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  • A programmer who doesn't get to program - where to turn? [closed]

    - by Just an Anon
    I'm in my mid 20's, and have been working as a full time programmer / developer for the last ~6 years, with several years of part-time freelancing before this, and three straight years of freelancing in the middle of this short career. I work mostly with PHP and the Drupal framework. By and large, I focus on programming custom pieces of functionality; these, of course, vary greatly from project to project. I've got years of solid experience with OOP (have done some Java & C# years ago, too) including intensive experience with front-end development, and even some design work. I've lead small teams (2-4 people) of developers. And of course, given the large amount of freelancing, I've got decent project- & client-management skills. My problem is staying motivated at any place of employment. In the time mentioned I've worked (full-time) at six local companies. The longest I've stayed at any company was just over a year. I find that I'll get hired and be very excited and motivated for the first few months, but the work quickly gets "stale." By that I mean that the interesting components (ie. the programming) get done, and the rest of the work turns into boring cleanup (move a button, add text, change colours, add a field). I don't get challenged, and I don't feel like I'm learning anything new. This happens repeatedly time and time again, and I always end up leaving for either a new opportunity, or to freelance. I'm wondering if perhaps I've painted myself into a corner with the rather niche work market (although with very high demand and good compensation) and need to explore other career choices. Another possibility is that I may be choosing the wrong places of employment, mostly small agencies, and need to look into working for a larger, more established firm. I find programming, writing code, and architecting solutions very rewarding. When I'm working on an interesting problem I lose all sense of time and 14-16 hours can fly by like minutes. I get the same exciting feeling when I'm doing high-level planning of a complex system, breaking up the work and figuring out how everything will tie-in together. I absolutely hate doing small, "stupid" changes that pose no challenge, yet seem to make up more and more of my work. I want to find a workplace where I will get to work on such tasks, be challenged, and improve in all areas of product development. This maybe a programming job, management, architecture of desktop apps, or may be managing a taco stand on a beach in Mexico - I don't know, and I need some advice and real-world feedback. What are some job areas worth exploring? The requirements are fairly simple: working with computers interacting with others challenging decent pay (I'm making just short of 90k / year with a month of vacation & some benefits, and would like to stay in this range, but am willing to take a temporary cut in pay for a more interesting position) Any advice would be much appreciated!

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  • Why is 0 false?

    - by Morwenn
    This question may sound dumb, but why does 0 evaluates to false and any other [integer] value to true is most of programming languages? String comparison Since the question seems a little bit too simple, I will explain myself a little bit more: first of all, it may seem evident to any programmer, but why wouldn't there be a programming language - there may actually be, but not any I used - where 0 evaluates to true and all the other [integer] values to false? That one remark may seem random, but I have a few examples where it may have been a good idea. First of all, let's take the example of strings three-way comparison, I will take C's strcmp as example: any programmer trying C as his first language may be tempted to write the following code: if (strcmp(str1, str2)) { // Do something... } Since strcmp returns 0 which evaluates to false when the strings are equal, what the beginning programmer tried to do fails miserably and he generally does not understand why at first. Had 0 evaluated to true instead, this function could have been used in its most simple expression - the one above - when comparing for equality, and the proper checks for -1 and 1 would have been done only when needed. We would have considered the return type as bool (in our minds I mean) most of the time. Moreover, let's introduce a new type, sign, that just takes values -1, 0 and 1. That can be pretty handy. Imagine there is a spaceship operator in C++ and we want it for std::string (well, there already is the compare function, but spaceship operator is more fun). The declaration would currently be the following one: sign operator<=>(const std::string& lhs, const std::string& rhs); Had 0 been evaluated to true, the spaceship operator wouldn't even exist, and we could have declared operator== that way: sign operator==(const std::string& lhs, const std::string& rhs); This operator== would have handled three-way comparison at once, and could still be used to perform the following check while still being able to check which string is lexicographically superior to the other when needed: if (str1 == str2) { // Do something... } Old errors handling We now have exceptions, so this part only applies to the old languages where no such thing exist (C for example). If we look at C's standard library (and POSIX one too), we can see for sure that maaaaany functions return 0 when successful and any integer otherwise. I have sadly seen some people do this kind of things: #define TRUE 0 // ... if (some_function() == TRUE) { // Here, TRUE would mean success... // Do something } If we think about how we think in programming, we often have the following reasoning pattern: Do something Did it work? Yes -> That's ok, one case to handle No -> Why? Many cases to handle If we think about it again, it would have made sense to put the only neutral value, 0, to yes (and that's how C's functions work), while all the other values can be there to solve the many cases of the no. However, in all the programming languages I know (except maybe some experimental esotheric languages), that yes evaluates to false in an if condition, while all the no cases evaluate to true. There are many situations when "it works" represents one case while "it does not work" represents many probable causes. If we think about it that way, having 0 evaluate to true and the rest to false would have made much more sense. Conclusion My conclusion is essentially my original question: why did we design languages where 0 is false and the other values are true, taking in account my few examples above and maybe some more I did not think of? Follow-up: It's nice to see there are many answers with many ideas and as many possible reasons for it to be like that. I love how passionate you seem to be about it. I originaly asked this question out of boredom, but since you seem so passionate, I decided to go a little further and ask about the rationale behind the Boolean choice for 0 and 1 on Math.SE :)

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  • Best ways to teach a beginner to program?

