Search Results

Search found 37088 results on 1484 pages for 'object element'.

Page 568/1484 | < Previous Page | 564 565 566 567 568 569 570 571 572 573 574 575  | Next Page >

  • JQuery set img src depending on where you click

    - by Anna
    Hello ! I used javascript for loading a picture on my website depending on which "small" photos in ul you clicked... I had something like that : <script type="text/javascript"> function viewImage(src, legende) { document.getElementById("imageBig").src = "images/photos/"+src; document.getElementById("legend").innerHTML = legende; } </script> and in html simply : things like that : <li><a href="#centre" onclick="javascript:viewImage('flute.jpg','La Reine de la Nuit au Comedia')"><img src="images/photos/carre-09.jpg" alt="" /></a> <a href="#centre" onclick="javascript:viewImage('perichole.jpg','Manuelita - <em>La P&eacute;richole</em> &agrave; l&#8217;Op&eacute;ra Comique')"><img src="images/photos/carre-03.jpg" alt="" /></a></li> <li><a href="#centre" onclick="javascript:viewImage('12.png','R&eacute;cital &agrave; Carnac, septembre 2008')"><img src="images/photos/carre-12.jpg" alt="Marion Baglan Carnac R&eacute;" /></a> <a href="#centre" onclick="javascript:viewImage('01.jpg','')"><img src="images/photos/carre-01.jpg" alt="" /></a></li> so you see, I could, depending on which small photos in the unordered list you clicked, load some particular photos, by passing the src string in argument... but I decided to use Jquery to get some fade-in effect. But I can't find a way to pass an argument that would tell my JQuery function which photo to load depending on where I clicked... stuck here : $(document).ready(function(){ $('#ulPhotos').click(function() { var newSrc= $('#imageBig').attr("src", "images/photos/11.jpg"); }); }); I don't want the 11.jpg to be hardcoded, I need to pass it through argument when I click on a special li element in my ul element of id #ulPhotos... I hope I'm clear enough sorry !

    Read the article

  • Ternary operator

    - by Antoine Leclair
    In PHP, I often use the ternary operator to add an attribute to an html element if it applies to the element in question. For example: <select name="blah"> <option value="1"<?= $blah == 1 ? ' selected="selected"' : '' ?>> One </option> <option value="2"<?= $blah == 2 ? ' selected="selected"' : '' ?>> Two </option> </select> I'm starting a project with Pylons using Mako for the templating. How can I achieve something similar? Right now, I see two possibilities that are not ideal. Solution 1: <select name="blah"> % if blah == 1: <option value="1" selected="selected">One</option> % else: <option value="1">One</option> % endif % if blah == 2: <option value="2" selected="selected">Two</option> % else: <option value="2">Two</option> % endif </select> Solution 2: <select name="blah"> <option value="1" % if blah == 1: selected="selected" % endif >One</option> <option value="2" % if blah == 2: selected="selected" % endif >Two</option> </select> In this particular case, the value is equal to the variable tested (value="1" = blah == 1), but I use the same pattern in other situations, like <?= isset($variable) ? ' value="$variable" : '' ?>. I am looking for a clean way to achieve this using Mako.

    Read the article

  • Constructor and Destructors in C++ [Not a question] [closed]

    - by Jack
    I am using gcc. Please tell me if I am wrong - Lets say I have two classes A & B class A { public: A(){cout<<"A constructor"<<endl;} ~A(){cout<<"A destructor"<<endl;} }; class B:public A { public: B(){cout<<"B constructor"<<endl;} ~B(){cout<<"B destructor"<<endl;} }; 1) The first line in B's constructor should be a call to A's constructor ( I assume compiler automatically inserts it). Also the last line in B's destructor will be a call to A's destructor (compiler does it again). Why was it built this way? 2) When I say A * a = new B(); compiler creates a new B object and checks to see if A is a base class of B and if it is it allows 'a' to point to the newly created object. I guess that is why we don't need any virtual constructors. ( with help from @Tyler McHenry , @Konrad Rudolph) 3) When I write delete a compiler sees that a is an object of type A so it calls A's destructor leading to a problem which is solved by making A's destructor virtual. As user - Little Bobby Tables pointed out to me all destructors have the same name destroy() in memory so we can implement virtual destructors and now the call is made to B's destructor and all is well in C++ land. Please comment.

