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I write a lot of (primarily c++ and javascript) code that touches upon computational geometry and graphics and those kinds of topics, so I have found that visual diagrams have been an indispensable part of the process of solving problems.
I have determined just now that "oh, wouldn't it just be fantastic if I could so... |
How is the Morse Code representation of a letter determined?
"E" = "."
"T" = "-"
Why is it not alphabetic? As in let "A" = ".", "B" = "-", "C" =".-", etc.
I'm trying to develop an algorithm for a traversing Binary Tree filled with these letter.
My main aim is to search for a letter, like "A", but I don't know what cond... |
I'm wanting to share an authentication implementation across a web application, and web API. The web application will be ASP.NET (mostly MVC 4), the API will be mostly ASP.NET WEB API, though I anticipate it will also have a few custom modules or handlers.
I want to:
Share as much authentication implementation between... |
I am making a card game for Android where a player can choose from a selection of cards to build a deck that would contain around 60 cards. Currently, I have the entire database of cards created that the user can browse.
The next step is allowing the user to select cards and create a deck with whatever cards they would... |
I'm working on a browser based open source monitoring project that I want to be free to the community.
What I'm worried about is someone taking the project, renaming it, deploying it in the cloud and start charging people who don't even know my project exists. I know I maybe shouldn't mind, but it just sticks in my thr... |
I'm trying to find out your decision rationale of when to do what. I'm happy to provide more context, but I want to make it general for now.
|
Suppose that I have a class that implements some logic:
public MyLogicImpl implements MyLogic {
public void myLogicMethod() {
//my logic here
}
}
and somewhere else a test class:
public MyLogicImplTest {
@Test
public void testMyLogicMethod() {
/test my logic
}
}
I also have:
@WebSe... |
I'm sixteen, I'm overly interested in programming, and I'm currently taking IT classes during my mornings in high school. Last year, I tried teaching myself to code. It was quite exciting, but all I did was watch TheNewBoston's videos on YouTube for Python.
After his tutorials, I just did research, made some CMD progr... |
I am currently trying to improve my use of exceptions, and found the important distinction between exceptions that signify programming errors (e.g. someone passed null as argument, or called a method on an object after it was disposed) and those that signify a failure in the operation that is not the caller's fault (e.... |
So, I used to think that it would be a good idea to give the customer access to the issue tracking system, but now I've seen that it creates less than ideal situations, like:
Customer judging progress solely on ticket count
Developers denied to add issues to avoid customer thinking that there is less progress
Customer... |
I'm developing a commercial application that largely depends on the functionality of a library that will be developed with it. I'd like to open-source this library, because it offers functionality that is not found elsewhere and can be useful in other applications.
However, I will also use it in my own commercial appli... |
I've just read an excerpt of "Growing Object-Oriented Software" book which explains some reasons why mocking concrete class is not recommended.
Here some sample code of a unit-test for the MusicCentre class:
public class MusicCentreTest {
@Test public void startsCdPlayerAtTimeRequested() {
final MutableTime sched... |
I have a service endpoint initialized using DI. It is of the following style. This end point is used across the app.
public class CustomerService : ICustomerService
{
private IValidationService ValidationService { get; set; }
private ICustomerRepository Repository { get; set; }
public CustomerService(IVa... |
I have just started a C programming course and so far have only done the basics like printf, read a little on variables etc on the course book. The teacher has tasked us with writing a program that will take a value entered by the user, this will be the number of students in the class (25 at the moment but can be vari... |
While writing some predicates for collection filtering I have stumbled over the choice of the right words for the relation of the subject and the predicate (English is a foreign language for me). What I ended up writing was "Subjects matching this predicate..."
This seems to be incorrect, since predicates are functions... |
It is often necessary to spend time designing a solution, breaking down the design into tasks and sub tasks and estimating the time it will take to complete each task in order to produce a reasonable estimate or quote for a programming task. This process can be a serious investment of time, often without any guarantee... |
I have server with some resources; until now all these resources were requested through a browser by a human user, and the authentication was made with an username/password method, that generates a cookie with a token (to have the session open for some time).
