Search Results

Search found 12653 results on 507 pages for 'c programming'.

Page 468/507 | < Previous Page | 464 465 466 467 468 469 470 471 472 473 474 475  | Next Page >

• C/C++ Bit Array or Bit Vector

  - by MovieYoda

  Hi, I am learning C/C++ programming & have encountered the usage of 'Bit arrays' or 'Bit Vectors'. Am not able to understand their purpose? here are my doubts - Are they used as boolean flags? Can one use int arrays instead? (more memory of course, but..) What's this concept of Bit-Masking? If bit-masking is simple bit operations to get an appropriate flag, how do one program for them? is it not difficult to do this operation in head to see what the flag would be, as apposed to decimal numbers? I am looking for applications, so that I can understand better. for Eg - Q. You are given a file containing integers in the range (1 to 1 million). There are some duplicates and hence some numbers are missing. Find the fastest way of finding missing numbers? For the above question, I have read solutions telling me to use bit arrays. How would one store each integer in a bit?

  Read the article

• Attribute value nil

  - by mridula

  Can someone tell me why is this happening? I have created a social networking website using Ruby on Rails. This is my first time programming with RoR. I have a model named "Friendship" which contains an attribute "blocked" to indicate whether the user has blocked another user. When I run the following in IRB - friendship = u.friendships.where(:friend_id => 22).first IRB gives me - Friendship Load (0.6ms) SELECT `friendships`.* FROM `friendships` WHERE `friendships`.`user_id` = 17 AND `friendships`.`friend_id` = 22 LIMIT 1 => #<Friendship id: 33, user_id: 17, friend_id: 22, created_at: "2012-04-07 10:29:49", updated_at: "2012-04-07 10:29:49", blocked: 1> As u can see, the "blocked" attribute has value '1'. But when I run the following 1.9.2-p290 :030 > friendship.blocked => nil - it says, the value of blocked is 'nil' and not '1'. Why is this happening? This could be a very silly mistake but I am new to RoR, so kindly help me! I initially didn't include the accessor method for 'blocked'.. I tried that, and still its giving the same result.. Following is the Friendship model.. class Friendship < ActiveRecord::Base belongs_to :friend, :class_name => "User" validates_uniqueness_of :friend_id , :scope => :user_id attr_accessor :blocked attr_accessible :blocked end Here is the schema of the table: 1.9.2-p290 :009 > friendship.class => Friendship(id: integer, user_id: integer, friend_id: integer, created_at: datetime, updated_at: datetime, blocked: integer)

  Read the article

• How: Start an Activity inside a Thread and use finish() to get back.

  - by Kirk Becker

  Hello, I am programming a game on android. I'm using a Thread while calling a Surface View class to update and draw my game. Inside the update I wanted to start an activity based on if the game has just started and this would launch my MENUS. My Thread for the most part.. while (myThreadRun) { Canvas c = null; try { gameTime = System.currentTimeMillis(); c = myThreadSurfaceHolder.lockCanvas(null); synchronized (myThreadSurfaceHolder) { // Update Game. myThreadSurfaceView.onUpdate(); // Draw Game. myThreadSurfaceView.onDraw(c); You can see there where I am updating the game... here is onUpdate(); protected void onUpdate() { // Test if menu needs to be displayed. while (thread.getMenu()) { // Test if menu activity has been started. if (thread.getMenuRunning() == false) { Intent menuIntent = new Intent(this.getContext(), MyMenu.class); ((Activity) cxt).startActivityForResult(menuIntent, 1); thread.setMenuRunning(true); } } I am using a while loop because if I didn't use it the thread just keeps going. Basically I just don't know how to implement my menus using a thread as a game loop. Everywhere I look it seems like that's best practice. In my menu activity I just display the menu layout and a few buttons and when the person wants to start the game it uses finish() to go back to my thread where they play the game. I am very new to this so any insight will be helpful, Thanks

  Read the article

• User input being limited to the alphabet in python

  - by Danger Cat

  I am SUPER new to programming and have my first assignment coming up in python. I am writing a hangman type game, where users are required to guess the word inputted from the other user. I have written most of the code, but the only problem I am having is when users have to input the word, making sure it is only limited to the alphabet. The code I have so far is : word = str.lower(raw_input("Type in your secret word! Shhhh... ")) answer = True while answer == True: for i in range(len(word)): if word[i] not in ("abcdefghijklmnopqrstuvwxyz"): word = raw_input("Sorry, words only contain letters. Please enter a word ") break else: answer = False This works while I input a few tries, but eventually will either exit the loop or displays an error. Is there any easier way to use this? We've really only covered topics up to loops in class, and break and continue are also very new to me. Thank you! (Pardon if the code is sloppy, but as I said I am very new to this....)

