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• How to change UINavigationBar background image - iphone sdk ?

  - by tester

  first of all, i read all "changing uinavigationbar color & backgound image", but i couldnt get over my problem. i have a tabbar app with 4 tabs. each tab has navigationcontroller. (i arranged all the objects in mainwindow.xib file in IB) in thew first tab, i wanna display 1.jpg on navigationbars background image in first view. when the use taps the tableviews row, how can i display "2.jpg" on navigationbar for second view? i also wanna display different images for each tabs. how can i solve it? thanx for all.

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• Parallelism in .NET – Part 16, Creating Tasks via a TaskFactory

  - by Reed

  The Task class in the Task Parallel Library supplies a large set of features.  However, when creating the task, and assigning it to a TaskScheduler, and starting the Task, there are quite a few steps involved.  This gets even more cumbersome when multiple tasks are involved.  Each task must be constructed, duplicating any options required, then started individually, potentially on a specific scheduler.  At first glance, this makes the new Task class seem like more work than ThreadPool.QueueUserWorkItem in .NET 3.5. In order to simplify this process, and make Tasks simple to use in simple cases, without sacrificing their power and flexibility, the Task Parallel Library added a new class: TaskFactory. The TaskFactory class is intended to “Provide support for creating and scheduling Task objects.”  Its entire purpose is to simplify development when working with Task instances.  The Task class provides access to the default TaskFactory via the Task.Factory static property.  By default, TaskFactory uses the default TaskScheduler to schedule tasks on a ThreadPool thread.  By using Task.Factory, we can automatically create and start a task in a single “fire and forget” manner, similar to how we did with ThreadPool.QueueUserWorkItem: Task.Factory.StartNew(() => this.ExecuteBackgroundWork(myData) ); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This provides us with the same level of simplicity we had with ThreadPool.QueueUserWorkItem, but even more power.  For example, we can now easily wait on the task: // Start our task on a background thread var task = Task.Factory.StartNew(() => this.ExecuteBackgroundWork(myData) ); // Do other work on the main thread, // while the task above executes in the background this.ExecuteWorkSynchronously(); // Wait for the background task to finish task.Wait(); TaskFactory simplifies creation and startup of simple background tasks dramatically. In addition to using the default TaskFactory, it’s often useful to construct a custom TaskFactory.  The TaskFactory class includes an entire set of constructors which allow you to specify the default configuration for every Task instance created by that factory.  This is particularly useful when using a custom TaskScheduler.  For example, look at the sample code for starting a task on the UI thread in Part 15: // Given the following, constructed on the UI thread // TaskScheduler uiScheduler = TaskScheduler.FromCurrentSynchronizationContext(); // When inside a background task, we can do string status = GetUpdatedStatus(); (new Task(() => { statusLabel.Text = status; })) .Start(uiScheduler); This is actually quite a bit more complicated than necessary.  When we create the uiScheduler instance, we can use that to construct a TaskFactory that will automatically schedule tasks on the UI thread.  To do that, we’d create the following on our main thread, prior to constructing our background tasks: // Construct a task scheduler from the current SynchronizationContext (UI thread) var uiScheduler = TaskScheduler.FromCurrentSynchronizationContext(); // Construct a new TaskFactory using our UI scheduler var uiTaskFactory = new TaskFactory(uiScheduler); If we do this, when we’re on a background thread, we can use this new TaskFactory to marshal a Task back onto the UI thread.  Our previous code simplifies to: // When inside a background task, we can do string status = GetUpdatedStatus(); // Update our UI uiTaskFactory.StartNew( () => statusLabel.Text = status); Notice how much simpler this becomes!  By taking advantage of the convenience provided by a custom TaskFactory, we can now marshal to set data on the UI thread in a single, clear line of code!

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• iphone - creating a reference to a MPMoviePlayerController

  - by Mike

  At some point in my code I am creating a MPMoviePlayerController object and playing it. As I need to reference this object at some other methods in my code that runs asynchronously, I need to store a pointer to the movie object etc., so I can use that. Declaring MPMoviePlayerController * myMovie on the header file is out of question, because the compiler will give me an error saying "expected specifier-qualifier-list before 'MPMoviePlayerController'". If it was a view I could do something like [self.view viewWithTag:99]; to get the object, but the MPMoviePlayerController does not allow this. How can I obtain the movie object or store a reference to it, so I can call the object in other methods? thanks for any help.

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• Bug with asp.net mvc2, collection and ValidationMessageFor ?

  - by Rafael Mueller

  I'm with a really weird bug with asp.net mvc2 (rtm) and ValidationMessageFor. The example below throws a System.Collections.Generic.KeyNotFoundException on Response.Write(Html.ValidationMessageFor(n = n[index].Name)); Any ideas why thats happening? I'm accessing the same dictionary twice before, but it only throws the error on ValidationMessageFor, any thoughts? Here's the code. public class Parent { public IList<Child> Childrens { get; set; } [Required] public string Name { get; set; } } public class Child { [Required] public string Name { get; set; } } The controller public class ParentController : Controller { public ActionResult Create() { var parent = new Parent { Name = "Parent" }; parent.Childrens = new List<Child> { new Child(), new Child(), new Child() }; return View(parent); } } The view (Create.aspx) <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Parent>" %> <%@ Import Namespace="BugAspNetMVC" %> <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> <%Html.EnableClientValidation(); %> <% using (Html.BeginForm()) {%> <%=Html.LabelFor(p => p.Name)%> <%=Html.TextBoxFor(p => p.Name)%> <%=Html.ValidationMessageFor(p => p.Name)%> <%Html.RenderPartial("Childrens", Model.Childrens); %> <%} %> </asp:Content> And the partial view (Childrens.ascx) <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<IList<Child>>" %> <%@ Import Namespace="BugAspNetMVC"%> <% for (int i = 0; i < Model.Count; i++) { var index = i; Response.Write(Html.LabelFor(n => n[index].Name)); Response.Write(Html.TextBoxFor(n => n[index].Name)); Response.Write(Html.ValidationMessageFor(n => n[index].Name)); } %>

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• Django - How best to handle ValidationErrors after form.save(commit=False)

  - by orokusaki

  This is a fragment of my code from a view: if form.is_valid(): instance = form.save(commit=False) try: instance.account = request.account instance.full_clean() except ValidationError, e: # Do something with the errors here... I don't know what the best thing to do here is, but I certainly don't want to do it 180 times. This is an utter mess. Who would want to handle validation errors manually in every view. If you're not modifying the instance after save(commit=False), you don't have to worry about this, but what about in my case where every model has a foreign key to account which is set behind the scenes and hidden from the user? Any help is really appreciated.

