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  • C++ Reference Book

    - by m00st
    Can someone list a C++ book that is just a reference to the standard library? I don't need a "learning c++" book just one that is a reference. Or at least official documentation or something? Googling only reveals "fan-site" reference.

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  • What browser incompatibilities does jquery solve?

    - by pd1138
    I'm currently on the fence about using or not using jquery. I've spent hours researching the pros and cons of using jquery (or any library for that matter). One of the big selling points of jquery is that it frees a developer from worrying about browser incompatibilities. I've tried to find any documentation on exactly which incompatibilities it overcomes. So far I haven't found any. Can anyone help me out with this.

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  • Generic DRM (Distributed resource management) wrapper

    - by Pavel Bernshtam
    I need to write a software, which launches DRM jobs in a customer environment and monitors those jobs status. It should work with various customer environments and DRMs - like LSF, Sun Grid and others. Can you recommend some 3rd party library, which hides DRM differences from me and has API like "launch job", "get list of jobs", "get job status" etc. ? Both Java and native libraries are good for me.

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  • I can write code...but can't design well. Any suggestions?

    - by user396089
    I feel that I am good at writing code in bits and pieces, but my designs really suck. The question is how do I improve my designs (in order to become a better designer). I think schools and colleges do a good job of teaching people as to how to become good at mathematical problem solving, but lets admit the fact that most programs taught at school are generally around 1000 - 2000 lines long, which means that it is mostly an academic exercise and no way reflects the complexity of real world software (a few hundred thousand to millions of lines of code). This is where I believe that even projects like topcoder/project euler also won't be of much help, they might sharpen your mathematical problem solving ability - but you might become a theoretician programmer; someone who is more interested in the nice, clean stuff, and someone who is utterly un-interested in the day to day mundane and hairy stuff that most application programmers deal with. So my question is how do I improve my design skills? That is the ability to design small/medium scale applications that will go into a few thousand of lines of code? How can I learn design skills that would help me build a better html editor kit, or some graphics program like gimp?

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  • how to create multiple pages in Xcode iphone apps

    - by al7r
    Hi there, i am starting my experience with iphone sdk. and i have a question, which is i am trying to create two pages to the app but i don't know how to link them or design them. like when i start the Xcode i find one page named View to design in it, i want to make that page a welcoming page then the user choose one of the three choices he see in that page. Once he clicked on one of them the program take him to the next page or the page he chose. thank you

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  • Proper Way to Create Standards-Compliant Webpage Structure

    - by Sakamoto Kazuma
    I have been working through projects involving packages that do all the web design stuff for me for the past few years. I will admit that I have not been able to focus any on actual web design. I was wondering what the standard is these days for website layouts. Are layout-tables looked down upon now? Or are all layouts done with div tags and controlled through CSS? Are frames even used anymore? Note I am not talking about chart-table tables when I say layout tables.

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  • Silverlight 4 + WCF RIA - Data Service Design Best Practices

