Search Results

Search found 21828 results on 874 pages for 'program x'.

Page 303/874 | < Previous Page | 299 300 301 302 303 304 305 306 307 308 309 310  | Next Page >

• Need Help with wxPython & pyGame

  - by Xavier

  Hi Guys, I'm actually in need of your help and advice here on my assignment that I am working on. First of all, I was task to do a program that runs langton's ant simulation. For that, I've managed to get the source code (from snippets.dzone.com/posts/show/5143) and edited it accordingly to my requirements. This was done and ran in pygame module extension. In addition, my task requires a GUI to interface for users to run and navigate through the screens effectively with the langton's ant program running. I used wxPython with the help of an IDE called BOA constructor to create the frames, buttons, textboxes, etc. Basically, all the stuff needed in the interfaces. However, I've ran into some problems listed below: Found problem integrating pyGame with wxPython. On this note, I've research the internet for answers and tutorials where I found out from website: wiki.wxpython.org/IntegratingPyGame & aspn.activestate.com/ASPN/Mail/Message/wxpython-users/3178042. I understand from the sites that integrating pyGame with wxPython will be a difficult task where it has caused common problems like the inability to placing other controls into the frames as the pyGame application will cover the entire panel. I really hope that you can clarify my doubts on this and advise me on the path that I should take from here. Therefore, I ask the following questions: Is it feasible to integrate pyGame with wxPython? If it is not feasible to integrate pyGame with wxPython, what other alternatives do I have to create a GUI interface integrating pyGame into it. If so how do I go about? If it is possible to go about integrating pyGame with wxPython, how do I go about doing so? Really need you guys opinion on this.

  Read the article

• undefined references

  - by Brandon

  Hello, I'm trying to compile some fortran code and I'm running into some confusing linking errors. I have some code that I compile and place into a static library: >gfortran -c -I../../inc -o bdout.o bdout.F >ar rv libgeo.a bdout.o I then try to compile against that library with some simple test code and get the following: >gfortran -o mytest -L -lgeo mytest.F /tmp/cc4uvcsj.o: In function `MAIN__': mytest.F:(.text+0xb0): undefined reference to `ncwrite1_' collect2: ld returned 1 exit status It's not in the object naming because everything looks fine: >nm -u libgeo.a bdout.o: U _gfortran_exit_i4 U _gfortran_st_write U _gfortran_st_write_done U _gfortran_transfer_character U _gfortran_transfer_integer U ncobjcl_ U ncobjwrp_ U ncopencr_ U ncopenshcr_ U ncopenwr_ U ncwrite1_ U ncwrite2_ U ncwrite3_ U ncwrite4_ U ncwritev_ I can check the original object file too: >nm -u bdout.o U _gfortran_exit_i4 U _gfortran_st_write U _gfortran_st_write_done U _gfortran_transfer_character U _gfortran_transfer_integer U ncobjcl_ U ncobjwrp_ U ncopencr_ U ncopenshcr_ U ncopenwr_ U ncwrite1_ U ncwrite2_ U ncwrite3_ U ncwrite4_ U ncwritev_ The test code simply contains a single call to a function defined in bdout.o: program hello print *,"Hello World!" call ncwrite1( istat, f, ix2, ix3, ix4, ix5, ih ) end program hello I can't figure out what the problem is. Does anyone have any suggestions? Maybe even just a way to track the problem down? Cheers.

  Read the article

• Multiple, Simultaneous Factories and Protocols in Twisted: Same Service, Different Ports

  - by RichardCroasher

  Greetings, Forum. I'm working on a program in Python that uses Twisted to manage networking. The basis of this program is a TCP service that is to listen for connections on multiple ports. However, instead of using one Twisted factory to handle a protocol object for each port, I am trying to use a separate factory for each port. The reason for this is to force a separation among the groups of clients connecting to the different ports. Unfortunately, it appears that this architecture isn't quite working: clients that connect to one port appear to be available among all the factories (e.g., the protocol class used by each factory includes a 'self.factory.clients.append (self)' statement...instead of adding a given client to just the factory for a particular port, the client is added to all factories), and whenever I shutdown service on one port the listeners on all ports also stop. I've been working with Twisted for a short while, and fear I simply don't fully understand how its factory classes are managed. My question is: is it simply not possible to have multiple, simultaneous instances of the same factory and same protocol in use across different ports (without these instances stepping on each other's toes)?

