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  • How to deal with a CEO making all technical decision but with little technical knowledge ?

    - by anonymous
    Hi, Question posted anonymously for obvious reasons. I am working in a company with a dev group of 5-6 developers, and I am in a situation which I have a hard time dealing with. Every technical choice (language, framework, database, database scheme, configuration scheme, etc...) is decided by the CEO, often without much rationale. It is very hard to modify those choices, and his main argument consists in "I don't like this", even though we propose several alternative with detailed pros/cons. He will also decide to rewrite from scratch our core product without giving a reason why, and he never participates to dev meetings because he considers it makes things slower... I am already looking at alternative job opportunities, but I was wondering if there anything we (the developers) could do to improve the situation. Two examples which shocked me: he will ask us to implement something akin to configuration management, but he reject any existing framework because they are not written in the language he likes (even though the implementation language is irrelevant). He also expects us to be able to write those systems in a couple of days, "because it is very simple". he keeps rewriting from scratch on his own our core product because the current codebase is too bad (codebase whose design was his). We are at our third rewrite in one year, each rewrite worse than the previous one. Things I have tried so far is doing elaborate benchmarks on our product (he keeps complaining that our software is too slow, and justifies rewrites to make it faster), implement solutions with existing products as working proof instead of just making pros/cons charts, etc... But still 90 % of those efforts go to the trashbox (never with any kind of rationale behind he does not like it, again), and often get reprimanded because I don't do exactly as he wants (not realizing that what he wants is impossible).

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  • Windows 8 Developer Camp - Raleigh September 25th

    - by Jim Duffy
    Time is ticking away and the time to act is now! How's that for some motivation? :-)  Microsoft Developer Evangelist Brian Hitney and I want to help you get your app in the store in time for the October 26 Windows 8 launch. Come join us on Tuesday, September 25, at 9:00 AM in the Microsoft RTP offices to learn how simple it can be to construct a world class Windows 8 application. Don't think you can be ready to join the Windows 8 launch? Come anyway. You might be surprised. Don't have any idea what kind of app to build? Come anyway. They're are plenty of places to look for inspiration. Either way you can learn what it takes to create or tune an app for Windows 8 and publish it in the Windows App Store. Learn more about this free event on the registration page. Registration is now open and space is limited. Have a day.

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  • Testing of visualization projects

    - by paxRoman
    We develop small to large visualization projects for different tasks and industries and sometimes while rewriting them a couple of times in the process we hit walls because we discover that we need to add a lot of code to support new requirements. Now we have established a design process that seems to work well (at least we reduced the development time for each new project quite a bit), but we're still left scratching our heads around this question: what exactly should we test when testing visualizations? If everything that we want to explore is on the screen (bounded visualizations)? If the data is ok - if data is valid (that's one of the nice things about visualizations you can spot errors in your datasets)? Usability? User interaction? Code quality? I can tell you for sure that a simple check of the code quality is certainly not enough! Is there a classic paper / book about how to test visualizations? Also do you happen to know about classic design patterns for visualizations (except the obvious ones like Pub-Sub)?

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  • Weekend Project: Build a Fireball Launcher

    - by Jason Fitzpatrick
    What’s more fun than playing with fire? Shooting it from your hands. Put on your robe and wizard hat, make a stop at the hardware store, and spend the weekend trying to convince your friends you’ve acquired supernatural powers. Over at MAKE Magazine, Joel Johnson explains the impetus for his project: A stalwart of close-quarter magicians for years, the electronic flash gun is a simple device: a battery-powered, hand-held ignitor that uses a “glo-plug” to light a bit of flash paper and cotton, shooting a fireball a few feet into the air. You can buy one from most magic shops for around $50, but if you build one on your own, you’ll not only save a few bucks, you’ll also learn how easy it is to add fire effects to almost any electronics project. (And what gadget couldn’t stand a little more spurting flame?) The parts list is minimal but the end effect is pretty fantastic. Hit up the link below for the full build guide, plenty of warnings, and a weekend project that’s sure to impress. How to Own Your Own Website (Even If You Can’t Build One) Pt 3 How to Sync Your Media Across Your Entire House with XBMC How to Own Your Own Website (Even If You Can’t Build One) Pt 2

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  • What determines which Javascript functions are blocking vs non-blocking?

    - by Sean
    I have been doing web-based Javascript (vanilla JS, jQuery, Backbone, etc.) for a few years now, and recently I've been doing some work with Node.js. It took me a while to get the hang of "non-blocking" programming, but I've now gotten used to using callbacks for IO operations and whatnot. I understand that Javascript is single-threaded by nature. I understand the concept of the Node "event queue". What I DON'T understand is what determines whether an individual javascript operation is "blocking" vs. "non-blocking". How do I know which operations I can depend on to produce an output synchronously for me to use in later code, and which ones I'll need to pass callbacks to so I can process the output after the initial operation has completed? Is there a list of Javascript functions somewhere that are asynchronous/non-blocking, and a list of ones that are synchronous/blocking? What is preventing my Javascript app from being one giant race condition? I know that operations that take a long time, like IO operations in Node and AJAX operations on the web, require them to be asynchronous and therefore use callbacks - but who is determining what qualifies as "a long time"? Is there some sort of trigger within these operations that removes them from the normal "event queue"? If not, what makes them different from simple operations like assigning values to variables or looping through arrays, which it seems we can depend on to finish in a synchronous manner? Perhaps I'm not even thinking of this correctly - hoping someone can set me straight. Thanks!

