Search Results

Search found 21759 results on 871 pages for 'int 0'.

Page 418/871 | < Previous Page | 414 415 416 417 418 419 420 421 422 423 424 425  | Next Page >

• Why does C++ allow variable length arrays that aren't dynamically allocated?

  - by Maulrus

  I'm relatively new to C++, and from the beginning it's been drilled into me that you can't do something like int x; cin >> x; int array[x]; Instead, you must use dynamic memory. However, I recently discovered that the above will compile (though I get a -pedantic warning saying it's forbidden by ISO C++). I know that it's obviously a bad idea to do it if it's not allowed by the standard, but I previously didn't even know this was possible. My question is, why does g++ allow variable length arrays that aren't dynamically allocated if it's not allowed by the standard? Also, if it's possible for the compiler to do it, why isn't it in the standard?

  Read the article

• Simple, Custom Parsing with c++

  - by bradkovach

  Hi! I have been reading SO for some time now, but I truly cannot find any help for my problem. I have a c++ assignment to create an IAS simulator. Here is some sample code... 0 1 a 1 2 b 2 c 3 1 10 begin 11 . load a, subtract b and offset by -1 for jump+ 11 load M(0) 12 sub M(1) 13 sub M(3) 14 halt Using c++, I need to be able to read these lines and store them in a "memory register" class that I already have constructed... For example, the first line would need to store "1 a" in register zero. How can I parse out the number at the line beginning and then store the rest as a string? I have setup storage using a class that is called using mem.set(int, string);. int is the memory location at the beginning of the line and string is the stored instruction.

  Read the article

• There is more then one Point class

  - by Dmitry

  Today I hit something very annoying while working with one of my colleagues. It seems there are two Point classes in .NET and by mistake we were trying for a good few minutes to figure out why our "Point(x,y)" wouldn’t take double, but only Int. Turns out we were using the wrong one since the XAML element in question needed the version with Double. So, based on what you actually want to do, make sure you’re using the right namespace. Please see below for MSDN reference links for each namespace version of Point, hope this saves you some time. System.Windows Point (MSDN Ref - Double version) System.Dawing Point (MSDN Ref - Int version)

  Read the article

• How do you extract data from a Date/Time widget from a C++ MFC dialog in VS2008

  - by jkerian

  This is a fairly basic question, but I haven't been able to find any from-to guides from VS6-VS2008. I have a dialog box that contains controls of various types, I've discovered the way of auto-generating OnBnClickedMyFooBarButtonHere() methods via the Properties dialog on the dialog editor. I can also use CWnd::GetDlgItemText(int ,CString &) to extract text, and the oddly paramaterized GetDlgItemInt(int, bool*, bool) to extract signed integers, but is there really no other option for a Date or Time value other than Manually adding in all the DDX_ crap that the class wizard used to do in VS6 Using GetDlgItemText and then parsing whatever it gives me?

  Read the article

• Is it a good or bad practice to call instance methods from a java constructor?

  - by Steve

  There are several different ways I can initialize complex objects (with injected dependencies and required set-up of injected members), are all seem reasonable, but have various advantages and disadvantages. I'll give a concrete example: final class MyClass { private final Dependency dependency; @Inject public MyClass(Dependency dependency) { this.dependency = dependency; dependency.addHandler(new Handler() { @Override void handle(int foo) { MyClass.this.doSomething(foo); } }); doSomething(0); } private void doSomething(int foo) { dependency.doSomethingElse(foo+1); } } As you can see, the constructor does 3 things, including calling an instance method. I've been told that calling instance methods from a constructor is unsafe because it circumvents the compiler's checks for uninitialized members. I.e. I could have called doSomething(0) before setting this.dependency, which would have compiled but not worked. What is the best way to refactor this? Make doSomething static and pass in the dependency explicitly? In my actual case I have three instance methods and three member fields that all depend on one another, so this seems like a lot of extra boilerplate to make all three of these static. Move the addHandler and doSomething into an @Inject public void init() method. While use with Guice will be transparent, it requires any manual construction to be sure to call init() or else the object won't be fully-functional if someone forgets. Also, this exposes more of the API, both of which seem like bad ideas. Wrap a nested class to keep the dependency to make sure it behaves properly without exposing additional API:class DependencyManager { private final Dependency dependency; public DependecyManager(Dependency dependency) { ... } public doSomething(int foo) { ... } } @Inject public MyClass(Dependency dependency) { DependencyManager manager = new DependencyManager(dependency); manager.doSomething(0); } This pulls instance methods out of all constructors, but generates an extra layer of classes, and when I already had inner and anonymous classes (e.g. that handler) it can become confusing - when I tried this I was told to move the DependencyManager to a separate file, which is also distasteful because it's now multiple files to do a single thing. So what is the preferred way to deal with this sort of situation?

