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  • PHP Localization Best Practices? gettext?

    - by nute
    We are in the process of making our website international, allowing multiple languages. I've looked into php's "gettext" however, if I understand it right, I see a big flaw: If my webpage has let's say "Hello World" as a static text. I can put the string as <?php echo gettext("Hello World"); ?>, generate the po/mo files using a tool. Then I would give the file to a translator to work on. A few days later we want to change the text in English to say "Hello Small World"? Do I change the value in gettext? Do I create an english PO file and change it there? If you change the gettext it will consider it as a new string and you'll instantly loose the current translation ... It seems to me that gradually, the content of the php file will have old text everywhere. Or people translating might have to be told "when you see Hello World, instead, translate Hello Small World". I don't know I'm getting confused. In other programming languages, I've seen that they use keywords such as web.home.featured.HelloWorld. What is the best way to handle translations in PHP? Thanks

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  • Why doesn't every class in the .Net framework have a corresponding interface?

    - by Thorsten Lorenz
    Since I started to develop in a test/behavior driven style, I appreciated the ability to mock out every dependency. Since mocking frameworks like Moq work best when told to mock an interface, I now implement an interface for almost every class I create b/c most likely I will have to mock it out in a test eventually. Well, and programming to an interface is good practice, anyways. At times, my classes take dependencies on .Net classes (e.g. FileSystemWatcher, DispatcherTimer). It would be great in that case to have an interface, so I could depend on an IDispatcherTimer instead, to be able to pass it a mock and simulate its behavior to see if my system under test reacts correctly. Unfortunately both of above mentioned classes do not implement such interfaces, so I have to resort to creating adapters, that do nothing else but inherit from the original class and conform to an interface, that I then can use. Here is such an adapter for the DispatcherTimer and the corresponding interface: using System; using System.Windows.Threading; public interface IDispatcherTimer { #region Events event EventHandler Tick; #endregion #region Properties Dispatcher Dispatcher { get; } TimeSpan Interval { get; set; } bool IsEnabled { get; set; } object Tag { get; set; } #endregion #region Public Methods void Start(); void Stop(); #endregion } /// <summary> /// Adapts the DispatcherTimer class to implement the <see cref="IDispatcherTimer"/> interface. /// </summary> public class DispatcherTimerAdapter : DispatcherTimer, IDispatcherTimer { } Although this is not the end of the world, I wonder, why the .Net developers didn't take the minute to make their classes implement these interfaces from the get go. It puzzles me especially since now there is a big push for good practices from inside Microsoft. Does anyone have any (maybe inside) information why this contradiction exists?

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  • C# Regex - Replace multiple characters at once without overwriting?

    - by Everaldo Aguiar
    Hello guys, I'm implementing a c# program that should automatize a Mono-alphabetic substitution cipher. The functionality i'm working on at the moment is the simplest one: The user will provide a plain text and a cipher alphabet, for example: Plain text(input): THIS IS A TEST Cipher alphabet: A - Y, H - Z, I - K, S - L, E - J, T - Q Cipher Text(output): QZKL KL QJLQ I thought of using regular expressions since I've been programming in perl for a while, but I'm encountering some problems on c#. First I would like to know if someone would have a suggestion for a regular expression that would replace all occurrence of each letter by its corresponding cipher letter (provided by user) at once and without overwriting anything. Example: In this case, user provides plaintext "TEST", and on his cipher alphabet, he wishes to have all his T's replaced with E's, E's replaced with Y and S replaced with J. My first thought was to substitute each occurrence of a letter with an individual character and then replace that character by the cipherletter corresponding to the plaintext letter provided. Using the same example word "TEST", the steps taken by the program to provide an answer would be: 1 - replace T's with (lets say) @ 2 - replace E's with # 3 - replace S's with & 4 - Replace @ with E, # with Y, & with j 5 - Output = EYJE This solution doesn't seem to work for large texts. I would like to know if anyone can think of a single regular expression that would allow me to replace each letter in a given text by its corresponding letter in a 26-letter cipher alphabet without the need of splitting the task in an intermediate step as I mentioned. If it helps visualize the process, this is a print screen of my GUI for the program: http://img43.imageshack.us/img43/2118/11618743.jpg

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  • Is there any special tool for interactive GUI development

