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  • A Null Reference Exception

    - by Alex
    "Object reference not set to an instance of an object." using System; using System.Collections.Generic; using System.Linq; using System.Text; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.Graphics; namespace XNAdev { class Sprite { //The size of the Sprite public Rectangle Size; //Used to size the Sprite up or down from the original image public float Scale = 1.0f; //The current position of the Sprite public Vector2 Position = new Vector2(115, 0); //The texture object used when drawing the sprite private Texture2D mSpriteTexture; //Load the texture for the sprite using the Content Pipeline public void LoadContent(ContentManager theContentManager, string theAssetName) { mSpriteTexture = theContentManager.Load<Texture2D>(theAssetName); Size = new Rectangle(0, 0, (int)(mSpriteTexture.Width * Scale), (int)(mSpriteTexture.Height * Scale)); } //Draw the sprite to the screen public void Draw(SpriteBatch theSpriteBatch) { theSpriteBatch.Draw(mSpriteTexture, Position, new Rectangle(0, 0, mSpriteTexture.Width, mSpriteTexture.Height), Color.White, 0.0f, Vector2.Zero, Scale, SpriteEffects.None, 0); } } } I am very new at this C# so any help would be great. I have no idea what my error is.

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  • Const Discards Qualifers: C++

    - by user991673
    I'm using OpenGL to render camera perspectives, and a one point in my code I'm trying to take the direction of the light (shown here as type "Vector4") and multiply it by a matrix of type "Matrix4x4" that represents the Modelview transformation (sorry if this is not making any sense, this is for a school project, as such I'm still learning about this stuff) Anyway, my code goes as follows... Vector4 lightDirection = data->dir * follow->getModelviewMatrix().getInverse().getTranspose(); data->dir = lightDirection; setLight(*data); this give me the following error: passing 'const vec4<double>' as 'this' argument of 'vec4<T>& vec4<T>::operator=(const vec4<T>&)[with T = double]' discards qualifiers Again, much of this code is prewritten for the class (namely the vector and matrix types) but if someone could just help me decipher what the error means it would be much appreciated! I can give more information as needed. I figured 'data' or 'data-dir' were const, however I can find no mention of either of them to be. 'dir' is of type SceneLightData, and when its added on I'm doing this: void Scene::addLight(const SceneLightData &sceneLight) { SceneLightData light = sceneLight; m_lights.push_back(&light); } The error occurs on this line: data->dir = lightDirection; EDIT problem solved. thanks everyone! solution: void Scene::addLight(const SceneLightData &sceneLight) { SceneLightData* light = new SceneLightData; *light = sceneLight; m_lights.push_back(light); } and SceneLightData* data = m_lights[i]; data->dir = data->dir * follow->getModelviewMatrix().getInverse().getTranspose(); setLight(*data);

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  • LINQ to SQL Queries odd Materialization

