Search Results

Search found 4842 results on 194 pages for 'computation expression'.

Page 78/194 | < Previous Page | 74 75 76 77 78 79 80 81 82 83 84 85  | Next Page >

  • How or why would this mechanic (not) work to bring game balance to a singleplayer RPG? [closed]

    - by 0xFFF1
    Mechanic details The player, the monsters, and the merchants act as three separate parties. The player needs to beat up monsters for exp points and resources to sell and to buy potions from merchants to continue to fight. The monsters need healing and reviving to survive (also bought from merchants) and the merchants need potion ingredients from the player and the monsters to make potions to sell. These potions are only able to be processed in such bulk by merchants thus their potions would be cheaper than making them yourself. Only the monsters can farm ingredients in bulk. Only the player is or has to be overly aggressive (in bulk). Monsters can farm and produce "Level up candies" that do the work of exp. they are eaten right away after they are made and are never stockpiled or held for fear of the player and merchants who want to sell to the player. The monsters will defend themselves. Reviving is very expensive. The merchants can be found either with a concerned expression or a grinning expression based on how much profit they are making compared to their morale standing. The economies of each monster town and merchant city are distinct but interconnected. Magic Swords are worth a lot. So what I need to know is what concerns would there be to design a game around this mechanic and/or design this mechanic around a developing game. which would fare better? Is game balance an issue here? (how strong the monsters get or how quickly they die off based on the player's input into the system), Or is game balance solely in the hands of the player? (he decides if he overkills monsters or get underleveled.) What do I need to think about to make sure it isn't too easy or too hard to swing the amount/strength of monsters compared to the player and the amount of profit the merchants get vs the player. Would indicating how out of whack things are getting in game help with this?

    Read the article

  • Microsoft and innovation: IIF() method

    This Saturday I was watching a couple of eLearning videos from TrainSignal (thanks to the subscription I have with Pluralsight) on Querying Microsoft SQL Server 2012 (exam 70-461). 'Innovation' by Microsoft I kept myself busy learning 'new' things about Microsoft SQL Server 2012 and some best practices. It was incredible 'innovative' to see that there is an additional logic function called IIF() available now: Returns one of two values depending on the value of a logical expression. IIF(lExpression, eExpression1, eExpression2) Ups, my bad... That's actually taken from the syntax page of Visual FoxPro 9.0 SP 2. And tada, at least seven (7+) years later, there's the recent IIF() Transact-SQL version of that function: Returns one of two values, depending on whether the Boolean expression evaluates to true or false in SQL Server 2012. IIF ( boolean_expression, true_value, false_value ) Now, that's what I call innovation! But we all know what happened to Visual FoxPro... It has been reincarnated in form of Visual Studio LightSwitch (and SQL Server). Enough ranting... Happy coding!

    Read the article

  • CS Concentrations and Career Paths

    - by xbonez
    I'm approaching the end of Sophomore year in college (Studying Computer Science), and very soon I'm going to have to decide on my concentration, but I honestly don't know what each concentration means. I basically have two questions: 1. How much influence does your concentration have on your career path? For example, would a video game development company only look at people with a concentration in Game Development? 2.It would be great if you guys could, in a line or two, tell me what sort of jobs am I looking at for each of the concentrations? I need to pick at least two of the 9 below. - Algorithms and Data Structures - Artificial Intelligence - Computer and Network Society - Computer graphics and vision - Human-Computer Interaction - Game Development and Design - Numeric and Symbolic Computation - Programming languages - Systems

    Read the article

  • Distinct Count of Customers in a SCD Type 2 in #DAX

    - by Marco Russo (SQLBI)
    If you have a Slowly Changing Dimension (SCD) Type 2 for your customer and you want to calculate the number of distinct customers that bought a product, you cannot use the simple formula: Customers := DISTINCTCOUNT( FactTable[Customer Id] ) ) because it would return the number of distinct versions of customers. What you really want to do is to calculate the number of distinct application keys of the customers, that could be a lower number than the number you’ve got with the previous formula. Assuming that a Customer Code column in the Customers dimension contains the application key, you should use the following DAX formula: Customers := COUNTROWS( SUMMARIZE( FactTable, Customers[Customer Code] ) ) Be careful: only the version above is really fast, because it is solved by xVelocity (formerly known as VertiPaq) engine. Other formulas involving nested calculations might be more complex and move computation to the formula engine, resulting in slower query. This is absolutely an interesting pattern and I have to say it’s a killer feature. Try to do the same in Multidimensional…

    Read the article

  • Code &amp; Slides &ndash; SDE &ndash; What&rsquo;s new in Silverlight 4

    - by Timmy Kokke
    Last Tuesday the Software Developers Network – SDN organized another SDE. I’ve had the opportunity to present a session about Silverlight 4. I talked about lots of new features in Silverlight 4 and Expression Blend 4, focused on the Out-Of-Browser features.     The slides of my presentation can be downloaded here.   In my presentation I demonstrated a couple of features from my new pet project “SilverAmp”. This project is based on the legendary WinAmp, but made entirely in Silverlight. I use it to try out many new Silverlight 4 features. It’s not finished yet, but useful already. It runs outside the browser with elevated trust. It reads your local MyMusic folder and uses the TagLib library to read the ID3 tags of the mp3s it finds. SilverAmp is using MEF for extensibility. It uses a custom Window Chrome, designed in Expression Design. And it shows a notification window when a new song starts to play.   In the future it is going to get song information from Last.FM, will be able to show YouTube videos inside itself and it will tweet about what you are playing. The project will be fully documented to function as a reference implementation for the new Silverlight 4 features.   You can download the source on  http://SilverAmp.codeplex.com   Below are two screenshot of SilverAmp.                     If you have any questions, comments,  issues or feature requests let me know.