    - by niko
    Hi, Currently I am preparing exercises about networks and mobile communications for students. I was thinking about creating an interactive user-interface which enables the user to drag&drop predefined elements and then implement a logic based upon element distances etc. An example would be to place two base stations (a predefined element with several properties), set the scale in the interface and then check the signal interferrence in the environment (user-interface). The first part might be too abstract whereas the example might be too specific, but I was wondering whether there already exists any friendly framework or language which enables developers to create interactive interfaces (for teaching/learning purpouses) in short ammount of time. Usually I write applications for PC environment in .NET but in this case it would take too much time to create a specific interface for every exercise. I would appreciate if anyone could suggest any way to create interactive user-interface in short ammount of time. Are there any special programming languages or development tools for this kind of applications or are there any useful frameworks for .NET, Java or any other language to speed up the development of user-interfaces? Thank you!

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  • Is any solution the correct solution?

    - by Eli
    I always think to myself after solving a programming challenge that I have been tied up with for some time, "It works, thats good enough". I don't think this is really the correct mindset, in my opinion and I think I should always be trying to code with the greatest performance. Anyway, with this said, I just tried a ProjectEuler question. Specifically question #2. How could I have improved this solution. I feel like its really verbose. Like I'm passing the previous number in recursion. <?php /* Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be: 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... Find the sum of all the even-valued terms in the sequence which do not exceed four million. */ function fibonacci ( $number, $previous = 1 ) { global $answer; $fibonacci = $number + $previous; if($fibonacci > 4000000) return; if($fibonacci % 2 == 0) { $answer = is_numeric($answer) ? $answer + $fibonacci : $fibonacci; } return fibonacci($fibonacci, $number); } fibonacci(1); echo $answer; ?> Note this isn't homework. I left school hundreds of years ago. I am just feeling bored and going through the Project Euler questions

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  • Launching a modal UINavigationController

    - by Alexi Groove
    I'd like to launch a modal view controller the way one does with 'ABPeoplePickerNavigationController' and that is without having to creating a navigation controller containing the view controller. Doing something similar yields a blank screen with no title for the navigation bar and there's no associated nib file loaded for the view even though I am invoking the initWithNibName when the 'init' is called. My controller looks like: @interface MyViewController : UINavigationController @implementation MyViewController - (id)init { NSLog(@"MyViewController init invoked"); if (self = [super initWithNibName:@"DetailView" bundle:nil]) { self.title = @"All Things"; } return self; } - (void)viewDidLoad { [super viewDidLoad]; self.title = @"All Things - 2"; } @end When using the AB controller, all you do is: ABPeoplePickerNavigationController *picker = [[ABPeoplePickerNavigationController alloc] init]; picker.peoplePickerDelegate = self; [self presentModalViewController:picker animated:YES]; [picker release]; ABPeoplePickerNavigationController is declared as: @interface ABPeoplePickerNavigationController : UINavigationController The other way to create a modal view as suggested in Apple's 'View Controller Programming Guide for iPhone OS': // Create a regular view controller. MyViewController *modalViewController = [[[MyViewController alloc] initWithNibName:nil bundle:nil] autorelease]; // Create a navigation controller containing the view controller. UINavigationController *secondNavigationController = [[UINavigationController alloc] initWithRootViewController:modalViewController]; // Present the navigation controller as a modal view controller on top of an existing navigation controller [self presentModalViewController:secondNavigationController animated:YES]; I can create it this way fine (as long as I change the MyViewController to inherit from UIViewController instead of UINavigationController). What else should I be doing to MyViewController to launch the same way as ABPeoplePickerNavigationController?

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  • program "is not up to date" execution error in wedit lcc-win32

