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  • Unit Testing Framework for XQuery

    - by Knut Vatsendvik
    This posting provides a unit testing framework for XQuery using Oracle Service Bus. It allows you to write a test case to run your XQuery transformations in an automated fashion. When the test case is run, the framework returns any differences found in the response. The complete code sample with install instructions can be downloaded from here. Writing a Unit Test You start a new Test Case by creating a Proxy Service from Workshop that comes with Oracle Service Bus. In the General Configuration page select Service Type to be Messaging Service           In the Message Type Configuration page link both the Request & Response Message Type to the TestCase element of the UnitTest.xsd schema                 The TestCase element consists of the following child elements The ID and optional Name element is simply used for reference. The Transformation element is the XQuery resource to be executed. The Input elements represents the input to run the XQuery with. The Output element represents the expected output. These XML documents are “also” represented as an XQuery resource where the XQuery function takes no arguments and returns the XML document. Why not pass the test data with the TestCase? Passing an XML structure in another XML structure is not very easy or at least not very human readable. Therefore it was chosen to represent the test data as an loadable resource in the OSB. However you are free to go ahead with another approach on this if wanted. The XMLDiff elements represents any differences found. A sample on input is shown here. Modeling the Message Flow Then the next step is to model the message flow of the Proxy Service. In the Request Pipeline create a stage node that loads the test case input data.      For this, specify a dynamic XQuery expression that evaluates at runtime to the name of a pre-registered XQuery resource. The expression is of course set by the input data from the test case.           Add a Run stage node. Assign the result of the XQuery, that is to be run, to a context variable. Define a mapping for each of the input variables added in previous stage.     Add a Compare stage. Like with the input data, load the expected output data. Do a compare using XMLDiff XQuery provided where the first argument is the loaded output test data, and the second argument the result from the Run stage. Any differences found is replaced back into the test case XMLDiff element. In case of any unexpected failure while processing, add an Error Handler to the Pipeline to capture the fault. To pass back the result add the following Insert action In the Response Pipeline. A sample on output is shown here.

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  • Single IBAction for multiple UIButtons versus single IBAction for single UIButton

    - by Miraaj
    While using story-board there are two different approaches which my team mates follow: Approach 1: To bind unique action with each button, ie: Done button - binded to - doneButtonAction Cancel button - binded to - cancelButtonAction OR Approach 2: To bind single action to multiple buttons, ie: Done button - binded to - commonButtonAction Cancel button - binded to - commonButtonAction Then in commonButtonAction they prefer to use switch case like this: - (IBAction)commonButtonAction:(id)sender { UIButton *button = (UIButton *)sender; switch (button.tag) { case 201: // done button [self doneButtonAction:sender]; break; case 202: // cancel button [self cancelButtonAction:sender]; break; default: break; } } - (void)cancelButtonAction:(id)sender { // no interesting stuff, simple dismiss of view :-( } - (void)doneButtonAction:(id)sender { // some interesting stuff ;-) } Reasoning which they give to follow approach 2 is - in each view controller during code walk through anyone can easily identify where to find code related to button actions. While others discard this idea because they say that adding an extra switch case is unnecessary and is not a common practice. What are your views?

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  • Creating a new instance, C#

    - by Dave Voyles
    This sounds like a very n00b question, but bear with me here: I'm trying to access the position of my bat (paddle) in my pong game and use it in my ball class. I'm doing this because I want a particle effect to go off at the point of contact where the ball hits the bat. Each time the ball hits the bat, I receive an error stating that I haven't created an instance of the bat. I understand that I have to (or can use a static class), but I'm not sure of how to do so in this example. I've included both my Bat and Ball classes. namespace Pong { #region Using Statements using System; using System.Collections.Generic; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; #endregion public class Ball { #region Fields private readonly Random rand; private readonly Texture2D texture; private readonly SoundEffect warp; private double direction; private bool isVisible; private float moveSpeed; private Vector2 position; private Vector2 resetPos; private Rectangle size; private float speed; private bool isResetting; private bool collided; private Vector2 oldPos; private ParticleEngine particleEngine; private ContentManager contentManager; private SpriteBatch spriteBatch; private bool hasHitBat; private AIBat aiBat; private Bat bat; #endregion #region Constructors and Destructors /// <summary> /// Constructor for the ball /// </summary> public Ball(ContentManager contentManager, Vector2 ScreenSize) { moveSpeed = 15f; speed = 0; texture = contentManager.Load<Texture2D>(@"gfx/balls/redBall"); direction = 0; size = new Rectangle(0, 0, texture.Width, texture.Height); resetPos = new Vector2(ScreenSize.X / 2, ScreenSize.Y / 2); position = resetPos; rand = new Random(); isVisible = true; hasHitBat = false; // Everything to do with particles List<Texture2D> textures = new List<Texture2D>(); textures.Add(contentManager.Load<Texture2D>(@"gfx/particle/circle")); textures.Add(contentManager.Load<Texture2D>(@"gfx/particle/star")); textures.Add(contentManager.Load<Texture2D>(@"gfx/particle/diamond")); particleEngine = new ParticleEngine(textures, new Vector2()); } #endregion #region Public Methods and Operators /// <summary> /// Checks for the collision between the bat and the ball. Sends ball in the appropriate /// direction /// </summary> public void BatHit(int block) { if (direction > Math.PI * 1.5f || direction < Math.PI * 0.5f) { hasHitBat = true; particleEngine.EmitterLocation = new Vector2(aiBat.Position.X, aiBat.Position.Y); switch (block) { case 1: direction = MathHelper.ToRadians(200); break; case 2: direction = MathHelper.ToRadians(195); break; case 3: direction = MathHelper.ToRadians(180); break; case 4: direction = MathHelper.ToRadians(180); break; case 5: direction = MathHelper.ToRadians(165); break; } } else { hasHitBat = true; particleEngine.EmitterLocation = new Vector2(bat.Position.X, bat.Position.Y); switch (block) { case 1: direction = MathHelper.ToRadians(310); break; case 2: direction = MathHelper.ToRadians(345); break; case 3: direction = MathHelper.ToRadians(0); break; case 4: direction = MathHelper.ToRadians(15); break; case 5: direction = MathHelper.ToRadians(50); break; } } if (rand.Next(2) == 0) { direction += MathHelper.ToRadians(rand.Next(3)); } else { direction -= MathHelper.ToRadians(rand.Next(3)); } AudioManager.Instance.PlaySoundEffect("hit"); } /// <summary> /// JEP - added method to slow down ball after powerup deactivates /// </summary> public void DecreaseSpeed() { moveSpeed -= 0.6f; } /// <summary> /// Draws the ball on the screen /// </summary> public void Draw(SpriteBatch spriteBatch) { if (isVisible) { spriteBatch.Begin(); spriteBatch.Draw(texture, size, Color.White); spriteBatch.End(); // Draws sprites for particles when contact is made particleEngine.Draw(spriteBatch); } } /// <summary> /// Checks for the current direction of the ball /// </summary> public double GetDirection() { return direction; } /// <summary> /// Checks for the current position of the ball /// </summary> public Vector2 GetPosition() { return position; } /// <summary> /// Checks for the current size of the ball (for the powerups) /// </summary> public Rectangle GetSize() { return size; } /// <summary> /// Grows the size of the ball when the GrowBall powerup is used. /// </summary> public void GrowBall() { size = new Rectangle(0, 0, texture.Width * 2, texture.Height * 2); } /// <summary> /// Was used to increased the speed of the ball after each point is scored. /// No longer used, but am considering implementing again. /// </summary> public void IncreaseSpeed() { moveSpeed += 0.6f; } /// <summary> /// Check for the ball to return normal size after the Powerup has expired /// </summary> public void NormalBallSize() { size = new Rectangle(0, 0, texture.Width, texture.Height); } /// <summary> /// Check for the ball to return normal speed after the Powerup has expired /// </summary> public void NormalSpeed() { moveSpeed += 15f; } /// <summary> /// Checks to see if ball went out of bounds, and triggers warp sfx /// </summary> public void OutOfBounds() { // Checks if the player is still alive or not if (isResetting) { AudioManager.Instance.PlaySoundEffect("warp"); { // Used to stop the the issue where the ball hit sfx kept going off when detecting collison isResetting = false; AudioManager.Instance.Dispose(); } } } /// <summary> /// Speed for the ball when Speedball powerup is activated /// </summary> public void PowerupSpeed() { moveSpeed += 20.0f; } /// <summary> /// Check for where to reset the ball after each point is scored /// </summary> public void Reset(bool left) { if (left) { direction = 0; } else { direction = Math.PI; } // Used to stop the the issue where the ball hit sfx kept going off when detecting collison isResetting = true; position = resetPos; // Resets the ball to the center of the screen isVisible = true; speed = 15f; // Returns the ball back to the default speed, in case the speedBall was active if (rand.Next(2) == 0) { direction += MathHelper.ToRadians(rand.Next(30)); } else { direction -= MathHelper.ToRadians(rand.Next(30)); } } /// <summary> /// Shrinks the ball when the ShrinkBall powerup is activated /// </summary> public void ShrinkBall() { size = new Rectangle(0, 0, texture.Width / 2, texture.Height / 2); } /// <summary> /// Stops the ball each time it is reset. Ex: Between points / rounds /// </summary> public void Stop() { isVisible = true; speed = 0; } /// <summary> /// Updates position of the ball /// </summary> public void UpdatePosition() { size.X = (int)position.X; size.Y = (int)position.Y; oldPos.X = position.X; oldPos.Y = position.Y; position.X += speed * (float)Math.Cos(direction); position.Y += speed * (float)Math.Sin(direction); bool collided = CheckWallHit(); particleEngine.Update(); // Stops the issue where ball was oscillating on the ceiling or floor if (collided) { position.X = oldPos.X + speed * (float)Math.Cos(direction); position.Y = oldPos.Y + speed * (float)Math.Sin(direction); } } #endregion #region Methods /// <summary> /// Checks for collision with the ceiling or floor. 2*Math.pi = 360 degrees /// </summary> private bool CheckWallHit() { while (direction > 2 * Math.PI) { direction -= 2 * Math.PI; return true; } while (direction < 0) { direction += 2 * Math.PI; return true; } if (position.Y <= 0 || (position.Y > resetPos.Y * 2 - size.Height)) { direction = 2 * Math.PI - direction; return true; } return true; } #endregion } } namespace Pong { using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.Graphics; using System; public class Bat { public Vector2 Position; public float moveSpeed; public Rectangle size; private int points; private int yHeight; private Texture2D leftBat; public float turbo; public float recharge; public float interval; public bool isTurbo; /// <summary> /// Constructor for the bat /// </summary> public Bat(ContentManager contentManager, Vector2 screenSize, bool side) { moveSpeed = 7f; turbo = 15f; recharge = 100f; points = 0; interval = 5f; leftBat = contentManager.Load<Texture2D>(@"gfx/bats/batGrey"); size = new Rectangle(0, 0, leftBat.Width, leftBat.Height); // True means left bat, false means right bat. if (side) Position = new Vector2(30, screenSize.Y / 2 - size.Height / 2); else Position = new Vector2(screenSize.X - 30, screenSize.Y / 2 - size.Height / 2); yHeight = (int)screenSize.Y; } public void IncreaseSpeed() { moveSpeed += .5f; } /// <summary> /// The speed of the bat when Turbo is activated /// </summary> public void Turbo() { moveSpeed += 8.0f; } /// <summary> /// Returns the speed of the bat back to normal after Turbo is deactivated /// </summary> public void DisableTurbo() { moveSpeed = 7.0f; isTurbo = false; } /// <summary> /// Returns the bat to the nrmal size after the Grow/Shrink powerup has expired /// </summary> public void NormalSize() { size = new Rectangle(0, 0, leftBat.Width, leftBat.Height); } /// <summary> /// Checks for the size of the bat /// </summary> public Rectangle GetSize() { return size; } /// <summary> /// Adds point to the player or the AI after scoring. Currently Disabled. /// </summary> public void IncrementPoints() { points++; } /// <summary> /// Checks for the number of points at the moment /// </summary> public int GetPoints() { return points; } /// <summary> /// Sets thedefault starting position for the bats /// </summary> /// <param name="position"></param> public void SetPosition(Vector2 position) { if (position.Y < 0) { position.Y = 0; } if (position.Y > yHeight - size.Height) { position.Y = yHeight - size.Height; } this.Position = position; } /// <summary> /// Checks for the current position of the bat /// </summary> public Vector2 GetPosition() { return Position; } /// <summary> /// Controls the bat moving up the screen /// </summary> public void MoveUp() { SetPosition(Position + new Vector2(0, -moveSpeed)); } /// <summary> /// Controls the bat moving down the screen /// </summary> public void MoveDown() { SetPosition(Position + new Vector2(0, moveSpeed)); } /// <summary> /// Updates the position of the AI bat, in order to track the ball /// </summary> /// <param name="ball"></param> public virtual void UpdatePosition(Ball ball) { size.X = (int)Position.X; size.Y = (int)Position.Y; } /// <summary> /// Resets the bat to the center location after a new game starts /// </summary> public void ResetPosition() { SetPosition(new Vector2(GetPosition().X, yHeight / 2 - size.Height)); } /// <summary> /// Used for the Growbat powerup /// </summary> public void GrowBat() { // Doubles the size of the bat collision size = new Rectangle(0, 0, leftBat.Width * 2, leftBat.Height * 2); } /// <summary> /// Used for the Shrinkbat powerup /// </summary> public void ShrinkBat() { // 1/2 the size of the bat collision size = new Rectangle(0, 0, leftBat.Width / 2, leftBat.Height / 2); } /// <summary> /// Draws the bats /// </summary> public virtual void Draw(SpriteBatch batch) { batch.Draw(leftBat, size, Color.White); } } }