Right now the system requires that other servers make GET re... |
I want to create a two dimensional layout of rectangular shapes, a grid made up of random sized cubes. The cubed should fit together and have equal padding or margin (space between). Kind of like a comic book layout, or more like the image attached.
How could I do this procedurally?
Practically, I would probably be us... |
Steve Yegge's The Pinoccio Problem describes a very special type of program: one that not only fulfills the original purpose of its creators, but also is capable of performing arbitrary, user-defined computations.
They typically also host a console, by which one can reprogram the software on runtime, maybe persisting t... |
I read that Facebook started out in PHP, and then to gain speed, they now compile PHP as C++ code. If that's the case why don't they:
Just program in c++? Surely there must be SOME errors/bugs when hitting a magic compiler button that ports PHP to c++ code , right?
If this impressive converter works so nicely, why sti... |
On a page twelve of "Java concurrency in practice" there is a phrase
"A good specification defines invariants constraining an object's
state and post - conditions describing the effect of its operation."
More or less I undersand the phrase untill the word "post", then it becomes a garbage.
Can you help please?
|
I'm a student working an internship at a larger company, writing small business apps in C#. I've noticed that I don't comment my code as I write it. Rather, I comment my code when I'm in the debugging stage of development. As I'm tracking down bugs, I'll run across a block that makes me think "hmm...that might confu... |
I'm wondering whether there is a performance difference between using different CSS properties to translate an element. Some properties fit different situations differently.
You can translate an element with following properties: transform, top/left/right/bottom and margin-top/left/right/bottom
In the case where you do... |
Still on my quest to compress/decompress files with a Java implementation of Huffman's coding (http://en.wikipedia.org/wiki/Huffman_coding) for a school assignment.
From the Wikipedia page, I quote:
Create a leaf node for each symbol and add it to the priority queue.
While there is more than one node in the queue:
... |
Our company's main application is a desktop program that is used at warehouses and written in C# and Windows Presentation Forms.
The next thing we want to be able to do is track when customers open up the application and when it is being used. The reason for this is so we can charge them per month, based on if they ar... |
If I take a program, and basically translate its source from some language to python, with some small changes, can I do a entirely my new lib or I have to make a "version" of the old one?
would this be a copy of the first or a new lib based in the ideas of the first?
OBS: Consider the original lib is using Apache Licen... |
We have three sets of test suites:
A "small" suite, taking only a couple of hours to run
A "medium" suite that takes multiple hours, usually ran every night (nightly)
A "large" suite that takes a week+ to run
We also have a bunch of shorter test suites, but I'm not focusing on them here.
The current methodology is to... |
We have a new developer on our team. He seems to be a smart guy (he just came in so I cannot really judge). He started with implementing some small enhancements on the project (MVC3 web application using Javascript with jQuery and Knockout).
Let's say we have two values:
A - quite complex calculation
C - constant ... |
Not sure whether this is the right place to ask this question, but here goes..
Currently I have requirement to add support for consignment transaction in our inventory module. I have a very limited understanding of what consignment means in inventory, i.e.
Customer get stocks/products from Seller without actually buy... |
I often hear the term that language A is written in language B. For example, PHP has been written C, C# is written in C++.
Can someone please explain what does that mean and if it is even correct? Does that have anything to do with the compiler of interpreter used by the language?
In addition what are the factors on wh... |
What is the most concise (yet descriptive) way of naming a subclass that only add a specific minor thing to the parent? I encountered this case a lot in WPF, where sometime I have to add a small functionality to an out-of-the-box control for specific cases.
Example: TreeView doesn't change the SelectedItem on right-cli... |
I'm trying to look up info about reading JPEG's color profile info and to my surprise there's very little open specific how-to information on that regard, but rather lots of general explanation on what it is.
Does anyone know how to find and read the color profile information from JPEG?
|
This question is inspired by the debate in the comments on this Stack Overflow question. The Google Closure Compiler documentation states the following (emphasis added):
The Closure Compiler is a tool for making JavaScript download and run faster. It is a true compiler for JavaScript. Instead of compiling from a sourc... |
I've struggled quite a bit with Eclipse and progress-monitors to try to have good progressbars which report useful progress information to the user. Inevitably the code gets cluttered with lots of things like
if (monitor.isCancelled())
return;
...
lengthyMethodCall(monitor.newChild(10));
and all over the place I... |
I want to use the .NET TPL to asynchronously do a DIR /S and search each subdirectory on a hard drive, and want to search for a word in each file... what should my API look like?