    - by Justin Standard
    Original Question I am currently engaged in teaching my brother to program. He is a total beginner, but very smart. (And he actually wants to learn). I've noticed that some of our sessions have gotten bogged down in minor details, and I don't feel I've been very organized. (But the answers to this post have helped a lot.) What can I do better to teach him effectively? Is there a logical order that I can use to run through concept by concept? Are there complexities I should avoid till later? The language we are working with is Python, but advice in any language is welcome. How to Help If you have good ones please add the following in your answer: Beginner Exercises and Project Ideas Resources for teaching beginners Screencasts / blog posts / free e-books Print books that are good for beginners Please describe the resource with a link to it so I can take a look. I want everyone to know that I have definitely been using some of these ideas. Your submissions will be aggregated in this post. Online Resources for teaching beginners: A Gentle Introduction to Programming Using Python How to Think Like a Computer Scientist Alice: a 3d program for beginners Scratch (A system to develop programming skills) How To Design Programs Structure and Interpretation of Computer Programs Learn To Program Robert Read's How To Be a Programmer Microsoft XNA Spawning the Next Generation of Hackers COMP1917 Higher Computing lectures by Richard Buckland (requires iTunes) Dive into Python Python Wikibook Project Euler - sample problems (mostly mathematical) pygame - an easy python library for creating games Create Your Own Games With Python ebook Foundations of Programming for a next step beyond basics. Squeak by Example Recommended Print Books for teaching beginners Accelerated C++ Python Programming for the Absolute Beginner Code by Charles Petzold

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  • Are there code signing certificates cheaper than US$99 per year? [closed]

    - by gerryLowry
    K Software discounts Comodo code signing certificates to US$99 per year. In the past, I've seen Commodo code signing certificates for US$80. I'm excluding CAcert which AFAIK are FREE but are not covered by browsers like Internet Explorer AFAIK. QUESTION: What is the best price per year for a code signing certificate? Thank you ~~ gerry (lowry) Edit: **THIS SHOULD NOT HAVE BEEN CLOSED** from the FAQ: http://stackoverflow.com/faq ---------------------------- What kind of questions can I ask here? Programming questions, of course! As long as your question is: * detailed and specific <====== YES! * written clearly and simply <====== YES! * of interest to other programmers <====== YES! I've been programming for over 40 years. http://gerrylowryprogrammer.com/ I've taught computer programming at the community college level. I'm a Star level contributer to forums.asp.net. http://forums.asp.net/members/gerrylowry.aspx IMO, I've a very good idea what is of interest to other programmers. MORE INFORMATION http://en.wikipedia.org/wiki/Code_signing http://msdn.microsoft.com/en-us/library/ms537361%28VS.85%29.aspx also: via Google: code signing Ensuring the integrity of code and executables that one distributes is just as much about programming as is knowing how to flip bits in assembler, use delegates in C#, and use the BDD context/specification still of "test first testing".

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  • Getting SSL to work with Apache/Passenger on OSX

    - by jonnii
    I use apache/passenger on my development machine, but need to add SSL support (something which isn't exposed through the control panel). I've done this before in production, but for some reason I can't seem to get it work on OSX. The steps I've followed so far are from a default apache osx install: Install passenger and passenger preference pane. Add my rails app (this works) Create my ca.key, server.crt and server.key as detailed on the apple website. At this point I need to start editing the apache configs, so I added: # Apache knows to listen on port 443 for ssl requests. Listen 443 Listen 80 I thought I'd try editing the passenger pref pane generated config first to get everything working, when I add: It starts off looking like this <VirtualHost *:80> ServerName myapp.local DocumentRoot "/Users/jonnii/programming/ruby/myapp/public" RailsEnv development <Directory "/Users/jonnii/programming/ruby/myapp/public"> Order allow,deny Allow from all </Directory> </VirtualHost> I then append this: <VirtualHost *:443> ServerName myapp.local DocumentRoot "/Users/jonnii/programming/ruby/myapp/public" RailsEnv development <directory "/Users/jonnii/programming/ruby/myapp/public"> Order allow,deny Allow from all </directory> # SSL Configuration SSLEngine on SSLCipherSuite ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP SSLOptions +FakeBasicAuth +ExportCertData +StdEnvVars +StrictRequire #Self Signed certificates SSLCertificateFile /private/etc/apache2/ssl.key/server.crt SSLCertificateKeyFile /private/etc/apache2/ssl.key/server.key SSLCertificateChainFile /private/etc/apache2/ssl.key/ca.crt SetEnvIf User-Agent ".*MSIE.*" nokeepalive ssl-unclean-shutdown downgrade-1.0 force-response-1.0 </VirtualHost> The files referenced all exist (I doubled checked that), but now when I restart my apache I can't even get to myapp.local. However apache can still server the default page when I click on it in the sharing preference panel. Any help would be greatly appreciated.

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  • are there code signing certificates cheaper than US $99 per year? [closed]

    - by gerryLowry
    ksoftware discounts Commodo code signing certificates to US $99 per year. in the past, I've seen Commodo code signing certificates for US $80. I'm excluding CAcert which AFAIK are FREE but are not covered by browsers like IE AFAIK. QUESTION: What is the best price per year for a code signing certificate? Thank you ~~ gerry (lowry) Edit: **THIS SHOULD NOT HAVE BEEN CLOSED** from the FAQ: http://stackoverflow.com/faq ---------------------------- What kind of questions can I ask here? Programming questions, of course! As long as your question is: * detailed and specific <====== YES! * written clearly and simply <====== YES! * of interest to other programmers <====== YES! I've been programming for over 40 years. http://gerrylowryprogrammer.com/ I've taught computer programming at the community college level. I'm a Star level contributer to forums.asp.net. http://forums.asp.net/members/gerrylowry.aspx imo, I've a very good idea what is of interest to other programmers. MORE INFORMATION Ensuring the integrity of code and executables that one distributes is just as much about programming as is knowing how to flip bits in assembler, use delegates in c#, and use the BDD context/specification still of "test first testing".

