Search Results

Search found 11197 results on 448 pages for 'related'.

Page 249/448 | < Previous Page | 245 246 247 248 249 250 251 252 253 254 255 256  | Next Page >

• Are C++ meta-templates required knowledge for programmers?

  - by Robert Gould

  In my experience Meta-templates are really fun (when your compilers are compliant), and can give good performance boosts, and luckily I'm surrounded by seasoned C++ programmers that also grok meta-templates, however occasionally a new developer arrives and can't make heads or tails of some of the meta-template tricks we use (mostly Andrei Alenxandrescu stuff), for a few weeks until he gets initiated appropriately. So I was wondering what's the situation for other C++ programmers out there? Should meta-template programming be something C++ programmers should be "required" to know (excluding entry level students of course), or not? Edit: Note my question is related to production code and not little samples or prototypes

  Read the article

• Stop propagating deletes

  - by Mark

  Is it just me or is anyone else finding EF very difficult to use in a real app :( I'm using it as the data layer and have created custom business objects. I'm having difficulty converting the business objects back to EF objects and updating/adding/deleting from the database. Does anyone know a good, simple example of doing this? Actually the current problem that's driving me nuts is when I delete something EF tries to delete other related stuff as well. For example, if I delete an invoice it will also delete the associated customer! Seems odd. I can't figure out how to stop it doing this. // tried: invoiceEfData.CustomerReference = null; // also tried invoiceEfData.Customer = null; context.DeleteObject(invoiceEfData); context.SaveChanges(); // at this point I get a database error due to it attempting to delete the customer

  Read the article

• How Can I up my Street Cred in the coding world

  - by RedEye

  I know this isn't directly related to a specific coding problem. It's a more general programming question. I'm a n00b... Been coding for 1 year, and it's where I belong. I want to get hardcore and put everything I have into it. I started with C++ and now I'm into C#. I love it all. What can I do to up my game and up my respect in the programming world?

  Read the article

• A simple explanation of Naive Bayes Classification

  - by Jaggerjack

  I am finding it hard to understand the process of Naive Bayes, and I was wondering if someone could explained it with a simple step by step process in English. I understand it takes comparisons by times occurred as a probability, but I have no idea how the training data is related to the actual dataset. Please give me an explanation of what role the training set plays. I am giving a very simple example for fruits here, like banana for example training set--- round-red round-orange oblong-yellow round-red dataset---- round-red round-orange round-red round-orange oblong-yellow round-red round-orange oblong-yellow oblong-yellow round-red

  Read the article

• Using clojure.contrib functions in slime REPL

  - by Tyler

  I want to use the functions in the clojure.contrib.trace namespace in slime at the REPL. How can I get slime to load them automatically? A related question, how can I add a specific namespace into a running repl? On the clojure.contrib API it describes usage like this: (ns my-namespace (:require clojure.contrib.trace)) But adding this to my code results in the file being unable to load with an "Unable to resolve symbol" error for any function from the trace package. I use leiningen 'lein swank' to start the ServerSocket and the project.clj file looks like this (defproject test-project "0.1.0" :description "Connect 4 Agent written in Clojure" :dependencies [[org.clojure/clojure "1.2.0-master-SNAPSHOT"] [org.clojure/clojure-contrib "1.2.0-SNAPSHOT"]] :dev-dependencies [[leiningen/lein-swank "1.2.0-SNAPSHOT"] [swank-clojure "1.2.0"]]) Everything seems up to date, i.e. 'lein deps' doesn't produce any changes. So what's up?

