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• CodePlex Daily Summary for Wednesday, May 12, 2010

  CodePlex Daily Summary for Wednesday, May 12, 2010New ProjectsAMP (Adamo Media Player): AMP is a custom media player that specializes in large media collections! Change the way you manage your media!BoogiePartners: BoogiePartners provides a loose collection of utilities or extensions for Boogie and SpecSharp developers.C# Developer Utility Library: Collection of helpful code functions including zero-config rolling file logging, parameter validation, reflection & object construction, I18N count...Commerce Server 2009 Orders using Pipelines in a Console Application: Using Commerce Server 2009 outside of a Web Application this project show how to create dummy Orders using Pipelines in a NON WEB CONTEXT, an examp...CRM Queue Manager C#: CRM 4 Queue Manager written in C#. Based on the original VB.Net CRM Queue Manager with some changes, additions and feature changes. Converts emai...DbBuilder: This is a tool indended for creation of MS SQL database from scratch, incremental updates, management of redeployable objects, etc. using scripted ...DbNetData: A collection of cross vendor database interface classes for .NET written in C# providing a consistent and simplified way of accessing SQL Server,Or...Deploy Workflow Manager: Kick off a workflow associated with a SharePoint List on all list items at once. SharePoint Designer Workflows will also be included. This projec...DigiLini - digital on screen ruler: Handy desktop tool for everyone who does ever do something graphical on his computer. There is an sizable horizontal and vertial ruler. You can pos...Dynamic Grid Data Type for Umbraco: The Dynamic Grid Data Type for Umbraco is a custom ASCX/C# control that was created to store tabular data as an Umbraco "Data Type". There's an abi...FlashPlus: An extension for Google Chrome and a bookmarklet for Internet Explorer and Firefox, this project makes media content on browsers more usable. This...Flat Database: Simple project making it really quick and easy, to implement a simple flat-file database for an application.Flood Watch Spam Control: Flood watch is a C# based application meant to help prevent site black listings. This application monitors outbound smtp streams, if a stream excee...Gamebox: gameboxKill Bill: Kill Bill covers the areas of customers, suppliers, products, sales and administration divided into modules which together form the system for the ...KND Decoder: Der KND Decoder konvertiert die lästigen Zahlenwerte, in den Java Dateien vom Knuddels Applet, zu lesbaren Strings. Die neue dekodier Methode wurde...Moonbeam: D3D11 FrameworkSite Defender: Add-on for blogs or anywhere else there could be people spamming your website.sMODfix: -Stringzilla: A string formatting classes designed for .NET 4 to enable named string formatting and conditional string formatting options based upon bound data c...The CQRS Kitchen: The CQRS Kitchen is an example application build with Silverlight 4 that demonstrates how to implement a CQRS / Event Sourcing application with the...XELF Framework for XNA / .NET: XELF Framework for XNA / .NET 　XNA Game Studioおよび.NET Framework用のライブラリ・フレームワークとしてXELFが開発したC#ソースコードを含むプロジェクトです。 　現在は、「XELF.Framework」のWindows用XNA G...xxxxxxxxx: xxxxxxxNew ReleasesASP.NET MVC 2 - CommonLibrary.CMS: CommonLibrary CMS - Alpha: CommonLibrary CMSA simple yet powerful CMS system in ASP.NET MVC 2 using C# 3.5. ActiveRecord based support for Blogs, Widgets, Pages, Parts, Ev...ASP.NET MVC Extensions: v1.0 RTM: v1.0 RTMAWS SimpleDB Browser: Release 2: Miscellaneous fixes from the Alpha release. Built to work with the released version of the .Net Framework 4.0.BIDS Helper: 1.4.3.0: This release addresses the following issues: For some people the BIDS Helper extensions to the Project Properties page for the SSIS Deploy plugin w...Bojinx: Bojinx Core V4.5.13: Fixes / Enhancements: Sequencer now accepts Commands directly without using events. Command queue now accepts both events and commands EventBu...CF-Soft: TestCases_DROP1: TestCases_DROP1CodePlex Runtime Intelligence Integration: PreEmptive.Attributes distributable: Contains a signed redistributable version of the PreEmptive.Attributes.dll library that non .NET 4 applications can use support in-code instrumenta...Convection Game Engine (Basic Edition): Convection Basic (44772): Compiled version of Convection Basic change set 44772.CRM Queue Manager C#: Initial release: Initial release of the CRM Queue Manager in C#. Release includes both the installer as well as the latest source code in zippped format. Running...DbNetData: DbNetData.1.0: Initial releaseDigiLini - digital on screen ruler: DigiLini 1.0: First stable version.Facturator - Create invoices easy and fast: Facturator.zip: current stable versionFlat Database: Initial Release: This is the working initial release of FlatDBKharaPOS: MSDN Magazine Sample: This is the release that supports the MSDN magazine article "Enterprise Patterns with WCF RIA Services. Some of the project was affected by the upg...Let's Up: 1.1 (Build 100511): - Add short and long break feature.Mesopotamia Experiment: Mesopotamia 1.2.88: Primarly bug fixes... Bug Fixes - fixed bug in synapse mutating whereby new ones were of one side only eg, source or target - fixed bug in screen ...NodeXL: Network Overview, Discovery and Exploration for Excel: NodeXL Class Libraries, version 1.0.1.123: The NodeXL class libraries can be used to display network graphs in .NET applications. To include a NodeXL network graph in a WPF desktop or Windo...NodeXL: Network Overview, Discovery and Exploration for Excel: NodeXL Excel 2007 Template, version 1.0.1.123: The NodeXL Excel 2007 template displays a network graph using edge and vertex lists stored in an Excel 2007 workbook. What's NewThis version makes...Over Store: OverStore 1.18.0.0: Version number is increased. New callback events added: Persisting and Persisted, which are raised on actually writing object data into the stora...Reusable Library: V1.0.7: A collection of reusable abstractions for enterprise application developerReusable Library Demo: V1.0.5: A demonstration of reusable abstractions for enterprise application developerRuntime Intelligence Endpoint Starter Kit: Runtime Intelligence Endpoint Starter Kit 20100511: Added crossdomain policy files so Silverlight applications can send usage data from anywhere.Scorm2CC: SCORM2CC Release 0.12.0.58711 net-2.0 Alpha: SCORM2CC Release 0.12.0.58711 net-2.0 AlphaShake - C# Make: Shake v0.1.14: Updated API to match with the current documentation.SharePoint LogViewer: SharePoint Log Viewer 2.6: This is a maintenance release. It has bug several fixes.Site Directory for SharePoint 2010 (from Microsoft Consulting Services, UK): v1.4: As 1.3 with the following changes Addition of a 'Site Data' webpart Site Directory can now be a site collection root or sub-site Scan job now ...sMODfix: sMODfix v1.0: Basic Versionsmtp4dev: smtp4dev 2.0: Smtp4dev 2.0 is powered by a completely re-written server component and now offers SSL/TLS and AUTH support.SocialScapes: SocialScapes Sidebar 1.0: The SocialScapes Sidebar is the first release of the new SocialScapes suite. There will be more modules to come along with a complete data aggrega...SSIS Multiple Hash: Multiple Hash V1.2: This is version 1.2 of the Multiple Hash SSIS Component. It supports SQL 2005 and SQL 2008, although you have to download the correct install pack...Surfium: Beta build: Somehow testedTerminals: Terminals 1.9a - RDP6 Support: The major change in this release is that Terminals has been upgraded to require RDP Client 6 to be installed for creating RDP connections. Backward...TFS Compare: Release 3.0: This release provides a new feature - the ability to navigate back and forth between document differences. Also, this release provides support for...VCC: Latest build, v2.1.30511.0: Automatic drop of latest buildyoutubeFisher: youtubeFisher v2.0: What's new new method of youtube parameters capturing HD 720p video support full-HD 1080p video support add Cancel option to stop file downl...Most Popular ProjectsWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesPHPExcelASP.NETMost Active Projectspatterns & practices – Enterprise LibraryMirror Testing SystemRawrThe Information Literacy Education Learning Environment (ILE)Caliburn: An Application Framework for WPF and SilverlightwhiteBlogEngine.NETPHPExceljQuery Library for SharePoint Web ServicesTweetSharp

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• Queued Loadtest to remove Concurrency issues using Shared Data Service in OpenScript

  - by stefan.thieme(at)oracle.com

  Queued Processing to remove Concurrency issues in Loadtest ScriptsSome scripts act on information returned by the server, e.g. act on first item in the returned list of pending tasks/actions. This may lead to concurrency issues if the virtual users simulated in a load test scenario are not synchronized in some way.As the load test cases should be carried out in a comparable and straight forward manner simply cancel a transaction in case a collision occurs is clearly not an option. In case you increase the number of virtual users this approach would lead to a high number of requests for the early steps in your transaction (e.g. login, retrieve list of action points, assign an action point to the virtual user) but later steps would be rarely visited successfully or at all, depending on the application logic.A way to tackle this problem is to enqueue the virtual users in a Shared Data Service queue. Only the first virtual user in this queue will be allowed to carry out the critical steps (retrieve list of action points, assign an action point to the virtual user) in your transaction at any one time.Once a virtual user has passed the critical path it will dequeue himself from the head of the queue and continue with his actions. This does theoretically allow virtual users to run in parallel all steps of the transaction which are not part of the critical path.In practice it has been seen this is rarely the case, though it does not allow adding more than N users to perform a transaction without causing delays due to virtual users waiting in the queue. N being the time of the total transaction divided by the sum of the time of all critical steps in this transaction.While this problem can be circumvented by allowing multiple queues to act on individual segments of the list of actions, e.g. per country filter, ends with 0..9 filter, etc.This would require additional handling of these additional queues of slots for the virtual users at the head of the queue in order to maintain the mutually exclusive access to the first element in the list returned by the server at any one time of the load test. Such an improved handling of multiple queues and/or multiple slots is above the subject of this paper.Shared Data Services Pre-RequisitesStart WebLogic Server to host Shared Data ServicesYou will have to make sure that your WebLogic server is installed and started. Shared Data Services may not work if you installed only the minimal installation package for OpenScript. If however you installed the default package including OLT and OTM, you may follow the instructions below to start and verify WebLogic installation.To start the WebLogic Server deployed underneath of Oracle Load Testing and/or Oracle Test Manager you can go to your Start menu, Oracle Application Testing Suite and select the Restart Oracle Application Testing Suite Application Service entry from the Tools submenu.To verify the service has been started you can run the Microsoft Management Console for Services by Selecting Run from the Start Menu and entering services.msc. Look for the entry that reads Oracle Application Testing Suite Application Service, once it has changed it status from Starting to Started you can proceed to verify the login. Please note that this may take several minutes, I would say up to 10 minutes depending on the strength of your CPU horse-power.Verify WebLogic Server user credentialsYou will have to make sure that your WebLogic Server is installed and started. Next open the Oracle WebLogic Server Adminstration Console on http://localhost:8088/console.It may take a while until the application is deployed and started. It may display the following until the Administration Console has been deployed on the fly.Afterwards you can login using the username oats and the password that you selected during install time for your Application Testing Suite administrative purposes.This will bring up the Home page of you WebLogic Server. You have actually verified that you are able to login with these credentials already. However if you want to check the details, navigate to Security Realms, myrealm, Users and Groups tab.Here you could add users to your WebLogic Server which could be used in the later steps. Details on the Groups required for such a custom user to work are exceeding this quick overview and have to be selected with the WebLogic Server Adminstration Guide in mind.Shared Data Services pre-requisites for Load testingOpenScript Preferences have to be set to enable Encryption and provide a default Shared Data Service Connection for Playback.These are pre-requisites you want to use for load testing with Shared Data Services.Please note that the usage of the Connection Parameters (individual directive in the script) for Shared Data Services did not playback reliably in the current version 9.20.0370 of Oracle Load Testing (OLT) and encryption of credentials still seemed to be mandatory as well.General Encryption settingsSelect OpenScript Preferences from the View menu and navigate to the General, Encryption entry in the tree on the left. Select the Encrypt script data option from the list and enter the same password that you used for securing your WebLogic Server Administration Console.Enable global shared data access credentialsSelect OpenScript Preferences from the View menu and navigate to the Playback, Shared Data entry in the tree on the left. Enable the global shared data access credentials and enter the Address, User name and Password determined for your WebLogic Server to host Shared Data Services.Please note, that you may want to replace the localhost in Address with the hosts realname in case you plan to run load tests with Loadtest Agents running on remote systems.Queued Processing of TransactionsEnable Shared Data Services Module in Script PropertiesThe Shared Data Services Module has to be enabled for each Script that wants to employ the Shared Data Service Queue functionality in OpenScript. It can be enabled under the Script menu selecting Script Properties. On the Script Properties Dialog select the Modules section and check Shared Data to enable Shared Data Service Module for your script. Checking the Shared Data Services option will effectively add a line to your script code that adds the sharedData ScriptService to your script class of IteratingVUserScript.@ScriptService oracle.oats.scripting.modules.sharedData.api.SharedDataService sharedData;Record your scriptRecord your script as usual and then add the following things for Queue handling in the Initialize code block, before the first step and after the last step of your critical path and in the Finalize code block.The java code to be added at individual locations is explained in the following sections in full detail.Create a Shared Data Queue in InitializeTo create a Shared Data Queue go to the Java view of your script and enter the following statements to the initialize() code block.info("Create queueA with life time of 120 minutes");sharedData.createQueue("queueA", 120);This will create an instantiation of the Shared Data Queue object named queueA which is maintained for upto 120 minutes.If you want to use the code for multiple scripts, make sure to use a different queue name for each one here and in the subsequent steps. You may even consider to use a dynamic queueName based on filters of your result list being concurrently accessed.Prepare a unique id for each IterationIn order to keep track of individual virtual users in our queue we need to create a unique identifier from the virtual user id and the used username right after retrieving the next record from our databank file.getDatabank("Usernames").getNextDatabankRecord();getVariables().set("usernameValue1","VU_{{@vuid}}_{{@iterationnum}}_{{db.Usernames.Username}}_{{@timestamp}}_{{@random(10000)}}");String usernameValue = getVariables().get("usernameValue1");info("Now running virtual user " + usernameValue);As you can see from the above code block, we have set the OpenScript variable usernameValue1 to VU_{{@vuid}}_{{@iterationnum}}_{{db.Usernames.Username}}_{{@timestamp}}_{{@random(10000)}} which is a concatenation of the virtual user id and the iterationnumber for general uniqueness; as well as the username from our databank, the timestamp and a random number for making it further unique and ease spotting of errors.Not all of these fields are actually required to make it really unique, but adding the queue name may also be considered to help troubleshoot multiple queues.The value is then retrieved with the getVariables.get() method call and assigned to the usernameValue String used throughout the script.Please note that moving the getDatabank("Usernames").getNextDatabankRecord(); call to the initialize block was later considered to remove concurrency of multiple virtual users running with the same userid and therefor accessing the same "My Inbox" in step 6. This will effectively give each virtual user a userid from the databank file. Make sure you have enough userids to remove this second hurdle.Enqueue and attend Queue before Critical PathTo maintain the right order of virtual users being allowed into the critical path of the transaction the following pseudo step has to be added in front of the first critical step. In the case of this example this is right in front of the step where we retrieve the list of actions from which we select the first to be assigned to us.beginStep("[0] Waiting in the Queue", 0);{info("Enqueued virtual user " + usernameValue + " at the end of queueA");sharedData.offerLast("queueA", usernameValue);info("Wait until the user is the first in queueA");String queueValue1 = null;do {// we wait for at least 0.7 seconds before we check the head of the// queue. This is the time it takes one user to move through the// critical path, i.e. pass steps [5] Enter country and [6] Assign// to meThread.sleep(700);queueValue1 = (String) sharedData.peekFirst("queueA");info("The first user in queueA is currently: '" + queueValue1 + "' " + queueValue1.getClass() + " length " + queueValue1.length() );info("The current user is '"+ usernameValue + "' " + usernameValue.getClass() + " length " + usernameValue.length() + ": indexOf " + usernameValue.indexOf(queueValue1) + " equals " + usernameValue.equals(queueValue1) );} while ( queueValue1.indexOf(usernameValue) < 0 );info("Now the user is the first in queueA");}endStep();This will enqueue the username to the tail of our Queue. It will will wait for at least 700 milliseconds, the time it takes for one user to exit the critical path and then compare the head of our queue with it's username. This last step will be repeated while the two are not equal (indexOf less than zero). If they are equal the indexOf will yield a value of zero or larger and we will perform the critical steps.Dequeue after Critical PathAfter the virtual user has left the critical path and complete its last step the following code block needs to dequeue the virtual user. In the case of our example this is right after the action has been actually assigned to the virtual user. This will allow the next virtual user to retrieve the list of actions still available and in turn let him make his selection/assignment.info("Get and remove the current user from the head of queueA");String pollValue1 = (String) sharedData.pollFirst("queueA");The current user is removed from the head of the queue. The next one will now be able to match his username against the head of the queue.Clear and Destroy Queue for FinishWhen the script has completed, it should clear and destroy the queue. This code block can be put in the finish block of your script and/or in a separate script in order to clear and remove the queue in case you have spotted an error or want to reset the queue for some reason.info("Clear queueA");sharedData.clearQueue("queueA");info("Destroy queueA");sharedData.destroyQueue("queueA");The users waiting in queueA are cleared and the queue is destroyed. If you have scripts still executing they will be caught in a loop.I found it better to maintain a separate Reset Queue script which contained only the following code in the initialize() block. I use to call this script to make sure the queue is cleared in between multiple Loadtest runs. This script could also even be added as the first in a larger scenario, which would execute it only once at very start of the Loadtest and make sure the queues do not contain any stale entries.info("Create queueA with life time of 120 minutes");sharedData.createQueue("queueA", 120);info("Clear queueA");sharedData.clearQueue("queueA");This will create a Shared Data Queue instance of queueA and clear all entries from this queue.Monitoring QueueWhile creating the scripts it was useful to monitor the contents, i.e. the current first user in the Queue. The following code block will make sure the Shared Data Queue is accessible in the initialize() block.info("Create queueA with life time of 120 minutes");sharedData.createQueue("queueA", 120);In the run() block the following code will continuously monitor the first element of the Queue and write an informational message with the current username Value to the Result window.info("Monitor the first users in queueA");String queueValue1 = null;do {queueValue1 = (String) sharedData.peekFirst("queueA");if (queueValue1 != null)info("The first user in queueA is currently: '" + queueValue1 + "' " + queueValue1.getClass() + " length " + queueValue1.length() );} while ( true );This script can be run from OpenScript parallel to a loadtest performed by the Oracle Load Test.However it is not recommend to run this in a production loadtest as the performance impact is unknown. Accessing the Queue's head with the peekFirst() method has been reported with about 2 seconds response time by both OpenScript and OTL. It is advised to log a Service Request to see if this could be lowered in future releases of Application Testing Suite, as the pollFirst() and even offerLast() writing to the tail of the Queue usually returned after an average 0.1 seconds.Debugging QueueWhile debugging the scripts the following was useful to remove single entries from its head, i.e. the current first user in the Queue. The following code block will make sure the Shared Data Queue is accessible in the initialize() block.info("Create queueA with life time of 120 minutes");sharedData.createQueue("queueA", 120);In the run() block the following code will remove the first element of the Queue and write an informational message with the current username Value to the Result window.info("Get and remove the current user from the head of queueA");String pollValue1 = (String) sharedData.pollFirst("queueA");info("The first user in queueA was currently: '" + pollValue1 + "' " + pollValue1.getClass() + " length " + pollValue1.length() );ReferencesOracle Functional Testing OpenScript User's Guide Version 9.20 [E15488-05]Chapter 17 Using the Shared Data Modulehttp://download.oracle.com/otn/nt/apptesting/oats-docs-9.21.0030.zipOracle Fusion Middleware Oracle WebLogic Server Administration Console Online Help 11g Release 1 (10.3.4) [E13952-04]Administration Console Online Help - Manage users and groupshttp://download.oracle.com/docs/cd/E17904_01/apirefs.1111/e13952/taskhelp/security/ManageUsersAndGroups.htm

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• Option Trading: Getting the most out of the event session options

