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  • Jquery, how to escape quotes

    - by Sandro Antonucci
    I'm using a simple jquery code that grabs html code form a tag and then puts this content into a form input <td class="name_cat" ><span class="name_cat">It&#039;s a &quot;test&quot; </span> (5)</td> jquery gets the content into span.name_catand returns it as It's a "test". So when I print this into an input it becomes <input value="It's a "test"" /> which as you can imagine will only show as It's a , the following double quote will close the value tag. What's the trick here to keep the original string while not showing utf8 code in the input? Jquery code $(".edit_cat").click(function(){ tr = $(this).parents("tr:first"); id_cat = $(this).attr("id"); td_name = tr.find(".name_cat"); span_name = tr.find("span.name_cat").html(); form = '<form action="/admin/controllers/edit_cat.php" method="post" >'+ '<input type="hidden" name="id_cat" value="'+id_cat+'" />'+ '<input type="text" name="name_cat" value="'+span_name+'" />'+ '<input type="submit" value="save" />'+ '</form>'; td_name.html(form); console.log(span_name); } ); I basically need html() not to decode Utf8

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  • How to change the handler position by dragging/single click on the slider

    - by Geetha
    Hi All, I am using the following files to create a slider. Problem:Needs double click to change the handler position first click: it move the handler but the following code is not working. a second later it return back to the previous position. second click on the handler in new position, before it moves back the following code is working. Needs: I want change the media player current position with the handler current position value by dragging the handler or single click on the new position of the slider. Ex: initial position of the handler: l-------------------------------- document.mediaPlayer.currentPosition = 0 After dragging it some other position ----------------------l---------- document.mediaPlayer.currentPosition = 125 Code: var endTime = document.mediaPlayer.SelectionEnd; $("#slider-constraints").slider({ animate: true, max: endTime, range: $R(0, endTime), value: 1, enforceConstraints: false, start:function(event,index){document.mediaPlayer.currentPosition=index.value; $('#slider-constraints').slider("constraints", [0, index.value]); $('#slider-constraints').slider("value", index.value);} }); window.setInterval(function() { $('#slider-constraints').slider("value", document.mediaPlayer.currentPosition); }, 4000);

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  • Setup for games animation: How do I know JFrame is finished setting itself up?

    - by Jokkel
    I'm using javax.swing.JFrame to draw game animations using double buffer strategy. First, I set up the frame. JFrame frame = new JFrame(); frame.setVisible(true); Now, I draw an object (let it be a circle, doesn't matter) like this. frame.createBufferStrategy(2); bufferStrategy = frame.getBufferStrategy(); Graphics g = bufferStrategy.getDrawGraphics(); circle.draw(g); bufferStrategy.show(); The problem is that the frame is not always fully set-up when the drawing takes place. Seems like JFrame needs up to three steps in resizing itself, until it reaches it's final size. That makes the drawing slide out of frame or hinders it to appear completely from time to time. I already managed to delay things using SwingUtilities.invokeLater(). While this improved the result, there are still times when the drawing slides away / looks prematurely draw. Any idea / strategy? Thanks in advance. EDIT: Ok thanks so far. I didn't mention that I write a little Pong game in the first place. Sorry for the confusion What I actually looked for was the right setup for accelerated game animations done in Java. While reading through the suggestions I found my question answered (though indirectly) here and this example made things clear for me. A resume for this might be that for animating game graphics in Java, the first step is to get rid of the GUI logic overhead.

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  • Session scoped bean as class attribute of Spring MVC Controller

    - by Sotirios Delimanolis
    I have a User class: @Component @Scope("session") public class User { private String username; } And a Controller class: @Controller public class UserManager { @Autowired private User user; @ModelAttribute("user") private User createUser() { return user; } @RequestMapping(value = "/user") public String getUser(HttpServletRequest request) { Random r = new Random(); user.setUsername(new Double(r.nextDouble()).toString()); request.getSession().invalidate(); request.getSession(true); return "user"; } } I invalidate the session so that the next time i got to /users, I get another user. I'm expecting a different user because of user's session scope, but I get the same user. I checked in debug mode and it is the same object id in memory. My bean is declared as so: <bean id="user" class="org.synchronica.domain.User"> <aop:scoped-proxy/> </bean> I'm new to spring, so I'm obviously doing something wrong. I want one instance of User for each session. How?

