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  • MS Access to sql server searching

    - by malou17
    How to use this code if we are going to use sql server database becaUSE in this code we used MS Access as the database private void btnSearch_Click(object sender, System.EventArgs e) { String pcode = txtPcode.Text; int ctr = productsDS1.Tables[0].Rows.Count; int x; bool found = false; for (x = 0; x<ctr; x++) { if (productsDS1.Tables[0].Rows[x][0].ToString() == pcode) { found = true; break; } } if (found == true) { txtPcode.Text = productsDS1.Tables[0].Rows[x][0].ToString(); txtDesc.Text = productsDS1.Tables[0].Rows[x][1].ToString(); txtPrice.Text = productsDS1.Tables[0].Rows[x][2].ToString(); } else { MessageBox.Show("Record Not Found"); } private void btnNew_Click(object sender, System.EventArgs e) { int cnt = productsDS1.Tables[0].Rows.Count; string lastrec = productsDS1.Tables[0].Rows[cnt][0].ToString(); int newpcode = int.Parse(lastrec) + 1; txtPcode.Text = newpcode.ToString(); txtDesc.Clear(); txtPrice.Clear(); txtDesc.Focus(); here's the connectionstring Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Registry Path=;Jet OLEDB:Database Locking Mode=0;Data Source="J:\2009-2010\1st sem\VC#\Sample\WindowsApplication_Products\PointOfSales.mdb"

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  • Granite DS Actionscript Code Generation Ant cannot find class error

    - by Roaders
    I am trying to get my Ant build to run the granite DS Actionscript code generation task and am running into some problems. At the moment I am getting this error: BUILD FAILED C...\build.xml:62: Could not load Java class file: SampleDTOOne.class So the .class files are obviously being found. I am not however sure if this error means that the it cannot load the .class file or that it cannot find the actual java source code. My Ant task definition looks like this: <classpath> <pathelement location="C.../src/packages/" /> </classpath> <fileset dir="${base.build.dir}/jc/classes/gpbit/packageName"> <include name="*.class" /> </fileset> </gas3> I have tried many different values for the classpath but cannot get anythign to work. I do not like the path that I am using to find the .class files but again at the moment this is the only one I can get to work. None of the variables seem to make it any easier to get to this location. The fileset is definitely working as it definitely found the .clas files to include the name in the error message. More detailed error message: [gas3] Using output dir: C...trunk\plugin\build/etc/src/as3 [gas3] Using classpath: C...\trunk\plugin\src\packages [gas3] Loading all Java classes referenced by inner fileset(s) { [gas3] java.lang.ClassNotFoundException: SampleDTOOne [gas3] at org.apache.tools.ant.AntClassLoader.findClassInComponents(AntClassLoader.java:1361) any help much appreciated

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  • PowerShell PSCX Read-Archive: Cannot bind parameter... problem

    - by Robert
    I'm running across a problem I can't seem to wrap my head around using the Read-Archive cmdlet available via PowerShell Community Extensions (v2.0.3782.38614). Here is a cut down sample used to exhibit the problem I'm running into: $mainPath = "p:\temp" $dest = Join-Path $mainPath "ps\CenCodes.zip" Read-Archive -Path $dest -Format zip Running the above produces the following error: Read-Archive : Cannot bind parameter 'Path'. Cannot convert the "p:\temp\ps\CenCodes.zip" value of type "System.String" to type "Pscx.IO.PscxPathInfo". At line:3 char:19 + Read-Archive -Path <<<< $dest -Format zip + CategoryInfo : InvalidArgument: (:) [Read-Archive], ParameterBindingException + FullyQualifiedErrorId : CannotConvertArgumentNoMessage,Pscx.Commands.IO.Compression.ReadArchiveCommand If I do not use Join-Path to build the path passed to Read-Archive it works, as in this example: $mainPath = "p:\temp" $path = $mainPath + "\ps\CenCodes.zip" Read-Archive -Path $path -Format zip Output from above: ZIP Folder: CenCodes.zip#\ Index LastWriteTime Size Ratio Name ----- ------------- ---- ----- ---- 0 6/17/2010 2:03 AM 3009106 24.53 % CenCodes.xls Even more confusing is if I compare the two variables passed as the Path argument in the two Read-Archive samples above, they seem identical: This... Write-Host "dest=$dest" Write-Host "path=$path" Write-Host ("path -eq dest is " + ($dest -eq $path).ToString()) Outputs... dest=p:\temp\ps\CenCodes.zip path=p:\temp\ps\CenCodes.zip path -eq dest is True Anyone have any ideas as to why the first sample gripes but the second one works fine?

