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• What's best choice career-wise, to know a little about a lot or a lot about a little?

  - by nimo

  I work as a developer at a rather small company and we are providing a web application that is used by a big base of customers. Because we are so small everyone have to be able to do a lot of different tasks. It ranges from advanced support, developing the product (programming: c/c++, c#, php, sql, javascript, html, css), handle network configuration and network related issues and even sometimes go on sales meetings with potential customers. My concern is that I don't really specialize in any specific area. I know and learn little about a lot. I have graduated from school two years ago and this is my first real employment and when I look at other positions out there they always require so and so many years of experience in a specific area (for example 5 years of C#). For me to get that kind of specialized experience will be really hard at my current job. My question for you is what is, in your opinion, best choice career-wise, to know a little about a lot or a lot about a little? What path did you take? pros and cons that comes with that choice.

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• Looking for a good C++/.net

  - by Michael Minerva

  I have recently started to feel that I need to greatly improve my C++ skills especially in the realm of .net. I graduated from a good four year university with a degree in computer science about 9 months ago and I have since been doing full time contract work for a small software company in my local area. Most of my work has been done using Java/lisp/cocoa/XML and before that most of my programming in my senior year was in java/C#. I did a decent amount of C++ in my Sophomore year and in my free time before that but I feel that my general knowledge of C++/.net is very lacking for the opportunities that are now coming my way. Can anyone recommend a good book that could help me get up too speed? I feel I do not need a very basic introduction to C++ but something that covers the fundamentals of .net would be good for me. So basically what I need is a book or books that would be good for a .net novice and a C++ developer who is just beyond novice. Also, a book that would help bein an interview by giving me a conversional understanding of C++ would be great. Thanks a lot!.

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• C++ BigInt multiplication conceptual problem

  - by Kapo

  I'm building a small BigInt library in C++ for use in my programming language. The structure is like the following: short digits[ 1000 ]; int len; I have a function that converts a string into a bigint by splitting it up into single chars and putting them into digits. The numbers in digits are all reversed, so the number 123 would look like the following: digits[0]=3 digits[1]=3 digits[2]=1 I have already managed to code the adding function, which works perfectly. It works somewhat like this: overflow = 0 for i ++ until length of both numbers exceeded: add numberA[ i ] to numberB[ i ] add overflow to the result set overflow to 0 if the result is bigger than 10: substract 10 from the result overflow = 1 put the result into numberReturn[ i ] (Overflow is in this case what happens when I add 1 to 9: Substract 10 from 10, add 1 to overflow, overflow gets added to the next digit) So think of how two numbers are stored, like those: 0 | 1 | 2 --------- A 2 - - B 0 0 1 The above represents the digits of the bigints 2 (A) and 100 (B). - means uninitialized digits, they aren't accessed. So adding the above number works fine: start at 0, add 2 + 0, go to 1, add 0, go to 2, add 1 But: When I want to do multiplication with the above structure, my program ends up doing the following: Start at 0, multiply 2 with 0 (eek), go to 1, ... So it is obvious that, for multiplication, I have to get an order like this: 0 | 1 | 2 --------- A - - 2 B 0 0 1 Then, everything would be clear: Start at 0, multiply 0 with 0, go to 1, multiply 0 with 0, go to 2, multiply 1 with 2 How can I manage to get digits into the correct form for multiplication? I don't want to do any array moving/flipping - I need performance!