    Read the article

  • Rails rake test returns an error message

    - by eakkas
    I am a rails newbie and receive the following message when I run rake test. This is a an application based on rails community engine. I tried creating a test application just to make sure that my gems etc. are fine and I am able to run rake test successfully in that application. It would be great if someone could shed a light on what is going wrong... /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/whiny_nil.rb:52:in `method_missing': undefined method `merge' for nil:NilClass (NoMethodError) from /home/eakkas/NetBeansProjects/hello_ce/vendor/plugins/community_engine/app/controllers/users_controller.rb:17 from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require' from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:158:in `require_without_desert' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:8:in `require' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:32:in `__each_matching_file' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:7:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:265:in `require_or_load' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:27:in `depend_on' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:26:in `each' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:26:in `depend_on' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:136:in `require_dependency' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:414:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:413:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:413:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:411:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:411:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:197:in `process' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:113:in `send' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:113:in `run'

    Read the article

  • Put together tiles in android sdk and use as background

    - by Jon
    In a feeble attempt to learn some Android development am I stuck at graphics. My aim here is pretty simple: Take n small images and build a random image, larger than the screen with possibility to scroll around. Have an animated object move around on it I have looked at the SDK examples, Lunar Lander especially but there are a few things I utterly fail to wrap my head around. I've got a birds view plan (which in my head seems reasonably sane): How do I merge the tiles into one large image? The background is static so I figure I should do like this: Make a 2d array with refs to the tiles Make a large Drawable and draw the tiles on it At init draw this big image as the background At each onDraw redraw the background of the previous spot of the moving object, and the moving object at its new location The problem is the hands on things. I load the small images with "Bitmap img1 = BitmapFactory.decodeResource (res, R.drawable.img1)", but then what? Should I make a canvas and draw the images on it with "canvas.drawBitmap (img1, x, y, null);"? If so how to get a Drawable/Bitmap from that? I'm totally lost here, and would really appreciate some hands on help (I would of course be grateful for general hints as well, but I'm primarily trying to understand the Graphics objects). To make you, dear reader, see my level of confusion will I add my last desperate try: Drawable drawable; Canvas canvas = new Canvas (); Bitmap img1 = BitmapFactory.decodeResource (res, R.drawable.img1); // 50 x 100 px image Bitmap img2 = BitmapFactory.decodeResource (res, R.drawable.img2); // 50 x 100 px image canvas.drawBitmap (img1, 0, 0, null); canvas.drawBitmap (img2, 50, 0, null); drawable.draw (canvas); // obviously wrong as draw == null this.setBackground (drawable); Thanks in advance

    Read the article

  • __toString magic and type coercion

    - by TomcatExodus
    I've created a Template class for managing views and their associated data. It implements Iterator and ArrayAccess, and permits "sub-templates" for easy usage like so: <p><?php echo $template['foo']; ?></p> <?php foreach($template->post as $post): ?> <p><?php echo $post['bar']; ?></p> <?php endforeach; ?> Anyways, rather than using inline core functions, such as hash() or date(), I figured it would be useful to create a class called TemplateData, which would act as a wrapper for any data stored in the templates. This way, I can add a list of common methods for formatting, for example: echo $template['foo']->asCase('upper'); echo $template['bar']->asDate('H:i:s'); //etc.. When a value is set via $template['foo'] = 'bar'; in the controllers, the value of 'bar' is stored in it's own TemplateData object. I've used the magic __toString() so when you echo a TemplateData object, it casts to (string) and dumps it's value. However, despite the mantra controllers and views should not modify data, whenever I do something like this: $template['foo'] = 1; echo $template['foo'] + 1; //exception It dies on a Object of class TemplateData could not be converted to int; Unless I recast $template['foo'] to a string: echo ((string) $template['foo']) + 1; //outputs 2 Sort of defeats the purpose having to jump through that hoop. Are there any workarounds for this sort of behavior that exist, or should I just take this as it is, an incidental prevention of data modification in views?