  - by extended_events

  You can control different aspects of how an event session behaves by setting the event session options as part of the CREATE EVENT SESSION DDL. The default settings for the event session options are designed to handle most of the common event collection situations so I generally recommend that you just use the defaults. Like everything in the real world though, there are going to be a handful of “special cases” that require something different. This post focuses on identifying the special cases and the correct use of the options to accommodate those cases. There is a reason it’s called Default The default session options specify a total event buffer size of 4 MB with a 30 second latency. Translating this into human terms; this means that our default behavior is that the system will start processing events from the event buffer when we reach about 1.3 MB of events or after 30 seconds, which ever comes first. Aside: What’s up with the 1.3 MB, I thought you said the buffer was 4 MB?The Extended Events engine takes the total buffer size specified by MAX_MEMORY (4MB by default) and divides it into 3 equally sized buffers. This is done so that a session can be publishing events to one buffer while other buffers are being processed. There are always at least three buffers; how to get more than three is covered later. Using this configuration, the Extended Events engine can “keep up” with most event sessions on standard workloads. Why is this? The fact is that most events are small, really small; on the order of a couple hundred bytes. Even when you start considering events that carry dynamically sized data (eg. binary, text, etc.) or adding actions that collect additional data, the total size of the event is still likely to be pretty small. This means that each buffer can likely hold thousands of events before it has to be processed. When the event buffers are finally processed there is an economy of scale achieved since most targets support bulk processing of the events so they are processed at the buffer level rather than the individual event level. When all this is working together it’s more likely that a full buffer will be processed and put back into the ready queue before the remaining buffers (remember, there are at least three) are full. I know what you’re going to say: “My server is exceptional! My workload is so massive it defies categorization!” OK, maybe you weren’t going to say that exactly, but you were probably thinking it. The point is that there are situations that won’t be covered by the Default, but that’s a good place to start and this post assumes you’ve started there so that you have something to look at in order to determine if you do have a special case that needs different settings. So let’s get to the special cases… What event just fired?! How about now?! Now?! If you believe the commercial adage from Heinz Ketchup (Heinz Slow Good Ketchup ad on You Tube), some things are worth the wait. This is not a belief held by most DBAs, particularly DBAs who are looking for an answer to a troubleshooting question fast. If you’re one of these anxious DBAs, or maybe just a Program Manager doing a demo, then 30 seconds might be longer than you’re comfortable waiting. If you find yourself in this situation then consider changing the MAX_DISPATCH_LATENCY option for your event session. This option will force the event buffers to be processed based on your time schedule. This option only makes sense for the asynchronous targets since those are the ones where we allow events to build up in the event buffer – if you’re using one of the synchronous targets this option isn’t relevant. Avoid forgotten events by increasing your memory Have you ever had one of those days where you keep forgetting things? That can happen in Extended Events too; we call it dropped events. In order to optimizes for server performance and help ensure that the Extended Events doesn’t block the server if to drop events that can’t be published to a buffer because the buffer is full. You can determine if events are being dropped from a session by querying the dm_xe_sessions DMV and looking at the dropped_event_count field. Aside: Should you care if you’re dropping events?Maybe not – think about why you’re collecting data in the first place and whether you’re really going to miss a few dropped events. For example, if you’re collecting query duration stats over thousands of executions of a query it won’t make a huge difference to miss a couple executions. Use your best judgment. If you find that your session is dropping events it means that the event buffer is not large enough to handle the volume of events that are being published. There are two ways to address this problem. First, you could collect fewer events – examine you session to see if you are over collecting. Do you need all the actions you’ve specified? Could you apply a predicate to be more specific about when you fire the event? Assuming the session is defined correctly, the next option is to change the MAX_MEMORY option to a larger number. Picking the right event buffer size might take some trial and error, but a good place to start is with the number of dropped events compared to the number you’ve collected. Aside: There are three different behaviors for dropping events that you specify using the EVENT_RETENTION_MODE option. The default is to allow single event loss and you should stick with this setting since it is the best choice for keeping the impact on server performance low.You’ll be tempted to use the setting to not lose any events (NO_EVENT_LOSS) – resist this urge since it can result in blocking on the server. If you’re worried that you’re losing events you should be increasing your event buffer memory as described in this section. Some events are too big to fail A less common reason for dropping an event is when an event is so large that it can’t fit into the event buffer. Even though most events are going to be small, you might find a condition that occasionally generates a very large event. You can determine if your session is dropping large events by looking at the dm_xe_sessions DMV once again, this time check the largest_event_dropped_size. If this value is larger than the size of your event buffer [remember, the size of your event buffer, by default, is max_memory / 3] then you need a large event buffer. To specify a large event buffer you set the MAX_EVENT_SIZE option to a value large enough to fit the largest event dropped based on data from the DMV. When you set this option the Extended Events engine will create two buffers of this size to accommodate these large events. As an added bonus (no extra charge) the large event buffer will also be used to store normal events in the cases where the normal event buffers are all full and waiting to be processed. (Note: This is just a side-effect, not the intended use. If you’re dropping many normal events then you should increase your normal event buffer size.) Partitioning: moving your events to a sub-division Earlier I alluded to the fact that you can configure your event session to use more than the standard three event buffers – this is called partitioning and is controlled by the MEMORY_PARTITION_MODE option. The result of setting this option is fairly easy to explain, but knowing when to use it is a bit more art than science. First the science… You can configure partitioning in three ways: None, Per NUMA Node & Per CPU. This specifies the location where sets of event buffers are created with fairly obvious implication. There are rules we follow for sub-dividing the total memory (specified by MAX_MEMORY) between all the event buffers that are specific to the mode used: None: 3 buffers (fixed)Node: 3 * number_of_nodesCPU: 2.5 * number_of_cpus Here are some examples of what this means for different Node/CPU counts: Configuration None Node CPU 2 CPUs, 1 Node 3 buffers 3 buffers 5 buffers 6 CPUs, 2 Node 3 buffers 6 buffers 15 buffers 40 CPUs, 5 Nodes 3 buffers 15 buffers 100 buffers   Aside: Buffer size on multi-processor computersAs the number of Nodes or CPUs increases, the size of the event buffer gets smaller because the total memory is sub-divided into more pieces. The defaults will hold up to this for a while since each buffer set is holding events only from the Node or CPU that it is associated with, but at some point the buffers will get too small and you’ll either see events being dropped or you’ll get an error when you create your session because you’re below the minimum buffer size. Increase the MAX_MEMORY setting to an appropriate number for the configuration. The most likely reason to start partitioning is going to be related to performance. If you notice that running an event session is impacting the performance of your server beyond a reasonably expected level [Yes, there is a reasonably expected level of work required to collect events.] then partitioning might be an answer. Before you partition you might want to check a few other things: Is your event retention set to NO_EVENT_LOSS and causing blocking? (I told you not to do this.) Consider changing your event loss mode or increasing memory. Are you over collecting and causing more work than necessary? Consider adding predicates to events or removing unnecessary events and actions from your session. Are you writing the file target to the same slow disk that you use for TempDB and your other high activity databases? <kidding> <not really> It’s always worth considering the end to end picture – if you’re writing events to a file you can be impacted by I/O, network; all the usual stuff. Assuming you’ve ruled out the obvious (and not so obvious) issues, there are performance conditions that will be addressed by partitioning. For example, it’s possible to have a successful event session (eg. no dropped events) but still see a performance impact because you have many CPUs all attempting to write to the same free buffer and having to wait in line to finish their work. This is a case where partitioning would relieve the contention between the different CPUs and likely reduce the performance impact cause by the event session. There is no DMV you can check to find these conditions – sorry – that’s where the art comes in. This is  largely a matter of experimentation. On the bright side you probably won’t need to to worry about this level of detail all that often. The performance impact of Extended Events is significantly lower than what you may be used to with SQL Trace. You will likely only care about the impact if you are trying to set up a long running event session that will be part of your everyday workload – sessions used for short term troubleshooting will likely fall into the “reasonably expected impact” category. Hey buddy – I think you forgot something OK, there are two options I didn’t cover: STARTUP_STATE & TRACK_CAUSALITY. If you want your event sessions to start automatically when the server starts, set the STARTUP_STATE option to ON. (Now there is only one option I didn’t cover.) I’m going to leave causality for another post since it’s not really related to session behavior, it’s more about event analysis. - Mike Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• CodePlex Daily Summary for Thursday, May 13, 2010

  CodePlex Daily Summary for Thursday, May 13, 2010New ProjectsC# 4.0: VS 2010Collaborative Rich Text Edit Prototype Silverlight on Windows Azure: Working like Google Doc but based on Silverlight/Windows Azure. Multiple users can edit one rich text document simultaneously. This is a POC and my...Consulting Assigment: Proyecto de consultoría para el curso Gestión de proyectos de la UCRCS 105 MP Splitter: Simple program to help with splitting up MPs for grading.DipEngine - graphic engine written on Xen for XNA: DIPEngine makes it easier for developers to use it in your game. It's developed in C# and using Xen for XNADotNetAgent: Agent FrameworkExtending C# editor - Outlining, classification: Extensions to VS C# editor current feautereset. Outlining for switch, for(each), if etc. statements. Classification types for method parameters and...Floe IRC Client: Floe is an IRC client written entirely in C#, using the .NET 4.0 framework with WPF technology. It is inspired largely by both XChat and mIRC, and ...Gestalt.Net: Gestalt.Net is a simple to use library for application configuration. It allows for more flexibility, easier to use, and more powerful than the app...GIM.OnlineChess: An implementation of online long-term chessGoogleTrail: Create and Export using the google map to develop the Trek Trails and Export Those Trails as Garmin Custom Map Compatible MapsGrassidi: What could Grassidi be?HodsAudio: Personal web based music library.Hospital Manage System: Free Hospital Manage SystemHtml Reader: Html Reader makes it easier for WPF WebBrowser users to access the Document property, and retrieve information from HTML pages. You'll no longer ha...Intellitouch.BackOffice: This project is a control for a menu.Jank: JankKooBoo Image Galery: It's a Module for kooboo that implements an image galery admin and view Developed for kooboo 2.1.1.0MoonyDesk (windows desktop widgets): Windows desktop plugin based widgets system written on WPFMSNSharp Application with Video Conferencing Feature: In MSN World, users don’t communicate directly each other.I examined P2P open source video/audio conference systems . After researching, I found Vi...mysample: study sample siteNoteFlyBot: An Intelligent Note Program is: - a 'Post-it' note that accept sNatural Language command to Upload content to EMC Repositories - Start Workflow...OpenGraphNET: A OpenGraphNET is a simple parser for the Open Graph protocol created by Facebook. More information on this can be found at opengraphprotocol.org.POCO - ADO.NET Entity Framework 4.0: The sample shows how to retrieve the data using POCO using EDM 4.0. Database used: Northwind (http://www.microsoft.com/downloads/details.aspx?Fa...sqlmx: sqlmxUpgrade Log Parser for SharePoint 2010: This is a simple Upgrade Log Parser for SharePoint 2010. It will add a node in the upgrade section of the central administration and deploy a pag...New ReleasesAMP (Adamo Media Player): AMP (Adamo Media Player): First Release version 0.1.0 Installation Instructions Unzip the package Run Setup.exe Follow Setup instructions File includes .NET Framework ...BeanProxy: BeanProxy 2.8: BeanProxy is a C# (.NET 3.5) library housing classes that facilitates unit testing. Any non-static, public interface/class/or abstract class can be...Begtostudy-Test: Test V1: Download to testCBM-Command: 2010-05-13: Release Notes - 2010-05-13New Features Configuration Manager is complete Changes Had to put CBM-Command on a big-time diet. Ran out of room on the...CS 105 MP Splitter: CS 105 MP Splitter: Uses SharpZipLib for unzipping (http://www.icsharpcode.net/OpenSource/SharpZipLib/) Uses ILMerge to merge it all into a single executable (http://w...DipEngine - graphic engine written on Xen for XNA: DipGUI: Provides simple controls for use itEvent Scavenger: Collector service update - version 3.2.3: Added additional functionality to check if host/machine is available on the network before trying to open Event log. Also added code to try to use ...ExcelExportLib: ExcelExportLib 1.4.0.0: Solution converted to Visual Studio 2010 - Added support for formulas in cells - Added support for cell naming - Added support for cell's comments...F# Project Extender: V0.9.1.0 (VS2008,VS2010): F# project extender for Visual Studio 2008 and Visual Studio 2010. What's new : Now supports both Visual Studio 2010 and Visual Studio 2008 Fixed...Floe IRC Client: Floe IRC Client 2010-05: Initial release. Note: The .NET Framework v4.0 is required to run this app. It can be downloaded here: http://www.microsoft.com/downloads/details....Fluent Assertions: Release 1.2.1: This is small release with two improvements: You can now use the Enumeration() extension method on a Func<IEnumerable> before calling ShouldThrow<T...Gestalt.Net: Gestalt.Net 1.0: Initial release of Gestalt.Net, a simple to use library for application configuration. It allows for more flexibility, easier to use, and more powe...GPdotNET - Tree Based Genetic Programming Tool: GPdotNETv0.9: This is the same version as previous, but compiled with Visual Studio 2010 and .NET 4.0. You no longer need CTP of ParallelFX.HKGolden Express: HKGoldenExpress (Build 201005122025): New features: (None) Bug fix: (None) Improvements: HKGolden Express now parse JSON data rather than XML document from HKGolden API. This shoul...Jobping Url Shortener: Deploy Code 0.3: Contains only the files for running 0.3 version of the code.Jobping Url Shortener: Source Code 0.3: Feature added: Restriction placed on the domains that the shortener will shorten. Our installation will only shorten www.jobping.com urls. Bug Fix...KooBoo Image Galery: Beta 1: This is the first release and it is divided in some parts Module Install - Is the admin module and an default view Plugin - returns the galery as...LinkedIn® for Windows Mobile: LinkedIn for Windows Mobile v0.8.5: Changes in release 0.8.5 Allow for multiple updatetypes. Add search by Company. Show profiles of all people in an update .MDownloader: MDownloader-0.15.13.58780: Fixed Uploading.com dead links detection; Fixed links detection at pages and in FilesTube results; Fixed RSS channel checking; Enabled by def...Microsoft - Domain Oriented N-Layered .NET 4.0 App Sample (Microsoft Spain): V0.8 - N-Layer DDD Sample App (VS.2010 RTM compat): Required Software (Microsoft Base Software needed for Development environment) Visual Studio 2010 RTM & .NET 4.0 RTM (Final Versions) Unity Applic...MoonyDesk (windows desktop widgets): MoonyDesk: MoonyDesk alpha releaseMSNSharp Application with Video Conferencing Feature: MSNVideoChat: Msn Video Chat Application's exe and screenshot is attached.NazTek.Extension.Clr35: NazTek.Extension.Clr35 Binary: FxCop compliant codebaseNazTek.Extension.Clr35: NazTek.Extension.Clr35 Signed Binary: Signed binaryNazTek.Extension.Clr35: NazTek.Extension.Clr35 Signed Source: Signed sourceNazTek.Extension.Clr35: NazTek.Extension.Clr35 Source: FxCop compliant codebasepatterns & practices Web Client Developer Guidance: Web Client Software Factory 2010 Guide: If the right-side pane of the chm file is not displayed correctly, do the following: 1) Download WCSF2010Guide.chm file. 2) Start the windows explo...Powershell Scripts for Admins: BizTalk PowerShell Module: BizTalk PowerShell Module Available commands : Get-Applications Start-Application Stop-Application Get-HostInstances Start-HostInstance Stop-Hos...Reusable Library: V1.0.8: A collection of reusable abstractions for enterprise application developerReusable Library Demo: V1.0.6: A demonstration of reusable abstractions for enterprise application developerRobot Shootans: Robot Shootans 0.9: This is the second public release of the game. All instructions for play are in the game itself. Known issues: Bullet collision is still a little...Rx Contrib: V1.2: - Bug fix - API changes public static ReactiveQueue<T> CreateConcurrentQueue( ConcurrentPublicationBehavior concurrentPublicationBeha...SqlDiffFramework-A Visual Differencing Engine for Dissimilar Data Sources: SqlDiffFramework 1.0.1.0: Maintenance Release An embedded user control inadvertently assumed US regional and language settings; with non-US settings the application crashed ...Transcriber: Transcriber V0.5.0: Pre-releaseUpgrade Log Parser for SharePoint 2010: Upgrade Log Parser for SharePoint 2010: Introduction I did an upgrade from MOSS 2007 to SharePoint 2010 and SP2010 generated such a large log file and I really didn't feel like scrolling ...VCC: Latest build, v2.1.30512.0: Automatic drop of latest buildVisual Leak Detector for Visual C++ 2008/2010: v2.0a: Renamed vld dll files. Problem with MSVC 2010 Unicode library fixed.VsTortoise - a TortoiseSVN add-in for Microsoft Visual Studio: VsTortoise Build 24 Beta: Build 24 (beta) New: Added "Open Modified File..." to Solution Explorer context menus. VsTortoise.SolutionExplorerSelectedItemsOpenModifiedFile com...WatchersNET.TagCloud: WatchersNET.TagCloud 01.05.00: Whats New Custom Tags: Tag Name and Tag Url can be localized New Option to set Start Date to grab Search Referrals from New Option to Choose th...Wavelet analysis: Wavelet analysis: Первая публичная версия проекта.XNA Shooter Engine: ModelViewer Alpha 1 Preview: ModelViewer is a utility for previewing HLSL shaders and XNA BasicEffects using the XSE rendering engine. It can also be used with the Microsoft XN...Yet another developer blog - Examples: XML and XSLT transformation in ASP.NET MVC example: This sample application shows how to perform XSL transformation of XML file in ASP.NET MVC (using dedicated HtmlHelper extensions or ActionResult)....Most Popular ProjectsWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesPHPExcelASP.NETMost Active Projectspatterns & practices – Enterprise LibraryMirror Testing SystemRawrBlogEngine.NETPHPExcelwhitejQuery Library for SharePoint Web ServicesMicrosoft Biology FoundationFarseer Physics EngineShake - C# Make

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• CodePlex Daily Summary for Tuesday, April 13, 2010