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• SQL Server 2008 R2

  - by kevchadders

  Hi all, I heard on the grapevine that Microsoft will be releasing SQL Server 2008 R2 within a year. Though I initially thought this was a patch for the just released 2008 version, I realised that it’s actually a completely different version that you would have to pay for. (Am I correct, if you had SQL Server 2008, would you have to pay again if you wanted to upgrade to 2008 R2?) If you’re already running SQL Server 2008, would you say it’s still worth the upgrade? Or does it depend on the size of your company and current setup. For what I’ve initially read, I do get the impression that this version would be more useful for the very high end hardware setup where you want to have very good scalability. With regard to programming, is there any extra enhancements/support in there which you’re aware of that will significantly help .NET Products/Web Development? Initially found a couple of links on it, but I was wondering if anyone had anymore info to share on subject as I couldn’t find nothing on SO about it? Thanks. New SQL Server R2 Microsoft Link on it. Microsoft SQL 2008 R2 EDIT: More information based on the Express Edition One very interesting thing about SQL Server 2008 R2 concerns the Express edition. Previous express versions of SQL Server Express had a database size limit of 4GB. With SQL Server Express 2008 R2, this has now been increased to 10GB !! This now makes the FREE express edition a much more viable option for small & medium sized applications that are relatively light on database requirements. Bear in mind, that this limit is per database, so if you coded your application cleverly enough to use a separate database for historical/archived data, you could squeeze even more out of it! For more information, see here: http://blogs.msdn.com/sqlexpress/archive/2010/04/21/database-size-limit-increased-to-10gb-in-sql-server-2008-r2-express.aspx

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• Perl TCP Server handling multiple Client connections

  - by Matt

  I'll preface this by saying I have minimal experience with both Perl and Socket programming, so I appreciate any help I can get. I have a TCP Server which needs to handle multiple Client connections simultaneously and be able to receive data from any one of the Clients at any time and also be able to send data back to the Clients based on information it's received. For example, Client1 and Client2 connect to my Server. Client2 sends "Ready", the server interprets that and sends "Go" to Client1. The following is what I have written so far: my $sock = new IO::Socket::INET { LocalHost => $host, // defined earlier in code LocalPort => $port, // defined earlier in code Proto => 'tcp', Listen => SOMAXCONN, Reuse => 1, }; die "Could not create socket $!\n" unless $sock; while ( my ($new_sock,$c_addr) = $sock->accept() ) { my ($client_port, $c_ip) = sockaddr_in($c_addr); my $client_ipnum = inet_ntoa($c_ip); my $client_host = ""; my @threads; print "got a connection from $client_host", "[$client_ipnum]\n"; my $command; my $data; while ($data = <$new_sock>) { push @threads, async \&Execute, $data; } } sub Execute { my ($command) = @_; // if($command) = "test" { // send "go" to socket1 print "Executing command: $command\n"; system($command); } I know both of my while loops will be blocking and I need a way to implement my accept command as a thread, but I'm not sure the proper way of writing it.

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• Java side scrolling game on android

  - by hanesjw

  I'm trying to make an easy side scrolling game just to learn the ropes of game programming on android. I came up with a solution of how to make it but I don't really think it is the most elegant solution. I wanted to get some different ideas on how to implement my game, as I really have no other solution right now. Here is a quick explanation of how it works.. I basically have blocks or objects fall from the top of the screen. The blocks are defined from a pre-defined string I create using a custom 'map-editor'. I create all the blocks at compile time, position them on or off the screen and simply increment their coordinates with each iteration of the gameloop. It is actually done a little bit better then that, but that gives a short easy explanation on the basic idea. I heard from a few people that instead of incrementing each block position, have the blocks stay there and simply change the viewable area. That makes sense, but I have no idea how to do it. Can anyone share some ideas or links on how I can implement something like this? I know my current solution isn't the greatest. Thanks!

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• Is it getting to be time for C# to support compile-time macros?

  - by Robert Rossney

  Thus far, Microsoft's C# team has resisted adding formal compile-time macro capabilities to the language. There are aspects of programming with WPF that seem (to me, at least) to be creating some compelling use cases for macros. Dependency properties, for instance. It would be so nice to just be able to do something like this: [DependencyProperty] public string Foo { get; set; } and have the body of the Foo property and the static FooProperty property be generated automatically at compile time. Or, for another example an attribute like this: [NotifyPropertyChanged] public string Foo { get; set; } that would make the currently-nonexistent preprocessor produce this: private string _Foo; public string Foo { get { return _Foo; } set { _Foo = value; OnPropertyChanged("Foo"); } } You can implement change notification with PostSharp, and really, maybe PostSharp is a better answer to the question. I really don't know. Assuming that you've thought about this more than I have, which if you've thought about it at all you probably have, what do you think? (This is clearly a community wiki question and I've marked it accordingly.)

