Search Results

Search found 42090 results on 1684 pages for 'mean square method'.

Page 672/1684 | < Previous Page | 668 669 670 671 672 673 674 675 676 677 678 679  | Next Page >

  • Bad Performance With Games Under Wine in Ubuntu 12.04

    - by Pandem
    I'm somewhat new to Linux. I've dabbled with it before but never more than just experimentation in a VM or dual boot where I almost always reverted back to Windows soon after (more due to a lack of commitment than a dislike for the OS). Anyway my problem is that in the two games (Guild Wars and Team Fortress 2) I've tried so far I get fairly bad performance. Despite both games having a "Platinum" rating I've still been forced to run both in DirectX 8, otherwise they either crash, have texture defects or the UI is missing. By "bad performance" I mean sub-30 FPS where there are some players and regular large framerate drops with video settings on low. Currently in my mind I believe the performance issues are just a problem with the drivers because my graphics card is a AMD 7850 which is virtually brand new and probably not properly supported yet but I'm unsure and would appreciate advice or tips to improve things. I have Ubuntu 12.04 installed and I am usually logged in a Gnome Classic session. I have installed AMD's proprietary drivers (Catalyst version 12.4) and have Wine 1.4 installed. I have used Winetricks to install DX9/DX10 dlls and other things.

    Read the article

  • What language available on commodity web hosts would suit a C# developer? [closed]

    - by billpg
    Recognising its ubiquity on commodity web hosting services, I tried developing in PHP a few years ago. I really didn't like it, later deciding that life was too short for PHP. (In brief, having to put $ on variable names; mis-spelt variable names become new variables; converting non-numeric strings to integers without complaint; the need for an "and this time I mean it" comparison operator.) In my ideal world, commodity web hosts would all support C#/ASP.NET, my preferred web-development language and framework, but this is not my ideal world. Even Mono has barely made a dent on Linux based hosts. However, last time I moaned about PHP's ubiquity, someone followed up that this was no longer the case, and that many other languages are now commonly usable on web hosts too. What programming language; a. Would suit a developer who prefers C#. b. Is available to run on many web hosts.

    Read the article

  • What is the recommended MongoDB schema for this quiz-engine scenario?

    - by hughesdan
    I'm working on a quiz engine for learning a foreign language. The engine shows users four images simultaneously and then plays an audio file. The user has to match the audio to the correct image. Below is my MongoDB document structure. Each document consists of an image file reference and an array of references to audio files that match that image. To generate a quiz instance I select four documents at random, show the images and then play one audio file from the four documents at random. The next step in my application development is to decide on the best document schema for storing user guesses. There are several requirements to consider: I need to be able to report statistics at a user level. For example, total correct answers, total guesses, mean accuracy, etc) I need to be able to query images based on the user's learning progress. For example, select 4 documents where guess count is 10 and accuracy is <=0.50. The schema needs to be optimized for fast quiz generation. The schema must not cause future scaling issues vis a vis document size. Assume 1mm users who make an average of 1000 guesses. Given all of this as background information, what would be the recommended schema? For example, would you store each guess in the Image document or perhaps in a User document (not shown) or a new document collection created for logging guesses? Would you recommend logging the raw guess data or would you pre-compute statistics by incrementing counters within the relevant document? Schema for Image Collection: _id "505bcc7a45c978be24000005" date 2012-09-21 02:10:02 UTC imageFileName "BD3E134A-C7B3-4405-9004-ED573DF477FE-29879-0000395CF1091601" random 0.26997075392864645 user "2A8761E4-C13A-470E-A759-91432D61B6AF-25982-0000352D853511AF" audioFiles [ 0 { audioFileName "C3669719-9F0A-4EB5-A791-2C00486665ED-30305-000039A3FDA7DCD2" user "2A8761E4-C13A-470E-A759-91432D61B6AF-25982-0000352D853511AF" audioLanguage "English" date 2012-09-22 01:15:04 UTC } 1 { audioFileName "C3669719-9F0A-4EB5-A791-2C00486665ED-30305-000039A3FDA7DCD2" user "2A8761E4-C13A-470E-A759-91432D61B6AF-25982-0000352D853511AF" audioLanguage "Spanish" date 2012-09-22 01:17:04 UTC } ]