  Read the article

• Swing Menu dimensions

  - by ikurtz

  Greetings. I am trying to learn Java and Swing (today is my first day). I have been able to set up a menu in my test application. but the items occupy very little space (they are narrow). How do I go about extendng the amount of space it uses? I am studying Teach Yourself Java 6 in 21 Days 5th Ed, Java Swing, 2nd Edition, 2002 and Teach Yourself Programming With Java In 24 Hours, 4th Edition (2005) but none of them shed any light on this issue. EDIT: Menu code: JMenu _Game = new JMenu("Game"); JMenuItem _New = new JMenuItem("New"); JMenuItem _Exit = new JMenuItem("Exit"); JMenu _Turn = new JMenu("Turn"); JMenuItem _Red = new JMenuItem("Red"); JMenuItem _Yellow = new JMenuItem("Yellow"); _Turn.add(_Red); _Turn.add(_Yellow); _Game.add(_New); _Game.addSeparator(); _Game.add(_Turn); _Game.addSeparator(); _Game.add(_Exit); JMenu _Help = new JMenu("Help"); JMenuItem _About = new JMenuItem("About"); _Help.add(_About); JMenuBar _MenuBar = new JMenuBar(); _MenuBar.add(_Game); _MenuBar.add(_Help); setJMenuBar(_MenuBar); EDIT: Solved! JMenuItem _New = new JMenuItem("New "); just add spaces as needed! simple.

  Read the article

• question about quicksort

  - by davit-datuashvili

  i have write code of quicksort from programming pearls here is code public class Quick{ public static void quicksort(int x[], int l,int u) { if (l>=u) return ; int t=x[l]; int i=l; int j=u; do { i++; } while (i<=u && x[i]<t); do { j--; if (i>=j) break; } while ( x[j]>t); swap(x,i,j); swap(x, l,j); quicksort(x, l,j-1); quicksort(x, j+1,u); } public static void main(String[]args){ int x[]=new int[]{55,41,59,26,53,58,97,93}; quicksort(x,0,x.length-1); for (int i=0;i<x.length;i++){ System.out.println(x[i]); } } public static void swap(int x[], int i,int j){ int s=x[i]; x[i]=x[j]; x[j]=s; } } but it does not work here is output 59 41 55 26 53 97 58 93 any idea?

  Read the article

• Embedded Youtube video in a Ruby on Rails page

  - by dan

  Hi, New to programming. I am trying to embed a YouTube video from a link stored in a database named "Promoter" into a ruby-on-rails page (.erb). I've looked at the source the code turns out, but the object video player does not appear (on heroku here: http://blazing-mountain-574.heroku.com/). The code in the home.html.erb file: <h1>Pages#home</h1> <p>Find me in app/views/pages/home.html.erb</p> <object width="640" height="385"> <param name="movie" value="<%= sanitize Promoter.first.link %>"> </param><param name="allowFullScreen" value="true"></param ><param name="allowscriptaccess" value="always"></param> <embed src="<%= sanitize Promoter.first.link %>" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="640" height="385"></embed></object> Is there something real simple that I'm missing?

  Read the article

• View Controller Question

  - by user341444

  First off I'm new at programming. I'm creating an app with one navigation bar controller. The app is pretty basic except for a quiz section that is comprised of 12 xibs. As the users takes the quiz a new xib is pushed onto the stack. I want to create a button that takes the user back to the home screen if they do not want to complete the quiz. The back button takes them to the previous xib which could be 11 deep. Is it possible to dismiss the modal views and reload the rootView controller? Here's the code from my delegate @synthesize window; @synthesize navigationController; (void)applicationDidFinishLaunching:(UIApplication *)application { // Override point for customization after application launch [window addSubview:[navigationController view]]; [window makeKeyAndVisible]; } (void)dealloc { [window release]; [navigationController release]; [super dealloc]; } This is how I'm pushing new xibs onto the stack (IBAction) showTesting: (id)sender { Testing *varTesting = [[[Testing alloc] initWithNibName:@"Testing" bundle:nil] autorelease]; [[self navigationController] pushViewController:varTesting animated: YES]; } Any help would be greatly appreciated. Thanks

  Read the article

• Is the 'var' keyword bad? Or am I just old school?

