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• Developing wheel reinventing tendencies into a skill as opposed to reluctantly learning wheel-finding skills? [duplicate]

  - by Korey Hinton

  This question already has an answer here: Is reinventing the wheel really all that bad? 20 answers I am more of a high-level wheel reinventor. I definitely prefer to make use of existing API features built into a language and popular third-party frameworks that I know can solve the problem, however when I have a particular problem that I feel capable of solving within a reasonable time I am very reluctant to find someone else's solution. Here are a few reasons why I reinvent: It takes time to learn a new API API restrictions might exist that I don't know about Avoiding re-work of unfamiliar code I am conflicted between doing what I know and shifting to a new technique I don't feel comfortable with. On one hand I feel like following my instincts and getting really good at solving problems, especially ones that I would never challenge myself with if all I did was try to find answers. And on the other hand I feel like I might be missing out on important skills like saving time by finding the right framework and expanding my knowledge by learning how to use a new framework. I guess my question comes down to this: My current attitude is to stick to the built-in API and APIs I know well* and to not spend my time searching github for a solution to a problem I know I can solve myself within a reasonable amount of time. Is that a reasonable balance for a successful programmer? *Obviously I will still look around for new frameworks that save time and solve/simplify difficult problems.

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• Handling exceptions raised in observers

  - by sparky

  I have a Rails (2.3.5) application where there are many groups, and each Group has_many People. I have a Group edit form where users can create new people. When a new person is created, they are sent an email (the email address is user entered on the form). This is accomplished with an observer on the Person model. The problem comes when ActionMailer throws an exception - for example if the domain does not exist. Clearly that cannot be weeded out with a validation. There would seem to be 2 ways to deal with this: A begin...rescue...end block in the observer around the mailer. The problem with this is that the only way to pass any feedback to the user would be to set a global variable - as the observer is out of the MVC flow, I can't even set a flash[:error] there. A rescue_from in the Groups controller. This works fine, but has 2 problems. Firstly, there is no way to know which person threw the exception (all I can get is the 503 exception, no way to know which person caused the problem). This would be useful information to be able to pass back to the user - at the moment, there is no way for me to let them know which email address is the problem - at the moment, I just have to chuck the lot back at them, and issue an unhelpful message saying that one of them is not correct. Secondly (and to a certain extent this make the first point moot) it seems that it is necessary to call a render in the rescue_from, or it dies with a rather bizarre "can't convert Array into String" error from webbrick, with no stack trace & nothing in the log. Thus, I have to throw it back to the user when I come across the first error and have to stop processing the rest of the emails. Neither of the solutions are optimal. It would seem that the only way to get Rails to do what I want is option 1, and loathsome global variables. This would also rely on Rails being single threaded. Can anyone suggest a better solution to this problem?

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• Is StackOverflow making me stupid? [closed]

  - by Ayush Goyal

  Possible Duplicate: When stuck, how quickly should one resort to Stack Overflow? Its good that solution to almost every programming problem is available at my disposal, either someone has asked it before or programming gurus are waiting for me to post it..sometimes its just the matter of seconds after posting the question and someone points out the error-causing-line or proposes alternate (easier, lightweight and efficient) solution. But today it struck me "is this making me dumb?" In good (umm..not so good) old days I used to figure out the source of my problem and then work it out myself, though it used to eat up lot of time but it helped in developing my logical thinking as it used to make an impression in my mind due to which I tend to avoid that situation in future codes. Now, as soon as I encounter a problem I just give it a shot or two and head towards the community. Many times after looking at the solution it turns out that answer was all in front of me..all I needed was to take a break, hover it once and its solved. Both the approaches make me feel guilty, for wasting time when I could have asked and solved it within minutes OR being too lazy to look over it again before posting the code snippet.

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• Does unit testing lead to premature generalization (specifically in the context of C++)?

