Search Results

Search found 14074 results on 563 pages for 'programmers'.

Page 157/563 | < Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >

  • Java regex patterns - compile time constants or instance members?

    - by KepaniHaole
    Currently, I have a couple of singleton objects where I'm doing matching on regular expressions, and my Patterns are defined like so: class Foobar { private final Pattern firstPattern = Pattern.compile("some regex"); private final Pattern secondPattern = Pattern.compile("some other regex"); // more Patterns, etc. private Foobar() {} public static Foobar create() { /* singleton stuff */ } } But I was told by someone the other day that this is bad style, and Patterns should always be defined at the class level, and look something like this instead: class Foobar { private static final Pattern FIRST_PATTERN = Pattern.compile("some regex"); private static final Pattern SECOND_PATTERN = Pattern.compile("some other regex"); // more Patterns, etc. private Foobar() {} public static Foobar create() { /* singleton stuff */ } } The lifetime of this particular object isn't that long, and my main reason for using the first approach is because it doesn't make sense to me to hold on to the Patterns once the object gets GC'd. Any suggestions / thoughts?

    Read the article

  • Working as an entry .Net Developer in the USA [closed]

    - by Abdullah
    I just have a question about .net entry level jobs in VA. I am a master degree student in field of software engineering but I am graduated from department of physics. I decided to work on Java first, but I have changed my mind because I don't have any Java programming background except Java class in master degree so I decided to work on C# because it was easy to me to work with Visual Studio and it's fun to me to work with SQL database and HTML stuffs. And I am a member of a IT consultant company in Reston where I took course from there about .net and I created online recruitment system for their web site. Now I am applying for CPT (internship) but I didn't work in a company as a .net developer so I don't have experience. Here is my question. If I get CPT and find a job, what do software companies want from an entry level .net developer? and what do they ask as interview questions?

    Read the article

  • Beginning programming for real clients, what copyright should I put in the code?

    - by Igor Marvinsky
    Hello. So far, I've been writing projects for my friends and friends of my friends, which required no legal stuff. Now I've moved on to freelance programming on websites like vworker.com and I'm wondering what should I put in the comments on top of the code. I'm not doing big, serious serious projects, just frontends and scrapers/bots for what I gather is personal use. Would my usual // Written by Igor Marvinsky, 2011 be enough?

    Read the article

  • Techniques to read code written by others?

    - by Simon
    Are there any techniques that you find useful or follow when it comes to reading and understanding code written by others when Direct Knowledge Transfer/meeting the person who wrote the code is not an option. One of the techniques that I follow when dealing with legacy code is by adding additional debugging statements and based on the values I figure out the flow/logic. This can be tedious at times. Hence the reason behind this question, Are there any other techniques being widely practiced or that you personally follow when it comes to dealing with code written by other people/colleagues/open-source team?

    Read the article

  • What electronic user-story-mapping tools can you recommend?

    - by azheglov
    Agile software development relies heavily on a work item type called user stories. For example, you have a backlog full of user stories and you can select a few of them to work on during the next sprint. But where and how do you find user stories to put into the backlog? There is a popular technique for doing that called story mapping. Jeff Patton invented it and here is the definitive guide on how to do it. The question is, what electronic tools are out there that support Patton's story-mapping technique? I've done a bit of research, found Pivotal and Rally plug-ins (but I'm not a customer of either) and I'm currently experimenting with SilverStories. What other tools are out there? What have you used? What do you (not) recommend? Why? UPDATE: Some people who wrote comments seem to lean towards an answer that applying this technique is simply impossible with an electronic tool and we should just accept that. Can't someone write it up as an answer?

    Read the article

  • Win32 and Win64 programming in C sources?