  CodePlex Daily Summary for Tuesday, April 13, 2010New ProjectsChat Neo: Video chatDev-wow HappyFuwa: Silverlight + Asp.net + Ajax 实现的以北京奥运为题材，福娃在线聊天互动系统 登录系统后，你可以和线上的朋友即时互动，走动 聊天 动作等都会呈现给其他的在线用户Dynamic Configuration Manager: Dynamic Configuration Manager GameHelper: the project of myselfGeotron: Geotron is a C# geolocation library to resolve postcodes and addresses to co-ordinates, to assist developers in creating location-aware applications. InfoPath Forms Services 2010 Web Testing Toolkit: This project has the tools and information needed to write Visual Studio web tests for InfoPath Forms Services 2010.IronBrainFuck, SimpleBrainFuck: IronBrainFuck and SimpleBrainFuck makes it easier for BrainFuck programmers to develop BrainFuck-compatible programs. It's developed in C#.Runtime Intelligence API: The Runtime Intelligence API library and samples provided by PreEmptive Solutions.SilverVNC 1.0: This project is a Silverlight VNC Viewer. It requires Silverlight 4.0 and works in Out of Browser with full-trust.Snippet Creator: Yet another Visual Studio plugin for creating code snippets.Software Codex: Software Codex is a collection of projects developed in .net to provide a set of libraries and functionalities for developers. It is divided into m...TestCrm: Let go!Make our CrmVidCoder: VidCoder is a DVD ripping and video transcoding application. It uses HandBrake for the encoding engine, but has a revamped and easy to use UI writt...WPF Data Virtualization: Component for displaying and interacting a large data set in WPF application.WPF Gantt chart: Gantt chart control for WPFNew ReleasesAJAX Control Toolkit: 40412: AJAX Control Toolkit Release Notes - April 12th 2010 Release Version 40412April 12, 2010 release of the AJAX Control Toolkit. AJAX Control Toolkit...ASP.NET MVC | SCAFFOLD: ASP.NET MVC SCAFFOLD 1.0 PREVIEW: Primeiro release do ASP.NET MVC SCAFFOLD.Autenticar no OpenLDAP utilizando pGIna: LDAPAuth plugin: Release: DLL LDAPAuth Brief: pGina pluginBluetooth Radar: Version 1.8: Add position helper class to test whether a given point is on the interior of a circle. Random set of Devices on the radar + Zindex changes on Mous...Database Searcher: DB-Searcher Binaries v0.1: First beta version containing following features: Search exact database values via .NET DB-Provider Microsoft SQL MySQL .NET Connector (no .NET t...DBSourceTools: DBSourceTools_1.2.0.7: Release 1.2.0.7 Extended search engine from (pegas)'s patch. Fixed Script Data bug with reserved word (eripsni). Write Targets can now create targe...ESB Toolkit Extensions: Tellago SOA ESB Extenstions v0.4: Windows Installer file that installs Library on a BizTalk ESB 2.0 system. This Install automatically configures the esb.config to use the new compo...Fluent Assertions: Release 1.2: See this blog post for more details on this release: http://www.dennisdoomen.net/2010/04/fluent-assertions-12-has-been-released.htmlFNA Fractal Numerical Algorithm for a new encryption technology: FNA: This is a latest distribution ( 0.04 at the moment). Is a Perl package (.pm). More information on: http://search.cpan.org/~anak/Free Silverlight & WPF Chart Control - Visifire: Visifire SL and WPF Charts 3.0.6 Released!: Hi, Today we have released the final version of Visifire v3.0.6 which contains the following major features: * Zoom using interactive ZoomRec...HD-Trailers.NET Downloader: HD-Trailers.NET_Downloader_v.91_BETA: - added configuration option 'FeedAddress' to specify the URL of the RSS feed to consume - implemented fix for workitem4260: AddDate = false; will ...HobbyBrew Mobile: Beta 1: First public BetaHome Access Plus+: v3.2.6.1: v3.2.6.1 Fixed the wrong date in the iCal Generator Fixed the admin booking posting logging it as being booked by the admin Fixed the problem o...HTML Ruby: 6.21.1: Added back the space ruby text option More consistent ruby text positioning regardless to the page's stylesInfoPath Forms Services 2010 Web Testing Toolkit: IPFS 2010 Web Test Toolkit 20100412 for VS2008: The ExtractAndSubstituteDynamicInfoPathData web test plugin. To use it, simply add the plugin to your web test. It automatically recognizes the inf...IronPython: 2.6.1: Hello Python Community, We’re pleased to announce the final release of IronPython 2.6.1. This version of IronPython makes great strides in stabili...IronRuby: 1.0: IronRuby 1.0 is the first stable version of IronRuby, targeting Ruby 1.8.6 compatibility. For a high-level compatibility report solely based on Rub...METAR.NET Decoder: 0.3.x beta: First public release. Main of the application is working. Metar can be downloaded, decoded, updated and encoded back to metar string. Release incl...MiniTwitter: 1.11: MiniTwitter 1.11 更新内容 修正 設定ファイルを自動でバックアップして、破損したときは出来るだけ修正するように。 初回起動時にタイムラインを更新しようとすると落ちるバグを修正。MSBuild Mercurial Tasks: 1.0.1 Stable: Ready for Production release. This version integrates all the basic functionalities of Mercurial as defined in the Use Case 1.Multiplayer Quiz: Release 1_7_0_0: Latest Version Strongly recommended to use .NET 4.0 now that it is in RC It can be downloaded from hereMVC Foolproof Validation: Beta 0.9.3754: First Beta release. Addressed several bugs from alpha along with some considerable class refactoring. ModelAwareValidationAttribute will make creat...NodeXL: Network Overview, Discovery and Exploration for Excel: NodeXL Excel 2007 Template, version 1.0.1.121: The NodeXL Excel 2007 template displays a network graph using edge and vertex lists stored in an Excel 2007 workbook. What's NewThis version allow...Proxi [Proxy Interface]: Proxi Release 1.0.0.412: Proxi Release 1.0.0.412QueryUnit: QueryUnitPOC v. 0.0.0.8: This version add support for AreNotEqual, Greater, Less and fix some problems with "format" attribute used in conjunction with the string data type...Rainier: Trabalhos de orçamento empresarial: Estão disponíveis os arquivos de exemplo sobre o planejamento para orçamento empresarial. A resolução é referente aos exercícios explicados em sal...Runtime Intelligence API: Initial release: The initial release of the WCF contract & proxy assembly. AuthentiCode signed library.SharePoint Accelerators: Central Admin - Command Search: This web part allows you to search for a SharePoint 2010 Central Admin commands. This web part can come handy when you are demostrating SharePoint ...SharePoint Labs: SPLab5013A-FRA-Level100: SPLab5013A-FRA-Level100* This SharePoint Lab will teach you how to provision a computed site column that shows a customized view of an existing hid...SilverVNC 1.0: SilverVNC 1.0.3755.0: This download is the first release of the project published on www.silverlightplayground.org. For a detailed explanation please refer to http://www...Snippet Creator: SnippetCreator.Setup: This is the first and (I hope) final release.SQL Server Health & History (SQLH2): SQLH2 v.2.2.001: New Features Updated to use .Net 3.5 Job and Job history information implemented Last dif and log backup columns added Logical Disk implemented Dis...SQL Server Health & History (SQLH2): SQLH2PerfCollector v.2.1.003: Updated to run on .Net 3.5 Now installs to correct registry path on x64Star Trooper for XNA 2D Tutorial: Lesson one content: Here is Lesson one original content for the StarTrooper 2D XNA tutorial. The blog tutorial has now started over on http://xna-uk.net/blogs/darkgen...SysPad: SysPad 4.10.7.1: A folder management and scratchpad utility; especially useful in a business network setting that utilizes numerous, commonly used folders. The pro...TaskUnZip for SSIS: TaskUnZip for SSIS 1.1.0.0: Add: recursive compress. Add: filter option for exstract e compress file. (Tnx to: Kevin Wendler)TCP Wrapper: TCP Wrapper 1.0.0.3: Adding Client Accessor to CommingDataAvailableEventArgs ...UCD: Architecture: UCDArch 1.0: Production release of UCDArch 1.0 (for ASP.NET MVC 1.0). New Features including the ability to modify the NHibernate FlushMode, URL convention help...VCC: Latest build, v2.1.30412.0: Automatic drop of latest buildVidCoder: 0.1.0: First VidCoder beta release. It's missing a few features that will be added before release: Advanced x264 options In-GUI encode log Additiona...WatchersNET CKEditor™ Provider for DotNetNuke: CKEditor Provider 1.10.01: Whats New changesBrowser: Removed extra "\" sign from Current folder name selecting the root folder Browser: Fixed Folder Rendering Browser Fix...WPF Gantt chart: gantt: first, alpha version, of gantt chart for wpfxvanneste: Coverflow et thumbnail sharepoint: Code du coverflow silverlight du webcast sur les thumbnails sharepointMost Popular ProjectsWBFS ManagerRawrMicrosoft SQL Server Product Samples: DatabaseAJAX Control ToolkitSilverlight ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesFacebook Developer ToolkitPHPExcelMost Active ProjectsRawrnopCommerce. Open Source online shop e-commerce solution.AutoPocopatterns & practices – Enterprise LibraryShweet: SharePoint 2010 Team Messaging built with PexFarseer Physics EngineNB_Store - Free DotNetNuke Ecommerce Catalog ModuleIonics Isapi Rewrite FilterBlogEngine.NETBeanProxy

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• Investigation: Can different combinations of components effect Dataflow performance?

  - by jamiet

  Introduction The Dataflow task is one of the core components (if not the core component) of SQL Server Integration Services (SSIS) and often the most misunderstood. This is not surprising, its an incredibly complicated beast and we’re abstracted away from that complexity via some boxes that go yellow red or green and that have some lines drawn between them. Example dataflow In this blog post I intend to look under that facade and get into some of the nuts and bolts of the Dataflow Task by investigating how the decisions we make when building our packages can affect performance. I will do this by comparing the performance of three dataflows that all have the same input, all produce the same output, but which all operate slightly differently by way of having different transformation components. I also want to use this blog post to challenge a common held opinion that I see perpetuated over and over again on the SSIS forum. That is, that people assume adding components to a dataflow will be detrimental to overall performance. Its not surprising that people think this –it is intuitive to think that more components means more work- however this is not a view that I share. I have always been of the opinion that there are many factors affecting dataflow duration and the number of components is actually one of the less important ones; having said that I have never proven that assertion and that is one reason for this investigation. I have actually seen evidence that some people think dataflow duration is simply a function of number of rows and number of components. I’ll happily call that one out as a myth even without any investigation!  The Setup I have a 2GB datafile which is a list of 4731904 (~4.7million) customer records with various attributes against them and it contains 2 columns that I am going to use for categorisation: [YearlyIncome] [BirthDate] The data file is a SSIS raw format file which I chose to use because it is the quickest way of getting data into a dataflow and given that I am testing the transformations, not the source or destination adapters, I want to minimise external influences as much as possible. In the test I will split the customers according to month of birth (12 of those) and whether or not their yearly income is above or below 50000 (2 of those); in other words I will be splitting them into 24 discrete categories and in order to do it I shall be using different combinations of SSIS’ Conditional Split and Derived Column transformation components. The 24 datapaths that occur will each input to a rowcount component, again because this is the least resource intensive means of terminating a datapath. The test is being carried out on a Dell XPS Studio laptop with a quad core (8 logical Procs) Intel Core i7 at 1.73GHz and Samsung SSD hard drive. Its running SQL Server 2008 R2 on Windows 7. The Variables Here are the three combinations of components that I am going to test:     One Conditional Split - A single Conditional Split component CSPL Split by Month of Birth and income category that will use expressions on [YearlyIncome] & [BirthDate] to send each row to one of 24 outputs. This next screenshot displays the expression logic in use: Derived Column & Conditional Split - A Derived Column component DER Income Category that adds a new column [IncomeCategory] which will contain one of two possible text values {“LessThan50000”,”GreaterThan50000”} and uses [YearlyIncome] to determine which value each row should get. A Conditional Split component CSPL Split by Month of Birth and Income Category then uses that new column in conjunction with [BirthDate] to determine which of the same 24 outputs to send each row to. Put more simply, I am separating the Conditional Split of #1 into a Derived Column and a Conditional Split. The next screenshots display the expression logic in use: DER Income Category         CSPL Split by Month of Birth and Income Category       Three Conditional Splits - A Conditional Split component that produces two outputs based on [YearlyIncome], one for each Income Category. Each of those outputs will go to a further Conditional Split that splits the input into 12 outputs, one for each month of birth (identical logic in each). In this case then I am separating the single Conditional Split of #1 into three Conditional Split components. The next screenshots display the expression logic in use: CSPL Split by Income Category         CSPL Split by Month of Birth 1& 2       Each of these combinations will provide an input to one of the 24 rowcount components, just the same as before. For illustration here is a screenshot of the dataflow containing three Conditional Split components: As you can these dataflows have a fair bit of work to do and remember that they’re doing that work for 4.7million rows. I will execute each dataflow 10 times and use the average for comparison. I foresee three possible outcomes: The dataflow containing just one Conditional Split (i.e. #1) will be quicker There is no significant difference between any of them One of the two dataflows containing multiple transformation components will be quicker Regardless of which of those outcomes come to pass we will have learnt something and that makes this an interesting test to carry out. Note that I will be executing the dataflows using dtexec.exe rather than hitting F5 within BIDS. The Results and Analysis The table below shows all of the executions, 10 for each dataflow. It also shows the average for each along with a standard deviation. All durations are in seconds. I’m pasting a screenshot because I frankly can’t be bothered with the faffing about needed to make a presentable HTML table. It is plain to see from the average that the dataflow containing three conditional splits is significantly faster, the other two taking 43% and 52% longer respectively. This seems strange though, right? Why does the dataflow containing the most components outperform the other two by such a big margin? The answer is actually quite logical when you put some thought into it and I’ll explain that below. Before progressing, a side note. The standard deviation for the “Three Conditional Splits” dataflow is orders of magnitude smaller – indicating that performance for this dataflow can be predicted with much greater confidence too. The Explanation I refer you to the screenshot above that shows how CSPL Split by Month of Birth and salary category in the first dataflow is setup. Observe that there is a case for each combination of Month Of Date and Income Category – 24 in total. These expressions get evaluated in the order that they appear and hence if we assume that Month of Date and Income Category are uniformly distributed in the dataset we can deduce that the expected number of expression evaluations for each row is 12.5 i.e. 1 (the minimum) + 24 (the maximum) divided by 2 = 12.5. Now take a look at the screenshots for the second dataflow. We are doing one expression evaluation in DER Income Category and we have the same 24 cases in CSPL Split by Month of Birth and Income Category as we had before, only the expression differs slightly. In this case then we have 1 + 12.5 = 13.5 expected evaluations for each row – that would account for the slightly longer average execution time for this dataflow. Now onto the third dataflow, the quick one. CSPL Split by Income Category does a maximum of 2 expression evaluations thus the expected number of evaluations per row is 1.5. CSPL Split by Month of Birth 1 & CSPL Split by Month of Birth 2 both have less work to do than the previous Conditional Split components because they only have 12 cases to test for thus the expected number of expression evaluations is 6.5 There are two of them so total expected number of expression evaluations for this dataflow is 6.5 + 6.5 + 1.5 = 14.5. 14.5 is still more than 12.5 & 13.5 though so why is the third dataflow so much quicker? Simple, the conditional expressions in the first two dataflows have two boolean predicates to evaluate – one for Income Category and one for Month of Birth; the expressions in the Conditional Split in the third dataflow however only have one predicate thus they are doing a lot less work. To sum up, the difference in execution times can be attributed to the difference between: MONTH(BirthDate) == 1 && YearlyIncome <= 50000 and MONTH(BirthDate) == 1 In the first two dataflows YearlyIncome <= 50000 gets evaluated an average of 12.5 times for every row whereas in the third dataflow it is evaluated once and once only. Multiply those 11.5 extra operations by 4.7million rows and you get a significant amount of extra CPU cycles – that’s where our duration difference comes from. The Wrap-up The obvious point here is that adding new components to a dataflow isn’t necessarily going to make it go any slower, moreover you may be able to achieve significant improvements by splitting logic over multiple components rather than one. Performance tuning is all about reducing the amount of work that needs to be done and that doesn’t necessarily mean use less components, indeed sometimes you may be able to reduce workload in ways that aren’t immediately obvious as I think I have proven here. Of course there are many variables in play here and your mileage will most definitely vary. I encourage you to download the package and see if you get similar results – let me know in the comments. The package contains all three dataflows plus a fourth dataflow that will create the 2GB raw file for you (you will also need the [AdventureWorksDW2008] sample database from which to source the data); simply disable all dataflows except the one you want to test before executing the package and remember, execute using dtexec, not within BIDS. If you want to explore dataflow performance tuning in more detail then here are some links you might want to check out: Inequality joins, Asynchronous transformations and Lookups Destination Adapter Comparison Don’t turn the dataflow into a cursor SSIS Dataflow – Designing for performance (webinar) Any comments? Let me know! @Jamiet

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• A Look Inside JSR 360 - CLDC 8

  - by Roger Brinkley

  If you didn't notice during JavaOne the Java Micro Edition took a major step forward in its consolidation with Java Standard Edition when JSR 360 was proposed to the JCP community. Over the last couple of years there has been a focus to move Java ME back in line with it's big brother Java SE. We see evidence of this in JCP itself which just recently merged the ME and SE/EE Executive Committees into a single Java Executive Committee. But just before that occurred JSR 360 was proposed and approved for development on October 29. So let's take a look at what changes are now being proposed. In a way JSR 360 is returning back to the original roots of Java ME when it was first introduced. It was indeed a subset of the JDK 4 language, but as Java progressed many of the language changes were not implemented in the Java ME. Back then the tradeoff was still a functionality, footprint trade off but the major market was feature phones. Today the market has changed and CLDC, while it will still target feature phones, will have it primary emphasis on embedded devices like wireless modules, smart meters, health care monitoring and other M2M devices. The major changes will come in three areas: language feature changes, library changes, and consolidating the Generic Connection Framework.  There have been three Java SE versions that have been implemented since JavaME was first developed so the language feature changes can be divided into changes that came in JDK 5 and those in JDK 7, which mostly consist of the project Coin changes. There were no language changes in JDK 6 but the changes from JDK 5 are: Assertions - Assertions enable you to test your assumptions about your program. For example, if you write a method that calculates the speed of a particle, you might assert that the calculated speed is less than the speed of light. In the example code below if the interval isn't between 0 and and 1,00 the an error of "Invalid value?" would be thrown. private void setInterval(int interval) { assert interval > 0 && interval <= 1000 : "Invalid value?" } Generics - Generics add stability to your code by making more of your bugs detectable at compile time. Code that uses generics has many benefits over non-generic code with: Stronger type checks at compile time. Elimination of casts. Enabling programming to implement generic algorithms. Enhanced for Loop - the enhanced for loop allows you to iterate through a collection without having to create an Iterator or without having to calculate beginning and end conditions for a counter variable. The enhanced for loop is the easiest of the new features to immediately incorporate in your code. In this tip you will see how the enhanced for loop replaces more traditional ways of sequentially accessing elements in a collection. void processList(Vector<string> list) { for (String item : list) { ... Autoboxing/Unboxing - This facility eliminates the drudgery of manual conversion between primitive types, such as int and wrapper types, such as Integer.  Hashtable<Integer, string=""> data = new Hashtable<>(); void add(int id, String value) { data.put(id, value); } Enumeration - Prior to JDK 5 enumerations were not typesafe, had no namespace, were brittle because they were compile time constants, and provided no informative print values. JDK 5 added support for enumerated types as a full-fledged class (dubbed an enum type). In addition to solving all the problems mentioned above, it allows you to add arbitrary methods and fields to an enum type, to implement arbitrary interfaces, and more. Enum types provide high-quality implementations of all the Object methods. They are Comparable and Serializable, and the serial form is designed to withstand arbitrary changes in the enum type. enum Season {WINTER, SPRING, SUMMER, FALL}; } private Season season; void setSeason(Season newSeason) { season = newSeason; } Varargs - Varargs eliminates the need for manually boxing up argument lists into an array when invoking methods that accept variable-length argument lists. The three periods after the final parameter's type indicate that the final argument may be passed as an array or as a sequence of arguments. Varargs can be used only in the final argument position. void warning(String format, String... parameters) { .. for(String p : parameters) { ...process(p);... } ... } Static Imports -The static import construct allows unqualified access to static members without inheriting from the type containing the static members. Instead, the program imports the members either individually or en masse. Once the static members have been imported, they may be used without qualification. The static import declaration is analogous to the normal import declaration. Where the normal import declaration imports classes from packages, allowing them to be used without package qualification, the static import declaration imports static members from classes, allowing them to be used without class qualification. import static data.Constants.RATIO; ... double r = Math.cos(RATIO * theta); Annotations - Annotations provide data about a program that is not part of the program itself. They have no direct effect on the operation of the code they annotate. There are a number of uses for annotations including information for the compiler, compiler-time and deployment-time processing, and run-time processing. They can be applied to a program's declarations of classes, fields, methods, and other program elements. @Deprecated public void clear(); The language changes from JDK 7 are little more familiar as they are mostly the changes from Project Coin: String in switch - Hey it only took us 18 years but the String class can be used in the expression of a switch statement. Fortunately for us it won't take that long for JavaME to adopt it. switch (arg) { case "-data": ... case "-out": ... Binary integral literals and underscores in numeric literals - Largely for readability, the integral types (byte, short, int, and long) can also be expressed using the binary number system. and any number of underscore characters (_) can appear anywhere between digits in a numerical literal. byte flags = 0b01001111; long mask = 0xfff0_ff08_4fff_0fffl; Multi-catch and more precise rethrow - A single catch block can handle more than one type of exception. In addition, the compiler performs more precise analysis of rethrown exceptions than earlier releases of Java SE. This enables you to specify more specific exception types in the throws clause of a method declaration. catch (IOException | InterruptedException ex) { logger.log(ex); throw ex; } Type Inference for Generic Instance Creation - Otherwise known as the diamond operator, the type arguments required to invoke the constructor of a generic class can be replaced with an empty set of type parameters (<>) as long as the compiler can infer the type arguments from the context.  map = new Hashtable<>(); Try-with-resource statement - The try-with-resources statement is a try statement that declares one or more resources. A resource is an object that must be closed after the program is finished with it. The try-with-resources statement ensures that each resource is closed at the end of the statement.  try (DataInputStream is = new DataInputStream(...)) { return is.readDouble(); } Simplified varargs method invocation - The Java compiler generates a warning at the declaration site of a varargs method or constructor with a non-reifiable varargs formal parameter. Java SE 7 introduced a compiler option -Xlint:varargs and the annotations @SafeVarargs and @SuppressWarnings({"unchecked", "varargs"}) to supress these warnings. On the library side there are new features that will be added to satisfy the language requirements above and some to improve the currently available set of APIs.  The library changes include: Collections update - New Collection, List, Set and Map, Iterable and Iteratator as well as implementations including Hashtable and Vector. Most of the work is too support generics String - New StringBuilder and CharSequence as well as a Stirng formatter. The javac compiler  now uses the the StringBuilder instead of String Buffer. Since StringBuilder is synchronized there is a performance increase which has necessitated the wahat String constructor works. Comparable interface - The comparable interface works with Collections, making it easier to reuse. Try with resources - Closeable and AutoCloseable Annotations - While support for Annotations is provided it will only be a compile time support. SuppressWarnings, Deprecated, Override NIO - There is a subset of NIO Buffer that have been in use on the of the graphics packages and needs to be pulled in and also support for NIO File IO subset. Platform extensibility via Service Providers (ServiceLoader) - ServiceLoader interface dos late bindings of interface to existing implementations. It helpe to package an interface and behavior of the implementation at a later point in time.Provider classes must have a zero-argument constructor so that they can be instantiated during loading. They are located and instantiated on demand and are identified via a provider-configuration file in the METAINF/services resource directory. This is a mechansim from Java SE. import com.XYZ.ServiceA; ServiceLoader<ServiceA> sl1= new ServiceLoader(ServiceA.class); Resources: META-INF/services/com.XYZ.ServiceA: ServiceAProvider1 ServiceAProvider2 ServiceAProvider3 META-INF/services/ServiceB: ServiceBProvider1 ServiceBProvider2 From JSR - I would rather use this list I think The Generic Connection Framework (GCF) was previously specified in a number of different JSRs including CLDC, MIDP, CDC 1.2, and JSR 197. JSR 360 represents a rare opportunity to consolidated and reintegrate parts that were duplicated in other specifications into a single specification, upgrade the APIs as well provide new functionality. The proposal is to specify a combined GCF specification that can be used with Java ME or Java SE and be backwards compatible with previous implementations. Because of size limitations as well as the complexity of the some features like InvokeDynamic and Unicode 6 will not be included. Additionally, any language or library changes in JDK 8 will be not be included. On the upside, with all the changes being made, backwards compatibility will still be maintained. JSR 360 is a major step forward for Java ME in terms of platform modernization, language alignment, and embedded support. If you're interested in following the progress of this JSR see the JSR's java.net project for details of the email lists, discussions groups.

