Search Results

Search found 12834 results on 514 pages for 'small wolf'.

Page 471/514 | < Previous Page | 467 468 469 470 471 472 473 474 475 476 477 478  | Next Page >

  • Nested WHILE loops not acting as expected - Javascript / Google Apps Script

    - by dthor
    I've got a function that isn't acting as intended. Before I continue, I'd like preface this with the fact that I normally program in Mathematica and have been tasked with porting over a Mathematica function (that I wrote) to JavaScript so that it can be used in a Google Docs spreadsheet. I have about 3 hours of JavaScript experience... The entire (small) project is calculating the Gross Die per Wafer, given a wafer and die size (among other inputs). The part that isn't working is where I check to see if any corner of the die is outside of the effective radius, Reff. The function takes a list of X and Y coordinates which, when combined, create the individual XY coord of the center of the die. That is then put into a separate function "maxDistance" that calculates the distance of each of the 4 corners and returns the max. This max value is checked against Reff. If the max is inside the radius, 1 is added to the die count. // Take a list of X and Y values and calculate the Gross Die per Wafer function CoordsToGDW(Reff,xSize,ySize,xCoords,yCoords) { // Initialize Variables var count = 0; // Nested loops create all the x,y coords of the die centers for (var i = 0; i < xCoords.length; i++) { for (var j = 0; j < yCoords.length, j++) { // Add 1 to the die count if the distance is within the effective radius if (maxDistance(xCoords[i],yCoords[j],xSize,ySize) <= Reff) {count = count + 1} } } return count; } Here are some examples of what I'm getting: xArray={-52.25, -42.75, -33.25, -23.75, -14.25, -4.75, 4.75, 14.25, 23.75, 33.25, 42.75, 52.25, 61.75} yArray={-52.5, -45.5, -38.5, -31.5, -24.5, -17.5, -10.5, -3.5, 3.5, 10.5, 17.5, 24.5, 31.5, 38.5, 45.5, 52.5, 59.5} CoordsToGDW(45,9.5,7.0,xArray,yArray) returns: 49 (should be 72) xArray={-36, -28, -20, -12, -4, 4, 12, 20, 28, 36, 44} yArray={-39, -33, -27, -21, -15, -9, -3, 3, 9, 15, 21, 27, 33, 39, 45} CoordsToGDW(32.5,8,6,xArray,yArray) returns: 39 (should be 48) I know that maxDistance() is returning the correct values. So, where's my simple mistake? Also, please forgive me writing some things in Mathematica notation... Edit #1: A little bit of formatting. Edit #2: Per showi, I've changed WHILE loops to FOR loops and replaced <= with <. Still not the right answer. It did clean things up a bit though... Edit #3: What I'm essentially trying to do is take [a,b] and [a,b,c] and return [[a,a],[a,b],[a,c],[b,a],[b,b],[b,c]]

    Read the article

  • How to do a proper search with nhibernate

    - by Denis Rosca
    Hello everyone, i'm working on a small project that is supposed to allow basic searches of the database. Currently i'm using nhibernate for the database interaction. In the database i have 2 tables: Person and Address. The Person table has a many-to-one relationship with Address. The code i've come up with for doing searches is: public IList<T> GetByParameterList(List<QueryParameter> parameterList) { if (parameterList == null) { return GetAll(); } using (ISession session = NHibernateHelper.OpenSession()) { ICriteria criteria = session.CreateCriteria<T>(); foreach (QueryParameter param in parameterList) { switch (param.Constraint) { case ConstraintType.Less: criteria.Add(Expression.Lt(param.ParameterName, param.ParameterValue)); break; case ConstraintType.More: criteria.Add(Expression.Gt(param.ParameterName, param.ParameterValue)); break; case ConstraintType.LessOrEqual: criteria.Add(Expression.Le(param.ParameterName, param.ParameterValue)); break; case ConstraintType.EqualOrMore: criteria.Add(Expression.Ge(param.ParameterName, param.ParameterValue)); break; case ConstraintType.Equals: criteria.Add(Expression.Eq(param.ParameterName, param.ParameterValue)); break; case ConstraintType.Like: criteria.Add(Expression.Like(param.ParameterName, param.ParameterValue)); break; } } try { IList<T> result = criteria.List<T>(); return result; } catch { //TODO: Implement some exception handling throw; } } } The query parameter is a helper object that i use to create criterias and send it to the dal, it looks like this: public class QueryParameter { public QueryParameter(string ParameterName, Object ParameterValue, ConstraintType constraintType) { this.ParameterName = ParameterName; this.ParameterValue = ParameterValue; this.Constraint = constraintType; } public string ParameterName { get; set; } public Object ParameterValue { get; set; } public ConstraintType Constraint { get; set; } } Now this works well if i'm doing a search like FirstName = "John" , but not when i try to give a parameter like Street = "Some Street". It seems that nhibernate is looking for a street column in the Person table but not in the Address table. Any idea on how should i change my code for so i could do a proper search? Tips? Maybe some alternatives? Disclaimer: i'm kind of a noob so please be gentle ;) Thanks, Denis.

    Read the article

  • Web Url contains Spanish Characters which my NSXMLParser is not parsing

    - by mAc
    I am Parsing Web urls from server and storing them in Strings and then displaying it on Webview. But now when i am parsing Spanish words like http://litofinter.es.milfoil.arvixe.com/litofinter/PDF/Presentación_LITOFINTER_(ES).pdf it is accepting it PDF File Name ++++++ http://litofinter.es.milfoil.arvixe.com/litofinter/PDF/Presentaci PDF File Name ++++++ ón_LITOFINTER_(ES).pdf i.e two different strings... i know i have to make small change that is append the string but i am not able to do it now, can anyone help me out. Here is my code :- - (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict { currentElement = elementName; if([currentElement isEqualToString:@"category"]) { NSLog(@"Current element in Category:- %@",currentElement); obj = [[Litofinter alloc]init]; obj.productsArray = [[NSMutableArray alloc]init]; } if([currentElement isEqualToString:@"Product"]) { obj.oneObj = [[Products alloc]init]; } } - (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string { if([currentElement isEqualToString:@"Logo"]) { obj.cLogo=[NSString stringWithFormat:@"%@",string]; NSLog(@"Logo to be saved in Array :- %@",obj.cLogo); } if([currentElement isEqualToString:@"Name"]) { obj.cName=[NSString stringWithFormat:@"%@",string]; NSLog(@"Name to be saved in Array :- %@",string); } if([currentElement isEqualToString:@"cid"]) { obj.cId=(int)[NSString stringWithFormat:@"%@",string]; NSLog(@"CID to be saved in Array :- %@",string); } if([currentElement isEqualToString:@"pid"]) { //obj.oneObj.id = (int)[NSString stringWithFormat:@"%@",oneBook.id]; obj.oneObj.id = (int)[oneBook.id intValue]; } if([currentElement isEqualToString:@"Title"]) { obj.oneObj.title = [NSString stringWithFormat:@"%@",string]; } if([currentElement isEqualToString:@"Thumbnail"]) { obj.oneObj.thumbnail= [NSString stringWithFormat:@"%@",string]; } // problem occuriing while parsing Spanish characters... if([currentElement isEqualToString:@"pdf"]) { obj.oneObj.pdf = [NSString stringWithFormat:@"%@",string]; NSLog(@"PDF File Name ++++++ %@",string); } } - (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName { if([elementName isEqualToString:@"category"]) { NSLog(@"Current element in End Element Category:- %@",currentElement); [TableMutableArray addObject:obj]; } if([elementName isEqualToString:@"Product"]) { [obj.productsArray addObject:obj.oneObj]; } currentElement = @""; } I will be thankful to you.

