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• Different Scala Actor Implementations Overview

  - by Stefan K.

  I'm trying to find the 'right' actor implementation for my thesis. I realized there is a bunch of them and it's a bit confusing to pick one. Personally I'm especially interested in remote actors, but I guess a complete overview would be helpful to many others. This is a pretty general question, so feel free to answer just for the implementation you know about. I know about the following Scala Actor implementations (SAI). Please add the missing ones. Scala 2.7 (difference to) Scala 2.8 Akka (http://www.akkasource.org/) Lift (http://liftweb.net/) Scalaz (http://code.google.com/p/scalaz/) What are the target use-cases for these SAIs (lightweight vs. "heavy" enterprise framework)? do they support remote actors? What shortcomings do remote actors have in the SAIs? How is their performace? How active is there community? How easy are they to get started? How good is the documentation? How easy are they to extend? How stable are they? Which projects are using them? What are their shortcomings? What are their design principles? Are they thread based or event based (receive/ react) or both? Nested receiveS hotswapping the Actor’s message loop

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• Is there a Scheduler/Calendar JS Widget library?

  - by Ravi Chhabra

  I am looking for some JavaScript based component to be used as a course scheduler which would be a cross between Google Calendar and the login time. I do not know if the right term for this is Course Scheduler but I shall describe this in more detail here. Course Scheduler The widget would be used to enter date and times of a course, as an example if I run a programming course 3 days a week on Mon, Tue and Wed every 7:00 am to 9:00am, 2 hours every day from 1st September to 30th November. I could answer various questions and the course data would be displayed in the calendar. It would also allow for non pattern based timings where each week is different from the other week etc. Question So would I end up creating something from scratch? Would it be sensible to use Google Calendar API for this? I did a Google search for some widgets, but I believe I need better keywords, as I could not find anything close to what I am looking for. Any tips? Commercial libraries would also work for me. Thanks.

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• Cab't run a web application with GWText

  - by Anto

  I am using the GWT and the GWTExt libraries with Eclipse for the first time. I have followed all the procedures but when I go run the web application the following error appears: 1) In the Problems tab, I have this message: Description Resource Path Location Type The following classpath entry 'C:\Documents and Settings\CiuffreA\Desktop\GWTExt\gwtext-2.0.5\gwtext.jar' will not be available on the server's classpath GWTProject Unknown Google Web App Problem 2) In the Development Mode tab, the following 2 messages appears: 23:41:25.906 [ERROR] [mockupproject] Unable to load module entry point class com.example.myproject.client.MockUpProject Failed to load module 'mockupproject' from user agent 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US) AppleWebKit/532.5 (KHTML, like Gecko) Chrome/4.1.249.1042 Safari/532.5' at localhost:3853 If anyone has a clue about where the problem may be, please give me a hint...

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• PHP File Serving Script: Unreliable Downloads?