  - by Martin

  Preliminary notes I'll not go into the distinction of the different kinds of test there are, there are already a few questions on these sites regarding that. I'll take what's there and that says: unit testing in the sense of "testing the smallest isolatable unit of an application" from which this question actually derives The isolation problem What is the smallest isolatable unit of a program. Well, as I see it, it (highly?) depends on what language you are coding in. Micheal Feathers talks about the concept of a seam: [WEwLC, p31] A seam is a place where you can alter behavior in your program without editing in that place. And without going into the details, I understand a seam -- in the context of unit testing -- to be a place in a program where your "test" can interface with your "unit". Examples Unit test -- especially in C++ -- require from the code under test to add more seams that would be strictly called for for a given problem. Example: Adding a virtual interface where non-virtual implementation would have been sufficient Splitting -- generalizing(?) -- a (smallish) class further "just" to facilitate adding a test. Splitting a single-executable project into seemingly "independent" libs, "just" to facilitate compiling them independently for the tests. The question I'll try a few versions that hopefully ask about the same point: Is the way that Unit Tests require one to structure an application's code "only" beneficial for the unit tests or is it actually beneficial to the applications structure. Is the generalization code need to exhibit to be unit-testable useful for anything but the unit tests? Does adding unit tests force one to generalize unnecessarily? Is the shape unit tests force on code "always" also a good shape for the code in general as seen from the problem domain? I remember a rule of thumb that said don't generalize until you need to / until there's a second place that uses the code. With Unit Tests, there's always a second place that uses the code -- namely the unit test. So is this reason enough to generalize?

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• recent unreliable wireless connection with Netgear KWGR614 router

  - by gabkdlly

  Recently, my internet connection over wireless ( via a Netgear KWGR614 router ) has become unreliable, on both a Dell laptop running Ubuntu 10.04 as well as my Desktop running Ubuntu 10.10 . The problem does not seem to occur on a laptop running Windows Vista, nor on a Desktop running Windows 7 ( this machine is connected with an ethernet cable ). The problem does not seem to occur on my Openmoko Freerunner ( running Android 1.5 ), though I hardly ever use this device to connect over WLAN, so the problem may have just slipped by. On my main Ubuntu Desktop, I have tried the following wireless devices: a Longshine PCI card ( an old device with an RTL8180L chip ) a D-Link DWL-510 PCI card ( this device threw warnings in dmesg ) a USB device from MSI ( US54EX ). Usually my wireless network shows up in the network manager with a normal signal strength, even when the connection speed is slow or the connection gets reset ( asking me to click connect to re-authenticate my wireless connection ). I know that this router is susceptible to denial of service attacks, as I have previously been able to disrupt its operation by putting an nmap scan into a while loop. Is it possible that someone is jamming my signal ?

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• Trying to compile from source newest apache with newest openssl

  - by AlexMA

  I need to install apache 2.4.10 using openssl 1.0.1i. I compiled openssl from source with: $ ./config \ --prefix=/opt/openssl-1.0.1i \ --openssldir=/opt/openssl-1.0.1i $ make $ sudo make install and Apache with: ./configure --prefix=/etc/apache2 \ --enable-access_compat=shared \ --enable-actions=shared \ --enable-alias=shared \ --enable-allowmethods=shared \ --enable-auth_basic=shared \ --enable-authn_core=shared \ --enable-authn_file=shared \ --enable-authz_core=shared \ --enable-authz_groupfile=shared \ --enable-authz_host=shared \ --enable-authz_user=shared \ --enable-autoindex=shared \ --enable-dir=shared \ --enable-env=shared \ --enable-headers=shared \ --enable-include=shared \ --enable-log_config=shared \ --enable-mime=shared \ --enable-negotiation=shared \ --enable-proxy=shared \ --enable-proxy_http=shared \ --enable-rewrite=shared \ --enable-setenvif=shared \ --enable-ssl=shared \ --enable-unixd=shared \ --enable-ssl \ --with-ssl=/opt/openssl-1.0.1i \ --enable-ssl-staticlib-deps \ --enable-mods-static=ssl make (would run sudo make install next but I get an error) I'm essentially following the guide here except with newer slightly newer versions. My problem is I get a linker error when I run make for apache: Making all in support make[1]: Entering directory `/home/developer/downloads/httpd-2.4.10/support' make[2]: Entering directory `/home/developer/downloads/httpd-2.4.10/support' /usr/share/apr-1.0/build/libtool --silent --mode=link x86_64-linux-gnu-gcc -std=gnu99 -pthread -L/opt/openssl-1.0.1i/lib -lssl -lcrypto \ -o ab ab.lo /usr/lib/x86_64-linux-gnu/libaprutil-1.la /usr/lib/x86_64-linux-gnu/libapr-1.la -lm /usr/bin/ld: /opt/openssl-1.0.1i/lib/libcrypto.a(dso_dlfcn.o): undefined reference to symbol 'dlclose@@GLIBC_2.2.5' I tried the answer here, but no luck. I would prefer to just use aptitude, but unfortunately the versions I need aren't available yet. If anyone knows how to fix the linker problem (or what I think is a linker problem), or knows of a better way to tell apache to use a newer openssl, it would be greatly appreciated; I've got apache 1.0.1i working otherwise.

