Search Results

Search found 14661 results on 587 pages for 'static discharge'.

Page 223/587 | < Previous Page | 219 220 221 222 223 224 225 226 227 228 229 230  | Next Page >

  • OOP C# Question: Making a Fruit a Pear

    - by Adam Kane
    Given that I have an instance of Fruit with some properties set, and I want to get those properties into a new Pear instance (because this particular Fruit happens to have the qualities of a pear), what's the best way to achieve this effect? For example, what we can't do is simple cast a Fruit to a Pear, because not all Fruits are Pears: public static class PearGenerator { public static Pear CreatePear () { // Make a new generic fruit. Fruit genericFruit = new Fruit(); // Upcast it to a pear. (Throws exception: Can't cast a Fruit to a Pear.) Pear pear = (Pear)genericFruit; // Return freshly grown pear. return ( pear ); } } public class Fruit { // some code } public class Pear : Fruit { public void PutInPie () { // some code } } Thanks! Update: I don't control the "new Fruit()" code. My starting point is that I've got a Fruit to work with. I need to get that Fruit into a new Pear somehow. Maybe copy all the properties one by one?

    Read the article

  • Error while reading custom configuration file(app.config)

    - by Newbie
    I am making a custom configuration in my winform application. (It will represent a country-corrency list) First the CountryList class namespace UtilityMethods { public class CountryList : ConfigurationSection { public CountryList() { // // TODO: Add constructor logic here // } [ConfigurationProperty("CountryCurrency", IsRequired = true)] public Hashtable CountryCurrencies { get { return CountryCurrency.GetCountryCurrency(); } } } } The GetCountryCurrency() method is defined in CountryCurrency class as under namespace UtilityMethods { public static class CountryCurrency { public static Hashtable GetCountryCurrency() { Hashtable ht = new Hashtable(); ht.Add("India", "Rupees"); ht.Add("USA", "Dollar"); return ht; } } } The app.config file looks like <?xml version="1.0" encoding="utf-8" ?> <configuration> <configSections> <section name ="CountryList1" type ="UtilityMethods.CountryList,CountryList,Version=2.0.0.0, Culture=neutral"/> </configSections> <appSettings /> </configuration> And I am calling this from a button_click's event as try { CountryList cList = ConfigurationManager.GetSection("CountryList") as CountryList; Hashtable ht = cList.CountryCurrencies; } catch (Exception ex) { string h = ex.Message; } Upon running the application and clicking on the button I am getting this error Could not load type 'UtilityMethods.CountryList' from assembly 'System.Configuration, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' Please help (dotnet framework : 3.5 Language: C#)

    Read the article

  • Hibernate Transient Extends problem

    - by mrvreddy
    @MappedSuperclass public abstract class BaseAbstract implements Serializable{ private static final long serialVersionUID = 1L; protected String test = //some random value; public String getTest() { return test; } public void setTest(String test){ this.test = test; } } @Entity public class Artist extends BaseAbstract { private static final long serialVersionUID = 1L; private Integer id; @override @Transient public String getTest() { return test; } ..... } My question is... when i am trying to do any operation on the artist, along with id and name, test is also getting saved which should not be the case... if i add the same transient on the baseabstract class getTest() method, i see test column NOT getting created(ideally what it should happen) but if i try to override the method with adding annotaion in the sub class it creates the test column... I dont know why this is happening since when hibernate is creating the artist object and checks for annotations, it should see the transient annotation present on the getTest() of artist method...and should not create a column in the database... Let me know if you need any clarification.... Any response on this is greatly appreciated.... Thank you

    Read the article

  • Why I'm not getting "Multiple definition" error from the g++?

    - by ban
    I tried to link my executable program with 2 static libraries using g++. The 2 static libraries have the same function name. I'm expecting a "multiple definition" linking error from the linker, but I did not received. Can anyone help to explain why is this so? staticLibA.h #ifndef _STATIC_LIBA_HEADER #define _STATIC_LIBA_HEADER int hello(void); #endif staticLibA.cpp #include "staticLibA.h" int hello(void) { printf("\nI'm in staticLibA\n"); return 0; } output: g++ -c -Wall -fPIC -m32 -o staticLibA.o staticLibA.cpp ar -cvq ../libstaticLibA.a staticLibA.o a - staticLibA.o staticLibB.h #ifndef _STATIC_LIBB_HEADER #define _STATIC_LIBB_HEADER int hello(void); #endif staticLibB.cpp #include "staticLibB.h" int hello(void) { printf("\nI'm in staticLibB\n"); return 0; } output: g++ -c -Wall -fPIC -m32 -o staticLibB.o staticLibB.cpp ar -cvq ../libstaticLibB.a staticLibB.o a - staticLibB.o main.cpp extern int hello(void); int main(void) { hello(); return 0; } output: g++ -c -o main.o main.cpp g++ -o multipleLibsTest main.o -L. -lstaticLibA -lstaticLibB -lstaticLibC -ldl -lpthread -lrt

