Search Results

Search found 11597 results on 464 pages for 'complete graph'.

Page 44/464 | < Previous Page | 40 41 42 43 44 45 46 47 48 49 50 51  | Next Page >

  • Creating transparent gridlines

    - by Rob Penridge
    I'm trying to get the chart's gridlines to be transparent but it doesn't seem to be supported: http://support.sas.com/documentation/cdl/en/grstatug/63302/HTML/default/viewer.htm#n1f71f6e9v037an1jy274v66z4r1.htm I'm doing to try and blend the gridlines with the chart background color (which in my code can change between colors) which would make the gridlines subtle rather than jarring when background colors change. Here is my code: ** ** TAKE THE DEFAULT STYLE BEING USED. MODIFY IT SO THAT ** GRAPH GRIDLINES WILL BE GREEN AND MOSTLY TRANSPARENT *; proc template; define style my_style; parent = styles.default; style GraphGridLines from GraphGridLines / contrastcolor=green transparency=.05; end; run; ** ** LAYOUT TEMPLATE FOR A SIMPLE SERIES CHART *; proc template; define statgraph mychart; begingraph; layout overlay / wallcolor=black xaxisopts=(display=(line) griddisplay=on) yaxisopts=(display=(line)) ; seriesplot x=name y=height / lineattrs=(color=white); endlayout; endgraph; end; run; ** ** PLOT SAMPLE DATA USING CUSTOM STYLE AND CHART LAYOUT WE JUST DEFINED *; ods graphics / width=640 height=640 ; ods html style=my_style; proc sgrender data=sashelp.class template=mychart; run; ods html close; Is there another way to achieve this effect by blending the green color with the background color?

    Read the article

  • Getting a "for each" loop in Java to run in different order everytime

    - by R Stokes
    Hi, Basically my problem is that I'm trying to write a method that finds a random path in a graph of strings, which takes as it's parameters a start string, an integer length and a Vector of strings that will store the path. I'm attempting to do this by first adding the starting string to our blank vector, recursing through its neighbors until the vector's length (not including the start node) is the same as the integer length specified in the parameters. I've provided my code so far here: public Vector<String> findRandomPathFrom(String n, int len, Vector<String> randomPath){ randomPath.add(n); if (randomPath.size() == len + 1) return randomPath; for (String m : this.neighbours(n)){ if (!randomPath.contains(m) && findRandomPathFrom(m, len, randomPath) != null) return randomPath; } path.setSize(path.size() - 1); return null; } It seems to be working fine, returning a path with exactly the number of strings specified after the given start string. However, for any given starting string it generates the EXACT same path everytime, which kind of defeats the purpose of it being a random path generator. I'm guessing this problem is related to my "for each" loop, which loops through all the neighbouring strings of your current string. It seems to just be going with the first string in the neighbours vector every single time. Can anyone help me fix this problem so that it will choose a random neighbour instead of going in order? tl;dr - Any way of getting a "for each" loop in java to process a collection in a random order as oppoosed to start-to-finsih? Thanks in advance

    Read the article

  • Facebook Page Statuses API

    - by Simon R
    I've got a curl function in php which posts a status update to our facebook page. However, when I post the update it makes the status appear from me personally rather than me the group. Does anyone know how you can post as administrator of the group. The script is as follows; $xPost['access_token'] = "[key]" $xPost['message'] = "Posting a message test."; $query = http_build_query($xPost); $ch = curl_init('https://graph.facebook.com/broadland/feed'); curl_setopt($ch, CURLOPT_VERBOSE, 1); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_HEADER, 1); curl_setopt($ch, CURLOPT_TIMEOUT, 120); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_POSTFIELDS, $query); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 1); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0); curl_setopt($ch, CURLOPT_CAINFO, NULL); curl_setopt($ch, CURLOPT_CAPATH, NULL); curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 0); $result = curl_exec($ch);

