Search Results

Search found 709 results on 29 pages for 'trees'.

Page 23/29 | < Previous Page | 19 20 21 22 23 24 25 26 27 28 29  | Next Page >

• secure user-authentication in squid: The Story

  - by Isaac

  once upon a time, there was a beautiful warm virtual-jungle in south america, and a squid server lived there. here is an perceptual image of the network: <the Internet> | | A | B Users <---------> [squid-Server] <---> [LDAP-Server] When the Users request access to the Internet, squid ask their name and passport, authenticate them by LDAP and if ldap approved them, then he granted them. Everyone was happy until some sniffers stole passport in path between users and squid [path A]. This disaster happened because squid used Basic-Authentication method. The people of jungle gathered to solve the problem. Some bunnies offered using NTLM of method. Snakes prefered Digest-Authentication while Kerberos recommended by trees. After all, many solution offered by people of jungle and all was confused! The Lion decided to end the situation. He shouted the rules for solutions: Shall the solution be secure! Shall the solution work for most of browsers and softwares (e.g. download softwares) Shall the solution be simple and do not need other huge subsystem (like Samba server) Shall not the method depend on special domain. (e.g. Active Directory) Then, a very resonable-comprehensive-clever solution offered by a monkey, making him the new king of the jungle! can you guess what was the solution? Tip: The path between squid and LDAP is protected by the lion, so the solution have not to secure it. Note: sorry for this boring and messy story! /~\/~\/~\ /\~/~\/~\/~\/~\ ((/~\/~\/~\/~\/~\)) (/~\/~\/~\/~\/~\/~\/~\) (//// ~ ~ \\\\) (\\\\( (0) (0) )////) (\\\\( __\-/__ )////) (\\\( /-\ )///) (\\\( (""""") )///) (\\\( \^^^/ )///) (\\\( )///) (\/~\/~\/~\/) ** (\/~\/~\/) *####* | | **** /| | | |\ \\ _/ | | | | \_ _________// Thanks! (,,)(,,)_(,,)(,,)--------'

  Read the article

• Box2d: Set active and inactive

  - by Rosarch

  I'm writing an XNA game in C# using the XNA port of Box2d - Box2dx. Entities like trees or zombies are represented as GameObjects. GameObjectManager adds and removes them from the game world: /// <summary> /// Does the work of removing the GameObject. /// </summary> /// <param name="controller">The GameObject to be removed.</param> private void removeGameObjectFromWorld(GameObjectController controller) { controllers.Remove(controller); worldState.Models.Remove(controller.Model); controller.Model.Body.SetActive(false); } public void addGameObjectToWorld(GameObjectController controller) { controllers.Add(controller); worldState.Models.Add(controller.Model); controller.Model.Body.SetActive(true); } controllers is a collection of GameObjectController instances. worldState.Models is a collection of GameObjectModel instances. When I remove GameObjects from Box2d this way, this method gets called: void IContactListener.EndContact(Contact contact) { GameObjectController collider1 = worldQueryUtils.gameObjectOfBody(contact.GetFixtureA().GetBody()); GameObjectController collider2 = worldQueryUtils.gameObjectOfBody(contact.GetFixtureB().GetBody()); collisionRecorder.removeCollision(collider1, collider2); } worldQueryUtils: // this could be cached if we know bodies never change public GameObjectController gameObjectOfBody(Body body) { return worldQueryEngine.GameObjectsForPredicate(x => x.Model.Body == body).Single(); } This method throws an error: System.InvalidOperationException was unhandled Message="Sequence contains no elements" Source="System.Core" StackTrace: at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source) at etc Why is this happening? What can I do to avoid it? This method has been called many times before the body.SetActive() was called. I feel that this may be messing it up.

  Read the article

• Selection Highlight in NSCollectionView

  - by Hooligancat

  On some occasions my head just hurts from banging it against the Cocoa wall. Today is one of those days. I have a working NSCollectionView with one minor, but critical, exception. Getting and highlighting the selected item within the collection. I've had all this working prior to Snow Leopard, but something appears to have changed and I can't quite place my finger on it, so I took my NSCollectionView right back to a basic test and followed Apple's documentation for creating an NSCollectionView here: http://developer.apple.com/mac/library/DOCUMENTATION/Cocoa/Conceptual/CollectionViews/Introduction/Introduction.html The collection view works fine following the quick start guide. However, this guide doesn't discuss selection other than "There are such features as incorporating image views, setting objects as selectable or not selectable and changing colors if they are selected". Using this as an example I went to the next step of binding the Array Controller to the NSCollectionView with the controller key selectionIndexes, thinking that this would bind any selection I make between the NSCollectionView and the array controller and thus firing off a KVO notification. I also set the NSCollectionView to be selectable in IB. There appears to be no selection delegate for NSCollectionView and unlike most Cocoa UI views, there appears to be no default selected highlight. So my problem really comes down to a related issue, but two distinct questions. How do I capture a selection of an item? How do I show a highlight of an item? NSCollectionView's programming guides seem to be few and far between and most searches via Google appear to pull up pre-Snow Leopard implementations, or use the view in a separate XIB file. For the latter (separate XIB file for the view), I don't see why this should be a pre-requisite otherwise I would have suspected that Apple would not have included the view in the same bundle as the collection view item. I know this is going to be a "can't see the wood for the trees" issue - so I'm prepared for the "doh!" moment. As usual, any and all help much appreciated.

