Search Results

Search found 34513 results on 1381 pages for 'end task'.

Page 280/1381 | < Previous Page | 276 277 278 279 280 281 282 283 284 285 286 287  | Next Page >

  • Latex newenvironment

    - by Alex
    There's something wrong with this code: \newenvironment{Tbl} {\begin{tabularx}{\textwidth}{|l|X|} \hline} {\end{tabularx}} but this is fine: \newenvironment{Tbl} {\begin{tabular}{|l|l|} \hline} {\end{tabular}} Why? And how can I get the first to work?

    Read the article

  • How to limit JTextArea max Rows and Coloums?

    - by Billbo bug
    I am using JTextArea in JScrollPane I want to limit the maximum number of lines possible and the maximum chars in each line. I need that the string will be exactly like on the screen, each line will end with '\n' (if there another line after it) and the user will be able to insert only X lines and Y chars in each line. I tried to limit the lines but i don't know exactly how many lines do i have because of the line wrapping, The line wrapping is starting new line visualy on the screen(because of the width of the JTextArea) but in the string of the component it is really the same line with no '\n' to indicate new line. I do not have an idea how to limit the max chars in each line while typing. There are 2 stages: The typing of the string- keep that the user will not be able to type more then X lines and Y chars in each line. (even if the line wrap only visualy or the user typed '/n') Insert the string to the DB- after cliking 'OK' convert the string that every line will end with "/n" even if the user did not typed it and the line was wrapped only visualy. There are few problems if i will count the chars in the line and insert '/n' in the end of the line, thats why i decided to do it in two stages. In the first stage ehile the user is typing i would rather only limit it visualy and force line wrpping or something similar. Only in the second stage when i save string i will add the '/n' even if the user did not typed it in the end of the lines! Does anyone have an idea? I know that i will have to use DocumentFilter OR StyledDocument. Here is sample code that limit only the lines to 3:(but not the chars in row to 19) private JTextArea textArea ; textArea = new JTextArea(3,19); textArea .setLineWrap(true); textArea .setDocument(new LimitedStyledDocument(3)); JScrollPane scrollPane = new JScrollPane(textArea public class LimitedStyledDocument extends DefaultStyledDocument /** Field maxCharacters */ int maxLines; public LimitedStyledDocument(int maxLines) { maxCharacters = maxLines; } public void insertString(int offs, String str, AttributeSet attribute) throws BadLocationException { Element root = this.getDefaultRootElement(); int lineCount = getLineCount(str); if (lineCount + root.getElementCount() <= maxLines){ super.insertString(offs, str, attribute); } else { Toolkit.getDefaultToolkit().beep(); } } /** * get Line Count * * @param str * @return the count of '\n' in the String */ private int getLineCount(String str){ String tempStr = new String(str); int index; int lineCount = 0; while (tempStr.length() > 0){ index = tempStr.indexOf("\n"); if(index != -1){ lineCount++; tempStr = tempStr.substring(index+1); } else{ break; } } return lineCount; } }

    Read the article

  • Rails AtomFeedBuilder Entry :Url option appears in url tag but not in link tag

    - by Nick
    Hello, I'm using the AtomFeedHelper and everything is working fine except for one feed where I need to link each entry to a URL which is not the default polymorphic_url for the record. Per the documentation I've specified an :url option for the entry. This correctly renders a <url> tag in the atom node but the <link rel="alternate" still points to the default polymorphic_url. Looking at the source and the documentation I don't understand why this is happening. Here's an example builder: atom_feed do |feed| feed.title("Reports") feed.updated(@reports.first.created_at) for report in @reports content = report.notes feed.entry(report) do |entry| entry.title(report.title) entry.content(content, :type => 'html') entry.url("http://myhost/page/") entry.updated(report.updated_at.strftime("%Y-%m-%dT%H:%M:%SZ")) entry.author do |author| author.name(report.user.username) end end end end Here's an example of a problem node: <entry> <id>tag:molly.recargo.com,2005:SiteReport/2</id> <published>2010-03-30T13:11:07-07:00</published> <updated>2010-03-30T13:11:07-07:00</updated> <link rel="alternate" type="text/html" href="http://myhost/site_reports/2"/> <title>Test Title</title> <content type="html">Test Content</content> <url>http://myhost/page/</url> <updated>2010-03-30T13:11:07Z</updated> <author> <name>Author</name> </author> </entry> I wan the href value in the link tag to match the value in the url tag but it does not. When I look at the source listed for entry here http://api.rubyonrails.org/classes/ActionView/Helpers/AtomFeedHelper/AtomFeedBuilder.html I'd assume that this line would work correctly: @xml.link(:rel => 'alternate', :type => 'text/html', :href => options[:url] || @view.polymorphic_url(record)) Confused. Has anyone encountered this before? Thanks all!

