Search Results

Search found 50550 results on 2022 pages for 'method resolution order'.

Page 216/2022 | < Previous Page | 212 213 214 215 216 217 218 219 220 221 222 223  | Next Page >

  • Bad idea to have the same object, have a different side effect after method call.

    - by Nathan W
    Hi all, I'm having a bit of a gesign issue(again). Say I have this Buttonpad object: now this object is a wrapper object over one in a com object. At the moment it has a method on it called CreateInto(IComObject). Now to make a new button pad in the Com Object. You do: ButtonPad pad = new ButtonPad(); pad.Title = "Hello"; // Set some more properties. pad.CreateInto(Cominstance); The createinfo method will excute the right commands to buid the button pad in the com object. After it has been created it any calls against it are foward to the underlying object for change so: pad.Title = "New title"; will call the com object to set the title and also set the internal title variable. Basically any calls before the CreateInfo method only affect the .NET object anything after has the side effect of calling the com object also. I'm not very good at sequence diagrams but here is my attempt to explain whats going on: This doesn't feel good to me, it feels like I'm lying to the user about what the button pad does. I was going to have a object called WrappedButtonPad, which is returned from CreateInto and the user could make calls against that to make changes to the Com Object, but I feel having two objects that almost do the same thing but only differ by names might be even worse. Are these valid designs, or am I right to be worried? How else would you handle a object the can create and query a com object?

    Read the article

  • How to call implemented method of generic enum in Java?

    - by Justin Wiseman
    I am trying pass an enum into a method, iterate over that enums values, and call the method that that enum implements on all of those values. I am getting compiler errors on the part "value.getAlias()". It says "The method getAlias() is undefined for the type E" I have attempted to indicate that E implements the HasAlias interface, but it does not seem to work. Is this possible, and if so, how do I fix the code below to do what I want? The code below is only meant to show my process, it is not my intention to just print the names of the values in an enum, but to demonstate my problem. public interface HasAlias{ String getAlias(); }; public enum Letters implements HasAlias { A("The letter A"), B("The letter B"); private final String alias; public String getAlias(){return alias;} public Letters(String alias) { this.alias = alias; } } public enum Numbers implements HasAlias { ONE("The number one"), TWO("The number two"); private final String alias; public String getAlias(){return alias;} public Letters(String alias) { this.alias = alias; } } public class Identifier { public <E extends Enum<? extends HasAlias>> void identify(Class<E> enumClass) { for(E value : enumClass.getEnumConstants()) { System.out.println(value.getAlias()); } } }

    Read the article

  • My C# UploadFile method successfully uploads a file, but then my UI hangs...

    - by kyrathaba
    I have a simple WinForms test application in C#. Using the following method, I'm able to upload a file when I invoke the method from my button's Click event handler. The only problem is: my Windows Form "freezes". I can't close it using the Close button. I have to end execution from within the IDE (Visual C# 2010 Express edition). Here are the two methods: public void UploadFile(string FullPathFilename) { string filename = Path.GetFileName(FullPathFilename); try { FtpWebRequest request = (FtpWebRequest)WebRequest.Create(_remoteHost + filename); request.Method = WebRequestMethods.Ftp.UploadFile; request.Credentials = new NetworkCredential(_remoteUser, _remotePass); StreamReader sourceStream = new StreamReader(FullPathFilename); byte[] fileContents = Encoding.UTF8.GetBytes(sourceStream.ReadToEnd()); request.ContentLength = fileContents.Length; Stream requestStream = request.GetRequestStream(); requestStream.Write(fileContents, 0, fileContents.Length); FtpWebResponse response = (FtpWebResponse)request.GetResponse(); response.Close(); requestStream.Close(); sourceStream.Close(); } catch (Exception ex) { MessageBox.Show(ex.Message, "Upload error"); } finally { } } which gets called here: private void btnUploadTxtFile_Click(object sender, EventArgs e) { string username = "my_username"; string password = "my_password"; string host = "ftp://mywebsite.com"; try { clsFTPclient client = new clsFTPclient(host + "/httpdocs/non_church/", username, password); client.UploadFile(Path.GetDirectoryName(Application.ExecutablePath) + "\\myTextFile.txt"); } catch (Exception ex) { MessageBox.Show(ex.Message, "Upload problem"); } }

    Read the article

  • Is there anything inherently wrong with long variable/method names in Java?

    - by Doug Smith
    I know this is probably is a question of personal opinion, but I want to know what's standard practice and what would be frowned upon. One of my profs in university always seems to make his variable and method names as short as possible (getAmt() instead of getAmount) for instance. I have no objection to this, but personally, I prefer to have mine a little longer if it adds descriptiveness so the person reading it won't have to check or refer to documentation. For instance, we made a method that given a list of players, returns the player who scored the most goals. I made the method getPlayerWithMostGoals(), is this wrong? I toiled over choosing a way to make it shorter for awhile, but then I thought "why?". It gets the point across clearly and Eclipse makes it easy to autocomplete it when I type. I'm just wondering if the short variable names are a piece of the past due to needing everything to be as small as possible to be efficient. Is this still a requirement?

    Read the article

  • My method is too specific. How can I make it more generic?

    - by EricBoersma
    I have a class, the outline of which is basically listed below. import org.apache.commons.math.stat.Frequency; public class WebUsageLog { private Collection<LogLine> logLines; private Collection<Date> dates; WebUsageLog() { this.logLines = new ArrayList<LogLine>(); this.dates = new ArrayList<Date>(); } SortedMap<Double, String> getFrequencyOfVisitedSites() { SortedMap<Double, String> frequencyMap = new TreeMap<Double, String>(Collections.reverseOrder()); //we reverse order to sort from the highest percentage to the lowest. Collection<String> domains = new HashSet<String>(); Frequency freq = new Frequency(); for (LogLine line : this.logLines) { freq.addValue(line.getVisitedDomain()); domains.add(line.getVisitedDomain()); } for (String domain : domains) { frequencyMap.put(freq.getPct(domain), domain); } return frequencyMap; } } The intention of this application is to allow our Human Resources folks to be able to view Web Usage Logs we send to them. However, I'm sure that over time, I'd like to be able to offer the option to view not only the frequency of visited sites, but also other members of LogLine (things like the frequency of assigned categories, accessed types [text/html, img/jpeg, etc...] filter verdicts, and so on). Ideally, I'd like to avoid writing individual methods for compilation of data for each of those types, and they could each end up looking nearly identical to the getFrequencyOfVisitedSites() method. So, my question is twofold: first, can you see anywhere where this method should be improved, from a mechanical standpoint? And secondly, how would you make this method more generic, so that it might be able to handle an arbitrary set of data?

    Read the article

  • How do I pass three arrays from on method to another?

    - by user2966716
    I have a method studentSummary, that scans the input and creates three arrays examMark,courseworkMark and courseworkWeight. I need these arrays passing over to a different method, so I can use them to calculate moduleResult. heres my code: public static int[] studentSummary(int[] courseworkWeight2, int [] examMark2 , int [] courseworkMark2){ int examMark[] = { 0, 0, 0, 0, 0, 0 }; int courseworkMark[] = { 0, 0, 0, 0, 0, 0 }; Scanner resultInput = new Scanner(System.in); int courseworkWeight[] = { 0, 0, 0, 0, 0, 0 }; for (int k = 1; k < 7; k++) { System.out.print("Please enter exam marks for module " + k + ":"); examMark[k - 1] = resultInput.nextInt(); System.out.print("Please enter Coursework marks for module " + k + ":"); courseworkMark[k - 1] = resultInput.nextInt(); System.out.print("Please enter Coursework weighting for module " + k + ":"); courseworkWeight[k - 1] = resultInput.nextInt(); } Calculator method: public static int[] markCalculator() { int[] courseworkWeight = new int [6]; int[] courseworkMark = new int [6]; int[] examMark = new int [6]; for (int i = 0; i < 6; i++) { computedModuleMark = ((courseworkMark[i] * courseworkWeight[i]) + (examMark[i] * (100 - courseworkWeight[i]))) / 100; if ((computedModuleMark) < 35) { if (examMark[i]<35){ } } moduleMark[i] = computedModuleMark; } computeResult(moduleMark); StudentChart.draw(moduleMark); StudentChart.printSummary(moduleMark); return moduleMark; }

    Read the article

  • How to delay execution of a method in c#?

    - by Pandiya Chendur
    I have this if condition, if (sendSMS(Convert.ToInt32(DLComportNo.SelectedItem.Text), TxtDriMob.Text, TxtCliDet.Text) && sendSMS(Convert.ToInt32(DLComportNo.SelectedItem.Text), TxtCliMob.Text, TxtDriDet.Text)) { // I am inserting details to my db } and my sendSMS method looks like this, private bool sendSMS(int portNo, string mobNo, string details) { try { SerialPort SerialPort1 = new SerialPort(); SerialPort1.PortName = "COM" + portNo.ToString(); SerialPort1.BaudRate = 9600; SerialPort1.Parity = Parity.None; SerialPort1.DataBits = 8; SerialPort1.StopBits = StopBits.One; SerialPort1.RtsEnable = true; SerialPort1.DtrEnable = true; SerialPort1.Encoding.GetEncoder(); SerialPort1.ReceivedBytesThreshold = 1; SerialPort1.NewLine = Environment.NewLine; SerialPort1.Open(); SerialPort1.Write("AT" + SerialPort1.NewLine); Sleep(500); SerialPort1.Write("AT+CMGF=1" + SerialPort1.NewLine); Sleep(500); SerialPort1.Write("AT+CMGS=" + (char)34 + mobNo + (char)34 + SerialPort1.NewLine); Sleep(1000); SerialPort1.Write(details + (char)26); Sleep(2000); SerialPort1.Close(); } catch { } return true; } What happens is when i use break point in my sendSMS i get my output (ie) both the methods get executed and messages are sent properly... But when i removed my breakpoint both the methods in the if statement are executed but message from the first method is sent and not from the second method.... Any suggestion?