    Read the article

  • How to Load external Div that has a dynamic content using ajax and jsp/servlets ?

    - by A.S al-shammari
    I need to use ajax feature to load external div element ( external jsp file) into the current page. That JSP page contains a dynamic content - e.g. content that is based on values received from the current session. I solved this problem , but I'm in doubt because I think that my solution is bad , or maybe there is better solution since I'm not expert. I have three files: Javascript function that is triggered when a element is clicked, it requests html data from a servlet: $("#inboxtable tbody tr").click(function(){ var trID = $(this).attr('id'); $.post("event?view=read",{id:trID}, function(data){ $("#eventContent").html(data); // load external file },"html"); // type }); The servlet "event" loads the data and generates HTML content using include method : String id = request.getParameter("id"); if (id != null) { v.add("Test"); v.add(id); session.setAttribute("readMessageVector", v); request.getRequestDispatcher("readMessage.jsp").include(request, response); } The readMessage jsp file looks like this: <p> Text: ${readMessageVector[0]} </p> <p> ID: ${readMessageVector[1]} </p> My questions Is this solution good enough to solve this problem - loading external jsp that has dynamic content ? Is there better solution ?

    Read the article

  • Any solution to IE8 bug rendering error when hiding elements?

    - by Magnar
    Bug: when hiding an element with JavaScript in IE8, the margin of still-visible other elements on the side is ignored. This bug has been introduced with IE8, since it works as expected in IE6+7 (and other browsers). <html> <head> <style> #a, #b, #c, #d {background: #ccf; padding: 4px; margin-bottom: 8px;} </style> </head> <body> <div id="a">a</div> <div id="b">b</div> <div id="c">c</div> <div id="d">d</div> <script> setTimeout(function () { document.getElementById("b").style.display = "none"; }, 1000); </script> </body> </html> When running this code, notice how a and c have a margin of 8 between them in normal browsers, but a margin of 0 in IE8. Remove the padding, and IE8 behaves like normal. Remove the timeout and IE8 behaves like normal. A border behaves the same way. I've been working with IE-bugs the last 10 years, but this has me stumped. The solution for now is to wrap the divs, and apply the margin to the outer element and other styles to the inner. But that's reminicent of horrible IE6-workarounds. Any better solutions?

    Read the article

  • Set .aspx page title to that of an Eval

    - by user1860529
    I am trying to use an <%# Eval("name") %> to be the title of my page. I can't seem to figure out any solutions online. I have tried the other StackOverflow question but that did now work either. The page is a bio.aspx and on the site it is displayed as bio.aspx?id=123 so the page title needs to vary depending on the ID. I figured I could just use the Eval("name") but no luck yet. I currently am using JavaScript: window.onload = function() { document.title = '<%# Eval("name") %> | Title Line'; } This works, but it still leaves the title tags empty, and it's kind of spammy. Here is the codebehind: using System; using System.Data; using System.Configuration; using System.Collections; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; public partial class DoctorBio : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { Page.Title = "Your Page Title"; HtmlMeta metaDescription = new HtmlMeta(); metaDescription.Name = "description"; metaDescription.Content = "brief description"; Page.Header.Controls.Add(metaDescription); HtmlMeta metaKeywords = new HtmlMeta(); metaKeywords.Name = "keywords"; metaKeywords.Content = "keywords, keywords"; Page.Header.Controls.Add(metaKeywords); } protected void SetPageTitle(object title) { this.Title = title.ToString(); } protected string ReplaceLineBreaks(object text) { string newText = text as string; if (newText == null) { return string.Empty; } return newText.Replace("\r\n", "<br />"); } }

