48' >>> y = [1, 2, 3] >>> x is y False >>> y is x False >>> hex(id(x)) '0x7fc588004e48' >>> hex(id(y)) '0x7fc588009a48'   Why are ints variables still considered the same even after reassignment? In lists, though, I assigned the same list but a new object was made, which I understand.

Why does the following behave unexpectedly in Python?  >>> a = 256 >>> b = 256 >>> a is b True           # This is an expected result >>> a = 257 >>> b = 257 >>> a is b False          # What happened here? Why is this False? >>> 257 is 257 True           # Yet the literal numbers compare properly   I am using Python 2.5.2. Trying some different versions of Python, it appears that Python 2.3.3 shows the above behaviour between 99 and 100.  Based on the above, I can hypothesize that Python is internally implemented such that "small" integers are stored in a different way than larger integers and the is operator can tell the difference. Why the leaky abstraction? What is a better way of comparing two arbitrary objects to see whether they are the same when I don't know in advance whether they are numbers or not?


I created a CSV parser that parses CSV's from static resources.   I am returned with a Blob is not a Valid UTF-8 String error when parsing the character: "–" different from "-". The "–" is apparently still a unicode character:  .   The sheet is being saved as UTF-8 CSV and the data was exporting from Salesforce using data loader 38.0.   Can someone explain why this character is returning the Blob is not a Valid UTF-8 String even though the character appears to be a UTF-8 character?   CSV:     HEX with bad character:   00:00:00:XXX USER_DEBUG [XX]|DEBUG|4f626a6563742c437573746f6d5f446563696d616c5f5f632c437573746f6d5f5f632c42726f6b656e5f4669656c645f5f630d0a4d794f746865724f626a6563745f5f632c312c412c5858209620546869732068797068656e206973206275737465640d0a   HEX without bad character:   00:00:00:XXX USER_DEBUG [XX]|DEBUG|4f626a6563742c437573746f6d5f446563696d616c5f5f632c437573746f6d5f5f632c42726f6b656e5f4669656c645f5f630d0a4d794f746865724f626a6563745f5f632c312c412c58582020546869732068797068656e206973206275737465640d0a   ||||||Update:   Upon opening the file in Notepad, it appears the file was encoded in ANSI, even though excel states the file is encoding in UTF-8 when I open it. After saving at UTF-8 in Notepad, that resolved the symbol issue.   This did not work:     This did:     With this being said are there any capabilities within the blob class or another class to convert the file from ANSI to UTF-8 within Salesforce as opposed to relying on customers to ensure the file is in the correct encoding?

Im reading in a document that the user uploads from the visualFlow:  <apex:inputFile value="{!contentFile}" filename="{!nameFile}" id="file"/>   And its accessed in apex in this manner:  String nameFile = contentFile.toString();   And it works like a charm. I am able to parse through the document and extract all the information needed, but only for English users. But for Spanish users that's not the case.  Those files have some special characters, and cause a BLOB is not a valid UTF-8 string error.  I've tried to base64Encode the file contents, but the results come out illegible.   String nameFile= EncodingUtil.base64Encode(contentFile);


This question is different from the one marked as duplicate as I know how    to install Ubuntu on an USB Key but I want to have an additional partition on this USB Key    I have an USB 3.0 Stick with 64GB and I want to use it to save some backup data in an encrypted Partition but also have one partition with a bootable ubuntu.   Making a bootable ubuntu stick is easy:  # sudo dd if=ubuntu-16.04.2-desktop-amd64.iso of=/dev/sdX bs=1k count=2048 conv=fdatasync   (changed sdd to sdX to prevent users from copying it and harm their system)  But then I get a strange partition table:   # fdisk -l /dev/sdd Medium /dev/sdd: 58,4 GiB, 62746787840 Bytes, 122552320 Sektoren Einheiten: sectors von 1 * 512 = 512 Bytes Sektorengröße (logisch/physisch): 512 Bytes / 512 Bytes I/O Größe (minimal/optimal): 512 Bytes / 512 Bytes Typ der Medienbezeichnung: dos Medienkennung: 0x15e2543d  Gerät      Boot Start    Ende Sektoren Größe Id Typ /dev/sdd1  *        0 3035519  3035520  1,5G  0 Leer /dev/sdd2       14432   19295     4864  2,4M ef EFI (FAT-12/16/32)   This seems to be correct as my stick is booting fine. But I really don't understand it.   When I partion the usb device before and have one FAT32 and one LUKS parttion then I still can dd the iso to the first partition /dev/sdd1 but it is not bootable anymore.   I set the bootable flag on the first partition of course an my laptop tries to boot it but only shows a blinking underscore.   There are so many misleading informations in the web about this scenario. I am lost. I am familiar with partitioning, and MBR and GRUB but only in using it. It seems I never really understood what is going on and many things have changed since I last did it (EFI, loop devices..)   It seems to be very difficult to use an USB stick as a bootable ubuntu AND as a backup partition. But I still think this should be a matter of   Formatting and partitioning USB stick Copying ISO to partition Make some magic like MBR, bootable flag, Grub2   Can somebody help with a small step-by-step command line example to get things running on a modern ubuntu 16.04?  The second partition doesn't need to be mounted on Windows by the way.

If you are hurrying to reply, System → Administration → StartUp Disk Creator -- no, that's not what I'm talking about.   I want to try Ubuntu 11.04's Unity without touching my existing Ubuntu install.  To do this, I need to install the nVidia drivers first (sigh).  To do this, I need changes to persist a reboot.  To do this, I need to really install Ubuntu on a USB key.  How do you do that?    What I tried   I tried to make a USB key from , then boot from it, then choose "Install Ubuntu." The installer refused to install to the installation media itself. I tried, from my installed copy of Ubuntu:  sudo kvm /dev/sdb --cdrom .cache/testdrive/iso/ubuntu_natty-desktop-i386.iso   ...but the installer didn't detect the disk properly.


