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  • Am I using the getch() function from the ncurses library incorrectly?

    - by user1692446
    I am writing a Pacman game in c++ using the ncurses library, but I am not able to move the Pacman properly. I have used getch() to move it it up, down, left and right, but it only moves right and does not move anywhere else when I press any other key. This is a code snippet for moving up. I have written similar code with some conditions altered accordingly for moving left, right and down. int ch = getch(); if (ch == KEY_RIGHT) { int i,row,column; //getting position of cursor by getyx function for (i=column; i<=last_column; i+=2) { //time interval of 1 sec mvprintw(row,b,"<"); //print < in given (b,row) coordinates //time interval of 1 sec mvprintw(row,(b+1),"O"); //print "O" next to "<" int h = getch(); //to give the option for pressing another key if (h != KEY_RIGHT) //break current loop if another key is pressed { break; } } } if (condition) { //code to move left } Am I using getch() wrong, or is there something else I have to do?

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  • Switch front-end's of a website after X amount of hits

    - by Derek Adair
    Sorry about the title - not sure what to call this one. A client of mine would like to redirect users to different front-ends of his eCommerce site based on a hit-counter (possibly a timer?). important: -The content is moderately different in the two sites, enough to consider them two different websites. Knowing this client he will likely add more drastic content changes and other front-ends. So for this question consider the content to be -This site has a rather large back-end. With affiliate networking, multiple payment gateways, order-tracking, and several other features in the works. It is essential that these two front-ends have identical back-end functionality I know that if it was just a simple CSS swap this would be as simple as an if statement that ran off some kind of counter stored in a DB... but the different HTML markup is throwing me for a loop. Q: How can I serve two different front-ends (HTML/CSS) based on a hit counter? Also, I don't have any clue what to tag this one as...

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  • My python program always brings down my internet connection after several hours running, how do I debug and fix this problem?

    - by Shane
    I'm writing a python script checking/monitoring several server/websites status(response time and similar stuff), it's a GUI program and I use separate thread to check different server/website, and the basic structure of each thread is using an infinite while loop to request that site every random time period(15 to 30 seconds), once there's changes in website/server each thread will start a new thread to do a thorough check(requesting more pages and similar stuff). The problem is, my internet connection always got blocked/jammed/messed up after several hours running of this script, the situation is, from my script side I got urlopen error timed out each time it's requesting a page, and from my FireFox browser side I cannot open any site. But the weird thing is, the moment I close my script my Internet connection got back on immediately which means now I can surf any site through my browser, so it must be the script causing all the problem. I've checked the program carefully and even use del to delete any connection once it's used, still get the same problem. I only use urllib2, urllib, mechanize to do network requests. Anybody knows why such thing happens? How do I debug this problem? Is there a tool or something to check my network status once such situation occurs? It's really bugging me for a while... By the way I'm behind a VPN, does it have something to do with this problem? Although I don't think so because my network always get back on once the script closed, and the VPN connection never drops(as it appears) during the whole process.

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  • Programmatically parse and edit C++ Source Files

    - by Kryten
    Hi, I want to able programmatically parse and edit C++ source files. I need to be able to change/add code in certain sections of code (i.e. in functions, class blocks, etc). I would also (preferably) be able to get comments as well. Part of what I want to do can be explained by the following piece of code: CPlusPlusSourceParser cp = new CPlusPlusSourceParser(“x.cpp”); // Create C++ Source Parser Object CPlusPlusSourceFunction[] funcs = cp.getFunctions(); // Get all the functions for (int i = 0; i &lt funcs.length; i++) { // Loop through all functions funcs[i].append(/* … code I want to append …*/); // Append some code to function } cp.save(); // Save new source cp.close(); // Close file How can I do that? I’d like to be able to do this preferably in Java, C++, Perl, Python or C#. However, I am open to other language API’s.

