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  • jQuery AJAX chained calls + Celery in Django

    - by user1029968
    Currently clicking one of the links in my application, triggers AJAX call (GET) that - if succeeds - triggers the second one and this second one - if succeeds - calls the third one. This way user can be informed which part of process started when clicking the link is currently ongoing. So in the template file in Django project, click callback body for link mentioned looks like below: $("#the-link").click(function(item)) { // CALL 1 $.ajax({ url: {% url ajax_call_1 %}, data: { // something } }) .done(function(call1Result) { // CALL 2 $.ajax({ url: {% url ajax_call_1 %}, data: { // call1Result passed here to CALL 2 } }) .done(function(call2Result) { // CALL 3 $.ajax({ url: {%url ajax_call_3 %}, data: { // call2Result passed here to CALL 3 } }) .done(function(call3Result) { // expected result if everything went fine console.log("wow, it worked!"); console.log(call3Result); }) .fail(function(errorObject) { console.log("call3 failed"); console.log(errorObject); } }) .fail(function(errorObject)) { console.log("call2 failed"); console.log(errorObject); } }) .fail(function(errorObject) { console.log("call1 failed"); console.log(errorObject); }); }); This works fine for me. The thing is, I'd like to prevent interrupting the following calls if the user closes the browser and the calls are not finished (as it will take some time to finish all three), as there is some additional logic in Django view functions called in each GET request. For example, if user clicks the link and closes the browser during CALL 1, is it possible to somehow go on with the following CALL 2 and CALL 3? I know that normally I'd be able to use Celery Task to process the function but is it still possible here with the chained calls mentioned? Any help is much appreciated!

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  • C++ VB6 interfacing problem

    - by Roshan
    Hi, I'm tearing my hair out trying to solve this one, any insights will be much appreciated: I have a C++ exe which acquires data from some hardware in the main thread and processes it in another thread (thread 2). I use a c++ dll to supply some data processing functions which are called from thread 2. I have a requirement to make another set of data processing functions in VB6. I have thus created a VB6 dll, using the add-in vbAdvance to create a standard dll. When I call functions from within this VB6 dll from the main thread, everything works exactly as expected. When I call functions from this VB6 dll in thread 2, I get an access violation. I've traced the error to the CopyMemory command, it would seem that if this is used within the call from the main thread, it's fine but in a call from the process thread, it causes an exception. Why should this be so? As far as I understand, threads share the same address space. Here is the code from my VB dll Public Sub UserFunInterface(ByVal in1ptr As Long, ByVal out1ptr As Long, ByRef nsamples As Long) Dim myarray1() As Single Dim myarray2() As Single Dim i As Integer ReDim myarray1(0 To nsamples - 1) As Single ReDim myarray2(0 To nsamples - 1) As Single With tsa1din(0) ' defined as safearray1d in a global definitions module .cDims = 1 .cbElements = 4 .cElements = nsamples .pvData = in1ptr End With With tsa1dout .cDims = 1 .cbElements = 4 .cElements = nsamples .pvData = out1ptr End With CopyMemory ByVal VarPtrArray(myarray1), VarPtr(tsa1din(0)), 4 CopyMemory ByVal VarPtrArray(myarray2), VarPtr(tsa1dout), 4 For i = 0 To nsamples - 1 myarray2(i) = myarray1(i) * 2 Next i ZeroMemory ByVal VarPtrArray(myarray1), 4 ZeroMemory ByVal VarPtrArray(myarray2), 4 End Sub

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  • Web development scheme for staging and production servers using Git Push

    - by ServAce85
    I am using git to manage a dynamic website (PHP + MySQL) and I want to send my files from my localhost to my staging and development servers in the most efficient and hassle-free way. I am currently convinced that the best way for me to approach this problem is to use this git branching model to organize my local git repo. From there, I will use the release branches to push to my staging server for testing. Once I am happy that the release code works on the staging server, I can then merge with my master branch and push that to my production server. Pushing to Staging Server: As noted in many introductory git posts, I could run into problems pushing into a non-bare repo, so, as suggested in this response, I plan to push the release branch to a bare repo on the server and have a post-receive hook that clones the bare repo to a non-bare repo that also acts as the web-hosted directory. Pushing to Production Server: Here's my newest source of confusion... In the response that I cited above, it made me curious as to why @Paul states that it's a completely different story when pushing to a live, development server. I guess I don't see the problem. Would it be safe and hassle-free to follow the same steps as above, but for the master branch? Where are the potential pit-falls? Config Files: With respect to configuration files that are unique to each environment (.htaccess, config.php, etc), it seems simplest to .gitignore each of those files in their respective repos on their respective servers. Can you see anything immediately wrong with this? Better solutions? Accessing Data: Finally, as I initially stated, the site uses MySQL databases to store data. How would you suggest I access that data (for testing purposes) from the staging server and localhost? I realize that I may have asked way too many questions for a single post, but since they're all related to the best way to set up this development scheme, I thought it was necessary.