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  • How to disable selective keys on the keyboard?

    - by Vilx-
    I'd like to write an application which disables certain keys on the keyboard while it's working. More specifically I'm interested in keys that might make the application loose focus (like ALT+TAB, WinKey, Ctrl+Shift+Esc, etc.) The need for this is has to do with babies/animals bashing wildly at the keyboard. :) My first idea was to use SetWindowsHookEx, however I ran into a problem. Since I need a global hook, the procedure would have to reside in a .DLL which would get injected in all active applications. But a .DLL can be either 64-bit or 32-bit, not both. And on a 64-bit system there are both types of applications. I guess then that I must write two copies of the hook .DLL - one for 32-bit and the other for 64-bit. And then I'd also have to launch two copies of the application as well, because the application first has to load the DLL itself before it can pass it on to SetWindowsHookEx(). Sounds pretty clumsy and awkward. Is there perhaps a better way? Or maybe I've misunderstood something?

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  • Parallel version of loop not faster than serial version

    - by Il-Bhima
    I'm writing a program in C++ to perform a simulation of particular system. For each timestep, the biggest part of the execution is taking up by a single loop. Fortunately this is embarassingly parallel, so I decided to use Boost Threads to parallelize it (I'm running on a 2 core machine). I would expect at speedup close to 2 times the serial version, since there is no locking. However I am finding that there is no speedup at all. I implemented the parallel version of the loop as follows: Wake up the two threads (they are blocked on a barrier). Each thread then performs the following: Atomically fetch and increment a global counter. Retrieve the particle with that index. Perform the computation on that particle, storing the result in a separate array Wait on a job finished barrier The main thread waits on the job finished barrier. I used this approach since it should provide good load balancing (since each computation may take differing amounts of time). I am really curious as to what could possibly cause this slowdown. I always read that atomic variables are fast, but now I'm starting to wonder whether they have their performance costs. If anybody has some ideas what to look for or any hints I would really appreciate it. I've been bashing my head on it for a week, and profiling has not revealed much.

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  • unable to compile a servlet in ubuntu

    - by codeomnitrix
    I am newbie to j2ee. I have download and installed j2eesdk-1_4_03-linux.bin in my ubuntu 10.04 distribution. and then i tried to code my first servlet in it as: import java.io.*; import javax.servelet.*; import javax.servelet.http.*; public class HowdyServelet extends HttpServelet{ public void doGet(HttpServeletRequest request, HttpServeletResponse response) throws IOException, ServeletException{ PrintWriter out = response.getWriter(); response.setContentType("text/html"); out.println("<html>"); out.println("<head><title>howdy</title></head>"); out.println("<body>"); out.println("<center><h1>Howdy</h1></center>"); out.println("</body>"); out.println("</html>"); } } and here are the environment variables i set after installation: 1. J2EE_HOME=/home/vinit/SUNWappserver 2. JAVA_HOME=/home/vinit/SUNWappserver/jdk 3. CLASSPATH=/home/vinit/SUNWappserver/lib and now i tried to compile the servlet using javac HowdyServelet.java But i got following errors: HowdyServelet.java:2: package javax.servelet does not exist import javax.servelet.*; ^ HowdyServelet.java:3: package javax.servelet.http does not exist import javax.servelet.http.*; ^ HowdyServelet.java:5: cannot find symbol symbol: class HttpServelet public class HowdyServelet extends HttpServelet{ ^ HowdyServelet.java:6: cannot find symbol symbol : class HttpServeletRequest location: class HowdyServelet public void doGet(HttpServeletRequest request, HttpServeletResponse response) throws IOException, ServeletException{ ^ HowdyServelet.java:6: cannot find symbol symbol : class HttpServeletResponse location: class HowdyServelet public void doGet(HttpServeletRequest request, HttpServeletResponse response) throws IOException, ServeletException{ ^ HowdyServelet.java:6: cannot find symbol symbol : class ServeletException location: class HowdyServelet public void doGet(HttpServeletRequest request, HttpServeletResponse response) throws IOException, ServeletException{ ^ 6 errors So how to compile this servlet. Thanks in advance.