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• Black screen with thinkpad edge e525, AMD radeon HD before and after installation, plymouth?

  - by carolien

  I have a new thinkpad edge e525 (which should work) and wanted to try ubuntu (first linux experience). With the ubuntu desktop-cd I had a blackscreen before installation, I could fix that with nomodeset. After the installation, when rebooting I got the black screen again. First I see some ubuntu colour with a green busted stripe. I have the same problem with the live boot, also tried mint live, the stripe gets pink. I installed xubuntu 64bit from an alternate cd and I didnt have problems until de reboot after the installation. Same problem, just a black screen with the green stripe than blackscreen. I tried several things: adding nomodeset to the bootmenu, but than I get: No connection to plymouth and it is stuck at checking the battery status. I tried to replace quiet splash with text. Didnt work either. actually one time I saw a blue booting image before that. I managed to get a root command though via the recovery boot. I didnt dare to just remove the plymouth package. Can I just delete plymouth or do I have to deinstall it as described in several ways. (Problem is, right now the notebook doesnt have a internet connection. And I dont know how to manage it with a usb stick?) Or do I have to install the AMD catalyst driver manually? (Again, how can I do that with an usb stick) I also tried this: Ubuntu hits a black screen after boot. Is there any solution without internet? And if I need internet which is the right one? Please explain step by step what I have to write and so on! Thank you! also tried: set gfxpayload=text and: just remove splash and adding vesafb.nonsense=1 to the grub editor, because I couldnt find it anywhere

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• this.BoundingBox.Intersects(Wall[0].BoundingBox) not working properly

  - by Pieter

  I seem to be having this problem a lot, I'm still learning XNA / C# and well, trying to make a classic paddle and ball game. The problem I run into (and after debugging have no answer) is that everytime I run my game and press either of the movement keys, the Paddle won't move. Debugging shows that it never gets to the movement part, but I can't understand why not? Here's my code: // This is the If statement for checking Left movement. if (keyboardState.IsKeyDown(Keys.Left) || keyboardState.IsKeyDown(Keys.A)) { if (!CheckCollision(walls[0])) { Location.X -= Velocity; } } //This is the CheckCollision(Wall wall) boolean public bool CheckCollision(Wall wall) { if (this.BoundingBox.Intersects(wall.BoundingBox)) { return true; } return false; } As far as I can tell there should be absolutely no problem with this, I initialize the bounding box in the constructor whenever a new instance of Walls and Paddle is created. this.BoundingBox = new Rectangle(0, 0, Sprite.Width, Sprite.Height); Any idea as to why this isn't working? I have previously succeeded with using the whole Location.X < Wall.Location.X + Wall.Texture.Width code... But to me that seems like too much coding if a simple boolean check could be done.

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• Choppy USB mice on just one of USB ports

  - by user20532

  I've got Lenovo b560 laptop with latest, properly updated Kubuntu on it (11.04 natty, kernel 2.6.38-8-generic). It has three USB2.0 ports onboard. I usually plug a mouse into one of them (I've got 3 different mice - in office, at home and for when on the go). Sometimes, usually after laptop awakening from sleep, the mouse still works but cursor movements are choppy, as if the processor was extremely loaded (it's usually not). I found that if I re-plug the mouse cord into the other USB port, it works just fine. If I plug it back to problematic port, it is still choppy and remains choppy until next boot. Of course I want my mice to always work fine. Problem is: I cannot reproduce this behavior for sure, it happens sporadically but regularly. I use different USB ports (problem has ever happened on each of them since), I use different mice (each has failed me this way at least once), I cannot generally find what exactly is going wrong and why plugging to different port fixes the mouse instantly. So I'd like to hear at least clues where to look at, what to try to identify my problem. A bit of update: while beginning this post, I had the issue once again. I have just replugged the mouse back to problematic port and it is not recognized at all. On the other port it works smoothly.