    - by Rowhawn
    I'm attempting to compile a simple hello world program in c with lcc-win32/wedit, and i'm a little unfamiliar with windows c programming. #include int main(void){ printf("hellow\n"); return 0; } When I compile the program the console output is Wedit output window build: Tue Jun 15 09:13:17 2010 c:\lcc\lib\lcccrt0.obj .text: undefined reference to '_RtlUnwind@16' c:\lcc\lib\lcccrt0.obj .text: undefined reference to '_signal' c:\lcc\lib\lcccrt0.obj .text: undefined reference to '_raise' c:\lcc\lib\lcccrt0.obj .text: undefined reference to '_exit' asctoq.obj .text: undefined reference to '_strnicmp' defaulttrap.obj .text: undefined reference to 'imp_iob' defaulttrap.obj .text: undefined reference to '_fwrite' defaulttrap.obj .text: undefined reference to '_itoa' defaulttrap.obj .text: undefined reference to '_strcat' defaulttrap.obj .text: undefined reference to '_MessageBoxA@16' defaulttrap.obj .text: undefined reference to '_abort' powlasm.obj .text: undefined reference to '_pow' qfloat.obj .text: undefined reference to '_memset' qfloat.obj .text: undefined reference to '_strchr' qfloat.obj .text: undefined reference to '_memmove' strlcpy.obj .text: undefined reference to '_memcpy' xprintf.obj .text: undefined reference to '_localeconv' xprintf.obj .text: undefined reference to '_strtol' xprintf.obj .text: undefined reference to '_wcslen' xprintf.obj .text: undefined reference to '_wctomb' xprintf.obj .text: undefined reference to '_fputc' search Compilation + link time:0.1 sec, Return code: 60 when I attempt to execute the program within wedit i get a dialog box that says "hello.exe is not up-to-date. Rebuild?" If I click yes, nothing happens. If I click no, a dos window pops up saying "C:\lcc\projects\lcc2\hello.exe" Return code -1 Execution time 0.001 seconds Press any key to continue... This continues to happen no matter how many times i compile/rebuild. Any ideas?

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  • Selecting a Java framework for large application w/ only ONE user

    - by Bijan
    I am building a large application that will be hosted on an AWS server. I'm trying to select a web framework for assisting me with code organization, template design, and generally presentation aspects. Here are some points of consideration: Require security/login/user authentication. I may add the ability in the future to allow more than just an administrator to access the web app, but it is not a public facing website. AJAX support would be helpful. There are a couple widgets that I don't want to recreate. One is a tree object, where the user can expand/contract items in the list, can create new branches, add/edit objects. This would be better off in some dynamic view rather than all done in ugly html. Generally, this is just to provide the application with a face for control, management, and monitoring. Having an easier time adding buttons, CSS, AJAX widgets are great additions though, but not the primary purpose. I'm considering: Wicket Spring Seam GWT Stripe and the list goes on, as I'm sure you all know. I originally planned on using GWT, but then started to feel that GWT didn't cover my primary needs. I could be wrong about this, but there seems to be a lot of support for GWT AND Wicket/Spring. All of this 'getting lost in java frameworks' got me thinking outside the java realm for a framework that would suit my needs that was a clear option, like: JRuby/Rails Jython/Django Groovy/Grails Guice (just throwing this in there... I don't clearly understand the main purposes of all these frameworks. It doesn't seem like DInjection is something I need for a single purpose application) Thanks as always. This community makes Googling for esoteric programming information an order of magnitude better.

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  • Daylight saving time - do and don'ts

    - by Oded
    I am hoping to make this question and the answers to it the definitive guide to dealing with daylight saving time, in particular for dealing with the actual change overs. Many systems are dependent on keeping accurate time, the problem is with changes to time due to daylight savings - moving the clock forward or backwards. For instance, one has business rules in an order taking system that depend on the time of the order - if the clock changes, the rules might not be as clear. How should the time of the order be persisted? There is of course an endless number of scenarios - this one is simply an illustrative one. How have you dealt with the daylight saving issue? What assumptions are part of your solution? (looking for context here) As important, if not more so: What did you try that did not work? Why did it not work? I would be interested in programming, OS, data persistence and other pertinent aspects of the issue. General answers are great, but I would also like to see details especially if they are only available on one platform.

