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  • Correct way to switch between UIView with ARC. My way leads to memory leaks :( (iOS)

    - by Andrei Golubev
    i use xcode 4.4 with ARC on.. I have dynamically created UIViews in the ViewController.m: UIView*myviews[10]; Then in the - (void)viewDidLoad function i fill each of it with pictures i need myviews[viewIndex] = [[UIView alloc]initWithFrame:myrec]; UIImage *testImg; UIImageView * testImgView; testImg = [UIImage imageNamed:[NSString stringWithFormat:@"imgarray%d.png", viewIndex]; testImgView.image = testImg; viewindex++; So all seems to be fine, when i want to jump from one view to another i do with two buttons next: [self.view addSubview:views[viewIndex]]; CATransition *animation = [CATransition animation]; [animation setDelegate:self]; [animation setDuration:1.0f]; [animation setType:@"rippleEffect"]; [animation setSubtype:kCATransitionFromTop]; //[animation setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]]; [self.view.layer addAnimation:animation forKey:@"transitionViewAnimation"]; Nothing seems to be bad, but the memory consumption grows with huge speed when i switch between views.. and then i get low memory warning or sometimes application will just crash. I have tried to use UIViewController array and was switching between the controllers: nothing changes, the memory low warning is what i end up with.. Maybe i need to clean the memory somehow? But how? ARC does not allow to use release and so on.. last what i have tried (sorry, maybe not very professional) before to add new subview is this NSArray *viewsToRemove = [self.view subviews]; for (UIView *views in viewsToRemove) { [views removeFromSuperview]; } But this does not help either.. Please don't judge too strong, i am still new to iOS and Objective-c..

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  • Doctrine: How to traverse from an entity to another 'linked' entity?

    - by ropstah
    I'm loading 3 different tables using a cross-join in Doctrine_RawSql. This brings me back the following object: User -> User class (doctrine base class) Settings -> DoctrineCollection of Setting User_Settings -> DoctrineCollection of User_Setting The object above is the result of a many-to-many relationship between User and Setting where User_Setting acts as a reference table. User_Setting also contains another field named value. This obviously contains the value of the corresponding Setting. All good so far, however the Settings and User_Settings properties of the returned User object are in no way linked to each other (apart from the setting_id field ofcourse). Is there any direct way to traverse directly from the Settings property to the corresponding User_Settings property? This is the corresponding query: $sets = new Doctrine_RawSql(); $sets->select('{us.*}, {s.*}, {uset.*}') ->from('(User us CROSS JOIN Setting s) LEFT JOIN User_Setting uset ON us.user_id = uset.user_id AND s.setting_id = uset.setting_id') ->addComponent('us', 'User us') ->addComponent('uset', 'us.User_Setting uset') ->addComponent('s', 'us.Setting s') ->where('s.category_id = ? AND us.usr_auto_key = ?',array(1, 1)); $sets = $sets->execute();

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  • Scientific Data processing(Graph comparison and interpretation)

    - by pinkynobrain
    Hi stackoverflow friends, I'm trying to write a program to automate one of my more boring and repetative work tasks. I have some programming experience but none with processing or interpreting large volumes of data so i am seeking your advice(both suggestions of techneques to try and also things to read to learn more about doing this stuff). I have a piece of equipment that monitors an experiment by taking repeated samples and displays the readings on its screen as a graph. The input of experiment can be altered and one of these changes should produce a change in a section of the graph which i currently identify by eye and is what im looking for in the experiment. I want to automate it so that a computer looks at a set of results and spots the experiment input that causes the change. I can already extract the results from the machine. Currently they results for a run are in the form of an integer array with the index being the sample number and the corresponding value being the measurement. The overall shape of the graph will be similar for each experiment run. The change im looking for will be roughly the same and will occur in approximatly the same place every time for the correct experiment input. Unfortunatly there are a few gotcha's that make this problem more difficult. There is some noise in the measuring process which mean there is some random variation in the measured values between different runs. Although the overall shape of the graph remains the same. The time the experiment takes varies slightly each run causing two effects. First, the a whole graph may be shifted slightly on the x axis relative to another runs graph. Second, individual features may appear slightly wider or narrower in different runs. In both these cases the variation isn't particularly large and you can assume that the only non random variation is caused by the correct input being found. Thank you for your time, Pinky

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  • C++ read registry string value in char*

