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  • Date and Time Support in SQL Server 2008

    - by Aamir Hasan
      Using the New Date and Time Data Types Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} 1.       The new date and time data types in SQL Server 2008 offer increased range and precision and are ANSI SQL compatible. 2.       Separate date and time data types minimize storage space requirements for applications that need only date or time information. Moreover, the variable precision of the new time data type increases storage savings in exchange for reduced accuracy. 3.       The new data types are mostly compatible with the original date and time data types and use the same Transact-SQL functions. 4.       The datetimeoffset data type allows you to handle date and time information in global applications that use data that originates from different time zones. SELECT c.name, p.* FROM politics pJOIN country cON p.country = c.codeWHERE YEAR(Independence) < 1753ORDER BY IndependenceGO8.    Highlight the SELECT statement and click Execute ( ) to show the use of some of the date functions.T-SQLSELECT c.name AS [Country Name],        CONVERT(VARCHAR(12), p.Independence, 107) AS [Independence Date],       DATEDIFF(YEAR, p.Independence, GETDATE()) AS [Years Independent (appox)],       p.GovernmentFROM politics pJOIN country cON p.country = c.codeWHERE YEAR(Independence) < 1753ORDER BY IndependenceGO10.    Select the SET DATEFORMAT statement and click Execute ( ) to change the DATEFORMAT to day-month-year.T-SQLSET DATEFORMAT dmyGO11.    Select the DECLARE and SELECT statements and click Execute ( ) to show how the datetime and datetime2 data types interpret a date literal.T-SQLSET DATEFORMAT dmyDECLARE @dt datetime = '2008-12-05'DECLARE @dt2 datetime2 = '2008-12-05'SELECT MONTH(@dt) AS [Month-Datetime], DAY(@dt)     AS [Day-Datetime]SELECT MONTH(@dt2) AS [Month-Datetime2], DAY(@dt2)     AS [Day-Datetime2]GO12.    Highlight the DECLARE and SELECT statements and click Execute ( ) to use integer arithmetic on a datetime variable.T-SQLDECLARE @dt datetime = '2008-12-05'SELECT @dt + 1GO13.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how integer arithmetic is not allowed for datetime2 variables.T-SQLDECLARE @dt2 datetime = '2008-12-05'SELECT @dt2 + 1GO14.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how to use DATE functions to do simple arithmetic on datetime2 variables.T-SQLDECLARE @dt2 datetime2(7) = '2008-12-05'SELECT DATEADD(d, 1, @dt2)GO15.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how the GETDATE function can be used with both datetime and datetime2 data types.T-SQLDECLARE @dt datetime = GETDATE();DECLARE @dt2 datetime2(7) = GETDATE();SELECT @dt AS [GetDate-DateTime], @dt2 AS [GetDate-DateTime2]GO16.    Draw attention to the values returned for both columns and how they are equal.17.    Highlight the DECLARE and SELECT statements and click Execute ( ) to show how the SYSDATETIME function can be used with both datetime and datetime2 data types.T-SQLDECLARE @dt datetime = SYSDATETIME();DECLARE @dt2 datetime2(7) = SYSDATETIME();SELECT @dt AS [Sysdatetime-DateTime], @dt2     AS [Sysdatetime-DateTime2]GO18.    Draw attention to the values returned for both columns and how they are different.Programming Global Applications with DateTimeOffset 2.    If you have not previously created the SQLTrainingKitDB database while completing another demo in this training kit, highlight the CREATE DATABASE statement and click Execute ( ) to do so now.T-SQLCREATE DATABASE SQLTrainingKitDBGO3.    Select the USE and CREATE TABLE statements and click Execute ( ) to create table datetest in the SQLTrainingKitDB database.T-SQLUSE SQLTrainingKitDBGOCREATE TABLE datetest (  id integer IDENTITY PRIMARY KEY,  datetimecol datetimeoffset,  EnteredTZ varchar(40)); Reference:http://www.microsoft.com/downloads/details.aspx?FamilyID=E9C68E1B-1E0E-4299-B498-6AB3CA72A6D7&displaylang=en   

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  • Simplified INotifyPropertyChanged Implementation with WeakReference Support and Typed Property Acces