    Read the article

  • Most efficient AABB - Ray intersection algorithm for input/output distance calculation

    - by Tobbey
    Thanks to the following thread : most efficient AABB vs Ray collision algorithms I have seen very fast algorithm for ray/AABB intersection point computation. Unfortunately, most of the recent algorithm are accelerated by omitting the "output" intersection point of the box. In my application, I would interested in getting both the the distance from source ray to input: t0 and source ray to output of bounding box: t1. I have seen for instance Eisemann designed a very fast version regarding plucker, smits, ... , but it does not compare the case when both input/output distance should be computed see: http://www.cg.cs.tu-bs.de/publications/Eisemann07FRA/ Does someone know where I can find more information on algorithm performances for the specific input/output problem ? Thank you in advance

    Read the article

  • Using position function for accessing particular node when using While Activity in SOA 11.1.1.5

    - by AJ
    Hi If you are using while activity in SOA Suite 11.1.1.5 and within loop you have a requirement to access repeating node of XML. You might need to use below XPATH expression for accessing the node. Here is the XML that I am using for this example <?xml version='1.0' encoding='UTF-8'?> David DemoJob 1 2012-04-15 40000 0 10 Steve TestJob 1 2012-04-15 40000 0 10 Here you can notice that Emp node is repeating i.e. EmpCollection node will contain multiple employees. Now in loop one of assign activity you need to access a particular node for e.g. For first time loop runs you want to access first node and second time second node and so on. You need to make use of postion() function like bpws:getVariableData('Receive1_Read_InputVariable','body','/ns4:EmpCollection/ns4:Emp[position()=$loopCounter]/ns4:job') Please Note: Here loopCounter is a variable that we have created of type xsd:int and prior to loop we have initialized a value of 1. Loop will run depending on the number of Emp nodes present at runtime. For that in while Activity you can use below XPATH expression ora:countNodes('Receive1_Read_InputVariable','body','/ns4:EmpCollection/ns4:Emp')=bpws:getVariableData('loopCounter') Do let me know in case of any issues or concern. Cheers AJ

    Read the article

  • Getting to math applications gradually

    - by den-javamaniac
    I'm currently getting a formal degree related to computation, in particular my current focus is numerical programming, scientific computing and machine learning. I'd love to apply that knowledge in game dev and expand it with statistics, probability theory, and graph theory (probably even linear algebra). The question is: which spheres of gamedev are filled with such math stuff, is it possible to advance in those without being a part of a group of people and how to get to it gradually? P.S.: I've got experience with commercial java dev and am getting my hands on C/C++ at the moment, however, I'm opened to go ahead and try Unity3D and etc.

    Read the article

  • Frame timing for GLFW versus GLUT

    - by linello
    I need a library which ensures me that the timing between frames are more constant as possible during an experiment of visual psychophics. This is usually done synchronizing the refresh rate of the screen with the main loop. For example if my monitor runs at 60Hz I would like to specify that frequency to my framework. For example if my gameloop is the following void gameloop() { // do some computation printDeltaT(); Flip buffers } I would like to have printed a constant time interval. Is it possible with GLFW?

    Read the article

  • migrating from struts2, looking for a new framework

    - by adhg
    We are supposed to start a relatively big project that will require lots of computation and analysis. Presentation (UI) for the end user is very crucial (graphs, tabels...) So far we've been using struts2. It's ok+. It has some drawbacks (specially if you work with tiles and all that XML) but if you get the lingo - you're ok. One option on the table is to continue using struts2 with jquery and all the other stuff that we've been doing for so long. Alternatively, I think we have an opportunity to learn something new and maybe a bit better then struts2. My question is this: Anyone has migrated from struts2 to something new and can share the experience. Or had some great experience witha particular java framework. Many thanks for any pointers.

    Read the article

  • Oracle Identity Manager ADF Customization

    - by Arda Eralp
    This blog entry includes an example about customization Oracle Identity Manager (OIM) Self Service screen. Before customization all users that can be logged in OIM Self Service can see "Administration" tab on left menu. On this example we create "Managers" role and only users that have managers role can see "Administration" tab. Step 1: Create "Manager" role  Step 2: Create Sandbox  Step 3: Customize ADF Select "Customize" on the top menu Select "Source" instead of "Design" on top  Select "Administration" tab with blue rectangle and edit component Edit "visible" with expression builder #{oimcontext.currentUser.roles['Manager'] != null} Apply Step 4: Apply to All and Publish sandbox Notes:  This table objects can use for expression. Objects Description #{oimcontext.currentUser['ATTRIBUTE_NAME']} #{oimcontext.currentUser['UDF_NAME']} #{oimcontext.currentUser.roles} #{oimcontext.currentUser.roles['SYSTEM ADMINISTRATORS'] != null} Boolean #{oimcontext.currentUser.adminRoles['OrclOIMSystemAdministrator'] != null} Boolean