    Read the article

  • Getting around IBActions limited scope

    - by Septih
    Hello, I have an NSCollectionView and the view is an NSBox with a label and an NSButton. I want a double click or a click of the NSButton to tell the controller to perform an action with the represented object of the NSCollectionViewItem. The Item View is has been subclassed, the code is as follows: #import <Cocoa/Cocoa.h> #import "WizardItem.h" @interface WizardItemView : NSBox { id delegate; IBOutlet NSCollectionViewItem * viewItem; WizardItem * wizardItem; } @property(readwrite,retain) WizardItem * wizardItem; @property(readwrite,retain) id delegate; -(IBAction)start:(id)sender; @end #import "WizardItemView.h" @implementation WizardItemView @synthesize wizardItem, delegate; -(void)awakeFromNib { [self bind:@"wizardItem" toObject:viewItem withKeyPath:@"representedObject" options:nil]; } -(void)mouseDown:(NSEvent *)event { [super mouseDown:event]; if([event clickCount] > 1) { [delegate performAction:[wizardItem action]]; } } -(IBAction)start:(id)sender { [delegate performAction:[wizardItem action]]; } @end The problem I've run into is that as an IBAction, the only things in the scope of -start are the things that have been bound in IB, so delegate and viewItem. This means that I cannot get at the represented object to send it to the delegate. Is there a way around this limited scope or a better way or getting hold of the represented object? Thanks.

    Read the article

  • Stack Overflow problem transforming with a custom xslt

    - by Flynn1179
    I've got a system that allows the user the option of providing their own XSLT to apply to some data that's been retrieved, as a means of specifying how that data should be presented. However, if the user includes code in the XSLT equivalent to: <xsl:template match="/"> <xsl:element name="data"> <xsl:apply-templates select="." /> </xsl:element> </xsl:template> this causes .NET to infinitely recurse trying to process it, and produces a stack overflow error. I need to be able to trap this before it crashes the app, as the data that's been retrieved is occasionally quite time-consuming to obtain, and the data is lost when this happens. Is there any way of doing this? I know it's theoretically possible to identify any occurrences of xsl:apply-templates with "." in the select attribute, but this isn't the only way an infinite recursion could happen, I need a way of generically trapping it.

    Read the article

  • Implementation of delegates in C#

    - by Ram
    Hi, I am trying to learn on how to use delegates efficiently in C# and I was just wondering if anyone can guide me through... The following is a sample implementation using delegates... All I am doing is just passing a value through a delegate from one class to another... Please tell me if this is the right way to implement... And also your suggestions... Also, please note that I have de-registered the delegate in : void FrmSample_FormClosing(object sender, FormClosingEventArgs e) { sampleObj.AssignValue -= new Sample.AssignValueDelegate(AssignValue); } Is this de-registration necessary? The following is the code that I have written.. public partial class FrmSample : Form { Sample sampleObj; public FrmSample() { InitializeComponent(); this.Load += new EventHandler(FrmSample_Load); this.FormClosing += new FormClosingEventHandler(FrmSample_FormClosing); sampleObj = new Sample(); sampleObj.AssignValue = new Sample.AssignValueDelegate(AssignValue); } void FrmSample_FormClosing(object sender, FormClosingEventArgs e) { sampleObj.AssignValue -= new Sample.AssignValueDelegate(AssignValue); } void FrmSample_Load(object sender, EventArgs e) { sampleObj.LoadValue(); } void AssignValue(string value) { MessageBox.Show(value); } } class Sample { public delegate void AssignValueDelegate(string value); public AssignValueDelegate AssignValue; internal void LoadValue() { if (AssignValue != null) { AssignValue("This is a test message"); } } } Pls provide your feedback on whether this is right... Thanks, Ram

    Read the article

  • Membership.Updateuser not really updating the database.