  - by JGB146

  This post started as a question on ServerFault ( http://serverfault.com/questions/131156/user-receiving-partial-downloads ) but I determined that our php script was the culprit. So I'm issuing an updated question here about what I believe is the actual issue. I am using a php script to verify permissions and then serve up a file for users of my website to download. Most of the time, this works, but recently one user has been seeing problems with larger downloads. He is only getting ~80% of downloads for files that are 100MB in size. Also, all downloads from this script fail to report a filesize. Further, tests revealed that the same user COULD reliably download each of the failed files if given a direct link (at which point the filesize is reported). Here's the relevant snippet of code that we are using to serve the file: header("Content-type:$contenttype"); $len = filesize($filename); header("Content-Length: $len"); header("Content-Disposition: attachment; filename=".$title.".".$ext); readfile($filename); Note that $contenttype, $filename, $title, and $ext are all set correctly before we get here. These have been triple-checked. None of them are the problem. Also, $len does provide the correct filesize. While researching this issue, I came across this post: http://stackoverflow.com/questions/1334471/content-length-header-always-zero It seems that I am encountering the same issue. When I use the script, I get chunked encoding on the file and no size is set for content-length. I'm hypothesizing that something is going wrong on the large downloads, leading him to get a zero-length chunk before the end of the file. Here's what the headers look like for a direct request: http://www.grinderschool.com/videos/zfff5061b65ae00e8b21/KillsAids021.wmv GET /videos/zfff5061b65ae00e8b21/KillsAids021.wmv HTTP/1.1 Host: www.grinderschool.com User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 (.NET CLR 3.5.30729) Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 115 Connection: keep-alive Referer: http://www.grinderschool.com/phpBB3/viewtopic.php?f=14&p=29468 Cookie: style_cookie=printonly; phpbb3_7c544_u=2; phpbb3_7c544_k=44b832912e5f887d; phpbb3_7c544_sid=e8852df42e08cc1b2250300c2897f78f; __utma=174624884.2719561324781918700.1251850714.1270986325.1270989003.575; __utmz=174624884.1264524375.411.12.utmcsr=google|utmccn=(organic)|utmcmd=organic|utmctr=low%20stakes%20poker%20videos; phpbb3_cmviy_k=; phpbb3_cmviy_u=2; phpbb3_cmviy_sid=d8df5c0943863004ca40ef9c392d371d; __utmb=174624884.4.10.1270989003; __utmc=174624884 Pragma: no-cache Cache-Control: no-cache HTTP/1.1 200 OK Date: Sun, 11 Apr 2010 12:57:41 GMT Server: Apache/2.2.14 (Unix) mod_ssl/2.2.14 OpenSSL/0.9.8l DAV/2 mod_auth_passthrough/2.1 FrontPage/5.0.2.2635 Last-Modified: Sun, 04 Apr 2010 12:51:06 GMT Etag: "eb42d6-7d9b843-48368aa6dc280" Accept-Ranges: bytes Content-Length: 131708995 Keep-Alive: timeout=10, max=30 Connection: Keep-Alive Content-Type: video/x-ms-wmv And here's what they look like for the request answered by my script: http://www.grinderschool.com/download_video_test.php?t=KillsAids021&format=wmv GET /download_video_test.php?t=KillsAids021&format=wmv HTTP/1.1 Host: www.grinderschool.com User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 (.NET CLR 3.5.30729) Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 115 Connection: keep-alive Cookie: style_cookie=printonly; phpbb3_7c544_u=2; phpbb3_7c544_k=44b832912e5f887d; phpbb3_7c544_sid=e8852df42e08cc1b2250300c2897f78f; __utma=174624884.2719561324781918700.1251850714.1270986325.1270989003.575; __utmz=174624884.1264524375.411.12.utmcsr=google|utmccn=(organic)|utmcmd=organic|utmctr=low%20stakes%20poker%20videos; phpbb3_cmviy_k=; phpbb3_cmviy_u=2; phpbb3_cmviy_sid=d8df5c0943863004ca40ef9c392d371d; __utmb=174624884.4.10.1270989003; __utmc=174624884 HTTP/1.1 200 OK Date: Sun, 11 Apr 2010 12:58:02 GMT Server: Apache/2.2.14 (Unix) mod_ssl/2.2.14 OpenSSL/0.9.8l DAV/2 mod_auth_passthrough/2.1 FrontPage/5.0.2.2635 X-Powered-By: PHP/5.2.11 Content-Disposition: attachment; filename=KillsAids021.wmv Vary: Accept-Encoding Content-Encoding: gzip Keep-Alive: timeout=10, max=30 Connection: Keep-Alive Transfer-Encoding: chunked Content-Type: video/x-ms-wmv So the question is...what can I do to make downloads from the script work properly? Again, for 99% of users, it works as is (though I find it annoying now that no filesize is reported and thus that no time estimate can be computed about the download).

