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  • How to change the install path of my Linux Source tree?

    - by Sen
    I was trying to bring up my custom kernel. I did the following : make menuconfig && make modules && make modules_install && make install I would like to change the install PATH. How can i do that? I tried doing export INSTALL_PATH=<my custom path> But then it is only creating the vmlinux.bin(it is not creating the ramdisk image!!) But if i am not doing that, make install will automatically create the ramdisk image in the default /boot folder. How can i change that?? Thanks, Sen

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  • Can I make Puppet's module-to-file mapping to start searching at the top of the modules tree?

    - by John Siracusa
    Consider these two Puppet module files: # File modules/a/manifests/b/c.pp class a::b::c { include b::c } # File modules/b/manifests/c.pp class b::c { notify { "In b::c": } } It seems that when Puppet hits the include b::c directive in class a::b::c, it searches for the corresponding *.pp file by looking backwards from the current class and decides that it find the correct file located at ../../b/c.pp. In other words, it resolves b::c to the same *.pp file that the include b::c statement appears in: modules/a/manifests/b/c.pp I expected it (and would like it) to instead find and load the file modules/b/manifests/c.pp. Is there a way to make Puppet do this? If not, it seems to me that module names may not contain any other module names anywhere within them, which is a pretty surprising restriction.

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  • How can I automatically synchronize a directory tree on multiple machines?

    - by Blacklight Shining
    I have two Mac laptops and a Debian server, each with a directory that I would like to keep in sync between the three. The solution should meet the following criteria (in rough order of importance): It must not use any third-party service (e.g. Dropbox, SugarSync, Google whatever). This does not include installing additional software (as long as it's free). It must not require me to use specific directories or change my way of storing things. (Dropbox does this IIRC) It must work in all directions (changes made on /any/ machine should be pushed to the others) All data sent must be encrypted (I have ssh keypairs set up already) It must work even when not all machines are available (changes should be pushed to a machine when it comes back online) It must work even when the /directories/ on some machines are not available (they may be stored on disk images which will not always be mounted) This can be solved for Macs by using launchd to automatically launch and kill (or in some way change the behavior of) whatever daemon is used for syncing when the images are mounted and unmounted. It must be immediate (using an event-based system, not a periodic one like cron) It must be flexible (if more machines are added, I should be able to incorporate them easily) I also have some preferences that I would like to be fulfilled, but do not have to be: It should notify me somehow if there are conflicts or other errors. It should recognize symbolic and hard links and create corresponding ones. It should allow me to create a list of exceptions (subdirectories which will not be synced at all). It should not require me to set up port forwarding or otherwise reconfigure a network. This can be solved by using an ssh tunnel with reverse port forwarding. If you have a solution that meets some, but not all of the criteria, please contribute it in the comments as it might be useful in some way, and it might be possible to meet some of the criteria separately. What I tried, and why it didn't work: rsync and lsyncd do not support bidirectional synchronization csync2 is designed for server clusters and does not appear to work with machines with dynamic IPs DRBD (suggested by amotzg) involves installing a kernel module and does not appear to work on systems running OS X

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  • Beaglebone Black running Debian, does device tree overlay act as an api?

    - by user3953989
    This maybe more of a Linux specific question but... I've been reading many tutorials and it seems that you can use JavaScript, Python, and C++ to write code for the Beaglebone Black(BBB). It looks like the way C++ interfaces with the BBB hardware is via reading/writing text files on the OS while Python has it's own library. All the C++ examples out there control the GPIO and PWM via reading/writing to text files. Is this the only way to access the hardware or just how Linux does drivers?

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  • What is the proper query to get all the children in a tree?

    - by Nathan Adams
    Lets say I have the following MySQL structure: CREATE TABLE `domains` ( `id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, `domain` CHAR(50) NOT NULL, `parent` INT(11) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=MYISAM AUTO_INCREMENT=10 DEFAULT CHARSET=latin1 insert into `domains`(`id`,`domain`,`parent`) values (1,'.com',0); insert into `domains`(`id`,`domain`,`parent`) values (2,'example.com',1); insert into `domains`(`id`,`domain`,`parent`) values (3,'sub1.example.com',2); insert into `domains`(`id`,`domain`,`parent`) values (4,'sub2.example.com',2); insert into `domains`(`id`,`domain`,`parent`) values (5,'s1.sub1.example.com',3); insert into `domains`(`id`,`domain`,`parent`) values (6,'s2.sub1.example.com',3); insert into `domains`(`id`,`domain`,`parent`) values (7,'sx1.s1.sub1.example.com',5); insert into `domains`(`id`,`domain`,`parent`) values (8,'sx2.s2.sub1.example.com',6); insert into `domains`(`id`,`domain`,`parent`) values (9,'x.sub2.example.com',4); In my mind that is enough to emulate a simple tree structure: .com | example / \ sub1 sub2 ect My problem is that give sub1.example.com I want to know all the children of sub1.example.com without using multiple queries in my code. I have tried joining the table to itself and tried to use subqueries, I can't think of anything that will reveal all the children. At work we are using MPTT to keep in hierarchal order a list of domains/subdomains however, I feel that there is an easier way to do it. I did some digging and someone did something similar but they required the use of a function in MySQL. I don't think for something simple like this we would need a whole function. Maybe I am just dumb and not seeing some sort of obvious solution. Also, feel free to alter the structure.