  - by WaggingSiberian

  Recently I overheard junior developer ask "why do you use 'var' so much?". The mid-level developer responded "I use VAR all the time. I love it! I don't have to figure out the type." I didn't have the time or energy to get into a religious war and hey, I'm still the new guy here :-) I understand var has its place. LINQ comes to mind. But I have also always been told the use of var represents lazy programming and I should just use the correct type to begin with. If it's an int, define it as an int, not a var. When reviewing code, seeing the type makes it easier to follow. My opinion is, it's just lazy but there are exceptions. Var also reminds me of the VB/VBA variant type. It also had its place. I recall (from many years ago) its usage being less-than-desirable type and it was rather resource hungry. Am I just being stuck in my ways? Should we start using var all the time as my co-worker does?

  Read the article

• Is there an user-level accessible font table present in Linux?

  - by youngdood

  Hi again Stackoverflow! Since there is this: http://en.wikipedia.org/wiki/Code_page_437 For MSDOS, is there something similar for Linux systems? Is it possible to access that font data via userland program? I would actually just need an access to the actual bit patterns which define the font, and I would do the rendering myself. I'm fairly sure that something like this exists, but I haven't been able to find what exactly is it and how to access it. After all, e.g. text mode console font has to reside somewhere, and I really do hope it is "rawly" accessible somehow for a userland program. Before I forget, I'm programming my program in C, and have access only to the "standard" linux/posix development headers. The only thing I could came up with myself is to use the fonts in /usr/share/fonts, but having to write my own implementations to extract the data from there doesn't sound really an option; I would really want to achieve this with the least amount of bytes possible, so I feel I'm left with finding a standard way of doing this. It's not really feasible for me to store my own 8x8 ASCII-compatible font with the program either(it takes some 1024 bytes(128 chars * 8x8 bits) just to store the font, which is definitely unacceptable for the strict size limits(some < 1024 bytes for code+data) which I am working with), so being able to use the font data stored at the system itself would greatly simplify my task.

  Read the article

• android nested lists

  - by Raogrimm

  i'm new to programming android and i have found some useful things for my app, but i can't seem to find how to make a list filled with an string array display a new list that is going to be populated with a string array. i would like to have the user choose an item from the top_menu list and from there go to the desired area and have that array appear. this is what i have so far: public class HelloListActivity extends ListActivity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); String[] top_menu = getResources().getStringArray(R.array.top_menu); setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, top_menu)); ListView lv = getListView(); lv.setTextFilterEnabled(true); lv.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView<?> parent, View view, int position, long id) { ??? } }); } all my arrays are working fine, i just don't know how to repopulate a new list with the other array depending on the choice the user made. any help is greatly appreciated

  Read the article

• How do I use requestFocus in a Java JFrame GUI?

  - by JohnWong

  I am given an assignment but I am totally new to Java (I have been programming in C++ and Python for two years). So we are doing GUI and basically we extended JFrame and added a couple fields. Say we have a field named "Text 1" and "Text 2". When user presses enter with the cursor in Text 1, move the focus to Text 2. I tried to add private JTextField textfield1() { textfield1 = new JTextField(); textfield1.setPreferredSize(new Dimension(200, 20)); textfield1.addActionListener( new ActionListener() { public void actionPerformed(ActionEvent e) { textfield1text = textfield1.getText().trim(); textfield1.setText(textfield1text); System.out.println(textfield1text); textfield1.requestFocus(); } }); return textfield1; } But that doesn't work at all. I noticed that requestFocus is not recommended, and instead one should use requestFocusWindows. But I tried that too. Upon some readings it seems like I have to do keyboard action and listener? But my teacher said it only requires 1 line...

  Read the article

• C# form - checkboxes do not respond to plus/minus keys - easy workaround?