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  • C++ std::vector memory/allocation

    - by aaa
    from a previous question about vector capacity, http://stackoverflow.com/questions/2663170/stdvector-capacity-after-copying, Mr. Bailey said: In current C++ you are guaranteed that no reallocation occurs after a call to reserve until an insertion would take the size beyond the value of the previous call to reserve. Before a call to reserve, or after a call to reserve when the size is between the value of the previous call to reserve and the capacity the implementation is allowed to reallocate early if it so chooses. So, if I understand correctly, in order to assure that no relocation happens until capacity is exceeded, I must do reserve twice? can you please clarify it? I am using vector as a memory stack like this: std::vector<double> memory; memory.reserve(size); memory.insert(memory.end(), matrix.data().begin(), matrix.data().end()); // smaller than size size_t offset = memory.size(); memory.resize(memory.capacity(), 0); I need to guarantee that relocation does not happen in the above. thank you. ps: I would also like to know if there is a better way to manage memory stack in similar manner other than vector

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  • How can I serialize functions using JSON or some other serialization library?

    - by Oragamster
    I am trying to create a program that uses javascript to write a simple textadventure that I can then post on my blog and run on my iphone. I have run into a problem though. I was trying to make it so that my program would save it's state into cookies using JSON to convert it into strings and then post it into a cookie but then I realised that I couldn't serialize the functions that are on my item object. I was trying to make it so that my item would have an associative array that would contain the name of the use as the key and the function as the value. This worked well untill I tried to serialize it. I learned that I could create a JSON like serialization for functions by storing the body into a string and using escape charectors for the double quotes but for some reason I was unable to make my cookie with the function as the string stored. When I posted the cookie and then tried to get it back the string wasn't there. My code and the over all project are on my site if you want to look at that, though my full code including the item actions are not posted yet.

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  • Copy object using pointer (templates)

    - by Azodious
    How the push_back of stl::vector is implemented so it can make copy of any datatype .. may be pointer, double pointer and so on ... I'm implementing a template class having a function push_back almost similar to vector. Within this method a copy of argument should be inserted in internal memory allocated memory. but the argument is a pointer. (an object pointer). Can you pls tell how to create copy from pointer. so that if i delete the pointer in caller still the copy exists in my template class? Code base is as follows: template<typename T> class Vector { public: void push_back(const T& val_in) { T* a = *(new T(val_in)); m_pData[SIZE++] = a; } } Caller: Vector<MyClass*> v(3); MyClass* a = new MyClass(); a->a = 0; a->b = .5; v.push_back(a); delete a; Thanks.

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  • How to make paging start from 1 instead of 0 in ASP.NET MVC

    - by ssx
    I used the paging example of the Nerddinner tutorial. But I also wanted to add page Numbers, somehting like that: <<< 1 2 3 4 5 6 The code below works if i start my paging from 0, but not from 1. How can I fix this ? Here is my code: PaginatedList.cs public class PaginatedList<T> : List<T> { public int PageIndex { get; private set; } public int PageSize { get; private set; } public int TotalCount { get; private set; } public int TotalPages { get; private set; } public PaginatedList(IQueryable<T> source, int pageIndex, int pageSize) { PageIndex = pageIndex; PageSize = pageSize; TotalCount = source.Count(); TotalPages = (int) Math.Ceiling(TotalCount / (double)PageSize); this.AddRange(source.Skip(PageIndex * PageSize).Take(PageSize)); } public bool HasPreviousPage { get { return (PageIndex > 0); } } public bool HasNextPage { get { return (PageIndex+1 < TotalPages); } } } UserController.cs public ActionResult List(int? page) { const int pageSize = 20; IUserRepository userRepository = new UserRepository(); IQueryable<User> listUsers = userRepository.GetAll(); PaginatedList<User> paginatedUsers = new PaginatedList<User>(listUsers, page ?? 0, pageSize); return View(paginatedUsers); } List.cshtml @if (Model.HasPreviousPage) { @Html.RouteLink(" Previous ", "PaginatedUsers", new { page = (Model.PageIndex - 1) }) } @for (int i = 1; i <= Model.TotalPages; i++) { @Html.RouteLink(@i.ToString(), "PaginatedUsers", new { page = (@i ) }) } @if (Model.HasNextPage) { @Html.RouteLink(" Next ", "PaginatedUsers", new { page = (Model.PageIndex + 1) }) }