    - by ptoinson
    I ran across an interesting Linq to SQL, uh, feature, the other day. Perhaps someone can give me a logical explanation for the reasoning behind the results. Take the code below as my example which utilizes the AdventureWorks database setup in a Linq to SQL DataContext. This is a clip from my unit test. The resulting customer returned from a call to both CustomerQuery_Test_01() and CustomerQuery_Test_02() is the same. However, the query executed on the SQLServer are different is a major way. The method CustomerQuery_Test_01 us causing the entire Customer table to be materialized, which the call to CustomerQuery_Test_02 is only causing the single customer to be materialized. The resulting SQL Queries are at the bottom of this post. Anyone have a good reason for this? To me, it was highly non-intuitive. protected virtual Customer GetByPrimaryKey(Func<Customer, bool> keySelection) { AdventureWorksDataContext context = new AdventureWorksDataContext(); return (from r in context.Customers select r).SingleOrDefault(keySelection); } [TestMethod] public void CustomerQuery_Test_01() { Customer customer = GetByPrimaryKey(c => c.CustomerID == 2); } [TestMethod] public void CustomerQuery_Test_02() { AdventureWorksDataContext context = new AdventureWorksDataContext(); Customer customer = (from r in context.Customers select r).SingleOrDefault(c => c.CustomerID == 2); } Query for CustomerQuery_Test_01 (notice the lack of a where clause) SELECT [t0].[CustomerID], [t0].[NameStyle], [t0].[Title], [t0].[FirstName], [t0].[MiddleName], [t0].[LastName], [t0].[Suffix], [t0].[CompanyName], [t0].[SalesPerson], [t0].[EmailAddress], [t0].[Phone], [t0].[PasswordHash], [t0].[PasswordSalt], [t0].[rowguid], [t0].[ModifiedDate] FROM [SalesLT].[Customer] AS [t0] Query for CustomerQuery_Test_02 (notice the where clause) SELECT [t0].[CustomerID], [t0].[NameStyle], [t0].[Title], [t0].[FirstName], [t0].[MiddleName], [t0].[LastName], [t0].[Suffix], [t0].[CompanyName], [t0].[SalesPerson], [t0].[EmailAddress], [t0].[Phone], [t0].[PasswordHash], [t0].[PasswordSalt], [t0].[rowguid], [t0].[ModifiedDate] FROM [SalesLT].[Customer] AS [t0] WHERE [t0].[CustomerID] = @p0

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  • Using abstract base to implement private parts of a template class?

    - by StackedCrooked
    When using templates to implement mix-ins (as an alternative to multiple inheritance) there is the problem that all code must be in the header file. I'm thinking of using an abstract base class to get around that problem. Here's a code sample: class Widget { public: virtual ~Widget() {} }; // Abstract base class allows to put code in .cpp file. class AbstractDrawable { public: virtual ~AbstractDrawable() = 0; virtual void draw(); virtual int getMinimumSize() const; }; // Drawable mix-in template<class T> class Drawable : public T, public AbstractDrawable { public: virtual ~Drawable() {} virtual void draw() { AbstractDrawable::draw(); } virtual int getMinimumSize() const { return AbstractDrawable::getMinimumSize(); } }; class Image : public Drawable< Widget > { }; int main() { Image i; i.draw(); return 0; } Has anyone walked that road before? Are there any pitfalls that I should be aware of?

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  • Editable CATextLayer?

    - by Ron
    I have several CATextLayers. When I doubleclick one of them, I want to be able to edit it's string. Think of text as it's handled in Keynote or many other apps. Any ideas? I thought of putting an editable textfield right in front of the layer and then dismiss it on enter, but I didn't get far. :-( I target Mac OS X 10.5 with Objective-C 2.0 and Garbage Collection. Any help or pointers would be greatly appreciated. Thanks in advance!!

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  • C# object (2 numbers) performing 2 calculations

    - by Chris
    I have a couple questions about creating a object (2 values) and how to "call" it. Initializing the object with: Tweetal t1, t2, t3, t4, t5, t6; t1 = new Tweetal(); //a: 0 , b = 0 t2 = new Tweetal(-2); //a: -2, b = -2 t3 = new Tweetal(5, 17); //a: 5, b = 17 t4 = new Tweetal(t3); //a:5, b = 17 Console.Write("t1 = " + t1); Console.Write("\tt2 = " + t2); Console.Write("\tt3 = " + t3); Console.Write("\tt4 = " + t4); Console.WriteLine("\n"); t1 = t1.Som(t2); t4 = t2.Som(t2); //...... Now the 2 things i want to do with this object are taking the SUM and the SUMNumber: Sum: t4 = t2.sum(t3); (this would result in t4: a:3 (-2+5), b: 15(-2+17) SumNumber: t1 = t3.sum(8) (this would result in t1: a:13 , b:25) Next is my code for the object (in a separate class), but how exactly do i perform the simple sum calculation when i call up for example t2 etc... public class Tweetal: Object { private int a; private int b; public Tweetal() { //??? //Sum(...,...) } public Tweetal(int a) { //??? //Sum(...,...) } public Tweetal(int a, int b) { //??? } public Tweetal(Tweetal //....) // to call upton the object if i request t1, t2, t3,... insteed of a direct number value) { // ???? } public void Sum(int aValue, int bValue) { //a = ??? //b = ??? //Sum(...,...) } public void SumNumber(int aValue, int bValue) { } public override string ToString() { return string.Format("({0}, {1})", a, b); }/*ToString*/ }