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  • Is there any way to access files in your source tree in Android?

    - by Chris Thompson
    Hi all, This is a bit unorthodox but I'm trying to figure out if there's a way to access files stored in the src tree of my applications apk in Android. I'm trying to use i-Jetty (Jetty implementation for Android) and rather than use it as a separate application and manually download my war file, I'd rather just bake i-jetty in. However, in order to use (easily) standard html/jsp I need to be able to give it a document root, preferably within my application's apk file. I know Android specifically works to prevent you from accessing (freely) the stuff on the actual system so this may not be possible, but I'm thinking it might be possible to access something within the apk. One option to work around this would be to have all of the files stored in the res directory and then copy them to the sdcard on startup but this wouldn't allow me to automatically remove the files on uninstall. To give you an idea of what I've tried, currently, the html files are stored in org.webtext.android Context rootContext = new Context(server_, "/", Context.SESSIONS); rootContext.setResourceBase("org/webtext/webapp"); Returns a 404 error. final URL url = this.getClassLoader().getResource("org/webtext/webapp"); Context html = new WebAppContext(url.toExternalForm(), "/"); Blows up with a NullPointerException because no URL is returned from the getResource call. Any thoughts would be greatly appreciated! Thanks, Chris

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  • Is a red-black tree my ideal data structure?

    - by Hugo van der Sanden
    I have a collection of items (big rationals) that I'll be processing. In each case, processing will consist of removing the smallest item in the collection, doing some work, and then adding 0-2 new items (which will always be larger than the removed item). The collection will be initialised with one item, and work will continue until it is empty. I'm not sure what size the collection is likely to reach, but I'd expect in the range 1M-100M items. I will not need to locate any item other than the smallest. I'm currently planning to use a red-black tree, possibly tweaked to keep a pointer to the smallest item. However I've never used one before, and I'm unsure whether my pattern of use fits its characteristics well. 1) Is there a danger the pattern of deletion from the left + random insertion will affect performance, eg by requiring a significantly higher number of rotations than random deletion would? Or will delete and insert operations still be O(log n) with this pattern of use? 2) Would some other data structure give me better performance, either because of the deletion pattern or taking advantage of the fact I only ever need to find the smallest item? Update: glad I asked, the binary heap is clearly a better solution for this case, and as promised turned out to be very easy to implement. Hugo

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  • Implementation question involving implementing an interface

    - by Vivin Paliath
    I'm writing a set of collection classes for different types of Trees. I'm doing this as a learning exercise and I'm also hoping it turns out to be something useful. I really want to do this the right way and so I've been reading Effective Java and I've also been looking at the way Joshua Bloch implemented the collection classes by looking at the source. I seem to have a fair idea of what is being done, but I still have a few things to sort out. I have a Node<T> interface and an AbstractNode<T> class that implements the Node interface. I then created a GenericNode<T> (a node that can have 0 to n children, and that is part of an n-ary tree) class that extends AbstractNode<T> and implements Node<T>. This part was easy. Next, I created a Tree<T> interface and an AbstractTree<T> class that implements the Tree<T> interface. After that, I started writing a GenericTree<T> class that extends AbstractTree<T> and implements Tree<T>. This is where I started having problems. As far as the design is concerned, a GenericTree<T> can only consist of nodes of type GenericTreeNode<T>. This includes the root. In my Tree<T> interface I have: public interface Tree<T> { void setRoot(Node<T> root); Node<T> getRoot(); List<Node<T>> postOrder(); ... rest omitted ... } And, AbstractTree<T> implements this interface: public abstract class AbstractTree<T> implements Tree<T> { protected Node<T> root; protected AbstractTree() { } protected AbstractTree(Node<T> root) { this.root = root; } public void setRoot(Node<T> root) { this.root = root; } public Node<T> getRoot() { return this.root; } ... rest omitted ... } In GenericTree<T>, I can have: public GenericTree(Node<T> root) { super(root); } But what this means is that you can create a generic tree using any subtype of Node<T>. You can also set the root of a tree to any subtype of Node<T>. I want to be able to restrict the type of the node to the type of the tree that it can represent. To fix this, I can do this: public GenericTree(GenericNode<T> root) { super(root); } However, setRoot still accepts a parameter of type Node<T>. Which means a user can still create a tree with the wrong type of root node. How do I enforce this constraint? The only way I can think of doing is either: Do an instanceof which limits the check to runtime. I'm not a huge fan of this. Remove setRoot from the interface and have the base class implement this method. This means that it is not part of the contract and anyone who wants to make a new type of tree needs to remember to implement this method. Is there a better way? The second question I have concerns the return type of postOrder which is List<Node<T>>. This means that if a user is operating on a GenericTree<T> object and calls postOrder, he or she receives a list that consists of Node<T> objects. This means when iterating through (using a foreach construct) they would have perform an explicit cast to GenericNode<T> if they want to use methods that are only defined in that class. I don't like having to place this burden on the user. What are my options in this case? I can only think of removing the method from the interface and have the subclass implement this method making sure that it returns a list of appropriate subtype of Node<T>. However, this once again removes it from the contract and it's anyone who wants to create a new type of tree has to remember to implement this method. Is there a better way?