    Read the article

  • drawing graphs in php

    - by user434885
    i am using php to generate graphs from arrays. I wish to create multiple graphs on the same page as i need to design a summary report from answers extracted from a database. Currently i am using this code and am only able to get one single graph. what additions to the code do i need to make to get multiple graphs? <?php function draw_graph($values) { // Get the total number of columns we are going to plot $columns = count($values); // Get the height and width of the final image $width = 300; $height = 200; // Set the amount of space between each column $padding = 5; // Get the width of 1 column $column_width = $width / $columns ; // Generate the image variables $im = imagecreate($width,$height); $gray = imagecolorallocate ($im,0xcc,0xcc,0xcc); $gray_lite = imagecolorallocate ($im,0xee,0xee,0xee); $gray_dark = imagecolorallocate ($im,0x7f,0x7f,0x7f); $white = imagecolorallocate ($im,0xff,0xff,0xff); // Fill in the background of the image imagefilledrectangle($im,0,0,$width,$height,$white); $maxv = 0; // Calculate the maximum value we are going to plot for($i=0;$i<$columns;$i++)$maxv = max($values[$i],$maxv); // Now plot each column for($i=0;$i<$columns;$i++) { $column_height = ($height / 100) * (( $values[$i] / $maxv) *100); $x1 = $i*$column_width; $y1 = $height-$column_height; $x2 = (($i+1)*$column_width)-$padding; $y2 = $height; imagefilledrectangle($im,$x1,$y1,$x2,$y2,$gray_dark); } header ("Content-type: image/png"); imagepng($im); imagedestroy($im); } $values = array("23","32","35","57","12"); $values2 = array("123","232","335","157","102"); draw_graph($values2); draw_graph($values);//no output is coming draw_graph($values2);//no output is coming draw_graph($values);//no output is coming ?>

    Read the article

  • Is there a free tool which can help visualize the logic of a stored procedure in SQL Server 2008 R2?

    - by Hamish Grubijan
    I would like to be able to plot a call graph of a stored procedure. I am not interested in every detail, and I am not concerned with dynamic SQL (although it would be cool to detect it and skip it maybe or mark it as such.) I would like the tool to generate a tree for me, given the server name, db name, stored proc name, a "call tree", which includes: Parent stored procedure. Every other stored procedure that is being called as a child of the caller. Every table that is being modified (updated or deleted from) as a child of the stored proc which does it. Hopefully it is clear what I am after; if not - please do ask. If there is not a tool that can do this, then I would like to try to write one myself. Python 2.6 is my language of choice, and I would like to use standard libraries as much as possible. Any suggestions? EDIT: For the purposes of bounty Warning: SQL syntax is COMPLEX. I need something that can parse all kinds of SQL 2008, even if it looks stupid. No corner cases barred :) EDIT2: I would be OK if all I am missing is graphics.

    Read the article

  • Facebook API - Detect if session is active OR NOT active

    - by Tom Doe
    I'm sure I'm simply overlooking something in the Facebook API docs. Basically, after I've loaded the FB Graph, I need to know if the session is active... I cannot simply assume they're logged out and simply re-render if they're logged in once the 'auth.statusChange' event is triggered. I need to know right off the bat. Below is the code that I've used. Most importantly the FB.getLoginStatus/getAuthResponse/getAccessToken don't work like I'd expect; essentially where it indicates, when invoked, whether they're logged in or out. (function(d) { // Create fb-root var fb_root = document.createElement('div'); fb_root.id = "fb-root"; document.getElementsByTagName('body')[0].appendChild( fb_root ); // Load FB Async var js, id = 'facebook-jssdk', ref = d.getElementsByTagName('script')[0]; if (d.getElementById(id)) {return;} js = d.createElement('script'); js.id = id; js.async = true; js.src = "//connect.facebook.net/en_US/all.js"; ref.parentNode.insertBefore(js, ref); // App config-data var config = { appId : XXXX, cookie: true, status: true, frictionlessRequests: true }; window.fbAsyncInit = function() { // This won't work. // I can't assume they're logged out and rely on this to tell me they're logged in. FB.Event.subscribe('auth.statusChange', function(response) {}); // Init FB.init(config); // These do not inidicate if the user is logged out :( FB.getLoginStatus(function(response) { }); FB.getAuthResponse(function(response) { }); FB.getAccessToken(function(response) { }); }; }(document)); Any help is much appreciated. :)

