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  • Detecting end of method chain in PHP?

    - by fabrik
    Hello! I cannot find a simple example about my question above: how can i detect the end of a method chain? I'm just looked Zend_Db_Select for example but this one is too complex for this simple question i think. Is it possible to catch the 'end' of a method chain in PHP? thanks, fabrik

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  • creating and returning an array from a method

    - by Troy
    howdy, i currently have a method that checks what is around the centre item in a 3x3 grid, if what is in the 8 adjacent positions is containing what i am checking for i want to mark that square on an array with length 7 as being 1. to do this i need to create and return an array in my method, is it possible to do this?

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  • Reference to an instance method of a particular object

    - by Andrey
    In the following code, if i try to pass method reference using the class name, works. But passing the reference variable compiler gives an error, i do not understand why? public class User { private String name; public User(String name) { this.name = name; } public void printName() { System.out.println(name); } } public class Main { public static void main(String[] args) { User u1 = new User("AAA"); User u2 = new User("BBB"); User u3 = new User("ZZZ"); List<User> userList = Arrays.asList(u1, u2, u3); userList.forEach(User::printName); // works userList.forEach(u1::printName); // compile error } } Thanks,

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  • WiX 3 Tutorial: Understanding main WXS and WXI file

    - by Mladen Prajdic
    In the previous post we’ve taken a look at the WiX solution/project structure and project properties. We’re still playing with our super SuperForm application and today we’ll take a look at the general parts of the main wxs file, SuperForm.wxs, and the wxi include file. For wxs file we’ll just go over the general description of what each part does in the code comments. The more detailed descriptions will be in future posts about features themselves. WXI include file Include files are exactly what their name implies. To include a wxi file into the wxs file you have to put the wxi at the beginning of each .wxs file you wish to include it in. If you’ve ever worked with C++ you can think of the include files as .h files. For example if you include SuperFormVariables.wxi into the SuperForm.wxs, the variables in the wxi won’t be seen in FilesFragment.wxs or RegistryFragment.wxs. You’d have to include it manually into those two wxs files too. For preprocessor variable $(var.VariableName) to be seen by every file in the project you have to include them in the WiX project properties->Build->“Define preprocessor variables” textbox. This is why I’ve chosen not to go this route because in multi developer teams not everyone has the same directory structure and having a single variable would mean each developer would have to checkout the wixproj file to edit the variable. This is pretty much unacceptable by my standards. This is why we’ve added a System Environment variable named SuperFormFilesDir as is shown in the previous Wix Tutorial post. Because the FilesFragment.wxs is autogenerated on every project build we don’t want to change it manually each time by adding the include wxi at the beginning of the file. This way we couldn’t recreate it in each pre-build event. <?xml version="1.0" encoding="utf-8"?><Include> <!-- Versioning. These have to be changed for upgrades. It's not enough to just include newer files. --> <?define MajorVersion="1" ?> <?define MinorVersion="0" ?> <?define BuildVersion="0" ?> <!-- Revision is NOT used by WiX in the upgrade procedure --> <?define Revision="0" ?> <!-- Full version number to display --> <?define VersionNumber="$(var.MajorVersion).$(var.MinorVersion).$(var.BuildVersion).$(var.Revision)" ?> <!-- Upgrade code HAS to be the same for all updates. Once you've chosen it don't change it. --> <?define UpgradeCode="YOUR-GUID-HERE" ?> <!-- Path to the resources directory. resources don't really need to be included in the project structure but I like to include them for for clarity --> <?define ResourcesDir="$(var.ProjectDir)\Resources" ?> <!-- The name of your application exe file. This will be used to kill the process when updating and creating the desktop shortcut --> <?define ExeProcessName="SuperForm.MainApp.exe" ?></Include> For now there’s no way to tell WiX in Visual Studio to have a wxi include file available to the whole project, so you have to include it in each file separately. Only variables set in “Define preprocessor variables” or System Environment variables are accessible to the whole project for now. The main WXS file: SuperForm.wxs We’ll only take a look at the general structure of the main SuperForm.wxs and not its the details. We’ll cover the details in future posts. The code comments should provide plenty info about what each part does in general. Basically there are 5 major parts. The update part, the conditions and actions part, the UI install sequence, the directory structure and the features we want to include. <?xml version="1.0" encoding="UTF-8"?