    Read the article

  • My rhythm game runs choppy even with high frame rate

    - by felipedrl
    I'm coding a rhythm game and the game runs smoothly with uncapped fps. But when I try to cap it around 60 the game updates in little chunks, like hiccups, as if it was skipping frames or at a very low frame rate. The reason I need to cap frame rate is because in some computers I tested, the fps varies a lot (from ~80 - ~250 fps) and those drops are noticeable and degrade response time. Since this is a rhythm game this is very important. This issue is driving me crazy. I've spent a few weeks already on it and still can't figure out the problem. I hope someone more experienced than me could shed some light on it. I'll try to put here all the hints I've tried along with two pseudo codes for game loops I tried, so I apologize if this post gets too lengthy. 1st GameLoop: const uint UPDATE_SKIP = 1000 / 60; uint nextGameTick = SDL_GetTicks(); while(isNotDone) { // only false when a QUIT event is generated! if (processEvents()) { if (SDL_GetTicks() > nextGameTick) { update(UPDATE_SKIP); render(); nextGameTick += UPDATE_SKIP; } } } 2nd Game Loop: const uint UPDATE_SKIP = 1000 / 60; while (isNotDone) { LARGE_INTEGER startTime; QueryPerformanceCounter(&startTime); // process events will return false in case of a QUIT event processed if (processEvents()) { update(frameTime); render(); } LARGE_INTEGER endTime; do { QueryPerformanceCounter(&endTime); frameTime = static_cast<uint>((endTime.QuadPart - startTime.QuadPart) * 1000.0 / frequency.QuadPart); } while (frameTime < UPDATE_SKIP); } [1] At first I thought it was a timer resolution problem. I was using SDL_GetTicks, but even when I switched to QueryPerformanceCounter, supposedly less granular, I saw no difference. [2] Then I thought it could be due to a rounding error in my position computation and since game updates are smaller in high FPS that would be less noticeable. Indeed there is an small error, but from my tests I realized that it is not enough to produce the position jumps I'm getting. Also, another intriguing factor is that if I enable vsync I'll get smooth updates @60fps regardless frame cap code. So why not rely on vsync? Because some computers can force a disable on gfx card config. [3] I started printing the maximum and minimum frame time measured in 1sec span, in the hope that every a few frames one would take a long time but still not enough to drop my fps computation. It turns out that, with frame cap code I always get frame times in the range of [16, 18]ms, and still, the game "does not moves like jagger". [4] My process' priority is set to HIGH (Windows doesn't allow me to set REALTIME for some reason). As far as I know there is only one thread running along with the game (a sound callback, which I really don't have access to it). I'm using AudiereLib. I then disabled Audiere by removing it from the project and still got the issue. Maybe there are some others threads running and one of them is taking too long to come back right in between when I measured frame times, I don't know. Is there a way to know which threads are attached to my process? [5] There are some dynamic data being created during game run. But It is a little bit hard to remove it to test. Maybe I'll have to try harder this one. Well, as I told you I really don't know what to try next. Anything, I mean, anything would be of great help. What bugs me more is why at 60fps & vsync enabled I get an smooth update and at 60fps & no vsync I don't. Is there a way to implement software vsync? I mean, query display sync info? Thanks in advance. I appreciate the ones that got this far and yet again I apologize for the long post. Best Regards from a fellow coder.

    Read the article

  • Can higher-order functions in FP be interpreted as some kind of dependency injection?

    - by Giorgio
    According to this article, in object-oriented programming / design dependency injection involves a dependent consumer, a declaration of a component's dependencies, defined as interface contracts, an injector that creates instances of classes that implement a given dependency interface on request. Let us now consider a higher-order function in a functional programming language, e.g. the Haskell function filter :: (a -> Bool) -> [a] -> [a] from Data.List. This function transforms a list into another list and, in order to perform its job, it uses (consumes) an external predicate function that must be provided by its caller, e.g. the expression filter (\x -> (mod x 2) == 0) [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] selects all even numbers from the input list. But isn't this construction very similar to the pattern illustrated above, where the filter function is the dependent consumer, the signature (a -> Bool) of the function argument is the interface contract, the expression that uses the higher-order is the injector that, in this particular case, injects the implementation (\x -> (mod x 2) == 0) of the contract. More in general, can one relate higher-order functions and their usage pattern in functional programming to the dependency injection pattern in object-oriented languages? Or in the inverse direction, can dependency injection be compared to using some kind of higher-order function?

    Read the article

  • What makes an application memory bandwidth bound?

    - by TheLQ
    This has been something that's been bothering me for a while: What makes an application memory bandwidth bound? For example, take this monstrosity of a computer that calculated the 5 trillionth digit of pi (and later 10 trillionth digit). I was surprised that they choose the lower but faster 98 GB RAM at 1066 MHz instead of the larger but slower 144 GB at 800 MHz. This is especially surprising considering they are using 22 TB HD array to store the results from computation; more RAM means less need for hard drives. Maybe its because I don't write applications for HPC servers, but how would RAM be the bottleneck? Are there any other non-HPC applications that usually run into this problem?

    Read the article

  • Using visitor pattern with large object hierarchy

    - by T. Fabre
    Context I've been using with a hierarchy of objects (an expression tree) a "pseudo" visitor pattern (pseudo, as in it does not use double dispatch) : public interface MyInterface { void Accept(SomeClass operationClass); } public class MyImpl : MyInterface { public void Accept(SomeClass operationClass) { operationClass.DoSomething(); operationClass.DoSomethingElse(); // ... and so on ... } } This design was, however questionnable, pretty comfortable since the number of implementations of MyInterface is significant (~50 or more) and I didn't need to add extra operations. Each implementation is unique (it's a different expression or operator), and some are composites (ie, operator nodes that will contain other operator/leaf nodes). Traversal is currently performed by calling the Accept operation on the root node of the tree, which in turns calls Accept on each of its child nodes, which in turn... and so on... But the time has come where I need to add a new operation, such as pretty printing : public class MyImpl : MyInterface { // Property does not come from MyInterface public string SomeProperty { get; set; } public void Accept(SomeClass operationClass) { operationClass.DoSomething(); operationClass.DoSomethingElse(); // ... and so on ... } public void Accept(SomePrettyPrinter printer) { printer.PrettyPrint(this.SomeProperty); } } I basically see two options : Keep the same design, adding a new method for my operation to each derived class, at the expense of maintainibility (not an option, IMHO) Use the "true" Visitor pattern, at the expense of extensibility (not an option, as I expect to have more implementations coming along the way...), with about 50+ overloads of the Visit method, each one matching a specific implementation ? Question Would you recommand using the Visitor pattern ? Is there any other pattern that could help solve this issue ?

    Read the article

  • How to Edit aspx, Cshtml and other kind of files live on FTP server ?