    - by Nick Rosencrantz
    I'm learning OpenGL with C and that makes me include the windows.h file in my project. I'd like to look at some more specific windows functions and I wonder if you can cite some good sources for learning the basics of Win32 and Win64 programming in C (or C++). I use MS Visual C++ and I prefer to stick with C even though much of the Windows API seems to be C++. I'd like my program to be portable and using some platform-indepedent graphics library like OpenGL I could make my program portable with some slight changes for window management. Could you direct me with some pointers to books or www links where I can find more info? I've already studied the OpenGL red book and the C programming language, what I'm looking for is the platform-dependent stuff and how to handle that since I run both Linux and Windows where I find the development environment Visual Studio is pretty good but the debugger gdb is not available on windows so it's a trade off which environment i'll choose in the end - Linux with gcc or Windows with MSVC. Here is the program that draws a graphics primitive with some use of windows.h This program is also runnable on Linux without changing the code that actually draws the graphics primitive: #include <windows.h> #include <gl/gl.h> LRESULT CALLBACK WindowProc(HWND, UINT, WPARAM, LPARAM); void EnableOpenGL(HWND hwnd, HDC*, HGLRC*); void DisableOpenGL(HWND, HDC, HGLRC); int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { WNDCLASSEX wcex; HWND hwnd; HDC hDC; HGLRC hRC; MSG msg; BOOL bQuit = FALSE; float theta = 0.0f; /* register window class */ wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_OWNDC; wcex.lpfnWndProc = WindowProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(NULL, IDI_APPLICATION); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH); wcex.lpszMenuName = NULL; wcex.lpszClassName = "GLSample"; wcex.hIconSm = LoadIcon(NULL, IDI_APPLICATION);; if (!RegisterClassEx(&wcex)) return 0; /* create main window */ hwnd = CreateWindowEx(0, "GLSample", "OpenGL Sample", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 256, 256, NULL, NULL, hInstance, NULL); ShowWindow(hwnd, nCmdShow); /* enable OpenGL for the window */ EnableOpenGL(hwnd, &hDC, &hRC); /* program main loop */ while (!bQuit) { /* check for messages */ if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { /* handle or dispatch messages */ if (msg.message == WM_QUIT) { bQuit = TRUE; } else { TranslateMessage(&msg); DispatchMessage(&msg); } } else { /* OpenGL animation code goes here */ glClearColor(0.0f, 0.0f, 0.0f, 0.0f); glClear(GL_COLOR_BUFFER_BIT); glPushMatrix(); glRotatef(theta, 0.0f, 0.0f, 1.0f); glBegin(GL_TRIANGLES); glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(0.0f, 1.0f); glColor3f(0.0f, 1.0f, 0.0f); glVertex2f(0.87f, -0.5f); glColor3f(0.0f, 0.0f, 1.0f); glVertex2f(-0.87f, -0.5f); glEnd(); glPopMatrix(); SwapBuffers(hDC); theta += 1.0f; Sleep (1); } } /* shutdown OpenGL */ DisableOpenGL(hwnd, hDC, hRC); /* destroy the window explicitly */ DestroyWindow(hwnd); return msg.wParam; } LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) { switch (uMsg) { case WM_CLOSE: PostQuitMessage(0); break; case WM_DESTROY: return 0; case WM_KEYDOWN: { switch (wParam) { case VK_ESCAPE: PostQuitMessage(0); break; } } break; default: return DefWindowProc(hwnd, uMsg, wParam, lParam); } return 0; } void EnableOpenGL(HWND hwnd, HDC* hDC, HGLRC* hRC) { PIXELFORMATDESCRIPTOR pfd; int iFormat; /* get the device context (DC) */ *hDC = GetDC(hwnd); /* set the pixel format for the DC */ ZeroMemory(&pfd, sizeof(pfd)); pfd.nSize = sizeof(pfd); pfd.nVersion = 1; pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER; pfd.iPixelType = PFD_TYPE_RGBA; pfd.cColorBits = 24; pfd.cDepthBits = 16; pfd.iLayerType = PFD_MAIN_PLANE; iFormat = ChoosePixelFormat(*hDC, &pfd); SetPixelFormat(*hDC, iFormat, &pfd); /* create and enable the render context (RC) */ *hRC = wglCreateContext(*hDC); wglMakeCurrent(*hDC, *hRC); } void DisableOpenGL (HWND hwnd, HDC hDC, HGLRC hRC) { wglMakeCurrent(NULL, NULL); wglDeleteContext(hRC); ReleaseDC(hwnd, hDC); }

    Read the article

  • Am I copy/paste programmer ?