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• Pandaboard crash on startup or freeze after minutes

  - by Meach

  I just received my Pandaboard ES (rev B) and I am having trouble after installing ubuntu-omap4-addons. Once I copied the image ubuntu-12.04-preinstalled-desktop-armhf+omap4.img on my sd card and boot the pandaboard with it, I run the following commands: sudo add-apt-repository ppa:tiomap-dev/release sudo apt-get update sudo apt-get dist-upgrade sudo apt-get install ubuntu-omap4-extras At the end of the installation of ubuntu-omap4-extras, Ubuntu tells me that a problem occurs when the console displays: ldconfig deferred processing now taking place Clicking on "report the problem" tell me that the problem concerns pvr-omap4-dkms. I read somewhere that this can happen and it is better to reinstall pvr-omap4-dkms. Which I am doing by running: sudo apt-get install --reinstall pvr-omap4-dkms I reboot. Then the board has sometimes difficulties to start Ubuntu: it freezes during the loading page, only action I can do is unplugging the board to start it again. Some other times, Ubuntu load successfully but then freeze at another random time, in the range 20 - 40 minutes. I searched on internet for similar bug and found this: https://bugs.launchpad.net/ubuntu/+source/linux-ti-omap4/+bug/971091 So I typed this in: update-rc.d ondemand disable apt-get -y install cpufrequtils echo 'ENABLE="true" GOVERNOR="performance" MAX_SPEED="0" MIN_SPEED="0"' > /etc/default/cpufrequtils cpufreq-set -r -g performance reboot But it doesn't seems to fix the bug. Another detail: on startup, before the loading screen of Ubuntu (when there is the two penguins displayed :)), it shows this: [0.297271] CPU1: Unknown IPI message 0x1 [0.308990] omap_hwmod: mcpdm: _wait_target_ready error: -16 [0.354705] omap_mux_get_by_name: Could not find signal uart1_cts.uart1_cts [0.354766] omap_hwmod_mux_init: Could not allocate device mux entry [2.107086] thermal_get_slope:Getting slope is not supported for domain gpu [2.107116] thermal_get_offset:Getting offset is not supported for domain gpu [2.107299] stm_fw: vendor driver stm_ti1.0 registered [8.725555] OMAPRPC: Registration of OMAPRPC rpmsg service returned 0! debug=0 Any idea what can be wrong? I am not that good with Ubuntu so any help will be appreciated. Cheers! Meach

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• How to sell logistical procedures that require less time to perform but more finesse?

  - by foampile

  I am working with a group where part of the responsibilities is managing a certain set of configuration files which, of course, have the same skeleton/structure across different environments but different values (like server, user, this setting, that setting etc.). Pretty classic scenario... The problem is that everyone just goes and modifies final, environment-specific files and basically repeats the work for every environment. Personally, I am offended to have to peform repeatable, mundane tasks in this day and age when we have technologies to automate it all. So I devised a very simple procedure of abstracting the files into templates, stubbing env-specific values with parameters and then wrote a simple Perl script that, given a template and an environment matrix with env-specific values for each param, produces the final file. So this is nothing special, cutting-edge or revolutionary -- I am pretty sure that 20 years ago efficient places did their CM like that. However, that requires that changes are made at the template level and then distributed across different environments using the script and not making changes in the final environment-specific files. This is where I am encountering resentment as they feel "comfortable" doing it their old, manual, repeated labor way. Personally, I don't have a problem with them working hard rather than smart but the problem is when I have to build on top of someone else's changes, I have to merge their changes into my template from a specific file, which takes time and is grueling. So my question is how to go about selling my method, which makes it so much faster in an environment that is resentful to change and where most things have to be done at the level of the least competent team member?

