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• How do I create a Magento module or widget that will appear on the shopping cart page?

  - by user303449

  I’m having a lot of trouble understanding how to create a module that will add an extra button to the shopping cart page. I found lots of info on payment modules and stand-a-lone page modules, but nothing for this. I simply need to add a button underneath the regular “Checkout” button that can post item data to another website. I’ve created a module but can’t get Magento to recognize it and display the button on that spot. Any help would be greatly appreciated, even just sending me to an existing tutorial that I haven’t been able to find. Thanks.

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• Display values and how many times they occured using a Dictionary

  - by user1730056

  I've been told to By using a dictionary (or your solution to Part 4), write a method at_least(a, n) that takes a list, a, and an integer, n, as arguments and returns a list containing only the elements of a that occur at least n times. For complete marks, the list should contain the elements in order of their first occurrence in a. I was able to figure this without using a dictionary, with def at_least2(a, n): return [x for x in a if a.count(x) is n] I was wondering how I can write this using a dictionary? The input is: a = [-6, 8, 7, 3, 2, -9, 1, -3, 2, -4, 4, -8, 7, 8, 2, -2, -7, 0, 1, -9, -3, -7, -3, -5, 6, -3, 6, -3, -10, -8] def at_least(a, 2): and the output: [8, 7, 2, -9, 1, -3, 2, -8, 7, 8, 2, -7, 1, -9, -3, -7, -3, 6, -3, 6, -3, -8] Edit: I don't understand how a dictionary is being used, yet the output isn't in dictionary form? My understanding is that dictionaries have values for each object. I'm not sure if I'm using the right terms.

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• Why should "miter" joints be slower than others?

  - by Hanno Fietz

  I'm having a graphics problem on drawing lines in Flash Player, where two lines drawn on top of each other with different thickness don't align properly if I use any other JointStyle than MITER. For pictures of the effect, and for the graphics oriented part of the question, see my post over on doctype. However, there's also a second angle on this problem, which is: why should drawing the "mitered" joints be so much slower than others? This seems to be a problem since at least FP 8, but I couldn't find any detailed info on what the problem might be. Is this just an ordinary bug that didn't get fixed yet, or is there something inherently slower about drawing these joints? For example, they seem to have something to do with square roots, but I seriously lack understanding of what this joint style thing is all about, technically. It just looks like some minor detail a graphic designer might worry about. I'm asking because I'm wondering if I can do something to mitergate, er, mitigate, the problem.

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• Learning C++ from AS3

  - by grey

  I'm a decent AS3 programmer. I work in games, and that is my reason for programming. While there is much I can accomplish with Adobe AIR, my understanding at this point is that learning C++ is probably a good direction to take. I would learn a lot of valuable lower level programming if I needed it down the road, and I would have an easier time learning other C oriented languages. I see a lot of information for people looking to learn AS3 who know C++, but not the other way around. Why C++? Cross platform compatibility is important to me, so I'm not particularly interested in C# or Objective-C at this junction. I'm also aware of HaXe, and while I love the concept, after doing some research I'm worried about investing a lot of time into something so recent with limited learning resources and documentation. I'm looking for advice and resources (books, articles) related to this topic. Thanks in advance!

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• problems with Haskell's Number Types

  - by mindeavor.

  I have the following haskell code: fac n = product [1..n] taylor3s w0 f f' f'' t h = w1 : taylor3s w1 f f' f'' (t+h) h where hp i = h^i / fac i w1 = w0 + (hp 1) * f t w0 + (hp 2) * f' t w0 + (hp 3) * f'' t w0 taylor_results = take 4 $ taylor3s 1 f f' f'' 1 0.25 where f t x = t^4 - 4*x/t f' t x = 4*t^3 - 4*(f t x)/t + 4*x/t^2 f'' t x = 12*t^2 - 4*(f' t x)/t + 8*(f t x)/t^2 - 8*x/t^3 taylor_results is supposed to be a use case of taylor3s. However, there is something wrong with the number type inferencing. When I try to compile, this is the error I get: practice.hs:93:26: Ambiguous type variable `a' in the constraints: `Integral a' arising from a use of `taylor3s' at practice.hs:93:26-51 `Fractional a' arising from a use of `f' at practice.hs:93:37 Possible cause: the monomorphism restriction applied to the following: taylor_results :: [a] (bound at practice.hs:93:0) Probable fix: give these definition(s) an explicit type signature or use -XNoMonomorphismRestriction Can someone help me with understanding what the problem is?

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• PHP no wait sem_acquire?