  Read the article

• javadoc and overloaded methods

  - by skrebbel

  Hi all, I'm developing an API with many identically named methods that just differ by signature, which I guess is fairly common. They all do the same thing, except that they initialize various values by defaults if the user does not want to specify. As a digestible example, consider public interface Forest { public Tree addTree(); public Tree addTree(int amountOfLeaves); public Tree addTree(int amountOfLeaves, Fruit fruitType); public Tree addTree(int amountOfLeaves, int height); public Tree addTree(int amountOfLeaves, Fruit fruitType, int height); } The essential action performed by all of these methods is the same; a tree is planted in the forest. Many important things users of my API need to know about adding trees hold for all these methods. Ideally, I would like to write one Javadoc block that is used by all methods: /** * Plants a new tree in the forest. Please note that it may take * up to 30 years for the tree to be fully grown. * * @param amountOfLeaves desired amount of leaves. Actual amount of * leaves at maturity may differ by up to 10%. * @param fruitType the desired type of fruit to be grown. No warranties * are given with respect to flavour. * @param height desired hight in centimeters. Actual hight may differ by * up to 15%. */ In my imagination, a tool could magically choose which of the @params apply to each of the methods, and thus generate good docs for all methods at once. With Javadoc, if I understand it correctly, all I can do is essentially copy&paste the same javadoc block five times, with only a slightly differing parameter list for each method. This sounds cumbersome to me, and is also difficult to maintain. Is there any way around that? Some extension to javadoc that has this kind of support? Or is there a good reason why this is not supported that I missed?

  Read the article

• gunit syntax for tree walker with a flat list of nodes

  - by Kaleb Pederson

  Here's a simple gunit test for a portion of my tree grammar which generates a flat list of nodes: objectOption walks objectOption: <<one:"value">> -> (one "value") Although you define a tree in ANTLR's rewrite syntax using a caret (i.e. ^(ROOT child...)), gunit matches trees without the caret, so the above represents a tree and it's not surprising that it fails: it's a flat list of nodes and not a tree. This results in a test failure: 1 failures found: test2 (objectOption walks objectOption, line17) - expected: (one \"value\") actual: one \"value\" Another option which seems intuitive is to leave off the parenthesis, like this: objectOption walks objectOption: <<one:"value">> -> one "value" But gunit doesn't like this syntax. It seems to result in a parse failure in the gunit grammar: line 17:20 no viable alternative at input 'one' line 17:24 missing ':' at 'value' line 0:-1 no viable alternative at input '<EOF>' java.lang.NullPointerException at org.antlr.gunit.OutputTest.getExpected(OutputTest.java:65) at org.antlr.gunit.gUnitExecutor.executeTests(gUnitExecutor.java:245) ... What is the correct way to match a flat tree?

  Read the article

• Parsing an arithmetic expression and building a tree from it in Java

  - by ChocolateBear

  Hi, I needed some help with creating custom trees given an arithmetic expression. Say, for example, you input this arithmetic expression: (5+2)*7 The result tree should look like: * / \ + 7 / \ 5 2 I have some custom classes to represent the different types of nodes, i.e. PlusOp, LeafInt, etc. I don't need to evaluate the expression, just create the tree, so I can perform other functions on it later. Additionally, the negative operator '-' can only have one child, and to represent '5-2', you must input it as 5 + (-2). Some validation on the expression would be required to ensure each type of operator has the correct the no. of arguments/children, each opening bracket is accompanied by a closing bracket. Also, I should probably mention my friend has already written code which converts the input string into a stack of tokens, if that's going to be helpful for this. I'd appreciate any help at all. Thanks :) (I read that you can write a grammar and use antlr/JavaCC, etc. to create the parse tree, but I'm not familiar with these tools or with writing grammars, so if that's your solution, I'd be grateful if you could provide some helpful tutorials/links for them.)