    - by Searock
    When ever I am stuck with a particular problem, I search for a solution in Google. And then I try to understand the code and tweak it according to my requirement. For example recently I had asked a question Reading xml document in firefox in stack overflow. Soufiane Hassou gave me a link to w3schools, where I found a example on parsing xml document, I understood how the example works, but I copied the code and tweaked it according to my requirement, since I don't like typing much. So does this make me a copy/paste programmer? How do you say if a person is a copy/paste programmer ? Thanks.

    Read the article

  • Is this method pure?

    - by Thomas Levesque
    I have the following extension method: public static IEnumerable<T> Apply<T>( [NotNull] this IEnumerable<T> source, [NotNull] Action<T> action) where T : class { source.CheckArgumentNull("source"); action.CheckArgumentNull("action"); return source.ApplyIterator(action); } private static IEnumerable<T> ApplyIterator<T>(this IEnumerable<T> source, Action<T> action) where T : class { foreach (var item in source) { action(item); yield return item; } } It just applies an action to each item of the sequence before returning it. I was wondering if I should apply the Pure attribute (from Resharper annotations) to this method, and I can see arguments for and against it. Pros: strictly speaking, it is pure; just calling it on a sequence doesn't alter the sequence (it returns a new sequence) or make any observable state change calling it without using the result is clearly a mistake, since it has no effect unless the sequence is enumerated, so I'd like Resharper to warn me if I do that. Cons: even though the Apply method itself is pure, enumerating the resulting sequence will make observable state changes (which is the point of the method). For instance, items.Apply(i => i.Count++) will change the values of the items every time it's enumerated. So applying the Pure attribute is probably misleading... What do you think? Should I apply the attribute or not?

    Read the article

  • Clean way to use mutable implementation of Immutable interfaces for encapsulation

    - by dsollen
    My code is working on some compost relationship which creates a tree structure, class A has many children of type B, which has many children of type C etc. The lowest level class, call it bar, also points to a connected bar class. This effectively makes nearly every object in my domain inter-connected. Immutable objects would be problematic due to the expense of rebuilding almost all of my domain to make a single change to one class. I chose to go with an interface approach. Every object has an Immutable interface which only publishes the getter methods. I have controller objects which constructs the domain objects and thus has reference to the full objects, thus capable of calling the setter methods; but only ever publishes the immutable interface. Any change requested will go through the controller. So something like this: public interface ImmutableFoo{ public Bar getBar(); public Location getLocation(); } public class Foo implements ImmutableFoo{ private Bar bar; private Location location; @Override public Bar getBar(){ return Bar; } public void setBar(Bar bar){ this.bar=bar; } @Override public Location getLocation(){ return Location; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); if(foo!=null) foo.addBar(bar); return foo; } } I felt the basic approach seems sensible, however, when I speak to others they always seem to have trouble envisioning what I'm describing, which leaves me concerned that I may have a larger design issue then I'm aware of. Is it problematic to have domain objects so tightly coupled, or to use the quasi-mutable approach to modifying them? Assuming that the design approach itself isn't inherently flawed the particular discussion which left me wondering about my approach had to do with the presence of business logic in the domain objects. Currently I have my setter methods in the mutable objects do error checking and all other logic required to verify and make a change to the object. It was suggested that this should be pulled out into a service class, which applies all the business logic, to simplify my domain objects. I understand the advantage in mocking/testing and general separation of logic into two classes. However, with a service method/object It seems I loose some of the advantage of polymorphism, I can't override a base class to add in new error checking or business logic. It seems, if my polymorphic classes were complicated enough, I would end up with a service method that has to check a dozen flags to decide what error checking and business logic applies. So, for example, if I wanted to have a childFoo which also had a size field which should be compared to bar before adding par my current approach would look something like this. public class Foo implements ImmutableFoo{ public void addBar(Bar bar){ if(!getLocation().equals(bar.getLocation()) throw new LocationException(); this.bar=bar; } } public interface ImmutableChildFoo extends ImmutableFoo{ public int getSize(); } public ChildFoo extends Foo implements ImmutableChildFoo{ private int size; @Override public int getSize(){ return size; } @Override public void addBar(Bar bar){ if(getSize()<bar.getSize()){ throw new LocationException(); super.addBar(bar); } My colleague was suggesting instead having a service object that looks something like this (over simplified, the 'service' object would likely be more complex). public interface ImmutableFoo{ ///original interface, presumably used in other methods public Location getLocation(); public boolean isChildFoo(); } public interface ImmutableSizedFoo implements ImmutableFoo{ public int getSize(); } public class Foo implements ImmutableSizedFoo{ public Bar bar; @Override public void addBar(Bar bar){ this.bar=bar; } @Override public int getSize(){ //default size if no size is known return 0; } @Override public boolean isChildFoo return false; } } public ChildFoo extends Foo{ private int size; @Override public int getSize(){ return size; } @Override public boolean isChildFoo(); return true; } } public class Controller{ Private Map<Location, Foo> fooMap; public ImmutableSizedFoo addBar(Bar bar){ Foo foo=fooMap.get(bar.getLocation()); service.addBarToFoo(foo, bar); returned foo; } public class Service{ public static void addBarToFoo(Foo foo, Bar bar){ if(foo==null) return; if(!foo.getLocation().equals(bar.getLocation())) throw new LocationException(); if(foo.isChildFoo() && foo.getSize()<bar.getSize()) throw new LocationException(); foo.setBar(bar); } } } Is the recommended approach of using services and inversion of control inherently superior, or superior in certain cases, to overriding methods directly? If so is there a good way to go with the service approach while not loosing the power of polymorphism to override some of the behavior?

