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• Consolidating coding styles: Funcs, private method, single method classes

  - by jdoig

  Hi all, We currently have 3 devs with, some, conflicting styles and I'm looking for a way to bring peace to the kingdom... The Coders: Foo 1: Likes to use Func's & Action's inside public methods. He uses actions to alias off lengthy method calls and Func's to perform simple tasks that can be expressed in 1 or 2 lines and will be used frequently through out the code Pros: The main body of his code is succinct and very readable, often with only one or 2 public methods per class and rarely any private methods. Cons: The start of methods contain blocks of lambda rich code that other developers don't enjoy reading; and, on occasion, can contain higher order functions that other dev's REALLY don't like reading. Foo 2: Likes to create a private method for (almost) everything the public method will have to do . Pros: Public methods remain small and readable (to all developers). Cons: Private methods are numerous. With private methods that call into other private methods, that call into... etc, etc. Making code hard to navigate. Foo 3: Likes to create a public class with a, single, public method for every, non-trivial, task that needs performing, then dependency inject them into other objects. Pros: Easily testable, easy to understand (one object, one responsibility). Cons: project gets littered by classes, opening multiple class files to understand what code does makes navigation awkward. It would be great to take the best of all these techniques... Foo-1 Has really nice, readable (almost dsl-like) code... for the most part, except for all the Action and Func lambda shenanigans bulked together at the start of a method. Foo-3 Has highly testable and extensible code that just feels a bit "belt-&-braces" for some solutions and has some code-navigation niggles (constantly hitting F12 in VS and opening 5 other .cs files to find out what a single method does). And Foo-2... Well I'm not sure I like anything about the one-huge .cs file with 2 public methods and 12 private ones, except for the fact it's easier for juniors to dig into. I admit I grossly over-simplified the explanations of those coding styles; but if any one knows of any patterns, practices or diplomatic-manoeuvres that can help unite our three developers (without just telling any of them to just "stop it!") that would be great. From a feasibility standpoint : Foo-1's style meets with the most resistance due to some developers finding lambda and/or Func's hard to read. Foo-2's style meets with a less resistance as it's just so easy to fall into. Foo-3's style requires the most forward thinking and is difficult to enforce when time is short. Any ideas on some coding styles or conventions that can make this work?

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• Actionscript base class in Flex AIR app

  - by Alan

  I'm trying to build a Flex AIR app using Flex Builder 3, which I'm just getting started with. In Flash CS4, there's a text field in the authoring environment where you can specify a class that will become the "base" class - your class inherits from Sprite and then "becomes" the Stage at runtime. Is there a a way to do the same thing with Flex/AIR? Failing that, can anyone explain how to create and use an external class? Originally I had this in TestApp.mxml: <?xml version="1.0" encoding="utf-8"?> <mx:WindowedApplication xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"> <mx:Script source="TestApp.as"/> </mx:WindowedApplication> And this in TestApp.as: package { public class TestApp { public function TestApp() { trace('Hello World'); } } } That gives the error "packages cannot be nested", so I tried taking out the package statement: public class TestApp { public function TestApp() { trace('Hello World'); } } That gives an error "classes cannot be nested", so I finally gave up and tried to take out the class altogether, figuring I'd try to start with a bunch of functions instead: function init() { trace('Hello World'); } But that gives the error "A file found in a source-path must have an externally visible definition. If a definition in the file is meant to be externally visible, please put the definition in a package". I can't win! When I put my class in a package, it says I can't do that because it would be nested. When I don't, it says it needs to be in a package so it can be seen. Does anyone know how to fix this? If I can't do the custom-class-as-base-class thing, is there a way I could just have it like: <?xml version="1.0" encoding="utf-8"?> <mx:WindowedApplication xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"> <mx:Script source="TestApp.as"/> <mx:Script> var app = new TestApp(); </mx:Script> </mx:WindowedApplication> At the moment I can't import the class definition at all, so even that won't work. Thanks in advance!

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• MATLAB: different function returns from command line and within function

  - by Myx

  Hello: I have an extremely bizzare situation: I have a function in MATLAB which calls three other main functions and produces two figures for me. The function reads in an input jpeg image, crops it, segments it using kmeans clustering, and outputs 2 figures to the screen - the original image and the clustered image with the cluster centers indicated. Here is the function in MATLAB: function [textured_avg_x photo_avg_x] = process_database_images() clear all warning off %#ok type_num_max = 3; % type is 1='texture', 2='graph', or 3='photo' type_num_max = 1; img_max_num_photo = 100; % 400 photo images img_max_num_other = 100; % 100 textured, and graph images for type_num = 1:2:type_num_max if(type_num == 3) img_num_max = img_max_num_photo; else img_num_max = img_max_num_other; end img_num_max = 1; for img_num = 1:img_num_max [type img] = load_image(type_num, img_num); %img = imread('..\images\445.jpg'); img = crop_image(img); [IDX k block_bounds features] = segment_image(img); end end end The function segment_image first shows me the color image that was passed in, performs kmeans clustering, and outputs the clustered image. When I run this function on a particular image, I get 3 clusters (which is not what I expect to get). When I run the following commands from the MATLAB command prompt: >> img = imread('..\images\texture\1.jpg'); >> img = crop_image(img); >> segment_image(img); then the first image that is displayed by segment_image is the same as when I run the function (so I know that the clustering is done on the same image) but the number of clusters is 16 (which is what I expect). In fact, when I run my process_database_images() function on my entire image database, EVERY image is evaluated to have 3 clusters (this is a problem), whereas when I test some images individually, I get in the range of 12-16 clusters, which is what I prefer and expect. Why is there such a discrepancy? Am I having some syntax bug in my process_database_images() function? If more code is required from me (i.e. segment_images function, or crop_image function), please let me know. Thanks.