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• Problem with SQL syntax (probably simple)

  - by Bryan Folds

  I'm doing some custom database work for a module for Drupal and I get the following SQL error when trying to create my table: user warning: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DEFAULT NULL, rooms INT DEFAULT NULL, adults INT DEFAULT NULL, children' at line 14 query: CREATE TABLE dr_enquiry ( eId INT unsigned NOT NULL auto_increment, eKey VARCHAR(16) NOT NULL, dateSent INT NOT NULL DEFAULT 0, status VARCHAR(30) NOT NULL DEFAULT 'Unanswered', custName VARCHAR(50) NOT NULL, custEmail VARCHAR(200) NOT NULL, custPhone VARCHAR(25) NOT NULL, custCountry VARCHAR(40) NOT NULL, custIP VARCHAR(11) DEFAULT NULL, offerName VARCHAR(100) NOT NULL, offerURL VARCHAR(200) NOT NULL, arrival DATETIME DEFAULT NULL, departure DEFAULT NULL, rooms INT DEFAULT NULL, adults INT DEFAULT NULL, children INT DEFAULT NULL, childAges VARCHAR(32) DEFAULT NULL, toddlers INT DEFAULT NULL, toddlerAges VARCHAR(32) DEFAULT NULL, catering VARCHAR(255) DEFAULT NULL, comments VARCHAR(255) DEFAULT NULL, agent VARCHAR(100) DEFAULT NULL, voucher VARCHAR(100) DEFAULT NULL, PRIMARY KEY (eId) ) /*!40100 DEFAULT CHARACTER SET UTF8 */ in /home/travelco/public_html/includes/database.inc on line 550.

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• Ranking/ weighing search result

  - by biso

  I am trying to build an application that has a smart adaptive search engine (lets say for cars). If I search for for 4x4 then the DB will return all the 4x4 cars I have (100 cars) - but as time goes by and I start checking out cars, liking them, commenting on them, etc the order of the search result should be the different. That means 1 month later when searching for 4x4, I should get the same result set ordered differently as per my previous interaction with the site. If I was mainly liking and commenting on German cars, BMW should be on the top and Land cruiser should be further down. This ranking should be based on attributes that I captureduring user interaction (eg: car origin, user age, user location, car type[4x4, coupe, hatchback], price range). So for each car result I get, I will be weighing it based on how well it is performing on the 5 attributes above. I intend to use the DB just as a repository and do the ranking and the thinking on the server. My question is, what kind of algorithm should I be using to weigh/rank my search result? Thanks.

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• What is the optimum way to secure a company wide wiki?

  - by Mark Robinson

  We have a wiki which is used by over half our company. Generally it has been very positively received. However, there is a concern over security - not letting confidential information fall into the wrong hands (i.e. competitors). The default answer is to create a complicated security matrix defining who can read what document (wiki page) based on who created it. Personally I think this mainly solves the wrong problem because it creates barriers within the company instead of a barrier to the external world. But some are concerned that people at a customer site might share information with a customer which then goes to the competitor. The administration of such a matrix is a nightmare because (1) the matrix is based on department and not projects (this is a matrix organisation), and (2) because in a wiki all pages are by definition dynamic so what is confidential today might not be confidential tomorrow (but the history is always readable!). Apart from the security matrix, we've considered restricting content on the wiki to non super secret stuff, but off course that needs to be monitored. Another solution (the current) is to monitor views and report anything suspicious (e.g. one person at a customer site having 2000 views in two days was reported). Again - this is not ideal because this does not directly imply a wrong motive. Does anyone have a better solution? How can a company wide wiki be made secure and yet keep its low threshold USP? BTW we use MediaWiki with Lockdown to exclude some administrative staff.

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• Can LINQ expression classes implement the observer pattern instead of deferred execution?

