Search Results

Search found 4717 results on 189 pages for 'namespace'.

Page 139/189 | < Previous Page | 135 136 137 138 139 140 141 142 143 144 145 146  | Next Page >

• C++ Boolean problem (comparison between two arrays)

  - by Martin

  Hello! I have a problem to do. I already did some part of it, however I stuck and don't know exactly what to do next. The question: " You are given two arrays of ints, named A and B. One contains AMAXELEMENTS and the other contains BMAXELEMENTS. Write a Boolean-valued function that returns true if there is at least one point in A that is the same as a point in B, and false if there is no match between two arrays. " The two arrays are made up by me, I think if I know how to compare two arrays I will be fine, and I will be able to finish my problem. This is what I have so far (I changed AMAXELEMENTS to AMAX, and BMAXELEMENTS to BMAX): #include <iostream> using namespace std; int main(){ const int AMAX=5, BMAX=6; int i; bool c1=true,c2=false; int A[AMAX]={2,4,1,5,9}; int B[BMAX]={9,12,32,43,23,11}; for(i=0;i<BMAX;i++) if (B[i]==A[i]) // <---- I think this part has to look different, but I can't figure it out. cout<<c1<<endl; else cout<< c2<<endl; return 0; }

  Read the article

• Java : Inner class of an interface (from google guice)

  - by bsreekanth

  Hello, I was going through the source of google guice, and found an unfamiliar piece of code. It would be great learning if someone can clarify it. I have very basic understanding of inner classes, as they keep the implementation details close to the public interface. Otherwise the inner class may pollute the namespace. Now, I see the below lines at public static final Scope SINGLETON = new Scope() { public <T> Provider<T> scope(final Key<T> key, final Provider<T> creator) { return new Provider<T>() { ......... } It assign an inner class instance to the static variable, but Scope is an interface defined as (at) public interface Scope Is it possible to instantiate the interface?? or is it a succinct syntax for an anonymous implementation of an interface?? If anyone can explain what the author is intended by multiple nested classes above (Scope and Provider), and why it make sense to implement this way, it would help me to understand. thanks.

  Read the article

• XAML PixelGrid to Prevent Blurry Text

  - by Bodekaer

  Hi, Just wanted to share a small Grid I created, which can help prevent blurry text etc. as it adjusts the margin of the Grid to ensure a pixel perfect position and size of the grid. Works great e.g. for inside StackPanels with auto height Labels/TextBlocks. Here is the code: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Windows; using System.Windows.Controls; using System.Windows.Media; namespace Controls { class PixelGrid : Grid { protected override void OnRenderSizeChanged(SizeChangedInfo sizeInfo) { // POSITION Vector position = VisualTreeHelper.GetOffset(this); double targetX = Math.Round(position.X, MidpointRounding.ToEven); double targetY = Math.Round(position.Y, MidpointRounding.ToEven); double marginLeft = targetX - position.X; double marginTop = targetY - position.Y; // SIZE double targetHeight = Math.Round(sizeInfo.NewSize.Height, MidpointRounding.ToEven); double targetWidth = Math.Round(sizeInfo.NewSize.Width, MidpointRounding.ToEven); double marginBottom = targetHeight - sizeInfo.NewSize.Height; double marginRight = targetWidth - sizeInfo.NewSize.Width; // Adjust margin to ensure pixel width this.Margin = new Thickness(marginLeft, marginTop, marginRight, marginBottom); base.OnRenderSizeChanged(sizeInfo); } } }

  Read the article

• How to focus a control in an MDIParent when all child windows have closed?