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  • Why boost property tree write_json saves everything as string? Is it possible to change that?

    - by pprzemek
    I'm trying to serialize using boost property tree write_json, it saves everything as strings, it's not that data are wrong, but I need to cast them explicitly every time and I want to use them somewhere else. (like in python or other C++ json (non boost) library) here is some sample code and what I get depending on locale: boost::property_tree::ptree root, arr, elem1, elem2; elem1.put<int>("key0", 0); elem1.put<bool>("key1", true); elem2.put<float>("key2", 2.2f); elem2.put<double>("key3", 3.3); arr.push_back( std::make_pair("", elem1) ); arr.push_back( std::make_pair("", elem2) ); root.put_child("path1.path2", arr); std::stringstream ss; write_json(ss, root); std::string my_string_to_send_somewhare_else = ss.str(); and my_string_to_send_somewhere_else is sth. like this: { "path1" : { "path2" : [ { "key0" : "0", "key1" : "true" }, { "key2" : "2.2", "key3" : "3.3" } ] } } Is there anyway to save them as the values, like: "key1" : true or "key2" : 2.2 ?

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  • How can I SETF an element in a tree by an accessor?

    - by Willi Ballenthin
    We've been using Lisp in my AI course. The assignments I've received have involved searching and generating tree-like structures. For each assignment, I've ended up writing something like: (defun initial-state () (list 0 ; score nil ; children 0 ; value 0)) ; something else and building my functions around these "states", which are really just nested lists with some loosely defined structure. To make the structure more rigid, I've tried to write accessors, such as: (defun state-score ( state ) (nth 2 state)) This works for reading the value (which should be all I need to do in a nicely functional world. However, as time crunches, and I start to madly hack, sometimes I want a mutable structure). I don't seem to be able to SETF the returned ...thing (place? value? pointer?). I get an error with something like: (setf (state-score *state*) 10) Sometimes I seem to have a little more luck writing the accessor/mutator as a macro: (defmacro state-score ( state ) `(nth 2 ,state)) However I don't know why this should be a macro, so I certainly shouldn't write it as a macro (except that sometimes it works. Programming by coincidence is bad). What is an appropriate strategy to build up such structures? More importantly, where can I learn about whats going on here (what operations affect the memory in what way)?

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  • Which templating languages output HTML *as a tree of nodes*?

    - by alamar
    HTML is a tree of nodes, before all. It's not just a text. However, most templating engines handle their input and output as it was just a text; they don't care what happens around their tags, their {$foo}'s and <% bar() %>'s; also they don't care about what are they outputting. Sometimes they happen to produce a correct html, but that's just a coincidence; they didn't aim for that, all they wanted is to replace some funny marks in the text stream with their evaluation. There are a few templating engines which do treat their output as a set of nodes; XSLT and Haml come to mind. For some tasks, this has advantages: for example, you can automatically reformat (like, delete all empty text nodes; auto-indent; word-wrap). The result is guaranteed to be a correct xml/sgml unless you use a strict subset of operations that can break that. Also, such templating engine would automatically quote strings, differently in text nodes and in attributes, because it strictly knows whether you're writing an attribute or a text node. Moreover, it can conditionally remove a node from output because it knows where it does begin and end, which is useful, and do other non-trivial node operations. You might not like XSLT for its verbosiness or functionalness, but it's damn helps that your template is xmllint-able XML, and your output is a good sgml/xml. So the question is: Which template engines do you know that treat their output as a set of correct nodes, not just an unstructured text? I know XSLT, Haml and some obscure python-based one. Moar!

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  • How do I add an object to a binary tree based on the value of a member variable?