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• CodePlex Daily Summary for Sunday, August 26, 2012

  CodePlex Daily Summary for Sunday, August 26, 2012Popular ReleasesPhysics Helper XAML: Physics Helper XAML 1.1.0.0: This release supports creation of 2D Physics apps for Windows 8 RTM, Windows Phone 7.1 development, and Silverlight 5. It includes source code and samples in three separate solutions.TouchInjector: TouchInjector 1.0: Version 1.0BlackJumboDog: Ver5.7.1: 2012.08.25 Ver5.7.1 (1)?????·?????LING?????????????? (2)SMTP???（????）????、?????\?????????????????????Peulot Heshbon: Peulot Heshbon version 3.0.0: Available quizzes:Plus for Natural, Real and fragments Minus for Natural, Real and fragments Multiplication for Natural, Real and fragments Divide for Natural, Real and fragments Random for Natural, Real and fragments Compare 2 percentages Compare 2 fragments (Just for easy difficulty) Check if a number can be divided with another number exactly. Available Languages:Hebrew English Russian What's NewAdded new quiz: Compare 2 fragments. It is available only if you are in Eas...Visual Studio Team Foundation Server Branching and Merging Guide: v2 - Visual Studio 2012: Welcome to the Branching and Merging Guide Quality-Bar Details Documentation has been reviewed by Visual Studio ALM Rangers Documentation has been through an independent technical review Documentation has been reviewed by the quality and recording team All critical bugs have been resolved Known Issues / Bugs Spelling, grammar and content revisions are in progress. Hotfix will be published.Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.62: Fix for issue #18525 - escaped characters in CSS identifiers get double-escaped if the character immediately after the backslash is not normally allowed in an identifier. fixed symbol problem with nuget package. 4.62 should have nuget symbols available again.nopCommerce. Open source shopping cart (ASP.NET MVC): nopcommerce 2.65: As some of you may know we were planning to release version 2.70 much later (the end of September). But today we have to release this intermediate version (2.65). It fixes a critical issue caused by a third-party assembly when running nopCommerce on a server with .NET 4.5 installed. No major features have been introduced with this release as our development efforts were focused on further enhancements and fixing bugs. To see the full list of fixes and changes please visit the release notes p...MyRouter (Virtual WiFi Router): MyRouter 1.2.9: . Fix: Some missing changes for fixing the window subclassing crash. · Fix: fixed bug when Run MyRouter at the first Time. · Fix: Log File · Fix: improve performance speed application · fix: solve some Exception.eel Browser: eel 1.1.0.41 beta: Improved UI New features Bug fixesDynamics CRM 2011 Dummy Entity: First Release: This has been tested on CRM 2011 RU8 On-Premise IFD. Known Issue: The Test Dummy CRM page load event may throw an exception loading the first time as the iframe may not have finished loading. I have not been able to get the iframe OnReadyStateChange event to fire. But it is only a sample anyway. The zip file contains: Dummy Entity Visual studio solution. Test Dummy Visual Studio solution. Dummy Entity CRM Solution Test Dummy CRM Solution Installation: Unzip and import the CRM Solutions...Private cloud DMS: Essential server-client full package: Requirements: - SQL server >= 2008 (minimal Express - for Essential recommended) - .NET 4.0 (Server) - .NET 4.0 Client profile (Client) This version allow: - full file system functionality Restrictions: - Maximum 2 parallel users - No share spaces - No hosted business groups - No digital sign functionality - No ActiveDirectory connector - No Performance cache - No workflow - No messagingJavaScript Prototype Extensions: Release 1.1.0.0: Release 1.1.0.0 Add prototype extension for object. Add prototype extension for array.Glyphx: Version 1.2: This release includes the SdlDotNet.dll dependency in the setup, which you will need.TFS Project Test Migrator: TestPlanMigration v1.0.0: Release 1.0.0 This first version do not create the test cases in the target project because the goal was to restore a Test Plan + Test Suite hierarchy after a manual user deletion without restoring all the Project Collection Database. As I discovered, deleting a Test Plan will do the following : - Delete all TestSuiteEntry (the link between a Test Suite node and a Test Case) - Delete all TestSuite (the nodes in the test hierarchy), including root TestSuite - Delete the TestPlan Test c...ERPStore eCommerce FrontOffice: ERPStore.Core V4.0.0.2 MVC4 RTM: ERPStore.Core V4.0.0.2 MVC4 RTM (Code Source)ZXing.Net: ZXing.Net 0.8.0.0: sync with rev. 2393 of the java version improved API, direct support for multiple barcode decoding, wrapper for barcode generating many other improvements and fixes encoder and decoder command line clients demo client for emguCV dev documentation startedScintillaNET: ScintillaNET 2.5.1: This release has been built from the 2.5 branch. Issues closed: Issue # Title 32524 32524 32550 32550 32552 32552 25148 25148 32449 32449 32551 32551 32711 32711 MFCMAPI: August 2012 Release: Build: 15.0.0.1035 Full release notes at SGriffin's blog. If you just want to run the MFCMAPI or MrMAPI, get the executables. If you want to debug them, get the symbol files and the source. The 64 bit builds will only work on a machine with Outlook 2010 64 bit installed. All other machines should use the 32 bit builds, regardless of the operating system. Facebook BadgeDocument.Editor: 2013.2: Whats new for Document.Editor 2013.2: New save as Html document Improved Traslate support Minor Bug Fix's, improvements and speed upsPulse: Pulse Beta 5: Whats new in this release? Well to start with we now have Wallbase.cc Authentication! so you can access favorites or NSFW. This version requires .NET 4.0, you probably already have it, but if you don't it's a free and easy download from Microsoft. Pulse can bet set to start on Windows startup now too. The Wallpaper setter has settings now, so you can change the background color of the desktop and the Picture Position (Tile/Center/Fill/etc...) I've switched to Windows Forms instead of WPF...New Projects508 Compliance Validator: This tool checks aspx and ascx pages against 508 Accessibilty guidelines and also allows you to add your own rules.BF for WP: BF for WP is a visual Brainfuck interpter for Windows Phone.Climate Control: App lets you vote on whether you're too hot or too cold so the dummy next to the air con controls can adjust the thermostat.Custom Captcha Plugin for Kooboo CMS for adding content or sending feedback: Custom Captcha Plugin for Kooboo CMS for adding content or sending feedbackGalleryDownloader: This project takes aim on downloading free photogalleries through the Internet. Highly Maintainable Web Services: The Highly Maintainable Web Services project is a reference architecture application for .NET that demonstrates how to build highly maintainable web services.Its.Validation: A C# DSL for writing rules in a composable, functional style.Kaku by wifi: The projects purpose: Make your phone a part of your house hold by being able to control certail elektric devices with your phone such as, light, electric curtaLogin with Google in ASP.Net MVC3 & Get data from Google User: ASP.Net developer can use this code: asp.net mvc3 web project which contains login with google and pull data from user's google accountMabiCommerce: MabiCommerce is an advanced Commerce Calculator for the MMORPG Mabinogi.Mapture the FLAG: A location based game for wp7mn: sumSharePoint 2010: SharePoint 2010 utilitiesSHIORI.NET: ???SHIORI????????????????????Temp and Stress: Tieni sotto controllo le temperature della tua CPU e effettua Stress Test e Benchmark!VisiblityControl – An Alternative to Converters: A templated content control hosting to remove the pain of using the BooleanToVisibilityConverter. The property IsTrue determines what is shown.Whatsnexx Integration for Orchard CMS: Orchard Whatsnexx makes it easier for Orchard users to send an event to the Whatsnexx Ticket Bus service API, of the Whatsnexx GatewayWINRT \ Metro Store \ open marketing solution: This project is aimed at creating a public shopping cart, that is available to all windows 8 users free. products are screened added by administrators

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• Project Jigsaw: Late for the train: The Q&A

  - by Mark Reinhold

  I recently proposed, to the Java community in general and to the SE 8 (JSR 337) Expert Group in particular, to defer Project Jigsaw from Java 8 to Java 9. I also proposed to aim explicitly for a regular two-year release cycle going forward. Herewith a summary of the key questions I’ve seen in reaction to these proposals, along with answers. Making the decision Q Has the Java SE 8 Expert Group decided whether to defer the addition of a module system and the modularization of the Platform to Java SE 9? A No, it has not yet decided. Q By when do you expect the EG to make this decision? A In the next month or so. Q How can I make sure my voice is heard? A The EG will consider all relevant input from the wider community. If you have a prominent blog, column, or other communication channel then there’s a good chance that we’ve already seen your opinion. If not, you’re welcome to send it to the Java SE 8 Comments List, which is the EG’s official feedback channel. Q What’s the overall tone of the feedback you’ve received? A The feedback has been about evenly divided as to whether Java 8 should be delayed for Jigsaw, Jigsaw should be deferred to Java 9, or some other, usually less-realistic, option should be taken. Project Jigsaw Q Why is Project Jigsaw taking so long? A Project Jigsaw started at Sun, way back in August 2008. Like many efforts during the final years of Sun, it was not well staffed. Jigsaw initially ran on a shoestring, with just a handful of mostly part-time engineers, so progress was slow. During the integration of Sun into Oracle all work on Jigsaw was halted for a time, but it was eventually resumed after a thorough consideration of the alternatives. Project Jigsaw was really only fully staffed about a year ago, around the time that Java 7 shipped. We’ve added a few more engineers to the team since then, but that can’t make up for the inadequate initial staffing and the time lost during the transition. Q So it’s really just a matter of staffing limitations and corporate-integration distractions? A Aside from these difficulties, the other main factor in the duration of the project is the sheer technical difficulty of modularizing the JDK. Q Why is modularizing the JDK so hard? A There are two main reasons. The first is that the JDK code base is deeply interconnected at both the API and the implementation levels, having been built over many years primarily in the style of a monolithic software system. We’ve spent considerable effort eliminating or at least simplifying as many API and implementation dependences as possible, so that both the Platform and its implementations can be presented as a coherent set of interdependent modules, but some particularly thorny cases remain. Q What’s the second reason? A We want to maintain as much compatibility with prior releases as possible, most especially for existing classpath-based applications but also, to the extent feasible, for applications composed of modules. Q Is modularizing the JDK even necessary? Can’t you just put it in one big module? A Modularizing the JDK, and more specifically modularizing the Java SE Platform, will enable standard yet flexible Java runtime configurations scaling from large servers down to small embedded devices. In the long term it will enable the convergence of Java SE with the higher-end Java ME Platforms. Q Is Project Jigsaw just about modularizing the JDK? A As originally conceived, Project Jigsaw was indeed focused primarily upon modularizing the JDK. The growing demand for a truly standard module system for the Java Platform, which could be used not just for the Platform itself but also for libraries and applications built on top of it, later motivated expanding the scope of the effort. Q As a developer, why should I care about Project Jigsaw? A The introduction of a modular Java Platform will, in the long term, fundamentally change the way that Java implementations, libraries, frameworks, tools, and applications are designed, built, and deployed. Q How much progress has Project Jigsaw made? A We’ve actually made a lot of progress. Much of the core functionality of the module system has been prototyped and works at both compile time and run time. We’ve extended the Java programming language with module declarations, worked out a structure for modular source trees and corresponding compiled-class trees, and implemented these features in javac. We’ve defined an efficient module-file format, extended the JVM to bootstrap a modular JRE, and designed and implemented a preliminary API. We’ve used the module system to make a good first cut at dividing the JDK and the Java SE API into a coherent set of modules. Among other things, we’re currently working to retrofit the java.util.ServiceLoader API to support modular services. Q I want to help! How can I get involved? A Check out the project page, read the draft requirements and design overview documents, download the latest prototype build, and play with it. You can tell us what you think, and follow the rest of our work in real time, on the jigsaw-dev list. The Java Platform Module System JSR Q What’s the relationship between Project Jigsaw and the eventual Java Platform Module System JSR? A At a high level, Project Jigsaw has two phases. In the first phase we’re exploring an approach to modularity that’s markedly different from that of existing Java modularity solutions. We’ve assumed that we can change the Java programming language, the virtual machine, and the APIs. Doing so enables a design which can strongly enforce module boundaries in all program phases, from compilation to deployment to execution. That, in turn, leads to better usability, diagnosability, security, and performance. The ultimate goal of the first phase is produce a working prototype which can inform the work of the Module-System JSR EG. Q What will happen in the second phase of Project Jigsaw? A The second phase will produce the reference implementation of the specification created by the Module-System JSR EG. The EG might ultimately choose an entirely different approach than the one we’re exploring now. If and when that happens then Project Jigsaw will change course as necessary, but either way I think that the end result will be better for having been informed by our current work. Maven & OSGi Q Why not just use Maven? A Maven is a software project management and comprehension tool. As such it can be seen as a kind of build-time module system but, by its nature, it does nothing to support modularity at run time. Q Why not just adopt OSGi? A OSGi is a rich dynamic component system which includes not just a module system but also a life-cycle model and a dynamic service registry. The latter two facilities are useful to some kinds of sophisticated applications, but I don’t think they’re of wide enough interest to be standardized as part of the Java SE Platform. Q Okay, then why not just adopt the module layer of OSGi? A The OSGi module layer is not operative at compile time; it only addresses modularity during packaging, deployment, and execution. As it stands, moreover, it’s useful for library and application modules but, since it’s built strictly on top of the Java SE Platform, it can’t be used to modularize the Platform itself. Q If Maven addresses modularity at build time, and the OSGi module layer addresses modularity during deployment and at run time, then why not just use the two together, as many developers already do? A The combination of Maven and OSGi is certainly very useful in practice today. These systems have, however, been built on top of the existing Java platform; they have not been able to change the platform itself. This means, among other things, that module boundaries are weakly enforced, if at all, which makes it difficult to diagnose configuration errors and impossible to run untrusted code securely. The prototype Jigsaw module system, by contrast, aims to define a platform-level solution which extends both the language and the JVM in order to enforce module boundaries strongly and uniformly in all program phases. Q If the EG chooses an approach like the one currently being taken in the Jigsaw prototype, will Maven and OSGi be made obsolete? A No, not at all! No matter what approach is taken, to ensure wide adoption it’s essential that the standard Java Platform Module System interact well with Maven. Applications that depend upon the sophisticated features of OSGi will no doubt continue to use OSGi, so it’s critical that implementations of OSGi be able to run on top of the Java module system and, if suitably modified, support OSGi bundles that depend upon Java modules. Ideas for how to do that are currently being explored in Project Penrose. Java 8 & Java 9 Q Without Jigsaw, won’t Java 8 be a pretty boring release? A No, far from it! It’s still slated to include the widely-anticipated Project Lambda (JSR 335), work on which has been going very well, along with the new Date/Time API (JSR 310), Type Annotations (JSR 308), and a set of smaller features already in progress. Q Won’t deferring Jigsaw to Java 9 delay the eventual convergence of the higher-end Java ME Platforms with Java SE? A It will slow that transition, but it will not stop it. To allow progress toward that convergence to be made with Java 8 I’ve suggested to the Java SE 8 EG that we consider specifying a small number of Profiles which would allow compact configurations of the SE Platform to be built and deployed. Q If Jigsaw is deferred to Java 9, would the Oracle engineers currently working on it be reassigned to other Java 8 features and then return to working on Jigsaw again after Java 8 ships? A No, these engineers would continue to work primarily on Jigsaw from now until Java 9 ships. Q Why not drop Lambda and finish Jigsaw instead? A Even if the engineers currently working on Lambda could instantly switch over to Jigsaw and immediately become productive—which of course they can’t—there are less than nine months remaining in the Java 8 schedule for work on major features. That’s just not enough time for the broad review, testing, and feedback which such a fundamental change to the Java Platform requires. Q Why not ship the module system in Java 8, and then modularize the platform in Java 9? A If we deliver a module system in one release but don’t use it to modularize the JDK until some later release then we run a big risk of getting something fundamentally wrong. If that happens then we’d have to fix it in the later release, and fixing fundamental design flaws after the fact almost always leads to a poor end result. Q Why not ship Jigsaw in an 8.5 release, less than two years after 8? Or why not just ship a new release every year, rather than every other year? A Many more developers work on the JDK today than a couple of years ago, both because Oracle has dramatically increased its own investment and because other organizations and individuals have joined the OpenJDK Community. Collectively we don’t, however, have the bandwidth required to ship and then provide long-term support for a big JDK release more frequently than about every other year. Q What’s the feedback been on the two-year release-cycle proposal? A For just about every comment that we should release more frequently, so that new features are available sooner, there’s been another asking for an even slower release cycle so that large teams of enterprise developers who ship mission-critical applications have a chance to migrate at a comfortable pace.