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  • Image rotate opecv error

    - by avd
    When I use this code to rotate the image, the destination image size remains same and hence the image gets clipped. Please provide me a way/code snippet to resize accordingly (like matlab does in imrotate) so that image does not get clipped and outlier pixels gets filled with all white instead of black. void imrotate(std::string imgPath,std::string angleStr,std::string outPath) { size_t found1,found2; found1=imgPath.find_last_of('/'); found2=imgPath.size()-4; IplImage* src=cvLoadImage(imgPath.c_str(), -1);; IplImage* dst; dst = cvCloneImage( src ); int angle = atoi(angleStr.c_str()); CvMat* rot_mat = cvCreateMat(2,3,CV_32FC1); CvPoint2D32f center = cvPoint2D32f( src->width/2, src->height/2 ); double scale = 1; cv2DRotationMatrix( center, angle, scale, rot_mat ); cvWarpAffine( src, dst, rot_mat); char angStr[4]; sprintf(angStr,"%d",angle); cvSaveImage(string(outPath+imgPath.substr(found1+1,found2-found1-1)+"_"+angStr+".jpg").c_str(),dst); cvReleaseImage(&src); cvReleaseImage(&dst); cvReleaseMat( &rot_mat ); } Original Image: Rotated Image:

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  • PHP syntax for postgresql Mixed-case table names

    - by yam
    I have a code below: <?php require "institution.php" /* in this portion, query for database connection is executed, and */ $institution= $_POST['institutionname']; $sCampID = 'SELECT ins_id FROM institution where ins_name= '$institution' '; $qcampID = pg_query($sCampID) or die("Error in query: $query." . pg_last_error($connection)); /* this portion outputs the ins_id */ ?> My database before has no mixed-case table names, that's why when I run this query, it shows no error at all. But because I've changed my database for some reasons, and it contains now mixed-case table names, i have to change the code above into this one: $sCampID = 'SELECT ins_id FROM "Institution" where ins_name= '$institution' '; where the Institution has to be double quoted. The query returned parse error. When i removed this portion: where ins_name= '$institution', no error occured. My question is how do I solve this problem where the table name which contains a mixed-case letter and a value stored in a variable ($institution in this case) will be combined in a single select statement? Your answers and suggestions will be very much appreciated.

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  • Set the amount of rows JList show (Java)

    - by Alex Cheng
    Hi all. Problem: I have a method that creates a list from the parsed ArrayList. I manage to show the list in the GUI, without scrollbar. However, I am having problem setting it to show only the size of ArrayList. Meaning, say if the size is 6, there should only be 6 rows in the shown List. Below is the code that I am using. I tried setting the visibleRowCount as below but it does not work. I tried printing out the result and it shows that the change is made. private void createSuggestionList(ArrayList<String> str) { int visibleRowCount = str.size(); System.out.println("visibleRowCount " + visibleRowCount); listForSuggestion = new JList(str.toArray()); listForSuggestion.setSelectionMode(ListSelectionModel.SINGLE_SELECTION); listForSuggestion.setSelectedIndex(0); listForSuggestion.setVisibleRowCount(visibleRowCount); System.out.println(listForSuggestion.getVisibleRowCount()); listScrollPane = new JScrollPane(listForSuggestion); MouseListener mouseListener = new MouseAdapter() { @Override public void mouseClicked(MouseEvent mouseEvent) { JList theList = (JList) mouseEvent.getSource(); if (mouseEvent.getClickCount() == 2) { int index = theList.locationToIndex(mouseEvent.getPoint()); if (index >= 0) { Object o = theList.getModel().getElementAt(index); System.out.println("Double-clicked on: " + o.toString()); } } } }; listForSuggestion.addMouseListener(mouseListener); textPane.add(listScrollPane); repaint(); } To summarize: I want the JList to show as many rows as the size of the parsed ArrayList, without a scrollbar. Any ideas? Please help. Thanks. Please let me know if a picture of the problem is needed in case I did not phrase my question correctly.

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  • How to strip out 0x0a special char from utf8 file using c# and keep file as utf8?