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  • What's a way to implement a flexible buff/debuff system?

    - by gkimsey
    Overview: Lots of games which RPG-like statistics allow for character "buffs", ranging from simple "Deal 25% extra damage" to more complicated things like "Deal 15 damage back to attackers when hit." The specifics of each type of buff aren't really relevant. I'm looking for a (presumably object-oriented) way to handle arbitrary buffs. Details: In my particular case, I have multiple characters in a turn-based battle environment, so I envisioned buffs being tied to events like "OnTurnStart", "OnReceiveDamage", etc. Perhaps each buff is a subclass of a main Buff abstract class, where only the relevant events are overloaded. Then each character could have a vector of buffs currently applied. Does this solution make sense? I can certainly see dozens of event types being necessary, it feels like making a new subclass for each buff is overkill, and it doesn't seem to allow for any buff "interactions". That is, if I wanted to implement a cap on damage boosts so that even if you had 10 different buffs which all give 25% extra damage, you only do 100% extra instead of 250% extra. And there's more complicated situations that ideally I could control. I'm sure everyone can come up with examples of how more sophisticated buffs can potentially interact with each other in a way that as a game developer I may not want. As a relatively inexperienced C++ programmer (I generally have used C in embedded systems), I feel like my solution is simplistic and probably doesn't take full advantage of the object-oriented language. Thoughts? Has anyone here designed a fairly robust buff system before?

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  • andEngine dynamic sprites

    - by Blucreation
    Ive just started with andEngine the past week and i only started learning java/android 3 weeks. I can use a for loop to add multiple sprites to the screen but when i try to check collisions on them it only does it to one and not the rest. I want to be able to add a specific number for sprites made from the same texture to the scene, add collision detection to them and also make them slide across the screen (im making a game where you avoid the obstacles). My simple code: private void createobstacle(float pX, float pY) { obstacle = new AnimatedSprite(pX, pY, this.mObjTextureRegion.deepCopy(), getVertexBufferObjectManager()); obstacle.setScale(MathUtils.random(0.5f, 3f)); scene.attachChild(obstacle); } private void createobstacle(int num) { for(int i=0; i<=num; i++ ) { final float xPos = MathUtils.random(30.0f, (CAMERA_WIDTH - 30.0f)); final float yPos = MathUtils.random(30.0f, (CAMERA_HEIGHT - 30.0f)); createobstacle(xPos, yPos); } } Ive read about arrays but i cannot find any tutorials about anything im stuck with. Any help would be great!

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  • Balancing dependency injection with public API design

    - by kolektiv
    I've been contemplating how to balance testable design using dependency injection with providing simple fixed public API. My dilemma is: people would want to do something like var server = new Server(){ ... } and not have to worry about creating the many dependencies and graph of dependencies that a Server(,,,,,,) may have. While developing, I don't worry too much, as I use an IoC/DI framework to handle all that (I'm not using the lifecycle management aspects of any container, which would complicate things further). Now, the dependencies are unlikely to be re-implemented. Componentisation in this case is almost purely for testability (and decent design!) rather than creating seams for extension, etc. People will 99.999% of the time wish to use a default configuration. So. I could hardcode the dependencies. Don't want to do that, we lose our testing! I could provide a default constructor with hard-coded dependencies and one which takes dependencies. That's... messy, and likely to be confusing, but viable. I could make the dependency receiving constructor internal and make my unit tests a friend assembly (assuming C#), which tidies the public API but leaves a nasty hidden trap lurking for maintenance. Having two constructors which are implicitly connected rather than explicitly would be bad design in general in my book. At the moment that's about the least evil I can think of. Opinions? Wisdom?

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  • Network: Incoming connections work, outgoing fails

    - by anirvan
    i recently set up my own server at home to run Ubuntu 12.04 server ed. on booting up, i noticed that a message related to networking comes up, and the booting process pauses. the message read something like - waiting for network configuration and after a while - waiting another 60 seconds... on booting up, I realised that any command which requires a network connection was not working - ping, apt-get install, etc. on firing the ifup eth0 command, I get the error RTNETLINK answers: File exists. Failed to bring up eth0. I also realised, while searching the web for this problem, that this is probably one of the most common networking related issues - however, most of the questions are around setting up multiple IPs for the same machine. ifdown eth0 also fails, stating that eth0 is not configured. my /etc/network/interfaces file has a simple configuration for a static IP: auto lo iface lo inet loopback auto eth0 iface eth0 inet static address xx.xx.xx.xx netmask xx.xx.xx.xx broadcast xx.xx.xx.xx gateway xx.xx.xx.xx dns-nameservers xx.xx.xx.xx The strangest part of this problem is that, while I can't connect to anything outside, I can ping to this particular server using the static IP configured in the interface file, and, i can even SSH into it! I'm really at ends here with this problem, and any guidance is much appreciated. Thanks!

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  • Interpolation between two 3D points?