  Read the article

• How do I tell Entity Framework that a column in a view is nullable?

  - by Ryan ONeill

  I have a view which has an Int column which is nullable (let's call it StackOverflowCount). When generating an EF model from the database, the EF designer does not recognise it as nullable and creates the column as an Int. The issue I have is that on the EF designer I have set the column to Nullable and the following error then kills the compilation; Error 3031: Problem in mapping fragments starting at line 2327: Non-nullable column MyView.StackOverflowCount in table MyView is mapped to a nullable entity property. I can get round this by opening the .edmx file in XML mode and manually editing the SQL column definition, but there is no way to do this using the designer and it gets overwritten the next time I refresh from the model from the DB. Is this 'by design' or an example of something that slipped through into EF 4.0? I'm using .Net 4.0 with EF 4.0 under VS 2010.

  Read the article

• ASP.MVC ModelBinding Behaviour

  - by OldBoy

  This one has me stumped, despite the numerous posts on here. The scenario is a basic MVC(2) web application with simple CRUD operations. Whenever the edit form is submitted and the UpdateModel() called, an exception is thrown: System.Data.Linq.ForeignKeyReferenceAlreadyHasValueException was unhandled by user code This occurs against a DropDownList value which is a foreign key on the entity table. However, there is another DropDownList list on the form, representing another foreign key, which does not throw the error (unsurprisingly). Changing the property values manually inside the Edit Action: Recipe recipe = repository.GetRecipe(int.Parse(formValues["recipeid"])); recipe.CategoryId = Convert.ToInt32(formValues["CategoryId"].ToString()); recipe.Page = int.Parse(formValues["Page"].ToString()); recipe.PublicationId=Convert.ToInt32(formValues["PublicationId"].ToString()); Allows the CategoryId and Page properties to be updated, and then the error is thrown on the PublicationId. All of the referential integrity is checked an the same in the db and the dbml. Any light shed on this would be most welcome.

  Read the article

• How can I link two Java serialised objects back together?

  - by Kidburla

  Sometimes (quite a lot, actually) we get a situation in Java where two objects are pointing to the same thing. Now if we serialise these separately it is quite appropriate that the serialised forms have separate copies of the object as it should be possible to open one without the other. However if we now deserialise them both, we find that they are still separated. Is there any way to link them back together? Example follows. public class Example { private static class ContainerClass implements java.io.Serializable { private ReferencedClass obj; public ReferencedClass get() { return obj; } public void set(ReferencedClass obj) { this.obj = obj; } } private static class ReferencedClass implements java.io.Serializable { private int i = 0; public int get() { return i; } public void set(int i) { this.i = i; } } public static void main(String[] args) throws Exception { //Initialise the classes ContainerClass test1 = new ContainerClass(); ContainerClass test2 = new ContainerClass(); ReferencedClass ref = new ReferencedClass(); //Make both container class point to the same reference test1.set(ref); test2.set(ref); //This does what we expect: setting the integer in one (way of accessing the) referenced class sets it in the other one test1.get().set(1234); System.out.println(Integer.toString(test2.get().get())); //Now serialise the container classes java.io.ObjectOutputStream os = new java.io.ObjectOutputStream(new java.io.FileOutputStream("C:\\Users\\Public\\test1.ser")); os.writeObject(test1); os.close(); os = new java.io.ObjectOutputStream(new java.io.FileOutputStream("C:\\Users\\Public\\test2.ser")); os.writeObject(test2); os.close(); //And deserialise them java.io.ObjectInputStream is = new java.io.ObjectInputStream(new java.io.FileInputStream("C:\\Users\\Public\\test1.ser")); ContainerClass test3 = (ContainerClass)is.readObject(); is.close(); is = new java.io.ObjectInputStream(new java.io.FileInputStream("C:\\Users\\Public\\test2.ser")); ContainerClass test4 = (ContainerClass)is.readObject(); is.close(); //We expect the same thing as before, and would expect a result of 4321, but this doesn't happen as the referenced objects are now separate instances test3.get().set(4321); System.out.println(Integer.toString(test4.get().get())); } }

