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  • Mixed Mode C++ DLL function call failure when app launched from network share. Called from unmanage

    - by Steve
    Mixed-mode DLL called from native C application fails to load: An unhandled exception of type 'System.IO.FileLoadException' occurred in Unknown Module. Additional information: Could not load file or assembly 'XXSharePoint, Version=0.0.0.0, Culture=neutral, PublicKeyToken=e0fbc95fd73fff47' or one of its dependencies. Failed to grant minimum permission requests. (Exception from HRESULT: 0x80131417) My environment is: Native C application calling a mixed mode C++ DLL, which then loads a C# DLL.. This works correctly when loaded from a local drive, but when launched from a network drive, it fails with the above messages. The call to LoadLibrary succeeds, as does the GetProcAddress. The load error happens when I call the function. I have digitally signed the C application, and I've performed "strong name" signing on the 2 DLLs. The PublickKeyToken in the message above does match the named DLL. I have also issued the CASPOLcommands on my client to grant FullTrust to that strong name keytoken. When that failed to work, I tried the CASPOL command to grant FullTrust to the URL of the network drive (including path to my application's directory); no change in results. I tried removing all dependencies, so that there was just the initial mixed-mode DLL... I replaced the bodies of all the functions with just a return of a "success" integer value. Results unchanged. Only when I changed it from Mixed Mode to Win32, and changed the Configuration Properties General Common Language Runtime Support from "Common Language Runtime Support" to "No Common Language Runtime Support" did calling the DLL produce the expected result (just returned the "success" integer return value).

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  • fullcalendar : updating option function callbacks after init

    - by Paul Maneesilasan
    Ok, so I have a problem with setting options whose values are callback functions when I try to set them after plugin initialization. I think this would be a common behavior, to dynamically set event callback after init'ing the calendar. Here is a snipit of code: $(document).ready(function() { $('#calendar').fullCalendar({ editable: false ,events:[{"title":"meeting.title","start":"2010-05-21 15:58:16 UTC"},{"title":"meeting.title","start":"2010-05-24 15:58:16", "url":"http://google.com"}] /* ,eventClick: function(event) { if (event.url) { window.open(event.url); return false; } } */ }); $('#calendar').fullCalendar('options', 'eventClick', function(event) { if (event.url) { window.open(event.url); return false; } }); }); You can see that I have setting the eventClick function as an init option commented out. If I do it that way, it works fine. However if I try to set it after the init, it doesn't work :( Is the some other way to do this? Or am I stuck with having to set the behavior upfront?

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  • Code Golf: Shortest Turing-complete interpreter.

    - by ilya n.
    I've just tried to create the smallest possible language interpreter. Would you like to join and try? Rules of the game: You should specify a programming language you're interpreting. If it's a language you invented, it should come with a list of commands in the comments. Your code should start with example program and data assigned to your code and data variables. Your code should end with output of your result. It's preferable that there are debug statements at every intermediate step. Your code should be runnable as written. You can assume that data are 0 and 1s (int, string or boolean, your choice) and output is a single bit. The language should be Turing-complete in the sense that for any algorithm written on a standard model, such as Turing machine, Markov chains, or similar of your choice, it's reasonably obvious (or explained) how to write a program that after being executred by your interpreter performs the algorithm. The length of the code is defined as the length of the code after removal of input part, output part, debug statements and non-necessary whitespaces. Please add the resulting code and its length to the post. You can't use functions that make compiler execute code for you, such as eval(), exec() or similar. This is a Community Wiki, meaning neither the question nor answers get the reputation points from votes. But vote anyway!

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  • Business Objects - Containers or functional?

    - by Walter
    Where I work, we've gone back and forth on this subject a number of times and are looking for a sanity check. Here's the question: Should Business Objects be data containers (more like DTOs) or should they also contain logic that can perform some functionality on that object. Example - Take a customer object, it probably contains some common properties (Name, Id, etc), should that customer object also include functions (Save, Calc, etc.)? One line of reasoning says separate the object from the functionality (single responsibility principal) and put the functionality in a Business Logic layer or object. The other line of reasoning says, no, if I have a customer object I just want to call Customer.Save and be done with it. Why do I need to know about how to save a customer if I'm consuming the object? Our last two projects have had the objects separated from the functionality, but the debate has been raised again on a new project. Which makes more sense? EDIT These results are very similar to our debates. One vote to one side or another completely changes the direction. Does anyone else want to add their 2 cents? EDIT Eventhough the answer sampling is small, it appears that the majority believe that functionality in a business object is acceptable as long as it is simple but persistence is best placed in a separate class/layer. We'll give this a try. Thanks for everyone's input...

