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  • What are some easy techniques to scan books for new information?

    - by aditya menon
    I find it irresistible to keep purchasing cheap programming and technical e-books in fields such as Drupal, PHP, etc., and also compulsively download free material made available such as those from Microsoft's developer blog... The main problem with the large library I've developed is that there are many chapters (especially the first few) in these books packed with information I already know, but with helpful tidbits hidden in between. The logical step would be to skip those chapters and read the ones I don't seem to know anything about, but I'm afraid I may lose out on really important information this way. But naturally it is tedious to have to read about variables, functions and objects all over again when you are trying to know more about the Registry pattern, for example. It's hard to research on the net for this, because my question itself seems vague and difficult to formulate into a single search query. I need people-advice - what do you do in this situation?

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  • Dual Inspection / Four Eyes Principle

    - by Ralf
    I have the requirement to implement some kind of dual inspection or four-eyes principle as a feature of my software, meaning that every change of an object done by user A has to be checked by user B. A trivial example would be a publishing system where an author writes an article and another has to proofread it before it is published. I am a little bit surprised that you find nearly nothing about it on the net. No patterns, no libraries (besides cibet), no workflow solutions etc. Is this requirement really so uncommon? Or am I searching for the wrong terms? I am not looking for a specific solution. More for a pattern or best practice approach. Update: the above example is really trivial. Let's add some more complexity to it. The article has been published, but it now needs an update. Putting the article offline for the update is not an option, but the update has to be proof read, too.

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  • Memento with optional state?

    - by Korey Hinton
    EDIT: As pointed out by Steve Evers and pdr, I am not correctly implementing the Memento pattern, my design is actually State pattern. Menu Program I built a console-based menu program with multiple levels that selects a particular test to run. Each level more precisely describes the operation. At any level you can type back to go back one level (memento). Level 1: Server Type? [1] Server A [2] Server B Level 2: Server environment? [1] test [2] production Level 3: Test type? [1] load [2] unit Level 4: Data Collection? [1] Legal docs [2] Corporate docs Level 4.5 (optional): Load Test Type [2] Multi TIF [2] Single PDF Level 5: Command Type? [1] Move [2] Copy [3] Remove [4] Custom Level 6: Enter a keyword [setup, cleanup, run] Design States PROBLEM: Right now the STATES enum is the determining factor as to what state is BACK and what state is NEXT yet it knows nothing about what the current memento state is. Has anyone experienced a similar issue and found an effective way to handle mementos with optional state? static enum STATES { SERVER, ENVIRONMENT, TEST_TYPE, COLLECTION, COMMAND_TYPE, KEYWORD, FINISHED } Possible Solution (Not-flexible) In reference to my code below, every case statement in the Menu class could check the state of currentMemo and then set the STATE (enum) accordingly to pass to the Builder. However, this doesn't seem flexible very flexible to change and I'm struggling to see an effective way refactor the design. class Menu extends StateConscious { private State state; private Scanner reader; private ServerUtils utility; Menu() { state = new State(); reader = new Scanner(System.in); utility = new ServerUtils(); } // Recurring menu logic public void startPromptingLoop() { List<State> states = new ArrayList<>(); states.add(new State()); boolean redoInput = false; boolean userIsDone = false; while (true) { // get Memento from last loop Memento currentMemento = states.get(states.size() - 1) .saveMemento(); if (currentMemento == null) currentMemento = new Memento.Builder(0).build(); if (!redoInput) System.out.println(currentMemento.prompt); redoInput = false; // prepare Memento for next loop Memento nextMemento = null; STATES state = STATES.values()[states.size() - 1]; // get user input String selection = reader.nextLine(); switch (selection) { case "exit": reader.close(); return; // only escape case "quit": nextMemento = new Memento.Builder(first(), currentMemento, selection).build(); states.clear(); break; case "back": nextMemento = new Memento.Builder(previous(state), currentMemento, selection).build(); if (states.size() <= 1) { states.remove(0); } else { states.remove(states.size() - 1); states.remove(states.size() - 1); } break; case "1": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; case "2": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; case "3": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; case "4": nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); break; default: if (state.equals(STATES.CATEGORY)) { String command = selection; System.out.println("Executing " + command + " command on: " + currentMemento.type + " " + currentMemento.environment); utility.executeCommand(currentMemento.nickname, command); userIsDone = true; states.clear(); nextMemento = new Memento.Builder(first(), currentMemento, selection).build(); } else if (state.equals(STATES.KEYWORD)) { nextMemento = new Memento.Builder(next(state), currentMemento, selection).build(); states.clear(); nextMemento = new Memento.Builder(first(), currentMemento, selection).build(); } else { redoInput = true; System.out.println("give it another try"); continue; } break; } if (userIsDone) { // start the recurring menu over from the beginning for (int i = 0; i < states.size(); i++) { if (i != 0) { states.remove(i); // remove all except first } } reader = new Scanner(System.in); this.state = new State(); userIsDone = false; } if (!redoInput) { this.state.restoreMemento(nextMemento); states.add(this.state); } } } }

