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  • Weird problem with keyboard

    - by Click Upvote
    I have a wireless bluetooth keyboard. Suddenly, something weird has started happening to it. If I press most of the alphabetic keys nothing happens, but some of the keys have gotten substituted for one another. For example if I press 'tab', its as if i hit 'enter', if I press 'enter' on num pad, it functions as tab. If i press 's' it functions as the right click menu button, and pressing the right click menu button functions as 's'. Ctrl and ALT buttons and the button that opens the start menu seem to be working as normal. The normal laptop keyboard is working fine, and the wireless mouse that came with the keyboard is also working fine, however the keyboard is what's messing up. Does anyone know what the prob is? I'm using Windows XP and 'Microsoft Intelli Keyboard' and mouse.

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  • PHP Requests Being Blocked After Making About 25 in Ten Minutes

    - by Daniel Stern
    We have an administrative portal where we run PHP functions through a Javascript portal using ajax for administrative purposes. For example, we might have a function called updateAllDatabaseEntries() which would call AJAX functions in rapid succession, with those functions each executing numerous SQL queries. The problem is after making several successive requests from the same computer (not an excessive amount, maybe 30 in ten minutes) the system will stop responding to any PHP, HTTP requests ETC ONLY from my computer. From other computers in the office the panel can still be accessed, and access is restored to this computer after about 15 minutes. We believe this is not a glitch but some kind of security feature built into our server, possibly relating to Suhosin and likely well-intentioned but currently preventing us from running our system administration. Server Info: Linux 2.6.32-5-xen-amd64 #1 SMP Tue Mar 8 00:01:30 UTC 2011 x86_64 GNU/Linux Cheers - DS

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  • How to generate a Program template by generating an abstract class

    - by Byron-Lim Timothy Steffan
    i have the following problem. The 1st step is to implement a program, which follows a specific protocol on startup. Therefore, functions as onInit, onConfigRequest, etc. will be necessary. (These are triggered e.g. by incoming message on a TCP Port) My goal is to generate a class for example abstract one, which has abstract functions as onInit(), etc. A programmer should just inherit from this base class and should merely override these abstract functions of the base class. The rest as of the protocol e.g. should be simply handled in the background (using the code of the base class) and should not need to appear in the programmers code. What is the correct design strategy for such tasks? and how do I deal with, that the static main method is not inheritable? What are the key-tags for this problem? (I have problem searching for a solution since I lack clear statements on this problem) Goal is to create some sort of library/class, which - included in ones code - results in executables following the protocol. EDIT (new explanation): Okay let me try to explain more detailled: In this case programs should be clients within a client server architecture. We have a client server connection via TCP/IP. Each program needs to follow a specific protocol upon program start: As soon as my program starts and gets connected to the server it will receive an Init Message (TcpClient), when this happens it should trigger the function onInit(). (Should this be implemented by an event system?) After onInit() a acknowledgement message should be sent to the server. Afterwards there are some other steps as e.g. a config message from the server which triggers an onConfig and so on. Let's concentrate on the onInit function. The idea is, that onInit (and onConfig and so on) should be the only functions the programmer should edit while the overall protocol messaging is hidden for him. Therefore, I thought using an abstract class with the abstract methods onInit(), onConfig() in it should be the right thing. The static Main class I would like to hide, since within it e.g. there will be some part which connects to the tcp port, which reacts on the Init Message and which will call the onInit function. 2 problems here: 1. the static main class cant be inherited, isn it? 2. I cannot call abstract functions from the main class in the abstract master class. Let me give an Pseudo-example for my ideas: public abstract class MasterClass { static void Main(string[] args){ 1. open TCP connection 2. waiting for Init Message from server 3. onInit(); 4. Send Acknowledgement, that Init Routine has ended successfully 5. waiting for Config message from server 6..... } public abstract void onInit(); public abstract void onConfig(); } I hope you get the idea now! The programmer should afterwards inherit from this masterclass and merely need to edit the functions onInit and so on. Is this way possible? How? What else do you recommend for solving this? EDIT: The strategy ideo provided below is a good one! Check out my comment on that.

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  • Defend PHP; convince me it isn't horrible

    - by Jason L
    I made a tongue-in-cheek comment in another question thread calling PHP a terrible language and it got down-voted like crazy. Apparently there are lots of people here who love PHP. So I'm genuinely curious. What am I missing? What makes PHP a good language? Here are my reasons for disliking it: PHP has inconsistent naming of built-in and library functions. Predictable naming patterns are important in any design. PHP has inconsistent parameter ordering of built-in functions, eg array_map vs. array_filter which is annoying in the simple cases and raises all sorts of unexpected behaviour or worse. The PHP developers constantly deprecate built-in functions and lower-level functionality. A good example is when they deprecated pass-by-reference for functions. This created a nightmare for anyone doing, say, function callbacks. A lack of consideration in redesign. The above deprecation eliminated the ability to, in many cases, provide default keyword values for functions. They fixed this in PHP 5, but they deprecated the pass-by-reference in PHP 4! Poor execution of name spaces (formerly no name spaces at all). Now that name spaces exist, what do we use as the dereference character? Backslash! The character used universally for escaping, even in PHP! Overly-broad implicit type conversion leads to bugs. I have no problem with implicit conversions of, say, float to integer or back again. But PHP (last I checked) will happily attempt to magically convert an array to an integer. Poor recursion performance. Recursion is a fundamentally important tool for writing in any language; it can make complex algorithms far simpler. Poor support is inexcusable. Functions are case insensitive. I have no idea what they were thinking on this one. A programming language is a way to specify behavior to both a computer and a reader of the code without ambiguity. Case insensitivity introduces much ambiguity. PHP encourages (practically requires) a coupling of processing with presentation. Yes, you can write PHP that doesn't do so, but it's actually easier to write code in the incorrect (from a sound design perspective) manner. PHP performance is abysmal without caching. Does anyone sell a commercial caching product for PHP? Oh, look, the designers of PHP do. Worst of all, PHP convinces people that designing web applications is easy. And it does indeed make much of the effort involved much easier. But the fact is, designing a web application that is both secure and efficient is a very difficult task. By convincing so many to take up programming, PHP has taught an entire subgroup of programmers bad habits and bad design. It's given them access to capabilities that they lack the understanding to use safely. This has led to PHP's reputation as being insecure. (However, I will readily admit that PHP is no more or less secure than any other web programming language.) What is it that I'm missing about PHP? I'm seeing an organically-grown, poorly-managed mess of a language that's spawning poor programmers. So convince me otherwise!