    Read the article

  • Is there a phrase or word to describe an algorithim or programme is complete in that given any value for its arguments there is a predictable outcome?

    - by Mrk Mnl
    Is there a phrase to describe an algorithim or programme is complete in that given any possible value for its arguments there is a predicatable outcome? i.e. all the ramifications have been considered whatever the context? A simple example would be the below function: function returns string get_item_type(int type_no) { if(type_no < 10) return "hockey stick" else if (type_no < 20) return "bulldozer" else return "unknown" } (excuse the dismal pseudo code) No matter what number is supplied all possibiblites are catered for. My question is: is there a word to fill the blank here: "get_item_type() is ______ complete" ? (The answer is not Turing Complete - that is something quite different - but I annoyingly always think of something as "Turing Complete" when I am thinking of the above).

    Read the article

  • Is there a phrase or word to describe an algorithim or program is complete in that given any value for its arguments there is a defined outcome?

    - by Mrk Mnl
    Is there a phrase or word to describe an algorithim or programme is complete in that given any value for its arguments there is a defined outcome? i.e. all the ramifications have been considered whatever the context? A simple example would be the below function: function returns string get_item_type(int type_no) { if(type_no < 10) return "hockey stick" else if (type_no < 20) return "bulldozer" else return "unknown" } (excuse the dismal pseudo code) No matter what number is supplied all possibiblites are catered for. My question is: is there a word to fill the blank here: "get_item_type() is ______ complete" ? (The answer is not Turing Complete - that is something quite different - but I annoyingly always think of something as "Turing Complete" when I am thinking of the above).

    Read the article

  • Traveling Salesman in polynomial time

    - by Andres
    Problem Description: Write a program in any language with the shortest number of characters that solves the following problem: Given a collection of cities and the cost of travel between each pair of them, find the cheapest way of visiting all of the cities and returning to your starting point. All solutions must take at most polynomial time. Input will be in the form of a text file named simply "i". The text file will contain data in the following format: city1# city2# cost$ cityA# cityB# cost$ ... Each element in the file is separated with a space, and there is a newline at the end of every line. Code count does not include whitespace. Solutions that take longer than polynomial time to find will not be accepted

    Read the article

  • How to work with this turing machine?

    - by Lazer
    This is a screenshot of the applet LogiCell 1.0, link to which I found here. As the bottom left corner shows, this is doing sum 0+1 and the result is 01b (bottom right hand side). I am not able to link what is displayed to what the inputs ans outputs are. For example in this case - seeing the snapshot, how do you determine that the inputs are 0 and 1 and the output is 01?

    Read the article

  • why cacti is showing empty graph.??.even if rrd file created..

    - by Divya mohan Singh
    hii, i have develop my own snmp service..and i want to plot a graph of an OID provided. so, i have create graph in cacti. -) Its is showing device up. -) It is creating rrd file.(RRDTool says OK). -) showing the graph but its empty. but when i check it say rrdtool fetch AVERAGE it showing me all the values nan only..the monitored OID is having value 47 and i have set min=0 and max=100 i am using cacti appliance by rpath http://www.rpath.org/ui/#/appliances?id=http://www.rpath.org/api/products/cacti-appliance still i can show value on graph.. where is the problem??can anyone plz tell me??