    Read the article

  • How do I use Ruby metaprogramming to refactor this common code?

    - by James Wenton
    I inherited a project with a lot of badly-written Rake tasks that I need to clean up a bit. Because the Rakefiles are enormous and often prone to bizarre nonsensical dependencies, I'm simplifying and isolating things a bit by refactoring everything to classes. Specifically, that pattern is the following: namespace :foobar do desc "Frozz the foobar." task :frozzify do unless Rake.application.lookup('_frozzify') require 'tasks/foobar' Foobar.new.frozzify end Rake.application['_frozzify'].invoke end # Above pattern repeats many times. end # Several namespaces, each with tasks that follow this pattern. In tasks/foobar.rb, I have something that looks like this: class Foobar def frozzify() # The real work happens here. end # ... Other tasks also in the :foobar namespace. end For me, this is great, because it allows me to separate the task dependencies from each other and to move them to another location entirely, and I've been able to drastically simplify things and isolate the dependencies. The Rakefile doesn't hit a require until you actually try to run a task. Previously this was causing serious issues because you couldn't even list the tasks without it blowing up. My problem is that I'm repeating this idiom very frequently. Notice the following patterns: For every namespace :xyz_abc, there is a corresponding class in tasks/... in the file tasks/[namespace].rb, with a class name that looks like XyzAbc. For every task in a particular namespace, there is an identically named method in the associated namespace class. For example, if namespace :foo_bar has a task :apples, you would expect to see def apples() ... inside the FooBar class, which itself is in tasks/foo_bar.rb. Every task :t defines a "meta-task" _t (that is, the task name prefixed with an underscore) which is used to do the actual work. I still want to be able to specify a desc-description for the tasks I define, and that will be different for each task. And, of course, I have a small number of tasks that don't follow the above pattern at all, so I'll be specifying those manually in my Rakefile. I'm sure that this can be refactored in some way so that I don't have to keep repeating the same idiom over and over, but I lack the experience to see how it could be done. Can someone give me an assist?

    Read the article

  • urgent..haskell mini interpreter

    - by mohamed elshikh
    i'm asked to implement this project and i have problems in part b which is the eval function this is the full describtion of the project You are required to implement an interpreter for mini-Haskell language. An interpreter is dened in Wikipedia as a computer program that executes, i.e. performs, instructions written in a programming language. The interpreter should be able to evaluate functions written in a special notation, which you will dene. A function is dened by: Function name Input Parameters : dened as a list of variables. The body of the function. The body of the function can be any of the following statements: a) Variable: The function may return any of the input variables. b) Arithmetic Expressions: The arithmetic expressions include input variables and addition, sub- traction, multiplication, division and modulus operations on arithmetic expressions. c) Boolean Expressions: The Boolean expressions include the ordering of arithmetic expressions (applying the relationships: <, =<, , = or =) and the anding, oring and negation of Boolean expressions. d) If-then-else statements: where the if keyword is followed by a Boolean expression. The then and else parts may be followed by any of the statements described here. e) Guarded expressions: where each case consists of a boolean expression and any of the statements described here. The expression consists of any number of cases. The rst case whose condition is true, its body should be evaluated. The guarded expression has to terminate with an otherwise case. f) Function calls: the body of the function may have a call to another function. Note that all inputs passed to the function will be of type Int. The output of the function can be of type Int or Bool. To implement the interpreter, you are required to implement the following: a) Dene a datatype for the following expressions: Variables Arithmetic expressions Boolean expressions If-then-else statements Guarded expressions Functions b) Implement the function eval which evaluates a function. It takes 3 inputs: The name of a function to be evaluated represented as a string. A list of inputs to that function. The arguments will always be of datatype Int. A list of functions. Each function is represented as instance of the datatype that you have created for functions. c) Implement the function get_type that returns the type of the function (as a string). The input to this function is the same as in part b. here is what i've done data Variable = v(char) data Arth= va Variable | Add Arth Arth | Sub Arth Arth | Times Arth Arth | Divide Arth Arth data Bol= Great Arth Arth | Small Arth Arth | Geq Arth Arth | Seq Arth Arth | And Bol Bol | Or Bol Bol | Neg Bol data Cond = data Guard = data Fun =cons String [Variable] Body data Body= bodycons(String) |Bol |Cond |Guard |Arth

    Read the article

  • How to approach copying objects with smart pointers as class attributes?

    - by tomislav-maric
    From the boost library documentation I read this: Conceptually, smart pointers are seen as owning the object pointed to, and thus responsible for deletion of the object when it is no longer needed. I have a very simple problem: I want to use RAII for pointer attributes of a class that is Copyable and Assignable. The copy and assignment operations should be deep: every object should have its own copy of the actual data. Also, RTTI needs to be available for the attributes (their type may also be determined at runtime). Should I be searching for an implementation of a Copyable smart pointer (the data are small, so I don't need Copy on Write pointers), or do I delegate the copy operation to the copy constructors of my objects as shown in this answer? Which smart pointer do I choose for simple RAII of a class that is copyable and assignable? (I'm thinking that the unique_ptr with delegated copy/assignment operations to the class copy constructor and assignment operator would make a proper choice, but I am not sure) Here's a pseudocode for the problem using raw pointers, it's just a problem description, not a running C++ code: // Operation interface class ModelOperation { public: virtual void operate = (); }; // Implementation of an operation called Special class SpecialModelOperation : public ModelOperation { private: // Private attributes are present here in a real implementation. public: // Implement operation void operate () {}; }; // All operations conform to ModelOperation interface // These are possible operation names: // class MoreSpecialOperation; // class DifferentOperation; // Concrete model with different operations class MyModel { private: ModelOperation* firstOperation_; ModelOperation* secondOperation_; public: MyModel() : firstOperation_(0), secondOperation_(0) { // Forgetting about run-time type definition from input files here. firstOperation_ = new MoreSpecialOperation(); secondOperation_ = new DifferentOperation(); } void operate() { firstOperation_->operate(); secondOperation_->operate(); } ~MyModel() { delete firstOperation_; firstOperation_ = 0; delete secondOperation_; secondOperation_ = 0; } }; int main() { MyModel modelOne; // Some internal scope { // I want modelTwo to have its own set of copied, not referenced // operations, and at the same time I need RAII to work for it, // as soon as it goes out of scope. MyModel modelTwo (modelOne); } return 0; }

    Read the article

  • Using Selenium-IDE with a rich Javascript application?