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  • Handling incremental Data Modeling Changes in Functional Programming

    - by Adam Gent
    Most of the problems I have to solve in my job as a developer have to do with data modeling. For example in a OOP Web Application world I often have to change the data properties that are in a object to meet new requirements. If I'm lucky I don't even need to programmatically add new "behavior" code (functions,methods). Instead I can declarative add validation and even UI options by annotating the property (Java). In Functional Programming it seems that adding new data properties requires lots of code changes because of pattern matching and data constructors (Haskell, ML). How do I minimize this problem? This seems to be a recognized problem as Xavier Leroy states nicely on page 24 of "Objects and Classes vs. Modules" - To summarize for those that don't have a PostScript viewer it basically says FP languages are better than OOP languages for adding new behavior over data objects but OOP languages are better for adding new data objects/properties. Are there any design pattern used in FP languages to help mitigate this problem? I have read Phillip Wadler's recommendation of using Monads to help this modularity problem but I'm not sure I understand how?

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  • Works in Firefox & Opera, but not in IE8

    - by Ai Pragma
    1) This issue involves just one html webpage, lets call it "ajax.html".2) I have AJAX functions in this webpage that work in both Firefox and IE8.3) I now attempt generating just the option values of a dropdown list of dates using my ajax functions, and it works in Firefox & Opera, but not IE8.4) The surrounding html code for the dropdown looks like this:<select name="entry_7_single" id="entry_7" onChange="Ajax_PhpResultsWithVar('./secure/db/SummaryCls.php','entry_8','dateval',this.value)"></select>The onchange call refers to an ajax function that successfully(both Firefox & IE8) populates a textarea(entry_8) with a description of an event associated with the date selected in this dropdown. 5) An onload call initiates the ajax function to generate the dropdown list values:<body class="ss-base-body" onLoad="OnLoadWebPage()">6) The js script that calls the ajax function is as follows:function OnLoadWebPage(){    Ajax_PhpResults('./secure/db/GenDateListCls.php','entry_7');}7) Since it works in Firefox, but not IE8, I throw the output of the ajax function into a Firefox large textbox and I get the following:<option selected value="8 JUN 2010">8 JUN 2010</option>                   <option value="9 JUN 2010">9 JUN 2010</option>                   <option value="10 JUN 2010">10 JUN 2010</option>                   <option value="11 JUN 2010">11 JUN 2010</option> 8 ) There are over a hundred generated but you get the gist of what the ajax function generates. Next I will list the PHP function that outputs the above dropdown values://///////////////////////////////////////////////////////////////////////////////////////////////////////<?phpinclude_once 'SPSQLite.class.php';include_once 'misc_funcs.php';class GenDateListCls {    var $dbName;    var $sqlite;        function GenDateListCls()    {        $this->dbName = 'accrsc.db';        $this->ConstructEventDates();    }        function ConstructEventDates()    {         $this->sqlite = new SPSQLite($this->dbName);         $todayarr = getdate();         $today = $todayarr[mday] . " " . substr($todayarr[month],0,3) . " " . $todayarr[year];                  $ICalDate = ChangeToICalDate($today);         $dateQuery = "SELECT dtstart from events where substr(dtstart,1,8) >= '" . $ICalDate . "';";         $this->sqlite->query($dateQuery);         $datesResult = $this->sqlite->returnRows();                      foreach (array_reverse($datesResult) as $indx => $row)         {                       $normDate = NormalizeICalDate(substr($row[dtstart],0,8));              if ($indx==0)              { ?>                 <option selected value=<?php echo('"' . $normDate . '"'); ?>><?php echo $normDate; ?></option><?php                               }                          else              {?>                  <option value=<?php echo('"' . $normDate . '"'); ?>><?php echo $normDate; ?></option><?php                                   }                       }                   $this->sqlite->close();     }}$dateList = new GenDateListCls();    ?>/////////////////////////////////////////////////////////////////////////////////////////////////////////////<<< I appreciate any assistance on this matter. Aipragma >>> My Background: To let you all know, I am a complete newbie to PHP, Ajax, & javascript, and learning it all on my own, no classes. My background is in Linux, Windows, C++, Java, VB,VBA,MS XML, & some html.

