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• New to J2EE; architecture suggestions for a service/daemon?

  - by Kate

  I am brand new to the J2EE world. As an exercise to try and familiarize myself with J2EE, I'm trying to create a tiered web-app, but I'm getting a little stuck on what the best way is to spin up a service in the background that does work. Paramters of the service: It must open and hold a socket connection and receive information from the connected server. There is a 1-to-1 correlation between a user and a new socket connection. So the idea is the user presses a button on the web-page, and somewhere on the server a socket connection is opened. For the remainder of the users session (or until the user presses some sort of disconnect button) the socket remains open and pushes received information to some sort of centralized store that servlets can query and return to the user via AJAX. Is there a J2EE type way to handle this situation? Naturally what I would think to do is to just write a Java application that listens on a port that the servlets can connect to and spawns new threads that open these sockets, but that seems very ad-hoc to me. (PS: I am also new to Stack Overflow, so forgive me if it takes me some time to figure the site out!)

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• Question about permute-by-sorting

  - by davit-datuashvili

  In the book "Introduction to Algorithms", second edition, there is the following problem: Suppose we have some array: int a[] = {1,2,3,4} and some random priorities array: P = {36,3,97,19} and the goal is to permute the array a randomly using this priorities array. This is the pseudo code: PERMUTE-BY-SORTING (A) 1 n ? length[A] 2 for i ? 1 to n 3 do P[i] = RANDOM (1, n 3) 4 sort A, using P as sort keys 5 return A The result should be the permuted array: B={2, 4, 1, 3}; I have written this code: import java.util.*; public class Permute { public static void main (String[] args) { Random r = new Random(); int a[] = new int[] {1,2,3,4}; int n = a.length; int b[] = new int[a.length]; int p[] = new int[a.length]; for (int i=0; i<p.length; i++) { p[i] = r.nextInt(n*n*n) + 1; } // for (int i=0;i<p.length;i++){ // System.out.println(p[i]); //} } } How do I continue?

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• How to select a single object using Linq in vb.net

  - by Hucker

  I have done a lot of searching to what appears to be a simple LINQ problem but I can't figure out how to do grab an object out of a collection that has a specified minimum (or max value) without resorting to a sort like this: > dim customers= GetCustomers() > > dim youngest = (From c in customers > Order By c.age Ascending).ToList.First This (untested code) structure works fine with the exception that the entire customer array must be sorted and placed into a list for the only purpose of extracting the first value. That can't be the best way to get the minimum! Note that I want the whole c record in this case, not the minumum age of a customer that can be done like this (a typical example): > dim customers= GetCustomers() > > dim youngest = (From c in customers > Select c.age).Min Or even > dim customers= GetCustomers() > > dim youngest = (From c in customers > Select c).Min(Function(x) x.age) I can't for the life of me figure out how to get the whole object (or even the index) without resorting to the sort...

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• What is the n in O(n) when comparing sorting algorithms?

  - by Mumfi

  The question is rather simple, but I just can't find a good enough answer. I've taken a look at the most upvoted question regarding the Big-Oh notation, namely this: Plain English explanation of Big O It says there that: For example, sorting algorithms are typically compared based on comparison operations (comparing two nodes to determine their relative ordering). Now let's consider the simple bubble sort algorithm: for (int i = arr.length - 1; i > 0 ; i--) { for (int j = 0; j<i; j++) { if (arr[j] > arr[j+1]) { switchPlaces(...) } } } I know that worst case is O(n^2) and best case is O(n), but what is n exactly? If we attempt to sort an already sorted algorithm (best case), we would end up doing nothing, so why is it still O(n)? We are looping through 2 for-loops still, so if anything it should be O(n^2). n can't be the number of comparison operations, because we still compare all the elements, right? This confuses me, and I appreciate if someone could help me.

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• How costly performance-wise are these actions in iPhone objective-C?

  - by Alex Gosselin

  This is really a few questions in one, I'm wondering what the performance cost is for these things, as I haven't really been following a best practice of any sort for these. The answers may also be useful to other readers, if somebody knows these. (1) If I need the core data managed object context, is it bad to use #import "myAppDelegate.h" //farther down in the code: NSManagedObjectContext *context = [(myAppDelegate.h*)[[UIApplication sharedApplication] delegate] managedObjectContext]; as opposed to leaving the warning you get if you don't cast the delegate? (2) What is the cheapest way to hard-code a string? I have been using return @"myString"; on occasion in some functions where I need to pass it to a variety of places, is it better to do it this way: static NSString *str = @"myString"; return str; (3) How costly is it to subclass an object i wrote vs. making a new one, in general? (4) When I am using core data and navigating through a hierarchy of some sort, is it necessary to turn things back into faults somehow after I read some info from them? or is this done automatically? Thanks for any help.

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• Do running times match with O(nlogn)?

  - by user472221

  Hi I have written a class(greedy strategy) that at first i used sort method which has O(nlogn) Collections.sort(array, new SortingObjectsWithProbabilityField()); and then i used the insert method of binary search tree which takes O(h) and h here is the tree height. for different n ,the running time will be : n,running time 17,515428 33,783340 65,540572 129,1285080 257,2052216 513,4299709 which I think is not correct because for increasing n , the running time should almost increase. This method will take the running time: Exponent = -1; for(int n = 2;n<1000;n+=Math.pow(2,exponent){ for (int j = 1; j <= 3; j++) { Random rand = new Random(); for (int i = 0; i < n; i++) { Element e = new Element(rand.nextInt(100) + 1, rand.nextInt(100) + 1, 0); for (int k = 0; k < i; k++) { if (e.getDigit() == randList.get(k).getDigit()) { e.setDigit(e.getDigit() + 1); } } randList.add(e); } double sum = 0.0; for (int i = 0; i < randList.size(); i++) { sum += randList.get(i).getProbability(); } for (Element i : randList) { i.setProbability(i.getProbability() / sum); } //Get time. long t2 = System.nanoTime(); GreedyVersion greedy = new GreedyVersion((ArrayList<Element>) randList); long t3 = System.nanoTime(); timeForGreedy = timeForGreedy + t3 - t2; } System.out.println(n + "," + "," + timeForGreedy/3 ); exponent++; } thanks

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• How to synchronize access to many objects

  - by vividos

  I have a thread pool with some threads (e.g. as many as number of cores) that work on many objects, say thousands of objects. Normally I would give each object a mutex to protect access to its internals, lock it when I'm doing work, then release it. When two threads would try to access the same object, one of the threads has to wait. Now I want to save some resources and be scalable, as there may be thousands of objects, and still only a hand full of threads. I'm thinking about a class design where the thread has some sort of mutex or lock object, and assigns the lock to the object when the object should be accessed. This would save resources, as I only have as much lock objects as I have threads. Now comes the programming part, where I want to transfer this design into code, but don't know quite where to start. I'm programming in C++ and want to use Boost classes where possible, but self written classes that handle these special requirements are ok. How would I implement this? My first idea was to have a boost::mutex object per thread, and each object has a boost::shared_ptr that initially is unset (or NULL). Now when I want to access the object, I lock it by creating a scoped_lock object and assign it to the shared_ptr. When the shared_ptr is already set, I wait on the present lock. This idea sounds like a heap full of race conditions, so I sort of abandoned it. Is there another way to accomplish this design? A completely different way?

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• Java order jlist by status

  - by Takami

  i have a small problem, i don't know how to sort my jlist by status which is retrieved from database. i want sort by "online" and "offline", i mean online computers go first and then offline computers, i have this code now, it just makes the icon+text for the jlist Can you tell me how can i filter/sortby status? public void acx_pc(String query) { try { Statement st = con.createStatement(); ResultSet rs = st.executeQuery(query); String comb; Map<Object, Icon> icons = new HashMap<>(); ArrayList<String> pc_list = new ArrayList<>(); int i = 0; while (rs.next()) { //Getting info from DB String pc_name = rs.getString("nombre_pc"); String pc_ip = rs.getString("IP"); String status = rs.getString("estado"); //Setting text for the jList comb = pc_name + " - " + pc_ip; //Comparing Status switch (status) { case "online": //This is just for rendering an image+text to Jlist icons.put(comb, new ImageIcon(getClass().getResource("/Imagenes/com_on_30x30.png"))); break; case "offline": //This is just for rendering an image to Jlist icons.put(comb, new ImageIcon(getClass().getResource("/Imagenes/com_off_30x30.png"))); break; } //Adding info to ArrayList pc_list.add(i, comb); i++; } con.close(); // Setting the list/text on Jlist Home.computer_jlist.setListData(pc_list.toArray()); // create a cell renderer to add the appropriate icon Home.computer_jlist.setCellRenderer(new pc_cell_render(icons)); } catch (Exception e) { System.out.println("Error aqui: " + e); } } I want to do something like (should automatically order) http://imageshack.us/a/img27/9018/2mx1.png and not: http://imageshack.us/a/img407/346/e9r.png