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  • How to make active services highly available?

    - by Jader Dias
    I know that with Network Load Balancing and Failover Clusteringwe can make passive services highly available. But what about active apps? Example: One of my apps retrieves some content from a external resource in a fixed interval. I have imagined the following scenarios: Run it in a single machine. Problem: if this instance falls, the content won't be retrieved Run it in each machine of the cluster. Problem: the content will be retrieved multiple times Have it in each machine of the cluster, but run it only in one of them. Each instance will have to check some sort of common resource to decide whether it its turn to do the task or not. When I was thinking about the solution #3 I have wondered what should be the common resource. I have thought of creating a table in the database, where we could use it to get a global lock. Is this the best solution? How does people usually do this? By the way it's a C# .NET WCF app running on Windows Server 2008

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  • "string" != "string"

    - by Misiur
    Hi. I'm doing some kind of own templates system. I want to change <title>{site('title')}</title> Into function "site" execution with parameter "title". Here's private function replaceFunc($subject) { foreach($this->func as $t) { $args = explode(", ", preg_replace('/\{'.$t.'\(\'([a-zA-Z,]+)\'\)\}/', '$1', $subject)); $subject = preg_replace('/\{'.$t.'\([a-zA-Z,\']+\)\}/', call_user_func_array($t, $args), $subject); } return $subject; } Here's site: function site($what) { global $db; $s = $db->askSingle("SELECT * FROM ".DB_PREFIX."config"); switch($what) { case 'title': return 'Title of page'; break; case 'version': return $s->version; break; case 'themeDir': return 'lolmao'; break; default: return false; } } I've tried to compare $what (which is for this case "title") with "title". MD5 are different. strcmp gives -1, "==", and "===" return false. What is wrong? ($what type is string. You can't change call_user_func_array into call_user_func, because later I'll be using multiple arguments)

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  • Poor DB4O performance - What am I doing wrong?

    - by Jon
    I read Rob Conery's post about Object databases and thought I'd give it a go. I have a class lets say Book with 15 properties mostly string, some int, one Datetime and 2 decimals. I used Rob's code to open the database file etc to test on a Winforms project not a Web project. So I did the following: for(int i = 0; i < 1000000; i++) { var Book = new Book(); //Assign variables s.Save(Book); } s.CommitChanges(); This took at least a couple of minutes. I then tried to retrieve all data to test speed: var spp = s.All<Passports>(); This one line was quick, however, then doing: sppp.Count() as well as a seperate test doing a foreach loop and incrementing a counter took a couple of minutes. This seems quite slow to me. Am I doing something wrong or am I expecting too much?

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  • Break a while loop without using If or Break

    - by Justin
    I need to create a program that uses while to find the volume of a cylinder. I need the while loop to break if the user inputs a negative value for the height. My code looks like this: double sentinel=1, h=1, v=0, r, count=0; // declares all variables needed final double PI=3.14159; boolean NotNegative=true; while(NotNegative){// && count==0){ // while both the height is positive AND the total times run is 0 System.out.print("Enter height (Use negative to exit): "); // has the user input the height h=Double.parseDouble(br.readLine()); sentinel=h; // save sentinel as the inputted height while(sentinel>0){ System.out.print("Enter radius: "); // have the user input the radius r=Double.parseDouble(br.readLine()); v=PI*(r*r)*h; // find the volume System.out.println("The volume is " + v); // print out the volume count++; // increase the count each time this runs NotNegative=true; sentinel=-1; } } Any help?