    - by Chadd Nervig
    Hey all. I realize this is a rather long question, but I'd really appreciate any help from anyone experienced with RIA services. Thanks! I'm working on a Silverlight 4 app that views data from the server. I'm relatively inexperienced with RIA Services, so have been working through the tasks of getting the data I need down to the client, but every new piece I add to the puzzle seems to be more and more problematic. I feel like I'm missing some basic concepts here, and it seems like I'm just 'hacking' pieces on, in time-consuming ways, each one breaking the previous ones as I try to add them. I'd love to get the feedback of developers experienced with RIA services, to figure out the intended way to do what I'm trying to do. Let me lay out what I'm trying to do: First, the data. The source of this data is a variety of sources, primarily created by a shared library which reads data from our database, and exposes it as POCOs (Plain Old CLR Objects). I'm creating my own POCOs to represent the different types of data I need to pass between server and client. DataA - This app is for viewing a certain type of data, lets call DataA, in near-realtime. Every 3 minutes, the client should pull data down from the server, of all the new DataA since the last time it requested data. DataB - Users can view the DataA objects in the app, and may select one of them from the list, which displays additional details about that DataA. I'm bringing these extra details down from the server as DataB. DataC - One of the things that DataB contains is a history of a couple important values over time. I'm calling each data point of this history a DataC object, and each DataB object contains many DataCs. The Data Model - On the server side, I have a single DomainService: [EnableClientAccess] public class MyDomainService : DomainService { public IEnumerable<DataA> GetDataA(DateTime? startDate) { /*Pieces together the DataAs that have been created since startDate, and returns them*/ } public DataB GetDataB(int dataAID) { /*Looks up the extended info for that dataAID, constructs a new DataB with that DataA's data, plus the extended info (with multiple DataCs in a List<DataC> property on the DataB), and returns it*/ } //Not exactly sure why these are here, but I think it //wouldn't compile without them for some reason? The data //is entirely read-only, so I don't need to update. public void UpdateDataA(DataA dataA) { throw new NotSupportedException(); } public void UpdateDataB(DataB dataB) { throw new NotSupportedException(); } } The classes for DataA/B/C look like this: [KnownType(typeof(DataB))] public partial class DataA { [Key] [DataMember] public int DataAID { get; set; } [DataMember] public decimal MyDecimalA { get; set; } [DataMember] public string MyStringA { get; set; } [DataMember] public DataTime MyDateTimeA { get; set; } } public partial class DataB : DataA { [Key] [DataMember] public int DataAID { get; set; } [DataMember] public decimal MyDecimalB { get; set; } [DataMember] public string MyStringB { get; set; } [Include] //I don't know which of these, if any, I need? [Composition] [Association("DataAToC","DataAID","DataAID")] public List<DataC> DataCs { get; set; } } public partial class DataC { [Key] [DataMember] public int DataAID { get; set; } [Key] [DataMember] public DateTime Timestamp { get; set; } [DataMember] public decimal MyHistoricDecimal { get; set; } } I guess a big question I have here is... Should I be using Entities instead of POCOs? Are my classes constructed correctly to be able to pass the data down correctly? Should I be using Invoke methods instead of Query (Get) methods on the DomainService? On the client side, I'm having a number of issues. Surprisingly, one of my biggest ones has been threading. I didn't expect there to be so many threading issues with MyDomainContext. What I've learned is that you only seem to be able to create MyDomainContextObjects on the UI thread, all of the queries you can make are done asynchronously only, and that if you try to fake doing it synchronously by blocking the calling thread until the LoadOperation finishes, you have to do so on a background thread, since it uses the UI thread to make the query. So here's what I've got so far. The app should display a stream of the DataA objects, spreading each 3min chunk of them over the next 3min (so they end up displayed 3min after the occurred, looking like a continuous stream, but only have to be downloaded in 3min bursts). To do this, the main form initializes, creates a private MyDomainContext, and starts up a background worker, which continuously loops in a while(true). On each loop, it checks if it has any DataAs left over to display. If so, it displays that Data, and Thread.Sleep()s until the next DataA is scheduled to be displayed. If it's out of data, it queries for more, using the following methods: public DataA[] GetDataAs(DateTime? startDate) { _loadOperationGetDataACompletion = new AutoResetEvent(false); LoadOperation<DataA> loadOperationGetDataA = null; loadOperationGetDataA = _context.Load(_context.GetDataAQuery(startDate), System.ServiceModel.DomainServices.Client.LoadBehavior.RefreshCurrent, false); loadOperationGetDataA.Completed += new EventHandler(loadOperationGetDataA_Completed); _loadOperationGetDataACompletion.WaitOne(); List<DataA> dataAs = new List<DataA>(); foreach (var dataA in loadOperationGetDataA.Entities) dataAs.Add(dataA); return dataAs.ToArray(); } private static AutoResetEvent _loadOperationGetDataACompletion; private static void loadOperationGetDataA_Completed(object sender, EventArgs e) { _loadOperationGetDataACompletion.Set(); } Seems kind of clunky trying to force it into being synchronous, but since this already is on a background thread, I think this is OK? So far, everything actually works, as much of a hack as it seems like it may be. It's important to note that if I try to run that code on the UI thread, it locks, because it waits on the WaitOne() forever, locking the thread, so it can't make the Load request to the server. So once the data is displayed, users can click on one as it goes by to fill a details pane with the full DataB data about that object. To do that, I have the the details pane user control subscribing to a selection event I have setup, which gets fired when the selection changes (on the UI thread). I use a similar technique there, to get the DataB object: void SelectionService_SelectedDataAChanged(object sender, EventArgs e) { DataA dataA = /*Get the selected DataA*/; MyDomainContext context = new MyDomainContext(); var loadOperationGetDataB = context.Load(context.GetDataBQuery(dataA.DataAID), System.ServiceModel.DomainServices.Client.LoadBehavior.RefreshCurrent, false); loadOperationGetDataB.Completed += new EventHandler(loadOperationGetDataB_Completed); } private void loadOperationGetDataB_Completed(object sender, EventArgs e) { this.DataContext = ((LoadOperation<DataB>)sender).Entities.SingleOrDefault(); } Again, it seems kinda hacky, but it works... except on the DataB that it loads, the DataCs list is empty. I've tried all kinds of things there, and I don't see what I'm doing wrong to allow the DataCs to come down with the DataB. I'm about ready to make a 3rd query for the DataCs, but that's screaming even more hackiness to me. It really feels like I'm fighting against the grain here, like I'm doing this in an entirely unintended way. If anyone could offer any assistance, and point out what I'm doing wrong here, I'd very much appreciate it! Thanks!