><!-- Add xmlns:util namespace definition to be able to use stuff from WixUtilExtension dll--><Wix xmlns="http://schemas.microsoft.com/wix/2006/wi" xmlns:util="http://schemas.microsoft.com/wix/UtilExtension"> <!-- This is how we include wxi files --> <?include $(sys.CURRENTDIR)Includes\SuperFormVariables.wxi ?> <!-- Id="*" is to enable upgrading. * means that the product ID will be autogenerated on each build. Name is made of localized product name and version number. --> <Product Id="*" Name="!(loc.ProductName) $(var.VersionNumber)" Language="!(loc.LANG)" Version="$(var.VersionNumber)" Manufacturer="!(loc.ManufacturerName)" UpgradeCode="$(var.UpgradeCode)"> <!-- Define the minimum supported installer version (3.0) and that the install should be done for the whole machine not just the current user --> <Package InstallerVersion="300" Compressed="yes" InstallScope="perMachine"/> <Media Id="1" Cabinet="media1.cab" EmbedCab="yes" /> <!-- Upgrade settings. This will be explained in more detail in a future post --> <Upgrade Id="$(var.UpgradeCode)"> <UpgradeVersion OnlyDetect="yes" Minimum="$(var.VersionNumber)" IncludeMinimum="no" Property="NEWER_VERSION_FOUND" /> <UpgradeVersion Minimum="0.0.0.0" IncludeMinimum="yes" Maximum="$(var.VersionNumber)" IncludeMaximum="no" Property="OLDER_VERSION_FOUND" /> </Upgrade> <!-- Reference the global NETFRAMEWORK35 property to check if it exists --> <PropertyRef Id="NETFRAMEWORK35"/> <!-- Startup conditions that checks if .Net Framework 3.5 is installed or if we're running the OS higher than Windows XP SP2. If not the installation is aborted. By doing the (Installed OR ...) property means that this condition will only be evaluated if the app is being installed and not on uninstall or changing --> <Condition Message="!(loc.DotNetFrameworkNeeded)"> <![CDATA[Installed OR NETFRAMEWORK35]]> </Condition> <Condition Message="!(loc.AppNotSupported)"> <![CDATA[Installed OR ((VersionNT >= 501 AND ServicePackLevel >= 2) OR (VersionNT >= 502))]]> </Condition> <!-- This custom action in the InstallExecuteSequence is needed to stop silent install (passing /qb to msiexec) from going around it. --> <CustomAction Id="NewerVersionFound" Error="!(loc.SuperFormNewerVersionInstalled)" /> <InstallExecuteSequence> <!-- Check for newer versions with FindRelatedProducts and execute the custom action after it --> <Custom Action="NewerVersionFound" After="FindRelatedProducts"> <![CDATA[NEWER_VERSION_FOUND]]> </Custom> <!-- Remove the previous versions of the product --> <RemoveExistingProducts After="InstallInitialize"/> <!-- WixCloseApplications is a built in custom action that uses util:CloseApplication below --> <Custom Action="WixCloseApplications" Before="InstallInitialize" /> </InstallExecuteSequence> <!-- This will ask the user to close the SuperForm app if it's running while upgrading --> <util:CloseApplication Id="CloseSuperForm" CloseMessage="no" Description="!(loc.MustCloseSuperForm)" ElevatedCloseMessage="no" RebootPrompt="no" Target="$(var.ExeProcessName)" /> <!-- Use the built in WixUI_InstallDir GUI --> <UIRef Id="WixUI_InstallDir" /> <UI> <!-- These dialog references are needed for CloseApplication above to work correctly --> <DialogRef Id="FilesInUse" /> <DialogRef Id="MsiRMFilesInUse" /> <!-- Here we'll add the GUI logic for installation and updating in a future post--> </UI> <!-- Set the icon to show next to the program name in Add/Remove programs --> <Icon Id="SuperFormIcon.ico" SourceFile="$(var.ResourcesDir)\Exclam.ico" /> <Property Id="ARPPRODUCTICON" Value="SuperFormIcon.ico" /> <!-- Installer UI custom pictures. File names are made up. Add path to your pics. –> <!-- <WixVariable Id="WixUIDialogBmp" Value="MyAppLogo.jpg" /> <WixVariable Id="WixUIBannerBmp" Value="installBanner.jpg" /> --> <!-- the default directory structure --> <Directory Id="TARGETDIR" Name="SourceDir"> <Directory Id="ProgramFilesFolder"> <Directory Id="INSTALLLOCATION" Name="!(loc.ProductName)" /> </Directory> </Directory> <!-- Set the default install location to the value of INSTALLLOCATION (usually c:\Program Files\YourProductName) --> <Property Id="WIXUI_INSTALLDIR" Value="INSTALLLOCATION" /> <!-- Set the components defined in our fragment files that will be used for our feature --> <Feature Id="SuperFormFeature" Title="!(loc.ProductName)" Level="1"> <ComponentGroupRef Id="SuperFormFiles" /> <ComponentRef Id="cmpVersionInRegistry" /> <ComponentRef Id="cmpIsThisUpdateInRegistry" /> </Feature> </Product></Wix> For more info on what certain attributes mean you should look into the WiX Documentation.   WiX 3 tutorial by Mladen Prajdic navigation WiX 3 Tutorial: Solution/Project structure and Dev resources WiX 3 Tutorial: Understanding main wxs and wxi file WiX 3 Tutorial: Generating file/directory fragments with Heat.exe