    Read the article

  • Hangs with LINQ-SQL Server and TransactionScope

    - by Zian Choy
    I'm encountering a hang when the program tries to access the fruit database. I've already enabled network access MSDTC on both my development computer and the SQL Server server. Code: (pardon the code coloring...SO's misinterpreting my VB .NET) Using ts As New TransactionScope Dim fruit As New FruitDataContext Dim thingies As New ThingiesDataContext If (From f In fruit.tblApples Where f.Rotten = True).Count >= 1 Then 'Record today's date as the day that the rotten apples were dumped. End If 'Other complicated code that uses ThingiesDataContext and FruitDataContext du.SubmitChanges() ts.Complete() End Using

    Read the article

  • What's wrong with this MySQL Stored Function?

    - by Matt
    Having trouble getting this to apply in MySQL Workbench 5.2.15 DELIMITER // CREATE DEFINER=`potts`@`%` FUNCTION `potts`.`fn_create_category_test` (test_arg VARCHAR(50)) RETURNS int BEGIN DECLARE new_id int; SET new_id = 8; RETURN new_id; END// The actual function will have a lot more between BEGIN and END but as it stands, even this 3 liner won't work. Thanks!

    Read the article

  • How rspec works with rails3 for integration-tests?

    - by makevoid
    What I'm trying to ahieve is to do integration tests with webrat in rails3 like Yehuda does with test-unit in http://pivotallabs.com/talks/76-extending-rails-3 minute 34. an example: describe SomeApp it "should show the index page" visit "/" body.should =~ /hello world/ end end Does someone knows a way to do it?