    - by Anirudha
    Originally posted on: http://geekswithblogs.net/anirugu/archive/2013/06/27/how-to-edit-aspx-cshtml-and-other-kind-of-files.aspxMany time we just want to make a small changes on site and we don’t want to download the whole project again. In this post I will show you some good way to do it.   People who have Expression Web 4 can do it. I tried it and it’s work good with aspx file. If you have site in asp.net and use aspx engine then this is a good option. Well, Expression Web is free (previously paid software). A another good option is Komodo Edit. You can use komodo edit and few plugin to make FTP editing work for you. The problem in these 2 apps are they don’t have syntax highlight and support for CSHTML file which are introduced with MVC 3. For this I suggest you to go with webmatrix. You can use Webmatrix to edit cshtml file online. Remember that Webmatrix don’t support Compiling of MVC project. You need Visual Web developer Express at-least to compile your project. if you are in hurry try  https://c9.io/ put your FTP settings and you just got your hands ready to make changes on live site. If you have anything else in your mind share it here.

    Read the article

  • How do i return integers from a string ?

    - by kannan.ambadi
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:0in; mso-para-margin-bottom:.0001pt; 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-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Suppose you are passing a string(for e.g.: “My name has 1 K, 2 A and 3 N”)  which may contain integers, letters or special characters. I want to retrieve only numbers from the input string. We can implement it in many ways such as splitting the string into an array or by using TryParse method. I would like to share another idea, that’s by using Regular expressions. All you have to do is, create an instance of Regular Expression with a specified pattern for integer. Regular expression class defines a method called Split, which splits the specified input string based on the pattern provided during object initialization.     We can write the code as given below:   public static int[] SplitIdSeqenceValues(object combinedArgs)         {             var _argsSeperator = new Regex(@"\D+", RegexOptions.Compiled);               string[] splitedIntegers = _argsSeperator.Split(combinedArgs.ToString());               var args = new int[splitedIntegers.Length];               for (int i = 0; i < splitedIntegers.Length; i++)                 args[i] = MakeSafe.ToSafeInt32(splitedIntegers[i]);                           return args;         }    It would be better, if we set to RegexOptions.Compiled so that the regular expression will have performance boost by faster compilation.   Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:0in; mso-para-margin-bottom:.0001pt; 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-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Happy Programming  :))   

    Read the article

  • Creating an ASP.NET report using Visual Studio 2010 - Part 2

    - by rajbk
    We continue building our report in this three part series. Creating an ASP.NET report using Visual Studio 2010 - Part 1 Creating an ASP.NET report using Visual Studio 2010 - Part 3 Creating the Client Report Definition file (RDLC) Add a folder called “RDLC”. This will hold our RDLC report.   Right click on the RDLC folder, select “Add new item..” and add an “RDLC” name of “Products”. We will use the “Report Wizard” to walk us through the steps of creating the RDLC.   In the next dialog, give the dataset a name called “ProductDataSet”. Change the data source to “NorthwindReports.DAL” and select “ProductRepository(GetProductsProjected)”. The fields that are returned from the method are shown on the right. Click next.   Drag and drop the ProductName, CategoryName, UnitPrice and Discontinued into the Values container. Note that you can create much more complex grouping using this UI. Click Next.   Most of the selections on this screen are grayed out because we did not choose a grouping in the previous screen. Click next. Choose a style for your report. Click next. The report graphic design surface is now visible. Right click on the report and add a page header and page footer. With the report design surface active, drag and drop a TextBox from the tool box to the page header. Drag one more textbox to the page header. We will use the text boxes to add some header text as shown in the next figure. You can change the font size and other properties of the textboxes using the formatting tool bar (marked in red). You can also resize the columns by moving your cursor in between columns and dragging. Adding Expressions Add two more text boxes to the page footer. We will use these to add the time the report was generated and page numbers. Right click on the first textbox in the page footer and select “Expression”. Add the following expression for the print date (note the = sign at the left of the expression in the dialog below) "© Northwind Traders " & Format(Now(),"MM/dd/yyyy hh:mm tt") Right click on the second text box and add the following for the page count.   Globals.PageNumber & " of " & Globals.TotalPages Formatting the page footer is complete.   We are now going to format the “Unit Price” column so it displays the number in currency format.  Right click on the [UnitPrice] column (not header) and select “Text Box Properties..” Under “Number”, select “Currency”. Hit OK. Adding a chart With the design surface active, go to the toolbox and drag and drop a chart control. You will need to move the product list table down first to make space for the chart contorl. The document can also be resized by dragging on the corner or at the page header/footer separator. In the next dialog, pick the first chart type. This can be changed later if needed. Click OK. The chart gets added to the design surface.   Click on the blue bars in the chart (not legend). This will bring up drop locations for dropping the fields. Drag and drop the UnitPrice and CategoryName into the top (y axis) and bottom (x axis) as shown below. This will give us the total unit prices for a given category. That is the best I could come up with as far as what report to render, sorry :-) Delete the legend area to get more screen estate. Resize the chart to your liking. Change the header, x axis and y axis text by double clicking on those areas. We made it this far. Let’s impress the client by adding a gradient to the bar graph :-) Right click on the blue bar and select “Series properties”. Under “Fill”, add a color and secondary color and select the Gradient style. We are done designing our report. In the next section you will see how to add the report to the report viewer control, bind to the data and make it refresh when the filter criteria are changed.   Creating an ASP.NET report using Visual Studio 2010 - Part 3