  Read the article

• In Google App Engine, what is the simplest way to keep a record of items that you have put into memc

  - by Chris Boesch

  I am starting to use memcache more frequently to avoid having to recalculate things between page requests. When the memcache periodically clears, as it is designed to do, I have to start all over rebuilding various items that I have placed in memcache. What I would like to do is create a very simple model that enables me to periodically save the items that I put into memcache based on the memcache keys that I'm using along with a datetime that is related to the data being memcached. What is the best way to do this? I'm looking for something like this: class MemcacheRecord(db.Model): key = db.StringProperty(required=True) value = #Something that can store whatever memcache can validThru = db.DateTimeProperty(required=True) def set(self, key, value, validThru): #Save a new memcache record newMemcacheRecord = MemcacheRecord(key=key, value=value, validThru=validThru) .. return True # or False def get_latest(self, key): #Get the memcache record with the most recent validThru datetime latestMemcacheRecord = MemcacheRecord.all().order('-validThru').get() return {'validThru':latestMemcacheRecord.validThru, 'value':latestMemcachRecord.value}

  Read the article

• Pattern for managing reference count and object life

  - by Gopalakrishnan Subramani

  We have a serial port which is connected to hundreds of physical devices on the same wire. We have protocols like Modbus and Hart to handle the request and response between the application and devices. The question is related to managing the reference count of the channel. When no device is using the channel, the channel should be closed. public class SerialPortChannel { int refCount = 0; public void AddReference() { refCount++; } public void ReleaseReference() { refCount--; if (refCount <= 0) this.ReleasePort(); //This close the serial port } } For each device connected, we create a object for the device like device = new Device(); device.Attach(channel); //this calls channel.AddReference() When the device disconnect, device.Detach(channel); //this calls channel.ReleaseReference() I am not convinced by the reference count model. Are there any better way to handle this problem in .NET World?

  Read the article

• JavaScript multithreading

  - by Krzysztof Hasinski

  I'm working on comparison for several different methods of implementing (real or fake) multithreading in JavaScript. As far as I know only webworkers and Google Gears WorkerPool can give you real threads (ie. spread across multiple processors with real parallel execution). I've found the following methods: switch between tasks using yield() use setInterval() (or other non-blocking function) with threads waiting one for another use Google Gears WorkerPool threads (with plugin) use html5 web workers I read related questions and found several variations of the above methods, but most of those questions are old, so there might be a few new ideas. I'm wondering - how else can you achieve multithreading in JavaScript? Any other important methods? UPDATE: As pointed out in comments what I really meant was concurrency. UPDATE 2: I found information that Silverlight + JScript supports multithreading, but I'm unable to verify this. UPDATE 3: Google deprecated Gears: http://code.google.com/apis/gears/api_workerpool.html

  Read the article

• When to release the model(representedObject) of the corresponding UIViewController.

  - by user313786

  Hi, In AppKit we have "representedObject" available through NSViewController, this representedObject is generally set to ModelController or the model which the NSViewController displays, this works great with bindings as you just set the new representedObject and model details are updated in the view, BUT in case of iPhone (UIKit, with NO Cocoa bindings available), there is no such representedObject in UIViewController so here are few things I am interested in knowing:- What is the best/recommended way of binding the model to the UIViewController?, preferably dont want to maintain lot of IBOutlets and calls setters to updated the changed model data for display in view. How/When should the related model of the UIViewController be released? When is the -[UIViewController dealloc] called, in the typical iPhone application. Am looking for architecting some classes so that the UIViewController coordinates between the view and the model, but at the same time, deallocs the model when ever not necessary. TIA.

  Read the article

• How do chains work in Rainbow tables?

  - by James Moore

  Hello, I was wondering if should one could explain in detail how chains work in rainbow tables as though you would a complete novice but with relevance to programming. I understand that a chain is 16 bytes long. 8 bytes mark the starting point and 8 mark the end. I also understand that in the filename we have the chain length i.e. 2400. Which means that between our starting point and end point in just 16 bytes we have 2400 possible clear texts? What? How does that work? in those 16 bytes how do i get my 2400 hashes and clear texts or am i miss understanding this? Your help is greatly appreciated. Thanks P.s. I have read the related papers and googled this topic a fair bit. I think im just missing something important to make these gears turn.

