Search Results

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

Page 102/563 | < Previous Page | 98 99 100 101 102 103 104 105 106 107 108 109  | Next Page >

  • Python interview questions

    - by Andy
    I am going to interview within two weeks for an internship that would involve Python programming. Can anyone suggest what possible areas should I polish? I am looking for commonly asked stuff in interviews for Python openings. Apart from the fact that I have already been doing the language for over a year now, I fail to perceive what they can ask me. Like for a C or C++ interview, there are lots of questions ranging from reversing of strings to building linked lists, but for a Python interview, I am clueless. Personal experiences and/ or suggestions are welcomed.

    Read the article

  • Correct For Loop Design

    - by Yttrill
    What is the correct design for a for loop? Felix currently uses if len a > 0 do for var i in 0 upto len a - 1 do println a.[i]; done done which is inclusive of the upper bound. This is necessary to support the full range of values of a typical integer type. However the for loop shown does not support zero length arrays, hence the special test, nor will the subtraction of 1 work convincingly if the length of the array is equal to the number of integers. (I say convincingly because it may be that 0 - 1 = maxval: this is true in C for unsigned int, but are you sure it is true for unsigned char without thinking carefully about integral promotions?) The actual implementation of the for loop by my compiler does correctly handle 0 but this requires two tests to implement the loop: continue: if not (i <= bound) goto break body if i == bound goto break ++i goto continue break: Throw in the hand coded zero check in the array example and three tests are needed. If the loop were exclusive it would handle zero properly, avoiding the special test, but there'd be no way to express the upper bound of an array with maximum size. Note the C way of doing this: for(i=0; predicate(i); increment(i)) has the same problem. The predicate is tested after the increment, but the terminating increment is not universally valid! There is a general argument that a simple exclusive loop is enough: promote the index to a large type to prevent overflow, and assume no one will ever loop to the maximum value of this type.. but I'm not entirely convinced: if you promoted to C's size_t and looped from the second largest value to the largest you'd get an infinite loop!

    Read the article

  • Dependency Injection/IoC container practices when writing frameworks

    - by Dave Hillier
    I've used various IoC containers (Castle.Windsor, Autofac, MEF, etc) for .Net in a number of projects. I have found they tend to encourage a number of bad practices. Are there any established practices for IoC container use, particularly when providing a platform/framework? My aim as a framework writer is to make code as simple and as easy to use as possible. I'd rather write one line of code to construct an object than ten or even just two. For example, a couple of code smells that I've noticed and don't have good suggestions to: Large number of parameters (5) for constructors. Creating services tends to be complex; all of the dependencies are injected via the constructor - despite the fact that the components are rarely optional (except for maybe in testing). Lack of private and internal classes; this one may be a specific limitation of using C# and Silverlight, but I'm interested in how it is solved. It's difficult to tell what a frameworks interface is if all the classes are public; it allows me access to private parts that I probably shouldnt touch. Coupling the object lifecycle to the IoC container. It is often difficult to manually construct the dependencies required to create objects. Object lifecycle is too often managed by the IoC framework. I've seen projects where most classes are registered as Singletons. You get a lack of explicit control and are also forced to manage the internals (it relates to the above point, all classes are public and you have to inject them). For example, .Net framework has many static methods. such as, DateTime.UtcNow. Many times I have seen this wrapped and injected as a construction parameter. Depending on concrete implementation makes my code hard to test. Injecting a dependency makes my code hard to use - particularly if the class has many parameters. How do I provide both a testable interface, as well as one that is easy to use? What are the best practices?

    Read the article

  • Are C++ templates just a kind of glorified macros?