    Read the article

  • Formal Languages, Inductive Proofs &amp; Regular Expressions

    - by MarkPearl
    So I am slogging away at my UNISA stuff. I have just finished doing the initial once non stop read through the first 11 chapters of my COS 201 Textbook - “Introduction to Computer Theory 2nd Edition” by Daniel Cohen. It has been an interesting couple of days, with familiar concepts coming up as well as some new territory. In this posting I am going to cover the first couple of chapters of the book. Let start with Formal Languages… What exactly is a formal language? Pretty much a no duh question for me but still a good one to ask – a formal language is a language that is defined in a precise mathematical way. Does that mean that the English language is a formal language? I would say no – and my main motivation for this is that one can have an English sentence that is correct grammatically that is also ambiguous. For example the ambiguous sentence: "I once shot an elephant in my pyjamas.” For this and possibly many other reasons that I am unaware of, English is termed a “Natural Language”. So why the importance of formal languages in computer science? Again a no duh question in my mind… If we want computers to be effective and useful tools then we need them to be able to evaluate a series of commands in some form of language that when interpreted by the device no confusion will exist as to what we were requesting. Imagine the mayhem that would exist if a computer misinterpreted a command to print a document and instead decided to delete it. So what is a Formal Language made up of… For my study purposes a language is made up of a finite alphabet. For a formal language to exist there needs to be a specification on the language that will describe whether a string of characters has membership in the language or not. There are two basic ways to do this: By a “machine” that will recognize strings of the language (e.g. Finite Automata). By a rule that describes how strings of a language can be formed (e.g. Regular Expressions). When we use the phrase “string of characters”, we can also be referring to a “word”. What is an Inductive Proof? So I am not to far into my textbook and of course it starts referring to proofs and different types. I have had to go through several different approaches of proofs in the past, but I can never remember their formal names , so when I saw “inductive proof” I thought to myself – what the heck is that? Google to the rescue… An inductive proof is like a normal proof but it employs a neat trick which allows you to prove a statement about an arbitrary number n by first proving it is true when n is 1 and then assuming it is true for n=k and showing it is true for n=k+1. The idea is that if you want to show that someone can climb to the nth floor of a fire escape, you need only show that you can climb the ladder up to the fire escape (n=1) and then show that you know how to climb the stairs from any level of the fire escape (n=k) to the next level (n=k+1). Does this sound like a form of recursion? No surprise then that in the same chapter they deal with recursive definitions. An example of a recursive definition for the language EVEN would the 3 rules below: 2 is in EVEN If x is in EVEN then so is x+2 The only elements in the set EVEN are those that be produced by the rules above. Nothing to exciting… So if a definition for a language is done recursively, then it makes sense that the language can be proved using induction. Regular Expressions So I am wondering to myself what use is this all – in fact – I find this the biggest challenge to any university material is that it is quite hard to find the immediate practical applications of some theory in real life stuff. How great was my joy when I suddenly saw the word regular expression being introduced. I had been introduced to regular expressions on Stack Overflow where I was trying to recognize if some text measurement put in by a user was in a valid form or not. For instance, the imperial system of measurement where you have feet and inches can be represented in so many different ways. I had eventually turned to regular expressions as an easy way to check if my parser could correctly parse the text or not and convert it to a normalize measurement. So some rules about languages and regular expressions… Any finite language can be represented by at least one if not more regular expressions A regular expressions is almost a rule syntax for expressing how regular languages can be formed regular expressions are cool For a regular expression to be valid for a language it must be able to generate all the words in the language and no other words. This is important. It doesn’t help me if my regular expression parses 100% of my measurement texts but also lets one or two invalid texts to pass as well. Okay, so this posting jumps around a bit – but introduces some very basic fundamentals for the subject which will be built on in later postings… Time to go and do some practical examples now…

    Read the article

  • SQL SERVER – Identifying guest User using Policy Based Management

    - by pinaldave
    If you are following my recent blog posts, you may have noticed that I’ve been writing a lot about Guest User in SQL Server. Here are all the blog posts which I have written on this subject: SQL SERVER – Disable Guest Account – Serious Security Issue SQL SERVER – Force Removing User from Database – Fix: Error: Could not drop login ‘test’ as the user is currently logged in SQL SERVER – Detecting guest User Permissions – guest User Access Status SQL SERVER – guest User and MSDB Database – Enable guest User on MSDB Database One of the requests I received was whether we could create a policy that would prevent users unable guest user in user databases. Well, here is a quick tutorial to answer this. Let us see how quickly we can do it. Requirements Check if the guest user is disabled in all the user-created databases. Exclude master, tempdb and msdb database for guest user validation. We will create the following conditions based on the above two requirements: If the name of the user is ‘guest’ If the user has connect (@hasDBAccess) permission in the database Check in All user databases, except: master, tempDB and msdb Once we create two conditions, we will create a policy which will validate the conditions. Condition 1: Is the User Guest? Expand the Database >> Management >> Policy Management >> Conditions Right click on the Conditions, and click on “New Condition…”. First we will create a condition where we will validate if the user name is ‘guest’, and if it’s so, then we will further validate if it has DB access. Check the image for the necessary configuration for condition: Facet: User Expression: @Name = ‘guest’ Condition 2: Does the User have DBAccess? Expand the Database >> Management >> Policy Management >> Conditions Right click on Conditions and click on “New Condition…”. Now we will validate if the user has DB access. Check the image for necessary configuration for condition: Facet: User Expression: @hasDBAccess = False Condition 3: Exclude Databases Expand the Database >> Management >> Policy Management >> Conditions Write click on Conditions and click on “New Condition…” Now we will create condition where we will validate if database name is master, tempdb or msdb and if database name is any of them, we will not validate our first one condition with them. Check the image for necessary configuration for condition: Facet: Database Expression: @Name != ‘msdb’ AND @Name != ‘tempdb’ AND @Name != ‘master’ The next step will be creating a policy which will enforce these conditions. Creating a Policy Right click on Policies and click “New Policy…” Here, we justify what condition we want to validate against what the target is. Condition: Has User DBAccess Target Database: Every Database except (master, tempdb and MSDB) Target User: Every User in Target Database with name ‘guest’ Now we have options for two evaluation modes: 1) On Demand and 2) On Schedule We will select On Demand in this example; however, you can change the mode to On Schedule through the drop down menu, and select the interval of the evaluation of the policy. Evaluate the Policies We have selected OnDemand as our policy evaluation mode. We will now evaluate by means of executing Evaluate policy. Click on Evaluate and it will give the following result: The result demonstrates that one of the databases has a policy violation. Username guest is enabled in AdventureWorks database. You can disable the guest user by running the following code in AdventureWorks database. USE AdventureWorks; REVOKE CONNECT FROM guest; Once you run above query, you can already evaluate the policy again. Notice that the policy violation is fixed now. You can change the method of the evaluation policy to On Schedule and validate policy on interval. You can check the history of the policy and detect the violation. Quiz I have created three conditions to check if the guest user has database access or not. Now I want to ask you: Is it possible to do the same with 2 conditions? If yes, HOW? If no, WHY NOT? Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Best Practices, CodeProject, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology Tagged: Policy Management