  Read the article

• Scala, make my loop more functional

  - by Pengin

  I'm trying to reduce the extent to which I write Scala (2.8) like Java. Here's a simplification of a problem I came across. Can you suggest improvements on my solutions that are "more functional"? Transform the map val inputMap = mutable.LinkedHashMap(1->'a',2->'a',3->'b',4->'z',5->'c') by discarding any entries with value 'z' and indexing the characters as they are encountered First try var outputMap = new mutable.HashMap[Char,Int]() var counter = 0 for(kvp <- inputMap){ val character = kvp._2 if(character !='z' && !outputMap.contains(character)){ outputMap += (character -> counter) counter += 1 } } Second try (not much better, but uses an immutable map and a 'foreach') var outputMap = new immutable.HashMap[Char,Int]() var counter = 0 inputMap.foreach{ case(number,character) => { if(character !='z' && !outputMap.contains(character)){ outputMap2 += (character -> counter) counter += 1 } } }

  Read the article

• Incompatible format types

  - by nebffa

  I'm playing around with strncpy in C and am having some trouble. The code is as follows: #include <stdio.h> #include <string.h> int main(int argc, char *argv[]) { char src[] = "Benjamin Franklin"; char dest[5]; strncpy(src, dest, sizeof(dest) / sizeof(char)); dest[5] = '\0'; printf("%s\n", dest); return 0; } which compiles with no errors using: gcc -Wall -g -Werror test.c -o test and prints out gibberish like p4?? I cannot really understand what I'm doing wrong especially since I have played around with it a lot and been looking online for answers. Perhaps since I am using arrays I am passing the address to printf without realising it?

  Read the article

• Efficient retrieval of lists over WebServices

  - by Chris

  I have a WCF WebService that uses LINQ and EF to connect to an SQL database. I have an ASP.NET MVC front end that collects its data from the webservice. It currently has functions such as List<Customer> GetCustomers(); As the number of customers increases massively the amount of data being passed increases also reducing efficiency. What is the best way to "page data" across WebServices etc. My current idea is to implement a crude paging system such as List<Customer> GetCustomers(int start, int length); This, however, means I would have to replicate such code for all functions returning List types. It is unfortunate that I cannot use LINQ as it would be much nicer. Does anyone have any advice or ideas of patterns to implement that would be "as nice as possible" Thanks

  Read the article

• Specializing a template member function of a template class?

  - by uj2

  I have a template class that has a template member function that needs to be specialized, as in: template <typename T> class X { public: template <typename U> void Y() {} template <> void Y<int>() {} }; Altough VC handles this correctly, apperantly this isn't standard and GCC complains: explicit specialization in non-namespace scope 'class X<T>' I tried: template <typename T> class X { public: template <typename U> void Y() {} }; template <typename T> // Also tried `template<>` here void X<T>::Y<int>() {} But this causes both VC and GCC to complain. What's the right way to do this?

  Read the article

• How to compile using gcc but without using _alloca ?

  - by shkim

  For some reason, I should use gcc to compile a C file, then link against Visual C++ 2008 project. (I used the current latest gcc version: cygwin gcc 4.3.4 20090804.) But there is one problem: gcc always allocate a big array with _alloca, and VC linker can't resolve the symbol __alloca. for example, int func() { int big[10240]; .... } this code makes the _alloca dependency although I didn't call the _alloca function explicitly. (array size matters. if i change 10240 - 128, everything ok) I tried gcc option -fno-builtin-alloca or -fno-builtin, but no luck. Is it possible to make gcc not to use _alloca ? (or adjust the threshold?)

  Read the article

• C++ String pointers

  - by gnm

  In my previous app I had an object like this: class myType { public: int a; string b; } It had a lot of instances scattered everywhere and passed around to nearly every function. The app was slow. Profiling said that 95% of time is eaten by the string allocator function. I know how to work with the object above, but not how to work with string pointers. class myType { public: int a; string* b; } They told me to use pointers as above. How much faster is it with a string pointer? What is copied when I copy the object? How to the following using the class with the pointer: Access the string value Modify the string value without modifying the one in the object (copy?) General things that change if I use string pointers?

  Read the article

• How can I obtain the IP address of my server program?