I've tried everything I found on the internet to make this program work but still nothing. I end up with a "Exception in thread "main" java.util.NoSuchElementException". The error definitely comes from the scanner but I can't figure out where. I would like to stop the user input when they enter an empty line. public static void main (String[] args) {   int count = 1;   Scanner sc = new Scanner(System.in);   String s = sc.nextLine();   Scanner sc2 = new Scanner(s);    while ( s != "" && count <= 10 )   {       int e = sc2.nextInt();       int m = sc2.nextInt();        int dt0_e = 365 - e;       int dt0_m = 687 - m;        if ( e%365 == 0 && m%687 == 0 ) // Case both Earth and Mars already are at day 0       {         System.out.println("Case "+count+": "+ 0);         count++;       }        else if ( dt0_e == dt0_m ) // Case both need the same number of days to reach day 0       {         System.out.println("Case "+count+": "+ dt0_e);         count++;       }        else // Other cases       {         int dtadd = dt0_e ;         int n = 1;          while ( (dtadd+m)%687 != 0 )         {           dtadd = dt0_e + n*365;           n++;         }       System.out.println("Case "+count+": "+ dtadd);       count++;       }       System.out.println(s);       sc2.close();       s = sc.nextLine();       sc2 = new Scanner(s);     }     sc.close(); }

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


Does anyone remember a book about Aliens that invaded earth and controlled people with a cap. The main character had a defective cap so he was able to think for himself. He went on an adventure to find freedom from the aliens. Does anyone remember anything like this?

I remember reading a series when I was around 7th or 8th grade about aliens who had taken over Earth by putting metal caps on people when they were "entering adulthood" to control them (not direct control, but it would keep them from rebelling). There was a faction of people who able to escape and had fake caps and would save teens who were about to be capped.  The main protagonist was a teen boy who was a boxer (or training to be a boxer or something). The aliens would hold tournaments for the humans and whoever won would be "worthy" to serve as personal slaves to the aliens.     The protagonist won and was able to get inside to try and learn more about the aliens from the inside.


On a fresh install of ubuntu 17.10 I enabled gnome extensions and logged out. When i logged back on the appearance changed completely.   No icons, Low resolution text   plus there is a new panel at the bottom. I guess this is the default gnome look. There wasn't even ubuntu dock. I had to add it. I tried changing themes but no luck. I would like to have my stock look restored. It looks ugly.

This is how my desktop looks after the update, the top bar turning grey and the addition of the bottom bar happened after the update.    From my searching of screenshots this does not appear to be how it is supposed to be. Is there any way to fix it?


I'm having an issue with getting Ubuntu 14.04 to load into the GUI after installation.  I get through the installation with no problems, the computer boots up and the Ubuntu logo appears on the screen.  I get to the login screen, but after that I just get dots on the screen.  Could someone help me out on this issue?  I have tried doing the full installation 3 times with the same result.

I am trying to boot Ubuntu on my computer.  When I boot Ubuntu, it boots to a black screen.  How can I fix this? Table of Contents:


Galaxies are moving away from us proportional to the distance between us and them , but nothing can travel faster than light, so even the farmost galaxies should be travelling away from us along with the space time with a speed less than that of light. In that case is our universe finite?

From watching cosmology lectures, it seems that the space between galaxies is expanding at an accelerating rate, my question is since it is the space that is (acceleratingly  expanding), the special relativity does not apply in this case? in other words since it is not anything that is accelerating with relative distance, would at some point galaxies that are far enough from each other separate faster than speed of light?  Please note, I am not asking if the galaxies would move faster than speed of light, but whether the rate of expansion of space be faster than speed of light so in effect each galaxy would be as if it is behind an event horizon where even light can not escape?    If yes, is there a name for such an event horizon that is cause by expanding space outside rather than the conventional black hole event horizon caused by stretching of space within the event horizon?   How would one be able to differentiate between a black hole even horizon and a galactic even horizon caused by accelerating expansion of space outside? (not sure if the concepts of inside and outside are still meaningful in such cases)


Can I use past tense in "now that" clause? Is the following sentence correct?  Now that Tony was no longer present, there was a distinct change in her attitude.

This morning I heard Jeremy Corbyn's speech at the Labour Conference.  Here is a section of that speech.  Can anyone tell me what tense he is using and why?  "Now is the time that government took a more active role in restructuring our economy. Now is the time that corporate boardrooms were held accountable for their actions,  And now is the time that we developed a new model of economic management to replace the failed dogmas of neo-liberalism …"  Is this a Britishism?  (I am American.)  Thanking your all in advance for any insights you can offer.


Let $S = \{ u,v,w \} $  List all equivalence relations on S. How many of these are also partial orders?  Well I found five total equivalences classes but right now I'm confused as to which are partial orders. The confusion is because I'm thinking in transitive terms. For example, one equivalence relation I found is:  $$\{ (u,u),(v,v),(w,w),(u,v),(v,u) \}$$  Anti symmetric means that $(u,v) \land (v,u) \rightarrow u=v$ but $u$ and $v$ are two different variables and so they're not the same. So this means that they're antisymmetric? I don't know why I'm stuck here.

On my assignment, one of the questions ask to list all equivalence relations on S and count how many are of partial orders.   Let S = {u, v, w}. List all equivalence relations on S. How many of these are also partial orders?   Am I to assume the equivalence relations are the possible combinations of each pair S x S ({}, {{u, u}}, {{u, u}, {u, v}} ...) or should their always be a given relation?


I wrote a command like this:  ${\cal F}_n=^{\text df}$   but at \text it gives an error. I wish to write df above = with \text but it doesn't go through. How should I fix it?  However $\textbf$ works fine, but I do not wish boldface, just text.

I am having trouble drawing the right hand side. Any ideas?


English has certain words that almost always go together. For example:  Wreak Excruciating Vastly  Reading that list, most native speakers will expect to see "havoc", "pain", and "superior" respectively. While you could "wreak destruction", that usage is very uncommon compared to "wreak havoc". My primary question: Is there a name for this kind of word relationship? Secondary questions:  Is there a reason this happens in our language? Can you list any other examples of these pairs?  Funny side note: Not knowing what to call this concept makes it a little tricky to pick meaningful tags.

Certain words you hear in English are only ever heard in a single context. For example, skirl is used to describe . Etymonline generously says the word is "rarely" heard outside that context, but I can't recall ever hearing it used for anything else. I imagine one could use it figuratively to describe another godawful high-pitched screech (sorry, bagpipe lovers), but there's no other bona fide usage for it.  What I want to know is stated in the title of the question: Is there a term for these one-off words? I'm sure there must be, but I can't think of what it might be.  Edit: Judging from some of the head-scratching comments I've received, there seems to be some confusion. Perhaps I did not make my meaning clear. I'm not looking for a word to describe the single instance of skirl. I'm asking about a class of words like skirl. I know there exist other examples of words that are only ever used in one context, but I can't think of any others at the moment.