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  • For Programmers familiar with ACM API? Drawing Initials [closed]

    - by user71992
    Possible Duplicate: For Programmers familiar with ACM API? Drawing Initials I came across an exercise (in the book "The Art and Science of Java" by Eric Roberts) that requires using only GArc and GLine classes to create a lettering library which draws your initials on the canvas. This should be made independent of the GLabel class. I'd like to know the correct approach to use in solving this problem. I'm not sure what I have so far is good enough (I'm thinking it's too long). The questions requires that I use a good Top-Down approach. Here's my code so far: //Passes letters to GLetter objects and draws them on the canvas package artScienceJavaExercises.chapter8; import acm.program.*; //import acm.graphics.*; public class DrawInitials extends GraphicsProgram{ public void init(){ resize(400,400); } public void run(){ //String let = readLine("Letter?: "); letter = new GLetter("l"); add(letter, (getWidth()-letter.getWidth()*2)/2, (getHeight()-letter.getHeight())/2); add(new GLetter("o"), (letter.getX()+letter.getWidth()), letter.getY()); } private GLetter letter; } //GLetter Class package artScienceJavaExercises.chapter8; import acm.graphics.*; import java.awt.*; public class GLetter extends GCompound{ private static final int ONE_THIRD = 30; private static final int ROW_2_HEIGHT = 40; private GArc[] arc = new GArc[4]; private GLine[] line = new GLine[24]; public GLetter(String s){ line[0] = new GLine(0,0, ONE_THIRD, 0); line[1] = new GLine(ONE_THIRD,0, ONE_THIRD*2, 0); line[2] = new GLine(ONE_THIRD*2,0, ONE_THIRD*3, 0); line[3] = new GLine(0,0, 0,ONE_THIRD); line[4] = new GLine(ONE_THIRD,0, ONE_THIRD, ONE_THIRD); line[5] = new GLine(ONE_THIRD*2,0, ONE_THIRD*2, ONE_THIRD); line[6] = new GLine(ONE_THIRD*3,0, ONE_THIRD*3, ONE_THIRD); line[7] = new GLine(0,ONE_THIRD, ONE_THIRD*2, ONE_THIRD); line[8] = new GLine(ONE_THIRD,ONE_THIRD, ONE_THIRD*2, ONE_THIRD); line[9] = new GLine(ONE_THIRD*2,ONE_THIRD, ONE_THIRD*3, ONE_THIRD); line[10] = new GLine(0,ONE_THIRD, 0, ONE_THIRD+ROW_2_HEIGHT); line[11] = new GLine(ONE_THIRD, ONE_THIRD, ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT); line[12] = new GLine(ONE_THIRD*2,ONE_THIRD, ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT); line[13] = new GLine(ONE_THIRD*3,ONE_THIRD, ONE_THIRD*3, ONE_THIRD+ROW_2_HEIGHT); line[14] = new GLine(0, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT); line[15] = new