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• Discoverer 11g 11.1.1.2 Certified with EBS 12 on Five New Platforms

  - by Steven Chan

  Oracle Fusion Middleware 11g Release 1 includes Oracle Discoverer.  Discoverer is an ad-hoc query, reporting, analysis, and Web-publishing tool that allows end-users to work directly with Oracle E-Business Suite OLTP data.We certified Discoverer 11gR1 11.1.1.2 with the E-Business Suite Release 11i and 12 on Linux earlier this year.  Our Applications Platforms Group has just released five additional platform certifications for Discoverer 11.1.1.2 for Oracle E-Business Suite Release 12 (12.0.x and 12.1.x).Certified EBS 12 PlatformsLinux x86-64 (Oracle Enterprise Linux 4, 5) Linux x86-64 (RHEL 4, 5) Linux x86-64 (SLES 10) Oracle Solaris on SPARC (64-bit) (Solaris 9, 10) HP-UX Itanium (11.23, 11.31) HP-UX PA-RISC (64-bit) (11.23, 11.31) IBM AIX on Power Systems (64-bit) (5.3, 6.1) Microsoft Windows Server (32-bit) (2003, 2008)

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• Change Default Scrolling Behavior of UITableView Section Header

  - by davidjhinson

  I have a UITableView with two sections. It is a simple table view. I am using viewForHeaderInSection to create custom views for these headers. So far, so good. The default scrolling behavior is that when a section is encountered, the section header stays anchored below the Nav bar, until the next section scrolls into view. My question is this: can I change the default behavior so that the section headers do NOT stay anchored at the top, but rather, scroll under the nav bar with the rest of the section rows? Am I missing something obvious? Thanks.

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• Html.DropDownListFor not behaving as expected ASP.net MVC

  - by rybl

  Hello, I am new to ASP.net MVC and I am having trouble getting dropdown lists to work correctly. I have a strongly typed view that is attempting to use a Html.DropDownListFor as follows: <%=Html.DropDownListFor(Function(model) model.Arrdep, Model.ArrdepOptions)%> I am populating the list with a property in my model as follows: Public ReadOnly Property ArrdepOptions() As List(Of SelectListItem) Get Dim list As New List(Of SelectListItem) Dim arriveListItem As New SelectListItem() Dim departListItem As New SelectListItem() arriveListItem.Text = "Arrive At" arriveListItem.Value = ArriveDepart.Arrive departListItem.Text = "Depart At" departListItem.Value = ArriveDepart.Depart Select Case Me.Arrdep Case ArriveDepart.Arrive : arriveListItem.Selected = True Case Else : departListItem.Selected = True End Select list.Add(departListItem) list.Add(arriveListItem) Return list End Get End Property The Select Case works find and it sets the right SelectListItem as Selected, but when my view renders the dropdown list no matter what is marked as selected the generated HTML does not have anything selected. Am I obviously doing something wrong or missing something, but I can't for the life of me figure out what.

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• Sorting Android ListView

  - by aeoth

  I'm only starting with Android dev, and while the Milestone is a nice device Java is not my natural language and I'm struggling with both the Google docs on Android SDK, Eclipse and Java itself. Anyway... I'm writing a microblog client for Android to go along with my Windows client (MahTweets). At the moment I've got Tweets coming and going without fail, the problem is with the UI. The initial call will order items correctly (as in highest to lowest) 3 2 1 When a refresh is made 3 2 1 6 5 4 After the tweets are processed, I'm calling adapter.notifyDataSetChanged(); Initially I thought that getItem() on the Adapter needed to be sorted (and the code below is what I ended up with), but I'm still not having any luck. public class TweetAdapter extends BaseAdapter { private List<IStatusUpdate> elements; private Context c; public TweetAdapter(Context c, List<IStatusUpdate> Tweets) { this.elements = Tweets; this.c = c; } public int getCount() { return elements.size(); } public Object getItem(int position) { Collections.sort(elements, new IStatusUpdateComparator()); return elements.get(position); } public long getItemId(int id) { return id; } public void Remove(int id) { notifyDataSetChanged(); } public View getView(int position, View convertView, ViewGroup parent) { RelativeLayout rowLayout; IStatusUpdate t = elements.get(position); rowLayout = t.GetParent().GetUI(t, parent, c); return rowLayout; } class IStatusUpdateComparator implements Comparator { public int compare(Object obj1, Object obj2) { IStatusUpdate update1 = (IStatusUpdate)obj1; IStatusUpdate update2 = (IStatusUpdate)obj2; int result = update1.getID().compareTo(update2.getID()); if (result == -1) return 1; else if (result == 1) return 0; return result; } } } Is there a better way to go about sorting ListViews in Android, while still being able to use the LayoutInflater? (rowLayout = t.GetParent().GetUI(t, parent, c) expands the UI to the specific view which the microblog implementation can provide)

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• ASP.NET TextBox TextChanged event not firing in custom EditorPart