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• Nifty default controls prevent the rest of my game from rendering

  - by zergylord

  I've been trying to add a basic HUD to my 2D LWJGL game using nifty gui, and while I've been successful in rendering panels and static text on top of the game, using the built-in nifty controls (e.g. an editable text field) causes the rest of my game to not render. The strange part is that I don't even have to render the gui control, merely declaring it appears to cause this problem. I'm truly lost here, so even the vaguest glimmer of hope would be appreciated :-) Some code showing the basic layout of the problem: display setup: // load default styles nifty.loadStyleFile("nifty-default-styles.xml"); // load standard controls nifty.loadControlFile("nifty-default-controls.xml"); screen = new ScreenBuilder("start") {{ layer(new LayerBuilder("baseLayer") {{ childLayoutHorizontal(); //next line causes the problem control(new TextFieldBuilder("input","asdf") {{ width("200px"); }}); }}); }}.build(nifty); nifty.gotoScreen("start"); rendering glMatrixMode(GL_PROJECTION); glLoadIdentity(); GLU.gluOrtho2D(0f,WINDOW_DIMENSIONS[0],WINDOW_DIMENSIONS[1],0f); //I can remove the 2 nifty lines, and the game still won't render nifty.render(true); nifty.update(); glMatrixMode(GL_PROJECTION); glLoadIdentity(); GLU.gluOrtho2D(0f,(float)VIEWPORT_DIMENSIONS[0],0f,(float)VIEWPORT_DIMENSIONS[1]); glTranslatef(translation[0],translation[1],0); for (Bubble bubble:bubbles){ bubble.draw(); } for (Wall wall:walls){ wall.draw(); } for(Missile missile:missiles){ missile.draw(); } for(Mob mob:mobs){ mob.draw(); } agent.draw();

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• Dual booted Windows 7 freezes after login screen

  - by Cathal

  First-time Linux user, using a Packard Bell Easy Note TS laptop. My problem arose after I dual boot installed Ubuntu 12.04 on Windows 7 via WUBI. I backed up all my data, and reinstalled Windows from factory settings on the recovery partition. When I first tried to install Ubuntu I mistakenly closed the lid at the start of the installation, stopping it. After that I rebooted, and my second installation attempt went without a hitch. Ubuntu works perfectly, the data on the partitions seem to be fine. My problem is I can't log back in to Windows 7. After selecting it in GRUB, and then in the Windows 7/ WUBI choice on boot, it loads up perfectly til the user log in screen. After the password is inputted, it stalls on the "Welcome" busy screen. This happens in Safe mode as well. Startup repair can't find a problem and neither can CHKDSK. System restore and Last known good config have no effect either. If anyone could help me out, I'd be real grateful. edit in response to the question below, since I don't know how to comment: Windows was installed first and its partitions are the first on the list. Should I move the windows partitions to after the Linux ones on the disk? Thanks for your help.

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• How can I get my monitor's maximum resolution without the proprietary AMD graphic driver installed?

  - by Venki

  I am using Ubuntu 14.04. I have an AMD Radeon 5570 HD graphic card. Actually, the default open source REDWOOD drivers aren't allowing me to choose my monitor's maximum screen resolution(which is 1366 x 768). I just have two resolutions displayed which are 1024x768 and 800x600 . If I give the command : xrandr -s 1366x768 then the output is: Size 1366x768 not found in available modes So just for the sake of getting 1366x768 resolution I am forced to install the proprietary graphic driver that AMD gives me from its site. But if I install it(which itself is quite a problem-prone process), I undergo a lot of 'inconvenience'. Sometimes after an OS update, the driver crashes unity. Then I will have to uninstall that driver from a tty and google around for a solution. Also I encounter screen tearing problems occasionally. In addition I also cant see my login screen(See this question which states this particular problem). The main problem is AMD does not update its driver as quick as Ubuntu updates its OS. This is quite irritating. So, I want the maximum resolution(and performance) that my graphics card and monitor can give me without installing the 'problematic' proprietary graphic card driver that AMD gives. Is this possible? Suggestions please. Thanks in advance. PS :- More system specs details:- Intel i3 2100 processor AMD P8H61-M PLUS2 motherboard AMD Radeon 5570 HD graphic card DELL monitor (BTW, Thank you for reading through my elaborate description!)

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• Source code not matching uploaded HTML file

  - by benhowdle89

  I'm not sure if this is the right place to ask but i'm having a hugely frustrating problem with Coda and my website (i'm not sure which one is causing the issue) I'm using Coda to make changes to my website, Coda uses built in FTP to save changes to your web page. So when you hit Save, it uploads the new file. I've been using Coda for months and never had a problem until now. I am making changes in the html of my index.php and hitting save, it's successfully uploading the file but no changes are reflected in the source code in ANY browser. I even logged into cPanel on my website, ie. www.example.com:2082 and looked at the file - the changes have been made successfully. But the actual webpage in browser's source code, no changes?? I have tried adding which made no difference. Interestingly i make changes to style.css and the changes are instant. I have emptied the cache on all of my browsers but i'm still having an issue. Does this sound like a Coda problem or has anyone heard of such a thing?