    Read the article

  • Web to Print system - which client side technology should I use

    - by mr null
    I'm getting started to develop Web to Print system. My main concern is which client-side techology should I use: jQuery/CSS Flex/ActionScript or something else? For now, idea is that user/customer choose Product eg: Business card Attributes: Dimensions,Paper type, ... etc Template or blank Adjust product (editor) Preview & order Output should be PDF 300dpi. My main issue is: adding/adjusting text in editor. (font size, font family...). Because application should be cross browser. And I think that 10px Arial can't be the same in Firefox 5 and IE 8. It must be pixel perfect in every browser. If somebody order $100 of business cards, and text is different that he/she saw when ordering - that is a big problem. So, Flash platform should be the answer. But, as I see it's dying technology, 2012 is here - HTML5 is replacing Flash rapidly. I hope that you understand me, so every guideline or few smart words would be very appreciating.

    Read the article

  • Javascript slider Image and text from php, scrollable in groups by indexes

    - by Roberto de Nobrega
    I am looking for a javascript solution that slides images with text, pulled from php. This slider will slide in groups by indexes in points. I was googling, but nothing as I need. I am going to make an example. Imagine 10 products. I need to show the principal picture, and a text below the image. It is going to show 6 products, and with points (indexes), I click and the group slides to the next group. Do you know some script.?? I know the php code, but I am a newbie with javascript.! Thanks.!! PD. I am lost of where i have to put this question. So, If this was a wrong place, let me know, and accept my apologises.! ;)

    Read the article

  • Number crunching algo for learning multithreading?

    - by Austin Henley
    I have never really implemented anything dealing with threads; my only experience with them is reading about them in my undergrad. So I want to change that by writing a program that does some number crunching, but splits it up into several threads. My first ideas for this hopefully simple multithreaded program were: Beal's Conjecture brute force based on my SO question. Bailey-Borwein-Plouffe formula for calculating Pi. Prime number brute force search As you can see I have an interest in math and thought it would be fun to incorporate it into this, rather than coding something such as a server which wouldn't be nearly as fun! But the 3 ideas don't seem very appealing and I have already done some work on them in the past so I was curious if anyone had any ideas in the same spirit as these 3 that I could implement?

    Read the article

  • From physics to Java programmer?