  - by Tormod

  Hi. We have issues within an application using a state machine. The application is implemented as a windows service and is iteration based (it "foreaches" itself through everything) and there are myriads of instances being processed by the state machine. As I'm reading the MEAP version of Jon Skeets book "C# in Depth, 2nd ed", I'm wondering if I can change the whole thing to use linq expression instances so that guards and conditions are represented using expression trees. We are building many applications on this state machine engine and would probably greatly benefit from the new Expression tree visualizer in VS 2010 Now, simple example. If I have an expression tree where there is an OR Expression condition with two sub nodes, is there any way that these can implement the observer pattern so that the expression tree becomes event driven? If a condition change, it should notify its parent node (the OR node). Since the OR node then changes from "false" to "true", then it should notify ITS parent and so on. I love the declarative model of expression trees, but the deferred execution model works in opposite direction of the control flow if you want event based "live" conditions. Am I off on a wild goose chase here? Or is there some concept in the BCL that may help me achieve this?

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• capture delete key in CListCtrl and do soem processing

  - by user333422

  Hi, I have a class which inherits from CListCtrl class, say class list. I have another class dlg, which inherits from CDialog. Class dlg contains an instance of class list. I have got a delete button in class dlg, on which I delete the selected item in listCtrl and do lots of other processing. I want the same functionality on delete key. I added OnKeyDown() fn is my class list, where I can capture VK_DELETE key. But my problem is that, how do I do otehr processing that I need to do in dialog class. All that processing is dlg class based not list class based. I have many such dlg classes with different data and in every dlg class processing is different. I tried capturing VK_DELETE in dialog class, but it doesn't capture it if focus is on list class. I am totally stuck and have no idea, how to do this. Please give me some idea how i can do this. Thanks, SG

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• Flex 4 / Flash 4 Add to Current State

  - by user163757

  I am having a little difficulty working with states in Flex (or Flash) 4. Lets say that my application has three states; the default (base) state, state 1, and state 2. State 1 should always be based on the base state, that's easy enough to accomplish. However, I would like state 2 to be based on the current state (either base or state 1). I can't for the life of me figure it out. I tried setting the basedOn property of state 1 to "this.currentState", but that just crashes my browser. <s:states> <s:State name="default"/> <s:State name="state1"/> <s:State name="state2" basedOn="{this.currentState}"/> </s:states> <s:TitleWindow id="configWindow" includeIn="state1" width="250" height="100%" close="configWindow_closeHandler(event)"/> <s:Panel id="settings" includeIn="state2" width="200" height="200"/>

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• Looking for all-in-one drm/installer/CD creation kit.

  - by user30997

  The company I work for has a download manager in place that handles distribution, DRM, installation of our products - when a user gets them off our website. However, we're using an clunky system for packaging and protecting our products when we do press releases or make retail CDs. Part of the antiquation problem is the fact that the automated system that works with the installer- and DRM-creation software we have is a disaster that needs to be put out of my misery. The list of products that we currently produce, that I would like a new system MUST be capable of producing: Retail CDs, with a certain level of obfuscation to make copying difficult. Downloadable installers that time out after a few hours of use of the product. After the time has expired, removing and reinstalling the product will leave you still blocked from use. Installers that will fail to work after a certain date. I'd love to be able to just feed a tool the directory where a complete product resides and have the installer generated with a couple command-line operations. (The command-line issue is non-negotiable this well be called by an automated tool.) A single-solution package would be far preferable. Software with royalty-based or per-unit based licensing is not an option.

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• java runtime tracing library to replace system.out.println

  - by Grzegorz Oledzki

  Have you heard of any library which would allow me to set up a tracing for specific methods at runtime? Instead of adding (and removing) lots of System.out.println in my code (and having to re-compile and re-deploy) I would like to have a magic thing which would print out a line for each call of selected method without any change in the code. This would work without re-compiling, so some kind of JVM agent (or some non-standard JVM would be needed?). Sounds like a job for aspect programming? A typical scenario would be to start an application, configure the traced methods dynamically (in a separate file or similar) and then everytime a selected method is called a line with its name (and arguments) is printed out to System.out (or some log file). Naturally one could think of tens of additional features, but this basic set would be a great tool. BTW, I use Eclipse interactive debugger too, not only the System.out tracing technique, but both have some advantages and sometimes Eclipse is not enough.