    - by Darien
    Problem At my workplace, we're trying to find the best way to create automated-tests for an almost wholly javascript-driven intranet application. Right now we're stuck trying to find a good tradeoff between: Application code in reusable and nest-able GUI components. Tests which are easily created by the testing team Tests which can be recorded once and then automated Tests which do not break after small cosmetic changes to the site XPath expressions (or other possible expressions, like jQuery selectors) naively generated from Selenium-IDE are often non-repeatable and very fragile. Conversely, having the JS code generate special unique ID values for every important DOM-element on the page... well, that is its own headache, complicated by re-usable GUI components and IDs needing to be consistent when the test is re-run. What successes have other people had with this kind of thing? How do you do automated application-level testing of a rich JS interface? Limitations We are using JavascriptMVC 2.0, hopefully 3.0 soon so that we can upgrade to jQuery 1.4.x. The test-making folks are mostly trained to use Selenium IDE to directly record things. The test leads would prefer a page-unique HTML ID on each clickable element on the page... Training the testers to write or alter special expressions (such as telling them which HTML class-names are important branching points) is a no-go. We try to make re-usable javascript components, but this means very few GUI components can treat themselves (or what they contain) as unique. Some of our components already use HTML ID values in their operation. I'd like to avoid doing this anyway, but it complicates the idea of ID-based testing. It may be possible to add custom facilities (like a locator-builder or new locator method) to the Selenium-IDE installation testers use. Almost everything that goes on occurs within a single "page load" from a conventional browser perspective, even when items are saved Current thoughts I'm considering a system where a custom locator-builder (javascript code) for Selenium-IDE will talk with our application code as the tester is recording. In this way, our application becomes partially responsible for generating a mostly-flexible expression (XPath or jQuery) for any given DOM element. While this can avoid requiring more training for testers, I worry it may be over-thinking things.

    Read the article

  • CSS selectors : should I minimise my use of the class attribute in the HTML or optimise the speed

    - by Laurent Bourgault-Roy
    As I was working on a small website, I decided to use the PageSpeed extension to check if their was some improvement I could do to make the site load faster. However I was quite surprise when it told me that my use of CSS selector was "inefficient". I was always told that you should keep the usage of the class attribute in the HTML to a minimum, but if I understand correctly what PageSpeed tell me, it's much more efficient for the browser to match directly against a class name. It make sense to me, but it also mean that I need to put more CSS classes in my HTML. It also make my .css file a little harder to read. I usually tend to mark my CSS like this : #mainContent p.productDescription em.priceTag { ... } Which make it easy to read : I know this will affect the main content and that it affect something in a paragraph tag (so I wont start to put all sort of layout code in it) that describe a product and its something that need emphasis. However it seem I should rewrite it as .priceTag { ... } Which remove all context information about the style. And if I want to use differently formatted price tag (for example, one in a list on the sidebar and one in a paragraph), I need to use something like that .paragraphPriceTag { ... } .listPriceTag { ... } Which really annoy me since I seem to duplicate the semantic of the HTML in my classes. And that mean I can't put common style in an unqualified .priceTag { ... } and thus I need to replicate the style in both CSS rule, making it harder to make change. (Altough for that I could use multiple class selector, but IE6 dont support them) I believe making code harder to read for the sake of speed has never been really considered a very good practice . Except where it is critical, of course. This is why people use PHP/Ruby/C# etc. instead of C/assembly to code their site. It's easier to write and debug. So I was wondering if I should stick with few CSS classes and complex selector or if I should go the optimisation route and remove my fancy CSS selectors for the sake of speed? Does PageSpeed make over the top recommandation? On most modern computer, will it even make a difference?

    Read the article

  • No Method Error Undefined method 'save' for nil:NilClass

    - by BennyB
    I'm getting this error when i try to create a "Lecture" via my Lecture controller's create method. This used to work but i went on to work on other parts of the app & then of course i come back & something is now throwing this error when a user tries to create a Lecture in my app. I'm sure its something small i'm just overlooking (been at it a while & probably need to take a break)...but I'd appreciate if someone could let me know why this is happening...let me know if i need to post anything else...thx! The error I get NoMethodError in LecturesController#create undefined method `save' for nil:NilClass Rails.root: /Users/name/Sites/rails_projects/app_name Application Trace | Framework Trace | Full Trace app/controllers/lectures_controller.rb:13:in `create' My view to create a new Lecture views/lectures/new.html.erb <% provide(:title, 'Start a Lecture') %> <div class="container"> <div class="content-wrapper"> <h1>Create a Lecture</h1> <div class="row"> <div class="span 6 offset3"> <%= form_for(@lecture) do |f| %> <%= render 'shared/error_messages', :object => f.object %> <div class="field"> <%= f.text_field :title, :placeholder => "What will this Lecture be named?" %> <%= f.text_area :content, :placeholder => "Describe this Lecture & what will be learned..." %> </div> <%= f.submit "Create this Lecture", :class => "btn btn-large btn-primary" %> <% end %> </div> </div> </div> </div> Then my controller where its saying the error is coming from controllers/lectures_controller.rb class LecturesController < ApplicationController before_filter :signed_in_user, :only => [:create, :destroy] before_filter :correct_user, :only => :destroy def index end def new @lecture = current_user.lectures.build if signed_in? end def create if @lecture.save flash[:success] = "Lecture created!" redirect_to @lecture else @activity_items = [ ] render 'new' end end def show @lecture = Lecture.find(params[:id]) end def destroy @lecture.destroy redirect_to root_path end private def correct_user @lecture = current_user.lectures.find_by_id(params[:id]) redirect_to root_path if @lecture.nil? end