    - by Max
    How can I get a specific value from an object? I'm trying to get a value of an instance for eg. ListOfPpl newListOfPpl = new ListOfPpl(id, name, age); Object item = newListOfPpl; How can I get a value of name from an Object item?? Even if it is easy or does not interest you can anyone help me?? Edited: I was trying to build a binary tree contains the node of ListOfPpl, and need to sort it in the lexicographic. Here's my code for insertion on the node. Any clue?? public void insert(Object item){ Node current = root; Node follow = null; if(!isEmpty()){ root = new Node(item, null, null); return; }boolean left = false, right = false; while(current != null){ follow = current; left = false; right = false; //I need to compare and sort it if(item.compareTo(current.getFighter()) < 0){ current = current.getLeft(); left = true; }else { current = current.getRight(); right = true; } }if(left) follow.setLeft(new Node(item, null, null)); else follow.setRight(new Node(item, null, null)); }

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  • EF code first error "The specified index already exists. [ IX_Id ]" for object tree

    - by PascalN
    Using EF code first 4.3 I'm trying to model an object tree with a required-required relationships and a required-optional relationships. Here is a simple representation of those classes public class Top { public int Id { get; set; } public virtual Middle Middle { get; set; } } public class Middle { public int Id { get; set; } public virtual Child Child { get; set; } } public class Child { public int Id { get; set; } } Here is the OnModelCreating code modelBuilder.Entity<Top>().HasRequired(t => t.Middle).WithRequiredPrincipal().WillCascadeOnDelete(); modelBuilder.Entity<Middle>().HasRequired(t => t.Child).WithOptional().WillCascadeOnDelete(); This produces the error "The specified index already exists. [ IX_Id ]" on SQLCE After checking the db schema, both model binder fluent API configuration lines create an index IX_Id on the table Middles. Does anyone know how to work around that problem? Is there a way to set the index name? Thank you! Pascal

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  • Is this Leftist Tree piece of code from Wikipedia correct?

    - by they changed my name
    Link public Node merge(Node x, Node y) { if(x == null) return y; if(y == null) return x; // if this was a max height biased leftist tree, then the // next line would be: if(x.element < y.element) if(x.element.compareTo(y.element) > 0) { // x.element > y.element Node temp = x; x = y; y = temp; } x.rightChild = merge(x.rightChild, y); if(x.leftChild == null) { // left child doesn't exist, so move right child to the left side x.leftChild = x.rightChild; x.rightChild = null; x.s = 1; } else { // left child does exist, so compare s-values if(x.leftChild.s < x.rightChild.s) { Node temp = x.leftChild; x.leftChild = x.rightChild; x.rightChild = temp; } // since we know the right child has the lower s-value, we can just // add one to its s-value x.s = x.rightChild.s + 1; } return x; } What makes me ask this question is: if(x.element.compareTo(y.element) > 0) { // x.element > y.element Node temp = x; x = y; y = temp; } Isn't that just not gonna work, since the references are only switched inside the method?

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  • How do I code a tree of objects in Haskell with pointers to parent and children?

    - by axilmar
    I've got the following problem: I have a tree of objects of different classes where an action in the child class invalidates the parent. In imperative languages, it is trivial to do. For example, in Java: public class A { private List<B> m_children = new LinkedList<B>(); private boolean m_valid = true; public void invalidate() { m_valid = false; } public void addChild(B child) { m_children.add(child); child.m_parent = this; } } public class B { public A m_parent = null; private int m_data = 0; public void setData(int data) { m_data = 0; m_parent.invalidate(); } } public class Main { public static void main(String[] args) { A a = new A(); B b = new B(); b.setData(0); //invalidates A } } How do I do the above in Haskell? I cannot wrap my mind around this, since once I construct an object in Haskell, it cannot be changed. I would be much obliged if the relevant Haskell code is posted.

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  • 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?

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  • Dynamically loading sub-trees into YUI Treeview

    - by user319399
    When you create a YUI TreeView instance, you can pass in an object that represents an entire tree, and it will automatically build up the TextNodes for you. I'd like to send in a partial tree, such that the tree only goes, say, 2 levels deep, and anything deeper than that will invoke dynamic loading. I've got that much working. Now for the interesting part. In the dynamic loading callback I give to my tree instance, I want to again be able to just give YUI a big object representing more of the tree. I want to do something like this: // data is a array of objects organized into a tree, with some nodes requiring dynamic loading when they are navigated to tree = new YAHOO.widget.TreeView("treeDiv1", data); tree.setDynamicLoad(loadDataForNode); function loadDataForNode(node, onCompleteCallback) { if(node.children.length==0) { var subTree = { "label":"Cars", isLeaf:false, children:[ { "label":"Chevy", isLeaf:true }, { "label":"Ford", isLeaf:true }, ] }; // doesn't work, even though it has the required "label" field var tempNode = new YAHOO.widget.TextNode(subTree, node, true); } onCompleteCallback(); } Is this possible? Or do I have to iterate over all the nodes in my subtree and construct individual TextNodes for each one? Thanks much...