  Read the article

• What is the header of an array in .NET

  - by Thomas

  Hi all, I have a little bit seen the representation of an array in memory with Windbg and SOS plugin. Here it is the c# : class myobj{ public int[] arr; } class Program{ static void Main(string[] args){ myobj o = new myobj(); o.arr = new int[7]; o.arr[0] = 0xFFFFFF; o.arr[1] = 0xFFFFFF; o.arr[2] = 0xFFFFFF; o.arr[3] = 0xFFFFFF; o.arr[4] = 0xFFFFFF; } } I break at final of Main, and I observ : 0:000> !clrstack -l OS Thread Id: 0xc3c (0) ESP EIP 0015f0cc 0043d1cf test.Program.Main(System.String[]) LOCALS: 0x0015f0d8 = 0x018a2f58 0:000 !do 0x018a2f58 Name: test.myobj MethodTable: 0026309c EEClass: 00261380 Size: 12(0xc) bytes (C:\Users\admin\Documents\Visual Studio 2008\Projects\test\test\bin\Debug\test.exe) Fields: MT Field Offset Type VT Attr Value Name 01324530 4000001 4 System.Int32[] 0 instance 018a2f64 tab 0:000 dd 018a2f64 018a2f64 01324530 00000007 00ffffff 00ffffff 018a2f74 00ffffff 00ffffff 00ffffff 00000000 018a2f84 00000000 00000000 00000000 00000000 018a2f94 00000000 00000000 00000000 00000000 018a2fa4 00000000 00000000 00000000 00000000 018a2fb4 00000000 00000000 00000000 00000000 018a2fc4 00000000 00000000 00000000 00000000 018a2fd4 00000000 00000000 00000000 00000000 I can see that the header contains the size of the array (00000007) but my question is : what is the value 01324530 ? Thanks !

  Read the article

• How is conversion of float/double to int handled in printf?

  - by Sandip

  Consider this program int main() { float f = 11.22; double d = 44.55; int i,j; i = f; //cast float to int j = d; //cast double to int printf("i = %d, j = %d, f = %d, d = %d", i,j,f,d); //This prints the following: // i = 11, j = 44, f = -536870912, d = 1076261027 return 0; } Can someone explain why the casting from double/float to int works correctly in the first case, and does not work when done in printf? This program was compiled on gcc-4.1.2 on 32-bit linux machine. EDIT: Zach's answer seems logical, i.e. use of format specifiers to figure out what to pop off the stack. However then consider this follow up question: int main() { char c = 'd'; // sizeof c is 1, however sizeof character literal // 'd' is equal to sizeof(int) in ANSI C printf("lit = %c, lit = %d , c = %c, c = %d", 'd', 'd', c, c); //this prints: lit = d, lit = 100 , c = d, c = 100 //how does printf here pop off the right number of bytes even when //the size represented by format specifiers doesn't actually match //the size of the passed arguments(char(1 byte) & char_literal(4 bytes)) return 0; } How does this work?