    Read the article

  • Web Service Standard Complexity

    Are we over-standardizing web services and hindering their adoption? No, and in fact I feel that it is helping its adoption in the modern corporate world. Standards, although they can be daunting and tedious, provide a universal framework to which we all can operate in and around. These frameworks provide a common interface for all of to use when interaction with various computing environments so that data can be transfer freely.  Standards are protocols in which computers communicate with one another. If we take this to the living world, the united nations hires interprets for all each countries dignitaries so that they can understand what other countries are talking about. Imagine if the president of the United States wanted to talk to the ruler of China. How would these to communicate? The interpreter would translate data back and forth acting as in intermediary using both standard American English and Chinese. Without knowing the standards in either language no one would be able to communicate. Even though we work within the framework of standards does not mean that we are stuck with these standards. As technology evolves all standards will be out of touch, and when this occurs standards need to be refactored or replaced with new standards that are current with the technology at that time. How else are we as developers and the technology going to grow? What do you guys think?

    Read the article

  • I can't see how a mature agile team requires any *management*?

    - by ashy_32bit
    After a recent heated debate over Scrum, I realized my problem is that I think of management as a quite unnecessary and redundant activity in a fully agile team. I believe a mature Agile team does not require management or any non-technical decision making process of whatsoever. To my (apparently erring) eyes it is more than obvious that the only one suitable and capable of managing a mature development team is their coach (and that being the most technically competent colleague with proper communication skills). I can't imagine how a Scrum master can contribute to such a team. I am having a great difficulty realizing and understanding the value of such things as Scrum and manager as someone who is not a veteran developer but is well skilled in planning the production cycles when a coach exists in the team. What does that even mean? How on earth someone with no edge-skills of development can manage a highly technical team? Perhaps management here means something else? I see management as a total waste of time and a by-product of immaturity. In my understanding a mature team is fully self-managing. Apparently I'm mistaken since many great people say the contrary but I can't convince myself.

    Read the article

  • 2d game view camera zoom, rotation & offset using 'Filter' / 'Shader' processing?

    - by Arthur Wulf White
    I wish to add the ability to zoom-in, zoom-out, rotate and move the view in a top-down view over a collection of points and lines in a large 2d map. I split the map into a grid so I only need to render the points that are 'near' the camera. My question is, how do I render a point A(Xp,Yp) assuming the following details: Offset of the camera pov from the origin of the map is: Xc, Yc Meaning the camera center is positioned on top of that point. If there's a point in Xc, Yc it is positioned in the center of the screen. The rotation angle is: alpha The scale is: S Read my answer first. I am thinking there is more optimized solution, thanks. My question is how to include the following improvement: I read in the AS3 Bible book that: In regards to ShaderInput, You can use these methods to coerce Pixel Bender to crunch huge sets of data masquerading as images, without doing too much work on the ActionScript side to make them look like images. Meaning if I am performing the same linear function on a lot of items, I can do it all at once if I use Shaders correctly and save processing time. Does anyone know how that is accomplished? Here is a sample of what I mean: http://wonderfl.net/c/eFp0/

    Read the article

  • Template syntax for users - is there a right way to do it?

    - by RickM
    Ok, I'm in the middle of building a saas system, and as part of that, the hosted clients need to be able to edit certain layout templates, baqsically just html, css and javascript files. I'm obviously going to be wanting to use a template syntax here as it would be dumb to let people execute PHP code, so in this instance template syntax does need to be used. I know that in the grand scale of things, this is a very minor thing, but what template syntax do you use, and why? Is there one that's considered better than others? I've seen all sorts being used with no real consistency, for example: Smarty Style: {$someVar} {foreach from="foo" item="bar"} {$bar.food} {/foreach} ASP Style: {% someVar %} {% foreach foo as bar %} {% bar.food %} {% endforeach %} HTML Style: <someVar> <foreach from="foo" item="bar"> <bar:food> </foreach> PyroCMS/FuelPHP "LEX" Style: {{ someVar }} {{ foreach from="foo" item="bar" }} {{ bar:food }} {{ endforeach }} Obviously these arent 100% accurate (for example, LEX is used alongside PHP for loops), and are only to give you an example of what I mean. What, in your opinion would be the best one (if any) to go with. I ask this bearing in mind that people using this are likely to be novice users. I did look around at a bunch of hosted CMS and E-Commerce systems as these seem to make use of user-editable templates, and most seem to be using some form of their own syntax. I should note that whatever style I end up going with, it will be with a custom template handler due to the complexity of the system and how template files are stored. Plus I'd not want to touch the likes of Smarty with a barge pole!