  - by SerEnder

  Not a specific code question, but more of a general coding question. I'm trying to use a semaphore in a work project to limit the number of users that can access certain processes at a concurrent time. From my understanding the following: $iKey = ftock($sSomeFileLocation,'sOneCharacterString'); //Generate the key if($sem_id = sem_get($iKey){ //1 user allowed if(sem_acquire($sem_id)){ //Do the limited process here sem_release($sem_id); } } The problem that I see here is that if there is already one user who has the semaphore key, then the next user just waits until the first user is done rather than just faulting out. Anyone know of a way that if the max_acquire number has been reached, sem_acquire (or similar) will just return false? Thanks

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• How do I prevent a pair of XMLEvent[Reader|Writer] from splitting empty tags into start+end tags?

  - by java.is.for.desktop

  Hello, everyone! I have an understanding problem of how the following code works: XMLInputFactory xif = XMLInputFactory.newFactory(); XMLOutputFactory xof = XMLOutputFactory.newFactory(); XMLEventReader reader = xif.createXMLEventReader(/* ... */); XMLEventWriter writer = xof.createXMLEventWriter(/* ... */); writer.add(reader); The method writer.add([some reader]) reads all events from reader and writes them consequently. Sadly, following happens: The input <root><c/></root> gets transformed to <root><c><c/></root> I know, from XML point of view, these are equal trees, but not for a human ;) What can I do to get the same output? FYI: I need a XMLEvent[Reader|Writer] pair later to filter "XML events".

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• Is the offical Sun Java EE tutorial the best way to learn how to make Java web apps?

  - by Nick

  I've been a web developer for almost a decade. I've mostly used classic ASP/JavaScript and I'd like to move into Java based apps. I have a decent understanding of Java itself (enough to know how to lookup what I don't know) and I spent some time doing minor work on a JSF/Spring/Hibernate app, but from what a trusted coworker told me, this application is the example of what not to do. I want to learn the really hardcore stuff (EJBs, HA Clustering, etc), but I know I have to walk before I can run. Is the Sun Tutorial the best place to start? Or is there an definitive book (like K&R for C or Gang of Four for design patterns) that I should buy?

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• Given a document select a relevant snippet.

  - by BCS

  When I ask a question here, the tool tips for the question returned by the auto search given the first little bit of the question, but a decent percentage of them don't give any text that is any more useful for understanding the question than the title. Does anyone have an idea about how to make a filter to trim out useless bits of a question? My first idea is to trim any leading sentences that contain only words in some list (for instance, stop words, plus words from the title, plus words from the SO corpus that have very weak correlation with tags, that is that are equally likely to occur in any question regardless of it's tags)

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• Pseudorandom Number Generation with Specific Non-Uniform Distributions

  - by carnun

  Hello all, I'm writing a program that simulates various random walks (with differing distributions). At each timestep, I need randomly generated, two dimensional step distances and angles from the distribution of the random walk. I'm hoping someone can check my understanding of how to generate these random numbers. As I understand it I can use Inverse Transform Sampling as follows: If f(x) is the pdf of our random walk that has a non-uniform distribution, and y is a random number from a uniform distribution. Then if we let f(x) = y and solve to find x then we have a random number from the non-uniform distribution. Is this a feasible solution?

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• Hibernate entities stored as HttpSession attribute values

  - by njudge

  I'm dealing with a legacy Java application with a large, fairly messy codebase. There's a fairly standard 'User' object that gets stored in the HttpSession between requests, so the servlets do stuff like this at the top: HttpSession session = request.getSession(true); User user = (User)session.getAttribute("User"); The old user authentication layer (which I won't describe; suffice to say, it did not use a database) is being replaced with code mapped to the DB with Hibernate. So 'User' is now a Hibernate entity. My understanding of Hibernate object life cycles is a little fuzzy, but it seems like storing 'User' in the HttpSession now becomes a problem, because it will be retrieved in a different transaction during the next request. What is the right thing to be doing here? Can I just use the Hibernate Session object's update() method to reattach the User instance the next time around? Do I need to?

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• Objective C instance variables - Newbie

  - by Dwayne King

  OK - so I'm sure my confusion here is just a result of being stuck in a "Java mindset" and not understanding how Obj C differs in this case. In Java, I can declare a variable in a class, like this, and each instance of that class will have it's own: MyClass { String myVar; MyClass() { // constructor } } In Obj C I tried to do the same thing by declaring a variable only in the .m file like this: #import "MyClass.h" @implementation MyClass NSString *testVar; @end My expectation here was that this variable has a scope limited to this class. So I created a second class (identical): #import "MySecondClass.h" @implementation MySecondClass NSString *testVar; @end What I'm seeing (and has me baffled) is that changing the variable in one class, affects the value seen in the other class. In fact, if I set a breakpoint, and then "Jump to Definition" of the variable, it takes me to th I've created an extremely small XCode project that demonstrates the problem here Nothing more humbling than moving to a new language :) Thanks in advance.

