Search Results

Search found 10033 results on 402 pages for 'execution speed'.

Page 291/402 | < Previous Page | 287 288 289 290 291 292 293 294 295 296 297 298  | Next Page >

  • Need help identifing what resources (eg. In MIT OpenCourseWare) can help me prepare for a test [closed]

    - by jiewmeng
    I am entering uni soon. I can sit for a placement test to see if I elegible for exemptions. The details are http://www.comp.nus.edu.sg/undergraduates/TestScope11_12.html Or CS2100 Computer Organisation (please click title) The objective of this module is to familiarise students with the fundamentals of computing devices. Through this module students will understand the basics of data representation, and how the various parts of a computer work, separately and with each other. This allows students to understand the issues in computing devices, and how these issues affect the implementation of solutions. Topics covered include data representation systems, combinational and sequential circuit design techniques, assembly language, processor execution cycles, pipelining, memory hierarchy and input/output systems. Recommended Textbooks Digital Design: Principles and Practices [DDPP] by John F. Wakerly, Prentice-Hall. ISBN 0-13-324500-4. Computer Organizations and Design (The hardware/software interface) by David A. Patterson and John L. Hennessy. CS2105 Introduction to Computer Networks (please click title) This course aims to provide a broad introduction to computer networks and some appreciations of network application programming. It covers a range of topics including basic data communication and computer network concepts, protocols, networked computing concepts and principles, network applications development and network security. The emphasis of teaching is on the working principles and application of computer networks. As an integral part of the course, tutorials and practical assignments enforcing learning will also be given. These assignments provide an early exposure in network application programming and they should be able to complete by using personal computers and school's network facilities. Topics included: An overview of computer networks and the Internet Basic data communications Application layer Transport layer Network layer and routing Link layer and local area networks Recommended Textbook James F. Kurose & Keith W. Ross, Computer networking: A top-down approach featuring internet, Addison Wesley, 2001 I am wondering what resources eg. MIT OpenCourseWare or other universities resources are available to help he perpare for these particular modubles. I am thinking does the Networking one look like CCNA? The computer oragization. Its like electronics, assembly etc? I learnt some electronics in Poly but looking at the sample papers, uni looks very different... I have about 1 month to prepare if I want any chance of exempting from these modules :) any help?

    Read the article

  • 2D camera perspective projection from 3D coordinates -- HOW?

    - by Jack
    I am developing a camera for a 2D game with a top-down view that has depth. It's almost a 3D camera. Basically, every object has a Z even though it is in 2D, and similarly to parallax layers their position, scale and rotation speed vary based on their Z. I guess this would be a perspective projection. But I am having trouble converting the objects' 3D coordinates into the 2D space of the screen so that everything has correct perspective and scale. I never learned matrices though I did dig the topic a bit today. I tried without using matrices thanks to this article but every attempt gave awkward results. I'm using ActionScript 3 and Flash 11+ (Starling), where the screen coordinates work like this: Left-handed coordinates system illustration I can explain further what I did if you want to help me sort out what's wrong, or you can directly tell me how you would do it properly. In case you prefer the former, read on. These are images showing the formulas I used: upload.wikimedia.org/math/1/c/8/1c89722619b756d05adb4ea38ee6f62b.png upload.wikimedia.org/math/d/4/0/d4069770c68cb8f1aa4b5cfc57e81bc3.png (Sorry new users can't post images, but both are from the wikipedia article linked above, section "Perspective projection". That's where you'll find what all variables mean, too) The long formula is greatly simplified because I believe a normal top-down 2D camera has no X/Y/Z rotation values (correct ?). Then it becomes d = a - c. Still, I can't get it to work. Maybe you could explain what numbers I should put in a(xyz), c(xyz), theta(xyz), and particularly, e(xyz) ? I don't quite get how e is different than c in my case. c.z is also an issue to me. If the Z of the camera's target object is 0, should the camera's Z be something like -600 ? ( = focal length of 600) Whatever I do, it's wrong. I only got it to work when I used arbitrary calculations that "looked" right, like most cameras with parallax layers seem to do, but that's fake! ;) If I want objects to travel between Z layers I might as well do it right. :) Thanks a lot for your help!

    Read the article

  • Behaviour Trees with irregular updates

    - by Robominister
    I'm interested in behaviour trees that aren't iterated every game tick, but every so often. (Edit: the tree could specify how many frames within the main game loop to wait before running its tick function again). Every theoretical implementation I have seen of behaviour trees talks of the tree search being carried out every game update - which seems necessary, because a leaf node (eg a behaviour, like 'return to base') needs to be constantly checked to see if is still running, failed or completed. Can anyone suggest how I might start implementing a tree that isnt run every tick, or point me in the direction of good material specific to this case (I am struggling to find anything)? My thoughts so far: action leaf nodes (when they start) must only push some kind of action object onto a list for an entity, rather than directly calling any code that makes the entity do something. The list of actions for the entity would be run every frame (update any that need to run, pop any that have completed from the list). the return state from a given action must be fed back into the tree, so that when we run the tree iteration again (and reach the same action leaf node - so the tree has so far determined that we ought to still be trying this action) - that the action has completed, or is still running etc. If my actual action code is running from an action list on an entity, then I possibly need to cancel previously running actions in the list - i am thinking that I can just delete the entire stack of queued up actions. I've seen the idea of ActionLists which block lower priority actions when a higher priority one is added, but this seems like very close logic to behaviour trees, and I dont want to be duplicating behaviour. This leaves me with some questions 1) How would I feed the action return state back into the tree? Its obvious I need to store some information relating to 'currently executing actions' on the entity, and check that in the tree tick, but I can't imagine how. 2) Does having a seperate behaviour tree (for deciding behaviour) and action list (for carrying out actual queued up actions) sound like a reasonable approach? 3) Is the approach of updating a behaviour tree irregularly actually used by anyone? It seems like a nice idea for budgeting ai search time when you have a lot of ai entities to process. (Edit) - I am also thinking about storing a single instance of a given behaviour tree in memory, and providing it by reference to any entity that uses it. So any information about what action was last selected for execution on an entity must be stored in a data context relative to the entity (which the tree can check). (I am probably answering my own questions as i go!) I hope I have expressed my questions adequately! Thanks in advance for any help :)

    Read the article

  • How to implement an intelligent enemy in a shoot-em-up?