    - by Sunny
    I'm reading a registry value like this: char mydata[2048]; DWORD dataLength = sizeof(mydata); DWORD dwType = REG_SZ; ..... open key, etc ReqQueryValueEx(hKey, keyName, 0, &dwType, (BYTE*)mydata, &dataLength); My problem is, that after this, mydata content looks like: [63, 00, 3A, 00, 5C, 00...], i.e. this looks like a unicode?!?!. I need to convert this somehow to be a normal char array, without these [00], as they fail a simple logging function I have. I.e. if I call like this: WriteMessage(mydata), it outputs only "c", which is the first char in the registry. I have calls to this logging function all over the place, so I'd better of not modify it, but somehow "fix" the registry value. Here is the log function: void Logger::WriteMessage(const char *msg) { time_t now = time(0); struct tm* tm = localtime(&now); std::ofstream logFile; logFile.open(filename, std::ios::out | std::ios::app); if ( logFile.is_open() ) { logFile << tm->tm_mon << '/' << tm->tm_mday << '/' << tm->tm_year << ' '; logFile << tm->tm_hour << ':' << tm->tm_min << ':' << tm->tm_sec << "> "; logFile << msg << "\n"; logFile.close(); } }

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  • Question on Split usage in Perl

    - by Nano HE
    Hello. I wrote an small script to use Split() as this, use strict; use warnings; use Data::Dumper; my $fh = \*DATA; while(my $line = <$fh>) { my @values = split(':', $line); foreach my $val (@values) { print "$val\n"; } } __DATA__ 1 : Hello World String10 : NO : A1B2,B3 11 : Hello World String11 : YES : A11B2,B3,B14,B25 A1B2,B3 and A11B2,B3 are characters form like Only One Letter A and One or Two Number 2, 3, 14,25 etc then concatenated with Only One Letter B and one or two Numbers like 2, 3, 14,25. etc Now out put as this 1 Hello World String10 NO A1B2,B3 11 Hello World String11 YES A11B2,B3,B14,B25 How can I hold the last array member from @values and made concatenation and out put as this. 1 Hello World String1 NO A1B2,A1B3 11 Hello World String11 YES A11B2,A11B3,A11B14,A11B25 Appreciated for your comments and replies. [update] My out put need the concatenation followed the rule. A and one or two numbers and joined by B and one or two numbers split by ,

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  • Issue with transparent texture on 3D primitive, XNA 4.0

    - by Bevin
    I need to draw a large set of cubes, all with (possibly) unique textures on each side. Some of the textures also have parts of transparency. The cubes that are behind ones with transparent textures should show through the transparent texture. However, it seems that the order in which I draw the cubes decides if the transparency works or not, which is something I want to avoid. Look here: cubeEffect.CurrentTechnique = cubeEffect.Techniques["Textured"]; Block[] cubes = new Block[4]; cubes[0] = new Block(BlockType.leaves, new Vector3(0, 0, 3)); cubes[1] = new Block(BlockType.dirt, new Vector3(0, 1, 3)); cubes[2] = new Block(BlockType.log, new Vector3(0, 0, 4)); cubes[3] = new Block(BlockType.gold, new Vector3(0, 1, 4)); foreach(Block b in cubes) { b.shape.RenderShape(GraphicsDevice, cubeEffect); } This is the code in the Draw method. It produces this result: As you can see, the textures behind the leaf cube are not visible on the other side. When i reverse index 3 and 0 on in the array, I get this: It is clear that the order of drawing is affecting the cubes. I suspect it may have to do with the blend mode, but I have no idea where to start with that.

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  • Why don't I need to bind my vertex buffer object before calling glDrawArrays?

    - by valmo
    I'm a bit confused why this still renders. I thought you need to bind a vertex buffer object so that glDrawArrays knows which vertex buffer to use. Here is my initialisation code.. // Create and bind vertex array to store vertex attribute states. glGenVertexArraysOES(NUM_VERTEX_ARRAYS, &m_vertexArray); glBindVertexArrayOES(m_vertexArray); // Create and bind vertex buffer to store vertex data. glGenBuffers(NUM_VERTEX_BUFFERS, &m_vertexBuffer); glBindBuffer(GL_ARRAY_BUFFER, m_vertexBuffer); glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * 36, &m_vertices[0], GL_STATIC_DRAW); glEnableVertexAttribArray(VertexAttribPosition); glVertexAttribPointer(VertexAttribPosition, 3, GL_FLOAT, GL_FALSE, 24, BUFFER_OFFSET(0)); glEnableVertexAttribArray(VertexAttribNormal); glVertexAttribPointer(VertexAttribNormal, 3, GL_FLOAT, GL_FALSE, 24, BUFFER_OFFSET(12)); glBindBuffer(GL_ARRAY_BUFFER, 0); glBindVertexArrayOES(0); Here is my render code. I'm confused why glDrawArrays still works when I bind 0 to GL_ARRAY_BUFFER. glBindVertexArrayOES(m_vertexArray); glBindBuffer(GL_ARRAY_BUFFER, 0); glDrawArrays(GL_TRIANGLES, 0, 36); glBindVertexArrayOES(0);