    - by Gulshan
    From different comparisons among C++ templates and C#/Java generics like this one- http://stackoverflow.com/questions/31693/what-are-the-differences-between-generics-in-c-and-java-and-templates-in-c/31929#31929 I have a got a perception that, C++ templates are implemented by some kind of preprocessing, not compiling. In other words, they are just a kind of C macros. Is this right? Then I felt that, if C++ templates are implemented by preprocessing, dynamic linking(.dll) cannot be used. A quick google search also supports this. And lastly, how can we use macros in C to deliver C++ templates like functionalities? Another thing came in my mind about templates similar to some kind of preprocessor that, there can be integers passed as arguments to some templates. And it even supports kind of recursion. But the recursion is not in the assembly/machine code. So, am I wrong calling templates glorified macros? Unlike normal macros, it has some superior abilities. But isn't it a kind of preprocessing?

    Read the article

  • What should we tell our unsupported IE6 users?

    - by Dan Fabulich
    In the upcoming version of our web app, we've broken IE6, and we don't intend to fix it. We've had a clear warning posted for IE6 users for some months; we've decided it's time not to support it. My question is: how should we communicate this to our users? Some people here feel that we should block IE6 users who would try to access the web app, because it's not going to work for them. Others feel that we should just leave up a warning, saying "This doesn't work in IE6," but not block them; instead, if they click to dismiss the warning, just let them in to the broken site to see for themselves that it doesn't work. Who is right? Is there a better way?

    Read the article

  • Should a programmer know Linux ?

    - by Maxtor
    I'm a PHP/Python programmer learning Java and C#(.NET). My main OS is windows 7 but I've used Linux and currently dual-booting with Ubuntu. My Linux knowledge however, is pretty limited. I can work with the command line on simple tasks but that's pretty much it. I don't do any shell scripting, don't know very well the most important commands, nor the system in general. My interests are web development, mobile apps and maybe some embedded stuff in the future. Should I get myself familiarized more with Linux ? Even if at the moment I'm not that interested in it? Is it a must for future job positions considering my field of interest? Thank you.

    Read the article

  • Load Balancer impact on web development

    - by confusedGeek
    This question has it's roots in a SharePoint site that I am help with. Background on the issue I dealt with: The dev box and integration server are not setup behind a load balancer. The links were being built using the HttpRequest.Url value from the current context. Note that the links weren't relative links but full URIs. Once we deployed to testing (which has a LB, amongst other things) we received errors on the links being built since the server had an address of "http://some.site.org:999" while the address at the LB as "https://site.org" (SSL was off-loaded at the LB). The fix was easy enough by using relative URIs. The Question: Since this is the first site I've worked with that's behind a Load Balancer on I'm wondering if there are other gotcha's that I need to consider when developing a site behind one?

    Read the article

  • So what *did* Alan Kay really mean by the term "object-oriented"?

    - by Charlie Flowers
    Reportedly, Alan Kay is the inventor of the term "object oriented". And he is often quoted as having said that what we call OO today is not what he meant. For example, I just found this on Google: I made up the term 'object-oriented', and I can tell you I didn't have C++ in mind -- Alan Kay, OOPSLA '97 I vaguely remember hearing something pretty insightful about what he did mean. Something along the lines of "message passing". Do you know what he meant? Can you fill in more details of what he meant and how it differs from today's common OO? Please share some references if you have any. Thanks.

    Read the article

  • When using method chaining, do I reuse the object or create one?

    - by MainMa
    When using method chaining like: var car = new Car().OfBrand(Brand.Ford).OfModel(12345).PaintedIn(Color.Silver).Create(); there may be two approaches: Reuse the same object, like this: public Car PaintedIn(Color color) { this.Color = color; return this; } Create a new object of type Car at every step, like this: public Car PaintedIn(Color color) { var car = new Car(this); // Clone the current object. car.Color = color; // Assign the values to the clone, not the original object. return car; } Is the first one wrong or it's rather a personal choice of the developer? I believe that he first approach may quickly cause the intuitive/misleading code. Example: // Create a car with neither color, nor model. var mercedes = new Car().OfBrand(Brand.MercedesBenz).PaintedIn(NeutralColor); // Create several cars based on the neutral car. var yellowCar = mercedes.PaintedIn(Color.Yellow).Create(); var specificModel = mercedes.OfModel(99).Create(); // Would `specificModel` car be yellow or of neutral color? How would you guess that if // `yellowCar` were in a separate method called somewhere else in code? Any thoughts?