    Read the article

  • wpf do animation until background worker finishes its work

    - by toni
    Hi! I have an application that do some hard stuff when user clicks a start button and takes a long time. During this I would like to do some animation over a label, for example, changing opacity from 0 to 1 and vice versa and change foreground color between several colors at the same time changing opacity. I want it stops doing animation when background worker finishes its work. How can I do this? and how can I start animation and stop it from c#? Thanks very much!

    Read the article

  • Rails auto_complete "undefined method `auto_complete_for'" problem

    - by Andrew Wize
    rails - 2.3.8 ruby - 1.8.7 After auto_complete plugin installstion i still have "undefined method `auto_complete_for'" problem! Andrey-Bezruks-MacBook-Pro:eyeonasia.stage wizeflux$ ruby script/plugin install http://github.com/rails/auto_complete.git --force svn: '/Users/wizeflux/Projects/ionasia/eyeonasia.stage/vendor/plugins' is not a working copy Initialized empty Git repository in /Users/wizeflux/Projects/ionasia/eyeonasia.stage/vendor/plugins/auto_complete/.git/ warning: Option "depth" is ignored for github.com/rails/auto_complete.git From github.com/rails/auto_complete * branch HEAD - FETCH_HEAD Andrey-Bezruks-MacBook-Pro:eyeonasia.stage wizeflux$ after restarting server i get an error on line " auto_complete_for :listings, :name " - undefined method `auto_complete_for' for #

    Read the article

  • Flex datagrid - determining when grid has completed renderering?

    - by ccdugga
    hi, i have a datagrid which contains a number of itemrenderers, it is populated each time a user does a search. Is there an event which can tell me when the datagrid has completed rendering all new rows and item renderers? I need to trigger an event once everything has been created so that i can resize then container which holds the grid. Currently im using DataGridEvent.HEADER_RELEASE and CollectionEvent.COLLECTION_CHANGE events to manage this however the problem with these events is that they get called as each new row is being added to the datagrid. therefore the whole process is becoming sluggish. Does anyone have any suggestions?

    Read the article

  • how can I save/keep-in-sync an in-memory graph of objects with the database?

    - by Greg
    Question - What is a good best practice approach for how can I save/keep-in-sync an jn-memory graph of objects with the database? Background: That is say I have the classes Node and Relationship, and the application is building up a graph of related objects using these classes. There might be 1000 nodes with various relationships between them. The application needs to query the structure hence an in-memory approach is good for performance no doubt (e.g. traverse the graph from Node X to find the root parents) The graph does need to be persisted however into a database with tables NODES and RELATIONSHIPS. Therefore what is a good best practice approach for how can I save/keep-in-sync an jn-memory graph of objects with the database? Ideal requirements would include: build up changes in-memory and then 'save' afterwards (mandatory) when saving, apply updates to database in correct order to avoid hitting any database constraints (mandatory) keep persistence mechanism separate from model, for ease in changing persistence layer if needed, e.g. don't just wrap an ADO.net DataRow in the Node and Relationship classes (desirable) mechanism for doing optimistic locking (desirable) Or is the overhead of all this for a smallish application just not worth it and I should just hit the database each time for everything? (assuming the response times were acceptable) [would still like to avoid if not too much extra overhead to remain somewhat scalable re performance]

    Read the article

  • What makes people think that NNs have more computational power than existing models?