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  • Java EE Website Planning Questions

    - by Tom Tresansky
    I'm a .NET programming who is soon moving to the Java EE world. I have plenty of experience with .NET web technologies, web services, WebForms and MVC. I am also very familiar with the Java language, and have written a few servlets and modified a couple of JSP pages, but I haven't touched EE yet. I'd like to set up a public website using Java EE so I can familiarize myself with whats current. I'm thinking just a technology playground at this point with no particular purpose in mind. What Java technologies are the current hotness for this sort of thing? (For example, if someone asked me what I'd recommend learning to set up a new .NET site, I'd say use ASP MVC instead of WebForms and recommend LINQ-to-SQL as a quick, simple and widely used ORM.) So, what I'd like to know is: Is there a recommended technology for the presentation layer? Is JSP considered a good approach, or is there anything cleaner/newer/more widespread? Is Hibernate still widely used for persistence? Is it obsolete? Is there anything better out there? (I've worked with NHibernate some, so I wouldn't be starting from scratch.) Is cheap Java EE web hosting available? What should I know being a .NET web developer moving to the Java world?

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  • mysql_real_escape_string() just makes an empty string?

    - by James P
    I am using a jQuery AJAX request to a page called like.php that connects to my database and inserts a row. This is the like.php code: <?php // Some config stuff define(DB_HOST, 'localhost'); define(DB_USER, 'root'); define(DB_PASS, ''); define(DB_NAME, 'quicklike'); $link = mysql_connect(DB_HOST, DB_USER, DB_PASS) or die('ERROR: ' . mysql_error()); $sel = mysql_select_db(DB_NAME, $link) or die('ERROR: ' . mysql_error()); $likeMsg = mysql_real_escape_string(trim($_POST['likeMsg'])); $timeStamp = time(); if(empty($likeMsg)) die('ERROR: Message is empty'); $sql = "INSERT INTO `likes` (like_message, timestamp) VALUES ('$likeMsg', $timeStamp)"; $result = mysql_query($sql, $link) or die('ERROR: ' . mysql_error()); echo mysql_insert_id(); mysql_close($link); ?> The problematic line is $likeMsg = mysql_real_escape_string(trim($_POST['likeMsg']));. It seems to just return an empty string, and in my database under the like_message column all I see is blank entries. If I remove mysql_real_escape_string() though, it works fine. Here's my jQuery code if it helps. $('#like').bind('keydown', function(e) { if(e.keyCode == 13) { var likeMessage = $('#changer p').html(); if(likeMessage) { $.ajax({ cache: false, url: 'like.php', type: 'POST', data: { likeMsg: likeMessage }, success: function(data) { $('#like').unbind(); writeLikeButton(data); } }); } else { $('#button_container').html(''); } } }); All this jQuery code works fine, I've tested it myself independently. Any help is greatly appreciated, thanks.

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  • Macro and array crossing

    - by Thomas
    I am having a problem with a lisp macro. I would like to create a macro which generate a switch case according to an array. Here is the code to generate the switch-case: (defun split-elem(val) `(,(car val) ',(cdr val))) (defmacro generate-switch-case (var opts) `(case ,var ,(mapcar #'split-elem opts))) I can use it with a code like this: (generate-switch-case onevar ((a . A) (b . B))) But when I try to do something like this: (defparameter *operators* '((+ . OPERATOR-PLUS) (- . OPERATOR-MINUS) (/ . OPERATOR-DIVIDE) (= . OPERATOR-EQUAL) (* . OPERATOR-MULT))) (defmacro tokenize (data ops) (let ((sym (string->list data))) (mapcan (lambda (x) (generate-switch-case x ops)) sym))) (tokenize data *operators*) I got this error: *** - MAPCAR: A proper list must not end with OPS. But I don't understand why. When I print the type of ops I get SYMBOL I was expecting CONS, is it related? Also, for my function tokenize how many times the lambda is evaluated (or the macro expanded)?

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  • Unable to HTTP PUT with libcurl

