Search Results

Search found 69357 results on 2775 pages for 'data oriented design'.

Page 90/2775 | < Previous Page | 86 87 88 89 90 91 92 93 94 95 96 97  | Next Page >

  • C++ design question, container of instances and pointers

    - by Tom
    Hi all, Im wondering something. I have class Polygon, which composes a vector of Line (another class here) class Polygon { std::vector<Line> lines; public: const_iterator begin() const; const_iterator end() const; } On the other hand, I have a function, that calculates a vector of pointers to lines, and based on those lines, should return a pointer to a Polygon. Polygon* foo(Polygon& p){ std::vector<Line> lines = bar (p.begin(),p.end()); return new Polygon(lines); } Here's the question: I can always add a Polygon (vector Is there a better way that dereferencing each element of the vector and assigning it to the existing vector container? //for line in vector<Line*> v //vcopy is an instance of vector<Line> vcopy.push_back(*(v.at(i)) I think not, but I dont really like that approach. Hopefully, I will be able to convince the author of the class to change it, but I cant base my coding right now to that fact (and i'm scared of a performance hit). Thanks in advance.

    Read the article

  • C++ design question, container of instances and pointers

    - by Tom
    Hi all, Im wondering something. I have class Polygon, which composes a vector of Line (another class here) class Polygon { std::vector<Line> lines; public: const_iterator begin() const; const_iterator end() const; } On the other hand, I have a function, that calculates a vector of pointers to lines, and based on those lines, should return a pointer to a Polygon. Polygon* foo(Polygon& p){ std::vector<Line> lines = bar (p.begin(),p.end()); return new Polygon(lines); } Here's the question: I can always add a Polygon (vector Is there a better way that dereferencing each element of the vector and assigning it to the existing vector container? //for line in vector<Line*> v //vcopy is an instance of vector<Line> vcopy.push_back(*(v.at(i)) I think not, but I dont really like that approach. Hopefully, I will be able to convince the author of the class to change it, but I cant base my coding right now to that fact (and i'm scared of a performance hit). Thanks in advance.

    Read the article

  • Facebook Privacy Permissions Design

    - by Ian
    Does anyone know the general layout of how facebook's privacy permissions system works (database)? I've been trying to figure out how they manage to have such a complex set of rules be applied to various content on their site, yet it remains fast. How are they doing that?

    Read the article

  • basic database design table on rails

    - by runcode
    I am confuse on a concept. I am doing this on rails. Is that Entity set equal to a table in the database? Is that Relationship set equal to a table in the database? Let say we have Entity set "USER" and Entity set "POST" and Entity set "COMMENT" User- can post many posts and comments as they want Post- belong to users Comments-belong to posts ,users, so comment is weak entity. SCHEMA ====== USER -id -name POST -id -user_id(FK) -comment_id (FK) COMMENT -id -user_id (FK) -post_id (FK) so USER,POST,COMMENT are tables I think. And what else is a table? And do I need a table for the relationship??

    Read the article

  • Best Design Pattern to Implement while Mapping Actions in MVC

    - by FidEliO
    What could be the best practices of writing the following case: We have a controller which based on what paths users take, take different actions. For example: if user chooses the path /path1/hello it will say hello. If a user chooses /path1/bye?name="Philipp" it will invoke sayGoodBye() and etc. I have written a switch statement inside the controller which is simple, however IMO not efficient. What are the best way to implement this, considering that paths are generally String. private void takeAction() { switch (path[1]) { case "hello": //sayHello(); break; case "bye": //sayBye(); break; case "case3": //Blah(); break; ... } }

    Read the article

  • Needs opinions based on design guidelines .

    - by Abu Hamzah
    i am in the process of desigining my domain model and i know its very hard to suggest without knowledge of domain but what i am asking is how to implement or the best way of implementing the baseclass in my domain model. here are few classes: PartialPerson.cs Facilities.cs Visit.cs EntryPoint.cs etc.... my baseclass looks like this: public abstract class BaseClass { public int InfoId { get; } public int PersonId { get; } } here is what i am confused and need help. how do i implement the above baseclass? in the PartialPerson,Facilities,Visit...