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  • Return a Const Char* by reading an @property NSString in separate class

    - by Andrew
    I'm probably being an idiot here, but I cannot for the life of me find the answer that I'm looking for. I have an array of CalEvents returned from a CalendarStore query, and for other reasons I am finding the first location of any upcoming event for today that is not an all-day or multi-day event. +(const char*) suggestFirstiCalLocation{ CalCalendarStore *store = [CalCalendarStore defaultCalendarStore]; NSPredicate *allEventsPredicate = [CalCalendarStore eventPredicateWithStartDate:[NSDate date] endDate:[[NSDate date] initWithTimeIntervalSinceNow:3600] calendars:[store calendars]]; NSArray *currentEventCalendarArray = [store eventsWithPredicate:allEventsPredicate]; for (int i = 0; i< [currentEventCalendarArray count]; i++){ if (![[currentEventCalendarArray objectAtIndex:i] isAllDay]){ //Now that other events are cleared, check for multi-day NSDate *startOnDate = [[currentEventCalendarArray objectAtIndex:i] startDate]; NSDate *endOnDate = [[currentEventCalendarArray objectAtIndex:i] endDate]; if ([endOnDate timeIntervalSinceDate:startOnDate ] < 86400.0){ NSString * iCalLocation = [[currentEventCalendarArray objectAtIndex:i] location]; return [iCalLocation UTF8String]; } } } return ""; } For other reasons, I am returning a const char with the value of the location that is found. However, I cannot seem to return "iCalLocation" at all. The compiler fails on the line where I am initializing the "iCalLocation" variable: "Cannot convert to pointer type" Being frank: I am new to Objective-C, and I am still trying to figure points, properties, and such out.

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  • Magento: How do I get observers to work in an external script?

    - by Laizer
    As far as I can tell, when a script is run outside of Magento, observers are not invoked when an event is fired. Why? How do I fix it? Below is the original issue that lead me to this question. The issue is that the observer that would apply the catalog rule is never called. The event fires, but the observer doesn't pick it up. I'm running an external script that loads up a Magento session. Within that script, I'm loading products and grabbing a bunch of properties. The one issue is that getFinalPrice() does not apply the catalog rules that apply to the product. I'm doing everything I know to set the session, even a bunch of stuff that I think is superfluous. Nothing seems to get these rules applied. Here's a test script: require_once "app/Mage.php"; umask(0); $app = Mage::app("default"); $app->getTranslator()->init('frontend'); //Probably not needed Mage::getSingleton('core/session', array('name'=>'frontend')); $session = Mage::getSingleton("customer/session"); $session->start(); //Probably not needed $session->loginById(122); $product = Mage::getModel('catalog/product')->load(1429); echo $product->getFinalPrice(); Any insight is appreciated.

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  • Why does the output look like this?

    - by cjk
    I have a c program below, I would like to send out a 32 bit message in a particular order Eg.0x00000001. #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <stdint.h> struct test { uint16_t a; uint16_t b; }; int main(int argc, char const *argv[]) { char buf[4]; struct test* ptr=(struct test*)buf; ptr->a=0x0000; ptr->b=0x0001; printf("%x %x\n",buf[0],buf[1]); //output is 0 0 printf("%x %x\n",buf[2],buf[3]); //output is 1 0 return 0; } Then I test it by print out the values in char array. I got output in the above comments. Shouldn't the output be 0 0 and 0 1? since but[3] is the last byte? Is there anything I missed? Thanks!