    Read the article

  • Java code optimization on matrix windowing computes in more time

    - by rano
    I have a matrix which represents an image and I need to cycle over each pixel and for each one of those I have to compute the sum of all its neighbors, ie the pixels that belong to a window of radius rad centered on the pixel. I came up with three alternatives: The simplest way, the one that recomputes the window for each pixel The more optimized way that uses a queue to store the sums of the window columns and cycling through the columns of the matrix updates this queue by adding a new element and removing the oldes The even more optimized way that does not need to recompute the queue for each row but incrementally adjusts a previously saved one I implemented them in c++ using a queue for the second method and a combination of deques for the third (I need to iterate through their elements without destructing them) and scored their times to see if there was an actual improvement. it appears that the third method is indeed faster. Then I tried to port the code to Java (and I must admit that I'm not very comfortable with it). I used ArrayDeque for the second method and LinkedLists for the third resulting in the third being inefficient in time. Here is the simplest method in C++ (I'm not posting the java version since it is almost identical): void normalWindowing(int mat[][MAX], int cols, int rows, int rad){ int i, j; int h = 0; for (i = 0; i < rows; ++i) { for (j = 0; j < cols; j++) { h = 0; for (int ry =- rad; ry <= rad; ry++) { int y = i + ry; if (y >= 0 && y < rows) { for (int rx =- rad; rx <= rad; rx++) { int x = j + rx; if (x >= 0 && x < cols) { h += mat[y][x]; } } } } } } } Here is the second method (the one optimized through columns) in C++: void opt1Windowing(int mat[][MAX], int cols, int rows, int rad){ int i, j, h, y, col; queue<int>* q = NULL; for (i = 0; i < rows; ++i) { if (q != NULL) delete(q); q = new queue<int>(); h = 0; for (int rx = 0; rx <= rad; rx++) { if (rx < cols) { int mem = 0; for (int ry =- rad; ry <= rad; ry++) { y = i + ry; if (y >= 0 && y < rows) { mem += mat[y][rx]; } } q->push(mem); h += mem; } } for (j = 1; j < cols; j++) { col = j + rad; if (j - rad > 0) { h -= q->front(); q->pop(); } if (j + rad < cols) { int mem = 0; for (int ry =- rad; ry <= rad; ry++) { y = i + ry; if (y >= 0 && y < rows) { mem += mat[y][col]; } } q->push(mem); h += mem; } } } } And here is the Java version: public static void opt1Windowing(int [][] mat, int rad){ int i, j = 0, h, y, col; int cols = mat[0].length; int rows = mat.length; ArrayDeque<Integer> q = null; for (i = 0; i < rows; ++i) { q = new ArrayDeque<Integer>(); h = 0; for (int rx = 0; rx <= rad; rx++) { if (rx < cols) { int mem = 0; for (int ry =- rad; ry <= rad; ry++) { y = i + ry; if (y >= 0 && y < rows) { mem += mat[y][rx]; } } q.addLast(mem); h += mem; } } j = 0; for (j = 1; j < cols; j++) { col = j + rad; if (j - rad > 0) { h -= q.peekFirst(); q.pop(); } if (j + rad < cols) { int mem = 0; for (int ry =- rad; ry <= rad; ry++) { y = i + ry; if (y >= 0 && y < rows) { mem += mat[y][col]; } } q.addLast(mem); h += mem; } } } } I recognize this post will be a wall of text. Here is the third method in C++: void opt2Windowing(int mat[][MAX], int cols, int rows, int rad){ int i = 0; int j = 0; int h = 0; int hh = 0; deque< deque<int> *> * M = new deque< deque<int> *>(); for (int ry = 0; ry <= rad; ry++) { if (ry < rows) { deque<int> * q = new deque<int>(); M->push_back(q); for (int rx = 0; rx <= rad; rx++) { if (rx < cols) { int val = mat[ry][rx]; q->push_back(val); h += val; } } } } deque<int> * C = new deque<int>(M->front()->size()); deque<int> * Q = new deque<int>(M->front()->size()); deque<int> * R = new deque<int>(M->size()); deque< deque<int> *>::iterator mit; deque< deque<int> *>::iterator mstart = M->begin(); deque< deque<int> *>::iterator mend = M->end(); deque<int>::iterator rit; deque<int>::iterator rstart = R->begin(); deque<int>::iterator rend = R->end(); deque<int>::iterator cit; deque<int>::iterator cstart = C->begin(); deque<int>::iterator cend = C->end(); for (mit = mstart, rit = rstart; mit != mend, rit != rend; ++mit, ++rit) { deque<int>::iterator pit; deque<int>::iterator pstart = (* mit)->begin(); deque<int>::iterator pend = (* mit)->end(); for(cit = cstart, pit = pstart; cit != cend && pit != pend; ++cit, ++pit) { (* cit) += (* pit); (* rit) += (* pit); } } for (i = 0; i < rows; ++i) { j = 0; if (i - rad > 0) { deque<int>::iterator cit; deque<int>::iterator cstart = C->begin(); deque<int>::iterator cend = C->end(); deque<int>::iterator pit; deque<int>::iterator pstart = (M->front())->begin(); deque<int>::iterator pend = (M->front())->end(); for(cit = cstart, pit = pstart; cit != cend; ++cit, ++pit) { (* cit) -= (* pit); } deque<int> * k = M->front(); M->pop_front(); delete k; h -= R->front(); R->pop_front(); } int row = i + rad; if (row < rows && i > 0) { deque<int> * newQ = new deque<int>(); M->push_back(newQ); deque<int>::iterator cit; deque<int>::iterator cstart = C->begin(); deque<int>::iterator cend = C->end(); int rx; int tot = 0; for (rx = 0, cit = cstart; rx <= rad; rx++, ++cit) { if (rx < cols) { int val = mat[row][rx]; newQ->push_back(val); (* cit) += val; tot += val; } } R->push_back(tot); h += tot; } hh = h; copy(C->begin(), C->end(), Q->begin()); for (j = 1; j < cols; j++) { int col = j + rad; if (j - rad > 0) { hh -= Q->front(); Q->pop_front(); } if (j + rad < cols) { int val = 0; for (int ry =- rad; ry <= rad; ry++) { int y = i + ry; if (y >= 0 && y < rows) { val += mat[y][col]; } } hh += val; Q->push_back(val); } } } } And finally its Java version: public static void opt2Windowing(int [][] mat, int rad){ int cols = mat[0].length; int rows = mat.length; int i = 0; int j = 0; int h = 0; int hh = 0; LinkedList<LinkedList<Integer>> M = new LinkedList<LinkedList<Integer>>(); for (int ry = 0; ry <= rad; ry++) { if (ry < rows) { LinkedList<Integer> q = new LinkedList<Integer>(); M.addLast(q); for (int rx = 0; rx <= rad; rx++) { if (rx < cols) { int val = mat[ry][rx]; q.addLast(val); h += val; } } } } int firstSize = M.getFirst().size(); int mSize = M.size(); LinkedList<Integer> C = new LinkedList<Integer>(); LinkedList<Integer> Q = null; LinkedList<Integer> R = new LinkedList<Integer>(); for (int k = 0; k < firstSize; k++) { C.add(0); } for (int k = 0; k < mSize; k++) { R.add(0); } ListIterator<LinkedList<Integer>> mit; ListIterator<Integer> rit; ListIterator<Integer> cit; ListIterator<Integer> pit; for (mit = M.listIterator(), rit = R.listIterator(); mit.hasNext();) { Integer r = rit.next(); int rsum = 0; for (cit = C.listIterator(), pit = (mit.next()).listIterator(); cit.hasNext();) { Integer c = cit.next(); Integer p = pit.next(); rsum += p; cit.set(c + p); } rit.set(r + rsum); } for (i = 0; i < rows; ++i) { j = 0; if (i - rad > 0) { for(cit = C.listIterator(), pit = M.getFirst().listIterator(); cit.hasNext();) { Integer c = cit.next(); Integer p = pit.next(); cit.set(c - p); } M.removeFirst(); h -= R.getFirst(); R.removeFirst(); } int row = i + rad; if (row < rows && i > 0) { LinkedList<Integer> newQ = new LinkedList<Integer>(); M.addLast(newQ); int rx; int tot = 0; for (rx = 0, cit = C.listIterator(); rx <= rad; rx++) { if (rx < cols) { Integer c = cit.next(); int val = mat[row][rx]; newQ.addLast(val); cit.set(c + val); tot += val; } } R.addLast(tot); h += tot; } hh = h; Q = new LinkedList<Integer>(); Q.addAll(C); for (j = 1; j < cols; j++) { int col = j + rad; if (j - rad > 0) { hh -= Q.getFirst(); Q.pop(); } if (j + rad < cols) { int val = 0; for (int ry =- rad; ry <= rad; ry++) { int y = i + ry; if (y >= 0 && y < rows) { val += mat[y][col]; } } hh += val; Q.addLast(val); } } } } I guess that most is due to the poor choice of the LinkedList in Java and to the lack of an efficient (not shallow) copy method between two LinkedList. How can I improve the third Java method? Am I doing some conceptual error? As always, any criticisms is welcome. UPDATE Even if it does not solve the issue, using ArrayLists, as being suggested, instead of LinkedList improves the third method. The second one performs still better (but when the number of rows and columns of the matrix is lower than 300 and the window radius is small the first unoptimized method is the fastest in Java)