    Read the article

  • Design pattern: Polymorphism for list of objects

    - by ziang
    Suppose I have a class A, and A1, A2 inherits from A. There are 2 functions: List<A1> getListA1(){...} List<A2> getListA2(){...} Now I want to do something similar to both A1 and A2 in another function public void process(List<A>){...} If I want to pass the instance of either ListA1 or ListA2, of course the types doesn't match because the compiler doesn't allow the coercion from List< A1 to List< A. I can't do something like this: List<A1> listA1 = getListA1(); List<A> newList = (List<A>)listA1; //this is not allowed. So what is the best approach to the process()? Is there any way to do it in a universal way rather than write the similar code to both List and List?

    Read the article

  • Design best practice - best way to handle user selection

    - by user1457227
    I'm an experienced developer (WPF) moving over to Android development. My question: an app I am developing allows the user to browse their local storage (such as SDCARD) and select a file. Now, should I simply create a new Activity (after the user has made a selection) to handle what I want to have the app do with that chosen file, -or- is the better approach to pass the path/name of the selected file back to the main Activity and let IT launch the next Activity? In other words, is the better practice to have the main Activity launch other (support) activities, or is it perfectly ok and normal to have one activity chain to another and on and on? Thanks!

    Read the article

  • Design pattern suggestion

    - by Avinash
    Following is the problem statement. There are n numbers of match strings, If event A occurs and then in certain period of time event B occurs then I do not raise alarm. but if B do not occurs then i have to raise alarm. There can be multiple chain of events which defines whether to raise alarm or not.

    Read the article

  • Database design -- does it respect 3rd NF?

    - by Flavius
    Hi I have the following relations (tables) in a relational model Person person_id, first_name, last_name, address Student person_id, matr_nr Teacher person_id, salary Lecture lecture_id, lect_name, lect_description Attendees lecture_id, person_id, date I'm wondering about the functional dependencies of Student and Teacher. Do these tables respect the 3rd normal form? Which should be the primary keys of these tables?

    Read the article

  • Which design pattern fits - strategy makes sense ?

    - by user554833
    --Bump *One desperate try to get someone's attention I have a simple database table that stores list of users who have subscribed to folders either by email OR to show up on the site (only on the web UI). In the storage table this is controlled by a number(1 - show on site 2- by email). When I am showing in UI I need to show a checkbox next to each of folders for which the user has subscribed (both email & on site). There is a separate table which stores a set of default subscriptions which would apply to each user if user has not expressed his subscription. This is basically a folder ID and a virtual group name. But, Email subscriptions do not count for applying these default groups. So if no "on site" subscription apply default group. Thats the rule. How about a strategy pattern here (Pseudo code) Interface ISubscription public ArrayList GetSubscriptionData(Pass query object) Public class SubscriptionWithDefaultGroup Implement ArrayList GetSubscriptionData(Pass query object) Public class SubscriptionWithoutDefaultGroup Implement ArrayList GetSubscriptionData(Pass query object) Public class SubscriptionOnlyDefaultGroup Implement ArrayList GetSubscriptionData(Pass query object) does this even make sense? I would be more than glad for receive any criticism / help / notes. I am learning. Cheers

    Read the article

  • Decorator Design Pattern Use With Service Objects (wSingleton)

    - by Dustin
    I'm working on a project where I need to add some functionality to a service object and using a decorator to add it in seems like a good fit. However, I've only ever used decorators with simple beans, never on a singleton like a service object. Has anyone ever done this before and what are the pros and cons? In this case I don't think creating a subclass will work so a decorator seems to be a good fit. What are your thoughts on doing this?

    Read the article

  • Policies Array Class-Design wrapper

    - by PT
    Hi, i want to write an wrapper for different Array Classes with different Policies. For example: typedef ArrayType<useValArray,StdAllocator> Array; // one global assignment I want to use the class like a blitz++ Array for example: Array<double,2> x(2,2); //maps the Array to an Valarray or to a Blitz++ Array Array<double,2> x2(5,6); is this Posible? Which technics i need to realise that?