    Read the article

  • Touchpad and Keyboard both stop working after long uptime

    - by Sepero
    I have an Asus N53SM laptop that I leave running for several weeks at a time. I never put it in hibernate or suspend, I only close the lid when I'm not using it. After a few days or weeks of running, the touchpad and keyboard will Both lock up (at the same time) for no apparent reason. I could be just surfing the internet when it happens. The touchpad and keyboard seem to only lock up when I'm actively using the laptop (not when idle), which may mean it's related to something I press, but I'm not sure? The touchpad never locks or unlocks when Pressing FN and the designated touchpad lock key (it does not seem to work on Linux). While the touchpad and keyboard are locked, I am able to plug in my USB mouse and successfully use it to control the screen cursor. I can also remotely get into the system with vnc and ssh, everything seems to run fine there as well. No processes appear out of control. It's just the laptops physical touchpad and keyboard that are locking up. How might I go about diagnosing this problem? What system logs to look at? (anything specific to look for in them?) Perhaps I should try reloading some modules? Any thing else I should inspect?

    Read the article

  • Weird Screen while booting to install, while installing and after the install...and then the "panic occured" error

    - by Klyn
    I've decided to install ubuntu but neither ubuntu or any other linux distro won't even get to the desktop screen or work after getting there. On windows 8, everything is just fine. my new video card works perfectly and I have no problem with anything about it. then when I try to boot from ubuntu with wubi or with usb everything goes like this: 1) Grub screen...no problem at all, colors are just fine everything looks okay 2) and then linux boot screen...weird background color, over the backround there are vertical stripes of red-orange dots. but on the ubuntu logo and text, there are no dots at all! -I mean its shape is perfect- 3) desktop is about the start but * vertical stripes of red colored dots are all over the unity screen*. then when I click on ubuntu's menu, it usually switches to black screen saying something about "panic occured"...and then it restarts or it gives no respond at all. problems started after putting hd 6570 video card on my asus m5a78lm-lx video card which has amd phenom II X4 processor on it. I've searched to find something but there was no similar question that's why I'm almost sure it is kind of unique. again, I'm writing on Windows 8 right now and everything works and looks perfect. so far I've updated bios and anyone knows anything to solve this?

    Read the article

  • Is "send us a page with code" a typical interview requirement?

    - by acm
    Recently I was asked to show "a page with code" for a job interview. Being mainly a back-end programmer, and that's the position I applied for, I first said to the person I was talking to exactly that: PHP is executed at the server and therefore not visible by just giving a "page". However, following their desire, I sent links to the pages I've worked on before. Obviously they couldn't see anything except for the HTML, CSS, JS... They said it was not enough, they could not see the PHP. Understanding that they probably just wanted to know my skills and/or interest I sent them my Stack Overflow profile. Among all my questions and answers, most of them with code, certainly the PHP is there. But it seems this is not what they wanted. Well, I don't have any code put together that I can simply publish for someone to see. And I would never do it for the code I have deployed, obviously. So my question is/are: What does "send us a page with code" mean? What should I send? Is this a typical interview requirement?