  - by Tim Gradwell

  I have a control in my parent mdi form which I wish to be given the focus if all mdi children have closed. I've tried hooking into the child form's FormClosed event and setting the focus from there but when I test it, my control is not left with focus when I close the mdi child. Can anyone tell me what I'm missing? In the sample below, "first focus" gets hit and does its job correctly (if I comment out the first focus line, my tree does not get focus on startup, so it must be doing its job, right?) Unfortunately, even though "second focus" gets hit, my tree does not end up with the focus when I close the child window. Sample using System; using System.Windows.Forms; namespace mdiFocus { class ParentForm : Form { public ParentForm() { IsMdiContainer = true; tree = new TreeView(); tree.Nodes.Add("SomeNode"); tree.Dock = DockStyle.Left; Controls.Add(tree); } protected override void OnShown(EventArgs e) { Form child = new Form(); child.MdiParent = this; child.Show(); child.FormClosed += new FormClosedEventHandler(child_FormClosed); tree.Focus(); // first focus works ok } void child_FormClosed(object sender, FormClosedEventArgs e) { tree.Focus(); // second focus doesn't seem to work, even though it is hit :( } TreeView tree; } static class Program { [STAThread] static void Main() { Application.Run(new ParentForm()); } } }

  Read the article

• What is jQuery for Document.createElementNS()?

  - by C.W.Holeman II

  What is jQuery for Document.createElementNS()? function emleGraphicToSvg(aGraphicNode) { var lu = function luf(aPrefix){ switch (aPrefix){ case 'xhtml': return 'http://www.w3.org/1999/xhtml'; case 'math': return 'http://www.w3.org/1998/Math/MathML'; case 'svg': return 'http://www.w3.org/2000/svg'; } return ''; }; var svg = document.evaluate("svg:svg", aGraphicNode, lu, XPathResult.FIRST_ORDERED_NODE_TYPE, null). singleNodeValue; $(svg).children().remove(); rect = document.createElementNS(lu('svg'), "rect"); rect.setAttribute("x", "35"); rect.setAttribute("y", "25"); rect.setAttribute("width", "200"); rect.setAttribute("height", "50"); rect.setAttribute("class", "emleGraphicOutline"); svg.appendChild(rect); } The code is a simplified fragment from Emle - Electronic Mathematics Laboratory Equipment JavaScript file emle_lab.js. The Look-Up-Function, luf(), maps a complete reference to a shorten name for the namespace in the XPath string and createElementNS(). The existing svg:svg is located, removed and replaced by a new rectangle.

  Read the article

• How to allow devise users to edit their profil?

  - by user1704926

  I have a namespace called "backend" which is protected by Devise. I would like now to allow users to edit their profil. So I created a users_controller in Backend. Here's the users_controllercode : class Backend::UsersController < ApplicationController layout 'admin' before_filter :authenticate_user! def index @users = Backend::User.all respond_to do |format| format.html # index.html.erb format.json { render json: @users } end end def show @user = Backend::User.find(params[:id]) respond_to do |format| format.html # show.html.erb format.json { render json: @user } end end def edit @user = Backend::User.find(params[:id]) end def update @user = Backend::User.find(params[:id]) respond_to do |format| if @user.update_attributes(params[:user]) format.html { redirect_to @user, notice: 'Article was successfully updated.' } format.json { head :no_content } else format.html { render action: "edit" } format.json { render json: @user.errors, status: :unprocessable_entity } end end end end When I go on backend_users_path there is a list of all the users. I would like to permit to edit only his own profil. So I go on the Edit page : <%= link_to "Edit", edit_backend_user_path(backend_user.id) %> . Here's the Edit page code : <%= simple_form_for @user do |f| %> <div><%= f.label :email %><br /> <%= f.input :email, :autofocus => true %></div> <div><%= f.submit "Update" %></div> <% end %> And there is my problem : when I try to modify the email address, nothing happen. The update fails. How can I do this ? I'm quite lost. Thanks by advance.

  Read the article

• C++ reference variable again!!!

  - by kumar_m_kiran

  Hi All, I think most would be surprised about the topic again, However I am referring to a book "C++ Common Knowledge: Essential Intermediate Programming" written by "Stephen C. Dewhurst". In the book, he quotes a particular sentence (in section under Item 5. References Are Aliases, Not Pointers), which is as below A reference is an alias for an object that already exists prior to the initialization of the reference. Once a reference is initialized to refer to a particular object, it cannot later be made to refer to a different object; a reference is bound to its initializer for its whole lifetime Can anyone please explain the context of "cannot later be made to refer to a different object" Below code works for me, #include <iostream> using namespace std; int main(int argc, char *argv[]) { int i = 100; int& ref = i; cout<<ref<<endl; int k = 2000; ref = k; cout<<ref<<endl; return 0; } Here I am referring the variable ref to both i and j variable. And the code works perfectly fine. Am I missing something? I have used SUSE10 64bit linux for testing my sample program. Thanks for your input in advance.