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  • Is it possible that two requests at the same time double this code? (prevent double database entry)

    - by loostro
    1) The controller code (Symfony2 framework): $em = $this->getDoctrine()->getEntityManager(); // get latest toplist $last = $em->getRepository('RadioToplistBundle:Toplist')->findOneBy( array('number' => 'DESC') ); // get current year and week of the year $week = date('W'); $year = date('Y'); // if: // [case 1]: $last is null, meaning there are no toplists in the database // [case 2]: $last->getYear() or $last->getWeek() do not match current // year and week number, meaning that there are toplists in the // database, but not for current week // then: // create new toplist entity (for current week of current year) // else: // do nothing (return) if($last && $last->getYear() == $year && $last->getWeek() == $week) return; else { $new = new Toplist(); $new->setYear($year); $new->setWeek($week); $em->persist($new); $em->flush(); } This code is executed with each request to view toplist results (frontend) or list of toplists (backend). Anytime someone wants to access the toplist we first check if we should create a new toplist entity (for new week). 2) The question is: Is it possible that: User A goes to mydomain.com/toplist at 00:00:01 on Monday - the code should generate new entity the server slows down and it takes him 3 seconds to execute the code so new toplist entity is saved to database at 00:00:04 on Monday User B goes to mydomain.com/toplist at 00:00:02 on Monday at 00:00:02 there the toplist is not yet saved in database, thus UserB's request triggers the code to create another toplist entity And so.. after a few seconds we have 2 toplist entities for current week. Is this possible? How should I prevent this?

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  • Unable to send multiple AJAX request in a loop?

    - by Harish Kurup
    I am sending multiple AJAX request through a loop, but some request are successfully send not all.. my code goes here... for(var i=0; i<dataArray.length; i++) { var request=getHttpRequest(); request.open('post','update.php',false); request.setRequestHeader("Content-Type","application/x-www-form-urlencoded"); request.send("data="+dataArray[i]); if(request.readyState == 4) { alert("updated the data="+dataArray[i]); } } function getHttpRequest() { var request=false; if(window.XMLHttpRequest) { request=new XMLHttpRequest(); } else if(window.ActiveXObject) { try { request=new ActiveXObject("Msxml2.XMLHTTP"); } catch(e) { try { request=new ActiveXObject("Microsoft.XMLHTTP"); } catch(e) { request=false; } } } return request; } here in the above code, some data are being posted, but some dont, it does not return the readyState = 4. i.e if i have array with dataArray['1','2','3','4']; it updates only 1,2,and 4 and skips 3, or other value in between... is there any solution..please help...

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  • WCF: collection proxy type on client

    - by Unholy
    I have the following type in wsdl (it is generated by third party tool): <xsd:complexType name="IntArray"> <xsd:sequence> <xsd:element maxOccurs="unbounded" minOccurs="0" name="Elements" type="xsd:int" /> </xsd:sequence> </xsd:complexType> Sometimes Visual Studio generates: public class IntArray : System.Collections.Generic.List<int> {} And sometimes it doesn't generate any proxy type for this wsdl and just uses int[]. Collection type in Web Service configuration is System.Array. What could be the reason for such upredictable behavior? Edited: I found the way how I can reproduce this behavior. For examle we have two types: <xsd:complexType name="IntArray"> <xsd:sequence> <xsd:element maxOccurs="unbounded" minOccurs="0" name="Elements" type="xsd:int" /> </xsd:sequence> </xsd:complexType> <xsd:complexType name="StringArray"> <xsd:sequence> <xsd:element maxOccurs="unbounded" minOccurs="0" name="Elements" type="xsd:string" /> </xsd:sequence> </xsd:complexType> VS generates: public class IntArray : System.Collections.Generic.List<int> {} public class StringArray : System.Collections.Generic.List<string> {} Now I change StringArray type: <xsd:complexType name="StringArray"> <xsd:sequence> <xsd:element maxOccurs="unbounded" minOccurs="0" name="Elements" type="xsd:string" /> <xsd:any minOccurs="0" maxOccurs="unbounded" namespace="##any" processContents="lax" /> </xsd:sequence> <xsd:anyAttribute namespace="##any" processContents="lax"/> </xsd:complexType> VS generates proxy type for StringArray only. But not for IntArray.

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  • In AS3/Flex, how can I get from flat data to hierarchical data?