    Read the article

  • How-to filter table filter input to only allow numeric input

    - by frank.nimphius
    In a previous ADF Code Corner post, I explained how to change the table filter behavior by intercepting the query condition in a query filter. See sample #30 at http://www.oracle.com/technetwork/developer-tools/adf/learnmore/index-101235.html In this OTN Harvest post I explain how to prevent users from providing invalid character entries as table filter criteria to avoid problems upon re-querying the table. In the example shown next, only numeric values are allowed for a table column filter. To create a table that allows data filtering, drag a View Object – or a data collection of a Web Service or JPA business service – from the DataControls panel and drop it as a table. Choose the Enable Filtering option in the Edit Table Columns dialog so the table renders with the column filter boxes displayed. The table filter fields are created using implicit af:inputText components that need to be customized for you to apply a custom filter input component, or to change the input behavior. To change the input filter, so only a defined set of input keys is allowed, you need to change the default filter field with your own af:inputText field to which you apply an af:clientListener tag that filters user keyboard entries. For this, in the Oracle JDeveloper visual editor, select the column which filter you want to change and expand the column node in the Oracle JDeveloper Structure Window. Part of the column definition is the Column facet node. Expand the facets so you see the filter facet entry. The filter facet is grayed out as there is no custom facet defined. In a next step, open theComponent Palette (ctrl+shift+P) and drag an Input Text component onto the facet. This demarks the first part in the filter customization. To make the custom filter component work, you need to map the af:inputText component value property to the ADF filter criteria that is exposed in the Expression Builder. Open the Expression Builder for the filter input component value property by clicking the arrow icon to its right. In the Expression Builder expand the JSP Objects | vs | filterCriteria node to select the attribute name represented by the table column. The vs entry is the name of a variable that is defined on the table and that grants you access to the table attributes. Now that the filter works as before – though using a custom filter input component – you can add the af:clientListener tag to your custom filter component – af:inputText – to call out to JavaScript when users type in the column filter field Point the client filter method property to a JavaScript function that you reference or add through using the af:resource tag and set the type property value to keyDown. <af:document id="d1">     <af:resource type="javascript" source="/js/filterHandler.js"/> … The filter definition looks as shown below <af:inputText label="Label 1" id="it1"                         value="#{vs.filterCriteria.Employe        <af:clientListener method="suppressCharacterInput"                                     type="keyDown"/> </af:inputText> The JavaScript code that you can use to either filter character inputs or numeric inputs is shown below. Just store this code in an external JavaScript (.js) file and reference it from the af:resource tag. //Allow numbers, cursor control keys and delete keys function suppressCharacterInput(evt) {     var _keyCode = evt.getKeyCode();     var _filterField = evt.getCurrentTarget();     var _oldValue = _filterField.getValue();     if (!((_keyCode < 57) ||(_keyCode > 96 && _keyCode < 105))) {         _filterField.setValue(_oldValue);         evt.cancel();     } } //Allow characters, cursor control keys and delete keys function suppressNumericInput(evt) {  var _keyCode = evt.getKeyCode();  var _filterField = evt.getCurrentTarget();  var _oldValue = _filterField.getValue();  //check for numbers  if ((_keyCode < 57 && _keyCode > 47) ||      (_keyCode > 96 && _keyCode < 105)){     _filterField.setValue(_oldValue);     evt.cancel();   } } But what if browsers don't allow JavaScript ? Don't worry about this. If browsers would not support JavaScript then ADF Faces as a whole would not work and you had a different problem.

    Read the article

  • Wildcards!

    - by Tim Dexter
    Yes, its been a while, Im sorry, mumble, mumble ... no excuses. Well other than its been, as my son would say 'hecka busy.' On a brighter note I see Kan has been posting some cool stuff in my absence, long may he continue! I received a question today asking about using a wildcard in a template, something like: <?if:INVOICE = 'MLP*'?> where * is the wildcard Well that particular try does not work but you can do it without building your own wildcard function. XSL, the underpinning language of the RTF templates, has some useful string functions - you can find them listed here. I used the starts-with function to achieve a simple wildcard scenario but the contains can be used in conjunction with some of the others to build something more sophisticated. Assume I have a a list of friends and the amounts of money they owe me ... Im very generous and my interest rates a pretty competitive :0) <ROWSET> <ROW> <NAME>Andy</NAME> <AMT>100</AMT> </ROW> <ROW> <NAME>Andrew</NAME> <AMT>60</AMT> </ROW> <ROW> <NAME>Aaron</NAME> <AMT>50</AMT> </ROW> <ROW> <NAME>Alice</NAME> <AMT>40</AMT> </ROW> <ROW> <NAME>Bob</NAME> <AMT>10</AMT> </ROW> <ROW> <NAME>Bill</NAME> <AMT>100</AMT> </ROW> Now, listing my friends is easy enough <for-each:ROW> <NAME> <AMT> <end for-each> but lets say I just want to see all my friends beginning with 'A'. To do that I can use an XPATH expression to filter the data and tack it on to the for-each expression. This is more efficient that using an 'if' statement just inside the for-each. <?for-each:ROW[starts-with(NAME,'A')]?> will find me all the A's. The square braces denote the start of the XPATH expression. starts-with is the function Im calling and Im passing the value I want to check i.e. NAME and the string Im looking for. Just substitute in the characters you are looking for. You can of course use the function in a if statement too. <?if:starts-with(NAME,'A')?><?attribute@incontext:color;'red'?><?end if?> Notice I removed the square braces, this will highlight text red if the name begins with an 'A' You can even use the function to do conditional calculations: <?sum (AMT[starts-with(../NAME,'A')])?> Sum only the amounts where the name begins with an 'A' Notice the square braces are back, its a function we want to apply to the AMT field. Also notice that we need to use ../NAME. The AMT and NAME elements are at the same level in the tree, so when we are at the AMT level we need the ../ to go up a level to then come back down to test the NAME value. I have built out the above functions in a sample template here. Huge prizes for the first person to come up with a 'true' wildcard solution i.e. if NAME like '*im*exter* demand cash now!