  Read the article

• Exporting a non public Type through public API

  - by sachin

  I am trying to follow Trees tutorial at: http://cslibrary.stanford.edu/110/BinaryTrees.html Here is the code I have written so far: package trees.bst; import java.util.ArrayList; import java.util.List; import java.util.StringTokenizer; /** * * @author sachin */ public class BinarySearchTree { Node root = null; class Node { Node left = null; Node right = null; int data = 0; public Node(int data) { this.left = null; this.right = null; this.data = data; } } public void insert(int data) { root = insert(data, root); } public boolean lookup(int data) { return lookup(data, root); } public void buildTree(int numNodes) { for (int i = 0; i < numNodes; i++) { int num = (int) (Math.random() * 10); System.out.println("Inserting number:" + num); insert(num); } } public int size() { return size(root); } public int maxDepth() { return maxDepth(root); } public int minValue() { return minValue(root); } public int maxValue() { return maxValue(root); } public void printTree() { //inorder traversal System.out.println("inorder traversal:"); printTree(root); System.out.println("\n--------------"); } public void printPostorder() { //inorder traversal System.out.println("printPostorder traversal:"); printPostorder(root); System.out.println("\n--------------"); } public int buildTreeFromOutputString(String op) { root = null; int i = 0; StringTokenizer st = new StringTokenizer(op); while (st.hasMoreTokens()) { String stNum = st.nextToken(); int num = Integer.parseInt(stNum); System.out.println("buildTreeFromOutputString: Inserting number:" + num); insert(num); i++; } return i; } public boolean hasPathSum(int pathsum) { return hasPathSum(pathsum, root); } public void mirror() { mirror(root); } public void doubleTree() { doubleTree(root); } public boolean sameTree(BinarySearchTree bst) { //is this tree same as another given tree? return sameTree(this.root, bst.getRoot()); } public void printPaths() { if (root == null) { System.out.println("print path sum: tree is empty"); } List pathSoFar = new ArrayList(); printPaths(root, pathSoFar); } ///-------------------------------------------Public helper functions public Node getRoot() { return root; } //Exporting a non public Type through public API ///-------------------------------------------Helper Functions private boolean isLeaf(Node node) { if (node == null) { return false; } if (node.left == null && node.right == null) { return true; } return false; } ///----------------------------------------------------------- private boolean sameTree(Node n1, Node n2) { if ((n1 == null && n2 == null)) { return true; } else { if ((n1 == null || n2 == null)) { return false; } else { if ((n1.data == n2.data)) { return (sameTree(n1.left, n2.left) && sameTree(n1.right, n2.right)); } } } return false; } private void doubleTree(Node node) { //create a copy //bypass the copy to continue looping if (node == null) { return; } Node copyNode = new Node(node.data); Node temp = node.left; node.left = copyNode; copyNode.left = temp; doubleTree(copyNode.left); doubleTree(node.right); } private void mirror(Node node) { if (node == null) { return; } Node temp = node.left; node.left = node.right; node.right = temp; mirror(node.left); mirror(node.right); } private void printPaths(Node node, List pathSoFar) { if (node == null) { return; } pathSoFar.add(node.data); if (isLeaf(node)) { System.out.println("path in tree:" + pathSoFar); pathSoFar.remove(pathSoFar.lastIndexOf(node.data)); //only the current node, a node.data may be duplicated return; } else { printPaths(node.left, pathSoFar); printPaths(node.right, pathSoFar); } } private boolean hasPathSum(int pathsum, Node node) { if (node == null) { return false; } int val = pathsum - node.data; boolean ret = false; if (val == 0 && isLeaf(node)) { ret = true; } else if (val == 0 && !isLeaf(node)) { ret = false; } else if (val != 0 && isLeaf(node)) { ret = false; } else if (val != 0 && !isLeaf(node)) { //recurse further ret = hasPathSum(val, node.left) || hasPathSum(val, node.right); } return ret; } private void printPostorder(Node node) { //inorder traversal if (node == null) { return; } printPostorder(node.left); printPostorder(node.right); System.out.print(" " + node.data); } private void printTree(Node node) { //inorder traversal if (node == null) { return; } printTree(node.left); System.out.print(" " + node.data); printTree(node.right); } private int minValue(Node node) { if (node == null) { //error case: this is not supported return -1; } if (node.left == null) { return node.data; } else { return minValue(node.left); } } private int maxValue(Node node) { if (node == null) { //error case: this is not supported return -1; } if (node.right == null) { return node.data; } else { return maxValue(node.right); } } private int maxDepth(Node node) { if (node == null || (node.left == null && node.right == null)) { return 0; } int ldepth = 1 + maxDepth(node.left); int rdepth = 1 + maxDepth(node.right); if (ldepth > rdepth) { return ldepth; } else { return rdepth; } } private int size(Node node) { if (node == null) { return 0; } return 1 + size(node.left) + size(node.right); } private Node insert(int data, Node node) { if (node == null) { node = new Node(data); } else if (data <= node.data) { node.left = insert(data, node.left); } else { node.right = insert(data, node.right); } //control should never reach here; return node; } private boolean lookup(int data, Node node) { if (node == null) { return false; } if (node.data == data) { return true; } if (data < node.data) { return lookup(data, node.left); } else { return lookup(data, node.right); } } public static void main(String[] args) { BinarySearchTree bst = new BinarySearchTree(); int treesize = 5; bst.buildTree(treesize); //treesize = bst.buildTreeFromOutputString("4 4 4 6 7"); treesize = bst.buildTreeFromOutputString("3 4 6 3 6"); //treesize = bst.buildTreeFromOutputString("10"); for (int i = 0; i < treesize; i++) { System.out.println("Searching:" + i + " found:" + bst.lookup(i)); } System.out.println("tree size:" + bst.size()); System.out.println("maxDepth :" + bst.maxDepth()); System.out.println("minvalue :" + bst.minValue()); System.out.println("maxvalue :" + bst.maxValue()); bst.printTree(); bst.printPostorder(); int pathSum = 10; System.out.println("hasPathSum " + pathSum + ":" + bst.hasPathSum(pathSum)); pathSum = 6; System.out.println("hasPathSum " + pathSum + ":" + bst.hasPathSum(pathSum)); pathSum = 19; System.out.println("hasPathSum " + pathSum + ":" + bst.hasPathSum(pathSum)); bst.printPaths(); bst.printTree(); //bst.mirror(); System.out.println("Tree after mirror function:"); bst.printTree(); //bst.doubleTree(); System.out.println("Tree after double function:"); bst.printTree(); System.out.println("tree size:" + bst.size()); System.out.println("Same tree:" + bst.sameTree(bst)); BinarySearchTree bst2 = new BinarySearchTree(); bst2.buildTree(treesize); treesize = bst2.buildTreeFromOutputString("3 4 6 3 6"); bst2.printTree(); System.out.println("Same tree:" + bst.sameTree(bst2)); System.out.println("---"); } } Now the problem is that netbeans shows Warning: Exporting a non public Type through public API for function getRoot(). I write this function to get root of tree to be used in sameTree() function, to help comparison of "this" with given tree. Perhaps this is a OOP design issue... How should I restructure the above code that I do not get this warning and what is the concept I am missing here?