    - by inovaovao
    I'm a physics phd with little actual programming experience. I've always liked programming and played around with Basic and Pascal (also VB and Delphi) as a teen, but the largest actual project I completed was an assignement for the introductory computer science class in university where I wrote a nice little program (about 1500 lines of pascal) to display functions of 2 variables in 3D. I've had also a couple other projects of a few hundred lines range, but during my phd I didn't have (or take) the time to program more (string theory is hard guys!), beside playing around with ruby. Now I've decided that I'm more interested in programming than in physics and started to learn Java (hoping to pass the certification exam next week) and OO design. Still, I have trouble deciding on what to focus next (Java EE? Web development? algorithms and C programming?) in order to maximize my employement chances. Bear in mind that I'm aiming (mostly) at the swedish job market and that I'm 30 years old. So for the questions: Do you think that I have any chances to start and make a career in IT and programming coming from physics? What would be the best strategy to maximize my value in the field? Do you have suggestions as to where my physics background might be useful?

    Read the article

  • Is ASP.NET MVC completely (and exclusively) based on conventions?

    - by Mike Valeriano
    --TL;DR Is there a "Hello World!" ASP.NET MVC tutorial out there that doesn't rely on conventions and "stock" projects? Is it even possible to take advantage of the technology without reusing the default file structure, and start from a single "hello_world.asp" file or something (like in PHP)? Am I completely mistaken and I should be looking somewhere else, maybe this? I'm interested in the MVC framework, not Web Forms --Background I've played a bit with PHP in the past, just for fun, and now I'm back to it since web development became relevant for me once again. I'm no professional, but I try to gain as much knowledge and control over the technology I'm working with as possible. I'm using Visual Studio 2012 for C# - my "desktop" language of choice - and since I got the Professional Edition from Dreamspark, the Web Development Tools are available, including ASP.NET MVC 4. I won't touch Web Forms, but the MVC Framework got my attention because the MVC pattern is something I can really relate to, since it provides the control I want but... not quite. Learning PHP was easy - and right form the start I could just create a "hello_world.php" file and just do something like this for immediate results: <!-- file: hello_world.php --> <?php> echo "Hello World!"; <?> But I couldn't find a single ASP.NET (MVC) tutorial out there (I'll be sure to buy one of the upcoming MVC 4 books, only a month away or so) that would start like that. They all start with a sample project, building up knowledge from the basics and heavily using conventions as they go along. Which is fine, I suppose, but it's now the best way for me to learn things. Even the "Empty" project template for a new ASP.NET MVC 4 Application in VS2012 is not empty at all: several files and folders are created for you - much like a new C# desktop application project, but with C# I can in fact start from scratch, creating the project structure myself. It is not the case with PHP: I can choose from a plethora of different MVC frameworks I can just create my own framework I can just skip frameworks altogether, and toss random PHP along with my HTML on a single file and make it work I understand the framework needs to establish some rules, but what if I just want to create a single page website with some C# logic behind it? Do I really need to create a whole bloat of files and folders for the sake of convention? Also, please understand that I haven't gotten far on any of those tutorials mainly because of this reason, but, if that's the only way to do it, I'll go for it using one of the books I've mentioned before. This is my first contact with ASP.NET but from the few comparisons I've read, I believe I should stay the hell away from Web Forms. Thank you. (Please forgive the broken English - it is not my primary language.)

    Read the article

  • Best exception handling practices or recommendations?

    - by user828584
    I think the two main problems with my programs are my code structure/organization and my error handling. I'm reading Code Complete 2, but I need something to read for working with potential problems. For example, on a website, if something can only happen if the user tampers with data via javascript, do you write for that? Also, when do you not catch errors? When you write a class that expects a string and an int as input, and they aren't a string and int, do you check for that, or do you let it bubble up to the calling method that passed incorrect parameters? I know this is a broad topic that can't be answered in a single answer here, so what I'm looking for is a book or resource that's commonly accepted as teaching proper exception handling practice.

    Read the article

  • UML class diagram - can aggregated object be part of two aggregated classes?