    Read the article

  • Telerik is First to Announce Support for Microsoft Silverlight Analytics Framework

    Yesterday at MIX 10 conference Microsoft announced the Microsoft Silverlight Analytics Framework Beta. The Silverlight Analytics Framework (SAF) is a new open-source framework to allow designers and developers to integrate web analytics into Silverlight applications in a consistent manner. Supporting out-of-browser and offline scenarios, Microsoft built this framework in conjunction with a number of web analytics services and control vendors to support multiple analytics services simultaneously without degrading application performance. Because the SAF is enabled as a set of behaviors in Microsoft Expression Blend, designers and developers can visually instrument their designs and configure A/B testing rapidly without writing any code. Telerik is proud to be the first control vendor to support the Silverlight Analytics Framework. RadControls for Silverlight can be used with the framework out of the box. The suite offers Silverlight Analytics Framework handlers and behavior, helping developers to fine tune the values sent to the analytics providers. Because the analytics framework is using the Managed Extensibility Framework (MEF) for composition, you don't need to change the way you use the controls to benefit from the Telerik handlers. Just add a reference to the Telerik assemblies that contains the handlers. Here is the code that you need to declare to use RadTreeView: <UserControl x:Class="Telerik.SLAF.MainPage"         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"         xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"         xmlns:ga="clr-namespace:Google.WebAnalytics;assembly=Google.WebAnalytics"         xmlns:sa="clr-namespace:Microsoft.WebAnalytics.Behaviors;assembly=Microsoft.WebAnalytics.Behaviors"         xmlns:ic="clr-namespace:Microsoft.Expression.Interactivity.Core;assembly=Microsoft.Expression.Interactions"         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"         xmlns:telerikNavigation="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Navigation">        <Grid x:Name="LayoutRoot">         <i:Interaction.Behaviors>             <ga:GoogleAnalytics ProfileId="--Your GA ProfileId" Category="Demo" />         </i:Interaction.Behaviors>         <telerikNavigation:RadTreeView>             <i:Interaction.Triggers>                 <i:EventTrigger EventName="SelectionChanged">                     <sa:TrackAction />                 </i:EventTrigger>             </i:Interaction.Triggers>             <telerikNavigation:RadTreeViewItem Header="Item1">             </telerikNavigation:RadTreeViewItem>             <telerikNavigation:RadTreeViewItem Header="Item2" />             <telerikNavigation:RadTreeViewItem Header="Item3" />         </telerikNavigation:RadTreeView>     </Grid> </UserControl> Download the Telerik Microsoft Silverlight Analytics Framework Handlers and the sample project. This is our first Beta release - please drop us a line with any feedback you have or even better if you are at MIX10 - come visit us at the booth in the "Commons" hall so we can discuss it in person. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

    Read the article

  • ODI 12c - Aggregating Data

    - by David Allan
    This posting will look at the aggregation component that was introduced in ODI 12c. For many ETL tool users this shouldn't be a big surprise, its a little different than ODI 11g but for good reason. You can use this component for composing data with relational like operations such as sum, average and so forth. Also, Oracle SQL supports special functions called Analytic SQL functions, you can use a specially configured aggregation component or the expression component for these now in ODI 12c. In database systems an aggregate transformation is a transformation where the values of multiple rows are grouped together as input on certain criteria to form a single value of more significant meaning - that's exactly the purpose of the aggregate component. In the image below you can see the aggregate component in action within a mapping, for how this and a few other examples are built look at the ODI 12c Aggregation Viewlet here - the viewlet illustrates a simple aggregation being built and then some Oracle analytic SQL such as AVG(EMP.SAL) OVER (PARTITION BY EMP.DEPTNO) built using both the aggregate component and the expression component. In 11g you used to just write the aggregate expression directly on the target, this made life easy for some cases, but it wan't a very obvious gesture plus had other drawbacks with ordering of transformations (agg before join/lookup. after set and so forth) and supporting analytic SQL for example - there are a lot of postings from creative folks working around this in 11g - anything from customizing KMs, to bypassing aggregation analysis in the ODI code generator. The aggregate component has a few interesting aspects. 1. Firstly and foremost it defines the attributes projected from it - ODI automatically will perform the grouping all you do is define the aggregation expressions for those columns aggregated. In 12c you can control this automatic grouping behavior so that you get the code you desire, so you can indicate that an attribute should not be included in the group by, that's what I did in the analytic SQL example using the aggregate component. 2. The component has a few other properties of interest; it has a HAVING clause and a manual group by clause. The HAVING clause includes a predicate used to filter rows resulting from the GROUP BY clause. Because it acts on the results of the GROUP BY clause, aggregation functions can be used in the HAVING clause predicate, in 11g the filter was overloaded and used for both having clause and filter clause, this is no longer the case. If a filter is after an aggregate, it is after the aggregate (not sometimes after, sometimes having).  3. The manual group by clause let's you use special database grouping grammar if you need to. For example Oracle has a wealth of highly specialized grouping capabilities for data warehousing such as the CUBE function. If you want to use specialized functions like that you can manually define the code here. The example below shows the use of a manual group from an example in the Oracle database data warehousing guide where the SUM aggregate function is used along with the CUBE function in the group by clause. The SQL I am trying to generate looks like the following from the data warehousing guide; SELECT channel_desc, calendar_month_desc, countries.country_iso_code,       TO_CHAR(SUM(amount_sold), '9,999,999,999') SALES$ FROM sales, customers, times, channels, countries WHERE sales.time_id=times.time_id AND sales.cust_id=customers.cust_id AND   sales.channel_id= channels.channel_id  AND customers.country_id = countries.country_id  AND channels.channel_desc IN   ('Direct Sales', 'Internet') AND times.calendar_month_desc IN   ('2000-09', '2000-10') AND countries.country_iso_code IN ('GB', 'US') GROUP BY CUBE(channel_desc, calendar_month_desc, countries.country_iso_code); I can capture the source datastores, the filters and joins using ODI's dataset (or as a traditional flow) which enables us to incrementally design the mapping and the aggregate component for the sum and group by as follows; In the above mapping you can see the joins and filters declared in ODI's dataset, allowing you to capture the relationships of the datastores required in an entity-relationship style just like ODI 11g. The mix of ODI's declarative design and the common flow design provides for a familiar design experience. The example below illustrates flow design (basic arbitrary ordering) - a table load where only the employees who have maximum commission are loaded into a target. The maximum commission is retrieved from the bonus datastore and there is a look using employees as the driving table and only those with maximum commission projected. Hopefully this has given you a taster for some of the new capabilities provided by the aggregate component in ODI 12c. In summary, the actions should be much more consistent in behavior and more easily discoverable for users, the use of the components in a flow graph also supports arbitrary designs and the tool (rather than the interface designer) takes care of the realization using ODI's knowledge modules. Interested to know if a deep dive into each component is interesting for folks. Any thoughts? 