  Read the article

• Silverlight 4 Drag and Drop Treeview

  - by Rich

  Does anyone have an example for any of the following scenarios. Given, these are all dynamically populated trees. Not using a Heirarchal data template, but by iterating through object collections manually and appending children at the appropriate level. Treeview1 has 3 levels, but items can only be reordered within their level. So, lets say we have Drives, Folders and Files. Drives can be rearranged in an order, but not put into a Folder. When navigated down one level in a drive, the individual folders can be reordered, but not dragged between drives.. and same with files, only can be reordered, but not moved to a different folder or drive I have 2 treeviews, Treeview1 is the same as #1 above and Treeview2 is like a picklist of available items. A user can drag an item from Treeview2 to Treeview1, but it can only be placed at Treeview1's File Level. The dragged item cannot be a child of a file, or placed at the folder level, nor placed at the drive level. Also, how to handle the Above, On Top, or Below an item. I have yet to come across these examples.

  Read the article

• Source of parsers for programming languages?

  - by Arkaaito

  I'm dusting off an old project of mine which calculates a number of simple metrics about large software projects. One of the metrics is the length of files/classes/methods. Currently my code "guesses" where class/method boundaries are based on a very crude algorithm (traverse the file, maintaining a "current depth" and adjusting it whenever you encounter unquoted brackets; when you return to the level a class or method began on, consider it exited). However, there are many problems with this procedure, and a "simple" way of detecting when your depth has changed is not always effective. To make this give accurate results, I need to use the canonical way (in each language) of detecting function definitions, class definitions and depth changes. This amounts to writing a simple parser to generate parse trees containing at least these elements for every language I want my project to be applicable to. Obviously parsers have been written for all these languages before, so it seems like I shouldn't have to duplicate that effort (even though writing parsers is fun). Is there some open-source project which collects ready-to-use parser libraries for a bunch of source languages? Or should I just be using ANTLR to make my own from scratch? (Note: I'd be delighted to port the project to another language to make use of a great existing resource, so if you know of one, it doesn't matter what language it's written in.)

  Read the article

• AVL tree in C language

  - by I_S_W

  Hey all; i am currently doing a project that requires the use of AVL trees , the insert function i wrote for the avl does not seem to be working , it works for 3 or 4 nodes at maximum ; i would really appreciate your help The attempt is below enter code here Tree insert(Tree t,char name[80],int num) { if(t==NULL) { t=(Tree)malloc(sizeof(struct node)); if(t!=NULL) { strcpy(t->name,name); t->num=num; t->left=NULL; t->right=NULL; t->height=0; } } else if(strcmp(name,t->name)<0) { t->left=insert(t->left,name,num); if((height(t->left)-height(t->right))==2) if(strcmp(name,t->left->name)<0) { t=s_rotate_left(t);} else{ t=d_rotate_left(t);} } else if(strcmp(name,t-name)0) { t-right=insert(t-right,name,num); if((height(t-right)-height(t-left))==2) if(strcmp(name,t-right-name)0){ t=s_rotate_right(t); } else{ t=d_rotate_right(t);} } t-height=max(height(t-left),height(t-right))+1; return t; }