    - by Dave S
    I have some data that gets pulled out of a database and mapped to an arraycollection. This data has a field called parentid, and I would like to map the data into a new arraycollection with hierarchical information to then feed to an advanced data grid. I think I'm basically trying to take the parent object, add a new property/field/variable of type ArrayCollection called children and then remove the child object from the original list and clone it into the children array? Any help would be greatly appreciated, and I apologize ahead of time for this code: private function PutChildrenWithParents(accountData : ArrayCollection) : ArrayCollection{ var pos_inner:int = 0; var pos_outer:int = 0; while(pos_outer < accountData.length){ if (accountData[pos_outer].ParentId != null){ pos_inner = 0; while(pos_inner < accountData.length){ if (accountData[pos_inner].Id == accountData[pos_outer].ParentId){ accountData.addItemAt( accountData[pos_inner] + {children:new ArrayCollection(accountData[pos_outer])}, pos_inner ); accountData.removeItemAt(pos_outer); accountData.removeItemAt(pos_inner+1); } pos_inner++; } } pos_outer++; } return accountData; }

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  • How do I close a file after catching an IOException in java?

    - by DimDom
    All, I am trying to ensure that a file I have open with BufferedReader is closed when I catch an IOException, but it appears as if my BufferedReader object is out of scope in the catch block. public static ArrayList readFiletoArrayList(String fileName, ArrayList fileArrayList) { fileArrayList.removeAll(fileArrayList); try { //open the file for reading BufferedReader fileIn = new BufferedReader(new FileReader(fileName)); // add line by line to array list, until end of file is reached // when buffered reader returns null (todo). while(true){ fileArrayList.add(fileIn.readLine()); } }catch(IOException e){ fileArrayList.removeAll(fileArrayList); fileIn.close(); return fileArrayList; //returned empty. Dealt with in calling code. } } Netbeans complains that it "cannot find symbol fileIn" in the catch block, but I want to ensure that in the case of an IOException that the Reader gets closed. How can I do that without the ugliness of a second try/catch construct around the first? Any tips or pointers as to best practise in this situation is appreciated,

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  • C++ Dynamic Allocation Mismatch: Is this problematic?

    - by acanaday
    I have been assigned to work on some legacy C++ code in MFC. One of the things I am finding all over the place are allocations like the following: struct Point { float x,y,z; }; ... void someFunc( void ) { int numPoints = ...; Point* pArray = (Point*)new BYTE[ numPoints * sizeof(Point) ]; ... //do some stuff with points ... delete [] pArray; } I realize that this code is atrociously wrong on so many levels (C-style cast, using new like malloc, confusing, etc). I also realize that if Point had defined a constructor it would not be called and weird things would happen at delete [] if a destructor had been defined. Question: I am in the process of fixing these occurrences wherever they appear as a matter of course. However, I have never seen anything like this before and it has got me wondering. Does this code have the potential to cause memory leaks/corruption as it stands currently (no constructor/destructor, but with pointer type mismatch) or is it safe as long as the array just contains structs/primitive types?

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  • jQuery UI Autocomplete and CodeIgniter

    - by Kere Puki
    I am trying to implement a simple autocomplete script using jQuery UI and CodeIgniter 2 but my model keeps telling me there is an undefined variable so I dont know if my setup is right. My view $(function() { $("#txtUserSuburb").autocomplete({ source: function(request, response){ $.ajax({ url: "autocomplete/suggestions", data: { term: $("#txtUserSuburb").val() }, dataType: "json", type: "POST", success: function(data){ response(data); } }); }, minLength: 2 }); }); My controller function suggestions(){ $this->load->model('autocomplete_model'); $term = $this->input->post('term', TRUE); $rows = $this->autocomplete_model->getAutocomplete($term); echo json_encode($rows); } My Model function getAutocomplete() { $this->db->like('postcode', $term, 'after'); $query = $this->db->get('tbl_postcode'); $keywords = array(); foreach($query->result() as $row){ array_push($keywords, $row->postcode); } return $keywords; } There arent any errors except it doesn't seem to be passing the $term variable to the model.

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  • Which is the correct design pattern for my PHP application?