  Read the article

• Change an access Primary key with relationships

  - by DiegoMaK

  I have a database in access 2007 accdb extension , there are more or less 30-40 tables with related primary key "local_number". it is a text primary key with 10 lenght. How can I change the length of this primary key to 30 WITHOUT delete previosly all the 30 relationship. 2,A similar question. I need add a compose primary key to my PK "local_number". I need Add a "Date" as composed PK. Then access just allow this if I first delete all relationships. How can Avoid this warning and change my PK ignoring this message.

  Read the article

• Need Help on entity framework

  - by Sarathi1904

  I have 3 tables(Roles,Actions and RoleActionLinks). Roles table has few columns(RoleID,RoleName,Desc). Actions table has few colums(ActionID,ActionName,Desc). In RoleActionLink is created for store the association between Roles and Actions and this table has the columns such as RoleID,ActionID When I created the data model(edmx). it shows only Role and Action as entity. i did not find RoleActionLink table. but even there is no direct relation between Roles and Actions table, both tables are automatically related using RoleActionLink table. When i create the new Action, a action record should be populated in Action table(this is works fine). At the same time, i need to populate record in RoleActionLinks table. But i dont have the entity to populate. Please tell me how to accomplish my needs.

  Read the article

• Getting help on MATLAB's com.mathworks internals

  - by Richie Cotton

  It is possible to access bits of MATLAB's internal java code to programmatically change MATLAB itself. For example, you can programmatically open a document in the editor using editorServices = com.mathworks.mlservices.MLEditorServices; editorServices.newDocument() %older versions of MATLAB seem to use new() You can see the method signatures (but not what they do) using viewmethods. viewmethods(com.mathworks.mlservices.MLEditorServices) I have a few related questions about using these Java methods. Firstly, is there any documentation on these things (either from the Mathworks or otherwise)? Secondly, how do you find out what methods are available? The ones I've come across appear to be contained in JAR files in matlabroot\java\jar, but I'm not sure what the best way to inspect a JAR file is. Thirdly, are there functions for inspecting the classes, other than viewmethods? Finally, are there any really useful methods that anyone has found?

  Read the article

• SQL bottleneck, how to fix

  - by masfenix

  This is related to my previous thread: http://stackoverflow.com/questions/3069806/sql-query-takes-about-10-20-minutes However, I kinda figured out the problem. The problem (as described in the previous thread) is not the insert (while its still slow), the problem is looping through the data itself Consider the following code: Dim rs As DAO.Recordset Dim sngStart As Single, sngEnd As Single Dim sngElapsed As Single Set rs = CurrentDb().QueryDefs("select-all").OpenRecordset MsgBox "All records retreived" sngStart = Timer Do While Not rs.EOF rs.MoveNext Loop sngEnd = Timer sngElapsed = Format(sngEnd - sngStart, "Fixed") ' Elapsed time. MsgBox ("The query took " & sngElapsed _ & " seconds to run.") As you can see, this loop does NOTHING. You'd expect it to finish in seconds, however it takes about 857 seconds to run (or 15 minutes). I dont know why it is so slow. Maybe the lotusnotes sql driver? any other ideas? (java based solution, any other solution) What my goal is: To get all the data from remote server and insert into local access table

  Read the article

• How to change the cursor type

  - by Jessy

  This question is related to the previous post. http://stackoverflow.com/questions/2532936/how-to-save-file-and-read How can I change the cursor to "Hand" only when the mouse pointed on grid which is not Null (contained images)? So far the cursor turn to "Hand" all over the grids (null or not null). public GUI() { .... JPanel pDraw = new JPanel(); .... for(Component component: pDraw.getComponents()){ JLabel lbl = (JLabel)component; //add mouse listener to grid box which contained image if (lbl.getIcon() != null) lbl.addMouseListener(this); } public void mouseEntered(MouseEvent e) { Cursor cursor = Cursor.getDefaultCursor(); //change cursor appearance to HAND_CURSOR when the mouse pointed on images cursor = Cursor.getPredefinedCursor(Cursor.HAND_CURSOR); setCursor(cursor); }