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  • Strengthening code with possibly useless exception handling

    - by rdurand
    Is it a good practice to implement useless exception handling, just in case another part of the code is not coded correctly? Basic example A simple one, so I don't loose everybody :). Let's say I'm writing an app that will display a person's information (name, address, etc.), the data being extracted from a database. Let's say I'm the one coding the UI part, and someone else is writing the DB query code. Now imagine that the specifications of your app say that if the person's information is incomplete (let's say, the name is missing in the database), the person coding the query should handle this by returning "NA" for the missing field. What if the query is poorly coded and doesn't handle this case? What if the guy who wrote the query handles you an incomplete result, and when you try to display the informations, everything crashes, because your code isn't prepared to display empty stuff? This example is very basic. I believe most of you will say "it's not your problem, you're not responsible for this crash". But, it's still your part of the code which is crashing. Another example Let's say now I'm the one writing the query. The specifications don't say the same as above, but that the guy writing the "insert" query should make sure all the fields are complete when adding a person to the database to avoid inserting incomplete information. Should I protect my "select" query to make sure I give the UI guy complete informations? The questions What if the specifications don't explicitly say "this guy is the one in charge of handling this situation"? What if a third person implements another query (similar to the first one, but on another DB) and uses your UI code to display it, but doesn't handle this case in his code? Should I do what's necessary to prevent a possible crash, even if I'm not the one supposed to handle the bad case? I'm not looking for an answer like "(s)he's the one responsible for the crash", as I'm not solving a conflict here, I'd like to know, should I protect my code against situations it's not my responsibility to handle? Here, a simple "if empty do something" would suffice. In general, this question tackles redundant exception handling. I'm asking it because when I work alone on a project, I may code 2-3 times a similar exception handling in successive functions, "just in case" I did something wrong and let a bad case come through.

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  • C#/.NET Little Wonders: Static Char Methods

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Often times in our code we deal with the bigger classes and types in the BCL, and occasionally forgot that there are some nice methods on the primitive types as well.  Today we will discuss some of the handy static methods that exist on the char (the C# alias of System.Char) type. The Background I was examining a piece of code this week where I saw the following: 1: // need to get the 5th (offset 4) character in upper case 2: var type = symbol.Substring(4, 1).ToUpper(); 3:  4: // test to see if the type is P 5: if (type == "P") 6: { 7: // ... do something with P type... 8: } Is there really any error in this code?  No, but it still struck me wrong because it is allocating two very short-lived throw-away strings, just to store and manipulate a single char: The call to Substring() generates a new string of length 1 The call to ToUpper() generates a new upper-case version of the string from Step 1. In my mind this is similar to using ToUpper() to do a case-insensitive compare: it isn’t wrong, it’s just much heavier than it needs to be (for more info on case-insensitive compares, see #2 in 5 More Little Wonders). One of my favorite books is the C++ Coding Standards: 101 Rules, Guidelines, and Best Practices by Sutter and Alexandrescu.  True, it’s about C++ standards, but there’s also some great general programming advice in there, including two rules I love:         8. Don’t Optimize Prematurely         9. Don’t Pessimize Prematurely We all know what #8 means: don’t optimize when there is no immediate need, especially at the expense of readability and maintainability.  I firmly believe this and in the axiom: it’s easier to make correct code fast than to make fast code correct.  Optimizing code to the point that it becomes difficult to maintain often gains little and often gives you little bang for the buck. But what about #9?  Well, for that they state: “All other things being equal, notably code complexity and readability, certain efficient design patterns and coding idioms should just flow naturally from your fingertips and are no harder to write then the pessimized alternatives. This is not premature optimization; it is avoiding gratuitous pessimization.” Or, if I may paraphrase: “where it doesn’t increase the code complexity and readability, prefer the more efficient option”. The example code above was one of those times I feel where we are violating a tacit C# coding idiom: avoid creating unnecessary temporary strings.  The code creates temporary strings to hold one char, which is just unnecessary.  I think the original coder thought he had to do this because ToUpper() is an instance method on string but not on char.  What he didn’t know, however, is that ToUpper() does exist on char, it’s just a static method instead (though you could write an extension method to make it look instance-ish). This leads me (in a long-winded way) to my Little Wonders for the day… Static Methods of System.Char So let’s look at some of these handy, and often overlooked, static methods on the char type: IsDigit(), IsLetter(), IsLetterOrDigit(), IsPunctuation(), IsWhiteSpace() Methods to tell you whether a char (or position in a string) belongs to a category of characters. IsLower(), IsUpper() Methods that check if a char (or position in a string) is lower or upper case ToLower(), ToUpper() Methods that convert a single char to the lower or upper equivalent. For example, if you wanted to see if a string contained any lower case characters, you could do the following: 1: if (symbol.Any(c => char.IsLower(c))) 2: { 3: // ... 4: } Which, incidentally, we could use a method group to shorten the expression to: 1: if (symbol.Any(char.IsLower)) 2: { 3: // ... 4: } Or, if you wanted to verify that all of the characters in a string are digits: 1: if (symbol.All(char.IsDigit)) 2: { 3: // ... 4: } Also, for the IsXxx() methods, there are overloads that take either a char, or a string and an index, this means that these two calls are logically identical: 1: // check given a character 2: if (char.IsUpper(symbol[0])) { ... } 3:  4: // check given a string and index 5: if (char.IsUpper(symbol, 0)) { ... } Obviously, if you just have a char, then you’d just use the first form.  But if you have a string you can use either form equally well. As a side note, care should be taken when examining all the available static methods on the System.Char type, as some seem to be redundant but actually have very different purposes.  For example, there are IsDigit() and IsNumeric() methods, which sound the same on the surface, but give you different results. IsDigit() returns true if it is a base-10 digit character (‘0’, ‘1’, … ‘9’) where IsNumeric() returns true if it’s any numeric character including the characters for ½, ¼, etc. Summary To come full circle back to our opening example, I would have preferred the code be written like this: 1: // grab 5th char and take upper case version of it 2: var type = char.ToUpper(symbol[4]); 3:  4: if (type == 'P') 5: { 6: // ... do something with P type... 7: } Not only is it just as readable (if not more so), but it performs over 3x faster on my machine:    1,000,000 iterations of char method took: 30 ms, 0.000050 ms/item.    1,000,000 iterations of string method took: 101 ms, 0.000101 ms/item. It’s not only immediately faster because we don’t allocate temporary strings, but as an added bonus there less garbage to collect later as well.  To me this qualifies as a case where we are using a common C# performance idiom (don’t create unnecessary temporary strings) to make our code better. Technorati Tags: C#,CSharp,.NET,Little Wonders,char,string