    Read the article

  • How can you pass an object from the form_for helper to a method?

    - by Alex
    So let's say I have a form which is being sent somewhere strange (and by strange we mean, NOT the default route: <% form_for @form_object, :url => {:controller => 'application', :action => 'form_action_thing'} do |f| %> <%= f.text_field :email %> <%= submit_tag 'Login' %> <% end %> Now let's say that we have the method that accepts it. def form_action_thing User.find(????? :email ?????) end My questions are thus: How does can I make the object @form_object available to the receiving method (in this case, form_action_tag)? I've tried params[:form_object], and I've scoured this site and the API, which I have to post below because SO doesn't believe I'm not a spammer (I'm a new member), as well as Googled as many permutations of this idea as I could think of. Nothing. Sorry if I missed something, i'm really trying. How do I address the object, once I've made it accessible to the method? Not params[:form_object], I'm guessing.

    Read the article

  • XSLT apply templates in different order of xml reading.

    - by David
    I am new to this, so please bear with me... If we have the following xml fragment: <docXML> <PARRAFO orden='1' tipo='parrafo'> <dato> <etiqueta>Título</etiqueta> <tipo>TextBox</tipo> <valor>¿Cuándo solicitar el consejo genético?</valor> <longitud>1500</longitud> <comentario></comentario> <enlace></enlace> <target_enlace>I</target_enlace> </dato> <dato> <etiqueta>Texto</etiqueta> <tipo>Resumen</tipo> <valor>Resumen text</valor> <longitud>8000</longitud> <comentario></comentario> <enlace></enlace> <target_enlace></target_enlace> </dato> <dato> <etiqueta>Imagen</etiqueta> <tipo>TextBox</tipo> <valor>http://url/Imagenes/7D2BE6480CF4486CA288A75932606181.jpg</valor> <longitud>1500</longitud> <comentario></comentario> <enlace></enlace> <target_enlace>I</target_enlace> </dato> </PARRAFO> <PARRAFO orden='1' tipo='parrafo'> <dato> <etiqueta>Título</etiqueta> <tipo>TextBox</tipo> <valor>TextBox text</valor> <longitud>1500</longitud> <comentario></comentario> <enlace></enlace> <target_enlace>I</target_enlace> </dato> <dato> <etiqueta>Texto</etiqueta> <tipo>Resumen</tipo> <valor>Resumen text</valor> <longitud>8000</longitud> <comentario></comentario> <enlace></enlace> <target_enlace></target_enlace> </dato> </PARRAFO> </docXML> .. I am going to apply templates to each section depending on the value of the label "etiqueta" per node "dato" in "PARRAFO" by using the following XSLT: <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:msxsl="urn:schemas-microsoft-com:xsl" exclude-result-prefixes="msxsl"> <xsl:output method="html" encoding="iso-8859-1"/> <xsl:template match="/"> <xsl:variable name="xml-doc-parrafo" select="documentoXML/PARRAFO"/> <!-- PARRAFOS --> <xsl:choose> <xsl:when test="count($xml-doc-parrafo)>0"> <div class="seccion_1"> <xsl:for-each select="$xml-doc-parrafo"> <xsl:choose> <xsl:when test="self::node()[@tipo = 'parrafo']"> <div class="parrafo"> <xsl:for-each select="self::node()[@tipo = 'parrafo']/dato"> <xsl:variable name="dato" select="self::node()[@tipo = 'parrafo']/dato"/> <xsl:variable name="nextdato" select="following::dato[1]/@etiqueta"/> <xsl:choose> <xsl:when test="etiqueta = 'Título'"> <xsl:call-template name="imprimeTituloParrafo"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:when test="etiqueta = 'Subtitulo'"> <xsl:call-template name="imprimeSubtituloParrafo"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:when test="etiqueta = 'Imagen'"> <xsl:call-template name="imprimeImagenParrafo"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:when test="etiqueta = 'Pie Imagen'"> <xsl:call-template name="imprimePieImagenParrafo"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:when test="etiqueta = 'Texto'"> <xsl:call-template name="imprimeTextoParrafo"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:when test="etiqueta = 'Pie Parrafo'"> <xsl:call-template name="imprimePieParrafo"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> </xsl:choose> </xsl:for-each> </div> </xsl:when> </xsl:choose> </xsl:for-each> </div> </xsl:when> <!-- si no hay resultados --> <xsl:otherwise> <br></br> <p style="text-align:center;">El documento no contiene datos.</p> </xsl:otherwise> </xsl:choose> </xsl:template> <xsl:template name="imprimeTituloParrafo"> <xsl:param name="etiqueta"></xsl:param> <xsl:param name="valor"></xsl:param> <xsl:param name="longitud"></xsl:param> <xsl:param name="enlace"></xsl:param> <xsl:param name="target_enlace"></xsl:param> <h2 class="titulo"> <xsl:choose> <xsl:when test="string-length($enlace) > 0"> <xsl:call-template name="imprimeEnlace"> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:otherwise> <xsl:value-of select="$valor"/> </xsl:otherwise> </xsl:choose> </h2> </xsl:template> <xsl:template name="imprimeSubtituloParrafo"> <xsl:param name="etiqueta"></xsl:param> <xsl:param name="valor"></xsl:param> <xsl:param name="longitud"></xsl:param> <xsl:param name="enlace"></xsl:param> <xsl:param name="target_enlace"></xsl:param> <h3 class="subtitulo"> <xsl:choose> <xsl:when test="string-length($enlace) > 0"> <xsl:call-template name="imprimeEnlace"> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:otherwise> <xsl:value-of select="$valor"/> </xsl:otherwise> </xsl:choose> </h3> </xsl:template> <xsl:template name="imprimeTextoParrafo"> <xsl:param name="etiqueta"></xsl:param> <xsl:param name="valor"></xsl:param> <xsl:param name="longitud"></xsl:param> <xsl:param name="enlace"></xsl:param> <xsl:param name="target_enlace"></xsl:param> <div class="texto"> <p class="texto"> <xsl:copy-of select="$valor/node()"/> </p> </div> </xsl:template> <xsl:template name="imprimeImagenParrafo"> <xsl:param name="etiqueta"></xsl:param> <xsl:param name="valor"></xsl:param> <xsl:param name="longitud"></xsl:param> <xsl:param name="comentario"></xsl:param> <xsl:param name="enlace"></xsl:param> <xsl:param name="target_enlace"></xsl:param> <xsl:choose> <xsl:when test="string-length($enlace) = 0"> <xsl:call-template name="imprimeImagen"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </xsl:when> <xsl:otherwise> <a> <xsl:choose> <xsl:when test="$target_enlace/node() = 'E'"> <xsl:attribute name="target"> <xsl:text>_blank</xsl:text> </xsl:attribute> </xsl:when> <xsl:when test="$target_enlace/node() = 'I'"> <xsl:attribute name="target"> <xsl:text>_self</xsl:text> </xsl:attribute> </xsl:when> </xsl:choose> <xsl:attribute name="href"> <xsl:value-of select="$enlace"/> </xsl:attribute> <xsl:call-template name="imprimeImagen"> <xsl:with-param name="etiqueta" select="etiqueta"></xsl:with-param> <xsl:with-param name="valor" select="valor"></xsl:with-param> <xsl:with-param name="longitud" select="longitud"></xsl:with-param> <xsl:with-param name="comentario" select="comentario"></xsl:with-param> <xsl:with-param name="enlace" select="enlace"></xsl:with-param> <xsl:with-param name="target_enlace" select="target_enlace"></xsl:with-param> </xsl:call-template> </a> </xsl:otherwise> </xsl:choose> </xsl:template> <xsl:template name="imprimeImagen"> <xsl:param name="etiqueta"></xsl:param> <xsl:param name="valor"></xsl:param> <xsl:param name="longitud"></xsl:param> <xsl:param name="comentario"></xsl:param> <xsl:param name="enlace"></xsl:param> <xsl:param name="target_enlace"></xsl:param> <div class="imagen_pie"> <img> <xsl:attribute name="src"> <xsl:value-of select="$valor"/> </xsl:attribute> <xsl:attribute name="alt"> <xsl:value-of select="$comentario"/> </xsl:attribute> </img> </div> </xsl:template> <xsl:template name="imprimeEnlace"> <xsl:param name="valor"></xsl:param> <xsl:param name="longitud"></xsl:param> <xsl:param name="comentario"></xsl:param> <xsl:param name="enlace"></xsl:param> <xsl:param name="target_enlace"></xsl:param> <a> <xsl:choose> <xsl:when test="$target_enlace/node() = 'E'"> <xsl:attribute name="target"> <xsl:text>_blank</xsl:text> </xsl:attribute> </xsl:when> <xsl:when test="$target_enlace/node() = 'I'"> </xsl:when> <xsl:when test="$target_enlace/node() = 'D'"> </xsl:when> </xsl:choose> <xsl:attribute name="href"> <xsl:value-of select="enlace"/> </xsl:attribute> <xsl:value-of select="$valor"/> </a> </xsl:template> .... </xsl:stylesheet> I need to first apply the template image (if exists in this "PARRAFO") "Imagen" just before the text "Texto" Now apply the template text first and then the image because it is before the text node before the image as shown in xml Thanks a lot!