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  • Writing fortran robust and "modern" code

    - by Blklight
    In some scientific environments, you often cannot go without FORTRAN as most of the developers only know that idiom, and there is lot of legacy code and related experience. And frankly, there are not many other cross-platform options for high performance programming ( C++ would do the task, but the syntax, zero-starting arrays, and pointers are too much for most engineers ;-) ). I'm a C++ guy but I'm stuck with some F90 projects. So, let's assume a new project must use FORTRAN (F90), but I want to build the most modern software architecture out of it. while being compatible with most "recent" compilers (intel ifort, but also including sun/HP/IBM own compilers) So I'm thinking of imposing: global variable forbidden, no gotos, no jump labels, "implicit none", etc. "object-oriented programming" (modules with datatypes + related subroutines) modular/reusable functions, well documented, reusable libraries assertions/preconditions/invariants (implemented using preprocessor statements) unit tests for all (most) subroutines and "objects" an intense "debug mode" (#ifdef DEBUG) with more checks and all possible Intel compiler checks possible (array bounds, subroutine interfaces, etc.) uniform and enforced legible coding style, using code processing tools C stubs/wrappers for libpthread, libDL (and eventually GPU kernels, etc.) C/C++ implementation of utility functions (strings, file operations, sockets, memory alloc/dealloc reference counting for debug mode, etc.) ( This may all seem "evident" modern programming assumptions, but in a legacy fortran world, most of these are big changes in the typical programmer workflow ) The goal with all that is to have trustworthy, maintainable and modular code. Whereas, in typical fortran, modularity is often not a primary goal, and code is trustworthy only if the original developer was very clever, and the code was not changed since then ! (i'm a bit joking here, but not much) I searched around for references about object-oriented fortran, programming-by-contract (assertions/preconditions/etc.), and found only ugly and outdated documents, syntaxes and papers done by people with no large-scale project involvement, and dead projects. Any good URL, advice, reference paper/books on the subject?

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  • How to learn how to program?

    - by twinbornJoint
    I would like to know the best methods for learning to program. I've been directed towards the Python language because I was told it is good for beginners. I ultimately want to make games for OS X/iPhone. My problem is that I understand what I read but I can't apply my knowledge to anything. I am a programming noob. Should I stick with Python? (is there a better language I should be learning?) Where can I learn programming theory? I get very hyper when reading my book sometimes, any tips on staying calm and focusing? What are effective ways to learn how to program? Are there standard exercises for programming? (I feel solving problems helps my understanding immensely) Ultimately I feel like I am in a never ending tunnel that leads me no where. It feels like I am just completely unable to pursue anything in the world of programming, yet it is something I want to do very much. Thanks.

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  • How to push further as a programmer?

    - by MaXX
    For the last, hmm, 6 months I've been reading into Programming in C, I got myself K&Rv2, BEEJ's socket guide, Expert C programming, Linux Systems Programming, the ISO/IEC 9899:1999 specification (real, and not draft). After receiving them from Amazon, I got Linux installed, and got to it. I'm done with K&R, about halfway through Expert C Programming, but still feel weak as a programmer, I'm sure it takes much more than 6 months of reading to become truly skilled, but my question is this: I've done all the exercises in K&Rv2 (in chapter 1) and some in other chapters, most of which are generally really boring. How do I lift my skills, and become truly great? I've invested money, time and a general lifestyle for something I truly desire, but I'm not sure how exactly to achieve it. Could someone explain to me, perhaps if I need to continuously code, what exactly I'm to code? I'm pretty sure, coding up hello world programs isn't going to teach me any more than I already know about anything. A friend of mine said "read" (with emphasis on read) a man page a day, but reading is all I do, I want to do, but I'm not sure what! I'm interested in security, but I'm not sure as a novice what to code that would be considered enough. Ah, I hope you don't delete this paste :) Thanks

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  • C++: Conceptual problem in designing an intepreter

    - by sub
    I'm programming an interpreter for an experimental programming language (educational, fun,...) So far, everything went well (Tokenizer & Parser), but I'm getting a huge problem with some of the data structures in the part that actually runs the tokenized and parsed code. My programming language basically has only two types, int and string, and they are represented as C++ strings (std class) and ints Here is a short version of the data structure that I use to pass values around: enum DataType { Null, Int, String } class Symbol { public: string identifier; DataType type; string stringValue; int intValue; } I can't use union because string doesn't allow me to. This structure above is beginning to give me a headache. I have to scatter code like this everywhere in order to make it work, it is beginning to grow unmaintainable: if( mySymbol.type == Int ) { mySymbol.intValue = 1234; } else { mySymbol.stringValue = "abcde"; } I use the Symbol data structure for variables, return values for functions and general representation of values in the programming language. Is there any better way to solve this? I hope so!

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  • The Proper Use of the VM Role in Windows Azure