  Read the article

• Unable to find reference to std library math function inside library

  - by Alex Marshall

  Hello, I've got several programs that use shared libraries. Those shared libraries in turn use various standard C libraries. ie Program A and Program B both use Shared Library S. Shared Library S uses std C math. I want to be able to statically link Shared Library S against the standard library, and then statically link Programs A and B against S so that I don't have to be dragging around the library files, because these programs are going to be running on an embedded system running BusyBox 0.61. However, when I try to statically link the programs against Shared Library S, I get an error message from GCC stating : ../lib/libgainscalecalc.a(gainscalecalc.): In function 'float2gs': [path to my C file].c:73: undefined reference to 'log' Can somebody please help me out ? The make commands I'm using are below : CFLAGS += -Wall -g -W INCFLAGS = -I$(CROSS_INCLUDE)/usr/include LIBFLAGS += -L$(CROSS_LIB)/usr/lib -lm gainscalecalc_static.o: gainscalecalc.c $(CC) $(CFLAGS) -c $< -I. $(INCFLAGS) -o $@ gainscalecalc_dynamic.o: gainscalecalc.c $(CC) $(CFLAGS) -fPIC -c $< -o $@ all: staticlib dynamiclib static_driver dynamic_driver clean: $(RM) *.o *.a *.so *~ driver core $(OBJDIR) static_driver: driver.c staticlib $(CC) $(CFLAGS) -static driver.c $(INCFLAGS) $(LIBFLAGS) -I. -L. -lgainscalecalc -o $@ dynamic_driver: driver.c dynamiclib $(CC) $(CFLAGS) driver.c -o $@ -L. -lgainscalecalc staticlib: gainscalecalc_static.o $(AR) $(ARFLAGS) libgainscalecalc.a gainscalecalc_static.o $(RANLIB) libgainscalecalc.a chmod 777 libgainscalecalc.a dynamiclib: gainscalecalc_dynamic.o $(CC) -shared -o libgainscalecalc.so gainscalecalc_dynamic.o chmod 777 libgainscalecalc.so Edit: Linking against the shared libraries compiles fine, I just haven't tested them out yet

  Read the article

• How should I start playing with 3D

  - by MarceloRamires

  I'm a developer for just about 6 months now, and since I enjoy programming I make a couple of little programs. I've started making encripters, calculators, tools, stuff to play with DropBox (hehe), stuff that play with bitmaps, drawing graphics, and even a program to update the MSN display image according to the artwork of the music you're listening yo on iTunes. Now I kind of ran off ideas of programs to deal with information, and I've had an idea: play around with 3d! so I've read a little about it and figured I'd have to have good notions on position and math on point spacial position (which I do, from my 3d modelling experience), but I don't know how to use API's for it, so I've 'simulated' simple 3d with a simple program I've made (it's just a spinning cube, please, first one to open it, comment here stating that it's safe, i've got no reason to harm anyone's pc.) One of my other hobbies is 3d modelling (completly amateur) and I'd like to mix these hobbies together! Here are some questions: 1) What would be a nice 3d development tool for a .NET programmer like me? 2) Is there a way of using 3d models made in 3DS Max ? (I intend on modelling characters) 3) What knowledges should I have in order to render it, and move it areound ? 4) Which API should I use ? NOTE: Not a dupe, I'm asking for directions specific for .NET development possibly using 3ds MAX, and there are no questions about it!

  Read the article

• BlackBerry Library problems. (jre6 + NET_RIM_BLACKBERRY)

  - by kimera84

  Hi Everyone, I'm new in blackberry environement programming, I'm developing an application for this device and there are some probs about libraries that I don't understand. I have the main project called: npoBBerry - his library is NET_RIM_BLACKBERRY (from 4.6.1 version...) it includes other two projects: Npo - his library is standard jre6 (Npo inlcudes NpoCore) NpoCore - his library is standard jre6 Compliance was set... In Java Compiler level is set to 1.4 for all. Now the problem is that I'm not able to build my project. 4 errors: Error preverifying class ch.yek.npo.model.Advertising Error preverifying class ch.yek.npo.repository.Repository$1 Error!: Error: preverifier failed: C:\Program Files\eclipse\plugins\net.rim.eide.componentpack4.6.1_4.6.1.27\components\bin\preverify.ex ... Error!: Error: preverifier failed: C:\Program Files\eclipse\plugins\net.rim.eide.componentpack4.6.1_4.6.1.27\components\bin\preverify.ex ... I know that libraries are differents but maybe I'm missing something. NpoCore represents models, interfaces Npo just take data from a repository NpoBBeryy just use this data from Services... Please help and thanks in advance... :)