    Read the article

  • Javscript passing and using that function

    - by Totty
    I have: var f1 = function(a){ alert(a) } var f2 = function(data, method){ method(data) // the problem is here, // the method f1 is not called. Is there a way to call that method f1? // the method f1 might not be in this scope, the method f1 can // be in a class or like this... } f2(a, f1) The question is: Is there a way to call that f1 from f2, from the passed method? thanks

    Read the article

  • Heaps of Trouble?

    - by Paul White NZ
    If you’re not already a regular reader of Brad Schulz’s blog, you’re missing out on some great material.  In his latest entry, he is tasked with optimizing a query run against tables that have no indexes at all.  The problem is, predictably, that performance is not very good.  The catch is that we are not allowed to create any indexes (or even new statistics) as part of our optimization efforts. In this post, I’m going to look at the problem from a slightly different angle, and present an alternative solution to the one Brad found.  Inevitably, there’s going to be some overlap between our entries, and while you don’t necessarily need to read Brad’s post before this one, I do strongly recommend that you read it at some stage; he covers some important points that I won’t cover again here. The Example We’ll use data from the AdventureWorks database, copied to temporary unindexed tables.  A script to create these structures is shown below: CREATE TABLE #Custs ( CustomerID INTEGER NOT NULL, TerritoryID INTEGER NULL, CustomerType NCHAR(1) COLLATE SQL_Latin1_General_CP1_CI_AI NOT NULL, ); GO CREATE TABLE #Prods ( ProductMainID INTEGER NOT NULL, ProductSubID INTEGER NOT NULL, ProductSubSubID INTEGER NOT NULL, Name NVARCHAR(50) COLLATE SQL_Latin1_General_CP1_CI_AI NOT NULL, ); GO CREATE TABLE #OrdHeader ( SalesOrderID INTEGER NOT NULL, OrderDate DATETIME NOT NULL, SalesOrderNumber NVARCHAR(25) COLLATE SQL_Latin1_General_CP1_CI_AI NOT NULL, CustomerID INTEGER NOT NULL, ); GO CREATE TABLE #OrdDetail ( SalesOrderID INTEGER NOT NULL, OrderQty SMALLINT NOT NULL, LineTotal NUMERIC(38,6) NOT NULL, ProductMainID INTEGER NOT NULL, ProductSubID INTEGER NOT NULL, ProductSubSubID INTEGER NOT NULL, ); GO INSERT #Custs ( CustomerID, TerritoryID, CustomerType ) SELECT C.CustomerID, C.TerritoryID, C.CustomerType FROM AdventureWorks.Sales.Customer C WITH (TABLOCK); GO INSERT #Prods ( ProductMainID, ProductSubID, ProductSubSubID, Name ) SELECT P.ProductID, P.ProductID, P.ProductID, P.Name FROM AdventureWorks.Production.Product P WITH (TABLOCK); GO INSERT #OrdHeader ( SalesOrderID, OrderDate, SalesOrderNumber, CustomerID ) SELECT H.SalesOrderID, H.OrderDate, H.SalesOrderNumber, H.CustomerID FROM AdventureWorks.Sales.SalesOrderHeader H WITH (TABLOCK); GO INSERT #OrdDetail ( SalesOrderID, OrderQty, LineTotal, ProductMainID, ProductSubID, ProductSubSubID ) SELECT D.SalesOrderID, D.OrderQty, D.LineTotal, D.ProductID, D.ProductID, D.ProductID FROM AdventureWorks.Sales.SalesOrderDetail D WITH (TABLOCK); The query itself is a simple join of the four tables: SELECT P.ProductMainID AS PID, P.Name, D.OrderQty, H.SalesOrderNumber, H.OrderDate, C.TerritoryID FROM #Prods P JOIN #OrdDetail D ON P.ProductMainID = D.ProductMainID AND P.ProductSubID = D.ProductSubID AND P.ProductSubSubID = D.ProductSubSubID JOIN #OrdHeader H ON D.SalesOrderID = H.SalesOrderID JOIN #Custs C ON H.CustomerID = C.CustomerID ORDER BY P.ProductMainID ASC OPTION (RECOMPILE, MAXDOP 1); Remember that these tables have no indexes at all, and only the single-column sampled statistics SQL Server automatically creates (assuming default settings).  The estimated query plan produced for the test query looks like this (click to enlarge): The Problem The problem here is one of cardinality estimation – the number of rows SQL Server expects to find at each step of the plan.  The lack of indexes and useful statistical information means that SQL Server does not have the information it needs to make a good estimate.  Every join in the plan shown above estimates that it will produce just a single row as output.  Brad covers the factors that lead to the low estimates in his post. In reality, the join between the #Prods and #OrdDetail tables will produce 121,317 rows.  It should not surprise you that this has rather dire consequences for the remainder of the query plan.  In particular, it makes a nonsense of the optimizer’s decision to use Nested Loops to join to the two remaining tables.  Instead of scanning the #OrdHeader and #Custs tables once (as it expected), it has to perform 121,317 full scans of each.  The query takes somewhere in the region of twenty minutes to run to completion on my development machine. A Solution At this point, you may be thinking the same thing I was: if we really are stuck with no indexes, the best we can do is to use hash joins everywhere. We can force the exclusive use of hash joins in several ways, the two most common being join and query hints.  A join hint means writing the query using the INNER HASH JOIN syntax; using a query hint involves adding OPTION (HASH JOIN) at the bottom of the query.  The difference is that using join hints also forces the order of the join, whereas the query hint gives the optimizer freedom to reorder the joins at its discretion. Adding the OPTION (HASH JOIN) hint results in this estimated plan: That produces the correct output in around seven seconds, which is quite an improvement!  As a purely practical matter, and given the rigid rules of the environment we find ourselves in, we might leave things there.  (We can improve the hashing solution a bit – I’ll come back to that later on). Faster Nested Loops It might surprise you to hear that we can beat the performance of the hash join solution shown above using nested loops joins exclusively, and without breaking the rules we have been set. The key to this part is to realize that a condition like (A = B) can be expressed as (A <= B) AND (A >= B).  Armed with this tremendous new insight, we can rewrite the join predicates like so: SELECT P.ProductMainID AS PID, P.Name, D.OrderQty, H.SalesOrderNumber, H.OrderDate, C.TerritoryID FROM #OrdDetail D JOIN #OrdHeader H ON D.SalesOrderID >= H.SalesOrderID AND D.SalesOrderID <= H.SalesOrderID JOIN #Custs C ON H.CustomerID >= C.CustomerID AND H.CustomerID <= C.CustomerID JOIN #Prods P ON P.ProductMainID >= D.ProductMainID AND P.ProductMainID <= D.ProductMainID AND P.ProductSubID = D.ProductSubID AND P.ProductSubSubID = D.ProductSubSubID ORDER BY D.ProductMainID OPTION (RECOMPILE, LOOP JOIN, MAXDOP 1, FORCE ORDER); I’ve also added LOOP JOIN and FORCE ORDER query hints to ensure that only nested loops joins are used, and that the tables are joined in the order they appear.  The new estimated execution plan is: This new query runs in under 2 seconds. Why Is It Faster? The main reason for the improvement is the appearance of the eager Index Spools, which are also known as index-on-the-fly spools.  If you read my Inside The Optimiser series you might be interested to know that the rule responsible is called JoinToIndexOnTheFly. An eager index spool consumes all rows from the table it sits above, and builds a index suitable for the join to seek on.  Taking the index spool above the #Custs table as an example, it reads all the CustomerID and TerritoryID values with a single scan of the table, and builds an index keyed on CustomerID.  The term ‘eager’ means that the spool consumes all of its input rows when it starts up.  The index is built in a work table in tempdb, has no associated statistics, and only exists until the query finishes executing. The result is that each unindexed table is only scanned once, and just for the columns necessary to build the temporary index.  From that point on, every execution of the inner side of the join is answered by a seek on the temporary index – not the base table. A second optimization is that the sort on ProductMainID (required by the ORDER BY clause) is performed early, on just the rows coming from the #OrdDetail table.  The optimizer has a good estimate for the number of rows it needs to sort at that stage – it is just the cardinality of the table itself.  The accuracy of the estimate there is important because it helps determine the memory grant given to the sort operation.  Nested loops join preserves the order of rows on its outer input, so sorting early is safe.  (Hash joins do not preserve order in this way, of course). The extra lazy spool on the #Prods branch is a further optimization that avoids executing the seek on the temporary index if the value being joined (the ‘outer reference’) hasn’t changed from the last row received on the outer input.  It takes advantage of the fact that rows are still sorted on ProductMainID, so if duplicates exist, they will arrive at the join operator one after the other. The optimizer is quite conservative about introducing index spools into a plan, because creating and dropping a temporary index is a relatively expensive operation.  It’s presence in a plan is often an indication that a useful index is missing. I want to stress that I rewrote the query in this way primarily as an educational exercise – I can’t imagine having to do something so horrible to a production system. Improving the Hash Join I promised I would return to the solution that uses hash joins.  You might be puzzled that SQL Server can create three new indexes (and perform all those nested loops iterations) faster than it can perform three hash joins.  The answer, again, is down to the poor information available to the optimizer.  Let’s look at the hash join plan again: Two of the hash joins have single-row estimates on their build inputs.  SQL Server fixes the amount of memory available for the hash table based on this cardinality estimate, so at run time the hash join very quickly runs out of memory. This results in the join spilling hash buckets to disk, and any rows from the probe input that hash to the spilled buckets also get written to disk.  The join process then continues, and may again run out of memory.  This is a recursive process, which may eventually result in SQL Server resorting to a bailout join algorithm, which is guaranteed to complete eventually, but may be very slow.  The data sizes in the example tables are not large enough to force a hash bailout, but it does result in multiple levels of hash recursion.  You can see this for yourself by tracing the Hash Warning event using the Profiler tool. The final sort in the plan also suffers from a similar problem: it receives very little memory and has to perform multiple sort passes, saving intermediate runs to disk (the Sort Warnings Profiler event can be used to confirm this).  Notice also that because hash joins don’t preserve sort order, the sort cannot be pushed down the plan toward the #OrdDetail table, as in the nested loops plan. Ok, so now we understand the problems, what can we do to fix it?  We can address the hash spilling by forcing a different order for the joins: SELECT P.ProductMainID AS PID, P.Name, D.OrderQty, H.SalesOrderNumber, H.OrderDate, C.TerritoryID FROM #Prods P JOIN #Custs C JOIN #OrdHeader H ON H.CustomerID = C.CustomerID JOIN #OrdDetail D ON D.SalesOrderID = H.SalesOrderID ON P.ProductMainID = D.ProductMainID AND P.ProductSubID = D.ProductSubID AND P.ProductSubSubID = D.ProductSubSubID ORDER BY D.ProductMainID OPTION (MAXDOP 1, HASH JOIN, FORCE ORDER); With this plan, each of the inputs to the hash joins has a good estimate, and no hash recursion occurs.  The final sort still suffers from the one-row estimate problem, and we get a single-pass sort warning as it writes rows to disk.  Even so, the query runs to completion in three or four seconds.  That’s around half the time of the previous hashing solution, but still not as fast as the nested loops trickery. Final Thoughts SQL Server’s optimizer makes cost-based decisions, so it is vital to provide it with accurate information.  We can’t really blame the performance problems highlighted here on anything other than the decision to use completely unindexed tables, and not to allow the creation of additional statistics. I should probably stress that the nested loops solution shown above is not one I would normally contemplate in the real world.  It’s there primarily for its educational and entertainment value.  I might perhaps use it to demonstrate to the sceptical that SQL Server itself is crying out for an index. Be sure to read Brad’s original post for more details.  My grateful thanks to him for granting permission to reuse some of his material. Paul White Email: [email protected] Twitter: @PaulWhiteNZ