    Read the article

  • Cannot boot: FGLRX 8.780 + Kernel 2.6.35-25

    - by pluc
    The situation before this all happened is pretty standard. I have a HP Pavillion dv5 laptop with an ATI Mobility Radeon 4200 series. It always worked fine with Ubuntu for as long as I can remember. However, at one point, something happened and truly made a majestic mess of things. It might've been extra repos I enabled with Ubuntu Tweak - I do not know. But something made it so that my system would not boot any longer. And when I say "won't boot", this is what I mean: - Durning a normal bootup, any entries (except Windows) selected with GRUB (or BURG, not even sure which one I'm using anymore) will spawn the Ubuntu loading screen - then try to start X (or GDM) 5 times. The screen goes to dark, black and back to the Ubuntu loading screen. Then it just stays there until I spawn another TTY. I have no idea what is happening or why. There are no errors in my logs, and I'm truly at a loss here. I've linked three files: Xorg.0.log, the output of dmesg and the GDM log: Xorg.0.log: http://ubuntu.pastebin.com/tpVKc2tc dmesg: ubuntu.pastebin.com/Nd5aYj45 gdm's :0.log: couldn't post due to lack of points :( Let me know if any of you more knowledgeable folks can restore some sanity in my life. Any help is greatly apreciated.

    Read the article

  • Inspiring People

    - by barrem23
    So I work with a few people that I feel are intelligent but don't seem to be working out well. After working with them for a while I have seen the flashes of brilliance but mostly I see a reliance on others. What I mean by this is that most times it seems like at the first moment of trouble they go ask for help. Now personally I am all for helping and spend a significant portion of time helping others with whatever they need, but after helping others for so long I have noticed a disturbing trend. These people seem terrified that they might make a mistake and because of this they don't try. So my question is how can I motivate someone who is afraid of making a mistake? In my career I have always learned the most by making mistakes and learning from them. Personally I feel that if I hadn't learned so much I would never have made it as far as I have. So how can I get them to discover that they have the ability to figure it out themselves and that if they make a mistake and learn from it they will be better off. I feel that if I can discover some way to properly motivate them that we all will be better off.

    Read the article

  • Transformation?

    - by Joe G
    I started working at Oracle in 1997.  Since then, we (and most everyone) have been talking about transforming finance operations....but what does that mean exactly?  From my perspective, I thought it meant eliminate waste and menial tasks and giving your finance team more time to work on more strategic things.  That seems logical and simplistic, but how much progress have finance teams (and their IT departments) really made over the past fifteen years? I have yet to talk to a customer that doesn't have one amusing task that makes me chuckle.  Sometimes they still print hard copies of transactions to "file," or sometimes they print 700 pages of data to "analyze," or sometimes they cut and paste from one or more reports into a spreadsheet.  Upon hearing these things, my first question is always, "Why do you do that?" to which their response is rarely the same.    Sometimes it's related to trust (both the employee and the system).  Sometimes, it's habit-based.  And sometimes it is just impossible to accomplish the end result without some manual effort. I will say that I used to print nearly everything that I needed to review.  Partly, because I liked having the ability to scribble notes on the paper, and partly, because it was uncomfortable to read online.  However, I have changed. Rarely do I print anything anymore.  It's easier for me to read and notate online, and well, I guess I've just changed my habits. So where do you think our resistance to change comes from?  Is it truly deficits in our systems, or is it our own personal resistance to change?  What's your most annoying & untransformed task?

    Read the article

  • Why would he say "We don't want to support MVC3"?

    - by MadBurn
    I work in a small shop at a fairly big company doing intranet web applications. By small, I mean there is 1 other guy in my position... and he graduated with me last December. (we aren't the only IT, but the only ones in our field) We are switching out an old COBOL system and converting it's only used application suite to a Web App. My company has contracted to a Web Application firm to help with this process who has chosen ASP.NET MVC, during one of the important meetings I asked if they will be using MVC2 or MVC3. Their lead developer said: "MVC2, we don't want to support MVC3. haha" My question is, why is this? This was several months ago and I've been doing extensive and self training gearing up for the MVC switch. From everything I am understanding, MVC3 is just like MVC2 if you don't use Razor and it fixes a number of smaller bugs that MVC2 had. So in my eyes, I can't see any reason to NOT use MCV3. There has to be something I'm missing. Since I don't really have any mentors to turn to in the real world, I'm coming here. What problems are there with MVC3 that might possibly lead him to say this that I'm missing?