    Read the article

  • Weird compile-time behavior when trying to use primitive type in generics

    - by polygenelubricants
    import java.lang.reflect.Array; public class PrimitiveArrayGeneric { static <T> T[] genericArrayNewInstance(Class<T> componentType) { return (T[]) Array.newInstance(componentType, 0); } public static void main(String args[]) { int[] intArray; Integer[] integerArray; intArray = (int[]) Array.newInstance(int.class, 0); // Okay! integerArray = genericArrayNewInstance(Integer.class); // Okay! intArray = genericArrayNewInstance(int.class); // Compile time error: // cannot convert from Integer[] to int[] integerArray = genericArrayNewInstance(int.class); // Run time error: // ClassCastException: [I cannot be cast to [Ljava.lang.Object; } } I'm trying to fully understand how generics works in Java. Things get a bit weird for me in the 3rd assignment in the above snippet: the compiler is complaining that Integer[] cannot be converted to int[]. The statement is 100% true, of course, but I'm wondering WHY the compiler is making this complaint. If you comment that line, and follow the compiler's "suggestion" as in the 4th assignment, the compiler is actually satisfied!!! NOW the code compiles just fine! Which is crazy, of course, since like the run time behavior suggests, int[] cannot be converted to Object[] (which is what T[] is type-erased into at run time). So my question is: why is the compiler "suggesting" that I assign to Integer[] instead for the 3rd assignment? How does the compiler reason to arrive to that (erroneous!) conclusion?

    Read the article

  • [java] Returning the element number of the longest string in an array

    - by JohnRoberts
    Hoookay, so. I'm trying to get the longestS method to take the user-inputted array of strings, then return the element number of the longest string in that array. I got it to the point where I was able to return the number of chars in the longest string, but I don't believe that will work for what I need. My problem is that I keep getting incompatible type errors when trying to figure this out. I don't understand the whole data type thing with strings yet. It's confusing me how I go about return a number of the array yet the array is of strings. The main method is fine, I got stuck on the ???? part. { public static void main(String [] args) { Scanner inp = new Scanner( System.in ); String [] responseArr= new String[4]; for (int i=0; i<4; i++) { System.out.println("Enter string "+(i+1)); responseArr[i] = inp.nextLine(); } int highest=longestS(responseArr); } public static int longestS(String[] values) { int largest=0 for( int i = 1; i < values.length; i++ ) { if ( ????? ) } return largest; } }

    Read the article

  • How does one force construction of a global object in a statically linked library? [MSVC9]

    - by Peter C O Johansson
    I have a global list of function pointers. This list should be populated at startup. Order is not important and there are no dependencies that would complicate static initialization. To facilitate this, I've written a class that adds a single entry to this list in its constructor, and scatter global instances of this class via a macro where necessary. One of the primary goals of this approach is to remove the need for explicitly referencing every instance of this class externally, instead allowing each file that needs to register something in the list to do it independently. Nice and clean. However, when placing these objects in a static library, the linker discards (or rather never links in) these units because no code in them is explicitly referenced. Explicitly referencing symbols in the compilation units would be counterproductive, directly contradicting one of the main goals of the approach. For the same reason, /INCLUDE is not an acceptable option, and /OPT:NOREF is not actually related to this problem. Metrowerks has a __declspec directive for it, GCC has -force_load, but I cannot find any equivalent for MSVC.

    Read the article

  • How to allow all except part 1 and part 2 ?