I'm trying to describe a character who dances for her husband so that he doesn't get mad, apologizes profusely even if she hasn't done anything wrong. However, she is also strong-willed and determined. I considered using the word "altruist", but the character is not selfless.

I happen to be this type who always finds it hard to turn down someone who asks for my help.  You know, like when people ask to borrow some money, ask to take them to see a doctor, ask to help with English (I'm a nonnative speaker), ask to teach them some difficult subject, and anything. Moreover, this type of personality will not turn down one's request even if they are in a difficult situation themselves.  I don't think that the word kind or nice or selfless would be suitable for this.  I read  too, but the word altruist is used to describe someone who never asks for help, not for someone who can't say a "no" to someone else who asks them for help (which means that they may frequently ask for others' help too).  Besides, I don't know whether this is a negative or positive personality. So I can't figure out the right word to describe it.  Do I comprehend this in a weird way?


My situation is as follows: I am a Ukrainian citizen and have a one-year Italian residence permit for the purpose of studying that is valid until June 16. I am supposed to leave the Schengen zone on June 19. My passport allows me to stay 90/180 days in Schengen. I wanted to ask:   Can I stay in Schengen after my permit expires, having the Ukrainian passport, without the need to leave the Schengen zone and reenter?  In the following scenario: My permit is valid until June 16, but I leave Italy for Croatia (which is part of the EU but is not part of the Schengen Zone) on June 1 and then, re-enter on the very same day with my passport only without showing my permit anymore. Would my student status change to tourist status in this situation?

I have a 1-year residence permit from one Schengen country that is now expiring. Upon its expiration, I would like to get my 90/180 days validity as a tourist to stay, or return here as soon as possible.  I understand that the tourist short-stay scheme is based on the 90/180 days "counter". But what happens if my previous stay was not tourism but residence (as searching year). Wouldn't that mean that I can quickly exit and re-enter the Schengen area to activate my tourist stay?   Also, is there a way to change this purpose of stay without exiting the Schengen area?


I used the hello,world example of tikz-feynman, which should draw a horizontal Feynman diagram  \documentclass{standalone}  \usepackage{tikz} \usepackage{tikz-feynman}  \begin{document}  \feynmandiagram [horizontal=a to b] {   i1 -- [fermion] a -- [fermion] i2,   a -- [photon] b,  f1 -- [fermion] b -- [fermion] f2, };  \end{document}   But got a strange output like    Can you help me?

Today I downloaded and installed the new  package to draw Feynman diagrams. I included the packages   \usepackage{tikz}  \usepackage{tikz-feynman} \tikzfeynmanset{compat=1.0.0} \usetikzlibrary{shapes,arrows,positioning,automata,backgrounds,calc,er,patterns}   into my preamble (changed them already many times).  However, already a simple sample code like  \begin{tikzpicture} \begin{feynman} \vertex (a) {\(\mu^{-}\)}; \vertex [right=of a] (b); \vertex [above right=of b] (f1) {\(\nu_{\mu}\)}; \vertex [below right=of b] (c); \vertex [above right=of c] (f2) {\(\overline \nu_{e}\)}; \vertex [below right=of c] (f3) {\(e^{-}\)}; \diagram* { (a) -- [fermion] (b) -- [fermion] (f1), (b) -- [boson, edge label'=\(W^{-}\)] (c), (c) -- [anti fermion] (f2), (c) -- [fermion] (f3), }; \end{feynman} \end{tikzpicture}   directly gives the error:     Package pgfkeys Error: I do not know the key '/graph drawing/node distance'.   Can you please help me? Thanks in advance!


Non existing file  $ ls file_not_exists.txt ls: cannot access file_not_exists.txt: No such file or directory $ echo <> file_not_exists.txt  $ ls file_not_exists.txt  file_not_exists.txt $ cat file_not_exists.txt $   File with content  $ cat temp.txt  asdf $ echo temp.txt  temp.txt $ echo <> temp.txt   $ cat temp.txt  asdf    If the file does not exist, echo <> file_not_exists.txt will create a new file. So I think > works (redirecting the empty output into a newly created file). But if there is something in the file (like temp.txt), why it is not emptied by echo <> temp.txt?


The spell magic jar says with regards to the creature who's body the caster is possessing:      If the target has any class levels, you can't use any of its class features.   The , which is usually worded like (emphasis mine):     The [monster] is an Xth-level spellcaster. Its spellcasting ability is [Ability] (spell save DC X, +X to hit with spell attacks). The [monster] has the following [class] spells prepared   Nothing directly seems to imply that such a monster has "class levels". Do they?   If not, and by extension the possessor would keep the Spellcasting special trait, would the caster of magic jar now have spells and spell slots from their Spellcasting class feature and from the monster's Spellcasting?

I would like to know what happens if you use the Magic Jar spell to possess a creature which is capable of casting spells. Below are 3 different situations. I post all these questions in the same question because all of them are heavily related.  1st Situation: Creatures with Innate Spellcasting.  For example Kraken Priest (MM 215).  Would I be able to use its Innate Spellcasting? I mean, being able to cast its spells as the creature does (X uses per day). I don't say using my spell slots because that is impossible (eg. a Drow Elf Warlock can't use its spell slots to cast Darkness).  2nd Situation: Creatures with Spellcasting (similar to Pact Magic).  For Example Warlock of the Archfey (MM 219).  Would I be able to use its spellcasting? Note that this creature is an "11th-level spellcaster", not an "11th-level warlock" (its spellcasting isn't a class feature).  What would happen with the spell slots? Would I be able to cast its spells with my own slots? Would I be able to cast my spells with its slots?  3rd Situation: Creatures With Spellcasting (similar to Spellcasting of Clerics or Wizards)  For Example Diviner (MM 213).  Would I be able to use its spellcasting? Note that this creature is a "15th-level spellcaster", not a "15th-level wizard" (its spellcasting isn't a class feature).  What would happen with the spell slots (considering that for example, I'm a 16th-level Wizard)?   Would our spellcaster level sum (as if multiclassing)? Should I use the highest spellcaster level instead of summing them? Should I count the spellcaster level separated, each one with its spell slots separated? For example, Would I have 8 1st-level spell slots (4 + 4)?   Finally (without considering a specific situation):  Would I have to recalculate the spell's attack bonus and spell's DC if my mental stats are different from the creature's stats?  I know that these are a lot of multiple questions, but I don't think that posting them separately would be beneficial. If you think so, let me know and I will do that.