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• Bracketing algorithm when root finding. Single root in "quadratic" function

  - by Ander Biguri

  I am trying to implement a root finding algorithm. I am using the hybrid Newton-Raphson algorithm found in numerical recipes that works pretty nicely. But I have a problem in bracketing the root. While implementing the root finding algorithm I realised that in several cases my functions have 1 real root and all the other imaginary (several of them, usually 6 or 9). The only root I am interested is in the real one so the problem is not there. The thing is that the function approaches the root like a cubic function, touching with the point the y=0 axis... Newton-Rapson method needs some brackets of different sign and all the bracketing methods I found don't work for this specific case. What can I do? It is pretty important to find that root in my program... EDIT: more problems: sometimes due to reaaaaaally small numerical errors, say a variation of 1e-6 in some value the "cubic" function does NOT have that real root, it is just imaginary with a neglectable imaginary part... (checked with matlab) EDIT 2: Much more information about the problem. Ok, I need root finding algorithm. Info I have: The root I need to find is between [0-1] , if there are more roots outside that part I am not interested in them. The root is real, there may be imaginary roots, but I don't want them. Probably all the rest of the roots will be imaginary The root may be double in that point, but I think that actually doesn't mater in numerical analysis problems I need to use the root finding algorithm several times during the overall calculations, but the function will always be a polynomial In one of the particular cases of the root finding, my polynomial will be similar to a quadratic function that touches Y=0 with the point. Example of a real case: The coefficient may not be 100% precise and that really slight imprecision may make the function not to touch the Y=0 axis. I cannot solve for this specific case because in other cases it may be that the polynomial is pretty normal and doesn't make any "strange" thing. The method I am actually using is NewtonRaphson hybrid, where if the derivative is really small it makes a bisection instead of NewRaph (found in numerical recipes). Matlab's answer to the function on the image: roots: 0.853553390593276 + 0.353553390593278i 0.853553390593276 - 0.353553390593278i 0.146446609406726 + 0.353553390593273i 0.146446609406726 - 0.353553390593273i 0.499999999999996 + 0.000000040142134i 0.499999999999996 - 0.000000040142134i The function is a real example I prepared where I know that the answer I want is 0.5 Note: I still haven't check completely some of the answers I you people have give me (Thank you!), I am just trying to give al the information I already have to complete the question.

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• Display an Image using C# in Web Application

  - by Josh

  Hello again, I have a Web Application that I built a C# class in that generates a Report. This report takes nearly 40 seconds to generate because it searches hundreds of folders for certain files. So I was hoping there was a way to display a "Loading.." icon as this report is generating. I have a gif stored in my Images folder that would be perfect. The research that I've done at this point mostly talks about picturebox's and image controls that can hold the image but I was hoping there was just a way of displaying the image above the report while its being created. The Web Application is from a Web ADF Geocortex website and again I created a C# class that generates this report. Below is some code that may help. /// <summary> /// Generates HTML for the current report using the data in /// the given table. /// </summary> /// <param name="reportLayers">The layers to include in the report.</param> /// <returns> public override string GenerateReportHtml(List<ReportLayer> reportLayers) { StringBuilder htmlString = new StringBuilder(); StringWriter stringWriter = new StringWriter(htmlString); HtmlTextWriter writer = new HtmlTextWriter(stringWriter); string holdAPI = ""; List<string> exclusions = GetExcludedFields(); foreach (ReportLayer layer in reportLayers) { string[] strFiles = null; Boolean val = false; if (layer.Layer.Name == "Bottom Hole Location (OP)") writer.RenderBeginTag(HtmlTextWriterTag.P); // <p> writer.RenderBeginTag(HtmlTextWriterTag.Strong); // <strong> writer.Write(layer.Layer.Name); writer.RenderEndTag(); // end </strong> writer.RenderEndTag(); // end </p> writer.WriteBreak(); // <br /> foreach (ReportFeature feature in layer.ReportFeatures) { // each feature will be in a table writer.RenderBeginTag(HtmlTextWriterTag.Table); // <table> foreach (ReportField field in feature.ReportFields) { string fieldName = field.Alias; if (!exclusions.Contains(fieldName)) {

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• Abstract Data Type: Any1 can help me this? thanks..

  - by Aga Hibaya

  Objectives: Implement the Abstract Data Type (ADT) List using dynamically allocated arrays and structures. Description A LIST is an ordered collection of items where items may be inserted anywhere in the list. Implement a LIST using an array as follows: struct list { int *items; // pointer to the array int size; // actual size of the array int count; // number of items in the array }; typedef struct list *List; // pointer to the structure Implement the following functions: a) List newList(int size); - will create a new List and return its pointer. Allocate space for the structure, allocate space for the array, then initialize size and count, return the pointer. b) void isEmpty(List list); c) void display(List list); d) int contains(List list, int item); e) void remove(List list, int i) ; f) void insertAfter(List list,int item, int i); g) void addEnd(List list,int item) - add item at the end of the list – simply store the data at position count, then increment count. If the array is full, allocate an array twice as big as the original. count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 addEnd(list,40) will result to count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 40 h) void addFront(List list,int item) - shift all elements to the right so that the item can be placed at position 0, then increment count. Bonus: if the array is full, allocate an array twice as big as the original. count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 addFront(list,40) will result to count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 10 15 20 30 i) void removeFront(List list) - shift all elements to the left and decrement count; count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 10 15 20 30 removeFront(list) will result to count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 j) void remove(List list,int item) - get the index of the item in the list and then shift all elements to the count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 10 15 20 30 remove(list,10) will result to count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 15 20 30 Remarks

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• Mocking a concrete class : templates and avoiding conditional compilation

  - by AshirusNW

  I'm trying to testing a concrete object with this sort of structure. class Database { public: Database(Server server) : server_(server) {} int Query(const char* expression) { server_.Connect(); return server_.ExecuteQuery(); } private: Server server_; }; i.e. it has no virtual functions, let alone a well-defined interface. I want to a fake database which calls mock services for testing. Even worse, I want the same code to be either built against the real version or the fake so that the same testing code can both: Test the real Database implementation - for integration tests Test the fake implementation, which calls mock services To solve this, I'm using a templated fake, like this: #ifndef INTEGRATION_TESTS class FakeDatabase { public: FakeDatabase() : realDb_(mockServer_) {} int Query(const char* expression) { MOCK_EXPECT_CALL(mockServer_, Query, 3); return realDb_.Query(); } private: // in non-INTEGRATION_TESTS builds, Server is a mock Server with // extra testing methods that allows mocking Server mockServer_; Database realDb_; }; #endif template <class T> class TestDatabaseContainer { public: int Query(const char* expression) { int result = database_.Query(expression); std::cout << "LOG: " << result << endl; return result; } private: T database_; }; Edit: Note the fake Database must call the real Database (but with a mock Server). Now to switch between them I'm planning the following test framework: class DatabaseTests { public: #ifdef INTEGRATION_TESTS typedef TestDatabaseContainer<Database> TestDatabase ; #else typedef TestDatabaseContainer<FakeDatabase> TestDatabase ; #endif TestDatabase& GetDb() { return _testDatabase; } private: TestDatabase _testDatabase; }; class QueryTestCase : public DatabaseTests { public: void TestStep1() { ASSERT(GetDb().Query(static_cast<const char *>("")) == 3); return; } }; I'm not a big fan of that compile-time switching between the real and the fake. So, my question is: Whether there's a better way of switching between Database and FakeDatabase? For instance, is it possible to do it at runtime in a clean fashion? I like to avoid #ifdefs. Also, if anyone has a better way of making a fake class that mimics a concrete class, I'd appreciate it. I don't want to have templated code all over the actual test code (QueryTestCase class). Feel free to critique the code style itself, too. You can see a compiled version of this code on codepad.