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  • Poor LLVM JIT performance

    - by Paul J. Lucas
    I have a legacy C++ application that constructs a tree of C++ objects. I want to use LLVM to call class constructors to create said tree. The generated LLVM code is fairly straight-forward and looks repeated sequences of: ; ... %11 = getelementptr [11 x i8*]* %Value_array1, i64 0, i64 1 %12 = call i8* @T_string_M_new_A_2Pv(i8* %heap, i8* getelementptr inbounds ([10 x i8]* @0, i64 0, i64 0)) %13 = call i8* @T_QueryLoc_M_new_A_2Pv4i(i8* %heap, i8* %12, i32 1, i32 1, i32 4, i32 5) %14 = call i8* @T_GlobalEnvironment_M_getItemFactory_A_Pv(i8* %heap) %15 = call i8* @T_xs_integer_M_new_A_Pvl(i8* %heap, i64 2) %16 = call i8* @T_ItemFactory_M_createInteger_A_3Pv(i8* %heap, i8* %14, i8* %15) %17 = call i8* @T_SingletonIterator_M_new_A_4Pv(i8* %heap, i8* %2, i8* %13, i8* %16) store i8* %17, i8** %11, align 8 ; ... Where each T_ function is a C "thunk" that calls some C++ constructor, e.g.: void* T_string_M_new_A_2Pv( void *v_value ) { string *const value = static_cast<string*>( v_value ); return new string( value ); } The thunks are necessary, of course, because LLVM knows nothing about C++. The T_ functions are added to the ExecutionEngine in use via ExecutionEngine::addGlobalMapping(). When this code is JIT'd, the performance of the JIT'ing itself is very poor. I've generated a call-graph using kcachegrind. I don't understand all the numbers (and this PDF seems not to include commas where it should), but if you look at the left fork, the bottom two ovals, Schedule... is called 16K times and setHeightToAtLeas... is called 37K times. On the right fork, RAGreed... is called 35K times. Those are far too many calls to anything for what's mostly a simple sequence of call LLVM instructions. Something seems horribly wrong. Any ideas on how to improve the performance of the JIT'ing?

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  • How to build Graceful Degradation AJAX web page?

    - by Morgan Cheng
    I want to build web page with "Graceful Degradation". That is, the web page functions even javascript is disabled. Now I have to make design decision on the format of AJAX response. If javascript is disabled, each HTTP request to server will generate HTML as response. The browser refreshes with the returned HTML. That's fine. If javascript is enabled, each AJAX HTTP request to server will generate ... well, JSON or HTML. If it is HTML, it is easy to implement. Just have javascript to replace part of page with the returned HTML. And, in server side, not much code change is needed. If it is JSON, then I have to implement JSON-to-html logic in javascript again which is almost duplicate of server side logic. Duplication is evil. I really don't like it. The benefit is that the bandwidth usage is better than HTML, which brings better performance. So, what's the best solution to Graceful Degradation? AJAX request better to return JSON or HTML?

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  • Convert float to decimal in Informix

    - by prabhu
    I have a table with a column of type decimal. There is a ESQL/C structure that represents the table. It has a member of type decimal. I also have a normal C structure for equivalent for the same table. The type of the above mentioned field is a float. Since we use memcpy to copy data to and from ESQL/C structure to C structure, there is an issue with decimal to float conversion. When I searched the Informix ESQL/C Programmer's manual, I couldn't find any function that can do this. Google search led me to the deccvflt() function. This function converts from a float to a decimal type. Though I couldn't find this function listed in the manual, I see the declarations in decimal.h. Are these functions still recommended to be used? Alternatively, I was also thinking about using the decimal type in the C structure also, as it happens to be a C structure. This way, I can still use the memcpy right? Please share your thoughts. IBM Informix Dynamic Server Version 11.50.FC3 Thanks, prabhu

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  • Replacing .NET WebBrowser control with a better browser, like Chrome?