    - by bummzack
    Imagine a very simple shoot-em-up, something we all know: You're the player (green). Your movement is restricted to the X axis. Our enemy (or enemies) is at the top of the screen, his movement is also restricted to the X axis. The player fires bullets (yellow) at the enemy. I'd like to implement an A.I. for the enemy that should be really good at avoiding the players bullets. My first idea was to divide the screen into discrete sections and assign weights to them: There are two weights: The "bullet-weight" (grey) is the danger imposed by a bullet. The closer the bullet is to the enemy, the higher the "bullet-weight" (0..1, where 1 is highest danger). Lanes without a bullet have a weight of 0. The second weight is the "distance-weight" (lime-green). For every lane I add 0.2 movement cost (this value is kinda arbitrary now and could be tweaked). Then I simply add the weights (white) and go to the lane with the lowest weight (red). But this approach has an obvious flaw, because it can easily miss local minima as the optimal place to go would be simply between two incoming bullets (as denoted with the white arrow). So here's what I'm looking for: Should find a way through bullet-storm, even when there's no place that doesn't impose a threat of a bullet. Enemy can reliably dodge bullets by picking an optimal (or almost optimal) solution. Algorithm should be able to factor in bullet movement speed (as they might move with different velocities). Ways to tweak the algorithm so that different levels of difficulty can be applied (dumb to super-intelligent enemies). Algorithm should allow different goals, as the enemy doesn't only want to evade bullets, he should also be able to shoot the player. That means that positions where the enemy can fire at the player should be preferred when dodging bullets. So how would you tackle this? Contrary to other games of this genre, I'd like to have only a few, but very "skilled" enemies instead of masses of dumb enemies.

    Read the article

  • "Hello World" in C++ AMP

    - by Daniel Moth
    Some say that the equivalent of "hello world" code in the data parallel world is matrix multiplication :) Below is the before C++ AMP and after C++ AMP code. For more on what it all means, watch the recording of my C++ AMP introduction (the example below is part of the session). void MatrixMultiply(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W ) { for (int y = 0; y < M; y++) { for (int x = 0; x < N; x++) { float sum = 0; for(int i = 0; i < W; i++) { sum += vA[y * W + i] * vB[i * N + x]; } vC[y * N + x] = sum; } } } Change the function to use C++ AMP and hence offload the computation to the GPU, and now the calling code (which I am not showing) needs no changes and the overall operation gives you really nice speed up for large datasets…  #include <amp.h> using namespace concurrency; void MatrixMultiply(vector<float>& vC, const vector<float>& vA, const vector<float>& vB, int M, int N, int W ) { array_view<const float,2> a(M, W, vA); array_view<const float,2> b(W, N, vB); array_view<writeonly<float>,2> c(M, N, vC); parallel_for_each( c.grid, [=](index<2> idx) mutable restrict(direct3d) { float sum = 0; for(int i = 0; i < a.x; i++) { sum += a(idx.y, i) * b(i, idx.x); } c[idx] = sum; } ); } Again, you can understand the elements above, by using my C++ AMP presentation slides and recording… Stay tuned for more… Comments about this post welcome at the original blog.

    Read the article

  • Ivy bridge i3 recognized as Xeon e3-1200

    - by user287072
    The situation: I've got a Ivy bridge i3 3225 which is being recognized as a Xeon e3-1200 series cpu by Ubuntu 14.04 64bit. The problem: cpu fan makes more noise than necessary (under dual-boot Win8 the fans are off), cannot install the intel graphics drivers from 01.org. Goals: - find a fix for the load fans could be they are not CPU related, I've tried some fan controller packages, but they made no difference. - get the intel graphics to install (this now fails as xeon cpu's are not supported, I got the package working on a i5 laptop) - get to know some more about how hardware recognition works Tried so far: - a reinstall of Ubuntu, but it was recognized again as a Xeon cpu. - different fan control packages, but they either do not recognized the fans, or just keep fan speed to high. Any pointers as how to get Ubuntu recognized it are more than welcome. lspci -nnQ 00:00.0 Host bridge [0600]: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor DRAM Controller [8086:0150] (rev 09) 00:01.0 PCI bridge [0604]: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor PCI Express Root Port [8086:0151] (rev 09) 00:14.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller [8086:1e31] (rev 04) 00:16.0 Communication controller [0780]: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 [8086:1e3a] (rev 04) 00:1a.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 [8086:1e2d] (rev 04) 00:1b.0 Audio device [0403]: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller [8086:1e20] (rev 04) 00:1c.0 PCI bridge [0604]: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 [8086:1e10] (rev c4) 00:1c.5 PCI bridge [0604]: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 6 [8086:1e1a] (rev c4) 00:1c.6 PCI bridge [0604]: Intel Corporation 82801 PCI Bridge [8086:244e] (rev c4) 00:1d.0 USB controller [0c03]: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 [8086:1e26] (rev 04) 00:1f.0 ISA bridge [0601]: Intel Corporation Z77 Express Chipset LPC Controller [8086:1e44] (rev 04) 00:1f.2 SATA controller [0106]: Intel Corporation 7 Series/C210 Series Chipset Family 6-port SATA Controller [AHCI mode] [8086:1e02] (rev 04) 00:1f.3 SMBus [0c05]: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller [8086:1e22] (rev 04) 01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK106 [GeForce GTX 660] [10de:11c0] (rev a1) 01:00.1 Audio device [0403]: NVIDIA Corporation GK106 HDMI Audio Controller [10de:0e0b] (rev a1) 03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 09) 04:00.0 PCI bridge [0604]: ASMedia Technology Inc. ASM1083/1085 PCIe to PCI Bridge [1b21:1080] (rev 03)

    Read the article

  • Workflow 4.5 is Awesome, cant wait for 5.0!

    - by JoshReuben
    About 2 years ago I wrote a blog post describing what I would like to see in Workflow vnext: http://geekswithblogs.net/JoshReuben/archive/2010/08/25/workflow-4.0---not-there-yet.aspx At the time WF 4.0 was a little rough around the edges – the State Machine was on codeplex and people were simulating state machines with Flowcharts. Last year I built a near- realtime machine management system using WF 4.0.1 – its managing the internal operations of this device: http://landanano.com/products/commercial   Well WF 4.5 has come a long way – many of my gripes have been addressed: C# expressions - no more VB 'AndAlso' clauses state machine awesomeness - can query current state many designer improvements - Document Outline is so much more succinct than Designer! Separate WCF Service Contract interfaces and ability to generate activities from contract operations ability to rehydrate to updated flow definitions via DynamicUpdateMap and WorkflowIdentity you can read about the new features here: http://msdn.microsoft.com/en-us/library/hh305677(VS.110).aspx   2013 could be the year of Workflow evangelism for .NET, as it comes together as the DSL language. Eg on Azure it could be used to graphically orchestrate between WebRoles, WorkerRoles and AppFabric Queues and the ServiceBus – that would be grand.   Here’s a list of things I’d like to see in Workflow 5.0: Stronger Parallelism support for true multithreaded workflows . A Workflow executes on a single thread – wouldn’t it be great if we had the ability to model TPL DataFlow? Parallel is not really parallel, just allows AsyncCodeActivity.     support for recursion an ExpressionTree activity with an editor design surface a math activity pack return of application level protocol (3.51 WF services) – automatically expose a state machine as a WCF service with bookmark Receive activities generated from OperationContract automatically placed in state transition triggers. A new HTML5 ActivityDesigner control – support with different CSS3  skinnable hooks,  remote connectivity (had to roll my own) A data flow view – crucial to understanding the big picture Ability to refactor a Sequence to custom activity in a separate .xaml file – like Expression Blend does for UserControl state machine global error handling - if all states goto an error state, you quickly get visual spagetti. Now you could nest a state machine, but what if you want an application level protocol whereby each state exposes certain WCF ops. DSL RAD editing - Make the Document Outline into a DSL editor for adding activities  – For WF to really succeed as a higher level of abstraction, It needs to be more productive than raw coding - drag & drop on the designer is currently too slow compared to just typing code. Extensible Wizard API - for pluggable WF editor experience other execution models beyond Sequence, Flowchart & StateMachine: SSIS, Behavior Trees,  Wolfram Model tool – surprise us! improvements to Designer debugging API - SourceLocation is tied to XAML file line number and char position, and ModelService access seems convoluted - why not leverage WPF LogicalTreeHelper / VisualTreeHelper ? Workflow Team , keep on rocking!

