Search Results

Search found 15051 results on 603 pages for 'meta programming'.

Page 483/603 | < Previous Page | 479 480 481 482 483 484 485 486 487 488 489 490  | Next Page >

  • Atoms and references

    - by StackedCrooked
    According to the book Programming Clojure refs manage coordinated, synchronous changes to shared state and atoms manage uncoordinated, synchronous changes to shared state. If I understood correctly "coordinated" implies multiple changes are encapsulated as one atomic operation. If that is the case then it seems to me that coordination only requires using a dosync call. For example what is the difference between: (def i (atom 0)) (def j (atom 0)) (dosync (swap! i inc) (swap! j dec)) and: (def i (ref 0)) (def j (ref 0)) (dosync (alter i inc) (alter j dec))

    Read the article

  • Make a usable Join relationship with LINQ on top of a database CSV design error

    - by jdk
    I'm looking for a way to fix and/or abstract away a comma-separated values (CSV) list in a database field in order to reconstruct a usable relationship such that I can properly join the two tables below and query them using LINQ and its Join method. Following is a sample showing the Person table and CsvArticleIds field having a CSV value to represent a one-to-many association with Article records. TABLE [dbo].[Person] Id Name CsvArticleIds -- ---------- -------- 1 Joe "15,22" 5 Ed "22" 10 Arnie "8,15,22" ^^^(Of course a link table should have been created; nonetheless the relationship with articles is trapped inside that list of CSV values.) TABLE [dbo].[Article] Id Title -- ---------- 8 Beginning C# 15 A Historic look at Programming in the 90s 22 Gardening in January Additional Info the fix can be at any level: C#.NET or SQL Server something easy because I will be repeating the solution for many other CSV values in other tables. Elegant is nice too. not looking for efficiency because this is part of a one-time data migration task and can take as long as it wants to run.

    Read the article

  • Ideas for building vulnerabilities into your site?

    - by Jaco Pretorius
    I'm trying to create a programming challenge that would require developers to hack into the MVC site I create. The idea is obviously to teach them about preventing these types of attacks. The current idea I have is to build multiple vulnerabilities into the site - but the second vulnerability would require the first to be completed, etc. So I was thinking the first could be a sql injection attack, the second would require a modified GET request, etc. Exploiting the final vulnerability would reveal a specific piece of information which is proof that you have completed the entire challenge. This will not be deployed on a public site - it's simply a learning tool for developers at my company. I'm not looking for MVC-specific vulnerabilities - I'm simply using MVC because it allows me to work with the 'raw' HTML. Any ideas on the different vulnerabilities I can use?

    Read the article

  • Methods for making R plots look like Excel plots?

    - by brianjd
    I've been poking around with R graphical parameters trying to make my plots look a little more professional (e.g., las=1, bty="n" usually help). But not quite there. Started playing with tikzDevice. A huge improvement! Amazing how much better things look when the font sizes and styles in the figure match those of the surrounding document. Still, not quite there. What I'm ultimately looking for are those professional gradient shading, rounded corners, and shadow effects found in MS Excel plots. I know they're probably considered chart junk, but I like them. They're just nice looking. Q: How can I get these effects into my R plots? Do people usually just export to Inkscape and doodle over there? It would be nice if there were a literate programming approach. Is there an R package that handles these effects outright?

    Read the article

  • Noob Droid Question regarding random number

    - by Pete Herbert Penito
    Brand new to droid programming, but would love to learn as much as possible, so I finally got my emulator working correctly, I even got a hello world button to work, I'm attempting to make this button display a random number, I've googled this and came up with this code: Random generator = new Random(); int n = generator.nextInt(n); I fixed the Random function by including some Random java utility. I'm assuming this code above goes in the .java file of the project, so my button code looks as follows (tested and works): PopUpText.makeText(v.getContext(), "Hello World", PopUpText.LENGTH_LONG).show(); I figured I could replace "Hello World" with n to display the number in the box, however the following error is stopping the compile: The local variable n may not have been initialized Any ideas why this is happening? Any advice would be hugely appreciated.