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  • assigning selected="selected" to dynamic option list

    - by leemjac
    In an "edit article" page i have a select list which displays author first and last name, as well as authorId as the value. As well as the article context and headline and so on (fetched with a different method) - though this method also holds the authorId of the specific article. I need to have the Author of the Article selected in the option list, instead of it defaulting to the first option in the select list. what i have: echo''; //loop through author names in option list $authors_name foreach($authors_name as $nameRow){ echo'<option class="authorId" value = "' . $nameRow['AuthorID'] . '">'. $nameRow['FirstName'].' '.$nameRow['LastName'] .''; } echo'</select>'; and the jquery: var currID = ('#selectAuthor').val(); if(('.authorId').val() == currID){ $('.authorId').addClass('new_class') $('.new_class').prop('selected',true); } OR var currID = ('#selectAuthor').val(); if($("select option[value=currID]").attr('selected','selected')); Any help would be greatly appreciated, I hope what I am trying to do is clear. Thanks in advance I have simplified it with just regular input and checked it in jsfiddle.net here is the HTML '; <option value = "2">Name val 2</option> <option value = "5">Name val 5</option> <option value = "1">Name val 1</option> and here is the jquery var currID = $('#selectAuthor').val(); if($("select option[value='+currID+']").prop('selected',true));? and even then it doesn't apply selected="selected" to option with value="1"

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  • How to print contents from a session variable by looping in a foreach statement

    - by itsover9000
    im trying to write a code where can print and loop through the contents of my session variable by using a foreach statement here is my code <form class="form form-inline" method = "post" action="reportmaker.php"> <select name="rfield"> <option value="">--Select Field--</option> <?php $sc2=mysql_query("SELECT * from searchcolumn s left join report_fields r on s.scol_id=r.field_id where s.category != 'wh'"); foreach($sc2 as $sc){ ?> <option value="<?php echo $sc[advsearch_col]; ?>"><?php echo $sc[advsearch_name]; ?></option> <?php } ?> </select> <button type="submit" value = "submit" id="add" name="add" class="btn pull-right">Add More</button> </form> <?php if(isset($_POST['add'])) { $_SESSION['temp'][]=$_POST['rfield']; } if($_SESSION[temp][]!=""){ foreach($_SESSION[temp][] as $temp) { echo $temp; } } ?> the error that appears with this code is Fatal error: Cannot use [] for reading the line where the error is is this if($_SESSION[temp][]!=""){ i need to print the contents of the session array and this is the only way i know how is there a way to fix this? thanks =========EDIT thanks for the answers guys i finally got it

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  • Socket select() Handling Abrupt Disconnections

    - by Genesis
    I am currently trying to fix a bug in a proxy server I have written relating to the socket select() call. I am using the Poco C++ libraries (using SocketReactor) and the issue is actually in the Poco code which may be a bug but I have yet to receive any confirmation of this from them. What is happening is whenever a connection abruptly terminates the socket select() call is returning immediately which is what I believe it is meant to do? Anyway, it returns all of the disconnected sockets within the readable set of file descriptors but the problem is that an exception "Socket is not connected" is thrown when Poco tries to fire the onReadable event handler which is where I would be putting the code to deal with this. Given that the exception is silently caught and the onReadable event is never fired, the select() call keeps returning immediately resulting in an infinite loop in the SocketReactor. I was considering modifying the Poco code so that rather than catching the exception silently it fires a new event called onDisconnected or something like that so that a cleanup can be performed. My question is, are there any elegant ways of determining whether a socket has closed abnormally using select() calls? I was thinking of using the exception message to determine when this has occured but this seems dirty to me.

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  • Callers block until getFoo() has a value ready?

    - by Sean Owen
    I have a Java Thread which exposes a property which other threads want to access: class MyThread extends Thread { private Foo foo; ... Foo getFoo() { return foo; } ... public void run() { ... foo = makeTheFoo(); ... } } The problem is that it takes some short time from the time this runs until foo is available. Callers may call getFoo() before this and get a null. I'd rather they simply block, wait, and get the value once initialization has occurred. (foo is never changed afterwards.) It will be a matter of milliseconds until it's ready, so I'm comfortable with this approach. Now, I can make this happen with wait() and notifyAll() and there's a 95% chance I'll do it right. But I'm wondering how you all would do it; is there a primitive in java.util.concurrent that would do this, that I've missed? Or, how would you structure it? Yes, make foo volatile. Yes, synchronize on an internal lock Object and put the check in a while loop until it's not null. Am I missing anything?