    - by Shimrod
    Hi everybody, I'm currently working on a membership system for my web application, which is based on forms authentication from the framework. I created some users with the integrated tool, and the login is perfectly working. But now what I want to do is to give administrator the capability to create, modify, delete users. So here is what I've got right now: Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Dim muc As MembershipUserCollection = Membership.GetAllUsers() ComboBox1.DataSource = muc ComboBox1.DataValueField = "UserName" ComboBox1.DataTextField = "UserName" ComboBox1.DataBind() End Sub Protected Sub ComboBox1_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles ComboBox1.SelectedIndexChanged Dim userName As String = ComboBox1.SelectedValue Dim mu As MembershipUser = Membership.GetUser(userName) Dim userRoles As String() = Roles.GetRolesForUser(userName) tbComments.Text = mu.Comment tbEmail.Text = mu.Email lblUserName.Text = mu.UserName End Sub Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click Dim userName As String = ComboBox1.SelectedValue Dim mu As MembershipUser = Membership.GetUser(userName) If Not mu Is Nothing Then Try mu.Comment = tbComments.Text Membership.UpdateUser(mu) mu.Email = tbEmail.Text Membership.UpdateUser(mu) mu.IsApproved = True Membership.UpdateUser(mu) mu = Nothing Catch ex As Exception Console.WriteLine(ex.ToString()) End Try End If DetailPanel.Visible = False End Sub The problem is that the record doesn't seem to be updated in the database. I made the multiple calls to Membership.UpdateUser after reading this blog entry, but it didn't change anything. A strange think I noticed while debugging, is that when I enter the Button1_Click method, Membership.GetUser(userName) returns me values from my precedent attempt ! I don't really understand what I'm missing. Does someone have a clue ? Thanks in advance !

    Read the article

  • Using Mergesort to calculate number of inversions in C++

    - by Brown
    void MergeSort(int A[], int n, int B[], int C[]) { if(n > 1) { Copy(A,0,floor(n/2),B,0,floor(n/2)); Copy(A,floor(n/2),n-1,C,0,floor(n/2)-1); MergeSort(B,floor(n/2),B,C); MergeSort(C,floor(n/2),B,C); Merge(A,B,0,floor(n/2),C,0,floor(n/2)-1); } }; void Copy(int A[], int startIndexA, int endIndexA, int B[], int startIndexB, int endIndexB) { while(startIndexA < endIndexA && startIndexB < endIndexB) { B[startIndexB]=A[startIndexA]; startIndexA++; startIndexB++; } }; void Merge(int A[], int B[],int leftp, int rightp, int C[], int leftq, int rightq) //Here each sub array (B and C) have both left and right indices variables (B is an array with p elements and C is an element with q elements) { int i=0; int j=0; int k=0; while(i < rightp && j < rightq) { if(B[i] <=C[j]) { A[k]=B[i]; i++; } else { A[k]=C[j]; j++; inversions+=(rightp-leftp); //when placing an element from the right array, the number of inversions is the number of elements still in the left sub array. } k++; } if(i=rightp) Copy(A,k,rightp+rightq,C,j,rightq); else Copy(A,k,rightp+rightq,B,i,rightp); } I am specifically confused on the effect of the second 'B' and 'C' arguments in the MergeSort calls. I need them in there so I have access to them for Copy and and Merge, but

    Read the article

  • What's a reasonable way to mutate a primitive variable from an anonymous Java class?

    - by Steve
    I would like to write the following code: boolean found = false; search(new SearchCallback() { @Override void onFound(Object o) { found = true; } }); Obviously this is not allowed, since found needs to be final. I can't make found a member field for thread-safety reasons. What is the best alternative? One workaround is to define final class MutableReference<T> { private T value; MutableReference(T value) { this.value = value; } T get() { return value; } void set(T value) { this.value = value; } } but this ends up taking a lot of space when formatted properly, and I'd rather not reinvent the wheel if at all possible. I could use a List<Boolean> with a single element (either mutating that element, or else emptying the list) or even a Boolean[1]. But everything seems to smell funny, since none of the options are being used as they were intended. What is a reasonable way to do this?