    Read the article

  • How does this decorator make a call to the 'register' method?

    - by BryanWheelock
    I'm trying to understand what is going on in the decorator @not_authenticated. The next step in the TraceRoute is to the method 'register' which is also located in django_authopenid/views.py which I just don't understand because I don't see anywhere that register is even mentioned in signin() How is the method 'register' called? def not_authenticated(func): """ decorator that redirect user to next page if he is already logged.""" def decorated(request, *args, **kwargs): if request.user.is_authenticated(): next = request.GET.get("next", "/") return HttpResponseRedirect(next) return func(request, *args, **kwargs) return decorated @not_authenticated def signin(request,newquestion=False,newanswer=False): """ signin page. It manage the legacy authentification (user/password) and authentification with openid. url: /signin/ template : authopenid/signin.htm """ request.encoding = 'UTF-8' on_failure = signin_failure next = clean_next(request.GET.get('next')) form_signin = OpenidSigninForm(initial={'next':next}) form_auth = OpenidAuthForm(initial={'next':next}) if request.POST: if 'bsignin' in request.POST.keys() or 'openid_username' in request.POST.keys(): form_signin = OpenidSigninForm(request.POST) if form_signin.is_valid(): next = clean_next(form_signin.cleaned_data.get('next')) sreg_req = sreg.SRegRequest(optional=['nickname', 'email']) redirect_to = "%s%s?%s" % ( get_url_host(request), reverse('user_complete_signin'), urllib.urlencode({'next':next}) ) return ask_openid(request, form_signin.cleaned_data['openid_url'], redirect_to, on_failure=signin_failure, sreg_request=sreg_req) elif 'blogin' in request.POST.keys(): # perform normal django authentification form_auth = OpenidAuthForm(request.POST) if form_auth.is_valid(): user_ = form_auth.get_user() login(request, user_) next = clean_next(form_auth.cleaned_data.get('next')) return HttpResponseRedirect(next) question = None if newquestion == True: from forum.models import AnonymousQuestion as AQ session_key = request.session.session_key qlist = AQ.objects.filter(session_key=session_key).order_by('-added_at') if len(qlist) > 0: question = qlist[0] answer = None if newanswer == True: from forum.models import AnonymousAnswer as AA session_key = request.session.session_key alist = AA.objects.filter(session_key=session_key).order_by('-added_at') if len(alist) > 0: answer = alist[0] return render('authopenid/signin.html', { 'question':question, 'answer':answer, 'form1': form_auth, 'form2': form_signin, 'msg': request.GET.get('msg',''), 'sendpw_url': reverse('user_sendpw'), }, context_instance=RequestContext(request)) Looking at the request, it seems that account/register/ does reference the register method with 'PATH_INFO': u'/account/register/' Here is the request: <WSGIRequest GET:<QueryDict: {}>, POST:<QueryDict: {u'username': [u'BryanWheelock'], u'email': [u'[email protected]'], u'bnewaccount': [u'Signup']}>, COOKIES:{'__utma': '127460431.1218630960.1266769637.1266769637.1266864494.2', '__utmb': '127460431.3.10.1266864494', '__utmc': '127460431', '__utmz': '127460431.1266769637.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)', 'sessionid': 'fb15ee538320170a22d3a3a324aad968'}, META:{'CONTENT_LENGTH': '74', 'CONTENT_TYPE': 'application/x-www-form-urlencoded', 'DOCUMENT_ROOT': '/usr/local/apache2/htdocs', 'GATEWAY_INTERFACE': 'CGI/1.1', 'HTTP_ACCEPT': 'application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5', 'HTTP_ACCEPT_CHARSET': 'ISO-8859-1,utf-8;q=0.7,*;q=0.3', 'HTTP_ACCEPT_ENCODING': 'gzip,deflate,sdch', 'HTTP_ACCEPT_LANGUAGE': 'en-US,en;q=0.8', 'HTTP_CACHE_CONTROL': 'max-age=0', 'HTTP_CONNECTION': 'close', 'HTTP_COOKIE': '__utmz=127460431.1266769637.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); __utma=127460431.1218630960.1266769637.1266769637.1266864494.2; __utmc=127460431; __utmb=127460431.3.10.1266864494; sessionid=fb15ee538320170a22d3a3a324aad968', 'HTTP_HOST': 'workproject.com', 'HTTP_ORIGIN': 'http://workproject.com', 'HTTP_REFERER': 'http://workproject.com/account/signin/complete/?next=%2F&janrain_nonce=2010-02-22T18%3A49%3A53ZG2KXci&openid.ns=http%3A%2F%2Fspecs.openid.net%2Fauth%2F2.0&openid.mode=id_res&openid.op_endpoint=https%3A%2F%2Fwww.google.com%2Faccounts%2Fo8%2Fud&openid.response_nonce=2010-02-22T18%3A49%3A53Znxxxxxxxxxw&openid.return_to=http%3A%2F%2Fworkproject.com%2Faccount%2Fsignin%2Fcomplete%2F%3Fnext%3D%252F%26janrain_nonce%3D2010-02-22T18%253A49%253A53ZG2KXci&openid.assoc_handle=AOQobUepU4xs-kGg5LiyLzfN3RYv0I0Jocgjf_1odT4RR9zfMFpQVpMg&openid.signed=op_endpoint%2Cclaimed_id%2Cidentity%2Creturn_to%2Cresponse_nonce%2Cassoc_handle&openid.sig=Jf76i2RNhqpLTJMjeQ0nnQz6fgA%3D&openid.identity=https%3A%2F%2Fwww.google.com%2Faccounts%2Fo8%2Fid%3Fid%3DAItxxxxxxxxxs9CxHQ3PrHw_N5_3j1HM&openid.claimed_id=https%3A%2F%2Fwww.google.com%2Faccounts%2Fo8%2Fid%3Fid%3DAItOaxxxxxxxxxxx4s9CxHQ3PrHw_N5_3j1HM', 'HTTP_USER_AGENT': 'Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_8; en-US) AppleWebKit/532.9 (KHTML, like Gecko) Chrome/5.0.307.7 Safari/532.9', 'HTTP_X_FORWARDED_FOR': '96.8.31.235', 'PATH': '/usr/bin:/bin', 'PATH_INFO': u'/account/register/', 'PATH_TRANSLATED': '/home/spirituality/webapps/work/spirit_app.wsgi/account/register/', 'QUERY_STRING': '', 'REMOTE_ADDR': '127.0.0.1', 'REMOTE_PORT': '59956', 'REQUEST_METHOD': 'POST', 'REQUEST_URI': '/account/register/', 'SCRIPT_FILENAME': '/home/spirituality/webapps/spirituality/spirit_app.wsgi', 'SCRIPT_NAME': u'', 'SERVER_ADDR': '127.0.0.1', 'SERVER_ADMIN': '[no address given]', 'SERVER_NAME': 'workproject.com', 'SERVER_PORT': '80', 'SERVER_PROTOCOL': 'HTTP/1.0', 'SERVER_SIGNATURE': '', 'SERVER_SOFTWARE': 'Apache/2.2.12 (Unix) mod_wsgi/2.5 Python/2.5.4', 'mod_wsgi.application_group': 'www.workProject.com|', 'mod_wsgi.callable_object': 'application', 'mod_wsgi.listener_host': '', 'mod_wsgi.listener_port': '25931', 'mod_wsgi.process_group': '', 'mod_wsgi.reload_mechanism': '0', 'mod_wsgi.script_reloading': '1', 'mod_wsgi.version': (2, 5), 'wsgi.errors': <mod_wsgi.Log object at 0xb7ce0038>, 'wsgi.file_wrapper': <built-in method file_wrapper of mod_wsgi.Adapter object at 0xb7e94b18>, 'wsgi.input': <mod_wsgi.Input object at 0x999cc78>, 'wsgi.multiprocess': True, 'wsgi.multithread': False, 'wsgi.run_once': False, 'wsgi.url_scheme': 'http', 'wsgi.version': (1, 0)}>