I have a batch file to unzip a file, the path of the zip file and destination folder is hardcoded. I want to unzip different zip files to different folders. I don't want to edit the code all the time, Please some one help on this.   @echo off  setlocal  cd /d %~dp0  Call :UnZipFile "G:\tett\" "G:\test\test.zip"  pause  exit /b   This is my batch file, here I am giving the paths of the source and destination. I want to pass the source and destination as arguments to run this batch. Thanks in Advance!

I need to pass an ID and a password to a batch file at the time of running rather than hardcoding them into the file.  Here's what the command line looks like:  test.cmd admin P@55w0rd > test-log.txt


In the below example, the \spvec macro generates a column vector nicely in the main body of the document, but it won't compile in the caption.  \documentclass[a4paper]{article}  %% Language and font encodings \usepackage[english]{babel}  \def\spvec#1{\left(\vcenter{\halign{\hfil$##$\hfil\cr \spvecA#1;;}}\right)} \def\spvecA#1;{\if;#1;\else #1\cr \expandafter \spvecA \fi}  \begin{document}  A $test=\spvec{1;2}$ vector.      \begin{figure}         \centering         \textbf{IMAGE HERE}         \caption{abc... $\spvec{1;2}$}     \end{figure}  \end{document}   The error is  Illegal parameter number in definition of \reserved@a. <to be read again>                     $ l.17        \caption{abc... $\spvec{1;2}$}

I'm trying to put a mathematics symbols in the caption of my figure with this:   \begin{figure}[!ht]     \centering     \includegraphics[scale=0.2]{vect_CM.png}     \caption{Vecteur $\overrightarrow{CM}$ à un moment donné}     \label{vect_CM} \end{figure}   And LaTeX show an error:  Illegal parameter number in definition of \reserved@a. <to be read again>                     \crcr  l.76 ...$\overrightarrow{CM}$ à un moment donné}   Do I have to use any package to do this?


What to do against Terran opponents who go for mass Battlecruisers? Most skytoss units seem to be garbage at that point. Are Archons at all viable in this scenario?

How should I prepare my army when attacking someone who has 12+ battlecruisers? (Protoss/Zerg/Terran answers are more than appreciated)


Above is a zener diode circuit used for voltage regulation.  In Art or Electronics textbook theres a following exercise about choosing the right zener:    Always Vz = Vout and 10mA is the zener current wanted;   so R = (Vin(max) - Vz) / 10mA = (25 - 10) / 10mA = 1.5k Ohm.  and for Pz = ( Vin(max) - Vout) / R - Iout(min) ) * Vz  Pz = ( (25 - 10) / 1.5k - 0mA ) * 10 = 100mW  But actually if we can use Pz = Vz * Iz   Pz = 10V * 10mA = 100mW  I found different answers to this question in different forums. Am I doing something wrong here?

I'm having trouble understanding the simple voltage regulator that can be built using a zener diode (from section 2.04 in the Art of Electronics).  I know that it would be better to use amplifiers, et cetera, but I'm just trying to understand how this circuit works.      I don't really understand how the circuit works, but I am guessing that when a load is applied to the output, it drains current from the source (Vin) and thus causes the voltage to drop?  How does the zener diode help to maintain the voltage and thus make this circuit act as a regulator?


A matching in a graph is a set of edges that are pair-wise non-adjacent. IOW, each node involved in the matching appears in only one edge.    Now I am wondering is there a ``generalized'' concept of matching, such that it still refers to an edge-set, and each vertex involved can appear in at most $k$ edges in this edge-set, where $k \ge 2$ is a pre-specified positive integer.  If such concept does exist, what are some interesting and representative problems studied for that?

While discussing the question I had asked , @NealYoung and I encounter another problem, which is to judge complexity of the problem below:     Given a connected undirected graph, finding a maximum-size subset of   the edges such that every vertex has degree at most two.   I have found some paper on complexity of relative problems. Most of them added more constraint on the original one.  added "with no odd cycles" and proved that it is NP-hard.  implied that the variant added "with no 3-cycle" is P referring to another paper (which I failed to find). But I have been unable to judge complexity of the original problem. So how to judge it? Thanks.


I have this Problem in Blender. After Pressing the smooth button in object mode, it creates a black line, which i think is shadow, around my object.    Link to image: (If above image doesn't display)   Thanks

While rendering a mesh with smooth shading on, I get a dark region/shadow on certain faces. The effect is more evident when smooth shading is applied to a mesh containing ngons, with the ngons turning black when rendered.   The blackening effect is visible in the viewport too.  How can I solve this problem?


I am trying to image 75 acer aspire's for the school I work for with Ubuntu 14.04 - it needed a couple extras like chrome and our wireless configuration for example.  I created a live boot using systemback and can boot into the image on another laptop but only from the flash drive. I obviously can't leave a flash drive in 75 laptops for third graders :) .  I can't find the installer as someone had pointed out on another forum I investigated.   How do I install the iso image onto the hard drives of the other laptops?

I'm a new Linux user. I've reinstalled my Wubi from scratch at least ten times the last few weeks because while getting the system up and running (drivers, , etc.) I've broken something (X, grub, unknowns) and I can't get it back to work. Especially for a newbie like me, it's easier (and much faster) to just reinstall the whole shebang than try to troubleshoot several layers of failed "fixing" attempts. Coming from Windows, I expect that there is some "disk image" utility that I can run to make a snapshot of my Linux install (and of the boot partition!!) before I meddle with stuff. Then, after I've foobar'ed my machine, I would somehow restore my machine back to that working snapshot. What's the Linux equivalent of Windows disk imagers like  or ?  Note: I found a similar question:


I saw a problem   which state to evalute $$\sum_{m=1}^{\infty}\sum_{n=1}^{\infty}\frac{1}{m^2n+n^2m+2mn}$$ My attempt Let $$f(m,n)=\sum_{m=1}^{\infty}\sum_{n=1}^{\infty}\frac{1}{m^2n+n^2m+2mn}$$   and interchanging $m,n$ as $n,m$ we have $$f'(n,m) = \sum_{m=1}^{\infty}\sum_{n=1}^{\infty}\frac{1}{mn^2+nm^2+2mn}$$ then I add $f(m,n)+f'(n,m)$ which gives the same which gives me the twice the original series. I failed to evaluate the series with the process I have applied.  How do I evaluate the series?  Any help will be appreciated.