  Read the article

• How to parse a custom XML-style error code response from a website

  - by user1870127

  I'm developing a program that queries and prints out open data from the local transit authority, which is returned in the form of an XML response. Normally, when there are buses scheduled to run in the next few hours (and in other typical situations), the XML response generated by the page is handled correctly by the java.net.URLConnection.getInputStream() function, and I am able to print the individual results afterwards. The problem is when the buses are NOT running, or when some other problem with my queries develops after it is sent to the transit authority's web server. When the authority developed their service, they came up with their own unique error response codes, which are also sent as XMLs. For example, one of these error messages might look like this: <Error xmlns:i="http://www.w3.org/2001/XMLSchema-instance"> <Code>3005</Code> <Message>Sorry, no stop estimates found for given values.</Message> </Error> (This code and similar is all that I receive from the transit authority in such situations.) However, it appears that URLConnection.getInputStream() and some of its siblings are unable to interpret this custom code as a "valid" response that I can handle and print out as an error message. Instead, they give me a more generic HTTP/1.1 404 Not Found error. This problem cascades into my program which then prints out a java.io.FileNotFoundException error pointing to the offending input stream. My question is therefore two-fold: 1. Is there a way to retrieve, parse, and print a custom XML-formatted error code sent by a web service using the plugins that are available in Java? 2. If the above is not possible, what other tools should I use or develop to handle such custom codes as described?

  Read the article

• Java the little console game won't repeat?

  - by Jony Kale

  Okay, what I have so far is: You enter the game, and write "spin" to the console. Program will enter the while loop. In the while loop, if entered int is -1, return to the back (Set console input back to "", and let the user select what game he would like to play). Problem: Instead of going back, and selecting "spin" again, the program exits? Why is it happening? How can I fix this? private static Scanner console = new Scanner(System.in); private static Spin spin = new Spin(); private static String inputS = ""; private static int inputI = 0; private static String[] gamesArray = new String[] {"spin", "tof"}; private static boolean spinWheel = false; private static boolean tof = false; public static void main (String[] args) { if (inputS.equals("")) { System.out.println("Welcome to the system!"); System.out.print("Please select a game: "); inputS = console.nextLine(); } while (inputS.equals("spin")) { System.out.println("Welcome to the spin game! Please write 1 to spin. and -1 to exit back"); inputI = console.nextInt(); switch (inputI) { case 1: break; case -1: inputI = 0; inputS = ""; break; } } }

  Read the article

• how do i work bool!

  - by user350217

  HI! im a beginner and im really getting frustrated with this whole concept. i dont understand how to exactly use the bool function. i know what it is but i cantfigure out how to make it work in my program. Im trying to say that if my variable "selection" is any letter beween 'A' and 'I' then it is valid and can continue on to the next function which is called calcExchangeAmt(amtExchanged, selection). if it is false i want it to ask the user if they want to repeat the program and if they agree to repeat i want it to clear the screen and restart to the main function. please help edit my work! this is my bool function: bool isSelectionValid(char selection, char yesNo, double amtExchanged) { bool validData; validData = true; if((selection >= 'a' && selection <= 'i') || (selection >= 'A' && selection <= 'I')) { validData = calcExchangeAmt (amtExchanged, selection); } else(validData == false); { cout<<"Do you wish to continue? (Y for Yes / N for No)"; cin>>yesNo; } do { main(); } while ((yesNo =='y')||(yesNo == 'Y')); { system("cls"); } return 0; } this is the warning that im gettng: warning C4800: 'double' : forcing value to bool 'true' or 'false' (performance warning)

  Read the article

• Pinyin Character entry on a touchscreen keyboard

  - by mmr

  The app I'm developing requires that it be deployed in China, which means that it needs to have Pinyin and Chinese character handling. I'm told that the way that our customers handle character entry is like so: Enter in the pinyin character, like 'zhang' As they enter the characters, a list of possible Chinese (Mandarin?) characters are presented to the user, like: The user will then select '1' to enter the family name that is roughly translated to 'zhang' How can I hook such programs (I believe one is called 'mspy.exe', from Microsoft, which I'm lead to believe comes with Microsoft versions of XP) into a WPF text box? Right now, the user can enter text either by using their keyboard or by using an on-screen keyboard, so I will probably need to capture the event of a keypress from either source and feed it to some OS event or to MSPY.exe or some similar program. Or is there some other way to enter pinyin and have it converted to Mandarin? Is there a program other than MSPY I should look at? EDIT: For those of you who think that this should 'just work', it does not. Chinese character entry will work just fine if entering text into notepad or the start-run menu or whatever, but it will not work in WPF. That's the key to this question: how do I enable WPF entry? There's the Google Pinyin and Sogou pinyin, but the websites are in Mandarin or Chinese or something similar and I don't read the language.