    - by Jesse Beder
    I'm trying to PUT data using libcurl to mimic the command curl -u test:test -X PUT --data-binary @data.yaml "http://127.0.0.1:8000/foo/" which works correctly. My options look like: curl_easy_setopt(handle, CURLOPT_USERPWD, "test:test"); curl_easy_setopt(handle, CURLOPT_URL, "http://127.0.0.1:8000/foo/"); curl_easy_setopt(handle, CURLOPT_VERBOSE, 1); curl_easy_setopt(handle, CURLOPT_UPLOAD, 1); curl_easy_setopt(handle, CURLOPT_READFUNCTION, read_data); curl_easy_setopt(handle, CURLOPT_READDATA, &yaml); curl_easy_setopt(handle, CURLOPT_INFILESIZE, yaml.size()); curl_easy_perform(handle); I believe the read_data function works correctly, but if you ask, I'll post that code. I'm using Django with django-piston, and my update function is never called! (It is called when I use the command line version above.) libcurl's output is: * About to connect() to 127.0.0.1 port 8000 (#0) * Trying 127.0.0.1... * connected * Connected to 127.0.0.1 (127.0.0.1) port 8000 (#0) * Server auth using Basic with user 'test' > PUT /foo/ HTTP/1.1 Authorization: Basic dGVzdDp0ZXN0 Host: 127.0.0.1:8000 Accept: */* Content-Length: 244 Expect: 100-continue * Done waiting for 100-continue ** this is where my read_data handler confirms: read 244 bytes ** * HTTP 1.0, assume close after body < HTTP/1.0 400 BAD REQUEST < Date: Thu, 13 May 2010 08:22:52 GMT < Server: WSGIServer/0.1 Python/2.5.1 < Vary: Authorization < Content-Type: text/plain < Bad Request* Closing connection #0

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  • PHP Facebook Cronjob with offline access

    - by Mohamed Salem
    1:the code to greet the user, ask for his permission and store his session data so that we can use a cronjob with his session data afterwards. <?php $db_server = "localhost"; $db_username = "username"; $db_password = "password"; $db_name = "databasename"; #go to line 85, the script actually starts there mysql_connect($db_server,$db_username,$db_password); mysql_select_db($db_name); #you have to create a database to store session values. #if you do not know what columns there should be look at line 76 to see column names. #make them all varchars # Now lets load the FB GRAPH API require './facebook.php'; // Create our Application instance. global $facebook; $facebook = new Facebook(array( 'appId' => '121036530138', 'secret' => '9bbec378147064', 'cookie' => false,)); # Lets set up the permissions we need and set the login url in case we need it. $par['req_perms'] = "friends_about_me,friends_education_history,friends_likes, friends_interests,friends_location,friends_religion_politics, friends_work_history,publish_stream,friends_activities, friends_events, friends_hometown,friends_location ,user_interests,user_likes,user_events, user_about_me,user_status,user_work_history,read_requests, read_stream,offline_access,user_religion_politics,email,user_groups"; $loginUrl = $facebook->getLoginUrl($par); function save_session($session){ global $facebook; # OK lets go to the database and see if we have a session stored $sid=mysql_query("Select access_token from facebook_user WHERE uid =".$session['uid']); $session_id=mysql_fetch_row($sid); if (is_array($session_id)) { # We have a stored session, but is it valid? echo " We have a session, but is it valid?"; try { $attachment = array('access_token' => $session_id[0]); $ret_code=$facebook->api('/me', 'GET', $attachment); } catch (Exception $e) { # We don't have a good session so echo " our old session is not valid, let's delete saved invalid session data "; $res = mysql_query("delete from facebook_user WHERE uid =".$session['uid']); #save new good session #to see what is our session data: print_r($session); if (is_array($session)) { $sql="insert into facebook_user (session_key,uid,expires,secret,access_token,sig) VALUES ('".$session['session_key']."','".$session['uid']."','". $session['expires']."','". $session['secret'] ."','" . $session['access_token']."','". $session['sig']."');"; $res = mysql_query($sql); return $session['access_token']; } # this should never ever happen echo " Something is terribly wrong: Our old session was bad, and now we cannot get the new session"; return; } echo " Our old stored session is valid "; return $session_id[0]; } else { echo " no stored session, this means the user never subscribed to our application before. "; # let's store the session $session = $facebook->getSession(); if (is_array($session)) { # Yes we have a session! so lets store it! $sql="insert into facebook_user (session_key,uid,expires,secret,access_token,sig) VALUES ('".$session['session_key']."','".$session['uid']."','". $session['expires']."','". $session['secret'] ."','". $session['access_token']."','". $session['sig']."');"; $res = mysql_query($sql); return $session['access_token']; } } } #this is the first meaningful line of this script. $session = $facebook->getSession(); # Is the user already subscribed to our application? if ( is_null($session) ) { # no he is not #send him to permissions page header( "Location: $loginUrl" ); } else { #yes, he is already subscribed, or subscribed just now #in case he just subscribed now, save his session information $access_token=save_session($session); echo " everything is ok"; # write your code here to do something afterwards } ?> error Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/content/28/9687528/html/ss/src/indexx.php:1) in /home/content/28/9687528/html/ss/src/facebook.php on line 49 Fatal error: Call to undefined method Facebook::getSession() in /home/content/28/9687528/html/ss/src/indexx.php on line 86 2:A cronjob template that reads the stored session of a user from database, uses his session data to work on his behalf, like reading status posts or publishing posts etc. <?php $db_server = "localhost"; $db_username = "username"; $db_password = "pass"; $db_name = "database"; # Lets connect to the Database and set up the table $link = mysql_connect($db_server,$db_username,$db_password); mysql_select_db($db_name); # Now lets load the FB GRAPH API require './facebook.php'; // Create our Application instance. global $facebook; $facebook = new Facebook(array( 'appId' => 'appid', 'secret' => 'secret', 'cookie' => false, )); function get_check_session($uidCheck){ global $facebook; # This function basically checks for a stored session and if we have one it returns it # OK lets go to the database and see if we have a session stored $sid=mysql_query("Select access_token from facebook_user WHERE uid =".$uidCheck); $session_id=mysql_fetch_row($sid); if (is_array($session_id)) { # We have a session # but, is it valid? try { $attachment = array('access_token' => $session_id[0],); $ret_code=$facebook->api('/me', 'GET', $attachment); } catch (Exception $e) { # We don't have a good session so echo " User ".$uidCheck." removed the application, or there is some other access problem. "; # let's delete stored data $res = mysql_query("delete from facebook_user where WHERE uid =".$uidCheck); return; } return $session_id[0]; } else { # "no stored session"; echo " error:newsFeedcrontab.php No stored sessions. This should not have happened "; } } # get all users that have given us offline access $users = getUsers(); foreach($users as $user){ # now for each user, check if they are still subscribed to our application echo " Checking user".$user; $access_token=get_check_session($user); # If we've not got an access_token we actually need to login. # but in the crontab, we just log the error, there is no way we can find the user to give us permission here. if ( is_null($access_token) ) { echo " error: newsFeedcrontab.php There is no access token for the user ".$user." "; } else { #we are going to read the newsfeed of user. There are user's friends' posts in this newsfeed try{ $attachment = array('access_token' => $access_token); $result=$facebook->api('/me/home', 'GET', $attachment); }catch(Exception $e){ echo " error: newsfeedcrontab.php, cannot get feed of ".$user.$e; } #do something with the result here #but what does the result look like? #go to http://developers.facebook.com/docs/reference/api/user/ and click on the "home" link under connections #we can also read the home of user. Home is the wall of the user who has given us offline access. try{ $attachment = array('access_token' => $access_token); $result=$facebook->api('/me/feed', 'GET', $attachment); }catch(Exception $e){ echo " error: newsfeedcrontab.php, cannot get wall of ".$user.$e; } #do something with the result here # #but what does the result look like? #go to http://developers.facebook.com/docs/reference/api/user/ and click on the "feed" link under connections } } function getUsers(){ $sql = "SELECT distinct(uid) from facebook_user Where 1"; $result = mysql_query($sql); while($row = mysql_fetch_array($result)){ $rows [] = $row['uid']; } print_r($rows); return $rows; } mysql_close($link); ?> error Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/content/28/9687528/html/ss/src/cron.php:1) in /home/content/28/9687528/html/ss/src/facebook.php on line 49 Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /home/content/28/9687528/html/ss/src/cron.php on line 110 Warning: Invalid argument supplied for foreach() in /home/content/28/9687528/html/ss/src/cron.php on line 64