  - by Scott

  On forms created with pre dotNET VB and C++ (MFC), a checkbox control responded to the plus/minus key without custom programming. When focus was on the checbox control, pressing PLUS would check the box, no matter what the previous state (checked/unchecked), while pressing MINUS would uncheck it, no matter the previous state. C# winform checkboxes do not seem to exhibit this behavior. Said behavior was very, very handy for automation, whereby the automating program would set focus to a checkbox control and issue a PLUS or MINUS to check or uncheck it. Without this capability, that cannot be done, as the automation program (at least the one I am using) is unable to query the current state of the checkbox (so it can decide whether to issue a SPACE key to toggle the state to the desired one). I've gone over the properties of a checkbox in the Visual Studio 2008 IDE and could not find anything that would restore/enable response to PLUS/MINUS. Since I am in control of the sourcecode for the WinForms in question, I could replace all checkbox controls with a custom checkbox control, but blech, I'd like to avoid that - heck, I don't think I could even consider that given the amount of refactoring that would need to be done. So the bottom line is: does anyone know of a way to get this behavior back more easily than a coding change?

  Read the article

• What are the benefits of a classical structure over a prototyple one?

  - by Rixius

  I have only recently started programming significantly, and being completely self-taught, I unfortunately don't have the benefits of a detailed Computer science course. I've been reading a lot about JavaScript lately, and I'm trying to find the benefit in classes over the prototype nature of JavaScript. The question seems to be drawn down the middle of which one is better, and I want to see the classical side of it. When I look at the prototype example: var inst_a = { "X": 123, "Y": 321, add: function () { return this.X+this.Y; } }; document.write(inst_a.add()); And then the classical version function A(x,y){ this.X = x; this.Y = y; this.add = function(){ return this.X+this.Y; }; }; var inst_a = new A(123,321); document.write(inst_a.add()); I begun thinking about this because I'm looking at the new ecmascript revision 5 and a lot of people seem up in arms that they didn't add a Class system.

  Read the article

• Ruby on Rails or PHP... Somehow uncertain

  - by Clamm

  Hi everybody... I've been thinking about this a long time now but i wanna hear your opinion because i always received the ebst answers here. So in advance... thank you guys. Right now i have to make this decision: Shift a prototype webservice to production quality. Choose either Ruby or PHP... (Background: A friend of mine is joining the project and prefers rails) I've already played around a bit with RoR (only basic stuff) but i am really disappointed about the documentation of Rails and Ruby. In relation to PHP i find only fragments or hard to use references. At the end i am a bit scared. I dont wanna waste my time realizing that i am not capable of doing s.th in Ruby what i could with PHP. Maybe only because i am too stupid and don't find a proper explanation ;-) Did anyone experience this shift and can tell me how easy/hard it was to switch from PHP to Ruby? E.G. would you recommend programming it in PHP and using MVC as a base pattern? Thanks for your opinion!!!

  Read the article

• How to give "Share with" option while opening documents in iphone mail

  - by rishabh

  So I've been going through the "Document Interaction Programming Topics for iOS". I've been able to achieve the "Open with myapp" option through Mail, was wondering how can I change the option to "Share with myapp" depending upon the file types specified? This is what I've tried: <key>CFBundleDocumentTypes</key> <array> <dict> <key>CFBundleTypeName</key> <string>Document</string> <key>LSHandlerRank</key> <string>Alternate</string> <key>CFBundleTypeRole</key> <string>Owner</string> <key>LSItemContentTypes</key> <array> <string>public.data</string> </array> </dict> </array>

  Read the article

• Python, web log data mining for frequent patterns

  - by descent

  Hello! I need to develop a tool for web log data mining. Having many sequences of urls, requested in a particular user session (retrieved from web-application logs), I need to figure out the patterns of usage and groups (clusters) of users of the website. I am new to Data Mining, and now examining Google a lot. Found some useful info, i.e. querying Frequent Pattern Mining in Web Log Data seems to point to almost exactly similar studies. So my questions are: Are there any python-based tools that do what I need or at least smth similar? Can Orange toolkit be of any help? Can reading the book Programming Collective Intelligence be of any help? What to Google for, what to read, which relatively simple algorithms to use best? I am very limited in time (to around a week), so any help would be extremely precious. What I need is to point me into the right direction and the advice of how to accomplish the task in the shortest time. Thanks in advance!