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• Some ASP.NET and Access

  - by Fazleh

  Good Day all, I have a big problem but i think its minor for you guys in Stackoverflow. I am creating a web application that has two main parts. The Payment part and Requisition part. It backbone is using access and the script is in ASP.NET. I managed to sort out most of the application. But I have been having a few problems. I have pasted the link to the project in http://www.mediafire.com/download/p09fefreifidud3/Inyatsi.rar so it will be easy for someone to see what I am blabbing about. Now for my problems: The AddRequisition.aspx/AddPayment.aspx: both have a reference number. I wanted it to be unique number(but not a primary key). I wanted it to be in the following format: DDMMYY(TransactionNo)(UserID) eg: 24061101PK. I have tried and tried but have not been able to sort it out. The AmountINWords gets the value from Amount. It converts the Amount into words. Thats not all. It picks what currncy was picked in the CurrencyPaidIn and pust the respective currency inside. eg. 123.45 USD becomes One Hundred and twenty three dollars and forty five cents. I tried using queries but as you will see that went all wrong. Those are the only two things that I cant seem to get my head around. I do know that there are some things that are not conventional ASP.NET and some text boxes are not the right size. I was thinking of sorting out those after I get those two fixed because they are simple to do. I really need some help with this application please. If someone can just have a look at the code and add a few things here and there. Thanks in advance. Faz

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• Python: Sorting array with custom pattern

  - by Binka

  In my little project here I have sorted a list in decending order, however, my goal is to sort it in this custom pattern. (largest - smallest - next largest - next smallest -)etc. In java I was able to do this like this... My goal is to do the same thing but in python, except backwards. Any ideas on how to convert that last for loop that does the wackysort into python and make it go backwards? public static void wackySort(int[] nums){ //first, this simply sorts the array by ascending order. int sign = 0; int temp = 0; int temp2 = 0; for (int i = 0; i < nums.length; i++){ for (int j = 0; j < nums.length -1; j++){ if (nums[j] > nums[j+1]){ temp = nums[j]; nums[j] = nums[j+1]; nums[j+1] = temp; } } } //prepare for new array to actually do the wacky sort. System.out.println(); int firstPointer = 0; int secondPointer = nums.length -1; int[] newarray = new int[nums.length]; int size = nums.length; //for loop that increments by two taking second slot replacing the last (n-1) term for (int i = 0; i < nums.length -1; i+=2){ newarray[i] = nums[firstPointer++]; newarray[i+1] = nums[secondPointer--]; } //storing those values back in the nums array for (int i = 0; i < nums.length; i++){ nums[i] = newarray[i]; } }

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• Detect if Download is Complete

  - by user604138

  I have a very simple and standard PHP force download script. How do I check if/when the download has completed in order to notify the user on the clientside? I don't even need to show the progress in real time, I am only interested in the very specific event: "when the download completes". Based on my research, it seems like it would have to be determined from the serverside as there is noondownloadready event and I don't think it is possible to intercept browser events. So it seems that my best bet would be to compare bytes sent to total bytes with some sort of clientside/severside interaction. How would I go about checking the bytes sent from the server for a PHP forced download? is there some sort of global PHP variable that store these data that I can ping with AJAX? <?php header("Content-Type: video/x-msvideo"); header("Content-Disposition: attachment; filename=\"".basename($realpath)."\";"); ... $chunksize = 1 * (1024 * 1024); // how many bytes per chunk if ($size > $chunksize) { $handle = fopen($realpath, 'rb'); $buffer = ''; while (!feof($handle)) { $buffer = fread($handle, $chunksize); echo $buffer; ob_flush(); flush(); } fclose($handle); } else { readfile($realpath); } exit(); ?> The reason I need this: For the project I am working on, it is required that after the download starts, the page redirects to (or displays) a "please wait while the download completes" page. Then, once it is complete, it should redirect to (or display) a "Your download is complete, thank you" page. I am open to other ideas that would achieve the same result.

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• PDF reviewer in C# (ASP.NET/Silverlight?)

  - by Anders Holmström

  Hi. I'm essentially planning to mimic the comment functions on PDF files, but online. That is; a user should be able to log in and upload a PDF file, and then numerous different users should be able to add comments etc to this same file (and view the file, with comments, online). External libraries are ok. Free obviously preferred, but commercial ones are fine if they provide a lot of the needed functionality. Note that this is meant to be used in a commercial environment. Comments don't necessarily need to be able to be exported from the site. I.e. if the comments are just put as a layer on top of a PDF file (and not in the actual file) that's ok. But obviously the more export functionality the better. I have looked at a few libraries (using the related questions and google) and while I find some that seem to do sort of what I want I'm not sure they are the bee's knees plus I would like to do as much myself as possible. The three basic approaches I've thought of is: Use some sort of native PDF viewing and then just smack down a layer on top of it where you can move around comments etc. Convert PDFs to HTML and work from there. Problem here it would either require proper PDFs (e.g. non-scanned) or really good OCR which seems a bit tedious. Convert PDFs to images and work from there. I'm afraid this will create massive images however. We're talking PDFs that can be hundreds of pages. One option would of course to just display one PDF page (image) at a time. And last - should I look at Silverlight for this or go with ASP.NET? Ideas and input concerning this project are much appreciated.

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• How do I add events to nested server controls? (ASP.Net)

  - by bert

  I am building a custom master page type control i.e. sort of like a datagrid but should be easier to add custom functionality into it. It's going great but part of the desired functionality is to have a paging control that switches on and off and part of that control would be a textbox that displays the current page number and on TextChanged redirects to the new page of the dataset. The problem I'm having is that technically the textbox which has its event fired is embedded in a control that is embedded in the control you actually put on the page sort of like Page  | Display Control  | Paging Control  | Textbox Buried all the way down there the event is not firing. Worse the postback javascript isn't even being written onto the page (Nothing on the page posts back so far this is the only bit that really needs to). I've been trawling around Google for quite a while now and picked up that I need to implement INamingContainer (done) and I need to add the control into the page's control tree (is Pre_Init too late for that? When's a good time to Add the Control to the page?) then the event should fire, apparently. But I've been unable to find an example of best practice on this there are quite a few near misses where people are having button angst but this isn't a button. So can anyone point me in the direction of getting a control embedded in a control embedded in a control added to a page to behave properly?

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• Improved technique to store a filename in a variable?

  - by SDGuero

  Greetings, I need to store the filename of a log into a variable so my script can perform some checks on the daily log files. These logs always have a different name because they have a timestamp in the name. Currently I'm using a hodge podged method that pipes an ls command to sed, sort, cut, and tail in order to get the name out. CRON_LOG=$(ls -1 $LOGS_DIR/fetch_cron_{true,false}_$CRON_DATE*.log 2> /dev/null | sed 's/^[^0-9][^0-9]*\([0-9][0-9]*\).*/\1 &/' | sort -n | cut -d ' ' -f2- | tail -1 ) UPDATE: $CRON_DATE is supplied as an argument to the script. It is the date (to the day) that the log was created on. Sometimes multiple logs will exist for the same day so I want this to get the most recent one. A typical filename is fetch_cron_false_031810090452.log I'm pretty sure I kluged this together from some stuff I found google a few months ago. it works now but I'm not really happy with the technique. I have some ideas about how to do this better but I have had great success on this site before and thought it might be best to refer to the stackoverflow gods first. All answers are greatly appreciated. Thanks, Ryan

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• Can I use a UINavigationController as the detail view of a UISplitViewController?

  - by B Sweigard

  I'm running into a problem with an iPad app where I would like to have UINavigationControllers in both of the views within a UISplitView. I've looked through other similar questions here, but most link to a tutorial online that doesn't completely solve the problem. Here's a 2-minute walkthrough to re-create the problem I'm having: Create a New Project in XCode, starting from the Split View-based Application template. Add the following NSLog statement as the first line within the DetailViewController's willHideViewController method: NSLog(@"toolbar: %@", toolbar); If you run the application now, the log will show that the DetailViewController's toolbar is alive and well. Now... Open MainWindow.xib and expand the SplitViewController. Drag a Navigation Controller from the library on top of the DetailViewController. Expand the new Navigation Controller and change the class of the UIViewController within to a DetailViewController. Ctrl-drag from the SplitViewController to the DetailViewController and assign it as the delegate. Save MainWindow.xib and run the app again. At this point, the detail view has a navigation bar and an empty toolbar. If you view the logs, you should find that the toolbar is null. Why is this? Am I missing some sort of connection in Interface Builder? Is the navigation bar the problem for some reason? Unlike the tutorial at http://www.cimgf.com/2010/05/24/fixing-the-uisplitviewcontroller-template/, I would like to keep both the navigation bar and the toolbar (preferably with the toolbar at the top when in portrait and not visible when in landscape), so that I still have a functional "Back" button when the iPad is in portrait orientation. Does anyone have any suggestions for fixing this problem? An example project with this sort of set-up would be ideal.