  Read the article

• How do I pass references as method parameters across AppDomains?

  - by Thiado de Arruda

  I have been trying to get the following code to work(everything is defined in the same assembly) : namespace SomeApp{ public class A : MarshalByRefObject { public byte[] GetSomeData() { // } } public class B : MarshalByRefObject { private A remoteObj; public void SetA(A remoteObj) { this.remoteObj = remoteObj; } } public class C { A someA = new A(); public void Init() { AppDomain domain = AppDomain.CreateDomain("ChildDomain"); string currentAssemblyPath = Assembly.GetExecutingAssembly().Location; B remoteB = domain.domain.CreateInstanceFromAndUnwrap(currentAssemblyPath,"SomeApp.B") as B; remoteB.SetA(someA); // this throws an ArgumentException "Object type cannot be converted to target type." } } } What I'm trying to do is pass a reference of an 'A' instance created in the first AppDomain to the child domain and have the child domain execute a method on the first domain. In some point on 'B' code I'm going to call 'remoteObj.GetSomeData()'. This has to be done because the 'byte[]' from 'GetSomeData' method must be 'calculated' on the first appdomain. What should I do to avoid the exception, or what can I do to achieve the same result?

  Read the article

• How is covariance cooler than polymorphism...and not redundant?

  - by P.Brian.Mackey

  .NET 4 introduces covariance. I guess it is useful. After all, MS went through all the trouble of adding it to the C# language. But, why is Covariance more useful than good old polymorphism? I wrote this example to understand why I should implement Covariance, but I still don't get it. Please enlighten me. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Sample { class Demo { public delegate void ContraAction<in T>(T a); public interface IContainer<out T> { T GetItem(); void Do(ContraAction<T> action); } public class Container<T> : IContainer<T> { private T item; public Container(T item) { this.item = item; } public T GetItem() { return item; } public void Do(ContraAction<T> action) { action(item); } } public class Shape { public void Draw() { Console.WriteLine("Shape Drawn"); } } public class Circle:Shape { public void DrawCircle() { Console.WriteLine("Circle Drawn"); } } public static void Main() { Circle circle = new Circle(); IContainer<Shape> container = new Container<Circle>(circle); container.Do(s => s.Draw());//calls shape //Old school polymorphism...how is this not the same thing? Shape shape = new Circle(); shape.Draw(); } } }

  Read the article

• C++ Bubble Sorting for Singly Linked List [closed]

  - by user1119900

  I have implemented a simple word frequency program in C++. Everything but the sorting is OK, but the sorting in the following script does not work. Any emergent help will be great.. #include <stdio.h> #include <string.h> #include <stdlib.h> #include <ctype.h> #include <iostream> #include <fstream> #include <cstdio> using namespace std; #include "ProcessLines.h" struct WordCounter { char *word; int word_count; struct WordCounter *pNext; // pointer to the next word counter in the list }; /* pointer to first word counter in the list */ struct WordCounter *pStart = NULL; /* pointer to a word counter */ struct WordCounter *pCounter = NULL; /* Print statistics and words */ void PrintWords() { ... pCounter = pStart; bubbleSort(pCounter); ... } //end-PrintWords void bubbleSort(struct WordCounter *ptr) { WordCounter *temp = ptr; WordCounter *curr; for (bool didSwap = true; didSwap;) { didSwap = false; for (curr = ptr; curr->pNext != NULL; curr = curr->pNext) { if (curr->word > curr->pNext->word) { temp->word = curr->word; curr->word = curr->pNext->word; curr->pNext->word = temp->word; didSwap = true; } } } }

  Read the article

• returning a pointed to an object within a std::vector

  - by memC

  I have a very basic question on returning a reference to an element of a vector . There is a vector vec that stores instances of class Foo. I want to access an element from this vector . ( don't want to use the vector index) . How should I code the method getFoo here? #include<vector> #include<stdio.h> #include<iostream> #include<math.h> using namespace std; class Foo { public: Foo(){}; ~Foo(){}; }; class B { public: vector<Foo> vec; Foo* getFoo(); B(){}; ~B(){}; }; Foo* B::getFoo(){ int i; vec.push_back(Foo()); i = vec.size() - 1; // how to return a pointer to vec[i] ?? return vec.at(i); }; int main(){ B b; b = B(); int i = 0; for (i = 0; i < 5; i ++){ b.getFoo(); } return 0; }

  Read the article

• a simple program that counts and sums digits. How can I make it work?