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  • Algorithm to find average position

    - by Simran kaur
    In the given diagram, I have the extreme left and right points, that is -2 and 4 in this case. So, obviously, I can calculate the width which is 6 in this case. What we know: The number of partitions:3 in this case The partition number at at any point i.e which one is 1st,second or third partition (numbered starting from left) What I want: The position of the purple line drawn which is positio of average of a particular partition So, basically I just want a generalized formula to calculate position of the average at any point.

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  • Memento with optional state?

    - by Korey Hinton
    EDIT: As pointed out by Steve Evers and pdr, I am not correctly implementing the Memento pattern, my design is actually State pattern. Menu Program I built a console-based menu program with multiple levels that selects a particular test to run. Each level more precisely describes the operation. At any level you can type back to go back one level (memento). Level 1: Server Type? [1] Server A [2] Server B Level 2: Server environment? [1] test [2] production Level 3: Test type? [1] load [2] unit Level 4: Data Collection? [1] Legal docs [2] Corporate docs Level 4.5 (optional): Load Test Type [2] Multi TIF [2] Single PDF Level 5: Command Type? [1] Move [2] Copy [3] Remove [4] Custom Level 6: Enter a keyword [setup, cleanup, run] Design States PROBLEM: Right now the STATES enum is the determining factor as to what state is BACK and what state is NEXT yet it knows nothing about what the current memento state is. Has anyone experienced a similar issue and found an effective way to handle mementos with optional state? static enum STATES { SERVER, ENVIRONMENT, TEST_TYPE, COLLECTION, COMMAND_TYPE, KEYWORD, FINISHED } Possible Solution (Not-flexible) In reference to my code below, every case statement in the Menu class could check the state of currentMemo and then set the STATE (enum) accordingly to pass to the Builder. However, this doesn't seem flexible very flexible to change and I'm struggling to see an effective way refactor the design. class Menu extends StateConscious { private State state; private Scanner reader; private ServerUtils utility; Menu() { state = new State(); reader = new Scanner(System.in); utility = new ServerUtils(); } // Recurring menu logic public void startPromptingLoop() { List<State> states = new ArrayList<>(); states.add(new State()); boolean redoInput = false; boolean userIsDone = false; while (true) { // get Memento from last loop Memento currentMemento = states.get(states.size() - 1) .saveMemento(); if (currentMemento == null) currentMemento = new Memento.Builder(0).build(); if (!redoInput) System.out.println(currentMemento.prompt); redoInput = false; // prepare Memento for next loop Memento nextMemento = null; STATES state = STATES.values()[states.size() - 1]; // get user input String selection = reader.nextLine(); switch (selection) { case "exit": reader.close(); return; // only escape case "quit": nextMemento = new Memento.Builder(first(), currentMemento, selection).build(); states.clear(); break; case "back": nextMemento = new Memento.Builder(previous(state), currentMemento, selection).build(); if (states.size() <= 1) { states.remove(0); } else { states.remove(states.size() - 1); states.remove(states.size() - 1); } break; case "1": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; case "2": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; case "3": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; case "4": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; default: if (state.equals(STATES.CATEGORY)) { String command = selection; System.out.println("Executing " + command + " command on: " + currentMemento.type + " " + currentMemento.environment); utility.executeCommand(currentMemento.nickname, command); userIsDone = true; states.clear(); nextMemento = new Memento.Builder(first(), currentMemento, selection).build(); } else if (state.equals(STATES.KEYWORD)) { nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); states.clear(); nextMemento = new Memento.Builder(first(), currentMemento, selection).build(); } else { redoInput = true; System.out.println("give it another try"); continue; } break; } if (userIsDone) { // start the recurring menu over from the beginning for (int i = 0; i < states.size(); i++) { if (i != 0) { states.remove(i); // remove all except first } } reader = new Scanner(System.in); this.state = new State(); userIsDone = false; } if (!redoInput) { this.state.restoreMemento(nextMemento); states.add(this.state); } } } }

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  • Get coordinates of arraylist

    - by opiop65
    Here's my map class: public class map{ public static final int CLEAR = 0; public static final ArrayList<Integer> STONE = new ArrayList<Integer>(); public static final int GRASS = 2; public static final int DIRT = 3; public static final int WIDTH = 32; public static final int HEIGHT = 24; public static final int TILE_SIZE = 25; // static int[][] map = new int[WIDTH][HEIGHT]; ArrayList<ArrayList<Integer>> map = new ArrayList<ArrayList<Integer>>(WIDTH * HEIGHT); enum tiles { air, grass, stone, dirt } Image air, grass, stone, dirt; Random rand = new Random(); public Map() { /* default map */ /*for(int y = 0; y < WIDTH; y++){ map[y][y] = (rand.nextInt(2)); System.out.println(map[y][y]); }*/ /*for (int y = 18; y < HEIGHT; y++) { for (int x = 0; x < WIDTH; x++) { map[x][y] = STONE; } } for (int y = 18; y < 19; y++) { for (int x = 0; x < WIDTH; x++) { map[x][y] = GRASS; } } for (int y = 19; y < 20; y++) { for (int x = 0; x < WIDTH; x++) { map[x][y] = DIRT; } }*/ for (int y = 0; y < HEIGHT; y++) { for(int x = 0; x < WIDTH; x++){ map.set(x * WIDTH + y, STONE); } } try { init(null, null); } catch (SlickException e) { e.printStackTrace(); } render(null, null, null); } public void init(GameContainer gc, StateBasedGame sbg) throws SlickException { air = new Image("res/air.png"); grass = new Image("res/grass.png"); stone = new Image("res/stone.png"); dirt = new Image("res/dirt.png"); } public void render(GameContainer gc, StateBasedGame sbg, Graphics g) { for (int x = 0; x < WIDTH; x++) { for (int y = 0; y < HEIGHT; y++) { switch (map.get(x * WIDTH + y)) { case CLEAR: air.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; case STONE: stone.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; case GRASS: grass.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; case DIRT: dirt.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; } } } } public static boolean blocked(float x, float y) { return map[(int) x][(int) y] == STONE; } public static Rectangle blockBounds(int x, int y) { return (new Rectangle(x, y, TILE_SIZE, TILE_SIZE)); } } Specifically I am looking at this: for (int x = 0; x < WIDTH; x++) { for (int y = 0; y < HEIGHT; y++) { switch (map.get(x * WIDTH + y).intValue()) { case CLEAR: air.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; case STONE: stone.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; case GRASS: grass.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; case DIRT: dirt.draw(x * TILE_SIZE, y * TILE_SIZE, TILE_SIZE, TILE_SIZE); break; } } } How can I access the coordinates of my arraylist map and then draw the tiles to the screen? Thanks!