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  • PHP header redirection does not reload <iframe> in IE

    - by Marco Demaio
    When displaying data from DB usually I'm in this situation I'm in page A.php that shows data from DB, user performs some action (like edit/delete etc) and page B.php is loaded to perform the action, once page B performed the action, it redirects browser to page A, page A is auto reloaded during step (3) therefor it shows an updated situation of the data In order to make page B to redirect to page A i use a simple PHP header("Location: " . "A.php", TRUE, 302); This works well in all situations, except when pages A.php is displaied into an <iframe>: in such a case it does not reload (step 4 does not get done). This seems to happen only in IE7 (don't know about IE8), it works perfectly on FF/Safari. And only when using an <iframe>, if page A.php is not in <iframe> it gest refreshed also in IE7. In order to solve this I simply added a couple of headers in page A.php to set it to not be cached: header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1 header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past But I was curious if you might have experienced the same issue too in the past, and if you good give me some advice about this?

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  • Bitwise operators and converting an int to 2 bytes and back again.

    - by aKiwi
    first time user, Hi guys! So hopefully someone can help.. My background is php so entering the word of lowend stuff like, char is bytes, which are bits.. which is binary values.. etc is taking some time to get the hang of ;) What im trying to do here is sent some values from an Ardunio board to openFrameWorks (both are c++). What this script currently does (and works well for one sensor i might add) when asked for the data to be sent is.. int value_01 = analogRead(0); // which outputs between 0-1024 unsigned char val1; unsigned char val2; //some Complicated bitshift operation val1 = value_01 &0xFF; val2 = (value_01 >> 8) &0xFF; //send both bytes Serial.print(val1, BYTE); Serial.print(val2, BYTE); Apparently this is the most reliable way of getting the data across.. So now that it is send via serial port, the bytes are added to a char string and converted back by.. int num = ( (unsigned char)bytesReadString[1] << 8 | (unsigned char)bytesReadString[0] ); So to recap, im trying to get 4 sensors worth of data (which im assuming will be 8 of those serialprints?) and to have int num_01 - num_04... at the end of it all. Im assuming this (as with most things) might be quite easy for someone with experience in these concepts.. Any help would be greatly appreciated. Thanks

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  • Why the HelloWorld of opennlp library works fine on Java but doesn't work with Jruby?