  Read the article

• Efficient Context-Free Grammar parser, preferably Python-friendly

  - by Max Shawabkeh

  I am in need of parsing a small subset of English for one of my project, described as a context-free grammar with (1-level) feature structures (example) and I need to do it efficiently . Right now I'm using NLTK's parser which produces the right output but is very slow. For my grammar of ~450 fairly ambiguous non-lexicon rules and half a million lexical entries, parsing simple sentences can take anywhere from 2 to 30 seconds, depending it seems on the number of resulting trees. Lexical entries have little to no effect on performance. Another problem is that loading the (25MB) grammar+lexicon at the beginning can take up to a minute. From what I can find in literature, the running time of the algorithm used to parse such a grammar (Earley or CKY) should be linear to the size of the grammar and cubic to the size of the input token list. My experience with NLTK indicates that ambiguity is what hurts the performance most, not the absolute size of the grammar. So now I'm looking for a CFG parser to replace NLTK. I've been considering PLY but I can't tell whether it supports feature structures in CFGs, which are required in my case, and the examples I've seen seem to be doing a lot of procedural parsing rather than just specifying a grammar. Can anybody show me an example of PLY both supporting feature structs and using a declarative grammar? I'm also fine with any other parser that can do what I need efficiently. A Python interface is preferable but not absolutely necessary.

  Read the article

• Java & Maven generating -and using- my own archetype

  - by Random

  Hello again! I have been busy in my project creating a webapp (in struts) that manages maven, using maven-2.2.1-uber.jar link text. The problem comes when the boss says it has to use some archetypes the company has created (so no predefined archetypes for you naughty boy!). So ok, I use the -DarchetypeRepository option (with ServletWrapper I get my complete web direction, becouse the repository will be inside the app), and the log seems to find it, but then the build fails -miserably- with this little text 'Build Failure - The defined artifact is not an archetype' as simple as that. Of course I have a lot of INFO lines that say abslutily nothig related. I have read the maven definitive guide searching for some kind of help, but it has been disapointing at best. My thoughts are thatmaybe I am missing in somewhere of all the folders tree some xml that actually sais maven that my pom.xml is an archetype not a project. But I really, really, can't find anything on the net or in the manuals that explains easy-handed how the archetype:generate (with special parameters) works and where I have to put every folder and/or file. So just to say my thoughts aloud (and hopefully you understand what I am trying to ask): I have a template where I do some xml changes (variables, etc...), then I have to call maen and do an archetype:generate with a variable project. The problem seems to be that my actual confuguration doesn't like what I am doing. After the generation of the archetype, witch luckly will create some directory trees and leave me a POM.xml somewhere I still have to do some variable changes and more xml manage stuff, so it whould be very kind from maven to don't destroy anything in this process. Any ideas why this maven-thing is not happly-ever-after asuming that my archetype is defintly an archetype? Allthought I think the code is ok, it could be wrong, as I am using maven-ubber and I call the actual CSMavenCli.main(String[, ClassWorld), I don't think it is the case this time. Thanks and all! :) Random.

  Read the article

• Simple Select Statement on MySQL Database Hanging

  - by AlishahNovin

  I have a very simple sql select statement on a very large table, that is non-normalized. (Not my design at all, I'm just trying to optimize while simultaneously trying to convince the owners of a redesign) Basically, the statement is like this: SELECT FirstName, LastName, FullName, State FROM Activity Where (FirstName=@name OR LastName=@name OR FullName=@name) AND State=@state; Now, FirstName, LastName, FullName and State are all indexed as BTrees, but without prefix - the whole column is indexed. State column is a 2 letter state code. What I'm finding is this: When @name = 'John Smith', and @state = '%' the search is really fast and yields results immediately. When @name = 'John Smith', and @state = 'FL' the search takes 5 minutes (and usually this means the web service times out...) When I remove the FirstName and LastName comparisons, and only use the FullName and State, both cases above work very quickly. When I replace FirstName, LastName, FullName, and State searches, but use LIKE for each search, it works fast for @name='John Smith%' and @state='%', but slow for @name='John Smith%' and @state='FL' When I search against 'John Sm%' and @state='FL' the search finds results immediately When I search against 'John Smi%' and @state='FL' the search takes 5 minutes. Now, just to reiterate - the table is not normalized. The John Smith appears many many times, as do many other users, because there is no reference to some form of users/people table. I'm not sure how many times a single user may appear, but the table itself has 90 Million records. Again, not my design... What I'm wondering is - though there are many many problems with this design, what is causing this specific problem. My guess is that the index trees are just too large that it just takes a very long time traversing the them. (FirstName, LastName, FullName) Anyway, I appreciate anyone's help with this. Like I said, I'm working on convincing them of a redesign, but in the meantime, if I someone could help me figure out what the exact problem is, that'd be fantastic.

  Read the article

• Is this a valid XPath expression?