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  • Switch or a Dictionary when assigning to new object

    - by KChaloux
    Recently, I've come to prefer mapping 1-1 relationships using Dictionaries instead of Switch statements. I find it to be a little faster to write and easier to mentally process. Unfortunately, when mapping to a new instance of an object, I don't want to define it like this: var fooDict = new Dictionary<int, IBigObject>() { { 0, new Foo() }, // Creates an instance of Foo { 1, new Bar() }, // Creates an instance of Bar { 2, new Baz() } // Creates an instance of Baz } var quux = fooDict[0]; // quux references Foo Given that construct, I've wasted CPU cycles and memory creating 3 objects, doing whatever their constructors might contain, and only ended up using one of them. I also believe that mapping other objects to fooDict[0] in this case will cause them to reference the same thing, rather than creating a new instance of Foo as intended. A solution would be to use a lambda instead: var fooDict = new Dictionary<int, Func<IBigObject>>() { { 0, () => new Foo() }, // Returns a new instance of Foo when invoked { 1, () => new Bar() }, // Ditto Bar { 2, () => new Baz() } // Ditto Baz } var quux = fooDict[0](); // equivalent to saying 'var quux = new Foo();' Is this getting to a point where it's too confusing? It's easy to miss that () on the end. Or is mapping to a function/expression a fairly common practice? The alternative would be to use a switch: IBigObject quux; switch(someInt) { case 0: quux = new Foo(); break; case 1: quux = new Bar(); break; case 2: quux = new Baz(); break; } Which invocation is more acceptable? Dictionary, for faster lookups and fewer keywords (case and break) Switch: More commonly found in code, doesn't require the use of a Func< object for indirection.

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  • Automated Acceptance tests under specific contraints

    - by HH_
    This is a follow up to my previous question, which was a bit general, so I'll be asking for a more precise situation. I want to automate acceptance testing on a web application. Briefly, this application allows the user to create contracts for subscribers with the two constraints: You cannot create more than one contract for a subscriber. Once a contract is created, it cannot be deleted (from the UI) Let's say TestCreate is a test case with tests for the normal creation of a contract. The constraints have introduced complexities to the testing process, mainly dependencies between test cases and test executions. Before we run TestCreate we need to make sure that the application is in a suitable state (the subscriber has no contract) If we run TestCreate twice, the second run will fail since the state of the application will have changed. So we need to revert back to the initial state (i.e. delete the contract), which is impossible to do from the UI. More generally, after each test case we should guarantee that the state is reverted back. And since, in this case, it is impossible to do it from the UI, how do you handle this? Possible solution: I thought about doing a backup of the database in the state that I desire, and after each test case, run a script which deletes the db and restores the backup. However, I find that to be too heavy to do for each single test case. In addition, what if some information are stored in files? or in multiple or unaccessible databases? My question: In this situation, what would an experienced tester do to write automated and maintanable tests. Thank you. More info: I'm trying to integrate tests into a BDD framework, which I find to be a neat solution for test documentation and communication, but it does not solve this particular problem (it even makes it harder)

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  • Marshalling C# Structs into DX11 cbuffers

    - by Craig
    I'm having some issues with the packing of my structure in C# and passing them through to cbuffers I have registered in HLSL. When I pack my struct in one manner the information seems to be able to pass to the shader: [StructLayout(LayoutKind.Explicit, Size = 16)] internal struct TestStruct { [FieldOffset(0)] public Vector3 mEyePosition; [FieldOffset(12)] public int type; } This works perfectly when used against this HLSL fragment: cbuffer PerFrame : register(b0) { Vector3 eyePos; int type; } float3 GetColour() { float3 returnColour = float(0.0f, 0.0f, 0.0f); switch(type) { case 0: returnColour = float3(1.0f, 0.0f, 0.0f); break; case 1: returnColour = float3(0.0f, 1.0f, 0.0f); break; case 2: returnColour = float3(0.0f, 0.0f, 1.0f); break; } return returnColour; } However, when I use the following structure definitions... // Note this is 16 because HLSL packs in 4 float 'chunks'. // It is also simplified, but still demonstrates the problem. [StructLayout(Layout.Explicit, Size = 16)] internal struct InternalTestStruct { [FieldOffset(0)] public int type; } [StructLayout(LayoutKind.Explicit, Size = 32)] internal struct TestStruct { [FieldOffset(0)] public Vector3 mEyePosition; //Missing 4 bytes here for correct packing. [FieldOffset(16)] public InternalTestStruct mInternal; } ... the following HLSL fragment no longer works. struct InternalType { int type; } cbuffer PerFrame : register(b0) { Vector3 eyePos; InternalType internalStruct; } float3 GetColour() { float3 returnColour = float(0.0f, 0.0f, 0.0f); switch(internaltype.type) { case 0: returnColour = float3(1.0f, 0.0f, 0.0f); break; case 1: returnColour = float3(0.0f, 1.0f, 0.0f); break; case 2: returnColour = float3(0.0f, 0.0f, 1.0f); break; } return returnColour; } Is there a problem with the way I am packing the struct, or is it another issue? To re-iterate: I can pass a struct in a cbuffer so long as it does not contain a nested struct.

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  • Passing class names or objects?

    - by nischayn22
    I have a switch statement switch ( $id ) { case 'abc': return 'Animal'; case 'xyz': return 'Human'; //many more } I am returning class names,and use them to call some of their static functions using call_user_func(). Instead I can also create a object of that class, return that and then call the static function from that object as $object::method($param) switch ( $id ) { case 'abc': return new Animal; case 'xyz': return new Human; //many more } Which way is efficient? To make this question broader : I have classes that have mostly all static methods right now, putting them into classes is kind of a grouping idea here (for example the DB table structure of Animal is given by class Animal and so for Human class). I need to access many functions from these classes so the switch needs to give me access to the class

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  • Is there any logical relation between different types of UML diagrams?

    - by user363295
    I'm trying to find out ,that is there any relation between different types of UML diagrams, for example, once you developed a use case, should it be an event for each of them in a sequence diagram, or is there any exact relation between the use case and class diagrams. By the way my main focus is on the below diagrams: Use case class diagram activity sequence event if you think I need any extra diagram to be included so it can be used to connecting the above diagrams to each other, please mention it too. Thanks In Advance

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  • Is my site hacked, or does Google have problems? [duplicate]

    - by Bondye
    Possible Duplicate: Titles in Google results contain spammy prefixes I have a webshop online and I have some problems with redirecting from Google. Case 1 When I Google for my site at google.com in Iron SWR (safe Chrome version) and I click the first link I get the correct page. Case 2 When I Google for my site at google.nl in Iron SWR (safe Chrome version) and I click the first link Google will redirect me to a spam site. Case 3 When I Google for my site in Google Chrome and I click the first link Google will redirect me to a spam site. Case 4 When I Google for my site in FireFox and I click the first link Google will redirect me to a spam site. Case 5 When I Google for my site in Internet Explorer and I click the first link Google will redirect me a page that tells me the site is offline. HELP WHAT TO DO? I checked the .htaccess but this file is correct. I checked the index.php file but this one is also correct. What can I do? Hacked or does Google has trouble?

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  • How should I refactor switch statements like this (Switching on type) to be more OO?

    - by Taytay
    I'm seeing some code like this in our code base, and want to refactor it: (Typescript psuedocode follows): class EntityManager{ private findEntityForServerObject(entityType:string, serverObject:any):IEntity { var existingEntity:IEntity = null; switch(entityType) { case Types.UserSetting: existingEntity = this.getUserSettingByUserIdAndSettingName(serverObject.user_id, serverObject.setting_name); break; case Types.Bar: existingEntity = this.getBarByUserIdAndId(serverObject.user_id, serverObject.id); break; //Lots more case statements here... } return existingEntity; } } The downsides of switching on type are self-explanatory. Normally, when switching behavior based on type, I try to push the behavior into subclasses so that I can reduce this to a single method call, and let polymorphism take care of the rest. However, the following two things are giving me pause: 1) I don't want to couple the serverObject with the class that is storing all of these objects. It doesn't know where to look for entities of a certain type. And unfortunately, the identity of a type of ServerObject varies with the type of ServerObject. (So sometimes it's just an ID, other times it's a combination of an id and a uniquely identifying string, etc). And this behavior doesn't belong down there on those subclasses. It is the responsibility of the EntityManager and its delegates. 2) In this case, I can't modify the ServerObject classes since they're plain old data objects. It should be mentioned that I've got other instances of the above method that take a parameter like "IEntity" and proceed to do almost the same thing (but slightly modify the name of the methods they're calling to get the identity of the entity). So, we might have: case Types.Bar: existingEntity = this.getBarByUserIdAndId(entity.getUserId(), entity.getId()); break; So in that case, I can change the entity interface and subclasses, but this isn't behavior that belongs in that class. So, I think that points me to some sort of map. So eventually I will call: private findEntityForServerObject(entityType:string, serverObject:any):IEntity { return aMapOfSomeSort[entityType].findByServerObject(serverObject); } private findEntityForEntity(someEntity:IEntity):IEntity { return aMapOfSomeSort[someEntity.entityType].findByEntity(someEntity); } Which means I need to register some sort of strategy classes/functions at runtime with this map. And again, I darn well better remember to register one for each my my types, or I'll get a runtime exception. Is there a better way to refactor this? I feel like I'm missing something really obvious here.