    - by Daniel Cazzulino
    I've grown a bit tired of implementing INotifyPropertyChanged. I've tried ways to improve it before (like this "ViewModel" custom tool which even generates strong-typed event accessors). But my fellow Clarius teammate Mariano thought it was overkill and didn't like that tool much. He mentioned an alternative approach also, which I didn't like too much because it relied on the consumer changing his typical interaction with the object events, but also because it has a substantial design flaw that causes handlers not to be called at all after a garbage collection happens. A very simple unit test will showcase this bug....Read full article

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  • SQL Server v.Next (Denali) : OS compatibility & upgrade support

    - by AaronBertrand
    Microsoft's Manageability PPM Dan Jones has asked for our feedback on their proposed list of supported operating systems and upgrade paths for the next version of SQL Server. (See the original post ). This has generated all kinds of spirited debates on twitter, in protected mailing lists, and in private e-mail. If you're going to be involved in moving to Denali, you should be aware of these proposals and stay on top of the discussion until the results are in. (The media are starting to pick up on...(read more)

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  • Differentiate procedural language(c) from oop languages(c++)

    - by niko
    I have been trying to differentiate c and c++(or oop languages) but I don't understand where the difference is. Note I have never used c++ but I asked my friends and some of them to differentiate c and c++ They say c++ has oop concepts and also the public, private modes for definition of variables and which c does not have though. Seriously I have done vb.net programming for a while 2 to 3 months, I never faced a situation to use class concepts and modes of definition like public and private. So I thought what could be the use for these? My friend explained me a program saying that if a variable is public, it can be accessed anywhere I said why not declare it as a global variable like in c? He did not get back to my question and he said if a variable is private it cannot be accessed by some other functions I said why not define it as a local variable, even these he was unable to answer. No matter where I read private variables cannot be accessed whereas public variables can be then why not make public as global and private as local whats the difference? whats the real use of public and private ? please don't say it can be used by everyone, I suppose why not we use some conditions and make the calls? I have heard people saying security reasons, a friend said if a function need to be accessed it should be inherited first. He explained saying that only admin should be able to have some rights and not all so that functions are made private and inherited only by the admin to use Then I said why not we use if condition if ( login == "admin") invoke the function he still did not answer these question. Please clear me with these things, I have done vb.net and vba and little c++ without using oop concepts because I never found their real use while I was writing the code, I'm a little afraid am I too back in oop concepts?

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  • PHP Browser Game Question - Pretty General Language Suitability and Approach Question

    - by JimBadger
    I'm developing a browser game, using PHP, but I'm unsure if the way I'm going about doing it is to be encouraged anymore. It's basically one of those MMOs where you level up various buildings and what have you, but, you then commit some abstract fighting entity that the game gives you, to an automated battle with another player (producing a textual, but hopefully amusing and varied combat report). Basically, as soon as two players agree to fight, PHP functions on the "fight.php" page run queries against a huge MySQL database, looking up all sorts of complicated fight moves and outcomes. There are about three hundred thousand combinations of combat stance, attack, move and defensive stances, so obviously this is quite a resource hungry process, and, on the super cheapo hosted server I'm using for development, it rapidly runs out of memory. The PHP script for the fight logic currently has about a thousand lines of code in it, and I'd say it's about half-finished as I try to add a bit of AI into the fight script. Is there a better way to do something this massive than simply having some functions in a PHP file calling the MySQL Database? I taught myself a modicum of PHP a while ago, and most of the stuff I read online (ages ago) about similar games was all PHP-based. but a) am I right to be using PHP at all, and b) am I missing some clever way of doing things that will somehow reduce server resource requirements? I'd consider non PHP alternatives but, if PHP is suitable, I'd rather stick to that, so there's no overhead of learning something new. I think I'd bite that bullet if it's the best option for a better game, though.

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  • Screenshot Tour: XBMC 11 Eden Rocks Improved iOS Support, AirPlay, and Even a Custom XBMC OS

    - by Jason Fitzpatrick
    XBMC, the wildly popular, free, and robust open-source media center suite, has a new version. XBMC 11 Eden is bursting with new features, improvements, and is even available as a stand-alone XBMC-centric OS. We’re big XBMC fans around here, so you’ll have to excuse us if we gush a little about how great the new XBMC 11 Eden release is. If you’re currently on XBMC 10, you’re in for quite a few treats with this upgrade. If you’ve never used XBMC before, well then, you’re in for a media center experience like you’ve never had one before. Here is what’s new in XBMC 11. How To Be Your Own Personal Clone Army (With a Little Photoshop) How To Properly Scan a Photograph (And Get An Even Better Image) The HTG Guide to Hiding Your Data in a TrueCrypt Hidden Volume