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  • How to define trees with more than one type in ML programing language

    - by user550413
    Well, I am asked to do the next thing: To define a binary tree which can contain 2 different types: ('a,'b) abtree and these are the requirements: Any inner vertex (not a leaf) must be of the type 'a or 'b and the leafs have no value. For every path in the tree all 'a values must appear before the 'b value: examples of paths: 'a->'a->'a-'b (legal) 'a->'b->'b (legal) 'a->'a->'a (legal) 'b->'b->'b (legal) 'a->'b->'a (ILLEGAL) and also I need to define another tree which is like the one described above but now I have got also 'c and in the second requirement it says that for every path I 'a values appear before the 'b values and all the 'b values appear before the 'c values. First, I am not sure how to define binary trees to have more than 1 type in them. I mean the simplest binary tree is: datatype 'a tree = leaf | br of 'a * 'a tree * 'a tree; And also how I can define a tree to have these requirements. Any help will be appreciated. Thanks.

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  • Applying a function to a custom type in F#

    - by Frederik Wordenskjold
    On my journey to learning F#, I've run into a problem I cant solve. I have defined a custom type: type BinTree = | Node of int * BinTree * BinTree | Empty I have made a function which takes a tree, traverses it, and adds the elements it visits to a list, and returns it: let rec inOrder tree = seq{ match tree with | Node (data, left, right) -> yield! inOrder left yield data; yield! inOrder right | Empty -> () } |> Seq.to_list; Now I want to create a function, similar to this, which takes a tree and a function, traverses it and applies a function to each node, then returns the tree: mapInOrder : ('a -> 'b) -> 'a BinTree -> 'b BinTree This seems easy, and it probably is! But I'm not sure how to return the tree. I've tried this: let rec mapInOrder f tree = match tree with | Node(data, left, right) -> mapInOrder f left Node(f(data), left, right) mapInOrder f right | Empty -> () but this returns a unit. I havent worked with custom types before, so I'm probably missing something there!

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  • How does Haskell do pattern matching without us defining an Eq on our data types?

    - by devoured elysium
    I have defined a binary tree: data Tree = Null | Node Tree Int Tree and have implemented a function that'll yield the sum of the values of all its nodes: sumOfValues :: Tree -> Int sumOfValues Null = 0 sumOfValues (Node Null v Null) = v sumOfValues (Node Null v t2) = v + (sumOfValues t2) sumOfValues (Node t1 v Null) = v + (sumOfValues t1) sumOfValues (Node t1 v t2) = v + (sumOfValues t1) + (sumOfValues t2) It works as expected. I had the idea of also trying to implement it using guards: sumOfValues2 :: Tree -> Int sumOfValues2 Null = 0 sumOfValues2 (Node t1 v t2) | t1 == Null && t2 == Null = v | t1 == Null = v + (sumOfValues2 t2) | t2 == Null = v + (sumOfValues2 t1) | otherwise = v + (sumOfValues2 t1) + (sumOfValues2 t2) but this one doesn't work because I haven't implemented Eq, I believe: No instance for (Eq Tree) arising from a use of `==' at zzz3.hs:13:3-12 Possible fix: add an instance declaration for (Eq Tree) In the first argument of `(&&)', namely `t1 == Null' In the expression: t1 == Null && t2 == Null In a stmt of a pattern guard for the definition of `sumOfValues2': t1 == Null && t2 == Null The question that has to be made, then, is how can Haskell make pattern matching without knowing when a passed argument matches, without resorting to Eq?

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  • Java ORM related question - SQL Vs Google DB (Big Table?) GAE

    - by StackerFlow
    I was wondering about the following two options when one is not using SQL tables but ORM based DBs (Example - when you are using GAE) Would the second option be less efficient? Requirement: There is an object. The object has a collection of similar items. I need to store this object. Example, say the object is a tree and it has a collection of leaves. Option 1: Traditional SQL type structure: Table for the Tree (with TreeId as the identifier for a row in the Table.) Table for the Leaves (where each leaf has a TreeId and to show the leaves of a tree, I query all leaves where the TreeId is the Id of the tree.) Here, the Tree structure DOES NOT have a field with leaves. Option 2: ORM / GAE Tables: Using the same example above, I have an object for Tree where the object has a collection (Set/List in Java/C++) of leaves. I store and retrieve the Tree together with the leaves (as the leaves are implemented as a Set in the Tree object) My question is, will the second one be less efficient that the first option? If so, why? Are there other alternatives? Thank you!

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  • how to change a while sql query loop into an array loop

    - by Mac Taylor
    hey guys i record number of queries of my website and in page the below script runs , 40 extra queries added to page . how can I change this sql connection into a propper and light one function tree_set($index) { //global $menu; Remove this. $q=mysql_query("select id,name,parent from cats where parent='$index'"); if(mysql_num_rows($q) === 0) { return; } // User $tree instead of the $menu global as this way there shouldn't be any data duplication $tree = $index > 0 ? '<ul>' : ''; // If we are on index 0 then we don't need the enclosing ul while($arr=mysql_fetch_assoc($q)) { $subFileCount=mysql_query("select id,name,parent from cats where parent='{$arr['id']}'"); if(mysql_num_rows($subFileCount) > 0) { $class = 'folder'; } else { $class = 'file'; } $tree .= '<li>'; $tree .= '<span class="'.$class.'">'.$arr['name'].'</span>'; $tree .=tree_set("".$arr['id'].""); $tree .= '</li>'."\n"; } $tree .= $index > 0 ? '</ul>' : ''; // If we are on index 0 then we don't need the enclosing ul return $tree; } i heard , this can be done by changing it into an array , but i don't know how to do so thanks in advance

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  • Doing XML extracts with XSLT without having to read the whole DOM tree into memory?