    Read the article

  • Bring on the Cheer, Oracle’s Q3 is Here

    - by Kristin Rose
    November is long gone and December is near… this must mean OPN’s Q2 Winter Wrap-Up is here! Listed below are just a few of the highlights from Oracle’s past three months… Yet another successful Oracle OpenWorld 2012 and the launch of our first ever Oracle PartnerNetwork Exchange program! Get the recap. Our exciting Java Embedded @ JavaOne event. Get the low-down here! The debut of our new Oracle Cloud programs for partners, which have already created some awesome buzz in the Channel. Check out the CRN article, and don’t forget to watch the Cloud Programs Overview video and visit our OPN Cloud Knowledge Zone! On the product front, Oracle’s Sun ZFS Storage Appliance was awarded the 2012 Tech Innovator and Enterprise App Award by CRN. Read the full article. Oracle partner, Hitachi Consulting, reached OPN’s premier Diamond Level status. Read more. Was Oracle part of your September, October or November highlights? If so, leave us a comment below, we’d love to feature your story! Also, don’t forget to share the love by re-tweeting this post on Twitter or “liking” this post on Facebook! Stay Warm, The OPN Communications Team 

    Read the article

  • How should I group these variables?

    - by stariz77
    I have a shape that will be defined by: char s_type; char color; double height; double width; These variables are scanned in from a request string sent to my server and passed into my printing function, which then prints out the shape. Currently they are just local variables sitting in my main(); however, I was wondering if there would be any advantage in creating a struct containing these variables, and then passing the struct to my printing function? or how else might I improve my program's structure/style, would passing a struct by reference have any kind of performance benefit if there were many requests and therefore many printing function calls? printer(char st, char cr, double ht, double wd); int main() { // Other main functionality. char s_type; char color; double height; double width; sscanf (serv_req, "GET /%c/%c/%lf/%lf", &s_type, &color, &height, &width); printer(s_type, color, height, width); // Other main functionality. return 0; } It seemed "neater" if I had a struct or something that didn't leave me with declarations in the middle of everything else going on in main. I'm interested in structure/style as well as performance. EDIT: didn't mean to put printer declaration inside main.

    Read the article

  • Open Source Highlight: namebench

    - by eddraper
    DNS is a big deal.  Even small incremental changes to improve its performance can yield significant value due to the vast quantity of look-ups required when using the internet.  Until now, It’s always been one of those things I had to kinda take on faith… was my ISP doing a good job?  Are those public DNS server really that much faster?  What about security and privacy concerns? Let me introduce you to namebench.  This is the kinda tool I really love – one that immediately delivers value and is almost over-the-top OCD in its attention to detail. Trust me, this tool is utterly ruthless in it’s quest for getting it right – you’re not left with a big question mark after it presents its data.  The results are conclusive and actionable.  Here’s what is does: It hunts down the fastest DNS servers from your desktop that it can find using thousands of requests.  No, it doesn’t pop up this little dialog in 10 seconds to give you some “off the cuff” answer from a handful of providers.  It takes the better part of 10-15 minutes to run.  When it finishes, it presents you with a veritable horn-o-plenty of data.  Mean response duration, response distribution, bad data,  no stone is left un-turned. Check it out.  You’ll dig it.

    Read the article

  • How often do you look for code examples?

    - by Newly Insecure
    I am a comp sci student with several years of experience in C and C++, and for the last few years I've been constantly working with Java/Objective C doing app dev and now I have switched to web dev and am mainly focused on ruby on rails and I came to the realization that (as with app dev, really) I reference other code wayyyy too much. I constantly google functionality for lots of things I imagine I should be able to do from scratch and it's really cracked my confidence a bit. Basic fundamentals are not an issue, I hate to use this as an example but I can run through javabat in both java/python at a sprint - obviously not an accomplishment and but what I mean to say is I have a strong base for the fundamentals I think? I was wondering how often you guys reference other code and does it just boil down to a lack of memorization of intricate tasks on my part? I know what I need to use typically but reference syntax constantly. Would love some advice and input on this, as it has been holding me back pretty solidly in terms of looking for work in this field even though I'm finishing my degree. My main reason for asking is not really about employment, but more that I don't want to be the only guy at a hackathon not hammering out nonstop code and sitting there with 20 google/github tabs open, and I have refrained from attending any due to a slight lack of confidence... tl;dr: I google for code examples for basically ALL semi advanced/advanced functionality, how to fix this and do you do as well?