  - by user1710386

  So I've to write a simple program(that loops) where you can enter an int and it spews out the number count and the sum of the numbers. Since I am such a tard when it comes to programming, I just scavanged the code online and tried to piece it together. I guess the sum block screws with n, but I am not really sure. Anyway, I would really appreciate it if somebody could point out mistakes and show me how can I make it work. #include <iostream> using namespace std; int main() { while(1) { int i,p,n,sum=0; //sum block cout<<"enter an int: "; cin>>n; { while(n!=0) { p=n % 10; sum+=p; n=n/10; } cout<<"int digit sum: "<<sum <<endl; } { int count = 0; while(n) { n /= 10; ++count; } cout <<"number of digits: " << count << '\n';} } }

  Read the article

• Using pair in c++

  - by user1543957

  Can someone please tell why i am unable to compile the following program #include<iostream> #include<string> #include<cmath> #include<iostream> #include<cfloat> #define MOD 10000009 using namespace std; double distance(pair<int,int> p1,pair<int,int> p2) { double dist; dist = sqrt( (p1.first-p2.first)*(p1.first-p2.first) + (p1.second-p2.second)*(p1.second-p2.second) ); return(dist); } int main() { int N,i,j; cin >> N; pair<int,int> pi[N]; for(i=0;i<N;i++) { cin >> pi[i].first >> pi[i].second; } for(i=0;i<N;i++) { cout << pi[i].first << " "<< pi[i].second << endl; } distance(pi[0],pi[1]); // This line is giving error return 0; }

  Read the article

• Infile incomplete type error

  - by kd7vdb

  I am building a program that takes a input file in this format: title author title author etc and outputs to screen title (author) title (author) etc The Problem I am currently getting is a error "ifstream infile has incomplee type and cannot be defined" #include <iostream> #include <string> #include <ifstream> using namespace std; string bookTitle [14]; string bookAuthor [14]; int loadData (string pathname); void showall (int counter); int main () { int counter; string pathname; cout<<"Input the name of the file to be accessed: "; cin>>pathname; loadData (pathname); showall (counter); } int loadData (string pathname) // Loads data from infile into arrays { ifstream infile; int counter = 0; infile.open(pathname); //Opens file from user input in main if( infile.fail() ) { cout << "File failed to open"; return 0; } while (!infile.eof()) { infile >> bookTitle [14]; //takes input and puts into parallel arrays infile >> bookAuthor [14]; counter++; } infile.close; } void showall (int counter) // shows input in title(author) format { cout<<bookTitle<<"("<<bookAuthor<<")"; } Thanks ahead of time, kd7vdb

  Read the article

• Converting a soap message to a document using wssj

  - by ellander

  I have been supplied with a jar file that should enable me to connect to a 3rd party system. When I run the necessary class I get an error which states that the namespace for the prefix "SOAPENV" has not been declared. Using jad I have decompiled the class files to try suss out what is going on and the error seems to occur when a soap message is being converted to a document. Unfortunately I don't know much about wssj. Can anyone suggest what the problem might be? I'm wondering if it's an incompatibility issue as it's not a recently created jar file and the decompiled code looks different to all the examples I can find. For example, in this section the examples have addNamesSpaceDeclaration rather than addAttribute... MessageFactory factory = MessageFactory.newInstance(); SOAPFactory sf = SOAPFactory.newInstance(); SOAPMessage msg = factory.createMessage(); MimeHeaders headers = msg.getMimeHeaders(); headers.addHeader("Content-Type", "text/xml"); SOAPEnvelope env = msg.getSOAPPart().getEnvelope(); env.addAttribute(sf.createName("xmlns:xsi"), "http://www.w3.org/2001/XMLSchema-instance");

  Read the article

• What is PocoCapsule current status?