    - by user970696
    Some sources say that aggregation means that the class owns the object and shares reference. Lets assume an example where a company class holds a list of cars but departments of that company has list of cars used by them. class Department { list<Car> listOfCars; } class Company { list<Car> listOfCars; //initialization of the list } So in UML class diagram, I would do it like this. But I assume this is not allowed because it would imply that both company and department own the objects.. [COMPANY]<>------[CAR] [DEPARTMENT]<>---| //imagine this goes up to the car class

    Read the article

  • How to manage an issue tracker's backlog

    - by Josh Kelley
    We've been dutifully using Trac for several years now, and our "active tickets" list has grown to almost 200 items. These include bugs that are too low priority and too complicated to fix for now, feature requests that have been deferred, issues that have never really generated complaints but everyone agrees ought to be fixed someday, planned code refactorings and other design infelicities that we don't want to lose track of, etc. As a result, with almost 200 of these issues, the list is almost overwhelming; it's no longer useful as a source of what needs to be worked on right now. What's the best way to keep track of issues of this sort? Part of the problem is that some of these issues are such a low priority that they may never get done. I hate to lose track of these items (similar to not wanting to throw something out of my house in case I might need it someday); do I need to throw them out regardless (by marking them as wontfix) and assume I can find them in the future if I ever do need them?

    Read the article

  • Generalized Ajax function [migrated]

    - by TecBrat
    Not sure if this question will be considered "off topic". If it is, I'll remove it, but: I hadn't see this yet so I wrote it and would like to know if this is a good approach to it. Would anyone care to offer improvements to it, or point me to an example of where someone else has already written it better? function clwAjaxCall(path,method,data,asynch) { var xmlhttp; if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari xmlhttp=new XMLHttpRequest(); } else {// code for IE6, IE5 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP"); } if(asynch) { xmlhttp.onreadystatechange=function() { if (xmlhttp.readyState==4 && xmlhttp.status==200) { //alert(xmlhttp.responseText); //var newaction=xmlhttp.responseText; //alert('Action becomes '+newaction); return xmlhttp.responseText; } } } if(method=='GET'){path=path+"/?"+data;} xmlhttp.open(method,path,asynch); if(method=='GET'){xmlhttp.send();}else{xmlhttp.send(data);} if (!asynch){return xmlhttp.responseText;} } I then called it like Just Testing <script type="text/javascript" src="/mypath/js/clwAjaxCall.js"></script> <script type="text/javascript"> document.write("<br>More Testing"); document.write(clwAjaxCall("http://www.mysite.com",'GET',"var=val",false)); </script>

    Read the article

  • Is there a canonical book for learning Java as an experienced developer?

    - by Steven Elliott Jr
    I have been a .NET developer now for about the past 5/6 years give or take. I have never done any professional Java development and the last time I really touched it was probably back in college. I have been toying with the Scala language a little bit but nothing serious. Recently, I've been offered an opportunity to do some pretty cool work, but using Java instead of .NET. I think I can get by alright with my current skill set, meaning I already know how to program well and am familiar with languages such as C# and C++, etc. So, the syntax and all that language stuff are really not a problem. What I need is a really good reference book and a book about how to think in Java. Each language/Framework/Stack tries to address things a certain way and I'm sure Java is no different. What are some great Java books that you simply can't live without? Are there any books that talk about the most important parts of Java that must be understood before all else? As a side note, I will be doing mostly Java web development. Not really 100% on what types of stuff they are using for persistence, framework, server, etc.

    Read the article

  • Convert filenames to their checksum before saving to prevent duplicates. Is is a smart thing to do?

    - by Xananax
    TL;DR:what the title says I am developing some sort of image board in PHP. I was thinking of changing each image's filename to it's checksum prior to saving it. This way, I might be able to prevent duplicates. I know this wouldn't work for two images that are the same but differ in size or level of compression or whatnot, but this method would allow for an early check. What bugs me is that I never saw this method implemented anywhere, so I was wondering if there is a catch to it. Maybe it is just more efficient to keep the original filename and store the hash in DB? Maybe the whole method is just not useful and my question is moot? What do you think? On a side note, I don't really get how hashes are calculated so I was wondering, if my first question checks out, if it would be possible to calculate the likeness that two images are similar by comparing hashes (levenshtein or something of the sort).

    Read the article

  • How are minimum system requirements determined?