  - by sid_com

  Is this xpath a valid XPath expression? (It does what it should ). #!/usr/bin/env perl use strict; use warnings; use 5.012; use XML::LibXML; my $string =<<EOS; <result> <cd> <artists> <artist class="1">Pumkinsingers</artist> <artist class="2">Max and Moritz</artist> </artists> <title>Hello, Hello</title> </cd> <cd> <artists> <artist class="3">Green Trees</artist> <artist class="4">The Leons</artist> </artists> <title>The Shield</title> </cd> </result> EOS #/ my $parser = XML::LibXML->new(); my $doc = $parser->load_xml( string => $string ); my $root = $doc->documentElement; my $xpath = '/result/cd[artists[artist[@class="2"]]]/title'; my @nodes = $root->findnodes( $xpath ); for my $node ( @nodes ) { say $node->textContent; }

  Read the article

• Variant datatype library for C

  - by Joey Adams

  Is there a decent open-source C library for storing and manipulating dynamically-typed variables (a.k.a. variants)? I'm primarily interested in atomic values (int8, int16, int32, uint, strings, blobs, etc.), while JSON-style arrays and objects as well as custom objects would also be nice. A major case where such a library would be useful is in working with SQL databases. The most obvious feature of such a library would be a single type for all supported values, e.g.: struct Variant { enum Type type; union { int8_t int8_; int16_t int16_; // ... }; }; Other features might include converting Variant objects to/from C structures (using a binding table), converting values to/from strings, and integration with an existing database library such as SQLite. Note: I do not believe this is question is a duplicate of http://stackoverflow.com/questions/649649/any-library-for-generic-datatypes-in-c , which refers to "queues, trees, maps, lists". What I'm talking about focuses more on making working with SQL databases roughly as smooth as working with them in interpreted languages.

  Read the article

• In a digital photo, how can I detect if a mountain is obscured by clouds?

  - by Gavin Brock

  The problem I have a collection of digital photos of a mountain in Japan. However the mountain is often obscured by clouds or fog. What techniques can I use to detect that the mountain is visible in the image? I am currently using Perl with the Imager module, but open to alternatives. All the images are taken from the exact same position - these are some samples. My naïve solution I started by taking several horizontal pixel samples of the mountain cone and comparing the brightness values to other samples from the sky. This worked well for differentiating good image 1 and bad image 2. However in the autumn it snowed and the mountain became brighter than the sky, like image 3, and my simple brightness test started to fail. Image 4 is an example of an edge case. I would classify this as a good image since some of the mountain is clearly visible. UPDATE 1 Thank you for the suggestions - I am happy you all vastly over-estimated my competence. Based on the answers, I have started trying the ImageMagick edge-detect transform, which gives me a much simpler image to analyze. convert sample.jpg -edge 1 edge.jpg I assume I should use some kind of masking to get rid of the trees and most of the clouds. Once I have the masked image, what is the best way to compare the similarity to a 'good' image? I guess the "compare" command suited for this job? How do I get a numeric 'similarity' value from this?

  Read the article

• Add new language to existing Xcode project localization

  - by leolobato

  Hey guys, I'm working on an existing Xcode 3.2.2 Universal iPhone OS project which is already localized for 4 languages (EN, IT, DE and FR). We are now adding a new language (JA) into this project. Each existing .lproj folder (en.lproj, it.lproj, de.lproj and fr.lproj) has almost 60 files - including PNGs, HTMLs and the Localizable.strings file. Each one of those files appear as localized groups inside Groups & Files in Xcode. They're spread all over the tree. If I right-click one of those groups (say, Localizable.strings) inside Xcode, Get Info, click on "Add Localization" and type "ja" - as the Xcode docs suggest, nothing happens. From what I read in this newgroup, it's possibly because of the way those folders are named. If they were named like English.lproj and Italian.lproj, this was supposed to work. So, for me to actually import a new language localized file into the existing group, I have to: Right-click the localized group file. Choose "Add Existing File". Select the corresponding file inside the ja.lproj folder. I'm about to get a new ja.lproj folder with those 60 localized files and would love to import them in the project in a way that doesn't involve searching for every single file in Groups & Trees and performing those steps... for every one of those 60 files. Is that possible? Is there a right (or better) way to import a new language into this Xcode project?

  Read the article

• Subclassing an NSTextField

  - by Hooligancat

  Given all the complex things I seem to cover every day, this appears to be a "what the heck am I doing wrong that seems to simple?" scenario! I would like to subclass an NSTextField to change the background color and text color. For simplicity sake (and to help anyone who hasn't ever subclassed anything before), here is the example of my (simplified) subclass MyNSTextFieldSubclass... Step 1: Create the subclass file: First the header file @interface MyTextFieldSubclass : NSTextField { } @end And the method file @implementation MyTextFieldSubclass -(NSColor *)backgroundColor { return [NSColor redColor]; } -(NSColor *)textColor { return [NSColor yellowColor]; } @end Step 2: Drag an NSTextField to a window in Interface Builder, select the Identity tab in the inspector and select the class MyTextFieldSubclass Step 3: Save the IB file, build and run the application Problem When I run the build, the text field does not reflect the color subclassing. However, I know the subclass is being called because if I add the following method, it gets called on text changes. -(void)textDidChange:(NSNotification *)notification { NSLog(@"My text changed"); } So why does the color change not occur on the text fields? I know that I can set the color in IB, but for anyone who has dealt with a lot of UI elements that all need the same styling, subclassing makes life way, way easier. Ironically, I have never had to subclass an NSTextField before and this one has me stumped. As usual, any and all help very much appreciated. I'm sure it will turn out to be a "Doh!" moment - just cant see the wood for the trees right now (plus I'm exhausted from watching too much World Cup Football early in the morning which never helps).