  - by Ben Collins

  This is a classic sort of question, I suppose, but it seems that most people are interested in having the textbox cause a postback. I'm not. I just want the event to fire when a postback occurs. I have created a webpart with a custom editorpart. The editorpart renders with a textbox and a button. Clicking the button causes a dialog to open. When the dialog is closed, it sets the value of the textbox via javascript and then does __doPostBack using the ClientID of the editorpart. The postback happens, but the TextChanged event never fires, and I'm not sure if it's a problem with the way __doPostBack is invoked, or if it's because of the way I'm setting up the event handler, or something else. Here's what I think is the relevant portion of the code from the editorpart: protected override void CreateChildControls() { _txtListUrl = new TextBox(); _txtListUrl.ID = "targetSPList"; _txtListUrl.Style.Add(HtmlTextWriterStyle.Width, "60%"); _txtListUrl.ToolTip = "Select List"; _txtListUrl.CssClass = "ms-input"; _txtListUrl.Attributes.Add("readOnly", "true"); _txtListUrl.Attributes.Add("onChange", "__doPostBack('" + this.ClientID + "', '');"); _txtListUrl.Text = this.ListString; _btnListPicker = new HtmlInputButton(); _btnListPicker.Style.Add(HtmlTextWriterStyle.Width, "60%"); _btnListPicker.Attributes.Add("Title", "Select List"); _btnListPicker.ID = "browseListsSmtButton"; _btnListPicker.Attributes.Add("onClick", "mso_launchListSmtPicker()"); _btnListPicker.Value = "Select List"; this.AddConfigurationOption("News List", "Choose the list that serves as the data source.", new Control[] { _txtListUrl, _btnListPicker }); if (this.ShowViewSelection) { _txtListUrl.TextChanged += new EventHandler(_txtListUrl_TextChanged); _ddlViews = new DropDownList(); _ddlViews.ID = "_ddlViews"; this.AddConfigurationOption("View", _ddlViews); } } protected override void OnPreRender(EventArgs e) { ScriptLink.Register(this.Page, "PickerTreeDialog.js", true); string lastSelectedListId = string.Empty; if (!this.WebId.Equals(Guid.Empty) && !this.ListId.Equals(Guid.Empty)) { lastSelectedListId = SPHttpUtility.EcmaScriptStringLiteralEncode( string.Format("SPList:{0}?SPWeb:{1}:", this.ListId.ToString(), this.WebId.ToString())); } string script = "\r\n var lastSelectedListSmtPickerId = '" + lastSelectedListId + "';" + "\r\n function mso_launchListSmtPicker(){" + "\r\n if (!document.getElementById) return;" + "\r\n" + "\r\n var listTextBox = document.getElementById('" + SPHttpUtility.EcmaScriptStringLiteralEncode(_txtListUrl.ClientID) + "');" + "\r\n if (listTextBox == null) return;" + "\r\n" + "\r\n var serverUrl = '" + SPHttpUtility.EcmaScriptStringLiteralEncode(SPContext.Current.Web.ServerRelativeUrl) + "';" + "\r\n" + "\r\n var callback = function(results) {" + "\r\n if (results == null || results[1] == null || results[2] == null) return;" + "\r\n" + "\r\n lastSelectedListSmtPickerId = results[0];" + "\r\n var listUrl = '';" + "\r\n if (listUrl.substring(listUrl.length-1) != '/') listUrl = listUrl + '/';" + "\r\n if (results[1].charAt(0) == '/') results[1] = results[1].substring(1);" + "\r\n listUrl = listUrl + results[1];" + "\r\n if (listUrl.substring(listUrl.length-1) != '/') listUrl = listUrl + '/';" + "\r\n if (results[2].charAt(0) == '/') results[2] = results[2].substring(1);" + "\r\n listUrl = listUrl + results[2];" + "\r\n listTextBox.value = listUrl;" + "\r\n __doPostBack('" + this.ClientID + "','');" + "\r\n }" + "\r\n LaunchPickerTreeDialog('CbqPickerSelectListTitle','CbqPickerSelectListText','websLists','', serverUrl, lastSelectedListSmtPickerId,'','','/_layouts/images/smt_icon.gif','', callback);" + "\r\n }"; this.Page.ClientScript.RegisterClientScriptBlock(typeof(ListPickerEditorPart), "mso_launchListSmtPicker", script, true); if ((!string.IsNullOrEmpty(_txtListUrl.Text) && _ddlViews.Items.Count == 0) || _listSelectionChanged) { _ddlViews.Items.Clear(); if (!string.IsNullOrEmpty(_txtListUrl.Text)) { using (SPWeb web = SPContext.Current.Site.OpenWeb(this.WebId)) { foreach (SPView view in web.Lists[this.ListId].Views) { _ddlViews.Items.Add(new ListItem(view.Title, view.ID.ToString())); } } _ddlViews.Enabled = _ddlViews.Items.Count > 0; } else { _ddlViews.Enabled = false; } } base.OnPreRender(e); } void _txtListUrl_TextChanged(object sender, EventArgs e) { this.SetPropertiesFromChosenListString(_txtListUrl.Text); _listSelectionChanged = true; } Any ideas? Update: I forgot to mention these methods, which are called above: protected virtual void AddConfigurationOption(string title, Control inputControl) { this.AddConfigurationOption(title, null, inputControl); } protected virtual void AddConfigurationOption(string title, string description, Control inputControl) { this.AddConfigurationOption(title, description, new List<Control>(new Control[] { inputControl })); } protected virtual void AddConfigurationOption(string title, string description, IEnumerable<Control> inputControls) { HtmlGenericControl divSectionHead = new HtmlGenericControl("div"); divSectionHead.Attributes.Add("class", "UserSectionHead"); this.Controls.Add(divSectionHead); HtmlGenericControl labTitle = new HtmlGenericControl("label"); labTitle.InnerHtml = HttpUtility.HtmlEncode(title); divSectionHead.Controls.Add(labTitle); HtmlGenericControl divUserSectionBody = new HtmlGenericControl("div"); divUserSectionBody.Attributes.Add("class", "UserSectionBody"); this.Controls.Add(divUserSectionBody); HtmlGenericControl divUserControlGroup = new HtmlGenericControl("div"); divUserControlGroup.Attributes.Add("class", "UserControlGroup"); divUserSectionBody.Controls.Add(divUserControlGroup); if (!string.IsNullOrEmpty(description)) { HtmlGenericControl spnDescription = new HtmlGenericControl("div"); spnDescription.InnerHtml = HttpUtility.HtmlEncode(description); divUserControlGroup.Controls.Add(spnDescription); } foreach (Control inputControl in inputControls) { divUserControlGroup.Controls.Add(inputControl); } this.Controls.Add(divUserControlGroup); HtmlGenericControl divUserDottedLine = new HtmlGenericControl("div"); divUserDottedLine.Attributes.Add("class", "UserDottedLine"); divUserDottedLine.Style.Add(HtmlTextWriterStyle.Width, "100%"); this.Controls.Add(divUserDottedLine); }

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• Silverlight DataStateBehavior, initial value not used

  - by JimmySavile

  Hi, I am trying to use the Silverlight DataStateBehavior, it works fine in most cases where I click a button which sets say a 'Selected' Property in the view model to either false or true. The DataStateBehavior then tells the VisualStateManager to go to the relevant state. Like this: <Button...> <i:Interaction.Behaviors> <id:DataStateBehavior Binding="{Binding Selected}" Value="True" TrueState="SelectedVisualState" FalseState="DeselectedVisualState"/> </i:Interaction.Behaviors> </Button> The above works fine. What I am trying to do though is to get it to set the correct state when the application loads, if I were to set the 'Selected' property on the view model to true by default I wouldn't see any changes in the UI until I clicked the button to change the viewmodel property. I know there are several classes involved with the DataState stuff including: BindingListener.cs ConverterHelper.cs DataStateBehavior.cs DataStateSwitchBehavior.cs DataTrigger.cs Any clues would be good, Thanks

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• Page navigation in silverlight 4 using MVVM pattern

  - by Archie

  Hello, I have a a navigation application developed in Silverlight 4. It has a main page which contains a frame. I load a particualr view in that frame and I know that I can use NavigationService to navigate to other page which would be loaded in the same frame. But my question is how it can be done using MVVM? To get the frame do I need to pass the reference of the page? Also, as per my knowledge one view is not aware of any other views. So what is the best way to make them aware of each other? I have heard of Controller and Mediator but how shall I implement them so as to get the Frame of the mainpage? It would be very helpful if anyone can give me the example or probably sample code for this. Thanks in advance.