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  • Real Excel Templates I

    - by Tim Dexter
    As promised, I'm starting to document the new Excel templates that I teased you all with a few weeks back. Leslie is buried in 11g documentation and will not get to officially documenting the templates for a while. I'll do my best to be professional and not ramble on about this and that, although the weather here has finally turned and its 'scorchio' here in Colorado today. Maybe our stand of Aspen will finally come into leaf ... but I digress. Preamble These templates are not actually that new, I helped in a small way to develop them a few years back with Excel 'meistress' Shirley for a company that was trying to use the Report Manager(RR) Excel FSG outputs under EBS 12. The functionality they needed was just not there in the RR FSG templates, the templates are actually XSL that is created from the the RR Excel template builder and fed to BIP for processing. Think of Excel from our RTF templates and you'll be there ie not really Excel but HTML masquerading as Excel. Although still under controlled release in EBS they have now made their way to the standlone release and are willing to share their Excel goodness. You get everything you have with hte Excel Analyzer Excel templates plus so much more. Therein lies a question, what will happen to the Analyzer templates? My understanding is that both will come together into a single Excel template format some time in the post-11g release world. The new XLSX format for Exce 2007/10 is also in the mix too so watch this space. What more do these templates offer? Well, you can structure data in the Excel output. Similar to RTF templates you can create sheets of data that have master-detail n relationships. Although the analyzer templates can do this, you have to get into macros whereas BIP will do this all for you. You can also use native XSL functions in your data to manipulate it prior to rendering. BP functions are not currently supported. The most impressive, for me at least, is the sheet 'bursting'. You can split your hierarchical data across multiple sheets and dynamically name those sheets. Finally, you of course, still get all the native Excel functionality. Pre-reqs You must be on 10.1.3.4.1 plus the latest rollup patch, 9546699. You can patch upa BIP instance running with OBIEE, no problem You need Excel 2000 or above to build the templates Some patience - there is no Excel template builder for these new templates. So its all going to have to be done by hand. Its not that tough but can get a little 'fiddly'. You can not test the template from Excel , it has to be deployed and then run. Limitations The new templates are definitely superior to the Analyzer templates but there are a few limitations. Re-grouping is not supported. You can only follow a data hierarchy not bend it to your will unless you want to get into macros. No support for BIP functions. The templates support native XSL functions only. No template builder Getting Started The templates make the use of named cells and groups of cells to allow BIP to find the insertion point for data points. It also uses a hidden sheet to store calculation mappings from named cells to XML data elements. To start with, in the great BIP tradition, we need some sample XML data. Becasue I wanted to show the master-detail output we need some hierarchical data. If you have not yet gotten into the data templates, now is a good time, I wrote a post a while back starting from the simple to more complex. They generate ideal data sets for these templates. Im working with the following data set: <EMPLOYEES> <LIST_G_DEPT> <G_DEPT> <DEPARTMENT_ID>10</DEPARTMENT_ID> <DEPARTMENT_NAME>Administration</DEPARTMENT_NAME> <LIST_G_EMP> <G_EMP> <EMPLOYEE_ID>200</EMPLOYEE_ID> <EMP_NAME>Jennifer Whalen</EMP_NAME> <EMAIL>JWHALEN</EMAIL> <PHONE_NUMBER>515.123.4444</PHONE_NUMBER> <HIRE_DATE>1987-09-17T00:00:00.000-06:00</HIRE_DATE> <SALARY>4400</SALARY> </G_EMP> </LIST_G_EMP> <TOTAL_EMPS>1</TOTAL_EMPS> <TOTAL_SALARY>4400</TOTAL_SALARY> <AVG_SALARY>4400</AVG_SALARY> <MAX_SALARY>4400</MAX_SALARY> <MIN_SALARY>4400</MIN_SALARY> </G_DEPT> ... <LIST_G_DEPT> <EMPLOYEES> Simple enough to follow and bread and butter stuff for an RTF template. Building the Template For an Excel template we need to start by thinking about how we want to render the data. Come up with a sample output in Excel. Its all dummy data, nothing marked up yet with one row of data for each level. I have the department name and then a repeating row for the employees. You can apply Excel formatting to the layout. The total is going to be derived from a data element. We'll get to Excel functions later. Marking Up Cells Next we need to start marking up the cells with custom names to map them to data elements. The cell names need to follow a specific format: For data grouping, XDO_GROUP_?group_name? For data elements, XDO_?element_name? Notice the question mark delimter, the group_name and element_name are case sensitive. The next step is to find how to name cells; the easiest method is to highlight the cell and then type in the name. You can also find the Name Manager dialog. I use 2007 and its available on the ribbon under the Formulas section Go thorugh the process of naming all the cells for the element values you have. Using my data set from above.You should end up with something like this in your 'Name Manager' dialog. You can update any mistakes you might have made through this dialog. Creating Groups In the image above you can see there are a couple of named group cells. To create these its a simple case of highlighting the cells that make up the group and then naming them. For the EMP group, highlight the employee row and then type in the name, XDO_GROUP?G_EMP? Notice the 10,000 total is outside of the G_EMP group. Its actually named, XDO_?TOTAL_SALARY?, a query calculated value. For the department group, we need to include the department name cell and the sub EMP grouping and name it, XDO_GROUP?G_DEPT? Notice, the 10,000 total is included in the G_DEPT group. This will ensure it repeats at the department level. Lastly, we do need to include a special sheet in the workbook. We will not have anything meaningful in there for now, but it needs to be present. Create a new sheet and name it XDO_METADATA. The name is important as the BIP rendering engine will looking for it. For our current example we do not need anything other than the required stuff in our XDO_METADATA sheet but, it must be present. Easy enough to hide it. Here's what I have: The only cell that is important is the 'Data Constraints:' cell. The rest is optional. To save curious users getting distracted, hide the metadata sheet. Deploying & Running Templates We should now have a usable Excel template. Loading it into a report is easy enough using the browser UI, just like an RTF template. Set the template type to Excel. You will now be able to run the report and hopefully get something like this. You will not get the red highlighting, thats just some conditional formatting I added to the template using Excel functionality. Your dates are probably going to look raw too. I got around this for now using an Excel function on the cell: =--REPLACE(SUBSTITUTE(E8,"T"," "),LEN(E8)-6,6,"") Google to the rescue on that one. Try some other stuff out. To avoid constantly loading the template through the UI. If you have BIP running locally or you can access the reports repository, once you have loaded the template the first time. Just save the template directly into the report folder. I have put together a sample report using a sample data set, available here. Just drop the xml data file, EmpbyDeptExcelData.xml into 'demo files' folder and you should be good to go. Thats the basics, next we'll start using some XSL functions in the template and move onto the 'bursting' across sheets.