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  • Thinktecture.IdentityModel: WRAP and SWT Support

    - by Your DisplayName here!
    The latest drop of Thinktecture.IdentityModel contains some helpers for the Web Resource Authorization Protocol (WRAP) and Simple Web Tokens (SWT). WRAP The WrapClient class is a helper to request SWT tokens via WRAP. It supports issuer/key, SWT and SAML input credentials, e.g.: var client = new WrapClient(wrapEp); var swt = client.Issue(issuerName, issuerKey, scope); All Issue overrides return a SimpleWebToken type, which brings me to the next helper class. SWT The SimpleWebToken class wraps a SWT token. It combines a number of features: conversion between string format and CLR type representation creation of SWT tokens validation of SWT token projection of SWT token as IClaimsIdentity helpers to embed SWT token in headers and query strings The following sample code generates a SWT token using the helper class: private static string CreateSwtToken() {     var signingKey = "wA…";     var audience = "http://websample";     var issuer = "http://self";       var token = new SimpleWebToken(       issuer, audience, Convert.FromBase64String(signingKey));     token.AddClaim(ClaimTypes.Name, "dominick");     token.AddClaim(ClaimTypes.Role, "Users");     token.AddClaim(ClaimTypes.Role, "Administrators");     token.AddClaim("simple", "test");       return token.ToString(); }

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  • Fastest Functional Language

    - by Farouk
    I've recently been delving into functional programming especially Haskell and F#, the prior more so. After some googling around I could not find a benchmark comparison of the more prominent functional languages (Scala,F# etc). I know it's not necessarily fair to some of the languages (Scala comes to mind) given that they are hybrids, but I just wanna know which outperforms which on what operations and overall.

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  • Cross-language Extension Method Calling

    - by Tom Hines
    Extension methods are a concise way of binding functions to particular types. In my last post, I showed how Extension methods can be created in the .NET 2.0 environment. In this post, I discuss calling the extensions from other languages. Most of the differences I find between the Dot Net languages are mainly syntax.  The declaration of Extensions is no exception.  There is, however, a distinct difference with the framework accepting excensions made with C++ that differs from C# and VB.  When calling the C++ extension from C#, the compiler will SOMETIMES say there is no definition for DoCPP with the error: 'string' does not contain a definition for 'DoCPP' and no extension method 'DoCPP' accepting a first argument of type 'string' could be found (are you missing a using directive or an assembly reference?) If I recompile, the error goes away. The strangest problem with calling the C++ extension from C# is that I first must make SOME type of reference to the class BEFORE using the extension or it will not be recognized at all.  So, if I first call the DoCPP() as a static method, the extension works fine later.  If I make a dummy instantiation of the class, it works.  If I have no forward reference of the class, I get the same error as before and recompiling does not fix it.  It seems as if this none of this is supposed to work across the languages. I have made a few work-arounds to get the examples to compile and run. Note the following examples: Extension in C# using System; namespace Extension_CS {    public static class CExtension_CS    {  //in C#, the "this" keyword is the key.       public static void DoCS(this string str)       {          Console.WriteLine("CS\t{0:G}\tCS", str);       }    } } Extension in C++ /****************************************************************************\  * Here is the C++ implementation.  It is the least elegant and most quirky,  * but it works. \****************************************************************************/ #pragma once using namespace System; using namespace System::Runtime::CompilerServices;     //<-Essential // Reference: System.Core.dll //<- Essential namespace Extension_CPP {        public ref class CExtension_CPP        {        public:               [Extension] // or [ExtensionAttribute] /* either works */               static void DoCPP(String^ str)               {                      Console::WriteLine("C++\t{0:G}\tC++", str);               }        }; } Extension in VB ' Here is the VB implementation.  This is not as elegant as the C#, but it's ' functional. Imports System.Runtime.CompilerServices ' Public Module modExtension_VB 'Extension methods can be defined only in modules.    <Extension()> _       Public Sub DoVB(ByVal str As String)       Console.WriteLine("VB" & Chr(9) & "{0:G}" & Chr(9) & "VB", str)    End Sub End Module   Calling program in C# /******************************************************************************\  * Main calling program  * Intellisense and VS2008 complain about the CPP implementation, but with a  * little duct-tape, it works just fine. \******************************************************************************/ using System; using Extension_CPP; using Extension_CS; using Extension_VB; // vitual namespace namespace TestExtensions {    public static class CTestExtensions    {       /**********************************************************************\        * For some reason, this needs a direct reference into the C++ version        * even though it does nothing than add a null reference.        * The constructor provides the fake usage to please the compiler.       \**********************************************************************/       private static CExtension_CPP x = null;   // <-DUCT_TAPE!       static CTestExtensions()       {          // Fake usage to stop compiler from complaining          if (null != x) {} // <-DUCT_TAPE       }       static void Main(string[] args)       {          string strData = "from C#";          strData.DoCPP();          strData.DoCS();          strData.DoVB();       }    } }   Calling program in VB  Imports Extension_CPP Imports Extension_CS Imports Extension_VB Imports System.Runtime.CompilerServices Module TestExtensions_VB    <Extension()> _       Public Sub DoCPP(ByVal str As String)       'Framework does not treat this as an extension, so use the static       CExtension_CPP.DoCPP(str)    End Sub    Sub Main()       Dim strData As String = "from VB"       strData.DoCS()       strData.DoVB()       strData.DoCPP() 'fake    End Sub End Module  Calling program in C++ // TestExtensions_CPP.cpp : main project file. #include "stdafx.h" using namespace System; using namespace Extension_CPP; using namespace Extension_CS; using namespace Extension_VB; void main(void) {        /*******************************************************\         * Extension methods are called like static methods         * when called from C++.  There may be a difference in         * syntax when calling the VB extension as VB Extensions         * are embedded in Modules instead of classes        \*******************************************************/     String^ strData = "from C++";     CExtension_CPP::DoCPP(strData);     CExtension_CS::DoCS(strData);     modExtension_VB::DoVB(strData); //since Extensions go in Modules }