    Read the article

  • rails paperclip unable to access image from another view

    - by curiousCoder
    my app has an habtm relation b/w listings and categories. now from the categories index page, a user filters select box to view listings in the show page. now i am not able to access images attached to listings in the category show page. listing.rb attr_accessible :placeholder, :categories_ids has_and_belongs_to_many :categories has_attached_file :placeholder, :styles => { :medium => "300x300>", :thumb => "100x100>" }, :default_url => "/images/:style/missing.png", :url => "/system/:hash.:extension", :hash_secret => "longSecretString" categories controller def index @categories = Category.all end def show @categories = Category.find_by_sql ["select distinct l.* from listings l , categories c, categories_listings cl where c.id = cl.category_id and l.id = cl.listing_id and c.id in (?,?)" , params[:c][:id1] , params[:c][:id2]] end the sql just filters and displays the listings in show page where i can show its attributes, but cant access the placeholder. note the plural @categories in show categories show page <ul> <% @categories.each_with_index do |c, index| %> <% if index == 0 %> <li class="first"><%= c.place %></li> <%= image_tag c.placeholder.url(:thumb) %> <li><%= c.price %></li> <% else %> <li><%= c.place %></li> <li><%= c.price %></li> <%= image_tag c.placeholder.url(:thumb) %> <% end %> <% end %> </ul> Access image from different view in a view with paperclip gem ruby on rails this said to make the object plural and call a loop, wch shall allow to access the image. it does not work in this case. undefined method `placeholder' for #<Category:0x5c78640> but the amazing thing is, placeholder will be displayed as an array of all images for all the listings if used as suggested in that stackoverflow, wch is, obviously, not the way i prefer. where's the issue? what am i missing?

    Read the article

  • Qt Serial Port Errors - Data not getting read

    - by user2970546
    I'm trying to read a serial port with the Qt SerialPort library. I can read the data using HyperTerminal. In Qt I used the following code to try and do the same thing. Qt says the the port has been opened correctly, but for some reason, the bytesAvailable from the serial port is always 0. serial.setPortName("COM20"); if (serial.open(QIODevice::ReadOnly)) qDebug() << "Opened port " << endl; else qDebug() << "Unable to open port" << endl; serial.setDataBits(QSerialPort::Data8); serial.setParity(QSerialPort::EvenParity); serial.setBaudRate(QSerialPort::Baud115200); qDebug() << "Is open?? " << serial.isOpen(); // Wait unit serial port data is ready while (!serial.bytesAvailable()) { //qDebug() << serial.bytesAvailable()<<endl; continue; } QByteArray data = serial.read(100); qDebug() << "This is the data -" << data << endl; serial.close(); In comparison, MATLAB code with the same structure as the above code, successfully manages to read the serial port data %Serial Port Grapher - Shurjo Banerjee s = serial('COM20'); s.BaudRate = 460800; s.Parity = 'even'; try input('Ready to begin?'); catch end fopen(s); fh = figure(); hold on; t = 1; while (s.BytesAvailable <= 0) continue end a = fread(s, 1) old_t = 1; old_a = a; while true if (s.BytesAvailable > 0) a = fread(s, 1) figure(fh) t = t + 1; plot([old_t t], [old_a a]); old_t = t; old_a = a; end end fclose(s);

    Read the article

  • Can continuations be used as a replacement for recursion?