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• How can I force a jQuery faded-in user control to remain after click events?

  - by David

  I have a basic page to which I'm adding an uploader control based on Bulk Uploader at c-sharpcorner.com and the control is in a jQuery-faded div based on yesdegisn The Bulk Uploader has two server side event handlers for two buttons--Add and Remove. After clicking these buttons, the fade disappears and you're back to the basic page--if the user needs to add more files, this is not desirable. The ArrayList of files added to a ListBox is maintained, but I have to click the "fade-in" link (LinkButton id="lnkDocumentUpload") to display this window again. I also need the control to POST to UploadPost.aspx, and it doesn't work either. Clicking the upload button(<asp:Button ID="btnUpload" runat="server" />) has the same behavior described above--fade disappears, data is retained, and no POST. I've surrounded the control with <form id="frmUpload" action="~/UploadPost.aspx"> ... <asp:Button ID="btnUpload" runat="server" Text="Upload"/> </form> A LinkButton activates the fade in jQuery via $("#lnkDocumentUpload").click(function() { centerPopup(); loadPopup(); });

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• Testing a Gui-heavy WPF application.

  - by Hamish Grubijan

  We (my colleagues) have a messy 12 y.o. mature app that is GUI-based, and the current plan is to add new dialogs & other GUI in WPF, as well as replace some of the older dialogs in WPF as well. At the same time we wish to be able to test that Monster - GUI automation in a maintainable way. Some challenges: The application is massive. It constantly gains new features. It is being changed around (bug fixes, patches). It has a back end, and a layer in-between. The state of it can get out of whack if you beat it to death. What we want is: Some tool that can automate testing of WPF. auto-discovery of what the inputs and the outputs of the dialog are. An old test should still work if you add a label that does nothing. It should fail, however, if you remove a necessary text field. It would be very nice if the test suite was easy to maintain, if it ran and did not break most of the time. Every new dialog should be created with testability in mind. At this point I do not know exactly what I want, so I am marking this as a community wiki. If having to test a huge GUI-based app rings the bell (even if not in WPF), then please share your good, bad and ugly experiences here.

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• Button outside view... how to make it work

  - by Mike

  I have a UIImageView based class that creates objects with the following characteristics: a small image square and a UITextView below. If the user drags the object by the image it can drag it around. If the user taps on the UITextView the keyboard has to appear and the user can change the text on it. The objects created by the class are like this: 1) the object creates a 60x60 pixels frame 2) puts an image inside that frame 3) creates a UITextView and puts it below that 60x60 frame. So, as the class is a UIImageView based and it creates an image with 60x60 pixels and the UITextView is located outside that area, in theory the text view is outside the area the tapping are for that object. Obviously I could make the class create a big square to encompass the image and the text view, but that frame would be too big and I have the objects created by this class to be as close as possible when I add them to another view. I could also create the text views from the same view I created the objects, but I would have to manage each object and each correspondent text view and I need them to move together... so, I have a problem. Any ideas on a simplest way to do that?

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• Project Management and Scheduling Techniques

  - by Alec Smart

  Hello, I know this is probably the nth project management question. But am trying to move my team onto a more robust project management technique. Am wondering what is the best technique to use? I know that probably no technique is best, but which are the most popular techniques? Poker planning? Evidence Based Scheduling? COCOMO? Agile? Scrum? XP? Which one to use? Also, suppose I use EBS, wouldn't it be too time consuming to break down every single activity into fine grained tasks? E.g. "Design" is a goal, what kind of fine-grained tasks will I have under it? Is this is a waste of time i.e. dividing work into so many micro parts. Usually when I give my programmers a task, I follow up every week, and they complete quite a lot of the task assigned to them (the tasks are very broad e.g. X module). Is EBS worth it? Are there any white-papers on it so that I can implement it on my own? (instead of using Fogbugz) Most of my projects are web-based projects. Thank you for your time.