    - by Stackfan
    This allows me to get easyly dynamic input variables instead of putting a static prefix like /en/etcetcetc, but the problem is all controllers are blocked. Everything goes to index/index. Question: How can i tell this rule allow evertying as it is now, but do not track if it contains http://site.com/donotcatch/me and http://site.com/iamnotbelongstodynamic1/blabla protected function _initRoutes() { ... $dynamic1 = new Zend_Controller_Router_Route( '/:variable0/:variable1', array( 'controller' => 'index', 'action' => 'index'), array( 'variable0' => '^[a-zA-Z0-9_]*$', 'variable1' => '^[a-zA-Z0-9_]*$', ) ); Follow up: Normally, i always belive yes we can, so, we can do that like this where dynamic1 does not the inter-fare with my other static controllers: // http://site/yeswecan/blabla // variable0 = yeswecan // variable1 = blabla $dynamic1 = new Zend_Controller_Router_Route( '/:variable0/:variable1', array( 'controller' => 'index', 'action' => 'index'), array( 'variable0' => '^[a-zA-Z]*$', 'variable1' => '^[a-z0-9_]*$', ) ); // http://site/ajax/whatever... // solves it $dynamic2 = new Zend_Controller_Router_Route( '/ajax/:variable0', array( 'controller' => 'ajax', 'action' => '' ), array( 'variable0' => '^[a-zA-Z0-9_]*$', ) ); // http://site/order/whatever... // solves it $dynamic3 = new Zend_Controller_Router_Route( '/order/:variable0', array( 'controller' => 'order', 'action' => ''), array( 'variable0' => '^[a-zA-Z0-9_]*$', ) ); Note: Still the controllers are getting failed for example http://site/ajax/whatever always goes to /ajax/index where i wanted to send it as /ajax/user-inserted-value How can i fix the $dynamic2 and $dynamic3 by keeping $dynamic1 ??

    Read the article

  • Problem with generic list and extension method(C#3.0)

    - by Newbie
    I have an issue. I am making an extension class for a Collection and it is generic.. like public static class ListExtensions { public static ICollection<T> Search<T>(this ICollection<T> collection, string stringToSearch) { ICollection<T> t1=null; foreach (T t in collection) { Type k = t.GetType(); PropertyInfo pi = k.GetProperty("Name"); if (pi.GetValue(t,null).Equals(stringToSearch)) { t1.Add(t); } } return t1; } } But I cannot add items to t1 as it is declared null. Error: object reference not set to an instance of the object. I am calling the method like List<TestClass> listTC = new List<TestClass>(); listTC.Add(new TestClass { Name = "Ishu", Age = 21 }); listTC.Add(new TestClass { Name = "Vivek", Age = 40 }); listTC.Add(new TestClass { Name = "some one else", Age = 12 }); listTC.Search("Ishu"); And the test class is public class TestClass { public string Name { get; set; } public int Age { get; set; } } Using : (C#3.0) & Framework - 3.5 Thanks

    Read the article

  • Why isn't our c# graphics code working any more?

    - by Jared
    Here's the situation: We have some generic graphics code that we use for one of our projects. After doing some clean-up of the code, it seems like something isn't working anymore (The graphics output looks completely wrong). I ran a diff against the last version of the code that gave the correct output, and it looks like we changed one of our functions as follows: static public Rectangle FitRectangleOld(Rectangle rect, Size targetSize) { if (rect.Width <= 0 || rect.Height <= 0) { rect.Width = targetSize.Width; rect.Height = targetSize.Height; } else if (targetSize.Width * rect.Height > rect.Width * targetSize.Height) { rect.Width = rect.Width * targetSize.Height / rect.Height; rect.Height = targetSize.Height; } else { rect.Height = rect.Height * targetSize.Width / rect.Width; rect.Width = targetSize.Width; } return rect; } to static public Rectangle FitRectangle(Rectangle rect, Size targetSize) { if (rect.Width <= 0 || rect.Height <= 0) { rect.Width = targetSize.Width; rect.Height = targetSize.Height; } else if (targetSize.Width * rect.Height > rect.Width * targetSize.Height) { rect.Width *= targetSize.Height / rect.Height; rect.Height = targetSize.Height; } else { rect.Height *= targetSize.Width / rect.Width; rect.Width = targetSize.Width; } return rect; } All of our unit tests are all passing, and nothing in the code has changed except for some syntactic shortcuts. But like I said, the output is wrong. We'll probably just revert back to the old code, but I'm curious if anyone has any idea what's going on here. Thanks.