    - by meds
    I'm working with some splines which define a path a character follows (you can see a gameplay video here to get a better understanding of what's going on: http://www.youtube.com/watch?v=BndobjOiZ6g). Basically the characters 'forward' look direction is set to the 'forward' direction of the spline and when players tilt their phone left and right the character is strafed along its 'right' coordinate. The issue with this is (rather obviously) in performance, interpolating over a spline to find the nearest position and tangent relative to the player is an incredibly costly operation. To get by this I cache a finite number of positions in what I call 'SplineDetails', the class is as follows: public class SplineDetails { public SplineDetails() { Forward = Vector3.forward; Position = Vector3.one * float.MaxValue; Alpha = -1; } public float Alpha; // [0,1] measured along length of spline where 0 is the initial point and 1 is the end point of the spline public Vector3 Position; // the point of the spline at this alpha public Vector3 Forward; // the forward tangent of the spline at this alpha } I populate this with say 30 coordinates and I can give a rough estimate of a coordinate and 'forward' based on a position past in. It's not as accurate but it's much faster. But now I'd like to make the system work better by estimating positions and 'forward' directions by interpolating between two of the cached points though I'm stuck trying to figure out some logic. My first problem is, how can I determine between which two points the object is? Given each point can be placed at different intervals along the spline it could mean that two points in front or behind the object can be closer to the object. The other problem is to figure out the proportion between the two paths it's between, i.e. if there is a point a at coordinate (0,0,0) and point b at coordinate (1,0,0) if the object is at position (0.5,0,0) then the result it should give is '0.5' (as it is equal distance away from point a and point b). That's a simple example, but what if the object is at coordinate (0.5,3,0) for example?

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  • Strategy for hosting 700+ domains names, each with a static HTML site

    - by jonschlinkert
    I have a portfolio of more than 700 domain names, and ideally I'd like to put up a single-page HTML/CSS/JavaScript webpage for each domain. Is there a system/strategy/workflow that will allow me to: Automate the deployment of new websites, quickly and easily without having to manually initiate each new website in an admin panel. For instance, I've seen dropbox-based solutions that claim to make it simple to setup new websites on your dropbox account, but you still have to set each one up in an admin interface first. It would be so much easier to have a folder naming convention that allowed the user to easily clone/copy/duplicate sites inside their Dropbox App folder (https://www.dropbox.com/developers/blog/23) to create new ones. Sounds interesting, however... It's easy to manage CNAMEs on the registrar-side, but is there a way to quickly associate CNAMEs with new websites (on the hosting side), maybe using the method offered by gh-pages-style (https://help.github.com/articles/setting-up-a-custom-domain-with-pages)? With GitHub's gh-pages, all you have to do is drop a file called CNAME into your repo, with the domain name you want associated with the repo inside the file. gh-pages isn't a good solution for what I'm doing though unfortunately. I'm also a front-end developer, specializing in rapid web development and "front-end build systems", so I building and maintaining static assets for hundreds of sites is no problem. It's the hosting-side that I really struggle with. Any suggestions?

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  • The Enterprise Side of JavaFX: Part Two

    - by Janice J. Heiss
    A new article, part of a three-part series, now up on the front page of otn/java, by Java Champion Adam Bien, titled “The Enterprise Side of JavaFX,” shows developers how to implement the LightView UI dashboard with JavaFX 2. Bien explains that “the RESTful back end of the LightView application comes with a rudimentary HTML page that is used to start/stop the monitoring service, set the snapshot interval, and activate/deactivate the GlassFish monitoring capabilities.”He explains that “the configuration view implemented in the org.lightview.view.Browser component is needed only to start or stop the monitoring process or set the monitoring interval.”Bien concludes his article with a general summary of the principles applied:“JavaFX encourages encapsulation without forcing you to build models for each visual component. With the availability of bindable properties, the boundary between the view and the model can be reduced to an expressive set of bindable properties. Wrapping JavaFX components with ordinary Java classes further reduces the complexity. Instead of dealing with low-level JavaFX mechanics all the time, you can build simple components and break down the complexity of the presentation logic into understandable pieces. CSS skinning further helps with the separation of the code that is needed for the implementation of the presentation logic and the visual appearance of the application on the screen. You can adjust significant portions of an application's look and feel directly in CSS files without touching the actual source code.”Check out the article here.