    Read the article

  • Is it okay to have people with multiple roles in a Scrum team?

    - by Wayne M
    I'm evaluating some Agile-style methodologies for possible introduction to my team. With Scrum, is it allowable to have the same person perform multiple roles? We have a small team of four developers and a web designer; we don't really have a lead (I fulfill this role), QA testers or business analysts, and all of our development tasks come from the CIO. Automated testing is seen as a total waste of time, and everything focuses on speed and not quality. What will happen is the CIO will come up with a development task (whether a feature or a bug) and give it to a developer (not to the whole team, to an individual, often in private or out of the blue) who is then expected to get it completed. The CIO doesn't gather requirements beyond the initial idea (and this has bitten us before as we'll implement something only to find out that none of the end users can use the feature, because they weren't consulted or even informed about it before we developed it, and in a panic we'll be told to revert the change) but requires say in/approval of everything that we do. First things first, is a Scrum style something to consider to introduce some standards and practices? From reading, Scrum seems to rely on a bit more trust and communication and focuses more on project management than on development, which is something we are completely devoid of as we don't have any semblance of project management at present. Second, if it can work is it unreasonable for someone, let's say myself, to act as both ScrumMaster and a developer? Or for a developer to also be the Product Owner (although chances are this will be the CIO, who isn't a developer)? I realize the Scrum Master and the Product Owner should be different people but at the same time I don't think we have anyone who has the qualities of a Product Owner (chances are it would turn into a "I need all these stories, I don't care how but get it done" type of deal and/or any freeze would be unfrozen on a whim). It seems to me that I might need to pick and choose pieces of Scrum/XP/Lean to compensate for how things are done currently, as it's highly unlikely that the mentality can be changed; for instance Pair Programming would never fly (seen as a waste, you get half the tasks done if you need two people for everything), TDD would be a hard sell, but short cycles would be welcomed.

    Read the article

  • The State of the Internet -- Retail Edition

    - by David Dorf
    Over at Business Insider, there's a great presentation on the State of the Internet done in the Mary Meeker style.  Its 138 slides so I took the liberty of condensing it down to the 15 slides that directly apply to the retail industry.  However, I strongly recommend looking at the entire deck when you have time.  And while you're at it, Business Insider just launched a retail portal that's dedicated to retail industry content.  Please check it out as well.  My take-aways are below after the slide show. &amp;amp;amp;amp;lt;span id=&amp;amp;amp;amp;quot;XinhaEditingPostion&amp;amp;amp;amp;quot;&amp;amp;amp;amp;gt;&amp;amp;amp;amp;lt;/span&amp;amp;amp;amp;gt; [Source: Business Insider] Here are a few things I took away from the statistics: Facebook and Twitter are in their infancy.  While all retailers should have social programs, search is still the driver and therefore should receive the lions share of investment.  Facebook referrals are up 92% year-over-year, but Google still does 80% of the referrals. E-commerce continues to grow at breakneck speed, but in-store commerce is still king. Stores are not showrooms yet.  And social commerce pure-plays like Gilt and Groupon are tiny but worthy of some attention. There are more smartphones than PCs on the internet, and the disparity will continue to grow. PC growth will be flat and Tablet use will continue to grow. Mobile accounts for 12% of all internet traffic. A quarter of smartphone sales come from China, so anyone with a presence there better have a strong mobile strategy. 38% of people have used their smartphone to make a purchase, and many use their smartphones inside stores.  Smartphones are a critical consumer tool for shopping. Mobile is starting to drive significant traffic to e-commerce sites, especially tablets.  Tablet strategies are crucial for retailers. Mobile payments from the likes of Paypal and Square are growing quickly.  It will be interesting to see how NFC plays in this area. Mobile operating systems are losing market share to iOS and Android.  I wonder in Microsoft can finally make a dent? The internet is being dominated by mobile devices, and retailers had better have a strong mobile strategy to meet consumer demand.

    Read the article

  • Fixing a NoClassDefFoundError

    - by Chris Okyen
    I have some code: package ftc; import java.util.Scanner; public class Fer_To_Cel { public static void main(String[] argv) { // Scanner object to get the temp in degrees Farenheit Scanner keyboard = new Scanner(System.in); boolean isInt = true; // temporarily put as true in case the user enters a valid int the first time int degreesF = 0; // initialy set to 0 do { try { // Input the temperature text. System.out.print("\nPlease enter a temperature (integer number, no fractional part) in degrees Farenheit: "); degreesF = Integer.parseInt(keyboard.next()); // Get user input and Assign the far. temperature variable, which is casted from String to int. } // Let the user know in a user friendly notice that the value entered wasnt an int ( give int value range ) , and then give error log catch(java.lang.Exception e) { System.out.println("Sorry but you entered a non-int value ( needs to be between ( including ) -2,147,483,648 and 2,147,483,647 ).. \n"); e.printStackTrace(); isInt = false; } } while(!isInt); System.out.println(""); // print a new line. final int degreesC = (5*(degreesF-32)/9); // convert the degrees from F to C and store the resulting expression in degreesC // Print out a newline, then print what X degrees F is in Celcius. System.out.println("\n" + degreesF + " degrees Farenheit is " + degreesC + " degrees Celcius"); } } And The following error: C:\Program Files\Java\jdk1.7.0_06\bin>java Fer_To_Cel Exception in thread "main" java.lang.NoClassDefFoundError: Fer_To_Cel (wrong name: ftc/Fer_To_Cel) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:791) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:14 at java.net.URLClassLoader.defineClass(URLClassLoader.java:449) at java.net.URLClassLoader.access$100(URLClassLoader.java:71) at java.net.URLClassLoader$1.run(URLClassLoader.java:361) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:423) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:356) at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:480) The code compiled without compile errors, but presented errors during execution. Which leads me to two questions. I know Errors can be termed Compiler, Runtime and Logic Errors, but the NoClassDefFoundError inherits java.lang.LinkageError. Does that make it a Linker error, being niether of the three types of errors I listed, If I am right this is the answer. For someone else who obtains the singular .java file and compiles it, would this be the only way to solve this problem? Or can I (should I ) do/have done something to fix this problem? Basically, based on a basis of programming, is this a fault of me as the writer? Could this be done once on, my half and be distributed and not needed be done again?