  - by seas

  What is PocoCapsule current status? Is it evolving? Has it been forked with some other product? What is about the whole idea of IoC for C++? If PocoCapsule is not evolving, is it because IoC was considered not useful for C++, unsafe, other patterns appeared or something else? As far as I understand there are 2-3, maybe few more products, that implement IoC for C++, available and PocoCapsule is the most mature of them. I see several disadvantages in current version (as I see it's 1.1 from google code): No separate namespace. Header files are required to be right in INCLUDE folder - better to place them in subfolder. Generation Tools depend on Java. No static linking libraries are built by default. Cannot generate source code out of setup.xml for compilation and link with my app if I don't need reconfiguration feature. Does anybody have the same thoughts? Does anybody work on something of this list? Are there any barriers to start working, like patents?

  Read the article

• C++ templates error: instantiated from 'void TestClass::testMethod(T, std::map) [with T = SomeClass]

  - by pureconsciousness

  Hello there, I've some problem in my code I cannot deal with: #ifndef TESTCLASS_H_ #define TESTCLASS_H_' #include <map> using namespace std; template <typename T> class TestClass { public: TestClass(){}; virtual ~TestClass(){}; void testMethod(T b,std::map<T,int> m); }; template <typename T> void TestClass`<T`>::testMethod(T b,std::map<T,int> m){ m[b]=0; } #endif /*TESTCLASS_H_*/ int main(int argc, char* argv[]) { SomeClass s; TestClass<SomeClass> t; map<SomeClass,int> m; t.testMethod(s,m); } Compiler gives me following error in line m[b]=0; : instantiated from 'void TestClass::testMethod(T, std::map) [with T = SomeClass] Could you help find the problem?? Thanks in advance

  Read the article

• C++ STL question related to insert iterators and overloaded operators

  - by rshepherd

  #include <list> #include <set> #include <iterator> #include <algorithm> using namespace std; class MyContainer { public: string value; MyContainer& operator=(const string& s) { this->value = s; return *this; } }; int main() { list<string> strings; strings.push_back("0"); strings.push_back("1"); strings.push_back("2"); set<MyContainer> containers; copy(strings.begin(), strings.end(), inserter(containers, containers.end())); } The preceeding code does not compile. In standard C++ fashion the error output is verbose and difficult to understand. The key part seems to be this... /usr/include/c++/4.4/bits/stl_algobase.h:313: error: no match for ‘operator=’ in ‘__result.std::insert_iterator::operator* [with _Container = std::set, std::allocator ]() = __first.std::_List_iterator::operator* [with _Tp = std::basic_string, std::allocator ]()’ ...which I interpet to mean that the assignment operator needed is not defined. I took a look at the source code for insert_iterator and noted that it has overloaded the assignment operator. The copy algorithm must uses the insert iterators overloaded assignment operator to do its work(?). I guess that because my input iterator is on a container of strings and my output iterator is on a container of MyContainers that the overloaded insert_iterator assignment operator can no longer work. This is my best guess, but I am probably wrong. So, why exactly does this not work and how can I accomplish what I am trying to do?

  Read the article

• Need help in Hashtable implementation

  - by rafael

  Hi all, i'm quite a beginner in C# , i tried to write a program that extract words from an entered string, the user has to enter a minimum length for the word to filter the words output ... my code doesn't look good or intuitive, i used two arrays countStr to store words , countArr to store word length corresponding to each word .. but the problem is i need to use hashtables instead of those two arrays , because both of their sizes are depending on the string length that the user enter , i think that's not too safe for the memory or something ? here's my humble code , again i'm trying to replace those two arrays with one hashtable , how can this be done ? using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Collections; namespace ConsoleApplication2 { class Program { static void Main(string[] args) { int i = 0 ; int j = 0; string myString = ""; int counter = 0; int detCounter = 0; myString = Console.ReadLine(); string[] countStr = new string[myString.Length]; int[] countArr = new int[myString.Length]; Console.Write("Enter minimum word length:"); detCounter = int.Parse(Console.ReadLine()); for (i = 0; i < myString.Length; i++) { if (myString[i] != ' ') { counter++; countStr[j] += myString[i]; } else { countArr[j] = counter; counter = 0; j++; } } if (i == myString.Length) { countArr[j] = counter; } for (i = 0; i < myString.Length ; i++) { if (detCounter <= countArr[i]) { Console.WriteLine(countStr[i]); } } Console.ReadLine(); } } }