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  • error X3501: 'main': entrypoint not found

    - by Pasha
    I am trying to learn DX10 by following this tutorial. However, my shader won't compile. Below is the detailed error message. Build started 9/10/2012 10:22:46 PM. 1>Project "D:\code\dx\Engine\Engine\Engine.vcxproj" on node 2 (Build target(s)). C:\Program Files (x86)\Windows Kits\8.0\bin\x86\fxc.exe /nologo /E"main" /Fo "D:\code\dx\Engine\Debug\color.cso" /Od /Zi color.fx 1>FXC : error X3501: 'main': entrypoint not found compilation failed; no code produced 1>Done Building Project "D:\code\dx\Engine\Engine\Engine.vcxproj" (Build target(s)) -- FAILED. Build FAILED. Time Elapsed 00:00:00.05 I can easily compile the downloaded code, but I want to know how to fix this error myself. My color.fx looks like this //////////////////////////////////////////////////////////////////////////////// // Filename: color.fx //////////////////////////////////////////////////////////////////////////////// ///////////// // GLOBALS // ///////////// matrix worldMatrix; matrix viewMatrix; matrix projectionMatrix; ////////////// // TYPEDEFS // ////////////// struct VertexInputType { float4 position : POSITION; float4 color : COLOR; }; struct PixelInputType { float4 position : SV_POSITION; float4 color : COLOR; }; //////////////////////////////////////////////////////////////////////////////// // Vertex Shader //////////////////////////////////////////////////////////////////////////////// PixelInputType ColorVertexShader(VertexInputType input) { PixelInputType output; // Change the position vector to be 4 units for proper matrix calculations. input.position.w = 1.0f; // Calculate the position of the vertex against the world, view, and projection matrices. output.position = mul(input.position, worldMatrix); output.position = mul(output.position, viewMatrix); output.position = mul(output.position, projectionMatrix); // Store the input color for the pixel shader to use. output.color = input.color; return output; } //////////////////////////////////////////////////////////////////////////////// // Pixel Shader //////////////////////////////////////////////////////////////////////////////// float4 ColorPixelShader(PixelInputType input) : SV_Target { return input.color; } //////////////////////////////////////////////////////////////////////////////// // Technique //////////////////////////////////////////////////////////////////////////////// technique10 ColorTechnique { pass pass0 { SetVertexShader(CompileShader(vs_4_0, ColorVertexShader())); SetPixelShader(CompileShader(ps_4_0, ColorPixelShader())); SetGeometryShader(NULL); } }

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  • Name disappeared from main menu bar