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• Sun Java crashing, mostly with jboss

  - by Joel

  I'm on Ubuntu 10.10. I keep having problems with Sun Java crashing on me. I mostly have it crashing on my Jboss server, but I've had it crash MANY MANY times running ANT tasks or the IntelliJ IDE. Here's what it prints: # # A fatal error has been detected by the Java Runtime Environment: # # SIGSEGV (0xb) at pc=0x00007f67e665d440, pid=21260, tid=140082772170512 # # JRE version: 6.0_22-b04 # Java VM: Java HotSpot(TM) 64-Bit Server VM (17.1-b03 mixed mode linux-amd64 ) # Problematic frame: # V [libjvm.so+0x2f2440] # # An error report file with more information is saved as: # /home/blah/blah/blah/hs_err_pid21260.log # # If you would like to submit a bug report, please visit: # http://java.sun.com/webapps/bugreport/crash.jsp # Aborted A co-worker of mine who has the same version of Ubuntu has had the same problem, but has only happened to him once. (I get this probably 2 or 3 times a day, if not more). I have another machine running Ubuntu 10.04 with Sun Java and I have yet to see this problem. 1.0.6_20 is the java version on the 10.04 machine. My machine is running 1.6.0_22. Has anyone else had this problem? Anyone know how to keep it from happening? Also: I have tried reinstalling it and I can't use OpenJDK.

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• Are injectable classes allowed to have constructor parameters in DI?

  - by Songo

  Given the following code: class ClientClass{ public function print(){ //some code to calculate $inputString $parser= new Parser($inputString); $result= $parser->parse(); } } class Parser{ private $inputString; public __construct($inputString){ $this->inputString=$inputString; } public function parse(){ //some code } } Now the ClientClass has dependency on class Parser. However, if I wanted to use Dependency Injection for unit testing it would cause a problem because now I can't send the input string to the parser constructor like before as its calculated inside ClientCalss itself: class ClientClass{ private $parser; public __construct(Parser $parser){ $this->parser=$parser; } public function print(){ //some code to calculate $inputString $result= $this->parser->parse(); //--> will throw an exception since no string was provided } } The only solution I found was to modify all my classes that took parameters in their constructors to utilize Setters instead (example: setInputString()). However, I think there might be a better solution than this because sometimes modifying existing classes can cause much harm than benefit. So, Are injectable classes not allowed to have input parameters? If a class must take input parameters in its constructor, what would be the way to inject it properly? UPDATE Just for clarification, the problem happens when in my production code I decide to do this: $clientClass= new ClientClass(new Parser($inputString));//--->I have no way to predict $inputString as it is calculated inside `ClientClass` itself. UPDATE 2 Again for clarification, I'm trying to find a general solution to the problem not for this example code only because some of my classes have 2, 3 or 4 parameters in their constructors not only one.

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• Why would video stutter on HDMI but not on DVI?

  - by CorvT

  I've got a system running Ubuntu 12.04 with an i3 2120T CPU/GPU. When I play video through mplayer, I notice when I'm hooked up to a screen via HDMI there is a small stutter (1-2 frames) every few seconds. I don't see this happening when I connect via DVI on the same screen. Resolution and refresh rate are same for both HDMI and DVI, so I'm not sure where else the problem could be coming from. I've also tried two different screens, and different cables. I see the stutter with either HDMI-HDMI cables, or DVI-HDMI cable with DVI from the PC and HDMI into the screen. I don't see the stutter with DVI-DVI cables, or when I use HDMI-DVI cables with HDMI from the PC to DVI into the screen. I've also tried using an AMD 5XXX series card with the open source radeon driver, and saw the same problem. I then tried an nVidia GeForce 210 card with the closed source driver, and the stutter went away. To me this smells like a driver/mesa/glx issue (since the problem went away with the nvidia card/driver), but I have no idea how to track this down.