    Read the article

  • SQL Azure Security: DoS Part II

    - by Herve Roggero
    Ah!  When you shoot yourself in the foot... a few times... it hurts! That's what I did on Sunday, to learn more about the behavior of the SQL Azure Denial Of Service prevention feature. This article is a short follow up to my last post on this feature. In this post, I will outline some of the lessons learned that were the result of testing the behavior of SQL Azure from two machines. From the standpoint of SQL Azure, they look like one machine since they are behind a NAT. All logins affected The first thing to note is that all the logins are affected. If you lock yourself out to a specific database, none of the logins will work on that database. In fact the database size becomes "--" in the SQL Azure Portal.   Less than 100 sessions I was able to see 50+ sessions being made in SQL Azure (by looking at sys.dm_exec_sessions) before being locked out. The the DoS feature appears to be triggered in part by the number of open sessions. I could not determine if the lockout is triggered by the speed at which connection requests are made however.   Other Databases Unaffected This was interesting... the DoS feature works at the database level. Other databases were available for me to use.   Just Wait Initially I thought that going through SQL Azure and connecting from there would reset the database and allow me to connect again. Unfortunately this doesn't seem to be the case. You will have to wait. And the more you lock yourself out, the more you will have to wait... The first time the database became available again within 30 seconds or so; the second time within 2-3 minutes and the third time... within 2-3 hours...   Successful Logins The DoS feature appears to engage only for valid logins. If you have a login failure, it doesn't seem to count. I ran a test with over 100 login failures without being locked.

    Read the article

  • SQL 2014 does data the way developers want

    - by Rob Farley
    A post I’ve been meaning to write for a while, good that it fits with this month’s T-SQL Tuesday, hosted by Joey D’Antoni (@jdanton) Ever since I got into databases, I’ve been a fan. I studied Pure Maths at university (as well as Computer Science), and am very comfortable with Set Theory, which undergirds relational database concepts. But I’ve also spent a long time as a developer, and appreciate that that databases don’t exactly fit within the stuff I learned in my first year of uni, particularly the “Algorithms and Data Structures” subject, in which we studied concepts like linked lists. Writing in languages like C, we used pointers to quickly move around data, without a database in sight. Of course, if we had a power failure all this data was lost, as it was only persisted in RAM. Perhaps it’s why I’m a fan of database internals, of indexes, latches, execution plans, and so on – the developer in me wants to be reassured that we’re getting to the data as efficiently as possible. Back when SQL Server 2005 was approaching, one of the big stories was around CLR. Many were saying that T-SQL stored procedures would be a thing of the past because we now had CLR, and that obviously going to be much faster than using the abstracted T-SQL. Around the same time, we were seeing technologies like Linq-to-SQL produce poor T-SQL equivalents, and developers had had a gutful. They wanted to move away from T-SQL, having lost trust in it. I was never one of those developers, because I’d looked under the covers and knew that despite being abstracted, T-SQL was still a good way of getting to data. It worked for me, appealing to both my Set Theory side and my Developer side. CLR hasn’t exactly become the default option for stored procedures, although there are plenty of situations where it can be useful for getting faster performance. SQL Server 2014 is different though, through Hekaton – its In-Memory OLTP environment. When you create a table using Hekaton (that is, a memory-optimized one), the table you create is the kind of thing you’d’ve made as a developer. It creates code in C leveraging structs and pointers and arrays, which it compiles into fast code. When you insert data into it, it creates a new instance of a struct in memory, and adds it to an array. When the insert is committed, a small write is made to the transaction to make sure it’s durable, but none of the locking and latching behaviour that typifies transactional systems is needed. Indexes are done using hashes and using bw-trees (which avoid locking through the use of pointers) and by handling each updates as a delete-and-insert. This is data the way that developers do it when they’re coding for performance – the way I was taught at university before I learned about databases. Being done in C, it compiles to very quick code, and although these tables don’t support every feature that regular SQL tables do, this is still an excellent direction that has been taken. @rob_farley

    Read the article

  • What is a good design model for my new class?

    - by user66662
    I am a beginning programmer who, after trying to manage over 2000 lines of procedural php code, now has discovered the value of OOP. I have read a few books to get me up to speed on the beginning theory, but would like some advice on practical application. So,for example, let's say there are two types of content objects - an ad and a calendar event. what my application does is scan different websites (a predefined list), and, when it finds an ad or an event, it extracts the data and saves it to a database. All of my objects will share a $title and $description. However, the Ad object will have a $price and the Event object will have $startDate. Should I have two separate classes, one for each object? Should I have a 'superclass' with the $title and $description with two other Ad and Event classes with their own properties? The latter is at least the direction I am on now. My second question about this design is how to handle the logic that extracts the data for $title, $description, $price, and $date. For each website in my predefined list, there is a specific regex that returns the desired value for each property. Currently, I have an extremely large switch statement in my constructor which determines what website I am own, sets the regex variables accordingly, and continues on. Not only that, but now I have to repeat the logic to determine what site I am on in the constructor of each class. This doesn't feel right. Should I create another class Algorithms and store the logic there for each site? Should the functions of to handle that logic be in this class? or specific to the classes whos properties they set? I want to take into account in my design two things: 1) I will add different content objects in the future that share $title and $description, but will have their own properties, so, I want to be able to easily grow these as needed. 2) I will add more websites constantly (each with their own algorithms for data extraction) so I would like to plan efficienty managing and working with these now. I thought about extending the Ad or Event class with 'websiteX' class and store its functions there. But, this didn't feel right either as now I have to manage 100s of little website specific class files. Note, I didn't know if this was the correct site or stackoverflow was the better choice. If so, let me know and I'll post there.