    - by user1013388
    The following is a line from a UTF-8 file from which I am trying to remove the special char (0X0A), which shows up as a black diamond with a question mark below: 2464577 ????? True s6620178 Unspecified <1?1009-672 This is generated when SSIS reads a SQL table then writes out, using a flat file mgr set to code page 65001. When I open the file up in Notepad++, displays as 0X0A. I'm looking for some C# code to definitely strip that char out and replace it with either nothing or a blank space. Here's what I have tried: string fileLocation = "c:\\MyFile.txt"; var content = string.Empty; using (StreamReader reader = new System.IO.StreamReader(fileLocation)) { content = reader.ReadToEnd(); reader.Close(); } content = content.Replace('\u00A0', ' '); //also tried: content.Replace((char)0X0A, ' '); //also tried: content.Replace((char)0X0A, ''); //also tried: content.Replace((char)0X0A, (char)'\0'); Encoding encoding = Encoding.UTF8; using (FileStream stream = new FileStream(fileLocation, FileMode.Create)) { using (BinaryWriter writer = new BinaryWriter(stream, encoding)) { writer.Write(encoding.GetPreamble()); //This is for writing the BOM writer.Write(content); } } I also tried this code to get the actual string value: byte[] bytes = { 0x0A }; string text = Encoding.UTF8.GetString(bytes); And it comes back as "\n". So in the code above I also tried replacing "\n" with " ", both in double quotes and single quotes, but still no change. At this point I'm out of ideas. Anyone got any advice? Thanks.

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  • How can i design a DB where the user can define the fields and types of a detail table in a M-D rela

    - by Simon
    My application has one table called 'events' and each event has approx 30 standard fields, but also user defined fields that could be any name or type, in an 'eventdata' table. Users can define these event data tables, by specifying x number of fields (either text/double/datetime/boolean) and the names of these fields. This 'eventdata' (table) can be different for each 'event'. My current approach is to create a lookup table for the definitions. So if i need to query all 'event' and 'eventdata' per record, i do so in a M-D relaitionship using two queries (i.e. select * from events, then for each record in 'events', select * from 'some table'). Is there a better approach to doing this? I have implemented this so far, but most of my queries require two distinct calls to the DB - i cannot simply join my master 'events' table with different 'eventdata' tables for each record in in 'events'. I guess my main question is: can i join my master table with different detail tables for each record? E.g. SELECT E.*, E.Tablename FROM events E LEFT JOIN 'E.tablename' T ON E._ID = T.ID If not, is there a better way to design my database considering i have no idea on how many user defined fields there may be and what type they will be.

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  • C++ CRTP question

    - by aaa
    following piece of code does not compile, the problem is in T::rank not be inaccessible (I think) or uninitialized in parent template. Can you tell me exactly what the problem is? is passing rank explicitly the only way? or is there a way to query tensor class directly? Thank you #include <boost/utility/enable_if.hpp> template<class T, // size_t N, class enable = void> struct tensor_operator; // template<class T, size_t N> template<class T> struct tensor_operator<T, typename boost::enable_if_c< T::rank == 4>::type > { tensor_operator(T &tensor) : tensor_(tensor) {} T& operator()(int i,int j,int k,int l) { return tensor_.layout.element_at(i, j, k, l); } T &tensor_; }; template<size_t N, typename T = double> // struct tensor : tensor_operator<tensor<N,T>, N> { struct tensor : tensor_operator<tensor<N,T> > { static const size_t rank = N; }; I know the workaround, however am interested in mechanics of template instantiation for self-education

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  • Can anyone provide a good "idiot's guide" to creating an installer in VS2008 (C#) Pro?

    - by paxdiablo
    I have Visual C# 2008 Professional and have developed the first half of a C# application (console mode) with the second half in progress now (GUI). I'm looking for an easy path to creating an installer for it. What are the steps that need to be taken to produce a professional installer? There's a similar question here regarding the Express edition but I have Pro, and I would like as much as possible to stick with just the standard VS stuff (if you think you can convince me that a third party installer creator is much better than a VS-only solution, give it a shot, by all means). Keep in mind that I have no interest in upgrading to VS2010 yet, even if it's a hundred times easier to create an installer. That can come later, when the revenue starts rolling in :-) Also be aware that the GUI component of this application is a totally separate executable from the console part. The console part is a simple "open file 1, do some work on it, write file 2" type and the GUI is a fairly standard "open file, do some stuff" beast so there's no tricky or wildly undocumented behaviour happening. Basically, I'm looking for (at least) the following: professional looking installer. ability to specify where the application files go. changes to the registry to allow double-clicks on my file extension to open the GUI app with the file as an argument. needs to install everything required (my stuff, .Net if required, and so on).