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• What is a simple way to add a timer to a method

  - by John

  The following is in C#. I'm trying to do something very simple (I think). I have a method that loads an XML document XDocument doc = XDocument.Load(uri); , but I don't want to tie up pc resources if there are issues (connectivity, document size, etc.). So I'd like to be able to add a timeout variable that will cut the method off after a given number of seconds. I'm a newbie when it comes to asynchronous programming and find it confusing that there are so many examples written so many different ways . . . and none of them appear simple. I'd like a simple solution, if possible. Here's my thoughts so far on possible solution paths: 1) A method that wraps the existing load public XDocument LoadXDocument(string uri, int timeout){ //code } 2) A wrapper, but as an extension method XDocument doc = XDocument.LoadWithTimeout(string uri, int timeout); 3) A generic extension method. Object obj = SomeStaticClass.LoadWithTimeout(??? method, int timeout); 3), on its face seems really nice, because it would mean being able to generically add timeouts to many different method calls and not specifically tied to one type of object, but I suspect that it is either i)impossible or ii) very difficult. Please assist. Thanks.

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• Avoiding duplication in setting properties on the task in Rake tasks

  - by Stray

  I have a bunch of rake building tasks. They each have unique input / output properties, but the majority of the properties I set on the tasks are the same each time. Currently I'm doing that via simple repetition like this: task :buildThisModule => "bin/modules/thisModule.swf" mxmlc "bin/modules/thisModule.swf" do |t| t.input = "src/project/modules/ThisModule.as" t.prop1 = value1 t.prop2 = value2 ... (And many more property=value sets that are the same in each task) end task :buildThatModule => "bin/modules/thatModule.swf" mxmlc "bin/modules/thatModule.swf" do |t| t.input = "src/project/modules/ThatModule.as" t.prop1 = value1 t.prop2 = value2 ... (And many more property=value sets that are the same in each task) end In my usual programming headspace I'd expect to be able to break out the population of the recurring task properties to a re-usable function. Is there a rake analogy for this? Some way I can have a single function where the shared properties are set on any task? Something equivalent to: task :buildThisModule => "bin/modules/thisModule.swf" mxmlc "bin/modules/thisModule.swf" do |t| addCommonTaskParameters(t) t.input = "src/project/modules/ThisModule.as" end task :buildThatModule => "bin/modules/thatModule.swf" mxmlc "bin/modules/thatModule.swf" do |t| addCommonTaskParameters(t) t.input = "src/project/modules/ThatModule.as" end Thanks.

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• Should I learn to code?

  - by saltcod

  Hi All, This is more of a philosophical question than a technical one, but I’d like some opinions on it, and I think that there are many others in my position that would benefit. My issue is that I don’t really have time to learn how to code. I know, I know… no one has time anymore, but please hear me out. Since learning to use Drupal about 2 years ago I’ve been involved with several projects wherein I’ve become the default quasi-developer, front-end designer, site manager, and system administrator. What I’ve found is that I can produce fairly nice, feature rich Drupal sites with the wealth of contrib. modules out there (Views, CCK, image handling, etc….). BUT! I can’t code. I know enough PHP to insert something into a block, or re-word a string, but that’s about it. I still don’t really even know how arrays work. My question Succinctly, my question is: Given the time that I have available for all of this stuff – in addition to a full-time job and regular life – am I better off trying to become more expert at the front-end stuff, or should I just learn PHP already? Pros 1. If a project doesn’t use Drupal, I’ll know enough PHP to be able to participate. 2. Learning PHP would help my Drupal development too 3. Learning PHP would make front-end theming easier 4. Learning PHP should give me that missing background in programming – and should allow me to learn other languages in the future Cons 1. At 28, I know I’m not too old to learn anything. But am I too old to become ‘good’? 2. Am I better off getting better and better at front-end UX work? 3. Am I better off farming out the PHP work? Suggestions from coders welcome! Thanks Terry

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• How to amend return value design in OO manner?