  - by Dr Dork

  Hello! This question is related to another question I just posted. I'm prepping for a simple work project and am trying to familiarize myself with the basics of socket programming in a Unix dev environment. At this point, I have some basic server side code and client side code setup to communicate. Currently, my client code successfully connects to the server code and the server code sends it a test message, then both quit out. Perfect! That's exactly what I wanted to accomplish. Now I'm playing around with the functions used to obtain info about the two environments (server and client). I'd like to obtain my server program's IP address. Here's the code I currently have to do this, but it's not working... int sockfd; unsigned int len; socklen_t sin_size; char msg[]="test message"; char buf[MAXLEN]; int st, rv; struct addrinfo hints, *serverinfo, *p; struct sockaddr_storage client; char s[INET6_ADDRSTRLEN]; char ip[INET6_ADDRSTRLEN]; //zero struct memset(&hints,0,sizeof(hints)); hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_PASSIVE; //get the server info if((rv = getaddrinfo(NULL, SERVERPORT, &hints, &serverinfo ) != 0)){ perror("getaddrinfo"); exit(-1); } // loop through all the results and bind to the first we can for( p = serverinfo; p != NULL; p = p->ai_next) { //Setup the socket if( (sockfd = socket( p->ai_family, p->ai_socktype, p->ai_protocol )) == -1 ) { perror("socket"); continue; } //Associate a socket id with an address to which other processes can connect if(bind(sockfd, p->ai_addr, p->ai_addrlen) == -1){ close(sockfd); perror("bind"); continue; } break; } if( p == NULL ){ perror("Fail to bind"); } inet_ntop(p->ai_family, get_in_addr((struct sockaddr *)p->ai_addr), s, sizeof(s)); printf("Server has TCP Port %s and IP Address %s\n", SERVERPORT, s); and the output for the IP is always empty... server has TCP Port 21412 and IP Address :: any ideas for what I'm missing? thanks in advance for your help! this stuff is really complicated at first.

  Read the article

• How to return a copy of the data in C++

  - by Josh Curren

  I am trying to return a new copy of the data in a C++ Template class. The following code is getting this error: invalid conversion from ‘int*’ to ‘int’. If I remove the new T then I am not returning a copy of the data but a pointer to it. template<class T> T OrderedList<T>::get( int k ) { Node<T>* n = list; for( int i = 0; i < k; i++ ) { n=n->get_link(); } return new T( n->get_data() ); // This line is getting the error ********** }

  Read the article

• What is problem with below class

  - by user258367

  class LinkedList { private: int data; LinkedList *ptr; public: LinkedList(int i_data) { data = i_data; ptr = 0; { ~LinkedList() { delete ptr ; } void insert(LinkedList *node) { while(this->next != 0) this = this->next; this->next = node; } I will be creating a head node like head = new LinkedList(4) and then will be calling like head->insert(new LinkedList(5)) and subsequently . Can you please tell me does above class represent a linkedlist . i think yes it has node which contain address of next node . Please correct me if i am wrong

  Read the article

• Get Dataset returned from an ajax enabled wcf service....

  - by Pandiya Chendur

  I call an ajax enabled wcf service method , <script type="text/javascript"> function GetEmployee() { Service.GetEmployeeData('1','5',onGetDataSuccess); } function onGetDataSuccess(result) { Iteratejsondata(result) } </script> and my method is , [OperationContract] public string GetEmployeeData(int currentPage,int pageSize) { DataSet ds = GetEmployeeViewData(currentPage,pageSize); return GetJSONString(ds.Tables[0]); } My Dataset ds contains three datatable but i am using the first one for my records... Other two datatables have values how can i get them in result... function onGetDataSuccess(result) { Iteratejsondata(result) } Any suggestion...

  Read the article

• Unity 2D Instantiating a prefab with it's components

  - by TazmanNZL

  I have some block prefabs that I add to an array of game objects: public GameObject[]blocks; Each prefab has a BoxCollider2D, Script & Rigidbody2D components. But when I try to instantiate the prefab in the scene it doesn't appear to have the components attached? Here is how I am instantiating the prefab: for (int i = 0; i < 4; i++) { for (int j = 0; j < gridWidth; j++) { blockClone = Instantiate (blocks [Random.Range (0, blocks.Length)] as GameObject, new Vector3 (j, -i-2, 0f), transform.rotation) as GameObject; } } What am I doing wrong?