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  • Installing Ruby via rbenv fails

    - by Maximus S
    Problem: I installed ruby, but it is not recognized correctly. I'm following the deploying to VPS: https://github.com/railscasts/335-deploying-to-a-vps I am setting my server on ubuntu 12.04 LTS to deploy my rails app. I'm following the railscast on deploying to a VPS, and trying to install ruby through rbenv. It seemed everything was installed correctly, but when I tried to check the ruby version, it gave me errors. The following are the commands that I ran. deployer@max:~$ rbenv install 1.9.3-p125 Downloading yaml-0.1.4.tar.gz... -> http://cloud.github.com/downloads/sstephenson/ruby-build-download-mirror/36c852831d02cf90508c29852361d01b Installing yaml-0.1.4... Installed yaml-0.1.4 to /home/deployer/.rbenv/versions/1.9.3-p125 Downloading ruby-1.9.3-p125.tar.gz... -> http://cloud.github.com/downloads/sstephenson/ruby-build-download-mirror/e3ea86b9d3fc2d3ec867f66969ae3b92 Installing ruby-1.9.3-p125... Installed ruby-1.9.3-p125 to /home/deployer/.rbenv/versions/1.9.3-p125 Downloading rubygems-1.8.23.tar.gz... -> http://cloud.github.com/downloads/sstephenson/ruby-build-download-mirror/178b0ebae78dbb46963c51ad29bb6bd9 Installing rubygems-1.8.23... Installed rubygems-1.8.23 to /home/deployer/.rbenv/versions/1.9.3-p125 deployer@max:~$ rbenv global 1.9.3-p125 deployer@max:~$ ruby -v 'ruby' program can be found in the following packages: * ruby1.8 * ruby1.9.1 How do I solve this?

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  • Reading from a database located in the Program Files folder using ODBC

    - by Dabblernl
    We have an application that stores its database files in a subfolder of the Program Files directory. These files are redirected to the VirtualStore in Vista and Windows 7. We represent data from the database using Microsoft DataReports (VB6). So far so good. But we now want to use Crystal Reports XI to represent data from the database. Our idea is to NOT pass this data to CR from our program, but to have CR retreive it from the database using a a system DSN through ODBC. In this way we hope to present our users with more flexibility in designing their own reports. What we do want to ensure though is that these system DSNs are configured correctly when the user installs our program or when the program calls the Crystal Report. Is there a smart way to do this using System variables for instance, instead of having to write a routine that checks for OS-version, whether UAC is enabled on the OS, whether the write restrictions on the Program Files folder have been lifted, etc and then adapts he System DSN to point to either the C:\Program Files\OurApp\Data folder, or the C:\Users\User\AppData\VirtualStore\Program Files\OurApp\Data folder? Suggestions for an entirely different approach are welcome too!

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  • php (rar) i want to rar a folder using rar on Ubuntu (linux) by php (on dedi server) noob

    - by Steve
    hey guyz i want rar (not tar) my folder on my server by using php RAR RAR 3.93 Copyright (c) 1993-2010 Alexander Roshal 15 Mar 2010 Registered to my real name OS Ubuntu Release (Karmic) kernel linux 2.6.32.2-xxxx-grs-ipv4-32 Gnome 2.28.1 latest php an lighthttpd i have tried these things http://php.net/manual/en/function.escapeshellarg.php // may be wrong code http://php.net/manual/en/function.exec.php http://php.net/manual/en/function.shell-exec.php my command (working in ssh and nautilus script) rar a -m0 /where/file/will/saved/file_name.rar /location/ti/data/dir/datafolder php code $log=Shell_exec("rar a -m0 /where/file/will/saved/file_name.rar /location/ti/data/dir/datafolder"); echo $log; one method is left which i don't know how to use and its working on server that is by somefile_to_execute_command.sh i have to execute .sh file from php need to send some variables (command) and i tried this method can rar file with a script named RapidLeech but its rar from only its own files dir only :( but i want to do in different directories. Rapid Leech rar class http://paste2.org/p/791668 i m able run shell command with php (cp(copy),mv(move),ls(directory list),rm(remove aka delete)) but got failed to run rar i gives no output i also tried to given path rar and i used alot commands with php Shell_exec function and working like they work with ssh and i have tried almost 80 % method given on net and failed from last 3days i m over now plz help me i need php script file working plz reply if u have any info n code and experience about rar and this kinda :( problem i m 99% noob just used code mean search Google collect script make my own working thing (for personal use only) n now i m failed to rar folder and file :(( now plz provide me code plz don't talk in technical language because i m just reading my first php book (for dummies :D) mean noob and 0.1 plz help me as much u can thankx