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  • Mobile Linux Gets Support From Chip Vendors

    <b>Hardware Central:</b> "The development of Linux on mobile devices may be poised to get a boost thanks to the formation of a new industry group called Linaro, backed by a consortium of chip vendors including ARM, Freescale, Texas Instruments, Samsung and ST-Ericsson."

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  • TRADACOMS Support in B2B

    - by Dheeraj Kumar
    TRADACOMS is an initial standard for EDI. Predominantly used in the retail sector of United Kingdom. This is similar to EDIFACT messaging system, involving ecs file for translation and validation of messages. The slight difference between EDIFACT and TRADACOMS is, 1. TRADACOMS is a simpler version than EDIFACT 2. There is no Functional Acknowledgment in TRADACOMS 3. Since it is just a business message to be sent to the trading partner, the various reference numbers at STX, BAT, MHD level need not be persisted in B2B as there is no Business logic gets derived out of this. Considering this, in AS11 B2B, this can be handled out of the box using Positional Flat file document plugin. Since STX, BAT segments which define the envelope details , and part of transaction, has to be sent from the back end application itself as there is no Document protocol parameters defined in B2B. These would include some of the identifiers like SenderCode, SenderName, RecipientCode, RecipientName, reference numbers. Additionally the batching in this case be achieved by sending all the messages of a batch in a single xml from backend application, containing total number of messages in Batch as part of EOB (Batch trailer )segment. In the case of inbound scenario, we can identify the document based on start position and end position of the incoming document. However, there is a plan to identify the incoming document based on Tradacom standard instead of start/end position. Please email to [email protected] if you need a working sample.

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  • OEPE with ADF binding support available: Total Eclipse

    - by Frank Nimphius
    The current release of Oracle Enterprise Pack for Eclipse, though in technology preview, brings Oracle ADF binding to the Eclipse IDE. You can download the Software from the link below: Oracle Enterprise Pack for Eclipse (12.1.1.1.0) Technical Preview New June 2012 Certified on Windows 7/XP/Vista, MacOS, and Linux. Supported on JDK 6. For many Eclipse users, ADF is new and therefore I expect them to need guidance and help in case they run into issues they don't know how to recover from. Similar, ADF users familiar with Oracle JDeveloper that want to give OEPE a try, will find things different in Eclipse and thus may have questions.  For both audiences I suggest to post issues to the OEPE forum on the Oracle Technology Network: I'll extend my OTN monitoring to include the OEPE forum on a daily basis to learn about developer needs, requirements and - of course - to catch bugs that need to be filed. From my side this is a part-time involvement, which means that the more ADF questions show on the forum, the more help I could need in answering them. The OTN forum for JDeveloper in my opnion wouldn't be the right place to go to unless the question is a generic ADF question that is not dependent on the integration in Eclipse. Here's the OEPE forum link for a start https://forums.oracle.com/forums/forum.jspa?forumID=578 Frank