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  • Product table, many kinds of product, each product has many parameters

    - by StoneHeart
    Hi, i'm have not much experience in table design. My goal is a product table(s), it must design to fix some requirement below: Support many kind of products (TV, Phone, PC, ...). Each kind of product has different set of parameters like: Phone will have Color, Size, Weight, OS... PC will have CPU, HDD, RAM... Set of parameters must be dynamic. You can add or edit any parameter you like. I don't want make a table for each kind of product. So I need help to find a correct solution. Thanks.

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  • Singleton: How should it be used

    - by Loki Astari
    Edit: From another question I provided an answer that has links to a lot of questions/answers about singeltons: More info about singletons here: So I have read the thread Singletons: good design or a crutch? And the argument still rages. I see Singletons as a Design Pattern (good and bad). The problem with Singleton is not the Pattern but rather the users (sorry everybody). Everybody and their father thinks they can implement one correctly (and from the many interviews I have done, most people can't). Also because everybody thinks they can implement a correct Singleton they abuse the Pattern and use it in situations that are not appropriate (replacing global variables with Singletons!). So the main questions that need to be answered are: When should you use a Singleton How do you implement a Singleton correctly My hope for this article is that we can collect together in a single place (rather than having to google and search multiple sites) an authoritative source of when (and then how) to use a Singleton correctly. Also appropriate would be a list of Anti-Usages and common bad implementations explaining why they fail to work and for good implementations their weaknesses. So get the ball rolling: I will hold my hand up and say this is what I use but probably has problems. I like "Scott Myers" handling of the subject in his books "Effective C++" Good Situations to use Singletons (not many): Logging frameworks Thread recycling pools /* * C++ Singleton * Limitation: Single Threaded Design * See: http://www.aristeia.com/Papers/DDJ_Jul_Aug_2004_revised.pdf * For problems associated with locking in multi threaded applications * * Limitation: * If you use this Singleton (A) within a destructor of another Singleton (B) * This Singleton (A) must be fully constructed before the constructor of (B) * is called. */ class MySingleton { private: // Private Constructor MySingleton(); // Stop the compiler generating methods of copy the object MySingleton(MySingleton const& copy); // Not Implemented MySingleton& operator=(MySingleton const& copy); // Not Implemented public: static MySingleton& getInstance() { // The only instance // Guaranteed to be lazy initialized // Guaranteed that it will be destroyed correctly static MySingleton instance; return instance; } }; OK. Lets get some criticism and other implementations together. :-)

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  • Where can I find free WPF controls and control templates?