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  • Set registry to control working dir when associating file-type with application

    - by John
    I'm using Inno for an installer, and I want to associate a file type with my app: Root: HKCR; Subkey: ".rpl"; ValueType: string; ValueName: ""; ValueData: "MyReplay"; Flags: uninsdeletevalue; Root: HKCR; Subkey: "MyReplay"; ValueType: string; ValueName: ""; ValueData: "Replay File"; Flags: uninsdeletekey; Root: HKCR; Subkey: "MyReplay\DefaultIcon"; ValueType: string; ValueName: ""; ValueData: "{app}\bin\MyApp.ico,0"; Flags: uninsdeletekey; Root: HKCR; Subkey: "MyReplay\shell\open\command"; ValueType: string; ValueName: ""; ValueData: """{app}\bin\MyApp.exe"" ""%1"""; Flags: uninsdeletekey; Right now, double-clicking a .rpl file launches the app, but the working dir appears to be where the .rpl file is located, so the app crashes as it can't load any data. Is it posible to set the registry to control the start/working dir for file associations as well as the app that is launched? Or does my app itself need to be able to work around this?

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  • How can I create an instance of a class that I can use is more than one place in c#

    - by user1743574
    So I've been working on a class that details students of a university. I have one button that sets the details to a new instance of a class, and another to check if the student passed, through a method in my Class. The problem is that I create an instance of a class in the first button to add the values from what the user input, but I cannot use the second button to access the instance of the class created in the first button. private void button3_Click(object sender, EventArgs e) { Student student1 = new Student(); label1.Text = student1.text(); if (student1.hasPassed() == true) { passfailtextbox.Text = "Pass"; } else { passfailtextbox.Text = "Fail"; } } private void button1_Click(object sender, EventArgs e) { Student student1 = new Student(); student1.FirstName = firstnamebox.Text; student1.SecondName = secondnamebox.Text; student1.DateofBirth = DateTime.Parse(dobtextbox.Text).Date; student1.Course = coursetextbox.Text; student1.MatriculationNumber = int.Parse(matriculationtextbox.Text); student1.YearMark = double.Parse(yearmarktextbox.Text); } public Boolean hasPassed() { if (YearMark < 40) { return false; } else { return true; } } public string text() { return "Student" + " " + firstname + " " + secondname + " " + course + " " + dob.ToString() + " " + matriculationnumber.ToString() + " " + yearmark.ToString() ; }

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  • Making firefox refresh images faster

    - by Earlz
    I have a thing I'm doing where I need a webpage to stream a series of images from the local client computer. I have a very simple run here: http://jsbin.com/idowi/34 The code is extremely simple setTimeout ( "refreshImage()", 100 ); function refreshImage(){ var date = new Date() var ticks = date.getTime() $('#image').attr('src','http://127.0.0.1:2723/signature?'+ticks.toString()); setTimeout ("refreshImage()", 100 ); } Basically I have a signature pad being used on the client machine. We want for the signature to show up in the web page and for them to see themselves signing it within the web page(the pad does not have an LCD to show it to them right there). So I setup a simple local HTTP server which grabs an image of what the current state of the signature pad looks like and it gets sent to the browser. This has no problems in any browser(tested in IE7, 8, and Chrome) but Firefox where it is extremely laggy and jumpy and doesn't keep with the 10 FPS rate. Does anyone have any ideas on how to fix this? I've tried creating very simple double buffering in javascript but that just made things worse. Also for a bit more information it seems that Firefox is executing the javascript at the correct framerate as on the server the requests are coming in at a constant speed. But the images are only refreshed inconsistently ranging from 5 times per second all the way down to 0 times per second(taking 2 seconds to do a refresh) Also I have tried using different image formats all with the same results. The formats I've tried include bitmaps, PNGs, and GIFs (GIFs caused a minor problem in Chrome with flicker though) Could it be possible that Firefox is somehow caching my images causing a slight lag? I send these headers though: Pragma-directive: no-cache Cache-directive: no-cache Cache-control: no-cache Pragma: no-cache Expires: 0

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  • Javascript ( jQuery ) Error: SyntaxError: missing ) after argument list