    Read the article

  • Where to Perform Authentication in REST API Server?

    - by David V
    I am working on a set of REST APIs that needs to be secured so that only authenticated calls will be performed. There will be multiple web apps to service these APIs. Is there a best-practice approach as to where the authentication should occur? I have thought of two possible places. Have each web app perform the authentication by using a shared authentication service. This seems to be in line with tools like Spring Security, which is configured at the web app level. Protect each web app with a "gateway" for security. In this approach, the web app never receives unauthenticated calls. This seems to be the approach of Apache HTTP Server Authentication. With this approach, would you use Apache or nginx to protect it, or something else in between Apache/nginx and your web app? For additional reference, the authentication is similar to services like AWS that have a non-secret identifier combined with a shared secret key. I am also considering using HMAC. Also, we are writing the web services in Java using Spring. Update: To clarify, each request needs to be authenticated with the identifier and secret key. This is similar to how AWS REST requests work.

    Read the article

  • Any tips for designing the invoicing/payment system of a SaaS?

    - by Alexandru Trandafir Catalin
    The SaaS is for real estate companies, and they can pay a monthly fee that will offer them 1000 publications but they can also consume additional publications or other services that will appear on their bill as extras. On registration the user can choose one of the 5 available plans that the only difference will be the quantity of publications their plan allows them to make. But they can pass that limit if they wish, and additional payment will be required on the next bill. A publication means: Publishing a property during one day, for 1 whole month would be: 30 publications. And 5 properties during one day would be 5 publications. So basically the user can: Make publications (already paid in the monthly fee, extra payment only if it passes the limit) Highlight that publication (extra payment) Publish on other websites or printed catalogues (extra payment) Doubts: How to handle modifications in pricing plans? Let's say quantities change, or you want to offer some free stuff. How to handle unpaid invoices? I mean, freeze the service until the payment has been done and then resume it. When to make the invoices? The idea is to make one invoice for the monthly fee and a second invoice for the extra services that were consumed. What payment methods to use? The choosen now is by bank account, and mobile phone validation with a SMS. If user doesn't pay we call that phone and ask for payment. Any examples on billing online services will be welcome! Thanks!

    Read the article

  • Does TDD really work for complex projects?

    - by Amir Rezaei
    I’m asking this question regarding problems I have experienced during TDD projects. I have noticed the following challenges when creating unit tests. Generating and maintaining mock data It’s hard and unrealistic to maintain large mock data. It’s is even harder when database structure undergoes changes. Testing GUI Even with MVVM and ability to test GUI, it takes a lot of code to reproduce the GUI scenario. Testing the business I have experience that TDD works well if you limit it to simple business logic. However complex business logic is hard to test since the number of combinations of tests (test space) is very large. Contradiction in requirements In reality it’s hard to capture all requirements under analysis and design. Many times one note requirements lead to contradiction because the project is complex. The contradiction is found late under implementation phase. TDD requires that requirements are 100% correct. In such cases one could expect that conflicting requirements would be captured during creating of tests. But the problem is that this isn’t the case in complex scenarios. I have read this question: Why does TDD work? Does TDD really work for complex enterprise projects, or is it practically limit to project type?

    Read the article

  • Why are some seasoned ASP.NET developers defecting to Ruby on Rails?