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• Magento: add product twice to cart, with different attributes!

  - by Peter

  Hello all, i have been working with this for a whole day but i cannot find any solution: I have a product (lenses), which has identical attributes, but user can choose one attribute set for one eye and another attribute set for another. On the frontend i got it ok, see it here: http://connecta.si/clarus/index.php/featured/acuvue-oasys-for-astigmatism.html So the user can select attributes for left or right eye, but it is the same product. I build a function, wich should take a product in a cart (before save), add other set of attributes, so there should be two products in the cart. What happens is there are two products, but with the same set of attributes??? Here is the snippet of the function: $req = Mage::app()-getRequest(); $request[’qty’] = 1; $request[’product’] = 15; $request[’uenc’] = $req-get(’uenc’); $request[’options’][1] = 1; $request[’options’][3] = 5; $request[’options’][2] = 3; $reqo = new Varien_Object($request); $newitem = $quote-addProduct($founditem-getProduct(), $reqo); //add another one ------------------------------------------ $request[’qty’] = 1; $request[’product’] = 15; $request[’uenc’] = $req-get(’uenc’); $request[’options’][1] = 2; $request[’options’][3] = 6; $request[’options’][2] = 4; $reqo = new Varien_Object($request); $newitem = $quote-addProduct($founditem-getProduct(), $reqo); Or another test, with some other functions (again, product added, with 2 quantity , but same attributes...): $req = Mage::app()-getRequest(); $request[’qty’] = 1; $request[’product’] = 15; $request[’uenc’] = $req-get(’uenc’); $request[’options’][1] = 2; $request[’options’][3] = 6; $request[’options’][2] = 4; $product = $founditem-getProduct(); $cart = Mage::getSingleton(’checkout/cart’); //delete all first… $cart-getItems()-clear()-save(); $reqo = new Varien_Object($request); $cart-addProduct($founditem-getProduct(), $reqo); $cart-getItems()-save(); $request[’options’][1] = 1; $request[’options’][3] = 5; $request[’options’][2] = 3; $reqo = new Varien_Object($request); $cart-addProduct($founditem-getProduct(), $reqo); $cart-getItems()-save(); i really dont know what more to do, please any advice, this is my first module in magento… thank you, Peter

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• Inserting contact with android and querying the result uri returns no entries

  - by th0m4d

  Im developing an application which is dealing with the android contacts API. I implemented methods to insert, update and query contacts. So far everything worked (writing and reading contacts). At one point in my project Im experiencing a strange behaviour. I insert a contact using batch mode. I receive the URI to the RawContact. I do this in a background thread. // use batchmode for contact insertion ArrayList ops = new ArrayList(); int rawContactInsertIndex = ops.size(); // create rawContact ops.add(ContentProviderOperation.newInsert(RawContacts.CONTENT_URI) .withValue(RawContacts.ACCOUNT_TYPE, ConstantsContract.ACCOUNT_TYPE) .withValue(RawContacts.ACCOUNT_NAME, accountName).build()); ops.add(createInsertOperation().withValueBackReference(Data.RAW_CONTACT_ID, rawContactInsertIndex) .withValue(Data.MIMETYPE, StructuredName.CONTENT_ITEM_TYPE) .withValue(StructuredName.DISPLAY_NAME, displayName).withValue(StructuredName.GIVEN_NAME, firstName) .withValue(StructuredName.FAMILY_NAME, lastName).build()); //other data values... ContentProviderResult[] results = context.getContentResolver().applyBatch(ContactsContract.AUTHORITY, ops); if (results.length 0) { result = results[0]; } Then i request and store the lookup uri RawContacts.getContactLookupUri(this.getContentResolver(), myContantRawContactUri); I am able to query the contact using the rawContactUri directly after inserting it (in the same thread). The lookup uri returns null. Uri rawContactUri = appUser.getRawContactUri(ctx); if (rawContactUri == null) { return null; } String lastPathSegment = rawContactUri.getLastPathSegment(); long rawContactId = Long.decode(lastPathSegment); if (rawContactUri != null) { contact = readContactWithID(rawContactId, ContactsContract.Data.RAW_CONTACT_ID); In a different place in the project I want to query the contact i inserted by the stored lookup uri or raw contact uri. Both return no rows from the content provider. I tried it in the main thread and in another background thread. ctx.getContentResolver().query(ContactsContract.Data.CONTENT_URI, null, ContactsContract.Data.RAW_CONTACT_ID + " = ? AND " + ContactsContract.Data.MIMETYPE + " = ?", new String[] { contactID + "", ContactsContract.CommonDataKinds.StructuredName.CONTENT_ITEM_TYPE }, null); My first thought was that it could be related to the context.getContentResolver(). But the android documentation states, that the ContentResolver objects scope is the application's package, so you have on ContentResolver for the whole app. Am I right? What am I doing wrong? Why does the same rawContactUri return the contact at one place and does not on another place? And why do I get a lookup uri from a raw contact, which is not working at all?

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• service broker message process order

  - by Blootac

  Everywhere I read says that messages handled by the service broker are processed in the order that they arrive, and yet if you create a table, message type, contract, service etc , and on activation have a stored proc that waits for 2 seconds and inserts the msg into a table, set the max queue readers to 5 or 10, and send 20 odd messages I can see in the table that they are inserted out of order even though when I insert them into the queue and look at the contents of the queue I can see that the messages are all in the right order. Is it due to the delay waitfor waiting for the nearest second and each thread having different subsecond times and then fighting for a lock or something? The reason i've got a delay in there is to simulate delays with joins etc Thanks demo code: --create the table and service broker CREATE TABLE test ( id int identity(1,1), contents varchar(100) ) CREATE MESSAGE TYPE test CREATE CONTRACT mycontract ( test sent by initiator ) GO CREATE PROCEDURE dostuff AS BEGIN DECLARE @msg varchar(100); RECEIVE TOP (1) @msg = message_body FROM myQueue IF @msg IS NOT NULL BEGIN WAITFOR DELAY '00:00:02' INSERT INTO test(contents)values(@msg) END END GO ALTER QUEUE myQueue WITH STATUS = ON, ACTIVATION ( STATUS = ON, PROCEDURE_NAME = dostuff, MAX_QUEUE_READERS = 10, EXECUTE AS SELF ) create service senderService on queue myQueue ( mycontract ) create service receiverService on queue myQueue ( mycontract ) GO --********************************************************** --now insert lots of messages to the queue DECLARE @dialog_handle uniqueidentifier BEGIN DIALOG @dialog_handle FROM SERVICE senderService TO SERVICE 'receiverService' ON CONTRACT mycontract; SEND ON CONVERSATION @dialog_handle MESSAGE TYPE test ('<test>1</test>'); BEGIN DIALOG @dialog_handle FROM SERVICE senderService TO SERVICE 'receiverService' ON CONTRACT mycontract; SEND ON CONVERSATION @dialog_handle MESSAGE TYPE test ('<test>2</test>') BEGIN DIALOG @dialog_handle FROM SERVICE senderService TO SERVICE 'receiverService' ON CONTRACT mycontract; SEND ON CONVERSATION @dialog_handle MESSAGE TYPE test ('<test>3</test>') BEGIN DIALOG @dialog_handle FROM SERVICE senderService TO SERVICE 'receiverService' ON CONTRACT mycontract; SEND ON CONVERSATION @dialog_handle MESSAGE TYPE test ('<test>4</test>') BEGIN DIALOG @dialog_handle FROM SERVICE senderService TO SERVICE 'receiverService' ON CONTRACT mycontract; SEND ON CONVERSATION @dialog_handle MESSAGE TYPE test ('<test>5</test>') BEGIN DIALOG @dialog_handle FROM SERVICE senderService TO SERVICE 'receiverService' ON CONTRACT mycontract; SEND ON CONVERSATION @dialog_handle MESSAGE TYPE test ('<test>6</test>') BEGIN DIALOG @dialog_handle FROM SERVICE senderService TO SERVICE 'receiverService' ON CONTRACT mycontract; SEND ON CONVERSATION @dialog_handle MESSAGE TYPE test ('<test>7</test>')