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• A Taxonomy of Numerical Methods v1

  - by JoshReuben

  Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms     Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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• Ubuntu 10.10 Mouse and Keyboard Freeze

  - by Kev

  I installed Ubuntu 10.10 today and have had mouse problem since. Symptoms: At some arbitrary point in time (frequency: 2-3 times per hour), the mouse and keyboard stops working for ever(may be). I start System monitor, I found out network was shutdown just before mouse freeze. Some time my keyboard keep typing one key. For example:77777777777777777777777777777777777777777777777777777.....(it keep typing for 20 sec) I found out a script just solve the freeze problem:(I hit Powerbutton) -----------------/etc/acpi/powerbtn.sh------------------------ event=button[ /]power action=/usr/sbin/fix_mouse.sh -----------------/usr/sbin/fix_mouse.sh------------------------ rmmod psmouse modprobe psmouse Yesterday I install Ubuntu 10.04 FAILED also have mouse problem. When I switch back to Windows XP. The network card is down. It kept connecting and disconnecting 1 time per sec. CPU: i5 Motherboard: ASUS P7P55D OS: Windows XP + Ubuntu 10.10 Video Card: ATI 5770 Mouse,Keyboard: PS/2

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• UiSplitViewController doesn't autorotate.

  - by Michael

  Hello, I have recently run into a problem. My iPad app is somehow preventing the iPad from auto-rotating. My app loads a UISplitView with both of the view controllers returning YES for shouldAutorotateToInterfaceOrientation:. I have set up my info.plist to include the "Supported interface orientations" key with all four orientations. When I run the app, however, rotating the device does not rotate the splitView (even though I am receiving UIDeviceOrientationDidChangeNotification). In addition, when I exit my app in a different orientation that it started in the iPad home screen doesn't autorotate to the correct view until I rotate it again without my app running.... Any Ideas would be much appreciated....

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• ASP.NET MVC Checkbox Group

  - by Greg Ogle

  I am trying to formulate a work-around for the lack of a "checkbox group" in ASP.NET MVC. The typical way to implement this is to have check boxes of the same name, each with the value it represents. <input type="checkbox" name="n" value=1 /> <input type="checkbox" name="n" value=2 /> <input type="checkbox" name="n" value=3 /> When submitted, it will comma delimit all values to the request item "n".. so Request["n"] == "1,2,3" if all three are checked when submitted. In ASP.NET MVC, you can have a parameter of n as an array to accept this post. public ActionResult ActionName( int[] n ) { ... } All of the above works fine. The problem I have is that when validation fails, the check boxes are not restored to their checked state. Any suggestions. Problem Code: (I started with the default asp.net mvc project) Controller public class HomeController : Controller { public ActionResult Index() { var t = getTestModel("First"); return View(t); } [AcceptVerbs(HttpVerbs.Post)] public ActionResult Index(TestModelView t) { if(String.IsNullOrEmpty( t.TextBoxValue)) ModelState.AddModelError("TextBoxValue", "TextBoxValue required."); var newView = getTestModel("Next"); return View(newView); } private TestModelView getTestModel(string prefix) { var t = new TestModelView(); t.Checkboxes = new List<CheckboxInfo>() { new CheckboxInfo(){Text = prefix + "1", Value="1", IsChecked=false}, new CheckboxInfo(){Text = prefix + "2", Value="2", IsChecked=false} }; return t; } } public class TestModelView { public string TextBoxValue { get; set; } public List<CheckboxInfo> Checkboxes { get; set; } } public class CheckboxInfo { public string Text { get; set; } public string Value { get; set; } public bool IsChecked { get; set; } } } ASPX <% using( Html.BeginForm() ){ %> <p><%= Html.ValidationSummary() %></p> <p><%= Html.TextBox("TextBoxValue")%></p> <p><% int i = 0; foreach (var cb in Model.Checkboxes) { %> <input type="checkbox" name="Checkboxes[<%=i%>]" value="<%= Html.Encode(cb.Value) %>" <%=cb.IsChecked ? "checked=\"checked\"" : String.Empty %> /><%= Html.Encode(cb.Text)%><br /> <% i++; } %></p> <p><input type="submit" value="submit" /></p> <% } %> Working Code Controller [AcceptVerbs(HttpVerbs.Post)] public ActionResult Index(TestModelView t) { if(String.IsNullOrEmpty( t.TextBoxValue)) { ModelState.AddModelError("TextBoxValue", "TextBoxValue required."); return View(t); } var newView = getTestModel("Next"); return View(newView); } ASPX int i = 0; foreach (var cb in Model.Checkboxes) { %> <input type="checkbox" name="Checkboxes[<%=i%>].IsChecked" <%=cb.IsChecked ? "checked=\"checked\"" : String.Empty %> value="true" /> <input type="hidden" name="Checkboxes[<%=i%>].IsChecked" value="false" /> <input type="hidden" name="Checkboxes[<%=i%>].Value" value="<%= cb.Value %>" /> <input type="hidden" name="Checkboxes[<%=i%>].Text" value="<%= cb.Text %>" /> <%= Html.Encode(cb.Text)%><br /> <% i++; } %></p> <p><input type="submit" value="submit" /></p> Of course something similar could be done with Html Helpers, but this works.

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• Dell Latitude E6520 overheating

  - by Wu Yi Han

  I'm a newcomer to Ubuntu 11.10. My laptop is a Dell Latitude E6520, Sandy Bridge platform. The system cooling fan is crazy all the time. I don't do any intensive tasks. I really hope my laptop doesn't become a mushroom cloud. I suppose there's no perfect way to solve this... Can I lower the CPU frequency? Jupiter 0.0.51 was installed (power save mode). Cooling worked in my Windows 7 system until I deleted it. (I won't go back to Windows 7.)

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• trying to convert rails 2.3.4 app to rails 3 but views not appearing

  - by kgrad

  I have a simple rails 2.3.4 application I am trying to get running with rails 3.0.0-beta2. I have the server running and all my links and navigation showing, however for some reason the content of my views is not displaying. When I navigate to Site/index the html in my index.html.erb in my site view is completely ignored. There are no errors in the server log. My template is rendered properly (where all the links and navigation are being created) within application.html.erb however all of my actual view files are being ignored. Has anyone experienced this? I am using old style routing with map.connect, could this be the issue? Does anyone have a tutorial on how to convert old routes to new ones? I couldn't figure it out. my current routes look like this: map.connect ':controller/:action/:id' map.connect ':controller/:action/:id.:format' map.root :controller => :site, :action => :index

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• Adding a NavigationBar to UITableViewController programmatically?