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• Getting the hang of CodeIgniter - Templating / loading views

  - by kilrizzy

  Attempting to learn CI and going through the docs to get a better understanding. Without getting a separate library, I could make a template by including a list of views like so: $this->load->view('header'); $this->load->view('navigation'); $this->load->view('sidenav_open'); $this->load->view('blocks/userinfo'); $this->load->view('blocks/stats'); $this->load->view('sidenav_close'); $this->load->view('content',$data); $this->load->view('footer'); This makes sense but would I actually have that on each of my controllers (pages)? Not sure if there is a way to include this in the initial controller (welcome) and then in the others somehow reference it? Or perhaps there is something I am missing completely

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• How to Vertically Center Images on a Line?

  - by jeremy

  What's the best way to center icons on a line when the images are smaller than the line height? For example (styles inline for easier reading): <div style="line-height: 20px"> <img style="width: 12px; height: 12px;"/> Blah blah blah </div> Here's a jsFiddle example. This example also shows why vertical-align: middle does not work. I want the img to be centered against the text of the div. That is, even if the text wrapped to multiple lines, the image would be centered against a single line. Ideally, the solution would not involve setting margings/paddings on the image and would work even if I didn't know the line-height. Things I've read: How do I vertically align text next to an image with CSS? (deals with case where image is larger, doesn't seem to apply here) Understanding vertical-align

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• memset on array of structures in C++

  - by garry

  I have another memset question. It appears as if the code I am editing may have some issues (or it's not done the same way in different files) A::LRM las[9]; //A and LRM are both structures with BOOLS and INTS memset(&las, 0, sizeof(las)); typedef Sec SecArray[16]; SecArray rad_array; memset(rad_array, 0, sizeof(SecArray)); The second example appears to be correct because rad_array is the same as the first position in the array. Then the sizeof(SecArray)) would make sense. The first one doesn't seem correct to me. All structs are just BOOLs and INTS nothing dynamic in them. My understanding from my other post about memset was that it followed this format. memset("pointer to object", "what to set it to", "size of object") Can anyone tell me what exactly is going on here if I am incorrect with my theory.

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• WPF UserControl event called only once?

  - by 742

  Hi Everyone, I need to bind two-way a property of a user control to a property of a containing user control. I also need to set a default value to the property from code in the child (cannot be done easily from XAML tags). If I call my code from the child constructor, the value is set in the parent but the change callback routine is not triggered (my understanding is that the parent doesn't yet exist at the time the child is created). My current workaround is to catch the Loaded event of the child and to call the code from the handler. Howver as Loaded is called more than once, I need to set a flag to set the property only the first time. I don't like this way, but I don't know if there is a single shot event that could be used, or if this can be done otherwise. Any feedback based on your experience?

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• Casting to specific asp.net page type

  - by DEH

  I have an asp.net page with a code-behind class definition as follows: public partial class examplepage : System.Web.UI.Page I'd like to set a public property within the page that I can reference from other classes. My understanding is that if I cast to examplepage then I should be able to get at the public property that is specific to example page, as in: string test=((examplepage)HttpContext.Current.Handler).propertyX; However, when I try casting as above the compiler does not recognise examplepage. Can anyone tell me how I can cast? I have no specific namespaces defined. Thanks

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• How to work around a site forbidding me to scrape their images with PHP

  - by Petruza

  I'm scraping a site, searching for JPGs to download. Scraping the site's HTML pages works fine. But when I try getting the JPGs with CURL, copy(), fopen(), etc., I get a 403 forbiden status. I know that's because the site owners don't want their images scraped, so I understand a good answer would be just don't do it, because they don't want you to. Ok, but let's say it's ok and I try to work around this, how could this be achieved? If I get the same URL with a browser, I can open the image perfectly, it's not that my IP is banned or anything, and I'm testing the scraper one file at a time, so it's not blocking me because I make too many requests too often. From my understanding, it could be that either the site is checking for some cookies that confirm that I'm using a browser and browsing their site before I download a JPG. Or that maybe PHP is using some user agent for the requests that the server can detect and filter out. Anyway, have any idea?