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  • How can i initialise a server on startup?

    - by djerry
    Hey all, I need to make some connections on startup of a server. I'm using the wcf technology for this client-server application. The problem is that the constructor of the server isn't called at any time, so for the moment, i initialize the connections when the first client makes a connection. But this generates problems in a further part. This is my server setup: private static ServiceHost _svc; static void Main(string[] args) { NetTcpBinding binding = new NetTcpBinding(SecurityMode.Message); Uri address = new Uri("net.tcp://localhost:8000"); _svc = new ServiceHost(typeof(MonitoringSystemService), address); publishMetaData(_svc, "http://localhost:8001"); _svc.AddServiceEndpoint(typeof(IMonitoringSystemService), binding, "Monitoring Server"); _svc.Open(); Console.WriteLine("Listener service gestart op net.tcp://localhost:8000/Monitoring"); Console.ReadLine(); } private static void publishMetaData(ServiceHost svc, string sEndpointAddress) { ServiceMetadataBehavior smb = svc.Description.Behaviors.Find<ServiceMetadataBehavior>(); if (smb != null) { smb.HttpGetEnabled = true; smb.HttpGetUrl = new Uri(sEndpointAddress); } else { smb = new ServiceMetadataBehavior(); smb.HttpGetEnabled = true; smb.HttpGetUrl = new Uri(sEndpointAddress); svc.Description.Behaviors.Add(smb); } } How can i start the server without waiting for a client to logon so i can initialize it. Thanks in advance.

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  • Call instance method with objc_msgSend

    - by user772349
    I'm trying to use the objc_msgSend method to call some method dynamically. Say I want call some method in Class B from Class A and there are two methods in class B like: - (void) instanceTestWithStr1:(NSString *)str1 str2:(NSString *)str1; + (void) methodTestWithStr1:(NSString *)str1 str2:(NSString *)str1; And I can call the class method like this in Class A successfully: objc_msgSend(objc_getClass("ClassB"), sel_registerName("methodTestWithStr1:str2:"), @"111", @"222"); And I can call the instance method like this in Class A successfully as well: objc_msgSend([[objc_getClass("ClassB") alloc] init], sel_registerName("instanceTestWithStr1:str2:"), @"111", @"222"); But the thing is to get a instance of Class B I have to call "initWithXXXXX:XXXXXX:XXXXXX" instead of "init" so that to pass some necessary parameters to class B to do the init stuff. So I stored a instance of ClassB in class A as variable: self.classBInstance = [[ClassB alloc] initWithXXXXX:XXXXXX:XXXXXX]; And then I call the method like this (successfully): The problem is, I want to call a method by simply applying the classname and the method sel like "ClassName" and "SEL" and then call it dynamically: If it's a class method. then call it like: objc_msgSend(objc_getClass("ClassName"), sel_registerName("SEL")); If it's a instance method, find the existing class instance variable in the calling class then: objc_msgSend([self.classInstance, sel_registerName("SEL")); So I want to know if there is any way to: Check if a class has a given method (I found "responseToSelector" will be the one) Check if a given method in class method or instance method (maybe can use responseToSelector as well) Check if a class has a instance variable of a given class So I can call a instance method like: objc_msgSend(objc_getClassInstance(self, "ClassB"), sel_registerName("SEL"));

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  • Java constructor using generic types