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  • Implementing BindingList<T>

    - by EtherealMonkey
    I am trying to learn more about BindingList because I believe that it will help me with a project that I am working on. Currently, I have an object class (ScannedImage) that is a subtype of a class (HashedImage) that subtypes a native .Net object (Image). There is no reason why I couldn't move the two subtypes together. I am simply subtyping an object that I had previously constructed, but I will now be storing my ScannedImage object in an RDB (well, not technically - only the details and probably the thumbnail). Also, the object class has member types that are my own custom types (Keywords). I am using a custom datagridview to present these objects, but am handling all changes to the ScannedImage object with my own code. As you can probably imagine, I have quite a few events to handle that occur in these base types. So, if I changed my object to implement INotifyPropertyChanged, would the object collection (implementing BindingList) receive notifications of changes to the ScannedImage object? Also, if Keywords were to implement INotifyPropertyChanged, would changes be accessible to the BindingList through the ScannedImage object? Sorry if this seems rather newbish. I only recently discovered the BindingList and not having formal training in C# programming - am having a difficult time moving forward with this. Also, if anyone has any good reference material, I would be thankful for links. Obviously, I have perused the MSDN Library. I have found a few good links on the web, but it seems that a lot of people are now using WPF and ObservableCollection. My project is based on Winforms and .Net3.5 framework. TIA

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  • doublechecking: no db-wide 'unicode switch' for sql server in the foreseeable future, i.e. like Orac

    - by user72150
    Hi all, I believe I know the answer to this question, but wanted to confirm: Question Does Sql server (or will it in the foreseeable future), offer a database-wide "unicode switch" which says "store all characters in unicode (UTF-16, UCS-2, etc)", i.e. like Oracle. The Context Our application has provided "CJK" (Chinese-Japanese-Korean) support for years--using Oracle as the db store. Recently folks have been asking for the same support in sql server. We store our db schema definition in xml and generate the vendor-specific definitions (oracle, sql server) using vendor-specific xsl. We can make the change easily. The problem is for upgrades. Generated scripts would need to change the column types for 100+ columns from varchar to nvarchar, varchar(max) to nvarchar(max), etc. These changes require dropping and recreating indexes and foreign keys if the any indexes/fk's exist on the column. Non-trivial. Risky. DB-wide character encodings for us would eliminate programming changes. (I.e. we would not to change the column types from varchar to nvarchar; sql server would correctly store unicode data in varchar columns). I had thought that eventually sql server would "see the light" and allow storing unicode in varchar/clob columns. Evidently not yet. Recap So just to triple check: does mssql offer a database-wide switch for character encoding? Will it in SQL2008R3? or 2010? thanks, bill

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  • Help a C# developer understand: What is a monad?

    - by Charlie Flowers
    There is a lot of talk about monads these days. I have read a few articles / blog posts, but I can't go far enough with their examples to fully grasp the concept. The reason is that monads are a functional language concept, and thus the examples are in languages I haven't worked with (since I haven't used a functional language in depth). I can't grasp the syntax deeply enough to follow the articles fully ... but I can tell there's something worth understanding there. However, I know C# pretty well, including lambda expressions and other functional features. I know C# only has a subset of functional features, and so maybe monads can't be expressed in C#. However, surely it is possible to convey the concept? At least I hope so. Maybe you can present a C# example as a foundation, and then describe what a C# developer would wish he could do from there but can't because the language lacks functional programming features. This would be fantastic, because it would convey the intent and benefits of monads. So here's my question: What is the best explanation you can give of monads to a C# 3 developer? Thanks! (EDIT: By the way, I know there are at least 3 "what is a monad" questions already on SO. However, I face the same problem with them ... so this question is needed imo, because of the C#-developer focus. Thanks.)

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  • Problem with apostrophes and other special characters when using aspell in windows

    - by Loftx
    Hi there, We seem to be having a problem with the spell checker on our content management system where it marks the ve part of We’ve as a misspelling. The spellchecker uses aspell which is called from a script on the server which executes the cmd.exe and uses it to pipe a file into aspell (it's a long winded way I know, but our server side programming langauge (ColdFusion) doesn't support writing to stdin for executables). Aspell is called by executing: c:\windows\system32\cmd.exe /c type d:\path_to_file\file.txt | "C:\Program Files\Aspell\bin\aspell" --lang=en -a Where file.txt contains the text to be spelled e.g. ^Oh have We’ve (the carat is added to prevent piping problems I believe). Aspell then output: @(#) International Ispell Version 3.1.20 (but really Aspell 0.50.3) * * * & ve 62 12: vie, voe, V, v, veg, vet, Be, Ce, be, Ev, E, e, vex, VA, VI, Va, Vi, vi, we, VD, VF, VG, VJ, VP, VT, Vt, vb, vs, DE, De, Fe, GE, Ge, He, IE, Le, ME, Me, NE, Ne, OE, PE, Re, SE, Se, Te, Xe, he, me, re, ye, Ave, Eve, Ive, ave, eve, VAR, var, veer, vier, view, vow However, we have a dev site, with the same version of Aspell, and when the same file is used it outputs with no misspellings. Both servers are running Aspell 0.50.3 on Windows server 2003, but there could be other differences in configuration: @(#) International Ispell Version 3.1.20 (but really Aspell 0.50.3) I'm wondering if the problem is to do with the piping part of the process or something different in the Aspell configuration. Does anyone have any ideas? Cheers, Tom