    - by BuckWoody
    At the Professional Developer’s Conference (PDC) in 2010 we announced an addition to the Computational Roles in Windows Azure, called the VM Role. This new feature allows a great deal of control over the applications you write, but some have confused it with our full infrastructure offering in Windows Hyper-V. There is a proper architecture pattern for both of them. Virtualization Virtualization is the process of taking all of the hardware of a physical computer and replicating it in software alone. This means that a single computer can “host” or run several “virtual” computers. These virtual computers can run anywhere - including at a vendor’s location. Some companies refer to this as Cloud Computing since the hardware is operated and maintained elsewhere. IaaS The more detailed definition of this type of computing is called Infrastructure as a Service (Iaas) since it removes the need for you to maintain hardware at your organization. The operating system, drivers, and all the other software required to run an application are still under your control and your responsibility to license, patch, and scale. Microsoft has an offering in this space called Hyper-V, that runs on the Windows operating system. Combined with a hardware hosting vendor and the System Center software to create and deploy Virtual Machines (a process referred to as provisioning), you can create a Cloud environment with full control over all aspects of the machine, including multiple operating systems if you like. Hosting machines and provisioning them at your own buildings is sometimes called a Private Cloud, and hosting them somewhere else is often called a Public Cloud. State-ful and Stateless Programming This paradigm does not create a new, scalable way of computing. It simply moves the hardware away. The reason is that when you limit the Cloud efforts to a Virtual Machine, you are in effect limiting the computing resources to what that single system can provide. This is because much of the software developed in this environment maintains “state” - and that requires a little explanation. “State-ful programming” means that all parts of the computing environment stay connected to each other throughout a compute cycle. The system expects the memory, CPU, storage and network to remain in the same state from the beginning of the process to the end. You can think of this as a telephone conversation - you expect that the other person picks up the phone, listens to you, and talks back all in a single unit of time. In “Stateless” computing the system is designed to allow the different parts of the code to run independently of each other. You can think of this like an e-mail exchange. You compose an e-mail from your system (it has the state when you’re doing that) and then you walk away for a bit to make some coffee. A few minutes later you click the “send” button (the network has the state) and you go to a meeting. The server receives the message and stores it on a mail program’s database (the mail server has the state now) and continues working on other mail. Finally, the other party logs on to their mail client and reads the mail (the other user has the state) and responds to it and so on. These events might be separated by milliseconds or even days, but the system continues to operate. The entire process doesn’t maintain the state, each component does. This is the exact concept behind coding for Windows Azure. The stateless programming model allows amazing rates of scale, since the message (think of the e-mail) can be broken apart by multiple programs and worked on in parallel (like when the e-mail goes to hundreds of users), and only the order of re-assembling the work is important to consider. For the exact same reason, if the system makes copies of those running programs as Windows Azure does, you have built-in redundancy and recovery. It’s just built into the design. The Difference Between Infrastructure Designs and Platform Designs When you simply take a physical server running software and virtualize it either privately or publicly, you haven’t done anything to allow the code to scale or have recovery. That all has to be handled by adding more code and more Virtual Machines that have a slight lag in maintaining the running state of the system. Add more machines and you get more lag, so the scale is limited. This is the primary limitation with IaaS. It’s also not as easy to deploy these VM’s, and more importantly, you’re often charged on a longer basis to remove them. your agility in IaaS is more limited. Windows Azure is a Platform - meaning that you get objects you can code against. The code you write runs on multiple nodes with multiple copies, and it all works because of the magic of Stateless programming. you don’t worry, or even care, about what is running underneath. It could be Windows (and it is in fact a type of Windows Server), Linux, or anything else - but that' isn’t what you want to manage, monitor, maintain or license. You don’t want to deploy an operating system - you want to deploy an application. You want your code to run, and you don’t care how it does that. Another benefit to PaaS is that you can ask for hundreds or thousands of new nodes of computing power - there’s no provisioning, it just happens. And you can stop using them quicker - and the base code for your application does not have to change to make this happen. Windows Azure Roles and Their Use If you need your code to have a user interface, in Visual Studio you add a Web Role to your project, and if the code needs to do work that doesn’t involve a user interface you can add a Worker Role. They are just containers that act a certain way. I’ll provide more detail on those later. Note: That’s a general description, so it’s not entirely accurate, but it’s accurate enough for this discussion. So now we’re back to that VM Role. Because of the name, some have mistakenly thought that you can take a Virtual Machine running, say Linux, and deploy it to Windows Azure using this Role. But you can’t. That’s not what it is designed for at all. If you do need that kind of deployment, you should look into Hyper-V and System Center to create the Private or Public Infrastructure as a Service. What the VM Role is actually designed to do is to allow you to have a great deal of control over the system where your code will run. Let’s take an example. You’ve heard about Windows Azure, and Platform programming. You’re convinced it’s the right way to code. But you have a lot of things you’ve written in another way at your company. Re-writing all of your code to take advantage of Windows Azure will take a long time. Or perhaps you have a certain version of Apache Web Server that you need for your code to work. In both cases, you think you can (or already have) code the the software to be “Stateless”, you just need more control over the place where the code runs. That’s the place where a VM Role makes sense. Recap Virtualizing servers alone has limitations of scale, availability and recovery. Microsoft’s offering in this area is Hyper-V and System Center, not the VM Role. The VM Role is still used for running Stateless code, just like the Web and Worker Roles, with the exception that it allows you more control over the environment of where that code runs.

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  • Is there a way to map a local drive letter in a Virtual PC Guest O/S to a host drive?

    - by Clay Nichols
    I have a bunch of programming projects on my P:\ drive (on Windows 7) I'm now doing some programming within Virtual PC Windows XP Mode and I'd like to "call" that drive, within the Win XP guest, the P: drive. I've mapped drive letter P: to "network" drive on the Host but that goes across the network so it's very slow. I tried using the SUBST command but it wouldn't take the \tsclients\p as a parameter. Basically, the command line interpreter (is that DOS on Win 7 ??) doesn't recognize that directory (\tsclients\p)

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  • In Windows Virtual PC: Is there a way to assign local drive letter in the Guest O/S that points to a

    - by Clay Nichols
    I have a bunch of programming projects on my P:\ drive (on Windows 7) I'm now doing some programming within Virtual PC Windows XP Mode and I'd like to "call" that drive, within the Win XP guest, the P: drive. I've mapped drive letter P: to "network" drive on the Host but that goes across the network so it's very slow. I tried using the SUBST command but it wouldn't take the \tsclients\p as a parameter. Basically, the command line interpreter (is that DOS on Win 7 ??) doesn't recognize that directory (\tsclients\p)

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  • HashSet vs. List performance

    - by Michael Damatov
    It's clear that a search performance of the generic HashSet<T> class is higher than of the generic List<T> class. Just compare the hash-based key with the linear approach in the List<T> class. However calculating a hash key may itself take some CPU cycles, so for a small amount of items the linear search can be a real alternative to the HashSet<T>. My question: where is the break-even? To simplify the scenario (and to be fair) let's assume that the List<T> class uses the element's Equals() method to identify an item.

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  • How to programatically set drawableLeft on Android button?