In this scenario I know that each sub directory will have 0..10000 files or 0...10000 directories. I know the tree is unbalanced and want ... |
While the core of requirements development and acceptance criteria would ideally take place during the planning meeting in order to create a better estimate, Scrum encourages continuous interaction with the product owner throughout the sprint to validate and refine user stories.
What kind of criteria is used to judge ... |
I've been a bit weary about approaching learning databases. I've dabbled into them before, and "DATA" in itself appeals to me a lot. Maintaining/searching/moving, everything about it in the abstract sense I love. (This isn't a career question, this is a learning question.)
But as RDBMS's begin to be easier to maintain,... |
I've got an web app that needs to store some non-sensitive preferences for the user. Right now I'm storing their language preference and what mode they want a window opened in by default in two cookies:
"lang" can be "en" or "de"
"mode" can be "design" or "view"
I might add a few more in the future. I'm not sure how ... |
I'm new to Haskell and I'm not really sold on the Nothing constructor. It sounds like just another silent fail that's going to create headaches down the line. It seems much more useful to throw an error so I'll have a clue what's happening.
Why am I wrong here?
|
If I have a view called, for example, ViewDetails that displays user information in labels and has a Model called ViewDetailsModel and if I want to allow the user to click a button to edit some of these details, is it considered bad practice is I pass the entire Model in the markup to a controller method which then ass... |
This has become a large frustration with the codebase I'm currently working in; many of our variable names are short and undescriptive. I'm the only developer left on the project, and there isn't documentation as to what most of them do, so I have to spend extra time tracking down what they represent.
For example, I wa... |
Let me support my question with a quick scenario.
We're writing an app for family meal planning. We'll produce daily plans with a target calorie goal and meals to achieve it for our nuclear family. Our calorie goal will be calculated for each person from their attributes (gender, age, weight, activity level).
The wei... |
Suppose I have a dictionary of ASCII words stored in uppercase. I also want to save those words into separate files so that the total word count of each file is approximately the same. By simply looking at the word I need to know which file it should be in (if it's there at all). Duplicate words should go into the... |
I've been building an android game in my spare time. It's using the libgdx library so quite a bit of the heavy lifting is done for me.
While developing, I carelessly selected datatypes for some procedures. I used a hashtable because I wanted something close to an associative array. Human readable key values. In other p... |
I am expecting a job interview for a C++, what kind of questions should I expect?
I have been programming with C for 5 years. I know what OOP is and I have been reading about it for some time. But it is most likely I can miss important details because I do not do anything real on C++.
Best Regards,
|
Does the "magic" of the JVM hinder the influence a programmer has over micro-optimisations in Java? I recently read in C++ sometimes the ordering of the data members can provide optimizations (granted, in the microsecond environment) and I presumed a programmer's hands are tied when it comes to squeezing performance fr... |
Out of curiosity, are there languages that allow you to do set arithmetic on types to create new types? Something like:
interface A {
void a();
void b();
}
interface B {
void b();
void c();
}
interface C = A & B; // has b()
interface D = A | B; // has a(), b() and c()
interface E = (A & B) ^ B; // has c()
... |
Can someone recommend a good robust "Free" testing framework for Qt?
Our requirements:
Should be able to test basic mouse click / mouse move events
Should be able to handle non-widget view components
Should have "record" capability to generate test scripts.
Should be automatable for running it daily.
We looked at:
S... |
Are there standard approaches to persisting data for every hit that a web app receives? This would be for analytics purposes (as a better alternative to log mining down the road).
Seems like Redis would be a must. Is it advisable to also use a different DB server for that table, or would Redis be enough to mitigate the... |
Do you know any programming language features that help to detect bugs early in the software development process - ideally at compile-time or else as early as possible at run-time?
Examples of well-known and effective bug-reducing features are:
Static typing and generic types: type incompatibility errors are detected ... |
I am building a moderation panel from scratch in a MVC approach and a lot of questions cropped up during development. I would like to hear from others how they handle these situations.