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  • my MKAnnotationVIew is not showing the title

    - by hydev
    Hi, I am new to iPhone programming and I can't understand why the MKAnnotationView is not showing the title's of my annotation's. Below is the code that is used to display it on the map. - (void)mapView:(MKMapView *)mv didAddAnnotationViews:(NSArray *)views { NSLog(@"Entered didAddAnnotationViews"); MKAnnotationView *annotationView = [views objectAtIndex:0]; id <MKAnnotation> mp = [annotationView annotation]; MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance([mp coordinate], 250, 250); [mv setRegion:region animated:YES]; } Here is where I am defining my annotations: MapPoint *mp = [[MapPoint alloc] initWithCoordinate:[newLocation coordinate] title:[locationTitleField text]]; [mapView addAnnotation:mp]; [mp release]; mp is a class I have created to keep track of all the map points: #import "MapPoint.h" @implementation MapPoint @synthesize coordinate, title; - (id)initWithCoordinate:(CLLocationCoordinate2D)c title:(NSString *)t { [super init]; coordinate = c; [self setTitle:t]; return self; } - (void)dealloc { [title release]; [super dealloc]; } @end I am beginner so go easy, and all help greatly appreciated. Mike

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  • Thumbnail Provider not working

    - by Dan
    I'm trying to write a Windows Explorer thumbnail handler for our custom file type. I've got this working fine for the preview pane, but am having trouble getting it to work for the thumbnails. Windows doesn't even seem to be trying to call the DllGetClassObject entry point. Before I continue, note that I'm using Windows 7 and unmanaged C++. I've registered the following values in the registry: HKCR\CLSID\<my guid> HKCR\CLSID\<my guid>\InprocServer32 (default value being path to my DLL) HKCR\CLSID\<my guid>\InprocServer32\ThreadingModel (value = "Apartment") HKCR\.<my ext>\shellex\{E357FCCD-A995-4576-B01F-234630154E96} (value = my guid) I've also tried using the Win SDK sample, and that doesn't work. And also the sample project in this article (http://www.codemonkeycodes.com/2010/01/11/ithumbnailprovider-re-visited/), and that doesn't work. I'm new to shell programming, so not really sure the best way of debugging this. I've tried attaching the debugger to explorer.exe, but that doesn't seem to work (breakpoints get disabled, and none of my OutputDebugStrings get displayed in the output window). Note that I tried setting the "DesktopProcess" in the registry as described in the WinSDK docs for debugging the shell, but I'm still only seeing one explorer.exe in the task manager - so that "may" be why I can't debug it?? Any help with this would be greatly appreciated! Regards, Dan.

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  • Learning about the low level

    - by Anoners
    I'm interested in learning more about the PC from a lower (machine) level. I graduated from a school which taught us concepts using the Java language which abstracted out that level almost completely. As a result I only learned a bit from the one required assembly language course. In order to cram in ASM and quite a few details about architecture, it was hard to get a very deep picture of what is going on there. At work I focus on unix socket programming in C, so i'm much closer to the hardware now, but I feel I should learn a bit more about what streams really are, how memory management and paging works, what goes on when you call "paint()" on a graphics buffer, etc. I missed out on a lot of this and i'm looking for a good resource to get me started. I've heard a lot about the "Pink Book" by Peter Norton (Programmer's Guide to the IBM PC, Programmer's Guide to inside the PC, etc). It seems like this is on the right track, however the original is quite out dated and the newer ones have had conflicting reviews, with many people saying to stay away from it. I'm not sure what the SO crowd thinks about this book or if they have some suggestions for similar books, online resources, etc that may be good primers for this sort of thing. Any suggestions would be appreciated.