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  • Taming Hopping Windows

    - by Roman Schindlauer
    At first glance, hopping windows seem fairly innocuous and obvious. They organize events into windows with a simple periodic definition: the windows have some duration d (e.g. a window covers 5 second time intervals), an interval or period p (e.g. a new window starts every 2 seconds) and an alignment a (e.g. one of those windows starts at 12:00 PM on March 15, 2012 UTC). var wins = xs     .HoppingWindow(TimeSpan.FromSeconds(5),                    TimeSpan.FromSeconds(2),                    new DateTime(2012, 3, 15, 12, 0, 0, DateTimeKind.Utc)); Logically, there is a window with start time a + np and end time a + np + d for every integer n. That’s a lot of windows. So why doesn’t the following query (always) blow up? var query = wins.Select(win => win.Count()); A few users have asked why StreamInsight doesn’t produce output for empty windows. Primarily it’s because there is an infinite number of empty windows! (Actually, StreamInsight uses DateTimeOffset.MaxValue to approximate “the end of time” and DateTimeOffset.MinValue to approximate “the beginning of time”, so the number of windows is lower in practice.) That was the good news. Now the bad news. Events also have duration. Consider the following simple input: var xs = this.Application                 .DefineEnumerable(() => new[]                     { EdgeEvent.CreateStart(DateTimeOffset.UtcNow, 0) })                 .ToStreamable(AdvanceTimeSettings.IncreasingStartTime); Because the event has no explicit end edge, it lasts until the end of time. So there are lots of non-empty windows if we apply a hopping window to that single event! For this reason, we need to be careful with hopping window queries in StreamInsight. Or we can switch to a custom implementation of hopping windows that doesn’t suffer from this shortcoming. The alternate window implementation produces output only when the input changes. We start by breaking up the timeline into non-overlapping intervals assigned to each window. In figure 1, six hopping windows (“Windows”) are assigned to six intervals (“Assignments”) in the timeline. Next we take input events (“Events”) and alter their lifetimes (“Altered Events”) so that they cover the intervals of the windows they intersect. In figure 1, you can see that the first event e1 intersects windows w1 and w2 so it is adjusted to cover assignments a1 and a2. Finally, we can use snapshot windows (“Snapshots”) to produce output for the hopping windows. Notice however that instead of having six windows generating output, we have only four. The first and second snapshots correspond to the first and second hopping windows. The remaining snapshots however cover two hopping windows each! While in this example we saved only two events, the savings can be more significant when the ratio of event duration to window duration is higher. Figure 1: Timeline The implementation of this strategy is straightforward. We need to set the start times of events to the start time of the interval assigned to the earliest window including the start time. Similarly, we need to modify the end times of events to the end time of the interval assigned to the latest window including the end time. The following snap-to-boundary function that rounds a timestamp value t down to the nearest value t' <= t such that t' is a + np for some integer n will be useful. For convenience, we will represent both DateTime and TimeSpan values using long ticks: static long SnapToBoundary(long t, long a, long p) {     return t - ((t - a) % p) - (t > a ? 0L : p); } How do we find the earliest window including the start time for an event? It’s the window following the last window that does not include the start time assuming that there are no gaps in the windows (i.e. duration < interval), and limitation of this solution. To find the end time of that antecedent window, we need to know the alignment of window ends: long e = a + (d % p); Using the window end alignment, we are finally ready to describe the start time selector: static long AdjustStartTime(long t, long e, long p) {     return SnapToBoundary(t, e, p) + p; } To find the latest window including the end time for an event, we look for the last window start time (non-inclusive): public static long AdjustEndTime(long t, long a, long d, long p) {     return SnapToBoundary(t - 1, a, p) + p + d; } Bringing it together, we can define the translation from events to ‘altered events’ as in Figure 1: public static IQStreamable<T> SnapToWindowIntervals<T>(IQStreamable<T> source, TimeSpan duration, TimeSpan interval, DateTime alignment) {     if (source == null) throw new ArgumentNullException("source");     // reason about DateTime and TimeSpan in ticks     long d = Math.Min(DateTime.MaxValue.Ticks, duration.Ticks);     long p = Math.Min(DateTime.MaxValue.Ticks, Math.Abs(interval.Ticks));     // set alignment to earliest possible window     var a = alignment.ToUniversalTime().Ticks % p;     // verify constraints of this solution     if (d <= 0L) { throw new ArgumentOutOfRangeException("duration"); }     if (p == 0L || p > d) { throw new ArgumentOutOfRangeException("interval"); }     // find the alignment of window ends     long e = a + (d % p);     return source.AlterEventLifetime(         evt => ToDateTime(AdjustStartTime(evt.StartTime.ToUniversalTime().Ticks, e, p)),         evt => ToDateTime(AdjustEndTime(evt.EndTime.ToUniversalTime().Ticks, a, d, p)) -             ToDateTime(AdjustStartTime(evt.StartTime.ToUniversalTime().Ticks, e, p))); } public static DateTime ToDateTime(long ticks) {     // just snap to min or max value rather than under/overflowing     return ticks < DateTime.MinValue.Ticks         ? new DateTime(DateTime.MinValue.Ticks, DateTimeKind.Utc)         : ticks > DateTime.MaxValue.Ticks         ? new DateTime(DateTime.MaxValue.Ticks, DateTimeKind.Utc)         : new DateTime(ticks, DateTimeKind.Utc); } Finally, we can describe our custom hopping window operator: public static IQWindowedStreamable<T> HoppingWindow2<T>(     IQStreamable<T> source,     TimeSpan duration,     TimeSpan interval,     DateTime alignment) {     if (source == null) { throw new ArgumentNullException("source"); }     return SnapToWindowIntervals(source, duration, interval, alignment).SnapshotWindow(); } By switching from HoppingWindow to HoppingWindow2 in the following example, the query returns quickly rather than gobbling resources and ultimately failing! public void Main() {     var start = new DateTimeOffset(new DateTime(2012, 6, 28), TimeSpan.Zero);     var duration = TimeSpan.FromSeconds(5);     var interval = TimeSpan.FromSeconds(2);     var alignment = new DateTime(2012, 3, 15, 12, 0, 0, DateTimeKind.Utc);     var events = this.Application.DefineEnumerable(() => new[]     {         EdgeEvent.CreateStart(start.AddSeconds(0), "e0"),         EdgeEvent.CreateStart(start.AddSeconds(1), "e1"),         EdgeEvent.CreateEnd(start.AddSeconds(1), start.AddSeconds(2), "e1"),         EdgeEvent.CreateStart(start.AddSeconds(3), "e2"),         EdgeEvent.CreateStart(start.AddSeconds(9), "e3"),         EdgeEvent.CreateEnd(start.AddSeconds(3), start.AddSeconds(10), "e2"),         EdgeEvent.CreateEnd(start.AddSeconds(9), start.AddSeconds(10), "e3"),     }).ToStreamable(AdvanceTimeSettings.IncreasingStartTime);     var adjustedEvents = SnapToWindowIntervals(events, duration, interval, alignment);     var query = from win in HoppingWindow2(events, duration, interval, alignment)                 select win.Count();     DisplayResults(adjustedEvents, "Adjusted Events");     DisplayResults(query, "Query"); } As you can see, instead of producing a massive number of windows for the open start edge e0, a single window is emitted from 12:00:15 AM until the end of time: Adjusted Events StartTime EndTime Payload 6/28/2012 12:00:01 AM 12/31/9999 11:59:59 PM e0 6/28/2012 12:00:03 AM 6/28/2012 12:00:07 AM e1 6/28/2012 12:00:05 AM 6/28/2012 12:00:15 AM e2 6/28/2012 12:00:11 AM 6/28/2012 12:00:15 AM e3 Query StartTime EndTime Payload 6/28/2012 12:00:01 AM 6/28/2012 12:00:03 AM 1 6/28/2012 12:00:03 AM 6/28/2012 12:00:05 AM 2 6/28/2012 12:00:05 AM 6/28/2012 12:00:07 AM 3 6/28/2012 12:00:07 AM 6/28/2012 12:00:11 AM 2 6/28/2012 12:00:11 AM 6/28/2012 12:00:15 AM 3 6/28/2012 12:00:15 AM 12/31/9999 11:59:59 PM 1 Regards, The StreamInsight Team