    - by 0x90
    I am getting this error: SyntaxError: hello.rb:13: syntax error, unexpected tIDENTIFIER public HelloWorld( InputStream data ) throws IOException { The HelloWorld.rb is: require "java" import java.io.FileInputStream; import java.io.InputStream; import java.io.IOException; import opennlp.tools.postag.POSModel; import opennlp.tools.postag.POSTaggerME; public class HelloWorld { private POSModel model; public HelloWorld( InputStream data ) throws IOException { setModel( new POSModel( data ) ); } public void run( String sentence ) { POSTaggerME tagger = new POSTaggerME( getModel() ); String[] words = sentence.split( "\\s+" ); String[] tags = tagger.tag( words ); double[] probs = tagger.probs(); for( int i = 0; i < tags.length; i++ ) { System.out.println( words[i] + " => " + tags[i] + " @ " + probs[i] ); } } private void setModel( POSModel model ) { this.model = model; } private POSModel getModel() { return this.model; } public static void main( String args[] ) throws IOException { if( args.length < 2 ) { System.out.println( "HelloWord <file> \"sentence to tag\"" ); return; } InputStream is = new FileInputStream( args[0] ); HelloWorld hw = new HelloWorld( is ); is.close(); hw.run( args[1] ); } } when running ruby HelloWorld.rb "I am trying to make it work" when I run the HelloWorld.java "I am trying to make it work" it works perfectly, of course the .java doesn't contain the require java statement. EDIT: I followed the following steps. The output for jruby -v : jruby 1.6.7.2 (ruby-1.8.7-p357) (2012-05-01 26e08ba) (Java HotSpot(TM) 64-Bit Server VM 1.6.0_35) [darwin-x86_64-java]

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  • Class design when working with dataset

    - by MC
    If you have to retrieve data from a database and bring this dataset to the client, and then allow the user to manipulate the data in various ways before updating the database again, what is a good class design for this if the data tables will not have a 1:1 relationship with the class objects? Here are some I came up with: Just manipulate the DataSet itself on the client and then send it back to the database as is. This will work though obviously the code will be very dirty and not well-structured. Same as #1, but wrap the dataset code around classes. What I mean is that you may have a class that takes a dataset or a datatable in its constructor, and then provides public methods and properties to simplify the code. Inside these methods and properties it will be reading or manipulating the dataset. To update the database afterwards will be easy because you already have the updated dataset. Get rid of the dataset entirely on the client, convert to objects, then convert back to a dataset when needing to update the database. Is there any good resources where I can find information on this?

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  • Twitter API Rate Limit - Overcoming on an unauthenticated JSON Get with Objective C?

    - by Cian
    I see the rate limit is 150/hr per IP. This'd be fine, but my application is on a mobile phone network (with shared IP addresses). I'd like to query twitter trends, e.g. GET /trends/1/json. This doesn't require authorization, however what if the user first authorized with my application using OAuth, then hit the JSON API? The request is built as follows: - (void) queryTrends:(NSString *) WOEID { NSString *urlString = [NSString stringWithFormat:@"http://api.twitter.com/1/trends/%@.json", WOEID]; NSURL *url = [NSURL URLWithString:urlString]; NSURLRequest *theRequest=[NSURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10.0]; NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self startImmediately:YES]; if (theConnection) { // Create the NSMutableData to hold the received data. theData = [[NSMutableData data] retain]; } else { NSLog(@"Connection failed in Query Trends"); } //NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlString]]; } I have no idea how I'd build this request as an authenticated one however, and haven't seen any examples to this effect online. I've read through the twitter OAuth documentation, but I'm still puzzled as to how it should work. I've experimented with OAuth using Ben Gottlieb's prebuild library, and calling this in my first viewDidLoad: OAuthViewController *oAuthVC = [[OAuthViewController alloc] initWithNibName:@"OAuthTwitterDemoViewController" bundle:[NSBundle mainBundle]]; // [self setViewController:aViewController]; [[self navigationController] pushViewController:oAuthVC animated:YES]; This should store all the keys required in the app's preferences, I just need to know how to build the GET request after authorizing! Maybe this just isn't possible? Maybe I'll have to proxy the requests through a server side application? Any insight would be appreciated!

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  • What algorithms compute directions from point A to point B on a map?