    Read the article

  • Building a Repository Pattern against an EF 5 EDMX Model - Part 1

    - by Juan
    I am part of a year long plus project that is re-writing an existing application for a client.  We have decided to develop the project using Visual Studio 2012 and .NET 4.5.  The project will be using a number of technologies and patterns to include Entity Framework 5, WCF Services, and WPF for the client UI.This is my attempt at documenting some of the successes and failures that I will be coming across in the development of the application.In building the data access layer we have to access a database that has already been designed by a dedicated dba. The dba insists on using Stored Procedures which has made the use of EF a little more difficult.  He will not allow direct table access but we did manage to get him to allow us to use Views.  Since EF 5 does not have good support to do Code First with Stored Procedures, my option was to create a model (EDMX) against the existing database views.   I then had to go select each entity and map the Insert/Update/Delete functions to their respective stored procedure. The next step after I had completed mapping the stored procedures to the entities in the EDMX model was to figure out how to build a generic repository that would work well with Entity Framework 5.  After reading the blog posts below, I adopted much of their code with some changes to allow for the use of Ninject for dependency injection.http://www.tcscblog.com/2012/06/22/entity-framework-generic-repository/ http://www.tugberkugurlu.com/archive/generic-repository-pattern-entity-framework-asp-net-mvc-and-unit-testing-triangle IRepository.cs public interface IRepository : IDisposable where T : class { void Add(T entity); void Update(T entity, int id); T GetById(object key); IQueryable Query(Expression> predicate); IQueryable GetAll(); int SaveChanges(); int SaveChanges(bool validateEntities); } GenericRepository.cs public abstract class GenericRepository : IRepository where T : class { public abstract void Add(T entity); public abstract void Update(T entity, int id); public abstract T GetById(object key); public abstract IQueryable Query(Expression> predicate); public abstract IQueryable GetAll(); public int SaveChanges() { return SaveChanges(true); } public abstract int SaveChanges(bool validateEntities); public abstract void Dispose(); } One of the issues I ran into was trying to do an update. I kept receiving errors so I posted a question on Stack Overflow http://stackoverflow.com/questions/12585664/an-object-with-the-same-key-already-exists-in-the-objectstatemanager-the-object and came up with the following hack. If someone has a better way, please let me know. DbContextRepository.cs public class DbContextRepository : GenericRepository where T : class { protected DbContext Context; protected DbSet DbSet; public DbContextRepository(DbContext context) { if (context == null) throw new ArgumentException("context"); Context = context; DbSet = Context.Set(); } public override void Add(T entity) { if (entity == null) throw new ArgumentException("Cannot add a null entity."); DbSet.Add(entity); } public override void Update(T entity, int id) { if (entity == null) throw new ArgumentException("Cannot update a null entity."); var entry = Context.Entry(entity); if (entry.State == EntityState.Detached) { var attachedEntity = DbSet.Find(id); // Need to have access to key if (attachedEntity != null) { var attachedEntry = Context.Entry(attachedEntity); attachedEntry.CurrentValues.SetValues(entity); } else { entry.State = EntityState.Modified; // This should attach entity } } } public override T GetById(object key) { return DbSet.Find(key); } public override IQueryable Query(Expression> predicate) { return DbSet.Where(predicate); } public override IQueryable GetAll() { return Context.Set(); } public override int SaveChanges(bool validateEntities) { Context.Configuration.ValidateOnSaveEnabled = validateEntities; return Context.SaveChanges(); } #region IDisposable implementation public override void Dispose() { if (Context != null) { Context.Dispose(); GC.SuppressFinalize(this); } } #endregion IDisposable implementation } At this point I am able to start creating individual repositories that are needed and add a Unit of Work.  Stay tuned for the next installment in my path to creating a Repository Pattern against EF5.

    Read the article

< Previous Page | 74 75 76 77 78 79 80 81 82 83 84 85  | Next Page >