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• How can I create an array of random numbers in C++

  - by Nick

  Instead of The ELEMENTS being 25 is there a way to randomly generate a large array of elements....10000, 100000, or even 1000000 elements and then use my insertion sort algorithms. I am trying to have a large array of elements and use insertion sort to put them in order and then also in reverse order. Next I used clock() in the time.h file to figure out the run time of each algorithm. I am trying to test with a large amount of numbers. #define ELEMENTS 25 void insertion_sort(int x[],int length); void insertion_sort_reverse(int x[],int length); int main() { clock_t tStart = clock(); int B[ELEMENTS]={4,2,5,6,1,3,17,14,67,45,32,66,88, 78,69,92,93,21,25,23,71,61,59,60,30}; int x; cout<<"Not Sorted: "<<endl; for(x=0;x<ELEMENTS;x++) cout<<B[x]<<endl; insertion_sort(B,ELEMENTS); cout <<"Sorted Normal: "<<endl; for(x=0;x<ELEMENTS;x++) cout<< B[x] <<endl; insertion_sort_reverse(B,ELEMENTS); cout <<"Sorted Reverse: "<<endl; for(x=0;x<ELEMENTS;x++) cout<< B[x] <<endl; double seconds = clock() / double(CLK_TCK); cout << "This program has been running for " << seconds << " seconds." << endl; system("pause"); return 0; }

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• question about permut-by-sorting

  - by davit-datuashvili

  hi i have following question from book introduction in algorithms second edition there is such problem suppose we have some array A int a[]={1,2,3,4} and we have some random priorities array P={36,3,97,19} we shoud permut array a randomly using this priorities array here is pseudo code P ERMUTE -B Y-S ORTING ( A) 1 n ? length[A] 2 for i ? 1 to n do P[i] = R ANDOM(1, n 3 ) 3 4 sort A, using P as sort keys 5 return A and result will be permuted array B={2, 4, 1, 3}; please help any ideas i have done this code and need aideas how continue import java.util.*; public class Permut { public static void main(String[]args){ Random r=new Random(); int a[]=new int[]{1,2,3,4}; int n=a.length; int b[]=new int[a.length]; int p[]=new int[a.length]; for (int i=0;i<p.length;i++){ p[i]=r.nextInt(n*n*n)+1; } // for (int i=0;i<p.length;i++){ // System.out.println(p[i]); //} } } please help

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• Ruby on Rails sortable list

  - by mdgrech

  I created a sortable list in my RoR project, unfortunately it's not saving the list position. Upon page refresh the items return to their normal spot. I've pasted the code below or you can git it: git://github.com/mdgrech/23notes-.git app/views/notes/index.html.erb ///////////////////////////////////////////////////////////////////////////////////////////// <div id="newNoteDiv"></div> <ul id="notesList"> <% for note in @notes %> <li id="<%=h note.position %>"> <span class="handle">[drag]</span> <div id="listContent"> <h3><%= link_to note.title, edit_note_path(note) %></h3> <p><%=h note.content %></p> <%= link_to "Destroy", note, :confirm => 'Are you sure?', :method => :delete %> </div> </li> <% end %> </ul> <%= sortable_element("notesList", :url => sort_notes_path, :handle => "handle" ) %> app/controllers/notes_controller.rb ////////////////////////////////////////////////////////////////////////////////////////// def index @notes = Note.all(:order => "position") end def sort params[:notes].each_with_index do |id, index| Note.update_all(['position=?', index+1], ['id=?', id]) end render :nothing => true end config/routes.rb ////////////////////////////////////////////////////////////////////////////////////////// map.resources :notes, :collection => { :sort => :post } map.root :notes app/models/note.rb ////////////////////////////////////////////////////////////////////////////////////////// class Note < ActiveRecord::Base acts_as_list end

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• How to control div on hover:?

  - by AAA

  I found a way to change the background color of a menu option upon hover. However, when you hover an option, it takes up some wide space that moves all the other options to the right, its sort of annoying, i want to maintain a consistent space, so if i hover, only the color should change, not the option moving to the right. Sort of the way facebook has its menu options. Below is the code: <div id="menu"> <a href="/hello" id="option">home</a> <a href="/hello" id="option">profile</a> <a href="/hello" id="option">account</a> <a href="/hello" id="option">settings</a> <a href="/hello" id="option">extra</a> <a href="/hello" id="option">logout</a> </div> CSS: div#menu { margin-left: 630px; margin-top:-20px; } option { margin-left: 20px; } #option:hover{ background: #3F2327; padding: 10px; }

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• Finding k elements of length-n list that sum to less than t in O(nlogk) time

  - by tresbot

  This is from Programming Pearls ed. 2, Column 2, Problem 8: Given a set of n real numbers, a real number t, and an integer k, how quickly can you determine whether there exists a k-element subset of the set that sums to at most t? One easy solution is to sort and sum the first k elements, which is our best hope to find such a sum. However, in the solutions section Bentley alludes to a solution that takes nlog(k) time, though he gives no hints for how to find it. I've been struggling with this; one thought I had was to go through the list and add all the elements less than t/k (in O(n) time); say there are m1 < k such elements, and they sum to s1 < t. Then we are left needing k - m1 elements, so we can scan through the list again in O(n) time looking for all elements less than (t - s1)/(k - m1). Add in again, to get s2 and m2, then again if m2 < k, look for all elements less than (t - s2)/(k - m2). So: def kSubsetSumUnderT(inList, k, t): outList = [] s = 0 m = 0 while len(outList) < k: toJoin = [i for i in inList where i < (t - s)/(k - m)] if len(toJoin): if len(toJoin) >= k - m: toJoin.sort() if(s0 + sum(toJoin[0:(k - m - 1)]) < t: return True return False outList = outList + toJoin s += sum(toJoin) m += len(toJoin) else: return False My intuition is that this might be the O(nlog(k)) algorithm, but I am having a hard time proving it to myself. Thoughts?

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• A Guided Tour of Complexity

  - by JoshReuben