    - by A. Rex
    How do map providers (such as Google or Yahoo! Maps) suggest directions? I mean, they probably have real-world data in some form, certainly including distances but also perhaps things like driving speeds, presence of sidewalks, train schedules, etc. But suppose the data were in a simpler format, say a very large directed graph with edge weights reflecting distances. I want to be able to quickly compute directions from one arbitrary point to another. Sometimes these points will be close together (within one city) while sometimes they will be far apart (cross-country). Graph algorithms like Dijkstra's algorithm will not work because the graph is enormous. Luckily, heuristic algorithms like A* will probably work. However, our data is very structured, and perhaps some kind of tiered approach might work? (For example, store precomputed directions between certain "key" points far apart, as well as some local directions. Then directions for two far-away points will involve local directions to a key points, global directions to another key point, and then local directions again.) What algorithms are actually used in practice? PS. This question was motivated by finding quirks in online mapping directions. Contrary to the triangle inequality, sometimes Google Maps thinks that X-Z takes longer and is farther than using an intermediate point as in X-Y-Z. But maybe their walking directions optimize for another parameter, too? PPS. Here's another violation of the triangle inequality that suggests (to me) that they use some kind of tiered approach: X-Z versus X-Y-Z. The former seems to use prominent Boulevard de Sebastopol even though it's slightly out of the way. (Edit: this example doesn't work anymore, but did at the time of the original post. The one above still works as of early November 2009.)

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  • Issue with Multiple Text Fields and SharedObject Storing

    - by user1662660
    I'm currently working on an AIR for iOS application in Flash CS6. I'm trying to store multiple pieces of data from various text inputs; i.e "name_txt", "number_txt" etc. I have the following code working for a local save file; import flash.events.Event; import flash.desktop.NativeApplication; import flash.events.Event; var n1:String = so.data.Number1; var so:SharedObject = SharedObject.getLocal("TravelPal"); emerg1.text = n1; emerg1.addEventListener(Event.CHANGE, updateEmerg1); function updateEmerg1 (e:Event):void { so.data.Number1 = emerg1.text; so.flush(); } NativeApplication.nativeApplication.addEventListener(Event.EXITING, onExit); function onExit(e:Event):void { so.flush(); } Now as soon as I create multiple text inputs and attempt to store them in my SharedObject, the whole system just falls apart. None of the text gets saved, even the previously working ones. I'm pretty new to ShardObject usage. What am I missing here? Is this a good way to go about storing multiple text inputs?

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  • How to create closed areas (convex polygons) from set of line segments ?

    - by Marten
    The following problem is in 2D, so some simplifications can be made when suggesting answers. I need to create closed areas (defined either by line segments or just set of points - convex polygon) from a set of points/line segments. Basically I used Voronoi to generate "roads". Then I changed some of the data. Now I need a way to loop through that data (which is still line segments but doesn't comply with Voronoi anymore) and generate "neigbourhoods" that are bordered with the "roads". I looked at some graph diagrams and shortest path theories, but I could not figure it out. Logically it could be done by starting at left edge from one point, finding the way back to that point using the shortest path with available lines (using only clockwise directions). Then mark this line set down and remove from the data. Then you can repeat the same process and get all the areas like that. I tried to implement that but it did not get me anywhere as I could not figure out a way to write a C++ code that could do that. Problem was with choosing the most counterclockwise line from available lines from a specific point. All angle based math I did gave wrong answers because the way sin/cos are implemented in c++. So to summarize - if you can help me with a totally new approach to the problem its good, if not could you help me find a way to write the part of the code that finds the shortest clockwise path back to the beginning point using the line segment set as paths back. Thank you for your help!

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  • How should I organize complex SQL views in Rails?

    - by Benjamin Oakes
    I manage a research database with Ruby on Rails. The data that is entered is primarily used by scientists who prefer to have all the relevant information for a study in one single massive table for use in their statistics software of choice. I'm currently presenting it as CSV, as it's very straightforward to do and compatible with the tools people want to use. I've written many views (the SQL kind, not the Rails HTML/ERB kind) to make the output they expect a reality. Some of these views are quite large and have a fair amount of complexity behind them. I wrote them in SQL because there are many calculations and comparisons that are more easily done with SQL. They're currently loaded into the database straight from a file named views.sql. To get the requested data, I do a select * from my_view;. The views.sql file is getting quite large. Part of the problem is that we're still figuring out what the data we collect means, so there's a lot of changes being made to the views all the time -- and a ton of them are being created. Many of them need to be repeatable. I've recently run into issues organizing and testing these views. Rails works great for user interface stuff and business logic, but I'm not aware of much existing structure for handling the reporting we require. Some options I've thought of: Should I move them into the most relevant models somehow? Several of the views interact with each other, which makes this situation more complex than just doing a single find_by_sql, so I don't know if they should only be part of the model. Perhaps they should be treated as a "view" in the MVC sense? (That is, they could be moved into app/views/ and live alongside the HTML, perhaps as files named something like my_view.csv.sql which return CSV.) How would you deal with a complex reporting problem like this?

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  • Update Options on Existing jQuery Object

    - by Vince Kronlein
    I'm using Bootstrap and DataTables in my app and I have a default initializer for tables based on class. I can just add the class data-table to the table and it gets instantiated with the default values I want. I'd like to know how to change or update specific options based on a specific table. if ($.fn.dataTable) { $('.data-table').dataTable( { sDom: "R<'row'<'span6'l><'span6'f>r>t<'row'<'span6'i><'span6'p>>", sPaginationType: "bootstrap", oLanguage: { "sLengthMenu": "_MENU_ &nbsp; records per page" }, aoColumnDefs: [ { "bSortable": false, "aTargets": [ 0 ] } ] }); } All my data tables have a checkbox in the first column so the above removal of sorting works for all of them. But I'd like to be able to update the aoColumnDefs on a table by table basis so I can add other columns that I don't want sorted. So let's say I have a table: $('#member-list'), how do I access this object and update it's datatables options in jQuery? I can't find any reference or help anywhere. Thanks a lot! -V

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  • setBit java method using bit shifting and hexadecimal code - question

    - by somewhat_confused
    I am having trouble understanding what is happening in the two lines with the 0xFF7F and the one below it. There is a link here that explains it to some degree. http://www.herongyang.com/java/Bit-String-Set-Bit-to-Byte-Array.html I don't know if 0xFF7FposBit) & oldByte) & 0x00FF are supposed to be 3 values 'AND'ed together or how this is supposed to be read. If anyone can clarify what is happening here a little better, I would greatly appreciate it. private static void setBit(byte[] data, final int pos, final int val) { int posByte = pos/8; int posBit = pos%8; byte oldByte = data[posByte]; oldByte = (byte) (((0xFF7F>>posBit) & oldByte) & 0x00FF); byte newByte = (byte) ((val<<(8-(posBit+1))) | oldByte); data[posByte] = newByte; } passed into this method as parameters from a selectBits method was setBit(out,i,val); out = is byte[] out = new byte[numOfBytes]; (numOfBytes can be 7 in this situation) i = which is number [57], the original number from the PC1 int array holding the 56-integers. val = which is the bit taken from the byte array from the getBit() method.

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  • Converting ntext to nvcharmax(max) - Getting around size limitation

    - by Overflew
    Hi all, I'm trying to change an existing SQL NText column to nvcharmax(max), and encountering an error on the size limit. There's a large amount of existing data, some of which is more than the 8k limit, I believe. We're looking to convert this, so that the field is searchable in LINQ. The 2x SQL statements I've tried are: update Table set dataNVarChar = convert(nvarchar(max), dataNtext) where dataNtext is not null update Table set dataNVarChar = cast(dataNtext as nvarchar(max)) where dataNtext is not null And the error I get is: Cannot create a row of size 8086 which is greater than the allowable maximum row size of 8060. This is using SQL Server 2008. Any help appreciated, Thanks. Update / Solution: The marked answer below is correct, and SQL 2008 can change the column to the correct data type in my situation, and there are no dramas with the LINQ-utilising application we use on top of it: alter table [TBL] alter column [COL] nvarchar(max) I've also been advised to follow it up with: update [TBL] set [COL] = [COL] Which completes the conversion by moving the data from the lob structure to the table (if the length in less than 8k), which improves performance / keeps things proper.

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  • Rails runner command not saving to cache

    - by mark
    Hi I'm having a bit of a problem with a cron task generated by rails whenever plugin that should store remote data in the rails cache for display. What I have is this: schedule.rb set :path, '/var/www/apps/tuexplore/current' every 1.hour do runner "Weather.cache_remote", :environment => :production end calls this model class Weather def self.cache_remote Rails.cache.write('weather_data', Net::HTTP.get_response(URI.parse(WEATHER_URL)).body) end end Calling whenever returns this PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/home/deploy/.gem/ruby/1.8/bin 0 * * * * /var/www/apps/tuexplore/current/script/runner -e production "Weather.cache_remote" This doesn't work. Calling the weather model method from a controller works fine, but I need to schedule it hourly. The cron task causes a "Cache write: weather_data" entry to appear in the production log but data isn't stored nor output into the page. Additional information, I can log into production console and run Weather.cache_remote, then read the data from the rails cache. I'd be really appreciative if someone could point out the error of my ways. If further explanation is needed please ask. Thanks in advance for any pointers.