    Read the article

  • pthread_join from a signal handler

    - by liv2hak
    I have a capture program which in addition do capturing data and writing it into a file also prints some statistics.The function that prints the statistics static void* report(void) { /*Print statistics*/ } is called roughly every second using an ALARM that expires every second.So The program is like void capture_program() { pthread_t report_thread while(!exit_now) { if(pthread_create(&report_thread,NULL,report,NULL)){ fprintf(stderr,"Error creating reporting thread! \n"); } /* Capturing code -------------- -------------- */ if(doreport) usleep(5); } } void *report(void *param) { while(true) { if(doreport) { doreport = 0 //access some register from hardware usleep(5) } } } The expiry of the timer sets the doreport flag.If this flag is set report() is called which clears the flag.I am using usleep to alternate between two threads in the program.This seems to work fine. I also have a signal handler to handle SIGINT (i.e CTRL+C) static void anysig(int sig) { if (sig != SIGINT) dagutil_set_signal_handler(SIG_DFL); /* Tell the main loop to exit */ exit_now = 1; return; } My question: 1) Is it safe to call pthread_join from inside the signal handler? 2) Should I use exit_now flag for the report thread as well?

    Read the article

  • What was your "aha moment" in understanding delegates?

    - by CM90
    Considering the use of delegates in C#, does anyone know if there is a performance advantage or if it is a convenience to the programmer? If we are creating an object that holds a method, it sounds as if that object would be a constant in memory to be called on, instead of loading the method every time it is called. For example, if we look at the following Unity3D-based code: public delegate H MixedTypeDelegate<G, H>(G g) public class MainParent : MonoBehaviour // Most Unity classes inherit from M.B. { public static Vector3 getPosition(GameObject g) { /* GameObject is a Unity class, and Vector3 is a struct from M.B. The "position" component of a GameObject is a Vector3. This method takes the GameObject I pass to it & returns its position. */ return g.transform.position; } public static MixedTypeDelegate<GameObject, Vector3> PositionOf; void Awake( ) // Awake is the first method called in Unity, always. { PositionOf = MixedTypeDelegate<GameObject, Vector3>(getPosition); } } public class GameScript : MainParent { GameObject g = new GameObject( ); Vector3 whereAmI; void Update( ) { // Now I can say: whereAmI = PositionOf(g); // Instead of: whereAmI = getPosition(g); } } . . . But that seems like an extra step - unless there's that extra little thing that it helps. I suppose the most succinct way to ask a second question would be to say: When you had your aha moment in understanding delegates, what was the context/scenario/source? Thank you!

    Read the article

  • Need help extrapolating Java code

    - by Berlioz
    If anyone familiar with Rebecca Wirfs-Brock, she has a piece of Java code found in her book titled, Object Design: Roles, Responsibilities, and Collaborations. Here is the quote Applying Double Dispatch to a Specific Problem To implement the game Rock, Paper, Scissors we need to write code that determines whether one object “beats” another. The game has nine possible outcomes based on the three kinds of objects. The number of interactions is the cross product of the kinds of objects. Case or switch statements are often governed by the type of data that is being operated on. The object-oriented language equivalent is to base its actions on the class of some other object. In Java, it looks like this Here is the piece of Java code on page 16 ' import java.util.*; import java.lang.*; public class Rock { public static void main(String args[]) { } public static boolean beats(GameObject object) { if (object.getClass.getName().equals("Rock")) { result = false; } else if (object.getClass.getName().equals("Paper")) { result = false; } else if(object.getClass.getName().equals("Scissors")) { result = true; } return result; } }' ===This is not a very good solution. First, the receiver needs to know too much about the argument. Second, there is one of these nested conditional statements in each of the three classes. If new kinds of objects could be added to the game, each of the three classes would have to be modified. Can anyone share with me how to get this "less than optimal" piece of code to work in order to see it 'working'. She proceeds to demonstrate a better way, but I will spare you. Thanks