    - by Geoffrey Chetwood
    Duplicate: Where can I find free WPF controls and control templates? I am looking for some recommendations on good places to find libraries of controls/templates/styles for WPF. I know about the usual places like Infragistics, but it seems to me that there should be some kind of community effort by now to share nice, clean, well written controls for WPF controls. I am not big on the design side, and it would be nice to fill out my personal libraries with some nice examples from people who are better at design. Any ideas/recommendations?

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  • Is it easy to switch from relational to non-relational databases with Rails?

    - by Tam
    Good day, I have been using Rails/Mysql for the past while but I have been hearing about Cassandra, MongoDB, CouchDB and other document-store DB/Non-relational databases. I'm planning to explore them later as they might be better alternative for scalability. I'm planning to start an application soon. Will it make a different with Rails design if I move from relational to non-relational database? I know Rails migrations are database-agnostic but wasn't sure if moving to non-relational will make difference with design or not.

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  • where should we send notification for updating many views?

    - by Thanh-Cong Vo
    Hi all, I want to ask about software design. I have a task, the view controller handles UI event for calling a model manger to perform that task. After finishing, the model manager will callback to update the view. There have also other views who care about that task, and also want to update its own view when that task is finished. So I register a Notification for that task in each views. The problem is defining where should I send Notification, in Model manager or in the View who handles event and receives the callback from Model manager? What is better design? Shoud the model care about send this "common" task, or shoud the view? Thanks

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  • Normalize or Denormalize in high traffic websites

    - by Inam Jameel
    what is the best practice for database design for high traffic websites like this one stackoverflow? should one must use normalize database for record keeping or normalized technique or combination of both? is it sensible to design normalize database as main database for record keeping to reduce redundancy and at the same time maintain another denormalized form of database for fast searching? or main database should be denormalize and one can make normalized views in the application level for fast database operations? or beside above mentioned approach? what is the best practice of designing high traffic websites???

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  • Best way to fetch data from a single database table with multiple threads?

    - by Ravi Bhatt
    Hi, we have a system where we collect data every second on user activity on multiple web sites. we dump that data into a database X (say MS SQL Server). we now need to fetch data from this single table from daatbase X and insert into database Y (say mySql). we want to fetch time based data from database X through multiple threads so that we fetch as fast as we can. Once fetched and stored in database Y, we will delete data from database X. Are there any best practices on this sort of design? any specific things to take care on table design like sharing or something? Are there any other things that we need to take care to make sure we fetch it as fast as we can from threads running on multiple machines? Thanks in advance! Ravi

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  • Marshalling to a native library in C#