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• How to make a request from an android app that can enter a Spring Security secured webservice method

  - by johnrock

  I have a Spring Security (form based authentication) web app running CXF JAX-RS webservices and I am trying to connect to this webservice from an Android app that can be authenticated on a per user basis. Currently, when I add an @Secured annotation to my webservice method all requests to this method are denied. I have tried to pass in credentials of a valid user/password (that currently exists in the Spring Security based web app and can log in to the web app successfully) from the android call but the request still fails to enter this method when the @Secured annotation is present. The SecurityContext parameter returns null when calling getUserPrincipal(). How can I make a request from an android app that can enter a Spring Security secured webservice method? Here is the code I am working with at the moment: Android call: httpclient.getCredentialsProvider().setCredentials( //new AuthScope("192.168.1.101", 80), new AuthScope(null, -1), new UsernamePasswordCredentials("joeuser", "mypassword")); String userAgent = "Android/" + getVersion(); HttpGet httpget = new HttpGet(MY_URI); httpget.setHeader("User-Agent", userAgent); httpget.setHeader("Content-Type", "application/xml"); HttpResponse response; try { response = httpclient.execute(httpget); HttpEntity entity = response.getEntity(); ... parse xml Webservice Method: @GET @Path("/payload") @Produces("application/XML") @Secured({"ROLE_USER","ROLE_ADMIN","ROLE_GUEST"}) public Response makePayload(@Context Request request, @Context SecurityContext securityContext){ Payload payload = new Payload(); payload.setUsersOnline(new Long(200)); if (payload == null) { return Response.noContent().build(); } else{ return Response.ok().entity(payload).build(); } }

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• Summation loop program in Pascal

  - by user2526598

  I am having a bit of an issue with this problem. I am taking a Pascal programming class and this problem was in my logic book. I am required to have the user enter a series of (+) numbers and once he/she enters a (-) number, the program should find the sum of all the (+) numbers. I accomplished this, but now I am attempting part two of this problem, which requires me to utilize a nested loop to run the program x amount of times based on the user's input. The following code is what I have so far and honestly I am stumped: program summation; //Define main program's variables var num, sum, numRun : integer; //Design procedure that will promt user for number of runs procedure numRunLoop ( var numRun : integer ); begin writeln('How many times shall I run this program?'); readln(numRun); end; //Design procedure that will sum a series of numbers //based on user input procedure numPromptLoop( numRun : integer; var num : integer ); var count : integer; begin //Utilize for to establish run limit for count := 1 to numRun do begin //Use repeat to prompt user for numbers repeat writeln('Enter a number: '); readln(num); //Tells program when to sum if num >= 0 then sum := sum + num; until num < 0; end; end; //Design procedure that will display procedure addItion( sum : integer ); begin writeln('The sum is; ', sum); end; begin numRunLoop(numRun); numPromptloop(numRun, num); addItion(sum); readln(); end.

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• Is there a way to implement Caliburn-like co-routines in VB.NET since there's no yield keyword

  - by Miroslav Popovic

  Note that I'm aware of other yield in vb.net questions here on SO. I'm playing around with Caliburn lately. Bunch of great stuff there, including co-routines implementation. Most of the work I'm doing is C# based, but now I'm also creating an architecture guideline for a VB.NET only shop, based on Rob's small MVVM framework. Everything looks very well except using co-routines from VB. Since VB 10 is used, we can try something like Bill McCarthy's suggestion: Public Function Lines(ByVal rdr as TextReader) As IEnumerable(Of String) Return New GenericIterator(Of String) (Function(ByRef nextItem As String) As Boolean nextItem = rdr.ReadLine Return nextItem IsNot Nothing End Function) End Function I'm just failing to comprehend how a little more complex co-routine method like the one below (taken from Rob's GameLibrary) could be written in VB: public IEnumerable<IResult> ExecuteSearch() { var search = new SearchGames { SearchText = SearchText }.AsResult(); yield return Show.Busy(); yield return search; var resultCount = search.Response.Count(); if (resultCount == 0) SearchResults = _noResults.WithTitle(SearchText); else if (resultCount == 1 && search.Response.First().Title == SearchText) { var getGame = new GetGame { Id = search.Response.First().Id }.AsResult(); yield return getGame; yield return Show.Screen<ExploreGameViewModel>() .Configured(x => x.WithGame(getGame.Response)); } else SearchResults = _results.With(search.Response); yield return Show.NotBusy(); } Any idea how to achieve that, or any thoughts on using Caliburn co-routines in VB?