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  • Dojo and Separate JavaScript File

    - by Bunch
    For a project I needed to use the ArcGIS API for some mapping. To use this you need to use Dojo but in this case all it really comes down to is adding some require lines and a addOnLoad on your web page. At first everything was working great, the maps rendered and the various layers would populate as needed. Once it was working I started moving the various javascript functions into their own files to keep everything nice and neat. Then the problems started, mainly the map would not show up any more. So that was a pretty big problem. Luckily the fix was pretty simple, just move the dojo.addOnLoad line into it’s own script tag. If I had the dojo.addOnLoad in the same script block as the various require lines it would not work as expected. Works: <script type="text/javascript" language="javascript" src="javascript/test.js" />     <script type="text/javascript">       dojo.require("esri.map");       dojo.require("esri.tasks.locator");       dojo.require("esri.tasks.query");       dojo.require("esri.tasks.geometry");  </script>  <script type="text/javascript">      dojo.addOnLoad(init);  </script> Does not work: <script type="text/javascript" language="javascript" src="javascript/test.js" /> <script type="text/javascript">       dojo.require("esri.map");       dojo.require("esri.tasks.locator");       dojo.require("esri.tasks.query");       dojo.require("esri.tasks.geometry");       dojo.addOnLoad(init); </script> Technorati Tags: JavaScript,Dojo

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  • Using Clojure instead of Python for scalability (multi core) reasons, good idea?

    - by Vandell
    After reading http://clojure.org/rationale and other performance comparisons between Clojure and many languages, I started to think that apart from ease of use, I shouldn't be coding in Python anymore, but in Clojure instead. Actually, I began to fill irresponsisble for not learning clojure seeing it's benefits. Does it make sense? Can't I make really efficient use of all cores using a more imperative language like Python, than a lisp dialect or other functional language? It seems that all the benefits of it come from using immutable data, can't I do just that in Python and have all the benefits? I once started to learn some Common Lisp, read and done almost all exercices from a book I borrowod from my university library (I found it to be pretty good, despite it's low popularity on Amazon). But, after a while, I got myself struggling to much to do some simple things. I think there's somethings that are more imperative in their nature, that makes it difficult to model those thins in a functional way, I guess. The thing is, is Python as powerful as Clojure for building applications that takes advantages of this new multi core future? Note that I don't think that using semaphores, lock mechanisms or other similar concurrency mechanism are good alternatives to Clojure 'automatic' parallelization.

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  • TraceTune: Larger Files and History

    - by Bill Graziano
    I updated TraceTune over the weekend.  I increased the trace file upload size to 20MB.  We’ve processed over half a million rows of trace data so far and I’m confident this won’t kill the server. I added average CPU and average disk reads to the screen that lists the SQL statements in a trace file. I only added these two.  I’m pretty sure average writes isn’t that import.  I’m still thinking about average duration.  I’m trying to balance showing you what you need with a clean, simple interface.  Plus I have a way to see the averages that I describe further down. TraceTune now keeps the last 10 files that you’ve uploaded and will give you some basic details about each file. I think the last change I made is the most interesting. For each SQL statement, I show the history of that statement. You’ll see each trace file where this statement was found.  It will list the averages for CPU, reads, writes and duration.  This will quickly show you if you’re improving the performance of that query.  In my screen shot above you can that even though the execution counts are very different the averages are consistent. If you want to see what queries are consuming the most resources on your server give TraceTune a try.

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  • OS8- AK8- The bad news...