  - by FrontierPsycho

  Hello. I am no newb on OO programming, but I am faced with a puzzling situation. I have been given a program to work on and extend, but the previous developers didn't seem that comfortable with OO, it seems they either had a C background or an unclear understanding of OO. Now, I don't suggest I am a better developer, I just think that I can spot some common OO errors. The difficult task is how to amend them. In my case, I see a lot of this: if (ret == 1) { out.print("yadda yadda"); } else if (ret == 2) { out.print("yadda yadda"); } else if (ret == 3) { out.print("yadda yadda"); } else if (ret == 0) { out.print("yadda yadda"); } else if (ret == 5) { out.print("yadda yadda"); } else if (ret == 6) { out.print("yadda yadda"); } else if (ret == 7) { out.print("yadda yadda"); } ret is a value returned by a function, in which all Exceptions are swallowed, and in the catch blocks, the above values are returned explicitly. Oftentimes, the Exceptions are simply swallowed, with empty catch blocks. It's obvious that swalllowing exceptions is wrong OO design. My question concerns the use of return values. I believe that too is wrong, however I think that using Exceptions for control flow is equally wrong, and I can't think of anything to replace the above in a correct, OO manner. Your input, please?

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• Where do you use Java code? Trouble sending .jar files

  - by leigero

  Apologies for the generic nature of this question. I have been learning Java for a few months now, and I've created a few simple projects which have some functionality. I wanted to send the projects to a friend and I'm running into countless errors and struggles. Passing a .jar file is causing "Main class not found" errors when they try to open it. I tried using third party software to wrap the .jar files into an .exe file and the same errors still persist. Beyond that, I'm convinced that passing around .jar files wrapped into .exe files via third party software is NOT how Java was intended to be used. I've read two books on Java and they all talk about structuring the language, but I'm confused about WHERE I'm supposed to be using this code because it has become painfully obvious that it is NOT intended to be passed around in file format. Is this a server programming language? Used on the back end of websites mainly? I'm not sure where one would be using the code written in Java.

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• CreateProcessWithLogonW : unable to start process

  - by Vivek

  Hi I am completely new to programming. And please someone help me. I am trying to start a pocess from a service. I need to start the new process by prompting user to enter admin credentials. I was trying to use CreateProcessWithLogonW(). Am I using the right function. I tried to give input username, password, domain as localhost. I gave full pathe to the .exe file that i need to start. Here is the piece of code. CreateProcessWithLogonW(L"Administrator", L"localhost", L"password", 0, NULL, L"c:\myupdates\myapp.exe", NORMAL_PRIORITY_CLASS | CREATE_CONSOLE, NULL, NULL, &si, &pi); Si.cb = sizeof(si); Si.lpDesktop = L"winsta0\\default"; But the process never started. Can you guys tell me what I am doing wrong. And what do I need to do to promt user to enter credentials of administrator instead of hardcoding it.

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• Python vs all the major professional languages [closed]

  - by Matt

  I've been reading up a lot lately on comparisons between Python and a bunch of the more traditional professional languages - C, C++, Java, etc, mainly trying to find out if its as good as those would be for my own purposes. I can't get this thought out of my head that it isn't good for 'real' programming tasks beyond automation and macros. Anyway, the general idea I got from about two hundred forum threads and blog posts is that for general, non-professional-level progs, scripts, and apps, and as long as it's a single programmer (you) writing it, a given program can be written quicker and more efficiently with Python than it could be with pretty much any other language. But once its big enough to require multiple programmers or more complex than a regular person (read: non-professional) would have any business making, it pretty much becomes instantly inferior to a million other languages. Is this idea more or less accurate? (I'm learning Python for my first language and want to be able to make any small app that I want, but I plan on learning C eventually too, because I want to get into driver writing eventually. So I've been trying to research each ones strengths and weaknesses as much as I can.) Anyway, thanks for any input