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• UIScrollView zoomToRect not zooming to given rect (created from UITouch CGPoint)

  - by pmhart

  My application has a UIScrollView with one subview. The subview is an extended UIView which prints a PDF page to itself using layers in the drawLayer event. Zooming using the built in pinching works great. setZoomScale also works as expected. I have been struggling with the zoomToRect function. I found an example online which makes a CGRect zoomRect variable from a given CGPoint. In the touchesEnded function, if there was a double tap and they are all the way zoomed out, I want to zoom in to that PDFUIView I created as though they were pinching out with the center of the pinch where they double tapped. So assume that I pass the UITouch variable to my function which utilizes zoomToRect if they double tap. I started with the following function I found on apples site: http://developer.apple.com/iphone/library/documentation/WindowsViews/Conceptual/UIScrollView_pg/ZoomZoom/ZoomZoom.html The following is a modified version for my UIScrollView extended class: - (void)zoomToCenter:(float)scale withCenter:(CGPoint)center { CGRect zoomRect; zoomRect.size.height = self.frame.size.height / scale; zoomRect.size.width = self.frame.size.width / scale; zoomRect.origin.x = center.x - (zoomRect.size.width / 2.0); zoomRect.origin.y = center.y - (zoomRect.size.height / 2.0); //return zoomRect; [self zoomToRect:zoomRect animated:YES]; } When I do this, the UIScrollView seems to zoom using the bottom right edge of the zoomRect above and not the center. If I make UIView like this UIView *v = [[UIView alloc] initWithFrame:zoomRect]; [v setBackgroundColor:[UIView redColor]]; [self addSubview:v]; The red box shows up with the touch point dead in the center. Please note: I am writing this from my PC, I recall messing around with the divided by two part on my Mac, so just assume that this draws a rect with the touch point in the center. If the UIView drew off center but zoomed to the right spot it would be all good. However, what happens is when it preforms the zoomToRect it seems to use the bottom right off the zoomRect at the top left of the zoomed in results. Also, I noticed that depending on where I click on the UIScrollView, it anchors to diffrent spots. It almost seems like there is a cross down the middle and it's reflecting the points somehow as though anywhere left of the middle is a negative reflection and anywhere right of the middle is a positive reflection? This seems to complicated, shouldn't it just zoom to the rect that was drawn as the UIView was able to draw? I used a lot of research to figure out how to create a PDF that scales in high quality, so I am assuming that using the CALayer may be throwing off the coordinate system? But to the UIScrollView it should just treat it as a view with 768x985 dimensions. This is sort of advanced, please assume the code for creating the zoomRect is all good. There is something deeper with the CALayer in the UIView which is in the UIScrollView....

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• To divide the big text into columns.

  - by kalininew

  Problem: There is a big piece of the text: <div class="cont"> <p> Sed ut perspiciatis, unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam eaque ipsa, quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt, explicabo. Nemo enim ipsam voluptatem, quia voluptas sit, aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos, qui ratione voluptatem sequi nesciunt, neque porro quisquam est, qui dolorem ipsum, quia dolor sit, amet, </p> <p> consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt, ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit, qui in ea voluptate velit esse, quam nihil molestiae consequatur, vel illum, qui dolorem eum fugiat, quo voluptas nulla pariatur? At vero eos et </p> <p> accusamus et iusto odio dignissimos ducimus, qui blanditiis praesentium voluptatum deleniti atque corrupti, quos dolores et quas molestias excepturi sint, obcaecati cupiditate non provident, similique sunt in culpa, qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio, cumque nihil impedit, quo minus id, quod maxime placeat, </p> <p> facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Temporibus autem quibusdam et aut officiis debitis aut rerum necessitatibus saepe eveniet, ut et voluptates repudiandae sint et molestiae non recusandae. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat. </p> <p> Sed ut perspiciatis, unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam eaque ipsa, quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt, explicabo. Nemo enim ipsam voluptatem, quia voluptas sit, aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos, qui ratione voluptatem sequi nesciunt, neque porro quisquam est, qui dolorem ipsum, quia dolor sit, amet, </p> <p> consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt, ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit, qui in ea voluptate velit esse, quam nihil molestiae consequatur, vel illum, qui dolorem eum fugiat, quo voluptas nulla pariatur? At vero eos et </p> <p> accusamus et iusto odio dignissimos ducimus, qui blanditiis praesentium voluptatum deleniti atque corrupti, quos dolores et quas molestias excepturi sint, obcaecati cupiditate non provident, similique sunt in culpa, qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio, cumque nihil impedit, quo minus id, quod maxime placeat, </p> <p> facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Temporibus autem quibusdam et aut officiis debitis aut rerum necessitatibus saepe eveniet, ut et voluptates repudiandae sint et molestiae non recusandae. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat. </p> </div> It is necessary: To divide it on two columns. On page it should be divided on two about identical (on height) columns. If it is possible: at change of the sizes of the container of the text, a column should remain identical height. Whether probably to set number "n" - on how many columns to divide the big piece of the text. That is to divide the text into any number of columns. Is available: php, xslt, css, pure javascript (without jQuey). What tool is better for using? As it to make, that the decision was ?ross browser compatible.

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• Implementing a popularity algorithm in Django

  - by TheLizardKing

  I am creating a site similar to reddit and hacker news that has a database of links and votes. I am implementing hacker news' popularity algorithm and things are going pretty swimmingly until it comes to actually gathering up these links and displaying them. The algorithm is simple: Y Combinator's Hacker News: Popularity = (p - 1) / (t + 2)^1.5` Votes divided by age factor. Where` p : votes (points) from users. t : time since submission in hours. p is subtracted by 1 to negate submitter's vote. Age factor is (time since submission in hours plus two) to the power of 1.5.factor is (time since submission in hours plus two) to the power of 1.5. I asked a very similar question over yonder http://stackoverflow.com/questions/1964395/complex-ordering-in-django but instead of contemplating my options I choose one and tried to make it work because that's how I did it with PHP/MySQL but I now know Django does things a lot differently. My models look something (exactly) like this class Link(models.Model): category = models.ForeignKey(Category) user = models.ForeignKey(User) created = models.DateTimeField(auto_now_add = True) modified = models.DateTimeField(auto_now = True) fame = models.PositiveIntegerField(default = 1) title = models.CharField(max_length = 256) url = models.URLField(max_length = 2048) def __unicode__(self): return self.title class Vote(models.Model): link = models.ForeignKey(Link) user = models.ForeignKey(User) created = models.DateTimeField(auto_now_add = True) modified = models.DateTimeField(auto_now = True) karma_delta = models.SmallIntegerField() def __unicode__(self): return str(self.karma_delta) and my view: def index(request): popular_links = Link.objects.select_related().annotate(karma_total = Sum('vote__karma_delta')) return render_to_response('links/index.html', {'links': popular_links}) Now from my previous question, I am trying to implement the algorithm using the sorting function. An answer from that question seems to think I should put the algorithm in the select and sort then. I am going to paginate these results so I don't think I can do the sorting in python without grabbing everything. Any suggestions on how I could efficiently do this? EDIT This isn't working yet but I think it's a step in the right direction: from django.shortcuts import render_to_response from linkett.apps.links.models import * def index(request): popular_links = Link.objects.select_related() popular_links = popular_links.extra( select = { 'karma_total': 'SUM(vote.karma_delta)', 'popularity': '(karma_total - 1) / POW(2, 1.5)', }, order_by = ['-popularity'] ) return render_to_response('links/index.html', {'links': popular_links}) This errors out into: Caught an exception while rendering: column "karma_total" does not exist LINE 1: SELECT ((karma_total - 1) / POW(2, 1.5)) AS "popularity", (S... EDIT 2 Better error? TemplateSyntaxError: Caught an exception while rendering: missing FROM-clause entry for table "vote" LINE 1: SELECT ((vote.karma_total - 1) / POW(2, 1.5)) AS "popularity... My index.html is simply: {% block content %} {% for link in links %} karma-up {{ link.karma_total }} karma-down {{ link.title }} Posted by {{ link.user }} to {{ link.category }} at {{ link.created }} {% empty %} No Links {% endfor %} {% endblock content %} EDIT 3 So very close! Again, all these answers are great but I am concentrating on a particular one because I feel it works best for my situation. from django.db.models import Sum from django.shortcuts import render_to_response from linkett.apps.links.models import * def index(request): popular_links = Link.objects.select_related().extra( select = { 'popularity': '(SUM(links_vote.karma_delta) - 1) / POW(2, 1.5)', }, tables = ['links_link', 'links_vote'], order_by = ['-popularity'], ) return render_to_response('links/test.html', {'links': popular_links}) Running this I am presented with an error hating on my lack of group by values. Specifically: TemplateSyntaxError at / Caught an exception while rendering: column "links_link.id" must appear in the GROUP BY clause or be used in an aggregate function LINE 1: ...karma_delta) - 1) / POW(2, 1.5)) AS "popularity", "links_lin... Not sure why my links_link.id wouldn't be in my group by but I am not sure how to alter my group by, django usually does that.

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• Best way to get back to using the power of lxml after having to use a regex to find something in an

  - by PyNEwbie

  I am trying to rip some text out of a large number of html documents (numbers in the hundreds of thousands). The documents are really forms but they are prepared by a very large group of different organizations so there is significant variation in how they create the document. For example, the documents are divided into chapters. I might want to extract the contents of Chapter 5 from every document so I can analyze the content of the chapter. Initially I thought this would be easy but it turns out that the authors might use a set of non-nested tables throughout the document to hold the content so that Chapter n could be displayed using td tags inside a table. Or they might use other elements such as p tags H tags, div tags or any other block level element. After trying repeatedly to use lxml to help me identify the beginning and end of each chapter I have determined that it is a lot cleaner to use a regular expression because in every case, no matter what the enclosing html element is the chapter label is always in the form of >Chapter # It is a little more complicated in that there might be some white space or non-breaking space represented in different ways (  or   or just spaces). Nonetheless it was trivial to write a regular expression to identify the beginning of each section. (The beginning of one section is the end of the previous section.) But now I want to use lxml to get the text out. My thought is that I have really no choice but to walk along my string to find the close tag for the element that encloses the text I am using to find the relevant section. That is here is one example where the element holding the Chapter name is a div <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Chapter 1.&#160;&#160;&#160;Our Beginnings.</font></div> So I am imagining that I would begin at the location where I found the match for chapter 1 and set up a regular expressions to find the next </div|</td|</p|</h1 . . . So at this point I have identified the type of element holding my chapter heading I can use the same logic to find all of the text that is within that element that is set up a regular expression to help me mark from >Chapter 1.&#160;&#160;&#160;Our Beginnings.< So I have identified where my Chapter 1 begins I can do the same for chapter 2 (which is where Chapter 1 ends) Now I am imagining that I am going to snip the document beginning at the opening of the element that I identified as the element the indicates where chapter 1 begins and ending just before the opening of the element that I identified as the element that indicates where Chapter 2 begins. The string that I have identified will then be fed to lxml to use its power to get the content. I am going to all of this trouble because I have read over and over - never use a regular expression to extract content from html documents and I have not hit on a way to be as accurate with lxml to identify the starting and ending locations for the text I want to extract. For example, I can never be certain that the subtitle of Chapter 1 is Our Beginnings it could be Our Red Canary. Let me say that I spent two solid days trying with lxml to be confident that I had the beginning and ending elements and I could only be accurate <60% of the time but a very short regular expression has given me better than 95% success. I have a tendency to make things more complicated than necessary so I am wondering if anyone has seen or solved a similar problems and if they had an approach (not the details mind you) that they would like to offer.

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• Data munging and data import scripting

  - by morpheous

  I need to write some scripts to carry out some tasks on my server (running Ubuntu server 8.04 TLS). The tasks are to be run periodically, so I will be running the scripts as cron jobs. I have divided the tasks into "group A" and "group B" - because (in my mind at least), they are a bit different. Task Group A import data from a file and possibly reformat it - by reformatting, I mean doing things like santizing the data, possibly normalizing it and or running calculations on 'columns' of the data Import the munged data into a database. For now, I am mostly using mySQL for the vast majority of imports - although some files will be imported into a sqlLite database. Note: The files will be mostly text files, although some of the files are in a binary format (my own proprietary format, written by a C++ application I developed). Task Group B Extract data from the database Perform calculations on the data and either insert or update tables in the database. My coding experience is is primarily as a C/C++ developer, although I have been using PHP as well for the last 2 years or so. I am from a windows background so I am still finding my feet in the linux environment. My question is this - I need to write scripts to perform the tasks I described above. Although I suppose I could write a few C++ applications to be used in the shell scripts, I think it may be better to write them in a scripting language (maybe this is a flawed assumption?). My thinking is that it would be easier to modify thins in a script - no need to rebuild etc for changes to functionality. Additionally, C++ data munging in C++ tends to involve more lines of code than "natural" scripting languages such as Perl, Python etc. Assuming that the majority of people on here agree that scripting is the way to go, herein lies my dilema. Which scripting language to use to perform the tasks above (giving my background). My gut instinct tells me that Perl (shudder) would be the most obvious choice for performing all of the above tasks. BUT (and that is a big BUT). The mere mention of Perl makes my toes curl, as I had a very, very bag experience with it a while back. The syntax seems quite unnatural to me - despite how many times I have tried to learn it - so if possible, I would really like to give it a miss. PHP (which I already know), also am not sure is a good candidate for scripting on the CLI (I have not seen many examples on how to do this etc - so I may be wrong). The last thing I must mention is that IF I have to learn a new language in order to do this, I cannot afford (time constraint) to spend more than a day, in learning the key commands/features required in order to do this (I can always learn the details of the language later, once I have actually deployed the scripts). So, which scripting language would you recommend (PHP, Python, Perl, [insert your favorite here]) - and most importantly WHY?. Or, should I just stick to writing little C++ applications that I call in a shell script?. Lastly, if you have suggested a scripting language, can you please show with a FEW lines (Perl mongers - I'm looking in your direction [nothing to cryptic!] ;) ) how I can use the language you suggested to do what I want to do. Hopefully, the lines you present will convince me that it can be done easily and elegantly in the language you suggested.

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• LinkedList Wrong Display(string builder)

  - by Chris

  Hello, The following program is a basic linked list divided in 3 classes. In the tester class (main) i add several numbers to the list (sorted). But insteed of getting the numbers as a result i get the result: LinkedList.LinkedList Is something wrong with the stringbuilder (the program was first in java where a string buffer was used, but that should be the same i think?) LinkedListTester.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace LinkedList { public class LinkedListTester { static void Main(string[] args) { LinkedList ll = new LinkedList(); ll.addDataSorted(5); ll.addDataSorted(7); ll.addDataSorted(13); ll.addDataSorted(1); ll.addDataSorted(17); ll.addDataSorted(8); Console.WriteLine(ll); } } }/LinkedList/ LinkedList.cs using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace LinkedList { public class LinkedList { //toestand private LinkedListNode first; private LinkedListNode last; //gedrag public LinkedList() { first = null; last = null; } public void addDataInFront(int data) { first = new LinkedListNode(data, first); if (last == null){ last = first; } }/*addDataInFront*/ public void addDataToBack(int data) { if (first == null) { addDataInFront(data); } else { last.setNext(new LinkedListNode(data, null)); last = last.getNext(); } }/*addDataToBack*/ public void addDataSorted(int data) { if (first == null || first.getData() > data) { addDataInFront(data); } else { LinkedListNode currentNode = first; while (currentNode.getNext() != null && currentNode.getNext().getData() < data) { currentNode = currentNode.getNext(); } currentNode.setNext(new LinkedListNode(data, currentNode.getNext())); currentNode = currentNode.getNext(); if (currentNode.getNext() == null) { last = currentNode; } } }/*addDataSorted*/ public String toString() { StringBuilder Buf = new StringBuilder(); LinkedListNode currentNode = first; while (currentNode != null) { Buf.Append(currentNode.getData()); Buf.Append(' '); currentNode = currentNode.getNext(); } return Buf.ToString(); }/*toString*/ }/*LinkedList*/ }/LinkedList/ LinkedListNode: using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace LinkedList { public class LinkedListNode { //toestand private int data; private LinkedListNode next; private LinkedListNode previous; //gedrag public LinkedListNode(int data, LinkedListNode next) { this.data = data; this.next = next; this.previous = null; } public LinkedListNode(int data, LinkedListNode next, LinkedListNode previous) { this.data = data; this.next = next; this.previous = previous; } public LinkedListNode getNext() { return next; } public LinkedListNode getPrevious() { return previous; } public void setNext(LinkedListNode next) { this.next = next; } public void setPrevious(LinkedListNode previous) { this.previous = previous; } public int getData() { return data; } }/*LinkedListNode*/ }/LinkedList/

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• Agile: User Stories for Machine Learning Project?

  - by benjismith

  I've just finished up with a prototype implementation of a supervised learning algorithm, automatically assigning categorical tags to all the items in our company database (roughly 5 million items). The results look good, and I've been given the go-ahead to plan the production implementation project. I've done this kind of work before, so I know how the functional components of the software. I need a collection of web crawlers to fetch data. I need to extract features from the crawled documents. Those documents need to be segregated into a "training set" and a "classification set", and feature-vectors need to be extracted from each document. Those feature vectors are self-organized into clusters, and the clusters are passed through a series of rebalancing operations. Etc etc etc etc. So I put together a plan, with about 30 unique development/deployment tasks, each with time estimates. The first stage of development -- ignoring some advanced features that we'd like to have in the long-term, but aren't high enough priority to make it into the development schedule yet -- is slated for about two months worth of work. (Keep in mind that I already have a working prototype, so the final implementation is significantly simpler than if the project was starting from scratch.) My manager said the plan looked good to him, but he asked if I could reorganize the tasks into user stories, for a few reasons: (1) our project management software is totally organized around user stories; (2) all of our scheduling is based on fitting entire user stories into sprints, rather than individually scheduling tasks; (3) other teams -- like the web developers -- have made great use of agile methodologies, and they've benefited from modelling all the software features as user stories. So I created a user story at the top level of the project: As a user of the system, I want to search for items by category, so that I can easily find the most relevant items within a huge, complex database. Or maybe a better top-level story for this feature would be: As a content editor, I want to automatically create categorical designations for the items in our database, so that customers can easily find high-value data within our huge, complex database. But that's not the real problem. The tricky part, for me, is figuring out how to create subordinate user stories for the rest of the machine learning architecture. Case in point... I know that the algorithm requires two major architectural subdivisions: (A) training, and (B) classification. And I know that the training portion of the architecture requires construction of a cluster-space. All the Agile Development literature I've read seems to indicate that a user story should be the "smallest possible implementation that provides any business value". And that makes a lot of sense when designing a piece of end-user software. Start small, and then incrementally add value when users demand additional functionality. But a cluster-space, in and of itself, provides zero business value. Nor does a crawler, or a feature-extractor. There's no business value (not for the end-user, or for any of the roles internal to the company) in a partial system. A trained cluster-space is only possible with the crawler and feature extractor, and only relevant if we also develop an accompanying classifier. I suppose it would be possible to create user stories where the subordinate components of the system act as the users in the stories: As a supervised-learning cluster-space construction routine, I want to consume data from a feature extractor, so that I can exist. But that seems really weird. What benefit does it provide me as the developer (or our users, or any other stakeholders, for that matter) to model my user stories like that? Although the main story can be easily divided along architectural-component boundaries (crawler, trainer, classifier, etc), I can't think of any useful decomposition from a user's perspective. What do you guys think? How do you plan Agile user stories for sophisticated, indivisible, non-user-facing components?

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• Android - determine specific locations (X,Y coordinates) on a Bitmap on different resolutions?