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  • Metro: Namespaces and Modules

    - by Stephen.Walther
    The goal of this blog entry is to describe how you can use the Windows JavaScript (WinJS) library to create namespaces. In particular, you learn how to use the WinJS.Namespace.define() and WinJS.Namespace.defineWithParent() methods. You also learn how to hide private methods by using the module pattern. Why Do We Need Namespaces? Before we do anything else, we should start by answering the question: Why do we need namespaces? What function do they serve? Do they just add needless complexity to our Metro applications? After all, plenty of JavaScript libraries do just fine without introducing support for namespaces. For example, jQuery has no support for namespaces and jQuery is the most popular JavaScript library in the universe. If jQuery can do without namespaces, why do we need to worry about namespaces at all? Namespaces perform two functions in a programming language. First, namespaces prevent naming collisions. In other words, namespaces enable you to create more than one object with the same name without conflict. For example, imagine that two companies – company A and company B – both want to make a JavaScript shopping cart control and both companies want to name the control ShoppingCart. By creating a CompanyA namespace and CompanyB namespace, both companies can create a ShoppingCart control: a CompanyA.ShoppingCart and a CompanyB.ShoppingCart control. The second function of a namespace is organization. Namespaces are used to group related functionality even when the functionality is defined in different physical files. For example, I know that all of the methods in the WinJS library related to working with classes can be found in the WinJS.Class namespace. Namespaces make it easier to understand the functionality available in a library. If you are building a simple JavaScript application then you won’t have much reason to care about namespaces. If you need to use multiple libraries written by different people then namespaces become very important. Using WinJS.Namespace.define() In the WinJS library, the most basic method of creating a namespace is to use the WinJS.Namespace.define() method. This method enables you to declare a namespace (of arbitrary depth). The WinJS.Namespace.define() method has the following parameters: · name – A string representing the name of the new namespace. You can add nested namespace by using dot notation · members – An optional collection of objects to add to the new namespace For example, the following code sample declares two new namespaces named CompanyA and CompanyB.Controls. Both namespaces contain a ShoppingCart object which has a checkout() method: // Create CompanyA namespace with ShoppingCart WinJS.Namespace.define("CompanyA"); CompanyA.ShoppingCart = { checkout: function (){ return "Checking out from A"; } }; // Create CompanyB.Controls namespace with ShoppingCart WinJS.Namespace.define( "CompanyB.Controls", { ShoppingCart: { checkout: function(){ return "Checking out from B"; } } } ); // Call CompanyA ShoppingCart checkout method console.log(CompanyA.ShoppingCart.checkout()); // Writes "Checking out from A" // Call CompanyB.Controls checkout method console.log(CompanyB.Controls.ShoppingCart.checkout()); // Writes "Checking out from B" In the code above, the CompanyA namespace is created by calling WinJS.Namespace.define(“CompanyA”). Next, the ShoppingCart is added to this namespace. The namespace is defined and an object is added to the namespace in separate lines of code. A different approach is taken in the case of the CompanyB.Controls namespace. The namespace is created and the ShoppingCart object is added to the namespace with the following single line of code: WinJS.Namespace.define( "CompanyB.Controls", { ShoppingCart: { checkout: function(){ return "Checking out from B"; } } } ); Notice that CompanyB.Controls is a nested namespace. The top level namespace CompanyB contains the namespace Controls. You can declare a nested namespace using dot notation and the WinJS library handles the details of creating one namespace within the other. After the namespaces have been defined, you can use either of the two shopping cart controls. You call CompanyA.ShoppingCart.checkout() or you can call CompanyB.Controls.ShoppingCart.checkout(). Using WinJS.Namespace.defineWithParent() The WinJS.Namespace.defineWithParent() method is similar to the WinJS.Namespace.define() method. Both methods enable you to define a new namespace. The difference is that the defineWithParent() method enables you to add a new namespace to an existing namespace. The WinJS.Namespace.defineWithParent() method has the following parameters: · parentNamespace – An object which represents a parent namespace · name – A string representing the new namespace to add to the parent namespace · members – An optional collection of objects to add to the new namespace The following code sample demonstrates how you can create a root namespace named CompanyA and add a Controls child namespace to the CompanyA parent namespace: WinJS.Namespace.define("CompanyA"); WinJS.Namespace.defineWithParent(CompanyA, "Controls", { ShoppingCart: { checkout: function () { return "Checking out"; } } } ); console.log(CompanyA.Controls.ShoppingCart.checkout()); // Writes "Checking out" One significant advantage of using the defineWithParent() method over the define() method is the defineWithParent() method is strongly-typed. In other words, you use an object to represent the base namespace instead of a string. If you misspell the name of the object (CompnyA) then you get a runtime error. Using the Module Pattern When you are building a JavaScript library, you want to be able to create both public and private methods. Some methods, the public methods, are intended to be used by consumers of your JavaScript library. The public methods act as your library’s public API. Other methods, the private methods, are not intended for public consumption. Instead, these methods are internal methods required to get the library to function. You don’t want people calling these internal methods because you might need to change them in the future. JavaScript does not support access modifiers. You can’t mark an object or method as public or private. Anyone gets to call any method and anyone gets to interact with any object. The only mechanism for encapsulating (hiding) methods and objects in JavaScript is to take advantage of functions. In JavaScript, a function determines variable scope. A JavaScript variable either has global scope – it is available everywhere – or it has function scope – it is available only within a function. If you want to hide an object or method then you need to place it within a function. For example, the following code contains a function named doSomething() which contains a nested function named doSomethingElse(): function doSomething() { console.log("doSomething"); function doSomethingElse() { console.log("doSomethingElse"); } } doSomething(); // Writes "doSomething" doSomethingElse(); // Throws ReferenceError You can call doSomethingElse() only within the doSomething() function. The doSomethingElse() function is encapsulated in the doSomething() function. The WinJS library takes advantage of function encapsulation to hide all of its internal methods. All of the WinJS methods are defined within self-executing anonymous functions. Everything is hidden by default. Public methods are exposed by explicitly adding the public methods to namespaces defined in the global scope. Imagine, for example, that I want a small library of utility methods. I want to create a method for calculating sales tax and a method for calculating the expected ship date of a product. The following library encapsulates the implementation of my library in a self-executing anonymous function: (function (global) { // Public method which calculates tax function calculateTax(price) { return calculateFederalTax(price) + calculateStateTax(price); } // Private method for calculating state tax function calculateStateTax(price) { return price * 0.08; } // Private method for calculating federal tax function calculateFederalTax(price) { return price * 0.02; } // Public method which returns the expected ship date function calculateShipDate(currentDate) { currentDate.setDate(currentDate.getDate() + 4); return currentDate; } // Export public methods WinJS.Namespace.define("CompanyA.Utilities", { calculateTax: calculateTax, calculateShipDate: calculateShipDate } ); })(this); // Show expected ship date var shipDate = CompanyA.Utilities.calculateShipDate(new Date()); console.log(shipDate); // Show price + tax var price = 12.33; var tax = CompanyA.Utilities.calculateTax(price); console.log(price + tax); In the code above, the self-executing anonymous function contains four functions: calculateTax(), calculateStateTax(), calculateFederalTax(), and calculateShipDate(). The following statement is used to expose only the calcuateTax() and the calculateShipDate() functions: // Export public methods WinJS.Namespace.define("CompanyA.Utilities", { calculateTax: calculateTax, calculateShipDate: calculateShipDate } ); Because the calculateTax() and calcuateShipDate() functions are added to the CompanyA.Utilities namespace, you can call these two methods outside of the self-executing function. These are the public methods of your library which form the public API. The calculateStateTax() and calculateFederalTax() methods, on the other hand, are forever hidden within the black hole of the self-executing function. These methods are encapsulated and can never be called outside of scope of the self-executing function. These are the internal methods of your library. Summary The goal of this blog entry was to describe why and how you use namespaces with the WinJS library. You learned how to define namespaces using both the WinJS.Namespace.define() and WinJS.Namespace.defineWithParent() methods. We also discussed how to hide private members and expose public members using the module pattern.