  Read the article

• how to do bar chart in c

  - by user292489

  i have written a program that prints out the integers in the same order as the input with 5 numbers per line. That is, the first 5 integers will be printed in the first line; the next 5 integers in the next line; and so on. and also i was trying to print out the numbers in a bar chart formatt:like 81-105 ( 1) x 56-80 ( 5) xxxxx 6-11(5) xxxxx -1-5 (3) xxx my program: cntr=0; while (fscanf(in, "%d", &a[i]) != EOF) {i++; fprintf(out, "%d-%d (%d) %s\n", A, B, k, x, cntr); fprintf(out, "%d\n", k, cntr); fprintf(out, "x", a[i]); i++; } fprintf(out, "1864-2336 (%d)%s\n", k, x); fprintf(out, "1391-1863 (%d)%s\n", k, x); fprintf(out, "918-1390 (%d)%s\n", k, x); fprintf(out, "445-917 (%d)%s\n", k, x); fprintf(out,"-28-444 (%d)%s\n", k, x); fclose(in); fclose(out); return 0; } enter code here

  Read the article

• Cygwin Cruisecontrol cannot execute commands

  I'm having what I hope to be a simple problem. However, it's had me stumped all day. I'm working with cruisecontrol in windows, being set up through Cygwin. I have some CC experience in the linux platform and much of what I'm doing is very similar. However, most any command I try to execute in the config.xml file's Schedule section is giving an error. Here's the exception: ExecBuilder - Could not execute command: /cygdrive/d/Program\ Files/Subversion/bin/svn net.sourceforge.cruisecontrol.CruiseControlException: Encountered an IO exception while attempting to execute 'net.sourceforge.cruisecontrol.builders.ExecScript@b80f1c'. CruiseControl cannot continue. at net.sourceforge.cruisecontrol.builders.ScriptRunner.runScript(ScriptRunner.java:133) Here are some examples of commands I've tried to run which give this type of error. <exec command="${CCLoc}/projects/${project.name}/IOSdllScript"/> -Runs a script that I tested outside of the cruisecontrol.bat and it runs. Includes #!/bin/sh as the first line <exec command="${CCLoc}/projects/${project.name}/EmptyFile"/> -Essentially an empty text file, proving that the problem had nothing to do with my script. <exec command="/cygdrive/d/Program\ Files/Subversion/bin/svn" args="cleanup" workingdir="${svndir}"/> -Trys svn cleanup on a directory. I double checked the pathing and spelling. One command that I tested worked and didn't give this error. That command was touch. <exec command="touch" args="ABC.txt"/> I'm not sure why only touch seems to work and nothing else does. Thank you for your help.

  Read the article

• C++: Is there any good way to read/write without specifically stating character type in function nam

  - by Mark L.

  I'm having a problem getting a program to read from a file based on a template, for example: bool parse(basic_ifstream<T> &file) { T ch; locale loc = file.getloc(); basic_string<T> buf; file.unsetf(ios_base::skipws); if (file.is_open()) { while (file >> ch) { if(isalnum(ch, loc)) { buf += ch; } else if(!buf.empty()) { addWord(buf); buf.clear(); } } if(!buf.empty()) { addWord(buf); } return true; } return false; } This will work when I instantiate this class with <char>, but has problems when I use <wchar_t> (clearly). Outside of the class, I'm using: for (iter = mp.begin(); iter != mp.end(); ++iter ) { cout << iter->first << setw(textwidth - iter->first.length() + 1); cout << " " << iter->second << endl; } To write all of the information from this data struct (it's a map<basic_string<T>, int>), and as predicted, cout explodes if iter->first isn't a char array. I've looked online and the consensus is to use wcout, but unfortunately, since this program requires that the template can be changed at compile time (<char> - <wchar_t>) I'm not sure how I could get away with simply choosing cout or wcout. That is, unless there way a way to read/write wide characters without changing lots of code. If this explanation sounds awkwardly complicated, let me know and I'll address it as best I can.