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  • Function calculating the probability of a letter in an sentence

    - by Mike
    I have a function that is supposed to calculate the number of times a letter occurs in a sentence, and based on that, calculate the probability of it occurring in the sentence. To accomplish this, I have a sentence: The Washington Metropolitan Area is the most educated and affluent metropolitan area in the United States. An array of structures, containing the letter, the number of times it occurs, and the probability of it occurring, with one structure for each letter character and an additional structure for punctuation and spaces: struct letters { char letter; int occur; double prob; }box[53]; This is the function itself: void probability(letters box[53], int sum { cout<<sum<<endl<<endl; for(int c8=0;c8<26;c8++) { box[c8].prob = (box[c8].occur/sum); cout<<box[c8].letter<<endl; cout<<box[c8].occur<<endl; cout<<box[c8].prob<<endl<<endl; } } It correctly identifies that there are 90 letters in the sentence in the first line, prints out the uppercase letter as per the structure in the second line of the for loop, and prints out the number of times it occurs. It continually prints 0 for the probability. What am I doing wrong?

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  • How do I convert a simple ruby flashcard program into a ROR app?

    - by Mark Wilbur
    What I'm trying to do is make a basic flashcard app on rails. At this point, all I'm looking for is the functionality to iterate through a list of flashcards, quiz the user and let the user know if they were right or not. In ruby, it didn't take me long to write: class Card attr_accessor :answer, :question def initialize(answer = "", question="") @answer = answer @question = question end def quiz puts "What does #@question mean?" answer = gets.chomp if answer == @answer puts "Right" return true else puts "Wrong" return answer end end end class Cardlist attr_accessor :Cards def initialize(Cards = []) @Cards = Cards end def quiz Cards.each do |w| w.quiz end end end The problem I'm having with rails is figuring out where to put the logic to loop through all the cards in the list. I've made models specifying that Card belongs_to cardlist and that Cardlist has_many cards. I know application logic should go in the controller, but if I were to make a "quiz" action for my Cardlist controller, how would I make it iterate through all the cards? After each "quiz" page generated, I'd need to get an answer back from the user, respond (maybe flash) whether it was right or not and then continue onto the next question. Would any of that logic have to go into the view in order to make sure it's sending back the user inputted answers to the controller?

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  • How to get an array to check in the in_array function? See description Below...

    - by Parth
    I am fetching the data using mysql_fetch_array like : while($row = mysql_fetch_array($select)) { $tables[] =$row; } Now i need this $tables array as one dimensional array only, so that i can use it in if(in_array($val['table_name'],$tables)) { //Some Code } to check for whether the $val['table_name'] is in the $tables or not.. As for now I am getting $tables array as Array ( [0] => Array ( [TABLE_NAME] => jos_audittrail ) [1] => Array ( [TABLE_NAME] => jos_banner ) [2] => Array ( [TABLE_NAME] => jos_bannerclient ) .. .. .. .. } But I need the $tables is form of.. Array ( [0] => jos_audittrail [TABLE_NAME] => jos_audittrail [1] => jos_banner [TABLE_NAME] => jos_banner [2] => jos_bannerclient [TABLE_NAME] => jos_bannerclient .. .. .. } How can i get the above array after applying "while loop" to "$row"?

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  • Mapping individual buttons on ASP.NET MVC View to controller actions

    - by skb
    I have an application where I need the user to be able to update or delete rows of data from the database. The rows are displayed to the user using a foreach loop in the .aspx file of my view. Each row will have two text fields (txtName, txtDesc), an update button, and a delete button. What I'm not sure of, is how do I have the update button send the message to the controller for which row to update? I can see a couple way of doing this: Put each row within it's own form tag, then when the update button is clicked, it will submit the values for that row only (there will also be a hidden field with the rowId) and the controller class would take all the post values as parameters to the Update method on the controller. Somehow, have the button be scripted in a way to send back only the values for that row with a POST to the controller. Is there a way of doing this? One thing I am concerned about is if each row has different names for it's controls assigned by ASP.NET (txtName1, txtDesc1, txtName2, txtDesc2), then how will their values get mapped to the correct parameters of the Controller method?

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  • Memory Leakage using datatables

    - by Vix
    Hi, I have situation in which i'm compelled to retrieve 30,000 records each to 2 datatables.I need to do some manipulations and insert into records into the SQL server in Manipulate(dt1,dt2) function.I have to do this in 15 times as you can see in the for loop.Now I want to know what would be the effective way in terms of memory usage.I've used the first approach.Please suggest me the best approach. (1) for (int i = 0; i < 15; i++) { DataTable dt1 = GetInfo(i); DataTable dt2 = GetData(i); Manipulate(dt1,dt2); } (OR) (2) DataTable dt1 = new DataTable(); DataTable dt2 = new DataTable(); for (int i = 0; i < 15; i++) { dt1=null; dt2=null; dt1 = GetInfo(); dt2 = GetData(); Manipulate(dt1, dt2); } Thanks, Vix.