    Read the article

  • C# 5: At last, async without the pain

    - by Alex.Davies
    For me, the best feature in Visual Studio 11 is the async and await keywords that come with C# 5. I am a big fan of asynchronous programming: it frees up resources, in particular the thread that a piece of code needs to run in. That lets that thread run something else, while waiting for your long-running operation to complete. That's really important if that thread is the UI thread, or if it's holding a lock because it accesses some data structure. Before C# 5, I think I was about the only person in the world who really cared about asynchronous programming. The trouble was that you had to go to extreme lengths to make code asynchronous. I would forever be writing methods that, instead of returning a value, accepted an extra argument that is a "continuation". Then, when calling the method, I'd have to pass a lambda in to it, which contained all the stuff that needed to happen after the method finished. Here is a real snippet of code that is in .NET Demon: m_BuildControl.FilterEnabledForBuilding(     projects,     enabledProjects = m_OutOfDateProjectFinder.FilterNeedsBuilding(         enabledProjects,         newDirtyProjects =         {             // Mark any currently broken projects as dirty             newDirtyProjects.UnionWith(m_BrokenProjects);             // Copy what we found into the set of dirty things             m_DirtyProjects = newDirtyProjects;             RunSomeBuilds();         })); It's just obtuse. Who puts a lambda inside a lambda like that? Well, me obviously. But surely enabledProjects should just be the return value of FilterEnabledForBuilding? And newDirtyProjects should just be the return value of FilterNeedsBuilding? C# 5 async/await lets you write asynchronous code without it looking so stupid. Here's what I plan to change that code to, once we upgrade to VS 11: var enabledProjects = await m_BuildControl.FilterEnabledForBuilding(projects); var newDirtyProjects = await m_OutOfDateProjectFinder.FilterNeedsBuilding(enabledProjects); // Mark any currently broken projects as dirty newDirtyProjects.UnionWith(m_BrokenProjects); // Copy what we found into the set of dirty things m_DirtyProjects = newDirtyProjects; RunSomeBuilds(); Much easier to read! But how is this the same code? If we were on the UI thread, doesn't the UI thread have to block while FilterEnabledForBuilding runs? No, it doesn't, and that's the magic of the await keyword! It cuts your method up into its constituent pieces, much like I did manually with lambdas before. When you run it, only the piece up to the first await actually runs. The rest is passed to FilterEnabledForBuilding as a continuation, which will get called back whenever that method is finished. In the meantime, our thread returns, and can go back to making the UI responsive, or whatever else threads do in their spare time. This is actually a massive simplification, and if you're interested in all the gory details, and speed hacks that the await keyword actually does for you, I recommend Jon Skeet's blog posts about it.

    Read the article

  • Oracle Partner Architects Training

    - by mseika
    Dear Oracle Partner, There is a lot more to Oracle technology than meets the eye. Sure, you already belong to a small circle of our most experienced and committed partners. But are you making the best use possible of our technology solutions? Put it to the test.  Join the “Oracle Partner Architects Training”. It is aimed at providing your experts, architects and consultants with in-depth architectural knowledge about Oracle technology. Here is your chance to learn from the best. Seasoned speakers, exclusive content and no product marketing. Oracle technology beyond the obvious. Choose from any of the 40 recorded training sessions. Topics include:  • Security• Service integration • Database and options• Data integration • BI and applications• Applications and infrastructure• Hardware and software combinations The market and Oracle value specialized partners More information about specialization can be found on opn.oracle.com. Click through to OPN Program/Specialize “What’s in it for us?” Quite simply: the opportunity to gain the differentiation and competitive edge you need to stand out in the marketplace. • Differentiate your company through expertise in leading Oracle IT solutions;• Get your experts, architects and consultants up to speed on specialized services and solutions;• Make our customers’ shortlists. They are looking for value-added solutions for their business.   Recordings All sessions are recorded. After registering for a session in oraevents, you will receive the info to access the webex recording. Your timing, your tempo.  Registration and more information Visit architects.oraevents.eu to sign up for the recorded sessions. NOTE: Looking to get your consultants Oracle certified? One more reason to join the Oracle Partner Architects Training. It is the fast track to getting their expertise validated with an Oracle certificate. Training schedule  Choose from any of the 40 recorded training sessions: SECURITY THE PRACTICAL APPROACH •  Identity governance• Access management• Data privacy and protection• End-to-end security, layers of exposures•  Identity & access management, why and where to start?• Data security, how? SERVICE INTEGRATION A NEW ROADTO ENTERPRISE-WIDE SERVICE INTEGRATION • Oracle RUEI: maximize business value by insight into real end-user experiences•  Governance challenges in the services landscape•  Creating an agile enterprise (by Jeff Davies)• Oracle’s approach to SOA (by Jeff Davies) - guiding and accelerating SOA success• Technical case study – the SOA challenge• Oracle’s unified business process management suite 11g (incl. demo) DATABASE DATABASE AND OPTIONS, GOINGWIDE •  Understanding service level agreements for databases• Database lifecycle management• Data centric information lifecycle management DATA INTEGRATION  DIS FOR ARCHITECTS • Data integration solutions: an overview• ODI and goldengate• Data quality

    Read the article

  • Move Data into the Grid for Scalable, Predictable Response Times

    - by JuergenKress
    CloudTran is pleased to introduce the availability of the CloudTran Transaction and Persistence Manager for creating scalable, reliable data services on the Oracle Coherence In-Memory Data Grid (IMDG). Use of IMDG architectures has been key to handling today’s web-scale loads because it eliminates database latency by storing important and frequently access data in memory instead of on disk. The CloudTran product lets developers easily use an IMDG for full ACID-compliant transactions without having to be concerned about the location or spread of data. The system has its own implementation of fast, scalable distributed transactions that does NOT depend on XA protocols but still guarantees all ACID properties. Plus, CloudTran asynchronously replicates data going into the IMDG to back-end datastores and back-up data centers, again ensuring ACID properties. CloudTran can be accessed through Java Persistence API (JPA via TopLink Grid) and now, through a new Low-Level API, or LLAPI. This is ideal for use in SOA applications that need data reliability, high availability, performance, and scalability. Still in limited beta release, the LLAPI gives developers the ability to use standard put/remove logic available in Coherence and then wrap logic with simple Spring annotations or XML+AspectJ to start transactions. An important feature of LLAPI is the ability to join transactions. This is a common outcome for SOA applications that need to reduce network traffic by aggregating data into single cache entries and then doing SOA service processing in the node holding the data. This results in the need to orchestrate transaction processing across multiple service calls. CloudTran has the capability to handle these “multi-client” transactions at speed with no loss in ACID properties. Developing software around an IMDG like Oracle Coherence is an important choice for today’s web-scale applications and services. But this introduces new architectural considerations to maintain scalability in light of increased network loads and data movement. Without using CloudTran, developers are faced with an incredibly difficult task to ensure data reliability, availability, performance, and scalability when working with an IMDG. Working with highly distributed data that is entirely volatile while stored in memory presents numerous edge cases where failures can result in data loss. The CloudTran product takes care of all of this, leaving developers with the confidence and peace of mind that all data is processed correctly. For those interested in evaluating the CloudTran product and IMDGs, take a look at this link for more information: http://www.CloudTran.com/downloadAPI.php, or, send your questions to [email protected]. WebLogic Partner Community For regular information become a member in the WebLogic Partner Community please visit: http://www.oracle.com/partners/goto/wls-emea ( OPN account required). If you need support with your account please contact the Oracle Partner Business Center. BlogTwitterLinkedInMixForumWiki Technorati Tags: Coherence,cloudtran,cache,WebLogic Community,Oracle,OPN,Jürgen Kress

    Read the article

  • Why wifi doesn't work in this case?