  - by Tony

  I am trying to create a uitableviewcontroller as a modal viewcontroller to edit some settings. I am creating the tableviewcontroller in code and the thing i am struggling with currently is how to correctly add a navigation bar to the controller which will have a "Done" button on it that: a) doesnt appear on top of the tableview and b) does not scroll with the tableview?? This happens when i add the navbar to the contoller with: [self.view addSubview:navigationBar]; This adds a navbar to the controller which goes on top and obscures the tables first row and also scrolls with the view? I also thought about simply using a uiviewcontroller with a separate tableview however i like the funcitonality of automatically scrolling the tableview when editing a textfield that the tableviewcontroller gives you. Just cant figure how to setup this navbar?? thx

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• Diagnose PC Hardware Problems with an Ubuntu Live CD

  - by Trevor Bekolay

  So your PC randomly shuts down or gives you the blue screen of death, but you can’t figure out what’s wrong. The problem could be bad memory or hardware related, and thankfully the Ubuntu Live CD has some tools to help you figure it out. Test your RAM with memtest86+ RAM problems are difficult to diagnose—they can range from annoying program crashes, or crippling reboot loops. Even if you’re not having problems, when you install new RAM it’s a good idea to thoroughly test it. The Ubuntu Live CD includes a tool called Memtest86+ that will do just that—test your computer’s RAM! Unlike many of the Live CD tools that we’ve looked at so far, Memtest86+ has to be run outside of a graphical Ubuntu session. Fortunately, it only takes a few keystrokes. Note: If you used UNetbootin to create an Ubuntu flash drive, then memtest86+ will not be available. We recommend using the Universal USB Installer from Pendrivelinux instead (persistence is possible with Universal USB Installer, but not mandatory). Boot up your computer with a Ubuntu Live CD or USB drive. You will be greeted with this screen: Use the down arrow key to select the Test memory option and hit Enter. Memtest86+ will immediately start testing your RAM. If you suspect that a certain part of memory is the problem, you can select certain portions of memory by pressing “c” and changing that option. You can also select specific tests to run. However, the default settings of Memtest86+ will exhaustively test your memory, so we recommend leaving the settings alone. Memtest86+ will run a variety of tests that can take some time to complete, so start it running before you go to bed to give it adequate time. Test your CPU with cpuburn Random shutdowns – especially when doing computationally intensive tasks – can be a sign of a faulty CPU, power supply, or cooling system. A utility called cpuburn can help you determine if one of these pieces of hardware is the problem. Note: cpuburn is designed to stress test your computer – it will run it fast and cause the CPU to heat up, which may exacerbate small problems that otherwise would be minor. It is a powerful diagnostic tool, but should be used with caution. Boot up your computer with a Ubuntu Live CD or USB drive, and choose to run Ubuntu from the CD or USB drive. When the desktop environment loads up, open the Synaptic Package Manager by clicking on the System menu in the top-left of the screen, then selecting Administration, and then Synaptic Package Manager. Cpuburn is in the universe repository. To enable the universe repository, click on Settings in the menu at the top, and then Repositories. Add a checkmark in the box labeled “Community-maintained Open Source software (universe)”. Click close. In the main Synaptic window, click the Reload button. After the package list has reloaded and the search index has been rebuilt, enter “cpuburn” in the Quick search text box. Click the checkbox in the left column, and select Mark for Installation. Click the Apply button near the top of the window. As cpuburn installs, it will caution you about the possible dangers of its use. Assuming you wish to take the risk (and if your computer is randomly restarting constantly, it’s probably worth it), open a terminal window by clicking on the Applications menu in the top-left of the screen and then selection Applications > Terminal. Cpuburn includes a number of tools to test different types of CPUs. If your CPU is more than six years old, see the full list; for modern AMD CPUs, use the terminal command burnK7 and for modern Intel processors, use the terminal command burnP6 Our processor is an Intel, so we ran burnP6. Once it started up, it immediately pushed the CPU up to 99.7% total usage, according to the Linux utility “top”. If your computer is having a CPU, power supply, or cooling problem, then your computer is likely to shutdown within ten or fifteen minutes. Because of the strain this program puts on your computer, we don’t recommend leaving it running overnight – if there’s a problem, it should crop up relatively quickly. Cpuburn’s tools, including burnP6, have no interface; once they start running, they will start driving your CPU until you stop them. To stop a program like burnP6, press Ctrl+C in the terminal window that is running the program. Conclusion The Ubuntu Live CD provides two great testing tools to diagnose a tricky computer problem, or to stress test a new computer. While they are advanced tools that should be used with caution, they’re extremely useful and easy enough that anyone can use them. Similar Articles Productive Geek Tips Reset Your Ubuntu Password Easily from the Live CDCreate a Persistent Bootable Ubuntu USB Flash DriveAdding extra Repositories on UbuntuHow to Share folders with your Ubuntu Virtual Machine (guest)Building a New Computer – Part 3: Setting it Up TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Have Fun Editing Photo Editing with Citrify Outlook Connector Upgrade Error Gadfly is a cool Twitter/Silverlight app Enable DreamScene in Windows 7 Microsoft’s “How Do I ?” Videos Home Networks – How do they look like & the problems they cause

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• UINavigationController leak/understanding popViewController

  - by Kamchatka

  Hello, I have a navigation controller and a table view. When someone click on the table view, I do the following: MyViewController *myViewController = [[MyViewController alloc] initWithImage:image]; [image release]; [self.navigationController pushViewController:myViewController animated:YES]; [myViewController release]; myViewController will retain the image. Now, if I go back and forth in the NavigationController, I get a leak because a new MyViewController gets created each time and apparently the popViewController doesn't release the myViewController. My question: Why doesn't popViewController release the controller? How should I handle that? Put the myViewController as a member of my class and check if it already exists instead of creating it each time? Thanks in advance for your help,

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• Visual Studio 2010 Beta start without debugging Console wont stay open

  - by CousinVinny

  I want to keep the console (output) window open to view the output of the project I am working on. I have enabled the start without debugging option and added the button to the debugging toolbar, but alas it fails to keep it open nicely like in visual studio 2008. I have to add cin.getline() etc etc etc to get it to stay open, but I don't want to type it. Any suggestions as to alter it Visual Studio 2010 to keep it open, or any debugging tricks to make it easier to view output for longer than a flash. Visual Studio used to have a "Press any key to continue prompt" I want it back...