    Read the article

  • How best to associate code with events in jQuery?

    - by Ned Batchelder
    Suppose I have a <select> element on my HTML page, and I want to run some Javascript when the selection is changed. I'm using jQuery. I have two ways to associate the code with the element. Method 1: jQuery .change() <select id='the_select'> <option value='opt1'>One</option> <option value='opt2'>Two</option> </select> <script> $('#the_select').change(function() { alert('Changed!'); }); </script> Method 2: onChange attribute <select id='the_select' onchange='selectChanged();'> <option value='opt1'>One</option> <option value='opt2'>Two</option> </select> <script> function selectChanged() { alert('Changed!'); } </script> I understand the different modularity here: for example, method 1 keeps code references out of the HTML, but method 2 doesn't need to mention HTML ids in the code. What I don't understand is: are there operational differences between these two that would make me prefer one over the other? For example, are there edge-case browsers where one of these works and the other doesn't? Is the integration with jQuery better for either? Does the late-binding of the code to the event make a difference in the behavior of the page? Which do you pick and why?

    Read the article

  • Visual Studio crashes consistently on web-related projects

    - by Traveling Tech Guy
    Hi, I have a brand new VS2010 installed on a Win2008R2 machine. I started getting this error when debugging a WCF service project: "Attempted to read or write protected memory. This is often an indication that other memory is corrupt." When I started developing a web site a week later, this became consistent - I can't debug it. The stack dump reads: at Microsoft.VisualStudio.WebHost.Host.ProcessRequest(Connection conn) at Microsoft.VisualStudio.WebHost.Server.OnSocketAccept(Object acceptedSocket) at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context(Object state) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx) at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem() at System.Threading.ThreadPoolWorkQueue.Dispatch() at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback() I tried searching online, and some recommend turning off the "Suppress JIT Optimizations" in the Debugging options - this dos not seem to make a difference. Clearly the problem is with the built in web server. But am I doing something wrong? Is there something I can do? Or is this a known bug? Thanks for your time, Guy Update 12/31: Today I tried using CassiniDev as a replacement to the original VS2010 WebServer - exact same result. My suspicion is that there's some internal conflict between VS2010, Windows Server 2008R2 and maybe the fact that it's a 64 bit OS. I switched to using IIS as my debug server - and that seems to work, with some annoying side effects. My conclusion: do not use a 64 bit server system as your dev machine. Develop on 32bit - deploy to 64bit. Side conclusion: there are some scenarios Microsoft's QA doesn't test.

    Read the article

  • Unsort: remembering a permutation and undoing it.

    - by dreeves
    Suppose I have a function f that takes a vector v and returns a new vector with the elements transformed in some way. It does that by calling function g that assumes the vector is sorted. So I want f to be defined like so: f[v_] := Module[{s, r}, s = Sort[v]; (* remember the permutation applied in order to sort v *) r = g[s]; Unsort[r] (* apply the inverse of that permutation *) ] What's the best way to do the "Unsort"? Or could we get really fancy and have this somehow work: answer = Unsort[g[Sort[v]]]; ADDED: Let's make this concrete with a toy example. Suppose we want a function f that takes a vector and transforms it by adding to each element the next smallest element, if any. That's easy to write if we assume the vector is sorted, so let's write a helper function g that makes that assumption: g[v_] := v + Prepend[Most@v, 0] Now for the function we really want, f, that works whether or not v is sorted: f[v_] := (* remember the order; sort it; call g on it; put it back in the original order; return it *)

    Read the article

  • Implementing list position locator in C++?