  Read the article

• Contacts activity doesn't return data

  - by Mike

  In my app I simply open the list of activities and when a contact is clicked I attempt to retrieve the name of the contact selected and put it into a string. The app crashes in the onActivityResult() function. I do have the READ_CONTACTS permission set. /** * Opens the contacts activity */ public void openContacts() { Intent intent = new Intent(Intent.ACTION_PICK, People.CONTENT_URI); startActivityForResult(intent, PICK_CONTACT); } @Override public void onActivityResult(int reqCode, int resultCode, Intent data) { super.onActivityResult(reqCode, resultCode, data); switch (reqCode) { case (PICK_CONTACT) : if (resultCode == Activity.RESULT_OK) { Uri contactData = data.getData(); Cursor c = managedQuery(contactData, null, null, null, null); //NullPointerException thrown here, line 102 if (c.moveToFirst()) { String name = c.getString(c.getColumnIndexOrThrow(People.NAME)); FRIEND_NAME = name; showConfirmDialog(name); } } break; } } The following logcat error logs are returned: Any help is appreciated. Thanks

  Read the article

• Infinite gtk warnings when I right click on the icon

  - by Runner

  From this tuto: #include <gtk/gtk.h> int main( int argc, char *argv[]) { GtkWidget *window; gtk_init(&argc, &argv); window = gtk_window_new(GTK_WINDOW_TOPLEVEL); gtk_widget_show(window); gtk_main(); return 0; } I run the executable and right click on the icon,then infinite warnings(the same) reported: GLib-WARNING **: g_main_context_check() called recursively from within a source's check() or prepare() member. Anyone knows how to fix this warning?

  Read the article

• How do game trainers change an address in memory that's dynamic?

  - by GameTrainersWTF

  Lets assume I am a game and I have a global int* that contains my health. A game trainer's job is to modify this value to whatever in order to achieve god mode. I've looked up tutorials on game trainers to understand how they work, and the general idea is to use a memory scanner to try and find the address of a certain value. Then modify this address by injecting a dll or whatever. But I made a simple program with a global int* and its address changes every time I run the app, so I don't get how game trainers can hard code these addresses? Or is my example wrong? What am I missing?

  Read the article

• Haskell, list of natural number

  - by Hellnar

  Hello, I am an absolute newbie in Haskell yet trying to understand how it works. I want to write my own lazy list of integers such as [1,2,3,4,5...]. For list of ones I have written ones = 1 : ones and when tried, works fine: *Main> take 10 ones [1,1,1,1,1,1,1,1,1,1] How can I do the same for increasing integers ? I have tried this but it indeed fails: int = 1 : head[ int + 1] And after that how can I make a method that multiplies two streams? such as: mulstream s1 s2 = head[s1] * head[s2] : mulstream [tail s1] [tail s2]

  Read the article

• Recursively determine average value

  - by theva

  I have to calculate an average value of my simulation. The simulation is ongoing and I want (for each iteration) to print the current average value. How do I do that? I tried the code below (in the loop), but I do not think that the right value is calculated... int average = 0; int newValue; // Continuously updated value. if(average == 0) { average = newValue; } average = (average + newValue)/2; I also taught about store each newValue in an array and for each iteration summarize the whole array and do the calculation. However, I don't think that's a good solution, because the loop is an infinity loop so I can't really determine the size of the array. There is also a possibility that I am thinking too much and that the code above is actually correct, but I don't think so...

  Read the article

• Determine an object's class returned by a factory method (Error: function does not take 1 arguments

  - by tzippy

  I have a factorymethod that either returns an object of baseclass or one that is of derivedclass (a derived class of baseclass). The derived class has a method virtual void foo(int x) that takes one argument. baseclass however has virtual void foo() without an argument. In my code, a factory method returns a pointer of type bar that definetly points to an object of class derivedclass. However since this is only known at runtime I get a compiler error saying that foo() does not take an argument. Can I cast this pointer to a pointer of type derivedclass? std::auto_ptr<baseclass> bar = classfactory::CreateBar(); //returns object of class derivedclass bar->foo(5); class baseclass { public: virtual void foo(); } class derivedclass : public baseclass { public: virtual void foo(int x); }

  Read the article

< Previous Page | 414 415 416 417 418 419 420 421 422 423 424 425  | Next Page >