I try to solve the following sum:  $$\sum_{k=1}^{\infty}\sum_{n=1}^{\infty} \frac{1}{k^2n+2nk+n^2k}$$  I'm very curious about the possible approaching ways that lead us to solve it. I'm not experienced with these sums, and any hint, suggestion is very welcome. Thanks.


If $a,b,c$ belong to set of real numbers and $ a^2+b^2+c^2=1$ then prove that $ab+bc+ca$ belongs to $[-\frac12,1]$  I have tried AM>GM>HM(progressions mean inequality) but I am unable to do anything. I have even attempted to assume a,b and c to be sides of an triangle and using $|a-b|<|c|$ and squaring but still I don't get the right-hand limit right.  Please tell me how to prove it.

If $a^2+b^2+c^2=1$, prove that $\frac{-1}{2}\le\ ab+bc+ca\le 1$.  I was able to prove that $ ab+bc+ca\le 1$. But I am unable to gain an equation to prove that $ \frac{-1}{2}\le\ ab+bc+ca$ .  Thanks in advance !


Looking for 50+ year old sci fi book. The Dulgari (sp?) empire has the humans on the run. The hero is a military man who has battled the Dulgari. There are always more of their ships than ours. The initial battle he goes through a series of pre-programmed ship movements, to a draw. Ends up tricking aliens to bring fleet to earth. He signals a "drive mechanism" to start that blows up sun and destroys their fleet and give humans advantage. I remember there being a drink called the "9 Planets".

In the book, humans were in a long war with an alien race that had a slight upper hand in numbers and technology, and so were slowly losing ground.  At the start of the war, Earth had cut itself off from all contact with the rest of humanity; I think this was hundreds of years before the events in the book.  As the book opens, a single spaceship from Earth arrives at the human's capital world, IIRC to pick up an ambassador to travel to the alien's home world for peace negotiations.  Some more plot points dredged from memory:    The Earth ship had a small crew, somewhere around 4 or 5. The Earth humans had psychic powers, but galactic humans didn't. Earth had gone through a lot of social upheaval during its isolation from the rest of the galaxy. I think the aliens were telepathic (the Earth humans didn't tell the galactic ambassador about all their plans because he couldn't shield his thoughts).   The ending went along these lines:      After the peace mission, the aliens invade Earth with a large part of their military and trigger a booby trap that destroys them along with Earth.  After that, the balance of power is in humanity's favor.   If it helps, I would have read the book in the late 1970s or early 1980s, but I believe it was published some time before that.


I am on level 1758 online on my computer and only on level 40 on my phone app.  Is there anyway to transport all the levels on my computer that are completed over to my phone?

I passed level 365, but it doesn't let me move ahead on the phone. Works fine on computer.


I run MemTest86 a lot at work on customer's machines, and it's great for troubleshooting memory issues. My question is, how can I test that a GPU is starting to go?  I know of programs like 3DMark to push the graphics card to its limits, but what about with Video Memory? Is it worth testing? Is there a stress tool actually able to catch issues in the video card (memory), perhaps using CUDA/OpenCL?

I want to test the memory of my video card because there are vertical lines on my screen. I have done some basic troubleshooting and it seems that the problem is in the video card. I want to validate that the issue is the video card by testing its memrory. I have found software that is used for Nvidia cards with CUDA support, but my card is the Nvidia GeForce 7600, which has no CUDA support.


Let's say I have a GameObject A that's moving in a circular path in orbit around a central point, and I have a second GameObject B that is capable of independent movement, and can move at a higher velocity than A.  B may be located at an arbitrary point, either inside or outside of A's orbit.  I want to calculate the fastest route that will cause object B to intercept object A.  (The problem is not exactly "I want a spaceship to arrive at a planet", but close enough for the purposes of this question.)  The obvious idea is to compute a bunch of concentric circles around B and use some sort of divide-and-conquer guesswork to narrow in on a circle that ends up touching A's orbit at exactly the point where A would be if B moved to that point at its maximum speed.  But that feels a bit clunky, not to mention computationally expensive for something that I'd want to do fairly frequently, potentially multiple times per frame.  Is there a better way to calculate this?  For simplicity's sake, assume that all calculations are occurring in a 2D plane.

I am creating a 2d space game and need to make the spaceship intercept a planet. I have working code for straight line intercepts but cannot figure out how to calculate the planets location in a circular orbit.  The game is not scientifically accurate so I am not worried about inertia, gravity, elliptical orbits, etc.  I know the spaceships location and speed and also the planets orbit (Radius) and speed


I really don't like how Linux ls -al mixes files and directories.   Is it possible to list directories, then files, with single command?   dirA dirB dirC fileA fileB fileC

I have two questions. First, which command lists files and directories, but lists directories first?  Second question: I want to copy a list of files into a single directory, but make the target directory the first filename in the command.


I have a page of dynamically loaded elements that respond as they should with click events. When I click on one of the elements the data loads into a shopping cart and that what's not responding. Specifically, it's a trash icon.  The window does not refresh when I click on the item to send it to the cart.  This sends the data to the cart. It is not wrapped in $(document).ready() fyi  $("#product-add-to-cart").click(e => {        let cart_data = ""       let modal_data = ""        const cartImg = image1       const itemTitle = title       const subTotal = parseFloat(subtotal.innerText)        // --------- Added to Cart -------------       cart_data += `<img src="../${cartImg}" alt="cart-img" id="cart-image">`       cart_data += '
'       cart_data += `<span id="cart-item-title" class="font-weight-bold mb-0">${itemTitle}</span>`       cart_data += '
'       cart_data += '
'       cart_data += '$'       cart_data += `<span id="cart-item-price" class="cart-item-price" class="mb-0">${subTotal}</span>`       cart_data += '
'       cart_data += ''       cart_data += '<ion-icon name="trash"></ion-icon>'       cart_data += ''        $(".cart-item").html(cart_data)   These are the functions I've tried. This is in a different JS file but I tried the functions in both files and it was the same.  $("#cart-item-remove").click((e) => {     console.log(e.target)   })   $("#cart-item-remove").on("click", "a", function(e){       console.log('delete')   })   I found other similar threads and one suggested .on() but it has an additional argument and I wasn't sure how to apply it.