  - by Mike

  My app that I am trying to create is a board game. It will have one bitmap as the board and pieces that will move to different locations on the board. The general design of the board is square, has a certain number of columns and rows and has a border for looks. Think of a chess board or scrabble board. Before using bitmaps, I first created the board and boarder by manually drawing it - drawLine & drawRect. I decided how many pixels in width the border would be based on the screen width and height passed in on "onSizeChanged". The remaining screen I divided by the number of columns or rows I needed. For examples sake, let's say the screen dimensions are 102 x 102. I may have chosen to set the border at 1 and set the number of rows & columns at 10. That would leave 100 x 100 left (reduced by two to account for the top & bottom border, as well as left/right border). Then with columns and rows set to 10, that would leave 10 pixels left for both height and width. No matter what screen size is passed in, I store exactly how many pixels in width the boarder is and the height & width of each square on the board. I know exactly what location on the screen to move the pieces to based on a simple formula and I know exactly what cell a user touched to make a move. Now how does that work with bitmaps? Meaning, if I create 3 different background bitmaps, once for each density, won't they still be resized to fit each devices screen resolution, because from what I read there were not just 3 screen resolutions, but 5 and now with tablets - even more. If I or Android scales the bitmaps up or down to fit the current devices screen size, how will I know how wide the border is scaled to and the dimensions of each square in order to figure out where to move a piece or calculate where a player touched. So far the examples I have looked at just show how to scale the overall bitmap and get the overall bitmaps width and height. But, I don't see how to tell how many pixels wide or tall each part of the board would be after it was scaled. When I draw each line and rectangle myself based in the screen dimensions from onSizeChanged, I always know these dimensions. If anyone has any sample code or a URL to point me to that I can a read about this with bitmaps, I would appreciate it. Thanks, --Mike BTW, here is some sample code (very simplified) on how I know the dimensions of my game board (border and squares) no matter the screen size. Now I just need to know how to do this with the board as a bitmap that gets scaled to any screen size. @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { intScreenWidth = w; intScreenHeight = h; // Set Border width - my real code changes this value based on the dimensions of w // and h that are passed in. In other words bigger screens get a slightly larger // border. intOuterBorder = 1; /** Reserve part of the board for the boardgame and part for player controls & score My real code forces this to be square, but this is good enough to get the point across. **/ floatBoardHeight = intScreenHeight / 4 * 3; // My real code actually causes floatCellWidth and floatCellHeight to // be equal (Square). floatCellWidth = (intScreenWidth - intOuterBorder * 2 ) / intNumColumns; floatCellHeight = (floatBoardHeight - intOuterBorder * 2) / intNumRows; super.onSizeChanged(w, h, oldw, oldh); }

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• What is the best free or low-cost Java reporting library (e.g. BIRT, JasperReports, etc.) for making

  - by Max3000

  I want to print, email and write to PDF very simple reports. The reports are basically a list of items, divided in various sections/columns. The sections are not necessarily identical. Think newspaper. I just wasted a solid 2 days of work trying to make this kind of reports using JasperReports. I find that Jasper is great for outputing "normalized" data. The kind that would come out of a database for instance, each row neatly describing an item and each item printed on a line. I'm simplifying a bit but that's the idea. However, given what I want to do I always ended up completely lost. Data not being displayed for no apparent reason, columns of texts never the correct size, column positioning always ending up incorrect, pagination not sanely possible (I was never able to figure it out; the FAQ gives an obscure workaround), etc. I came to the conclusion that Jasper is really not built to make the kind of reports I want. Am I missing something? I'm ready to pay for a tool, as long as the price is reasonable. By reasonable I mean a few $100s. Thanks. EDIT: To answer cetus, here is more information about the report I made in Jasper. What I want is something like this: text text text text ------------------- text | text text |---------- text | text text | text --------| text text |---------- text | text What I made in jasper is this: (detail band) subreport | subreport ------------------------------------ subreport | subreport ------------------------------------ subreport | subreport The subreports are all the same actual report. This report has one field (called "field") and basically just prints this field in a detail band. Hence, running a single subreport simply lists all items from the datasource. The datasource itself is a simple custom JRDatasource containing a collection of strings in the field "field". The datasource iterates over the collection until there are no more strings. Each subreport has its own datasource. I tried many different variations of the above, with all sorts of different properties for the report, subreports, etc. IMO, this is fairly simple stuff. However, the problems I encounter are as follows: Subreports starting from the 3rd don't show up when their position type is 'float'. They do show up when they have 'fix relative to top'. However, I don't want to do this because the first two subreports can be of any length. I can't make each subreport to stretch according to its own length. Instead, they either don't stretch at all (which is not desirable because they have different lenghts) or they stretch according to the longest subreport. This makes a weird layout for sure. Pagination doesn't happen. If some subreports fall outside the page, they simple don't show. One alternative is to increase the 'page height' considerably and the 'detail band height' accordingly. However, in this case it is not really possibly to know the total height in advance. So I'm stuck with calculating/guessing it myself, before the report is even generated. More importantly, long reports end up on one page and this is not acceptable (the printout text is too small, it's ugly/non-professional to have different reports with different PDF page lengths, etc.). BTW, I used iReport so it's possibly limitations of iReport I'm listing here and not of Jasper itself. That's one of the things I'm trying to find out asking this question here. One alternative would be to generate the jrxml myself with just static text but I'm afraid I'll encounter the very same limitations. Anyway, I just generally wasted so much time getting anything done with Jasper that I can't help thinking its not the right tool for the job. (Not to say that Jasper doesn't excel in what it's good at).

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• Guide to reduce TFS database growth using the Test Attachment Cleaner

  - by terje

  Recently there has been several reports on TFS databases growing too fast and growing too big.  Notable this has been observed when one has started to use more features of the Testing system.  Also, the TFS 2010 handles test results differently from TFS 2008, and this leads to more data stored in the TFS databases. As a consequence of this there has been released some tools to remove unneeded data in the database, and also some fixes to correct for bugs which has been found and corrected during this process.  Further some preventive practices and maintenance rules should be adopted. A lot of people have blogged about this, among these are: Anu’s very important blog post here describes both the problem and solutions to handle it.  She describes both the Test Attachment Cleaner tool, and also some QFE/CU releases to fix some underlying bugs which prevented the tool from being fully effective. Brian Harry’s blog post here describes the problem too This forum thread describes the problem with some solution hints. Ravi Shanker’s blog post here describes best practices on solving this (TBP) Grant Holidays blogpost here describes strategies to use the Test Attachment Cleaner both to detect space problems and how to rectify them.   The problem can be divided into the following areas: Publishing of test results from builds Publishing of manual test results and their attachments in particular Publishing of deployment binaries for use during a test run Bugs in SQL server preventing total cleanup of data (All the published data above is published into the TFS database as attachments.) The test results will include all data being collected during the run.  Some of this data can grow rather large, like IntelliTrace logs and video recordings.   Also the pushing of binaries which happen for automated test runs, including tests run during a build using code coverage which will include all the files in the deployment folder, contributes a lot to the size of the attached data.   In order to handle this systematically, I have set up a 3-stage process: Find out if you have a database space issue Set up your TFS server to minimize potential database issues If you have the “problem”, clean up the database and otherwise keep it clean   Analyze the data Are your database( s) growing ?  Are unused test results growing out of proportion ? To find out about this you need to query your TFS database for some of the information, and use the Test Attachment Cleaner (TAC) to obtain some  more detailed information. If you don’t have too many databases you can use the SQL Server reports from within the Management Studio to analyze the database and table sizes. Or, you can use a set of queries . I find queries often faster to use because I can tweak them the way I want them.  But be aware that these queries are non-documented and non-supported and may change when the product team wants to change them. If you have multiple Project Collections, find out which might have problems: (Disclaimer: The queries below work on TFS 2010. They will not work on Dev-11, since the table structure have been changed.  I will try to update them for Dev-11 when it is released.) Open a SQL Management Studio session onto the SQL Server where you have your TFS Databases. Use the query below to find the Project Collection databases and their sizes, in descending size order.  use master select DB_NAME(database_id) AS DBName, (size/128) SizeInMB FROM sys.master_files where type=0 and substring(db_name(database_id),1,4)='Tfs_' and DB_NAME(database_id)<>'Tfs_Configuration' order by size desc Doing this on one of our SQL servers gives the following results: It is pretty easy to see on which collection to start the work   Find out which tables are possibly too large Keep a special watch out for the Tfs_Attachment table. Use the script at the bottom of Grant’s blog to find the table sizes in descending size order. In our case we got this result: From Grant’s blog we learnt that the tbl_Content is in the Version Control category, so the major only big issue we have here is the tbl_AttachmentContent.   Find out which team projects have possibly too large attachments In order to use the TAC to find and eventually delete attachment data we need to find out which team projects have these attachments. The team project is a required parameter to the TAC. Use the following query to find this, replace the collection database name with whatever applies in your case:   use Tfs_DefaultCollection select p.projectname, sum(a.compressedlength)/1024/1024 as sizeInMB from dbo.tbl_Attachment as a inner join tbl_testrun as tr on a.testrunid=tr.testrunid inner join tbl_project as p on p.projectid=tr.projectid group by p.projectname order by sum(a.compressedlength) desc In our case we got this result (had to remove some names), out of more than 100 team projects accumulated over quite some years: As can be seen here it is pretty obvious the “Byggtjeneste – Projects” are the main team project to take care of, with the ones on lines 2-4 as the next ones.  Check which attachment types takes up the most space It can be nice to know which attachment types takes up the space, so run the following query: use Tfs_DefaultCollection select a.attachmenttype, sum(a.compressedlength)/1024/1024 as sizeInMB from dbo.tbl_Attachment as a inner join tbl_testrun as tr on a.testrunid=tr.testrunid inner join tbl_project as p on p.projectid=tr.projectid group by a.attachmenttype order by sum(a.compressedlength) desc We then got this result: From this it is pretty obvious that the problem here is the binary files, as also mentioned in Anu’s blog. Check which file types, by their extension, takes up the most space Run the following query use Tfs_DefaultCollection select SUBSTRING(filename,len(filename)-CHARINDEX('.',REVERSE(filename))+2,999)as Extension, sum(compressedlength)/1024 as SizeInKB from tbl_Attachment group by SUBSTRING(filename,len(filename)-CHARINDEX('.',REVERSE(filename))+2,999) order by sum(compressedlength) desc This gives a result like this:   Now you should have collected enough information to tell you what to do – if you got to do something, and some of the information you need in order to set up your TAC settings file, both for a cleanup and for scheduled maintenance later.    Get your TFS server and environment properly set up Even if you have got the problem or if have yet not got the problem, you should ensure the TFS server is set up so that the risk of getting into this problem is minimized.  To ensure this you should install the following set of updates and components. The assumption is that your TFS Server is at SP1 level. Install the QFE for KB2608743 – which also contains detailed instructions on its use, download from here. The QFE changes the default settings to not upload deployed binaries, which are used in automated test runs. Binaries will still be uploaded if: Code coverage is enabled in the test settings. You change the UploadDeploymentItem to true in the testsettings file. Be aware that this might be reset back to false by another user which haven't installed this QFE. The hotfix should be installed to The build servers (the build agents) The machine hosting the Test Controller Local development computers (Visual Studio) Local test computers (MTM) It is not required to install it to the TFS Server, test agents or the build controller – it has no effect on these programs. If you use the SQL Server 2008 R2 you should also install the CU 10 (or later).  This CU fixes a potential problem of hanging “ghost” files.  This seems to happen only in certain trigger situations, but to ensure it doesn’t bite you, it is better to make sure this CU is installed. There is no such CU for SQL Server 2008 pre-R2 Work around:  If you suspect hanging ghost files, they can be – with some mental effort, deduced from the ghost counters using the following SQL query: use master SELECT DB_NAME(database_id) as 'database',OBJECT_NAME(object_id) as 'objectname', index_type_desc,ghost_record_count,version_ghost_record_count,record_count,avg_record_size_in_bytes FROM sys.dm_db_index_physical_stats (DB_ID(N'<DatabaseName>'), OBJECT_ID(N'<TableName>'), NULL, NULL , 'DETAILED') The problem is a stalled ghost cleanup process.  Restarting the SQL server after having stopped all components that depends on it, like the TFS Server and SPS services – that is all applications that connect to the SQL server. Then restart the SQL server, and finally start up all dependent processes again.  (I would guess a complete server reboot would do the trick too.) After this the ghost cleanup process will run properly again. The fix will come in the next CU cycle for SQL Server R2 SP1.  The R2 pre-SP1 and R2 SP1 have separate maintenance cycles, and are maintained individually. Each have its own set of CU’s. When it comes I will add the link here to that CU. The "hanging ghost file” issue came up after one have run the TAC, and deleted enourmes amount of data.  The SQL Server can get into this hanging state (without the QFE) in certain cases due to this. And of course, install and set up the Test Attachment Cleaner command line power tool.  This should be done following some guidelines from Ravi Shanker: “When you run TAC, ensure that you are deleting small chunks of data at regular intervals (say run TAC every night at 3AM to delete data that is between age 730 to 731 days) – this will ensure that small amounts of data are being deleted and SQL ghosted record cleanup can catch up with the number of deletes performed. “ This rule minimizes the risk of the ghosted hang problem to occur, and further makes it easier for the SQL server ghosting process to work smoothly. “Run DBCC SHRINKDB post the ghosted records are cleaned up to physically reclaim the space on the file system” This is the last step in a 3 step process of removing SQL server data. First they are logically deleted. Then they are cleaned out by the ghosting process, and finally removed using the shrinkdb command. Cleaning out the attachments The TAC is run from the command line using a set of parameters and controlled by a settingsfile.  The parameters point out a server uri including the team project collection and also point at a specific team project. So in order to run this for multiple team projects regularly one has to set up a script to run the TAC multiple times, once for each team project.  When you install the TAC there is a very useful readme file in the same directory. When the deployment binaries are published to the TFS server, ALL items are published up from the deployment folder. That often means much more files than you would assume are necessary. This is a brute force technique. It works, but you need to take care when cleaning up. Grant has shown how their settings file looks in his blog post, removing all attachments older than 180 days , as long as there are no active workitems connected to them. This setting can be useful to clean out all items, both in a clean-up once operation, and in a general There are two scenarios we need to consider: Cleaning up an existing overgrown database Maintaining a server to avoid an overgrown database using scheduled TAC   1. Cleaning up a database which has grown too big due to these attachments. This job is a “Once” job.  We do this once and then move on to make sure it won’t happen again, by taking the actions in 2) below.  In this scenario you should only consider the large files. Your goal should be to simply reduce the size, and don’t bother about  the smaller stuff. That can be left a scheduled TAC cleanup ( 2 below). Here you can use a very general settings file, and just remove the large attachments, or you can choose to remove any old items.  Grant’s settings file is an example of the last one.  A settings file to remove only large attachments could look like this: <!-- Scenario : Remove large files --> <DeletionCriteria> <TestRun /> <Attachment> <SizeInMB GreaterThan="10" /> </Attachment> </DeletionCriteria> Or like this: If you want only to remove dll’s and pdb’s about that size, add an Extensions-section.  Without that section, all extensions will be deleted. <!-- Scenario : Remove large files of type dll's and pdb's --> <DeletionCriteria> <TestRun /> <Attachment> <SizeInMB GreaterThan="10" /> <Extensions> <Include value="dll" /> <Include value="pdb" /> </Extensions> </Attachment> </DeletionCriteria> Before you start up your scheduled maintenance, you should clear out all older items. 2. Scheduled maintenance using the TAC If you run a schedule every night, and remove old items, and also remove them in small batches.  It is important to run this often, like every night, in order to keep the number of deleted items low. That way the SQL ghost process works better. One approach could be to delete all items older than some number of days, let’s say 180 days. This could be combined with restricting it to keep attachments with active or resolved bugs.  Doing this every night ensures that only small amounts of data is deleted. <!-- Scenario : Remove old items except if they have active or resolved bugs --> <DeletionCriteria> <TestRun> <AgeInDays OlderThan="180" /> </TestRun> <Attachment /> <LinkedBugs> <Exclude state="Active" /> <Exclude state="Resolved"/> </LinkedBugs> </DeletionCriteria> In my experience there are projects which are left with active or resolved workitems, akthough no further work is done.  It can be wise to have a cleanup process with no restrictions on linked bugs at all. Note that you then have to remove the whole LinkedBugs section. A approach which could work better here is to do a two step approach, use the schedule above to with no LinkedBugs as a sweeper cleaning task taking away all data older than you could care about.  Then have another scheduled TAC task to take out more specifically attachments that you are not likely to use. This task could be much more specific, and based on your analysis clean out what you know is troublesome data. <!-- Scenario : Remove specific files early --> <DeletionCriteria> <TestRun > <AgeInDays OlderThan="30" /> </TestRun> <Attachment> <SizeInMB GreaterThan="10" /> <Extensions> <Include value="iTrace"/> <Include value="dll"/> <Include value="pdb"/> <Include value="wmv"/> </Extensions> </Attachment> <LinkedBugs> <Exclude state="Active" /> <Exclude state="Resolved" /> </LinkedBugs> </DeletionCriteria> The readme document for the TAC says that it recognizes “internal” extensions, but it does recognize any extension. To run the tool do the following command: tcmpt attachmentcleanup /collection:your_tfs_collection_url /teamproject:your_team_project /settingsfile:path_to_settingsfile /outputfile:%temp%/teamproject.tcmpt.log /mode:delete   Shrinking the database You could run a shrink database command after the TAC has run in cases where there are a lot of data being deleted.  In this case you SHOULD do it, to free up all that space.  But, after the shrink operation you should do a rebuild indexes, since the shrink operation will leave the database in a very fragmented state, which will reduce performance. Note that you need to rebuild indexes, reorganizing is not enough. For smaller amounts of data you should NOT shrink the database, since the data will be reused by the SQL server when it need to add more records.  In fact, it is regarded as a bad practice to shrink the database regularly.  So on a daily maintenance schedule you should NOT shrink the database. To shrink the database you do a DBCC SHRINKDATABASE command, and then follow up with a DBCC INDEXDEFRAG afterwards.  I find the easiest way to do this is to create a SQL Maintenance plan including the Shrink Database Task and the Rebuild Index Task and just execute it when you need to do this.

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• Metro: Introduction to CSS 3 Grid Layout