    - by Obmerk Kronen
    I have the simplest function : jQuery(document).ajaxSuccess(function(e, xhr, settings) { var widget_id_base = '099_cf_samurai_widget'; if(settings.data.search('action=save-widget') != -1 && settings.data.search('id_base=' + widget_id_base) != -1) { // alert(\'yay!'\); my_function_chosen_099(); } }); function my_function_chosen_099(){ jQuery(".chzn-select").chosen(); } which works just fine , but When I add the width Parameter like so : function my_function_chosen_k99(){ jQuery(".chzn-select").chosen(width:'95%'); } it gives me an error of: Error: SyntaxError: missing ) after argument list Source File: http://localhost/my-path/js/o99.chosen.init.js?ver=k99 Line: 20, Column: 41 Source Code: jQuery(".chzn-select").chosen(width:"95%"); .............................................| I have tried escaping: jQuery(".chzn-select").chosen(width:\"95%"\); and even double jQuery(".chzn-select").chosen(width:\\"95%"\\); and in my desperation, even jQuery(".chzn-select").chosen( width:"95%" ); I checked and rechecked the closing of brackets , and also tried with single quotes ' - but nothing . There appear to be a lot of similar questions here , but all I saw was escaping problems, ANd I have tried all that I know .. What is wrong here ?? I assume it is not a simple syntax error - or is it ? ( one which I can not find .. )

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  • Regex to GENERATE thumbnails!?!?! (but that's crazy!)

    - by CryptoMonkey
    Hello everyone! So here is my situation, and the solution that I've come up with to solve the problem. I have created an application that includes TinyMCE to allow users to create HTML content for publishing. The user can include images in their markup, and drag/resize those images effecting the final Width/Height attributes in the IMG tag. This is all great, the users can include images and resize/relocate them to their desired appearance. But one big problem is that I am now sending a (possibly) much larger image to the client, only to have the browser resize the image into the requested Width/Height attributes. All that bandwidth and lost load time.... So my solution is to pre-process my users markup content, scanning all of the IMG tags and parsing out the Height/Width/Src attributes. Then set each img's SRC tag to a phpThumb request with the parsed Height/Width passed into the thumbnails URL. This will create my reduced size image (optimising bandwidth at the expense of CPU and caching). What do you think about this solution? I've seen other posts where people were using mod_rewrite to do something similar, but I want to effect the content on the page service and not manipulate the image requests as they're being received. .... Any thoughts about this design? I need some help with the fine details as my regex skills need some work, but I'm very short on time and promise to pay my technical knowledge debt soon. To make the regex's easier, I can be sure of some things. Only img tags that need this processing will have an existing width="" height="" attributes (with the double quotes, and lower cased text, but I suppose matching the text case insensitive would be better if TinyMCE changes) So a regex to match only the necessary Img tags, and maybe another three regex's to extract the src, the width, and the height? Thanks everyone.

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  • ReplaceAll not working as expected

    - by Tim Kemp
    Still early days with Mathematica so please forgive what is probably a very obvious question. I am trying to generate some parametric plots. I have: ParametricPlot[{ (a + b) Cos[t] - h Cos[(a + b)/b t], (a + b) Sin[t] - h Sin[(a + b)/b t]}, {t, 0, 2 \[Pi]}, PlotRange -> All] /. {a -> 2, b -> 1, h -> 1} No joy: the replacement rules are not applied and a, b and h remain undefined. If I instead do: Hold@ParametricPlot[{ (a + b) Cos[t] - h Cos[(a + b)/b t], (a + b) Sin[t] - h Sin[(a + b)/b t]}, {t, 0, 2 \[Pi]}, PlotRange -> All] /. {a -> 2, b -> 1, h -> 1} it looks like the rules ARE working, as confirmed by the output: Hold[ParametricPlot[{(2 + 1) Cos[t] - 1 Cos[(2 + 1) t], (2 + 1) Sin[t] - 1 Sin[(2 + 1) t]}, {t, 0, 2 \[Pi]}, PlotRange -> All]] Which is what I'd expect. Take the Hold off, though, and the ParametricPlot doesn't work. There's nothing wrong with the equations or the ParametricPlot itself, though, because I tried setting values for a, b and h in a separate expression (a=2; b=1; h=1) and I get my pretty double cardoid out as expected. So, what am I doing wrong with ReplaceAll and why are the transformation rules not working? This is another fundamentally important aspect of MMA that my OOP-ruined brain isn't understanding. I tried reading up on ReplaceAll and ParametricPlot and the closest clue I found was that "ParametricPlot has attribute HoldAll and evaluates f only after assigning specific numerical values to variables" which didn't help much or I wouldn't be here. Thanks.