    - by xRobot
    I have a brand new notebook where I have installed Windows 7 and Ubuntu 12.04 LTS 64bit in dual boot. In windows 7 wifi works but in Ubuntu not. Could you help me please ? iwconfig lo no wireless extensions. wlan0 IEEE 802.11bgn ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=20 dBm Retry long limit:7 RTS thr:off Fragment thr:off Encryption key:off Power Management:off eth0 no wireless extensions. lshw -C network *-network description: Ethernet interface product: RTL8111/8168B PCI Express Gigabit Ethernet controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:01:00.0 logical name: eth0 version: 07 serial: b4:b5:1f:1b:9a:56 size: 10Mbit/s capacity: 1Gbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl8168e-3_0.0.4 03/27/12 latency=0 link=no multicast=yes port=MII speed=10Mbit/s resources: irq:41 ioport:3000(size=256) memory:c2404000-c2404fff memory:c2400000-c2403fff *-network description: Wireless interface product: Ralink corp. vendor: Ralink corp. physical id: 0 bus info: pci@0000:02:00.0 logical name: wlan0 version: 00 serial: 84:4b:f4:0a:3a:22 width: 32 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=rt2800pci driverversion=3.2.0-31-generic firmware=0.34 latency=0 link=no multicast=yes wireless=IEEE 802.11bgn resources: irq:18 memory:c2500000-c250ffff lspci | grep -i net 01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 07) 02:00.0 Network controller: Ralink corp. Device 539a iwlist scan lo Interface doesn't support scanning. wlan0 Interface doesn't support scanning : Device or resource busy eth0 Interface doesn't support scanning. lsmod Module Size Used by rfcomm 47604 0 bnep 18281 2 bluetooth 180104 10 rfcomm,bnep parport_pc 32866 0 ppdev 17113 0 snd_hda_codec_hdmi 32474 1 snd_hda_codec_realtek 224173 1 joydev 17693 0 hp_wmi 18092 0 sparse_keymap 13890 1 hp_wmi snd_hda_intel 33773 3 snd_hda_codec 127706 3 snd_hda_codec_hdmi,snd_hda_codec_realtek,snd_hda_intel snd_hwdep 13668 1 snd_hda_codec snd_pcm 97188 3 snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec snd_seq_midi 13324 0 snd_rawmidi 30748 1 snd_seq_midi snd_seq_midi_event 14899 1 snd_seq_midi snd_seq 61896 2 snd_seq_midi,snd_seq_midi_event snd_timer 29990 2 snd_pcm,snd_seq snd_seq_device 14540 3 snd_seq_midi,snd_rawmidi,snd_seq psmouse 97362 0 snd 78855 16 snd_hda_codec_hdmi,snd_hda_codec_realtek,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device arc4 12529 2 rt2800pci 18715 0 rt2800lib 58925 1 rt2800pci crc_ccitt 12667 1 rt2800lib rt2x00pci 14577 1 rt2800pci rt2x00lib 51144 3 rt2800pci,rt2800lib,rt2x00pci mac80211 506816 3 rt2800lib,rt2x00pci,rt2x00lib soundcore 15091 1 snd mac_hid 13253 0 uvcvideo 72627 0 videodev 98259 1 uvcvideo v4l2_compat_ioctl32 17128 1 videodev wmi 19256 1 hp_wmi i915 473240 3 cfg80211 205544 2 rt2x00lib,mac80211 eeprom_93cx6 12725 1 rt2800pci drm_kms_helper 46978 1 i915 drm 242038 4 i915,drm_kms_helper i2c_algo_bit 13423 1 i915 snd_page_alloc 18529 2 snd_hda_intel,snd_pcm mei 41616 0 serio_raw 13211 0 video 19596 1 i915 lp 17799 0 parport 46562 3 parport_pc,ppdev,lp usbhid 47199 0 hid 99559 1 usbhid r8169 62099 0 rfkill list: # rfkill list 0: phy0: Wireless LAN Soft blocked: no Hard blocked: no 1: hp-wifi: Wireless LAN Soft blocked: no Hard blocked: no

    Read the article

  • Best Frameworks/libraries/engines for 2D multiplayer C# Webbased RPG

    - by Thirlan
    Title is a mouthful but important because I'm looking to meet a specific criteria and it's complex enough that I need a lot of help in finding what I'm looking for. I really want people's suggestions because I trust it a lot more than anything else, so I just need to clearly define what it is I want heh : P Game is a 2D RPG. Think of Secret of Mana. Game is online multiplayer, but not MMO sized. Game must be webbased! I'm looking to the future and want to hit as many platforms as possible. I'm leaning to Webgl because of this, but still looking around. Since the users are seeing the game through the webbrowser the front-end should be mainly responsible for drawing, taking input and some basic checking such as preliminary collision detection. This is important because it means the game engine is NOT on the client's machine. The server should be responsible for the game engine and all the calculations. This means the server is doing all the work and the client is mostly a dumb terminal. Server language is c# I'm looking for fast project execution so I want to use as many pre-existing tools as possible. This would make sense because I'm making a game here, not an engine. I'm not creating some new revolutionary graphics or pushing the physics engines to the next level. Preference for commercially supported tools. For game mechanics reasons and for reasons 4 and 5, don't think I can use existing 2D rpg engines. I've seen them out there and I fear that if I try and use them they will have too many restrictions, but will be happy to hear out suggestions. So all this means I need a game engine on the server, or maybe just a physics engine, and then I need another engine/library to draw everything that the server is sending to the client on the webbrowser. Maybe this is how 50% of games work on the web and there are plenty of frameworks that support this! I wouldn't actually don't know : ( but my gut is telling me that most webgames are single player and 90% of the game is running on the client. So... any suggestions?

    Read the article

  • Collision in PyGame for spinning rectangular object.touching circles

    - by OverAchiever
    I'm creating a variation of Pong. One of the differences is that I use a rectangular structure as the object which is being bounced around, and I use circles as paddles. So far, all the collision handling I've worked with was using simple math (I wasn't using the collision "feature" in PyGame). The game is contained within a 2-dimensional continuous space. The idea is that the rectangular structure will spin at different speed depending on how far from the center you touch it with the circle. Also, any extremity of the rectangular structure should be able to touch any extremity of the circle. So I need to keep track of where it has been touched on both the circle and the rectangle to figure out the direction it will be bounced to. I intend to have basically 8 possible directions (Up, down, left, right and the half points between each one of those). I can work out the calculation of how the objected will be dislocated once I get the direction it will be dislocated to based on where it has been touch. I also need to keep track of where it has been touched to decide if the rectangular structure will spin clockwise or counter-clockwise after it collided. Before I started coding, I read the resources available at the PyGame website on the collision class they have (And its respective functions). I tried to work out the logic of what I was trying to achieve based on those resources and how the game will function. The only thing I could figure out that I could do was to make each one of these objects as a group of rectangular objects, and depending on which rectangle was touched the other would behave accordingly and give the illusion it is a single object. However, not only I don't know if this will work, but I also don't know if it is gonna look convincing based on how PyGame redraws the objects. Is there a way I can use PyGame to handle these collision detections by still having a single object? Can I figure out the point of collision on both objects using functions within PyGame precisely enough to achieve what I'm looking for? P.s: I hope the question was specific and clear enough. I apologize if there were any grammar mistakes, English is not my native language.