    - by Thorbjørn Ravn Andersen
    I have a situation where I want to extract some information from some very large but regular XML files (just had to do it with a 500 Mb file), and where XSLT would be perfect. Unfortunately those XSLT implementations I am aware of (except the most expensive version of Saxon) does not support only having the necessary part of the DOM read in but reads in the whole tree. This cause the computer to swap to death. The XPath in question is //m/e[contains(.,'foobar') so it is essentially just a grep. Is there an XSLT implementation which can do this? Or an XSLT implementation which given suitable "advice" can do this trick of pruning away the parts in memory which will not be needed again? I'd prefer a Java implementation but both Windows and Linux are viable native platforms. EDIT: The input XML looks like: <log> <!-- Fri Jun 26 12:09:27 CEST 2009 --> <e h='12:09:27,284' l='org.apache.catalina.session.ManagerBase' z='1246010967284' t='ContainerBackgroundProcessor[StandardEngine[Catalina]]' v='10000'> <m>Registering Catalina:type=Manager,path=/axsWHSweb-20090626,host=localhost</m></e> <e h='12:09:27,284' l='org.apache.catalina.session.ManagerBase' z='1246010967284' t='ContainerBackgroundProcessor[StandardEngine[Catalina]]' v='10000'> <m>Force random number initialization starting</m></e> <e h='12:09:27,284' l='org.apache.catalina.session.ManagerBase' z='1246010967284' t='ContainerBackgroundProcessor[StandardEngine[Catalina]]' v='10000'> <m>Getting message digest component for algorithm MD5</m></e> <e h='12:09:27,284' l='org.apache.catalina.session.ManagerBase' z='1246010967284' t='ContainerBackgroundProcessor[StandardEngine[Catalina]]' v='10000'> <m>Completed getting message digest component</m></e> <e h='12:09:27,284' l='org.apache.catalina.session.ManagerBase' z='1246010967284' t='ContainerBackgroundProcessor[StandardEngine[Catalina]]' v='10000'> <m>getDigest() 0</m></e> ...... </log> Essentialy I want to select some m-nodes (and I know the XPath is wrong for that, it was just a quick hack), but maintain the XML layout. EDIT: It appears that STX may be what I am looking for (I can live with another transformation language), and that Joost is an implementation hereof. Any experiences? EDIT: I found that Saxon 6.5.4 with -Xmx1500m could load my XML, so this allowed me to use my XPaths right now. This is just a lucky stroke so I'd still like to solve this generically - this means scriptable which in turn means no handcrafted Java filtering first. EDIT: Oh, by the way. This is a log file very similar to what is generated by the log4j XMLLayout. The reason for XML is to be able to do exactly this, namely do queries on the log. This is the initial try, hence the simple question. Later I'd like to be able to ask more complex questions - therefore I'd like the query language to be able to handle the input file.