    - by Sam
    The following function generates a 'stack level too deep (SystemStackError)' for n = 5,000 def factorial(n) n == 0 ? 1 : factorial(n -1) * n end Is there a way to avoid this error using continuations/callcc? Note: I know this can be implemented without recursion. e.g. def factorial2(n) (1..n).inject(1) {|result, n| result * n } end

    Read the article

  • What is the fastest cyclic synchronization in Java (ExecutorService vs. CyclicBarrier vs. X)?

    - by Alex Dunlop
    Which Java synchronization construct is likely to provide the best performance for a concurrent, iterative processing scenario with a fixed number of threads like the one outlined below? After experimenting on my own for a while (using ExecutorService and CyclicBarrier) and being somewhat surprised by the results, I would be grateful for some expert advice and maybe some new ideas. Existing questions here do not seem to focus primarily on performance, hence this new one. Thanks in advance! The core of the app is a simple iterative data processing algorithm, parallelized to the spread the computational load across 8 cores on a Mac Pro, running OS X 10.6 and Java 1.6.0_07. The data to be processed is split into 8 blocks and each block is fed to a Runnable to be executed by one of a fixed number of threads. Parallelizing the algorithm was fairly straightforward, and it functionally works as desired, but its performance is not yet what I think it could be. The app seems to spend a lot of time in system calls synchronizing, so after some profiling I wonder whether I selected the most appropriate synchronization mechanism(s). A key requirement of the algorithm is that it needs to proceed in stages, so the threads need to sync up at the end of each stage. The main thread prepares the work (very low overhead), passes it to the threads, lets them work on it, then proceeds when all threads are done, rearranges the work (again very low overhead) and repeats the cycle. The machine is dedicated to this task, Garbage Collection is minimized by using per-thread pools of pre-allocated items, and the number of threads can be fixed (no incoming requests or the like, just one thread per CPU core). V1 - ExecutorService My first implementation used an ExecutorService with 8 worker threads. The program creates 8 tasks holding the work and then lets them work on it, roughly like this: // create one thread per CPU executorService = Executors.newFixedThreadPool( 8 ); ... // now process data in cycles while( ...) { // package data into 8 work items ... // create one Callable task per work item ... // submit the Callables to the worker threads executorService.invokeAll( taskList ); } This works well functionally (it does what it should), and for very large work items indeed all 8 CPUs become highly loaded, as much as the processing algorithm would be expected to allow (some work items will finish faster than others, then idle). However, as the work items become smaller (and this is not really under the program's control), the user CPU load shrinks dramatically: blocksize | system | user | cycles/sec 256k 1.8% 85% 1.30 64k 2.5% 77% 5.6 16k 4% 64% 22.5 4096 8% 56% 86 1024 13% 38% 227 256 17% 19% 420 64 19% 17% 948 16 19% 13% 1626 Legend: - block size = size of the work item (= computational steps) - system = system load, as shown in OS X Activity Monitor (red bar) - user = user load, as shown in OS X Activity Monitor (green bar) - cycles/sec = iterations through the main while loop, more is better The primary area of concern here is the high percentage of time spent in the system, which appears to be driven by thread synchronization calls. As expected, for smaller work items, ExecutorService.invokeAll() will require relatively more effort to sync up the threads versus the amount of work being performed in each thread. But since ExecutorService is more generic than it would need to be for this use case (it can queue tasks for threads if there are more tasks than cores), I though maybe there would be a leaner synchronization construct. V2 - CyclicBarrier The next implementation used a CyclicBarrier to sync up the threads before receiving work and after completing it, roughly as follows: main() { // create the barrier barrier = new CyclicBarrier( 8 + 1 ); // create Runable for thread, tell it about the barrier Runnable task = new WorkerThreadRunnable( barrier ); // start the threads for( int i = 0; i < 8; i++ ) { // create one thread per core new Thread( task ).start(); } while( ... ) { // tell threads about the work ... // N threads + this will call await(), then system proceeds barrier.await(); // ... now worker threads work on the work... // wait for worker threads to finish barrier.await(); } } class WorkerThreadRunnable implements Runnable { CyclicBarrier barrier; WorkerThreadRunnable( CyclicBarrier barrier ) { this.barrier = barrier; } public void run() { while( true ) { // wait for work barrier.await(); // do the work ... // wait for everyone else to finish barrier.await(); } } } Again, this works well functionally (it does what it should), and for very large work items indeed all 8 CPUs become highly loaded, as before. However, as the work items become smaller, the load still shrinks dramatically: blocksize | system | user | cycles/sec 256k 1.9% 85% 1.30 64k 2.7% 78% 6.1 16k 5.5% 52% 25 4096 9% 29% 64 1024 11% 15% 117 256 12% 8% 169 64 12% 6.5% 285 16 12% 6% 377 For large work items, synchronization is negligible and the performance is identical to V1. But unexpectedly, the results of the (highly specialized) CyclicBarrier seem MUCH WORSE than those for the (generic) ExecutorService: throughput (cycles/sec) is only about 1/4th of V1. A preliminary conclusion would be that even though this seems to be the advertised ideal use case for CyclicBarrier, it performs much worse than the generic ExecutorService. V3 - Wait/Notify + CyclicBarrier It seemed worth a try to replace the first cyclic barrier await() with a simple wait/notify mechanism: main() { // create the barrier // create Runable for thread, tell it about the barrier // start the threads while( ... ) { // tell threads about the work // for each: workerThreadRunnable.setWorkItem( ... ); // ... now worker threads work on the work... // wait for worker threads to finish barrier.await(); } } class WorkerThreadRunnable implements Runnable { CyclicBarrier barrier; @NotNull volatile private Callable<Integer> workItem; WorkerThreadRunnable( CyclicBarrier barrier ) { this.barrier = barrier; this.workItem = NO_WORK; } final protected void setWorkItem( @NotNull final Callable<Integer> callable ) { synchronized( this ) { workItem = callable; notify(); } } public void run() { while( true ) { // wait for work while( true ) { synchronized( this ) { if( workItem != NO_WORK ) break; try { wait(); } catch( InterruptedException e ) { e.printStackTrace(); } } } // do the work ... // wait for everyone else to finish barrier.await(); } } } Again, this works well functionally (it does what it should). blocksize | system | user | cycles/sec 256k 1.9% 85% 1.30 64k 2.4% 80% 6.3 16k 4.6% 60% 30.1 4096 8.6% 41% 98.5 1024 12% 23% 202 256 14% 11.6% 299 64 14% 10.0% 518 16 14.8% 8.7% 679 The throughput for small work items is still much worse than that of the ExecutorService, but about 2x that of the CyclicBarrier. Eliminating one CyclicBarrier eliminates half of the gap. V4 - Busy wait instead of wait/notify Since this app is the primary one running on the system and the cores idle anyway if they're not busy with a work item, why not try a busy wait for work items in each thread, even if that spins the CPU needlessly. The worker thread code changes as follows: class WorkerThreadRunnable implements Runnable { // as before final protected void setWorkItem( @NotNull final Callable<Integer> callable ) { workItem = callable; } public void run() { while( true ) { // busy-wait for work while( true ) { if( workItem != NO_WORK ) break; } // do the work ... // wait for everyone else to finish barrier.await(); } } } Also works well functionally (it does what it should). blocksize | system | user | cycles/sec 256k 1.9% 85% 1.30 64k 2.2% 81% 6.3 16k 4.2% 62% 33 4096 7.5% 40% 107 1024 10.4% 23% 210 256 12.0% 12.0% 310 64 11.9% 10.2% 550 16 12.2% 8.6% 741 For small work items, this increases throughput by a further 10% over the CyclicBarrier + wait/notify variant, which is not insignificant. But it is still much lower-throughput than V1 with the ExecutorService. V5 - ? So what is the best synchronization mechanism for such a (presumably not uncommon) problem? I am weary of writing my own sync mechanism to completely replace ExecutorService (assuming that it is too generic and there has to be something that can still be taken out to make it more efficient). It is not my area of expertise and I'm concerned that I'd spend a lot of time debugging it (since I'm not even sure my wait/notify and busy wait variants are correct) for uncertain gain. Any advice would be greatly appreciated.