    Read the article

  • Uninitialized constant Item::Types

    - by Rasmus
    Hi! First of, im a newbie ruby programmer so please bare with me if this is a very dumb question. I get this uninitialized constant error when i submit my nested forms. order.rb class Order < ActiveRecord::Base has_many :items, :dependent => :destroy has_many :types, :through => :items accepts_nested_attributes_for :items accepts_nested_attributes_for :types validates_associated :items validates_associated :types end item.rb class Item < ActiveRecord::Base has_one :types belongs_to :order accepts_nested_attributes_for :types validates_associated :types end type.rb class Type < ActiveRecord::Base belongs_to :items belongs_to :orders end new.erb.html <% form_for @order do |f| %> <%= f.error_messages %> <% f.fields_for :items do |builder| %> <table border="0"> <th>Type</th> <th>Amount</th> <th>Text</th> <th>Price</th> <tr> <% f.fields_for :type do |m| %> <td> <%= m.collection_select :type, Type.find(:all, :order => "created_at DESC"), :id, :name, {:prompt => "Select a Type" }, {:id => "selector", :onchange => "type_change(this)"} %> </td> <% end %> <td> <%= f.text_field :amount, :id => "amountField", :onchange => "change_total_price()" %> </td> <td> <%= f.text_field :text, :id => "textField" %> </td> <td> <%= f.text_field :price, :class => "priceField", :onChange => "change_total_price()" %> </td> <td> <%= link_to_remove_fields "Remove Item", f %> </td> </tr> </table> <% end %> <p><%= link_to_add_fields "Add Item", f, :items %></p> <p> <%= f.label :total_price %><br /> <%= f.text_field :total_price, :class => "priceField", :id => "totalPrice" %> </p> <p><%= f.submit "Create"%></p> <% end %> <%= link_to 'Back', orders_path %> create method in orders_controller.rb def create @order = Order.new(params[:order]) respond_to do |format| if @order.save flash[:notice] = 'Post was successfully created.' format.html { redirect_to(@order) } format.xml { render :xml => @order, :status => :created, :location => @order } else format.html { render :action => "new" } format.xml { render :xml => @order.errors, :status => :unprocessable_entity } end end end Hopefully you can see what i cant

    Read the article

  • servlet does not envoke when I call a from method.

    - by saloni
    My web.xml is like <web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <display-name>sample</display-name> <servlet> <servlet-name>Sampleclass</servlet-name> <servlet-class>sample.SampleClass</servlet-class> </servlet> <servlet-mapping> <servlet-name>Sampleclass</servlet-name> <url-pattern>/SampleClass</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>/page/form.jsp</welcome-file> </welcome-file-list> </web-app> and form.jsp <%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Insert title here</title> </head> <body> <h1>A simple web application</h1> <form method="POST" name="Sampleclass" action="SampleClass"> <label for="name">Enter your name </label> <input type="text" id="name" name="name"/><br><br> <input type="submit" value="Submit Form"/> <input type="reset" value="Reset Form"/> </form> </body> </html> and SampleClass.java is public class SampleClass extends HttpServlet { public void init(ServletConfig config) throws ServletException { super.init(config); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String name = request.getParameter("name"); String age = request.getParameter("age"); PrintWriter out = response.getWriter(); out.write("<html>Hello Your name is "+name +", and your age is "+age+"</html>"); } public void destroy() { } } but I am getting error when I entered to submit button of form.jsp and error is type Status report message HTTP method POST is not supported by this URL description The specified HTTP method is not allowed for the requested resource (HTTP method POST is not supported by this URL). I am not understanding that what is the problem exactly ? Please help..

    Read the article

  • Faster method for Matrix vector product for large matrix in C or C++ for use in GMRES

    - by user35959
    I have a large, dense matrix A, and I aim to find the solution to the linear system Ax=b using an iterative method (in MATLAB was the plan using its built in GMRES). For more than 10,000 rows, this is too much for my computer to store in memory, but I know that the entries in A are constructed by two known vectors x and y of length N and the entries satisfy: A(i,j) = .5*(x[i]-x[j])^2+([y[i]-y[j])^2 * log(x[i]-x[j])^2+([y[i]-y[j]^2). MATLAB's GMRES command accepts as input a function call that can compute the matrix vector product A*x, which allows me to handle larger matrices than I can store in memory. To write the matrix-vecotr product function, I first tried this in matlab by going row by row and using some vectorization, but I avoid spawning the entire array A (since it would be too large). This was fairly slow unfortnately in my application for GMRES. My plan was to write a mex file for MATLAB to, which is in C, and ideally should be significantly faster than the matlab code. I'm rather new to C, so this went rather poorly and my naive attempt at writing the code in C was slower than my partially vectorized attempt in Matlab. #include <math.h> #include "mex.h" void Aproduct(double *x, double *ctrs_x, double *ctrs_y, double *b, mwSize n) { mwSize i; mwSize j; double val; for (i=0; i<n; i++) { for (j=0; j<i; j++) { val = pow(ctrs_x[i]-ctrs_x[j],2)+pow(ctrs_y[i]-ctrs_y[j],2); b[i] = b[i] + .5* val * log(val) * x[j]; } for (j=i+1; j<n; j++) { val = pow(ctrs_x[i]-ctrs_x[j],2)+pow(ctrs_y[i]-ctrs_y[j],2); b[i] = b[i] + .5* val * log(val) * x[j]; } } } The above is the computational portion of the code for the matlab mex file (which is slightly modified C, if I understand correctly). Please note that I skip the case i=j, since in that case the variable val will be a 0*log(0), which should be interpreted as 0 for me, so I just skip it. Is there a more efficient or faster way to write this? When I call this C function via the mex file in matlab, it is quite slow, slower even than the matlab method I used. This surprises me since I suspected that C code should be much faster than matlab. The alternative matlab method which is partially vectorized that I am comparing it with is function Ax = Aprod(x,ctrs) n = length(x); Ax = zeros(n,1); for j=1:(n-3) v = .5*((ctrs(j,1)-ctrs(:,1)).^2+(ctrs(j,2)-ctrs(:,2)).^2).*log((ctrs(j,1)-ctrs(:,1)).^2+(ctrs(j,2)-ctrs(:,2)).^2); v(j)=0; Ax(j) = dot(v,x(1:n-3); end (the n-3 is because there is actually 3 extra components, but they are dealt with separately,so I excluded that code). This is partly vectorized and only needs one for loop, so it makes some sense that it is faster. However, I was hoping I could go even faster with C+mex file. Any suggestions or help would be greatly appreciated! Thanks! EDIT: I should be more clear. I am open to any faster method that can help me use GMRES to invert this matrix that I am interested in, which requires a faster way of doing the matrix vector product without explicitly loading the array into memory. Thanks!

    Read the article

  • What is the default resolution of the image saved by iPhone UIImagePicker? is it 1500 x 2000?

    - by zerlphr
    Hi, i have problem trying to find out the default resolution of the images taken and saved by UIImagePicker. I'm trying to merge the photo taken and another image from my library and without knowing what's the size of the image, i'm not able to merge the 2 images correctly. Another question is that: are there different resolutions for the different iphones such as 2g, 3g or 3gs?