    - by Tony_Henrich
    Once a while I hear some known ASP.NET developer declaring that they quit developing in .NET and moving to Ruby using Ruby in Rails. The problem is they don't mention exactly the reasons. They use words like RoR is 'easier', 'better' & 'faster'. That really doesn't say much to me. Anyone care to do faithful comparison using code samples, case studies ..etc or from personal experience in using both? Try to convince me to throw away all my years of learning C#, the .NET Framework using a powerful IDE (Visual Studio). Does RoR save you hours a week in development time? What are the major pain points in .NET that compels one to move away from it? This question is NOT about a pure RoR vs ASP.NET (MVC) comparison. It's about the compelling technical reasons (getting bored does not count!) to switch over after using a platform for several years and start with a new language and platform. (prefer this to be a wiki)

    Read the article

  • Can a loosely typed language be considered true object oriented?

    - by user61852
    Can a loosely typed programming language like PHP be really considered object oriented? I mean, the methods don't have returning types and method parameters has no declared type either. Doesn't class design require methods to have a return type? Don't methods signatures have specifically-typed parameters? How can OOP techniques help you code in PHP if you always have to check the types of parameters received because the language doesn't enforce types? Please, if I'm wrong, explain it to me. When you design things using UML, then code classes in PHP with no return-typed methods and no-type parameters... Is the code really compliant with the UML design? You spend time designing the architecture of your software, then the compiler doesn't force the programmer to follow your design while coding, letting he/she assign any object variable to any other variable with no "type-mismatch" warning.

    Read the article

  • Should I swap from WCF to NserviceBus

    - by Matt Roberts
    We have a central server that sends and recieves messages from a number of PCs that are located on client networks in various locations. To facilitate this, currently I'm using WCF with TCPNetBindings, using duplex communication secured with certificates. Now, we have a number of issues with this - mainly that we are being asked to support "disconnected mode" (we need to be fault tolerant). From what I know, there is no simple way to do this using the WCF stack - we'd need to implement something and perhaps use msmq. I've been looking at NServiceBus lately, and from I can see it seems to fit the bill well - fault tolerance, messages can be sent over the internet via a simple http gateway, etc. I know it's well respected in the community, and I can see why from looking into it. So, my question is...Does employing NServiceBus sound like a sensible idea, or does anyone have any other suggestions / real world experience that relate to this? I guess I'm worried of introducing a new tech that I know relatively little about, and facing problems with things like securing it, setting everything up in a reliable way, gotchas along the way.. I'm also wary of "gold-plating" the architecture, and choosing something shiny that will end up bogging me down in implementation versus sticking with WCF and just making it work for me.. Thanks!

    Read the article

  • Which paradigm to use for writing chess engine?

    - by poke
    If you were going to write a chess game engine, what programming paradigm would you use (OOP, procedural, etc) and why whould you choose it ? By chess engine, I mean the portion of a program that evaluates the current board and decides the computer's next move. I'm asking because I thought it might be fun to write a chess engine. Then it occured to me that I could use it as a project for learning functional programming. Then it occured to me that some problems aren't well suited to the functional paradigm. Then it occured to me that this might be good discussion fodder.

    Read the article

  • Good approach for hundreds of comsumers and big files

    - by ????? ???????
    I have several files (nearly 1GB each) with data. Data is a string line. I need to process each of these files with several hundreds of consumers. Each of these consumers does some processing that differs from others. Consumers do not write anywhere concurrently. They only need input string. After processing they update their local buffers. Consumers can easily be executed in parallel. Important: With one specific file each consumer has to process all lines (without skipping) in correct order (as they appear in file). The order of processing different files doesn't matter. Processing of a single line by one consumer is comparably fast. I expect less than 50 microseconds on Corei5. So now I'm looking for the good approach to this problem. This is going to be be a part of a .NET project, so please let's stick with .NET only (C# is preferable). I know about TPL and DataFlow. I guess that the most relevant would be BroadcastBlock. But i think that the problem here is that with each line I'll have to wait for all consumers to finish in order to post the new one. I guess that it would be not very efficient. I think that ideally situation would be something like this: One thread reads from file and writes to the buffer. Each consumer, when it is ready, reads the line from the buffer concurrently and processes it. The entry from the buffer shouldn't be deleted as one consumer reads it. It can be deleted only when all consumers have processed it. TPL schedules consumer threads itself. If one consumer outperforms the others, it shouldn't wait and can read more recent entries from the buffer. Am i right with this kind of approach? Whether yes or not, how can i implement the good solution? A bit was already discussed on StackOverflow: link

    Read the article

  • What happened to VM based deployments?