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  • SoundChannel, removeEventHandler, AS3

    - by pixelGreaser
    Is there a better way to use the sound channel is AS3? This works, but I hate it when I tap the play button twice and it starts doubling. Please advise. var mySound:Sound = new Sound(); playButton.addEventListener (MouseEvent.CLICK, myPlayButtonHandler); var myChannel:SoundChannel = new SoundChannel(); function myPlayButtonHandler (e:MouseEvent):void { myChannel = mySound.play(); } stopButton.addEventListener(MouseEvent.CLICK, onClickStop); function onClickStop(e:MouseEvent):void{ myChannel.stop(); } /*-----------------------------------------------------------------*/ //global sound buttons, add instance of 'killswitch' and 'onswitch' to stage killswitch.addEventListener(MouseEvent.CLICK, clipKillSwitch); function clipKillSwitch(e:MouseEvent):void{ var transform1:SoundTransform=new SoundTransform(); transform1.volume=0; flash.media.SoundMixer.soundTransform=transform1; } onswitch.addEventListener(MouseEvent.CLICK, clipOnSwitch); function clipOnSwitch(e:MouseEvent):void{ var transform1_:SoundTransform=new SoundTransform(); transform1_.volume=1; flash.media.SoundMixer.soundTransform=transform1_; }

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  • Why is this attempt at a binary search crashing?

    - by Ian Campbell
    I am fairly new to the concept of a binary search, and am trying to write a program that does this in Java for personal practice. I understand the concept of this well, but my code is not working. There is a run-time exception happening in my code that just caused Eclipse, and then my computer, to crash... there are no compile-time errors here though. Here is what I have so far: public class BinarySearch { // instance variables int[] arr; int iterations; // constructor public BinarySearch(int[] arr) { this.arr = arr; iterations = 0; } // instance method public int findTarget(int targ, int[] sorted) { int firstIndex = 1; int lastIndex = sorted.length; int middleIndex = (firstIndex + lastIndex) / 2; int result = sorted[middleIndex - 1]; while(result != targ) { if(result > targ) { firstIndex = middleIndex + 1; middleIndex = (firstIndex + lastIndex) / 2; result = sorted[middleIndex - 1]; iterations++; } else { lastIndex = middleIndex + 1; middleIndex = (firstIndex + lastIndex) / 2; result = sorted[middleIndex - 1]; iterations++; } } return result; } // main method public static void main(String[] args) { int[] sortedArr = new int[] { 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29 }; BinarySearch obj = new BinarySearch(sortedArr); int target = sortedArr[8]; int result = obj.findTarget(target, sortedArr); System.out.println("The original target was -- " + target + ".\n" + "The result found was -- " + result + ".\n" + "This took " + obj.iterations + " iterations to find."); } // end of main method } // end of class BinarySearch

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  • How to eliminate duplicate nodes bases on values of multiple attributes?

    - by JayRaj
    Hello All, How can I eliminate duplicate nodes based on values of multiple (more than 1) attributes? Also the attribute names are passed as parameters to the stylesheet. Now I am aware of the Muenchian method of grouping that uses a <xsl:key> element. But I came to know that XSLT 1.0 does not allow paramters/variables in <xsl:key>. Is there another method(s) to achieve duplicate nodes removal? It is fine if it not as efficient as the Munechian method. Update from previus question: XML: <data id = "root"> <record id="1" operator1='xxx' operator2='yyy' operator3='zzz'/> <record id="2" operator1='abc' operator2='yyy' operator3='zzz'/> <record id="3" operator1='abc' operator2='yyy' operator3='zzz'/> <record id="4" operator1='xxx' operator2='yyy' operator3='zzz'/> <record id="5" operator1='xxx' operator2='lkj' operator3='tyu'/> <record id="6" operator1='xxx' operator2='yyy' operator3='zzz'/> <record id="7" operator1='abc' operator2='yyy' operator3='zzz'/> <record id="8" operator1='abc' operator2='yyy' operator3='zzz'/> <record id="9" operator1='xxx' operator2='yyy' operator3='zzz'/> <record id="10" operator1='rrr' operator2='yyy' operator3='zzz'/> </data>