    - by Michael McGowan
    We've all seen countless examples of software that ships with "minimum system requirements" like the following: Windows XP/Vista/7 1GB RAM 200 MB Storage How are these generally determined? Obviously sometimes there are specific constraints (if the program takes 200 MB on disk then that is a hard requirement). Aside from those situations, many times for things like RAM or processor it turns out that more/faster is better with no hard constraint. How are these determined? Do developers just make up numbers that seem reasonable? Does QA go through some rigorous process testing various requirements until they find the lowest settings with acceptable performance? My instinct says it should be the latter but is often the former in practice.

    Read the article

  • Building massively scalable systems, where to start? [closed]

    - by Mahmoud Hossam
    Recently, I've been seeing these job postings about building scalable systems using Java, and some of the technologies mentioned were: Cassandra Thrift Hadoop MapReduce Among others. How can I get started with these technologies? Is there something else I need to know before actually learning any of these technologies? Maybe some general concepts about building highly available and scalable systems? I already know Java SE, so I won't be starting from scratch.

    Read the article

  • Empirical evidence for choice of programming paradigm to address a problem

    - by Graham Lee
    The C2 wiki has a discussion of Empirical Evidence for Object-Oriented Programming that basically concludes there is none beyond appeal to authority. This was last edited in 2008. Discussion here seems to bear this out: questions on whether OO is outdated, when functional programming is a bad choice and the advantages and disadvantages of AOP are all answered with contributors' opinions without reliance on evidence. Of course, opinions of established and reputed practitioners are welcome and valuable things to have, but they're more plausible when they're consistent with experimental data. Does this evidence exist? Is evidence-based software engineering a thing? Specifically, if I have a particular problem P that I want to solve by writing software, does there exist a body of knowledge, studies and research that would let me see how the outcome of solving problems like P has depended on the choice of programming paradigm? I know that which paradigm comes out as "the right answer" can depend on what metrics a particular study pays attention to, on what conditions the study holds constant or varies, and doubtless on other factors too. That doesn't affect my desire to find this information and critically appraise it. It becomes clear that some people think I'm looking for a "turn the crank" solution - some sausage machine into which I put information about my problem and out of which comes a word like "functional" or "structured". This is not my intention. What I'm looking for is research into how - with a lot of caveats and assumptions that I'm not going into here but good literature on the matter would - certain properties of software vary depending on the problem and the choice of paradigm. In other words: some people say "OO gives better flexibility" or "functional programs have fewer bugs" - (part of) what I'm asking for is the evidence of this. The rest is asking for evidence against this, or the assumptions under which these statements are true, or evidence showing that these considerations aren't important. There are plenty of opinions on why one paradigm is better than another; is there anything objective behind any of these?

    Read the article

  • Sorting versus hashing

    - by Paul Siegel
    My problem is as follows. I have an array of n strings with m < n of them distinct. I want to create a one-to-one function which assigns each of the m distinct strings to the numbers 0 ... m-1. For example, if my strings are: Bob, Amy, Bob, Charlie, Amy then the function: Bob -> 0, Amy -> 1, Charlie -> 2 would meet my needs. I have thought of three possible approaches: Sort the list of strings, remove duplicates, and construct the function using a search algorithm. Create a hash table and check each string to see if it is already in the table before inserting it. Sort the list of strings, remove duplicates, and put the resulting list into a hash table. My code will be written in Java, and I will likely use standard Java algorithms: merge sort for sorting, binary search for searching, and whatever the standard Java hash table algorithm is. Question: Assume that after creating the function I will have to evaluate it on each of the n original strings. Which of the three approaches is fastest? Is there a better way? Part of the problem is that I don't really know what's going on "under the hood" in standard hashing algorithms. Any help would be appreciated.

    Read the article

  • How to implement Cache in web apps?

    - by Jhonnytunes
    This is really two questions. Im doing a project for the university for storing baseball players statitics, but from baseball data I have to calculate the score by year for the player who is beign displayed. The background is, lets say 10, 000 users hit the player "Alex Rodriguez", the application have to calculate 10, 000 the A-Rod stats by years intead of just read it from some where is temporal saved. Here I go: What is the best method for caching this type of data? Do I have to used the same database, and some temporal values on the same database, or create a Web Service for that? What reading about web caching so you recommend?

    Read the article

< Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >