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  • jQuery get request against Sinatra does not get text

    - by jerhinesmith
    I have a very simple sinatra site that I'm trying to access via ajax through jQuery. To keep things incredibly simple, this code snippet: get '/behavior_count' do "60" end which returns "60" in the browser, shows up as an empty string when attempting to access the site via $.get in jQuery. The strange part is in Firebug, while the Response is empty, the HTTP header correctly describes Content-Length as 2, and I can see the request show up on the server. Is there something specific to Sinatra that isn't returning my data, or am I not using jQuery correctly? If it helps, I also tried this code: get '/behavior_count' do content_type 'text/plain', :charset => 'utf-8' "60" end and my jQuery looks like $.get('http://mysite:4567/behavior_count'); // Ignore the response, but // watch the request in firebug Any ideas?

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  • 2 (or more) ComboBoxes dependent on each other

    - by Mcad001
    Hi, I have an Organisation entity and a Region entity. An object of type Organisation can have one or more Region objects connected to it, thus I have a foreign key in my Region entity to the Organisation Entity. The Organisation and Region objects are pulled from my database using WCF RIA and entity framework. I want to put the Organisation objects in one ComboBox and the Region objects in another ComboBox, and when selecting an organsation having the ComboBox for Region objects automatically only showing regions that are connected to the selected organisation. Should be pretty basic, but the way I've designed it right now it doesnt work at all. So, any hint to how I can achive this? A simple simple codeexample is much appreciated! (I'm using SL4,WCF RIA MVVM)

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  • Repository, Service or Domain object - where does logic belong?

    - by betitall
    Take this simple, contrived example: UserRepository.GetAllUsers(); UserRepository.GetUserById(); Inevitably, I will have more complex "queries", such as: //returns users where active=true, deleted=false, and confirmed = true GetActiveUsers(); I'm having trouble determining where the responsibility of the repository ends. GetActiveUsers() represents a simple "query". Does it belong in the repository? How about something that involves a bit of logic, such as: //activate the user, set the activationCode to "used", etc. ActivateUser(string activationCode);

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  • output all data from db to a php page

    - by Sarit
    Hi, I'm a real beginner with PHP & mysql. Just for studying and for a simple example at school I would like to work this simple query and possibly output all the rows (or maybe even one) to a very basic output on a php page: <?php $user= "root"; $host="localhost"; $password=""; $database = "PetCatalog"; $cxn = mysqli_connect($host,$user,$password,$database) or die ("couldn’t connect to server"); $query = "SELECT * FROM Pet"; $result = mysql_query($cxn,$query) or die ("Couldn’t execute query."); $row = mysqli_fetch_assoc($result); echo "$result"; ?> this is the error message i've been getting: Warning: mysql_query() expects parameter 1 to be string, object given in C:\xampplite\htdocs\myblog\query.php on line 18 Couldn’t execute query. What should I do? Thanks!

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  • Crowdsourcing translation for mobile developers?

    - by superg
    I am developing applications for mobile phones with different operating systems (Android, Symbian, iPhone). Applications are sold internationally so they need to be translated to different languages in addition to english version. I assume most mobile developers do the translations using some paid external service each time. This approach does not look very cost-effective to me. Would it make sense to have a website where simple translations would be done using crowdsourcing (other developers)? Most strings in mobile applications are very simple and short, for example "OK, "Cancel", "Are you sure?", "Please enter your password". Also the same strings are used in hundreds of applications. Instead of paying for translating all strings, developers could save money by only buying their difficult application specific translations. Does anyone agree with this idea? I have seen many opensource projects doing the translations succesfully using volunteers.

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  • How to pass or display mySQL data based on subscription or billing

    - by spm
    I want to build a PHP based site where, the user can view data based on the types of data they've paid for. Allow me to use something simple for an example. Let's say historical data for basketball was not readily available but could be purchased. Simple information such as the Winner, Loser, Final score and date are all stored in a mySQL table. What would be involved so that, when the user logs in, they can only see the historical data they have paid for. My theories so far about the architecture: I imagined a mySQL table storing True or False values for all historical game data they have paid for. Based on this, a 'data chart' object enables the user to view all data within their mySQL row which has a value of 'true.' Follow ups: Assuming I am correct, what methods are popular or practical for this type of service.

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  • javascript error of unterminated string

    - by OM The Eternity
    I want pass a parameter of javascript functiona which is a string. This javascript function is a hintbox on mousehover.. and the string i am using is like this: Hemmed Finish: Every side/edge (1/2" to 2") of the banner are folded and glued (special vinyl solution) or heat pressed. This is the most common and best finish option. Stitched Finish: Every side/edge (1" to 2") of the banner are folded in the back and stitched/sewed with white thread. This is not a common option as thread can be seen on the banner. Now in the hintbox on mousehover the above given text has to be display as it is displayed above along with the paragraph break.. But when i pass the above as parameter in that function along with appending some backslashes to recognise some punctuation, iots till gives me javascript error of unterminated string... I am doing this: onMouseover="showhint('Hemmed Finish\: Every side/edge \(1/2\'\' to 2\'\'\) of the banner are folded and glued \(special vinyl solution\) or heat pressed. This is the most common and best finish option.Stitched Finish\: Every side/edge \(1\'\' to 2\'\'\) of the banner are folded in the back and stitched/sewed with white thread. This is not a common option as thread can be seen on the banner', this, event, '250px')" pls could u help me in rectifying the issue...

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  • Creating a process in ASP.NET MVC controller

    - by GRKamath
    I have a requirement to run an application through my MVC controller. To get the installation path I used following link (I used answer provided by Fredrik Mörk). It worked and I could able to run the exe through a process. The problem occurred when I deployed this solution on IIS where it did not create the process as it was creating in local dev environment. Can anybody tell me how to create a windows process through a solution which is hosted on IIS ? private string GetPathForExe(string fileName) { private const string keyBase = @"SOFTWARE\Wow6432Node\MyApplication"; RegistryKey localMachine = Registry.LocalMachine; RegistryKey fileKey = localMachine.OpenSubKey(string.Format(@"{0}\{1}", keyBase, fileName)); object result = null; if (fileKey != null) { result = fileKey.GetValue("InstallPath"); } fileKey.Close(); return (string)result; } public void StartMyApplication() { Process[] pname = Process.GetProcessesByName("MyApplication"); if (pname.Length == 0) { string appDirectory = GetPathForExe("MyApplication"); Directory.SetCurrentDirectory(appDirectory); ProcessStartInfo procStartInfo = new ProcessStartInfo("MyApplication.exe"); procStartInfo.WindowStyle = ProcessWindowStyle.Hidden; Process proc = new Process(); proc.StartInfo = procStartInfo; proc.Start(); } }

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  • I have a bunch of template parameters that I want to hide from my users. How can I do this?

    - by Alex
    I have a superclass which is defined in terms of a few internal types it uses. Subclassing is performed as so: template <class InternalType1, class InternalType2> class Super { ... } class Sub : Super <interalTypeClass1, interalTypeClass2> { ... } But when I want to write a function that takes a pointer to the superclass, this happens : template <class InternalType1, class InternalType2> void function(Super<InternalType1, InternalType2>* in) { ... } The user really shouldn't know anything about the inside classes, and should really just concern himself with the use of the function. Some of these template lists become very very large, and expecting the user to pass them every time is wasteful, in my opinion. Any suggestions? EDIT: The function needs to know the internal types in use, so unless there is a way to access template types at compile time, I think there is no solution? Potential solution: Have each class do the following: #define SubTemplateArgs <SubTypeName, SubInternalType1, SubInternalType2> ?

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  • Displaying name instead of ID PHP MySQL

    - by Derek
    Hi, I need something simple; I have page where a user clicks an author to see the books associated with that author. On my page displaying the list of books for the author, I want a simple HTML title saying: 'The books for: AUTHORNAME' I can get the page to display author ID but not the name. When the user clicks the link in the previous page of the author, it looks likes this: <a href="viewauthorbooks.php?author_id=<?php echo $row['author_id']?>"><?php echo $row['authorname']?></a> And then on the 'viewauthorbooks.php?author_id=23' I have declared this at the start: $author_id = $_GET['author_id']; $authorname = $_GET['authorname']; And finally, 'The books for: AUTHORNAME, where it says AUTHORNAME, I have this: echo $authorname (With PHP tags, buts its not letting me put them in!) And this doesnt show anything, however if I change it to author_id, it displays the correct author ID that has been clicked, but its not exactly user friendly!! Can anyone help me out!

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  • Round time to 5 minute nearest SQL Server

    - by Drako
    i don't know if it can be usefull to somebody but I went crazy looking for a solution and ended up doing it myself. Here is a function that (according to a date passed as parameter), returns the same date and approximate time to the nearest multiple of 5. It is a slow query, so if anyone has a better solution, it is welcome. A greeting. CREATE FUNCTION [dbo].[RoundTime] (@Time DATETIME) RETURNS DATETIME AS BEGIN DECLARE @min nvarchar(50) DECLARE @val int DECLARE @hour int DECLARE @temp int DECLARE @day datetime DECLARE @date datetime SET @date = CONVERT(DATETIME, @Time, 120) SET @day = (select DATEADD(dd, 0, DATEDIFF(dd, 0, @date))) SET @hour = (select datepart(hour,@date)) SET @min = (select datepart(minute,@date)) IF LEN(@min) > 1 BEGIN SET @val = CAST(substring(@min, 2, 1) as int) END else BEGIN SET @val = CAST(substring(@min, 1, 1) as int) END IF @val <= 2 BEGIN SET @val = CAST(CAST(@min as int) - @val as int) END else BEGIN IF (@val <> 5) BEGIN SET @temp = 5 - CAST(@min%5 as int) SET @val = CAST(CAST(@min as int) + @temp as int) END IF (@val = 60) BEGIN SET @val = 0 SET @hour = @hour + 1 END IF (@hour = 24) BEGIN SET @day = DATEADD(day,1,@day) SET @hour = 0 SET @min = 0 END END RETURN CONVERT(datetime, CAST(DATEPART(YYYY, @day) as nvarchar) + '-' + CAST(DATEPART(MM, @day) as nvarchar) + '-' + CAST(DATEPART(dd, @day) as nvarchar) + ' ' + CAST(@hour as nvarchar) + ':' + CAST(@val as nvarchar), 120) END

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  • Encryption in PHP leaves unwanted characters

    - by MichaelH
    I have made an encryption function which encrypts a simple value and stores it in the database. Here is the code to encrypt and decrypt: public function encrypt($string){ $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_ECB); $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND); $value = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $this->key256, $string, MCRYPT_MODE_ECB, $iv); $value = base64_encode($value); return $value; } public function decrypt($string){ $value = base64_decode($string); $value = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $this->key256, $value, MCRYPT_MODE_ECB); return $value; } When I encrypt a simple value such as 'Michael' and decrypt again, I get the value: Michael????????? Is there a reason I get all those question marks or a way to get rid of them?

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  • Java String to SHA1

    - by AeroDroid
    I'm trying to make a simple String to SHA1 converter in Java and this is what I've got... public static String toSHA1(byte[] convertme) { MessageDigest md = null; try { md = MessageDigest.getInstance("SHA-1"); } catch(NoSuchAlgorithmException e) { e.printStackTrace(); } return new String(md.digest(convertme)); } When I pass it toSHA1("password".getBytes()), I get "[?a?????%l?3~??." I know it's probably a simple encoding fix like UTF-8, but could someone tell me what I should do to get what I want which is "5baa61e4c9b93f3f0682250b6cf8331b7ee68fd8"? Or am I doing this completely wrong? Thanks a lot!

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  • Drupal module for complex hours of operation / office hours

    - by Eronarn
    Background: I am building a website in Drupal that links together a wide variety of social service providers for the purposes of discovery, collaboration, and all that good stuff. The goal is to make a website that is simple to browse for consumers of these services and simple to update for providers of these services. The beta has been very well received, but I want to switch to a different information schema before the site goes live. Specific question: I am looking for a module (or other solution) that... Stores this data in Drupal (i.e., no GCal) Supports a wide variety of repeats Is intuitive for people editing the node (no Cron-style interfaces, please!) I have looked into several modules on drupal.org and none seem to meet all of these criteria. I've also searched here, and while this question is similar: http://stackoverflow.com/questions/2794149/drupal-create-a-node-with-employee-working-hours my needs are too complex for the offered solution. Some of these providers have "hours" such as "the third Wednesday of every month", or "open during Winter months", or separate hotline & office hours. Likewise, the Date Repeat module doesn't cut it as stands currently. I'm comfortable hacking what I need into an existing module - I just don't want to duplicate effort! If you have a suggestion on what module might be a good starting point, I'd appreciate that input, too. Thanks. <3

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  • lists searches in SYB or uniplate haskell

    - by Chris
    I have been using uniplate and SYB and I am trying to transform a list For instance type Tree = [DataA] data DataA = DataA1 [DataB] | DataA2 String | DataA3 String [DataA] deriving Show data DataB = DataB1 [DataA] | DataB2 String | DataB3 String [DataB] deriving Show For instance, I would like to traverse my tree and append a value to all [DataB] So my first thought was to do this: changeDataB:: Tree -> Tree changeDataB = everywhere(mkT changeDataB') chanegDataB'::[DataB] -> [DataB] changeDataB' <add changes here> or if I was using uniplate changeDataB:: Tree -> Tree changeDataB = transformBi changeDataB' chanegDataB'::[DataB] -> [DataB] changeDataB' <add changes here> The problem is that I only want to search on the full list. Doing either of these searches will cause a search on the full list and all of the sub-lists (including the empty list) The other problem is that a value in [DataB] may generate a [DataB], so I don't know if this is the same kind of solution as not searching chars in a string. I could pattern match on DataA1 and DataB3, but in my real application there are a bunch of [DataB]. Pattern matching on the parents would be extensive. The other thought that I had was to create a data DataBs = [DataB] and use that to transform on. That seems kind of lame, there must be a better solution.

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  • Rails Model has_many with multiple foreign_keys

    - by Kenzie
    Relatively new to rails and trying to model a very simple family "tree" with a single Person model that has a name, gender, father_id and mother_id (2 parents). Below is basically what I want to do, but obviously I can't repeat the :children in a has_many (the first gets overwritten). class Person < ActiveRecord::Base belongs_to :father, :class_name => 'Person' belongs_to :mother, :class_name => 'Person' has_many :children, :class_name => 'Person', :foreign_key => 'mother_id' has_many :children, :class_name => 'Person', :foreign_key => 'father_id' end Is there a simple way to use has_many with 2 foreign keys, or maybe change the foreign key based on the object's gender? Or is there another/better way altogether? Thanks!

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  • Images not shown when publishing MVC application to virtual directory inside default web-site

    - by Michael Sagalovich
    Hi! I am developing an application using ASP.NET MVC 1 and VS2008. When I deploy it to the default web-site in my IIS6 on WinXP, all images are shown correctly, path to any given image is localhost/Content/ImagesUI/[image].[ext] When I deploy it to the virtual directory, created inside the same site, any image request returns IIS standard 404 error page, while the path is localhost/[DirectoryName]/Content/ImagesUI/[image].[ext] - that seems to be correct, true? I am mapping .* to c:\windows\microsoft.net\framework\v2.0.50727\aspnet_isapi.dll in both site and directory configurations. When this mapping is removed, images are shown correctly. However, all other URLs do not work, of course. When I am trying to open an image in browser using the URL to it, aspnet_wp.exe process is not even started (I restarted IIS to test it) - I merely get 404 or the image, depending on the presence of * mapping. Thus, I suppose it has nothing to do neither with routes registered for MVC, nor with ASP. The solution that I found is to make Content folder a virtual directory and remove * mapping from its configuration. While that's OK to some extent, I want a better solution, which will explain and eliminate the cause of the problem, not just workaround it. Thanks for your help!

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  • Extracting DCT coefficients from encoded images and video

    - by misha
    Is there a way to easily extract the DCT coefficients (and quantization parameters) from encoded images and video? Any decoder software must be using them to decode block-DCT encoded images and video. So I'm pretty sure the decoder knows what they are. Is there a way to expose them to whomever is using the decoder? I'm implementing some video quality assessment algorithms that work directly in the DCT domain. Currently, the majority of my code uses OpenCV, so it would be great if anyone knows of a solution using that framework. I don't mind using other libraries (perhaps libjpeg, but that seems to be for still images only), but my primary concern is to do as little format-specific work as possible (I don't want to reinvent the wheel and write my own decoders). I want to be able to open any video/image (H.264, MPEG, JPEG, etc) that OpenCV can open, and if it's block DCT-encoded, to get the DCT coefficients. In the worst case, I know that I can write up my own block DCT code, run the decompressed frames/images through it and then I'd be back in the DCT domain. That's hardly an elegant solution, and I hope I can do better. Presently, I use the fairly common OpenCV boilerplate to open images: IplImage *image = cvLoadImage(filename); // Run quality assessment metric The code I'm using for video is equally trivial: CvCapture *capture = cvCaptureFromAVI(filename); while (cvGrabFrame(capture)) { IplImage *frame = cvRetrieveFrame(capture); // Run quality assessment metric on frame } cvReleaseCapture(&capture); In both cases, I get a 3-channel IplImage in BGR format. Is there any way I can get the DCT coefficients as well?

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  • algorithm to find longest non-overlapping sequences

    - by msalvadores
    I am trying to find the best way to solve the following problem. By best way I mean less complex. As an input a list of tuples (start,length) such: [(0,5),(0,1),(1,9),(5,5),(5,7),(10,1)] Each element represets a sequence by its start and length, for example (5,7) is equivalent to the sequence (5,6,7,8,9,10,11) - a list of 7 elements starting with 5. One can assume that the tuples are sorted by the start element. The output should return a non-overlapping combination of tuples that represent the longest continuos sequences(s). This means that, a solution is a subset of ranges with no overlaps and no gaps and is the longest possible - there could be more than one though. For example for the given input the solution is: [(0,5),(5,7)] equivalent to (0,1,2,3,4,5,6,7,8,9,10,11) is it backtracking the best approach to solve this problem ? I'm interested in any different approaches that people could suggest. Also if anyone knows a formal reference of this problem or another one that is similar I'd like to get references. BTW - this is not homework. Edit Just to avoid some mistakes this is another example of expected behaviour for an input like [(0,1),(1,7),(3,20),(8,5)] the right answer is [(3,20)] equivalent to (3,4,5,..,22) with length 20. Some of the answers received would give [(0,1),(1,7),(8,5)] equivalent to (0,1,2,...,11,12) as right answer. But this last answer is not correct because is shorter than [(3,20)].

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  • How can I find the common ancestor of two nodes in a binary tree?

    - by Siddhant
    The Binary Tree here is not a Binary Search Tree. Its just a Binary Tree. The structure could be taken as - struct node { int data; struct node *left; struct node *right; }; The maximum solution I could work out with a friend was something of this sort - Consider this binary tree (from http://lcm.csa.iisc.ernet.in/dsa/node87.html) : The inorder traversal yields - 8, 4, 9, 2, 5, 1, 6, 3, 7 And the postorder traversal yields - 8, 9, 4, 5, 2, 6, 7, 3, 1 So for instance, if we want to find the common ancestor of nodes 8 and 5, then we make a list of all the nodes which are between 8 and 5 in the inorder tree traversal, which in this case happens to be [4, 9, 2]. Then we check which node in this list appears last in the postorder traversal, which is 2. Hence the common ancestor for 8 and 5 is 2. The complexity for this algorithm, I believe is O(n) (O(n) for inorder/postorder traversals, the rest of the steps again being O(n) since they are nothing more than simple iterations in arrays). But there is a strong chance that this is wrong. :-) But this is a very crude approach, and I'm not sure if it breaks down for some case. Is there any other (possibly more optimal) solution to this problem?

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  • Why aren't variables declared in "try" in scope in "catch" or "finally"?

    - by Jon Schneider
    In C# and in Java (and possibly other languages as well), variables declared in a "try" block are not in scope in the corresponding "catch" or "finally" blocks. For example, the following code does not compile: try { String s = "test"; // (more code...) } catch { Console.Out.WriteLine(s); //Java fans: think "System.out.println" here instead } In this code, a compile-time error occurs on the reference to s in the catch block, because s is only in scope in the try block. (In Java, the compile error is "s cannot be resolved"; in C#, it's "The name 's' does not exist in the current context".) The general solution to this issue seems to be to instead declare variables just before the try block, instead of within the try block: String s; try { s = "test"; // (more code...) } catch { Console.Out.WriteLine(s); //Java fans: think "System.out.println" here instead } However, at least to me, (1) this feels like a clunky solution, and (2) it results in the variables having a larger scope than the programmer intended (the entire remainder of the method, instead of only in the context of the try-catch-finally). My question is, what were/are the rationale(s) behind this language design decision (in Java, in C#, and/or in any other applicable languages)?

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  • Error in bisection method code in Matlab

    - by Amanda Collins
    I need to write a proper implementation of the bisection method, which means I must address all possible user input errors. Here is my code: function [x_sol, f_at_x_sol, N_iterations] = bisection(f, xn, xp, eps_f, eps_x) % solving f(x)=0 with bisection method % f is the function handle to the desired function, % xn and xp are borders of search, % f(xn)<0 and f(xp)>0 required, % eps_f defines how close f(x) should be to zero, % eps_x defines uncertainty of solution x if(f(xp) < 0) error('xp must be positive') end; if(f(xn)>0) error('xn must be negative') end; if (xn >= xp) error ('xn must be less than xp') end; xg=(xp+xn)/2; %initial guess fg=f(xg); % initial function evaluation N_iterations=1; while ( (abs(fg) > eps_f) & (abs(xg-xp) > eps_x) ) if (fg>0) xp=xg; else xn=xg; end xg=(xp+xn)/2; %update guess fg=f(xg); %update function evaluation N_iterations=N_iterations+1; end x_sol=xg; %solution is ready f_at_x_sol=fg; if (f_at_x_sol > eps_f) error('No convergence') end and here is the error message I receive when I try to test this in Matlab: >> bisection(x.^2, 2, -1, 1e-8, 1e-10) Attempted to access f(-1); index must be a positive integer or logical. Error in bisection (line 9) if(f(xp)<0) I was attempting to see if my error codes worked, but it doesn't look like they do. I get the same error when I try to test it on a function that should work.