    Read the article

  • stored procedure in MYsql access in PHP

    - by xcodemaddy
    Hi.. I am creating stored procedure ,here code : CREATE PROCEDURE `dbnm`.`getlogin` ( IN uid INT, IN upass VARCHAR(45) ) BEGIN if exists(select uphno,pass from user_master where uphno=uid and pass=upass)then ***true else ***false end if; END $$ DELIMITER ; i want return value(**true or **false) in stored procedure from PHP by calling sp PHP code: $res = $mysqli->query('call getlogin("1","rashmi")'); how to acesss boolean value in PHP from sp? Thanks

    Read the article

  • Binding the textDidChange event on a NSTextField to a MacRuby delegate

    - by kolrie
    I have a NSTextField within a Window and I created a very simple MacRuby delegate: class ServerInputDelegate attr_accessor :parent def textDidChange(notification) NSLog notification.inspect parent.filter end end And I have tried setting the control's delegate: I have tried setting the Window and every other object I could think of to this delegate. I have also tried setting it to other delegates (application for instance) and events like applicationDidFinishLaunching are being properly triggered. Is there any trick I am missing in order for this event to be triggered every time the contents of this NSTextField changes?

    Read the article

  • How can join two django querysets in one?

    - by diegueus9
    I need order a Queryset by date in desc order, but i need put in the end the objects at the end, I do this: qs1 = Model.objects.exclude(date=None).order_by('-date') qs2 = Model.objects.filter(date=None).order_by('-date') and my list is: l = list(qs1)+list(qs2) There is a more efficiently way for this?

    Read the article

  • Authlogic openid: getting undefined method openid_identifier? error in functional test

    - by usr
    I use Authlogic with the Authlogic-openid addon (I gem installed ruby- openid and script/plugin install git://github.com/rails/open_id_authentication.git) and get two errors. First when running functional test, I get an undefined method openid_identifier? message on a line in my new.html.erb file when running the UsersControllerTest. The line is: <% if @user.openid_identifier? %> When running script/console I can access this method without any problem. Second when testing the openid functionality and registering a new user to my application using openid and using my blogspot account for that I get the following in my log file: Generated checkid_setup request to http://www.blogger.com/openid-server.g with assocication ... Redirected to http://www.blogger.com/openid-server.g?openid.assoc_handle=... NoMethodError (You have a nil object when you didn't expect it! The error occurred while evaluating nil.call): app/controllers/users_controller.rb:44:in `create' /usr/lib/ruby/1.8/webrick/httpserver.rb:104:in `service' /usr/lib/ruby/1.8/webrick/httpserver.rb:65:in `run' /usr/lib/ruby/1.8/webrick/server.rb:173:in `start_thread' /usr/lib/ruby/1.8/webrick/server.rb:162:in `start' /usr/lib/ruby/1.8/webrick/server.rb:162:in `start_thread' /usr/lib/ruby/1.8/webrick/server.rb:95:in `start' /usr/lib/ruby/1.8/webrick/server.rb:92:in `each' /usr/lib/ruby/1.8/webrick/server.rb:92:in `start' /usr/lib/ruby/1.8/webrick/server.rb:23:in `start' /usr/lib/ruby/1.8/webrick/server.rb:82:in `start' The code in the users_controller is straight forward: def create respond_to do |format| @user.save do |result| if result flash[:notice] = t('Thanks for signing up!') format.html { redirect_to :action => 'index' } format.xml { render :xml => @user, :status => :created, :location => @user } else format.html { render :action => "new" } format.xml { render :xml => @user.errors, :status => :unprocessable_entity } end end end end The line giving the error being @user.save do |result|... I feel I'm missing something pretty basic but I have been staring at this for too long because I can't find what it is. I checked with the code on Railscasts episodes 160 and 170 and the bones GitHub project but found nothing. Thanks for your help, usr

    Read the article

  • Extra arguments for Factory Girl

    - by J. Pablo Fernández
    I need to pass extra arguments to factory girl to be used in a callback. Something like this (but more complex really): Factory.define :blog do |blog| blog.name "Blah" blog.after_create do |blog| blog.posts += sample_posts blog.save! end end and then create it with something like this: Factory.create(:blog, :sample_posts => [post1, post2]) Any ideas how to do it?

    Read the article

  • TabBarController rotation problem with popViewControllerAnimated and selectedIndex

    - by rjobidon
    Hi! This is a very important auto rotate issue and easy to reproduce. My application has a UITabBarController. Each tab is a UINavigationController. Auto rotation is handled with normal calls to shouldAutorotateToInterfaceOrientation and didRotateFromInterfaceOrientation. The interface rotates normally until I call UIViewController.popViewControllerAnimated and change UITabBarController.selectedIndex. Steps to reproduce: Create a demo Tab Bar Application. Add the following code to the App Delegate .h file: #import <UIKit/UIKit.h> @interface TestRotation2AppDelegate : NSObject { UIWindow *window; UITabBarController *tabBarController; } @property (nonatomic, retain) IBOutlet UIWindow *window; @property (nonatomic, retain) IBOutlet UITabBarController *tabBarController; (void)doAction; @end // Redefine the interface to cach rotation messages @interface UITabBarController (TestRotation1AppDelegate) @end Add the following code to the App Delegate .m file: #import "TestRotation2AppDelegate.h" @implementation TestRotation2AppDelegate @synthesize window; @synthesize tabBarController; - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { [window addSubview:tabBarController.view]; [window makeKeyAndVisible]; return YES; } - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { return YES; } - (void)dealloc { [tabBarController release]; [window release]; [super dealloc]; } @end @implementation UITabBarController (TestRotation1AppDelegate) - (void)viewDidLoad { [super viewDidLoad]; // Add a third tab and push a view UIViewController *view1 = [[UIViewController alloc] init]; view1.title = @"Third"; UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:view1]; NSMutableArray *array = [[NSMutableArray alloc] init]; [array addObjectsFromArray:self.viewControllers]; [array addObject:nav]; self.viewControllers = array; // Push view2 inside the third tab UIViewController *view2 = [[UIViewController alloc] init]; [nav pushViewController:view2 animated:YES]; // Create a button to pop view2 UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect]; button.frame = CGRectMake(50, 50, 220, 38); [button setTitle:@"Pop this view" forState:UIControlStateNormal]; [button addTarget:self action:@selector(doAction) forControlEvents:UIControlEventTouchUpInside]; [view2.view addSubview:button]; } - (void) doAction { // ROTATION PROBLEM BEGINS HERE // Remove one line of code and the problem doesn't occur. [self.selectedViewController popViewControllerAnimated:YES]; self.selectedIndex = 0; } - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { return YES; } @end The interface auto rotates normally until you tap the button on tab #3. Your help will be geatly appreciated!