  Read the article

• Client-side user custom CSS single file for overriding multiple domains

  - by Cawas

  This is for using in Safari, though it could probably be used on Firefox as well. In Chrome you have to add a plugin anyway (which generally allow for custom CSS per domain), and Opera already allows this to be done without needing any CSS. But while it's for customizing on the client-side, it's also a pure CSS question. So I'm using no plugins here. So, again, I got a custom CSS code (easily) working for all domains. Now I want to get specify CSS code for each domain. All with just 1 CSS file that's being loaded by Safari. Over the web and googling, I've found two ways to supposedly do this, but none actually worked. They're both documented on userstyles.com: @-moz-document domain("your-domain.com") { }. This would be perfect, since I can have several tags like that and just choose which style will be loaded for which domain. It just doesn't work. @namespace is quite confusing and I've tried every variation I could think of. None worked.

  Read the article

• C++ STL question related to insert iterators and sets

  - by rshepherd

  #include #include #include #include using namespace std; class MyContainer { public: string value; MyContainer& operator=(const string& s) { this->value = s; return *this; } }; int main() { list<string> strings; strings.push_back("0"); strings.push_back("1"); strings.push_back("2"); set<MyContainer> containers; copy(strings.begin(), strings.end(), inserter(containers, containers.end())); } The preceeding code does not compile. In typical STL style the error output is verbose and difficult to understand. The key part seems to be this... /usr/include/c++/4.4/bits/stl_algobase.h:313: error: no match for ‘operator=’ in ‘__result.std::insert_iterator::operator* [with _Container = std::set, std::allocator ]() = __first.std::_List_iterator::operator* [with _Tp = std::basic_string, std::allocator ]()’ ...which I interpet to mean that the assignment operator needed is not defined. I took a look at the source code for insert_iterator and noted that it has overloaded the assignment operator. The copy algorithm must uses the insert iterators overloaded assignment operator to do its work(?). I guess that because my input iterator is on a container of strings and my output iterator is on a container of MyContainers that the overloaded insert_iterator assignment operator can no longer work. This is my best guess, but I am probably wrong. So, why exactly does this not work and how can I accomplish what I am trying to do?

  Read the article

• How to correctly pass a float from C# to C++ (dll)

  - by RavelT

  I'm getting huge differences when I pass a float from C# to C++. I'm passing a dynamic float wich changes over time. With a debuger I get this: c++ lonVel -0.036019072 float c# lonVel -0.029392920 float I did set my MSVC++2010 floating point model to /fp:fast wich should be the standard in .NET if I'm not mistaken, but this didnt help. Now I cant give out the code but I can show a fraction of it. From C# side it looks like this: namespace Example { public class Wheel { public bool loging = true; #region Members public IntPtr nativeWheelObject; #endregion Members public Wheel() { this.nativeWheelObject = Sim.Dll_Wheel_Add(); return; } #region Wrapper methods public void SetVelocity(float lonRoadVelocity,float latRoadVelocity){Sim.Dll_Wheel_SetVelocity(this.nativeWheelObject,lonRoadVelocity,latRoadVelocity);} #endregion Wrapper methods } internal class Sim { #region PInvokes [DllImport(pluginName, CallingConvention=CallingConvention.Cdecl)] public static extern void Dll_Wheel_SetVelocity(IntPtr wheel,float lonRoadVelocity,float latRoadVelocity); #endregion PInvokes } } And in C++ side @ exportFunctions.cpp: EXPORT_API void Dll_Wheel_SetVelocity(CarWheel* wheel,float lonRoadVelocity,float latRoadVelocity){ wheel->SetVelocity(lonRoadVelocity,latRoadVelocity);} So any sugestions on what I should do in order to get 1:1 results or atleast 99% correct results.