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  • MySQL: Limit rows linked to each joined row

    - by SolidSnakeGTI
    Hello, Specifications: MySQL 4.1+ I've certain situation that requires certain result set from MySQL query, let's see the current query first & then ask my question: SELECT thread.dateline AS tdateline, post.dateline AS pdateline, MIN(post.dateline) FROM thread AS thread LEFT JOIN post AS post ON(thread.threadid = post.threadid) LEFT JOIN forum AS forum ON(thread.forumid = forum.forumid) WHERE post.postid != thread.firstpostid AND thread.open = 1 AND thread.visible = 1 AND thread.replycount >= 1 AND post.visible = 1 AND (forum.options & 1) AND (forum.options & 2) AND (forum.options & 4) AND forum.forumid IN(1,2,3) GROUP BY post.threadid ORDER BY tdateline DESC, pdateline ASC As you can see, mainly I need to select dateline of threads from 'thread' table, in addition to dateline of the second post of each thread, that's all under the conditions you see in the WHERE CLAUSE. Since each thread has many posts, and I need only one result per thread, I've used GROUP BY CLAUSE for that purpose. This query will return only one post's dateline with it's related unique thread. My questions are: How to limit returned threads per each forum!? Suppose I need only 5 threads -as a maximum- to be returned for each forum declared in the WHERE CLAUSE 'forum.forumid IN(1,2,3)', how can this be achieved. Is there any recommendations for optimizing this query (of course after solving the first point)? Notes: I prefer not to use sub-queries, but if it's the only solution available I'll accept it. Double queries not recommended. I'm sure there's a smart solution for this situation. Appreciated advice in advance :)

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  • C++: inheritance problem

    - by Helltone
    It's quite hard to explain what I'm trying to do, I'll try: Imagine a base class A which contains some variables, and a set of classes deriving from A which all implement some method bool test() that operates on the variables inherited from A. class A { protected: int somevar; // ... }; class B : public A { public: bool test() { return (somevar == 42); } }; class C : public A { public: bool test() { return (somevar > 23); } }; // ... more classes deriving from A Now I have an instance of class A and I have set the value of somevar. int main(int, char* []) { A a; a.somevar = 42; Now, I need some kind of container that allows me to iterate over the elements i of this container, calling i::test() in the context of a... that is: std::vector<...> vec; // push B and C into vec, this is pseudo-code vec.push_back(&B); vec.push_back(&C); bool ret = true; for(i = vec.begin(); i != vec.end(); ++i) { // call B::test(), C::test(), setting *this to a ret &= ( a .* (&(*i)::test) )(); } return ret; } How can I do this? I've tried two methods: forcing a cast from B::* to A::*, adapting a pointer to call a method of a type on an object of a different type (works, but seems to be bad); using std::bind + the solution above, ugly hack; changing the signature of bool test() so that it takes an argument of type const A& instead of inheriting from A, I don't really like this solution because somevar must be public.

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  • Integrate QT and OpenCV in Visual Studio

    - by user2891190
    Sorry If you feel that this is an already asked question. But I googled for more than 2 days any tried lots of solution which given through stackoverflow and referred lots of tutorials. But I couldn't get a proper idea. I am already working in a project which use c++(visual studio) with opencv which I am developing as my university project. I have developing this for last 2 months. But now I want to add a better UI.(Previously I considered only on the functionality) So I decided to move into QT. I'm new to QT. So I did some google search. I know that I can do this with the QT creator. But I want to do this in visual studio as the functionality of my project is bit complex. What I already know is I have to build opencv with Qt using cmake. I followed few tutorials. But most of the tutorials use mingw and QT creator. http://www.anlak.com/build-debug-opencv-vs2010/ Accoring to above tutorial I generated a visual studio project using cmake. But when I tried to open that solution file my visual studio becomes not-responding. I can't figure out the reason. I tried two days and I couldn't find a proper tutorial which describes integration of QT and opencv in visual studio. So can someone give me the instruction to integrate QT and Opencv in visual studio.

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