    - by user37903
    I'm having a hard time wrapping my head around Java generic types. Here's a simple piece of code that in my mind should work, but I'm obviously doing something wrong. Eclipse reports this error in BreweryList.java: The method initBreweryFromObject() is undefined for the type <T> The idea is to fill a Vector with instances of objects that are a subclass of the Brewery class, so the invocation would be something like: BreweryList breweryList = new BreweryList(BrewerySubClass.class, list); BreweryList.java package com.beerme.test; import java.util.Vector; public class BreweryList<T extends Brewery> extends Vector<T> { public BreweryList(Class<T> c, Object[] j) { super(); for (int i = 0; i < j.length; i++) { T item = c.newInstance(); // initBreweryFromObject() is an instance method // of Brewery, of which <T> is a subclass (right?) c.initBreweryFromObject(); // "The method initBreweryFromObject() is undefined // for the type <T>" } } } Brewery.java package com.beerme.test; public class Brewery { public Brewery() { super(); } protected void breweryMethod() { } } BrewerySubClass.java package com.beerme.test; public class BrewerySubClass extends Brewery { public BrewerySubClass() { super(); } public void androidMethod() { } } I'm sure this is a complete-generics-noob question, but I'm stuck. Thanks for any tips!

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  • Optimization of a c++ matrix/bitmap class

    - by Andrew
    I am searching a 2D matrix (or bitmap) class which is flexible but also fast element access. The contents A flexible class should allow you to choose dimensions during runtime, and would look something like this (simplified): class Matrix { public: Matrix(int w, int h) : data(new int[x*y]), width(w) {} void SetElement(int x, int y, int val) { data[x+y*width] = val; } // ... private: // symbols int width; int* data; }; A faster often proposed solution using templates is (simplified): template <int W, int H> class TMatrix { TMatrix() data(new int[W*H]) {} void SetElement(int x, int y, int val) { data[x+y*W] = val; } private: int* data; }; This is faster as the width can be "inlined" in the code. The first solution does not do this. However this is not very flexible anymore, as you can't change the size anymore at runtime. So my question is: Is there a possibility to tell the compiler to generate faster code (like when using the template solution), when the size in the code is fixed and generate flexible code when its runtime dependend? I tried to achieve this by writing "const" where ever possible. I tried it with gcc and VS2005, but no success. This kind of optimization would be useful for many other similar cases.

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  • Unexpected behaviour of Process.MainWindowHandle

    - by Ed Guiness
    I've been trying to understand Process.MainWindowHandle. According to MSDN; "The main window is the window that is created when the process is started. After initialization, other windows may be opened, including the Modal and TopLevel windows, but the first window associated with the process remains the main window." (Emphasis added) But while debugging I noticed that MainWindowHandle seemed to change value... which I wasn't expecting, especially after consulting the documentation above. To confirm the behaviour I created a standalone WinForms app with a timer to check the MainWindowHandle of the "DEVENV" (Visual Studio) process every 100ms. Here's the interesting part of this test app... IntPtr oldHWnd = IntPtr.Zero; void GetMainwindowHandle() { Process[] processes = Process.GetProcessesByName("DEVENV"); if (processes.Length!=1) return; IntPtr newHWnd = processes[0].MainWindowHandle; if (newHWnd != oldHWnd) { oldHWnd = newHWnd; textBox1.AppendText(processes[0].MainWindowHandle.ToString("X")+"\r\n"); } } private void timer1Tick(object sender, EventArgs e) { GetMainwindowHandle(); } You can see the value of MainWindowHandle changing when you (for example) click on a drop-down menu inside VS. Perhaps I've misunderstood the documentation. Can anyone shed light?