    - by user1487141
    I've been struggling to find good way to implement my system which essentially matches the season and episode number of a show from a string, you can see the current working code here: https://github.com/huddy/tvfilename I'm currently rewriting this library and want a nicer way to implement how the the match happens, currently essentially the way it works is: There's a folder with classes in it (called handlers), every handler is a class that implements an interface to ensure a method called match(); exists, this match method uses the regex stored in a property of that handler class (of which there are many) to try and match a season and episode. The class loads all of these handlers by instantiating each one into a array stored in a property, when I want to try and match some strings the method iterates over these objects calling match(); and the first one that returns true is then returned in a result set with the season and episode it matched. I don't really like this way of doing it, it's kind of hacky to me, and I'm hoping a design pattern can help, my ultimate goal is to do this using best practices and I wondered which one I should use? The other problems that exist are: More than one handler could match a string, so they have to be in an order to prevent the more greedy ones matching first, not sure if this is solvable as some of the regex patterns have to be greedy, but possibly a score system, something that shows a percentage of how likely the match is correct, i'd have no idea how to actually implement this though. I'm not if instantiating all those handlers is a good way of doing it, speed is important, but using best practices and sticking to design patterns to create good, extensible and maintainable code is my ultimate priority. It's worth noting the handler classes sometimes do other things than just regex matching, they sometimes prep the string to be matched by removing common words etc. Cheers for any help Billy

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  • Computation overhead in C# - Using getters/setters vs. modifying arrays directly and casting speeds

    - by Jeffrey Kern
    I was going to write a long-winded post, but I'll boil it down here: I'm trying to emulate the graphical old-school style of the NES via XNA. However, my FPS is SLOW, trying to modify 65K pixels per frame. If I just loop through all 65K pixels and set them to some arbitrary color, I get 64FPS. The code I made to look-up what colors should be placed where, I get 1FPS. I think it is because of my object-orented code. Right now, I have things divided into about six classes, with getters/setters. I'm guessing that I'm at least calling 360K getters per frame, which I think is a lot of overhead. Each class contains either/and-or 1D or 2D arrays containing custom enumerations, int, Color, or Vector2D, bytes. What if I combined all of the classes into just one, and accessed the contents of each array directly? The code would look a mess, and ditch the concepts of object-oriented coding, but the speed might be much faster. I'm also not concerned about access violations, as any attempts to get/set the data in the arrays will done in blocks. E.g., all writing to arrays will take place before any data is accessed from them. As for casting, I stated that I'm using custom enumerations, int, Color, and Vector2D, bytes. Which data types are fastest to use and access in the .net Framework, XNA, XBox, C#? I think that constant casting might be a cause of slowdown here. Also, instead of using math to figure out which indexes data should be placed in, I've used precomputed lookup tables so I don't have to use constant multiplication, addition, subtraction, division per frame. :)

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  • Handling large (object) datasets with PHP

    - by Aron Rotteveel
    I am currently working on a project that extensively relies on the EAV model. Both entities as their attributes are individually represented by a model, sometimes extending other models (or at least, base models). This has worked quite well so far since most areas of the application only rely on filtered sets of entities, and not the entire dataset. Now, however, I need to parse the entire dataset (IE: all entities and all their attributes) in order to provide a sorting/filtering algorithm based on the attributes. The application currently consists of aproximately 2200 entities, each with aproximately 100 attributes. Every entity is represented by a single model (for example Client_Model_Entity) and has a protected property called $_attributes, which is an array of Attribute objects. Each entity object is about 500KB, which results in an incredible load on the server. With 2000 entities, this means a single task would take 1GB of RAM (and a lot of CPU time) in order to work, which is unacceptable. Are there any patterns or common approaches to iterating over such large datasets? Paging is not really an option, since everything has to be taken into account in order to provide the sorting algorithm.

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  • How to mimic polymorphism in classes with template methods (c++)?

    - by davide
    in the problem i am facing i need something which works more or less like a polymorphic class, but which would allow for virtual template methods. the point is, i would like to create an array of subproblems, each one being solved by a different technique implemented in a different class, but holding the same interface, then pass a set of parameters (which are functions/functors - this is where templates jump up) to all the subproblems and get back a solution. if the parameters would be, e.g., ints, this would be something like: struct subproblem { ... virtual void solve (double& solution, double parameter)=0; } struct subproblem0: public subproblem { ... virtual void solve (double& solution, double parameter){...}; } struct subproblem1: public subproblem { ... virtual void solve (double* solution, double parameter){...}; } int main{ subproblem problem[2]; subproblem[0] = new subproblem0(); subproblem[1] = new subproblem1(); double argument0(0), argument1(1), sol0[2], sol1[2]; for(unsigned int i(0);i<2;++i) { problem[i]->solve( &(sol0[i]) , argument0); problem[i]->solve( &(sol1[i]) , argument1); } return 0; } but the problem is, i need the arguments to be something like Arg<T1,T2> argument0(f1,f2) and thus the solve method to be something of the likes of template<T1,T2> solve (double* solution, Arg<T1,T2> parameter) which cant obviously be declared virtual ( so cant be called from a pointer to the base class)... now i'm pretty stuck and don't know how to procede...