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  • c# Convert LINQ var result to actual type

    - by DrBob
    In c#, Given the following code: public class Person { public int PersonID { get; set; } public int Age { get; set; } public string Name { get; set; } } and List<Person> people = new List<Person>(); for (int i = 0; i != 15; i++) { Person p = new Person(); p.PersonID = i; p.Age = i * 12; p.Name = "Name " + i; people.Add(p); } var sortedPeople = from qPeople in people where qPeople.Age > 0 && qPeople.Age < 25 || qPeople.Age > 100 orderby qPeople.Age descending select qPeople; Can I load the results of sortedPeople back into a List<Person without a loop? Thanks.

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  • C release dynamically allocated memory

    - by user1152463
    I have defined function, which returns multidimensional array. allocation for rows arr = (char **)malloc(size); allocation for columns (in loop) arr[i] = (char *)malloc(v); and returning type is char** Everything works fine, except freeing the memory. If I call free(arr[i]) and/or free(arr) on array returned by function, it crashes. Thanks for help EDIT:: allocating fuction pole = malloc(zaznamov); char ulica[52], t[52], datum[10]; float dan; int i = 0, v; *max = 0; while (!is_eof(f)) { get_record(t, ulica, &dan, datum, f); v = strlen(ulica) - 1; pole[i] = malloc(v); strcpy(pole[i], ulica); pole[i][v] = '\0'; if (v > *max) { *max = v; } i++; } return pole;` part of main where i am calling function pole = function(); releasing memory int i; for (i = 0; i < zaznamov; i++) { free(pole[i]); pole[i] = NULL; } free(pole); pole = NULL;

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  • How to avoid resetting the java Scanner position

    - by Derek
    I have some code that looks more or less like this: while(scanner.hasNext()) { if(scanner.findInLine("Test") !=null) { //do some things }else{ scanner.nextLine(); } } I am using this to parse an ~10MB text file. The problem is, if I put a breakpoint on the while() and the scanner.nextLine(), I can see that sometimes the scanners position (in the debug window) goes back to zero. I think this is causing me some kind of loop blow up, because the regext in findInLine() starts at zero, looks through some amount of text, advancing the position, and then it randomly gets set back to zero, so it has to re-parse all that text again. Any ideas what can be causing that? Am I even doing this the right way? Thanks Some additional info: The Scanner is instantiated from an InputStream. After diubg sine debugging, it appears that there is a HearCharBuffer that Scanner uses and it only allows 1024 characters at a time, and then resets. Is there a way to avoid this, or do things differently? That seems like a small amount of characters to be able to scan. Derek

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  • Two "Calendar" entries listed on iPad - can't write to calendar using EventKit

    - by Neal
    My iOS app integrates with the device's calendar. On my iPad when I view the calendar app and tap the Calendars button on the top left to choose which calendars to show I see one entry named "Calendar". In my app when I loop through available calendars per the code below "Calendar" is listed twice. One is CalDAV for the type, the other is Local. I'm unable to create calendar entries in one of them, I believe the "Local" one, not sure why. Why do I see "Calendar" listed twice when I do NOT see it listed twice in the iCal app? public static List<string> Calendars { get { var calendars = new List<string>(); var ekCalendars = EventStore.Calendars; if (ekCalendars != null && ekCalendars.Length > 0) { foreach (EKCalendar cal in ekCalendars) { if (cal.AllowsContentModifications) calendars.Add(cal.Title); } calendars.Sort(); } return calendars; } }

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  • Callbacks on GUI Thread

    - by miguel
    We have an external data provider which, in its construtor, takes a callback thread for returning data upon. There are some issues in the system which I am suspicious are related to threading, however, in theory they cannot be, due to the fact that the callbacks should all be returned on the same thread. My question is, does code like this require thread synchronisation? class Foo { ExternalDataProvider _provider; public Foo() { // This is the c'tor for the xternal data provider, taking a callback loop as param _provider = new ExternalDataProvider(UILoop); _provider.DataArrived += ExternalProviderCallbackMethod; } public ExternalProviderCallbackMethod() { var itemArray[] = new String[4] { "item1", "item2", "item3", "item4" }; for (int i = 0; i < itemArray.Length; i++) { string s = itemArray[i]; switch(s) { case "item1": DoItem1Action(); break; case "item2": DoItem2Action(); break; default: DoDefaultAction(); break; } } } } The issue is that, very infrequently, DoItem2Action is executingwhen DoItem1Action should be exectuing. Is it at all possible threading is at fault here? In theory, as all callbacks are arriving on the same thread, they should be serialized, right? So there should be no need for thread sync here?