    - by Steve Tunstall
    Ok I told you I would give you the bad news of AK8 to go along with all the cool new stuff, so here it is. It's not that bad, really, just things you need to be aware of. First, the 2013.1 code is being called OS8, AK8 and 2013.1 by different people. I mean different people INSIDE Oracle!! It was supposed to be easy, but it never is. So for the rest of this blog entry, I'm calling it AK8. AK8 is not compatible with the 7x10 series. Ever. The 7x10 series is not supported with AK8, and if you try to upgrade one, it will fail at the healthcheck. All 7x20 series, all of them regardless of age, are supported with AK8. Drive trays. Let's talk about drive trays and SAS cards. The older drive trays for the 7x20 series were called the "Riverwalk 2" or "DS2" trays. They were technically the "J4410" series JBODs that Sun used to sell a la carte before we stopped selling JBODs. Don't get me started on that, it still makes me mad. We used these for many years, and you can still buy them right now until December 15th, 2013, when they will no longer be sold. The DS2 tray only came as a 4u, 24 drive shelf. It held 3.5" drives, and you had a choice of 2TB, 3TB, 300GB or 600GB drives. The SAS HBA in the 7x20 series was called a "Thebe" card, with a part # of 7105394. The 7420, for example, came standard with two of these "Thebe" cards for connecting to the disk trays. Two Thebe cards could handle up to 12 trays, so one would add two more cards to go to 24 trays, or have up to six Thebe cards to handle 36 trays. This card was for external SAS only. It did not connect to the internal OS drives or the Readzillas, both of which used the internal SCSI controller of the server. These Riverwalk 2 trays ARE supported with AK8. You can upgrade your older 7420 or 7320, no problem, as-is. The much older Riverwalk 1 trays or J4400 trays are NOT supported by AK8. However, they were only used by the 7x10 series, and we already said that the 7x10 series was not supported. Here's where it gets tricky. Since last January, we have been selling the new style disk trays. We call them the "DE2-24P" and the "DE2-24C" trays. The "C" tray is for capacity drives, which are 3.5" 3TB or 4TB drives. The "P" trays are for performance drives, which are 2.5" 300GB and 900GB drives. These trays are NOT Riverwalk 2 trays, even though the "C" series may kind of look like it. Different manufacturer and different firmware. They are not new. Like I said, we've been selling them with the 7x20 series since last January. They are the only disk trays we will be selling going forward. Of course, AK8 supports them. So what's the problem? The problem is going to be for people who have to mix drive trays. Remember, your older 7x20 series has Thebe SAS2 HBAs. These have 2 SAS ports per card.  The new ZS3-2 and ZS3-4 systems, however, have the new "Thebe2" SAS2 HBAs. These Thebe2 cards have 4 ports per card. This is very cool, as we can now do more SAS channels with less cards. Instead of needing 4 SAS cards to grow to 24 trays like we did with the old Thebe cards, I can now do 24 trays with only 2 Thebe2 cards. This means more IO slots for fun things like Infiniband and 10G. So far, so good, right? These Thebe2 cards work with any disk tray. You can even mix older DS2 trays with the newer DE2 trays in the same system, as long as you have Thebe2 cards. Ah, there's your problem. You don't have Thebe2 cards in your old 7420, do you? Well, I told you the bad news wasn't that bad, right? We can take out your Thebe cards and replace them with Thebe2. You can then plug your older DS2 trays right back in, and also now get newer DE2 trays going forward. However, it's important that the trays are on different SAS channels. You can mix them in the same system, but not on the same channel. Ask your local SC if you need help with the new cable layout. By the way, the new ZS3-2 and ZS3-4 systems also include a new IO card called "Erie" cards. These are for INTERNAL SAS to the OS drives and the Readzillas. So those are now SAS2 instead of SATA like the older models. Yes, the Erie card uses an IO slot, but that's OK, because the Thebe2 cards allow us to use less SAS HBAs to grow the system, right? That's it. Not too much bad news and really not that bad. AK8 does not support the 7x10 series, and you may need new Thebe2 cards in your older systems if you want to add on newer DE2 trays. I think we can all agree that there are worse things out there. Like our Congress.   Next up.... More good news and cool AK8 tricks. Such as virtual NICS. 

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  • GPU based procedual terrain borders?

    - by OnePie
    I'm working on a game that preferibly should feature a combination of designed and procedually generated terrain where the designer specifies in somewhat detailed terms what type of terrain a given area will have (grasslands, forest etc...) and then a precedual algorithm takes care of the rest. I'm not talking about minecraft style biomoes, but rather the game map for a strategy game. Each 'area' will not take up that much of the screen, and thus be more akin to a tile whose texture is procedually generated. While procedually generating terrain textures on the GPU are not that difficult, the hard part is making the borders between them look good. Currently, the 'tiles' are large enough to be visible (due to memory constraints mainly, we are talking planetary sized textures for a game taking place in space and on a continental ground view with seamless transitions between them) and creating good borders between them with an algorithm that is fast enough to be useful has proven difficult. Sampling the n-surrounding pixels and using the combiened result did not yield very good borders and was fairly slow on the GPU to boot (ca 12ms for me, that is without any lighning or shading and with very simple terrain texture shaders). So are there any practical known methods to solve this problem?

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  • What should I "forget" when going to Javascript?