    - by Bubba88
    I've read in Wikipedia that neural-network functions defined on a field of arbitrary real/rational numbers (along with algorithmic schemas, and the speculative `transrecursive' models) have more computational power than the computers we use today. Of course it was a page of russian wikipedia (ru.wikipedia.org) and that may be not properly proven, but that's not the only source of such.. rumors Now, the thing that I really do not understand is: How can a string-rewriting machine (NNs are exactly string-rewriting machines just as Turing machines are; only programming language is different) be more powerful than a universally capable U-machine? Yes, the descriptive instrument is really different, but the fact is that any function of such class can be (easily or not) turned to be a legal Turing-machine. Am I wrong? Do I miss something important? What is the cause of people saying that? I do know that the fenomenum of undecidability is widely accepted today (though not consistently proven according to what I've read), but I do not really see a smallest chance of NNs being able to solve that particular problem. Add-in: Not consistently proven according to what I've read - I meant that you might want to take a look at A. Zenkin's (russian mathematician) papers after mid-90-s where he persuasively postulates the wrongness of G. Cantor's concepts, including transfinite sets, uncountable sets, diagonalization method (method used in the proof of undecidability by Turing) and maybe others. Even Goedel's incompletness theorems were proven in right way in only 21-st century.. That's all just to plug Zenkin's work to the post cause I don't know how widespread that knowledge is in CS community so forgive me if that did look stupid. Thank you!

    Read the article

  • flash cs4 file reference. Event.COMPLETE not called on a MAC,

    - by jobbie jones
    Hi, I am working with a fileReference, however I'm having issues running on Safari on a MAC... EDIT The below example also doesnt work on Safari on a MAC... http://www.permadi.com/blog/2010/06/flash-as3-using-filereference-to-load-files-example-for-flash-cs4-and-above/ # The workflow on a PC runs as such: 1) Create file reference 2) attach addEventListener's for Event.SELECT and Event.COMPLETE 3) call the browse() method On a PC, Event.SELECT is fired when a file has been selected. Event.COMPLETE is fired when the file data is available to flash. If I select an 500meg file, it takes a few seconds before Event.COMPLETE is fired. If I attempt to access the file data properties (such as reading the data stream) before Event.COMPLETE is fired, I receive null reference errors... So far so good. However, on a MAC (speficially Safari, not tested other browsers), the Event.COMPLETE is not fired. I have checked the Adobe docs, which say Event.COMPLETE is fired when the upload is completed. So why does it get fired on windows when the fileReference has parsed the file, but the upload method has not yet been called... Can anyone help? Here's snippets of the code I am working on: public function browseFile(target:Object):void { var imagesFilter:FileFilter = new FileFilter("Allowed files", "*.jpg;*.bmp;*.flv;"); fileReference.browse([imagesFilter]); fileReference.addEventListener(Event.SELECT, fileSelect); fileReference.addEventListener(Event.COMPLETE, fileSelectComplete); } private function fileSelect(event:Event):void { // update label - IMPORTANT for large files as there's a delay while flash parses file, before control is handed back to this script... setStatusLabel("...loading file"); var fileReference:FileReference = event.target as FileReference; fileReference.addEventListener(Event.COMPLETE, fileSelectComplete); // load the file into the fileReference object fileReference.load(); } // Called when upload file has been processed by flash (a few secs for large files, or fileRef.data is null...) private function fileSelectComplete(event:Event):void { var fileReference:FileReference=event.target as FileReference; trace("ready to do things - but not fired on Safari on a MAC "); }

    Read the article

  • How can I make a core-plot graph on the phone that doesn't auto-expand to fill the whole superview

    - by Robb
    I'm pretty sure I saw an example where the graph wasn't filling the whole iPhone screen, but I can't get that to happen in my app, nor in the Core-Plot Test app from Switch On The Code. I've added a subview to the original CPLayerHostingView in the sample, then changed the classes – original back to UIView, new subview to CPLayerHostingView, and I've reconnected the File's owner's view outlet to the new subview. When I create a graph with: graph = [[CPXYGraph alloc] initWithFrame: theSubviewOutlet.bounds]; … and step through the first stages of building up the layers the bounds are accurate (i.e. the same as in the .xib) however, when all the initialization is done, and the graph shows up, it fills the whole superview. Am I missing something obvious?