    Read the article

  • Why "do...while" does not exist in F#

    - by Kev
    I cannot find "do...while..." I have to code like this: let bubbleSort a= let n = Array.length a let mutable swapped = true let mutable i = 0 while swapped do swapped <- false for j = 0 to n-i-2 do if a.[j] > a.[j+1] then let t = a.[j] a.[j] <- a.[j+1] a.[j+1] <- t swapped <- true i <- i+1 The code is bad without "do...while". Sadly, "break/continue" are also not available. Is F# not suitable for non-functional-programming?

    Read the article

  • Calculating terrain height in 3d-space

    - by Jonas B
    Hi I'm diving into 3d programming a bit and am currently learning by writing a procedural terrain generator that generates terrain based on a heightmap. I would also want to implement some physics and my first attempt at terrain collision was by simply checking the current position vs the heightmap. This however wont work well against small objects as you'd have to calculate the height by taking the heightdifference of the nearest vertices of the object and doing this every colision check is pretty slow. Beleive me I tried googling for it but there's simply so much crap and millions of blogs posting ripped-of newbie tutorials everywhere with basically no real information on the subject, I can't find anything that explains it or even names any generally used techniques. I'm not asking for code or a complete solution, but if anyone knows a particular technique good for calculating a high-res heightmap out of the already generated and smoothed terrain I would be very happy as I could look into it further when I know what I'm looking for. Thanks

    Read the article

  • PHP - Frameworks, ORM, Encapsulation.

    - by Ian
    Programming languages/environments aside, are there many developers who are using a framework in PHP, ORM and still abide by encapsulation for the DAL/BLL? I'm managing a team of a few developers and am finding that most of the frameworks require me to do daily code inspection because my developers are using the built in ORM. Right now, I've been using a tool to generate the classes and CRUD myself, with an area for them to write additional queries/functions. What's been happening though, is they are creating vulnerabilities by not doing proper checks on data permission, or allowing the key fields to be manipulated in the form. Any suggestions, other than get a new team and a new language (I've seen Python/Ruby frameworks have the same issues).

    Read the article

  • IsValidLocale returns FALSE - how to overcome this?

    - by sharptooth
    When run on a Spanish version of Windows XP my program invokes LANGID langId = (LANGID) MAKELANGID( LANG_ENGLISH, SUBLANG_DEFAULT ); LCID locale = MAKELCID( language, SORT_DEFAULT ); BOOL isValid = IsValidLocale( locale, LCID_INSTALLED ); IsValideLocale() return FALSE when asked about English locale. Obviously something must be tuned in Windows to change this behaviour. What exactly should I do? I understand that it's not completely a programming question but rather a deployment question. Still I think it will be better off here than anywhere else.

    Read the article

  • Teaching a mainframe COBOL programmer Java?

    - by Jared
    I’m trying to help someone learn Java who’s only programming experience is COBOL on the mainframe. I was wondering if anyone knew any good resources for object oriented concepts. I learned how to program with C++ so just understand the theory behind basic OOP. I’m more concerned about a way to get the basic concepts across, such as encapsulation and inheritance rather then Java syntax. I think it’d be better to teach the concepts of OOP then a language rather then trying to cram both a new language and paradigm in at the same time. Does anyone have any resources or ideas that could help this person learn OOP followed by Java?

    Read the article

  • Are there any easy ways to generate OpenGL code for drawing shapes from a GUI?

    - by Sam152
    I have enjoyed learning to use OpenGL under the context of games programming, and I have experimented with creating small shapes. I'm wondering if there are any resources or apps that will generate code similar to the following with a simple paint-like interface. glColor3f(1.0, 0.0, 0.0); glBegin(GL_LINE_STRIP); glVertex2f(1, 0); glVertex2f(2, 3); glVertex2f(4, 5); glEnd(); I'm having trouble thinking of the correct dimensions to generate shapes and coming up with the correct co-ordinates.

    Read the article

  • Is it secure to use malloc?

    - by Felix Guerrero
    Somebody told me that allocating with malloc is not secure anymore, I'm not a C/C++ guru but I've made some stuff with malloc and C/C++. Does anyone know about what risks I'm into? Quoting him: [..] But indeed the weak point of C/C++ it is the security, and the Achilles' heel is indeed malloc and the abuse of pointers. C/C++ it is a well known insecure language. [..] There would be few apps in what I would not recommend to continue programming with C++."