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• Lenovo Y460 Intel Driver Secondary Display Flickering

  - by ultimatebuster

  This is a part of the massive dump of problems I'm encountering with my Lenovo Y460 and Ubuntu. Problem: ATI PowerXpress doesn't really work. Doesn't work as I have to use the open source driver with hacks. Turned off ATI card at boot Details on how I accomplished that: http://ubuntuforums.org/showthread.php?p=10955831#post10955831 Installing the ATI drivers results in a failure of the intel drivers to work with Ubuntu Class (all animations have to turned off). Anyway to fix this problem to allow switchable graphics to work? The problem above has been fixed by FGLRX (Catalyst 11.6) is it compatible with kernel 2.6.39? However, there's another issue. If I connect my secondary monitor (VGA 17'') while using the Intel driver, I would not be able to use that screen as there's flickering and tearing, making the screen blurry and usable. Here's the fglrxinfo: $ fglrxinfo display: :0.0 screen: 0 OpenGL vendor string: Tungsten Graphics, Inc OpenGL renderer string: Mesa DRI Intel(R) Ironlake Mobile GEM 20100330 DEVELOPMENT OpenGL version string: 1.4 (2.1 Mesa 7.10.2) Any fixes for that? Potential related bug report on launchpad: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/750259 However I can't confirm because the video showing that is much more dramatic than what I have, mine are tiny flickering that won't be captured by video cameras as I've tried, but enough to make it blurry for humans.

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• Why is math taught "backwards"? [closed]

  - by Yorirou

  A friend of mine showed me a pretty practical Java example. It was a riddle. I got excited and quickly solved the problem. After it, he showed me the mathematical explanation of my solution (he proved why is it good), and it was completely clear for me. This seems like natural approach for me: solve problems, and generalize. This is very familiar to me, I do it all the time when I am programming: I write a function. When I have to write a similar function, I generalize the problem, grab the generic parts, and refactor them to a function, and solve the original problems as a specialization of the general function. At the university (or at least where I study), things work backwards. The professors shows just the highest possible level of the solutions ("cryptic" mathematical formulas). My problem is that this is too abstract for me. There is no connection of my previous knowledge (== reality in my sense), so even if I can understand it, I can't really learn it properly. Others are learning these formulas word-by-word, and get good grades, since they can write exactly the same to the test, but this is not an option for me. I am a curious person, I can learn interesting things, but I can't learn just text. My brain is for storing toughts, not strings. There are proofs for the theories, but they are also really hard to understand because of this, and in most of the cases they are omitted. What is the reason for this? I don't understand why is it a good idea to show the really high level of abstraction and then leave the practical connections (or some important ideas / practical motivations) out?

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• linq to sql with nservicebus table lock issue

  - by IGoor

  I am building a system using NServiceBus and my DataLayer is using Linq 2 SQL. The system is made up of 2 services. Service1 receives messages from NSB. It will query Table1 in my database and inserts a record into Table1 If a certain condition is met a new NSB message is sent to the 2nd service Service2 will update records also in Table1 when it receives messages from Service1 and it does some other non database related work. Service2 is a long running process. The problem I am having is the moment Service2 updates a record in Table1, the table is locked. The lock seems to be in place until Service2 has completed all it is processing. i.e. The lock is not released after my datacontext is disposed. This causes the query in Service1 to timeout. Once Service2 completes processing, Service1 resumes processing again without problem. So for example Service1 code may look like: int x =0; using (DataContext db = new DataContext()) { x = (from dp in db.Table1 select dp).Count(); // this line will timeout while service2 is processing Table1 t = new Table1(); t.Data = "test"; db.Table1.InsertOnSubmit(t); db.SubmitChanges(); } if(x % 50 == 0) CallService2(); The code in service2 may look like: using (DataContext db = new DataContext()) { Table1 t = db.Table1.Where(t => t.id == myId); t.Data = "updated"; db.SubmitChanges(); } // I would have expected the lock to have been released at this point, but this is not the case. DoSomeLongRunningTasks(); // lock will be released once service2 exits I don't understand why the lock is not released when the datacontext is disposed in Service2. To get around the problem I have been calling: db.ExecuteCommand("SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED"); and this works, but I am not happy using it. I want to solve this problem properly. Has any one experienced this sort of problem before and does any one know how to solve it? Why is the lock not released after the datacontext has been disposed? Thanks in advance. p.s. sorry for the extremely long post.