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• Collision point of 2 curves in a 3d-room

  - by Frank

  Hello, i am programming a small game for quite some time. We started coding a small FPS-Shooter inside of a project at school to get a bit experience using directX. I dont know why, but i couldnt stop the project and started programming at home aswell. At the moment i am trying to create some small AI. Of cause thats definatlly not easy, but thats my personal goal anyways. The topic could prolly fill multiple books hehe. I've got the walking part of my bots done so far. They walk along a scriped path. I am not working on the "aiming" of the bots. While programming that i hit on some math problem i couldnt solve yet. I hope of your input on this to help me get further. Concepts, ideas and everything else are highly appreciated. Problem: Calculate the position (D3DXVECTOR3) where the curve of the projectile (depends on gravity, speed), hit the curved of the enemys walking path (depends on speed). We assume that the enemy walks in a constant line. Known variables: float projectilSpeed = 2000 m/s //speed of the projectile per second float gravitation = 9.81 m/s^2 //of cause the gravity lol D3DXVECTOR3 targetPosition //position of the target stored in a vector (x,y,z) D3DXVECTOR3 projectilePosition //position of the projectile D3DXVECTOR3 targetSpeed //stores the change of the targets position in the last second Variabledefinition ProjectilePosition at time of collision = ProjectilePos_t TargetPosition at time of collision = TargetPos_t ProjectilePosition at time 0, now = ProjectilePos_0 TargetPosition at time 0, now = TargetPos_0 Time to impact = t Aim-angle = theta My try: Found a formular to calculate "drop" (Drop of the projectile based on the gravity) on Wikipedia: float drop = 0.5f * gravity * t * t The speed of the projectile has a horizontal and a vertical part.. Found a formular for that on wikipedia aswell: ProjectilVelocity.x = projectilSpeed * cos(theta) ProjectilVelocity.y = projectilSpeed * sin(theta) So i would assume this is true for the projectile curve: ProjectilePos_t.x = ProjectilePos_0.x + ProjectileSpeed * t ProjectilePos_t.y = ProjectilePos_0.y + ProjectileSpeed * t + 0.5f * gravity * t * t ProjectilePos_t.z = ProjectilePos_0.z + ProjectileSpeed * t The target walk with a constant speed, so we can determine his curve by this: TargetPos_t = TargetPos_0 + TargetSpeed * D3DXVECTOR3(t, t, t) Now i dont know how to continue. I have to solve it somehow to get a hold on the time to impact somehow. As a basic formular i could use: float time = distanz / projectileSpeed But that wouldnt be truly correct as it would assume a linear "Trajectory". We just find this behaivor when using a rocket. I hope i was able to explain the problem as much as possible. If there are questions left, feel free to ask me! Greets from germany, Frank

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• Retrieving/Updating Entity Framework POCO objects that already exist in the ObjectContext

  - by jslatts

  I have a project using Entity Framework 4.0 with POCOs (data is stored in SQL DB, lazyloading is enabled) as follows: public class ParentObject { public int ID {get; set;} public virtual List<ChildObject> children {get; set;} } public class ChildObject { public int ID {get; set;} public int ChildRoleID {get; set;} public int ParentID {get; set;} public virtual ParentObject Parent {get; set;} public virtual ChildRoleObject ChildRole {get; set;} } public class ChildRoleObject { public int ID {get; set;} public string Name {get; set;} public virtual List<ChildObject> children {get; set;} } I want to create a new ChildObject, assign it a role, then add it to an existing ParentObject. Afterwards, I want to send the new ChildObject to the caller. The code below works fine until it tries to get the object back from the database. The newChildObjectInstance only has the ChildRoleID set and does not contain a reference to the actual ChildRole object. I try and pull the new instance back out of the database in order to populate the ChildRole property. Unfortunately, in this case, instead of creating a new instance of ChildObject and assigning it to retreivedChildObject, EF finds the existing ChildObject in the context and returns the in-memory instance, with a null ChildRole property. public ChildObject CreateNewChild(int id, int roleID) { SomeObjectContext myRepository = new SomeObjectContext(); ParentObject parentObjectInstance = myRepository.GetParentObject(id); ChildObject newChildObjectInstance = new ChildObject() { ParentObject = parentObjectInstance, ParentID = parentObjectInstance.ID, ChildRoleID = roleID }; parentObjectInstance.children.Add(newChildObjectInstance); myRepository.Save(); ChildObject retreivedChildObject = myRepository.GetChildObject(newChildObjectInstance.ID); string assignedRoleName = retreivedChildObject.ChildRole.Name; //Throws exception, ChildRole is null return retreivedChildObject; } I have tried setting MergeOptions to Overwrite, calling ObjectContext.Refresh() and ObjectContext.DetectChanges() to no avail... I suspect this is related to the proxy objects that EF injects when working with POCOs. Has anyone run into this issue before? If so, what was the solution?