    Read the article

  • ASP.NET MVC twitter/myspace style routing

    - by Astrofaes
    Hi guys, This is my first post after being a long-time lurker - so please be gentle :-) I have a website similar to twitter, in that people can sign up and choose a 'friendly url', so on my site they would have something like: mydomain.com/benjones I also have root level static pages such as: mydomain.com/about and of course my homepage: mydomain.com/ I'm new to ASP.NET MVC 2 (in fact I just started today) and I've set up the following routes to try and achieve the above. public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.IgnoreRoute("content/{*pathInfo}"); routes.IgnoreRoute("images/{*pathInfo}"); routes.MapRoute("About", "about", new { controller = "Common", action = "About" } ); // User profile sits at root level so check for this before displaying the homepage routes.MapRoute("UserProfile", "{url}", new { controller = "User", action = "Profile", url = "" } ); routes.MapRoute("Home", "", new { controller = "Home", action = "Index", id = "" } ); } For the most part this works fine, however, my homepage is not being triggered! Essentially, when you browser to mydomain.com, it seems to trigger the User Profile route with an empty {url} parameter and so the homepage is never reached! Any ideas on how I can show the homepage?

    Read the article

  • OOP/MVC advice on where to place a global helper function

    - by franko75
    Hi, I have a couple of controllers on my site which are handling form data. The forms use AJAX and I have quite a few methods across different controllers which are having to do some specific processing to return errors in a JSON encoded format - see code below. Obviously this isn't DRY and I need to move this code into a single helper function which I can use globally, but I'm wondering where this should actually go! Should I create a static helper class which contains this function (e.g Validation::build_ajax_errors()), or as this code is producing a format which is application specific and tied into the jQuery validation plugin I'm using, should it be a static method stored in, for example, my main Website controller which the form handling controllers extend from? //if ajax request, output errors if (request::is_ajax()) { //need to build errors into array form for javascript validation - move this into a helper method accessible globally $errors = $post->errors('form_data/form_error_messages'); $i = 0; $new_errors = array(); foreach ($errors as $key => $value) { $new_errors[$i][0] = '#' . $key; $new_errors[$i][1] = $value; $new_errors[$i][2] = "error"; $i++; } echo '{"jsonValidateReturn":' . json_encode($new_errors) . '}'; return; }

    Read the article

  • I can not get the text from a selected item in a listview...pleeeeasss help.

    - by Miguel
    I always get an ClassCastException error... i do not what else to do... - I'm using a data biding concept to populated the listview from a sqlite3 database. - I just want to get the selected item text after a long press click. This is the code of the activity: public class ItemConsultaGastos extends ListActivity { private DataHelper dh ; TextView seleccion; private static String[] FROM = {DataHelper.MES, DataHelper.ANO}; private static int[] TO = {R.id.columnaMes, R.id.columnaAno }; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.muestrafechas); this.dh = new DataHelper(this); Cursor cursor = dh.selectAllMeses(); startManagingCursor(cursor); this.mostrarFechas(cursor); ListView lv = getListView(); lv.setOnItemLongClickListener(new OnItemLongClickListener(){ @Override public boolean onItemLongClick(AdapterView<?> arg0, View arg1,int row, long arg3) { //here is where i got the classCastException. String[] tmp = (String[]) arg0.getItemAtPosition(row); //tmp[0] ist the Text of the first TextView displayed by the clicked ListItem Log.w("Gastos: ", "El texto: " + tmp[0].toString()); return true; } }); } private void mostrarFechas(Cursor cursor) { SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,R.layout.muestrafechasitem,cursor, FROM, TO); setListAdapter(adapter); } } ///// This is the xml where a define the rows to show on the listview <TextView android:id="@+id/espacio" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=" " /> <TextView android:id="@+id/columnaAno" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="20sp" android:layout_toRightOf="@+id/espacio"/> <TextView android:id="@+id/separador1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text=" -- " android:layout_toRightOf="@+id/columnaAno" android:textSize="20sp" /> <TextView android:id="@+id/columnaMes" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_toRightOf="@+id/separador1" android:textSize="20sp"/>

    Read the article

  • Failed to create a 'System.Windows.RoutedEventHandler' from the text 'Button_Click'