    Read the article

  • JSON Post To Rails From Android

    - by Stealthnh
    I'm currently working on an android app that interfaces with a Ruby on Rails app through XML and JSON. I can currently pull all my posts from my website through XML but I can't seem to post via JSON. My app currently builds a JSON object from a form that looks a little something like this: { "post": { "other_param": "1", "post_content": "Blah blah blah" } } On my server I believe the Create method in my Posts Controller is set up correctly: def create @post = current_user.posts.build(params[:post]) respond_to do |format| if @post.save format.html { redirect_to @post, notice: 'Post was successfully created.' } format.json { render json: @post, status: :created, location: @post } format.xml { render xml: @post, status: :created, location: @post } else format.html { render action: "new" } format.json { render json: @post.errors, status: :unprocessable_entity } format.xml { render xml: @post.errors, status: :unprocessable_entity } end end end And in my android app I have a method that takes that JSON Object I posted earlier as a parameter along with the username and password for being authenticated (Authentication is working I've tested it, and yes Simple HTTP authentication is probably not the best choice but its a quick and dirty fix) and it then sends the JSON Object through HTTP POST to the rails server. This is that method: public static void sendPost(JSONObject post, String email, String password) { DefaultHttpClient client = new DefaultHttpClient(); client.getCredentialsProvider().setCredentials(new AuthScope(null,-1), new UsernamePasswordCredentials(email,password)); HttpPost httpPost = new HttpPost("http://mysite.com/posts"); JSONObject holder = new JSONObject(); try { holder.put("post", post); StringEntity se = new StringEntity(holder.toString()); Log.d("SendPostHTTP", holder.toString()); httpPost.setEntity(se); httpPost.setHeader("Content-Type","application/json"); } catch (UnsupportedEncodingException e) { Log.e("Error",""+e); e.printStackTrace(); } catch (JSONException js) { js.printStackTrace(); } HttpResponse response = null; try { response = client.execute(httpPost); } catch (ClientProtocolException e) { e.printStackTrace(); Log.e("ClientProtocol",""+e); } catch (IOException e) { e.printStackTrace(); Log.e("IO",""+e); } HttpEntity entity = response.getEntity(); if (entity != null) { try { entity.consumeContent(); } catch (IOException e) { Log.e("IO E",""+e); e.printStackTrace(); } } } Currently when I call this method and pass it the correct JSON Object it doesn't do anything and I have no clue why or how to figure out what is going wrong. Is my JSON still formatted wrong, does there really need to be that holder around the other data? Or do I need to use something other than HTTP POST? Or is this just something on the Rails end? A route or controller that isn't right? I'd be really grateful if someone could point me in the right direction, because I don't know where to go from here.

    Read the article

  • Memcached and Rails Fragment Caching Issue

    - by Michael Waxman
    When I have 2 views that fragment cache the same query BUT display them differently, there is only one fragment and they both display it the same way. Is there any way around this? For example... #views/posts/list - cache(@posts) do - for p in @posts = p.title #views/posts/list_with_images - cache(@posts) do - for p in @posts = p.title = p.content = image_tag(p.image_url) #controllers/posts_controller def list ... @posts = Post.all end def list_with_images ... @posts = Post.all end

    Read the article

  • Matching sentences with regex in Java

    - by Gary
    Hi, I'm using the Scanner class in java to go through a a text file and extract each sentence. I'm using the setDelimiter method on my Scanner to the regex: Pattern.compile("[\\w]*[\\.|?|!][\\s]") This currently seems to work, but it leaves the whitespace at the end of the sentence. Is there an easy way to match the whitespace at the end but not include it in the result? I realize this is probably an easy question but I've never used regex before so go easy :)

    Read the article

< Previous Page | 276 277 278 279 280 281 282 283 284 285 286 287  | Next Page >