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  • Faye private pub web sockets Errno::ECONNREFUSED: Connection refused - connect(2)

    - by Rubytastic
    Faye private pub has issues connecting. It works from rails console and from inside application. It fails when called from background process like delayed_job or sidekiq. I have been unable to resolve this issue for some time now, does anyone know why this happens? Errno::ECONNREFUSED: Connection refused - connect(2) /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/resolv-replace.rb:23:in initialize' /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/resolv-replace.rb:23:in initialize' /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:878:in open' /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:878:in block in connect' /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/timeout.rb:52:in timeout' /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:877:in connect' /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:862:in do_start' /Users/jordan/.rvm/rubies/ruby-2.0.0-p247/lib/ruby/2.0.0/net/http.rb:851:in start' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/private_pub-1.0.3/lib/private_pub.rb:42:in publish_message' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/private_pub-1.0.3/lib/private_pub.rb:29:in publish_to' /srv/books/app/workers/session_reload.rb:16:in perform' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/processor.rb:48:in block (3 levels) in process' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:119:in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:119:inblock in invoke' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/newrelic_rpm-3.6.8.168/lib/new_relic/agent/instrumentation/sidekiq.rb:25:in block in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/newrelic_rpm-3.6.8.168/lib/new_relic/agent/instrumentation/controller_instrumentation.rb:324:in perform_action_with_newrelic_trace' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/newrelic_rpm-3.6.8.168/lib/new_relic/agent/instrumentation/sidekiq.rb:21:in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:121:inblock in invoke' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-failures-0.2.2/lib/sidekiq/failures/middleware.rb:10:in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:121:inblock in invoke' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/server/active_record.rb:6:in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:121:inblock in invoke' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/server/retry_jobs.rb:62:in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:121:inblock in invoke' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/server/logging.rb:11:in block in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/logging.rb:22:in with_context' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/server/logging.rb:7:in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:121:inblock in invoke' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:124:in call' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/middleware/chain.rb:124:ininvoke' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/processor.rb:47:in block (2 levels) in process' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/processor.rb:102:in stats' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/processor.rb:46:in block in process' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/processor.rb:83:in do_defer' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/sidekiq-2.16.0/lib/sidekiq/processor.rb:37:in process' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/celluloid-0.15.2/lib/celluloid/calls.rb:25:in public_send' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/celluloid-0.15.2/lib/celluloid/calls.rb:25:in dispatch' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/celluloid-0.15.2/lib/celluloid/calls.rb:122:in dispatch' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/celluloid-0.15.2/lib/celluloid/actor.rb:322:in block in handle_message' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/celluloid-0.15.2/lib/celluloid/actor.rb:416:in block in task' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/celluloid-0.15.2/lib/celluloid/tasks.rb:55:in block in initialize' /Users/jordan/.rvm/gems/ruby-2.0.0-p247@books/gems/celluloid-0.15.2/lib/celluloid/tasks/task_fiber.rb:13:in block in create' Processor: dev-air.local:db67c04914cdef80c501043115298f6d-70211452597260

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  • google book api

    - by ohana
    hi, i need to add google's book preview button in my web app. I tried Google Book Search APIs, and used their dynamic links, and added the following in my jquery code: var cburl = "http://books.google.com/books"; var api_url = cburl + "?jscmd=viewapi&bibkeys=" + "0321525566"; document.write(unescape("%3Cscript src=" + api_url + " type='text/javascript'%3E%3C/script%3E")); from firebug, i can see google responsed: var _GBSBookInfo = {"0321525566":{"bib_key":"0321525566","info_url":"http://books.google.com/books?id=VBRePgAACAAJ\u0026source=gbs_ViewAPI","preview_url":"http://books.google.com/books?id=VBRePgAACAAJ\u0026cd=1\u0026source=gbs_ViewAPI","thumbnail_url":"http://bks4.books.google.com/books?id=VBRePgAACAAJ\u0026printsec=frontcover\u0026img=1\u0026zoom=5\u0026sig=ACfU3U2i79GUit7BKFSvfvuZ1daX4EpZjg","preview":"noview","embeddable":false}}; however jquery complaint 'No _GBSBookInfo is defined'. then i tried jquery's ajax as blow instead of Document.write(): $.ajax({ url:api_url, success: function(_GBSBookInfo) { alert(_GBSBookInfo); alert('load was performed'); } }); still got the same complaint...anyone can help?