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• how to Compute the average probe length for success and failure - Linear probe (Hash Tables)

  - by fang_dejavu

  hi everyone, I'm doing an assignment for my Data Structures class. we were asked to to study linear probing with load factors of .1, .2 , .3, ...., and .9. The formula for testing is: The average probe length using linear probing is roughly Success-- ( 1 + 1/(1-L)**2)/2 or Failure-- (1+1(1-L))/2. we are required to find the theoretical using the formula above which I did(just plug the load factor in the formula), then we have to calculate the empirical (which I not quite sure how to do). here is the rest of the requirements **For each load factor, 10,000 randomly generated positive ints between 1 and 50000 (inclusive) will be inserted into a table of the "right" size, where "right" is strictly based upon the load factor you are testing. Repeats are allowed. Be sure that your formula for randomly generated ints is correct. There is a class called Random in java.util. USE it! After a table of the right (based upon L) size is loaded with 10,000 ints, do 100 searches of newly generated random ints from the range of 1 to 50000. Compute the average probe length for each of the two formulas and indicate the denominators used in each calculationSo, for example, each test for a .5 load would have a table of size approximately 20,000 (adjusted to be prime) and similarly each test for a .9 load would have a table of approximate size 10,000/.9 (again adjusted to be prime). The program should run displaying the various load factors tested, the average probe for each search (the two denominators used to compute the averages will add to 100), and the theoretical answers using the formula above. .** how do I calculate the empirical success?

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• IIS Restrict Access to Directory for table of users

  - by Dave

  I am trying to restrict access to files in a directory and it's sub directories based user rights. My user rights are stored in an MS SQL database in a custom format, however it is easy to query the list of users with rights to this directory. I need to know how to apply this to a web config on the server to authenticate against a query of a database table to determine if the username is authenticated and allowed to view the file. Of course if they are not they should be blocked / given a 404. I am using IIS and ASP.Net MVC3 with a form based security as opposed to the built in roles and responsibilities that was custom made for us and that works great. There are over 10k users tied to this non-Active Directory authentication so I am not planning to change my authentication type so please don't go there. It is not my decision on the choice of platform, or I would have gone with a LAMP server and been done with this. Edit 11-13-2012 @ 8:57a: In the web config can you put the result of an SQL query?

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• How to model parent to child pair in MySQL (SQL)

  - by mikeschuld

  I have a data model that includes element types Stage, Actor, and Form. Logically, Stages can be assigned pairs of ( Form <--- Actor ) which can be duplicated many times (i.e. same person and same form added to the same stage at a later date/time). Right now I am modeling this with these tables: Stage Form Actor Form_Actor _______________ |Id | |FormId | --> Id in Form |ActorId | --> Id in Actor Stage_FormActor __________________ |Id | |StageId | --> Id in Stage |FormActorId | --> Id in Form_Actor I am using CodeSmith to generate the data layer for this setup and none of the templates really know how to handle this type of relationship correctly when generating classes. Ideally, the ORM would have Stage.FormActors where FormActor would be the pair Form, Actor. Is this the correct way to model these relationships. I have tried using all three Ids in one table as well Stage_Form_Actor ______________ |Id | |StageId | --> Id in Stage |FormId | --> Id in Form |ActorId | --> Id in Actor This doesn't really get generated very well either. Ideas?