  Read the article

• If statement is ignored

  - by user2898120

  I am making a simple matchmaker as a learning project in JAVA. My program so far just asks a few questions, but I wanted to do gender specific questions, so I asked for their sex (m or f) and then attempted to add a message that only showed if sex was m. The dialog should say "well done, you are male!". Else it restarts method. Every time, no matter what I type it restarts the program. Here is my code: import javax.swing.JOptionPane; public class Main { public static void main(String[] args){ setVars(); } public static void setVars(){ String name = JOptionPane.showInputDialog(null, "What is your name?"); String sAge = JOptionPane.showInputDialog(null, "What is your age?"); String sex = JOptionPane.showInputDialog(null, "What is your sex?\n(Enter m or f)"); if (sex == "m"){ JOptionPane.showMessageDialog(null, "Well done, you are male.\nKeep Going!"); } int age = Integer.parseInt(sAge); String chars = JOptionPane.showInputDialog(null, "Name three charectaristics"); } }

  Read the article

• Binder and variadic template ends up in a segmentation fault

  - by phlipsy

  I wrote the following program #include <iostream> template<typename C, typename Res, typename... Args> class bind_class_t { private: Res (C::*f)(Args...); C *c; public: bind_class_t(Res (C::*f)(Args...), C* c) : f(f), c(c) { } Res operator() (Args... args) { return (c->*f)(args...); } }; template<typename C, typename Res, typename... Args> bind_class_t<C, Res, Args...> bind_class(Res (C::*f)(Args...), C* c) { return bind_class<C, Res, Args...>(f, c); } class test { public: int add(int x, int y) { return x + y; } }; int main() { test t; // bind_class_t<test, int, int, int> b(&test::add, &t); bind_class_t<test, int, int, int> b = bind_class(&test::add, &t); std::cout << b(1, 2) << std::endl; return 0; } compiled it with gcc 4.3.3 and got a segmentation fault. After spending some time with gdb and this program it seems to me that the addresses of the function and the class are mixed up and a call of the data address of the class isn't allowed. Moreover if I use the commented line instead everything works fine. Can anyone else reproduce this behavior and/or explain me what's going wrong here?

  Read the article

• A question on delegates and method parameters

  - by Srinivas Reddy Thatiparthy

  public class Program { delegate void Srini(string param); static void Main(string[] args) { Srini sr = new Srini(PrintHello1); sr += new Srini(PrintHello2); //case 2: sr += new Srini(delegate(string o) { Console.WriteLine(o); }); sr += new Srini(delegate(object o) { Console.WriteLine(o.ToString()); }); //case 4: sr += new Srini(delegate { Console.WriteLine(“This line is accepted,though the method signature is not Comp”); });//case 5 sr("Hello World"); Console.Read(); } static void PrintHello1(string param) { Console.WriteLine(param); } static void PrintHello2(object param) { Console.WriteLine(param); } } Compiler doesn't complain about the case 2(see the comment),well,the reason is straight forward since string inherits from object. ,along the same lines ,Why is it complaining for anonymous method types(see the comment //case 4:) that “Cannot convert anonymous method to delegate type 'DelegateTest.Program.Srini' because the parameter types do not match the delegate parameter types” where as in case of normal method it doesn't ?or am i comparing apples with oranges? Another case is why is it accepting anonymous method without parameters?