  - by Stephen.Walther

  The purpose of this blog post is to provide you with a quick introduction to the new W3C CSS 3 Grid Layout standard. You can use CSS Grid Layout in Metro style applications written with JavaScript to lay out the content of an HTML page. CSS Grid Layout provides you with all of the benefits of using HTML tables for layout without requiring you to actually use any HTML table elements. Doing Page Layouts without Tables Back in the 1990’s, if you wanted to create a fancy website, then you would use HTML tables for layout. For example, if you wanted to create a standard three-column page layout then you would create an HTML table with three columns like this: <table height="100%"> <tr> <td valign="top" width="300px" bgcolor="red"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </td> <td valign="top" bgcolor="green"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </td> <td valign="top" width="300px" bgcolor="blue"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </td> </tr> </table> When the table above gets rendered out to a browser, you end up with the following three-column layout: The width of the left and right columns is fixed – the width of the middle column expands or contracts depending on the width of the browser. Sometime around the year 2005, everyone decided that using tables for layout was a bad idea. Instead of using tables for layout — it was collectively decided by the spirit of the Web — you should use Cascading Style Sheets instead. Why is using HTML tables for layout bad? Using tables for layout breaks the semantics of the TABLE element. A TABLE element should be used only for displaying tabular information such as train schedules or moon phases. Using tables for layout is bad for accessibility (The Web Content Accessibility Guidelines 1.0 is explicit about this) and using tables for layout is bad for separating content from layout (see http://CSSZenGarden.com). Post 2005, anyone who used HTML tables for layout were encouraged to hold their heads down in shame. That’s all well and good, but the problem with using CSS for layout is that it can be more difficult to work with CSS than HTML tables. For example, to achieve a standard three-column layout, you either need to use absolute positioning or floats. Here’s a three-column layout with floats: <style type="text/css"> #container { min-width: 800px; } #leftColumn { float: left; width: 300px; height: 100%; background-color:red; } #middleColumn { background-color:green; height: 100%; } #rightColumn { float: right; width: 300px; height: 100%; background-color:blue; } </style> <div id="container"> <div id="rightColumn"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </div> <div id="leftColumn"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </div> <div id="middleColumn"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </div> </div> The page above contains four DIV elements: a container DIV which contains a leftColumn, middleColumn, and rightColumn DIV. The leftColumn DIV element is floated to the left and the rightColumn DIV element is floated to the right. Notice that the rightColumn DIV appears in the page before the middleColumn DIV – this unintuitive ordering is necessary to get the floats to work correctly (see http://stackoverflow.com/questions/533607/css-three-column-layout-problem). The page above (almost) works with the most recent versions of most browsers. For example, you get the correct three-column layout in both Firefox and Chrome: And the layout mostly works with Internet Explorer 9 except for the fact that for some strange reason the min-width doesn’t work so when you shrink the width of your browser, you can get the following unwanted layout: Notice how the middle column (the green column) bleeds to the left and right. People have solved these issues with more complicated CSS. For example, see: http://matthewjamestaylor.com/blog/holy-grail-no-quirks-mode.htm But, at this point, no one could argue that using CSS is easier or more intuitive than tables. It takes work to get a layout with CSS and we know that we could achieve the same layout more easily using HTML tables. Using CSS Grid Layout CSS Grid Layout is a new W3C standard which provides you with all of the benefits of using HTML tables for layout without the disadvantage of using an HTML TABLE element. In other words, CSS Grid Layout enables you to perform table layouts using pure Cascading Style Sheets. The CSS Grid Layout standard is still in a “Working Draft” state (it is not finalized) and it is located here: http://www.w3.org/TR/css3-grid-layout/ The CSS Grid Layout standard is only supported by Internet Explorer 10 and there are no signs that any browser other than Internet Explorer will support this standard in the near future. This means that it is only practical to take advantage of CSS Grid Layout when building Metro style applications with JavaScript. Here’s how you can create a standard three-column layout using a CSS Grid Layout: <!DOCTYPE html> <html> <head> <style type="text/css"> html, body, #container { height: 100%; padding: 0px; margin: 0px; } #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100%; } #leftColumn { -ms-grid-column: 1; background-color:red; } #middleColumn { -ms-grid-column: 2; background-color:green; } #rightColumn { -ms-grid-column: 3; background-color:blue; } </style> </head> <body> <div id="container"> <div id="leftColumn"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </div> <div id="middleColumn"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </div> <div id="rightColumn"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </div> </div> </body> </html> When the page above is rendered in Internet Explorer 10, you get a standard three-column layout: The page above contains four DIV elements: a container DIV which contains a leftColumn DIV, middleColumn DIV, and rightColumn DIV. The container DIV is set to Grid display mode with the following CSS rule: #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100%; } The display property is set to the value “-ms-grid”. This property causes the container DIV to lay out its child elements in a grid. (Notice that you use “-ms-grid” instead of “grid”. The “-ms-“ prefix is used because the CSS Grid Layout standard is still preliminary. This implementation only works with IE10 and it might change before the final release.) The grid columns and rows are defined with the “-ms-grid-columns” and “-ms-grid-rows” properties. The style rule above creates a grid with three columns and one row. The left and right columns are fixed sized at 300 pixels. The middle column sizes automatically depending on the remaining space available. The leftColumn, middleColumn, and rightColumn DIVs are positioned within the container grid element with the following CSS rules: #leftColumn { -ms-grid-column: 1; background-color:red; } #middleColumn { -ms-grid-column: 2; background-color:green; } #rightColumn { -ms-grid-column: 3; background-color:blue; } The “-ms-grid-column” property is used to specify the column associated with the element selected by the style sheet selector. The leftColumn DIV is positioned in the first grid column, the middleColumn DIV is positioned in the second grid column, and the rightColumn DIV is positioned in the third grid column. I find using CSS Grid Layout to be just as intuitive as using an HTML table for layout. You define your columns and rows and then you position different elements within these columns and rows. Very straightforward. Creating Multiple Columns and Rows In the previous section, we created a super simple three-column layout. This layout contained only a single row. In this section, let’s create a slightly more complicated layout which contains more than one row: The following page contains a header row, a content row, and a footer row. The content row contains three columns: <!DOCTYPE html> <html> <head> <style type="text/css"> html, body, #container { height: 100%; padding: 0px; margin: 0px; } #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100px 1fr 100px; } #header { -ms-grid-column: 1; -ms-grid-column-span: 3; -ms-grid-row: 1; background-color: yellow; } #leftColumn { -ms-grid-column: 1; -ms-grid-row: 2; background-color:red; } #middleColumn { -ms-grid-column: 2; -ms-grid-row: 2; background-color:green; } #rightColumn { -ms-grid-column: 3; -ms-grid-row: 2; background-color:blue; } #footer { -ms-grid-column: 1; -ms-grid-column-span: 3; -ms-grid-row: 3; background-color: orange; } </style> </head> <body> <div id="container"> <div id="header"> Header, Header, Header </div> <div id="leftColumn"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </div> <div id="middleColumn"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </div> <div id="rightColumn"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </div> <div id="footer"> Footer, Footer, Footer </div> </div> </body> </html> In the page above, the grid layout is created with the following rule which creates a grid with three rows and three columns: #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100px 1fr 100px; } The header is created with the following rule: #header { -ms-grid-column: 1; -ms-grid-column-span: 3; -ms-grid-row: 1; background-color: yellow; } The header is positioned in column 1 and row 1. Furthermore, notice that the “-ms-grid-column-span” property is used to span the header across three columns. CSS Grid Layout and Fractional Units When you use CSS Grid Layout, you can take advantage of fractional units. Fractional units provide you with an easy way of dividing up remaining space in a page. Imagine, for example, that you want to create a three-column page layout. You want the size of the first column to be fixed at 200 pixels and you want to divide the remaining space among the remaining three columns. The width of the second column is equal to the combined width of the third and fourth columns. The following CSS rule creates four columns with the desired widths: #container { display: -ms-grid; -ms-grid-columns: 200px 2fr 1fr 1fr; -ms-grid-rows: 1fr; } The fr unit represents a fraction. The grid above contains four columns. The second column is two times the size (2fr) of the third (1fr) and fourth (1fr) columns. When you use the fractional unit, the remaining space is divided up using fractional amounts. Notice that the single row is set to a height of 1fr. The single grid row gobbles up the entire vertical space. Here’s the entire HTML page: <!DOCTYPE html> <html> <head> <style type="text/css"> html, body, #container { height: 100%; padding: 0px; margin: 0px; } #container { display: -ms-grid; -ms-grid-columns: 200px 2fr 1fr 1fr; -ms-grid-rows: 1fr; } #firstColumn { -ms-grid-column: 1; background-color:red; } #secondColumn { -ms-grid-column: 2; background-color:green; } #thirdColumn { -ms-grid-column: 3; background-color:blue; } #fourthColumn { -ms-grid-column: 4; background-color:orange; } </style> </head> <body> <div id="container"> <div id="firstColumn"> First Column, First Column, First Column </div> <div id="secondColumn"> Second Column, Second Column, Second Column </div> <div id="thirdColumn"> Third Column, Third Column, Third Column </div> <div id="fourthColumn"> Fourth Column, Fourth Column, Fourth Column </div> </div> </body> </html>   Summary There is more in the CSS 3 Grid Layout standard than discussed in this blog post. My goal was to describe the basics. If you want to learn more than you can read through the entire standard at http://www.w3.org/TR/css3-grid-layout/ In this blog post, I described some of the difficulties that you might encounter when attempting to replace HTML tables with Cascading Style Sheets when laying out a web page. I explained how you can take advantage of the CSS 3 Grid Layout standard to avoid these problems when building Metro style applications using JavaScript. CSS 3 Grid Layout provides you with all of the benefits of using HTML tables for laying out a page without requiring you to use HTML table elements.

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• Is your team is a high-performing team?

  As a child I can remember looking out of the car window as my father drove along the Interstate in Florida while seeing prisoners wearing bright orange jump suits and prison guards keeping a watchful eye on them. The prisoners were taking part in a prison road gang. These road gangs were formed to help the state maintain the state highway infrastructure. The prisoner’s primary responsibilities are to pick up trash and debris from the roadway. This is a prime example of a work group or working group used by most prison systems in the United States. Work groups or working groups can be defined as a collection of individuals or entities working together to achieve a specific goal or accomplish a specific set of tasks. Typically these groups are only established for a short period of time and are dissolved once the desired outcome has been achieved. More often than not group members usually feel as though they are expendable to the group and some even dread that they are even in the group. "A team is a small number of people with complementary skills who are committed to a common purpose, performance goals, and approach for which they are mutually accountable." (Katzenbach and Smith, 1993) So how do you determine that a team is a high-performing team?  This can be determined by three base line criteria that include: consistently high quality output, the promotion of personal growth and well being of all team members, and most importantly the ability to learn and grow as a unit. Initially, a team can successfully create high-performing output without meeting all three criteria, however this will erode over time because team members will feel detached from the group or that they are not growing then the quality of the output will decline. High performing teams are similar to work groups because they both utilize a collection of individuals or entities to accomplish tasks. What distinguish a high-performing team from a work group are its characteristics. High-performing teams contain five core characteristics. These characteristics are what separate a group from a team. The five characteristics of a high-performing team include: Purpose, Performance Measures, People with Tasks and Relationship Skills, Process, and Preparation and Practice. A high-performing team is much more than a work group, and typically has a life cycle that can vary from team to team. The standard team lifecycle consists of five states and is comparable to a human life cycle. The five states of a high-performing team lifecycle include: Formulating, Storming, Normalizing, Performing, and Adjourning. The Formulating State of a team is first realized when the team members are first defined and roles are assigned to all members. This initial stage is very important because it can set the tone for the team and can ultimately determine its success or failure. In addition, this stage requires the team to have a strong leader because team members are normally unclear about specific roles, specific obstacles and goals that my lay ahead of them.  Finally, this stage is where most team members initially meet one another prior to working as a team unless the team members already know each other. The Storming State normally arrives directly after the formulation of a new team because there are still a lot of unknowns amongst the newly formed assembly. As a general rule most of the parties involved in the team are still getting used to the workload, pace of work, deadlines and the validity of various tasks that need to be performed by the group.  In this state everything is questioned because there are so many unknowns. Items commonly questioned include the credentials of others on the team, the actual validity of a project, and the leadership abilities of the team leader.  This can be exemplified by looking at the interactions between animals when they first meet.  If we look at a scenario where two people are walking directly toward each other with their dogs. The dogs will automatically enter the Storming State because they do not know the other dog. Typically in this situation, they attempt to define which is more dominating via play or fighting depending on how the dogs interact with each other. Once dominance has been defined and accepted by both dogs then they will either want to play or leave depending on how the dogs interacted and other environmental variables. Once the Storming State has been realized then the Normalizing State takes over. This state is entered by a team once all the questions of the Storming State have been answered and the team has been tested by a few tasks or projects.  Typically, participants in the team are filled with energy, and comradery, and a strong alliance with team goals and objectives.  A high school football team is a perfect example of the Normalizing State when they start their season.  The player positions have been assigned, the depth chart has been filled and everyone is focused on winning each game. All of the players encourage and expect each other to perform at the best of their abilities and are united by competition from other teams. The Performing State is achieved by a team when its history, working habits, and culture solidify the team as one working unit. In this state team members can anticipate specific behaviors, attitudes, reactions, and challenges are seen as opportunities and not problems. Additionally, each team member knows their role in the team’s success, and the roles of others. This is the most productive state of a group and is where all the time invested working together really pays off. If you look at an Olympic figure skating team skate you can easily see how the time spent working together benefits their performance. They skate as one unit even though it is comprised of two skaters. Each skater has their routine completely memorized as well as their partners. This allows them to anticipate each other’s moves on the ice makes their skating look effortless. The final state of a team is the Adjourning State. This state is where accomplishments by the team and each individual team member are recognized. Additionally, this state also allows for reflection of the interactions between team members, work accomplished and challenges that were faced. Finally, the team celebrates the challenges they have faced and overcome as a unit. Currently in the workplace teams are divided into two different types: Co-located and Distributed Teams. Co-located teams defined as the traditional group of people working together in an office, according to Andy Singleton of Assembla. This traditional type of a team has dominated business in the past due to inadequate technology, which forced workers to primarily interact with one another via face to face meetings.  Team meetings are primarily lead by the person with the highest status in the company. Having personally, participated in meetings of this type, usually a select few of the team members dominate the flow of communication which reduces the input of others in group discussions. Since discussions are dominated by a select few individuals the discussions and group discussion are skewed in favor of the individuals who communicate the most in meetings. In addition, Team members might not give their full opinions on a topic of discussion in part not to offend or create controversy amongst the team and can alter decision made in meetings towards those of the opinions of the dominating team members. Distributed teams are by definition spread across an area or subdivided into separate sections. That is exactly what distributed teams when compared to a more traditional team. It is common place for distributed teams to have team members across town, in the next state, across the country and even with the advances in technology over the last 20 year across the world. These teams allow for more diversity compared to the other type of teams because they allow for more flexibility regarding location. A team could consist of a 30 year old male Italian project manager from New York, a 50 year old female Hispanic from California and a collection of programmers from India because technology allows them to communicate as if they were standing next to one another.  In addition, distributed team members consult with more team members prior to making decisions compared to traditional teams, and take longer to come to decisions due to the changes in time zones and cultural events. However, team members feel more empowered to speak out when they do not agree with the team and to notify others of potential issues regarding the work that the team is doing. Virtual teams which are a subset of the distributed team type is changing organizational strategies due to the fact that a team can now in essence be working 24 hrs a day because of utilizing employees in various time zones and locations.  A primary example of this is with customer services departments, a company can have multiple call centers spread across multiple time zones allowing them to appear to be open 24 hours a day while all a employees work from 9AM to 5 PM every day. Virtual teams also allow human resources departments to go after the best talent for the company regardless of where the potential employee works because they will be a part of a virtual team all that is need is the proper technology to be setup to allow everyone to communicate. In addition to allowing employees to work from home, the company can save space and resources by not having to provide a desk for every team member. In fact, those team members that randomly come into the office can actually share one desk amongst multiple people. This is definitely a cost cutting plus given the current state of the economy. One thing that can turn a team into a high-performing team is leadership. High-performing team leaders need to focus on investing in ongoing personal development, provide team members with direction, structure, and resources needed to accomplish their work, make the right interventions at the right time, and help the team manage boundaries between the team and various external parties involved in the teams work. A team leader needs to invest in ongoing personal development in order to effectively manage their team. People have said that attitude is everything; this is very true about leaders and leadership. A team takes on the attitudes and behaviors of its leaders. This can potentially harm the team and the team’s output. Leaders must concentrate on self-awareness, and understanding their team’s group dynamics to fully understand how to lead them. In addition, always learning new leadership techniques from other effective leaders is also very beneficial. Providing team members with direction, structure, and resources that they need to accomplish their work collectively sounds easy, but it is not.  Leaders need to be able to effectively communicate with their team on how their work helps the company reach for its organizational vision. Conversely, the leader needs to allow his team to work autonomously within specific guidelines to turn the company’s vision into a reality.  This being said the team must be appropriately staffed according to the size of the team’s tasks and their complexity. These tasks should be clear, and be meaningful to the company’s objectives and allow for feedback to be exchanged with the leader and the team member and the leader and upper management. Now if the team is properly staffed, and has a clear and full understanding of what is to be done; the company also must supply the workers with the proper tools to achieve the tasks that they are asked to do. No one should be asked to dig a hole without being given a shovel.  Finally, leaders must reward their team members for accomplishments that they achieve. Awards could range from just a simple congratulatory email, a party to close the completion of a large project, or other monetary rewards. Managing boundaries is very important for team leaders because it can alter attitudes of team members and can add undue stress to the team which will force them to loose focus on the tasks at hand for the group. Team leaders should promote communication between team members so that burdens are shared amongst the team and solutions can be derived from hearing the opinions of multiple sources. This also reinforces team camaraderie and working as a unit. Team leaders must manage the type and timing of interventions as to not create an even bigger mess within the team. Poorly timed interventions can really deflate team members and make them question themselves. This could really increase further and undue interventions by the team leader. Typically, the best time for interventions is when the team is just starting to form so that all unproductive behaviors are removed from the team and that it can retain focus on its agenda. If an intervention is effectively executed the team will feel energized about the work that they are doing, promote communication and interaction amongst the group and improve moral overall. High-performing teams are very import to organizations because they consistently produce high quality output and develop a collective purpose for their work. This drive to succeed allows team members to utilize specific talents allowing for growth in these areas.  In addition, these team members usually take on a sense of ownership with their projects and feel that the other team members are irreplaceable. References: http://blog.assembla.com/assemblablog/tabid/12618/bid/3127/Three-ways-to-organize-your-team-co-located-outsourced-or-global.aspx Katzenbach, J.R. & Smith, D.K. (1993). The Wisdom of Teams: Creating the High-performance Organization. Boston: Harvard Business School.

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• Sorting Algorithms

  - by MarkPearl

  General Every time I go back to university I find myself wading through sorting algorithms and their implementation in C++. Up to now I haven’t really appreciated their true value. However as I discovered this last week with Dictionaries in C# – having a knowledge of some basic programming principles can greatly improve the performance of a system and make one think twice about how to tackle a problem. I’m going to cover briefly in this post the following: Selection Sort Insertion Sort Shellsort Quicksort Mergesort Heapsort (not complete) Selection Sort Array based selection sort is a simple approach to sorting an unsorted array. Simply put, it repeats two basic steps to achieve a sorted collection. It starts with a collection of data and repeatedly parses it, each time sorting out one element and reducing the size of the next iteration of parsed data by one. So the first iteration would go something like this… Go through the entire array of data and find the lowest value Place the value at the front of the array The second iteration would go something like this… Go through the array from position two (position one has already been sorted with the smallest value) and find the next lowest value in the array. Place the value at the second position in the array This process would be completed until the entire array had been sorted. A positive about selection sort is that it does not make many item movements. In fact, in a worst case scenario every items is only moved once. Selection sort is however a comparison intensive sort. If you had 10 items in a collection, just to parse the collection you would have 10+9+8+7+6+5+4+3+2=54 comparisons to sort regardless of how sorted the collection was to start with. If you think about it, if you applied selection sort to a collection already sorted, you would still perform relatively the same number of iterations as if it was not sorted at all. Many of the following algorithms try and reduce the number of comparisons if the list is already sorted – leaving one with a best case and worst case scenario for comparisons. Likewise different approaches have different levels of item movement. Depending on what is more expensive, one may give priority to one approach compared to another based on what is more expensive, a comparison or a item move. Insertion Sort Insertion sort tries to reduce the number of key comparisons it performs compared to selection sort by not “doing anything” if things are sorted. Assume you had an collection of numbers in the following order… 10 18 25 30 23 17 45 35 There are 8 elements in the list. If we were to start at the front of the list – 10 18 25 & 30 are already sorted. Element 5 (23) however is smaller than element 4 (30) and so needs to be repositioned. We do this by copying the value at element 5 to a temporary holder, and then begin shifting the elements before it up one. So… Element 5 would be copied to a temporary holder 10 18 25 30 23 17 45 35 – T 23 Element 4 would shift to Element 5 10 18 25 30 30 17 45 35 – T 23 Element 3 would shift to Element 4 10 18 25 25 30 17 45 35 – T 23 Element 2 (18) is smaller than the temporary holder so we put the temporary holder value into Element 3. 10 18 23 25 30 17 45 35 – T 23   We now have a sorted list up to element 6. And so we would repeat the same process by moving element 6 to a temporary value and then shifting everything up by one from element 2 to element 5. As you can see, one major setback for this technique is the shifting values up one – this is because up to now we have been considering the collection to be an array. If however the collection was a linked list, we would not need to shift values up, but merely remove the link from the unsorted value and “reinsert” it in a sorted position. Which would reduce the number of transactions performed on the collection. So.. Insertion sort seems to perform better than selection sort – however an implementation is slightly more complicated. This is typical with most sorting algorithms – generally, greater performance leads to greater complexity. Also, insertion sort performs better if a collection of data is already sorted. If for instance you were handed a sorted collection of size n, then only n number of comparisons would need to be performed to verify that it is sorted. It’s important to note that insertion sort (array based) performs a number item moves – every time an item is “out of place” several items before it get shifted up. Shellsort – Diminishing Increment Sort So up to now we have covered Selection Sort & Insertion Sort. Selection Sort makes many comparisons and insertion sort (with an array) has the potential of making many item movements. Shellsort is an approach that takes the normal insertion sort and tries to reduce the number of item movements. In Shellsort, elements in a collection are viewed as sub-collections of a particular size. Each sub-collection is sorted so that the elements that are far apart move closer to their final position. Suppose we had a collection of 15 elements… 10 20 15 45 36 48 7 60 18 50 2 19 43 30 55 First we may view the collection as 7 sub-collections and sort each sublist, lets say at intervals of 7 10 60 55 – 20 18 – 15 50 – 45 2 – 36 19 – 48 43 – 7 30 10 55 60 – 18 20 – 15 50 – 2 45 – 19 36 – 43 48 – 7 30 (Sorted) We then sort each sublist at a smaller inter – lets say 4 10 55 60 18 – 20 15 50 2 – 45 19 36 43 – 48 7 30 10 18 55 60 – 2 15 20 50 – 19 36 43 45 – 7 30 48 (Sorted) We then sort elements at a distance of 1 (i.e. we apply a normal insertion sort) 10 18 55 60 2 15 20 50 19 36 43 45 7 30 48 2 7 10 15 18 19 20 30 36 43 45 48 50 55 (Sorted) The important thing with shellsort is deciding on the increment sequence of each sub-collection. From what I can tell, there isn’t any definitive method and depending on the order of your elements, different increment sequences may perform better than others. There are however certain increment sequences that you may want to avoid. An even based increment sequence (e.g. 2 4 8 16 32 …) should typically be avoided because it does not allow for even elements to be compared with odd elements until the final sort phase – which in a way would negate many of the benefits of using sub-collections. The performance on the number of comparisons and item movements of Shellsort is hard to determine, however it is considered to be considerably better than the normal insertion sort. Quicksort Quicksort uses a divide and conquer approach to sort a collection of items. The collection is divided into two sub-collections – and the two sub-collections are sorted and combined into one list in such a way that the combined list is sorted. The algorithm is in general pseudo code below… Divide the collection into two sub-collections Quicksort the lower sub-collection Quicksort the upper sub-collection Combine the lower & upper sub-collection together As hinted at above, quicksort uses recursion in its implementation. The real trick with quicksort is to get the lower and upper sub-collections to be of equal size. The size of a sub-collection is determined by what value the pivot is. Once a pivot is determined, one would partition to sub-collections and then repeat the process on each sub collection until you reach the base case. With quicksort, the work is done when dividing the sub-collections into lower & upper collections. The actual combining of the lower & upper sub-collections at the end is relatively simple since every element in the lower sub-collection is smaller than the smallest element in the upper sub-collection. Mergesort With quicksort, the average-case complexity was O(nlog2n) however the worst case complexity was still O(N*N). Mergesort improves on quicksort by always having a complexity of O(nlog2n) regardless of the best or worst case. So how does it do this? Mergesort makes use of the divide and conquer approach to partition a collection into two sub-collections. It then sorts each sub-collection and combines the sorted sub-collections into one sorted collection. The general algorithm for mergesort is as follows… Divide the collection into two sub-collections Mergesort the first sub-collection Mergesort the second sub-collection Merge the first sub-collection and the second sub-collection As you can see.. it still pretty much looks like quicksort – so lets see where it differs… Firstly, mergesort differs from quicksort in how it partitions the sub-collections. Instead of having a pivot – merge sort partitions each sub-collection based on size so that the first and second sub-collection of relatively the same size. This dividing keeps getting repeated until the sub-collections are the size of a single element. If a sub-collection is one element in size – it is now sorted! So the trick is how do we put all these sub-collections together so that they maintain their sorted order. Sorted sub-collections are merged into a sorted collection by comparing the elements of the sub-collection and then adjusting the sorted collection. Lets have a look at a few examples… Assume 2 sub-collections with 1 element each 10 & 20 Compare the first element of the first sub-collection with the first element of the second sub-collection. Take the smallest of the two and place it as the first element in the sorted collection. In this scenario 10 is smaller than 20 so 10 is taken from sub-collection 1 leaving that sub-collection empty, which means by default the next smallest element is in sub-collection 2 (20). So the sorted collection would be 10 20 Lets assume 2 sub-collections with 2 elements each 10 20 & 15 19 So… again we would Compare 10 with 15 – 10 is the winner so we add it to our sorted collection (10) leaving us with 20 & 15 19 Compare 20 with 15 – 15 is the winner so we add it to our sorted collection (10 15) leaving us with 20 & 19 Compare 20 with 19 – 19 is the winner so we add it to our sorted collection (10 15 19) leaving us with 20 & _ 20 is by default the winner so our sorted collection is 10 15 19 20. Make sense? Heapsort (still needs to be completed) So by now I am tired of sorting algorithms and trying to remember why they were so important. I think every year I go through this stuff I wonder to myself why are we made to learn about selection sort and insertion sort if they are so bad – why didn’t we just skip to Mergesort & Quicksort. I guess the only explanation I have for this is that sometimes you learn things so that you can implement them in future – and other times you learn things so that you know it isn’t the best way of implementing things and that you don’t need to implement it in future. Anyhow… luckily this is going to be the last one of my sorts for today. The first step in heapsort is to convert a collection of data into a heap. After the data is converted into a heap, sorting begins… So what is the definition of a heap? If we have to convert a collection of data into a heap, how do we know when it is a heap and when it is not? The definition of a heap is as follows: A heap is a list in which each element contains a key, such that the key in the element at position k in the list is at least as large as the key in the element at position 2k +1 (if it exists) and 2k + 2 (if it exists). Does that make sense? At first glance I’m thinking what the heck??? But then after re-reading my notes I see that we are doing something different – up to now we have really looked at data as an array or sequential collection of data that we need to sort – a heap represents data in a slightly different way – although the data is stored in a sequential collection, for a sequential collection of data to be in a valid heap – it is “semi sorted”. Let me try and explain a bit further with an example… Example 1 of Potential Heap Data Assume we had a collection of numbers as follows 1[1] 2[2] 3[3] 4[4] 5[5] 6[6] For this to be a valid heap element with value of 1 at position [1] needs to be greater or equal to the element at position [3] (2k +1) and position [4] (2k +2). So in the above example, the collection of numbers is not in a valid heap. Example 2 of Potential Heap Data Lets look at another collection of numbers as follows 6[1] 5[2] 4[3] 3[4] 2[5] 1[6] Is this a valid heap? Well… element with the value 6 at position 1 must be greater or equal to the element at position [3] and position [4]. Is 6 > 4 and 6 > 3? Yes it is. Lets look at element 5 as position 2. It must be greater than the values at [4] & [5]. Is 5 > 3 and 5 > 2? Yes it is. If you continued to examine this second collection of data you would find that it is in a valid heap based on the definition of a heap.