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  • WPF TreeView MouseDown

    - by imekon
    I've got something like this in a TreeView: <DataTemplate x:Key="myTemplate"> <StackPanel MouseDown="OnItemMouseDown"> ... </StackPanel> </DataTemplate> Using this I get the mouse down events if I click on items in the stack panel. However... there seems to be another item behind the stack panel that is the TreeViewItem - it's very hard to hit, but not impossible, and that's when the problems start to occur. I had a go at handling PreviewMouseDown on TreeViewItem, however that seems to require e.Handled = false otherwise standard tree view behaviour stops working. Ok, Here's the source code... MainWindow.xaml <Window x:Class="WPFMultiSelectTree.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WPFMultiSelectTree" Title="Multiple Selection Tree" Height="300" Width="300"> <Window.Resources> <!-- Declare the classes that convert bool to Visibility --> <local:VisibilityConverter x:Key="visibilityConverter"/> <local:VisibilityInverter x:Key="visibilityInverter"/> <!-- Set the style for any tree view item --> <Style TargetType="TreeViewItem"> <Style.Triggers> <DataTrigger Binding="{Binding Selected}" Value="True"> <Setter Property="Background" Value="DarkBlue"/> <Setter Property="Foreground" Value="White"/> </DataTrigger> </Style.Triggers> <EventSetter Event="PreviewMouseDown" Handler="OnTreePreviewMouseDown"/> </Style> <!-- Declare a hierarchical data template for the tree view items --> <HierarchicalDataTemplate x:Key="RecursiveTemplate" ItemsSource="{Binding Children}"> <StackPanel Margin="2" Orientation="Horizontal" MouseDown="OnTreeMouseDown"> <Ellipse Width="12" Height="12" Fill="Green"/> <TextBlock Margin="2" Text="{Binding Name}" Visibility="{Binding Editing, Converter={StaticResource visibilityInverter}}"/> <TextBox Margin="2" Text="{Binding Name}" KeyDown="OnTextBoxKeyDown" IsVisibleChanged="OnTextBoxIsVisibleChanged" Visibility="{Binding Editing, Converter={StaticResource visibilityConverter}}"/> <TextBlock Margin="2" Text="{Binding Index, StringFormat=({0})}"/> </StackPanel> </HierarchicalDataTemplate> <!-- Declare a simple template for a list box --> <DataTemplate x:Key="ListTemplate"> <TextBlock Text="{Binding Name}"/> </DataTemplate> </Window.Resources> <Grid> <!-- Declare the rows in this grid --> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition/> <RowDefinition Height="Auto"/> <RowDefinition/> </Grid.RowDefinitions> <!-- The first header --> <TextBlock Grid.Row="0" Margin="5" Background="PowderBlue">Multiple selection tree view</TextBlock> <!-- The tree view --> <TreeView Name="m_tree" Margin="2" Grid.Row="1" ItemsSource="{Binding Children}" ItemTemplate="{StaticResource RecursiveTemplate}"/> <!-- The second header --> <TextBlock Grid.Row="2" Margin="5" Background="PowderBlue">The currently selected items in the tree</TextBlock> <!-- The list box --> <ListBox Name="m_list" Margin="2" Grid.Row="3" ItemsSource="{Binding .}" ItemTemplate="{StaticResource ListTemplate}"/> </Grid> </Window> MainWindow.xaml.cs /// <summary> /// Interaction logic for MainWindow.xaml /// </summary> public partial class MainWindow : Window { private Container m_root; private Container m_first; private ObservableCollection<Container> m_selection; private string m_current; /// <summary> /// Constructor /// </summary> public MainWindow() { InitializeComponent(); m_selection = new ObservableCollection<Container>(); m_root = new Container("root"); for (int parents = 0; parents < 50; parents++) { Container parent = new Container(String.Format("parent{0}", parents + 1)); for (int children = 0; children < 1000; children++) { parent.Add(new Container(String.Format("child{0}", children + 1))); } m_root.Add(parent); } m_tree.DataContext = m_root; m_list.DataContext = m_selection; m_first = null; } /// <summary> /// Has the shift key been pressed? /// </summary> private bool ShiftPressed { get { return Keyboard.IsKeyDown(Key.LeftShift) || Keyboard.IsKeyDown(Key.RightShift); } } /// <summary> /// Has the control key been pressed? /// </summary> private bool CtrlPressed { get { return Keyboard.IsKeyDown(Key.LeftCtrl) || Keyboard.IsKeyDown(Key.RightCtrl); } } /// <summary> /// Clear down the selection list /// </summary> private void DeselectAndClear() { foreach(Container container in m_selection) { container.Selected = false; } m_selection.Clear(); } /// <summary> /// Add the container to the list (if not already present), /// mark as selected /// </summary> /// <param name="container"></param> private void AddToSelection(Container container) { if (container == null) { return; } foreach (Container child in m_selection) { if (child == container) { return; } } container.Selected = true; m_selection.Add(container); } /// <summary> /// Remove container from list, mark as not selected /// </summary> /// <param name="container"></param> private void RemoveFromSelection(Container container) { m_selection.Remove(container); container.Selected = false; } /// <summary> /// Process single click on a tree item /// /// Normally just select an item /// /// SHIFT-Click extends selection /// CTRL-Click toggles a selection /// </summary> /// <param name="sender"></param> private void OnTreeSingleClick(object sender) { FrameworkElement element = sender as FrameworkElement; if (element != null) { Container container = element.DataContext as Container; if (container != null) { if (CtrlPressed) { if (container.Selected) { RemoveFromSelection(container); } else { AddToSelection(container); } } else if (ShiftPressed) { if (container.Parent == m_first.Parent) { if (container.Index < m_first.Index) { Container item = container; for (int i = container.Index; i < m_first.Index; i++) { AddToSelection(item); item = item.Next; if (item == null) { break; } } } else if (container.Index > m_first.Index) { Container item = m_first; for (int i = m_first.Index; i <= container.Index; i++) { AddToSelection(item); item = item.Next; if (item == null) { break; } } } } } else { DeselectAndClear(); m_first = container; AddToSelection(container); } } } } /// <summary> /// Process double click on tree item /// </summary> /// <param name="sender"></param> private void OnTreeDoubleClick(object sender) { FrameworkElement element = sender as FrameworkElement; if (element != null) { Container container = element.DataContext as Container; if (container != null) { container.Editing = true; m_current = container.Name; } } } /// <summary> /// Clicked on the stack panel in the tree view /// /// Double left click: /// /// Switch to editing mode (flips visibility of textblock and textbox) /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void OnTreeMouseDown(object sender, MouseButtonEventArgs e) { Debug.WriteLine("StackPanel mouse down"); switch(e.ChangedButton) { case MouseButton.Left: switch (e.ClickCount) { case 2: OnTreeDoubleClick(sender); e.Handled = true; break; } break; } } /// <summary> /// Clicked on tree view item in tree /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void OnTreePreviewMouseDown(object sender, MouseButtonEventArgs e) { Debug.WriteLine("TreeViewItem preview mouse down"); switch (e.ChangedButton) { case MouseButton.Left: switch (e.ClickCount) { case 1: { // We've had a single click on a tree view item // Unfortunately this is the WHOLE tree item, including the +/- // symbol to the left. The tree doesn't do a selection, so we // have to filter this out... MouseDevice device = e.Device as MouseDevice; Debug.WriteLine(String.Format("Tree item clicked on: {0}", device.DirectlyOver.GetType().ToString())); // This is bad. The whole point of WPF is for the code // not to know what the UI has - yet here we are testing for // it as a workaround. Sigh... if (device.DirectlyOver.GetType() != typeof(Path)) { OnTreeSingleClick(sender); } // Cannot say handled - if we do it stops the tree working! //e.Handled = true; } break; } break; } } /// <summary> /// Key press in text box /// /// Return key finishes editing /// Escape key finishes editing, restores original value (this doesn't work!) /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void OnTextBoxKeyDown(object sender, KeyEventArgs e) { switch(e.Key) { case Key.Return: { TextBox box = sender as TextBox; if (box != null) { Container container = box.DataContext as Container; if (container != null) { container.Editing = false; e.Handled = true; } } } break; case Key.Escape: { TextBox box = sender as TextBox; if (box != null) { Container container = box.DataContext as Container; if (container != null) { container.Editing = false; container.Name = m_current; e.Handled = true; } } } break; } } /// <summary> /// When text box becomes visible, grab focus and select all text in it. /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void OnTextBoxIsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e) { bool visible = (bool)e.NewValue; if (visible) { TextBox box = sender as TextBox; if (box != null) { box.Focus(); box.SelectAll(); } } } } Here's the Container class public class Container : INotifyPropertyChanged { private string m_name; private ObservableCollection<Container> m_children; private Container m_parent; private bool m_selected; private bool m_editing; /// <summary> /// Constructor /// </summary> /// <param name="name">name of object</param> public Container(string name) { m_name = name; m_children = new ObservableCollection<Container>(); m_parent = null; m_selected = false; m_editing = false; } /// <summary> /// Name of object /// </summary> public string Name { get { return m_name; } set { if (m_name != value) { m_name = value; OnPropertyChanged("Name"); } } } /// <summary> /// Index of object in parent's children /// /// If there's no parent, the index is -1 /// </summary> public int Index { get { if (m_parent != null) { return m_parent.Children.IndexOf(this); } return -1; } } /// <summary> /// Get the next item, assuming this is parented /// /// Returns null if end of list reached, or no parent /// </summary> public Container Next { get { if (m_parent != null) { int index = Index + 1; if (index < m_parent.Children.Count) { return m_parent.Children[index]; } } return null; } } /// <summary> /// List of children /// </summary> public ObservableCollection<Container> Children { get { return m_children; } } /// <summary> /// Selected status /// </summary> public bool Selected { get { return m_selected; } set { if (m_selected != value) { m_selected = value; OnPropertyChanged("Selected"); } } } /// <summary> /// Editing status /// </summary> public bool Editing { get { return m_editing; } set { if (m_editing != value) { m_editing = value; OnPropertyChanged("Editing"); } } } /// <summary> /// Parent of this object /// </summary> public Container Parent { get { return m_parent; } set { m_parent = value; } } /// <summary> /// WPF Property Changed event /// </summary> public event PropertyChangedEventHandler PropertyChanged; /// <summary> /// Handler to inform WPF that a property has changed /// </summary> /// <param name="name"></param> private void OnPropertyChanged(string name) { if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(name)); } } /// <summary> /// Add a child to this container /// </summary> /// <param name="child"></param> public void Add(Container child) { m_children.Add(child); child.m_parent = this; } /// <summary> /// Remove a child from this container /// </summary> /// <param name="child"></param> public void Remove(Container child) { m_children.Remove(child); child.m_parent = null; } } The two classes VisibilityConverter and VisibilityInverter are implementations of IValueConverter that translates bool to Visibility. They make sure the TextBlock is displayed when not editing, and the TextBox is displayed when editing.

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