    - by Frank LoVecchio
    I'm dynamically creating buttons. I styled them using XML first, and I'm trying to take the XML below and make it programattic. <Button android:id="@+id/buttonIdDoesntMatter" android:layout_height="wrap_content" android:layout_width="fill_parent" android:text="buttonName" android:drawableLeft="@drawable/imageWillChange" android:onClick="listener" android:layout_width="fill_parent"> </Button> This is what I have so far. I can do everything but the drawable. linear = (LinearLayout) findViewById(R.id.LinearView); Button button = new Button(this); button.setText("Button"); button.setOnClickListener(listener); button.setLayoutParams( new LayoutParams( android.view.ViewGroup.LayoutParams.FILL_PARENT, android.view.ViewGroup.LayoutParams.WRAP_CONTENT ) ); linear.addView(button);

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  • Visual C# GUI Designer basic tutorial

    - by cusack
    Hi, can you recommend a Visual C# Form Designer tutorial that is targeted at experienced programmers who have at least a basic knowledge of C# but are new to the VS C# Form Designer. At least it shouldn't be targeted at programming newbs, like Introduction to Visual C# 2008 Express Edition (it explains how a comment looks like in C#). So far I've found C# Programming Tutorial - Programming Winforms in C# on stackoverflow. Wishlist: ;-) I'm more interested in focus on the designer itself rather than an explanation of single gui-elements. In other words explaining separation between generated-code, what to not edit manually (visual-c#-designer-responsibility) and on the other hand the parts for which the programmer himself is responsible. So a little more abstract best-practice point of view pointing out some caveats would be great as well. I would prefer text over video as well, but that's minor. /Wishlist Perhaps even a Microsoft reference specific to the Visual c# forms designer (which I seem to have been unable to find) would be helpful.

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  • I never really understood: what is CGI?

    - by claws
    CGI is a Comman Gateway Interface. As the name says, it is a "common" gateway interface for everything. It is so trivial and naive from the name. I feel that I understood this and I felt this every time I encountered this word. But frankly, I didn't. I'm still confused. I am a PHP programmer. I did lot of web development. user (client) request for page --- webserver(-embedded PHP interpreter) ---- Server side(PHP) Script --- MySQL Server. Now say my PHP Script can fetch results from MySQL Server && MATLAB Server && Some other server. So, now PHP Script is the CGI? because its interface for the between webserver & All other servers? I don't know. Sometimes they call CGI, a technology & othertimes they call CGI a program or someother server. What exactly is CGI? Whats the big deal with /cgi-bin/*.cgi? Whats up with this? I don't know what is this cgi-bin directory on the server for. I don't know why they have *.cgi extensions. Why does Perl always comes in the way. CGI & Perl (language). I also don't know whats up with these two. Almost all the time I keep hearing these two in combination "CGI & Perl". This book is another great example CGI Programming with Perl Why not "CGI Programming with PHP/JSP/ASP". I never saw such things. CGI Programming in C this confuses me a lot. in C?? Seriously?? I don't know what to say. I"m just confused. "in C"?? This changes everything. Program needs to be compiled and executed. This entirely changes my view of web programming. When do I compile? How does the program gets executed (because it will be a machine code, so it must execute as a independent process). How does it communicate with the web server? IPC? and interfacing with all the servers (in my example MATLAB & MySQL) using socket programming? I'm lost!! They say that CGI is depreciated. Its no more in use. Is it so? What is its latest update? Once, I ran into a situation where I had to give HTTP PUT request access to web server (Apache HTTPD). Its a long back. So, as far as I remember this is what I did: Edited the configuration file of Apache HTTPD to tell webserver to pass all HTTP PUT requests to some put.php ( I had to write this PHP script) Implement put.php to handle the request (save the file to the location mentioned) People said that I wrote a CGI Script. Seriously, I didn't have clue what they were talking about. Did I really write CGI Script? I hope you understood what my confusion is. (Because I myself don't know where I'm confused). I request you guys to keep your answer as simple as possible. I really can't understand any fancy technical terminology. At least not in this case. EDIT: I found this amazing tutorial "CGI Programming Is Simple!" - CGI Tutorial Which explains the concepts in simplest possible way. I've only have one complaint about this tutorial. Just to make what ever he explained complete he should have shown the C code he used for generating response for those GET / POST requests. I've also added link to this tutorial to Wikipedia's article : http://en.wikipedia.org/wiki/Common_Gateway_Interface

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  • How do I make matlab legends match the colour of the graphs?

    - by Alex Gosselin
    Here is the code I used: x = linspace(0,2); e = exp(1); lin = e; quad = e-e.*x.*x/2; cub = e-e.*x.*x/2; quart = e-e.*x.*x/2+e.*x.*x.*x.*x/24; act = e.^cos(x); mplot = plot(x,act,x,lin,x,quad,x,cub,x,quart); legend('actual','linear','quadratic','cubic','quartic') This produces a legend matching the right colors to actual and linear, then after that it seems to skip over red on the graph, but not on the legend, i.e. the legend says quadratic should be red, but the graph shows it as green, the legend says cubic should be green, but the graph shows it as purple etc. Any help is appreciated.

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  • Using CSS gradient instead of images

    - by Wiika
    Using CSS for creating gradients instead of images, does it have any negativity? For example the following code: #gradient { color: #fff; height: 100px; padding: 10px; /* For WebKit (Safari, Google Chrome etc) */ background: -webkit-gradient(linear, left top, left bottom, from(#00f), to(#fff)); /* For Mozilla/Gecko (Firefox etc) */ background: -moz-linear-gradient(top, #00f, #fff); /* For Internet Explorer 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.gradient(startColorstr=#FF0000FF, endColorstr=#FFFFFFFF); /* For Internet Explorer 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorstr=#FF0000FF, endColorstr=#FFFFFFFF)"; } Thanks.

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  • What makes you come back to stackoverflow every day? [closed]

    - by rmarimon
    I know this is not a programming question. Let's try to label it a programming community question so that it doesn't get closed. I've been wondering what makes the programming community so prone to helping others in stackoverflow. Is this something particular to programmers? Do you think lawyers and accountants would help other lawyers and programmers as we do? What makes you come back to stackoverflow every day? It would be great to have an answer per reason so that we can get the list of reasons. In my case, I come to stackoverflow to ask questions that I can't solve quickly, and to test how good I am when answering questions. So far I’ve failed miserably at trying to answer questions but it has helped me understand how little I know.