    - by ElGringoGrande
    I went from C=64 Basic and assembler to FORTRAN and C to C++ and Java. Professionally I started in Visual Basic for applications then to Visual Basic 4, 5, 6. After that VB.NET AND C# with some Java here and there. I have played with Ruby and Python and found both fun. During each step I never felt like I had to forget what I had learned before. I always felt like I was just learning better and/or slightly different ways of doing things but the difference was not major. The difference was like the difference between American, Australian and British English. (Maybe assembler was Latin and FORTRAN was Spanish.) But now I am using JavaScript to do real, actual work. (Before used it as a "Scripting" language pure a simple.) And I just feel like I have to forget some things to become proficient in it. It feels like some old Egyptian language. What should I forget? Is it just that code organization is different (no real classes so no one class one file)? Or is it something more basic?

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  • Experienced programmer, beginner at web design, tools for effective maintainable web design? [closed]

    - by Clinton
    I do quite a bit of programming in my work, which I'm comfortable with, but recently I've being trying to do some web-design for non-work related reasons. I've got a Drupal site up and running, and added some content. But they all look fairly basic. Header with some content. It doesn't look particularly polished. Anyway, as an example, what I wanted to do was make some "bubbles", each with some text in them. From a programmers point of view, say: bubble(question_text, answer_text) might expand to a box with some border, with "Question: " + question_text then "Answer: " + answer_text. Of course I'd have lots of these bubbles, but I'd like to change their look and feel in one place, so simple HTML would be a maintainable nightmare. I also want to lay them out on the screen in some fashion. I was thinking a mixture of javascript and CSS, or possibly use PHP which Drupal uses. On the other hand, I fear I might be taking a 1990s approach to this, and that there's actually tools available now that make this process a lot easier. I'm just wondering what the best approach to this sort of task is? Should I be using offline web design software and copying the code to Drupal, and if so, any recommendations? I'm sorry if my question is a bit vague, because I'm not really sure what question I should be asking. I'd appreciate if you answer and comment, and I'll try my best to be more specific as I understand more.

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  • Oracle Tutor - Is Anyone Reading Your Documentation?

    - by mary.keane
    If you are responsible for documenting your business practices, wouldn't it be nice to know if anyone is using the documentation? If the employees find it useful? You might want to consider surveying the users of the documentation on a regular basis. There are a number of free survey tools online (search for "free survey tools"), and you can have a survey ready in a matter of minutes. It's as simple as gathering a list of questions and a list of email addresses. For the questions, here are some suggestions. How often do you access the policy and procedure site? How useful is the site? How easy is it to navigate the site? How often are your questions answered on the site? What suggestions do you have to make the site more useful? You may want to consider just asking a few questions each month so that employees can complete the survey in less than 5 minutes (you'll get more responses). Make sure you have several comment boxes in the survey so that the employees can give suggestions. As the users of your documentation, the employees may have some terrific ideas that will enhance the usability of your policy and procedure site. It would be great to hear your suggestions for how to survey the users of your documentation. Mary R. Keane Senior Development Manager, Oracle BPM and Tutor

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  • Understanding IDAT chunk of PNG file format

    - by DRapp
    From the sample image below, I have a border in yellow just for display purposes only. The actual .png file is a simple black/white image 3 pixels by 3 pixels. I was originally thinking to try as a 2x2, but that would not help trying to interpret low/hi vs hi/low drawing stream. At least this way, I would have two black, one white from the top, or one white, two black from the bottom.. So I read the chunks of data, get to the IDAT chunk, decode that (zlib) and come up with 12 bytes as follows 00 20 00 40 00 80 So, my question, how does the above get broken down into the 3x3 black and white sample... Also, it is saved in palette format and properly recognizes the bit depth of 1 and color palette of 2... color pallet[0] is RGBA all zeros. Palette1 has RGBA of 255, 255, 255, 0 I'll eventually get into the multiple other depth formats later, just wanted to start with what would expect to be the easiest. Part II. Any guidance on handling the other depth formats would help if anything special to be considered especially regarding alpha channel (which I am already looking for in the palette) that might trip me up.

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  • Writing Java in Java

    - by Skeith
    I have been using Java for several months at work now and am becoming mildly competent in it. The problem I think I am having is that I program C++ in Java . By that I mean I have always used C++ and am treating Java as a simple syntax change instead of appreciate if for its own language. For instance a static variable in C++ is the same as a normal variable in Java as Java is all classes so they maintain there values between function calls. Little things like this are tripping me up constantly as I am self taught. What I want is to invest the time to become a good java programmer not just a C++ programmer that can write in Java. The problem is I do not know how to do this. I have tried reading the Java doc pages but I find them very clinical and hard to understand. So what I am looking for is recommendations on how I can learn to think in Java. Books that teach Java concepts not Java syntax, online tutorials that I can work through that give it a context, established Java traditions/best practices and any other thing that you could recommend.

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  • tdd is about design not verification what does it concretely mean?