GLine(ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT); line[16] = new GLine(ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*3, ONE_THIRD+ROW_2_HEIGHT); line[17] = new GLine(0, ONE_THIRD+ROW_2_HEIGHT, 0, ONE_THIRD*2+ROW_2_HEIGHT); line[18] = new GLine(ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD, ONE_THIRD*2+ROW_2_HEIGHT); line[19] = new GLine(ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*2, ONE_THIRD*2+ROW_2_HEIGHT); line[20] = new GLine(ONE_THIRD*3, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*3, ONE_THIRD*2+ROW_2_HEIGHT); line[21] = new GLine(0,ONE_THIRD*2+ROW_2_HEIGHT, ONE_THIRD, ONE_THIRD*2+ROW_2_HEIGHT); line[22] = new GLine(ONE_THIRD, ONE_THIRD*2+ROW_2_HEIGHT, ONE_THIRD*2, ONE_THIRD*2+ROW_2_HEIGHT); line[23] = new GLine(ONE_THIRD*2,ONE_THIRD*2+ROW_2_HEIGHT, ONE_THIRD*3, ONE_THIRD*2+ROW_2_HEIGHT); for(int i = 0; i<line.length; i++){ add(line[i]); line[i].setColor(Color.BLACK); line[i].setVisible(false); } arc[0] = new GArc(getWidth(), getHeight(), 106.699, 49.341); arc[1] = new GArc(getWidth(), getHeight(), 23.96, 49.341); arc[2] = new GArc(getWidth(), getHeight(), -23.96, -49.341); arc[3] = new GArc(0,0,getWidth(), getHeight(), -106.699, -49.341); for(int i = 0; i<arc.length; i++){ add(arc[i],0,0); arc[i].setColor(Color.BLACK); arc[i].setVisible(false); } paintLetter(s); } private void paintLetter(String s){ if (s.equalsIgnoreCase("l")){ turnOn(line[3]); turnOn(line[10]); turnOn(line[17]); turnOn(line[21]); turnOn(line[22]); turnOn(line[23]); } else if(s.equalsIgnoreCase("o")){ for(int i = 0; i<4; ++i){ turnOn(arc[i]); } turnOn(line[1]); turnOn(line[10]); turnOn(line[13]); turnOn(line[22]); } } private void turnOn(GObject g){ g.setVisible(true); } } I created a class (GLetter.java) with arrays for GArc and GLine objects. They are positioned in certain ways thereby turning certain Glines and/or GArcs on or off (changing visiblity) would create a pattern for a letter. This Gletter uses the if/else statements to determine which pattern to create - this makes me feel my code is too long. There is another class (DrawInitials.java) that simulates a GraphicsProgram and allows the user to pass certain letters as arguments to the GLetter object. I've used 'L' and 'O' as examples. However, I posted this because I'm not sure I'm using the right approach. That's why I need your help. I feel MY CODE IS TOO LONG! The code above is not the complete project...it only draws letters 'L' and 'O' for now.