  Read the article

• ANDROID SAX Parser issue

  - by Chris Watson

  Since I am new to java programming, I need a bit of help with this. I stuck on this one issue and can't continue until I get this to work. I am trying to make a string from that includes a preference int. I saved the data and can display the int (just sample code): SharedPreferences prefs=PreferenceManager .getDefaultSharedPreferences(this); list.setText(prefs.getString("list", "22")); now, I have a xml parser that is pulling a url correctly as a static string: public static String feedUrl = String.format("http://www.freshpointmarketing.com/iphone/objects/XML/AND.php?ID=%d", 22); Works great... now my issue...... I need to have the preference "int" become the variable in the string, thus making it not static. static SharedPreferences prefs=PreferenceManager.getDefaultSharedPreferences(this); static int myVariable = prefs.getInt("list1", 22); public static String feedUrl = String.format("http://www.freshpointmarketing.com/iphone/objects/XML/AND.php?ID=%d", myVariable); If I take out all static references, I get an error on this: private void loadFeed(ParserType type){ try{ FeedParser parser = FeedParserFactory.getParser(type); long start = System.currentTimeMillis(); messages = parser.parse(); long duration = System.currentTimeMillis() - start; Log.i("AndroidNews", "Parser duration=" + duration); String xml = writeXml(); Log.i("AndroidNews", xml); List<String> titles = new ArrayList<String>(messages.size()); for (Message msg : messages){ titles.add(msg.getTitle()); } ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.row,titles); this.setListAdapter(adapter); } catch (Throwable t){ Log.e("AndroidNews",t.getMessage(),t); } } thanks

  Read the article

• please help me to solve problem

  - by davit-datuashvili

  first of all this is not homework and nobody tag it as homewrok i did not understand this porblem can anybody explain me?this is not english problem it is just misunderstanding what problem say Consider the problem of neatly printing a paragraph on a printer. The input text is a sequence of n words of lengths l1 , l2 , . . . , ln , measured in characters. We want to print this paragraph neatly on a number of lines that hold a maximum of M characters each. Our criterion of “neatness” is as follows. If a given line contains words i through j , where i = j , and we leave exactly one space between words, the number of extra space characters at the end of the line is M - j + i -(k=i,k< j,k++) lk , which must be nonnegative so that the words fit on the line. We wish to minimize the sum, over all lines except the last, of the cubes of the numbers of extra space characters at the ends of lines. Give a dynamic-programming algorithm to print a paragraph of n words neatly on a printer. Analyze the running time and space requirements of your algorithm.

  Read the article

• First Time Working With Others?

  - by cam

  I've been at my very first programming job for about 8 months now and I've learned incredible amounts so far. Unfortunately, I'm the sole developer for a small startup company for internal applications. For the first time ever though, I'll be handing off some of my projects to someone else when I leave this job. I've documented all my projects thoroughly (at least I think so), but I still feel nervous about someone else reading my code. For example, I've always done this sort of thing. for (int i = 0; i < blah.length; i++) { //Do stuff } Should I name 'i' something descriptive? It's only a temporary variable, and will only exist within that loop, and it seems that it's pretty obvious what the loop does with 'i'. This is just one example. Another one is that I name variables differently... I don't really conform to a standard of naming besides starting all private members with an underscore. Are there any resources that could show me how to make it easier for the next developer? Are there standards for this type of thing?

  Read the article

• Vector Usage in MPI(C++)

  - by lsk1985

  I am new to MPI programming,stiil learning , i was successful till creating the Derived data-types by defining the structures . Now i want to include Vector in my structure and want to send the data across the Process. for ex: struct Structure{ //Constructor Structure(): X(nodes),mass(nodes),ac(nodes) { //code to calculate the mass and accelerations } //Destructor Structure() {} //Variables double radius; double volume; vector<double> mass; vector<double> area; //and some other variables //Methods to calculate some physical properties Now using MPI i want to sent the data in the structure across the processes. Is it possible for me to create the MPI_type_struct vectors included and send the data? I tried reading through forums, but i am not able to get the clear picture from the responses given there. Hope i would be able to get a clear idea or approach to send the data PS: i can send the data individually , but its an overhead of sending the data using may MPI_Send/Recieve if we consider the domain very large(say 10000*10000)

  Read the article

• Should I use a class in this: Reading a XML file using lxml.