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


"I was thoroughly gruntled."  Are there many words like 'disgruntled' where there is no positive counterpart? And was there ever a word 'gruntled'? And if not, where did 'disgruntled' derive from?

I remember hearing once about the etymology of disgruntled, probably based around a joke about how people can not be gruntled. The explanation given was that there was never a word gruntled, rather the dis‑  in disgruntled is actually a usage of the old prefix where it acts like an amplifier.   Firstly, is this true?  Secondly, are there any other words that use this prefix in this way?


I have: ASUS P4V800D-X Intel Pentium 4 HT 2.80GHz 2.5GB RAM 40GB HDD nVidia 9500GT  When I installed nVidia drivers downloaded from nvidia.com website (selected recommended drivers), I simply can't boot into desktop. I pass through purple screen, and then I get black screen with flashing white underscore on left hand side. Keyboard shortcuts are not working and the only way to get to desktop mode is booting into recovery mode (holding shift when booting etc.). In recovery mode I run:  sudo apt-get remove --purge nvidia*   and that is the only way to get a "normal" desktop environment. I put a quotes on a normal because computer is running slow and I can't set proper resolution.  Also, I've tried to install drivers via ubuntu GUI interface (proprietary, tested drivers), but with no luck.  I am using Ubuntu 14.04

I've  and rebooted my machine and now I get a black or blank screen.   How can I fix this?


I’m working on an aes encryption and decryption project in 8086 assembly! I managed to code an encryption algorithm and it worked perfectly. No I’m working on the decryption algorithm. I’ve managed to code all the inverse transformations. But how about the inverse key expansion?? How is the aes key expansion preformed during the decryption process?? Thanks, Ilay

The usual implementation of AES first computes all the Round Keys sequentially starting from the key, and stores them in RAM for later uses. However, when enciphering a single block with a key that will be used for that purpose only, or when RAM is very sparse, or perhaps in hardware, it is advantageous to use the Round Keys a they are being generated, rather than store them. Quoting the :     The key schedule can be implemented without explicit use of the array W[Nb*(Nr+1)]. For implementations where RAM is scarce, the Round Keys can be computed on-the-fly using a buffer of Nk words with almost no computational overhead.   It is said this also works for deciphering:     The key expansion operation that generates W is defined in such a way that we can also start with the last Nk words of Round Key information and roll back to the original Cipher Key. So, calculation ’on-the-fly' of the Round Keys, starting from an “Inverse Cipher Key”, is still possible.   However, the how-to is left as an exercise to the reader. In particular: Can the last Round Key (the first used when deciphering) be computed directly, rather than sequentially?


Sorry if it's a duplicate question, but I've been searching for solution since yesterday and I haven't found out yet..   I'm using CLion on mac, and my compiler is from xcode so i think it's clang. Any help would be appreciated!! Do I need to use gcc? or do I need to fix my cmake?  here's an error message.  [ 33%] Linking CXX executable bag Undefined symbols for architecture x86_64:   "Bag<int>::add(int)", referenced from:       _main in main.cpp.o   "Bag<int>::print()", referenced from:       _main in main.cpp.o   "Bag<int>::Bag()", referenced from:       _main in main.cpp.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) make[3]: *** [bag] Error 1 make[2]: *** [CMakeFiles/bag.dir/all] Error 2 make[1]: *** [CMakeFiles/bag.dir/rule] Error 2 make: *** [bag] Error 2   Here's main.cpp  #include <iostream> #include "Bag.h"  int main() {     Bag<int> temp;     temp.add(1);     temp.print();      cout << endl;      return 0; }   Here's Bag.h.  #ifndef BAG_BAG_H #define BAG_BAG_H  #include <vector> #include <cstdlib> #include <iostream> using namespace std;  static const size_t CAPACITY = 100;  template <class T> class Bag{ public:     Bag();      size_t size() const;     bool empty();     bool check(const T& item);      void resize(size_t new_size);     void clear();     void remove(const T& item);     void add(T item);     void print();  private:     T* data;     size_t _size; };   #endif //BAG_BAG_H   Here's Bag.cpp.  #include "Bag.h"  template <class T> Bag<T>::Bag() : data{new T[CAPACITY]}, _size{0} {}  template <class T> size_t Bag<T>::size() const {return _size;}  template <class T> bool Bag<T>::empty() {  }  template <class T> bool Bag<T>::check(const T &item) {  }  template <class T> void Bag<T>::resize(size_t new_size) {     T* temp = new T[new_size];      for(int i = 0; i == _size; i++)         *data++ = *temp++;      delete [] data;     this->data = &temp; }  template <class T> void Bag<T>::add(T item) {     data[_size + 1] = item;     _size++; }  template <class T> void Bag<T>::print() {     for(int i = 0; i == _size; i++)         cout << data[i] << " "; }   here's CMakeLists.txt  cmake_minimum_required(VERSION 3.15) project(bag)  set(CMAKE_CXX_STANDARD 14)  add_executable(bag main.cpp Bag.cpp Bag.h)

Quote from :     The only portable way of using templates at the moment is to implement them in header files by using inline functions.   Why is this?  (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)