    Read the article

  • Basic PHP question for Drupal Views theming

    - by oalo
    My PHP and programming knowledge is extremely basic, so this is probably a dumb question: I am theming a View in Drupal 6, and I want to add an id with a consecutive number to each item in the view (first item would have the id #item1, the second #item2, etc). I am customizing the style output (views-view-unformatted--MYVIEWNAME.tpl.php) and the row style output (views-view-fields--MYVIEWNAME.tpl.php), and I want to add a counter variable in the foreach loop in the style output tpl, and then use that variable in the row style output tpl, but the last one is not recognizing the variable. It does not give me any errors, but doesnt print the number. I understand this has probably something to do with variables visibility, how can I declare the counter variable in the style .tpl so I can the use it in the row style .tpl? Thank you

    Read the article

  • Succinct code over verbose?

    - by WeNeedAnswers
    With C# becoming more and more declarative and becoming the new Swiss army knife of Programming. Is it better to be succinct thus reducing the actual code base, or long winded but verbose. Is there a performance issue with succinct or does being succinct improve performance because your putting more of your code in the hands of the compiler. (LINQ being an example when used correctly). I know that verbosity should override succinct where code would become less readable, but is this a good idea when your style could affect the performance.

    Read the article

  • Straight Java/Groovy versus ETL tool (Talend/etc) - what libraries would you use?

    - by Alex R
    Assume you have a small project which on the surface looks like a good match for an ETL tool like Talend. But assume further, that you have never used Talend and furthermore, you do not trust "visual programming" tools in general and would rather code everything the old fashioned way (text on a nice IDE!) with the help of an appropriate language & support libraries. What are some language patterns & support libraries that could help you stay away from the ETL tool temptation/trap?

    Read the article

  • Learning to think in the Object Oriented Way

    - by SpikETidE
    Hi Everyone.... I am a programmer trying to learn to code in the object oriented paradigm... I mainly work with PHP and i thought of learning the zend framework... So, felt I need to learn to code in OO PHP.... The problem is, having done code using functions for quite a long time, i just can't get my head to think in the OO way.... Also felt that probably I am not the only one facing this problem since the beginning of time... So, how did you people learn object oriented programming... especially how did you succeed in "unlearning" to code using functions... and learn to see you code as objects...? Is there any good resource books or sites where one could find help...?? Thanks for sharing your knowledge and experiences...

    Read the article

  • Style of if: to nest or not to nest

    - by Marco
    A colleague of mine and me had a discussion about the following best-practice issue. Most functions/methods start with some parameter checking. I advocate the following style, which avoids nesting. if (parameter one is ugly) return ERROR; if (parameter two is nonsense || it is raining) return ERROR; // do the useful stuff return result; He, who comes from a more functional/logic programming background, prefers the following, because it reduces the number of exit points from the function. if (parameter one is ok) { if (parameter two is ok && the sun is shining) { // do the useful stuff return result } } return ERROR; Which one would you prefer and why?

    Read the article

  • How can i determine the version of the Windows SDK installed on my computer?

    - by NuclearCheese781
    Hello everyone :) I've very recently decided to teach myself c++ and win32 programming after learning vb.net, and i've got a very simple question: How can I determine what version of the Windows SDK is installed on my computer? I'm asking so I can install the latest version if it isn't installed allready, before i start playing around with c++. I'm using Microsoft Visual Studio 2008 SP1 as my IDE. (I spent 10 minutes using Google to search for an answer, but I couldn't find one) If anyone could help me, it would be very much appreciated. Matt.

    Read the article

  • For what programs are Objective C and Ruby ideal on the Mac?

    - by Kurt
    Hi, as a Mac outsider it seems that two popular programming languages on the Mac appear to be Objective C and Ruby. From what I understand the main API Cocoa seems to be written in and optimized for Objective C, but it is also possible to use Ruby for that. Are there different areas where each language is ideal, for example, I could imagine Objective C could be ideal for a GUI layer, or standalone desktop app, and Ruby could be good for web services etc. What about classic business logic, or data access layers? What language would be a good choice for a library of services for example? Can we write a library in one language and link to it from a main program written in the other language? If I wanted to write a layered enterprise application using domain driven design and dependency injection which languages could support each concerns? Are things like DDD and DI common amongst Mac devs? Just a curious outsider.