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  • Serial Port Not getting closed. I want to release the COM port ...

    - by sunil
    Serial Port Not getting closed. I want to release the COM port ... Below is my code.... import java.io.*; import java.util.*; import gnu.io.*; public class ReadCommPort implements SerialPortEventListener { static CommPortIdentifier portId; static Enumeration portList; InputStream inputStream; OutputStream outputStream; public SerialPort serialPort; List byteList = new ArrayList(); public static Message message = null; public void readData() { boolean portFound = false; String defaultPort = "COM1"; portList = CommPortIdentifier.getPortIdentifiers(); while ( portList.hasMoreElements() ) { portId = ( CommPortIdentifier )portList.nextElement(); if ( portId.getPortType() == CommPortIdentifier.PORT_SERIAL ) { if ( portId.getName().equals( defaultPort ) ) { System.out.println( "Found port: " + defaultPort ); portFound = true; buildSerialPort(); } } } if ( ! portFound ) { System.out.println( "port " + defaultPort + " not found." ); } } public void buildSerialPort() { try { serialPort = (SerialPort) portId.open( "ReadCommPort", 1 ); inputStream = serialPort.getInputStream(); outputStream = serialPort.getOutputStream(); serialPort.addEventListener( this ); serialPort.notifyOnDataAvailable(true); serialPort.setSerialPortParams( 2400, SerialPort.DATABITS_7, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE ); } catch ( Exception e ) { e.printStackTrace(); } } @SuppressWarnings("unchecked") public void serialEvent( SerialPortEvent event ) { switch ( event.getEventType() ) { case SerialPortEvent.BI: System.out.println( "BI"); break; case SerialPortEvent.OE: System.out.println( "OE"); break; case SerialPortEvent.FE: System.out.println( "FE"); break; case SerialPortEvent.PE: System.out.println( "PE"); break; case SerialPortEvent.CD: System.out.println( "CD"); break; case SerialPortEvent.CTS: System.out.println( "CTS"); break; case SerialPortEvent.DSR: System.out.println( "DSR"); break; case SerialPortEvent.RI: System.out.println( "RI"); break; case SerialPortEvent.OUTPUT_BUFFER_EMPTY: System.out.println( "OUTPUT_BUFFER_EMPTY"); break; case SerialPortEvent.DATA_AVAILABLE : try { int len = inputStream.available(); byte[] readBuffer = new byte[ len ]; // processing data code.. // close the port // release all resources... serialPort.removeEventListener(); try { serialPort.addEventListener( null ); } catch (TooManyListenersException e) { e.printStackTrace(); } inputStream.close(); outputStream.close(); serialPort.close(); } catch ( IOException e ) { e.printStackTrace(); } break; } } public static void main(String[] args) { new ReadCommPort().readData(); } }

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  • File Fix-it codegolf (GCJ 2010 1B-A)

    - by KirarinSnow
    Last year (2009), the Google Code Jam featured an interesting problem as the first problem in Round 1B: Decision Tree As the problem seemed tailored for Lisp-like languages, we spontaneously had an exciting codegolf here on SO, in which a few languages managed to solve the problem in fewer characters than any Lisp variety, using quite a number of different techniques. This year's Round 1B Problem A (File Fix-it) also seems tailored for a particular family of languages, Unix shell scripts. So continuing the "1B-A tradition" would be appropriate. :p But which language will end up with the shortest code? Let us codegolf and see! Problem description (adapted from official page): You are given T test cases. Each test case contains N lines that list the full path of all directories currently existing on your computer. For example: /home/awesome /home/awesome/wheeeeeee /home/awesome/wheeeeeee/codegolfrocks /home/thecakeisalie Next, you are given M lines that list the full path of directories you would like to create. They are in the same format as the previous examples. You can create a directory using the mkdir command, but you can only do so if the parent directory already exists. For example, to create the directories /pyonpyon/fumufumu/yeahyeah and /pyonpyon/fumufumu/yeahyeahyeah, you would need to use mkdir four times: mkdir /pyonpyon mkdir /pyonpyon/fumufumu mkdir /pyonpyon/fumufumu/yeahyeah mkdir /pyonpyon/fumufumu/yeahyeahyeah For each test case, return the number of times you have to call mkdir to create all the directories you would like to create. Input Input consists of a text file whose first line contains the integer T, the number of test cases. The rest of the file contains the test cases. Each test case begins with a line containing the integers N and M, separated by a space. The next N lines contain the path of each directory currently existing on your computer (not including the root directory /). This is a concatenation of one or more non-empty lowercase alphanumeric strings, each preceded by a single /. The following M lines contain the path of each directory you would like to create. Output For each case, print one line containing Case #X: Y, where X is the case number and Y is the solution. Limits 1 = T = 100. 0 = N = 100. 1 = M = 100. Each path contains at most 100 characters. Every path appears only once in the list of directories already on your computer, or in the list of desired directories. However, a path may appear on both lists, as in example case #3 below. If a directory is in the list of directories already on your computer, its parent directory will also be listed, with the exception of the root directory /. The input file is at most 100,000 bytes long. Example Larger sample test cases may be downloaded here. Input: 3 0 2 /home/sparkle/pyon /home/sparkle/cakes 1 3 /z /z/y /z/x /y/y 2 1 /moo /moo/wheeeee /moo Output: Case #1: 4 Case #2: 4 Case #3: 0 Code Golf Please post your shortest code in any language that solves this problem. Input and output may be handled via stdin and stdout or by other files of your choice. Please include a disclaimer if your code has the potential to modify or delete existing files when executed. Winner will be the shortest solution (by byte count) in a language with an implementation existing prior to the start of Round 1B 2010.

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  • Creating my own Stack

    - by Malaken
    I am creating my own stack for my data structures class. For our assignment we are using the assignment to convert a real-time infix equation into a postfix equation. I thought my program: took input determines if it was digit or number(operand) prints it out determines if input is operator (+,-,/,*) adds to stack or prints out, depending on stack precedence Instead it prints out the operands as expect, but I get this error when I enter an operator .../dorun.sh line 33: 4136 Segmentation fault sh "$" [code] #include using namespace std; class DishWell{ public: char ReturnEnd(){ return Well.back(); } void Push(char x){ Well.push_back(x); } void Pop(){ Well.pop_back(); } bool IsEmpty(){ return Well.empty(); } private: vector<char> Well; }; #include <iostream> bool Precidence(char Input, char Stack){ int InputPrecidence,StackPrecidence; switch (Input){ case '*': InputPrecidence = 4; break; case '/': InputPrecidence = 4; break; case '+': InputPrecidence = 3; break; case '-': InputPrecidence = 3; break; case '(': InputPrecidence = 2; break; default: InputPrecidence = 0; } switch (Stack){ case '*': StackPrecidence = 4; break; case '/': StackPrecidence = 4; break; case '+': StackPrecidence = 3; break; case '-': StackPrecidence = 3; break; case '(': StackPrecidence = 2; break; default: StackPrecidence = 0; } if(InputPrecidence>StackPrecidence) return true; else return false; } int main(int argc, char** argv) { DishWell DishTray; char Input; bool InputFlag; InputFlag = true; while(InputFlag){ cin>>Input; if((((Input>='a'&&Input<='z')||(Input>='A'&&Input<='Z'))|| (Input>='0'&&Input<='9')))//If Digit or Number cout<<Input; if((Input=='*'||Input=='/'||Input=='+'||Input=='-')){//if operand if(Precidence(Input,DishTray.ReturnEnd())) DishTray.Push(Input); else if(!Precidence(Input,DishTray.ReturnEnd())) cout<<Input; } else if(!((((Input>='a'&&Input<='z')||(Input>='A'&&Input<='Z'))|| (Input>='0'&&Input<='9')))||((Input=='*'||Input=='/'||Input=='+'||Input=='-')))//if not digit/numer or operand InputFlag = false; } while(!DishTray.IsEmpty()){ cout<<DishTray.ReturnEnd(); DishTray.Pop(); } return 0; [code] My code is very length, I know, but I appreciate help. Especially any times for efficency or future coding. Thanks again P.S. Dr. Zemoudeh, this is your student Macaire

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  • EF Code first + Delete Child Object from Parent?