    - by ay89
    In my windows phone 8 application, while trying to create a dependency property I am always getting this exception. what I am doing wrong, plz guide me. {System.Windows.Markup.XamlParseException: Failed to create a 'System.Windows.RoutedEventHandler' from the text 'Button_Click'. [Line: 108 Position: 66] at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator) at com.sap.View.HomePage.InitializeComponent() at com.sap.View.HomePage..ctor()} this is code-behind of Header public static readonly DependencyProperty MenuClickProperty = DependencyProperty.Register("MenuClick", typeof(RoutedEventHandler), typeof(Header), new PropertyMetadata(OnMenuClickHandlerChanged)); public RoutedEventHandler MenuClick { get { return (RoutedEventHandler)GetValue(MenuClickProperty); } set { SetValue(MenuClickProperty, new RoutedEventHandler(value)); } } private static void OnMenuClickHandlerChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { Header header = d as Header; header.OnMenuClickHandlerPropertyChanged(e); } private void OnMenuClickHandlerPropertyChanged(DependencyPropertyChangedEventArgs e) { MenuButton.Click += MenuClick; } this is in my user control (Header) <Button Click="{Binding Path=MenuClick, Source={RelativeSource Mode=Self}}" /> this is how i am including control on my Page: <myControls:Header Title="{Binding Title}" MenuClick="Button_Click" /> this is in code-behind: public void Button_Click(object sender, RoutedEventArgs e) { OpenSettings(); }

    Read the article

  • Best way to run multiple queries per second on database, performance wise?

    - by Michael Joell
    I am currently using Java to insert and update data multiple times per second. Never having used databases with Java, I am not sure what is required, and how to get the best performance. I currently have a method for each type of query I need to do (for example, update a row in a database). I also have a method to create the database connection. Below is my simplified code. public static void addOneForUserInChannel(String channel, String username) throws SQLException { Connection dbConnection = null; PreparedStatement ps = null; String updateSQL = "UPDATE " + channel + "_count SET messages = messages + 1 WHERE username = ?"; try { dbConnection = getDBConnection(); ps = dbConnection.prepareStatement(updateSQL); ps.setString(1, username); ps.executeUpdate(); } catch(SQLException e) { System.out.println(e.getMessage()); } finally { if(ps != null) { ps.close(); } if(dbConnection != null) { dbConnection.close(); } } } And my DB connection private static Connection getDBConnection() { Connection dbConnection = null; try { Class.forName(DB_DRIVER); } catch (ClassNotFoundException e) { System.out.println(e.getMessage()); } try { dbConnection = DriverManager.getConnection(DB_CONNECTION, DB_USER,DB_PASSWORD); return dbConnection; } catch (SQLException e) { System.out.println(e.getMessage()); } return dbConnection; } This seems to be working fine for now, with about 1-2 queries per second, but I am worried that once I expand and it is running many more, I might have some issues. My questions: Is there a way to have a persistent database connection throughout the entire run time of the process? If so, should I do this? Are there any other optimizations that I should do to help with performance? Thanks

    Read the article

  • sum of square of each elements in the vector using for_each

    - by pierr
    Hi, As the function accepted by for_each take only one parameter (the element of the vector), I have to define a static int sum = 0 somewhere so that It can be accessed after calling the for_each . I think this is awkward. Any better way to do this (still use for_each) ? #include <algorithm> #include <vector> #include <iostream> using namespace std; static int sum = 0; void add_f(int i ) { sum += i * i; } void test_using_for_each() { int arr[] = {1,2,3,4}; vector<int> a (arr ,arr + sizeof(arr)/sizeof(arr[0])); for_each( a.begin(),a.end(), add_f); cout << "sum of the square of the element is " << sum << endl; } In Ruby, We can do it this way: sum = 0 [1,2,3,4].each { |i| sum += i*i} #local variable can be used in the callback function puts sum #=> 30 Would you please show more examples how for_each is typically used in practical programming (not just print out each element)? Is it possible use for_each simulate 'programming pattern' like map and inject in Ruby (or map /fold in Haskell). #map in ruby >> [1,2,3,4].map {|i| i*i} => [1, 4, 9, 16] #inject in ruby [1, 4, 9, 16].inject(0) {|aac ,i| aac +=i} #=> 30 EDIT: Thank you all. I have learned so much from your replies. We have so many ways to do the same single thing in C++ , which makes it a little bit difficult to learn. But it's interesting :)