Error handling
Should you handle an error inside the class method or should the method return something anyway and you handle the erro... |
I always thought that the business logic has to be in the controller and that the controller, since it is the 'middle' part, stays static and that the model/view have to be capsuled via interfaces. That way you could change the business logic without affecting anything else, program multiple Models (one for each databa... |
Here's the deal: I'm looking at designing my own scripting/interpreted language for fun. I'm only in the planning stages right now; I want to make sure I have a very strong hold on exactly how I will implement everything before I start coding.
What I'm currently struggling with is concurrency. It seems to me like an ea... |
Studying this subject extensively, the most books state the following:
Quality Assurance: prevention activity. Act of inspection, reviewing..
Quality Control: testing
While there are some exceptions that mention that QA deals with just processes (planning, strategy, standard application etc.) which is IMHO much cl... |
I have developed an Android application where, typically, each view (layout.xml) displayed on the screen has it's own corresponding fragment (for the purpose of this question I may refer to this as a ViewController).
These views and Fragments/ViewControllers are appropriately named to reflect what they display. So this... |
Why do generics in Scala have erased types, and are not reifiable?
Is it due to lack of support from the JVM or for compatibility with Java libraries?
What are the advantages in general of having generics as reifiable?
|
Generics in Java are implemented using type erasure. The JLS says that the inspiration was backward compatibility. Where as on the other hand C# generics are reifiable.
Theoretically what are the advantages and disadvantages by having Generics as "erasure" or "reifiable"?
Is Java missing onto something?
|
Recently domain driven design got my attention, and while thinking about how this approach could help us I came across the following problem.
In DDD the common approach is to retrieve entities (or better, aggregate roots) from a repository which acts as a in-memory collection of these entities. After these entities hav... |
I'm trying to build up some test cases, and have read that you should try and limit the number of assertions per test case.
So my question is, what is the best way to go about testing a function w/ multiple inputs. For example, I have a function that parses a string from the user and returns the number of minutes. Th... |
One of my major complaints about C++ is how hard in practice it is to pass std library objects outside of dynamic library (ie dll/so) boundaries.
The std library is often header-only. Which is great for doing some awesome optimizations. However, for dll's, they are often built with different compiler settings that may... |
After 10+ years of java/c# programming, I find myself creating either:
abstract classes: contract not meant to be instantiated as-is.
final/sealed classes: implementation not meant to serve as base class to something else.
I can't think of any situation where a simple "class" (i.e. neither abstract nor final/sealed) ... |
Based on the discussion around this question. I'd like to know how .so files/the ELF format/the gcc toolchain avoid problems passing classes defined purely in header files (like the std library). According to Jan in that answer, the dynamic linker/loader only picks one version of such a class to load if its defined in ... |
I am having algorithm mental block in designing a way to transition from Green to Red, as smoothly as possible with a, potentially, unknown length of time to transition.
For testing purposes, I will be using 300 as my model timespan but the methodology algorithm design needs to be flexible enough to account for larger ... |
Are there patterns or libraries or any official Microsoft SDK for using Visual Studio as a specifically Task-Focused UI?
For example, both Revolution R (IDE for the R language) and SQL 2012 (and I think SQL 2008 and possibly 2005) use Visual Studio as the underlying IDE framework.
Is there an officially supported SDK... |
How do you learn a new platform/toolkit while producing working code and keeping your codebase clean?
When I know what I can do with the underlying platform and toolkit, I usually do this:
I create a new branch (with GIT, in my case)
I write a few unit tests (with JUnit, for example)
I write my code until it passes my... |
I'll be the first to say that this question is a bit... out there. But here are a couple questions I bear in mind :
Is abstraction continuous or discrete?
Is there a single unit of abstraction?
But I'm not sure those questions are truly answerable or even really makes sence. My naive answer would be something along t... |
I've recently written a piece of software (without any other contributors) for a company which I part own. I was wondering if I could distribute it with the following permission notice, which is a modified version of the MIT License. Are there any obvious risks if I do distribute with this licence and does it give me t... |
I'm working on an array structure that will be used as the data source for a report template in a web app.