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  • Looking for Windows shared web hosting with PHP support

    - by Ladislav Mrnka
    I'm looking for Windows based shared web hosting which supports multiple hosted web sites (multiple domains). Supported technologies should contain: ASP.NET 4, ASP.NET MVC IIS 7 MS SQL 2008 PHP, MySQL It is for my hobby projects so it should not be too expensive. I tried GoDaddy's Windows Deluxe hosting but the experience is very bad and I want to move elsewhere. WordPress hosted on GoDaddy's Windows hosting is unloaded every few minutes and next request takes around 20s to complete. Following request to empty site takes around 3s to complete. Even request for RSS wich transfers 1.2KB takes several seconds. The delay happens in PHP processing because static content is served within 200ms. It helped to migrate to Linux hosting (all requests are served under 1s) but Linux hosting is not what I'm looking for.

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  • Codifying a natural language requirements spec

    - by ProfK
    I have a fairly technical functionality requirements spec, expressed in English prose, produced by my project manager. It is structured as a collection of UI tabs, where the requirements for each tab are expressed as a lit of UI fields and a list of business rules for the tab. Most business rules are for UI fields on a tab, e.g: a) Must be alphanumeric, max length 20. b) Must be a dropdown, with values from table x. c) Is mandatory. d) Is mandatory under certain conditions, e.g. another field is just populated, or has a specific value. Then other business rules get a little more complex. The spec is for a job application, so the central business object (table) is the Applicant, and we have several other tables with one-to-many relationships with applicant, such as Degree, HighSchool, PreviousEmployer, Diploma, etc. e) One such complex rule says a status field can only be assigned a certain value if a many-side record exists in at least one of the many-side tables. E.g. the Applicant has at least one HighSchool or at least one Diploma record. I am looking for advice on how to codify these requirements into a more structured specification defined in terms of tables, fields, and relationships, especially for the conditional rules for fields and for the presence of related records. Any suggestions and advice will be most welcome, but I would be overjoyed if i could find an already defined system or structure for expressing things like this.

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  • Suggestions for a CMS markup language for PHP

    - by Yanick Rochon
    As a learning experience, and as project, I am attempting to write a CMS module for ZF2. One of the functionality I would like to have is the possibility of adding dynamic contents in the pages by calling PHP functions in the view scripts. However, I do not want to give the users freedom in writing PHP code directly inside the page content, but rather implement custom view helpers (or widgets) to handle logic. For example: calling partial, partialLoop, url, etc. specifying arguments and all. I liked the idea of extending Markdown but this would get complicated when trying to add custom CSS class to elements, etc. Then I had the idea of simply doing a preg_replace on some patterns. For example, the string : ### partialLoop:['partials/display.phtml',[{id:'p1',price:4.99},{id:'p2',price:12.34}]] ### would be replaced by <?php echo $this->partialLoop('partials/display.phtml', array(array('id'=>'p1','price'=>4.99),array('id'=>'p2','price'=>12.34))) ?> Obviously, there would be some caching done so the page content is not rendered everytime. Does this sound good? If not, what would be a good way of doing this? Or is there a project already being developed for doing this? (I'd like to avoid heavy third party libs and something fairly or fully compatible with ZF2 would be nice.) Thanks.

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  • Support same url in different forms

    - by Vikas Gulati
    I have seen many websites supporting multiple forms of the same URL. For example consider www.example.com/question1/ OR www.example.com/Question1/ OR www.example.com/QUESTION1/ etc. all lead to one page with say <link rel="canonical" href="http://www.example.com/question1/" > or a 301 redirect to www.example.com/question1/. Does this affect the page rank anyhow or its just for seemless user experience or there is some other reason behind this? Infact even stackoverflow/stackexchange does this. No matter what the text after the id of the question in url they redirect you to the correct question!