    - by Anthony Burman
    I have Ubuntu 10.4. I installed a nvidia gigabyte geforce 210 graphic card because the intel graphic card is a disaster. I use a terminal and basic, fiddly adjustments were successfully made to get the window to fit the screen. The new card is a roaring success. Nothing freezes and visuals can be set to Extra. But, from that point on, my main menu bar misbehaved and icons kept disappearing. Logon and logoff usually helped. R-E-I-S-U-B was needed when the actual logoff icon disappeared. My full name, Anthony Burman, appeared in the main menu bar. It was alonside Wanda, the Fish , the Oracle.... My name disappeared and I cannot get it back. It can't be found anywhere in the 'add to panel' section. Indicator applet session also can't bring it back. How do i re-insert my name on the toolbar? Thanks, Ant.

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  • Correct way to drive Main Loop in Cocoa

    - by Kyle
    I'm writing a game that currently runs in both Windows and Mac OS X. My main game loop looks like this: while(running) { ProcessOSMessages(); // Using Peek/Translate message in Win32 // and nextEventMatchingMask in Cocoa GameUpdate(); GameRender(); } Thats obviously simplified a bit, but thats the gist of it. In Windows where I have full control over the application, it works great. Unfortunately Apple has their own way of doing things in Cocoa apps. When I first tried to implement my main loop in Cocoa, I couldn't figure out where to put it so I created my own NSApplication per this post. I threw my GameFrame() right in my run function and everything worked correctly. However, I don't feel like its the "right" way to do it. I would like to play nicely within Apple's ecosystem rather than trying to hack a solution that works. This article from apple describes the old way to do it, with an NSTimer, and the "new" way to do it using CVDisplayLink. I've hooked up the CVDisplayLink version, but it just feels....odd. I don't like the idea of my game being driven by the display rather than the other way around. Are my only two options to use a CVDisplayLink or overwrite my own NSApplication? Neither one of those solutions feels quite right.

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  • Using "prevent execution of method" flags

    - by tpaksu
    First of all I want to point out my concern with some pseudocode (I think you'll understand better) Assume you have a global debug flag, or class variable named "debug", class a : var debug = FALSE and you use it to enable debug methods. There are two types of usage it as I know: first in a method : method a : if debug then call method b; method b : second in the method itself: method a : call method b; method b : if not debug exit And I want to know, is there any File IO or stack pointer wise difference between these two approaches. Which usage is better, safer and why?

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  • JUnit Easymock Unexpected method call

    - by Lancelot
    Hi, I'm trying to setup a test in JUnit w/ EasyMock and I'm running into a small issue that I can't seem to wrap my head around. I was hoping someone here could help. Here is a simplified version of the method I'm trying to test: public void myMethod() { //Some code executing here Obj myObj = this.service.getObj(param); if (myObj.getExtId() != null) { OtherObj otherObj = new OtherObj(); otherObj.setId(myObj.getExtId()); this.dao.insert(otherObj); } //Some code executing there } Ok so using EasyMock I've mocked the service.getObj(myObj) call and that works fine. My problem comes when JUnit hits the dao.insert(otherObj) call. EasyMock throws a "Unexpected Method Call" on it. I wouldn't mind mocking that dao in my test and using expectLastCall().once(); on it, but that assumes that I have a handle on the "otherObj" that's passed as a parameter at insert time... Which of course I don't since it's conditionally created within the context of the method being tested. Anyone has ever had to deal with that and somehow solved it? Thanks.

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  • Abstract Methods in "Product" - Factory Method C#

    - by Regina Foo
    I have a simple class library (COM+ service) written in C# to consume 5 web services: Add, Minus, Divide, Multiply and Compare. I've created the abstract product and abstract factory classes. The abstract product named WS's code: public abstract class WS { public abstract double Calculate(double a, double b); public abstract string Compare(double a, double b); } As you see, when one of the subclasses inherits WS, both methods must be overridden which might not be useful in some subclasses. E.g. Compare doesn't need Calculate() method. To instantiate a new CompareWS object, the client class will call the CreateWS() method which returns a WS object type. public class CompareWSFactory : WSFactory { public override WS CreateWS() { return new CompareWS(); } } But if Compare() is not defined as abstract in WS, the Compare() method cannot be invoked. This is only an example with two methods, but what if there are more methods? Is it stupid to define all the methods as abstract in the WS class? My question is: I want to define abstract methods that are common to all subclasses of WS whereas when the factory creates a WS object type, all the methods of the subclasses can be invoked (overridden methods of WS and also the methods in subclasses). How should I do this?