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  • JSON, Ajax login and signup form problem, critique

    - by user552828
    Here is my problem; indexdeneme2.php has two forms Sign up and Login form, and there is validation.js and login.js which are handling the AJAX and JSON response, there are validate.php and login.php which are my scripts for validating and login. When you sign up, it sends the data to validate.php perfectly and validate.php response with JSON perfectly, validate.js must show the error in #error div. validation.js works perfectly if it is working alone. I use same kind of script for login form. Login.php also works perfectly it responses with JSON and login.js shows the errors are appear in #errorlogin div. But this works when login.js works alone. When I try to work login.js and validate.js together, it is not working. validate.php and login.php works perfectly but login.js and validation.js are not working together. They can't handle the responses coming from php scripts. It is not showing the errors in #errorlogin and #error div. They intercept each other I guess. By the way if you can critique my login.php and validate.php I will be really appreciated. Thank you all. this is indexdeneme2.php <?php include('functions.php')?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Untitled Document</title> <link rel="stylesheet" href="css/cssdeneme1.css" /> <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js"></script> <script type="text/javascript" src="validation.js"></script> <script type="text/javascript" src="login.js"></script> <script type="text/javascript"> var RecaptchaOptions = { theme : 'custom', custom_theme_widget: 'recaptcha_widget' }; </script> </head> <body onload="document.signup.reset()"> <div id="topbar"> <div class="wrapper"> </div> </div> <div id="middlebar"> <div class="wrapper"> <div id="middleleft"> <div id="mainformsecondcover"> <div id="mainform"> <div id="formhead"> <div id="signup">Sign Up</div> </div> <form method="post" action="validate.php" id="myform" name="signup"> <div id="form"> <table border="0" cellpadding="0" cellspacing="1"> <tbody> <tr> <td class="formlabel"> <label for="name">First Name:</label> </td> <td class="forminput"> <input type="text" name="name" id="name" /> </td> </tr> <tr> <td class="formlabel"> <label for="lastname">Last Name:</label> </td> <td class="forminput"> <input type="text" name="surname" id="lastname" /> </td> </tr> <tr> <td class="formlabel"> <label for="email">Email:</label> </td> <td class="forminput"> <input type="text" name="email" id="email" /> </td> </tr> <tr> <td class="formlabel"> <label for="remail">Re-Enter Email:</label> </td> <td class="forminput"> <input type="text" name="remail" id="remail" /> </td> </tr> <tr> <td class="formlabel"> <label for="password">Password:</label> </td> <td class="forminput"> <input type="password" name="password" id="password" maxlength="16" /> </td> </tr> <tr> <td class="formlabel"> <label for="gender">I am:</label> </td> <td class="forminput"> <select name="gender" id="gender"> <option value="0" selected="selected">-Select Sex-</option> <option value="1">Male</option> <option value="2">Female</option> </select> </td> </tr> <tr> <td class="formlabel"> <label>My Birthday:</label> </td> <td class="forminput"> <select size="1" name="day"> <option value="0" selected="selected">Day</option> <?php formDay(); ?> </select>&nbsp; <select size="1" name="month"> <option value="0" selected="selected">Month</option> <option value="1">January</option> <option value="2">February</option> <option value="3">March</option> <option value="4">April</option> <option value="5">May</option> <option value="6">June</option> <option value="7">July</option> <option value="8">August</option> <option value="9">September</option> <option value="10">October</option> <option value="11">November</option> <option value="12">December</option> </select>&nbsp; <select size="1" name="year"> <option value="0" selected="selected">Year</option> <?php formYear(); ?> </select> </td> </tr> <tr> <td class="formlabel"> <label for="recaptcha_response_field">Security Check:</label> </td> </tr> </tbody> </table> <?php require_once('captchalib.php'); ?> </div> <div id="formbottom"> <div id="error"> </div> <div id="formbottomright"> <input type="submit" id="formbutton" value="Sign Up" /> <img id="loading" src="css/images/ajax-loader.gif" height="35" width="35" alt="Processing.." style="float:right; display:block" /> </div> </div> </form> </div> </div> </div> <div id="middleright"> <div id="loginform"> <form name="login" action="login.php" method="post" id="login"> <label for="username">Email:</label> <input type="text" name="emaillogin" /> <label for="password">Password:</label> <input type="password" name="passwordlogin" maxlength="16" /> <input type="submit" value="Login" /> <img id="loading2" src="css/images/ajax-loader.gif" height="35" width="35" alt="Processing.." style="float:right; display:block" /> </form> </div> <div id="errorlogin"></div> </div> </div> </div> <div id="bottombar"> <div class="wrapper"></div> </div> </body> </html> validation.js $(document).ready(function(){ $('#myform').submit(function(e) { register(); e.preventDefault(); }); }); function register() { hideshow('loading',1); error(0); $.ajax({ type: "POST", url: "validate.php", data: $('#myform').serialize(), dataType: "json", success: function(msg){ if(parseInt(msg.status)==1) { window.location=msg.txt; } else if(parseInt(msg.status)==0) { error(1,msg.txt); Recaptcha.reload(); } hideshow('loading',0); } }); } function hideshow(el,act) { if(act) $('#'+el).css('visibility','visible'); else $('#'+el).css('visibility','hidden'); } function error(act,txt) { hideshow('error',act); if(txt) $('#error').html(txt); } login.js $(document).ready(function(){ $('#login').submit(function(e) { login(); e.preventDefault(); }); }); function login() { error(2); $.ajax({ type: "POST", url: "login.php", data: $('#login').serialize(), dataType: "json", success: function(msg){ if(parseInt(msg.status)==3) { window.location=msg.txt; } else if(parseInt(msg.status)==2) { error(3,msg.txt); } } }); } function error(act,txt) { hideshow('error',act); if(txt) $('#errorlogin').html(txt); } login.php <?php session_start(); require("connect.php"); $email = $_POST['emaillogin']; $password = $_POST['passwordlogin']; $email = mysql_real_escape_string($email); $password = mysql_real_escape_string($password); if(empty($email)) { die('{status:2,txt:"Enter your email address."}'); } if(!filter_var($email, FILTER_VALIDATE_EMAIL)) { die('{status:2,txt:"Invalid email or password"}'); } if(empty($password)) { die('{status:2,txt:"Enter your password."