    Read the article

  • Two Sessions All Humans Should Watch Right Now

    - by Geertjan
    At conferences, I definitely prefer technical sessions over any other kind of session. That's partly because I want to walk away from a conference with new libraries and APIs to play with, such as the AT&T ARO tool that I've been blogging about over the past few days thanks to being introduced to it in a great session by Doug Sillars at Oredev, in Malmo, Sweden. I only say the above to set the scene. And the scene is that I avoid sessions that deal with "agile topics" or whatever that means. I mean those sessions where you're meant to reflect on some way you're developing nothing in particular and then come away with new ways of doing that. I avoid those. Not because I don't necessarily like those or think I have nothing to learn, both of which I don't (or do, depending on how you read double negatives), but because there are so many sessions to attend that I focus on those that actually give me more technical knowledge that I can do something with immediately. Having said all that, here's two absolutely wonderful sessions (and probably many more but I really liked these two) presented at Oredev over the last few days, one by JB Rainsberger and the other by Woody Zuill, both very nice people who I met for the first time during the last few days, and who aren't paying me to promote them, and who're still struggling to figure out how to say my name. Whether you're a developer or manager or whatever you are, take this on trust, and simply watch these screencasts, hey, at most you're going to lose two hours of your life that you would've spent doing something else: Speaking for myself, I'm going to be watching both these presentations again several times in my life, that's for sure.

    Read the article

  • Updating, etc., automatically

    - by Steve D
    Is there a way to set up Ubuntu 12.04 (or earlier versions) so that all recommended updates are done automatically, say once a week? When I say automatically, I mean no password entry or user intervention required. This sounds like a stupid request, so let me tell why I'm asking. My grandfather knows nothing about computers; he uses his solely to read Yahoo! mail. I want to get rid of his clunky, spyware-ridden Windows XP and install Ubuntu. I want to set it up so when he turns the computer on, after a couple minutes, voila!, Yahoo! mail, already signed in, ready to go. The problem is I don't want to have to go over there every week or so and make sure everything is up-to-date, he hasn't accidentally installed any spyware, etc. So can this be done? Is this the best way to set things up for my grandfather? Are there other things I should be worried about when it comes to keeping things hassle-free for him? Please don't post anything like "why not teach him how to... blah blah blah". My grandfather is 80 years old and has made it clear email is the only thing he will ever use a computer for! Thanks!

    Read the article

  • How should I compress a file with multiple bytes that are the same with Huffman coding?

    - by Omega
    On my great quest for compressing/decompressing files with a Java implementation of Huffman coding (http://en.wikipedia.org/wiki/Huffman_coding) for a school assignment, I am now at the point of building a list of prefix codes. Such codes are used when decompressing a file. Basically, the code is made of zeroes and ones, that are used to follow a path in a Huffman tree (left or right) for, ultimately, finding a byte. In this Wikipedia image, to reach the character m the prefix code would be 0111 The idea is that when you compress the file, you will basically convert all the bytes of the file into prefix codes instead (they tend to be smaller than 8 bits, so there's some gain). So every time the character m appears in a file (which in binary is actually 1101101), it will be replaced by 0111 (if we used the tree above). Therefore, 1101101110110111011011101101 becomes 0111011101110111 in the compressed file. I'm okay with that. But what if the following happens: In the file to be compressed there exists only one unique byte, say 1101101. There are 1000 of such byte. Technically, the prefix code of such byte would be... none, because there is no path to follow, right? I mean, there is only one unique byte anyway, so the tree has just one node. Therefore, if the prefix code is none, I would not be able to write the prefix code in the compressed file, because, well, there is nothing to write. Which brings this problem: how would I compress/decompress such file if it is impossible to write a prefix code when compressing? (using Huffman coding, due to the school assignment's rules) This tutorial seems to explain a bit better about prefix codes: http://www.cprogramming.com/tutorial/computersciencetheory/huffman.html but doesn't seem to address this issue either.