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• How to start coding the "Dining Philosophers" simulation?

  - by GrizzlyGuru

  I'm not a beginner at C# but I really need to increase my understanding, so I've picked a classic deadlock problem to code to help teach myself some of the more advanced concepts of C#. The Dining Philosophers Problem seems like a good one, but I need a little help to get started. I know I need to approach the "diners" as objects, but to simulate the random delays between eating, should I look to threading with each diner in a separate thread? Do I need some kind of "master" to monitor all the actions? Any general design concept advice is welcome, but I'd like to do the grunt programming as an exercise. Thanks!

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• PHP CURL works fine from localhost not from server

  - by Joby Joseph

  I have 2 servers, srv1 and srv2. All client sites are stored in srv2 and all authentication details are stored in srv1. Each time a client site is loaded, the site in srv2 sends a curl request to srv1 to validate. I am always getting bool(false) when I print the curl response using var_dump. But if I am requesting for validation from my local wamp installation(localhost) it is perfectly returning the response. According to my understanding srv2 is blocking srv1 ip or something like that. Any help or suggestions will be greatly appreciated. The solution is really urgent as all my clients are stuck with invalid authorization message. Edit: Now when i tested curl in srv2 is working fine i think. Because I am able to fetch other websites without any trouble. But I am not able to fetch data from srv1. I can view a page from srv1 through browser url but not through curl.

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• Removing the last character of a string IF it is $variable

  - by KeenLearner

  Hi there, I've made a little script to convert titles into url friendly things. ie: 'I am a title' becomes 'I_am_a_title' My script basically goes through and turns spaces, apostrophes, commas etc etc into an underscore. The problem is, sometimes my url's end up like this: 'i_am_a_title_' with a trailing underscore... So i figure, add a little bit to go through and search to see if the last character is an underscore on the final result, and if it is, then swap it. I looked into the strrchr() function but I seem to be hitting a wall of my own understanding. How is this sort of thing accomplished?

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• How To: Call a web service from ajax

  - by Kolten

  I have a simple Web Service that send email and is called via: public bool SendMail(string format, string from, string to, string cc, string bcc, string subject, string body, string replyTo) I have never used ajax before, and find I need to call this service and pass form contents to it from a simple html page (I cannot use asp or asp.net unfortunately). Can I get a quick rundown of what is required? I have searched for simple examples, but find I am having difficulty understanding how to call it and pass the parameters required of the Web Service. Thanks all!

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• Unsafe, super-fast cross-process memory buffer?

  - by John

  Cross-process memory buffers always have some overhead, and my understanding is this is quite high. But what if you're implementing a cross-process render-buffer, this isn't critically important in the same way as other data so are there techniques we can use to get 'raw' access to a chunk of memory from multiple processes, with no safety nets apart from it not crashing? Or do modern operating systems simply not work with unabstracted memory in a way to make this possible? I'm working in C++ but the question applies to Win XP/Vista/7, MacOSX 10.5+ (& Linux less importantly).

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• Rails routes looking for show action

  - by user1334345

  I am pretty new to rails and basically I want to make a user registration form. I am currently using rails 3.2.3 Basically I want to make basic routes like user/register on top of basic REST route for user. Here are my routes.rb resources :user do collection do get 'register' end end And here are my rake routes: register_user_index GET /user/register(.:format) user#register user_index GET /user(.:format) user#index POST /user(.:format) user#create new_user GET /user/new(.:format) user#new edit_user GET /user/:id/edit(.:format) user#edit user GET /user/:id(.:format) user#show PUT /user/:id(.:format) user#update DELETE /user/:id(.:format) user#destroy From my understanding, since register user is on top of show, it should match with register first before going to show. However, when I try to do localhost:3000/user/register, it gives me this error: No route matches {:action="show", :controller="user"} Can somebody help me with this? Thanks!!

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• Which is the future of web development: HTML5 or Silverlight(or other RIA framework)?

  - by Morgan Cheng

  My colleagues have a heated debate on what is the future of web development. One side is supporting HTML5 and the other is supporting Silverlight. There is no conclusion of the debate yet. In my humble opinion as a programmer, HTML5 will not improve programming productivity, while Silverlight will. In my understanding, programmers still need to program in JavaScript to take advantage of HTML5. For Silverlight, we can use C# which is static-type language. A lot of coding defects can be found in compilation time. For HTML5, different browsers might still have different behavior even though there is spec. For Silverlight, generally what works in IE will work the same way in other browsers. Just my thoughts. Any idea on how to choose future direction of web development?

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