    Read the article

  • nodejs async.waterfall method

    - by user1513388
    Update 2 Complete code listing var request = require('request'); var cache = require('memory-cache'); var async = require('async'); var server = '172.16.221.190' var user = 'admin' var password ='Passw0rd' var dn ='\\VE\\Policy\\Objects' var jsonpayload = {"Username": user, "Password": password} async.waterfall([ //Get the API Key function(callback){ request.post({uri: 'http://' + server +'/sdk/authorize/', json: jsonpayload, headers: {'content_type': 'application/json'} }, function (e, r, body) { callback(null, body.APIKey); }) }, //List the credential objects function(apikey, callback){ var jsonpayload2 = {"ObjectDN": dn, "Recursive": true} request.post({uri: 'http://' + server +'/sdk/Config/enumerate?apikey=' + apikey, json: jsonpayload2, headers: {'content_type': 'application/json'} }, function (e, r, body) { var dns = []; for (var i = 0; i < body.Objects.length; i++) { dns.push({'name': body.Objects[i].Name, 'dn': body.Objects[i].DN}) } callback(null, dns, apikey); }) }, function(dns, apikey, callback){ // console.log(dns) var cb = []; for (var i = 0; i < dns.length; i++) { //Retrieve the credential var jsonpayload3 = {"CredentialPath": dns[i].dn, "Pattern": null, "Recursive": false} console.log(dns[i].dn) request.post({uri: 'http://' + server +'/sdk/credentials/retrieve?apikey=' + apikey, json: jsonpayload3, headers: {'content_type': 'application/json'} }, function (e, r, body) { // console.log(body) cb.push({'cl': body.Classname}) callback(null, cb, apikey); console.log(cb) }); } } ], function (err, result) { // console.log(result) // result now equals 'done' }); Update: I'm building a small application that needs to make multiple HTTP calls to a an external API and amalgamates the results into a single object or array. e.g. Connect to endpoint and get auth key - pass auth key to step 2 Connect to endpoint using auth key and get JSON results - create an object containing summary results and pass to step 3. Iterate over passed object summary results and call API for each item in the object to get detailed information for each summary line Create a single JSON data structure that contains the summary and detail information. The original question below outlines what I've tried so far! Original Question: Will the async.waterfall method support multiple callbacks? i.e. Iterate over an array thats passed from a previous item in the chain, then invoke multiple http requests each of which would have their own callbacks. e.g, sync.waterfall([ function(dns, key, callback){ var cb = []; for (var i = 0; i < dns.length; i++) { //Retrieve the credential var jsonpayload3 = {"Cred": dns[i].DN, "Pattern": null, "Recursive": false} console.log(dns[i].DN) request.post({uri: 'http://' + vedserver +'/api/cred/retrieve?apikey=' + key, json: jsonpayload3, headers: {'content_type': 'application/json'} }, function (e, r, body) { console.log(body) cb.push({'cl': body.Classname}) callback(null, cb, key); }); } }

    Read the article

  • add limited product to cart in android

    - by user1859172
    I have to develop one shopping cart app. Here i have to add the product only 5.otherwise have to display the message on alert dialog like 5 products only allowed. How can i develop this.please help me This is my code: ImageButton mImgAddCart = (ImageButton) findViewById(R.id.img_add); mImgAddCart.setOnClickListener(new OnClickListener() { public void onClick(View v) { // TODO Auto-generated method stub mTitle = txttitle.getText().toString(); mCost = text_cost_code.getText().toString(); mCost = mCost.replace("From ", ""); mTotal = txt_total.getText().toString(); mTotal = mTotal.replace("From ", ""); mQty = edit_qty_code.getText().toString(); if (Constants.mItem_Detail.size() <= 0) { HashMap<String, String> mTempObj = new HashMap<String, String>(); mTempObj.put(KEY_TITLE, mTitle); mTempObj.put(KEY_QTY, mQty); mTempObj.put(KEY_COST, mCost); mTempObj.put(KEY_TOTAL, mTotal); Constants.mItem_Detail.add(mTempObj); } else { for (int i = 0; i < Constants.mItem_Detail.size(); i++) { if (Constants.mItem_Detail.get(i).get(KEY_TITLE) .equals(mTitle)) { Constants.mItem_Detail.remove(i); break; } else { } } HashMap<String, String> mTempObj = new HashMap<String, String>(); mTempObj.put(KEY_TITLE, mTitle); mTempObj.put(KEY_QTY, mQty); mTempObj.put(KEY_COST, mCost); mTempObj.put(KEY_TOTAL, mTotal); Constants.mItem_Detail.add(mTempObj); } AlertDialog.Builder alertdialog = new AlertDialog.Builder( Small.this); alertdialog.setTitle(getResources() .getString(R.string.app_name)); alertdialog.setMessage("Add in ViewCart"); alertdialog.setPositiveButton("OK", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // TODO Auto-generated method stub finish(); } }); alertdialog.show(); } }); How can i set the condition for this.please give me one idea.

    Read the article

  • Between-request Garbage Collection using Passenger

    - by raphaelcm
    We're using Rails 3.0.7 and REE 1.8.7. Long-term, we will be upgrading, but at the moment it's not feasible. Following the advice of several blog posts, we've been tuning our GC, and have settings that work pretty well. But we would really like to run GC outside of the request-response cycle. I've tried patching Passenger per this post, and using the code supplied in this SO question. In both cases, GC does indeed happen between requests. However, every time the between-request GC happens, I see a bunch of this: MONGODB [INFO] Connecting... MONGODB admin['$cmd'].find({:ismaster=>1}).limit(-1) MONGODB admin['$cmd'].find({:ismaster=>1}).limit(-1) MONGODB admin['$cmd'].find({:ismaster=>1}).limit(-1) Starting the New Relic Agent. Installed New Relic Browser Monitoring middleware SQL (0.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES RefinerySetting Load (0.0ms) SELECT `refinery_settings`.* FROM `refinery_settings` WHERE `refinery_settings`.`scoping` = 'pages' AND `refinery_settings`.`name` = 'use_marketable_urls' LIMIT 1 SQL (0.0ms) BEGIN RefinerySetting Load (0.0ms) SELECT `refinery_settings`.* FROM `refinery_settings` WHERE `refinery_settings`.`id` = 1 LIMIT 1 AREL (0.0ms) UPDATE `refinery_settings` SET `value` = '--- \"false\"\n', `callback_proc_as_string` = NULL WHERE `refinery_settings`.`id` = 1 SQL (0.0ms) SHOW TABLES RefinerySetting Load (0.0ms) SELECT `refinery_settings`.* FROM `refinery_settings` SQL (0.0ms) COMMIT SQL (0.0ms) SHOW TABLES RefinerySetting Load (4.0ms) SELECT `refinery_settings`.* FROM `refinery_settings` WHERE `refinery_settings`.`scoping` IS NULL AND `refinery_settings`.`name` = 'user_image_sizes' LIMIT 1 SQL (0.0ms) BEGIN RefinerySetting Load (0.0ms) SELECT `refinery_settings`.* FROM `refinery_settings` WHERE `refinery_settings`.`id` = 17 LIMIT 1 AREL (0.0ms) UPDATE `refinery_settings` SET `value` = '--- \n:small: 120x120>\n:medium: 280x280>\n:large: 580x580>\n', `callback_proc_as_string` = NULL WHERE `refinery_settings`.`id` = 17 SQL (0.0ms) SHOW TABLES RefinerySetting Load (0.0ms) SELECT `refinery_settings`.* FROM `refinery_settings` SQL (0.0ms) COMMIT ******** Engine Extend: app/helpers/blog_posts_helper SQL (0.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES SQL (4.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES ******** Engine Extend: app/models/user SQL (0.0ms) describe `roles_users` SQL (0.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES SQL (4.0ms) describe `roles_users` SQL (0.0ms) SHOW TABLES SQL (4.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES SQL (0.0ms) SHOW TABLES (etc, etc, etc) Which is what happens when rails "loads the world" when the app starts up. Basically, GC.start is re-loading the app for some reason. Because of this, between-request GC is much slower than inline GC. Is there a way around this? I would love to have snappy, between-request GC if possible. Thanks.