    Read the article

  • How LINQ to Object statements work

    - by rajbk
    This post goes into detail as to now LINQ statements work when querying a collection of objects. This topic assumes you have an understanding of how generics, delegates, implicitly typed variables, lambda expressions, object/collection initializers, extension methods and the yield statement work. I would also recommend you read my previous two posts: Using Delegates in C# Part 1 Using Delegates in C# Part 2 We will start by writing some methods to filter a collection of data. Assume we have an Employee class like so: 1: public class Employee { 2: public int ID { get; set;} 3: public string FirstName { get; set;} 4: public string LastName {get; set;} 5: public string Country { get; set; } 6: } and a collection of employees like so: 1: var employees = new List<Employee> { 2: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 3: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 4: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 5: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 6: }; Filtering We wish to  find all employees that have an even ID. We could start off by writing a method that takes in a list of employees and returns a filtered list of employees with an even ID. 1: static List<Employee> GetEmployeesWithEvenID(List<Employee> employees) { 2: var filteredEmployees = new List<Employee>(); 3: foreach (Employee emp in employees) { 4: if (emp.ID % 2 == 0) { 5: filteredEmployees.Add(emp); 6: } 7: } 8: return filteredEmployees; 9: } The method can be rewritten to return an IEnumerable<Employee> using the yield return keyword. 1: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 2: foreach (Employee emp in employees) { 3: if (emp.ID % 2 == 0) { 4: yield return emp; 5: } 6: } 7: } We put these together in a console application. 1: using System; 2: using System.Collections.Generic; 3: //No System.Linq 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 15: }; 16: var filteredEmployees = GetEmployeesWithEvenID(employees); 17:  18: foreach (Employee emp in filteredEmployees) { 19: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 20: emp.ID, emp.FirstName, emp.LastName, emp.Country); 21: } 22:  23: Console.ReadLine(); 24: } 25: 26: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 27: foreach (Employee emp in employees) { 28: if (emp.ID % 2 == 0) { 29: yield return emp; 30: } 31: } 32: } 33: } 34:  35: public class Employee { 36: public int ID { get; set;} 37: public string FirstName { get; set;} 38: public string LastName {get; set;} 39: public string Country { get; set; } 40: } Output: ID 2 First_Name Jim Last_Name Ashlock Country UK ID 4 First_Name Jill Last_Name Anderson Country AUS Our filtering method is too specific. Let us change it so that it is capable of doing different types of filtering and lets give our method the name Where ;-) We will add another parameter to our Where method. This additional parameter will be a delegate with the following declaration. public delegate bool Filter(Employee emp); The idea is that the delegate parameter in our Where method will point to a method that contains the logic to do our filtering thereby freeing our Where method from any dependency. The method is shown below: 1: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 2: foreach (Employee emp in employees) { 3: if (filter(emp)) { 4: yield return emp; 5: } 6: } 7: } Making the change to our app, we create a new instance of the Filter delegate on line 14 with a target set to the method EmployeeHasEvenId. Running the code will produce the same output. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, filterDelegate); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  37: public class Employee { 38: public int ID { get; set;} 39: public string FirstName { get; set;} 40: public string LastName {get; set;} 41: public string Country { get; set; } 42: } Lets use lambda expressions to inline the contents of the EmployeeHasEvenId method in place of the method. The next code snippet shows this change (see line 15).  For brevity, the Employee class declaration has been skipped. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  The output displays the same two employees.  Our Where method is too restricted since it works with a collection of Employees only. Lets change it so that it works with any IEnumerable<T>. In addition, you may recall from my previous post,  that .NET 3.5 comes with a lot of predefined delegates including public delegate TResult Func<T, TResult>(T arg); We will get rid of our Filter delegate and use the one above instead. We apply these two changes to our code. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14:  15: foreach (Employee emp in filteredEmployees) { 16: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 17: emp.ID, emp.FirstName, emp.LastName, emp.Country); 18: } 19: Console.ReadLine(); 20: } 21: 22: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 23: foreach (var x in source) { 24: if (filter(x)) { 25: yield return x; 26: } 27: } 28: } 29: } We have successfully implemented a way to filter any IEnumerable<T> based on a  filter criteria. Projection Now lets enumerate on the items in the IEnumerable<Employee> we got from the Where method and copy them into a new IEnumerable<EmployeeFormatted>. The EmployeeFormatted class will only have a FullName and ID property. 1: public class EmployeeFormatted { 2: public int ID { get; set; } 3: public string FullName {get; set;} 4: } We could “project” our existing IEnumerable<Employee> into a new collection of IEnumerable<EmployeeFormatted> with the help of a new method. We will call this method Select ;-) 1: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 2: foreach (var emp in employees) { 3: yield return new EmployeeFormatted { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; 7: } 8: } The changes are applied to our app. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14: var formattedEmployees = Select(filteredEmployees); 15:  16: foreach (EmployeeFormatted emp in formattedEmployees) { 17: Console.WriteLine("ID {0} Full_Name {1}", 18: emp.ID, emp.FullName); 19: } 20: Console.ReadLine(); 21: } 22:  23: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 24: foreach (var x in source) { 25: if (filter(x)) { 26: yield return x; 27: } 28: } 29: } 30: 31: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 32: foreach (var emp in employees) { 33: yield return new EmployeeFormatted { 34: ID = emp.ID, 35: FullName = emp.LastName + ", " + emp.FirstName 36: }; 37: } 38: } 39: } 40:  41: public class Employee { 42: public int ID { get; set;} 43: public string FirstName { get; set;} 44: public string LastName {get; set;} 45: public string Country { get; set; } 46: } 47:  48: public class EmployeeFormatted { 49: public int ID { get; set; } 50: public string FullName {get; set;} 51: } Output: ID 2 Full_Name Ashlock, Jim ID 4 Full_Name Anderson, Jill We have successfully selected employees who have an even ID and then shaped our data with the help of the Select method so that the final result is an IEnumerable<EmployeeFormatted>.  Lets make our Select method more generic so that the user is given the freedom to shape what the output would look like. We can do this, like before, with lambda expressions. Our Select method is changed to accept a delegate as shown below. TSource will be the type of data that comes in and TResult will be the type the user chooses (shape of data) as returned from the selector delegate. 1:  2: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 3: foreach (var x in source) { 4: yield return selector(x); 5: } 6: } We see the new changes to our app. On line 15, we use lambda expression to specify the shape of the data. In this case the shape will be of type EmployeeFormatted. 1:  2: public class Program 3: { 4: [STAThread] 5: static void Main(string[] args) 6: { 7: var employees = new List<Employee> { 8: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 9: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 10: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 11: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 12: }; 13:  14: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 15: var formattedEmployees = Select(filteredEmployees, (emp) => 16: new EmployeeFormatted { 17: ID = emp.ID, 18: FullName = emp.LastName + ", " + emp.FirstName 19: }); 20:  21: foreach (EmployeeFormatted emp in formattedEmployees) { 22: Console.WriteLine("ID {0} Full_Name {1}", 23: emp.ID, emp.FullName); 24: } 25: Console.ReadLine(); 26: } 27: 28: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 29: foreach (var x in source) { 30: if (filter(x)) { 31: yield return x; 32: } 33: } 34: } 35: 36: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 37: foreach (var x in source) { 38: yield return selector(x); 39: } 40: } 41: } The code outputs the same result as before. On line 14 we filter our data and on line 15 we project our data. What if we wanted to be more expressive and concise? We could combine both line 14 and 15 into one line as shown below. Assuming you had to perform several operations like this on our collection, you would end up with some very unreadable code! 1: var formattedEmployees = Select(Where(employees, emp => emp.ID % 2 == 0), (emp) => 2: new EmployeeFormatted { 3: ID = emp.ID, 4: FullName = emp.LastName + ", " + emp.FirstName 5: }); A cleaner way to write this would be to give the appearance that the Select and Where methods were part of the IEnumerable<T>. This is exactly what extension methods give us. Extension methods have to be defined in a static class. Let us make the Select and Where extension methods on IEnumerable<T> 1: public static class MyExtensionMethods { 2: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 3: foreach (var x in source) { 4: if (filter(x)) { 5: yield return x; 6: } 7: } 8: } 9: 10: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 11: foreach (var x in source) { 12: yield return selector(x); 13: } 14: } 15: } The creation of the extension method makes the syntax much cleaner as shown below. We can write as many extension methods as we want and keep on chaining them using this technique. 1: var formattedEmployees = employees 2: .Where(emp => emp.ID % 2 == 0) 3: .Select (emp => new EmployeeFormatted { ID = emp.ID, FullName = emp.LastName + ", " + emp.FirstName }); Making these changes and running our code produces the same result. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new EmployeeFormatted { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (EmployeeFormatted emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } 55:  56: public class EmployeeFormatted { 57: public int ID { get; set; } 58: public string FullName {get; set;} 59: } Let’s change our code to return a collection of anonymous types and get rid of the EmployeeFormatted type. We see that the code produces the same output. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (var emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: public static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: public static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } To be more expressive, C# allows us to write our extension method calls as a query expression. Line 16 can be rewritten a query expression like so: 1: var formattedEmployees = from emp in employees 2: where emp.ID % 2 == 0 3: select new { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; When the compiler encounters an expression like the above, it simply rewrites it as calls to our extension methods.  So far we have been using our extension methods. The System.Linq namespace contains several extension methods for objects that implement the IEnumerable<T>. You can see a listing of these methods in the Enumerable class in the System.Linq namespace. Let’s get rid of our extension methods (which I purposefully wrote to be of the same signature as the ones in the Enumerable class) and use the ones provided in the Enumerable class. Our final code is shown below: 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; //Added 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 15: }; 16:  17: var formattedEmployees = from emp in employees 18: where emp.ID % 2 == 0 19: select new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: }; 23:  24: foreach (var emp in formattedEmployees) { 25: Console.WriteLine("ID {0} Full_Name {1}", 26: emp.ID, emp.FullName); 27: } 28: Console.ReadLine(); 29: } 30: } 31:  32: public class Employee { 33: public int ID { get; set;} 34: public string FirstName { get; set;} 35: public string LastName {get; set;} 36: public string Country { get; set; } 37: } 38:  39: public class EmployeeFormatted { 40: public int ID { get; set; } 41: public string FullName {get; set;} 42: } This post has shown you a basic overview of LINQ to Objects work by showning you how an expression is converted to a sequence of calls to extension methods when working directly with objects. It gets more interesting when working with LINQ to SQL where an expression tree is constructed – an in memory data representation of the expression. The C# compiler compiles these expressions into code that builds an expression tree at runtime. The provider can then traverse the expression tree and generate the appropriate SQL query. You can read more about expression trees in this MSDN article.