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  • C++ STL Map vs Vector speed

    - by sub
    In the interpreter for my experimental programming language I have a symbol table. Each symbol consists of a name and a value (the value can be e.g.: of type string, int, function, etc.). At first I represented the table with a vector and iterated through the symbols checking if the given symbol name fitted. Then I though using a map, in my case map<string,symbol>, would be better than iterating through the vector all the time but: It's a bit hard to explain this part but I'll try. If a variable is retrieved the first time in a program in my language, of course its position in the symbol table has to be found (using vector now). If I would iterate through the vector every time the line gets executed (think of a loop), it would be terribly slow (as it currently is, nearly as slow as microsoft's batch). So I could use a map to retrieve the variable: SymbolTable[ myVar.Name ] But think of the following: If the variable, still using vector, is found the first time, I can store its exact integer position in the vector with it. That means: The next time it is needed, my interpreter knows that it has been "cached" and doesn't search the symbol table for it but does something like SymbolTable.at( myVar.CachedPosition ). Now my (rather hard?) question: Should I use a vector for the symbol table together with caching the position of the variable in the vector? Should I rather use a map? Why? How fast is the [] operator? Should I use something completely different?

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  • Form iteration function not working properly

    - by Moses
    My function is supposed to iterate all forms in the document, and bind an onclick function to each 'calculate' element int he form. The problem is, the function that executes on any of the click events executes in the context of the the last i in the loop. Here is the JavaScript that I'm using: window.onload = function(){ calculateSavings(); } function calculateSavings(){ for (i = 0; i < document.forms.length; i++) { var e = document.forms[i]; e.calculate.onclick = function() { var hours = e.hours.value; var rate = e.rate.value; alert(hours * rate); } } } And here is the HTML it is attached to: <!doctype html> <html> <body> <form> <label for="hours">Hours: </label><input type="text" id="hours" name="hours"> <label for="rate">Rate: </label><input type="text" id="rate" name="rate"> <input type="button" name="calculate" value="Calculate"> <div id="savings"></div> </form> <form> <label for="hours">Hours: </label><input type="text" id="hours" name="hours"> <label for="rate">Rate: </label><input type="text" id="rate" name="rate"> <input type="button" name="calculate" value="Calculate"> <div id="savings"></div> </form> </body> </html> I'm sure this is a really basic question but the solution is completely eluding me at this point.

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  • Why does this log output show the same answer in each iteration?

    - by Will Hancock
    OK, I was reading an article on optimising JS for Googles V8 engine, when i saw this code example... I nearly skimmed over it, but then I saw this; |=; a[0] |= b; a = new Array(); a[0] = 0; for (var b = 0; b < 10; b++) { console.log(a, b) a[0] |= b; // Much better! 2x faster. } a[0] |= b; So I ran it, in my console, with a console.log in the loop and resulted in 15; [15] 0 [15] 1 [15] 2 [15] 3 [15] 4 [15] 5 [15] 6 [15] 7 [15] 8 [15] 9 WHAT?!?! Where the hell does it get 15 from, on every iteration?!?!?! I've been a web dev for 7 years, and this has stumped me and a fellow colleague. Can somebody talk me through this code? Cheers.

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  • What's the proper approach for writing multi-path "story" flows?

    - by Basiclife
    Hi, I wonder if you can help me. I'm writing a game (2d) which allows players to take multiple routes, some of which branch/merge - perhaps even loop. Each section of the game will decide which section is loaded next. I'm calling each section an IStoryElement - And I'm wondering how best to link these elements up in a way that is easily changed/configured and at the same time, graphable I'm going to have an engine/factory assembly which will load the appropriate StoryElement(s) based on various config options. I initially planned to give each StoryElement a NextElement() As IStoryElement property and a Completed() event. When the vent fires, the engine reads the NextElement property to find the next StoryElement. The downside to this is that if I ever wanted to graph all the routes through the game, I would be unable to - I couldn't determine all possible targets for each StoryElement. I considered a couple of other solutions but they all feel a little clunky - eg Do I need an additional layer of abstraction? ie StoryElementPlayers or similar - Each one would be responsible for stringing together multiple StoryElement perhaps a Series and a ChoicePlayer with each responsible for graphing its own StoryElement - But this will just move the problem up a layer. In short, I need some way of emulating a simple but dynamic workflow (but I'd rather not actually use WWF). Is there a pattern for something this simple? All the ones I've managed to find relate to more advanced control flow (parallel processing, etc.)