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  • Asynchronous Controller is blocking requests in ASP.NET MVC through jQuery

    - by Jason
    I have just started using the AsyncController in my project to take care of some long-running reports. Seemed ideal at the time since I could kick off the report and then perform a few other actions while waiting for it to come back and populate elements on the screen. My controller looks a bit like this. I tried to use a thread to perform the long task which I'd hoped would free up the controller to take more requests: public class ReportsController : AsyncController { public void LongRunningActionAsync() { AsyncManager.OutstandingOperations.Increment(); var newThread = new Thread(LongTask); newThread.Start(); } private void LongTask() { // Do something that takes a really long time //....... AsyncManager.OutstandingOperations.Decrement(); } public ActionResult LongRunningActionCompleted(string message) { // Set some data up on the view or something... return View(); } public JsonResult AnotherControllerAction() { // Do a quick task... return Json("..."); } } But what I am finding is that when I call LongRunningAction using the jQuery ajax request, any further requests I make after that back up behind it and are not processed until LongRunningAction completes. For example, call LongRunningAction which takes 10 seconds and then call AnotherControllerAction which is less than a second. AnotherControllerAction simply waits until LongRunningAction completes before returning a result. I've also checked the jQuery code, but this still happens if I specifically set "async: true": $.ajax({ async: true, type: "POST", url: "/Reports.aspx/LongRunningAction", dataType: "html", success: function(data, textStatus, XMLHttpRequest) { // ... }, error: function(XMLHttpRequest, textStatus, errorThrown) { // ... } }); At the moment I just have to assume that I'm using it incorrectly, but I'm hoping one of you guys can clear my mental block!

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  • HTML reuse, create template

    - by nanonerd
    After about a year doing Asp.net web forms, I stepped out (for the most part) from the .net world. I'm now working on a webapp that uses a lot of client side scripting and uses WebAPI for data access. I have a HTML section that allows note taking. I would like to make this HTML section into a template that I can reuse elsewhere on the site (e.g., insert this piece of HTML code into another web page). I'm a bit befuddled on how to go about this. Think of my problem as trying to create a "user control" in asp.net web forms ... only that I am not using web forms. Just good old fashioned HTML, CSS, Javascript, jquery, and knockout. Conceptually, I'd think that others have been in the same spot as myself. Can anyone elaborate a solution or at least provide some pointers? Thanks !

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  • java threads don't see shared boolean changes

    - by andymur
    Here the code class Aux implements Runnable { private Boolean isOn = false; private String statusMessage; private final Object lock; public Aux(String message, Object lock) { this.lock = lock; this.statusMessage = message; } @Override public void run() { for (;;) { synchronized (lock) { if (isOn && "left".equals(this.statusMessage)) { isOn = false; System.out.println(statusMessage); } else if (!isOn && "right".equals(this.statusMessage)) { isOn = true; System.out.println(statusMessage); } if ("left".equals(this.statusMessage)) { System.out.println("left " + isOn); } } } } } public class Question { public static void main(String [] args) { Object lock = new Object(); new Thread(new Aux("left", lock)).start(); new Thread(new Aux("right", lock)).start(); } } In this code I expect to see: left, right, left right and so on, but when Thread with "left" message changes isOn to false, Thread with "right" message don't see it and I get ("right true" and "left false" console messages), left thread don't get isOn in true, but right Thread can't change it cause it always see old isOn value (true). When i add volatile modifier to isOn nothing changes, but if I change isOn to some class with boolean field and change this field then threads are see changes and it works fine Thanks in advance.

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  • better understanding of getline() and cin

    - by numerical25
    Trying to get some basic understanding of console functionalities. I am having issues so consider the following... #include "stdafx.h" #include<iostream> #include<conio.h> using namespace std; /* This is a template Project */ void MultiplicationTable(int x); int main() { int value = 0; printf("Please enter any number \n\n"); getline(cin, value); MultiplicationTable(value); getchar(); return 0; } I actually based this off code from http://www.cplusplus.com/doc/tutorial/basic_io/ . My IDE is not recognizing getline() so of course when I compile the application. I get an error 'getline': identifier not found Now take a look at this code #include "stdafx.h" #include<iostream> #include<conio.h> using namespace std; /* This is a template Project */ void MultiplicationTable(int x); int main() { int value = 0; printf("Please enter any number \n\n"); cin>>value; MultiplicationTable(value); getchar(); return 0; } When I execute this line of code the console window opens and immediately closes. I think I a missing something about cin. I do know that it delimits spaces but I don't know what else. what should I use for input to make my life easier.