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  • SQL SERVER – Function: Is Function – SQL in Sixty Seconds #004 – Video

    - by pinaldave
    Today is February 29th. An unique date which we only get to observe once every four year. Year 2012 is leap year and SQL Server 2012 is also releasing this year. Yesterday I wrote an article where we have seen observed how using four different function we can create another function which can accurately validate if any year is leap year or not. We will use three functions newly introduced in SQL Server 2012 and demonstrate how we can find if any year is leap year or not. This function uses three of the SQL Server 2012 functions - IIF, EOMONTH and CONCAT. When I wrote this function, this is the sortest function I ever wrote to find out leap year. Please watch the video and let me know if any shorter function can be written to find leap year. More on Leap Yer: Detecting Leap Year in T-SQL using SQL Server 2012 – IIF, EOMONTH and CONCAT Function Date and Time Functions – EOMONTH() – A Quick Introduction Script/Function to Find Last Day of Month  I encourage you to submit your ideas for SQL in Sixty Seconds. We will try to accommodate as many as we can. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL in Sixty Seconds, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Video

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  • ODI 11g – Expert Accelerator for Model Creation

    - by David Allan
    Following on from my post earlier this morning on scripting model and topology creation tonight I thought I’d add a little UI to make those groovy functions a little more palatable. In OWB we have experts for capturing user input, with the groovy console we open up opportunities to build UI around the scripts in a very easy way – even I can do it;-) After a little googling around I found some useful posts on SwingBuilder, the most useful one that I used for the dialog below was this one here. This dialog captures user input for the technology and context for the model and logical schema etc to be created. You can see there are a variety of interesting controls, and its really easy to do. The dialog captures the users input, then when OK is pressed I call the functions from the earlier post to create the logical schema (plus all the other objects) and model. The image below shows what was created, you can see the model (with typo in name), the model is Oracle technology and references the logical schema ORACLE_SCOTT (that I named in dialog above), the logical schema is mapped via the GLOBAL context to the data server ORACLE_SCOTT_DEV (that I named in dialog above), and the physical schema used was just the user name that I connected with – so if you wanted a different user the schema name could be added to the dialog. In a nutshell, one dialog that encapsulates a simpler mechanism for creating a model. You can create your own scripts that use dialogs like this, capture input and process. You can find the groovy script for this is here odi_create_model.groovy, again I wrapped the user capture code in a groovy function and return the result in a variable and then simply call the createLogicalSchema and createModel functions from the previous posting. The script I supplied above has everything you will need. To execute use Tools->Groovy->Open Script and then execute the green play button on the toolbar. Have fun.

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  • Extreme Optimization – Curves (Function Mapping) Part 1

    - by JoshReuben
    Overview ·        a curve is a functional map relationship between two factors (i.e. a function - However, the word function is a reserved word). ·        You can use the EO API to create common types of functions, find zeroes and calculate derivatives - currently supports constants, lines, quadratic curves, polynomials and Chebyshev approximations. ·        A function basis is a set of functions that can be combined to form a particular class of functions.   The Curve class ·        the abstract base class from which all other curve classes are derived – it provides the following methods: ·        ValueAt(Double) - evaluates the curve at a specific point. ·        SlopeAt(Double) - evaluates the derivative ·        Integral(Double, Double) - evaluates the definite integral over a specified interval. ·        TangentAt(Double) - returns a Line curve that is the tangent to the curve at a specific point. ·        FindRoots() - attempts to find all the roots or zeroes of the curve. ·        A particular type of curve is defined by a Parameters property, of type ParameterCollection   The GeneralCurve class ·        defines a curve whose value and, optionally, derivative and integrals, are calculated using arbitrary methods. A general curve has no parameters. ·        Constructor params:  RealFunction delegates – 1 for the function, and optionally another 2 for the derivative and integral ·        If no derivative  or integral function is supplied, they are calculated via the NumericalDifferentiation  and AdaptiveIntegrator classes in the Extreme.Mathematics.Calculus namespace. // the function is 1/(1+x^2) private double f(double x) {     return 1 / (1 + x*x); }   // Its derivative is -2x/(1+x^2)^2 private double df(double x) {     double y = 1 + x*x;     return -2*x* / (y*y); }   // The integral of f is Arctan(x), which is available from the Math class. var c1 = new GeneralCurve (new RealFunction(f), new RealFunction(df), new RealFunction(System.Math.Atan)); // Find the tangent to this curve at x=1 (the Line class is derived from Curve) Line l1 = c1.TangentAt(1);

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  • Organizations &amp; Architecture UNISA Studies &ndash; Chap 7