  I just re-read Complexity – A Guided Tour by Melanie Mitchell , protégé of Douglas Hofstadter ( author of “Gödel, Escher, Bach”) http://www.amazon.com/Complexity-Guided-Tour-Melanie-Mitchell/dp/0199798109/ref=sr_1_1?ie=UTF8&qid=1339744329&sr=8-1 here are some notes and links:   Evolved from Cybernetics, General Systems Theory, Synergetics some interesting transdisciplinary fields to investigate: Chaos Theory - http://en.wikipedia.org/wiki/Chaos_theory – small differences in initial conditions (such as those due to rounding errors in numerical computation) yield widely diverging outcomes for chaotic systems, rendering long-term prediction impossible. System Dynamics / Cybernetics - http://en.wikipedia.org/wiki/System_Dynamics – study of how feedback changes system behavior Network Theory - http://en.wikipedia.org/wiki/Network_theory – leverage Graph Theory to analyze symmetric  / asymmetric relations between discrete objects Algebraic Topology - http://en.wikipedia.org/wiki/Algebraic_topology – leverage abstract algebra to analyze topological spaces There are limits to deterministic systems & to computation. Chaos Theory definitely applies to training an ANN (artificial neural network) – different weights will emerge depending upon the random selection of the training set. In recursive Non-Linear systems http://en.wikipedia.org/wiki/Nonlinear_system – output is not directly inferable from input. E.g. a Logistic map: Xt+1 = R Xt(1-Xt) Different types of bifurcations, attractor states and oscillations may occur – e.g. a Lorenz Attractor http://en.wikipedia.org/wiki/Lorenz_system Feigenbaum Constants http://en.wikipedia.org/wiki/Feigenbaum_constants express ratios in a bifurcation diagram for a non-linear map – the convergent limit of R (the rate of period-doubling bifurcations) is 4.6692016 Maxwell’s Demon - http://en.wikipedia.org/wiki/Maxwell%27s_demon - the Second Law of Thermodynamics has only a statistical certainty – the universe (and thus information) tends towards entropy. While any computation can theoretically be done without expending energy, with finite memory, the act of erasing memory is permanent and increases entropy. Life & thought is a counter-example to the universe’s tendency towards entropy. Leo Szilard and later Claude Shannon came up with the Information Theory of Entropy - http://en.wikipedia.org/wiki/Entropy_(information_theory) whereby Shannon entropy quantifies the expected value of a message’s information in bits in order to determine channel capacity and leverage Coding Theory (compression analysis). Ludwig Boltzmann came up with Statistical Mechanics - http://en.wikipedia.org/wiki/Statistical_mechanics – whereby our Newtonian perception of continuous reality is a probabilistic and statistical aggregate of many discrete quantum microstates. This is relevant for Quantum Information Theory http://en.wikipedia.org/wiki/Quantum_information and the Physics of Information - http://en.wikipedia.org/wiki/Physical_information. Hilbert’s Problems http://en.wikipedia.org/wiki/Hilbert's_problems pondered whether mathematics is complete, consistent, and decidable (the Decision Problem – http://en.wikipedia.org/wiki/Entscheidungsproblem – is there always an algorithm that can determine whether a statement is true).  Godel’s Incompleteness Theorems http://en.wikipedia.org/wiki/G%C3%B6del's_incompleteness_theorems  proved that mathematics cannot be both complete and consistent (e.g. “This statement is not provable”). Turing through the use of Turing Machines (http://en.wikipedia.org/wiki/Turing_machine symbol processors that can prove mathematical statements) and Universal Turing Machines (http://en.wikipedia.org/wiki/Universal_Turing_machine Turing Machines that can emulate other any Turing Machine via accepting programs as well as data as input symbols) that computation is limited by demonstrating the Halting Problem http://en.wikipedia.org/wiki/Halting_problem (is is not possible to know when a program will complete – you cannot build an infinite loop detector). You may be used to thinking of 1 / 2 / 3 dimensional systems, but Fractal http://en.wikipedia.org/wiki/Fractal systems are defined by self-similarity & have non-integer Hausdorff Dimensions !!!  http://en.wikipedia.org/wiki/List_of_fractals_by_Hausdorff_dimension – the fractal dimension quantifies the number of copies of a self similar object at each level of detail – eg Koch Snowflake - http://en.wikipedia.org/wiki/Koch_snowflake Definitions of complexity: size, Shannon entropy, Algorithmic Information Content (http://en.wikipedia.org/wiki/Algorithmic_information_theory - size of shortest program that can generate a description of an object) Logical depth (amount of info processed), thermodynamic depth (resources required). Complexity is statistical and fractal. John Von Neumann’s other machine was the Self-Reproducing Automaton http://en.wikipedia.org/wiki/Self-replicating_machine  . Cellular Automata http://en.wikipedia.org/wiki/Cellular_automaton are alternative form of Universal Turing machine to traditional Von Neumann machines where grid cells are locally synchronized with their neighbors according to a rule. Conway’s Game of Life http://en.wikipedia.org/wiki/Conway's_Game_of_Life demonstrates various emergent constructs such as “Glider Guns” and “Spaceships”. Cellular Automatons are not practical because logical ops require a large number of cells – wasteful & inefficient. There are no compilers or general program languages available for Cellular Automatons (as far as I am aware). Random Boolean Networks http://en.wikipedia.org/wiki/Boolean_network are extensions of cellular automata where nodes are connected at random (not to spatial neighbors) and each node has its own rule –> they demonstrate the emergence of complex  & self organized behavior. Stephen Wolfram’s (creator of Mathematica, so give him the benefit of the doubt) New Kind of Science http://en.wikipedia.org/wiki/A_New_Kind_of_Science proposes the universe may be a discrete Finite State Automata http://en.wikipedia.org/wiki/Finite-state_machine whereby reality emerges from simple rules. I am 2/3 through this book. It is feasible that the universe is quantum discrete at the plank scale and that it computes itself – Digital Physics: http://en.wikipedia.org/wiki/Digital_physics – a simulated reality? Anyway, all behavior is supposedly derived from simple algorithmic rules & falls into 4 patterns: uniform , nested / cyclical, random (Rule 30 http://en.wikipedia.org/wiki/Rule_30) & mixed (Rule 110 - http://en.wikipedia.org/wiki/Rule_110 localized structures – it is this that is interesting). interaction between colliding propagating signal inputs is then information processing. Wolfram proposes the Principle of Computational Equivalence - http://mathworld.wolfram.com/PrincipleofComputationalEquivalence.html - all processes that are not obviously simple can be viewed as computations of equivalent sophistication. Meaning in information may emerge from analogy & conceptual slippages – see the CopyCat program: http://cognitrn.psych.indiana.edu/rgoldsto/courses/concepts/copycat.pdf Scale Free Networks http://en.wikipedia.org/wiki/Scale-free_network have a distribution governed by a Power Law (http://en.wikipedia.org/wiki/Power_law - much more common than Normal Distribution). They are characterized by hubs (resilience to random deletion of nodes), heterogeneity of degree values, self similarity, & small world structure. They grow via preferential attachment http://en.wikipedia.org/wiki/Preferential_attachment – tipping points triggered by positive feedback loops. 2 theories of cascading system failures in complex systems are Self-Organized Criticality http://en.wikipedia.org/wiki/Self-organized_criticality and Highly Optimized Tolerance http://en.wikipedia.org/wiki/Highly_optimized_tolerance. Computational Mechanics http://en.wikipedia.org/wiki/Computational_mechanics – use of computational methods to study phenomena governed by the principles of mechanics. This book is a great intuition pump, but does not cover the more mathematical subject of Computational Complexity Theory – http://en.wikipedia.org/wiki/Computational_complexity_theory I am currently reading this book on this subject: http://www.amazon.com/Computational-Complexity-Christos-H-Papadimitriou/dp/0201530821/ref=pd_sim_b_1   stay tuned for that review!