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• Metro: Introduction to CSS 3 Grid Layout

  - by Stephen.Walther

  The purpose of this blog post is to provide you with a quick introduction to the new W3C CSS 3 Grid Layout standard. You can use CSS Grid Layout in Metro style applications written with JavaScript to lay out the content of an HTML page. CSS Grid Layout provides you with all of the benefits of using HTML tables for layout without requiring you to actually use any HTML table elements. Doing Page Layouts without Tables Back in the 1990’s, if you wanted to create a fancy website, then you would use HTML tables for layout. For example, if you wanted to create a standard three-column page layout then you would create an HTML table with three columns like this: <table height="100%"> <tr> <td valign="top" width="300px" bgcolor="red"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </td> <td valign="top" bgcolor="green"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </td> <td valign="top" width="300px" bgcolor="blue"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </td> </tr> </table> When the table above gets rendered out to a browser, you end up with the following three-column layout: The width of the left and right columns is fixed – the width of the middle column expands or contracts depending on the width of the browser. Sometime around the year 2005, everyone decided that using tables for layout was a bad idea. Instead of using tables for layout — it was collectively decided by the spirit of the Web — you should use Cascading Style Sheets instead. Why is using HTML tables for layout bad? Using tables for layout breaks the semantics of the TABLE element. A TABLE element should be used only for displaying tabular information such as train schedules or moon phases. Using tables for layout is bad for accessibility (The Web Content Accessibility Guidelines 1.0 is explicit about this) and using tables for layout is bad for separating content from layout (see http://CSSZenGarden.com). Post 2005, anyone who used HTML tables for layout were encouraged to hold their heads down in shame. That’s all well and good, but the problem with using CSS for layout is that it can be more difficult to work with CSS than HTML tables. For example, to achieve a standard three-column layout, you either need to use absolute positioning or floats. Here’s a three-column layout with floats: <style type="text/css"> #container { min-width: 800px; } #leftColumn { float: left; width: 300px; height: 100%; background-color:red; } #middleColumn { background-color:green; height: 100%; } #rightColumn { float: right; width: 300px; height: 100%; background-color:blue; } </style> <div id="container"> <div id="rightColumn"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </div> <div id="leftColumn"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </div> <div id="middleColumn"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </div> </div> The page above contains four DIV elements: a container DIV which contains a leftColumn, middleColumn, and rightColumn DIV. The leftColumn DIV element is floated to the left and the rightColumn DIV element is floated to the right. Notice that the rightColumn DIV appears in the page before the middleColumn DIV – this unintuitive ordering is necessary to get the floats to work correctly (see http://stackoverflow.com/questions/533607/css-three-column-layout-problem). The page above (almost) works with the most recent versions of most browsers. For example, you get the correct three-column layout in both Firefox and Chrome: And the layout mostly works with Internet Explorer 9 except for the fact that for some strange reason the min-width doesn’t work so when you shrink the width of your browser, you can get the following unwanted layout: Notice how the middle column (the green column) bleeds to the left and right. People have solved these issues with more complicated CSS. For example, see: http://matthewjamestaylor.com/blog/holy-grail-no-quirks-mode.htm But, at this point, no one could argue that using CSS is easier or more intuitive than tables. It takes work to get a layout with CSS and we know that we could achieve the same layout more easily using HTML tables. Using CSS Grid Layout CSS Grid Layout is a new W3C standard which provides you with all of the benefits of using HTML tables for layout without the disadvantage of using an HTML TABLE element. In other words, CSS Grid Layout enables you to perform table layouts using pure Cascading Style Sheets. The CSS Grid Layout standard is still in a “Working Draft” state (it is not finalized) and it is located here: http://www.w3.org/TR/css3-grid-layout/ The CSS Grid Layout standard is only supported by Internet Explorer 10 and there are no signs that any browser other than Internet Explorer will support this standard in the near future. This means that it is only practical to take advantage of CSS Grid Layout when building Metro style applications with JavaScript. Here’s how you can create a standard three-column layout using a CSS Grid Layout: <!DOCTYPE html> <html> <head> <style type="text/css"> html, body, #container { height: 100%; padding: 0px; margin: 0px; } #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100%; } #leftColumn { -ms-grid-column: 1; background-color:red; } #middleColumn { -ms-grid-column: 2; background-color:green; } #rightColumn { -ms-grid-column: 3; background-color:blue; } </style> </head> <body> <div id="container"> <div id="leftColumn"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </div> <div id="middleColumn"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </div> <div id="rightColumn"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </div> </div> </body> </html> When the page above is rendered in Internet Explorer 10, you get a standard three-column layout: The page above contains four DIV elements: a container DIV which contains a leftColumn DIV, middleColumn DIV, and rightColumn DIV. The container DIV is set to Grid display mode with the following CSS rule: #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100%; } The display property is set to the value “-ms-grid”. This property causes the container DIV to lay out its child elements in a grid. (Notice that you use “-ms-grid” instead of “grid”. The “-ms-“ prefix is used because the CSS Grid Layout standard is still preliminary. This implementation only works with IE10 and it might change before the final release.) The grid columns and rows are defined with the “-ms-grid-columns” and “-ms-grid-rows” properties. The style rule above creates a grid with three columns and one row. The left and right columns are fixed sized at 300 pixels. The middle column sizes automatically depending on the remaining space available. The leftColumn, middleColumn, and rightColumn DIVs are positioned within the container grid element with the following CSS rules: #leftColumn { -ms-grid-column: 1; background-color:red; } #middleColumn { -ms-grid-column: 2; background-color:green; } #rightColumn { -ms-grid-column: 3; background-color:blue; } The “-ms-grid-column” property is used to specify the column associated with the element selected by the style sheet selector. The leftColumn DIV is positioned in the first grid column, the middleColumn DIV is positioned in the second grid column, and the rightColumn DIV is positioned in the third grid column. I find using CSS Grid Layout to be just as intuitive as using an HTML table for layout. You define your columns and rows and then you position different elements within these columns and rows. Very straightforward. Creating Multiple Columns and Rows In the previous section, we created a super simple three-column layout. This layout contained only a single row. In this section, let’s create a slightly more complicated layout which contains more than one row: The following page contains a header row, a content row, and a footer row. The content row contains three columns: <!DOCTYPE html> <html> <head> <style type="text/css"> html, body, #container { height: 100%; padding: 0px; margin: 0px; } #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100px 1fr 100px; } #header { -ms-grid-column: 1; -ms-grid-column-span: 3; -ms-grid-row: 1; background-color: yellow; } #leftColumn { -ms-grid-column: 1; -ms-grid-row: 2; background-color:red; } #middleColumn { -ms-grid-column: 2; -ms-grid-row: 2; background-color:green; } #rightColumn { -ms-grid-column: 3; -ms-grid-row: 2; background-color:blue; } #footer { -ms-grid-column: 1; -ms-grid-column-span: 3; -ms-grid-row: 3; background-color: orange; } </style> </head> <body> <div id="container"> <div id="header"> Header, Header, Header </div> <div id="leftColumn"> Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column, Left Column </div> <div id="middleColumn"> Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column, Middle Column </div> <div id="rightColumn"> Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column, Right Column </div> <div id="footer"> Footer, Footer, Footer </div> </div> </body> </html> In the page above, the grid layout is created with the following rule which creates a grid with three rows and three columns: #container { display: -ms-grid; -ms-grid-columns: 300px auto 300px; -ms-grid-rows: 100px 1fr 100px; } The header is created with the following rule: #header { -ms-grid-column: 1; -ms-grid-column-span: 3; -ms-grid-row: 1; background-color: yellow; } The header is positioned in column 1 and row 1. Furthermore, notice that the “-ms-grid-column-span” property is used to span the header across three columns. CSS Grid Layout and Fractional Units When you use CSS Grid Layout, you can take advantage of fractional units. Fractional units provide you with an easy way of dividing up remaining space in a page. Imagine, for example, that you want to create a three-column page layout. You want the size of the first column to be fixed at 200 pixels and you want to divide the remaining space among the remaining three columns. The width of the second column is equal to the combined width of the third and fourth columns. The following CSS rule creates four columns with the desired widths: #container { display: -ms-grid; -ms-grid-columns: 200px 2fr 1fr 1fr; -ms-grid-rows: 1fr; } The fr unit represents a fraction. The grid above contains four columns. The second column is two times the size (2fr) of the third (1fr) and fourth (1fr) columns. When you use the fractional unit, the remaining space is divided up using fractional amounts. Notice that the single row is set to a height of 1fr. The single grid row gobbles up the entire vertical space. Here’s the entire HTML page: <!DOCTYPE html> <html> <head> <style type="text/css"> html, body, #container { height: 100%; padding: 0px; margin: 0px; } #container { display: -ms-grid; -ms-grid-columns: 200px 2fr 1fr 1fr; -ms-grid-rows: 1fr; } #firstColumn { -ms-grid-column: 1; background-color:red; } #secondColumn { -ms-grid-column: 2; background-color:green; } #thirdColumn { -ms-grid-column: 3; background-color:blue; } #fourthColumn { -ms-grid-column: 4; background-color:orange; } </style> </head> <body> <div id="container"> <div id="firstColumn"> First Column, First Column, First Column </div> <div id="secondColumn"> Second Column, Second Column, Second Column </div> <div id="thirdColumn"> Third Column, Third Column, Third Column </div> <div id="fourthColumn"> Fourth Column, Fourth Column, Fourth Column </div> </div> </body> </html>   Summary There is more in the CSS 3 Grid Layout standard than discussed in this blog post. My goal was to describe the basics. If you want to learn more than you can read through the entire standard at http://www.w3.org/TR/css3-grid-layout/ In this blog post, I described some of the difficulties that you might encounter when attempting to replace HTML tables with Cascading Style Sheets when laying out a web page. I explained how you can take advantage of the CSS 3 Grid Layout standard to avoid these problems when building Metro style applications using JavaScript. CSS 3 Grid Layout provides you with all of the benefits of using HTML tables for laying out a page without requiring you to use HTML table elements.

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• CodePlex Daily Summary for Tuesday, March 27, 2012

  CodePlex Daily Summary for Tuesday, March 27, 2012Popular ReleasesHarness: Harness 2.0.2: change to .NET Framework Client Profile bug fix the download dialog auto answer. bug fix setFocus command. add "SendKeys" command. remove "closeAll" command. minor bugs fixed.BugNET Issue Tracker: BugNET 0.9.161: Below is a list of fixes in this release. Bug BGN-2092 - Link in Email "visit your profile" not functional BGN-2083 - Manager of bugnet can not edit project when it is not public BGN-2080 - clicking on a link in the project summary causes error (0.9.152.0) BGN-2070 - Missing Functionality On Feed.aspx BGN-2069 - Calendar View does not work BGN-2068 - Time tracking totals not ok BGN-2067 - Issues List Page Size Bug: Index was out of range. Must be non-negative and less than the si...YAF.NET (aka Yet Another Forum.NET): v1.9.6.1 RTW: v1.9.6.1 FINAL is .NET v4.0 ONLY v1.9.6.1 has: Performance Improvements .NET v4.0 improvements Improved FaceBook Integration More complete change list and discussion here: http://forum.yetanotherforum.net/yaf_postst14201_v1-9-6-1-RTW-Dated--3-26-2012.aspxQuick Performance Monitor: Version 1.8.1: Added option to set main window to be 'Always On Top'. Use context (right-click) menu on graph to toggle.Asp.NET Url Router: v1.0: build for .net 2.0 and .net 4.0SQLinq - use LINQ to generate Ad-Hoc Sql Queries: SQLinq v1.1: Nuget Package:http://nuget.org/packages/sqlinq Install SQLinq via Nuget Change Log:Fixed "SELECT *" bug when no selector is specified Added ".Take(int)" and ".Skip(int)" methods to support paging Added ability to specify "ORDER BY"DbViewSharp: Sql Compact Edition plugins: The SQL CE plugins are new assemblies written to allow DbViewSharp to work with SQL Compact Edition databases. Some features available for Sql Server databases are unavailable because of restrictions in the Compact Edition engine. However there are plans to add different new features as compensation for this. 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• Prime Numbers Code Help

  - by andrew

  Hello Everybody, I am suppose to "write a Java program that reads a positive integer n from standard input, then prints out the first n prime number." It's divided into 3 parts. 1st: This function will return true or false according to whether m is prime or composite. The array argument P will contain a sufficient number of primes to do the testing. Specifically, at the time isPrime() is called, array P must contain (at least) all primes p in the range 2 p m . For instance, to test m = 53 for primality, one must do successive trial divisions by 2, 3, 5, and 7. We go no further since 11 53 . Thus a precondition for the function call isPrime(53, P) is that P[0] = 2 , P[1] = 3 , P[2] = 5, and P[3] = 7 . The return value in this case would be true since all these divisions fail. Similarly to test m =143 , one must do trial divisions by 2, 3, 5, 7, and 11 (since 13 143 ). The precondition for the function call isPrime(143, P) is therefore P[0] = 2 , P[1] = 3 , P[2] = 5, P[3] = 7 , and P[4] =11. The return value in this case would be false since 11 divides 143. Function isPrime() should contain a loop that steps through array P, doing trial divisions. This loop should terminate when 2 either a trial division succeeds, in which case false is returned, or until the next prime in P is greater than m , in which case true is returned. Then there is the "main function" • Check that the user supplied exactly one command line argument which can be interpreted as a positive integer n. If the command line argument is not a single positive integer, your program will print a usage message as specified in the examples below, then exit. • Allocate array Primes[] of length n and initialize Primes[0] = 2 . • Enter a loop which will discover subsequent primes and store them as Primes[1] , Primes[2], Primes[3] , ……, Primes[n -1] . This loop should contain an inner loop which walks through successive integers and tests them for primality by calling function isPrime() with appropriate arguments. • Print the contents of array Primes[] to stdout, 10 to a line separated by single spaces. In other words Primes[0] through Primes[9] will go on line 1, Primes[10] though Primes[19] will go on line 2, and so on. Note that if n is not a multiple of 10, then the last line of output will contain fewer than 10 primes. The last function is called "usage" which I am not sure how to execute this! Your program will include a function called Usage() having signature static void Usage() that prints this message to stderr, then exits. Thus your program will contain three functions in all: main(), isPrime(), and Usage(). Each should be preceded by a comment block giving it’s name, a short description of it’s operation, and any necessary preconditions (such as those for isPrime().) And hear is my code, but I am having a bit of a problem and could you guys help me fix it? If I enter the number "5" it gives me the prime numbers which are "6,7,8,9" which doesn't make much sense. import java.util.; import java.io.; import java.lang.*; public class PrimeNumber { static boolean isPrime(int m, int[] P){ int squarert = Math.round( (float)Math.sqrt(m) ); int i = 2; boolean ans=false; while ((i<=squarert) & (ans==false)) { int c= P[i]; if (m%c==0) ans= true; else ans= false; i++; } /* if(ans ==true) ans=false; else ans=true; return ans; } ///****main public static void main(String[] args ) { Scanner in= new Scanner(System.in); int input= in.nextInt(); int i, j; int squarert; boolean ans = false; int userNum; int remander = 0; System.out.println("input: " + input); int[] prime = new int[input]; prime[0]= 2; for(i=1; i ans = isPrime(j,prime); j++;} prime[i] = j; } //prnt prime System.out.println("The first " + input + " prime number(s) are: "); for(int r=0; r }//end of main } Thanks for the help

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