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  • how to determine if a character vector is a valid numeric or integer vector

    - by Andrew Barr
    I am trying to turn a nested list structure into a dataframe. The list looks similar to the following (it is serialized data from parsed JSON read in using the httr package). myList <- list(object1 = list(w=1, x=list(y=0.1, z="cat")), object2 = list(w=2, x=list(y=0.2, z="dog"))) unlist(myList) does a great job of recursively flattening the list, and I can then use lapply to flatten all the objects nicely. flatList <- lapply(myList, FUN= function(object) {return(as.data.frame(rbind(unlist(object))))}) And finally, I can button it up using plyr::rbind.fill myDF <- do.call(plyr::rbind.fill, flatList) str(myDF) #'data.frame': 2 obs. of 3 variables: #$ w : Factor w/ 2 levels "1","2": 1 2 #$ x.y: Factor w/ 2 levels "0.1","0.2": 1 2 #$ x.z: Factor w/ 2 levels "cat","dog": 1 2 The problem is that w and x.y are now being interpreted as character vectors, which by default get parsed as factors in the dataframe. I believe that unlist() is the culprit, but I can't figure out another way to recursively flatten the list structure. A workaround would be to post-process the dataframe, and assign data types then. What is the best way to determine if a vector is a valid numeric or integer vector?

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  • Why slim reader/writer exclusive lock outperformance the shared one?

    - by Jichao
    I have tested the performance of slim reader/writer lock under windows 7 using the codefrom Windows Via C/C++. The result surprised me that the exclusive lock out performance the shared one. Here are the code and the result. unsigned int __stdcall slim_reader_writer_exclusive(void *arg) { //SRWLOCK srwLock; //InitializeSRWLock(&srwLock); for (int i = 0; i < 1000000; ++i) { AcquireSRWLockExclusive(&srwLock); g_value = 0; ReleaseSRWLockExclusive(&srwLock); } _endthreadex(0); return 0; } unsigned int __stdcall slim_reader_writer_shared(void *arg) { int b; for (int i = 0; i < 1000000; ++i) { AcquireSRWLockShared(&srwLock); //b = g_value; g_value = 0; ReleaseSRWLockShared(&srwLock); } _endthreadex(0); return 0; } g_value is a global int volatile variable. Could you kindly explain why this could happen?

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  • ViewController access data

    - by Giovanni Filaferro
    Today i would ask you if there is a way to call a method of another view controller just not initializing it or just how to get that viewController as a global variable declared in .h file. Help me please. I'm using a PageViewController and I have to use a method of the contentViewController alredy initialized. here I create my ViewControllers: - (void)createTheContent { NSLog(@"createTheContent"); pageController = nil; //[pageController removeFromParentViewController]; //[pageController awakeFromNib]; NSDictionary *options = [NSDictionary dictionaryWithObject:[NSNumber numberWithInteger:UIPageViewControllerSpineLocationMin] forKey: UIPageViewControllerOptionSpineLocationKey]; self.pageController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal options: options]; pageController.dataSource = self; [[pageController view] setFrame:CGRectMake(0, 0, 320, 365)]; initialViewController = [self viewControllerAtIndex:0]; NSMutableArray *viewControllers = [NSArray arrayWithObject:initialViewController]; [pageController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil]; [self addChildViewController:pageController]; [[self view] addSubview:[pageController view]]; [pageController didMoveToParentViewController:self]; } here are my propertys in .h file: contentViewController *initialViewController; } //Page View Controller Properties @property (strong, nonatomic) UIPageViewController *pageController; @property (strong, nonatomic) NSArray *pageContent; @property (strong, nonatomic) NSMutableArray *pageStrings; @property (strong, nonatomic) id dataObject;

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  • Understanding Symbols In Ruby