    - by MarkPearl
    Learning Outcomes Name different device categories Discuss the functions and structure of I/.O modules Describe the principles of Programmed I/O Describe the principles of Interrupt-driven I/O Describe the principles of DMA Discuss the evolution characteristic of I/O channels Describe different types of I/O interface Explain the principles of point-to-point and multipoint configurations Discuss the way in which a FireWire serial bus functions Discuss the principles of InfiniBand architecture External Devices An external device attaches to the computer by a link to an I/O module. The link is used to exchange control, status, and data between the I/O module and the external device. External devices can be classified into 3 categories… Human readable – e.g. video display Machine readable – e.g. magnetic disk Communications – e.g. wifi card I/O Modules An I/O module has two major functions… Interface to the processor and memory via the system bus or central switch Interface to one or more peripheral devices by tailored data links Module Functions The major functions or requirements for an I/O module fall into the following categories… Control and timing Processor communication Device communication Data buffering Error detection I/O function includes a control and timing requirement, to coordinate the flow of traffic between internal resources and external devices. Processor communication involves the following… Command decoding Data Status reporting Address recognition The I/O device must be able to perform device communication. This communication involves commands, status information, and data. An essential task of an I/O module is data buffering due to the relative slow speeds of most external devices. An I/O module is often responsible for error detection and for subsequently reporting errors to the processor. I/O Module Structure An I/O module functions to allow the processor to view a wide range of devices in a simple minded way. The I/O module may hide the details of timing, formats, and the electro mechanics of an external device so that the processor can function in terms of simple reads and write commands. An I/O channel/processor is an I/O module that takes on most of the detailed processing burden, presenting a high-level interface to the processor. There are 3 techniques are possible for I/O operations Programmed I/O Interrupt[t I/O DMA Access Programmed I/O When a processor is executing a program and encounters an instruction relating to I/O it executes that instruction by issuing a command to the appropriate I/O module. With programmed I/O, the I/O module will perform the requested action and then set the appropriate bits in the I/O status register. The I/O module takes no further actions to alert the processor. I/O Commands To execute an I/O related instruction, the processor issues an address, specifying the particular I/O module and external device, and an I/O command. There are four types of I/O commands that an I/O module may receive when it is addressed by a processor… Control – used to activate a peripheral and tell it what to do Test – Used to test various status conditions associated with an I/O module and its peripherals Read – Causes the I/O module to obtain an item of data from the peripheral and place it in an internal buffer Write – Causes the I/O module to take an item of data form the data bus and subsequently transmit that data item to the peripheral The main disadvantage of this technique is it is a time consuming process that keeps the processor busy needlessly I/O Instructions With programmed I/O there is a close correspondence between the I/O related instructions that the processor fetches from memory and the I/O commands that the processor issues to an I/O module to execute the instructions. Typically there will be many I/O devices connected through I/O modules to the system – each device is given a unique identifier or address – when the processor issues an I/O command, the command contains the address of the address of the desired device, thus each I/O module must interpret the address lines to determine if the command is for itself. When the processor, main memory and I/O share a common bus, two modes of addressing are possible… Memory mapped I/O Isolated I/O (for a detailed explanation read page 245 of book) The advantage of memory mapped I/O over isolated I/O is that it has a large repertoire of instructions that can be used, allowing more efficient programming. The disadvantage of memory mapped I/O over isolated I/O is that valuable memory address space is sued up. Interrupts driven I/O Interrupt driven I/O works as follows… The processor issues an I/O command to a module and then goes on to do some other useful work The I/O module will then interrupts the processor to request service when is is ready to exchange data with the processor The processor then executes the data transfer and then resumes its former processing Interrupt Processing The occurrence of an interrupt triggers a number of events, both in the processor hardware and in software. When an I/O device completes an I/O operations the following sequence of hardware events occurs… The device issues an interrupt signal to the processor The processor finishes execution of the current instruction before responding to the interrupt The processor tests for an interrupt – determines that there is one – and sends an acknowledgement signal to the device that issues the interrupt. The acknowledgement allows the device to remove its interrupt signal The processor now needs to prepare to transfer control to the interrupt routine. To begin, it needs to save information needed to resume the current program at the point of interrupt. The minimum information required is the status of the processor and the location of the next instruction to be executed. The processor now loads the program counter with the entry location of the interrupt-handling program that will respond to this interrupt. It also saves the values of the process registers because the Interrupt operation may modify these The interrupt handler processes the interrupt – this includes examination of status information relating to the I/O operation or other event that caused an interrupt When interrupt processing is complete, the saved register values are retrieved from the stack and restored to the registers Finally, the PSW and program counter values from the stack are restored. Design Issues Two design issues arise in implementing interrupt I/O Because there will be multiple I/O modules, how does the processor determine which device issued the interrupt? If multiple interrupts have occurred, how does the processor decide which one to process? Addressing device recognition, 4 general categories of techniques are in common use… Multiple interrupt lines Software poll Daisy chain Bus arbitration For a detailed explanation of these approaches read page 250 of the textbook. Interrupt driven I/O while more efficient than simple programmed I/O still requires the active intervention of the processor to transfer data between memory and an I/O module, and any data transfer must traverse a path through the processor. Thus is suffers from two inherent drawbacks… The I/O transfer rate is limited by the speed with which the processor can test and service a device The processor is tied up in managing an I/O transfer; a number of instructions must be executed for each I/O transfer Direct Memory Access When large volumes of data are to be moved, an efficient technique is direct memory access (DMA) DMA Function DMA involves an additional module on the system bus. The DMA module is capable of mimicking the processor and taking over control of the system from the processor. It needs to do this to transfer data to and from memory over the system bus. DMA must the bus only when the processor does not need it, or it must force the processor to suspend operation temporarily (most common – referred to as cycle stealing). When the processor wishes to read or write a block of data, it issues a command to the DMA module by sending to the DMA module the following information… Whether a read or write is requested using the read or write control line between the processor and the DMA module The address of the I/O device involved, communicated on the data lines The starting location in memory to read from or write to, communicated on the data lines and stored by the DMA module in its address register The number of words to be read or written, communicated via the data lines and stored in the data count register The processor then continues with other work, it delegates the I/O operation to the DMA module which transfers the entire block of data, one word at a time, directly to or from memory without going through the processor. When the transfer is complete, the DMA module sends an interrupt signal to the processor, this the processor is involved only at the beginning and end of the transfer. I/O Channels and Processors Characteristics of I/O Channels As one proceeds along the evolutionary path, more and more of the I/O function is performed without CPU involvement. The I/O channel represents an extension of the DMA concept. An I/O channel ahs the ability to execute I/O instructions, which gives it complete control over I/O operations. In a computer system with such devices, the CPU does not execute I/O instructions – such instructions are stored in main memory to be executed by a special purpose processor in the I/O channel itself. Two types of I/O channels are common A selector channel controls multiple high-speed devices. A multiplexor channel can handle I/O with multiple characters as fast as possible to multiple devices. The external interface: FireWire and InfiniBand Types of Interfaces One major characteristic of the interface is whether it is serial or parallel parallel interface – there are multiple lines connecting the I/O module and the peripheral, and multiple bits are transferred simultaneously serial interface – there is only one line used to transmit data, and bits must be transmitted one at a time With new generation serial interfaces, parallel interfaces are becoming less common. In either case, the I/O module must engage in a dialogue with the peripheral. In general terms the dialog may look as follows… The I/O module sends a control signal requesting permission to send data The peripheral acknowledges the request The I/O module transfers data The peripheral acknowledges receipt of data For a detailed explanation of FireWire and InfiniBand technology read page 264 – 270 of the textbook

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  • Do you want to know more about Oracle Learning Management 12.1?