I am using a few symbols from the fontawsome package to decorate tree generated with forest with tikz externalize. When I compile my tex document I see the following output:    Process started: pdflatex.exe -synctex=1 -interaction=nonstopmode "fonttest".tex  Syntax Warning: Could not parse ligature component "horizontal" of "ellipsis_horizontal" in parseCharName Syntax Warning: Could not parse ligature component "folder" of "folder_open_alt" in parseCharName Syntax Warning: Could not parse ligature component "open" of "folder_open_alt" in parseCharName Syntax Warning: Could not parse ligature component "alt" of "folder_open_alt" in parseCharName  Syntax Warning: Could not parse ligature component "444" of "_444" in parseCharName Syntax Warning: Could not parse ligature component "547" of "_547" in parseCharName  Process exited normally   When I do not externalize the warning is gone.  Not sure how should I handle this. The pdf looks ok, but not sure how it will be handled on other computers.  \documentclass[a4paper]{article} \usepackage{amsmath,amssymb,latexsym}  \usepackage[edges,external]{forest} \tikzexternalize[prefix=external-figures/] %if this is removed  Could not parse ligature component warning is gone  \usepackage{fontawesome} \pgfkeys{/forest,   namespace/.append style={content=\textbf{\{\}} ##1},   assembly/.append style={content=\faCogs \enskip \textbf{##1}},   class/.append style={content=\faObjectGroup \enskip ##1}, %\faClone   delegate/.append style={content=\faPaperPlaneO \enskip ##1},   enum/.append style={content=\faEllipsisH \enskip ##1},   interface/.append style={content=$\multimap$ ##1},   fldr/.append style={content=\faFolderOpenO \enskip ##1},   root/.append style={content=\textbf{##1}} }  \begin{document}   \begin{forest} for tree = {folder,grow'=0,fit=band,font=\scriptsize,inner ysep=1pt} [ {Legend}, root     [ {Assembly}, assembly         [ {Namespace}, namespace             [ {Class}, class ]             [ {Interface}, interface ]             [ {Enum}, enum ]             [ {Delegate}, delegate ]             [ {Folder}, fldr ]         ]     ] ] \end{forest}  \end{document}

In the following example, the 'ff' ligature in the figure labels (in 'differential') disappears when pdflatex is used, but the fault does not occur if latex-dvips-ps2pdf is used instead. Both lualatex and xelatex produce the correct results, using the pdf version of the figure. Is there a problem with the figure, or is this a bug in pdftex?  \documentclass{article} \usepackage{graphicx} \begin{document} \includegraphics[width=0.9\textwidth]{Cluster2} \end{document}


So i was about to evolve my two highest cp eevee hoping for some good cp. My 255 cp eevee evolved into a vaporeon with 700 cp . And my 205 cp eevee evolved into a 400 cp jolteon. Can someone explain how this works so i know for future evolutions?

When activating the evolution for a caught Pokemon, it seems to amplify the Combat Power (CP). Thus it seems most beneficial to evolve your Pokemon with the highest CP, if you have multiple of the same kind.   But what I am not sure about is whether it makes an efficiency difference if you spend candies and dust to boost CP before evolving, to gain more from the amplification? Or is it more efficient to just evolve without spending, and then using the leftover candies afterwards, since they now give a bigger CP boost per candy?   I only tested with a Rattata so far, which gained +8 CP per candy before evolving, and +15 CP afterwards. I collected no numbers on the amplification efficiency though, and now ran out of materials for further testing.  Or maybe it is a balanced calculation and makes no difference at all? I would love to have some insight on that.    Some data I collected thus far: (GPC = CP gain per candy)  79 CP Weedle (GPC 6) evolved to: 84 CP Kakuna (GPC 6), evolved at 90 CP to: 297 CP Beedrill    Note: The max-CP "half circle" in the profile stayed filled roughly at the same relative position throughout the evolutions.


I have two shapefiles with the same projection, but they could not overlay each other. I understand that the extent is different, but I could not figure out how to change it.  Here are the two layers properties:

I put 4 different layers into my ArcMap document, but only one of them will show up on the map! I should be seeing the other 3 layers as well. When I do a Zoom to layer, I can see one layer, but I cannot figure out how to make the other 3 show up at once on top of each other.  Before I opened ArcMap, I used ArcCatalog where I right-clicked 3/4 of the shapefiles and  clicked Properties → Coordinate system → Import and then clicked on my Trees layer, which has the coordinate system I want the other 3 to have. But when I opened ArcMap the 4 layers did not overlap, nor could I move them above or below each other.


How do I create perspective with repeating patterns? I am very much a beginner level, as noted by my first attempt to create a illustration in illustrator. However, my attempt has provided me with various questions and obstacles on how to achieve the  Hand-drawn illustration.  For instance, in the picture below – there is repeating previously design pattern. What technique could be used to create depth?     The end result should yield a perspective similar to this live trace.  This may be off topic so please let me know how far or nebulous this question appears.

I created a curving arrow shape that starts wide at the bottom and thins out near the top where the point is. I also created a brick pattern swatch but when I apply it to the shape it appears like the pattern is overlaid instead of like a real road where the bricks follow the shape and narrows near the most distant point. How can I apply a perspective to the brick pattern without looking like I used a clipping mask?  Here is a link to what I achieved with a clipping mask - not what I want though. I need the bricks to look like they are inlaid just like in real life.


Most of the particles have different velocity in different reference of frames but why is speed of light the same in all refrence frames?  After all light is made of a photon.

I was told that the Galilean relative velocity rule does not apply to the speed of light. No matter how fast two objects are moving, the speed of light will remain same for both of them.   How and why is this possible?   Also, why can't anything travel faster than light?


I am attending a qualitative methods conference in social science, and one of the speaker argues the following.  In the two graphs below, a researcher using regression would see two regression lines with identical slopes and different intercept -- thus, he would not detect any difference.  In contrast, for a qualitative researcher, the first graph is a perfect case of X being a necessary condition for Y (i.e. Y < X, or Y is limited by X), while the second graph is a perfect case of X being a sufficient condition for Y (i.e. Y > X, or X guarantees a minimum level of Y).     Link to .  Implicitly, the speaker is saying that regression cannot make the distinction that qualitative researchers can. Is this convincing to you? Is there quantitative tool to derive the necessary / sufficient distinction from this bivariate data?

I have been thinking about how to use regression to prove whether X factor is a necessary or a sufficient condition for Y. I am employing these terms in the traditionally logical sense, i.e.   If no X, then no Y --> X is necessary for Y If X, then Y --> X is sufficient for Y   The reason I'm asking is because in social sciences theories we talk about necessary and sufficient conditions all the times (e.g., "(If) No bourgeoisie, (then) no democracy"). At the same time, the most prevalent tool is regression, yet it seems ill-fitted to investigate necessary / sufficient causes.  Indeed, rarely do we talk about necessity and sufficiency in the context of regression. The usual interpretation is that X "causes" Y in an additive sense -- i.e. a certain change in X is associated / caused a certain change in Y.  So, is it possible to interpret regression results as evidence of necessity versus sufficiency? In contrast, a simple 2-by-2 table of X and Y would make the necessity / sufficiency relationship very clear.  P/S: the motivation needs not be restricted to social sciences. For example, if I have a dataset with DV as "Fire occurring", and IVs as presence of fuel, presence of match, presence of lightning, etc. Can we use regression to prove that fuel is necessary but insufficient for fire?


$$\int \dfrac{1}{1+\sqrt{\tan x}}\quad dx$$ $$\int \dfrac{\sqrt{\sin x}}{\sqrt{\sin x} + \sqrt{\cos x}}\quad dx$$ It is difficult for me to solve this integration.