    Read the article

  • Using elapsed time for SlowMo in XNA

    - by Dave Voyles
    I'm trying to create a slow-mo effect in my pong game so that when a player is a button the paddles and ball will suddenly move at a far slower speed. I believe my understanding of the concepts of adjusting the timing in XNA are done, but I'm not sure of how to incorporate it into my design exactly. The updates for my bats (paddles) are done in my Bat.cs class: /// Controls the bat moving up the screen /// </summary> public void MoveUp() { SetPosition(Position + new Vector2(0, -moveSpeed)); } /// <summary> /// Controls the bat moving down the screen /// </summary> public void MoveDown() { SetPosition(Position + new Vector2(0, moveSpeed)); } /// <summary> /// Updates the position of the AI bat, in order to track the ball /// </summary> /// <param name="ball"></param> public virtual void UpdatePosition(Ball ball) { size.X = (int)Position.X; size.Y = (int)Position.Y; } While the rest of my game updates are done in my GameplayScreen.cs class (I'm using the XNA game state management sample) Class GameplayScreen { ........... bool slow; .......... public override void Update(GameTime gameTime, bool otherScreenHasFocus, bool coveredByOtherScreen) base.Update(gameTime, otherScreenHasFocus, false); if (IsActive) { // SlowMo Stuff Elapsed = (float)gameTime.ElapsedGameTime.TotalSeconds; if (Slowmo) Elapsed *= .8f; MoveTimer += Elapsed; double elapsedTime = gameTime.ElapsedGameTime.TotalMilliseconds; if (Keyboard.GetState().IsKeyDown(Keys.Up)) slow = true; else if (Keyboard.GetState().IsKeyDown(Keys.Down)) slow = false; if (slow == true) elapsedTime *= .1f; // Updating bat position leftBat.UpdatePosition(ball); rightBat.UpdatePosition(ball); // Updating the ball position ball.UpdatePosition(); and finally my fixed time step is declared in the constructor of my Game1.cs Class: /// <summary> /// The main game constructor. /// </summary> public Game1() { IsFixedTimeStep = slow = false; } So my question is: Where do I place the MoveTimer or elapsedTime, so that my bat will slow down accordingly?

    Read the article

  • More on Map Testing

    - by Michael Stephenson
    I have been chatting with Maurice den Heijer recently about his codeplex project for the BizTalk Map Testing Framework (http://mtf.codeplex.com/). Some of you may remember the article I did for BizTalk 2009 and 2006 about how to test maps but with Maurice's project he is effectively looking at how to improve productivity and quality by building some useful testing features within the framework to simplify the process of testing maps. As part of our discussion we realized that we both had slightly different approaches to how we validate the output from the map. Put simple Maurice does some xpath validation of the data in various nodes where as my approach for most standard cases is to use serialization to allow you to validate the output using normal MSTest assertions. I'm not really going to go into the pro's and con's of each approach because I think there is a place for both and also I'm sure others have various approaches which work too. What would be great is for the map testing framework to provide support for different ways of testing which can cover everything from simple cases to some very specialized scenarios. So as agreed with Maurice I have done the sample which I will talk about in the rest of this article to show how we can use the serialization approach to create and compare the input and output from a map in normal development testing. Prerequisites One of the common patterns I usually implement when developing BizTalk solutions is to use xsd.exe to create .net classes for most of the schemas used within the solution. In the testing pattern I will take advantage of these .net classes. The Map In this sample the map we will use is very simple and just concatenates some data from the input message to the output message. Hopefully the below picture illustrates this well. The Test In the test I'm basically taking the following actions: Use the .net class generated from the schema to create an input message for the map Serialize the input object to a file Run the map from .net using the standard BizTalk test method which was generated for running the map Deserialize the output file from the map execution to a .net class representing the output schema Use MsTest assertions to validate things about the output message The below picture shows this: As you can see the code for this is pretty simple and it's all strongly typed which means changes to my schema which can affect the tests can be easily picked up as compilation errors. I can then chose to have one test which validates most of the output from the map, or to have many specific tests covering individual scenarios within the map. Summary Hopefully this post illustrates a powerful yet simple way of effectively testing many BizTalk mapping scenarios. I will probably have more conversations with Maurice about these approaches and perhaps some of the above will be included in the mapping test framework.   The sample can be downloaded from here: http://cid-983a58358c675769.office.live.com/self.aspx/Blog%20Samples/More%20Map%20Testing/MapTestSample.zip

    Read the article

  • Setting up Ubuntu on my mother's computer

    - by idealmachine
    Intended use My mother had an old Compaq desktop computer running Windows 98, which she used for occasional Web browsing and playing cards. The name of her card game is Hoyle Card Games 3. Although I had to repair it several times over the last 10 years, it worked fine until it finally died at the end of last year. Hardware specifications A relative brought up a newer computer soon afterward: Operating system: Windows XP Asus K8N motherboard (with broken on-board sound; getting a sound card) Athlon 64? processor (don't remember the clock speed) 512 MB RAM Hope the graphics card works... Replacement sound card will be one of: Ensoniq ES1370 AudioPCI Diamond Monster Sound MX300 (Aureal chipset) Sound Blaster Audigy 2 SE Peripherals HP Scanjet 3400c scanner (USB connected) HP LaserJet multi-function printer (parallel port connected, and printing works with a PCL driver) Same serial mouse as old computer Question I had set up an SSH/VNC connection to allow for remotely working out problems. Or so I thought. A month later, the computer would not boot, rendering the SSH connection useless and an OS reinstall necessary. Unfortunately, I have neither the original Windows disc nor the product key. Unless I were to pay $200 for a full Windows 7 Home Premium license for my computer, I would not be able to re-install Windows XP on hers. I consider myself an advanced Linux user, having used Debian for years. So here are my questions. I have only one day to decide whether to use Ubuntu or buy Windows: A quick search leads me to believe all the hardware listed above is supposed to work with Linux, but am I mistaken? Would Ubuntu/Xubuntu suffice (specify which one if it matters), or would I be better off paying the $200 necessary for Windows XP? Is the card game likely to run on Wine? I believe the minimum system requirement is Windows 95. Failing Wine compatibility, will VirtualBox run fast enough on such a computer (Windows 98 as the guest OS)? Are there any free card games just as good? She plays mainly Bridge, Poker, and Solitaire. Is there any "Large Fonts" option for those with poor vision? The lack of it would be a big disadvantage. BONUS: Although I would probably replace the old mouse upon a move to Ubuntu, is it even possible to get a serial mouse working?