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• JBoss5: Cannot deploy due to java.util.zip.ZipException: error in opening zip file

  - by Andreas

  I have a web client and a EJB project, which I created with Eclipse 3.4. When I want to deploy it on Jboss 5.0.1, I receive the error below. I searched a lot but I wasn't able to find a solution to this. 18:21:21,899 INFO [ServerImpl] Starting JBoss (Microcontainer)... 18:21:21,900 INFO [ServerImpl] Release ID: JBoss [Morpheus] 5.0.1.GA (build: SVNTag=JBoss_5_0_1_GA date=200902231221) 18:21:21,900 INFO [ServerImpl] Bootstrap URL: null 18:21:21,900 INFO [ServerImpl] Home Dir: /Applications/jboss-5.0.1.GA 18:21:21,900 INFO [ServerImpl] Home URL: file:/Applications/jboss-5.0.1.GA/ 18:21:21,901 INFO [ServerImpl] Library URL: file:/Applications/jboss-5.0.1.GA/lib/ 18:21:21,901 INFO [ServerImpl] Patch URL: null 18:21:21,901 INFO [ServerImpl] Common Base URL: file:/Applications/jboss-5.0.1.GA/common/ 18:21:21,902 INFO [ServerImpl] Common Library URL: file:/Applications/jboss-5.0.1.GA/common/lib/ 18:21:21,902 INFO [ServerImpl] Server Name: default 18:21:21,902 INFO [ServerImpl] Server Base Dir: /Applications/jboss-5.0.1.GA/server 18:21:21,902 INFO [ServerImpl] Server Base URL: file:/Applications/jboss-5.0.1.GA/server/ 18:21:21,902 INFO [ServerImpl] Server Config URL: file:/Applications/jboss-5.0.1.GA/server/default/conf/ 18:21:21,902 INFO [ServerImpl] Server Home Dir: /Applications/jboss-5.0.1.GA/server/default 18:21:21,902 INFO [ServerImpl] Server Home URL: file:/Applications/jboss-5.0.1.GA/server/default/ 18:21:21,903 INFO [ServerImpl] Server Data Dir: /Applications/jboss-5.0.1.GA/server/default/data 18:21:21,903 INFO [ServerImpl] Server Library URL: file:/Applications/jboss-5.0.1.GA/server/default/lib/ 18:21:21,903 INFO [ServerImpl] Server Log Dir: /Applications/jboss-5.0.1.GA/server/default/log 18:21:21,903 INFO [ServerImpl] Server Native Dir: /Applications/jboss-5.0.1.GA/server/default/tmp/native 18:21:21,903 INFO [ServerImpl] Server Temp Dir: /Applications/jboss-5.0.1.GA/server/default/tmp 18:21:21,903 INFO [ServerImpl] Server Temp Deploy Dir: /Applications/jboss-5.0.1.GA/server/default/tmp/deploy 18:21:22,669 INFO [ServerImpl] Starting Microcontainer, bootstrapURL=file:/Applications/jboss-5.0.1.GA/server/default/conf/bootstrap.xml 18:21:23,535 INFO [VFSCacheFactory] Initializing VFSCache [org.jboss.virtual.plugins.cache.CombinedVFSCache] 18:21:23,541 INFO [VFSCacheFactory] Using VFSCache [CombinedVFSCache[real-cache: null]] 18:21:23,942 INFO [CopyMechanism] VFS temp dir: /Applications/jboss-5.0.1.GA/server/default/tmp 18:21:23,943 INFO [ZipEntryContext] VFS force nested jars copy-mode is enabled. 18:21:26,263 INFO [ServerInfo] Java version: 1.5.0_16,Apple Inc. 18:21:26,264 INFO [ServerInfo] Java Runtime: Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_16-b06-284) 18:21:26,264 INFO [ServerInfo] Java VM: Java HotSpot(TM) Server VM 1.5.0_16-133,Apple Inc. 18:21:26,264 INFO [ServerInfo] OS-System: Mac OS X 10.5.6,i386 18:21:26,336 INFO [JMXKernel] Legacy JMX core initialized 18:21:30,432 INFO [ProfileServiceImpl] Loading profile: default from: org.jboss.system.server.profileservice.repository.SerializableDeploymentRepository@e1d5d9(root=/Applications/jboss-5.0.1.GA/server, key=org.jboss.profileservice.spi.ProfileKey@143b82c3[domain=default,server=default,name=default]) 18:21:30,436 INFO [ProfileImpl] Using repository:org.jboss.system.server.profileservice.repository.SerializableDeploymentRepository@e1d5d9(root=/Applications/jboss-5.0.1.GA/server, key=org.jboss.profileservice.spi.ProfileKey@143b82c3[domain=default,server=default,name=default]) 18:21:30,436 INFO [ProfileServiceImpl] Loaded profile: ProfileImpl@ae002e{key=org.jboss.profileservice.spi.ProfileKey@143b82c3[domain=default,server=default,name=default]} 18:21:32,935 INFO [WebService] Using RMI server codebase: http://localhost:8083/ 18:21:42,572 INFO [NativeServerConfig] JBoss Web Services - Stack Native Core 18:21:42,573 INFO [NativeServerConfig] 3.0.5.GA 18:21:52,836 ERROR [AbstractKernelController] Error installing to ClassLoader: name=vfsfile:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/ state=Describe mode=Manual requiredState=ClassLoader org.jboss.deployers.spi.DeploymentException: Error creating classloader for vfsfile:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/ at org.jboss.deployers.spi.DeploymentException.rethrowAsDeploymentException(DeploymentException.java:49) at org.jboss.deployers.structure.spi.helpers.AbstractDeploymentContext.createClassLoader(AbstractDeploymentContext.java:576) at org.jboss.deployers.structure.spi.helpers.AbstractDeploymentUnit.createClassLoader(AbstractDeploymentUnit.java:159) at org.jboss.deployers.spi.deployer.helpers.AbstractClassLoaderDeployer.deploy(AbstractClassLoaderDeployer.java:53) at org.jboss.deployers.plugins.deployers.DeployerWrapper.deploy(DeployerWrapper.java:171) at org.jboss.deployers.plugins.deployers.DeployersImpl.doDeploy(DeployersImpl.java:1439) at org.jboss.deployers.plugins.deployers.DeployersImpl.doInstallParentFirst(DeployersImpl.java:1157) at org.jboss.deployers.plugins.deployers.DeployersImpl.install(DeployersImpl.java:1098) at org.jboss.dependency.plugins.AbstractControllerContext.install(AbstractControllerContext.java:348) at org.jboss.dependency.plugins.AbstractController.install(AbstractController.java:1598) at org.jboss.dependency.plugins.AbstractController.incrementState(AbstractController.java:934) at org.jboss.dependency.plugins.AbstractController.resolveContexts(AbstractController.java:1062) at org.jboss.dependency.plugins.AbstractController.resolveContexts(AbstractController.java:984) at org.jboss.dependency.plugins.AbstractController.change(AbstractController.java:822) at org.jboss.dependency.plugins.AbstractController.change(AbstractController.java:553) at