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  • Styled Javascript Popup that Conncects to Database

    - by user269799
    I want to create a javascript popup box that contains text fields. I want to be able to style this box - using CSS - and I want the textfield entries to be Inserted into a MySQL database. Is this possible? I would be familiar with doing this through web forms and server side scripting but I need it to be a bit more client side this time to make things seem a bit faster. I am thinking I may need to learn some AJAX but any pointers would be a help. GF

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  • Detecting crosses in an image

    - by MrOrdinaire
    I am working on a program to detect the tips of a probing device and analyze the color change during probing. The input/output mechanisms are more or less in place. What I need now is the actual meat of the thing: detecting the tips. In the images below, the tips are at the center of the crosses. I thought of applying BFS to the images after some threshold'ing but was then stuck and didn't know how to proceed. I then turned to OpenCV after reading that it offers feature detection in images. However, I am overwhelmed by the vast amount of concepts and techniques utilized here and again, clueless about how to proceed. Am I looking at it the right way? Can you give me some pointers? Image extracted from short video Binary version with threshold set at 95

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  • Combining packages from different projects into a single project in eclipse

    - by primal
    Hi, As part of the Android application I am developing in eclipse, I need to combine two packages from different projects into a single project. I tried copying the files in the package of the second project under the src folder of the first folder and copied other files required for second package into the res folder of the first project. But the auto-generated Java files i.e R.java doesn't get updated on copying. I tried right clicking on the project and clicking on Android Tools - Fix Project Properties. But nothing changed. Any pointers on what I am doing wrong much be appreciated.

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  • Merging and splitting overlapping rectangles to produce non-overlapping ones

    - by uj
    I am looking for an algorithm as follows: Given a set of possibly overlapping rectangles (All of which are "not rotated", can be uniformly represented as (left,top,right,bottom) tuplets, etc...), it returns a minimal set of (non-rotated) non-overlapping rectangles, that occupy the same area. It seems simple enough at first glance, but prooves to be tricky (at least to be done efficiently). Are there some known methods for this/ideas/pointers? Methods for not necessarily minimal, but heuristicly small, sets, are interesting as well, so are methods that produce any valid output set at all.

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  • How to change size of STL container in C++

    - by Jaime Pardos
    I have a piece of performance critical code written with pointers and dynamic memory. I would like to rewrite it with STL containers, but I'm a bit concerned with performance. Is there a way to increase the size of a container without initializing the data? For example, instead of doing ptr = new BYTE[x]; I want to do something like vec.insert(vec.begin(), x, 0); However this initializes every byte to 0. Isn't there a way to just make the vector grow? I know about reserve() but it just allocates memory, it doesn't change the size of the vector, and doesn't allows me to access it until I have inserted valid data. Thank you everyone.

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  • java.lang.NoClassDefFoundError when the file is there

    - by tsOverflow
    I've tried to look around for postings that might help me, cant find any. I am deploying an ear to JBoss4 server, and I started having this problem since I added a new project. this new project is defined as Java project in eclipse, and the EAR project has an EJB project that has the new Java project as one of the projects as its dependent upon - if deployed on JBoss locally through eclipse, there's no problem and everything goes smoothly But when being deployed to JBoss in test environment (outside eclipse), kept getting java.lang.NoClassDefFoundError on one of the classes that are defined in the new Java project. I looked inside the EAR file to get to the jar (EJB project), and then inside the jar, I can see the directory structure and all the class files from the new Java project - ie. The class that it complains about is right there inside the EAR-JAR and matching the exact structure that it's looking for. I am at lost to what else I can look at. Any pointers are greatly appreciated! Thanks

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  • Is there a way of getting a file name and inserting into Matlab script?