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• Building a jQuery Plug-in to make an HTML Table scrollable

  - by Rick Strahl

  Today I got a call from a customer and we were looking over an older application that uses a lot of tables to display financial and other assorted data. The application is mostly meta-data driven with lots of layout formatting automatically driven through meta data rather than through explicit hand coded HTML layouts. One of the problems in this apps are tables that display a non-fixed amount of data. The users of this app don't want to use paging to see more data, but instead want to display overflow data using a scrollbar. Many of the forms are very densely populated, often with multiple data tables that display a few rows of data in the UI at the most. This sort of layout does not lend itself well to paging, but works much better with scrollable data. Unfortunately scrollable tables are not easily created. HTML Tables are mangy beasts as anybody who's done any sort of Web development knows. Tables are finicky when it comes to styling and layout, and they have many funky quirks, especially when it comes to scrolling both of the table rows themselves or even the child columns. There's no built-in way to make tables scroll and to lock headers while you do, and while you can embed a table (or anything really) into a scrolling div with something like this: <div style="position:relative; overflow: hidden; overflow-y: scroll; height: 200px; width: 400px;"> <table id="table" style="width: 100%" class="blackborder" > <thead> <tr class="gridheader"> <th>Column 1</th> <th>Column 2</th> <th>Column 3</th> <th >Column 4</th> </tr> </thead> <tbody> <tr> <td>Column 1 Content</td> <td>Column 2 Content</td> <td>Column 3 Content</td> <td>Column 4 Content</td> </tr> <tr> <td>Column 1 Content</td> <td>Column 2 Content</td> <td>Column 3 Content</td> <td>Column 4 Content</td> </tr> … </tbody> </table> </div> </div> that won't give a very satisfying visual experience: Both the header and body scroll which looks odd. You lose context as soon as the header scrolls off the top and when you reach the bottom of the list the bottom outline of the table shows which also looks off. The the side bar shows all the way down the length of the table yet another visual miscue. In a pinch this will work, but it's ugly. What's out there? Before we go further here you should know that there are a few capable grid plug-ins out there already. Among them: Flexigrid (can work of any table as well as with AJAX data) jQuery Scrollable Table Plug-in (feature similar to what I need but not quite) jqGrid (mostly an Ajax Grid which is very powerful and works very well) But in the end none of them fit the bill of what I needed in this situation. All of these require custom CSS and some of them are fairly complex to restyle. Others are AJAX only or work better with AJAX loaded data. However, I need to actually try (as much as possible) to maintain the original styling of the tables without requiring extensive re-styling. Building the makeTableScrollable() Plug-in To make a table scrollable requires rearranging the table a bit. In the plug-in I built I create two <div> tags and split the table into two: one for the table header and one for the table body. The bottom <div> tag then contains only the table's row data and can be scrolled while the header stays fixed. Using jQuery the basic idea is pretty simple: You create the divs, copy the original table into the bottom, then clone the table, clear all content append the <thead> section, into new table and then copy that table into the second header <div>. Easy as pie, right? Unfortunately it's a bit more complicated than that as it's tricky to get the width of the table right to account for the scrollbar (by adding a small column) and making sure the borders properly line up for the two tables. A lot of style settings have to be made to ensure the table is a fixed size, to remove and reattach borders, to add extra space to allow for the scrollbar and so forth. The end result of my plug-in is a table with a scrollbar. Using the same table I used earlier the result looks like this: To create it, I use the following jQuery plug-in logic to select my table and run the makeTableScrollable() plug-in against the selector: $("#table").makeTableScrollable( { cssClass:"blackborder"} ); Without much further ado, here's the short code for the plug-in: (function ($) { $.fn.makeTableScrollable = function (options) { return this.each(function () { var $table = $(this); var opt = { // height of the table height: "250px", // right padding added to support the scrollbar rightPadding: "10px", // cssclass used for the wrapper div cssClass: "" } $.extend(opt, options); var $thead = $table.find("thead"); var $ths = $thead.find("th"); var id = $table.attr("id"); var cssClass = $table.attr("class"); if (!id) id = "_table_" + new Date().getMilliseconds().ToString(); $table.width("+=" + opt.rightPadding); $table.css("border-width", 0); // add a column to all rows of the table var first = true; $table.find("tr").each(function () { var row = $(this); if (first) { row.append($("<th>").width(opt.rightPadding)); first = false; } else row.append($("<td>").width(opt.rightPadding)); }); // force full sizing on each of the th elemnts $ths.each(function () { var $th = $(this); $th.css("width", $th.width()); }); // Create the table wrapper div var $tblDiv = $("<div>").css({ position: "relative", overflow: "hidden", overflowY: "scroll" }) .addClass(opt.cssClass); var width = $table.width(); $tblDiv.width(width).height(opt.height) .attr("id", id + "_wrapper") .css("border-top", "none"); // Insert before $tblDiv $tblDiv.insertBefore($table); // then move the table into it $table.appendTo($tblDiv); // Clone the div for header var $hdDiv = $tblDiv.clone(); $hdDiv.empty(); var width = $table.width(); $hdDiv.attr("style", "") .css("border-bottom", "none") .width(width) .attr("id", id + "_wrapper_header"); // create a copy of the table and remove all children var $newTable = $($table).clone(); $newTable.empty() .attr("id", $table.attr("id") + "_header"); $thead.appendTo($newTable); $hdDiv.insertBefore($tblDiv); $newTable.appendTo($hdDiv); $table.css("border-width", 0); }); } })(jQuery); Oh sweet spaghetti code :-) The code starts out by dealing the parameters that can be passed in the options object map: height The height of the full table/structure. The height of the outside wrapper container. Defaults to 200px. rightPadding The padding that is added to the right of the table to account for the scrollbar. Creates a column of this width and injects it into the table. If too small the rightmost column might get truncated. if too large the empty column might show. cssClass The CSS class of the wrapping container that appears to wrap the table. If you want a border around your table this class should probably provide it since the plug-in removes the table border. The rest of the code is obtuse, but pretty straight forward. It starts by creating a new column in the table to accommodate the width of the scrollbar and avoid clipping of text in the rightmost column. The width of the columns is explicitly set in the header elements to force the size of the table to be fixed and to provide the same sizing when the THEAD section is moved to a new copied table later. The table wrapper div is created, formatted and the table is moved into it. The new wrapper div is cloned for the header wrapper and configured. Finally the actual table is cloned and cleared of all elements. The original table's THEAD section is then moved into the new table. At last the new table is added to the header <div>, and the header <div> is inserted before the table wrapper <div>. I'm always amazed how easy jQuery makes it to do this sort of re-arranging, and given of what's happening the amount of code is rather small. Disclaimer: Your mileage may vary A word of warning: I make no guarantees about the code above. It's a first cut and I provided this here mainly to demonstrate the concepts of decomposing and reassembling an HTML layout :-) which jQuery makes so nice and easy. I tested this component against the typical scenarios we plan on using it for which are tables that use a few well known styles (or no styling at all). I suspect if you have complex styling on your <table> tag that things might not go so well. If you plan on using this plug-in you might want to minimize your styling of the table tag and defer any border formatting using the class passed in via the cssClass parameter, which ends up on the two wrapper div's that wrap the header and body rows. There's also no explicit support for footers. I rarely if ever use footers (when not using paging that is), so I didn't feel the need to add footer support. However, if you need that it's not difficult to add - the logic is the same as adding the header. The plug-in relies on a well-formatted table that has THEAD and TBODY sections along with TH tags in the header. Note that ASP.NET WebForm DataGrids and GridViews by default do not generate well-formatted table HTML. You can look at my Adding proper THEAD sections to a GridView post for more info on how to get a GridView to render properly. The plug-in has no dependencies other than jQuery. Even with the limitations in mind I hope this might be useful to some of you. I know I've already identified a number of places in my own existing applications where I will be plugging this in almost immediately. Resources Download Sample and Plug-in code Latest version in the West Wind Web & AJAX Toolkit Repository © Rick Strahl, West Wind Technologies, 2005-2011Posted in jQuery  HTML  ASP.NET  