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  • content_tag_for a collection in Rails?

    - by Nick
    I have a Post model. Posts have many Comments. I want to generate a <ul> element for post.comments using content_tag_for. Ideally, it'd produce <ul id="comments_post_7" class="comments"> ... </ul> where 7 is the ID of the Post. The closest I can get uses <% content-tag-for :ul post, :comments do %> which produces <ul id="comments_post_7" class="post"> ... </ul> which is pretty close, except for the class="post". Using :class => :comments in the content_tag_for yields class="post comments", but I just want class="comments". It seems logical that I'd be able to use something like <% content_tag_for :ul post.comments do %> but, sadly, that yields <ul id="array_2181653100" class="array"> ... </ul> I've searched far and wide. I feel like I'm missing some elegant way to do this. Am I? Because, seriously, <ul id="comments_post_<%= post.id %>" class="comments"> is painful.

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  • In parallel.for share value more then one.

    - by user347918
    Here is problem. long sum = 0; Parallel.For(1, 10000, y => { sum1 += y;} ); Solution is .. Parallel.For<int>(0, result.Count, () => 0, (i, loop, subtotal) => { subtotal += result[i]; return subtotal; }, (x) => Interlocked.Add(ref sum, x) ); if there are two parameters in this code. For example long sum1 = 0; long sum2 = 0; Parallel.For(1, 10000, y => { sum1 += y; sum2=sum1*y; } ); what will we do ? i am guessing that have to use array ! int[] s=new int[2]; Parallel.For<int[]>(0, result.Count, () => s, (i, loop, subtotal) => { subtotal[0] += result[i]; subtotal[1] -= result[i]; return subtotal; }, (x) => Interlocked.Add(ref sum1, x[0]) //but how about sum1 i tried several way but it doesn't work. //for example like that //(x[0])=> Interlocked.Add (ref sum1, x[0]) //(x[1])=> Interlocked.Add (ref sum2, x[1]));

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  • KSH: Variables containing double quotes

    - by nitrobass24
    I have a string called STRING1 that could contain double quotes. I am echoing the string through sed to pull out puntuation then sending to array to count certain words. The problem is I cannot echo variables through double quotes to sed. I am crawling our filesystems looking for files that use FTP commands. I grep each file for "FTP" STRING1=`grep -i ftp $filename` If you echo $STRING1 this is the output (just one example) myserver> echo "Your file `basename $1` is too large to e-mail. You must ftp the file to BMC tech support. \c" echo "Then, ftp it to ftp.bmc.com with the user name 'anonymous.' \c" echo "When the ftp is successful, notify technical support by phone (800-537-1813) or by e-mail ([email protected].)" Then I have this code STRING2=`echo $STRING1|sed 's/[^a-zA-Z0-9]/ /g'` I have tried double quoting $STRING1 like STRING2=`echo "$STRING1"|sed 's/[^a-zA-Z0-9]/ /g'` But that does not work. Single Qoutes, just sends $STRING1 as the string to sed...so that did not work. What else can I do here?

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  • Should try...catch go inside or outside a loop?

    - by mmyers
    I have a loop that looks something like this: for(int i = 0; i < max; i++) { String myString = ...; float myNum = Float.parseFloat(myString); myFloats[i] = myNum; } This is the main content of a method whose sole purpose is to return the array of floats. I want this method to return null if there is an error, so I put the loop inside a try...catch block, like this: try { for(int i = 0; i < max; i++) { String myString = ...; float myNum = Float.parseFloat(myString); myFloats[i] = myNum; } } catch (NumberFormatException ex) { return null; } But then I also thought of putting the try...catch block inside the loop, like this: for(int i = 0; i < max; i++) { String myString = ...; try { float myNum = Float.parseFloat(myString); } catch (NumberFormatException ex) { return null; } myFloats[i] = myNum; } So my question is: is there any reason, performance or otherwise, to prefer one over the other? EDIT: The consensus seems to be that it is cleaner to put the loop inside the try/catch, possibly inside its own method. However, there is still debate on which is faster. Can someone test this and come back with a unified answer? (EDIT: did it myself, but voted up Jeffrey and Ray's answers)

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