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  • Filtering content from response body HTML (mod_security or other WAFs)

    - by Bingo Star
    We have Apache on Linux with mod_security as the Web App Firewall (WAF) layer. To prevent content injections, we have some rules that basically disable a page containing some text patterns from showing up at all. For example, if an HTML page on webserver has slur words (because some webmaster may have copied/pasted text without proofreading) the Apache server throws a 406 error. Our requirement now is a little different: we would like to show the page as regular 200, but if such a pattern is matched, we want to strip out the offending content. Not block the entire page. If we had a server side technology we could easily code for this, but sadly this is for a website with 1000s of static html pages. Another solution might have been to do a cronjob of find/replace strings and run them on folders en-masse, maybe, but we don't have access to the file system in this case (different department). We do have control over WAF or Apache rules if any. Any pointers or creative ideas?

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  • Allow user to SUDO a script without password.

    - by John Isaacks
    I have a php script with this: <?php #echo exec('whoami'); $output = shell_exec('bash /usr/local/svn/bash_repo/make-live'); echo "$output"; ?> The make-live script contains this: #!/bin/bash cd /var/www-cake sudo svn checkout file:///usr/local/svn/bash_repo/repo/ echo "Head revision has been pushed to live server" So the PHP user who is www-data needs to have nopasswd for that script. I am told I need to add: www-data ALL=NOPASSWD: /usr/local/svn/bash_repo/make-live To sudoers to allow this. First I run sudo visudo but I have no experience with vi so I try to open it in gedit with export EDITOR=gedit && sudo -E visudo which then just opens a sudoers.tmp file which is empty. I add the line and save it. But it doesn't do save. So I just try sudo visudo and I add the line right beneath this part: # User privilege specification root ALL=(ALL) ALL www-data ALL=NOPASSWD: /usr/local/svn/bash_repo/make-live I closed out sudoers and reopened to verify that it has saved. I even restart apache. I run the php file and it still doesn't work. What am I missing?

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  • Thoughts about MVC

    - by ayyash
    so i figured this one out, as a newcomer to the web development scene from the telecom biz, where we dealt with low level hardware API's, and a C++ fanboy, i tend to be bothered by automagical code, yes i appreciate the effort that went into it, and i certainly appreciate the luxury it provides to get more things done, but i just don't get it. so i decided to change that, and start investigating the new MVC based web apps, and at first it was like hitting a brick wall, i knew MVC from MFC days, so i'm familiar with the pattern, but i just couldn't get my head around the web version of it, till i came to realize the routing, is actually a separate feature to be inspected, much like understanding how LINQ works by better understanding anonymous objects. and so this article serve as an introduction to the following blogs where i share my views of how asp.net routing works, and then leverage that to the MVC level, and play around that field for a bit. as with most of my shared knowladge that may seem trivial to some, but i guess a newcomer's point of view can be useful for some folks out there.

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  • Cocos2d and Body with few collision shapes using chipmunk

    - by Eimantas
    I'm using Cocos2d (0.99.5) with chipmunk physics engine. Currently I'm trying to place a body into space which is combined from few circle shapes. Let's say I have a corresponding sprite image with displays atom (nucleus + 3 electrons around it. Something like this without orbit lines). In it's simplest form - only one circle shape at the center should be enough which would detect collisions from other objects with nucleus. Now I'd like to add other circle shapes for each electron. How can I do that? Now when I add those shapes to the body and add the body into chipmunk space - the shapes (together with the body/sprite) start flickering and spinning with no recognizable pattern (or reason for that matter).

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  • Ubuntu does not work with Nvidia drivers, gives random squares after logging in

    - by jimbo
    I tried installing both with wubi and by booting from a usb drive. After I tried both it was the same. Ubuntu tried to login, but after a while, a weird pattern with squarely shapes appeared. At one point, after using recovery mode and then the low graphics one (i don't remember how it was called exactly) i managed to get in. It still didn't display at correct resolution, and the mouse was invisible at times. However, after rebooting once, because i tried downloading the nvidia drivers, i didn't manage to get in again, so i have the same problem... I have no idea what to try to become unstuck. The main problem is that after the login, ubuntu crashes, with a screen full of randomly coloured squares. Should I just give up?

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  • Exposing warnings\errors from data objects (that are also list returned)

    - by Oren Schwartz
    I'm exposing Data objects via service oriented assembly (which on future usages might become a WCF service). The data object is tree designed, as well as formed from allot of properties.Moreover, some services return one objects, others retrieve a list of them (thus disables throwing exceptions). I now want to expose data flow warnings and wondering what's the best way to do it having to things to consider: (1) seperation (2) ease of access. On the one hand, i want the UI team to be able to access a fields warnings (or errors) without having them mapping the field names to an external source but on the other hand, i don't want the warnings "hanged" on the object itself (as i don't see it a correct design). I tought of creating a new type of wrapper for each field, that'll expose events and they'll have to register the one's they care about (but totally not sure) I'll be happy to hear your thoughts. Could you please direct me to a respectful design pattern ? what dp will do best here ? Thank you very much!

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  • Self-referencing anonymous closures: is JavaScript incomplete?