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  • Preventing Processes From Spawning Using .NET Code

    - by Matt
    I remember coming across an article on I think CodeProject quite some time ago regarding an antivirus or antimalware some guy was writing where he hooked into the Windows API to be able to catch whenever a new process was started and was prompting he user before allowing the process to start. I can no longer find the article, and would actually like to be able to implement something like this. Currently, we have a custom browser built on Gecko that we've integrated access restrictions to sites based on our internal employee security levels, etc. We prevent any other browser from running with a timer and a call to Process.GetProcessesByName() from a list of the browsers we don't allow. What we want to accomplish is, instead of just blocking these browsers, where there is a small delay between the other browser starting and it being killed by our service, we'd like to be able to display a dialog instead of the process launching at all, explaining that the program isn't in the allowed list. This way, we can generate a list of "allowed" processes and just block everything else (we haven't yet had a problem with outside apps being installed, but you can never be too careful). Unfortunately, we don't do much Windows API programming from C#, so I'm not sure where to begin looking for what calls we need to hook. Even just a starting point of what to read up on would be helpful.

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  • TLS with SNI in Java clients

    - by ftrotter
    There is an ongoing discussion on the security and trust working group for NHIN Direct regarding the IP-to-domain mapping problem that is created with traditional SSL. If an HISP (as defined by NHIN Direct) wants to host thousands of NHIN Direct "Health Domains" for providers, then it will an "artificially inflated cost" to have to purchase an IP for each of those domains. Because Apache and OpenSSL have recently released TLS with support for the SNI extension, it is possible to use SNI as a solution to this problem on the server side. However, if we decide that we will allow server implementations of the NHINDirect transport layer to support TLS+SNI, then we must require that all clients support SNI too. OpenSSL based clients should do this by default and one could always us stunnel to implement an TLS+SNI aware client to proxy if your given programming language SSL implementation does not support SNI. It appears that native Java applications using OpenJDK do not yet support SNI, but I cannot get a straight answer out of that project. I know that there are OpenSSL Java libraries available but I have no idea if that would be considered viable. Can you give me a "state of the art" summary of where TLS+SNI support is for Java clients? I need a Java implementers perspective on this.

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  • Pros & Cons of Google App Engine

    - by Rishi
    Pros & Cons of Google App Engine [An Updated List 21st Aug 09] Help me Compile a List of all the Advantages & Disadvantages of Building an Application on the Google App Engine Pros: 1) No Need to buy Servers or Server Space (no maintenance). 2) Makes solving the problem of scaling much easier. Cons: 1) Locked into Google App Engine ?? 2)Developers have read-only access to the filesystem on App Engine. 3)App Engine can only execute code called from an HTTP request (except for scheduled background tasks). 4)Users may upload arbitrary Python modules, but only if they are pure-Python; C and Pyrex modules are not supported. 5)App Engine limits the maximum rows returned from an entity get to 1000 rows per Datastore call. 6)Java applications may only use a subset (The JRE Class White List) of the classes from the JRE standard edition. 7)Java applications cannot create new threads. Known Issues!! http://code.google.com/p/googleappengine/issues/list Hard limits Apps per developer - 10 Time per request - 30 sec Files per app - 3,000 HTTP response size - 10 MB Datastore item size - 1 MB Application code size - 150 MB Pro or Con? App Engine's infrastructure removes many of the system administration and development challenges of building applications to scale to millions of hits. Google handles deploying code to a cluster, monitoring, failover, and launching application instances as necessary. While other services let users install and configure nearly any *NIX compatible software, App Engine requires developers to use Python or Java as the programming language and a limited set of APIs. Current APIs allow storing and retrieving data from a BigTable non-relational database; making HTTP requests; sending e-mail; manipulating images; and caching. Most existing Web applications can't run on App Engine without modification, because they require a relational database.

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  • Project Euler: Programmatic Optimization for Problem 7?