The data comes from relatively complex SQL queries that return one or many rows as one dimensional associative arrays. In the case of many, they are turned into two dimensional indexed array.
The data is complex a... |
I have to make a rather complex system for my diploma work. Logically it will consist of the following components:
Database
Web-service
Management with web interface
Client iOS application that will consume web-service
I decided to implement all the first three components under .NET.
Firstly I will create a database ... |
So lets say we have a clustered environment setup. We have a cluster SQL Server (I don't know exactly how its done but lets just say its been done for the sake of argument). Now if a website or application is trying to access that database for read/write (say an ASP.NET app or a C# Winforms app) and during that time SQ... |
I'm writing an app that does something like a custom number (license) plate generator tool where if I ask for the plate "robin" it will suggest I try:
r0bin
rob1n
r0b1n
Are there any published algorithms which can do this? It has to be able to handle replacing single letters with multiples, e.g. m with rn and vise-ve... |
As per Wikipedia:
In computer programming, a function may be described as pure if both these statements about the function hold:
The function always evaluates the same result value given the same argument value(s). The function result value cannot depend on any hidden information or state that may change as program ... |
Is there a single scenario (other than compatibility with ancient JVMs) where using synchronized is preferable to using a Lock? Can anyone justify using wait or notify over the newer systems?
Is there any algorithm that must use one of them in its implementation?
I see a previous questions that touched on this matter b... |
So for a clustered environment - how would this work with your apps?
What about your own custom .NET apps? Would there be a special way to develop them? I know that you could create a simple Hello world app, and cluster that, but that wouldn't be something you could see in terms of the UI or anything. So they would eff... |
On my great quest for compressing/decompressing files with a Java implementation of Huffman coding (http://en.wikipedia.org/wiki/Huffman_coding) for a school assignment, I am now at the point of building a list of prefix codes. Such codes are used when decompressing a file. Basically, the code is made of zeroes and one... |
I know that this will be a difficult question to answer without context, but hopefully there are at least some good guidelines to share on this. The questions are at the bottom if you want to skip the details. Most are about OOP in general.
Begin context. I am a jr dev on a PHP application, and in general the devs I wo... |
I have a situation where my parent knows about it's child (duh) but I want the child to be able to reference the parent. The reason for this is that I want the child to have the ability to designate itself as most important or least important when it feels like it. When the child does this, it moves it to the top or bo... |
Doing some reading on Stack Overflow, I've found a lot of information suggesting that proper organization of a file system is crucial to a well-written web app. One of the key pieces of evidence is high-frequency references to "separation of concerns" in questions related to keeping programs organized.
Now, I've found... |
Also according to Software Testing By Srinisvasan Desikan, Gopalaswamy Ramesh or ISTQB text books. Quality assurance is e.g. reviewing products, inspections, walkthroughs to see if all standards are being followed. This is preventive activity. I cannot see how this can be preventive?
For the references:
defect preven... |
Imagine you have such routines
/*just do X. Fail if any precondition is not met*/
doX()
/*take care of preconditions and then do X*/
takeCareOfPreconditionsCheckIfNeededAtAllAndThenDoX()
A little bit more concrete example:
/*create directory. Most probably fail with error if any precondition is not met (folder alrea... |
I have a Kendo UI Grid that I am currently allowing filtering on multiple columns. I am wondering if there is a an alternative approach removing the outer switch statement?
Basically I want to able to create an extension method so I can filter on a IQueryable<T> and I want to drop the outer case statement so I don't ... |
Is it possible to achieve Continuous Delivery using TFS e.g. Windows Service? There are > 1000 posts on how to use msdeploy with TFS for WEB projects.
I am trying to understand why there are no resources such as blogs, articles, msdn or best practises for Continuous Delivery for Windows service using TFS.
I am not sur... |
I'm never sure when a project is far enough along to first commit to source control. I tend to put off committing until the project is 'framework-complete,' and I primarily commit features from then on. (I haven't done any personal projects large enough to have a core framework too big for this.) I have a feeling this ... |
I would like some pointers to information which would help me understand how to go about providing the ability to filter a list of entities by their attributes as well as by attributes of related entities.