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  • Lock free multiple readers single writer

    - by dummzeuch
    I have got an in memory data structure that is read by multiple threads and written by only one thread. Currently I am using a critical section to make this access threadsafe. Unfortunately this has the effect of blocking readers even though only another reader is accessing it. There are two options to remedy this: use TMultiReadExclusiveWriteSynchronizer do away with any blocking by using a lock free approach For 2. I have got the following so far (any code that doesn't matter has been left out): type TDataManager = class private FAccessCount: integer; FData: TDataClass; public procedure Read(out _Some: integer; out _Data: double); procedure Write(_Some: integer; _Data: double); end; procedure TDataManager.Read(out _Some: integer; out _Data: double); var Data: TDAtaClass; begin InterlockedIncrement(FAccessCount); try // make sure we get both values from the same TDataClass instance Data := FData; // read the actual data _Some := Data.Some; _Data := Data.Data; finally InterlockedDecrement(FAccessCount); end; end; procedure TDataManager.Write(_Some: integer; _Data: double); var NewData: TDataClass; OldData: TDataClass; ReaderCount: integer; begin NewData := TDataClass.Create(_Some, _Data); InterlockedIncrement(FAccessCount); OldData := TDataClass(InterlockedExchange(integer(FData), integer(NewData)); // now FData points to the new instance but there might still be // readers that got the old one before we exchanged it. ReaderCount := InterlockedDecrement(FAccessCount); if ReaderCount = 0 then // no active readers, so we can safely free the old instance FreeAndNil(OldData) else begin /// here is the problem end; end; Unfortunately there is the small problem of getting rid of the OldData instance after it has been replaced. If no other thread is currently within the Read method (ReaderCount=0), it can safely be disposed and that's it. But what can I do if that's not the case? I could just store it until the next call and dispose it there, but Windows scheduling could in theory let a reader thread sleep while it is within the Read method and still has got a reference to OldData. If you see any other problem with the above code, please tell me about it. This is to be run on computers with multiple cores and the above methods are to be called very frequently. In case this matters: I am using Delphi 2007 with the builtin memory manager. I am aware that the memory manager probably enforces some lock anyway when creating a new class but I want to ignore that for the moment. Edit: It may not have been clear from the above: For the full lifetime of the TDataManager object there is only one thread that writes to the data, not several that might compete for write access. So this is a special case of MREW.

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  • Ruby on Rails free books

    - by Madhan ayyasamy
    The following links has ruby on rails tutorials, you can download directly from there website, its fully free of cost..:)Beginning Ruby: From Novice to Professional Building Dynamic Web 2.0 Websites with Ruby on RailsRuby on Rails For DummiesAgile Web Development with RailsThe Ruby Way: Solutions and Techniques in Ruby ProgrammingBeginning Ruby on RailsRails RecipesRails CookbookAjax on RailsThe Art of Rails Programmer to Programmer

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  • free() on stack memory

    - by vidicon
    I'm supporting some c code on Solaris, and I've seen something weird at least I think it is: char new_login[64]; ... strcpy(new_login, (char *)login); ... free(new_login); My understanding is that since the variable is a local array the memory comes from the stack and does not need to be freed, and moreover since no malloc/calloc/realloc was used the behaviour is undefined. This is a real-time system so I think it is a waste of cycles. Am I missing something obvious?