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• How do I get the next token in a Cstring if I want to use it as an int? (c++)

  - by Van

  My objective is to take directions from a user and eventually a text file to move a robot. The catch is that I must use Cstrings(such as char word[];) rather than the std::string and tokenize them for use. the code looks like this: void Navigator::manualDrive() { char uinput[1]; char delim[] = " "; char *token; cout << "Enter your directions below: \n"; cin.ignore(); cin.getline (uinput, 256); token=strtok(uinput, delim); if(token == "forward") { int inches; inches=token+1; travel(inches); } } I've never used Cstrings I've never tokenized anything before, and I don't know how to write this. Our T.A.'s expect us to google and find all the answers because they are aware we've never been taught these methods. Everyone in my lab is having much more trouble than usual. I don't know the code to write but I know what I want my program to do. I want it to execute like this: 1) Ask for directions. 2) cin.getline the users input 3) tokenize the inputed string 4) if the first word token == "forward" move to the next token and find out how many inches to move forward then move forward 5) else if the first token == "turn" move to the next token. if the next token == "left" move to the next token and find out how many degrees to turn left I will have to do this for forward x, backward x, turn left x, turn right x, and stop(where x is in inches or degrees). I already wrote functions that tell the robot how to move forward an inch and turn in degrees. I just need to know how to convert the inputted strings to all lowercase letters and move from token to token and convert or extract the numbers from the string to use them as integers. If all is not clear you can read my lab write up at this link: http://www.cs.utk.edu/~cs102/robot_labs/Lab9.html If anything is unclear please let me know, and I will clarify as best I can.

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• Classes to Entities; Like-class inheritence problems

  - by Stacey

  Beyond work, some friends and I are trying to build a game of sorts; The way we structure some of it works pretty well for a normal object oriented approach, but as most developers will attest this does not always translate itself well into a database persistent approach. This is not the absolute layout of what we have, it is just a sample model given for sake of representation. The whole project is being done in C# 4.0, and we have every intention of using Entity Framework 4.0 (unless Fluent nHibernate can really offer us something we outright cannot do in EF). One of the problems we keep running across is inheriting things in database models. Using the Entity Framework designer, I can draw the same code I have below; but I'm sure it is pretty obvious that it doesn't work like it is expected to. To clarify a little bit; 'Items' have bonuses, which can be of anything. Therefore, every part of the game must derive from something similar so that no matter what is 'changed' it is all at a basic enough level to be hooked into. Sounds fairly simple and straightforward, right? So then, we inherit everything that pertains to the game from 'Unit'. Weights, Measures, Random (think like dice, maybe?), and there will be other such entities. Some of them are similar, but in code they will each react differently. We're having a really big problem with abstracting this kind of thing into a database model. Without 'Enum' support, it is proving difficult to translate into multiple tables that still share a common listing. One solution we've depicted is to use a 'key ring' type approach, where everything that attaches to a character is stored on a 'Ring' with a 'Key', where each Key has a Value that represents a type. This works functionally but we've discovered it becomes very sluggish and performs poorly. We also dislike this approach because it begins to feel as if everything is 'dumped' into one class; which makes management and logical structure difficult to adhere to. I was hoping someone else might have some ideas on what I could do with this problem. It's really driving me up the wall; To summarize; the goal is to build a type (Unit) that can be used as a base type (Table per Type) for generic reference across a relatively global scope, without having to dump everything into a single collection. I can use an Interface to determine actual behavior so that isn't too big of an issue. This is 'roughly' the same idea expressed in the Entity Framework.

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• Difficulty adding widgets to django form.

  - by codingJoe

  I have a django app that tracks activities that can benefit a classroom. Using the django examples, I was able to build a form to enter this data. But when I try to add widgets to that form, things get tricky. What I want is a calendar widget that lets the user enter the 'activity_date' field using a widget. If I use Admin interface. The AdminDateWidget works fine. however. This particular user isn't allowed access to the admin interface so I need a different way to present this widget. Also I couldn't figure out how to make the bring the admin widget over into non-admin pages. So I tried a custom widget. This is the first custom widget I've built, so I'm not quite sure what is supposed to be going on here. Any Expert Advice? How do I get my date widget to work? # The Model class Activity(models.Model): activity_date = models.DateField() activity_type = models.CharField(max_length=50, choices=ACTIVITY_TYPES) activity_description = models.CharField(max_length=200) activity_duration= models.DecimalField(decimal_places=2, max_digits=4) est_attendance = models.IntegerField("Estimated attendance") # The Form class ActivityForm(forms.ModelForm): # The following line causes lockup if enabled. # With the DateTimeWidget removed, the form functions correctly except that there is no widget. #activity_date = forms.DateField(label=_('Date'), widget=DateTimeWidget) ##!!! Point of Error !!! class Meta: model = Activity fields = ('activity_date', 'activity_type', 'activity_description', 'activity_duration', 'est_attendance') def __init__(self, *args, **kwargs): super(ActivityForm, self).__init__(*args, **kwargs) instance = getattr(self, 'instance', None) edit_aid = kwargs.get('edit_aid', False) # On a different approach, the following also didn't work. #self.fields['activity_date'].widget = widgets.AdminDateWidget() # The Widget # Example referenced: http://djangosnippets.org/snippets/391/ calbtn = u""" <button id="calendar-trigger">...</button> <img src="%s/site_media/images/icon_calendar.gif" alt="calendar" id="%s_btn" style="cursor: pointer; border: 1px solid #8888aa;" title="Select date and time" onmouseover="this.style.background='#444444';" onmouseout="this.style.background=''" /> <script type="text/javascript"> Calendar.setup({ trigger : "calendar-trigger", inputField : "%s" }); </script>""" class DateTimeWidget(forms.widgets.TextInput): dformat = '%Y-%m-%d %H:%M' def render(self, name, value, attrs=None): print "DTWgt render name=%s, value=%s" % name, value if value is None: value = '' final_attrs = self.build_attrs(attrs, type=self.input_type, name=name) if value != '': try: final_attrs['value'] = \ force_unicode(value.strftime(self.dformat)) except: final_attrs['value'] = \ force_unicode(value) if not final_attrs.has_key('id'): final_attrs['id'] = u'%s_id' % (name) id = final_attrs['id'] jsdformat = self.dformat #.replace('%', '%%') cal = calbtn % (settings.MEDIA_URL, id, id, jsdformat, id) a = u'<input%s />%s' % (forms.util.flatatt(final_attrs), cal) print "render return %s " % a return mark_safe(a) def value_from_datadict(self, data, files, name): print "DTWgt value_from_datadict" dtf = forms.fields.DEFAULT_DATETIME_INPUT_FORMATS empty_values = forms.fields.EMPTY_VALUES value = data.get(name, None) if value in empty_values: return None if isinstance(value, datetime.datetime): return value if isinstance(value, datetime.date): return datetime.datetime(value.year, value.month, value.day) for format in dtf: try: return datetime.datetime(*time.strptime(value, format)[:6]) except ValueError: continue return None

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• how to solve the errors of this program