}'); } if(strlen($password)<6 || strlen($password)>16) { die('{status:2,txt:"Invalid email or password"}'); } $query = "SELECT password, salt FROM users WHERE Email = '$email';"; $result = mysql_query($query); if(mysql_num_rows($result) < 1) //no such user exists { die('{status:2,txt:"Invalid email or password"}'); } $userData = mysql_fetch_array($result, MYSQL_ASSOC); $hash = hash('sha256', $userData['salt'] . hash('sha256', $password) ); if($hash != $userData['password']) //incorrect password { die('{status:2,txt:"Invalid email or password"}'); } //////////////////////////////////////////////////////////////////////////////////// if('{status:3}') { session_regenerate_id (); //this is a security measure $getMemDetails = "SELECT * FROM users WHERE Email = '$email'"; $link = mysql_query($getMemDetails); $member = mysql_fetch_row($link); $_SESSION['valid'] = 1; $_SESSION['userid'] = $member[0]; $_SESSION['name'] = $member[1]; session_write_close(); mysql_close($con); echo '{status:3,txt:"success.php"}'; } validate.php <?php $name = $_POST['name']; $surname = $_POST['surname']; $email = $_POST['email']; $remail = $_POST['remail']; $gender = $_POST['gender']; $bdate = $_POST['year'].'-'.$_POST['month'].'-'.$_POST['day']; $bday = $_POST['day']; $bmon = $_POST['month']; $byear = $_POST['year']; $cdate = date("Y-n-j"); $password = $_POST['password']; $hash = hash('sha256', $password); $regdate = date("Y-m-d"); function createSalt() { $string = md5(uniqid(rand(), true)); return substr($string, 0, 3); } $salt = createSalt(); $hash = hash('sha256', $salt . $hash); if(empty($name) || empty($surname) || empty($email) || empty($remail) || empty($password) ) { die('{status:0,txt:"All the fields are required"}'); } if(!preg_match('/^[A-Za-z\s ]+$/', $name)) { die('{status:0,txt:"Please check your name"}'); } if(!preg_match('/^[A-Za-z\s ]+$/', $surname)) { die('{status:0,txt:"Please check your last name"}'); } if($bdate > $cdate) { die('{status:0,txt:"Please check your birthday"}'); } if(!(int)$gender) { die('{status:0,txt:"You have to select your sex"}'); } if(!(int)$bday || !(int)$bmon || !(int)$byear) { die('{status:0,txt:"You have to fill in your birthday"}'); } if(!$email == $remail) { die('{status:0,txt:"Emails doesn&sbquo;t match"}'); } if(!filter_var($email, FILTER_VALIDATE_EMAIL)) { die('{status:0,txt:"Enter a valid email"}'); } if(strlen($password)<6 || strlen($password)>16) { die('{status:0,txt:"Password must be between 6-16 characters"}'); } if (!$_POST["recaptcha_challenge_field"]===$_POST["recaptcha_response_field"]) { die('{status:0,txt:"You entered incorrect security code"}'); } if('{status:1}') { require("connect.php"); function getRealIpAddr() { if (!empty($_SERVER['HTTP_CLIENT_IP'])) { $ip=$_SERVER['HTTP_CLIENT_IP']; } elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) { $ip=$_SERVER['HTTP_X_FORWARDED_FOR']; } else { $ip=$_SERVER['REMOTE_ADDR']; } return $ip; } $rip = getRealIpAddr(); $ipn = inet_pton($rip); $checkuser = mysql_query("SELECT Email FROM users WHERE Email = '$email'"); $username_exist = mysql_num_rows($checkuser); if ( $username_exist !== 0 ) { mysql_close($con); die('{status:0,txt:"This email Address is already registered!"}'); } else { $query = "INSERT INTO users (name, surname, date, Email, Gender, password, salt, RegistrationDate, IP) VALUES ('$name', '$surname', '$bdate', '$email', '$gender', '$hash', '$salt', '$cdate', '$ipn')"; $link = mysql_query($query); if(!$link) { die('Becerilemedi: ' . mysql_error()); } else { mysql_close($con); echo '{status:1,txt:"afterreg.php"}'; } } } ?> css of indexdeneme2.php * { padding:0; margin:0; } #topbar { width:100%; height:50px; } .wrapper { margin:0 auto; width:1000px; height:100%; } #middlebar { width:100%; height:650px; } #middleleft { width:55%; float:left; height:650px; } #middleright { width:45%; float:right; height:650px; } #mainformsecondcover { width:404px; padding:0px; margin:0px; border:4px solid #59B; border-radius: 14px; -moz-border-radius: 14px; -webkit-border-radius: 14px; } #mainform { width:400px; border:2px solid #CCC; border-radius: 11px; -moz-border-radius: 11px; -webkit-border-radius: 11px; } #formhead { margin:7px; } #signup { margin-top:13px; margin-left:13px; margin-bottom:3px; color:#333; font-size:18px; font-family:"Lucida Sans Unicode", "Lucida Grande", sans-serif; font-weight:bold } #form { margin:7px; } #form table { margin:0px; width:380px; } #form table tr{ height:28px; } #form table td{ height:18px; } .formlabel { cursor:pointer; display:table-cell; text-align:right; font-size:12px; color:#000; font-weight:normal; vertical-align:middle; font-family:"Lucida Sans Unicode", "Lucida Grande", sans-serif; letter-spacing:1px; width:120px; height:37px; padding-right:5px; } .formlabel label{ cursor:pointer } .forminput input { width:240px; font-size:13px; padding:4px; } #recaptcha_image { width:300px; height:57px; border:2px solid #CCC; } #recaptcha_widget { margin-left:35px; } #securityinfo { font-size: 11px; line-height: 16px; } #formbottom { width:360px; min-height:45px; } #error { float:left; width:200px; border:1px solid #F00; margin-left:20px; margin-top:7px; text-align:center; color:#F00; font-family:"Lucida Sans Unicode", "Lucida Grande", sans-serif; font-size:11px; line-height:16px; padding:2px; visibility:hidden; } #errorlogin { float:left; width:200px; border:1px solid #F00; margin-left:20px; margin-top:7px; text-align:center; color:#F00; font-family:"Lucida Sans Unicode", "Lucida Grande", sans-serif; font-size:11px; line-height:16px; padding:2px; visibility:hidden; } #formbottomright { float:right; height:45px; width:115px; margin-left:5px; } #loading { visibility:hidden; } #loading2 { visibility:hidden; } #formbutton { display:block; font-size:14px; color:#FFF; background: #0b85c6; /* Old browsers */ background: -moz-linear-gradient(top, #0b85c6 0%, #59b 100%); /* FF3.6+ */ background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#0b85c6), color-stop(100%,#59b)); /* Chrome,Safari4+ */ background: -webkit-linear-gradient(top, #0b85c6 0%,#59b 100%); /* Chrome10+,Safari5.1+ */ background: -o-linear-gradient(top, #0b85c6 0%,#59b 100%); /* Opera11.10+ */ background: -ms-linear-gradient(top, #0b85c6 0%,#59b 100%); /* IE10+ */ filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#0B85C6', endColorstr='#59B',GradientType=0 ); /* IE6-9 */ background: linear-gradient(top, #0b85c6 0%,#59b 100%); /* W3C */ font-family:"Lucida Sans Unicode", "Lucida Grande", sans-serif; height:26px; width:60px; margin:7px; text-align:center; padding-bottom:4px; padding-left:4px; padding-right:4px; float:left; margin-right:5px; } #bottombar { width:100%; height:50px; } {}