  Read the article

• fgets throwing unhandled exception while parsing stl

  - by user3478400

  I am new to c++, I am trying to parse a stl file which is of about 64MB and has about ~18K lines in it. The code works fine for first few 100 lines but then fgets throws following exception: "Unhandled exception at 0x77B0BAC5 (ntdll.dll) in STLparser.exe: 0xC0000024: There is a mismatch between the type of object required by the requested operation and the type of object that is specified in the request." I have checked manually the line for which fgets throws exception, there is nothing out of ordinary there. I am out of options for now. Any help to fix this issue will be greatly appreciated. ================CODE========================== #include<fstream> #include<iostream> #include"ParseString.h" #include"Vectors.h" using namespace std; int main(void) { //Define variables FILE *file; char *line = new char; parsestring oneline; int n_Vols = 0, n_Elms = 0, n_nods = -1, E = 0; Nod *nodes = new Nod(); Nod dummy; Elm *elements = new Elm(); int mycounter = 0; //Open file fopen_s(&file, "sample.stl", "r"); while (fgets(line, 1024, file) != NULL) //**********Getting Error Here************* { // populate required data } fclose(file); printf("%d,%d,%d", n_Vols, n_Elms, n_nods); getchar(); return 0; } ===================When broken, execution resumes at this function (not my function, something internal) void __cdecl _unlock ( int locknum ) { /* * leave the critical section. */ LeaveCriticalSection( _locktable[locknum].lock ); }

  Read the article

• in haskell, why do I need to specify type constraints, why can't the compiler figure them out?

  - by Steve

  Consider the function, add a b = a + b This works: *Main> add 1 2 3 However, if I add a type signature specifying that I want to add things of the same type: add :: a -> a -> a add a b = a + b I get an error: test.hs:3:10: Could not deduce (Num a) from the context () arising from a use of `+' at test.hs:3:10-14 Possible fix: add (Num a) to the context of the type signature for `add' In the expression: a + b In the definition of `add': add a b = a + b So GHC clearly can deduce that I need the Num type constraint, since it just told me: add :: Num a => a -> a -> a add a b = a + b Works. Why does GHC require me to add the type constraint? If I'm doing generic programming, why can't it just work for anything that knows how to use the + operator? In C++ template programming, you can do this easily: #include <string> #include <cstdio> using namespace std; template<typename T> T add(T a, T b) { return a + b; } int main() { printf("%d, %f, %s\n", add(1, 2), add(1.0, 3.4), add(string("foo"), string("bar")).c_str()); return 0; } The compiler figures out the types of the arguments to add and generates a version of the function for that type. There seems to be a fundamental difference in Haskell's approach, can you describe it, and discuss the trade-offs? It seems to me like it would be resolved if GHC simply filled in the type constraint for me, since it obviously decided it was needed. Still, why the type constraint at all? Why not just compile successfully as long as the function is only used in a valid context where the arguments are in Num? Thank you.

  Read the article

• Mathmatic errors in basic C++ program

  - by Heather

  I am working with a basic C++ program to determine the area and perimeter of a rectangle. My program works fine for whole numbers but falls apart when I use any number with a decimal. I get the impression that I am leaving something out, but since I'm a complete beginner, I have no idea what. Below is the source: #include <iostream> using namespace std; int main() { // Declared variables int length; // declares variable for length int width; // declares variable for width int area; // declares variable for area int perimeter; // declares variable for perimeter // Statements cout << "Enter the length and the width of the rectangle: "; // states what information to enter cin >> length >> width; // user input of length and width cout << endl; // closes the input area = length * width; // calculates area of rectangle perimeter = 2 * (length + width); //calculates perimeter of rectangle cout << "The area of the rectangle = " << area << " square units." <<endl; // displays the calculation of the area cout << "The perimeter of the rectangle = " << perimeter << " units." << endl; // displays the calculation of the perimeter system ("pause"); // REMOVE BEFORE RELEASE - testing purposes only return 0; }

  Read the article

< Previous Page | 135 136 137 138 139 140 141 142 143 144 145 146  | Next Page >