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• What's up with OCFS2?

  - by wcoekaer

  On Linux there are many filesystem choices and even from Oracle we provide a number of filesystems, all with their own advantages and use cases. Customers often confuse ACFS with OCFS or OCFS2 which then causes assumptions to be made such as one replacing the other etc... I thought it would be good to write up a summary of how OCFS2 got to where it is, what we're up to still, how it is different from other options and how this really is a cool native Linux cluster filesystem that we worked on for many years and is still widely used. Work on a cluster filesystem at Oracle started many years ago, in the early 2000's when the Oracle Database Cluster development team wrote a cluster filesystem for Windows that was primarily focused on providing an alternative to raw disk devices and help customers with the deployment of Oracle Real Application Cluster (RAC). Oracle RAC is a cluster technology that lets us make a cluster of Oracle Database servers look like one big database. The RDBMS runs on many nodes and they all work on the same data. It's a Shared Disk database design. There are many advantages doing this but I will not go into detail as that is not the purpose of my write up. Suffice it to say that Oracle RAC expects all the database data to be visible in a consistent, coherent way, across all the nodes in the cluster. To do that, there were/are a few options : 1) use raw disk devices that are shared, through SCSI, FC, or iSCSI 2) use a network filesystem (NFS) 3) use a cluster filesystem(CFS) which basically gives you a filesystem that's coherent across all nodes using shared disks. It is sort of (but not quite) combining option 1 and 2 except that you don't do network access to the files, the files are effectively locally visible as if it was a local filesystem. So OCFS (Oracle Cluster FileSystem) on Windows was born. Since Linux was becoming a very important and popular platform, we decided that we would also make this available on Linux and thus the porting of OCFS/Windows started. The first version of OCFS was really primarily focused on replacing the use of Raw devices with a simple filesystem that lets you create files and provide direct IO to these files to get basically native raw disk performance. The filesystem was not designed to be fully POSIX compliant and it did not have any where near good/decent performance for regular file create/delete/access operations. Cache coherency was easy since it was basically always direct IO down to the disk device and this ensured that any time one issues a write() command it would go directly down to the disk, and not return until the write() was completed. Same for read() any sort of read from a datafile would be a read() operation that went all the way to disk and return. We did not cache any data when it came down to Oracle data files. So while OCFS worked well for that, since it did not have much of a normal filesystem feel, it was not something that could be submitted to the kernel mail list for inclusion into Linux as another native linux filesystem (setting aside the Windows porting code ...) it did its job well, it was very easy to configure, node membership was simple, locking was disk based (so very slow but it existed), you could create regular files and do regular filesystem operations to a certain extend but anything that was not database data file related was just not very useful in general. Logfiles ok, standard filesystem use, not so much. Up to this point, all the work was done, at Oracle, by Oracle developers. Once OCFS (1) was out for a while and there was a lot of use in the database RAC world, many customers wanted to do more and were asking for features that you'd expect in a normal native filesystem, a real "general purposes cluster filesystem". So the team sat down and basically started from scratch to implement what's now known as OCFS2 (Oracle Cluster FileSystem release 2). Some basic criteria were : Design it with a real Distributed Lock Manager and use the network for lock negotiation instead of the disk Make it a Linux native filesystem instead of a native shim layer and a portable core Support standard Posix compliancy and be fully cache coherent with all operations Support all the filesystem features Linux offers (ACL, extended Attributes, quotas, sparse files,...) Be modern, support large files, 32/64bit, journaling, data ordered journaling, endian neutral, we can mount on both endian /cross architecture,.. Needless to say, this was a huge development effort that took many years to complete. A few big milestones happened along the way... OCFS2 was development in the open, we did not have a private tree that we worked on without external code review from the Linux Filesystem maintainers, great folks like Christopher Hellwig reviewed the code regularly to make sure we were not doing anything out of line, we submitted the code for review on lkml a number of times to see if we were getting close for it to be included into the mainline kernel. Using this development model is standard practice for anyone that wants to write code that goes into the kernel and having any chance of doing so without a complete rewrite or.. shall I say flamefest when submitted. It saved us a tremendous amount of time by not having to re-fit code for it to be in a Linus acceptable state. Some other filesystems that were trying to get into the kernel that didn't follow an open development model had a lot harder time and a lot harsher criticism. March 2006, when Linus released 2.6.16, OCFS2 officially became part of the mainline kernel, it was accepted a little earlier in the release candidates but in 2.6.16. OCFS2 became officially part of the mainline Linux kernel tree as one of the many filesystems. It was the first cluster filesystem to make it into the kernel tree. Our hope was that it would then end up getting picked up by the distribution vendors to make it easy for everyone to have access to a CFS. Today the source code for OCFS2 is approximately 85000 lines of code. We made OCFS2 production with full support for customers that ran Oracle database on Linux, no extra or separate support contract needed. OCFS2 1.0.0 started being built for RHEL4 for x86, x86-64, ppc, s390x and ia64. For RHEL5 starting with OCFS2 1.2. SuSE was very interested in high availability and clustering and decided to build and include OCFS2 with SLES9 for their customers and was, next to Oracle, the main contributor to the filesystem for both new features and bug fixes. Source code was always available even prior to inclusion into mainline and as of 2.6.16, source code was just part of a Linux kernel download from kernel.org, which it still is, today. So the latest OCFS2 code is always the upstream mainline Linux kernel. OCFS2 is the cluster filesystem used in Oracle VM 2 and Oracle VM 3 as the virtual disk repository filesystem. Since the filesystem is in the Linux kernel it's released under the GPL v2 The release model has always been that new feature development happened in the mainline kernel and we then built consistent, well tested, snapshots that had versions, 1.2, 1.4, 1.6, 1.8. But these releases were effectively just snapshots in time that were tested for stability and release quality. OCFS2 is very easy to use, there's a simple text file that contains the node information (hostname, node number, cluster name) and a file that contains the cluster heartbeat timeouts. It is very small, and very efficient. As Sunil Mushran wrote in the manual : OCFS2 is an efficient, easily configured, quickly installed, fully integrated and compatible, feature-rich, architecture and endian neutral, cache coherent, ordered data journaling, POSIX-compliant, shared disk cluster file system. Here is a list of some of the important features that are included : Variable Block and Cluster sizes Supports block sizes ranging from 512 bytes to 4 KB and cluster sizes ranging from 4 KB to 1 MB (increments in power of 2). Extent-based Allocations Tracks the allocated space in ranges of clusters making it especially efficient for storing very large files. Optimized Allocations Supports sparse files, inline-data, unwritten extents, hole punching and allocation reservation for higher performance and efficient storage. File Cloning/snapshots REFLINK is a feature which introduces copy-on-write clones of files in a cluster coherent way. Indexed Directories Allows efficient access to millions of objects in a directory. Metadata Checksums Detects silent corruption in inodes and directories. Extended Attributes Supports attaching an unlimited number of name:value pairs to the file system objects like regular files, directories, symbolic links, etc. Advanced Security Supports POSIX ACLs and SELinux in addition to the traditional file access permission model. Quotas Supports user and group quotas. Journaling Supports both ordered and writeback data journaling modes to provide file system consistency in the event of power failure or system crash. Endian and Architecture neutral Supports a cluster of nodes with mixed architectures. Allows concurrent mounts on nodes running 32-bit and 64-bit, little-endian (x86, x86_64, ia64) and big-endian (ppc64) architectures. In-built Cluster-stack with DLM Includes an easy to configure, in-kernel cluster-stack with a distributed lock manager. Buffered, Direct, Asynchronous, Splice and Memory Mapped I/Os Supports all modes of I/Os for maximum flexibility and performance. Comprehensive Tools Support Provides a familiar EXT3-style tool-set that uses similar parameters for ease-of-use. The filesystem was distributed for Linux distributions in separate RPM form and this had to be built for every single kernel errata release or every updated kernel provided by the vendor. We provided builds from Oracle for Oracle Linux and all kernels released by Oracle and for Red Hat Enterprise Linux. SuSE provided the modules directly for every kernel they shipped. With the introduction of the Unbreakable Enterprise Kernel for Oracle Linux and our interest in reducing the overhead of building filesystem modules for every minor release, we decide to make OCFS2 available as part of UEK. There was no more need for separate kernel modules, everything was built-in and a kernel upgrade automatically updated the filesystem, as it should. UEK allowed us to not having to backport new upstream filesystem code into an older kernel version, backporting features into older versions introduces risk and requires extra testing because the code is basically partially rewritten. The UEK model works really well for continuing to provide OCFS2 without that extra overhead. Because the RHEL kernel did not contain OCFS2 as a kernel module (it is in the source tree but it is not built by the vendor in kernel module form) we stopped adding the extra packages to Oracle Linux and its RHEL compatible kernel and for RHEL. Oracle Linux customers/users obviously get OCFS2 included as part of the Unbreakable Enterprise Kernel, SuSE customers get it by SuSE distributed with SLES and Red Hat can decide to distribute OCFS2 to their customers if they chose to as it's just a matter of compiling the module and making it available. OCFS2 today, in the mainline kernel is pretty much feature complete in terms of integration with every filesystem feature Linux offers and it is still actively maintained with Joel Becker being the primary maintainer. Since we use OCFS2 as part of Oracle VM, we continue to look at interesting new functionality to add, REFLINK was a good example, and as such we continue to enhance the filesystem where it makes sense. Bugfixes and any sort of code that goes into the mainline Linux kernel that affects filesystems, automatically also modifies OCFS2 so it's in kernel, actively maintained but not a lot of new development happening at this time. We continue to fully support OCFS2 as part of Oracle Linux and the Unbreakable Enterprise Kernel and other vendors make their own decisions on support as it's really a Linux cluster filesystem now more than something that we provide to customers. It really just is part of Linux like EXT3 or BTRFS etc, the OS distribution vendors decide. Do not confuse OCFS2 with ACFS (ASM cluster Filesystem) also known as Oracle Cloud Filesystem. ACFS is a filesystem that's provided by Oracle on various OS platforms and really integrates into Oracle ASM (Automatic Storage Management). It's a very powerful Cluster Filesystem but it's not distributed as part of the Operating System, it's distributed with the Oracle Database product and installs with and lives inside Oracle ASM. ACFS obviously is fully supported on Linux (Oracle Linux, Red Hat Enterprise Linux) but OCFS2 independently as a native Linux filesystem is also, and continues to also be supported. ACFS is very much tied into the Oracle RDBMS, OCFS2 is just a standard native Linux filesystem with no ties into Oracle products. Customers running the Oracle database and ASM really should consider using ACFS as it also provides storage/clustered volume management. Customers wanting to use a simple, easy to use generic Linux cluster filesystem should consider using OCFS2. To learn more about OCFS2 in detail, you can find good documentation on http://oss.oracle.com/projects/ocfs2 in the Documentation area, or get the latest mainline kernel from http://kernel.org and read the source. One final, unrelated note - since I am not always able to publicly answer or respond to comments, I do not want to selectively publish comments from readers. Sometimes I forget to publish comments, sometime I publish them and sometimes I would publish them but if for some reason I cannot publicly comment on them, it becomes a very one-sided stream. So for now I am going to not publish comments from anyone, to be fair to all sides. You are always welcome to email me and I will do my best to respond to technical questions, questions about strategy or direction are sometimes not possible to answer for obvious reasons.