    Read the article

  • ANSI C as core of a C# project? Is this possible?

    - by Nektarios
    I'm writing a NON-GUI app which I want to be cross platform between OS X and Windows. I'm looking at the following architecture, but I don't know if it will work on the windows side: (Platform specific entry point) - ANSI C main loop = ANSI C model code doing data processing / logic = (Platform specific helpers) So the core stuff I'm planning to write in regular ANSI C, because A) it should be platform independent, B) I'm extremely comfortable with C, C) It can do the job and do it well (Platform specific entry point) can be written in whatever necessary to get the job done, this is a small amount of code, doesn't matter to me. (Platform specific helpers) is the sticky thing. This is stuff like parsing XML, accessing databases, graphics toolkit stuff, whatever. Things that aren't easy in C. Things that modern languages/frameworks will give for free. On OS X this code will be written in Objective-C interfacing with Cocoa. On Windows I'm thinking my best bet is to use C# So on Windows my architecture (simplified) looks like (C# or C?) - ANSI C - C# Is this possible? Some thoughts/suggestions so far.. 1) Compile my C core as a .dll -- this is fine, but seems there's no way to call my C# helpers unless I can somehow get function pointers and pass them to my core, but that seems unlikely 2) Compile a C .exe and a C# .exe and have them talk via shared memory or some kind of IPC. I'm not entirely opposed to this but it obviously introduces a lot of complexity so it doesn't seem ideal 3) Instead of C# use C++, it gets me some nice data management stuff and nice helper code. And I can mix it pretty easily. And the work I do could probably easily port to Linux. But I really don't like C++, and I don't want this to turn in to a 3rd-party-library-fest. Not that it's a huge deal, but it's 2010.. anything for basic data management should be built in. And targetting Linux is really not a priority. Note that no "total" alternatives are OK as suggested in other similar questions on SO I've seen; java, RealBasic, mono.. this is an extremely performance intensive application doing soft realtime for game/simulation purposes, I need C & friends here to do it right (maybe you don't, but I do)

    Read the article

  • Is a many-to-many relationship with extra fields the right tool for my job?

    - by whichhand
    Previously had a go at asking a more specific version of this question, but had trouble articulating what my question was. On reflection that made me doubt if my chosen solution was correct for the problem, so this time I will explain the problem and ask if a) I am on the right track and b) if there is a way around my current brick wall. I am currently building a web interface to enable an existing database to be interrogated by (a small number of) users. Sticking with the analogy from the docs, I have models that look something like this: class Musician(models.Model): first_name = models.CharField(max_length=50) last_name = models.CharField(max_length=50) dob = models.DateField() class Album(models.Model): artist = models.ForeignKey(Musician) name = models.CharField(max_length=100) class Instrument(models.Model): artist = models.ForeignKey(Musician) name = models.CharField(max_length=100) Where I have one central table (Musician) and several tables of associated data that are related by either ForeignKey or OneToOneFields. Users interact with the database by creating filtering criteria to select a subset of Musicians based on data the data on the main or related tables. Likewise, the users can then select what piece of data is used to rank results that are presented to them. The results are then viewed initially as a 2 dimensional table with a single row per Musician with selected data fields (or aggregates) in each column. To give you some idea of scale, the database has ~5,000 Musicians with around 20 fields of related data. Up to here is fine and I have a working implementation. However, it is important that I have the ability for a given user to upload there own annotation data sets (more than one) and then filter and order on these in the same way they can with the existing data. The way I had tried to do this was to add the models: class UserDataSets(models.Model): user = models.ForeignKey(User) name = models.CharField(max_length=100) description = models.CharField(max_length=64) results = models.ManyToManyField(Musician, through='UserData') class UserData(models.Model): artist = models.ForeignKey(Musician) dataset = models.ForeignKey(UserDataSets) score = models.IntegerField() class Meta: unique_together = (("artist", "dataset"),) I have a simple upload mechanism enabling users to upload a data set file that consists of 1 to 1 relationship between a Musician and their "score". Within a given user dataset each artist will be unique, but different datasets are independent from each other and will often contain entries for the same musician. This worked fine for displaying the data, starting from a given artist I can do something like this: artist = Musician.objects.get(pk=1) dataset = UserDataSets.objects.get(pk=5) print artist.userdata_set.get(dataset=dataset.pk) However, this approach fell over when I came to implement the filtering and ordering of query set of musicians based on the data contained in a single user data set. For example, I could easily order the query set based on all of the data in the UserData table like this: artists = Musician.objects.all().order_by(userdata__score) But that does not help me order by the results of a given single user dataset. Likewise I need to be able to filter the query set based on the "scores" from different user data sets (eg find all musicians with a score 5 in dataset1 and < 2 in dataset2). Is there a way of doing this, or am I going about the whole thing wrong?

    Read the article

  • Coping with feelings of technical mediocrity

    - by Karim
    As I've progressed as a programmer, I noticed more nuance and areas I could study in depth. In part, I've come to think of myself from, at one point, a "guru" to now much less, even mediocre or inadequate. Is this normal, or is it a sign of a destructive excessive ambition? Background I started to program when I was still a kid, I had about 10 or 11 years. I really enjoy my work and never get bored from it. It's amazing how somebody could be paid for what he really likes to do and would be doing it anyway even for free. When I first started to program, I was feeling proud of what I was doing, each application I built was for me a success and after 2-3 year I had a feeling that I'm a coding guru. It was a nice feeling. ;-) But the more I was in the field and the more types of software I started to develop, I was starting to have a feeling that I'm completely wrong in thinking I'm a guru. I felt that I'm not even a mediocre developer. Each new field I start to work on is giving me this feeling. Like when I once developed a device driver for a client, I saw how much I need to learn about device drivers. When I developed a video filter for an application, I saw how much do I still need to learn about DirectShow, Color Spaces, and all the theory behind that. The worst thing was when I started to learn algorithms. It was several years ago. I knew then the basic structures and algorithms like the sorting, some types of trees, some hashtables, strings, etc. and when I really wanted to learn a group of structures I learned about 5-6 new types and saw that in fact even this small group has several hundred subtypes of structures. It's depressing how little time people have in their lives to learn all this stuff. I'm now a software developer with about 10 years of experience and I still feel that I'm not a proficient developer when I think about things that others do in the industry.