    Read the article

  • sports league database design

    - by John
    Hello, I'm developing a database to store statistics for a sports league. I'd like to show several tables: - league table that indicates the position of the team in the current and previous fixture - table that shows the position of a team in every fixture in the championship I have a matches table: Matches (IdMatch, IdTeam1, IdTeam2, GoalsTeam1, GoalsTeam2) Whith this table I can calculate the total points of every team based on the matches the team played. But every time I want to show the league table I have to calculate the points. Also I have a problem to calculate in which position classified a team in the last 10 fixtures cause I have to make 10 queries. To store the league table for every fixture in a database table is another approach, but every time I change a match already played I have to recalculate every fixture from there... Is there a better approach for this problem? Thanks

    Read the article

  • Help Desk Database Design

    - by user237244
    The company I work at has very specific and unique needs for a help desk system, so none of the open source systems will work for us. That being the case, I created a custom system using PHP and MySQL. It's far from perfect, but it's infinitely better than the last system they were using; trust me! It meets most of our needs quite nicely, but I have a question about the way I have the database set up. Here are the main tables: ClosedTickets ClosedTicketSolutions Locations OpenTickets OpenTicketSolutions Statuses Technicians When a user submits a help request, it goes in the "OpenTickets" table. As the technicians work on the problem, they submit entries with a description of what they've done. These entries go in the "OpenTicketSolutions" table. When the problem has been resolved, the last technician to work on the problem closes the ticket and it gets moved to the "ClosedTickets" table. All of the solution entries get moved to the "ClosedTicketSolutions" table as well. The other tables (Locations, Statuses, and Technicians) exist as a means of normalization (each location, status, and technician has an ID which is referenced). The problem I'm having now is this: When I want to view a list of all the open tickets, the SQL statement is somewhat complicated because I have to left join the "Locations", "Statuses", and "Technicians" tables. Fields from various tables need to be searchable as well. Check out how complicated the SQL statement is to search closed tickets for tickets submitted by anybody with a first name containing "John": SELECT ClosedTickets.*, date_format(ClosedTickets.EntryDate, '%c/%e/%y %l:%i %p') AS Formatted_Date, date_format(ClosedDate, '%c/%e/%y %l:%i %p') AS Formatted_ClosedDate, Concat(Technicians.LastName, ', ', Technicians.FirstName) AS TechFullName, Locations.LocationName, date_format(ClosedTicketSolutions.EntryDate, '%c/%e/%y') AS Formatted_Solution_EntryDate, ClosedTicketSolutions.HoursSpent AS SolutionHoursSpent, ClosedTicketSolutions.Tech_ID AS SolutionTech_ID, ClosedTicketSolutions.EntryText FROM ClosedTickets LEFT JOIN Technicians ON ClosedTickets.Tech_ID = Technicians.Tech_ID LEFT JOIN Locations ON ClosedTickets.Location_ID = Locations.Location_ID LEFT JOIN ClosedTicketSolutions ON ClosedTickets.TicketNum = ClosedTicketSolutions.TicketNum WHERE (ClosedTickets.FirstName LIKE '%John%') ORDER BY ClosedDate Desc, ClosedTicketSolutions.EntryDate, ClosedTicketSolutions.Entry_ID One thing that I'm not able to do right now is search both open and closed tickets at the same time. I don't think a union would work in my case. So I'm wondering if I should store the open and closed tickets in the same table and just have a field indicating whether or not the ticket is closed. The only problem I can forsee is that we have so many closed tickets already (nearly 30,000) so the whole system might perform slowly. Would it be a bad idea to combine the open and closed tickets?

    Read the article

  • What Design Pattern To Replace 'CurrentStep' Variable

    - by Rob P.
    Tried to search but didn't know how to phrase it. I've got some code that is essentially... Private CurMajorStep as Integer = 0 Private CurMinorStep as Integer = 0 Public Sub PerformNextStep() Select Case iMajorStep Case 0 ThingOne() Case 1 ThingTwo() Case 2 ThingThree() Case 3 ThingFour() Case 4 AnythingElse() Case 5 Finish() End Select End Sub And then, in some of those, the CurMinorStep keeps track of the current state of that particular 'step'. I hope that all makes sense. The code is messy and I know it's going to be problematic to maintain. Can someone point me to a clean OO pattern to handle this?

    Read the article

  • C++: How to design a utility class?

    - by Martijn Courteaux
    Hi, The title says it all. But I don't know if I should go for static methods, just a header, a class, or something else? What would be best practice? But, I don't want to have an instance of a utility class. I want to add functions like: Uint32 MapRGB (int r, int g, int b); const char* CopyString(const char* char); // etc. You know: utility methods...

    Read the article

  • Database Design Question

    - by Soo
    Ok SO, I have a user table and want to define groups of users together. The best solution I have for this is to create three database tables as follows: UserTable user_id user_name UserGroupLink group_id member_id GroupInfo group_id group_name This method keeps the member and group information separate. This is just my way of thinking. Is there a better way to do this? Also, what is a good naming convention for tables that link two other tables?