  Read the article

• Turning off hibernate logging console output

  - by Jared

  I'm using hibernate 3 and want to stop it from dumping all the startup messages to the console. I tried commenting out the stdout lines in log4j.properties but no luck. I've pasted my log file below. Also I'm using eclipse with the standard project structure and have a copy of log4j.properties in both the root of the project folder and the bin folder. ### direct log messages to stdout ### #log4j.appender.stdout=org.apache.log4j.ConsoleAppender #log4j.appender.stdout.Target=System.out #log4j.appender.stdout.layout=org.apache.log4j.PatternLayout #log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n ### direct messages to file hibernate.log ### log4j.appender.file=org.apache.log4j.FileAppender log4j.appender.file.File=hibernate.log log4j.appender.file.layout=org.apache.log4j.PatternLayout log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n ### set log levels - for more verbose logging change 'info' to 'debug' ### log4j.rootLogger=warn, stdout #log4j.logger.org.hibernate=info log4j.logger.org.hibernate=debug ### log HQL query parser activity #log4j.logger.org.hibernate.hql.ast.AST=debug ### log just the SQL #log4j.logger.org.hibernate.SQL=debug ### log JDBC bind parameters ### log4j.logger.org.hibernate.type=info #log4j.logger.org.hibernate.type=debug ### log schema export/update ### log4j.logger.org.hibernate.tool.hbm2ddl=debug ### log HQL parse trees #log4j.logger.org.hibernate.hql=debug ### log cache activity ### #log4j.logger.org.hibernate.cache=debug ### log transaction activity #log4j.logger.org.hibernate.transaction=debug ### log JDBC resource acquisition #log4j.logger.org.hibernate.jdbc=debug ### enable the following line if you want to track down connection ### ### leakages when using DriverManagerConnectionProvider ### #log4j.logger.org.hibernate.connection.DriverManagerConnectionProvider=trac5

  Read the article

• WPF: How do I get a reference to a styled window control in code behind?

  - by Brad

  I have a window defined with a style: <Window x:Class="winBorderless" x:Name="winBorderless" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:Local="clr-namespace:WindowStyle" Style="{StaticResource Window_Cartesia}" WindowStartupLocation="CenterScreen" BorderThickness="1" BorderBrush="#FF9CAAC1" Margin="5" Title="[Document Title]"> and the style defined in an application level dictionary: <Style x:Key="Window_Cartesia" TargetType="{x:Type Window}"> <Setter Property="WindowStyle" Value="None"/> <Setter Property="AllowsTransparency" Value="True"/> <Setter Property="Background" Value="Transparent"/> <EventSetter Event="Loaded" Handler="Loaded"/> <EventSetter Event="PreviewKeyDown" Handler="Preview_KeyDown"/> <EventSetter Event="MouseMove" Handler="FullScreen_MouseMove"/> <Setter Property="Template"> In code behind I have a reference to the Window instance set: Win = DirectCast(sender, winBorderless) This allows access to the window properties as the EventSetters pass references to the various controls. However, it doesn't provide for access to the controls defined in the style through the window reference as they don't exist there. So, what is the best way to reference a control through code behind that is defined in the style. I'd prefer not to iterate the trees to find them but ya gotta do....

  Read the article

• nHibernate Self Join Mapping

  - by kmoo01

  Hi Guys, This is probably incredibly simple, but I just cant see the wood for the trees at the moment. For brevity, I would like to model a word object, that has related words to it (synonyms), In doing so I could have the following mappings: <class name="Word" table="bs_word"> <id name="Id" column="WordId" type="Int32" unsaved-value="-1"> <generator class="native"> <param name="sequence"></param> </generator> </id> <property name="Key" column="word" type="String" length="50" /> <many-to-one name="SynonymGroup" class="BS.Core.Domain.Synonym, BS.Core" column="SynonymId" lazy="false"/> <class name="Synonym" table="bs_Synonym"> <id name="Id" column="SynonymId" type="Int32" unsaved-value="-1"> <generator class="native"> <param name="sequence"></param> </generator> </id> <property name="Alias" column="Alias" type="String" length="50" /> <bag name="Words" cascade="none" lazy="false" inverse="true"> <key column="SynonymId" /> <one-to-many class="Word" /> </bag> Mapping it like this would mean for a given word, I can access related words (synonyms) like this: word.SynonymGroup.Words However I would like to know if it is possible to map a bag of objects on an instance of a word object...if that makes sense, so I can access the related words like this: word.Words I've tried playing around with the map element, and composite elements, all to no avail - so I was wondering if some kind person could point me in the right direction? ta, kmoo01

  Read the article

• Collaborative filtering in MySQL ?