    Read the article

  • Recommended ASP.NET Shared Hosting

    - by coffeeaddict
    Ok, I have to admit I'm getting fed up with www.discountasp.net's pricing model and this annoyance has built up over the past 8 years or so. I've been with them for years and absolutely love them on the technical side, however it's getting ridiculously expensive for so little that you get. I mean here's my scenario: 1) I am running 2 SQL Server databases which costs me $10/ea per month so that's $20/month for 2 and I only get 500 mb disk space which is horrible 2) I am paying $10/mo just for the hosting itself which I only get 1 gig of disk space! I mean common! 3) I am simply running 2 small apps (Screwturn Wiki & Subtext Blog)...so I don't really care if it's up 99% or not, it's not worth paying a total of $300 just to keep these 2 apps running over discountasp.net Anyone else feel the same? Yes, I know they have great support, probably have great servers running behind this but in the end I really don't care as long as my site is up 95% or better. Yes, the hosting toolset rocks. But you know I bet you I can find a similar set somewhere else. I like how I can totally control IIS 7 at discountasp and I can control my own app pool etc. That's very powerful and essential. But anyone have any good alternatives to discountasp that gives me close to the same at a much more reasonable cost point? I mean http://www.m6.net/prices.aspx gives you 10 SQL Databases for $7 and 200 gigs disk space! I don't know about their tools or support but just looking at those numbers and some other hosts I've seen, I feel that discountasp.net is way out of line. They don't even offer any purchasing discounts such as it would be nice if my 2nd SQL Server is only $5/month not $10...stuff like this, to make it much more realistic and fair. Opinions (people who do have discountasp.net, people who have left them, or people who have another host they like)??? But geez $300 just to host a couple DBs and lightweight open source apps? Not worth the price they are charging. I'm almost at a price point that enables me to get a decent dedicated server! I really don't care about beta support. Not a big deal to me.

    Read the article

  • Problem in suspending 2 threads at the same time in MFC!

    - by kiddo
    I am learning about threading and multithreading..so i just created a small application in which i will update the progressbar and a static text using threading.I vl get two inputs from the user, start and end values for how long the loop should rotate.I have 2threads in my application. Thread1- to update the progressbar(according to the loop) the static text which will show the count(loop count). Thread2 - to update the another static text which will just diplay a name Basically if the user clicks start, the progressbar steps up and at the same time filecount and the name are displayed parallely. There's is another operation where if the user clicks pause it(thread) has to suspend until the user clicks resume. The problem is,the above will not work(will not suspend and resume) for both thread..but works for a singlw thread. Please check the code to get an idea and reply me what can done! on button click start void CThreadingEx3Dlg::OnBnClickedStart() { m_ProgressBar.SetRange(start,end); myThread1 = AfxBeginThread((AFX_THREADPROC)MyThreadFunction1,this); myThread2 = AfxBeginThread((AFX_THREADPROC)MyThreadFunction2,this); } thread1 UINT MyThreadFunction1(LPARAM lparam) { CThreadingEx3Dlg* pthis = (CThreadingEx3Dlg*)lparam; for(int intvalue =pthis->start;intvalue<=pthis->end; ++intvalue) { pthis->SendMessage(WM_MY_THREAD_MESSAGE1,intvalue); } return 0; } thread1 function LRESULT CThreadingEx3Dlg::OnThreadMessage1(WPARAM wparam,LPARAM lparam) { int nProgress= (int)wparam; m_ProgressBar.SetPos(nProgress); CString strStatus; strStatus.Format(L"Thread1:Processing item: %d", nProgress); m_Static.SetWindowText(strStatus); Sleep(100); return 0; } thread2 UINT MyThreadFunction2(LPARAM lparam) { CThreadingEx3Dlg* pthis = (CThreadingEx3Dlg*)lparam; for(int i =pthis->start;i<=pthis->end;i++) { pthis->SendMessage(WM_MY_THREAD_MESSAGE2,i); } return 0; } thread2 function LRESULT CThreadingEx3Dlg::OnThreadMessage2(WPARAM wparam,LPARAM lparam) { m_Static1.GetDlgItem(IDC_STATIC6); m_Static1.SetWindowTextW(L"Thread2 Running"); Sleep(100); m_Static1.SetWindowTextW(L""); Sleep(100); return TRUE; } void CThreadingEx3Dlg::OnBnClickedPause() { // TODO: Add your control notification handler code here if(!m_Track) { m_Track = TRUE; GetDlgItem(IDCANCEL)->SetWindowTextW(L"Resume"); myThread1->SuspendThread(); WaitForSingleObject(myThread1->m_hThread,INFINITE); myThread2->SuspendThread(); m_Static.SetWindowTextW(L"Paused.."); } else { m_Track = FALSE; GetDlgItem(IDCANCEL)->SetWindowTextW(L"Pause"); myThread1->ResumeThread(); myThread2->ResumeThread(); /*myEventHandler.SetEvent(); WaitForSingleObject(myThread1->m_hThread,INFINITE);*/ } }

    Read the article

  • How to design service that can provide interface as JAX-WS web service, or via JMS, or as local meth

    - by kevinegham
    Using a typical JEE framework, how do I develop and deploy a service that can be called as a web service (with a WSDL interface), be invoked via JMS messages, or called directly from another service in the same container? Here's some more context: Currently I am responsible for a service (let's call it Service X) with the following properties: Interface definition is a human readable document kept up-to-date manually. Accepts HTTP form-encoded requests to a single URL. Sends plain old XML responses (no schema). Uses Apache to accept requests + a proprietary application server (not servlet or EJB based) containing all logic which runs in a seperate tier. Makes heavy use of a relational database. Called both by internal applications written in a variety of languages and also by a small number of third-parties. I want to (or at least, have been told to!): Switch to a well-known (pref. open source) JEE stack such as JBoss, Glassfish, etc. Split Service X into Service A and Service B so that we can take Service B down for maintenance without affecting Service A. Note that Service B will depend on (i.e. need to make requests to) Service A. Make both services easier for third parties to integrate with by providing at least a WS-I style interface (WSDL + SOAP + XML + HTTP) and probably a JMS interface too. In future we might consider a more lightweight API too (REST + JSON? Google Protocol Buffers?) but that's a nice to have. Additional consideration are: On a smaller deployment, Service A and Service B will likely to running on the same machine and it would seem rather silly for them to use HTTP or a message bus to communicate; better if they could run in the same container and make method calls to each other. Backwards compatibility with the existing ad-hoc Service X interface is not required, and we're not planning on re-using too much of the existing code for the new services. I'm happy with either contract-first (WSDL I guess) or (annotated) code-first development. Apologies if my terminology is a bit hazy - I'm pretty experienced with Java and web programming in general, but am finding it quite hard to get up to speed with all this enterprise / SOA stuff - it seems I have a lot to learn! I'm also not very used to using a framework rather than simply writing code that calls some packages to do things. I've got as far as downloading Glassfish, knocking up a simple WSDL file and using wsimport + a little dummy code to turn that into a WAR file which I've deployed.