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  • Dimensions of a collection, and how to traverse it in an efficient, elegant manner

    - by Bruce Ferguson
    I'm trying to find an elegant way to deal with multi-dimensional collections in Scala. My understanding is that I can have up to a 5 dimensional collection using tabulate, such as in the case of the following 2-Dimensional array: val test = Array.tabulate[Double](row,col)(_+_) and that I can access the elements of the array using for(i<-0 until row) { for(j<-0 until col) { test(i)(j) = 0.0 } } If I don't know a priori what I'm going to be handling, what might be a succinct way of determining the structure of the collection, and spanning it, without doing something like: case(Array(x)) => for(i<-1 until dim1) { test(i) = 0.0 } case(Array(x,y)) => for(i<-1 until dim1) { for(j<-1 until dim2) { test(i)(j) = 0.0 } } case(Array(x,y,z)) => ... The dimensional values n1, n2, n3, etc... are private, right? Also, would one use the same trick of unwrapping a 2-D array into a 1-D vector when dealing with n-Dimensional objects if I want a single case to handle the traversal? Thanks in advance Bruce

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  • write a program that prompts the user to input five decimal numbers

    - by user312309
    This is the question. write a program that prompts the user to input five decimal numbers. the program should then add the five decimal numbers, convert the sum to the nearest integer,m and print the result. This is what I've gotten so far: // p111n9.cpp : Defines the entry point for the console application. // #include <iostream> using namespace std; double a, b , c , d , e, f; int main(int argc, char* argv[]) { cout << "enter 5 decimals: " << endl; cin >> a >> b >> c >> d >> e; f = a + b + c + d + e; return 0; } Now I just need to convert the sum(f) to the nearest integer, m and print the result. How do I do this?

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  • Android AutocompleteView OnClickListener

    - by Chirag_RB
    I have 2 Auto Complete Views which i have to pre-populate with some text .However as soon as user clicks on the views , the text should disappear and allow user to enter text . I have written two separate on click listeners to do so . The On click listener for the first one is working fine . However i have to double click for the On click listener of the second one to work. Please find the chunk of code below and come up with some solution . final AutoCompleteTextView source = (AutoCompleteTextView) findViewById(R.id.source); ArrayAdapter source_adapter = new ArrayAdapter(this, R.layout.list_item, Model.City); source.setAdapter(source_adapter); source.setOnClickListener(new OnClickListener(){ public void onClick(View v) { source.setText(""); source.setTextSize(14); } }); final AutoCompleteTextView destination = (AutoCompleteTextView) findViewById(R.id.destination); ArrayAdapter destination_adapter = new ArrayAdapter(this, R.layout.list_item, Model.City); destination.setAdapter(destination_adapter); destination.setOnClickListener(new OnClickListener(){ public void onClick(View v) { destination.setText(""); destination.setTextSize(14); } });

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  • C++ Type error with Object versus Object reference

    - by muddybruin
    I have the following function (which worked in Visual Studio): bool Plane::contains(Vector& point){ return normalVector.dotProduct(point - position) < -doubleResolution; } When I compile it using g++ version 4.1.2 , I get the following error: Plane.cpp: In member function âvirtual bool Plane::contains(Vector&)â: Plane.cpp:36: error: no matching function for call to âVector::dotProduct(Vector)â Vector.h:19: note: candidates are: double Vector::dotProduct(Vector&) So as you can see, the compiler thinks (point-position) is a Vector but it's expecting Vector&. What's the best way to fix this? I verified that this works: Vector temp = point-position; return normalVector.dotProduct(temp) < -doubleResolution; But I was hoping for something a little bit cleaner. I heard a suggestion that adding a copy constructor might help. So I added a copy constructor to Vector (see below), but it didn't help. Vector.h: Vector(const Vector& other); Vector.cpp: Vector::Vector(const Vector& other) :x(other.x), y(other.y), z(other.z), homogenous(other.homogenous) { }

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