We have to evaluate the following integral:  $$\int \frac{\sqrt{\sin x}}{\sqrt{\sin x} + \sqrt{\cos x}} dx$$  I tried this:  I multiplied both the numerator and denominator by $\sec x$ And substituted $\tan x = t$.  But after that I got stuck.  The book where this is taken from gives the following as the answer: $$\ln(1+t)-\frac14\ln(1+t^4)+\frac1{2\sqrt2}\ln\frac{t^2-\sqrt2t+1}{t^2+\sqrt2t+1}-\frac12\tan^{-1}t^2+c$$ where $t=\sqrt{\cot x}$


Consider following two programs.  p1.cpp  #include <iostream> struct test {     void fun(); }; int main() {     test t;     t.fun(); }   p2.cpp  #include <iostream> void test::fun() {     std::cout<<"fun() is called\n"; }   I am compiling like following.  g++ -c -o p1.o p1.cpp g++ -c -o p2.o p2.cpp   <--------- This gives me compiler error.   How can I solve this error? What I am doing wrong?

I am new to C++ and I had a few general questions about code separation. I have currently built a small application, all in one file.  What I want to do now is convert this into separate files such that they contain similar code or whatnot.  My real question right now is, how do I know how to separate things? What is the invisible margin that code should be separated at?    Also, what's the point of header files? Is it to forward declare methods and classes so I can use them in my code before they are included by the linker during compilation?    Any insight into methods or best practises would be great, thanks!


Now that we don't have permeating Ether anymore, why don't we consider the omnipresent Cosmic background radiation in place of it? and measure Speeds with respect to the CMBR? In that way an object moving through the space, can be said to have at least a 'kind-of' absolute velocity w.r.t Background radiation? I.O.W is that radiation stationary?

OK...before everyone blasts this with references to the relativistic invariance of the physical laws, time dilation, etc let me add some context. Also, I am an amateur with an interest in physics, so I don't know the details of the physics. However, I have read enough about the cosmological principle and cosmic time to develop this "confusion" .  Based on evidence gathered to-date, it appears that the universe is both , as evidenced by observations and the . This principle, when combined with the FLRW metric, allows space-time to be divided into non-intersecting slices and therefore establish a "cosmic time."   Now, the existance of such a time in no way suggests that it is the "right" time or a true "now", hence violating relativity -- although some presentist philosophers (e.g., W.L. Craig) have tried to make this argument, but it is not generally accepted in philosophical circles.  However, this leaves me confused about an apparent disconnect between relativity and the cosmological principle:  Isotropy only holds if we are at rest relative to the cosmic microwave background radiation (universal rest frame), o/w anisotropy is present - yet each reference frame is supposed to allow equally valid observations. How can these two be reconciled when most reference frames would lead us to conclude that the universe is NOT isotropic?  It seems that only by appealing to the idea of being at rest relative to "universal rest frame" can we explain away any discrepancies from isotropy as due to "peculiar motion". However, doesn't this give this "universal rest frame" and its associated time an empirically privileged status, even though physical laws work just fine in every reference frame?   For example (pardon any abuse of astronomy): if look off in some part of space and see only quasars, and then in another part of space and see only brown dwarfs, but I measure both as apparently the same distance from me, then can I conclude that we are in motion, since otherwise we would have an empirical contradiction (kind of like finding dinosaur and human remains in the same strata)?  Any help on where I am going wrong would be helpful. Intuitively, I don't think there should be a way to establish absolute ordering between space-like separated events, but the above reasoning suggests otherwise.


This is the output figures for some machine learning experiments I'm doing. What are the factors that influence the entity of the fluctuations in my validation accuracy?

I am building some image classification model with reasonable size data (~3K) images in both training and validation set. However, I noticed the performance on validation set is not stable. For example, here are outputs over 10 epochs (acc means accuracy binary classification on balanced data) epoch [1]: training loss: 2.27 - acc: 0.50 - val_loss: 3.29 - val_acc: 0.49 epoch [2]: training loss: 1.55 - acc: 0.50 - val_loss: 0.92 - val_acc: 0.50 epoch [3]: training loss: 1.07 - acc: 0.51 - val_loss: 1.43 - val_acc: 0.53 epoch [4]: training loss: 0.87 - acc: 0.58 - val_loss: 1.85 - val_acc: 0.61 epoch [5]: training loss: 0.59 - acc: 0.72 - val_loss: 0.58 - val_acc: 0.61 epoch [6]: training loss: 0.52 - acc: 0.79 - val_loss: 2.30 - val_acc: 0.50 epoch [7]: training loss: 0.38 - acc: 0.85 - val_loss: 0.17 - val_acc: 0.86 epoch [8]: training loss: 0.32 - acc: 0.88 - val_loss: 1.52 - val_acc: 0.60 epoch [9]: training loss: 0.21 - acc: 0.91 - val_loss: 0.14 - val_acc: 0.88 epoch [10]: training loss: 0.34 - acc: 0.88 - val_loss: 2.81 - val_acc: 0.49  We can see that in training, it seems fine, but for epoch 6 and 8 validation loss was very high, and the final epoch 10, the validation loss got so high that the model become useless. What could be the reason causing this? If it is overfitting on training data, why we are not seeing steady increase on validation loss?


I have been copying from class text to a blade on Sharelatex, and it seems the teachers use the symbol (\!) a lot.  \sin\!\left(x\right)=\frac{-1}{\sqrt{2}} \cos\!\left(\frac{\pi }{12}\right)   Why do they need to use the symbol for exclamation mark(!) ?

I have noticed that I hardly ever use the \negthinspace command  \!.  This is because I don't know how to use it properly (I do use other spacing commands quite a bit, because I can better understand the guidelines of when they might be useful). When might it be considered appropriate to use this spacing command?