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  • free RSS feed caching

    - by cherouvim
    Hello I've got an application which serves an rss feed of headlines and I need to provide this rss feed to other consumers. I don't want to provide the rss directly from my server though, due to limited server resources, so I need to proxy (cache) it through some service which will handle the load. Assuming the rss feed URL of my application is http://example.com/rss I initially provided my consumers with the url http://ajax.googleapis.com/ajax/services/feed/load?v=1.0&q=http%3A%2F%2Fexample.com%2Frss which solved my server load problem but introduced a liveness problem. The headlines are minutes to hours late from the actual feed (haven't exactly measured how much late). I've also tried distributing through feedburner so the url became something like http://feeds.feedburner.com/example123?format=xml but the liveness problem still exists. Is there a public and free solution for this problem? Anything below 5 minutes of liveness delay would be totally acceptable. thanks

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  • Free US sales-tax lookup (per zip etc.)?

    - by Shimmy
    I am creating a pricing program. I need to calculate the amounts according to the current tax list in the US (in various places). I want to have a button 'Update taxes' in the administrative settings of the application, so when the user clicks it, it should download from somewhere the active tax amounts. So I actually want to have a function decimal GetTax(string zip). Does anyone knows about a free downloadable xml, or RSS accessible or even a website that I can crawle in and get this info from?

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  • In WPF: Children.Remove or Children.Clear doesn't free objects

    - by Bart Roozendaal
    I create some UIElements from code behind and was anticipating the garbage collection to clear up stuff. However, the objects are not free-ed at the time I expected it. I was expecting them to be freeed at RemoveAt(0), but they are only freed at the end of the program. How can I make the objects be freed when removed from the Children collection of the Canvas? <Window x:Class="WpfApplication1.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Window1" Height="300" Width="300" MouseDown="Window_MouseDown"> <Grid> <Canvas x:Name="main" /> </Grid> </Window> The code behind is: public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); } private void Window_MouseDown(object sender, MouseButtonEventArgs e) { if (main.Children.Count == 0) main.Children.Add(new MyControl() { Background = Brushes.Yellow, Width = 100, Height = 50 }); else main.Children.RemoveAt(0); } } public class MyControl : UserControl { ~MyControl() { Debug.WriteLine("Goodbye"); } }

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  • PHP - "Fat Free Framework" Find Methods and Showing Results in Template

    - by user1672808
    Just started trying the "Fat Free Framework" I'm building a site using a MySQL DB with 265 fields, and 5000+ rows in the DB; I can load() a specific record easily, no problems. When using find(), afind(), and even "select()", template will show blank lines or lines with "filler" text, with the correct number of rows for the query results, but no text/data from the DB itself; Same problem whether using objects or simply arrays from result (afind() and find()). I've copied/pasted the code verbatim from examples and from documentation, with only the DB specific items changed. Still, no luck. CODE IN PHP FILE (function from CLASS): static function home() { $featured=new Axon('boats'); $F3::set('boatlist',$featured->afind('D_CustomerID=173')); F3::set('content',TEMPLATE_DIR .'/home.html'); echo Template::serve(TEMPLATE_DIR .'/layout.html'); } TEMPLATE home.html: <div class="span8"> <h3> Featured Boats </h3> <F3:repeat group="{{@boatlist}}" value="{{@boat}}"> <div style="margin-left: 2em" class="thumbnails"> <p> <a href="boat/{{@boat['D_BoatNum']}}">{{trim(@boat['D_Description'])}}</a> by {{@boat['D_CustomerID']}} </p> <p> {{@boat['D_Price']}} </p> </div> </F3:repeat> </div> The number of rows this produces coincides with the correct number of rows in the DB. However, the actual data from each field does not show. Any ideas?