    - by jfrazier
    I am writing a basic Graph API in C++ (I know libraries already exist, but I am doing it for the practice/experience). The structure is basically that of an adjacency list representation. So there are Vertex objects and Edge objects, and the Graph class contains: list<Vertex *> vertexList list<Edge *> edgeList Each Edge object has two Vertex* members representing its endpoints, and each Vertex object has a list of Edge* members representing the edges incident to the Vertex. All this is quite standard, but here is my problem. I want to be able to implement deletion of Edges and Vertices in constant time, so for example each Vertex object should have a Locator member that points to the position of its Vertex* in the vertexList. The way I first implemented this was by saving a list::iterator, as follows: vertexList.push_back(v); v->locator = --vertexList.end(); Then if I need to delete this vertex later, then rather than searching the whole vertexList for its pointer, I can call: vertexList.erase(v->locator); This works fine at first, but it seems that if enough changes (deletions) are made to the list, the iterators will become out-of-date and I get all sorts of iterator errors at runtime. This seems strange for a linked list, because it doesn't seem like you should ever need to re-allocate the remaining members of the list after deletions, but maybe the STL does this to optimize by keeping memory somewhat contiguous? In any case, I would appreciate it if anyone has any insight as to why this happens. Is there a standard way in C++ to implement a locator that will keep track of an element's position in a list without becoming obsolete? Much thanks, Jeff

    Read the article

  • asp.net jquery how to use Plugin/Validation with web content

    - by Eyla
    I have a asp.net web content from that have a asp.net textbox and I want to use Plugin/Validation but it is not working with me here is my code: <%@ Page Title="" Language="C#" MasterPageFile="~/Master.Master" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="IMAM_APPLICATION.WebForm1" %> <%@ Register assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" tagprefix="asp" %> <asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server"> <script src="js/jquery-1.4.1.js" type="text/javascript"></script> <script src="js/jquery.validate.js" type="text/javascript"></script> <script type="text/javascript"> $(document).ready(function() { $.validator.addMethod("#<%=TextBox1.ClientID %>", function(value, element) { return this.optional(element) || /^(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).{8,16}$/i.test(value); }, "Passwords are 8-16 characters with uppercase letters, lowercase letters and at least one number."); }); </script> </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server"> </asp:Content> <asp:Content ID="Content3" ContentPlaceHolderID="ContentPlaceHolder2" runat="server"> <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> </asp:Content>

    Read the article

  • Java downcasting dilemma

    - by Shades88
    please have a look at this code here. class Vehicle { public void printSound() { System.out.print("vehicle"); } } class Car extends Vehicle { public void printSound() { System.out.print("car"); } } class Bike extends Vehicle{ public void printSound() { System.out.print("bike"); } } public class Test { public static void main(String[] args) { Vehicle v = new Car(); Bike b = (Bike)v; v.printSound(); b.printSound(); Object myObj = new String[]{"one", "two", "three"}; for (String s : (String[])myObj) System.out.print(s + "."); } } Executing this code will give ClassCastException saying inheritance.Car cannot be cast to inheritance.Bike. Now look at the line Object myObj = new String[]{"one", "two", "three"};. This line is same as Vehicle v = new Car(); right? In both lines we are assigning sub class object to super class reference variable. But downcasting String[]myObj is allowed but (Bike)v is not. Please help me understand what is going on around here.

    Read the article

  • SQLAlchemy: who is in charge of the "session"? ( and how to unit-test with sessions )

    - by Nick Perkins
    I need some guidance on how to use session objects with SQLAlchemy, and how to organize Unit Tests of my mapped objects. What I would like to able to do is something like this: thing = BigThing() # mapped object child = thing.new_child() # create and return a related object thing.save() # will also save the child object In order to achieve this, I was thinking of having the BigThing actually add itself ( and it's children ) to the database -- but maybe this not a good idea? One reason to add objects as soon as possible is Automatic id values that are assigned by the database -- the sooner they are available, the fewer problems there are ( right? ) What is the best way to manage session objects? Who is in charge of the session? Should it be created only when required? or saved for a long time? What about Unit Tests for my mapped objects?...how should the session be handled? Is it ever OK to have mapped objects just automatically add themselves to a database? or is that going to lead to trouble?

    Read the article

  • Why isn't the Cache invalidated after table update using the SqlCacheDependency?