org.jboss.deployers.plugins.deployers.DeployersImpl.process(DeployersImpl.java:781) at org.jboss.deployers.plugins.main.MainDeployerImpl.process(MainDeployerImpl.java:698) at org.jboss.system.server.profileservice.ProfileServiceBootstrap.loadProfile(ProfileServiceBootstrap.java:304) at org.jboss.system.server.profileservice.ProfileServiceBootstrap.start(ProfileServiceBootstrap.java:205) at org.jboss.bootstrap.AbstractServerImpl.start(AbstractServerImpl.java:405) at org.jboss.Main.boot(Main.java:209) at org.jboss.Main$1.run(Main.java:547) at java.lang.Thread.run(Thread.java:613) Caused by: java.lang.Error: Error visiting FileHandler@5567366[path=TwitterEAR.ear/TwitterPoCEJB.jar context=file:/Applications/jboss-5.0.1.GA/server/default/deploy/ real=file:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/TwitterPoCEJB.jar/] at org.jboss.classloading.plugins.vfs.PackageVisitor.determineAllPackages(PackageVisitor.java:98) at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.determineCapabilities(VFSDeploymentClassLoaderPolicyModule.java:108) at org.jboss.classloading.spi.dependency.Module.getCapabilities(Module.java:654) at org.jboss.classloading.spi.dependency.Module.determinePackageNames(Module.java:713) at org.jboss.classloading.spi.dependency.Module.getPackageNames(Module.java:698) at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.determinePolicy(VFSDeploymentClassLoaderPolicyModule.java:129) at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.determinePolicy(VFSDeploymentClassLoaderPolicyModule.java:48) at org.jboss.classloading.spi.dependency.policy.ClassLoaderPolicyModule.getPolicy(ClassLoaderPolicyModule.java:195) at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.getPolicy(VFSDeploymentClassLoaderPolicyModule.java:122) at org.jboss.deployers.vfs.plugins.classloader.VFSDeploymentClassLoaderPolicyModule.getPolicy(VFSDeploymentClassLoaderPolicyModule.java:48) at org.jboss.classloading.spi.dependency.policy.ClassLoaderPolicyModule.registerClassLoaderPolicy(ClassLoaderPolicyModule.java:131) at org.jboss.deployers.plugins.classloading.AbstractLevelClassLoaderSystemDeployer.createClassLoader(AbstractLevelClassLoaderSystemDeployer.java:120) at org.jboss.deployers.structure.spi.helpers.AbstractDeploymentContext.createClassLoader(AbstractDeploymentContext.java:562) ... 21 more Caused by: java.lang.RuntimeException: java.util.zip.ZipException: error in opening zip file at org.jboss.virtual.plugins.context.AbstractExceptionHandler.handleZipEntriesInitException(AbstractExceptionHandler.java:39) at org.jboss.virtual.plugins.context.helpers.NamesExceptionHandler.handleZipEntriesInitException(NamesExceptionHandler.java:63) at org.jboss.virtual.plugins.context.zip.ZipEntryContext.ensureEntries(ZipEntryContext.java:610) at org.jboss.virtual.plugins.context.zip.ZipEntryContext.checkIfModified(ZipEntryContext.java:757) at org.jboss.virtual.plugins.context.zip.ZipEntryContext.getChildren(ZipEntryContext.java:829) at org.jboss.virtual.plugins.context.zip.ZipEntryHandler.getChildren(ZipEntryHandler.java:159) at org.jboss.virtual.plugins.context.DelegatingHandler.getChildren(DelegatingHandler.java:121) at org.jboss.virtual.plugins.context.AbstractVFSContext.getChildren(AbstractVFSContext.java:211) at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:328) at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:298) at org.jboss.virtual.VFS.visit(VFS.java:433) at org.jboss.virtual.VirtualFile.visit(VirtualFile.java:437) at org.jboss.virtual.VirtualFile.getChildren(VirtualFile.java:386) at org.jboss.virtual.VirtualFile.getChildren(VirtualFile.java:367) at org.jboss.classloading.plugins.vfs.PackageVisitor.visit(PackageVisitor.java:200) at org.jboss.virtual.plugins.vfs.helpers.WrappingVirtualFileHandlerVisitor.visit(WrappingVirtualFileHandlerVisitor.java:62) at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:353) at org.jboss.virtual.plugins.context.AbstractVFSContext.visit(AbstractVFSContext.java:298) at org.jboss.virtual.VFS.visit(VFS.java:433) at org.jboss.virtual.VirtualFile.visit(VirtualFile.java:437) at org.jboss.classloading.plugins.vfs.PackageVisitor.determineAllPackages(PackageVisitor.java:94) ... 33 more Caused by: java.util.zip.ZipException: error in opening zip file at java.util.zip.ZipFile.open(Native Method) at java.util.zip.ZipFile.<init>(ZipFile.java:203) at java.util.zip.ZipFile.<init>(ZipFile.java:234) at org.jboss.virtual.plugins.context.zip.ZipFileWrapper.ensureZipFile(ZipFileWrapper.java:175) at org.jboss.virtual.plugins.context.zip.ZipFileWrapper.acquire(ZipFileWrapper.java:245) at org.jboss.virtual.plugins.context.zip.ZipEntryContext.initEntries(ZipEntryContext.java:470) at org.jboss.virtual.plugins.context.zip.ZipEntryContext.ensureEntries(ZipEntryContext.java:603) ... 51 more 18:21:56,772 INFO [JMXConnectorServerService] JMX Connector server: service:jmx:rmi://localhost/jndi/rmi://localhost:1090/jmxconnector 18:21:56,959 INFO [MailService] Mail Service bound to java:/Mail 18:21:59,450 WARN [JBossASSecurityMetadataStore] WARNING! POTENTIAL SECURITY RISK. It has been detected that the MessageSucker component which sucks messages from one node to another has not had its password changed from the installation default. Please see the JBoss Messaging user guide for instructions on how to do this. 18:21:59,489 WARN [AnnotationCreator] No ClassLoader provided, using TCCL: org.jboss.managed.api.annotation.ManagementComponent 18:21:59,789 INFO [TransactionManagerService] JBossTS Transaction Service (JTA version) - JBoss Inc. 18:21:59,789 INFO [TransactionManagerService] Setting up property manager MBean and JMX layer 18:22:00,040 INFO [TransactionManagerService] Initializing recovery manager 18:22:00,160 INFO [TransactionManagerService] Recovery manager configured 18:22:00,160 INFO [TransactionManagerService] Binding TransactionManager JNDI Reference 18:22:00,184 INFO [TransactionManagerService] Starting transaction recovery