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• CodePlex Daily Summary for Sunday, November 13, 2011

  CodePlex Daily Summary for Sunday, November 13, 2011Popular ReleasesT.S.T. the T-SQL Test Tool: Version 1.8: Implement the Assert.Ignore API. Fix a bug: A test session is reported as passing if only the test session setup or test session teardown failed. Improve the text and xml output when test session setup/teardown are present. Allow users to customize the prefix "SQLTest_".VidCoder: 1.2.2: Updated Handbrake core to svn 4344. Fixed the 6-channel discrete mixdown option not appearing for AAC encoders. Added handling for possible exceptions when copying to the clipboard, added retries and message when it fails. Fixed issue with audio bitrate UI not appearing sometimes when switching audio encoders. Added extra checks to protect against reported crashes. Added code to upgrade encoding profiles on old queued items.Dynamic PagedCollection (Silverlight / WPF Pagination): PagedCollection: All classes which facilitate your dynamic pagination in Silverlight or WPF !Media Companion: MC 3.422b Weekly: Ensure .NET 4.0 Full Framework is installed. (Available from http://www.microsoft.com/download/en/details.aspx?id=17718) Ensure the NFO ID fix is applied when transitioning from versions prior to 3.416b. (Details here) TV Show Resolutions... Made the TV Shows folder list sorted. Re-visibled 'Manually Add Path' in Root Folders. Sorted list to process during new tv episode search Rebuild Movies now processes thru folders alphabetically Fix for issue #208 - Display Missing Episodes is not popu...DotSpatial: DotSpatial Release Candidate 1 (1.0.823): Supports loading extensions using System.ComponentModel.Composition. DemoMap compiled as x86 so that GDAL runs on x64 machines. How to: Use an Assembly from the WebBe aware that your browser may add an identifier to downloaded files which results in "blocked" dll files. You can follow the following link to learn how to "Unblock" files. Right click on the zip file before unzipping, choose properties, go to the general tab and click the unblock button. http://msdn.microsoft.com/en-us/library...XPath Visualizer: XPathVisualizer v1.3 Latest: This is v1.3.0.6 of XpathVisualizer. This is an update release for v1.3. These workitems have been fixed since v1.3.0.5: 7429 7432 7427MSBuild Extension Pack: November 2011: Release Blog Post The MSBuild Extension Pack November 2011 release provides a collection of over 415 MSBuild tasks. A high level summary of what the tasks currently cover includes the following: System Items: Active Directory, Certificates, COM+, Console, Date and Time, Drives, Environment Variables, Event Logs, Files and Folders, FTP, GAC, Network, Performance Counters, Registry, Services, Sound Code: Assemblies, AsyncExec, CAB Files, Code Signing, DynamicExecute, File Detokenisation, GU...CODE Framework: 4.0.11110.0: Various minor fixes and tweaks.Extensions for Reactive Extensions (Rxx): Rxx 1.2: What's NewRelated Work Items Please read the latest release notes for details about what's new. Content SummaryRxx provides the following features. See the Documentation for details. Many IObservable<T> extension methods and IEnumerable<T> extension methods. Many useful types such as ViewModel, CommandSubject, ListSubject, DictionarySubject, ObservableDynamicObject, Either<TLeft, TRight>, Maybe<T> and others. Various interactive labs that illustrate the runtime behavior of the extensio...Player Framework by Microsoft: HTML5 Player Framework 1.0: Additional DownloadsHTML5 Player Framework Examples - This is a set of examples showing how to setup and initialize the HTML5 Player Framework. This includes examples of how to use the Player Framework with both the HTML5 video tag and Silverlight player. Note: Be sure to unblock the zip file before using. Note: In order to test Silverlight fallback in the included sample app, you need to run the html and xap files over http (e.g. over localhost). Silverlight Players - Visit the Silverlig...MapWindow 4: MapWindow GIS v4.8.6 - Final release - 64Bit: What’s New in 4.8.6 (Final release)A few minor issues have been fixed What’s New in 4.8.5 (Beta release)Assign projection tool. (Sergei Leschinsky) Projection dialects. (Sergei Leschinsky) Projections database converted to SQLite format. (Sergei Leschinsky) Basic code for database support - will be developed further (ShapefileDataClient class, IDataProvider interface). (Sergei Leschinsky) 'Export shapefile to database' tool. (Sergei Leschinsky) Made the GEOS library static. geos.dl...Facebook C# SDK: v5.3.2: This is a RTW release which adds new features and bug fixes to v5.2.1. Query/QueryAsync methods uses graph api instead of legacy rest api. removed dependency from Code Contracts enabled Task Parallel Support in .NET 4.0+ (experimental) added support for early preview for .NET 4.5 (binaries not distributed in codeplex nor nuget.org, will need to manually build from Facebook-Net45.sln) added additional method overloads for .NET 4.5 to support IProgress<T> for upload progress added ne...Delete Inactive TS Ports: List and delete the Inactive TS Ports: UPDATEAdded support for windows 2003 servers and removed some null reference errors when the registry key was not present List and delete the Inactive TS Ports - The InactiveTSPortList.EXE accepts command line arguments The InactiveTSPortList.Standalone.WithoutPrompt.exe runs as a standalone exe without the need for any command line arguments.ClosedXML - The easy way to OpenXML: ClosedXML 0.60.0: Added almost full support for auto filters (missing custom date filters). See examples Filter Values, Custom Filters Fixed issues 7016, 7391, 7388, 7389, 7198, 7196, 7194, 7186, 7067, 7115, 7144Microsoft Research Boogie: Nightly builds: This download category contains automatically released nightly builds, reflecting the current state of Boogie's development. We try to make sure each nightly build passes the test suite. If you suspect that was not the case, please try the previous nightly build to see if that really is the problem. Also, please see the installation instructions.GoogleMap Control: GoogleMap Control 6.0: Major design changes to the control in order to achieve better scalability and extensibility for the new features comming with GoogleMaps API. GoogleMap control switched to GoogleMaps API v3 and .NET 4.0. GoogleMap control is 100% ScriptControl now, it requires ScriptManager to be registered on the pages where and before it is used. Markers, polylines, polygons and directions were implemented as ExtenderControl, instead of being inner properties of GoogleMap control. Better perfomance. Better...WabbitStudio Z80 Software Tools: WabbitCode Mac 2.1: WabbitCode for the Mac version 2.1. You need 10.7 (Lion) to run this. There won't be any further releases for older versions of OS X.Shell Sort Web service and Application: Shell sort Web service and application: Shell Sort WebserviceSharePoint Backup Augmentation Cmdlets: SharePointBAC Technology Preview: This release is purely an opportunity for administrators who live on the bleeding-edge to "kick the tires." Only two cmdlets are available: Get-SPBackupCatalog and Remove-SPBackupCatalog. Both of these cmdlets are fully functional and documented in their current form, but the cmdlets have seen little testing and real-world use thus far. The code, capabilities, and reliability of this project will evolve in the weeks and months ahead, but for now you should avoid deploying these cmdlets to pro...WDTVHubGen - Adds Metadata, thumbnails and subtitles to WDTV Live Hubs: V2.1: Version 2.1 (click on the right) this uses V4.0 of .net Version 2.1 adds the following features: (apologize if I forget some, added a lot of little things) Manual Lookup with TV or Movie (finally huh!), you can look up a movie or TV episode directly, you can right click on anythign, and choose manual lookup, then will allow you to type anything you want to look up and it will assign it to the file you right clicked. No Rename: a very popular request, this is an option you can set so that t...New ProjectsBTG - Bilateral Tower Guardians: BIEN TA GROTTEc# Extended Link List: The ExtendedLinkList Graffiti CMS Widget is a C# port of an existing widget by Curt C at http://www.codeplex.com/ExtendedLinkListCodePubs: codepubs DegradingLoad: DegradingLoad will attempt to load a process serverside async; if it takes too long it will "degrade" to using clientside ajax to retrieve the result without blocking the main page contentDino: Dino is a simple ORM wrapper framework that provides a consistent set of interfaces for working with a variety of ORMs in a single Unit of Work. Dino is built to be extremely lightweight, with built in support for abstracting away some of the intricicies of using various ORMs.Elenoire: Elenoire is a live bot assistant for everyday that takes a appointment and note for you, the bot work when you are not present on messenger. Fontus: Fontus è un sistema centralizzato per l’erogazione di contenuti informativi. Il sistema Fontus si basa su un meccanismo di plug-in per rendere l’insieme delle fonti estendibile. FoolFish.CodeBase: implement your especial ideas...FullonSMS Desktop Client: Send free sms using fullonsms by this software to anywhere in India, supports grouping and contacts feature. Developed by Ayush PateriaInterface Interceptor: Allows you to filter and intercept interface methods.NBouncer: NBouncer is a Context Aware Validation framework without attributes for .NET 3.5 Winforms, WPF, Silverlight or Asp.NET MVCNetShips: Simple network battleship game for 2 players.Nhung Nai Website: phát tri?n Nhung Nai WebisteOpenCV2.2 Project template For Visual Studio 2010: The intension of the project is to make your life little easier if you use OpenCV2.2. As i couldn't find a project template for OpenCV, I decided to publish it on codeplex. Hope it will help at least some of you.Projeto de Compiladores: Projeto de Compiladores da Unicap 2011.2sejce2008: jce se course wiki and projects linksSharpener: Sharpener is a simple optimizer for .NET and Mono.Simple Live Screen: Simple Live Screen's target is to fasten screen transmits by using it's own protocol. This program is being developed in C#.Simple Note XML - ASP.NET User Control: Simple Note XML makes it easier for ASP.NET Developers to build lists. You'll no longer have to write things down. It's developed in ASP.NET 2.0 C#. SquadLead for Tasks - Community Edition: SquadLead Tasks Community Edition is a PostGreSQL based Task Management software for teams, with wonderful time and resource allocation abilities. Unlinke Gannt charting and dependency abilities, SquadLead gives a flexibility to create ad-hoc tasks with no dependencies and hence suits many different kind of projects in a versatile way. If you take care of dependencies, it takes care of helping you with identifying allocation loads, reports and graphs. Features Task Management and...Stanford db-class algorithms: The algorithms of the relational db theory, described in the introduction to databases Stanford class (www.db-class.org).tfsProjectInitialiser: After creating a Team Project, load the initial state of the project - complete with Areas, Iterations, Work Items - quickly and easily. I am on my one on this so far, so any help or contribution would be appreciated.

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• CodePlex Daily Summary for Sunday, October 30, 2011