    Read the article

  • Translating 3-dimensional array reference onto 1-dimensional array

    - by user146780
    If there is an array of ar[5000] then how could I find where element [5][5][4] would be if this was a 3 dimensional array? Thanks I'm mapping pixels: imagine a bimap of [768 * 1024 * 4] where would pixel [5][5][4] be? I want to make this: static GLubyte checkImage[checkImageHeight][checkImageWidth][4]; static GLuint texName; bool itt; void makeCheckImage(void) { Bitmap *b = new Bitmap(L"c:/boo.png"); int i, j, c; Color cul; for (i = 0; i < checkImageHeight; i++) { for (j = 0; j < checkImageWidth; j++) { b->GetPixel(j,i,&cul); checkImage[i][j][0] = (GLubyte) cul.GetR(); checkImage[i][j][1] = (GLubyte) cul.GetG(); checkImage[i][j][2] = (GLubyte) cul.GetB(); checkImage[i][j][3] = (GLubyte) cul.GetA(); } } delete(b); } work without making a multidimensional array. width = 512, height = 1024....

    Read the article

  • GridView ObjectDataSource LINQ Paging and Sorting using multiple table query.

    - by user367426
    I am trying to create a pageing and sorting object data source that before execution returns all results, then sorts on these results before filtering and then using the take and skip methods with the aim of retrieving just a subset of results from the database (saving on database traffic). this is based on the following article: http://www.singingeels.com/Blogs/Nullable/2008/03/26/Dynamic_LINQ_OrderBy_using_String_Names.aspx Now I have managed to get this working even creating lambda expressions to reflect the sort expression returned from the grid even finding out the data type to sort for DateTime and Decimal. public static string GetReturnType<TInput>(string value) { var param = Expression.Parameter(typeof(TInput), "o"); Expression a = Expression.Property(param, "DisplayPriceType"); Expression b = Expression.Property(a, "Name"); Expression converted = Expression.Convert(Expression.Property(param, value), typeof(object)); Expression<Func<TInput, object>> mySortExpression = Expression.Lambda<Func<TInput, object>>(converted, param); UnaryExpression member = (UnaryExpression)mySortExpression.Body; return member.Operand.Type.FullName; } Now the problem I have is that many of the Queries return joined tables and I would like to sort on fields from the other tables. So when executing a query you can create a function that will assign the properties from other tables to properties created in the partial class. public static Account InitAccount(Account account) { account.CurrencyName = account.Currency.Name; account.PriceTypeName = account.DisplayPriceType.Name; return account; } So my question is, is there a way to assign the value from the joined table to the property of the current table partial class? i have tried using. from a in dc.Accounts where a.CompanyID == companyID && a.Archived == null select new { PriceTypeName = a.DisplayPriceType.Name}) but this seems to mess up my SortExpression. Any help on this would be much appreciated, I do understand that this is complex stuff.

    Read the article

  • Aligning messageformat on printing a JTable.

    - by DanielFH
    I'm using this for the moment to print out my table, and it works. But I'm not really happy with the layout of the messageformatting, I would like to have both pagenumber and date in the footer, and date format aligned to the left side of the table, and page to the right. How can I do that? Been reading some stuff about overriding the PrintTable method, but seems to get pretty complex from what I've read. Hope you can help me with this issue, thank you. :) import javax.print.attribute.HashPrintRequestAttributeSet; import javax.print.attribute.PrintRequestAttributeSet; import javax.print.attribute.standard.OrientationRequested; import javax.swing.JTable; import dk.beesys.rims.ui.WindowInventory; public class Print { private static Print INSTANCE; public static Print getInstance() { if (INSTANCE == null) { INSTANCE = new Print(); } return INSTANCE; } private Print(){ } public void printList(java.awt.event.ActionEvent ignore) { String strDate = MessageFormat.format("{0,date,short} {0,time,short}", new Date()); MessageFormat header = new MessageFormat("- {0} -"); MessageFormat footer = new MessageFormat("Printed: " + strDate); PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet(); aset.add(OrientationRequested.LANDSCAPE); try { WindowInventory.getInstance().getTable().print(JTable.PrintMode.FIT_WIDTH, header, footer, true, aset, true); } catch (java.awt.print.PrinterException e) { System.err.format("Cannot print %s%n", e.getMessage()); } }

    Read the article

  • Detect Application Shutdown in C# NET?