manager 18:22:01,243 INFO [Http11Protocol] Initializing Coyote HTTP/1.1 on http-localhost%2F127.0.0.1-8080 18:22:01,244 INFO [AjpProtocol] Initializing Coyote AJP/1.3 on ajp-localhost%2F127.0.0.1-8009 18:22:01,244 INFO [StandardService] Starting service jboss.web 18:22:01,247 INFO [StandardEngine] Starting Servlet Engine: JBoss Web/2.1.2.GA 18:22:01,336 INFO [Catalina] Server startup in 161 ms 18:22:01,360 INFO [TomcatDeployment] deploy, ctxPath=/invoker 18:22:02,014 INFO [TomcatDeployment] deploy, ctxPath=/web-console 18:22:02,459 INFO [TomcatDeployment] deploy, ctxPath=/jbossws 18:22:02,570 INFO [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/jboss-local-jdbc.rar/META-INF/ra.xml 18:22:02,586 INFO [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/jboss-xa-jdbc.rar/META-INF/ra.xml 18:22:02,645 INFO [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/jms-ra.rar/META-INF/ra.xml 18:22:02,663 INFO [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/mail-ra.rar/META-INF/ra.xml 18:22:02,705 INFO [RARDeployment] Required license terms exist, view vfszip:/Applications/jboss-5.0.1.GA/server/default/deploy/quartz-ra.rar/META-INF/ra.xml 18:22:02,801 INFO [SimpleThreadPool] Job execution threads will use class loader of thread: main 18:22:02,850 INFO [QuartzScheduler] Quartz Scheduler v.1.5.2 created. 18:22:02,857 INFO [RAMJobStore] RAMJobStore initialized. 18:22:02,858 INFO [StdSchedulerFactory] Quartz scheduler 'DefaultQuartzScheduler' initialized from default resource file in Quartz package: 'quartz.properties' 18:22:02,858 INFO [StdSchedulerFactory] Quartz scheduler version: 1.5.2 18:22:02,859 INFO [QuartzScheduler] Scheduler DefaultQuartzScheduler_$_NON_CLUSTERED started. 18:22:03,888 INFO [ConnectionFactoryBindingService] Bound ConnectionManager 'jboss.jca:service=DataSourceBinding,name=DefaultDS' to JNDI name 'java:DefaultDS' 18:22:04,530 INFO [ServerPeer] JBoss Messaging 1.4.1.GA server [0] started 18:22:04,624 INFO [QueueService] Queue[/queue/DLQ] started, fullSize=200000, pageSize=2000, downCacheSize=2000 18:22:04,632 WARN [ConnectionFactoryJNDIMapper] supportsFailover attribute is true on connection factory: jboss.messaging.connectionfactory:service=ClusteredConnectionFactory but post office is non clustered. So connection factory will *not* support failover 18:22:04,632 WARN [ConnectionFactoryJNDIMapper] supportsLoadBalancing attribute is true on connection factory: jboss.messaging.connectionfactory:service=ClusteredConnectionFactory but post office is non clustered. So connection factory will *not* support load balancing 18:22:04,742 INFO [ConnectionFactory] Connector bisocket://localhost:4457 has leasing enabled, lease period 10000 milliseconds 18:22:04,742 INFO [ConnectionFactory] org.jboss.jms.server.connectionfactory.ConnectionFactory@6af9ad started 18:22:04,746 INFO [QueueService] Queue[/queue/ExpiryQueue] started, fullSize=200000, pageSize=2000, downCacheSize=2000 18:22:04,747 INFO [ConnectionFactory] Connector bisocket://localhost:4457 has leasing enabled, lease period 10000 milliseconds 18:22:04,747 INFO [ConnectionFactory] org.jboss.jms.server.connectionfactory.ConnectionFactory@5ac953 started 18:22:04,750 INFO [ConnectionFactory] Connector bisocket://localhost:4457 has leasing enabled, lease period 10000 milliseconds 18:22:04,750 INFO [ConnectionFactory] org.jboss.jms.server.connectionfactory.ConnectionFactory@e8fa3a started 18:22:05,050 INFO [ConnectionFactoryBindingService] Bound ConnectionManager 'jboss.jca:service=ConnectionFactoryBinding,name=JmsXA' to JNDI name 'java:JmsXA' 18:22:05,073 INFO [TomcatDeployment] deploy, ctxPath=/ 18:22:05,178 INFO [TomcatDeployment] deploy, ctxPath=/jmx-console 18:22:05,290 ERROR [ProfileServiceBootstrap] Failed to load profile: Summary of incomplete deployments (SEE PREVIOUS ERRORS FOR DETAILS): DEPLOYMENTS IN ERROR: Deployment "vfsfile:/Applications/jboss-5.0.1.GA/server/default/deploy/TwitterEAR.ear/" is in error due to the following reason(s): java.util.zip.ZipException: error in opening zip file 18:22:05,301 INFO [Http11Protocol] Starting Coyote HTTP/1.1 on http-localhost%2F127.0.0.1-8080 18:22:05,364 INFO [AjpProtocol] Starting Coyote AJP/1.3 on ajp-localhost%2F127.0.0.1-8009 18:22:05,373 INFO [ServerImpl] JBoss (Microcontainer) [5.0.1.GA (build: SVNTag=JBoss_5_0_1_GA date=200902231221)] Started in 43s:467ms The mentioned ear and war file are both in the deploy directory. Does anybody have hints?

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• SOAP Web Service method naming conventions

  - by dbguy

  Consider a Web Service (e.g. SOAP-based) that has an operation which accepts a bulk of data from the client. From the server's point of view it is receiving data, but from the client's point of view it's sending data. How should that operation be named? The options are ImportData ExportData / SendData Is there a de facto standard for naming these things? How do web services usually name these? Thank you for your opinions.

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• Josh Smith's MVVM Demo App: Add commands to MainWindowViewModel's command list

  - by MAD9

  I have a question concerning Josh Smith's famous demo app on MVVM. I try building a "real" application around it to learn WPF. He creates this CommandsList in the MainWindowViewModel containing 2 Commands (create new and view all customers). This list is readonly (why? any particular reason?). I thougt it would be nice to add and remove some commands, depending on the workspace that is currently selected. Like edit or delete a customer when it has the focus and so on. How would I accomplish this?! Can I just make it a normal list and add commands? Or bind the Commands-View to a commands list of the selected workspace instead of the MainWindow? How? Any other ways? Please share your ideas! Thank you very much!

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