    - by Daniel Baulig
    I'm having trouble calling functions of a native library from within managed C# code. I am developing for the 3.5 compact framework (Windows Mobile 6.x) just in case this would make any difference. I am working with the waveIn* functions from coredll.dll (these are in winmm.dll in regular Windows I believe). This is what I came up with: // namespace winmm; class winmm [StructLayout(LayoutKind.Sequential)] public struct WAVEFORMAT { public ushort wFormatTag; public ushort nChannels; public uint nSamplesPerSec; public uint nAvgBytesPerSec; public ushort nBlockAlign; public ushort wBitsPerSample; public ushort cbSize; } [StructLayout(LayoutKind.Sequential)] public struct WAVEHDR { public IntPtr lpData; public uint dwBufferLength; public uint dwBytesRecorded; public IntPtr dwUser; public uint dwFlags; public uint dwLoops; public IntPtr lpNext; public IntPtr reserved; } public delegate void AudioRecordingDelegate(IntPtr deviceHandle, uint message, IntPtr instance, ref WAVEHDR wavehdr, IntPtr reserved2); [DllImport("coredll.dll")] public static extern int waveInAddBuffer(IntPtr hWaveIn, ref WAVEHDR lpWaveHdr, uint cWaveHdrSize); [DllImport("coredll.dll")] public static extern int waveInPrepareHeader(IntPtr hWaveIn, ref WAVEHDR lpWaveHdr, uint Size); [DllImport("coredll.dll")] public static extern int waveInStart(IntPtr hWaveIn); // some other class private WinMM.WinMM.AudioRecordingDelegate waveIn; private IntPtr handle; private uint bufferLength; private void setupBuffer() { byte[] buffer = new byte[bufferLength]; GCHandle bufferPin = GCHandle.Alloc(buffer, GCHandleType.Pinned); WinMM.WinMM.WAVEHDR hdr = new WinMM.WinMM.WAVEHDR(); hdr.lpData = bufferPin.AddrOfPinnedObject(); hdr.dwBufferLength = this.bufferLength; hdr.dwFlags = 0; int i = WinMM.WinMM.waveInPrepareHeader(this.handle, ref hdr, Convert.ToUInt32(Marshal.SizeOf(hdr))); if (i != WinMM.WinMM.MMSYSERR_NOERROR) { this.Text = "Error: waveInPrepare"; return; } i = WinMM.WinMM.waveInAddBuffer(this.handle, ref hdr, Convert.ToUInt32(Marshal.SizeOf(hdr))); if (i != WinMM.WinMM.MMSYSERR_NOERROR) { this.Text = "Error: waveInAddrBuffer"; return; } } private void setupWaveIn() { WinMM.WinMM.WAVEFORMAT format = new WinMM.WinMM.WAVEFORMAT(); format.wFormatTag = WinMM.WinMM.WAVE_FORMAT_PCM; format.nChannels = 1; format.nSamplesPerSec = 8000; format.wBitsPerSample = 8; format.nBlockAlign = Convert.ToUInt16(format.nChannels * format.wBitsPerSample); format.nAvgBytesPerSec = format.nSamplesPerSec * format.nBlockAlign; this.bufferLength = format.nAvgBytesPerSec; format.cbSize = 0; int i = WinMM.WinMM.waveInOpen(out this.handle, WinMM.WinMM.WAVE_MAPPER, ref format, Marshal.GetFunctionPointerForDelegate(waveIn), 0, WinMM.WinMM.CALLBACK_FUNCTION); if (i != WinMM.WinMM.MMSYSERR_NOERROR) { this.Text = "Error: waveInOpen"; return; } setupBuffer(); WinMM.WinMM.waveInStart(this.handle); } I read alot about marshalling the last few days, nevertheless I do not get this code working. When my callback function is called (waveIn) when the buffer is full, the hdr structure passed back in wavehdr is obviously corrupted. Here is an examlpe of how the structure looks like at that point: - wavehdr {WinMM.WinMM.WAVEHDR} WinMM.WinMM.WAVEHDR dwBufferLength 0x19904c00 uint dwBytesRecorded 0x0000fa00 uint dwFlags 0x00000003 uint dwLoops 0x1990f6a4 uint + dwUser 0x00000000 System.IntPtr + lpData 0x00000000 System.IntPtr + lpNext 0x00000000 System.IntPtr + reserved 0x7c07c9a0 System.IntPtr This obiously is not what I expected to get passed. I am clearly concerned about the order of the fields in the view. I do not know if Visual Studio .NET cares about actual memory order when displaying the record in the "local"-view, but they are obviously not displayed in the order I speciefied in the struct. Then theres no data pointer and the bufferLength field is far to high. Interestingly the bytesRecorded field is exactly 64000 - bufferLength and bytesRecorded I'd expect both to be 64000 though. I do not know what exactly is going wrong, maybe someone can help me out on this. I'm an absolute noob to managed code programming and marshalling so please don't be too harsh to me for all the stupid things I've propably done. Oh here's the C code definition for WAVEHDR which I found here, I believe I might have done something wrong in the C# struct definition: /* wave data block header */ typedef struct wavehdr_tag { LPSTR lpData; /* pointer to locked data buffer */ DWORD dwBufferLength; /* length of data buffer */ DWORD dwBytesRecorded; /* used for input only */ DWORD_PTR dwUser; /* for client's use */ DWORD dwFlags; /* assorted flags (see defines) */ DWORD dwLoops; /* loop control counter */ struct wavehdr_tag FAR *lpNext; /* reserved for driver */ DWORD_PTR reserved; /* reserved for driver */ } WAVEHDR, *PWAVEHDR, NEAR *NPWAVEHDR, FAR *LPWAVEHDR; If you are used to work with all those low level tools like pointer-arithmetic, casts, etc starting writing managed code is a pain in the ass. It's like trying to learn how to swim with your hands tied on your back. Some things I tried (to no effect): .NET compact framework does not seem to support the Pack = 2^x directive in [StructLayout]. I tried [StructLayout(LayoutKind.Explicit)] and used 4 bytes and 8 bytes alignment. 4 bytes alignmentgave me the same result as the above code and 8 bytes alignment only made things worse - but that's what I expected. Interestingly if I move the code from setupBuffer into the setupWaveIn and do not declare the GCHandle in the context of the class but in a local context of setupWaveIn the struct returned by the callback function does not seem to be corrupted. I am not sure however why this is the case and how I can use this knowledge to fix my code. I'd really appreciate any good links on marshalling, calling unmanaged code from C#, etc. Then I'd be very happy if someone could point out my mistakes. What am I doing wrong? Why do I not get what I'd expect.