  Read the article

• Propertygrid changes not picked up when using menu shortcut for saving

  - by Ebbe

  I am trying to implement a simple windows forms application, where the user can edit instances of a simple Person class. The application makes use of the standard propertygrid, assigning instances of the Person class to the SelectedObject property of the propertygrid. When the user clicks the menu item Save, the application gets the selected item from the propertygrid and saves it. This works fine. However, if a shortcut such as ctrl+S, assigned to the menu item, is used for saving the SelectedObject of the propertygrid, then the changes are not picked up. It appears to be related to the fact that the properties of the Person object are not updated unless the field in the propertygrid looses focus, and the ctrl+S shortcut doesn’t take away focus from fields in the propertygrid. Other developers, such as Mark Gilbert, have solved this issue by forcing away focus from the propertygrid, but this seems to be a bit of a hack, especially since it would be nice to keep the focus at the field. The Visual Studio developers apparently got it right, but I haven’t figured out how.

  Read the article

• Kubunutu/Windows 7 dual-boot and git

  - by Andu

  I've been using Kubuntu and Windows 7 on my laptop for some time. Recently I also started using git to keep track of a project I'm working on. At first I thought I'd use the same git repo for editing from both Kubuntu and Win, but I soon discovered that committing changes on Win would make git on Kubuntu think all the files have changed since the last commit, although the change doesn't seem to be content related. The exactly same thing happens if I do a commit on Kubuntu and right after that do a git status on Win. I know I could use different repos for Kubuntu and Win and just merge them together when I'm done, but if anyone knows how I could use the same repo I would really appreciate the help.

  Read the article

• How to run unittest under pydev for Django?

  - by photon

  I configured properties for my django project under pydev. I can run the django app under pydev or under console window. I can also run unittest for app under console window. But I have problems to run unittest under pydev. I guess it's something related to run configurations of pydev, so I made several trials, but with no success. Once I got messages like this: ImportError: Could not import settings 'D:\django_projects\MyProject' (Is it on sys.path? Does it have syntax errors?): No module named D:\django_projects\MyProject ERROR: Module: MyUnittestFile could not be imported. Another time I got messages like this: ImportError: Could not import settings 'MyProject.settngs' (Is it on sys.path? Does it have syntax errors?): No module named settngs 'ERROR: Module: MyUnittestFile could not be imported. I use pydev 1.5.6 on eclipse and windows xp. Any ideas for this problem?

  Read the article

• C++ Project compiles as static lib, fails (linker error) as dynamic lib. why??

  - by Roey

  Hi All. I've a VS2008 native C++ project, that I wish to compile as a DLL. It only references one external library (log4cplus.lib), and uses its functions. (also uses log4cplus's .h files , naturally). When I try to compile my project as a static library, it succeeeds. When I try as DLL, it fails : 1>MessageWriter.obj : error LNK2019: unresolved external symbol "public: static class log4cplus::Logger __cdecl log4cplus::Logger::getInstance(class std::basic_string<wchar_t,struct std::char_traits<wchar_t>,class std::allocator<wchar_t> > const &)" (?getInstance@Logger@log4cplus@@SA?AV12@ABV?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@Z) referenced in function "class log4cplus::Logger __cdecl Log(void)" (?Log@@YA?AVLogger@log4cplus@@XZ) There are 4 more errors just like this related to functions within log4cplus.lib. It seems like something really stupid.. please help me :) Thanks!

  Read the article

• Will pool the connection help threading in sqlite (and how)?

  - by mamcx

  I currently use a singleton to acces my database (see related question) but now when try to add some background processing everything fall apart. I read the sqlite docs and found that sqlite could work thread-safe, but each thread must have their own db connection. I try using egodatabase that promise a sqlite wrapper with thread safety but is very buggy, so I return to my old FMDB library I start to see how use it in multi-thread way. Because I have all code with the idea of singleton, change everything will be expensive (and a lot of open/close connections could become slow), so I wonder if, as the sqlite docs hint, build a pooling for each connection will help. If is the case, how make it? How know wich connection get from the pool (because 2 threads can't share the connection)? I wonder if somebody already use sqlite in multu-threading with NSOperation or similar stuff, my searching only return "yeah, its possible" but let the details to my imagination...