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• What's the best approach for getting into VS2010, C# 4, and WPF if my background is in C++/MFC

  - by Canacourse

  All my past programming experience has been in C++ on VS2003/8, Mostly service based and completely self taught. 2 Years ago I had to create my first real GUI app and (Foolishly) choose MFC. I got the app working but it took a long time & was a bit of a nightmare to learn MCF (and its many shortcomings) but I ended up with a reliable workable app which was difficult to change or extend. Again I have to create another GUI app more complex than the first and again this will be created from scratch and will only ever be used on windows. I had put off learning C# for a long time but not wishing to re-visit MFC have decided that the new application with be birthed in VS2010 and WPF 4 will be the midwife. Trying to avoid the several expensive (Time wise) mistakes I made previously. Im looking for for good books/tutorials on the current versions of C# 4 & WPF 4 and also general advice on the best approach. The application will do several things one of them would persisting info in a SQL DB. So Im thinking LINQ for that? Please chip in...

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• C++: Copy contructor: Use Getters or access member vars directly?

  - by cbrulak

  Have a simple container class: public Container { public: Container() {} Container(const Container& cont) //option 1 { SetMyString(cont.GetMyString()); } //OR Container(const Container& cont) //option 2 { m_str1 = cont.m_str1; } public string GetMyString() { return m_str1;} public void SetMyString(string str) { m_str1 = str;} private: string m_str1; } So, would you recommend this method or accessing the member variables directly? In the example, all code is inline, but in our real code there is no inline code. Update (29 Sept 09): Some of these answers are well written however they seem to get missing the point of this question: this is simple contrived example to discuss using getters/setters vs variables initializer lists or private validator functions are not really part of this question. I'm wondering if either design will make the code easier to maintain and expand. Some ppl are focusing on the string in this example however it is just an example, imagine it is a different object instead. I'm not concerned about performance. we're not programming on the PDP-11

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• Creating serializeable unique compile-time identifiers for arbitrary UDT's.

  - by Endiannes

  I would like a generic way to create unique compile-time identifiers for any C++ user defined types. for example: unique_id<my_type>::value == 0 // true unique_id<other_type>::value == 1 // true I've managed to implement something like this using preprocessor meta programming, the problem is, serialization is not consistent. For instance if the class template unique_id is instantiated with other_type first, then any serialization in previous revisions of my program will be invalidated. I've searched for solutions to this problem, and found several ways to implement this with non-consistent serialization if the unique values are compile-time constants. If RTTI or similar methods, like boost::sp_typeinfo are used, then the unique values are obviously not compile-time constants and extra overhead is present. An ad-hoc solution to this problem would be, instantiating all of the unique_id's in a separate header in the correct order, but this causes additional maintenance and boilerplate code, which is not different than using an enum unique_id{my_type, other_type};. A good solution to this problem would be using user-defined literals, unfortunately, as far as I know, no compiler supports them at this moment. The syntax would be 'my_type'_id; 'other_type'_id; with udl's. I'm hoping somebody knows a trick that allows implementing serialize-able unique identifiers in C++ with the current standard (C++03/C++0x), I would be happy if it works with the latest stable MSVC and GNU-G++ compilers, although I expect if there is a solution, it's not portable.

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• Monads with Join() instead of Bind()

  - by MathematicalOrchid

  Monads are usually explained in turns of return and bind. However, I gather you can also implement bind in terms of join (and fmap?) In programming languages lacking first-class functions, bind is excruciatingly awkward to use. join, on the other hand, looks quite easy. I'm not completely sure I understand how join works, however. Obviously, it has the [Haskell] type join :: Monad m = m (m x) - m x For the list monad, this is trivially and obviously concat. But for a general monad, what, operationally, does this method actually do? I see what it does to the type signatures, but I'm trying to figure out how I'd write something like this in, say, Java or similar. (Actually, that's easy: I wouldn't. Because generics is broken. ;-) But in principle the question still stands...) Oops. It looks like this has been asked before: Monad join function Could somebody sketch out some implementations of common monads using return, fmap and join? (I.e., not mentioning >>= at all.) I think perhaps that might help it to sink in to my dumb brain...