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• ISA Proxy server

  - by user59931

  Have a proxy at work that runs Microsoft ISA. i used to be able to connect using 11.10 with firefox no problem at all. i could either put the settings in firefox or the settings in ubuntu network proxy settings. this would give me a connection no problem ( slow due to the work network being really lame) since i upgraded with 12.10 firefox just crashes if i have any proxy settings (manual added the proxy settings). if i connect to a diffrent network without the proxy settings it works fine and doesn't crash i tried chrome to see if that would work... simular problem. chrome doesn't crash but is so slow it just times out all the time and can take 10min for a page to load.... not really sure where to go with this? i have tried a clean install of 12.04 on 2 diffrent computers and also both tried just upgrading from 11.10. Only answer i can see at the moment is role back to 11.10 :( i have tried all sorts like turning of IPv6 to see if that would make any diffrence but no joy... really am lost now. whats weird is the repositys are also really really slow through 12.04. 50 megs took an hour to download (ISA server has Ubuntu rep servers enables without authenication). really am lost

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• How to handle the different frame rate on different devices?

  - by Fenwick

  I am not quite sure how frame per second works on a web page. I have a Canvas game that involves in moving an image from point A to B, and measuring the time elapsed. The code can be as simple as: var timeStamp = Date.now(); function update(){ obj.y += obj.speed; text = "Time: "+ (Date.now() - timeStamp) + "ms"; } The function update() is called every frame. The problem is that the time elapsed is different from device to device. It is pretty short on my PC, but get longer on my iPad, and is much longer on my cell phone. I thought it is because the FPS is smaller on mobile devices, so instead of calling update() every frame, I call it every 1ms by using a setInterval. But this does not solve the problem. In my understanding, the function for setInterval is invoked based on the increment in system time, other than frame rate, so it should fix the problem. Am I missing anything here? If the setInterval function is called based on FPS, is there any way to get around with the FPS difference across devices? On a side note, I have sort of a "water simulator" on the same canvas. It involves in redrawing about 60 objects which can be 600x600 pixels for every frame, so it could be a frame rate killer. I am using Phaser.js but not really using much of its functionalities, if that helps.

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• How do you avoid name similarities between your classes and the native ones?

  - by Oscar

  I just ran into an "interesting problem", which I would like your opinion about: I am developing a system and for many reasons (meaning: abstraction, technology independence, etc) we create our own types for exchanging information. For instance: if there is a method which is called SendEmail and is invoked by the business logic, it way have a parameter of type OurCompany.EMailMessage, which is an object which is completely technology independent and contains only "business relevant data" (for instance, no information abut head encoding). Inside the SendEmail function, we get this information from our EMailMEssage object and create a MailMessage (this one is technolgy specific) object so it can be sent over the network. As you can already notice, our class has a very similar name to the "native" language class. The problem is: this is exactly what they are, email messages, so it is hard to find another meaningful name for them. Do you have this problem often? How do you manage it? Edit: @mgkrebbs just commented about using fully qualified names. This is our current approach, but a little bit too verbose, IMHO. I would like something cleaner, if possible.

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• Never Bet Against the Impossible

  - by BuckWoody

  My uncle used to say “If a man tells you that his car squirts milk in his eye when you lift the hood, don’t bet against that. You’ll end up with milk in your eye.” My friend Allen White tells me this is taken from a play (and was said about playing cards), but I think the sentiment holds, even in database work. I mentioned the other day that you should allow the other person to talk and actively listen before you propose a solution. Well, I saw a consultant “bet against the impossible”  the other day – and it bit her. She explained to the person telling her the problem that the situation simply couldn’t exist that way, and he proceeded to show her that it did. She got silent, typed a few things, muttered a little, and then said “well, must be something else.” She just couldn’t admit she was wrong. So don’t go there. If someone explains a problem to you with their database, listen with purpose, and then explore the troubleshooting steps you know to find the problem. But keep your absolutes to yourself. In fact, I have a friend that has recently sent me one of those. He connects to a system with SQL Server Management Studio (SSMS) version 2008 (if I recall correctly) and it shows a certain version number of the target system in the connection tab. Then he connects to it using SSMS 2008 R2 and gets a different number. Now, as far as I know, we didn’t change the connection string information, and that’s provided by the target system, so this is impossible. But I won’t tell him that. Not until I look a little more. :) Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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