    - by user128670
    Watched some MountainWest RubyConf 2014 talks and noticed an interesting theme. Many dynamic programming environments back in the old days used to be self-contained VM images, e.g. SmallTalk, GemStone/S. One could checkpoint, modify, and ship these images wholesale and have it up and running with very little effort. Fast forward to now and I'm still using Make files to configure and install binaries. What happened?

    Read the article

  • How does key-based caching work?

    - by Dominic Santos
    I recently read an article on the 37Signals blog and I'm left wondering how it is that they get the cache key. It's all well and good having a cache key that includes the object's timestamp (this means that when you update the object the cache will be invalidated); but how do you then use the cache key in a template without causing a DB hit for the very object that you are trying to fetch from the cache. Specifically, how does this affect One to Many relations where you are rendering a Post's Comments for example. Example in Django: {% for comment in post.comments.all %} {% cache comment.pk comment.modified %} <p>{{ post.body }}</p> {% endcache %} {% endfor %} Is caching in Rails different to just requests to memcached for example (I know that they convert your cache key to something different). Do they also cache the cache key?

    Read the article

  • Voice echo in UDP based voice transmission [closed]

    - by Meherzad
    I have coded a java application for voice transmission between to ip in LAN. Here the code. public static Boolean flag= true; public static Boolean recFlag=true; DatagramSocket UDPSocket=null; AudioFormat format = null; TargetDataLine microphone=null; byte[] buffer=null; DatagramPacket UDPPacket=null; public void startChat(String ipAddress){ try{ buffer = new byte[1000]; UDPSocket=new DatagramSocket(1987); Thread th=new Thread(new Listener()); th.start(); microphone = AudioSystem.getTargetDataLine(format); format= new AudioFormat(8000.0f, 16, 1, true, true); UDPPacket = new DatagramPacket(buffer, buffer.length, InetAddress.getByName(ipAddress), 1988); microphone.open(format); microphone.start(); while (flag) { microphone.read(buffer, 0, buffer.length); UDPSocket.send(UDPPacket); } } catch(Exception e){ System.out.println(" ssss "+e.getMessage()); } } public class Listener extends Thread{ byte[] buff=new byte[1000]; DatagramSocket UDPSocket1=null; DatagramPacket recPacket=null; DataLine.Info info = new DataLine.Info(SourceDataLine.class, format); SourceDataLine line=null; @Override public void run(){ try{ UDPSocket1=new DatagramSocket(1988); format= new AudioFormat(8000.0f, 16, 1, true, true); line = (SourceDataLine) AudioSystem.getLine(info); line.open(format); line.start(); } catch(Exception e){ System.out.println("list "+ e.getMessage()); } recPacket=new DatagramPacket(buff, buff.length); while(recFlag){ try{ UDPSocket1.receive(recPacket); buff = (byte[])recPacket.getData(); line.write(buff, 0, buff.length); } catch(Exception e){ System.out.println("errr "+e.getMessage()); } } line.drain(); line.close(); } } Main problem which I am facing that I am getting only echo of my own voice. I am unable to hear voice from the other end only I am hearing is my own voice. Please suggest any solution.

    Read the article

  • As a solo programmer, of what use can Gerrit be?