  CodePlex Daily Summary for Sunday, October 30, 2011Popular ReleasesKoober: Koober - The Ebook Creator 0.2: The official release of Koober as Open source. Koober is a ebook creator for Windows, and Koob Reader is the reader.?????????????: ??????????????: ??????????????VidCoder: 1.2.0: Updated to HandBrake svn 4311. Refactored to read in list of encoders from HandBrake itself. Added ffaac, FLAC audio and ffmpeg2 video. Reworked audio encoding UI: removed grid and gave each encoding more vertical space. Added audio quality targeting and compression. Added status messages. Added messages for a few events (encode start/stop, playing a preview clip, update available, update download finished). Made source and destination path UI elements smarter about what parts they cut ...patterns & practices: Enterprise Library Contrib: Enterprise Library Contrib - 5.0 (Oct 2011): This release of Enterprise Library Contrib is based on the Microsoft patterns & practices Enterprise Library 5.0 core and contains the following: Common extensionsTypeConfigurationElement<T> - A Polymorphic Configuration Element without having to be part of a PolymorphicConfigurationElementCollection. AnonymousConfigurationElement - A Configuration element that can be uniquely identified without having to define its name explicitly. Data Access Application Block extensionsMySql Provider - ...Network Monitor Open Source Parsers: Network Monitor Parsers 3.4.2748: The Network Monitor Parsers packages contain parsers for more than 400 network protocols, including RFC based public protocols and protocols for Microsoft products defined in the Microsoft Open Specifications for Windows and SQL Server. NetworkMonitor_Parsers.msi is the base parser package which defines parsers for commonly used public protocols and protocols for Microsoft Windows. In this release, NetowrkMonitor_Parsers.msi continues to improve quality and fix bugs. It has included the fo...Duckworth Lewis Professional Edition Calculator: DLcalc 3.0: DLcalc 3.0 can perform Duckworth/Lewis Professional Edition calculations 100% accurately. It also produces over-by-over and ball-by-ball PAR score tables.Folder Bookmarks: Folder Bookmarks 2.2.0.1: In this version: Custom Icons - now you can change the icons of the bookmarks. By default, whenever an image is added, the icon is automatically changed to a thumbnail of the picture. This can be turned off in the settings (Options... > Settings) Ability to remove items from the 'Recent' category Bugfixes - 'Choose' button in 'Edit Bookmark' now works Another bug fix: another problem in the 'Edit Bookmark' windowMedia Companion: MC 3.420b Weekly: Ensure .NET 4.0 Full Framework is installed. (Available from http://www.microsoft.com/download/en/details.aspx?id=17718) Ensure the NFO ID fix is applied when transitioning from versions prior to 3.416b. (Details here) Movies Fixed: Fanart and poster scraping issues TV Shows (Re)Added: Rebuild single show Fixed: Issue when shows are moved from original location Ability to handle " for actor nicknames Crash when episode name contains "<" (does not scrape yet) Clears fanart when switch...patterns & practices - Unity: Unity 3.0 for .NET4.5 Preview: The Unity 3.0.1026.0 Preview enables Unity to work on .NET 4.5 with both the WinRT and desktop profiles. The major changes include: Unity projects updated to target .NET 4.5. Dynamic build plans modified to use compiled lambda expressions instead of Reflection.Emit Converting reflection to use the new TypeInfo for reflection. Projects updated to work with the Microsoft Visual Studio 2011 Preview Notes/Known Issues: The Microsoft.Practices.Unity.UnityServiceLocator class cannot be use...Managed Extensibility Framework: MEF 2 Preview 4: Detailed information on this release is available on the BCL team blog.Image Converter: Image Converter 0.3: New Features: - English and German support Technical Improvements: - Microsoft All Rules using Code Analysis Planned Features for future release: 1. Unit testing 2. Command line interface 3. Automatic UpdatesAcDown????? - Anime&Comic Downloader: AcDown????? v3.6: ?? ● AcDown??????????、??????，??????????????????????，???????Acfun、Bilibili、???、???、???、Tucao.cc、SF???、?????80????，???????????、?????????。 ● AcDown???????????????????????????，???，???????????????????。 ● AcDown???????C#??，????.NET Framework 2.0??。?????"Acfun?????"。 ????32??64? Windows XP/Vista/7 ????????????? ??：????????Windows XP???,?????????.NET Framework 2.0???(x86)?.NET Framework 2.0???(x64)，?????"?????????"??? ??????????????，??????????： ??"AcDown?????"????????? ?? v3.6?? ??“????”...Path Copy Copy: 8.0: New version that mostly adds lots of requested features: 11340 11339 11338 11337 This version also features a more elaborate Settings UI that has several tabs. I tried to add some notes to better explain the use and purpose of the various options. The Path Copy Copy documentation is also on the way, both to explain how to develop custom plugins and to explain how to pre-configure options if you're a network admin. Stay tuned.MVC Controls Toolkit: Mvc Controls Toolkit 1.5.0: Added: The new Client Blocks feaure of Views A new "move" js method for the TreeViews The NewHtmlCreated js event to the DataGrid Improved the ChoiceList structure that now allows also the selection list of a dropdown to be chosen with a lambda expression Improved the AcceptViewHintAttribute controller filter. Now a client can specify not only the name of a View or Partial View it prefers, but also to receive just the rough data in Json format. Now the the SMinimum and SMaximum par...Free SharePoint Master Pages: Buried Alive (Halloween) Theme: Release Notes *Created for Halloween, you will find theme file, custom css file and images. *Created by Al Roome @AlstarRoome Features: Custom styling for web part Custom background *Screenshot https://s3.amazonaws.com/kkhipple/post/sharepoint-showcase-halloween.pngDevForce Application Framework: DevForce AF 2.0.3 RTW: PrerequisitesWPF 4.0 Silverlight 4.0 DevForce 2010 6.1.3.1 Download ContentsDebug and Release Assemblies API Documentation Source code License.txt Requirements.txt Release HighlightsNew: EventAggregator event forwarding New: EntityManagerInterceptor<T> to intercept EntityManger events New: IHarnessAware to allow for ViewModel setup when executed inside of the Development Harness New: Improved design time stability New: Support for add-in development New: CoroutineFns.To...NicAudio: NicAudio 2.0.5: Minor change to accept special DTS stereo modes (LtRt, AB,...)NDepend TFS 2010 integration: version 0.5.0 beta 1: Only the activity and the VS plugin are avalaible right now. They basically work. Data types that are logged into tfs reports are subject to change. This is no big deal since data is not yet sent into the warehouse.Windows Azure Toolkit for Windows Phone: Windows Azure Toolkit for Windows Phone v1.3.1: Upgraded Windows Azure projects to Windows Azure Tools for Microsoft Visual Studio 2010 1.5 – September 2011 Upgraded the tools tools to support the Windows Phone Developer Tools RTW Update SQL Azure only scenarios to use ASP.NET Universal Providers (through the System.Web.Providers v1.0.1 NuGet package) Changed Shared Access Signature service interface to support more operations Refactored Blobs API to have a similar interface and usage to that provided by the Windows Azure SDK Stor...DotNetNuke® FAQ: 05.00.00: FAQ (Frequently Asked Questions) 05.00.00 will work for any DNN version 5.6.1 and up. It is the first version which is rewritten in C#. The scope of this update is to fix all known issues and improve user interface. Please review and rate this release... (stars are welcome)BUG FIXESManage Categories button text was not localized Edit/Add FAQ Entry: button text was not localized ENHANCEMENTSAdded an option to select the control for category display: Listbox with checkboxes (flat category ...New ProjectsalphaCards: Digitale LernkarteiBinary Code Interpreter: The Binary Code Interpreter is a small and funny programming languaage. This interpreter works a bit like a Turing Machine.Buscar ciudades: This is the source code for the application "Buscar ciudades" published in the Windows Phone Marketplace. CamOnWeb - Componente para WebCam: Este projeto tem como objetivo o desenvolvimento um componente para captura e exibição de videos da webcam. Compare.Net: Compare.Net is a configurable application to compare and reconclie from different sources. C# WPF applcation targeting .Net 4CSGame: Academic project for our studies. Subject "Client -server technology"curbside: curbsideDanish Language Pack for Community Server: Danish Language Packs for Community Server 2.1 and 2007. At its inception, this project contains quite incomplete translations to Danish. This project provides a common resource where all interested parties can gradually improve on this language pack. Please join to improve the contents. The source code tree contains two major folders: One for Community Server 2.1 and one for Community Server 2007.Dependency Variable Lib: ??????????????????、?????????????????????。（???????、?????????????ｗ） ???、「??×??＝??」???????????????、????????、????????、???「??×??」????????????????????????????????????。 FreedBack: FreedBack allows you to quickly and easily embed a configurable feedback form into any web application. It can be a standalone application that you install and deploy, then embed a bit of script into existing apps to implement feedback, or you can make it part of your MVC App.Hageveld - NieuwsModule (Chris' Tutorial: A news article manager made for educational purposes.Idea Resto: Aplicación para restaurantes.jqgridmvcgeneration: codesmith template that creates js, html and asp.net mvc server side json server for a jqgrid -based table on a arbitratrary database table. The code includes pagination and server side sorting. Jqgrid is a great jquery extension that provides an ajax-enabled fully customizable interactive table based on server side data. However, the actual coding can be a bit tedious and cryptic. This project provides a template base approach that basically performs two tasks: 1. creates a client si...MyClassMapper: A simple configurable classmapper for mapping ClassA to ClassB and vice versa, the ideas are borrowed from the Dozer project (http://dozer.sourceforge.net). Most code is based on 'Dynamic Access' code from Hongju Cao <hjcao_wei@hotmail.com> (All that code is located in the "DynamicAccess" sub-directory from the project.)NavigateTo Providers: This project is a collection of NavigateTo providers for Visual Studio 2010. NObsidian: A proxy component to access Obisidian Portal API from .NetNSession: The objective of this project is to allow ASP Classic to access ASP.NET out-of-process session stores in the same way that ASP.NET accesses them, and thus share the session state with ASP.NET.NTextile: NTextile is a lightweight, humane web compatible markup generator. It generates valid XHTML output using simple easy to remember conventions and text characters (a.k.a modifiers), to markup plain text. NTextile is especially useful to provide quick and valid markup for .NET web applications. For e.g. wikis, blogs, online forums, content management systems etc. This project was inspired by Dean Allen’s original Textile features, as included in the Textpattern content management application. T...OpenTasksBehaviorsLibrary for Windows Phone: Open Tasks Behavior for Windows Phone *OpenWebBrowserTask *OpenMediaLauncherTaskPowerShell Cmdlet Sample: PowerShell Cmdlet SamplePrismEx: PrismEx is a library of helpers and extension methods to allow developers to more easily develop and test Prism applications. QuickDelete: A Windows Explorer add-on to delete files and folders very quickly, much more so than the usual Explorer command. Works on Windows XP or later. Currently in EXPERIMENTAL state. No releases have been produced yet.Quiz Module for DotNetNuke: This is a module that allows you to quickly and easily provide a quiz that can be taken by the visitors on your DotNetNuke website.RaptorDB - The Key Value Store: Smallest, fastest embedded nosql persisted dictionary using b+tree or MurMur hash indexing. (Now with Hybrid WAH bitmap indexes)Rockin CMS-LMS Combo: RockinCmsLms Combo provides a great way for users to build their content and training sites with one great tool. It will be developed with C# 4.0-4.5, Silverlight, JQuery, and ASP.Net and MVC 3.0 with Razor. This project will demonstrate how to use todays technologies to build solutions that last. We may have 2 versions - one with a local db and one with a Windows Azure storage solution. Suggest using the Web Platform Installer to get all of the components.SandKeeper - Time Tracking Addin for Outlook 2010 tasks: SandKeeper is an Outlook Addin that enables you to track time for your tasks.Share: Share is a new web-based content management system. For more information about this project, please visit http://blog.aphysoft.com.SharePoint 2010 ViewEdit Group By Content Type: A simple project that injects JavaScript into the ribbon bar area to add "Content Type" as a choice on the ViewEdit.aspx page. With this, users can once again create views that group by Content Type without having to use SharePoint Designer 2010.Simple Merge Sort: This is a simple implementation of Merge-Sort, using to sort an Array of Integers.UKag: Unity3D?Kr2/KAG3??moduleUsingLinq: TestUtec Logger: Utec Logger is meant to be used the Turbo XS UTEC and UTEC Delta. It is simply a data logger application, it will auto logged based on pre defined conditionals. It also takes this information and displays it in a two dimensional table, averaging the values appropriately to ease of log analysis.WOXalizer: Fork of WOX project. http://woxserializer.sourceforge.net/Zeta Backup Validator: A small .NET 3.5 console application that helps you verifying whether your backups succeed by checking files and folders with various configurable rules (folder size, file age, etc.).Zeta Links: A web application for generating and measuring shortcut hyperlinks, similar to bit.ly.Zombie Slayer v1.0: Zombie Slayer v1.0 is an action first person shooter where players can try and survive a never-ending wave of zombies for as long as they can while a timer keeps track of how long they survived and posts times online from longest to shortest.?????????????: ??????????????????，????。

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