    Read the article

  • Converting a constantly changing scalar value to a changing interval or frequency

    - by eco_bach
    Although I'm coding in Objective C, this is more of a general programming question. What is the best way to convert a constantly changing scalar value to a changing interval or frequency? Right now every time the scalar value changes I am destroying the NSInterval ie [self.myTimer invalidate]; self.myTimer = nil; and creating a new one, but this seems like a VERY expensive way to achieve my goal, since the changing scalar value in my case represents the horizontal velocity of a swipe. For a rough analogy, think of the speed of a swipe being reflected in a visual metronome, the faster you swipe, the higher(shorter interval) the frequency of the metronome.

    Read the article

  • Advice about a good Java book?

    - by camac1
    Hi people, I am new to Java but have experience programming in C/C++/C#. I wanted to learn Java SE 6 first before moving to Java EE 6. After making some research online for appropriate Java SE 6 books, I found that these are appropriate for me to get an excellent idea of Java SE 6: 1) Head First Java, 2nd Edition 2) An Intermediate Level Book <----------- 3) Effective Java (2nd Edition) 4) Java Concurrency in Practice 5) Java Generics and Collections 6) Java Concise Reference Series: Swing And AWT 7) Java Reflection in Action However, I am having trouble choosing an Intermediate Level Book which will provide me with breadth and depth in Java SE 6. I was thinking about the book "Thinking in Java (4th Edition)"....Unfortunately, its deals with Java SE 5 and not the latest version. Could anybody please advice me an intermediate level book which could provide me with breadth and depth in Java SE 6. Regards

    Read the article

  • Java Program Design Layout Recommendations?

    - by Leebuntu
    I've learned enough to begin writing programs from scratch, but I'm running into the problem of not knowing how to design the layout and implementation of a program. To be more precise, I'm having difficulty finding a good way to come up with an action plan before I dive in to the programming part. I really want to know what classes, methods, and objects I would need beforehand instead of just adding them along the way. My intuition is leading me to using some kind of charting software that gives a hierarchal view of all the classes and methods. I've been using OmniGraffle Pro and while it does seem to work somewhat, I'm still having trouble planning out the program in its entirety. How should I approach this problem? What softwares out there are available to help with this problem? Any good reads out there on this issue? Thanks so much! Edit: Oh yeah, I'm using Eclipse and I code mainly in Java right now.

    Read the article

  • how sort recursively by maximum fileze and counts files type?

    - by user599395
    Hello! I'm beginner in bash programming. I want to display head -n $1 results of sorting files by size in /etc/*. The problem is that at final search, I must know how many directories and files has processed. I compose following code: #!/bash/bin let countF=0; let countD=0; for file in $(du -sk /etc/* |sort +0n | head $1); do if [ -f "file" ] then echo $file; let countF=countF+1; else if [ -d "file" ] then let countD=countD+1; fi done echo $countF echo $countD I have errors at execution. How use find with du, because I must search recursively?

    Read the article

  • setNeedsDisplayInRect: paints a white rectangle only

    - by Ion Tichy
    Hi, I'm still a little fresh to CoreGraphics programming, so please bear with me. I'm trying to write an application, which allows the user to rub stuff off an image with the finger. I have the basic functionality nailed down, but the result is sluggish since the screen is redrawn completely every time a touch is rendered. I did some research and found out that I can refresh only a portion of the screen using UIView's setNeedsDisplayInRect: method. This does call drawRect: as expected, however everything I draw in the drawRect: following the setNeedsDisplayInRect: is ignored. Instead, the area in the rect parameter is simply filled with white. No matter what I draw inside, all I end up with is a white rectangle. In essence, this is what I do: 1) when user touches screen, this touch is rendered into a mask 2) when the drawRect: is called, the image is masked with that mask There must be something simple I'm overlooking, surely?

    Read the article

  • Need example of how to create/manipulate image pixel data with iPhone SDK

    - by whiskeyspider
    Looking for a simple example or link to a tutorial. Say I have a bunch of values stored in an array. I would like to create an image and update the image data from my array. Assume the array values are intensity data and will be updating a grayscale image. Assume the array values are between 0 and 255 -- or that I will convert it to that range. This is not for purposes of animation. Rather the image would be updated based on user interaction. This is something I know how to do well in Java, but am very new to iPhone programming. I've googled some information about CGImage and UIImage -- but am confused as to where to start. Any help would be appreciated.

    Read the article

< Previous Page | 479 480 481 482 483 484 485 486 487 488 489 490  | Next Page >