    Read the article

  • Having trouble returning a value from a method call when sending an array and the program is error out when run in reference to the sort

    - by programmerNOOB
    I am getting the following output when this program is run: Please enter the Social Security Number for taxpayer 0: 111111111 Please enter the gross income for taxpayer 0: 20000 Please enter the Social Security Number for taxpayer 1: 555555555 Please enter the gross income for taxpayer 1: 50000 Please enter the Social Security Number for taxpayer 2: 333333333 Please enter the gross income for taxpayer 2: 5464166 Please enter the Social Security Number for taxpayer 3: 222222222 Please enter the gross income for taxpayer 3: 645641 Please enter the Social Security Number for taxpayer 4: 444444444 Please enter the gross income for taxpayer 4: 29000 Taxpayer # 1 SSN: 111111111, Income is $20,000.00, Tax is $0.00 Taxpayer # 2 SSN: 555555555, Income is $50,000.00, Tax is $0.00 Taxpayer # 3 SSN: 333333333, Income is $5,464,166.00, Tax is $0.00 Taxpayer # 4 SSN: 222222222, Income is $645,641.00, Tax is $0.00 Taxpayer # 5 SSN: 444444444, Income is $29,000.00, Tax is $0.00 Unhandled Exception: System.InvalidOperationException: Failed to compare two elements in the array. --- System.ArgumentException: At least one object must implement IComparable. at System.Collections.Comparer.Compare(Object a, Object b) at System.Collections.Generic.ObjectComparer`1.Compare(T x, T y) at System.Collections.Generic.ArraySortHelper`1.SwapIfGreaterWithItems(T[] keys, IComparer`1 comparer, Int32 a, Int32 b) at System.Collections.Generic.ArraySortHelper`1.QuickSort(T[] keys, Int32 left, Int32 right, IComparer`1 comparer) at System.Collections.Generic.ArraySortHelper`1.Sort(T[] keys, Int32 index, Int32 length, IComparer`1 comparer) --- End of inner exception stack trace --- at System.Collections.Generic.ArraySortHelper`1.Sort(T[] keys, Int32 index, Int32 length, IComparer`1 comparer) at System.Array.Sort[T](T[] array, Int32 index, Int32 length, IComparer`1 comparer) at System.Array.Sort[T](T[] array) at Assignment5.Taxpayer.Main(String[] args) in Program.cs:line 150 Notice the 0s at the end of the line that should be the tax amount??? Here is the code: using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace taxes { class Rates { // Create a class named rates that has the following data members: private int incLimit; private double lowTaxRate; private double highTaxRate; // use read-only accessor public int IncomeLimit { get { return incLimit; } } public double LowTaxRate { get { return lowTaxRate; } } public double HighTaxRate { get { return highTaxRate; } } //A class constructor that assigns default values public Rates() { int limit = 30000; double lowRate = .15; double highRate = .28; incLimit = limit; lowTaxRate = lowRate; highTaxRate = highRate; } //A class constructor that takes three parameters to assign input values for limit, low rate and high rate. public Rates(int limit, double lowRate, double highRate) { } // A CalculateTax method that takes an income parameter and computes the tax as follows: public int CalculateTax(int income) { int limit = 0; double lowRate = 0; double highRate = 0; int taxOwed = 0; // If income is less than the limit then return the tax as income times low rate. if (income < limit) taxOwed = Convert.ToInt32(income * lowRate); // If income is greater than or equal to the limit then return the tax as income times high rate. if (income >= limit) taxOwed = Convert.ToInt32(income * highRate); return taxOwed; } } //end class Rates // Create a class named Taxpayer that has the following data members: public class Taxpayer { //Use get and set accessors. string SSN { get; set; } int grossIncome { get; set; } // Use read-only accessor. public int taxOwed { get { return taxOwed; } } // The Taxpayer class should be set up so that its objects are comparable to each other based on tax owed. class taxpayer : IComparable { public int taxOwed { get; set; } public int income { get; set; } int IComparable.CompareTo(Object o) { int returnVal; taxpayer temp = (taxpayer)o; if (this.taxOwed > temp.taxOwed) returnVal = 1; else if (this.taxOwed < temp.taxOwed) returnVal = -1; else returnVal = 0; return returnVal; } // End IComparable.CompareTo } //end taxpayer IComparable class // **The tax should be calculated whenever the income is set. // The Taxpayer class should have a getRates class method that has the following. public static void GetRates() { // Local method data members for income limit, low rate and high rate. int incLimit = 0; double lowRate; double highRate; string userInput; // Prompt the user to enter a selection for either default settings or user input of settings. Console.Write("Would you like the default values (D) or would you like to enter the values (E)?: "); /* If the user selects default the default values you will instantiate a rates object using the default constructor * and set the Taxpayer class data member for tax equal to the value returned from calling the rates object CalculateTax method.*/ userInput = Convert.ToString(Console.ReadLine()); if (userInput == "D" || userInput == "d") { Rates rates = new Rates(); rates.CalculateTax(incLimit); } // end if /* If the user selects to enter the rates data then prompt the user to enter values for income limit, low rate and high rate, * instantiate a rates object using the three-argument constructor passing those three entries as the constructor arguments and * set the Taxpayer class data member for tax equal to the valuereturned from calling the rates object CalculateTax method. */ if (userInput == "E" || userInput == "e") { Console.Write("Please enter the income limit: "); incLimit = Convert.ToInt32(Console.ReadLine()); Console.Write("Please enter the low rate: "); lowRate = Convert.ToDouble(Console.ReadLine()); Console.Write("Please enter the high rate: "); highRate = Convert.ToDouble(Console.ReadLine()); Rates rates = new Rates(incLimit, lowRate, highRate); rates.CalculateTax(incLimit); } } static void Main(string[] args) { Taxpayer[] taxArray = new Taxpayer[5]; Rates taxRates = new Rates(); // Implement a for-loop that will prompt the user to enter the Social Security Number and gross income. for (int x = 0; x < taxArray.Length; ++x) { taxArray[x] = new Taxpayer(); Console.Write("Please enter the Social Security Number for taxpayer {0}: ", x + 1); taxArray[x].SSN = Console.ReadLine(); Console.Write("Please enter the gross income for taxpayer {0}: ", x + 1); taxArray[x].grossIncome = Convert.ToInt32(Console.ReadLine()); } Taxpayer.GetRates(); // Implement a for-loop that will display each object as formatted taxpayer SSN, income and calculated tax. for (int i = 0; i < taxArray.Length; ++i) { Console.WriteLine("Taxpayer # {0} SSN: {1}, Income is {2:c}, Tax is {3:c}", i + 1, taxArray[i].SSN, taxArray[i].grossIncome, taxRates.CalculateTax(taxArray[i].grossIncome)); } // end for // Implement a for-loop that will sort the five objects in order by the amount of tax owed Array.Sort(taxArray); Console.WriteLine("Sorted by tax owed"); for (int i = 0; i < taxArray.Length; ++i) { Console.WriteLine("Taxpayer # {0} SSN: {1}, Income is {2:c}, Tax is {3:c}", i + 1, taxArray[i].SSN, taxArray[i].grossIncome, taxRates.CalculateTax(taxArray[i].grossIncome)); } } //end main } // end Taxpayer class } //end Any clues as to why the dollar amount is coming up as 0 and why the sort is not working?

    Read the article

  • What is this in error_log ? Invalid method in request \x16\x03\x01

    - by valter
    Hello. I found this line Invalid method in request \x16\x03\x01 on error_log file , and some other similiar lines like: [Wed Oct 27 23:16:37 2010] [error] [client 187.117.240.164] Invalid URI in request x\xb2\xa1:SMl\xcc{\xfd"\xd1\x91\x84!d\x0e~\xf6:\xfbVu\xdf\xc3\xdb[\xa9\xfe\xd3lpz\x92\xbf\x9f5\xa3\xbbvF\xbc\xee\x1a\xb1\xb0\xf8K\xecE\xbc\xe8r\xacx=\xc7>\xb5\xbd\xa3\xda\xe9\xf09\x95"fd\x1c\x05\x1c\xd5\xf3#:\x91\xe6WE\xdb\xadN;k14;\xdcr\xad\x9e\xa8\xde\x95\xc3\xebw\xa0\xb1N\x8c~\xf1\xcfSY\xd5zX\xd7\x0f\vH\xe4\xb5(\xcf,3\xc98\x19\xefYq@\xd2I\x96\xfb\xc7\xa9\xae._{S\xd1\x9c\xad\x17\xdci\x9b\xca\x93\xafSM\xb8\x99\xd9|\xc2\xd8\xc9\xe7\xe9O\x99\xad\x19\xc3V]\xcc\xddR\xf7$\xaa\xb8\x18\xe0f\xb8\xff Apache did a graceful restart a few seconds after the first error...

    Read the article

  • Alternative, more efficient scraping method for a noncoder, than Google doc's importxml and xpath?

    - by binarybunny
    I've searched throughout the net for a simple solution, but it seems everyone has their own unique method (coding language) of achieving this. I'm only just beginning to learn Linux, and my coding skills are thoroughly lacking (non-existent). I love the simplicity of using importxml and xpath, but copying and pasting values after reaching the spreadsheet limit of 50 is getting old. Now that I've seen the light, I would really just like to know of a simple, yet scalable solution to get more data into more spreadsheets/databases. Before I really start getting my hands dirty, I would love to know some of the ways you guys go about accomplishing this?