    Read the article

  • Optimizing a Parking Lot Problem. What algorithims should I use to fit the most amount of cars in th

    - by Adam Gent
    What algorithms (brute force or not) would I use to put in as many cars (assume all cars are the same size) in a parking lot so that there is at least one exit (from the container) and a car cannot be blocked. Or can someone show me an example of this problem solved programmatically. The parking lot varies in shape would be nice but if you want to assume its some invariant shape that is fine. Another Edit: Assume that driving distance in the parking lot is not a factor (although it would be totally awesome if it was weighted factor to number of cars in lot). Another Edit: Assume 2 Dimensional (no cranes or driving over cars). Another Edit: You cannot move cars around once they are parked (its not a valet parking lot). I hope the question is specific enough now.

    Read the article

  • Creating a computer with pencil and paper [closed]

    - by Justian Meyer
    This concept has been brought to my attention before, but many people might know it from this popular comic here, where he uses stones instead of points on a paper. This concept is so abstract to me. A full-functioning computer that can manage algorithms, input, output, etc. without electricity? Surely, it's difficult to visualize because my definition of a computer is not exactly what the word sounds like COMPUTE-ER. Can someone help me bring the concept to light - the understanding, how to make one, etc? It seems like it'd be an interesting read, although I think I wouldn't be able to make it do anything. Many thanks in advance for responses. I've tried searching Google, but all I got were ways to diagram code and chart ideas. -.Justian.

    Read the article

  • Prevent recursive CTE visiting nodes multiple times

    - by bacar
    Consider the following simple DAG: 1->2->3->4 And a table, #bar, describing this (I'm using SQL Server 2005): parent_id child_id 1 2 2 3 3 4 //... other edges, not connected to the subgraph above Now imagine that I have some other arbitrary criteria that select the first and last edges, i.e. 1-2 and 3-4. I want to use these to find the rest of my graph. I can write a recursive CTE as follows (I'm using terminology from MSDN): with foo(parent_id,child_id) as ( // anchor member that happens to select first and last edges: select parent_id,child_id from #bar where parent_id in (1,3) union all // recursive member: select #bar.* from #bar join foo on #bar.parent_id = foo.child_id ) select parent_id,child_id from foo However, this results in edge 3-4 being selected twice: parent_id child_id 1 2 3 4 2 3 3 4 // 2nd appearance! How can I prevent the query from recursing into subgraphs that have already been described? I could achieve this if, in my "recursive member" part of the query, I could reference all data that has been retrieved by the recursive CTE so far (and supply a predicate indicating in the recursive member excluding nodes already visited). However, I think I can access data that was returned by the last iteration of the recursive member only. This will not scale well when there is a lot of such repetition. Is there a way of preventing this unnecessary additional recursion? Note that I could use "select distinct" in the last line of my statement to achieve the desired results, but this seems to be applied after all the (repeated) recursion is done, so I don't think this is an ideal solution. Edit - hainstech suggests stopping recursion by adding a predicate to exclude recursing down paths that were explicitly in the starting set, i.e. recurse only where foo.child_id not in (1,3). That works for the case above only because it simple - all the repeated sections begin within the anchor set of nodes. It doesn't solve the general case where they may not be. e.g., consider adding edges 1-4 and 4-5 to the above set. Edge 4-5 will be captured twice, even with the suggested predicate. :(