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  • Rails does not display error messages on a form in a custom method

    - by slythic
    Hi all, I've created a custom method called checkout in my app. I create an order (which is done my adding products to my "cart"), assign it to my client, and then I head to my checkout screen where I confirm the items and enter their customer order number and complete the order (submit). Everything works great except that it doesn't display error messages. I'm able to display a flash error notice (seen in complete_order method) when things go wrong but it doesn't specify the details like a normal form would. The error messages should appear if the customer order number is not unique for that client. Below is the custom method (checkout) related code. Order Model: validates_uniqueness_of :customer_order_number, :scope => :client_id Orders_controller: def checkout @order = current_order end def complete_order @order = current_order respond_to do |format| if @order.update_attributes(params[:order]) @order.complete #sets submitted datetime and state to 'complete' flash[:notice] = 'Thank you! Your order is being processed.' format.html { redirect_to( products_path ) } format.xml { head :ok } else flash[:error] = 'Please review your items' #added to confirm an error is present format.html { redirect_to( checkout_path ) } format.xml { render :xml => @order.errors, :status => :unprocessable_entity } end end end And the form in the checkout view: <% form_for @order, :url => { :controller => "orders", :action => "complete_order" } do |f| %> <%= f.error_messages %> <%= f.text_field :customer_order_number, :label => "Purchase Order Number" %> <p> <%= f.submit 'Complete Order', :confirm => 'Are you sure?' %> <small> or <%= link_to 'cancel', current_cart_path %></small> </p> <% end %> Any idea how I can display the specific error messages? Thank you in advance! -Tony

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  • Calling a method at a specific interval rate in C++

    - by Aetius
    This is really annoying me as I have done it before, about a year ago and I cannot for the life of me remember what library it was. Basically, the problem is that I want to be able to call a method a certain number of times or for a certain period of time at a specified interval. One example would be I would like to call a method "x" starting from now, 10 times, once every 0.5 seconds. Alternatively, call method "x" starting from now, 10 times, until 5 seconds have passed. Now I thought I used a boost library for this functionality but I can't seem to find it now and feeling a bit annoyed. Unfortunately I can't look at the code again as I'm not in possession of it any more. Alternatively, I could have dreamt this all up and it could have been proprietary code. Assuming there is nothing out there that does what I would like, what is currently the best way of producing this behaviour? It would need to be high-resolution, up to a millisecond. It doesn't matter if it blocks the thread that it is executed from or not. Thanks!

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  • How can I call a method given only its name?

    - by mfolnovich
    I'm trying to have method void run( string method ) which would run method in that class. For example: class Foo { public: void run( string method ) { // this method calls method *method* from this class } void bar() { printf( "Function bar\n" ); } void foo2() { printf( "Function foo2\n" ); } } Foo foo; int main( void ) { foo.run( "bar" ); foo.run( "foo2" ); } this would print: Function bar Function foo2 Thanks! :)

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  • asp.net detailsview update method not getting new values