  - by hussein abdullah

  include using std::cout; using std::cin; using std::endl; include void initialize(char[],int*); void input(const char[] ,int&); void print ( const char*,const int); void growOlder (const char [], int* ); bool comparePeople(const char* ,const int*,const char*,const int*); int main(){ char name1[25]; char name2[25]; int age1; int age2; initialize (name1,&age1); initialize (name2,&age2); print(name1,*age1); print(name2,*age2); input(name1,age1); input(name2,age2); print(&name1,&age1); print(&name2,&age2); growOlder(name2,age2); if(comparePeople(name1,&age1,name2,&age2)) cout<<"Both People have the same name and age "<<endl; return 0; } void input(const char name[],int &age) { cout<<"Enter a name :"; cinname ; cout<<"Enter an age:"; cin>>age; cout<<endl; } void initialize ( char name[],int *age) { name=""; age=0; } void print ( const char name[],const int age ) { cout<<"The Value stored in variable name is :" < void growOlder(const char name[],int *age) { cout<< name <<" has grown one year older\n\n"; *age++; } bool comparePeople (const char *name1,const int *age1, const char *name2,const int *age2) { return(age1==age2 &&strcmp(name1,name2)); }

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• Bound DataGridView not updating data source

  - by Max Yaffe

  I'm trying to bind a table of structures to a DataGridView. Loading and viewing the table is working fine but I can't edit a value and get it stored back into the table. Here's what I'm doing. I have a "primitive" data type, Real defined by public struct MyReal:IMyPrimative { public Double m_Real; //... public MyReal(String val) { m_Real = default(Double); Init(val); } //... } It gets used in a structure: public struct MyReal_Record : IMyRecord { public MyReal Freq { get; set;} MyReal_Record(String[] vals) { Init(vals); } } And the structure is used to define a table using a generic Binding List public class MyTable<S> : BindingList<S> where S: struct, IMyRecord { public Type typeofS; public MyTable() { typeofS = typeof(S); // ... } This table is used as a binding source for a grid, dynamically. private void miLoadFile_Click(object sender, EventArgs e) { MyModel.Table<Real_Record> RTable = new MyModel.Table<Real_Record>(); //... Table initialized here //set up grid with virtual mode dataGridView1.DataSource = RTable; } All of this works fine and I can create RTable, initialize it and display it in a grid. The grid allows editing and has events set for CellParsing and CellFormatting which look like: private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e) { if (e.DesiredType != typeof(String)) return; e.Value = e.Value.ToString(); } private void dataGridView1_CellParsing(object sender, DataGridViewCellParsingEventArgs e) { if (e.DesiredType != typeof(MyReal)) return; e.Value = new MyReal(e.Value.ToString()); e.ParsingApplied = true; this.dataGridView1.UpdateCellValue(e.ColumnIndex, e.RowIndex); } When I edit a value in a cell, I can change the text. On leaving the cell, CellParsing fires and the event handler is called. Everything seems to be correct going into the CellParsing handler. e.DesiredType is MyReal. e.Value is a string with the new value. After the new MyReal is created from the string, e.Value is set correctly. RowIndex and ColumnIndex are correct. ReadOnly is set false. However, when I leave the cell, the system restores the original value to the cell. I thought the UpdateCellValue would replace the value in the dataSource but I seem to be missing something. What did I miss? Thanks, Max

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• how i can use SAX parser

  - by moustafa

  This is what the result should look like when i parse it through a SAX parser http://img13.imageshack.us/img13/6950/75914446.jpg This is the XML source code from which i need to generate the display: <orders> <order> <count>37</count> <price>49.99</price> <book> <isbn>0130897930</isbn> <title>Core Web Programming Second Edition</title> <authors> <count>2</count> <author>Marty Hall</author> <author>Larry Brown</author> </authors> </book> </order> <order> <count>1</count> <price>9.95</price> <yacht> <manufacturer>Luxury Yachts, Inc.</manufacturer> <model>M-1</model> <standardFeatures oars="plastic" lifeVests="none">false</standardFeatures> </yacht> </order> <order> <count>3</count> <price>22.22</price> <book> <isbn>B000059Z4H</isbn> <title>Harry Potter and the Order of the Phoenix</title> <authors> <count>1</count> <author>J.K. Rowling</author> </authors> </book> </order> i really have no clue how to code the functions but i have just set up the parser $xmlParser = xml_parser_create("UTF-8"); xml_parser_set_option($xmlParser, XML_OPTION_CASE_FOLDING, false); xml_set_element_handler($xmlParser, 'startElement', 'endElement'); xml_set_character_data_handler($xmlParser, 'HandleCharacterData'); $fileName = 'orders.xml'; if (!($fp = fopen($fileName, 'r'))){ die('Cannot open the XML file: ' . $fileName); } while ($data = fread($fp, 4096)){ $parsedOkay = xml_parse($xmlParser, $data, feof($fp)); if (!$parsedOkay){ print ("There was an error or the parser was finished."); break; } } xml_parser_free($xmlParser); function startElement($xmlParser, $name, $attribs) { } function endElement($parser, $name) { } function HandleCharacterData($parser, $data) { }

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• How to apply or chain multiple matching templates in XSLT?

  - by Ignatius

  I am working on a stylesheet employing many templates with match attributes: <xsl:template match="//one" priority="0.7"> <xsl:param name="input" select="."/> <xsl:value-of select="util:uppercase($input)"/> <xsl:next-match /> </xsl:template> <xsl:template match="/stuff/one"> <xsl:param name="input" select="."/> <xsl:value-of select="util:add-period($input)"/> </xsl:template> <xsl:function name="util:uppercase"> <xsl:param name="input"/> <xsl:value-of select="upper-case($input)"/> </xsl:function> <xsl:function name="util:add-period"> <xsl:param name="input"/> <xsl:value-of select="concat($input,'.')"/> </xsl:function> What I would like to do is be able to 'chain' the two functions above, so that an input of 'string' would be rendered in the output as 'STRING.' (with the period.) I would like to do this in such a way that doesn't require knowledge of other templates in any other template. So, for instance, I would like to be able to add a "util:add-colon" method without having to open up the hood and monkey with the existing templates. I was playing around with the <xsl:next-match/> instruction to accomplish this. Adding it to the first template above does of course invoke both util:uppercase and util:add-period, but the output is an aggregation of each template output (i.e. 'STRINGstring.') It seems like there should be an elegant way to chain any number of templates together using something like <xsl:next-match/>, but have the output of each template feed the input of the next one in the chain. Am I overlooking something obvious?