    - by bmucklow
    So I would call myself a fairly novice programmer as I focused mostly on hardware in my schooling and not a lot of Computer Science courses. So I solved Problem 7 of Project Euler: By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13. What is the 10001st prime number? I managed to solve this without problem in Java, but when I ran my solution it took 8 and change seconds to run. I was wondering how this could be optimized from a programming standpoint, not a mathematical standpoint. Is the array looping and while statements the main things eating up processing time? And how could this be optimized? Again not looking for a fancy mathematical equation..there are plenty of those in the solution thread. SPOILER My solution is listed below. public class PrimeNumberList { private ArrayList<BigInteger> primesList = new ArrayList<BigInteger>(); public void fillList(int numberOfPrimes) { primesList.add(new BigInteger("2")); primesList.add(new BigInteger("3")); while (primesList.size() < numberOfPrimes){ getNextPrime(); } } private void getNextPrime() { BigInteger lastPrime = primesList.get(primesList.size()-1); BigInteger currentTestNumber = lastPrime; BigInteger modulusResult; boolean prime = false; while(!prime){ prime = true; currentTestNumber = currentTestNumber.add(new BigInteger("2")); for (BigInteger bi : primesList){ modulusResult = currentTestNumber.mod(bi); if (modulusResult.equals(BigInteger.ZERO)){ prime = false; break; } } if(prime){ primesList.add(currentTestNumber); } } } public BigInteger get(int primeTerm) { return primesList.get(primeTerm - 1); } }

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  • Interface Casting vs. Class Casting

    - by Legatou
    I've been led to believe that casting can, in certain circumstances, become a measurable hindrance on performance. This may be moreso the case when we start dealing with incoherent webs of nasty exception throwing\catching. Given that I wish to create more correct heuristics when it comes to programming, I've been prompted to ask this question to the .NET gurus out there: Is interface casting faster than class casting? To give a code example, let's say this exists: public interface IEntity { IParent DaddyMommy { get; } } public interface IParent : IEntity { } public class Parent : Entity, IParent { } public class Entity : IEntity { public IParent DaddyMommy { get; protected set; } public IParent AdamEve_Interfaces { get { IEntity e = this; while (this.DaddyMommy != null) e = e.DaddyMommy as IEntity; return e as IParent; } } public Parent AdamEve_Classes { get { Entity e = this; while (this.DaddyMommy != null) e = e.DaddyMommy as Entity; return e as Parent; } } } So, is AdamEve_Interfaces faster than AdamEve_Classes? If so, by how much? And, if you know the answer, why?

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  • Java Robot key activity seems to stop working while certain software is running

    - by Mike Turley
    I'm writing a Java application to automate character actions in an online game overnight (specifically, it catches fish in Final Fantasy XI). The app makes heavy use of java's Robot class both for emulating user keyboard input and for detecting color changes on certain parts of the screen. It also uses multithreading and a swing GUI. The application seems to work perfectly when I test it without the game running, just using screenshots to trigger the apps responses into notepad. But for some reason, when I actually launch FFXI and start the program, all of my keyboard and mouse manipulations just stop working altogether. The program is still running, and the Robot class is still able to read pixel colors. But Robot.keyPress, Robot.keyRelease, Robot.mouseMove, Robot.mousePress and Robot.mouseRelease all do nothing. It's the strangest thing-- to test it, I wrote a simple loop that just keeps typing letters, and focused notepad. I'd then start the game, refocus notepad, and it would do nothing. Then I'd exit the game, and it'd start working again immediately. Has anyone else come across something like this, where specific software will stop certain functions of java from working? Also, to make this more interesting-- Last year I wrote a very similar program using the same classes and programming techniques to automate healing a party in the game as they fight. Last year, this program worked perfectly. After running into these problems I dug up that old program, ran it without making any changes, and found that it too was having the same problems. The only differences between now and when it was working: I was running Windows Vista and now I'm running Windows 7, and several new Java versions as well as FFXI versions have been released. What the hell is going on? (if anyone needs to see my source code, email me at [email protected]. I'm trying to keep it to myself.)

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  • Scheme Infix to Postfix

    - by Cody
    Let me establish that this is part of a class assignment, so I'm definitely not looking for a complete code answer. Essentially we need to write a converter in Scheme that takes a list representing a mathematical equation in infix format and then output a list with the equation in postfix format. We've been provided with the algorithm to do so, simple enough. The issue is that there is a restriction against using any of the available imperative language features. I can't figure out how to do this in a purely functional manner. This is our fist introduction to functional programming in my program. I know I'm going to be using recursion to iterate over the list of items in the infix expression like such. (define (itp ifExpr) ( ; do some processing using cond statement (itp (cdr ifExpr)) )) I have all of the processing implemented (at least as best I can without knowing how to do the rest) but the algorithm I'm using to implement this requires that operators be pushed onto a stack and used later. My question is how do I implement a stack in this function that is available to all of the recursive calls as well?