  - by PulpFiction

  Hi everyone. This question is in continuation to my previous question, in which I asked about passing around an ElementTree. I need to read the XML files only and to solve this, I decided to create a global ElementTree and then parse it wherever required. My question is: Is this an acceptable practice? I heard global variables are bad. If I don't make it global, I was suggested to make a class. But do I really need to create a class? What benefits would I have from that approach. Note that I would be handling only one ElementTree instance per run, the operations are read-only. If I don't use a class, how and where do I declare that ElementTree so that it available globally? (Note that I would be importing this module) Please answer this question in the respect that I am a beginner to development, and at this stage I can't figure out whether to use a class or just go with the functional style programming approach.

  Read the article

• c Pointer to pointer, or passing list to functions

  - by user361808

  Hi, I am new to c programming. Could anyone please tell me what's wrong with the following program? typedef struct Person_s { int age; char name[40]; } Person_t; int process_list(int *countReturned, Person_t **p_list) { Person_t *rowPtr=0; //the actual program will fethc data from DB int count =1; if(!((*p_list) = (Person_t *) malloc(sizeof(Person_t)))) { return -1; } rowPtr = *p_list; rowPtr[count-1].age =19; strcpy(rowPtr[count-1].name,"Prince Dastan"); *countReturned = count; return 0; } int main(int argc, char *argv[]) { Person_t *tmpPerson=0; Person_t **p_list=0; int *count=0; int i; process_list(count,p_list); tmpPerson = *p_list; for(i=0; i< *count; i++) { printf("Name: %s , age: %d\n",tmpPerson->name,tmpPerson->age); tmpPerson++; } //free(tmpPerson); return 0; }

  Read the article

• Socket Performance C++ Or C#

  - by modernzombie

  I have to write an application that is essentially a proxy server to handle all HTTP and HTTPS requests from our server (web browsing, etc). I know very little C++ and am very comfortable writing the application features in C#. I have experimented with the proxy from Mentalis (socket proxy) which seems to work fine for small webpages but if I go to large sites like tigerdirect.ca and browse through a couple of layers it is very slow and sometimes requests don't complete and I see broken images and javascript errors. This happens with all of our vendor sites and other content heavy sites. Mentalis uses HTTP 1.0 which I know is not as efficient but should a proxy be that slow? What is an acceptable amount of performance loss from using a proxy? Would HTTP 1.1 make a noticeable difference? Would a C++ proxy be much faster than one in C#? Is the Mentalis code just not efficient? Would I be able to use a premade C++ proxy and import the DLL to C# and still get good performance or would this project call for all C++? Sorry if these are obvious questions but I have not done network programming before.

  Read the article

• Show dialog while loading new screen

  - by darkdusky

  I have a front screen with a button which opens a second screen. The second screen can take a few seconds to load so I want to display a dialog while loading. My problem is the dialog does not display while loading second screen, but it displays when I return to first page from the second page. If I comment out the "startActivity" to open second page the dialog shows fine. I'm fairly new to android programming - I guess it has something to do with threads. //code snippet from inside onCreate: NewGame.setOnClickListener(new View.OnClickListener() { public void onClick(View arg0) { //does not get displayed before 2nd page opens showDialog(DIALOG2_KEY); //shows fine if next 2 lines commented out Intent i = new Intent(screen1.this, SudukuXL.class); startActivity(i); I've dealt with the dialog showing on returning to the front screen using onPause(). I've tried using threads to seperate the dialog from the startActivity but I've had no luck. Any help would be appreciated. I used code from Android examples to create dialog. I include below for reference: protected Dialog onCreateDialog(int id) { switch (id) { case DIALOG2_KEY: { ProgressDialog dialog = new ProgressDialog(this); dialog.setMessage("Loading..."); dialog.setIndeterminate(true); dialog.setCancelable(true); return dialog; } } return null; }

  Read the article

< Previous Page | 464 465 466 467 468 469 470 471 472 473 474 475  | Next Page >