  Read the article

• Error invoking stored procedure with input parameter from ADO.Net

  - by George2

  Hello everyone, I am using VSTS 2008 + C# + .Net 3.5 + ADO.Net. Here is my code and related error message. The error message says, @Param1 is not supplied, but actually it is supplied in my code. Any ideas what is wrong? System.Data.SqlClient.SqlException: Procedure or function 'Pr_Foo' expects parameter '@Param1', which was not supplied. class Program { private static SqlCommand _command; private static SqlConnection connection; private static readonly string _storedProcedureName = "Pr_Foo"; private static readonly string connectionString = "server=.;integrated Security=sspi;initial catalog=FooDB"; public static void Prepare() { connection = new SqlConnection(connectionString); connection.Open(); _command = connection.CreateCommand(); _command.CommandText = _storedProcedureName; _command.CommandType = CommandType.StoredProcedure; } public static void Dispose() { connection.Close(); } public static void Run() { try { SqlParameter Param1 = _command.Parameters.Add("@Param1", SqlDbType.Int, 300101); Param1.Direction = ParameterDirection.Input; SqlParameter Param2 = _command.Parameters.Add("@Param2", SqlDbType.Int, 100); portal_SiteInfoID.Direction = ParameterDirection.Input; SqlParameter Param3 = _command.Parameters.Add("@Param3", SqlDbType.Int, 200); portal_RoleInfoID.Direction = ParameterDirection.Input; _command.ExecuteScalar(); } catch (Exception e) { Console.WriteLine(e); } } static void Main(string[] args) { try { Prepare(); Thread t1 = new Thread(Program.Run); t1.Start(); t1.Join(); Dispose(); } catch (Exception ex) { Console.WriteLine(ex.Message + "\t" + ex.StackTrace); } } } Thanks in advance, George

  Read the article

• Calling a method on an unitialized object (null pointer)

  - by Florin

  What is the normal behavior in Objective-C if you call a method on an object (pointer) that is nil (maybe because someone forgot to initialize it)? Shouldn't it generate some kind of an error (segmentation fault, null pointer exception...)? If this is normal behavior, is there a way of changing this behavior (by configuring the compiler) so that the program raises some kind of error / exception at runtime? To make it more clear what I am talking about, here's an example. Having this class: @interface Person : NSObject { NSString *name; } @property (nonatomic, retain) NSString *name; - (void)sayHi; @end with this implementation: @implementation Person @synthesize name; - (void)dealloc { [name release]; [super dealloc]; } - (void)sayHi { NSLog(@"Hello"); NSLog(@"My name is %@.", name); } @end Somewhere in the program I do this: Person *person = nil; //person = [[Person alloc] init]; // let's say I comment this line person.name = @"Mike"; // shouldn't I get an error here? [person sayHi]; // and here [person release]; // and here

  Read the article

• Working with a database

  - by Susan

  I have an existing program for a bank account, the user can create an account then withdraw or deposit money to the account. As a transaction is processed, labels are being used to show the current information such as (Beginning Balance, Transaction Fee, Withdrawal Amount, and Ending Balance). Now, I need to be able to keep track of the transactions being processed in a SQL database. I know how to add a database to the project and then set it up to display all of the data from the table in a gridview. This is assuming that I manually entered data into the table; however, the table should be blank when the program starts and as I process transactions, then the data should be written to the table. How do I bind my existing fields (labels) to a datatable and send the text to the table. The book that I have is all related to just displaying the data that is already in the table and I have been through a couple of tutorial online and they seem to be about the same subject. I haven't found anything on how to do what I am looking for. Can someone help me out here. I don't mind references to other websites that might have the answer. Thanks, Susan

  Read the article

• What is the Difference between GC.GetTotalMemory(false) and GC.GetTotalMemory(true)

  - by somaraj

  Hi, Could some one tell me the difference between GC.GetTotalMemory(false) and GC.GetTotalMemory(true); I have a small program and when i compared the results the first loop gives an put put < loop count 0 Diff = 32 for GC.GetTotalMemory(true); and < loop count 0 Diff = 0 for GC.GetTotalMemory(false); but shouldnt it be the otherway ? Smilarly rest of the loops prints some numbers ,which are different for both case. what does this number indicate .why is it changing as the loop increase. struct Address { public string Streat; } class Details { public string Name ; public Address address = new Address(); } class emp :IDisposable { public Details objb = new Details(); bool disposed = false; #region IDisposable Members public void Dispose() { Disposing(true); } void Disposing(bool disposing) { if (!disposed) disposed = disposing; objb = null; GC.SuppressFinalize(this); } #endregion } class Program { static void Main(string[] args) { long size1 = GC.GetTotalMemory(false); emp empobj = null; for (int i = 0; i < 200;i++ ) { // using (empobj = new emp()) //------- (1) { empobj = new emp(); //------- (2) empobj.objb.Name = "ssssssssssssssssss"; empobj.objb.address.Streat = "asdfasdfasdfasdf"; } long size2 = GC.GetTotalMemory(false); Console.WriteLine( "loop count " +i + " Diff = " +(size2-size1)); } } } }

  Read the article

• How do you read a file line by line in your language of choice?