    - by Ali
    Hi all, I am binding a detailsview with objectdatasource which gets the select parameter from the querystring. The detailsview shows the desired record, but when I try to update it, my update method gets the old values for the record (and hence no update). here is my detailsview code: <asp:DetailsView ID="dvUsers" runat="server" Height="50px" Width="125px" AutoGenerateRows="False" DataSourceID="odsUserDetails" onitemupdating="dvUsers_ItemUpdating"> <Fields> <asp:CommandField ShowEditButton="True" /> <asp:BoundField DataField="Username" HeaderText="Username" SortExpression="Username" ReadOnly="true" /> <asp:BoundField DataField="FirstName" HeaderText="First Name" SortExpression="FirstName" /> <asp:BoundField DataField="LastName" HeaderText="Last Name" SortExpression="LastName" /> <asp:BoundField DataField="Email" runat="server" HeaderText="Email" SortExpression="Email" /> <asp:BoundField DataField="IsActive" HeaderText="Is Active" SortExpression="IsActive" /> <asp:BoundField DataField="IsOnline" HeaderText="Is Online" SortExpression="IsOnline" ReadOnly="true" /> <asp:BoundField DataField="LastLoginDate" HeaderText="Last Login" SortExpression="LastLoginDate" ReadOnly="true" /> <asp:BoundField DataField="CreateDate" HeaderText="Member Since" SortExpression="CreateDate" ReadOnly="true" /> <asp:TemplateField HeaderText="Membership Ends" SortExpression="ExpiryDate"> <EditItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("ExpiryDate") %>'></asp:TextBox> <cc1:CalendarExtender ID="TextBox1_CalendarExtender" runat="server" Enabled="True" TargetControlID="TextBox1"> </cc1:CalendarExtender> </EditItemTemplate> <InsertItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("ExpiryDate") %>'></asp:TextBox> </InsertItemTemplate> <ItemTemplate> <asp:Label ID="Label1" runat="server" Text='<%# Bind("ExpiryDate") %>'></asp:Label> </ItemTemplate> </asp:TemplateField> </Fields> and here is the objectdatasource code: <asp:ObjectDataSource ID="odsUserDetails" runat="server" SelectMethod="GetAllUserDetailsByUserId" TypeName="QMS_BLL.Membership" UpdateMethod="UpdateUserForClient"> <UpdateParameters> <asp:Parameter Name="User_ID" Type="Int32" /> <asp:Parameter Name="firstName" Type="String" /> <asp:Parameter Name="lastName" Type="String" /> <asp:SessionParameter Name="updatedByUser" SessionField="userId" DefaultValue="1" /> <asp:Parameter Name="expiryDate" Type="DateTime" /> <asp:Parameter Name="Email" Type="String" /> <asp:Parameter Name="isActive" Type="String" /> </UpdateParameters> <SelectParameters> <asp:QueryStringParameter DefaultValue="1" Name="User_ID" QueryStringField="User_ID" Type="Int32" /> </SelectParameters> </asp:ObjectDataSource> Is the OnItemUpdating method still required when you have your custom BLL method called on insertevent? (which is being executed fine in my case but updating with the old values) or am I missing something else? Also I tried to provide an OnItemUpdating method and in there I tried to capture the contents of the textboxes (the new values). I got an exception: "Specified argument was out of the range of valid values. Parameter name: index" when I tried to do: TextBox txtFirstName = (TextBox)dvUsers.Rows[1].Cells[1].Controls[0]; Any help will be most appreciated.

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  • Does Java support dynamic method invocation?

    - by eSKay
    class A { void F() { System.out.println("a"); }} class B extends A { void F() { System.out.println("b"); }} public class X { public static void main(String[] args) { A objA = new B(); objA.F(); } } Here, F() is being invoked dynamically, isn't it? This article says ... the Java bytecode doesn’t support dynamic method invocation. There are three supported invocations modes : invokestatic, invokespecial, invokeinterface or invokevirtual. These modes allows to call methods with known signature. We talk of strongly typed language. This allows to to make some checks directly at compile time. On the other side, the dynamic languages use dynamic types. So we can call a method unknown at the compile time, but that’s completely impossible with the Java bytecode. What am I missing?

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  • Java and junit: derivative of polynomial method testing issue

    - by Curtis
    Hello all, im trying to finish up my junit testing for finding the derivative of a polynomial method and im having some trouble making it work. here is the method: public Polynomial derivative() { MyDouble a = new MyDouble(0); MyDouble b = this.a.add(this.a); MyDouble c = this.b; Polynomial poly = new Polynomial (a, b, c); return poly; } and here is the junit test: public void testDerivative() { MyDouble a = new MyDouble(2), b = new MyDouble(4), c = new MyDouble(8); MyDouble d = new MyDouble(0), e = new MyDouble(4), f = new MyDouble(4); Polynomial p1 = new Polynomial(a, b, c); Polynomial p2 = new Polynomial(d,e,f); assertTrue(p1.derivative().equals(p2)); } im not too sure why it isnt working...ive gone over it again and again and i know im missing something. thank you all for any help given, appreciate it