  - by user281434

  Hi I'm trying to develop a site that recommends items(fx. books) to users based on their preferences. So far, I've read O'Reilly's "Collective Intelligence" and numerous other online articles. They all, however, seem to deal with single instances of recommendation, for example if you like book A then you might like book B. What I'm trying to do is to create a set of 'preference-nodes' for each user on my site. Let's say a user likes book A,B and C. Then, when they add book D, I don't want the system to recommend other books based solely other users experience with book D. I wan't the system to look up similar 'preference-nodes' and recommend books based on that. Here's an example of 4 nodes: User1: 'book A'->'book B'->'book C' User2: 'book A'->'book B'->'book C'->'book D' user3: 'book X'->'book Y'->'book C'->'book Z' user4: 'book W'->'book Q'->'book C'->'book Z' So a recommendation system, as described in the material I've read, would recommend book Z to User 1, because there are two people who recommends Z in conjuction with liking C (ie. Z weighs more than D), even though a user with a similar 'preference-node', User2, would be more qualified to recommend book D because he has a more similar interest-pattern. So does any of you have any experience with this sort of thing? Is there some things I should try to read or does there exist any open source systems for this? Thanks for your time! Small edit: I think last.fm's algorithm is doing exactly what I my system to do. Using the preference-trees of people to recommmend music more personally to people. Instead of just saying "you might like B because you liked A"

  Read the article

• Dynamic Linq Property Converting to Sql

  - by Matthew Hood

  I am trying to understand dynamic linq and expression trees. Very basically trying to do an equals supplying the column and value as strings. Here is what I have so far private IQueryable<tblTest> filterTest(string column, string value) { TestDataContext db = new TestDataContext(); // The IQueryable data to query. IQueryable<tblTest> queryableData = db.tblTests.AsQueryable(); // Compose the expression tree that represents the parameter to the predicate. ParameterExpression pe = Expression.Parameter(typeof(tblTest), "item"); Expression left = Expression.Property(pe, column); Expression right = Expression.Constant(value); Expression e1 = Expression.Equal(left, right); MethodCallExpression whereCallExpression = Expression.Call( typeof(Queryable), "Where", new Type[] { queryableData.ElementType }, queryableData.Expression, Expression.Lambda<Func<tblTest, bool>>(e1, new ParameterExpression[] { pe })); // Create an executable query from the expression tree. IQueryable<tblTest> results = queryableData.Provider.CreateQuery<tblTest>(whereCallExpression); return results; } That works fine for columns in the DB. But fails for properties in my code eg public partial class tblTest { public string name_test { get { return name; } } } Giving an error cannot be that it cannot be converted into SQL. I have tried rewriting the property as a Expression<Func but with no luck, how can I convert simple properties so they can be used with linq in this dynamic way? Many Thanks

  Read the article

• A dynamic array of class "landmark", inside another single class "landmarks"

  - by pinnacler

  I'm working on a robot localization simulator and I created a class called "landmark". The end result is going to be a robot that is always centered and always faces the top of the screen. As it turns, the birds eye view map will rotate around the robot. To accomplish this, I'm assuming I can rotate one class and have all elements inside rotate as well. So, the landmark class has properties x,y, label, and radius. This is suppose to simulate a tree location in a forest. To test everything, I need "forest data," and I wrote a script to generate 100 trees in a 100m x 100m area. The script automatically generates values within an acceptable range for x,y, radius. The generated data is stored in an object called tempForest and is 100x3. Ideally, I want to create a class called "landmarks" (plural) that has 100 landmark instances inside. How would I instantiate 100 instances of landmark in one instance of landmarks using that randomly generated data? Ideally, I'd just type treeBeacons = landmarks(); and it would randomly populate 100 (user definable, set in config file) instances with x, y, radius data. I'm not sure how to deal with a dynamic array of class "Landmark", inside another single class "landmarks." Any ideas?

  Read the article

• Moral fits the story or suggest me a nice moral?

  - by Gobi

  A 25 year old son was sitting beside his old father in a train one day. When the train was about to leave, all the passengers started settling down in their seats. The son was filled with joy and anxiety. He was seated by the window. He put his hand out and felt the breeze and screamed, “ Papa look at all the trees, they are moving behind”. The old father smiled and admired his son’s feelings. Beside the old man, a couple was also travelling and observed this strange behavior. They found something awkward and childish in the behavior of this 25 year old man. All of a sudden, the son shouted again “Papa see! The clouds are moving about; there is a pond down and many cows are drinking it’s water”. It soon started drizzling. Once again, the young man felt exited and said “papa, I can see and feel the rain drops touching my hand”. The couple seeing this and feeling concerned, asked the old man “why don’t you consult a good doctor and treat your son; don’t you find something abnormally different in him ?” The old man replied, “Yes, I have provided the best treatment for my only boy. We are just returning from the hospital. I am happy for today is the day he has received his sense of sight. It’s for the first time my son is seeing and relishing these little wonders which we have been watching and ignoring in our routine life!” The couple had no words to reply and felt sorry for their remarks. Moral of the story: “ “don’t judge a book by its cover”. is this the moral fits the story or provide me some moral for this story :)

  Read the article

< Previous Page | 19 20 21 22 23 24 25 26 27 28 29  | Next Page >