  - by Jon Ericson

  I got inspired to try out Haskell again based on a recent answer. My big block is that reading a file line by line (a task made simple in languages such as Perl) seems complicated in a functional language. How do you read a file line by line in your favorite language? So that we are comparing apples to other types of apples, please write a program that numbers the lines of the input file. So if your input is: Line the first. Next line. End of communication. The output would look like: 1 Line the first. 2 Next line. 3 End of communication. I will post my Haskell program as an example. Ken commented that this question does not specify how errors should be handled. I'm not overly concerned about it because: Most answers did the obvious thing and read from stdin and wrote to stdout. The nice thing is that it puts the onus on the user to redirect those streams the way they want. So if stdin is redirected from a non-existent file, the shell will take care of reporting the error, for instance. The question is more aimed at how a language does IO than how it handles exceptions. But if necessary error handling is missing in an answer, feel free to either edit the code to fix it or make a note in the comments.

  Read the article

• How do I create a good evaluation function for a new board game?

  - by A. Rex

  I write programs to play board game variants sometimes. The basic strategy is standard alpha-beta pruning or similar searches, sometimes augmented by the usual approaches to endgames or openings. I've mostly played around with chess variants, so when it comes time to pick my evaluation function, I use a basic chess evaluation function. However, now I am writing a program to play a completely new board game. How do I choose a good or even decent evaluation function? The main challenges are that the same pieces are always on the board, so a usual material function won't change based on position, and the game has been played less than a thousand times or so, so humans don't necessarily play it enough well yet to give insight. (PS. I considered a MoGo approach, but random games aren't likely to terminate.) Any ideas? Game details: The game is played on a 10-by-10 board with a fixed six pieces per side. The pieces have certain movement rules, and interact in certain ways, but no piece is ever captured. The goal of the game is to have enough of your pieces in certain special squares on the board. The goal of the computer program is to provide a player which is competitive with or better than current human players.

  Read the article

• RFC: Whitespace's Assembly Mnemonics

  - by Noctis Skytower

  Request For Comment regarding Whitespace's Assembly Mnemonics What follows in a first generation attempt at creating mnemonics for a whitespace assembly language. STACK ===== push number copy copy number swap away away number MATH ==== add sub mul div mod HEAP ==== set get FLOW ==== part label call label goto label zero label less label back exit I/O === ochr oint ichr iint In the interest of making improvements to this small and simple instruction set, this is a second attempt. hold N Push the number onto the stack copy Duplicate the top item on the stack copy N Copy the nth item on the stack (given by the argument) onto the top of the stack swap Swap the top two items on the stack drop Discard the top item on the stack drop N Slide n items off the stack, keeping the top item add Addition sub Subtraction mul Multiplication div Integer Division mod Modulo save Store load Retrieve L: Mark a location in the program call L Call a subroutine goto L Jump unconditionally to a label if=0 L Jump to a label if the top of the stack is zero if<0 L Jump to a label if the top of the stack is negative return End a subroutine and transfer control back to the caller exit End the program print chr Output the character at the top of the stack print int Output the number at the top of the stack input chr Read a character and place it in the location given by the top of the stack input int Read a number and place it in the location given by the top of the stack What is the general consensus on the following revised list for Whitespace's assembly instructions? They definitely come from thinking outside of the box and trying to come up with a better mnemonic set than last time. When the previous python interpreter was written, it was completed over two contiguous, rushed evenings. This rewrite deserves significantly more time now that it is the summer. Of course, the next version of Whitespace (0.4) may have its instructions revised even more, but this is just a redesign of what originally was done in a few hours. Hopefully, the instructions make more sense to those new to programming jargon.

  Read the article

< Previous Page | 299 300 301 302 303 304 305 306 307 308 309 310  | Next Page >