    - by Tom Auger
    Does the fact that anonymous self-referencing function closures are so prevelant in JavaScript suggest that JavaScript is an incomplete specification? We see so much of this: (function () { /* do cool stuff */ })(); and I suppose everything is a matter of taste, but does this not look like a kludge, when all you want is a private namespace? Couldn't JavaScript implement packages and proper classes? Compare to ActionScript 3, also based on EMACScript, where you get package com.tomauger { import bar; class Foo { public function Foo(){ // etc... } public function show(){ // show stuff } public function hide(){ // hide stuff } // etc... } } Contrast to the convolutions we perform in JavaScript (this, from the jQuery plugin authoring documentation): (function( $ ){ var methods = { init : function( options ) { // THIS }, show : function( ) { // IS }, hide : function( ) { // GOOD }, update : function( content ) { // !!! } }; $.fn.tooltip = function( method ) { // Method calling logic if ( methods[method] ) { return methods[ method ].apply( this, Array.prototype.slice.call( arguments, 1 )); } else if ( typeof method === 'object' || ! method ) { return methods.init.apply( this, arguments ); } else { $.error( 'Method ' + method + ' does not exist on jQuery.tooltip' ); } }; })( jQuery ); I appreciate that this question could easily degenerate into a rant about preferences and programming styles, but I'm actually very curious to hear how you seasoned programmers feel about this and whether it feels natural, like learning different idiosyncrasies of a new language, or kludgy, like a workaround to some basic programming language components that are just not implemented?

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  • Learning to optimize with Assembly

    - by niktehpui
    I am a second year student of Computer Games Technology. I recently finished my first prototype of my "kind" of own pathfinder (that doesn't use A* instead a geometrical approach/pattern recognition, the pathfinder just needs the knowledge about the terrain that is in his view to make decisions, because I wanted an AI that could actually explore, if the terrain is already known, then it will walk the shortest way easily, because the pathfinder has a memory of nodes). Anyway my question is more general: How do I start optimizing algorithms/loops/for_each/etc. using Assembly, although general tips are welcome. I am specifically looking for good books, because it is really hard to find good books on this topic. There are some small articles out there like this one, but still isn't enough knowledge to optimize an algorithm/game... I hope there is a modern good book out there, that I just couldn't find...

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  • Writing Large Portions Of Code Then Debugging?

    - by The Floating Brain
    Lately I have been writing a game engine, and I have been writing a lot of "foundation stuff" (standard interfaces, modules, a message system ect.), but I have noticed a pattern, a lot of the stuff is interdependent and I can not debug until everything is done, hence I do not debug for about 3 to 5 hours at a time. I am wondering if this is an acceptable practice for this part of the project, and if not, if anyone can give me some advice? -----Update-----: I downloaded some code metrics tools, and my programs cyclomatic complexity is 1.52 which as I understand it is good, and should correlate to high cohesion, if I am wrong please correct me/

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  • What php programmer should know?

    - by emchinee
    I've dig the database here and didn't found any answer for my question. What is a standard for a php programmer to know? I mean, literally, what group of language functions, mechanisms, variables should person know to consider oneself a (good) php programmer? (I know 'being good' is beyond language syntax, still I'm considering syntax of plain php only) To give an example what I mean: functions to control http sessions, cookies functions to control connection with databases functions to control file handling functions to control xml etc.. I omit phrases like 'security' or 'patterns' or 'framework' intentionally as it applies to every programming language. Hope I made myself clear, any input appreciated :) Note: Michael J.V. is right claiming that databases are independent from language, so to put my question more precisely and emphasise differences: Practises or security, are some ideas to implement (there is no 'Pattern' object with 'Decorator()' method, is there?) while using databases means knowing a mysqli and a set of its methods.

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  • What are some recommended video lectures for a non-CS student to prepare for the GRE CS subject test?

    - by aristos
    Well the title kinda explains all there is to explain. I'm a non-cs student and was preparing to apply PhD programs in applied mathematics. But for my senior thesis I've been reading lots of machine learning and pattern recognition literature and enjoying it a lot. I've taken lots of courses with statistics and stochastics content, which I think, would help me if I get accepted to a program with ML focus, but there are only two CS courses -introduction to programming- in my transcript and therefore I decided to take the CS subject test to increase my chances. Which courses do you think would be most essential to have a good result from CS subject test? I'm thinking of watching video lectures of them, so do you have any recommendations?