    - by s.d
    Disclaimer: I'm aware of the questions How do I review my own code? and What advantages do continuous integration tools offer on a solo project?. I do feel that this question aims at a different set of answers though, as it is about a specific software, and not about general musings about the use of this or that practice or tech stack. I'm a solo programmer for an Eclipse RCP-based project. To be able to control myself and the quality of my software, I'm in the process of setting up a CSI stack. In this, I follow the Eclipse Common Build Infrastructure guidelines, with the exception that I will use Jenkins rather than Hudson. Sticking to these guidelines will hopefully help me in getting used to the Eclipse way of doing things, and I hope to be able to contribute some code to Eclipse in the future. However, CBI includes Gerrit, a code review software. While I think it's really helpful for teams, and I will employ it as soon as the team grows to at least two developers, I'm wondering how I could use it while I'm still solo. Question: Is there a use case for Gerrit that takes into account solo developers? Notes: I can imagine reviewing code myself after a certain amount of time to gain a little distance to it. This does complicate the workflow though, as code will only be built once it's been passed through code review. This might prove to be a "trap" as I might be tempted to quickly push bad code through Gerrit just to get it built. I'm very interested in hearing how other solo devs have made use of Gerrit.

    Read the article

  • How can I read data from a generated pointcloud, but from an other perspective of the camera? [migrated]

    - by Vlad Lata
    Basically what I'm trying to do is as follows: I have a software that generates and shows a pointcloud by analyzing Time-of-Flight data (Z-Data). This software has a GUI that delivers this pointcloud on a grid, and you can watch it and adjust the camera to change the perspective, or apply filtering to it and so on. Since the Z-data was recorder through a stereoscopic system, I want to obtain a perspective transformation. My idea was to simply change the position of the camera in the GUI and than add a button that sais (ex. New Perspective) that calls a function that would measure the distances from the existing pointcloud to the camera I'm viewing it from. Of course this would generate some occluded areas, but I want this to happen. And now the main question is: How can I do that? Are there any functions in OpenGL that measure the distance from an object to a camera, or is it even possible to do something like his? Or has someone some other idea? P.S. The software uses the qt sdk and opengl

    Read the article

  • What Web Technology to use for web app?

    - by Chris
    Want to get the opinions of the people of Stack Overflow. I am creating a web application that ideally will have some sort of desktop notification. i would love to do this in HTML5 but cant as need it to run on IE 8 and below. I have looked a Flex but I'm not 100% sure how to achieve desktop notifications when running as a web app. Has anyone had this dilemma or even know of anything that would be the best fit? All opinions are welcome, will help me out a lot

    Read the article

  • Models, controllers, and code reuse

    - by user11715
    I have a blog where users can post comments. When creating a comment, various things happen: creating the comment object, associations, persisting sending notification emails to post's author given his preferences sending notification to moderators given their preferences updating a fulltext database for search ... I could put all this in the controller, but what if I want to reuse this code ? e.g. I would like to provide an API for posting comments. I could also put this in the model, but I wonder if I won't lose flexibility by doing so. And would it be acceptable to do all of this from the model layer ? What would you do ?

    Read the article

  • What have you learnt that has a steep learning curve?

    - by Jonathan Khoo
    Recently, I've invested time in learning the intricacies of Git and it has got me thinking about time and learning. (My previous experience with version control systems was only limited use of CVS and SVN.) It took me a whole day's worth of reading to be able to understand the concepts and differences of Git. There are an infinite number of things available for us to learn. Some, more useful than others. I don't know Fortran - I'm relatively young. But looking back at the preceding years of my life, I notice that I'm busier and busier as time goes on. The amount of things I have to get through in a day is increasingly out of my control. It doesn't take a genius to extrapolate that information and realise I'll have even less time in the future - unless I get fired, but I have no strong plans relating to that idea for now. So, given that I have much more time and energy now than I will have in the future: what have you learnt, that has a steep learning curve, that you would possibly recommend to a fellow programmer? Edit: I've stumbled upon the excellent question What programming skills have provided you the best return on investment? and hav realised that my way of approaching how to spend learning time was naive - it doesn't matter if ten useful concepts can be learnt in the time of one if they're worth it.

    Read the article

< Previous Page | 98 99 100 101 102 103 104 105 106 107 108 109  | Next Page >