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  • How to find minimum of nonlinear, multivariate function using Newton's method (code not linear algeb

    - by Norman Ramsey
    I'm trying to do some parameter estimation and want to choose parameter estimates that minimize the square error in a predicted equation over about 30 variables. If the equation were linear, I would just compute the 30 partial derivatives, set them all to zero, and use a linear-equation solver. But unfortunately the equation is nonlinear and so are its derivatives. If the equation were over a single variable, I would just use Newton's method (also known as Newton-Raphson). The Web is rich in examples and code to implement Newton's method for functions of a single variable. Given that I have about 30 variables, how can I program a numeric solution to this problem using Newton's method? I have the equation in closed form and can compute the first and second derivatives, but I don't know quite how to proceed from there. I have found a large number of treatments on the web, but they quickly get into heavy matrix notation. I've found something moderately helpful on Wikipedia, but I'm having trouble translating it into code. Where I'm worried about breaking down is in the matrix algebra and matrix inversions. I can invert a matrix with a linear-equation solver but I'm worried about getting the right rows and columns, avoiding transposition errors, and so on. To be quite concrete: I want to work with tables mapping variables to their values. I can write a function of such a table that returns the square error given such a table as argument. I can also create functions that return a partial derivative with respect to any given variable. I have a reasonable starting estimate for the values in the table, so I'm not worried about convergence. I'm not sure how to write the loop that uses an estimate (table of value for each variable), the function, and a table of partial-derivative functions to produce a new estimate. That last is what I'd like help with. Any direct help or pointers to good sources will be warmly appreciated. Edit: Since I have the first and second derivatives in closed form, I would like to take advantage of them and avoid more slowly converging methods like simplex searches.

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  • Java input method for Virtual Keyboad

    - by shekhar
    Hi, I am facing problem in implementing Input method for Virtual Keyboard, currently I am using robot class for sending input to any application from virtual keyboard. but for that I need to create mapping of key-code and unicode, which is not consistent on different keyboard layout, can I directly pass the UNICODE to any application using Input method without worry about mapping between keycode and unicode. any useful link or sample code will be useful. It is simple Java program which is always on top of any application and work as onscreen keyboard. using a mouse while you press any button (key) of the keyboard, the corresponding character will be typed in the application running below. This is working perfectly for English Alphabets. I am facing problem while I am doing for unicode.

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  • Objective-C method implementation nuances

    - by altdotnetgeek
    I have just started to develop for the iPhone and am in the process of learning Objective-C. I have seen some code that implements a method in the @implementation side of a class like this: -(void)myMethod; { // method body } What makes this interesting is that there is no mention of myMethod in the @interface for the class. I tried a sample project with this and when I compile I get a warning from XCode that myMethod may not be seen by the calling code. Can anyone tell me what is going on? Thanks!

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  • execute javascript method after completing code behind method ?

    - by James123
    I can execute below callback() method after completion of document.getElementById('btnDownload').click(); .This Click is Code behind method. Now it is executing immediatly. I want wait "Click()" process done then Execute callback(); method. function LoadPopup() { // find the popup behavior this._popup = $find('mdlPopup'); // show the popup this._popup.show(); // synchronously run the server side validation ... document.getElementById('btnDownload').click(); callback(); } function callback() { this._popup = $find('mdlPopup'); // hide the popup this._popup.hide(); alert("hi"); }

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  • Java method overloading + double dispatch

    - by Max
    Can anybody explain in detail the reason the overloaded method print(Parent parent) is invoked when working with Child instance in my test piece of code? Any pecularities of virtual methods or methods overloading/resolution in Java involved here? Any direct reference to Java Lang Spec? Which term describes this behaviour? Thanks a lot. public class InheritancePlay { public static class Parent { public void doJob(Worker worker) { System.out.println("this is " + this.getClass().getName()); worker.print(this); } } public static class Child extends Parent { } public static class Worker { public void print(Parent parent) { System.out.println("Why this method resolution happens?"); } public void print(Child child) { System.out.println("This is not called"); } } public static void main(String[] args) { Child child = new Child(); Worker worker = new Worker(); child.doJob(worker); } }

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