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  • How to create and administer multi-architecture PPAs?

    - by maxschlepzig
    I have a program that needs to be recompiled for every ubuntu version. Currently I am packaging it using Ubuntu's PPA just for the current distribution. Eventually, I have to provide packages for the previous ubuntu version. I am not sure how to accomplish this. How does the Ubuntu PPA build server works - does it just look at the distribution field in the most current changelog entry (in the debian/changelog file) to determine for what distribution the package should be build? The debian specification allows to add multiple distributions into the distribution field. But this does not seam to help me. Some ubuntu documents talk about encoding the distribution name into the version number (in the debian changelog file). But how does this work in practice? A new version of the program is available, then what? Do I add for each distribution a new changelog entry and the PPA buildserver builds automatically for each distribution new packages after dput'ing it up? Or does the PPA buildserver just looks at the first changelog entry?

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  • How Service Component Architecture (SCA) Can Be Incorporated Into Existing Enterprise Systems

    After viewing Rob High’s presentation “The SOA Component Model” hosted on InfoQ.com, I can foresee how Service Component Architecture (SCA) can be incorporated in to an existing enterprise. According to IBM’s DeveloperWorks website, SCA is a set of conditions which outline a model for constructing applications/systems using a Service-Oriented Architecture (SOA). In addition, SCA builds on open standards such as Web services. In the future, I can easily see how some large IT shops could potently divide development teams or work groups up into Component/Data Object Groups, and Standard Development Groups. The Component/Data Object Group would only work on creating and maintaining components that are reused throughout the entire enterprise. The Standard Development Group would work on new and existing projects that incorporate the use of various components to accomplish various business tasks. In my opinion the incorporation of SCA in to any IT department will initially slow down the number of new features developed due to the time needed to create the new and loosely-coupled components. However once a company becomes more mature in its SCA process then the number of program features developed will greatly increase. I feel this is due to the fact that the loosely-coupled components needed in order to add the new features will already be built and ready to incorporate into any new development feature request. References: BEA Systems, Cape Clear Software, IBM, Interface21, IONA Technologies PLC, Oracle, Primeton Technologies Ltd, Progress Software, Red Hat Inc., Rogue Wave Software, SAP AG, Siebel Systems, Software AG, Sun Microsystems, Sybase, TIBCO Software Inc. (2006). Service Component Architecture. Retrieved 11 27, 2011, from DeveloperWorks: http://www.ibm.com/developerworks/library/specification/ws-sca/ High, R. (2007). The SOA Component Model. Retrieved 11 26, 2011, from InfoQ: http://www.infoq.com/presentations/rob-high-sca-sdo-soa-programming-model

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  • 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…

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  • null values vs "empty" singleton for optional fields

    - by Uko
    First of all I'm developing a parser for an XML-based format for 3D graphics called XGL. But this question can be applied to any situation when you have fields in your class that are optional i.e. the value of this field can be missing. As I was taking a Scala course on coursera there was an interesting pattern when you create an abstract class with all the methods you need and then create a normal fully functional subclass and an "empty" singleton subclass that always returns false for isEmpty method and throws exceptions for the other ones. So my question is: is it better to just assign null if the optional field's value is missing or make a hierarchy described above and assign it an empty singleton implementation?

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  • Twitter Storm VS. Google's MapReduce

    - by Edward J. Yoon
    IMO, the era of Information Retrieval is dead with the advent of SNS. And the question type is changed from "How many backlinks your site has?" to "How many people have clicked URL you've shared on SNS?". So many people who newbie in Big Data Analytics often asks me "How can I analyze stream data time-series pattern mining methods using Map/Reduce?", "How can I mining the valuable insights using Map/Reduce?", "blah~ blah~ using Map/Reduce?". The answer is No Map/Reduce.