    - by Kezzer
    Despite reading this article, I'm still confused as to the representation of the data in memory when it comes to using symbols. If a symbol, two of them contained in different objects, exist in the same memory location, then how is it that they contain different values? I'd have expected the same memory location to contain the same value. As a quote from the link: Unlike strings, symbols of the same name are initialized and exist in memory only once during a session of ruby I just don't understand how it manages to differentiate the values contained in the same memory location. EDIT So let's consider the example: patient1 = { :ruby => "red" } patient2 = { :ruby => "programming" } patient1.each_key {|key| puts key.object_id.to_s} 3918094 patient2.each_key {|key| puts key.object_id.to_s} 3918094 patient1 and patient2 are both hashes, that's fine. :ruby however is a symbol. If we were to output the following: patient1.each_key {|key| puts key.to_s} Then what will be output? "red", or "programming"? FURTHER EDIT I'm still really quite confused. I'm thinking a symbol is a pointer to a value. Let's forget hashes for a second. The questions I have are; can you assign a value to a symbol? Is a symbol just a pointer to a variable with a value in it? If symbols are global, does that mean a symbol always points to one thing?

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  • C# parameters by reference and .net garbage collection

    - by Yarko
    I have been trying to figure out the intricacies of the .NET garbage collection system and I have a question related to C# reference parameters. If I understand correctly, variables defined in a method are stored on the stack and are not affected by garbage collection. So, in this example: public class Test { public Test() { } public int DoIt() { int t = 7; Increment(ref t); return t; } private int Increment(ref int p) { p++; } } the return value of DoIt() will be 8. Since the location of t is on the stack, then that memory cannot be garbage collected or compacted and the reference variable in Increment() will always point to the proper contents of t. However, suppose we have: public class Test { private int t = 7; public Test() { } public int DoIt() { Increment(ref t); return t; } private int Increment(ref int p) { p++; } } Now, t is stored on the heap as it is a value of a specific instance of my class. Isn't this possibly a problem if I pass this value as a reference parameter? If I pass t as a reference parameter, p will point to the current location of t. However, if the garbage collector moves this object during a compact, won't that mess up the reference to t in Increment()? Or does the garbage collector update even references created by passing reference parameters? Do I have to worry about this at all? The only mention of worrying about memory being compacted on MSDN (that I can find) is in relation to passing managed references to unmanaged code. Hopefully that's because I don't have to worry about any managed references in managed code. :)

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  • osx rvm ruby 1.8.7 nokogiri 1.4.1 - ERROR: Failed to build gem native extension.

    - by tommasop
    I'm stuck with this problem. cat ~/.rvm/gems/ruby-1.8.7-p249/gems/nokogiri-1.4.1/ext/nokogiri/mkmf.log Gives this errors (clipped) conftest.c:3: error: 'xmlParseDoc' undeclared (first use in this function) conftest.c:3: error: (Each undeclared identifier is reported only once conftest.c:3: error: for each function it appears in.) For several libraries which are found in the system. If I manually go into ~/.rvm/gems/ruby-1.8.7-p249/gems/nokogiri-1.4.1/ext/nokogiri/ And compile and install everything goes fine ruby extconf.rb make make install mkdir -p /Users/tommasop/.rvm/rubies/ruby-1.8.7-p249/lib/ruby/site_ruby/1.8/i686-darwin9.8.0/nokogiri /usr/bin/install -c -m 0755 nokogiri.bundle /Users/tommasop/.rvm/rubies/ruby-1.8.7-p249/lib/ruby/site_ruby/1.8/i686-darwin9.8.0/nokogiri except that on script/server: ? script/server --debugger => Booting Mongrel => Rails 2.3.5 application starting on http://0.0.0.0:3000 ./script/../config/../vendor/rails/railties/lib/rails/gem_dependency.rb:119:Warning: Gem::Dependency#version_requirements is deprecated and will be removed on or after August 2010. Use #requirement The following gems have native components that need to be built nokogiri You're running: ruby 1.8.7.249 at /Users/tommasop/.rvm/rubies/ruby-1.8.7-p249/bin/ruby rubygems 1.3.6 at /Users/tommasop/.rvm/gems/ruby-1.8.7-p249, /Users/tommasop/.rvm/gems/ruby-1.8.7-p249%global Run `rake gems:build` to build the unbuilt gems. Any help greatly appreciated!