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  • Java Script Support In ADF

    - by Vijay Mohan
    1. if you want the java script code in jspx.   - <af:resource> tag available under adf faces ui component has the best supportability for java script. If you want to invoke the js function on some adf ui component then you will have to include a client listener tag with js function name and the event type.If you want it to happen on a non adf html based compoent then you can have an anchor tag  specified with the javascript tag , event type and js function name (with parameters - if any) and as soon as the specifed action happens on that component then the js function would be invoked.2.if you want it in adf page fragment (jsff)  - jsff supports java script wrapped under <trh:script> </trh:script> tag. Rest of the things follow the same way as that of jspx.

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  • What to do if I am working on a language that I don't like

    - by Sayem Ahmed
    Hi there, I really don't know if this is the right place to ask this question, but if it isn't, then I guess someone will notify. Anyway, I am working in a software development farm which is currently using PowerBuilder to develop a mid-size ERP solution. The work environment and company management are so great that it may be the best in the whole Bangladesh. Only problem is the technology that are currently being used, which is this PowerBuilder. Now I am a guy who tends to prefer modern development technologies, like DI containers, ORM, TDD, JQuery etc. PowerBuilder is a great tool too, but I couldn' like the application techniques used to build PB applications. These techniques are so inheritance-dependent that many a times these create a great deal of sufferings. I remember two days ago I had to change some processing logic in a core user object and as a result I had to test and re-test all the forms that the application have(apparently, there are almost 20 forms there, each of them with 3-4 kinds of functionalities). Also, learning PB is tough, because online material on this thing is very, very low. I can't afford to read all the documentation that PB provide because I have hard deadlines on the work that I have to do. Another thing with PB is that applications tend to rely on business logic that are implemented on databases which causes debugging to be a nightmare. As a result, I don't feel motivated enough to work in this IDE/System/Framework (or whatever) anymore. My productivity has greatly decreased, and I am not delivering quality code. I think I have the following options available to me - Remain in the current job, keep delivering worse code and let my productivity decrease day by day, taking salaries and bonuses but not delivering quality codes/doing my job the way I should, Search for a new job. At this point number 2 seems a good option, but there are also some issues. As I mentioned before, our management may be the best in the country. Our company owner is himself a software developer with 24 years of experience in software development. He is currently our Team Leader and System Analyst. He is by far the greatest manager and boss I have ever seen. He understands developer's mentality very well(as he IS himself a developer). He is also a great, kind and generous guy. Our company is only a start-up company with 10 developers. Among them, only 3-4 people knows about the business logic behind the ERP, and I am one of them. If I switch my current job, it may hamper the development of this product which I really don't want. I couldn't decide what to do in this situation, so I turned to the community for advice.

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  • Extreme Optimization – Numerical Algorithm Support