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  • How to play many sounds at once in OpenAL

    - by Krom
    Hello, I'm developing an RTS game and I would like to add sounds to it. My choice has landed on OpenAL. I have plenty of units which from time to time make sounds: fSound.Play(sfx_shoot, location). Sounds often repeat, e.g. when squad of archers shoots arrows, but they are not synced with each other. My questions are: What is the common design pattern to play multiple sounds in OpenAL, when some of them are duplicate? What are the hardware limitations on sounds count and tricks to overcome them?

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  • Java web UI framework like ASP.NET MVC?

    - by Ethel Evans
    I'm doing some web apps for personal projects that might be shared out with my friends. I'm trying to use skills that will help me at work, but don't have $$ to spend on Visual Studio right now and don't want to try to cobble something together with Express Editions. Since I've been sort of wanting to bring my Java skills up to date and the main skills I want to work on are design and architecture skills, this isn't a big deal - except that I have no idea how to track down the right UI framework. I know I want something based on MVC, to get more practice with frameworks for that design pattern (we're using ASP .NET MVC2 at work). The UIs that I'll be making will be pretty simple - data entry, buttons, text, images. They will need AJAX. Any thoughts about which frameworks to look at? I'll be watching the comments, if anyone wants additional clarification on what I'm looking for.

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  • Jersey 1.8 is released

    - by Jakub Podlesak
    On the last Friday, we have released the 1.8 version of Jersey, the open source, production quality, reference implementation of JAX-RS. The JAX-RS 1.1 specification is available at the JCP web site and also available in non-normative HTML here. For an overview of JAX-RS features read the Jersey user guide. To get started with Jersey read the getting started section of that guide. To understand more about what Jersey depends on read the dependencies section of that guide. See change log here. This, 1.8, version of Jersey is going to be integrated into GlassFish 3.1.1 and contains bug fixes mainly. The most important fix from this perspective is included in the JAX-RS/EJB integration layer. It is now possible to implement JAX-RS resources as EJB Session beans, which implement local and/or remote interfaces. This functionality was broken in previous releases. Another great addition should come into the client space, where Pavel has already done some preparation in the client API (including some breaking changes there) for the non-blocking asynchronous client feature. The implementation is already part of the experimental Jersey space and should be included as part of the stable Jersey bits in some of the coming releases. For feedback send email to: [email protected] (archived here) or log bugs/features here.

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  • problems with installation of ubuntu 12.04 (64 and 32 bits)

    - by user76104
    I am a latinoamerican so.. sorry for my english I am trying to install ubuntu on my new pc but I have serious problems. When I put the installation cd and it runs, everything goes fine until that "window" when the user have to decide if want to try ubuntu or install it on the machine.. well that "window" apears in blank, and I see that my mouse and my keyboard turn really slowly and I can't do anything I have to shut it down by pressing power botton. The specification of my pc are this Gigabyte ex58 ud7 i7 950 wester digital caviar black 6gb memory corsair evga gtx580 Please i really neeed to install ubuntu or another linux distrubution, i am usign de sismic unix program on my laptop and well. it burns when i program a script! help! please :) what can i do..? what i have to download? i am not a pro in linux so please :( be pattient with me when it starts to load the achieve ubuntu environment to enter a menu with a graphical environment but I managed to get something sturdy and gave him to try ubuntu, started to load but freezes on the sign of ubuntu with red spots and only shows me the pointer not more ..... any other option? ps: had previously tried to install the alternate version of ubuntu not having success: S

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  • What options are there for integrating with payment gateways?

    - by Rowland Shaw
    It seems that there are only two types of payment gateway service out there at the moment; Either that the entire cart logic is handled offsite (with something like Paypal's Standard option) or the other option being that you need to go through the certification for handling credit card numbers and doing pretty much everything yourself. Ideally, for the project I'm working on, I'm after a bit of middle ground such that I can handle the cart on-site, and only pass over to a payment gateway (with an order amount, billing & delivery details, and order ref) for them to handle the card details, before passing back. I'm sure that I've used e-commerce sites using this pattern before, but I cannot find any payment providers out there that offer this sort of option, so are there any? The only over requirement we have at present is that it must accept orders in Sterling.

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