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  • Uses of Erlang in Telecom

    - by user94154
    I'm a web developer and a college student majoring in telecommunications. This means I'm decent at programming and I know a little about telecom networks (at a high, non-technical level). I keep reading that Erlang is used all over the telecom industry (supposedly for its performance). I'm wondering if there's anyway I can combine my programming skills with my telecommunications major with Erlang. Is most of the Erlang/telecom stuff closed source? Are there any open source telecom projects written Erlang? UPDATE: sipwiz's comment makes me think in terms of a question larger than "uses of Erlang". How can I leverage a high-level understanding of telecom networks and the telecom regulatory environment with programming. I hope this hasn't veered too off-topic for SO.

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  • HLSL tex2d sampler seemingly returning incorrect values; why?

    - by BlueNovember
    Hello all, I have code that needs to render regions of my object differently depending on their location. I am trying to use a colour map to define these regions, then get a value (0-14) representing this region by sampling the texture. The problem is when I sample from my colour map, I get collisions. Ie, two regions with different colours in the colourmap get the same value returned from the sampler. I've tried various formats of my colour map. I set the colours for each region to be "5" apart in each case; Indexed colour RGB, RGBA: region 1 will have RGB 5,5,5. region 2 will have RGB 10,10,10 and so on. HSV Greyscale: region 1 will have HSV 0,0,5. region 2 will have HSV 0,0,10 and so on. The tex2D sampler returns a value [0..1]. To get the "region number" I multiply this by 100 and divide by 5, expecting a number [0..20]. (But currently only using 0-14) I am using Shader Model 2 and FX Composer. //Colour map texture gColourmapTexture < string ResourceName = "Globe_Colourmap_Regions_Greyscale.png"; string ResourceType = "2D"; >; sampler2D gColourmapSampler : register(s1) = sampler_state { Texture = <gColourmapTexture>; #if DIRECT3D_VERSION >= 0xa00 Filter = MIN_MAG_MIP_LINEAR; #else /* DIRECT3D_VERSION < 0xa00 */ MinFilter = Linear; MipFilter = Linear; MagFilter = Linear; #endif /* DIRECT3D_VERSION */ AddressU = Clamp; AddressV = Clamp; }; ... //Then later, in a method float region = tex2D(gColourmapSampler,In.UV).x; //at this point I do not think it matters which of xyz components I pick; even in HSV they're all the same for my image. region *= 100; //Now in range [0..100] region /= 5; //Now in range [0..20] float3 levels[21]; //*Code populating "levels" array with what is essentially colour information * levels[1] = ... levels[2] = ... //Chose which level this region has, by looking up its region number float3 Level = levels[region];

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  • Neural Network problems

    - by Betamoo
    I am using an external library for Artificial Neural Networks in my project.. While testing the ANN, It gave me output of all NaN (not a number in C#) The ANN has 8 input , 5 hidden , 5 hidden , 2 output, and all activation layers are of Linear type , and it uses back-propagation, with learning rate 0.65 I used one testcase for training { -2.2, 1.3, 0.4, 0.5, 0.1, 5, 3, -5 } ,{ -0.3, 0.2 } for 1000 epoch And I tested it on { 0.2, -0.2, 5.3, 0.4, 0.5, 0, 35, 0.0 } which gave { NaN , NaN} Note: this is one example of many that produces same case... I am trying to discover whether it is a bug in the library, or an illogical configuration.. The reasons I could think of for illogical configuration: All layers should not be linear Can not have descending size layers, i.e 8-5-5-2 is bad.. Only one testcase ? Values must be in range [0,1] or [-1,1] Is any of the above reasons could be the cause of error, or there are some constraints/rules that I do not know in ANN designing..? Note: I am newbie in ANN

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