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  • Lock-Free Data Structures in C++ Compare and Swap Routine

    - by slf
    In this paper: Lock-Free Data Structures (pdf) the following "Compare and Swap" fundamental is shown: template <class T> bool CAS(T* addr, T exp, T val) { if (*addr == exp) { *addr = val; return true; } return false; } And then says The entire procedure is atomic But how is that so? Is it not possible that some other actor could change the value of addr between the if and the assignment? In which case, assuming all code is using this CAS fundamental, it would be found the next time something "expected" it to be a certain way, and it wasn't. However, that doesn't change the fact that it could happen, in which case, is it still atomic? What about the other actor returning true, even when it's changes were overwritten by this actor? If that can't possibly happen, then why? I want to believe the author, so what am I missing here? I am thinking it must be obvious. My apologies in advance if this seems trivial.

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  • Recommendations for a free GIS library supporting raster images

    - by gspr
    Hi. I'm quite new to the whole field of GIS, and I'm about to make a small program that essentially overlays GPS tracks on a map together with some other annotations. I primarily need to allow scanned (thus raster) maps (although it would be nice to support proper map formats and something like OpenStreetmap in the long run). My first exploratory program uses Qt's graphics view framework and overlays the GPS points by simply projecting them onto the tangent plane to the WGS84 ellipsoid at a calibration point. This gives half-decent accuracy, and actually looks good. But then I started wondering. To get the accuracy I need (i.e. remove the "half" in "half-decent"), I have to correct for the map projection. While the math is not a problem in itself, supporting many map projection feels like needless work. Even though a few projections would probably be enough, I started thinking about just using something like the PROJ.4 library to do my projections. But then, why not take it all the way? Perhaps I might aswell use a full-blown map library such as Mapnik (edit: Quantum GIS also looks very nice), which will probably pay off when I start to want even more fancy annotations or some other symptom of featuritis. So, finally, to the question: What would you do? Would you use a full-blown map library? If so, which one? Again, it's important that it supports using (and zooming in and out with) raster maps and has pretty overlay features. Or would you just keep it simple, and go with Qt's own graphics view framework together with something like PROJ.4 to handle the map projections? I appreciate any feedback! Some technicalities: I'm writing in C++ with a Qt-based GUI, so I'd prefer something that plays relatively nicely with those. Also, the library must be free software (as in FOSS), and at least decently cross-platform (GNU/Linux, Windows and Mac, at least). Edit: OK, it seems I didn't do quite enough research before asking this question. Both Quantum GIS and Mapnik seem very well suited for my purpose. The former especially so since it's based on Qt.

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  • SQLAuthority News – Updates on Contests, Books and SQL Server

    - by pinaldave
    There are lots of things happening on this blog and I feel sometime it is difficult to keep up. One of the suggestion I keep on receiving if there is a single page where one can visit and know the updates. I did consider of the same at some point but in era of RSS Feed it is difficult to have proper audience to that page. Here are few updates on various contest and books give away in recent time. Combo set of 5 Joes 2 Pros Book – 1 for YOU and 1 for Friend – I have received so many entries for this contest. Many have sent me email asking if this contest can be extended by couple of days. For the same the deadline for this contest is now Nov 10th 7 AM. You can send your entries by that time. The prize is 2 combo set of Joes 2 Pros is of USD 444. If you have not take part in the contest please take part now. Guess What is in the box? – There were many entry for this contest. We played this contest on blog as well, facebook. The answer of this contest was announced in 2 days in blog post announcing my new book. The winner was Manas Dash from Bangalore. He answered “The box will contain SQL book authored by Vinod and Pinal”. This was the closest answer we received. Win 5 SQL Programming Book Contest will have winner announced by Nov 15th and winners will be sent email. Win 5 SQL Wait Stats Book Contest is closed and winners have been sent their award. My third book SQL Server Interview Questions and Answers have run out of stock in India in 36 hours of its launch. We are working very hard to make it available again. Thank you again for excellent support! Without your participation all the give away have no significance. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: About Me, Pinal Dave, PostADay, Readers Contribution, Readers Question, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Managing a Web Portal

    - by A competent translator
    After skimming almost all questions tagged "books" here at Pro Webmasters to find a book on managing web portals I found references to general web mastering. Are there books on managing and curating content of public web portals , i.e. a governmental portal for a given department or agency ? I need a reference on the day-to-day management and best practices of a portal and its content. Also welcomed are references on managing multilingual portals.