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  • Loading a helper elsewhere than the autoload.php?

    - by drpcken
    I inherited a project and I'm cleaning up a bit and trying to finish it. I noticed that they used (or wrote) a breadcrumb helper. It is in my helpers folder and is named breadcrumb_helper.php It has a single function to build a breadcrumb menu with links and pass it to the view breadcrumbs.php. Here's the code: function show_breadcrumbs() { $ci =& get_instance(); $ci->load->helper('inflector'); $data = ''; //build breadcrumb and store in $data $this->load->view("breadcrumbs", $data) } I was trying to figure out how this helper worked and I checked the autoload.php but there is no reference to the helper in there. In face here is my autoload: $autoload['helper'] = array('url','asset','combine','navigation','form','portfolio','cookie','default'); This show_breadcrumbs() function is used quite a bit in some of my pages so I'm confused as to how its loading if it isn't in the autoloader. It is called like this in a few of my pages: <?=show_breadcrumbs()?> What am I missing? Why isn't this in my autoload? I even did a global search and couldn't find anywhere the helper is being loaded.

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  • Monotouch threads, GC, WCF

    - by cvista
    Hi This is a question about best practices i guess but it applies directly to my current MT project. I'm using WCF services to communicate with the server. To do this i do the following: services.MethodToCall(params); and the asynch: services.OnMethodToCallCompleted += delegate{ //do stuff and ting }; This can lead to issues if you're not careful in that variables defined within the scope of the asynch callback can sometimes be cleaned up by the gc and this can cause crashes. So - I am making it a practice to declare these outside of the scope of the callback unless I am 100% sure they are not needed. Now - when doing stuff and ting implies changing the ui - i wrap it all in an InvokeOnMainThread call. I guess wrapping everything in this would slow the main thread down and rubbish the point of having multi threads. Even though I'm being careful about all this i am still getting crashes and I have no idea why! I am certain it has something to do with threads, scope and all that. Now - the only thing I can think of outside of updating the UI that may need to happen inside of InvokeOnMainThread is that I have a singleton 'Database' class. This is based on the version 5 code from this thread http://www.yoda.arachsys.com/csharp/singleton.html So now if the service method returns data that needs to be added/updated to the Database class -I also wrap this inside an InvokeOnMainThread call. Still getting random crashes. So... My question is this: I am new to thick client dev - I'm coming from a web dev perspective where we don't need to worry about threads so much :) Aside from what I have mentioned -are there any other things I should be aware of? Is the above stuff correct? Or am i miss-understanding something? Cheers w://

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  • Netlogo: error when putting variable in table, only constants allowe??

    - by Chantal
    Hello, Currently I am working on a Netlogo program where I need to use nodes and links for vehicle routing problem. (links are called streets in the program) Here I have some practical problems of how to input variable linkspeed in a table with another node. Constants like 200 etc are fine. Online I found some examples where variables are used, but I do not know why I keep getting the following error: Expected a constant. (or why netlogo expects a constant) Here is the relevant piece of code: extensions [table] streets-own [linkspeed linktoll] nodes-own [netw] ;; In another piece of code linkspeed is assigned successfully to the links to cheapcalc ;; start conditions set costs very high 300000 ;; state 3 unsearched state 2 searching state 1 searched (for later purposes) ask nodes [ set i 0 set j count nodes set netw table:make while [i < j][ table:put netw (i) [3000000 3] set i (i + 1)]] set i 0 let k 0 ask node 35 ;; here i use node 35 as an example. ;; node 35 is connected to node 34, 36, 20 and 50 [table:put netw (35) [0 1] ;; node need to search costs to travel to itself ;; putting constants is ok. while [i < j] [ask my-links [ask both-ends [if (who != 35) [set color blue ;; set temp ([linkspeed] of street 35 who) ;; here my real goal is to put this in stat of i. but i is easier than linkspeed. table:put netw (who) [ i 2 ] ] ] ] set i (i + 1)] ] ;; next node for later, no it is just repetition of the same. end I hope somebody knows what is going on... Kind regards, Chantal

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