    Read the article

  • What are these errors when I try to "make" the driver of my wireless network?

    - by Tom Brito
    I got got a wireless to usb adapter, and I'm having some trouble to install the drivers on Ubuntu. First of all, the readme file say to use the "make" command, and I already got errors: $ make make[1]: Entering directory `/usr/src/linux-headers-2.6.35-22-generic' CC [M] /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.o /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c: In function ‘rtl8192_usb_probe’: /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12325: error: ‘struct net_device’ has no member named ‘open’ /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12326: error: ‘struct net_device’ has no member named ‘stop’ /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12327: error: ‘struct net_device’ has no member named ‘tx_timeout’ /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12328: error: ‘struct net_device’ has no member named ‘do_ioctl’ /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12329: error: ‘struct net_device’ has no member named ‘set_multicast_list’ /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12330: error: ‘struct net_device’ has no member named ‘set_mac_address’ /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12331: error: ‘struct net_device’ has no member named ‘get_stats’ /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.c:12332: error: ‘struct net_device’ has no member named ‘hard_start_xmit’ make[2]: *** [/home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u/r8192U_core.o] Error 1 make[1]: *** [_module_/home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/HAL/rtl8192u] Error 2 make[1]: Leaving directory `/usr/src/linux-headers-2.6.35-22-generic' make: *** [all] Error 2 /home/wellington/Desktop/rtl8192su_linux_2.4_2.6.0003.0301.2010/ is the path where I copied the drivers on my computer. Any idea how to solve this? (I don't even know what the error is...) update: sudo lshw -class network *-network description: Ethernet interface product: RTL8111/8168B PCI Express Gigabit Ethernet controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:01:00.0 logical name: eth0 version: 03 serial: 78:e3:b5:e7:5f:6e size: 10MB/s capacity: 1GB/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix vpd bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half latency=0 link=no multicast=yes port=MII speed=10MB/s resources: irq:42 ioport:d800(size=256) memory:fbeff000-fbefffff memory:faffc000-faffffff memory:fbec0000-fbedffff *-network DISABLED description: Wireless interface physical id: 2 logical name: wlan0 serial: 00:26:18:a1:ae:64 capabilities: ethernet physical wireless configuration: broadcast=yes multicast=yes wireless=802.11b/g

    Read the article

  • Understanding exceptional cases

    - by Justin
    I've been studying the use of exceptions in various php projects (such as Doctrine and Zend Framework). Exceptions seem to be thrown when unordinary input/state occurs. A perfect example is Doctrine throwing an exception when you try to use a invalid query string. I think the creators of the doctrine api understood that first, you can't query data by using an invalid DQL statement, and a developer should immediately be warned that an error has occurred, rather then letting execution continue with the possibility of an error code going un-checked. I also bet that this simplifies reading the code. I can't think of a situation where you would want to use an invalid DQL statement, except unit testing. Since this is true, it's better to avoid plaguing a bunch of code with null/error checks and use exceptions. I've read in books that exceptions shouldn't be thrown when validating dating user input. I've seen examples where of where the guideline is broken. One example is the Zend framework. If supplying an invalid controller or action name, an exception is thrown. Unlike doctrine, the user has more direct control over this sort of input. I know you can configure an error controller and set up a 404 message or what have you, but I'm curious why they have used an exception in this scenario? I guess you can argue the Zend Framework does not know how to continue processing the quest. One last example Is I wrote a function to return some html based on a given resource type. This resource type is hard-coded and sent when a user interacts with a web site (such as clicking a button to display the form to input data). I don't expect users to be mucking around with the request type. Under normal operating conditions, the resource type should be valid. To clean up some logic, I was going to throw an exception if a particular form wasn't found. This is mainly to find the correct form associated with a resource type so proper validation can occur. Does this sound like a valid use case for an exception? Right now it's pretty trivial, but I do plan to implement a restful consumer and re-using a function to map resources to their validation services would be very useful. I can then catch the exception and based on the consumer, return an error message suitable for the request type...

    Read the article

  • external USB HD doesn't show up on 'sudo fdisk -l' on one Ubuntu, shows up on another (both 'precise')

    - by Menelaos
    I have a 1.5TB WD external USB HDD and two Ubuntu systems, both 'precise'. When I plug the disk on system A it doesn't show up on the output of sudo fdisk -l nor is it automatically mounted (note that that wasn't always the case - it used to appear in the past). When I plug it on system B (again Ubuntu precise) it shows up when I do a sudo fdisk -l (output appended at the end) and mounts automatically just fine. What does this discrepancy point to and what kind of diagnostics should I run / tools I should use to troubleshoot the problem? I followed the suggestion I received to do a sudo tail -f /var/log/syslog and the output is the following when I plug, unplug and replug the USB cable on System A: Sep 14 23:27:09 thorin mtp-probe: checking bus 2, device 3: "/sys/devices/pci0000:00/0000:00:13.2/usb2/2-2" Sep 14 23:27:09 thorin mtp-probe: bus: 2, device: 3 was not an MTP device Sep 14 23:28:01 thorin kernel: [ 338.994295] usb 2-2: USB disconnect, device number 3 Sep 14 23:28:04 thorin kernel: [ 341.808139] usb 2-2: new high-speed USB device number 4 using ehci_hcd Sep 14 23:28:04 thorin mtp-probe: checking bus 2, device 4: "/sys/devices/pci0000:00/0000:00:13.2/usb2/2-2" Sep 14 23:28:04 thorin mtp-probe: bus: 2, device: 4 was not an MTP device Sep 14 23:29:54 thorin AptDaemon: INFO: Quitting due to inactivity Sep 14 23:29:54 thorin AptDaemon: INFO: Quitting was requested (I guess the last two message are irrelevant). Output of sudo fdisk -l on System B $ sudo fdisk -l Disk /dev/sda: 1500.3 GB, 1500301910016 bytes 255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00070db4 Device Boot Start End Blocks Id System /dev/sda1 * 2048 2905114623 1452556288 83 Linux /dev/sda2 2905116670 2930276351 12579841 5 Extended /dev/sda5 2905116672 2930276351 12579840 82 Linux swap / Solaris Disk /dev/sdb: 250.1 GB, 250059350016 bytes 255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x9c849c84 Device Boot Start End Blocks Id System /dev/sdb1 * 63 488375999 244187968+ 7 HPFS/NTFS/exFAT Disk /dev/sdg: 1500.3 GB, 1500299395072 bytes 255 heads, 63 sectors/track, 182401 cylinders, total 2930272256 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x0003e17f Device Boot Start End Blocks Id System /dev/sdg1 2048 2930272255 1465135104 7 HPFS/NTFS/exFAT

    Read the article

< Previous Page | 287 288 289 290 291 292 293 294 295 296 297 298  | Next Page >