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• error in a pygame code

  - by mekasperasky

  # INTIALISATION import pygame, math, sys from pygame.locals import * screen = pygame.display.set_mode((1024, 768)) car = pygame.image.load('car.png') clock = pygame.time.Clock() k_up = k_down = k_left = k_right = 0 speed = direction = 0 position = (100, 100) TURN_SPEED = 5 ACCELERATION = 2 MAX_FORWARD_SPEED = 10 MAX_REVERSE_SPEED = ­5 BLACK = (0,0,0) while 1: # USER INPUT clock.tick(30) for event in pygame.event.get(): if not hasattr(event, 'key'): continue down = event.type == KEYDOWN # key down or up? if event.key == K_RIGHT: k_right = down * ­5 elif event.key == K_LEFT: k_left = down * 5 elif event.key == K_UP: k_up = down * 2 elif event.key == K_DOWN: k_down = down * ­2 elif event.key == K_ESCAPE: sys.exit(0) # quit the game screen.fill(BLACK) # SIMULATION # .. new speed and direction based on acceleration and turn speed += (k_up + k_down) if speed > MAX_FORWARD_SPEED: speed = MAX_FORWARD_SPEED if speed < MAX_REVERSE_SPEED: speed = MAX_REVERSE_SPEED direction += (k_right + k_left) # .. new position based on current position, speed and direction x, y = position rad = direction * math.pi / 180 x += ­speed*math.sin(rad) y += ­speed*math.cos(rad) position = (x, y) # RENDERING # .. rotate the car image for direction rotated = pygame.transform.rotate(car, direction) # .. position the car on screen rect = rotated.get_rect() rect.center = position # .. render the car to screen screen.blit(rotated, rect) pygame.display.flip() enter code here the error i get is this Non-ASCII character '\xc2' in file race1.py on line 13, but no encoding declared; see http://www.python.org/peps/pep-0263.html for details Not able to understand what the error is and how to get rid of it?

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• Populating a foreign key table with variable user input

  - by Vincent

  I'm working on a website that will be based on user contributed data, submitted using a regular HTML form. To simplify my question, let's say that there will be two fields in the form: "User Name" and "Country" (this is just an example, not the actual site). There will be two tables in the database : "countries" and "users," with "users.country_id" being a foreign key to the "countries" table (one-to-many). The initial database will be empty. Users from all over the world will submit their names and the countries they live in and eventually the "countries" table will get filled out with all of the country names in the world. Since one country can have several alternative names, input like Chile, Chili, Chilli will generate 3 different records in the countries table, but in fact there is only one country. When I search for records from Chile, Chili and Chilli will not be included. So my question is - what would be the best way to deal with a situation like this, with conditions such that the initial database is empty, no other resources are available and everything is based on user input? How can I organize it in such way that Chile, Chili and Chilli would be treated as one country, with minimum manual interference. What are the best practices when it comes to normalizing user submitted data and is there a scientific term for this? I'm sure this is a common problem. Again, I used country names just to simplify my question, it can be anything that has possible different spellings.

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• Encrypt a file base upon a pregenerated "key" C#

  - by Anubis

  Hello everyone. I'm trying to determine the best course of action to implement a simple "licensing" system with a partner of mine. The concept is: Generate an encrypted value based upon several internal hardware components. Have the customer send this value to us which we will implement into our key generator. Once we have that, we add any other restrictions on the license (user, expires, etc.). From there we generate a file which we send to the customer they can add to their installation and voila, happy people about. I have the first part all done. My next part is trying to figure out which encryption methodology I would need to use. I already know Symmetric Encryption is pretty much the only route I can take. Most of the information I have found involves .NET already creating a key from its own internal methods. That's a bit of background, my question is: "Which encryption method could I use which would allow me to encrypt the restrictions based upon the "id" I was given from the customer's computer?" I'm writing this in C# by the way. Any ideas would be greatly appreciated! Take Care!

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