    Read the article

  • Problem on a Floyd-Warshall implementation using c++

    - by Henrique
    I've got a assignment for my college, already implemented Dijkstra and Bellman-Ford sucessfully, but i'm on trouble on this one. Everything looks fine, but it's not giving me the correct answer. Here's the code: void FloydWarshall() { //Also assume that n is the number of vertices and edgeCost(i,i) = 0 int path[500][500]; /* A 2-dimensional matrix. At each step in the algorithm, path[i][j] is the shortest path from i to j using intermediate vertices (1..k-1). Each path[i][j] is initialized to edgeCost(i,j) or infinity if there is no edge between i and j. */ for(int i = 0 ; i <= nvertices ; i++) for(int j = 0 ; j <= nvertices ; j++) path[i][j] = INFINITY; for(int j = 0 ; j < narestas ; j++) //narestas = number of edges { path[arestas[j]->v1][arestas[j]->v2] = arestas[j]->peso; //peso = weight of the edge (aresta = edge) path[arestas[j]->v2][arestas[j]->v1] = arestas[j]->peso; } for(int i = 0 ; i <= nvertices ; i++) //path(i, i) = 0 path[i][i] = 0; //test print, it's working fine //printf("\n\n\nResultado FloydWarshall:\n"); //for(int i = 1 ; i <= nvertices ; i++) // printf("distancia ao vertice %d: %d\n", i, path[1][i]); //heres the problem, it messes up, and even a edge who costs 4, and the minimum is 4, it prints 2. //for k = 1 to n for(int k = 1 ; k <= nvertices ; k++) //for i = 1 to n for(int i = 1 ; i <= nvertices ; i++) //for j := 1 to n for(int j = 1 ; j <= nvertices ; j++) if(path[i][j] > path[i][k] + path[k][j]) path[i][j] = path[i][k] + path[k][j]; printf("\n\n\nResultado FloydWarshall:\n"); for(int i = 1 ; i <= nvertices ; i++) printf("distancia ao vertice %d: %d\n", i, path[1][i]); } im using this graph example i've made: 6 7 1 2 4 1 5 1 2 3 1 2 5 2 5 6 3 6 4 6 3 4 2 means we have 6 vertices (1 to 6), and 7 edges (1,2) with weight 4... etc.. If anyone need more info, i'm up to giving it, just tired of looking at this code and not finding an error.

    Read the article

  • Is there a way to make PHP's SplHeap recalculate? (aka: add up-heap to SplHeap?)

    - by md2k7
    I am using an SplHeap to hold graph nodes of a tree with directed edges that will be traversed from the leaves to the root. For this, I precalculate the "fan-in" of nodes and put them into the heap so that I can always retrieve the node with the smallest fan-in (0) from it. After visiting a node, I reduce the fan-in of its successor by 1. Then obviously, the heap needs to be recalculated because the successor is now in the wrong place there. I have tried recoverFromCorruption(), but it doesn't do anything and keeps the heap in the wrong order (node with larger fanIn stays in front of smaller fanIn). As a workaround, I'm now creating a new heap after each visit, amounting to a full O(N*log(N)) sort each time. It should be possible, however, to make up-heap operations on the changed heap entry until it's in the right position in O(log(N)). The API for SplHeap doesn't mention an up-heap (or deletion of an arbitrary element - it could then be re-added). Can I somehow derive a class from SplHeap to do this or do I have to create a pure PHP heap from scratch? EDIT: Code example: class VoteGraph { private $nodes = array(); private function calculateFanIn() { /* ... */ } // ... private function calculateWeights() { $this->calculateFanIn(); $fnodes = new GraphNodeHeap(); // heap by fan-in ascending (leaves are first) foreach($this->nodes as $n) { // omitted: filter loops $fnodes->insert($n); } // traversal from leaves to root while($fnodes->valid()) { $node = $fnodes->extract(); // fetch a leaf from the heap $successor = $this->nodes[$node->successor]; // omitted: actual job of traversal $successor->fanIn--; // will need to fix heap (sift up successor) because of this //$fnodes->recoverFromCorruption(); // doesn't work for what I want // workaround: rebuild $fnodes from scratch $fixedHeap = new GraphNodeHeap(); foreach($fnodes as $e) $fixedHeap->insert($e); $fnodes = $fixedHeap; } } } class GraphNodeHeap extends SplHeap { public function compare($a, $b) { if($a->fanIn === $b->fanIn) return 0; else return $a->fanIn < $b->fanIn ? 1 : -1; } }

    Read the article

< Previous Page | 40 41 42 43 44 45 46 47 48 49 50 51  | Next Page >