  Read the article

• IPhone Dev: Activate the view of a tabBar button

  - by Alex N Sanchez

  Hi, I have an application that has a tabBar that handles all the views. In the first view I have a login process. When that process finishes I want to go automatically to the second tabBar view without making the user to click in its respective tabBar button. All I've got until now is to highlight the button with this: myTabBar.selectedItem = [myTabBar.items objectAtIndex:1]; But I have no idea about how to bring the second view related to that button to the front, automatically. Until now the user has to press the button when it gets lighted (selected). Any idea about how to do this? Is it possible? It would be much appreciated. Thanks.

  Read the article

• How do I compute the approximate entropy of a bit string?

  - by dreeves

  Is there a standard way to do this? Googling -- "approximate entropy" bits -- uncovers multiple academic papers but I'd like to just find a chunk of pseudocode defining the approximate entropy for a given bit string of arbitrary length. (In case this is easier said than done and it depends on the application, my application involves 16,320 bits of encrypted data (cyphertext). But encrypted as a puzzle and not meant to be impossible to crack. I thought I'd first check the entropy but couldn't easily find a good definition of such. So it seemed like a question that ought to be on StackOverflow! Ideas for where to begin with de-cyphering 16k random-seeming bits are also welcome...) See also this related question: http://stackoverflow.com/questions/510412/what-is-the-computer-science-definition-of-entropy

  Read the article

• What process does professional website building follow?

  - by Sivvy

  I've searched for a while, but I can't find anything related on Google or here. Me and some friends were debating starting a company, so I figure it might be good to do a quick pilot project to see how well we can work together. We have a designer who can do HTML, CSS and Flash, enjoys doing art, but doesn't like to do HTML and CSS... And 2 programmers that are willing to do anything. My question is, from an experienced site builder's perspective, what steps do we do - in chronological order - to properly handle a website? Does the designer design the look and feel of the site, then the programmers fill in the gaps with functionality? Or do the programmers create a "mock-up" of the site with most of the functionality, then the designer spices it up? Or is it more of a back-and-forth process? I just want to know how a professional normally handles it.

  Read the article

• Ipad, closed environment and threat to privacy

  - by Akshay Bhat

  I had an unusual question about ipad, Since ipad environment is closed and does not allows installation of diagnostic and security related programs. How can then we be sure that any of the software installed on ipad is not infringing upon our privacy by doing stuff such as homing back information, etc. We cant install a packet tracer or any other software to check for attacks on privacy. Also given Apples poor track record (the safari browser was broken in one day), I don't think trusting apple solely would be a good idea. This might not seem to be a big issue but for business users it would be a significant concern.

  Read the article

• Correlation between JEE / J2EE to J2SE / JDK versions

  - by Ehrann Mehdan

  I was certain that I'll find a duplicate question or a satisfiyng answer, but I haven't. What I'm looking for is the answer to these questions: Is there an official correlation between JEE / J2EE and J2SE / JDK versions? If the answer is yes, where is it written? If the answer is no, then why? and is there an unofficial version table (e.g. JDK 1.4 goes well with J2EE 1.3, JDK 1.5 goes well with J2EE 1.4, JDK 1.6 with JEE 5 and so on) I can think of a couple of reasons for the uncoupling, but can't seem to find a good reference source Related questions: http://stackoverflow.com/questions/196265/jse-vs-j2ee-college-and-career/196439#196439 http://stackoverflow.com/questions/106820/what-is-j2ee-jee

  Read the article

< Previous Page | 245 246 247 248 249 250 251 252 253 254 255 256  | Next Page >