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  • Hashing the state of a complex object in .NET

    - by Jan
    Some background information: I am working on a C#/WPF application, which basically is about creating, editing, saving and loading some data model. The data model contains of a hierarchy of various objects. There is a "root" object of class A, which has a list of objects of class B, which each has a list of objects of class C, etc. Around 30 classes involved in total. Now my problem is that I want to prompt the user with the usual "you have unsaved changes, save?" dialog, if he tries to exit the program. But how do I know if the data in current loaded model is actually changed? There is of course ways to solve this, like e.g. reloading the model from file and compare against the one in memory value by value or make every UI control set a flag indicating the model has been changed. Now instead, I want to create a hash value based on the model state on load and generate a new value when the user tries to exit, and compare those two. Now the question: So inspired of that, I was wondering if there exist some way to generate a hash value from the (value)state of some arbitrary complex object? Preferably in a generic way, e.g. no need to apply attributes to each involved class/field. One idea could be to use some of .NET's serialization functionality (assuming it will work out-of-the-box in this case) and apply a hash function to the content of the resulting file. However, I guess there exist some more suitable approach. Thanks in advance.

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  • How can I intercept an exception occurred during serialization in WCF?

    - by bonomo
    I have a legit data object with all data contract / data member attributes. For some reason the WCF service crashes after the operation has completed and the result is passed as a return value. I believe it has something to do with WCF not being able to serialize that result properly. The test client doesn't say anything specific: The underlying connection was closed: The connection was closed unexpectedly. Server stack trace: at System.ServiceModel.Channels.HttpChannelUtilities.ProcessGetResponseWebException(WebException webException, HttpWebRequest request, HttpAbortReason abortReason) at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout) at System.ServiceModel.Channels.RequestChannel.Request(Message message, TimeSpan timeout) at System.ServiceModel.Dispatcher.RequestChannelBinder.Request(Message message, TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout) at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation) at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message) Exception rethrown at [0]: at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg) at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type) at IFacade.PickSecurities(String pattern, Int32 atMost) at FacadeClient.PickSecurities(String pattern, Int32 atMost) Inner Exception: The underlying connection was closed: The connection was closed unexpectedly. at System.Net.HttpWebRequest.GetResponse() at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout) I am in control of creating the instance of the service using a customized service host factory. I know I can set up trace listeners and check the logs, but it's a lot of hassle to do. So I would rather handle it explicitly on the server at the time it happens. So I how can I intercept that exception programmatically and return an appropriate fault meassage?

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  • Heavy Mysql operation & Time Constraints [closed]

    - by Rahul Jha
    There is a performance issue where that I have stuck with my application which is based on PHP & MySql. The application is for Data Migration where data has to be uploaded and after various processes (Cleaning from foreign characters, duplicate check, id generation) it has to be inserted into one central table and then to 5 different tables. There, an id is generated and that id has to be updated to central table. There are different sets of records and validation rules. The problem I am facing is that when I insert say(4K) rows file (containing 20 columns) it is working fine within 15 min it gets inserted everywhere. But, when I insert the same records again then at this time it is taking one hour to insert (ideally it should get inserted by marking earlier inserted data as duplicate). After going through the log file, I noticed is that there is a Mysql select statement where I am checking the duplicates and getting ID which are duplicates. Then I am calling a function inside for loop which is basically inserting records into 5 tables and updates id to central table. This Calling function is major time of whole process. P.S. The records has to be inserted record by record.. Kindly Suggest some solution.. //This is that sample code $query=mysql_query("SELECT DISTINCT p1.ID FROM table1 p1, table2 p2, table3 a WHERE p2.datatype =0 AND (p1.datatype =1 || p1.datatype=2) AND p2.ID =0 AND p1.ID = a.ID AND p1.coulmn1 = p2.column1 AND p1.coulmn2 = p2.coulmn2 AND a.coulmn3 = p2.column3"); $num=mysql_num_rows($query); for($i=0;$i<$num;$i++) { $f=mysql_result($query,$i,"ID"); //calling function RecordInsert($f); }

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  • PHP's openssl_sign generates different signature than SSCrypto's sign

    - by pascalj
    I'm writing an OS X client for a software that is written in PHP. This software uses a simple RPC interface to receive and execute commands. The RPC client has to sign the commands he sends to ensure that no MITM can modify any of them. However, as the server was not accepting the signatures I sent from my OS X client, I started investigating and found out that PHP's openssl_sign function generates a different signature for a given private key/data combination than the Objective-C SSCrypto framework (which is only a wrapper for the openssl lib): SSCrypto *crypto = [[SSCrypto alloc] initWithPrivateKey:self.localPrivKey]; NSData *shaed = [self sha1:@"hello"]; [crypto setClearTextWithData:shaed]; NSData *data = [crypto sign]; generates a signature like CtbkSxvqNZ+mAN... The PHP code openssl_sign("hello", $signature, $privateKey); generates a signature like 6u0d2qjFiMbZ+... (For my certain key, of course. base64 encoded) I'm not quite shure why this is happening and I unsuccessfully experimented with different hash-algorithms. As the PHP documentation states SHA1 is used by default. So why do these two functions generate different signatures and how can I get my Objective-C part to generate a signature that PHPs openssl_verify will accept? Note: I double checked that the keys and the data is correct!

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