    - by JoshReuben
    Function Delegates Many calculations involve the repeated evaluation of one or more user-supplied functions eg Numerical integration. The EO MathLib provides delegate types for common function signatures and the FunctionFactory class can generate new delegates from existing ones. RealFunction delegate - takes one Double parameter – can encapsulate most of the static methods of the System.Math class, as well as the classes in the Extreme.Mathematics.SpecialFunctions namespace: var sin = new RealFunction(Math.Sin); var result = sin(1); BivariateRealFunction delegate - takes two Double parameters: var atan2 = new BivariateRealFunction (Math.Atan2); var result = atan2(1, 2); TrivariateRealFunction delegate – represents a function takes three Double arguments ParameterizedRealFunction delegate - represents a function taking one Integer and one Double argument that returns a real number. The Pow method implements such a function, but the arguments need order re-arrangement: static double Power(int exponent, double x) { return ElementaryFunctions.Pow(x, exponent); } ... var power = new ParameterizedRealFunction(Power); var result = power(6, 3.2); A ComplexFunction delegate - represents a function that takes an Extreme.Mathematics.DoubleComplex argument and also returns a complex number. MultivariateRealFunction delegate - represents a function that takes an Extreme.Mathematics.LinearAlgebra.Vector argument and returns a real number. MultivariateVectorFunction delegate - represents a function that takes a Vector argument and returns a Vector. FastMultivariateVectorFunction delegate - represents a function that takes an input Vector argument and an output Matrix argument – avoiding object construction  The FunctionFactory class RealFromBivariateRealFunction and RealFromParameterizedRealFunction helper methods - transform BivariateRealFunction or a ParameterizedRealFunction into a RealFunction delegate by fixing one of the arguments, and treating this as a new function of a single argument. var tenthPower = FunctionFactory.RealFromParameterizedRealFunction(power, 10); var result = tenthPower(x); Note: There is no direct way to do this programmatically in C# - in F# you have partial value functions where you supply a subset of the arguments (as a travelling closure) that the function expects. When you omit arguments, F# generates a new function that holds onto/remembers the arguments you passed in and "waits" for the other parameters to be supplied. let sumVals x y = x + y     let sumX = sumVals 10     // Note: no 2nd param supplied.     // sumX is a new function generated from partially applied sumVals.     // ie "sumX is a partial application of sumVals." let sum = sumX 20     // Invokes sumX, passing in expected int (parameter y from original)  val sumVals : int -> int -> int val sumX : (int -> int) val sum : int = 30 RealFunctionsToVectorFunction and RealFunctionsToFastVectorFunction helper methods - combines an array of delegates returning a real number or a vector into vector or matrix functions. The resulting vector function returns a vector whose components are the function values of the delegates in the array. var funcVector = FunctionFactory.RealFunctionsToVectorFunction(     new MultivariateRealFunction(myFunc1),     new MultivariateRealFunction(myFunc2));  The IterativeAlgorithm<T> abstract base class Iterative algorithms are common in numerical computing - a method is executed repeatedly until a certain condition is reached, approximating the result of a calculation with increasing accuracy until a certain threshold is reached. If the desired accuracy is achieved, the algorithm is said to converge. This base class is derived by many classes in the Extreme.Mathematics.EquationSolvers and Extreme.Mathematics.Optimization namespaces, as well as the ManagedIterativeAlgorithm class which contains a driver method that manages the iteration process.  The ConvergenceTest abstract base class This class is used to specify algorithm Termination , convergence and results - calculates an estimate for the error, and signals termination of the algorithm when the error is below a specified tolerance. Termination Criteria - specify the success condition as the difference between some quantity and its actual value is within a certain tolerance – 2 ways: absolute error - difference between the result and the actual value. relative error is the difference between the result and the actual value relative to the size of the result. Tolerance property - specify trade-off between accuracy and execution time. The lower the tolerance, the longer it will take for the algorithm to obtain a result within that tolerance. Most algorithms in the EO NumLib have a default value of MachineConstants.SqrtEpsilon - gives slightly less than 8 digits of accuracy. ConvergenceCriterion property - specify under what condition the algorithm is assumed to converge. Using the ConvergenceCriterion enum: WithinAbsoluteTolerance / WithinRelativeTolerance / WithinAnyTolerance / NumberOfIterations Active property - selectively ignore certain convergence tests Error property - returns the estimated error after a run MaxIterations / MaxEvaluations properties - Other Termination Criteria - If the algorithm cannot achieve the desired accuracy, the algorithm still has to end – according to an absolute boundary. Status property - indicates how the algorithm terminated - the AlgorithmStatus enum values:NoResult / Busy / Converged (ended normally - The desired accuracy has been achieved) / IterationLimitExceeded / EvaluationLimitExceeded / RoundOffError / BadFunction / Divergent / ConvergedToFalseSolution. After the iteration terminates, the Status should be inspected to verify that the algorithm terminated normally. Alternatively, you can set the ThrowExceptionOnFailure to true. Result property - returns the result of the algorithm. This property contains the best available estimate, even if the desired accuracy was not obtained. IterationsNeeded / EvaluationsNeeded properties - returns the number of iterations required to obtain the result, number of function evaluations.  Concrete Types of Convergence Test classes SimpleConvergenceTest class - test if a value is close to zero or very small compared to another value. VectorConvergenceTest class - test convergence of vectors. This class has two additional properties. The Norm property specifies which norm is to be used when calculating the size of the vector - the VectorConvergenceNorm enum values: EuclidianNorm / Maximum / SumOfAbsoluteValues. The ErrorMeasure property specifies how the error is to be measured – VectorConvergenceErrorMeasure enum values: Norm / Componentwise ConvergenceTestCollection class - represent a combination of tests. The Quantifier property is a ConvergenceTestQuantifier enum that specifies how the tests in the collection are to be combined: Any / All  The AlgorithmHelper Class inherits from IterativeAlgorithm<T> and exposes two methods for convergence testing. IsValueWithinTolerance<T> method - determines whether a value is close to another value to within an algorithm's requested tolerance. IsIntervalWithinTolerance<T> method - determines whether an interval is within an algorithm's requested tolerance.

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