    - by ebb
    I have a one-to-many relationship between my table Case and my other table CaseReplies. I'm using EF Code First and now wants to delete a CaseReply from a Case object, however it seems impossible to do such thing because it just tries to remove the CaseId from the specific CaseReply record and not the record itself.. short: Case just removes the relationship between itself and the CaseReply.. it does not delete the CaseReply. My code: // Case.cs (Case Object) public class Case { [Key] public int Id { get; set; } public string Topic { get; set; } public string Message { get; set; } public DateTime Date { get; set; } public Guid UserId { get; set; } public virtual User User { get; set; } public virtual ICollection<CaseReply> Replies { get; set; } } // CaseReply.cs (CaseReply Object) public class CaseReply { [Key] public int Id { get; set; } public string Message { get; set; } public DateTime Date { get; set; } public int CaseId { get; set; } public Guid UserId { get; set; } public virtual User User { get; set; } public virtual Case Case { get; set; } } // RepositoryBase.cs public class RepositoryBase<T> : IRepository<T> where T : class { public IDbContext Context { get; private set; } public IDbSet<T> ObjectSet { get; private set; } public RepositoryBase(IDbContext context) { Contract.Requires(context != null); Context = context; if (context != null) { ObjectSet = Context.CreateDbSet<T>(); if (ObjectSet == null) { throw new InvalidOperationException(); } } } public IRepository<T> Remove(T entity) { ObjectSet.Remove(entity); return this; } public IRepository<T> SaveChanges() { Context.SaveChanges(); return this; } } // CaseRepository.cs public class CaseRepository : RepositoryBase<Case>, ICaseRepository { public CaseRepository(IDbContext context) : base(context) { Contract.Requires(context != null); } public bool RemoveCaseReplyFromCase(int caseId, int caseReplyId) { Case caseToRemoveReplyFrom = ObjectSet.Include(x => x.Replies).FirstOrDefault(x => x.Id == caseId); var delete = caseToRemoveReplyFrom.Replies.FirstOrDefault(x => x.Id == caseReplyId); caseToRemoveReplyFrom.Replies.Remove(delete); return Context.SaveChanges() >= 1; } } Thanks in advance.

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  • Generate random number histogram using java

    - by Chewart
    Histogram -------------------------------------------------------- 1 ****(4) 2 ******(6) 3 ***********(11) 4 *****************(17) 5 **************************(26) 6 *************************(25) 7 *******(7) 8 ***(3) 9 (0) 10 *(1) -------------------------------------------------------- basically above is what my prgram needs to do.. im missing something somewhere any help would be great :) import java.util.Random; public class Histogram { /*This is a program to generate random number histogram between 1 and 100 and generate a table */ public static void main(String args[]) { int [] randarray = new int [80]; Random random = new Random(); System.out.println("Histogram"); System.out.println("---------"); int i ; for ( i = 0; i<randarray.length;i++) { int temp = random.nextInt(100); //random numbers up to number value 100 randarray[i] = temp; } int [] histo = new int [10]; for ( i = 0; i<10; i++) { /* %03d\t, this generates the random numbers to three decimal places so the numbers are generated with a full number or number with 00's or one 0*/ if (randarray[i] <= 10) { histo[i] = histo[i] + 1; //System.out.println("*"); } else if ( randarray[i] <= 20){ histo[i] = histo[i] + 1; } else if (randarray[i] <= 30){ histo[i] = histo[i] + 1; } else if ( randarray[i] <= 40){ histo[i] = histo[i] + 1; } else if (randarray[i] <= 50){ histo[i] = histo[i] + 1; } else if ( randarray[i] <=60){ histo[i] = histo[i] + 1; } else if ( randarray[i] <=70){ histo[i] = histo[i] + 1; } else if ( randarray[i] <=80){ histo[i] = histo[i] + 1; } else if ( randarray[i] <=90){ histo[i] = histo[i] + 1; } else if ( randarray[i] <=100){ histo[i] = histo[i] + 1; } switch (randarray[i]) { case 1: System.out.print("0-10 | "); break; case 2: System.out.print("11-20 | "); break; case 3: System.out.print("21-30 | "); break; case 4: System.out.print("31-40 | "); break; case 5: System.out.print("41-50 | "); break; case 6: System.out.print("51-60 | "); break; case 7: System.out.print("61-70 | "); break; case 8: System.out.print("71-80 | "); break; case 9: System.out.print("81-90 | "); break; case 10: System.out.print("91-100 | "); } for (int i = 0; i < 80; i++) { randomNumber = random.nextInt(100) index = (randomNumber - 1) / 2; histo[index]++; } } } }

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  • how to fetch meaningful

    - by user1298017
    Hi Every body, I have connected my device to serial port. I am using Javax.comm API to fetch the data from my device. On tapping of card i am reading data as below: newData = inputStream.read(); and able to fetch data : 0 128 161 132 132 132 132 132 132 132 101 65 2 226 99 98 132 132 132 132 132 132 132 132 131 134 164 132 132 132 165 134 132 196 230 167 132 132 132 132 132 132 132 197 196 132 133 132 132 164 197 132 132 198 103 255 How can deciper meaning ful text from it. My code is as below: import java.io.*; import java.util.*; import javax.comm.*; import javax.comm.SerialPort; import java.nio.charset.Charset; import java.nio.charset.CharsetDecoder; import java.nio.charset.CharsetEncoder; public class NFCReader3 implements Runnable, SerialPortEventListener { static CommPortIdentifier portId; static Enumeration portList; InputStream inputStream; SerialPort serialPort; Thread readThread; int i=0; public static void main(String[] args) { boolean portFound = false; String defaultPort = "COM9"; portList = CommPortIdentifier.getPortIdentifiers(); while (portList.hasMoreElements()) { portId = (CommPortIdentifier) portList.nextElement(); if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) { if (portId.getName().equals(defaultPort)) { System.out.println("Found port: "+defaultPort); portFound = true; NFCReader3 reader = new NFCReader3(); } } } if (!portFound) { System.out.println("port " + defaultPort + " not found."); } } public NFCReader3() { try { serialPort = (SerialPort) portId.open("SimpleReadApp2S", 2000); } catch (PortInUseException e) {} try { inputStream = serialPort.getInputStream(); } catch (IOException e) {} try { serialPort.addEventListener(this); } catch (TooManyListenersException e) {} serialPort.notifyOnDataAvailable(true); try { serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); } catch (UnsupportedCommOperationException e) {} readThread = new Thread(this); readThread.start(); } public void run() { try { Thread.sleep(20000); } catch (InterruptedException e) {} } public void serialEvent(SerialPortEvent event) { StringBuffer inputBuffer = new StringBuffer(); int newData = 0; switch (event.getEventType()) { case SerialPortEvent.BI: case SerialPortEvent.OE: case SerialPortEvent.FE: case SerialPortEvent.PE: case SerialPortEvent.CD: case SerialPortEvent.CTS: case SerialPortEvent.DSR: case SerialPortEvent.RI: case SerialPortEvent.OUTPUT_BUFFER_EMPTY: break; case SerialPortEvent.DATA_AVAILABLE: while (newData != -1) { try { newData = inputStream.read(); System.out.print(newData); System.out.print(" "); if (newData == -1) { break; } if ('\r' == (char)newData) { inputBuffer.append('\n'); } else { inputBuffer.append((char)newData); } } catch (IOException ex) { System.out.println("exception"); System.err.println(ex); return; } } break;

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  • Asp.NET custom templated datalist throws argument out of range (index) on button press