    Read the article

  • Keeping Velocity Constant and Player in Position - Sidescrolling

    - by user2904951
    I'm working on a Little Mobile Game with Cocos2D-X and Box2D. The Point where I got stuck is the movement of a box2d-body (the main actor) and the according Sprite. Now I want to : move this Body with a constant velocity along the x-axis, no matter if it's rolling (it's a circleshape) upwards or downwards keep the body nearly sticking to the ground on which it's rolling keep the Body and the according Sprite in the Center of the Screen. What I tried : in the update()- method I used body->SetLinearVelocity(b2Vec2(x,y)) to higher/lower values, if the Body was passing a constant value for his velocity I used to set very high y-Values in body->SetLinearVelocity(b2Vec2(x,y)) First tried to use CCFollow with my playerSprite, which was also Scrolling along the y-axis, as i only need to scroll along the x-axis, so I decided to move the whole layer which is containing the ambience (platforms etc.) to the left of my Screen and my Player Body & Player sprite to the right of the Screen, adjusting the speed values to Keep the Player in the Center of the Screen. Well... ...didn't work as i wanted it to, because each time i set the velocity manually (I also tried to use body->applyLinearImpulse(...) when the Body is moving upwards just as playing around with the value of velocityIterations in world->Step(...)) there's a small delay, which pushes the player Body more or less further of the Center of the Screen. ... didn't also work as I expected it to, because I needed to adjust the x-Values, when the Body was moving upwards to Keep it not getting slowed down, this made my Body even less sticky to the ground.... ... CCFollow did a good Job, except that I didn't want to scroll along the y-axis also and it Forces the overgiven sprite to start in the Center of the Screen. Moving the whole Layer even brought no good results, I have tried a Long time to adjust values of the movement Speed of the layer and the Body to Keep it negating each other, that the player stays nearly in the Center of the Screen.... So my question is : Does anyone of you have any Kind of new Approach for me to solve this cohesive bunch of Problems ? Cheers, Seb

    Read the article

  • How much time should it take to find the sum of all prime numbers less than 2 million?

    - by Shahensha
    I was trying to solve this Project Euler Question. I implemented the sieve of euler as a helper class in java. It works pretty well for the small numbers. But when I input 2 million as the limit it doesn't return the answer. I use Netbeans IDE. I waited for a lot many hours once, but it still didn't print the answer. When I stopped running the code, it gave the following result Java Result: 2147483647 BUILD SUCCESSFUL (total time: 2,097 minutes 43 seconds) This answer is incorrect. Even after waiting for so much time, this isn't correct. While the same code returns correct answers for smaller limits. Sieve of euler has a very simple algo given at the botton of this page. My implementation is this: package support; import java.util.ArrayList; import java.util.List; /** * * @author admin */ public class SieveOfEuler { int upperLimit; List<Integer> primeNumbers; public SieveOfEuler(int upperLimit){ this.upperLimit = upperLimit; primeNumbers = new ArrayList<Integer>(); for(int i = 2 ; i <= upperLimit ; i++) primeNumbers.add(i); generatePrimes(); } private void generatePrimes(){ int currentPrimeIndex = 0; int currentPrime = 2; while(currentPrime <= Math.sqrt(upperLimit)){ ArrayList<Integer> toBeRemoved = new ArrayList<Integer>(); for(int i = currentPrimeIndex ; i < primeNumbers.size() ; i++){ int multiplier = primeNumbers.get(i); toBeRemoved.add(currentPrime * multiplier); } for(Integer i : toBeRemoved){ primeNumbers.remove(i); } currentPrimeIndex++; currentPrime = primeNumbers.get(currentPrimeIndex); } } public List getPrimes(){ return primeNumbers; } public void displayPrimes(){ for(double i : primeNumbers) System.out.println(i); } } I am perplexed! My questions is 1) Why is it taking so much time? Is there something wrong in what I am doing? Please suggest ways for improving my coding style, if you find something wrong.

    Read the article

  • Execution plan issue requires reset on SQL Server 2005, how to determine cause?

    - by Tony Brandner
    We have a web application that delivers training to thousands of corporate students running on top of SQL Server 2005. Recently, we started seeing that a single specific query in the application went from 1 second to about 30 seconds in terms of execution time. The application started throwing timeouts in that area. Our first thought was that we may have incorrect indexes, so we reviewed the tables and indexes. However, similar queries elsewhere in the application also run quickly. Reviewing the indexes showed us that they were configured as expected. We were able to narrow it down to a single query, not a stored procedure. Running this query in SQL Studio also runs quickly. We tried running the application in a different server environment. So a different web server with the same query, parameters and database. The query still ran slow. The query is a fairly large one related to determining a student's current list of training. It includes joins and left joins on a dozen tables and subqueries. A few of the tables are fairly large (hundreds of thousands of rows) and some of the other tables are small lookup tables. The query uses a grouping clause and a few where conditions. A few of the tables are quite active and the contents change often but the volume of added rows doesn't seem extreme. These symptoms led us to consider the execution plan. First off, as soon as we reset the execution plan cache with the SQL command 'DBCC FREEPROCCACHE', the problem went away. Unfortunately, the problem started to reoccur within a few days. The problem has continued to plague us for awhile now. It's usually the same query, but we did appear to see the problem occur in another single query recently. It happens enough to be a nuisance. We're having a heck of a time trying to fix it since we can't reproduce it in any other environment other than production. I have downloaded the High Availability guide from Red Gate and I read up more on execution plans. I hope to run the profiler on the live server, but I'm a bit concerned about impact. I would like to ask - what is the best way to figure out what is triggering this problem? Has anyone else seen this same issue?

    Read the article

  • Layout issue regarding a JQuery smoothDivScroll

    - by MichaelMcCabe
    Hi all. I have been scratching my head for a while on this one. I dont really play around with HTML formatting that often. I have a smoothDivScroll using JQuery (http://maaki.com/thomas/SmoothDivScroll/) to scroll through dynamically generated images. What I want it for, is to have multiple small images lined up right next to each other, and each image has a section of writting underneath. about 25 images, 140px width each in a 7560px span. I acheived this great by putting a table inside the div, and each image inside a<td>.This works problem i have, is that i need the slider to start from the furthest RIGHT image, and slide automatically left. This is acheived by (if you look at the link above) - startAtElementId: But if I am using a table inside the div, it is taking the TABLE as a element and not the TD... so it doesnt work. I know this because if I change every image to be inside tables (i.e 25 tables), it works... but obviously then the formatting is not how I want. Can anyone think of a way I can use this slider (modifications to the js code or not), with 25 images that NEED to be right next to each other, no gap. I guess this is more of a formatting question, than about the slider. Because I only know ONE way of doing what I want, and thats to have below which will not alow me to set startAtElementId. <div class="scrollableArea"> <table width="7560px" class="index-body"> <tr> <td width="140px"><center><a onclick="__doPostBack('getEarlierDate');" ><img src="../images/olderGraphs.gif" width="140" height="60"></a>Click for more</center></td> <td width="300px"><center><a onclick="__doPostBack('chartClicked25');" ><cewolf:img chartid="verticalbar25" renderer="cewolf" width="300" height="60"/></a><c:out value="${date25}"/></center></td> <td width="300px"><center><a onclick="__doPostBack('chartClicked24');" ><cewolf:img chartid="verticalbar24" renderer="cewolf" width="300" height="60"/></a><c:out value="${date24}"/></center></td> and so on