    Read the article

  • X crashes and GNOME loses all its configuration

    - by Oli
    About every 3 days on my desktop (always on), X crashes, gdm restarts and it dumps me at a login screen. When I log in Gnome appears to have lost a lot of its settings: it plays sounds in weird places, UI elements look like they're from the 90s (GTK+ defaults) and it's generally pretty hideous. Note everything works fine. It's not like my profile doesn't exist because I can browse the internet fine (Firefox knows my bookmarks, history, passwords, etc) and my desktop is unscathed (apart from the icon theme). Manually restarting gdm doesn't fix this. I have to do a full reboot. Now I'm almost certain that this is a nvidia issue causing X to baulk (I've seen similarish threads on nvnews) and I'm happy with that (my fault for running their latest drivers all the time). What I'm concerned about is why Gnome looks so fugly. Is there anything I can do to force it to reload its settings without restarting the whole computer. Restarting is an issue for me as I run several daemons that other computers on the network depend upon. This is what I mean by ugly/fugly... Look at that scroll bar!

    Read the article

  • Who extends interfaces? And why?

    - by Gangnus
    AFAIK, my class extends parent classes and implements interfaces. But I run across a situation, where I can't use implements SomeInterface. It is the declaration of a generic types. For example: public interface CallsForGrow {...} public class GrowingArrayList <T implements CallsForGrow> // BAD, won't work! extends ArrayList<T> Here using implements is syntactically forbidden. I thought first, that using interface inside < is forbidden at all, but no. It is possible, I only have to use extends instead of implements. As a result, I am "extending" an interface. This another example works: public interface CallsForGrow {...} public class GrowingArrayList <T extends CallsForGrow> // this works! extends ArrayList<T> To me it seems as a syntactical inconsistancy. But maybe I don't understand some finesses of Java 6? Are there other places where I should extend interfaces? Should the interface, that I mean to extend, have some special features?

    Read the article

  • Do you think we will ever settle on a "standard" platform? [closed]

    - by GazTheDestroyer
    The recent explosion of phone platforms has depressed me (slightly), and made me wonder if we will ever reach any kind of standard for presentation? I don't mean language or IDE. Different languages have different strengths and I can see that there may always be a need for disparity, although I do note that languages are merging somewhat in functionality, with traditional imperitive languages like C++ now supporting things like lambdas. What I'm really talking about is a common presentation mechanism. Before smart phones and tablets came along, the web seemed to be finally becoming a reasonable platform for presenting an application that was globally accessible, not just geographically, but by platform too. Sure there are still (sometimes infuriating) implementation differences and quirks, but if you wrote a decent site you knew it could be accessed on anything from a PC to a phone to a C64 running the right software. "Write Once Run Anywhere" seemed to finally be becoming a reality. However, in the last few years we've seen an explosion of mobile operating systems, and the ubiquitous "app". A good site is no longer enough, you need a native "app", and of course we have a sudden massive disparity in OS, language, and APIs needed to write them as each battles for supremecy. It's kind of weird how the cycle of popularity goes. Mainframes with terminals - thin client. PC - thick client. Web browser - thin client. Phone app - thick(ish) client. I just wonder if you think there will ever be a global standard for clients, or whether the "shiny and different" cycle will always continue along with the battle of the tech du jour.

    Read the article

  • Why do VMs need to be "stack machines" or "register machines" etc.?

    - by Prog
    (This is an extremely newbie-ish question). I've been studying a little about Virtual Machines. Turns out a lot of them are designed very similarly to physical or theoretical computers. I read that the JVM for example, is a 'stack machine'. What that means (and correct me if I'm wrong) is that it stores all of it's 'temporary memory' on a stack, and makes operations on this stack for all of it's opcodes. For example, the source code 2 + 3 will be translated to bytecode similar to: push 2 push 3 add My question is this: JVMs are probably written using C/C++ and such. If so, why doesn't the JVM execute the following C code: 2 + 3..? I mean, why does it need a stack, or in other VMs 'registers' - like in a physical computer? The underlying physical CPU takes care of all of this. Why don't VM writers simply execute the interpreted bytecode with 'usual' instructions in the language the VM is programmed with? Why do VMs need to emulate hardware, when the actual hardware already does this for us? Again, very newbie-ish questions. Thanks for your help

    Read the article

< Previous Page | 668 669 670 671 672 673 674 675 676 677 678 679  | Next Page >