    - by sigo
    I've been wondering about this. What do we exactly mean by design and verification. Should I just apply tdd to make sure my code is SOLID and not check is correct external behaviour ? Should I use Bdd for the correct behaviour part ? Where I get confused also is regarding TDD code katas, to me they looked like more about verification than design... shouldn't they be called bdd katas instead of tdd katas? I reckon that for example uncle bob bowling kata leads in the end to a simple and nice internal design but I felt that most of the process was more around vérification than design. Design seemed to be a side effect of testing incrementally the external behaviour. I didnt feel so much that we were focusing most of our efforts on design but more on vérification. While normally we are told the contrary, that in TDD, verification is a side effect, design is the main purpose. So my question is what should i focus exactly on when i do tdd: SOLID, external Api usability, what else...? And how can I do that without being focused on verification ? What do you guys focus your energy on when you are practicing TDD ?

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  • VNIC - New feature of AK8 - Working with VNICs

    - by Steve Tunstall
    One of the important new features of the AK8 code is the ability to use multiple IP addresses on the same physical network port. This feature is called VNICs, or Virtual NICs. This allows us to no longer "burn" a whole port in a cluster when one cluster peer owns a network port. Traditionally, we have had to leave Net0 empty on controller 2, because it was used for managing controller 1. Vise-versa for Net1 on Controller 1. Then, if you have data going over 10GigE ports, you probably only had half of your ports running at any given time, and the partner 10GigE port on the other controller just sat there, doing nothing, unless the first controller went down. What a waste. Those days are over.  I want to thank and give a big shout-out to our good partner, OnX Enterprise Solutions, for allowing me to come into their lab and play around with their 7320 to do this demo. They let me make a big mess of their lab for the day as I played around with VNICs. If you're looking for a partner who knows Oracle well and can also piece together a solution from multiple vendors to get you what you need, OnX is a good choice. If you would like to talk to your local OnX rep, you can contact Scott Gill at [email protected] and he can point you in the right direction for your area.  Here we go: Here is what your Datalinks window looks like BEFORE you upgrade to AK8. Here's what the same screen looks like after you upgrade. See the new box? So here is my current network setup. I have my 4 physical interfaces setup each with an IP address. If I ping them, no problems.  So I can ping 180, 181, 251, and 252. However, if I try to ping 240, it does not work, as the 240 address is not being used by any of these interfaces, right?Let's change that. Here, I'm going to make a new Datalink by clicking the Datalink "Plus sign" button. I will check the VNIC box and tell it to use igb2, even though another interface is already using it. Now, I will create a new Interface, and choose "v_dl2" for it's datalink. My new network screen looks like this. A few things to take note of here. First, when I click the "igb2" device, it only highlights dl2 and int2. It does not highlight v_dl2 or v_int2.I think it should, but OK, it looks like VNICs don't highlight when you click the device. Second, note how the underscore character in v_dl2 and v_int2 do not seem to show on this screen. You can see it plainly if you go in and edit them, but from here it looks like a space instead of an underscore. Just a cosmetic bug, but something to be aware of. Now, if I click the VNIC datalink "v_dl2", on the other hand, it DOES highlight the device it belongs to, as it should. Seen here: Note that it did not, however, highlight int2 with it, even though int2 is connected to igb2. That's because we clicked v_dl2, which int2 has nothing to do with. So I'm OK with that. So let's try pinging 240 now. Of course, it works great.  So I now make another VNIC, and call it v_dl3 using igb3, and v_int3 with an address of 241. I then setup three shares, using ports 251, 240, and 241.Remember that IP 251 and 240 both are using the same physical port of igb2, and IP 241 is using port igb3. Next, I copy a folder full of stuff over to all three shares at the same time. I have analytics going so I can see the traffic. My top chart is showing the logical interfaces, and the bottom chart is showing the physical ports.Sure enough, look at the igb2 and vnic1 interfaces. They equal the traffic going over the igb2 physical port on the second chart. VNIC2, on the other hand, gets igb3 all to itself. This would work the same way with 10Gig or Infiniband ports. You can now have multiple IP addresses and even completely different subnets sharing the same physical ports. You may need to make route table entries for that. This allows us to use all of the ports you paid for with no more waste.  Very, very cool.  One small "bug" I found when doing this. It's really not a bug, it was designed to do this when VNICs were not around. But now that we have NVIC capability, they should probably change this. I've alerted the engineering team about this and they're looking into it, so perhaps it will be fixed in a later code. Here it is. Remember when we made the new VNIC datalink, I specifically said to click on the "Plus Sign" button to create it? I don't always do that. I really like to use the drag-and-drop method to create my datalinks in the network screen.HOWEVER, if you were to do that for building a VNIC, it will mess you up a little. Watch this. Here, I'm dragging igb3 over to make a new datalink. igb3 is already being used by dl3, but I'm going to make this a VNIC, so who cares, right? Well, the ZFSSA does not KNOW you are going to make it a VNIC, now does it? So... it works as designed and REMOVES the igb3 device from the current dl3 datalink in the background. See how it's now missing? At the same time, the dl3 datalink choice is missing from my list of possible VNICs for me to choose from!!!! Hey!!! I wanted to pick dl3. Why isn't it on the list??? Well, it can't be on this list because dl3 no longer has a device associated with it. Bummer for you. When you click cancel, the device is still missing from dl3. The fix is easy. Just edit dl3 by clicking the pencil button, do absolutely nothing, and click "Apply". The device will magically come back. Now, make the VNIC datalink by clicking the "Plus Sign" button. Sure enough, once you check the VNIC box, dl3 is a valid choice. No problem.  That's it for now. Have fun with VNICs.

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