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  • What books help one to learn to read code?

    - by Daniel
    Lion's Commentary on Unix Sixth Edition with Source Code is a wonderful book to learn how to read code. Reading code is important -- how does one learn how to write excellent code without having read excellent code? But, sadly, while great writers, of fiction and non-fiction, all spend a great deal of time reading stuff, we, programmers, seem to avoid it like the plague. Worse still, programming books usually go the same way. They might show a pattern or a style, but they often avoid showing good, complex code, and helping one go through it. There are exceptions, of course. I hope. So, with that in mind, what books are to be found which help one learn how to read code?

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  • Why’s (Poignant) Guide to Ruby

    - by Ben Griswold
    You’re familiar with O’Reilly’s brilliant Head First Series, right?  Great.  Then you know how every book begins with an explanation of the Head First teaching style and you know the teaching format which Kathy Sierra and Bert Bates developed is based on research in cognitive science, neurobiology and educational psychology and it’s all about making learning visual and conversational and attractive and emotional and it’s highly effective.  Anyway, it’s a great series and you should read every last one of the books. Moving on… I’ve been wanting to learn more about Ruby and Why’s (Poignant) Guide to Ruby has been on my reading list for a while and there was talk about cartoon foxes and other silliness and I figured Why’s (Poignant) Guide to Ruby probably takes the same unorthodox teaching style as the Head First books – and that’s great – so I read the book, in piecemeal, over the last couple of weeks and, well, I figured wrong. Now having read the book, here’s my take on Why’s (Poignant) Guide – it’s very creative and clever and it does a darn good job of introducing one to Ruby.  If you’re interested in Ruby or simply interested, the online book is worth your time.  If you’re thinking (like me) that cartoon foxes will be doing the teaching, that’s simple not the case.  However, the cartoons and the random stories in the sidebar may serve a purpose. Unlike the Head First books where images and captions are used to further explain the teachings, the cartoons and stories in Why’s Guide serve as intermission and offer your brain a brief moment of rest before the next Ruby concept is explained.  It’s not a bad strategy, but definitely not as effective as the Head First techniques.  

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  • Where can I find free and open data?

    - by kitsune
    Sooner or later, coders will feel the need to have access to "open data" in one of their projects, from knowing a city's zip to a more obscure information such as the axial tilt of Pluto. I know data.un.org which offers access to the UN's extensive array of databases that deal with human development and other socio-economic issues. The other usual suspects are NASA and the USGS for planetary data. There's an article at readwriteweb with more links. infochimps.org seems to stand out. Personally, I need to find historic commodity prices, stock values and other financial data. All these data sets seem to cost money however. Clarification To clarify, I'm interested in all kinds of open data, because sooner or later, I know I will be in a situation where I could need it. I will try to edit this answer and include the suggestions in a structured manners. A link for financial data was hidden in that readwriteweb article, doh! It's called opentick.com. Looks good so far! Update I stumbled over semantic data in another question of mine on here. There is opencyc ('the world's largest and most complete general knowledge base and commonsense reasoning engine'). A project called UMBEL provides a light-weight, distilled version of opencyc. Umbel has semantic data in rdf/owl/skos n3 syntax. The Worldbank also released a very nice API. It offers data from the last 50 years for about 200 countries

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  • Good ruby book with exercises? [closed]