    - by anders.northeved
    Many of you have upgraded to OLM 12.1 or are in the process of doing so. We have been asked if it was possible to arrange a couple of webcast describing the new functions and features in OLM 12.1 – and of course it is. We will do two webcasts: One on the new features and functions in OLM 12.1.1 and another one on the new features and functions in OLM 12.1.2 + 12.1.3. Each webcast will last for approx. 45 min and afterwards there will be a Q&A session for as long as you have questions! Everybody interested in participating is very welcome to join. Just send an e-mail with the following information to [email protected]: List of participants from your organization Your organization’s current status: Which OLM version you are on and if you have current upgrade plans then we’ll send you a mail with information on how to join. Webcast on OLM 12.1.1 new features: Monday 28th March 5pm CET (8.30pm IST; 4pm UK; 11am EST; 8am PST) Webcast on OLM 12.1.2+OLM 12.1.3 new features: Tuesday 29th March 5pm CET (8.30pm IST; 4pm UK; 11am EST; 8am PST) We are looking forward to your participation!

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  • Rendering Text with the HTML5 Canvas

    - by dwahlin
    In a previous post I walked through the fundamentals of rendering shapes such as squares and circles using the HTML5 Canvas API. In this post I’ll provide a simple example of rendering and rotating text. To render text you can use the fillText() or strokeText() functions which take the text to render as well as the x and y coordinates of where to render it. To rotate text you can use the transform functions available with the HTML5 Canvas such as save(), rotate(), and restore(). To run the live demos that follow click the Result tab in the blue bar of each demo.   Rendering Text This example provides a simple look at how text can be rendered using the HTML5 Canvas. It iterates through a loop, updates the text and font size dynamically, measures the width of the text using the measureText() function, and then calls fillText() to render the text with the desired font size to the screen.   Here’s what the code above renders:   Rotating Text This example shows how text can be rendered and even rotated by using transform functions built into the HTML5 Canvas. The code starts by rendering text the standard way using fillText(). It then saves the state of the canvas performs an x,y coordinate transform (moves to 100, 300 respectively) and then rotates the canvas –90 degrees using the rotate() function. After the text is rendered, the canvas is reverted back to it’s existing state (saved by calling the save() function) by calling the restore() function. An additional line of text is then rendered.   Here’s what the code above renders:   If you’re interested in learning more about the HTML5 Canvas and how it can be used in your Web or Windows 8 applications, check out my HTML5 Canvas Fundamentals course from Pluralsight.

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  • Is there a process-oriented IDE ?

    - by Raveline
    My problem is simple : when I'm programming in an OO paradigm, I'm often having part of a main business process divided in many classes. Which means, if I want to examine the whole functional chain that leads to the output, for debugging or for optimization research, it can be a bit painful. So I was wondering : is there an IDE that let you put a "process tag" on functions coming from different objects, and give you a view of all those functions having the same tag ? edit : To give an example (that I'm making up completely, sorry if it doesn't sound very realistic). Let's say we have the following business process for a HR application : receive a holiday-request by an employee, check the validity of the request, then give an alert to his boss ("one of those lazy programmer wants another day off"); at the same time, let's say the boss will want to have a table of all employee's timetable during the time the employee wants his vacations; then handle the answer of the boss, send a nice little mail to the employee ("No way, lazy bones"). Even if we get rid of everything not purely business-related (mail sending process, db handling to get the useful info, GUI functionalities, and so on), we still have something that doesn't really fit in "one class". I'd like to have an IDE that would give me the opportunity to embrace quickly, at the very least : The function handling the validation of the request by the employee; The function preparing the "timetable" for the boss; The function handling the validation of the request by the boss; I wouldn't put all those functions in the same class (but perhaps that's my mistake ?). This is where my dreamed IDE could be helpful.

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  • When does the "Do One Thing" paradigm become harmful?

    - by Petr
    For the sake of argument here's a sample function that prints contents of a given file line-by-line. Version 1: void printFile(const string & filePath) { fstream file(filePath, ios::in); string line; while (file.good()) { getline(file, line); cout << line << endl; } } I know it is recommended that functions do one thing at one level of abstraction. To me, though code above does pretty much one thing and is fairly atomic. Some books (such as Robert C. Martin's Clean Code) seem to suggest breaking the above code into separate functions. Version 2: void printLine(const string & line) { cout << line << endl; } void printLines(fstream & file) { string line; while (file.good()) { getline(file, line); printLine(line); } } void printFile(const string & filePath) { fstream file(filePath, ios::in); printLines(file); } I understand what they want to achieve (open file / read lines / print line), but isn't it a bit of overkill? The original version is simple and in some sense already does one thing - prints a file. The second version will lead to a large number of really small functions which may be far less legible than the first version. Wouldn't it be, in this case, better to have the code at one place? At which point does the "Do One Thing" paradigm become harmful?

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  • Benchmarking ORM associations

    - by barerd
    I am trying to benchmark two cases of self referential many to many as described in datamapper associations. Both cases consist of an Item clss, which may require many other items. In both cases, I required the ruby benchmark library and source file, created two items and benchmarked require/unrequie functions as below: Benchmark.bmbm do |x| x.report("require:") { item_1.require_item item_2, 10 } x.report("unrequire:") { item_1.unrequire_item item_2 } end To be clear, both functions are datamapper add/modify functions like: componentMaps.create :component_id => item.id, :quantity => quantity componentMaps.all(:component_id => item.id).destroy! and links_to_components.create :component_id => item.id, :quantity => quantity links_to_components.all(:component_id => item.id).destroy! The results are variable and in the range of 0.018001 to 0.022001 for require function in both cases, and 0.006 to 0.01 for unrequire function in both cases. This made me suspicious about the correctness of my test method. Edit I went ahead and compared a "get by primary key case" to a "finding first matching record case" by: (1..10000).each do |i| Item.create :name => "item_#{i}" end Benchmark.bmbm do |x| x.report("Get") { item = Item.get 9712 } x.report("First") { item = Item.first :name => "item_9712" } end where the results were very different like 0 sec compared to 0.0312, as expected. This suggests that the benchmarking works. I wonder whether I benchmarked the two types of associations correctly, and whether a difference between 0.018 and 0.022 sec significant?

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  • Old programmer disappeared. About to hire another programmer. How do I approach this?

    - by pocto
    After spending over one year working on a social network project for me using WordPress and BuddyPress, my programmer has disappeared, even though he got paid every single week, for the whole period. Yes, he's not dead as I used an email tracker to confirm and see he opens my emails, but he doesn't respond. It seems he got another job. I wonder why he just couldn't say so. And I even paid him an advance salary for work he hasn't done. The problem is that I never asked for full documentation for most of the functions he coded in. And there were MANY functions for this 1+ year period, and some of them have bugs that he still didn't fix. Now it seems all confusing. What's the first thing I should do now? How do I proceed? I guess the first thing to do will be to get another programmer, but I want to start on the right foot by having all the current code documented so that any programmer can work on all the functions without issues. Is that the first thing I should do? If yes, how do I go about it? What's the standard type of documentation required for something like this? Can I get a programmer that will just do the documentation for all the codes and fix the bugs or is documentation not really important? Also, do you think getting another "individual" programmer is better or get a company that has programmers working for them, so that if the programmer assigned to my project disappears, another can replace him, without my involvement? I feel this is the approach I should have taken in the beginning.