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  • How does one properly redefine self while avoiding the "Multiple methods named ..." warning?

    - by Elise van Looij
    In Apple's The Objective-C Programming Language: Defining a Class the section named "Redifining self" recommends that that class methods allocate and return instances use 'self' only to allocate an instance and then refer only to that instance. Thus, I have a number of subclasses, that have class methods along the lines of: + (id)scrollViewWithFrame: (NSRect)rectFrame { id newInstance = [[[self alloc] initWithFrame:rectFrame] autorelease]; [newInstance setHasHorizontalScroller: YES]; [newInstance setHasVerticalScroller: YES]; [newInstance setBorderType: NSNoBorder]; [newInstance setAutoresizingMask: (NSViewWidthSizable | NSViewHeightSizable)]; return newInstance; } The above is, of course, a subclass of NSScrollView. Unfortunately, Xcode 3.x all these NSView subclasses now raise warnings: "Warning: Multiple methods named '-setAutoresizingMask' found". I believe it has something to do with GCC 4.2, the settings of which I have not changed. The warning is correct, of course, since NSView and its various subclasses all implement setAutoresizingMask, but it is also unnecessary. Since they're only warnings, I ignore them but there is a risk that in between the thirty or so unnecessary ones, a really useful warning lurks which I simply don't see. So, what to do? I do want to adhere to good coding practices and I want to build warning-free apps -- how can I do both?

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  • Which of these is pythonic? and Pythonic vs. Speed

    - by Kashyap Nadig
    Hi! I'm new to python and just wrote this module level function: def _interval(patt): """ Converts a string pattern of the form '1y 42d 14h56m' to a timedelta object. y - years (365 days), M - months (30 days), w - weeks, d - days, h - hours, m - minutes, s - seconds""" m = _re.findall(r'([+-]?\d*(?:\.\d+)?)([yMwdhms])', patt) args = {'weeks': 0.0, 'days': 0.0, 'hours': 0.0, 'minutes': 0.0, 'seconds': 0.0} for (n,q) in m: if q=='y': args['days'] += float(n)*365 elif q=='M': args['days'] += float(n)*30 elif q=='w': args['weeks'] += float(n) elif q=='d': args['days'] += float(n) elif q=='h': args['hours'] += float(n) elif q=='m': args['minutes'] += float(n) elif q=='s': args['seconds'] += float(n) return _dt.timedelta(**args) My issue is with the for loop here i.e the long if elif block, and was wondering if there is a more pythonic way of doing it. So I re-wrote the function as: def _interval2(patt): m = _re.findall(r'([+-]?\d*(?:\.\d+)?)([yMwdhms])', patt) args = {'weeks': 0.0, 'days': 0.0, 'hours': 0.0, 'minutes': 0.0, 'seconds': 0.0} argsmap = {'y': ('days', lambda x: float(x)*365), 'M': ('days', lambda x: float(x)*30), 'w': ('weeks', lambda x: float(x)), 'd': ('days', lambda x: float(x)), 'h': ('hours', lambda x: float(x)), 'm': ('minutes', lambda x: float(x)), 's': ('seconds', lambda x: float(x))} for (n,q) in m: args[argsmap[q][0]] += argsmap[q][1](n) return _dt.timedelta(**args) I tested the execution times of both the codes using timeit module and found that the second one took about 5-6 seconds longer (for the default number of repeats). So my question is: 1. Which code is considered more pythonic? 2. Is there still a more pythonic was of writing this function? 3. What about the trade-offs between pythonicity and other aspects (like speed in this case) of programming? p.s. I kinda have an OCD for elegant code. EDITED _interval2 after seeing this answer: argsmap = {'y': ('days', 365), 'M': ('days', 30), 'w': ('weeks', 1), 'd': ('days', 1), 'h': ('hours', 1), 'm': ('minutes', 1), 's': ('seconds', 1)} for (n,q) in m: args[argsmap[q][0]] += float(n)*argsmap[q][1]

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