    - by MrTortoise
    I have a class BaseTemplate public abstract class BaseTemplate : ITemplate This adds the controls, and provides abstract methods to implement in the inheriting class. The inheriting class then adds its html according to its data source and manages the data binding. This all works fine - I get the control appearing with properly parsed html. The problem is that the base class adds controls into the template that have their own CommandName arguments; the idea is that the class that implements the custom templated dataList will provide the logic of setting the Selected and Edit Indexes. This class also manages the data binding, etc. It sets all of the templates on the datalist in the Init method (which was another cause of this exception). The exception gets thrown when I hit one of these buttons - I have tried hooking up both their click and command events everywhere in case this was the problem. I have also ensured that their command names do not match any of the system ones. The stack trace does not include any references to my methods or objects which is why I am so stuck. It is the most unhelpful message I can imagine. The really frustrating thing is that I cannot get a breakpoint to fire - i.e. the problem is happening after I click the button, but before and of my code can execute. The last time this exception happened was when I had this code in a user control and was assigning the templates to the datalist in the PageLoad. I moved these into init to fix that problem; however, this is a problem that was there then and I have no idea what is causing it let alone how to solve it (and index out of range doesn't really help without knowing what index.) The Exception Details Exception Details: System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values. Parameter name: index The Stack Trace: [ArgumentOutOfRangeException: Specified argument was out of the range of valid values. Parameter name: index] System.Web.UI.ControlCollection.get_Item(Int32 index) +8665582 System.Web.UI.WebControls.DataList.GetItem(ListItemType itemType, Int32 repeatIndex) +8667655 System.Web.UI.WebControls.DataList.System.Web.UI.WebControls.IRepeatInfoUser.GetItemStyle(ListItemType itemType, Int32 repeatIndex) +11 System.Web.UI.WebControls.RepeatInfo.RenderVerticalRepeater(HtmlTextWriter writer, IRepeatInfoUser user, Style controlStyle, WebControl baseControl) +8640873 System.Web.UI.WebControls.RepeatInfo.RenderRepeater(HtmlTextWriter writer, IRepeatInfoUser user, Style controlStyle, WebControl baseControl) +27 System.Web.UI.WebControls.DataList.RenderContents(HtmlTextWriter writer) +208 System.Web.UI.WebControls.BaseDataList.Render(HtmlTextWriter writer) +30 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134 System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19 System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) +163 System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) +32 System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) +51 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99 System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) +40 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134 System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19 System.Web.UI.Page.Render(HtmlTextWriter writer) +29 System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27 System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99 System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1266 The code Base class: public abstract class BaseTemplate : ITemplate { ListItemType _templateType; public BaseTemplate(ListItemType theTemplateType) { _templateType = theTemplateType; } public ListItemType ListItemType { get { return _templateType; } } #region ITemplate Members public void InstantiateIn(Control container) { PlaceHolder ph = new PlaceHolder(); container.Controls.Add(ph); Literal l = new Literal(); switch (_templateType) { case ListItemType.Header: { ph.Controls.Add(new LiteralControl(@"<table><tr>")); InstantiateInHeader(ph); ph.Controls.Add(new LiteralControl(@"</tr>")); break; } case ListItemType.Footer: { ph.Controls.Add(new LiteralControl(@"<tr>")); InstantiateInFooter(ph); ph.Controls.Add(new LiteralControl(@"</tr></table>")); break; } case ListItemType.Item: { ph.Controls.Add(new LiteralControl(@"<tr>")); InstantiateInItem(ph); ph.Controls.Add(new LiteralControl(@"<td>")); Button select = new Button(); select.ID = "btnSelect"; select.CommandName = "SelectRow"; select.Text = "Select"; ph.Controls.Add(select); ph.Controls.Add(new LiteralControl(@"</td>")); ph.Controls.Add(new LiteralControl(@"</tr>")); ph.DataBinding += new EventHandler(ph_DataBinding); break; } case ListItemType.AlternatingItem: { ph.Controls.Add(new LiteralControl(@"<tr>")); InstantiateInAlternatingItem(ph); ph.Controls.Add(new LiteralControl(@"<td>")); Button select = new Button(); select.ID = "btnSelect"; select.CommandName = "SelectRow"; select.Text = "Select"; ph.Controls.Add(select); ph.Controls.Add(new LiteralControl(@"</td>")); ph.Controls.Add(new LiteralControl(@"</tr>")); ph.DataBinding+=new EventHandler(ph_DataBinding); break; } case ListItemType.SelectedItem: { ph.Controls.Add(new LiteralControl(@"<tr>")); InstantiateInItem(ph); ph.Controls.Add(new LiteralControl(@"<td>")); Button edit = new Button(); edit.ID = "btnEdit"; edit.CommandName = "EditRow"; edit.Text = "Edit"; ph.Controls.Add(edit); Button delete = new Button(); delete.ID = "btnDelete"; delete.CommandName = "DeleteRow"; delete.Text = "Delete"; ph.Controls.Add(delete); ph.Controls.Add(new LiteralControl(@"</td>")); ph.Controls.Add(new LiteralControl(@"</tr>")); ph.DataBinding += new EventHandler(ph_DataBinding); break; } case ListItemType.EditItem: { ph.Controls.Add(new LiteralControl(@"<tr>")); InstantiateInEdit(ph); ph.Controls.Add(new LiteralControl(@"<td>")); Button save = new Button(); save.ID = "btnSave"; save.CommandName = "SaveRow"; save.Text = "Save"; ph.Controls.Add(save); Button cancel = new Button(); cancel.ID = "btnCancel"; cancel.CommandName = "CancelRow"; cancel.Text = "Cancel"; ph.Controls.Add(cancel); ph.Controls.Add(new LiteralControl(@"</td>")); ph.Controls.Add(new LiteralControl(@"</tr>")); ph.DataBinding += new EventHandler(ph_DataBinding); break; } case ListItemType.Separator: { InstantiateInSeperator(ph); break; } } } void ph_DataBinding(object sender, EventArgs e) { DataBindingOverride(sender, e); } /// <summary> /// the controls placed into the PlaceHolder will get wrapped in &lt;table&gt;&lt;tr&gt; &lt;/tr&gt;. I.e. you need to provide the column names wrapped in &lt;td&gt;&lt;/td&gt; tags. /// </summary> /// <param name="header"></param> public abstract void InstantiateInHeader(PlaceHolder ph); /// <summary> /// the controls will have a column added after them and so require each column to be properly wrapped in &lt;td&gt;&lt;/td&gt; tags. The &lt;tr&gt;&lt;/tr&gt; is handled in the base class. /// </summary> /// <param name="ph"></param> public abstract void InstantiateInItem(PlaceHolder ph); /// <summary> /// the controls will have a column added after them and so require each column to be properly wrapped in &lt;td&gt;&lt;/td&gt; tags. The &lt;tr&gt;&lt;/tr&gt; is handled in the base class. /// </summary> /// <param name="ph"></param> public abstract void InstantiateInAlternatingItem(PlaceHolder ph); /// <summary> /// the controls will have a column added after them and so require each column to be properly wrapped in &lt;td&gt;&lt;/td&gt; tags. The &lt;tr&gt;&lt;/tr&gt; is handled in the base class. /// </summary> /// <param name="ph"></param> public abstract void InstantiateInEdit(PlaceHolder ph); /// <summary> /// Any html used in the footer will have &lt;/tr&gt;&lt;table&gt; appended to the end. /// &lt;tr&gt; will be appended to the front. /// </summary> /// <param name="ph"></param> public abstract void InstantiateInFooter(PlaceHolder ph); /// <summary> /// the controls will have a column added after them and so require each column to be properly wrapped in &lt;td&gt;&lt;/td&gt; tags. The &lt;tr&gt;&lt;/tr&gt; is handled in the base class. /// Adds Delete and Edit Buttons after the table contents. /// </summary> /// <param name="ph"></param> public abstract void InstantiateInSelectedItem(PlaceHolder ph); /// <summary> /// The base class provides no &lt;tr&gt;&lt;/tr&gt; tags /// </summary> /// <param name="ph"></param> public abstract void InstantiateInSeperator(PlaceHolder ph); /// <summary> /// Use this method to bind the controls to their data. /// </summary> /// <param name="sender"></param> /// <param name="e"></param> public abstract void DataBindingOverride(object sender, EventArgs e); #endregion } Inheriting class: public class NominalGroupTemplate : BaseTemplate { public NominalGroupTemplate(ListItemType theListItemType) : base(theListItemType) { } public override void InstantiateInHeader(PlaceHolder ph) { ph.Controls.Add(new LiteralControl(@"<td>ID</td><td>Group</td><td>IsPositive</td>")); } public override void InstantiateInItem(PlaceHolder ph) { ph.Controls.Add(new LiteralControl(@"<td>")); Label lblID = new Label(); lblID.ID = "lblID"; ph.Controls.Add(lblID); ph.Controls.Add(new LiteralControl(@"</td><td>")); Label lblGroup = new Label(); lblGroup.ID = "lblGroup"; ph.Controls.Add(lblGroup); ph.Controls.Add(new LiteralControl(@"</td><td>")); CheckBox chkIsPositive = new CheckBox(); chkIsPositive.ID = "chkIsPositive"; chkIsPositive.Enabled = false; ph.Controls.Add(chkIsPositive); ph.Controls.Add(new LiteralControl(@"</td>")); } public override void InstantiateInAlternatingItem(PlaceHolder ph) { InstantiateInItem(ph); } public override void InstantiateInEdit(PlaceHolder ph) { ph.Controls.Add(new LiteralControl(@"<td>")); Label lblID = new Label(); lblID.ID = "lblID"; ph.Controls.Add(lblID); ph.Controls.Add(new LiteralControl(@"</td><td>")); TextBox txtGroup = new TextBox(); txtGroup.ID = "txtGroup"; txtGroup.Visible = true; txtGroup.Enabled = true ; ph.Controls.Add(txtGroup); ph.Controls.Add(new LiteralControl(@"</td><td>")); CheckBox chkIsPositive = new CheckBox(); chkIsPositive.ID = "chkIsPositive"; chkIsPositive.Visible = true; chkIsPositive.Enabled = true ; ph.Controls.Add(chkIsPositive); ph.Controls.Add(new LiteralControl(@"</td>")); } public override void InstantiateInFooter(PlaceHolder ph) { InstantiateInHeader(ph); } public override void InstantiateInSelectedItem(PlaceHolder ph) { ph.Controls.Add(new LiteralControl(@"<td>")); Label lblID = new Label(); lblID.ID = "lblID"; ph.Controls.Add(lblID); ph.Controls.Add(new LiteralControl(@"</td><td>")); TextBox txtGroup = new TextBox(); txtGroup.ID = "txtGroup"; txtGroup.Visible = true; txtGroup.Enabled = false; ph.Controls.Add(txtGroup); ph.Controls.Add(new LiteralControl(@"</td><td>")); CheckBox chkIsPositive = new CheckBox(); chkIsPositive.ID = "chkIsPositive"; chkIsPositive.Visible = true; chkIsPositive.Enabled = false; ph.Controls.Add(chkIsPositive); ph.Controls.Add(new LiteralControl(@"</td>")); } public override void InstantiateInSeperator(PlaceHolder ph) { } public override void DataBindingOverride(object sender, EventArgs e) { PlaceHolder ph = (PlaceHolder)sender; DataListItem li = (DataListItem)ph.NamingContainer; int id = Convert.ToInt32(DataBinder.Eval(li.DataItem, "ID")); string group = (string)DataBinder.Eval(li.DataItem, "Group"); bool isPositive = Convert.ToBoolean(DataBinder.Eval(li.DataItem, "IsPositive")); switch (this.ListItemType) { case ListItemType.Item: case ListItemType.AlternatingItem: { ((Label)ph.FindControl("lblID")).Text = id.ToString(); ((Label)ph.FindControl("lblGroup")).Text = group; ((CheckBox)ph.FindControl("chkIsPositive")).Text = isPositive.ToString(); break; } case ListItemType.EditItem: case ListItemType.SelectedItem: { ((TextBox)ph.FindControl("lblID")).Text = id.ToString(); ((TextBox)ph.FindControl("txtGroup")).Text = group; ((CheckBox)ph.FindControl("chkIsPositive")).Text = isPositive.ToString(); break; } } } } From here I added the control to a page the code behind public partial class NominalGroupbroke : System.Web.UI.UserControl { public void SetNominalGroupList(IList<BONominalGroup> theNominalGroups) { XElement data = Serialiser<BONominalGroup>.SerialiseObjectList(theNominalGroups); ViewState.Add("nominalGroups", data.ToString()); dlNominalGroup.DataSource = theNominalGroups; dlNominalGroup.DataBind(); } protected void Page_init() { dlNominalGroup.HeaderTemplate = new NominalGroupTemplate(ListItemType.Header); dlNominalGroup.ItemTemplate = new NominalGroupTemplate(ListItemType.Item); dlNominalGroup.AlternatingItemTemplate = new NominalGroupTemplate(ListItemType.AlternatingItem); dlNominalGroup.SeparatorTemplate = new NominalGroupTemplate(ListItemType.Separator); dlNominalGroup.SelectedItemTemplate = new NominalGroupTemplate(ListItemType.SelectedItem); dlNominalGroup.EditItemTemplate = new NominalGroupTemplate(ListItemType.EditItem); dlNominalGroup.FooterTemplate = new NominalGroupTemplate(ListItemType.Footer); } protected void Page_Load(object sender, EventArgs e) { dlNominalGroup.ItemCommand += new DataListCommandEventHandler(dlNominalGroup_ItemCommand); } void dlNominalGroup_Init(object sender, EventArgs e) { dlNominalGroup.HeaderTemplate = new NominalGroupTemplate(ListItemType.Header); dlNominalGroup.ItemTemplate = new NominalGroupTemplate(ListItemType.Item); dlNominalGroup.AlternatingItemTemplate = new NominalGroupTemplate(ListItemType.AlternatingItem); dlNominalGroup.SeparatorTemplate = new NominalGroupTemplate(ListItemType.Separator); dlNominalGroup.SelectedItemTemplate = new NominalGroupTemplate(ListItemType.SelectedItem); dlNominalGroup.EditItemTemplate = new NominalGroupTemplate(ListItemType.EditItem); dlNominalGroup.FooterTemplate = new NominalGroupTemplate(ListItemType.Footer); } void dlNominalGroup_DataBinding(object sender, EventArgs e) { } void deleteNominalGroup(int index) { XElement data = XElement.Parse(Convert.ToString( ViewState["nominalGroups"] )); IList<BONominalGroup> list = Serialiser<BONominalGroup>.DeserialiseObjectList(data); FENominalGroup.DeleteNominalGroup(list[index].ID); list.RemoveAt(index); data = Serialiser<BONominalGroup>.SerialiseObjectList(list); ViewState["nominalGroups"] = data.ToString(); dlNominalGroup.DataSource = list; dlNominalGroup.DataBind(); } void updateNominalGroup(DataListItem theItem) { XElement data = XElement.Parse(Convert.ToString( ViewState["nominalGroups"])); IList<BONominalGroup> list = Serialiser<BONominalGroup>.DeserialiseObjectList(data); BONominalGroup old = list[theItem.ItemIndex]; BONominalGroup n = new BONominalGroup(); byte id = Convert.ToByte(((TextBox)theItem.FindControl("lblID")).Text); string group = ((TextBox)theItem.FindControl("txtGroup")).Text; bool isPositive = Convert.ToBoolean(((CheckBox)theItem.FindControl("chkIsPositive")).Text); n.ID = id; n.Group = group; n.IsPositive = isPositive; FENominalGroup.UpdateNominalGroup(old, n); list[theItem.ItemIndex] = n; data = Serialiser<BONominalGroup>.SerialiseObjectList(list); ViewState["nominalGroups"] = data.ToString(); } void dlNominalGroup_ItemCommand(object source, DataListCommandEventArgs e) { DataList l = (DataList)source; switch (e.CommandName) { case "SelectRow": { if (l.EditItemIndex == -1) { l.SelectedIndex = e.Item.ItemIndex; l.EditItemIndex = -1; } break; } case "EditRow": { if (l.SelectedIndex == e.Item.ItemIndex) { l.EditItemIndex = e.Item.ItemIndex; } break; } case "DeleteRow": { deleteNominalGroup(e.Item.ItemIndex); l.EditItemIndex = -1; try { l.SelectedIndex = e.Item.ItemIndex; } catch { l.SelectedIndex = -1; } break; } case "CancelRow": { l.SelectedIndex = l.EditItemIndex; l.EditItemIndex = -1; break; } case "SaveRow": { updateNominalGroup(e.Item); try { l.SelectedIndex = e.Item.ItemIndex; } catch { l.SelectedIndex = -1; } l.EditItemIndex = -1; break; } } } Lots of code there, I'm afraid, but it should build. Thanks if anyone manages to spot my silliness. The BONominalGroup class (please ignore my crazy getHash override, I'm not proud of it). IAudit can just be an empty interface here and all will be fine. It used to inherit from another class, I have cleaned that out - so the serialization logic may be broken here. public class BONominalGroup { public BONominalGroup() #region Fields and properties private Int16 _ID; public Int16 ID { get { return _ID; } set { _ID = value; } } private string _group; public string Group { get { return _group; } set { _group = value; } } private bool _isPositve; public bool IsPositive { get { return _isPositve; } set { _isPositve = value; } } #endregion public override bool Equals(object obj) { bool retVal = false; BONominalGroup ng = obj as BONominalGroup; if (ng!=null) if (ng._group == this._group && ng._ID == this.ID && ng.IsPositive == this.IsPositive) { retVal = true; } return retVal; } public override int GetHashCode() { return ToString().GetHashCode(); } public override string ToString() { return "BONominalGroup{ID:" + this.ID.ToString() + ",Group:" + this.Group.ToString() + ",IsPositive:" + this.IsPositive.ToString() + "," + "}"; } #region IXmlSerializable Members public override void ReadXml(XmlReader reader) { reader.ReadStartElement("BONominalGroup"); this.ID = Convert.ToByte(reader.ReadElementString("id")); this.Group = reader.ReadElementString("group"); this.IsPositive = Convert.ToBoolean(reader.ReadElementString("isPositive")); base.ReadXml(reader); reader.ReadEndElement(); } public override void WriteXml(XmlWriter writer) { writer.WriteElementString("id", this.ID.ToString()); writer.WriteElementString("group", this.Group); writer.WriteElementString("isPositive", this.IsPositive.ToString()); // writer.WriteStartElement("BOBase"); // base.WriteXml(writer); writer.WriteEndElement(); } #endregion }