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  • If a library doesn't provide all my needs, how should I proceed?

    - by 9a3eedi
    I'm developing an application involving math and physics models, and I'd like to use a Math library for things like Matrices. I'm using C#, and so I was looking for some libraries and found Math.NET. I'm under the impression, from past experience, that for math, using a robust and industry-approved third party library is much better than writing your own code. It seems good for many purposes, but it does not provide support for Quaternions, which I need to use as a type. Also, I need some functions in Vector and Matrix that also aren't provided, such as rotation matrices and vector rotation functions, and calculating cross products. At the same time, it provides a lot of functions/classes that I simply do not need, which might mean a lot of unnecessary bloat and complexity. At this rate, should I even bother using the library? Should I write my own math library? Or is it a better idea to stick to the third party library and somehow wrap around it? Perhaps I should make a subclass of the Matrix and Vector type of the library? But isn't that considered bad style? I've also tried looking for other libraries but unfortunately I couldn't find anything suitable.

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  • Information about how much time in spent in a function, based on the input of this function

    - by olchauvin
    Is there a (quantitative) tool to measure performance of functions based on its input? So far, the tools I used to measure performance of my code, tells me how much time I spent in functions (like Jetbrain Dottrace for .Net), but I'd like to have more information about the parameters passed to the function in order to know which parameters impact the most the performance. Let's say that I have function like that: int myFunction(int myParam1, int myParam 2) { // Do and return something based on the value of myParam1 and myParam2. // The code is likely to use if, for, while, switch, etc.... } If would like a tool that would allow me to tell me how much time is spent in myFunction based on the value of myParam1 and myParam2. For example, the tool would give me a result looking like this: For "myFunction" : value | value | Number of | Average myParam1 | myParam2 | call | time ---------|----------|-----------|-------- 1 | 5 | 500 | 301 ms 2 | 5 | 250 | 1253 ms 3 | 7 | 1268 | 538 ms ... That would mean that myFunction has been call 500 times with myParam1=1 and myParam2=5, and that with those parameters, it took on average 301ms to return a value. The idea behind that is to do some statistical optimization by organizing my code such that, the blocs of codes that are the most likely to be executed are tested before the one that are less likely to be executed. To put it bluntly, if I know which values are used the most, I can reorganize the if/while/for etc.. structure of the function (and the whole program) to optimize it. I'd like to find such tools for C++, Java or.Net. Note: I am not looking for technical tips to optimize the code (like passing parameters as const, inlining functions, initializing the capacity of vectors and the like).

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  • What is the best way to handle dynamic content?

    - by user1561753
    So we run a site where there are elements of the interface that could potentially be changed at any moment in the backend. Specifically we run a web service where certain functions are loaded dynamically. However, there are times where we remove certian functions and we want the experience to be as seamless for the user as possible. Now we've considered a few methods of solving this Ping the server every few seconds. If the functions are outdated/no longer available refresh the users page. While this would work the best, I feel like having that much IO can't be too good When the user clicks a function, if it's outdated/no longer available, alert them in the response and refresh the page. This would also work fairly well. I guess I'm more wondering how web apps like Google Docs work where you have content that has to be synced up across multiple users and that isn't more than a few seconds outdated Sorry if this isn't the best place to ask this. I figured this was more of a site architecture question and that this might be the place to ask it over SO.

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  • Handling Types for Real and Complex Matrices in a BLAS Wrapper

    - by mga
    I come from a C background and I'm now learning OOP with C++. As an exercise (so please don't just say "this already exists"), I want to implement a wrapper for BLAS that will let the user write matrix algebra in an intuitive way (e.g. similar to MATLAB) e.g.: A = B*C*D.Inverse() + E.Transpose(); My problem is how to go about dealing with real (R) and complex (C) matrices, because of C++'s "curse" of letting you do the same thing in N different ways. I do have a clear idea of what it should look like to the user: s/he should be able to define the two separately, but operations would return a type depending on the types of the operands (R*R = R, C*C = C, R*C = C*R = C). Additionally R can be cast into C and vice versa (just by setting the imaginary parts to 0). I have considered the following options: As a real number is a special case of a complex number, inherit CMatrix from RMatrix. I quickly dismissed this as the two would have to return different types for the same getter function. Inherit RMatrix and CMatrix from Matrix. However, I can't really think of any common code that would go into Matrix (because of the different return types). Templates. Declare Matrix<T> and declare the getter function as T Get(int i, int j), and operator functions as Matrix *(Matrix RHS). Then specialize Matrix<double> and Matrix<complex>, and overload the functions. Then I couldn't really see what I would gain with templates, so why not just define RMatrix and CMatrix separately from each other, and then overload functions as necessary? Although this last option makes sense to me, there's an annoying voice inside my head saying this is not elegant, because the two are clearly related. Perhaps I'm missing an appropriate design pattern? So I guess what I'm looking for is either absolution for doing this, or advice on how to do better.

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  • Can't find new.h - getting gcc-4.2 on Quantal?

    - by Suyo
    I've been trying to compile the Valve Source SDK (2007) on my machine, but I keep running into the same error: In file included from ../public/tier1/interface.h:50:0, from ../utils/serverplugin_sample/serverplugin_empty.cpp:13: ../public/tier0/platform.h:46:17: new.h: No such file or directory I'm pretty new to C++ coding and compiling, but using apt-file search I tried to use every single suggestion for the required files in the Makefile (libstdc++.a and libgcc_eh.a), and none worked. I then found a note in the Makefile saying gcc 4.2.2 is recommended - I assume the older code won't work with the newer version, but gcc-4.2 is unavailable in 12.10. So my question/s is/are: If my assumption is right - how do I get gcc 4.2.2 on Quantal? If my assumption is wrong - what else could be the problem here? Relevant portion of the Makefile: # compiler options (gcc 3.4.1 will work - 4.2.2 recommended) CC=/usr/bin/gcc CPLUS=/usr/bin/g++ CLINK=/usr/bin/gcc CPP_LIB="/usr/lib/gcc/x86_64-w64-mingw32/4.6/libstdc++.a /usr/lib/gcc/x86_64-w64-mingw32/4.6/libgcc_eh.a" # GCC 4.2.2 optimization flags, if you're using anything below, don't use these! OPTFLAGS=-O1 -fomit-frame-pointer -ffast-math -fforce-addr -funroll-loops -fthread-jumps -fcrossjumping -foptimize-sibling-calls -fcse-follow-jumps -fcse-skip-blocks -fgcse -fgcse-lm -fexpensive-optimizations -frerun-cse-after-loop -fcaller-saves -fpeephole2 -fschedule-insns2 -fsched-interblock -fsched-spec -fregmove -fstrict-overflow -fdelete-null-pointer-checks -freorder-blocks -freorder-functions -falign-functions -falign-jumps -falign-loops -falign-labels -ftree-vrp -ftree-pre -finline-functions -funswitch-loops -fgcse-after-reload #OPTFLAGS= # put any compiler flags you want passed here USER_CFLAGS=-m32

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  • Motivation for service layer (instead of just copying dlls)?