    Read the article

  • Counting point size based on chart area during zooming/unzoomin

    - by Gacek
    Hi folks. I heave a quite simple task. I know (I suppose) it should be easy, but from the reasons I cannot understand, I try to solve it since 2 days and I don't know where I'm making the mistake. So, the problem is as follows: - we have a chart with some points - The chart starts with some known area and points have known size - we would like to "emulate" the zooming effect. So when we zoom to some part of the chart, the size of points is getting proportionally bigger. In other words, the smaller part of the chart we select, the bigger the point should get. So, we have something like that. We know this two parameters: initialArea; // Initial area - area of the whole chart, counted as width*height initialSize; // initial size of the points Now lets assume we are handling some kind of OnZoom event. We selected some part of the chart and would like to count the current size of the points float CountSizeOnZoom() { float currentArea = CountArea(...); // the area is counted for us. float currentSize = initialSize * initialArea / currentArea; return currentSize; } And it works. But the rate of change is too fast. In other words, the points are getting really big too soon. So I would like the currentSize to be invertly proportional to currentArea, but with some scaling coefficient. So I created the second function: float CountSizeOnZoom() { float currentArea = CountArea(...); % the area is counted for us. // Lets assume we want the size of points to change ten times slower, than area of the chart changed. float currentSize = initialSize + 0.1f* initialSize * ((initialArea / currentArea) -1); return currentSize; } Lets do some calculations in mind. if currentArea is smaller than initialArea, initialArea/currentArea > 1 and then we add "something" small and postive to initialSize. Checked, it works. Lets check what happens if we would un-zoom. currentArea will be equal to initialArea, so we would have 0 at the right side (1-1), so new size should be equal to initialSize. Right? Yeah. So lets check it... and it doesn't work. My question is: where is the mistake? Or maybe you have any ideas how to count this scaled size depending on current area in some other way?

    Read the article

  • Akka framework support for finding duplicate messages

    - by scala_is_awesome
    I'm trying to build a high-performance distributed system with Akka and Scala. If a message requesting an expensive (and side-effect-free) computation arrives, and the exact same computation has already been requested before, I want to avoid computing the result again. If the computation requested previously has already completed and the result is available, I can cache it and re-use it. However, the time window in which duplicate computation can be requested may be arbitrarily small. e.g. I could get a thousand or a million messages requesting the same expensive computation at the same instant for all practical purposes. There is a commercial product called Gigaspaces that supposedly handles this situation. However there seems to be no framework support for dealing with duplicate work requests in Akka at the moment. Given that the Akka framework already has access to all the messages being routed through the framework, it seems that a framework solution could make a lot of sense here. Here is what I am proposing for the Akka framework to do: 1. Create a trait to indicate a type of messages (say, "ExpensiveComputation" or something similar) that are to be subject to the following caching approach. 2. Smartly (hashing etc.) identify identical messages received by (the same or different) actors within a user-configurable time window. Other options: select a maximum buffer size of memory to be used for this purpose, subject to (say LRU) replacement etc. Akka can also choose to cache only the results of messages that were expensive to process; the messages that took very little time to process can be re-processed again if needed; no need to waste precious buffer space caching them and their results. 3. When identical messages (received within that time window, possibly "at the same time instant") are identified, avoid unnecessary duplicate computations. The framework would do this automatically, and essentially, the duplicate messages would never get received by a new actor for processing; they would silently vanish and the result from processing it once (whether that computation was already done in the past, or ongoing right then) would get sent to all appropriate recipients (immediately if already available, and upon completion of the computation if not). Note that messages should be considered identical even if the "reply" fields are different, as long as the semantics/computations they represent are identical in every other respect. Also note that the computation should be purely functional, i.e. free from side-effects, for the caching optimization suggested to work and not change the program semantics at all. If what I am suggesting is not compatible with the Akka way of doing things, and/or if you see some strong reasons why this is a very bad idea, please let me know. Thanks, Is Awesome, Scala

    Read the article

  • SwingWorker exceptions lost even when using wrapper classes

    - by Ti Strga
    I've been struggling with the usability problem of SwingWorker eating any exceptions thrown in the background task, for example, described on this SO thread. That thread gives a nice description of the problem, but doesn't discuss recovering the original exception. The applet I've been handed needs to propagate the exception upwards. But I haven't been able to even catch it. I'm using the SimpleSwingWorker wrapper class from this blog entry specifically to try and address this issue. It's a fairly small class but I'll repost it at the end here just for reference. The calling code looks broadly like try { // lots of code here to prepare data, finishing with SpecialDataHelper helper = new SpecialDataHelper(...stuff...); helper.execute(); } catch (Throwable e) { // used "Throwable" here in desperation to try and get // anything at all to match, including unchecked exceptions // // no luck, this code is never ever used :-( } The wrappers: class SpecialDataHelper extends SimpleSwingWorker { public SpecialDataHelper (SpecialData sd) { this.stuff = etc etc etc; } public Void doInBackground() throws Exception { OurCodeThatThrowsACheckedException(this.stuff); return null; } protected void done() { // called only when successful // never reached if there's an error } } The feature of SimpleSwingWorker is that the actual SwingWorker's done()/get() methods are automatically called. This, in theory, rethrows any exceptions that happened in the background. In practice, nothing is ever caught, and I don't even know why. The SimpleSwingWorker class, for reference, and with nothing elided for brevity: import java.util.concurrent.ExecutionException; import javax.swing.SwingWorker; /** * A drop-in replacement for SwingWorker<Void,Void> but will not silently * swallow exceptions during background execution. * * Taken from http://jonathangiles.net/blog/?p=341 with thanks. */ public abstract class SimpleSwingWorker { private final SwingWorker<Void,Void> worker = new SwingWorker<Void,Void>() { @Override protected Void doInBackground() throws Exception { SimpleSwingWorker.this.doInBackground(); return null; } @Override protected void done() { // Exceptions are lost unless get() is called on the // originating thread. We do so here. try { get(); } catch (final InterruptedException ex) { throw new RuntimeException(ex); } catch (final ExecutionException ex) { throw new RuntimeException(ex.getCause()); } SimpleSwingWorker.this.done(); } }; public SimpleSwingWorker() {} protected abstract Void doInBackground() throws Exception; protected abstract void done(); public void execute() { worker.execute(); } }

    Read the article

< Previous Page | 467 468 469 470 471 472 473 474 475 476 477 478  | Next Page >