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• a simple program that counts and sums digits. How can I make it work?

  - by user1710386

  So I've to write a simple program(that loops) where you can enter an int and it spews out the number count and the sum of the numbers. Since I am such a tard when it comes to programming, I just scavanged the code online and tried to piece it together. I guess the sum block screws with n, but I am not really sure. Anyway, I would really appreciate it if somebody could point out mistakes and show me how can I make it work. #include <iostream> using namespace std; int main() { while(1) { int i,p,n,sum=0; //sum block cout<<"enter an int: "; cin>>n; { while(n!=0) { p=n % 10; sum+=p; n=n/10; } cout<<"int digit sum: "<<sum <<endl; } { int count = 0; while(n) { n /= 10; ++count; } cout <<"number of digits: " << count << '\n';} } }

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• Seperating two graphs based on connectivity and coordinates

  - by martin

  I would like to separate existing data of vertices and edges into two or more graphs that are not connected. I would like to give the following as example: Imagine two hexagons on top of each other but are lying in different Z. Hexagon 1 has the following vertices A(0,0,1), B(1,0,2), C(2,1,2), D(1,2,1), E(0,2,1), F(-1,2,1). The connectivity is as following: A-B, B-C, C-D, D-E, E-F, F-A. This part of Graph 1 as all the vertices are connected in this layer. Hexagon2 has the following vertices A1(0,0,6), B1(1,0,7), C1(2,1,7), D1(1,2,8), E1(0,2,7), F1(-1,2,6). The connectivity is as following: A1-B1, B1-C1, C1-D1, D1-E1, E1-F1, F1-A1. This is part of Graph 2 My data is in the following form: list of Vertices and list of Edges that i can form graphs with. I would like to eliminate graph 2 and give only vertices and connectivity of graph 1 to polygon determination part of my algorithm. My real data contains around 1000 connected polygons as graph 1 and around 100 (much larger in area) polygons as graph 2. I would like to eliminate graph 2. I am programming this in python. Thanks in advance.

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• MySQL + Joomla + remote c# access

  - by Jimmy

  Hello, I work on a Joomla web site, installed on a MySQL database and running on IIS7. It's all working fine. I now need to add functionality that lets (Joomla-)registered users change some configuration data. Though I haven't done this yet, it looks straightforward enough to do with Joomla. The data is private so all external access will be done through HTTPS. I also need an existing c# program, running on another machine, to read that configuration data. Sure enough, this data access needs to be as fast as possible. The data will be small (and filtered by query), but the latency should be kept to a minimum. A short-term, client-side cache (less than a minute, in case a user updates his configuration data) seems like a good idea. I have done practically zero database/asp programming so far, so what's the best way of doing that last step? Should the c# program access the database 'directly' (using what? LINQ?) or setup some sort of Facade (SOAP?) service? If a service should be used, should it be done through Joomla or with ASP on IIS? Thanks

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• A generic C++ library that provides QtConcurrent functionality?

  - by Lucas

  QtConcurrent is awesome. I'll let the Qt docs speak for themselves: QtConcurrent includes functional programming style APIs for parallel list processing, including a MapReduce and FilterReduce implementation for shared-memory (non-distributed) systems, and classes for managing asynchronous computations in GUI applications. For instance, you give QtConcurrent::map() an iterable sequence and a function that accepts items of the type stored in the sequence, and that function is applied to all the items in the collection. This is done in a multi-threaded manner, with a thread pool equal to the number of logical CPU's on the system. There are plenty of other function in QtConcurrent, like filter(), filteredReduced() etc. The standard CompSci map/reduce functions and the like. I'm totally in love with this, but I'm starting work on an OSS project that will not be using the Qt framework. It's a library, and I don't want to force others to depend on such a large framework like Qt. I'm trying to keep external dependencies to a minimum (it's the decent thing to do). I'm looking for a generic C++ framework that provides me with the same/similar high-level primitives that QtConcurrent does. AFAIK boost has nothing like this (I may be wrong though). boost::thread is very low-level compared to what I'm looking for. I know C# has something very similar with their Parallel Extensions so I know this isn't a Qt-only idea. What do you suggest I use?