    - by BornToCode
    I'm creating an application which has 2 different UIs so I'm making it with a service layer which I understood is appropriate for such case. However I found myself just creating web methods for every single method I have in the BL layer, so the services basically built from methods that looks like this: return customers_bl.Get_Customer_Prices(customer_id); I understood that a main point of the service layer is to prevent duplication of code so I asked myself - well, why not just import the BL.dll (and the DAL.dll) to the other UI, and whenever making a change re-copy the dll files, it might not be so 'neat', but is the all purpose of the service layer to prevent this? {I know something is wrong in my approach, I'm probably missing the importance of service layer, I'd like to get more motivation to create another layer, especially because as it is I found that many of my BL functions ALREADY looks like: return customers_dal.Get_Customer_Prices(cust_id) which led me to ask: was it really necessary to create the BL just because on several functions I actually have LOGIC inside the BL?} so I'm looking for more motivation to creating ONE MORE layer, I'm sure it's not just to make it more convenient that I won't have to re-copy the dlls on changes? Am I grasping it wrong? Any simple guidelines on how to design service layer (corresponding to all the BL layer functions or not? any simple example?) any enlightenment on the subject?

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  • Motivation for a service layer (instead of just copying dlls)?

    - by BornToCode
    I'm creating an application which has 2 different UIs so I'm making it with a service layer which I understood is appropriate for such scenario. However I found myself just creating web methods for every single method I have in the BL layer, so the services basically built from methods that looks like this: return customers_bl.Get_Customer_Prices(customer_id); I understood that a main point of the service layer is to prevent duplication of code so I asked myself - why not just import the BL.DLL (and the dal.dll) to the other UI, and whenever making a change re-copy the dlls, it might not be so 'neat', but still less hassle than one more layer? {I know something is wrong in my approach, I'm probably missing the importance of service layer, I'd like to get more motivation to create another layer, especially because as it is I found that many of my BL functions ALREADY looks like: return customers_dal.Get_Customer_Prices(cust_id) which led me to ask: was it really necessary to create the BL just because on several functions I actually have LOGIC inside the BL?} so I'm looking for more motivation to creating ONE MORE layer, I'm sure it's not just to make it more convenient that I won't have to re-copy the dlls on changes? Am I grasping it wrong? Any simple guidelines on how to design service layer (corresponding to all the BL layer functions or not? any simple example?) any enlightenment on the subject?

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  • How to match responses from a server with their corresponding requests? [closed]

    - by Deele
    There is a server that responds to requests on a socket. The client has functions to emit requests and functions to handle responses from the server. The problem is that the request sending function and the response handling function are two unrelated functions. Given a server response X, how can I know whether it's a response to request X or some other request Y? I would like to make a construct that would ensure that response X is definitely the answer to request X and also to make a function requestX() that returns response X and not some other response Y. This question is mostly about the general programming approach and not about any specific language construct. Preferably, though, the answer would involve Ruby, TCP sockets, and PHP. My code so far: require 'socket' class TheConnection def initialize(config) @config = config end def send(s) toConsole("--> #{s}") @conn.send "#{s}\n", 0 end def connect() # Connect to the server begin @conn = TCPSocket.open(@config['server'], @config['port']) rescue Interrupt rescue Exception => detail toConsole('Exception: ' + detail.message()) print detail.backtrace.join('\n') retry end end def getSpecificAnswer(input) send "GET #{input}" end def handle_server_input(s) case s.strip when /^Hello. (.*)$/i toConsole "[ Server says hello ]" send "Hello to you too! #{$1}" else toConsole(s) end end def main_loop() while true ready = select([@conn, $stdin], nil, nil, nil) next if !ready for s in ready[0] if s == $stdin then return if $stdin.eof s = $stdin.gets send s elsif s == @conn then return if @conn.eof s = @conn.gets handle_server_input(s) end end end end def toConsole(msg) t = Time.new puts t.strftime("[%H:%M:%S]") + ' ' + msg end end @config = Hash[ 'server'=>'test.server.com', 'port'=>'2020' ] $conn = TheConnection.new(@config) $conn.connect() $conn.getSpecificAnswer('itemsX') begin $conn.main_loop() rescue Interrupt rescue Exception => detail $conn.toConsole('Exception: ' + detail.message()) print detail.backtrace.join('\n') retry end

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  • Is there a better way to organize my module tests that avoids an explosion of new source files?

    - by luser droog
    I've got a neat (so I thought) way of having each of my modules produce a unit-test executable if compiled with the -DTESTMODULE flag. This flag guards a main() function that can access all static data and functions in the module, without #including a C file. From the README: -- Modules -- The various modules were written and tested separately before being coupled together to achieve the necessary basic functionality. Each module retains its unit-test, its main() function, guarded by #ifdef TESTMODULE. `make test` will compile and execute all the unit tests, producing copious output, but importantly exitting with an appropriate success or failure code, so the `make test` command will fail if any of the tests fail. Module TOC __________ test obj src header structures CONSTANTS ---- --- --- --- -------------------- m m.o m.c m.h mfile mtab TABSZ s s.o s.c s.h stack STACKSEGSZ v v.o v.c v.h saverec_ f.o f.c f.h file ob ob.o ob.c ob.h object ar ar.o ar.c ar.h array st st.o st.c st.h string di di.o di.c di.h dichead dictionary nm nm.o nm.c nm.h name gc gc.o gc.c gc.h garbage collector itp itp.c itp.h context osunix.o osunix.c osunix.h unix-dependent functions It's compile by a tricky bit of makefile, m:m.c ob.h ob.o err.o $(CORE) itp.o $(OP) cc $(CFLAGS) -DTESTMODULE $(LDLIBS) -o $@ $< err.o ob.o s.o ar.o st.o v.o di.o gc.o nm.o itp.o $(OP) f.o where the module is compiled with its own C file plus every other object file except itself. But it's creating difficulties for the kindly programmer who offered to write the Autotools files for me. So the obvious way to make it "less weird" would be to bust-out all the main functions into separate source files. But, but ... Do I gotta?

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