    Read the article

  • ffmpeg: converting an avi to a reduced, shareable flv/mp4...

    - by meder
    I recently followed a guide and recompiled my ffmpeg so x264 is enabled. I used some generic settings to convert my 700 MB avi file to a mp4 file, the result was a 407MB mp4 file. The original avi file's settings: Codec: DX50 Resolution: 704x304 Frame rate: 23.976023 Stream 1 Codec: mpga Type: Audio Channels: 2 Sample rate: 48000 Hz Bitrate 179 kb/s Command I used: ffmpeg -i input.avi -acodec libfaac -ab 128k -ac 2 -vcodec libx264 -vpre hq -crf 22 -threads 0 output.mp4 The settings of the output file (output.mp4): Codec: avc1 Resolution: 704x304 Display resolution: 704x304 Frame rate: 11.988011 Stream 1 Codec: mp4a Type: Audio Channels: 2 Sample Rate: 48000 Hz Bits per sample: 16 Bitrate: 1536 kb/s The quality of the output mp4 is pretty nice, it seems as if it's pretty much the same as the original source. However, I'm trying to reduce the filesize and I'm not really sure whether I should go with an flv format or keep it mp4. The advantage the flv would have obviously is that it would be playable with a flash player ( I have come across some swf players which take a flash parameter to play an flv file ).. but maybe I could use the video element, as I'm only going to be displaying this video privately so I don't have to worry about supporting legacy browsers such as IE. Can someone recommend some settings to specify in order for the filesize to be around ~100-150MB or so? I don't mind a reduction in quality, nor do I mind resizing it - I was going to do it initially but I wasn't sure what the guidelines were ( if any ) for dealing with resolution.. since this video's is 704x304 would it still be ok if I forced it into one that isn't perfectly fit for the aspect ratio? I have no clue about that part. I realize that I could have probably specified 28 instead of 22 for the CRF, I'm not sure if I should do that as opposed to maybe specifying smaller resolution, which might make it smaller as well?

    Read the article

  • How do I make solr/jetty find the installed slf4j jars in Ubuntu 12.04?

    - by J. Pablo Fernández
    I'm running Ubuntu 12.04's packaged Jetty in which I installed solr 4.3.1 (by copying the war file to /var/lib/jetty/webapps. When I start Jetty, I get this error: failed SolrRequestFilter: org.apache.solr.common.SolrException: Could not find necessary SLF4j logging jars. If using Jetty, the SLF4j logging jars need to go in the jetty lib/ext directory. The package libslf4j-java is installed, and the jars are in /usr/share/java: /usr/share/java/log4j-over-slf4j.jar /usr/share/java/slf4j-api.jar /usr/share/java/slf4j-jcl.jar /usr/share/java/slf4j-jdk14.jar /usr/share/java/slf4j-log4j12.jar /usr/share/java/slf4j-migrator.jar /usr/share/java/slf4j-nop.jar /usr/share/java/slf4j-simple.jar but somehow, Jetty and/or Solr are not finding them. How do I make them find them? or how do I install some other jars where jetty/solr would find them? The full error is: 88 [main] INFO org.mortbay.log - jetty-6.1.24 443 [main] INFO org.mortbay.log - Deploy /etc/jetty/contexts/javadoc.xml -> org.mortbay.jetty.handler.ContextHandler@cec0c5{/javadoc,file:/usr/share/jetty/javadoc} 522 [main] INFO org.mortbay.log - Extract file:/var/lib/jetty/webapps/solr.war to /var/cache/jetty/data/Jetty__8080_solr.war__solr__zdafkg/webapp 1501 [main] WARN org.mortbay.log - failed SolrRequestFilter: org.apache.solr.common.SolrException: Could not find necessary SLF4j logging jars. If using Jetty, the SLF4j logging jars need to go in the jetty lib/ext directory. For other containers, the corresponding directory should be used. For more information, see: http://wiki.apache.org/solr/SolrLogging 1501 [main] ERROR org.mortbay.log - Failed startup of context org.mortbay.jetty.webapp.WebAppContext@5329c5{/solr,file:/var/lib/jetty/webapps/solr.war} org.apache.solr.common.SolrException: Could not find necessary SLF4j logging jars. If using Jetty, the SLF4j logging jars need to go in the jetty lib/ext directory. For other containers, the corresponding directory should be used. For more information, see: http://wiki.apache.org/solr/SolrLogging at org.apache.solr.servlet.SolrDispatchFilter.<init>(SolrDispatchFilter.java:105) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:532) at java.lang.Class.newInstance0(Class.java:374) at java.lang.Class.newInstance(Class.java:327) at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:92) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:662) at org.mortbay.jetty.servlet.Context.startContext(Context.java:140) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:518) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:467) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152) at org.mortbay.jetty.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:156) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.Server.doStart(Server.java:224) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.xml.XmlConfiguration.main(XmlConfiguration.java:985) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.mortbay.start.Main.invokeMain(Main.java:194) at org.mortbay.start.Main.start(Main.java:534) at org.mortbay.jetty.start.daemon.Bootstrap.start(Bootstrap.java:30) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.apache.commons.daemon.support.DaemonLoader.start(DaemonLoader.java:243) Caused by: java.lang.NoClassDefFoundError: org/slf4j/LoggerFactory at org.apache.solr.servlet.SolrDispatchFilter.<init>(SolrDispatchFilter.java:103) ... 36 more Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory at java.net.URLClassLoader$1.run(URLClassLoader.java:217) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:205) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:392) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:363) ... 37 more 1505 [main] WARN org.mortbay.log - failed org.mortbay.jetty.webapp.WebAppContext@5329c5{/solr,file:/var/lib/jetty/webapps/solr.war}: java.lang.NoClassDefFoundError: org/slf4j/Logger 1579 [main] WARN org.mortbay.log - failed ContextHandlerCollection@19d0a1: java.lang.NoClassDefFoundError: org/slf4j/Logger 1582 [main] INFO org.mortbay.log - Opened /var/log/jetty/2013_06_27.request.log 1582 [main] WARN org.mortbay.log - failed HandlerCollection@cbf30e: java.lang.NoClassDefFoundError: org/slf4j/Logger 1582 [main] ERROR org.mortbay.log - Error starting handlers java.lang.NoClassDefFoundError: org/slf4j/Logger at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2454) at java.lang.Class.getMethod0(Class.java:2697) at java.lang.Class.getMethod(Class.java:1622) at org.mortbay.log.Log.unwind(Log.java:228) at org.mortbay.log.Log.warn(Log.java:197) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:475) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152) at org.mortbay.jetty.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:156) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.Server.doStart(Server.java:224) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50) at org.mortbay.xml.XmlConfiguration.main(XmlConfiguration.java:985) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.mortbay.start.Main.invokeMain(Main.java:194) at org.mortbay.start.Main.start(Main.java:534) at org.mortbay.jetty.start.daemon.Bootstrap.start(Bootstrap.java:30) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at org.apache.commons.daemon.support.DaemonLoader.start(DaemonLoader.java:243) Caused by: java.lang.ClassNotFoundException: org.slf4j.Logger at java.net.URLClassLoader$1.run(URLClassLoader.java:217) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:205) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:392) at org.mortbay.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:363) ... 29 more

    Read the article

  • Is there a method to export the URLs of the open tabs of a Firefox window?

    - by hekevintran
    If I have a Firefox window open that contains 10 tabs, is there a way in Firefox or by a plug-in to get the URLs of those 10 tabs as a text file or some other format? Right now if I want to do this I need to copy the URL of tab A, paste it somewhere, move to tab B, and repeat. I could also bookmark all the tabs into a folder and export that, but that seems like such a hassle. If there is no such method, could someone point me to some documents that describe the basics of writing a Firefox plug-in. I am willing to write this myself if there is no "standard" way.

    Read the article

  • Is there a general method to determine if a laptop can support 2x external monitors?

    - by Nick Alexeev
    Question: Is there a general method, which would let me determine if a laptop can support 2x external monitors? Context: I’m shopping for a laptop, which would support my 2 main modes of operation. In CAD mode, I sit at my desk and do many hours of work with OrCAD, Altium, SoligWorks. I’d like to have 2x external monitors. (If needed, monitors can be connected through dock station.) In field mode, I still need to run CAD packages, but only to look-up and tweak things occasionally. Field mode happens in vanilla indoor environments, so ruggedness and ingress protection are not needed. It would be nice if the laptop had a small footprint, like a 13” laptop perhaps. At the same time, weight and thickness of the laptop are not a problem for me. Of course, I also wonder if this is realistic at all. Any suggestion, insight or reference is really appreciated!

    Read the article

  • What is the best method to determine an account through DNS A record configuration?

    - by Matt
    I apologize if my description of the problem is unclear. I am working for an online CMS that allows external domains to be used similar to Tumblr or Flavors.me. I noticed both of these services simply require you to add an A record to your domain's DNS. When trying this, I added an A record for a blank name and "www" both leading to my webserver's IP. While this successfully routes to my server, it doesn't retain the used domain. This leaves me without any idea of what account they're attempting to reach at the application layer. I'm using nginx as my webserver. I have changed all the nameservers for a domain before, and that works properly, however that causes complications with other issues such as mail and isn't feasible on a scaled solution. What should I be doing here? Is the A record the correct method of accomplishing this? How are sites like Tumblr and Flavors.me determining which account is being referenced by the domain?

    Read the article

< Previous Page | 212 213 214 215 216 217 218 219 220 221 222 223  | Next Page >