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  • Worse is better. Is there an example?

    - by J.F. Sebastian
    Is there a widely-used algorithm that has time complexity worse than that of another known algorithm but it is a better choice in all practical situations (worse complexity but better otherwise)? An acceptable answer might be in a form: There are algorithms A and B that have O(N**2) and O(N) time complexity correspondingly, but B has such a big constant that it has no advantages over A for inputs less then a number of atoms in the Universe. Examples highlights from the answers: Simplex algorithm -- worst-case is exponential time -- vs. known polynomial-time algorithms for convex optimization problems. A naive median of medians algorithm -- worst-case O(N**2) vs. known O(N) algorithm. Backtracking regex engines -- worst-case exponential vs. O(N) Thompson NFA -based engines. All these examples exploit worst-case vs. average scenarios. Are there examples that do not rely on the difference between the worst case vs. average case scenario? Related: The Rise of ``Worse is Better''. (For the purpose of this question the "Worse is Better" phrase is used in a narrower (namely -- algorithmic time-complexity) sense than in the article) Python's Design Philosophy: The ABC group strived for perfection. For example, they used tree-based data structure algorithms that were proven to be optimal for asymptotically large collections (but were not so great for small collections). This example would be the answer if there were no computers capable of storing these large collections (in other words large is not large enough in this case). Coppersmith–Winograd algorithm for square matrix multiplication is a good example (it is the fastest (2008) but it is inferior to worse algorithms). Any others? From the wikipedia article: "It is not used in practice because it only provides an advantage for matrices so large that they cannot be processed by modern hardware (Robinson 2005)."

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