    Read the article

  • Webmin / Virtualmin running php as www-data, is locked out of viewing .htaccess and writing

    - by Kirill
    I've asked this on the virtualmin forums, but haven't had any help from there. Recently, "something" happened and it seems that the apache service has gone a bit weird. What it does: it runs all apache traffic as www-data and sometimes spawns the php5-cgi process as www-data, this is a problem because all the domain users own their directories and default permissions don't let www-data write to these folders (file uploads are dead) or read .htaccess (permalinks are broken in wordpress). I've googled this for about a week straight now, tried pretty much everything I could find and achieved nothing. The only thing that I think might actually be the cause of all this is this page: http:// - i.imgur.com/NYW3x.png (got shut down by the spam filter) So I figured if I set it to "default", this might magically start working again, but all it does is "crash" apache (all websites timeout). I figure it's something to do with the "mpm" module or something, but I can't find anything relevant in the settings to modify for it to work. Can someone please point me in the right direction? System info: Webmin version 1.580 Kernel and CPU Linux 2.6.35.4-rscloud on x86_64 Virtualmin version 3.90.gpl GPL Ubuntu 10.04 LTS (Lucid) A couple screenshots of top http://i.imgur.com/U2DTK.png http://i.imgur.com/sNPKs.png

    Read the article

  • Hard drive failed, suspected filesystem corruption, still cannot salvage any data from harddrive

    - by Hippy-Head
    Firstly, I am terribly sorry if this is a duplicate, but I couldn't find a similar issue to mine, so here goes. I have a 1TB hdd bought around 8 months ago used as backup hard drive. I have not used the drive for a period of time whatsoever, and when I was trying to get back to some files on it, it was completely wiped just like that. At first it would not boot I tried everything from command line chkdsk and filesystem recovery software to rebuilt it. After a few attempts I managed to initialize it, at that time it was an achievement. The problems started when I tried to recover the data inside, I have used A LOT of software free and commercial software on both Mac and Windows, with the help of cmd or Terminal commands, however no data of any kind was recovered, even after leaving it thoroughly scan for around 9-10 hours all night sometimes longer, with no results at all. I am somewhat desperate, I am usually good at retrieving data from corrupt hard drives, but this is not the case. Call me paranoid, but I do not want to give it to someone to fix it for me, as I have a lot of photos and personal stuff that I do not want anyone to see.

    Read the article

  • Recover NTFS data from a ZFS pool that was exposed as an iSCSI target

    - by David
    This was me being stupid and the data is by no means critical and is now a learning experience first, time saver second. I set up a 100GB iSCSI target via the bare bone instructions in napp-it. It's a volume LU. I then had my Windows 7 machine connect to the iSCSI target, formatted it to NTFS, and tested the performance of it with some large iso file transfers. I then unmapped the drive, reconnected to the target, and was forced to format to NTFS again. It was then I realized the files I had transferred only existed on the iSCSI target. I threw a little fit and then went about my business. When I was cleaning up my experiment I noticed in this screen: http://imgur.com/1xlcu.jpg That is my experimental target tank/iSCSI and it still has a lot of data in it. Assuming my isos are still in this pool how would I go about recovering them? While writing this I used GetDataBackup for NTFS from www.runtime.org. And while it found two previous NTFS partitions there was no data.

    Read the article

  • Cross OS data recover question, USB drive involved.

    - by Moshe
    Here's the story: A MacBook had OS X 10.4 and Windows XP dual booting using rEFIt. Then the Windows partition gets corrupted and it won't boot. Presumably a virus. There were sensitive files there and those were successfully copied to a USB drive and then 10.5 was installed on the hard drive, formatting the drive in the process. The USB drive's contacts cracked and he data is lost from there, unless it can be resoldered. The issues is that there is too much solder there already. So, how can the data in question be recovered? The files were Microsoft Money (not the latest version) files for the Windows version of the program. Right now, only OS X is installed on the MacBook. Is there Mac based program that can recover the Windows data or am I better off trying to resolder the drive? Does anyone know how to best resolder a USB drive more than once, where the first solder is ther, but detached from the silicon? Also, what format (extension) are Microsoft Money files? In need of help!

    Read the article

< Previous Page | 86 87 88 89 90 91 92 93 94 95 96 97  | Next Page >