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  • Images from url to listview

    - by Andres
    I have a listview which I show video results from YouTube. Everything works fine but one thing I noticed is that the way it works seems to be a bit slow and it might be due to my code. Are there any suggestions on how I can make this better? Maybe loading the images directly from the url instead of using a webclient? I am adding the listview items in a loop from video feeds returned from a query using the YouTube API. The piece of code which I think is slowing it down is this: Feed<Video> videoFeed = request.Get<Video>(query); int i = 0; foreach (Video entry in videoFeed.Entries) { string[] info = printVideoEntry(entry).Split(','); WebClient wc = new WebClient(); wc.DownloadFile(@"http://img.youtube.com/vi/" + info[0].ToString() + "/hqdefault.jpg", info[0].ToString() + ".jpg"); string[] row1 = { "", info[0].ToString(), info[1].ToString() }; ListViewItem item = new ListViewItem(row1, i); YoutubeList.Items.Add(item); imageListSmall.Images.Add(Bitmap.FromFile(info[0].ToString() + @".jpg")); imageListLarge.Images.Add(Bitmap.FromFile(info[0].ToString() + @".jpg")); } public static string printVideoEntry(Video video) { return video.VideoId + "," + video.Title; } As you can see I use a Webclient which downloads the images so then I can use them as image in my listview. It works but what I'm concerned about is speed..any suggestions? maybe a different control all together?

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  • How to insert several thousand columns into sqlite3?

    - by user291071
    Similar to my last question, but I ran into problem lets say I have a simple dictionary like below but its Big, when I try inserting a big dictionary using the methods below I get operational error for the c.execute(schema) for too many columns so what should be my alternate method to populate an sql databases columns? Using the alter table command and add each one individually? import sqlite3 con = sqlite3.connect('simple.db') c = con.cursor() dic = { 'x1':{'y1':1.0,'y2':0.0}, 'x2':{'y1':0.0,'y2':2.0,'joe bla':1.5}, 'x3':{'y2':2.0,'y3 45 etc':1.5} } # 1. Find the unique column names. columns = set() for _, cols in dic.items(): for key, _ in cols.items(): columns.add(key) # 2. Create the schema. col_defs = [ # Start with the column for our key name '"row_name" VARCHAR(2) NOT NULL PRIMARY KEY' ] for column in columns: col_defs.append('"%s" REAL NULL' % column) schema = "CREATE TABLE simple (%s);" % ",".join(col_defs) c.execute(schema) # 3. Loop through each row for row_name, cols in dic.items(): # Compile the data we have for this row. col_names = cols.keys() col_values = [str(val) for val in cols.values()] # Insert it. sql = 'INSERT INTO simple ("row_name", "%s") VALUES ("%s", "%s");' % ( '","'.join(col_names), row_name, '","'.join(col_values) )

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  • what use does the javascript for each method have (that map can't do)?

    - by JohnMerlino
    Hey all, The only difference I see in map and foreach is that map is returning an array and foreach is not. However, I don't even understand the last line of the foreach method "func.call(scope, this[i], i, this);". For example, isn't "this" and "scope" referring to same object and isn't this[i] and i referring to the current value in the loop? I noticed on another post someone said "Use forEach when you want to do something on the basis of each element of the list. You might be adding things to the page, for example. Essentially, it's great for when you want "side effects". I don't know what is meant by side effects. Array.prototype.map = function(fnc) { var a = new Array(this.length); for (var i = 0; i < this.length; i++) { a[i] = fnc(this[i]); } return a; } Array.prototype.forEach = function(func, scope) { scope = scope || this; for (var i = 0, l = this.length; i < l; i++) func.call(scope, this[i], i, this); } Finally, are there any real uses for these methods in javascript (since we aren't updating a database) other than to manipulate numbers like this: alert([1,2,3,4].map(function(x){ return x + 1})); //this is the only example I ever see of map in javascript. Thanks for any reply.

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