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• Android app with library can't find the library.apk

  - by Dean Schulze

  I'm trying to get the FinchVideo example from the Programming Android book to work. It uses the FinchWelcome library. I've set up FinchWelcome as a Library and in the FinchVideo application I have checked the FinchWelcome library in Properties - Android. When I try to run FinchVideo in the emulator it complains that it cannot find FinchWelcome.apk (output below). I'm building for Android 4.0.3. While Googling for this problem I've found that a lot of people have this problem with Android apps that use libraries. No one seems to have found a solution that works consistently, though. None of the Android books I've seen even talk about how to download libraries. What is the proper way to handle libraries in Android applications? Is this a bug in the Eclipse ADT? Thanks. [FinchVideo] Installing FinchVideo.apk... [FinchVideo] Success! [FinchWelcome] Could not find FinchWelcome.apk! [FinchVideo] Starting activity com.oreilly.demo.pa.finchvideo.FinchVideoActivity on device emulator-5554

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• Generic applet style system for publishing mathematics demonstrations?

  - by Alex

  Anyone who's tried to study mathematics using online resources will have come across these Java applets that demonstrate a particular mathematical idea. Examples: http://www.math.ucla.edu/~tao/java/Mobius.html http://www.mathcs.org/java/programs/FFT/index.html I love the idea of this interactive approach because I believe it is very helpful in conveying mathematical principles. I'd like to create a system for visually designing and publishing these 'mathlets' such that they can be created by teachers with little programming experience. So in order to create this app, i'll need a GUI and a 'math engine'. I'll probably be working with .NET because thats what I know best and i'd like to start experimenting with F#. Silverlight appeals to me as a presentation framework for this project (im not worried about interoperability right now). So my questions are: does anything like this exist already in full form? are there any GUI frameworks for displaying mathematical objects such as graphs & equations? are there decent open source libraries that exposes a mathematical framework (Math.NET looks good, just wondering if there is anything else out there) is there any existing work on taking mathematical models/demos built with maple/matlab/octave/mathematica etc and publishing them to the web?

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• Reason for socket.error

  - by August Flanagan

  Hi, I am a complete newbie when it comes to python, and programming in general. I've been working on a little webapp for the past few weeks trying to improve my coding chops. A few days ago my laptop was stolen so I went out and got a new MacBook Pro. Thank God I had everything under subversion control. The problem is now that I am on my new machine a script that I was running has stopped working and I have no idea why. This is really the only part of what I have been writing that I borrowed heavily for existing scripts. It is from the widely available whois.py script and I have only slightly modified it as follows (see below). It was running fine on my old system (running ubuntu), but now the socket.error is being raised. I'm completely lost on this, and would really appreciate any help. Thanks! def is_available(domainname, whoisserver="whois.verisign-grs.com", cache=0): if whoisserver is None: whoisserver = "whois.networksolutions.com" s = None while s == None: try: s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.setblocking(0) try: s.connect((whoisserver, 43)) except socket.error, (ecode, reason): if ecode in (115, 150): pass else: raise socket.error, (ecode, reason) ret = select.select([s], [s], [], 30) if len(ret[1])== 0 and len(ret[0]) == 0: s.close() raise TimedOut, "on connect " s.setblocking(1) except socket.error, (ecode, reason): print ecode, reason time.sleep(1) s = None s.send("%s \n\n" % domainname) page = "" while 1: data = s.recv(8196) if not data: break page = page + data s.close()

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