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• Establishing a tcp connection from within a DLL

  - by Nicholas Hollander

  I'm trying to write a piece of code that will allow me to establish a TCP connection from within a DLL file. Here's my situation: I have a ruby application that needs to be able to send and receive data over a socket, but I can not access the native ruby socket methods because of the environment in which it will be running. I can however access a DLL file and run the functions within that, so I figured I would create a wrapper for winsock. Unfortunately, attempting to take a piece of code that should connect to a TCP socket in a normal C++ application throws a slew of LNK2019 errors that I can not for the life of me resolve. This is the method I'm using to connect: //Socket variable SOCKET s; //Establishes a connection to the server int server_connect(char* addr, int port) { //Start up Winsock WSADATA wsadata; int error = WSAStartup(0x0202, &wsadata); //Check if something happened if (error) return -1; //Verify Winock version if (wsadata.wVersion != 0x0202) { //Clean up and close WSACleanup(); return -2; } //Get the information needed to finalize a socket SOCKADDR_IN target; target.sin_family = AF_INET; //Address family internet target.sin_port = _WINSOCKAPI_::htons(port); //Port # target.sin_addr.s_addr = inet_addr(addr); //Create the socket s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (s == INVALID_SOCKET) { return -3; } //Try connecting if (connect(s, (SOCKADDR *)&target, sizeof(target)) == SOCKET_ERROR) { //Failed to connect return -4; } else { //Success return 1; } } The exact errors that I'm receiving are: Error 1 error LNK2019: unresolved external symbol _closesocket@4 referenced in function _server_disconnect [Project Path] Error 2 error LNK2019: unresolved external symbol _connect@12 referenced in function _server_connect [Project Path] Error 3 error LNK2019: unresolved external symbol _htons@4 referenced in function _server_connect [Project Path] Error 4 error LNK2019: unresolved external symbol _inet_addr@4 referenced in function _server_connect [Project Path] Error 5 error LNK2019: unresolved external symbol _socket@12 referenced in function _server_connect [Project Path] Error 6 error LNK2019: unresolved external symbol _WSAStartup@8 referenced in function _server_connect [Project Path] Error 7 error LNK2019: unresolved external symbol _WSACleanup@0 referenced in function _server_connect [Project Path] Error 8 error LNK1120: 7 unresolved externals [Project Path] 1 1 Many thanks!

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• Strange behavior of move with strings

  - by Umair Ahmed

  I am testing some enhanced string related functions with which I am trying to use move as a way to copy strings around for faster, more efficient use without delving into pointers. While testing a function for making a delimited string from a TStringList, I encountered a strange issue. The compiler referenced the bytes contained through the index when it was empty and when a string was added to it through move, index referenced the characters contained. Here is a small downsized barebone code sample:- unit UI; interface uses System.SysUtils, System.Types, System.UITypes, System.Rtti, System.Classes, System.Variants, FMX.Types, FMX.Controls, FMX.Forms, FMX.Dialogs, FMX.Layouts, FMX.Memo; type TForm1 = class(TForm) Results: TMemo; procedure FormCreate(Sender: TObject); end; var Form1: TForm1; implementation {$R *.fmx} function StringListToDelimitedString ( const AStringList: TStringList; const ADelimiter: String ): String; var Str : String; Temp1 : NativeInt; Temp2 : NativeInt; DelimiterSize : Byte; begin Result := ' '; Temp1 := 0; DelimiterSize := Length ( ADelimiter ) * 2; for Str in AStringList do Temp1 := Temp1 + Length ( Str ); SetLength ( Result, Temp1 ); Temp1 := 1; for Str in AStringList do begin Temp2 := Length ( Str ) * 2; // Here Index references bytes in Result Move ( Str [1], Result [Temp1], Temp2 ); // From here the index seems to address characters instead of bytes in Result Temp1 := Temp1 + Temp2; Move ( ADelimiter [1], Result [Temp1], DelimiterSize ); Temp1 := Temp1 + DelimiterSize; end; end; procedure TForm1.FormCreate(Sender: TObject); var StrList : TStringList; Str : String; begin // Test 1 : StringListToDelimitedString StrList := TStringList.Create; Str := ''; StrList.Add ( 'Hello1' ); StrList.Add ( 'Hello2' ); StrList.Add ( 'Hello3' ); StrList.Add ( 'Hello4' ); Str := StringListToDelimitedString ( StrList, ';' ); Results.Lines.Add ( Str ); StrList.Free; end; end. Please devise a solution and if possible, some explanation. Alternatives are welcome too.

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• USB windows xp final USB access issues

  - by Lex Dean

  I basically understand you C++ people, Please do not get distracted because I'm writing in Delphi. I have a stable USB Listing method that accesses all my USB devices I get the devicepath, and this structure: TSPDevInfoData = packed record Size: DWORD; ClassGuid: TGUID; DevInst: DWORD; // DEVINST handle Reserved: DWord; end; I get my ProductID and VenderID successfully from my DevicePath Lists all USB devices connected to the computer at the time That enables me to access the registry data to each device in a stable way. What I'm lacking is a little direction Is friendly name able to be written inside the connected USB Micro chips by the firmware programmer? (I'm thinking of this to identify the device even further, or is this to help identify Bulk data transfer devices like memory sticks and camera's) Can I use SPDRP_REMOVAL_POLICY_OVERRIDE to some how reset these polices What else can I do with the registry details. Identifying when some one unplugs a device The program is using (in windows XP standard) I used a documented windows event that did not respond. Can I read a registry value to identify if its still connected? using CreateFileA (DevicePath) to send and receive data I have read when some one unplugs in the middle of a data transfer its difficult clearing resources. what can IoCreateDevice do for me and how does one use it for that task This two way point of connection status and system lock up situations is very concerning. Has some one read anything about this subject recently? My objectives are to 1. list connected USB devices identify a in development Micro Controller from everything else send and receive data in a stable and fast way to the limits of the controller No lock up's transferring data Note I'm not using any service packs I understand everything USB is in ANSI when windows xp is not and .Net is all about ANSI (what a waste of memory) I plan to continue this project into a .net at a later date as an addition. MSDN gives me Structures and Functions and what should link to what ok but say little to what they get used for. What is available in my language Delphi is way over priced that it needs a major price drop.

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• How do I recover from an unchecked exception?