    - by Jason
    I have been trying to get SqlCacheDependency working. I think I have everything set up correctly, but when I update the table, the item in the Cache isn't invalidated. Can you look at my code and see if I am missing anything? I enabled the Service Broker for the Sandbox database. I have placed the following code in the Global.asax file. I also restart IIS to make sure it is called. void Application_Start(object sender, EventArgs e) { SqlDependency.Start(ConfigurationManager.ConnectionStrings["SandboxConnectionString"].ConnectionString); } I have placed this entry in the web.config file: <system.web> <caching> <sqlCacheDependency enabled="true" pollTime="10000"> <databases> <add name="Sandbox" connectionStringName="SandboxConnectionString"/> </databases> </sqlCacheDependency> </caching> </system.web> I call this code to put the item into the cache: protected void CacheDataSetButton_Click(object sender, EventArgs e) { using (SqlConnection sqlConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["SandboxConnectionString"].ConnectionString)) { using (SqlCommand sqlCommand = new SqlCommand("SELECT PetID, Name, Breed, Age, Sex, Fixed, Microchipped FROM dbo.Pets", sqlConnection)) { using (SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(sqlCommand)) { DataSet petsDataSet = new DataSet(); sqlDataAdapter.Fill(petsDataSet, "Pets"); SqlCacheDependency petsSqlCacheDependency = new SqlCacheDependency(sqlCommand); Cache.Insert("Pets", petsDataSet, petsSqlCacheDependency, DateTime.Now.AddSeconds(10), Cache.NoSlidingExpiration); } } } } Then I bind the GridView with this code: protected void BindGridViewButton_Click(object sender, EventArgs e) { if (Cache["Pets"] != null) { GridView1.DataSource = Cache["Pets"] as DataSet; GridView1.DataBind(); } } Between attempts to DataBind the GridView, I change the table's values expecting it to invalidate the Cache["Pets"] item, but it seems to stay in the Cache indefinitely.

    Read the article

  • Checking instance of non-class constrained type parameter for null in generic method

    - by casperOne
    I currently have a generic method where I want to do some validation on the parameters before working on them. Specifically, if the instance of the type parameter T is a reference type, I want to check to see if it's null and throw an ArgumentNullException if it's null. Something along the lines of: // This can be a method on a generic class, it does not matter. public void DoSomething<T>(T instance) { if (instance == null) throw new ArgumentNullException("instance"); Note, I do not wish to constrain my type parameter using the class constraint. I thought I could use Marc Gravell's answer on "How do I compare a generic type to its default value?", and use the EqualityComparer<T> class like so: static void DoSomething<T>(T instance) { if (EqualityComparer<T>.Default.Equals(instance, null)) throw new ArgumentNullException("instance"); But it gives a very ambiguous error on the call to Equals: Member 'object.Equals(object, object)' cannot be accessed with an instance reference; qualify it with a type name instead How can I check an instance of T against null when T is not constrained on being a value or reference type?

    Read the article

  • Optimizing a bin-placement algorithm

    - by user258651
    Alright, I've got two collections, and I need to place elements from collection1 into the bins (elements) of collection2, based on whether their value falls within a given bin's range. For a concrete example, assume I have a sorted collection objects (bins) which have an int range ([1...4], [5..10], etc). I need to determine the range an int falls in, and place it in the appropriate bin. foreach(element n in collection1) { foreach(bin m in collection2) { if (m.inRange(n)) { m.add(n); break; } } } So the obvious NxM complexity algorithm is there, but I really would like to see Nxlog(M). To do this I'd like to use BinarySearch in place of the inner foreach loop. To use BinarySearch, I need to implement an IComparer class to do the searching for me. The problem I'm running into is this approach would require me to make an IComparer.Compare function that compares two different types of objects (an element to its bin), and that doesn't seem possible or correct. So I'm asking, how should I write this algorithm?

    Read the article

< Previous Page | 564 565 566 567 568 569 570 571 572 573 574 575  | Next Page >