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  • How are SaaS applications organized?

    - by tomekw
    Consider web (MVC, for example Rails) application for multiple clients as a service. How to design this? one application instance per client? (+ one database per client) one instance for all clients (+ one database for all clients) Former one is simple, but... "inefficient". How about the latter? (best practises, design patterns) How to separate client data? For example: worker "A" of client "1" has two documents, worker "B" of client "2" has three documents. How to build model associations to protect other users (and clients) data? I think joining every query with Client model is not a good solution.

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  • When is referential integrity not appropriate?

    - by Curtis Inderwiesche
    I understand the need to have referential integrity for limiting specific values on entry or possibly preventing them from removal upon a request of deletion. However, I am unclear as to a valid use case which would exclude this mechanism from always being used. I guess this would fall into several sub-questions: When is referential integrity not appropriate? Is it appropriate to have fields containing multiple and/or possibly incomplete subsets of a foreign key's list? Typically, should this be a schema structure design decision or an interface design decision? (Or possibly neither or both) Thoughts?

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  • What is the point in using a "real" database modeling tool?

    - by cdeszaq
    We currently have a 10 year old nasty, spaghetti-code-style SQL Server database that we are soon looking to pretty much re-write from scratch as part of a re-write to a large web application. (The existing application will serve as the functional requirements for the next incarnation of the app). Some have suggested we use Visio to do all the diagramming and to generate the DDL, but others have suggested we use a dedicated database design tool, rather than a diagramming tool that is able to export DDL. Is there any benefit to using "real" DB design tools, such as ModelRight, over general tools like Visio? If so, what are those specific benefits? Edit: In a nutshell, what can real/dedicated tools do that something like Visio can't, and how much do these capabilities matter (from a best-practices standpoint, for example)

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  • A way to avoid deriving from the provider classes in mvc authentication

    - by Shymep
    Looking for the best practice for authentication in MVC I unfortunately didn't find the clear answer to my question. Thinking of the problem I tried to imagine some priciples that could be useful in my design. Well, I would like to use a base AccountController class I want to place all the tables such as "Users", Roles, Rights etc into my own database. But I wouldn't like to implement the standard aspnetdb design (which can be easy got by using aspnet_regsql) So the main question is can I do this without deriving abstract classes like MembershipProvider, RoleProvider etc? What I would prefer not to do is implement all the abstract methods from these classes. The second question is still about the best practice for authentication e.g. for the small projects, for the large ones?

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