  - by erickson

  Unchecked exceptions are alright if you want to handle every failure the same way, for example by logging it and skipping to the next request, displaying a message to the user and handling the next event, etc. If this is my use case, all I have to do is catch some general exception type at a high level in my system, and handle everything the same way. But I want to recover from specific problems, and I'm not sure the best way to approach it with unchecked exceptions. Here is a concrete example. Suppose I have a web application, built using Struts2 and Hibernate. If an exception bubbles up to my "action", I log it, and display a pretty apology to the user. But one of the functions of my web application is creating new user accounts, that require a unique user name. If a user picks a name that already exists, Hibernate throws an org.hibernate.exception.ConstraintViolationException (an unchecked exception) down in the guts of my system. I'd really like to recover from this particular problem by asking the user to choose another user name, rather than giving them the same "we logged your problem but for now you're hosed" message. Here are a few points to consider: There a lot of people creating accounts simultaneously. I don't want to lock the whole user table between a "SELECT" to see if the name exists and an "INSERT" if it doesn't. In the case of relational databases, there might be some tricks to work around this, but what I'm really interested in is the general case where pre-checking for an exception won't work because of a fundamental race condition. Same thing could apply to looking for a file on the file system, etc. Given my CTO's propensity for drive-by management induced by reading technology columns in "Inc.", I need a layer of indirection around the persistence mechanism so that I can throw out Hibernate and use Kodo, or whatever, without changing anything except the lowest layer of persistence code. As a matter of fact, there are several such layers of abstraction in my system. How can I prevent them from leaking in spite of unchecked exceptions? One of the declaimed weaknesses of checked exceptions is having to "handle" them in every call on the stack—either by declaring that a calling method throws them, or by catching them and handling them. Handling them often means wrapping them in another checked exception of a type appropriate to the level of abstraction. So, for example, in checked-exception land, a file-system–based implementation of my UserRegistry might catch IOException, while a database implementation would catch SQLException, but both would throw a UserNotFoundException that hides the underlying implementation. How do I take advantage of unchecked exceptions, sparing myself of the burden of this wrapping at each layer, without leaking implementation details?

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• File sizing issue in DOS/FAT

  - by Heather

  I've been tasked with writing a data collection program for a Unitech HT630, which runs a proprietary DOS operating system that can run executables compiled for 16-bit MS DOS with some restrictions. I'm using the Digital Mars C/C++ compiler, which is working well thus far. One of the application requirements is that the data file must be human-readable plain text, meaning the file can be imported into Excel or opened by Notepad. I'm using a variable length record format much like CSV that I've successfully implemented using the C standard library file I/O functions. When saving a record, I have to calculate whether the updated record is larger or smaller than the version of the record currently in the data file. If larger, I first shift all records immediately after the current record forward by the size difference calculated before saving the updated record. EOF is extended automatically by the OS to accommodate the extra data. If smaller, I shift all records backwards by my calculated offset. This is working well, however I have found no way to modify the EOF marker or file size to ignore the data after the end of the last record. Most of the time records will grow in size because the data collection program will be filling some of the empty fields with data when saving a record. Records will only shrink in size when a correction is made on an existing entry, or on a normal record save if the descriptive data in the record is longer than what the program reads in memory. In the situation of a shrinking record, after the last record in the file I'm left with whatever data was sitting there before the shift. I have been writing an EOF delimiter into the file after a "shrinking record save" to signal where the end of my records are and space-filling the remaining data, but then I no longer have a clean file until a "growing record save" extends the size of the file over the space-filled area. The truncate() function in unistd.h does not work (I'm now thinking this is for *nix flavors only?). One proposed solution I've seen involves creating a second file and writing all the data you wish to save into that file, and then deleting the original. Since I only have 4MB worth of disk space to use, this works if the file size is less than 2MB minus the size of my program executable and configuration files, but would fail otherwise. It is very likely that when this goes into production, users would end up with a file exceeding 2MB in size. I've looked at Ralph Brown's Interrupt List and the interrupt reference in IBM PC Assembly Language and Programming and I can't seem to find anything to update the file size or similar. Is reducing a file's size without creating a second file even possible in DOS?

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• SDL Video Init causes Exception on Mac OS X 10.8

  - by ScrollerBlaster

  I have just ported my C++ game to OS X and the first time it ran I get the following exception when trying to call SDL_SetVideoMode. 2012-09-28 15:01:05.437 SCRAsteroids[28595:707] * Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Error (1000) creating CGSWindow on line 259' * First throw call stack: ( 0 CoreFoundation 0x00007fff8b53b716 __exceptionPreprocess + 198 1 libobjc.A.dylib 0x00007fff90e30470 objc_exception_throw + 43 2 CoreFoundation 0x00007fff8b53b4ec +[NSException raise:format:] + 204 3 AppKit 0x00007fff8a26a579 _NSCreateWindowWithOpaqueShape2 + 655 4 AppKit 0x00007fff8a268d70 -[NSWindow _commonAwake] + 2002 5 AppKit 0x00007fff8a2277e2 -[NSWindow _commonInitFrame:styleMask:backing:defer:] + 1763 6 AppKit 0x00007fff8a22692f -[NSWindow _initContent:styleMask:backing:defer:contentView:] + 1568 7 AppKit 0x00007fff8a2262ff -[NSWindow initWithContentRect:styleMask:backing:defer:] + 45 8 libSDL-1.2.0.dylib 0x0000000107c228f6 -[SDL_QuartzWindow initWithContentRect:styleMask:backing:defer:] + 294 9 libSDL-1.2.0.dylib 0x0000000107c20505 QZ_SetVideoMode + 2837 10 libSDL-1.2.0.dylib 0x0000000107c17af5 SDL_SetVideoMode + 917 11 SCRAsteroids 0x0000000107be60fb _ZN11SDLGraphics4initEP6IWorldii + 291 ) libc++abi.dylib: terminate called throwing an exception Abort trap: 6 My init code looks like this: if (SDL_Init(SDL_INIT_EVERYTHING) < 0) return false; const SDL_VideoInfo *videoInfo = SDL_GetVideoInfo(); if (!videoInfo) { fprintf(stderr, "Video query failed: %s\n", SDL_GetError()); return false; } /* the flags to pass to SDL_SetVideoMode */ videoFlags = SDL_OPENGL; /* Enable OpenGL in SDL */ videoFlags |= SDL_GL_DOUBLEBUFFER; /* Enable double buffering */ videoFlags |= SDL_HWPALETTE; /* Store the palette in hardware */ /* This checks to see if surfaces can be stored in memory */ if (videoInfo->hw_available) videoFlags |= SDL_HWSURFACE; else videoFlags |= SDL_SWSURFACE; if (w == 0) { widthViewport = videoInfo->current_w; heightViewport = videoInfo->current_h; cout << "Will use full screen resolution of "; videoFlags |= SDL_FULLSCREEN; } else { cout << "Will use full user supplied resolution of "; widthViewport = w; heightViewport = h; videoFlags |= SDL_RESIZABLE; /* Enable window resizing */ } cout << widthViewport << "x" << heightViewport << "\n"; /* This checks if hardware blits can be done */ if (videoInfo->blit_hw) videoFlags |= SDL_HWACCEL; /* Sets up OpenGL double buffering */ SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); /* get a SDL surface */ surface = SDL_SetVideoMode(widthViewport, heightViewport, SCREEN_BPP, videoFlags); It gets into that last SDL call and throws the exception above. I have tried it in both full screen and resizable window mode, same thing. I build my app old school, on the command line, as opposed to using Xcode.

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