    - by torr
    In a folder, I have both my .m file that contains the script and an imaging .dcm file that needs to be analyzed. Folder structure: Folder1/analysis.m Folder1/meas_dynamic_123.dcm My script (analysis.m) begins as follows: target =''; <== here should go the full path to the file + filename example: /Volumes/Data/Folder1/meas_dynamic_123.m txt = dir(target); // etc So I'm wondering if there is a way of when running analysis.m it will: automatically search the folder it's in, grab the full path + filename of file containing string dynamic in the name, insert its full path + name into target variable continue running the script Does anyone have any pointers on how to achieve this? Using ffpath?

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  • operator overloading and inheritance

    - by user168715
    I was given the following code: class FibHeapNode { //... // These all have trivial implementation virtual void operator =(FibHeapNode& RHS); virtual int operator ==(FibHeapNode& RHS); virtual int operator <(FibHeapNode& RHS); }; class Event : public FibHeapNode { // These have nontrivial implementation virtual void operator=(FibHeapNode& RHS); virtual int operator==(FibHeapNode& RHS); virtual int operator<(FibHeapNode& RHS); }; class FibHeap { //... int DecreaseKey(FibHeapNode *theNode, FibHeapNode& NewKey) { FibHeapNode *theParent; // Some code if (theParent != NULL && *theNode < *theParent) { //... } //... return 1; } }; Much of FibHeap's implementation is similar: FibHeapNode pointers are dereferenced and then compared. Why does this code work? (or is it buggy?) I would think that the virtuals here would have no effect: since *theNode and *theParent aren't pointer or reference types, no dynamic dispatch occurs and FibHeapNode::operator< gets called no matter what's written in Event.

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  • WPF: issue updating UI from background thread

    - by Ted Shaffer
    My code launches a background thread. The background thread makes changes and wants the UI in the main thread to update. The code that launches the thread then waits looks something like: Thread fThread = new Thread(new ThreadStart(PerformSync)); fThread.IsBackground = true; fThread.Start(); fThread.Join(); MessageBox.Show("Synchronization complete"); When the background wants to update the UI, it sets a StatusMessage and calls the code below: static StatusMessage _statusMessage; public delegate void AddStatusDelegate(); private void AddStatus() { AddStatusDelegate methodForUIThread = delegate { _statusMessageList.Add(_statusMessage); }; this.Dispatcher.BeginInvoke(methodForUIThread, System.Windows.Threading.DispatcherPriority.Send); } _statusMessageList is an ObservableCollection that is the source for a ListBox. The AddStatus method is called but the code on the main thread never executes - that is, _statusMessage is not added to _statusMessageList while the thread is executing. However, once it is complete (fThread.Join() returns), all the stacked up calls on the main thread are executed. But, if I display a message box between the calls to fThread.Start() and fThread.Join(), then the status messages are updated properly. What do I need to change so that the code in the main thread executes (UI updates) while waiting for the thread to terminate? Thanks.

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  • Data structure name: combination array/linked list

    - by me_and
    I have come up with a data structure that combines some of the advantages of linked lists with some of the advantages of fixed-size arrays. It seems very obvious to me, and so I'd expect someone to have thought of it and named it already. Does anyone know what this is called: Take a small fixed-size array. If the number of elements you want to put in your array is greater than the size of the array, add a new array and whatever pointers you like between the old and the new. Thus you have: Static array ————————————————————————— |1|2|3|4|5|6|7|8|9|a|b|c| ————————————————————————— Linked list ———— ———— ———— ———— ———— |1|*->|2|*->|3|*->|4|*->|5|*->NULL ———— ———— ———— ———— ———— My thing: ———————————— ———————————— |1|2|3|4|5|*->|6|7|8|9|a|*->NULL ———————————— ————————————

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