As an example, imagine a web app which provides order management of some kind. Orders and related entities are sto... |
2¹⁶-1 & 2⁵ = 2⁵ (or? obviously ?)
A developer asked me today what is bitwise 65535 & 32 i.e. 2¹⁶-1 & 2⁵ = ?
I thought at first spontaneously 32 but it seemed to easy whereupon I thought for several minutes and then answered 32. 32 seems to have been the correct answer but how? 65535=2¹⁶-1=1111111111111111 (but it doesn... |
It is a bit ironic, yesterday I answered a question related to this topic that was marked to be good and today I'm the one who asks. These are my thoughts and a question:
Also let's agree on the terms: QA is a set of activities that defines and implements processes during SW development. The common tool is the process ... |
First of all let me explain who I am: I am a PHP Developer working for a company developing their CMS which handles online stores, data feeds and other content like blogs. I have been programming for 6 years and 4 of those have been in PHP. (I used to be a C# developer).
My question is regarding PHP frameworks. I see... |
For the past 2-3 weeks I've been searching for different ways to implement custom video streaming and in more general video capturing and manipulating, going through DVR-cards, Video Capture Cards and stuff like that.
Somehow JMF was able to stay out of my sight for all this time, but since I find out about it I'm mor... |
In school, I've been told many times to stop using public for my variables. I haven't asked why yet.
This question: Are Java's public fields just a tragic historical design flaw at this point? seems kinda related to this. However, they don't seem to discuss why is it "wrong", but instead focus on how can they use them ... |
I understand the Heap memory divisions such as Young, tenured and Perm Gen.
But I'm just curious from where is the memory used for performing the Garbage Collector itself? Is it from any of these memory spaces or in the thread stacks ?
|
I have made a POS System for a client of mine using MS Access Server-Client approach.
He asked me to brand his software to allow only a certain "number" of users (cashiers) to access the POS System, and must be determined to the license his client will buy.
EX: 10 User License = 10 Cashiers ( not necessarily 10 users, ... |
Say, that you are handling a multi-step process (like a complex registration form, with a number of steps the user has go through in order). You need to be able to save the current state of the process (e.g. so the user can come back to that registration form later and continue form the step where they were left off).
... |
Say I've to develop an app that runs on iOS, Android and Windows 8 Mobile. Now all three platforms are technically in different program languages. The only 'reuse' that I can see is that of the boxes-and-lines drawings (UML :) charts and nothing else.
So how do companies/programmers manage the variation of the same pro... |
It is said that the Kanban methodology is suited for software maintenance and support areas, whereas Scrum is more suited for new product development. No process or methods are complete. Using the right one will help you succeed, but they will not guarantee success.
Is there a study showing which agile approach is best... |
First of all I'm developing a parser for an XML-based format for 3D graphics called XGL.
But this question can be applied to any situation when you have fields in your class that are optional i.e. the value of this field can be missing.
As I was taking a Scala course on coursera there was an interesting pattern when yo... |
I'm working on a Java project and I would like to add a plug-in system. More precisely, I would like to let the user design his own module, pack it into a jar, leave it in a "plugins/" subfolder of my application and be done with it. I've managed to get a child classloader to instantiate objects of classes located in e... |
I've been working with MVVM for a while, but I've recently started using MVPVM and I want to know how to create hierarchial View/ViewModel/Presenter app using this pattern.
In MVVM I would typically build my application using a hierarchy of Views and corresponding ViewModels e.g. I might define 3 views as follows:
The... |
We have a large project that has nearly 20 modules on it. We want to use WCF for the business layer.
We have thought of three ways to implement WCF our project:
Use only one datacontract and one operation contract. Send
ClassName, MethodName to operation and create class by reflection
then invoke the method in WCF sid... |
I am making program in Java in which I am making Dialog box, button, checkbox, etc. SWT widgets.
Now my problem is, I want like if in one execution button is made and in second execution checkbox is made then they both should display in one box.
So I need to store that box object.
How can I do that?
|
I have a query on whether the following requirements would need to be designed via Business Rules - this is for a JEE based application where currently this is coded as part of the Business logic.
System will create a tax account for every city, county and district
combination that imposes tax for only certain citie... |
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