    - by watabou
    I find that I learn the best with a book that has a number of exercises at the end of each chapters. A great example of this is C++ Primer Plus by Stephen Prata or Scientific Programming with Python or the Horstmann Java books. All of those books have a number of programming exercises at the end tailored to that specific chapter. I love the styles of those book and was wondering if there is anything similar for Ruby. I've extensively searched google for this and people have been suggesting different stuff like different websites like Ruby Koans and LRTHW but honestly, I've tried those and they aren't for me. I taught myself Python with the the Hard Way book and to be honest, it's not for me. Now, forgive me if I'm blunt but does anyone have a Ruby programming BOOK (i.e. not a website), that has EXERCISES in it? I do NOT want a website, unless the book is only or is freely available online by the author, similar to the Hard Way books. I would say that I'm a intermediate level programmer with only some Ruby experience but if you know of a beginner book on Ruby, that is fine too. Thanks in advance, I would really really appreciate the help.

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  • Theory of computation - Using the pumping lemma for context free languages

    - by Tony
    I'm reviewing my notes for my course on theory of computation and I'm having trouble understanding how to complete a certain proof. Here is the question: A = {0^n 1^m 0^n | n>=1, m>=1} Prove that A is not regular. It's pretty obvious that the pumping lemma has to be used for this. So, we have |vy| = 1 |vxy| <= p (p being the pumping length, = 1) uv^ixy^iz exists in A for all i = 0 Trying to think of the correct string to choose seems a bit iffy for this. I was thinking 0^p 1^q 0^p, but I don't know if I can obscurely make a q, and since there is no bound on u, this could make things unruly.. So, how would one go about this?

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  • Where can one find free software icons / images?

    - by mmattax
    This may not be directly related to programming, but I always find it hard to get quality icons that can be used for software. I currently have the need for some type of "green checkmark image", and I always seem to be looking for print, save, delete types of icons... Anybody have good resources? Note: I rather not be stealing someone's intellectual property.

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  • Fiction that includes BASIC programs [closed]

    - by Clinton Blackmore
    Back in what must've been the mid-80s, when every microcomputer included BASIC and Choose Your Own Adventure Books were really popular, there were some novels that had BASIC programs listed in the text, for you to type in and further enjoy. For example, as I recall, in one of these books, the adventurers were infiltrating an undersea base (and eventually wiped the bad guy's data storage [I do believe it was a hard drive, even though they were uncommon then]). One of the programs involved a game were you piloted a submarine and had to avoid or shoot sharks. The code was in BASIC; minor changes (such as 'CLS' - 'HOME') had to be made for your specific computer, and it used good old 40-column text-mode to display the action. IIRC, the plot never depended upon the programs. My question is, does anyone else recall these sorts of books? Do you know any titles that I could look for, or of any online? I am toying with the idea of writing a story like this (no, not in BASIC!), and would really like to see how it was done, back in the day.

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  • Advice on choosing a book to read

    - by Kioshiki
    I would like to ask for some recommendations on useful books to read. Initially I had intended on posting quite a long description of my current issue and asking for advice. But I realised that I didn’t have a clear idea of what I wanted to ask. One thing that is clear to me is that my knowledge in various areas needs improving and reading is one method of doing that. Though choosing the right book to read seems like a task in itself when there are so many books out there. I am a programmer but I also deal with analysis, design & testing. So I am not sure what type of book to read. One option might be to work through two books at the same time. I had thought maybe one about design or practices and another of a more technical focus. Recently I came across one book that I thought might be useful to read: http://xunitpatterns.com/index.html It seems like an interesting book, but the comments I read on amazon.co.uk show that the book is probably longer than it needs to be. Has anyone read it and can comment on this? Another book that I already own and would probably be a good one to finish reading is this: http://www.amazon.co.uk/Code-Complete-Practical-Handbook-Construction/dp/0735619670/ref=sr_1_1?ie=UTF8&qid=1309438553&sr=8-1 Has anyone else read this who can comment on its usefulness? Beyond these two I currently have no clear idea of what to read. I have thought about reading a book related to OO design or the GOF design patterns. But I wonder if I am worrying too much about the process and practices and not focusing on the actual work. I would be very grateful for any suggestions or comments. Many Thanks, Kioshiki

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