    - by Michael Pfiffer
    I am writing a small console application (will be ran as a service) that basically starts a Java app when it is running, shuts itself down if the Java app closes, and shuts down the Java app if it closes. I think I have the first two working properly, but I don't know how to detect when the .NET application is shutting down so that I can shutdown the Java app prior to that happening. Google search just returns a bunch of stuff about detecting Windows shutting down. Can anyone tell me how I can handle that part and if the rest looks fine? namespace MinecraftDaemon { class Program { public static void LaunchMinecraft(String file, String memoryValue) { String memParams = "-Xmx" + memoryValue + "M" + " -Xms" + memoryValue + "M "; String args = memParams + "-jar " + file + " nogui"; ProcessStartInfo processInfo = new ProcessStartInfo("java.exe", args); processInfo.CreateNoWindow = true; processInfo.UseShellExecute = false; try { using (Process minecraftProcess = Process.Start(processInfo)) { minecraftProcess.WaitForExit(); } } catch { // Log Error } } static void Main(string[] args) { Arguments CommandLine = new Arguments(args); if (CommandLine["file"] != null && CommandLine["memory"] != null) { // Launch the Application LaunchMinecraft(CommandLine["file"], CommandLine["memory"]); } else { LaunchMinecraft("minecraft_server.jar", "1024"); } } } }

    Read the article

  • Compiler turning a string& into a basic_string<>&

    - by Shtong
    Hello I'm coming back to C++ after long years spent on other technologies and i'm stuck on some weird behavior when calling some methods taking std::string as parameters : An example of call : LocalNodeConfiguration *LocalNodeConfiguration::ReadFromFile(std::string & path) { // ... throw configuration_file_error(string("Configuration file empty"), path); // ... } When I compile I get this (I cropped file names for readability) : /usr/bin/g++ -g -I/home/shtong/Dev/OmegaNoc/build -I/usr/share/include/boost-1.41.0 -o CMakeFiles/OmegaNocInternals.dir/configuration/localNodeConfiguration.cxx.o -c /home/shtong/Dev/OmegaNoc/source/configuration/localNodeConfiguration.cxx .../localNodeConfiguration.cxx: In static member function ‘static OmegaNoc::LocalNodeConfiguration* OmegaNoc::LocalNodeConfiguration::ReadFromFile(std::string&)’: .../localNodeConfiguration.cxx:72: error: no matching function for call to ‘OmegaNoc::configuration_file_error::configuration_file_error(std::string, std::basic_string<char, std::char_traits<char>, std::allocator<char> >&)’ .../configurationManager.hxx:25: note: candidates are: OmegaNoc::configuration_file_error::configuration_file_error(std::string&, std::string&) .../configurationManager.hxx:22: note: OmegaNoc::configuration_file_error::configuration_file_error(const OmegaNoc::configuration_file_error&) So as I understand it, the compiler is considering that my path parameter turned into a basic_string at some point, thus not finding the constructor overload I want to use. But I don't really get why this transformation happened. Some search on the net suggested me to use g++ but I was already using it. So any other advice would be appreciated :) Thanks

    Read the article

  • C++ socket protocol design issue (ring inclusion)

    - by Martin Lauridsen
    So I have these two classes, mpqs_client and client_protocol. The mpqs_client class handles a Boost socket connection to a server (sending and receiving messages with some specific format. Upon receiving a message, it calls a static method, parse_message(..), in the class client_protocol, and this method should analyse the message received and perform some corresponding action. Given some specific input, the parse_message method needs to send some data back to the server. As mentioned, this happens through the class mpqs_client. So I could, from mpqs_client, pass "this" to parse_message(..) in client_protocol. However, this leads to a two-way association relationship between the two classes. Something which I reckon is not desireable. Also, to implement this, I would need to include the other in each one, and this gives me a terrible pain. I am thinking this is more of a design issue. What is the best solution here? Code is posted below. Class mpqs_client: #include "mpqs_client.h" mpqs_client::mpqs_client(boost::asio::io_service& io_service, tcp::resolver::iterator endpoint_iterator) : io_service_(io_service), socket_(io_service) { ... } ... void mpqs_client::write(const network_message& msg) { io_service_.post(boost::bind(&mpqs_client::do_write, this, msg)); } Class client_protocol: #include "../network_message.hpp" #include "../protocol_consts.h" class client_protocol { public: static void parse_message(network_message& msg, mpqs_sieve **instance_, mpqs_client &client_) { ... switch (type) { case MPQS_DATA: ... break; case POLYNOMIAL_DATA: ... break; default: break; } }

    Read the article

< Previous Page | 219 220 221 222 223 224 225 226 227 228 229 230  | Next Page >