    - by Sylverdrag
    Is there any relatively easy way to insert a modern browser into a .NET application? As far as I understand, the WebBrowser control is a wrapper for IE, which wouldn't be a problem except that it looks like it is a very old version of IE, with all that entails in terms of CSS screw-ups, potential security risks (if the rendering engine wasn't patched, can I really expect the zillion buffer overflow problems to be fixed?), and other issues. I am using Visual Studio C# (express edition - does it make any difference here?) I would like to integrate a good web browser in my applications. In some, I just use it to handle the user registration process, interface with some of my website's features and other things of that order, but I have another application in mind that will require more err... control. I need: A browser that can integrate inside a window of my application (not a separate window) A good support for CSS, js and other web technologies, on par with any modern browser Basic browser functions like "navigate", "back", "reload"... Liberal access to the page code and output. I was thinking about Chrome, since it comes under the BSD license, but I would be just as happy with a recent version of IE. As much as possible, I would like to keep things simple. The best would be if one could patch the existing WebBrowser control, which does already about 70% of what I need, but I don't think that's possible. I have found an activeX control for Mozilla (http://www.iol.ie/~locka/mozilla/control.htm) but it looks like it's an old version, so it's not necessarily an improvement. I am open to suggestions

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  • Questions about the MVC architecture

    - by ah123
    I started coding a considerably complicated web application, and it became quite a mess. So I figured I'd try to organize it in a better way. MVC seemed appropriate. I've never used MVC before, and researching about it I'm trying to consolidate a better perception of it (and my questions obviously reflect what I think I've learned so far). My questions are slightly JavaScript oriented: What object should make "AJAX" requests? The Controller or the Model? (seperation -- should the Model just store/manipulate the data, should it not care/know where the data came from, or should it be the one fetching it?) Should the Model call View functions providing them with data as arguments or should the View query (reference) the Model within itself? (seperation principles in mind, "the View shouldn't care/know where it gets the data from" -- is that correct?) In general, should the View "know" of the Model's existance, and vice-versa? Is the Controller the only thing gluing them together or is that simply incorrect? (I really doubt that statement is generally correct) There's a good chance I'd want to port this into a desktop/mobile application, so I would like to seperate components in a way that will allow me to achieve that task, replacing the current source of the data, HTTP requests, with DB access, and replacing the View. Maybe every approach that I've asked about is still "valid" MVC and it's just up to me to choose. I understand that nothing is set in stone, I'm just trying to have a (better) general idea in my head.

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  • How can I round money values to the nearest $5.00 interval?

    - by Frank Developer
    I have an Informix-SQL based Pawnshop app which calculates an estimate of how much money should be loaned to a customer, based on the weight and purity of gold. The minimum the pawnshop lends is $5.00. The pawnshop employee will typically lend amounts which either ends with a 5 or 0. examples: 10, 15, 20, 100, 110, 125, etc. They do this so as to not run into shortage problems with $1.00 bills. So, if for example my system calculates the loan should be: $12.49, then round it to $10, $12.50 to $15.00, $13.00 to $15.00, $17.50 to $20.00, and so on!..The employee can always override the rounded amount if necessary. Is it possible to accomplish this within the instructions section of a perform screen or would I have to write a cfunc and call it from within perform?.. Are there any C library functions which perform interval rounding of money values?.. On another note, I think the U.S. Government should discontinue the use of pennies so that businesses can round amounts to the nearest nickel, it would save so much time and weight in our pockets!

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  • What is Ruby's analog to Python Metaclasses?

    - by Sean Copenhaver
    Python has the idea of metaclasses that, if I understand correctly, allow you to modify an object of a class at the moment of construction. You are not modifying the class, but instead the object that is to be created then initialized. Python (at least as of 3.0 I believe) also has the idea of class decorators. Again if I understand correctly, class decorators allow the modifying of the class definition at the moment it is being declared. Now I believe there is an equivalent feature or features to the class decorator in Ruby, but I'm currently unaware of something equivalent to metaclasses. I'm sure you can easily pump any Ruby object through some functions and do what you will to it, but is there a feature in the language that sets that up like metaclasses do? So again, Does Ruby have something similar to Python's metaclasses? Edit I was off on the metaclasses for Python. A metaclass and a class decorator do very similar things it appears. They both modify the class when it is defined but in different manners. Hopefully a Python guru will come in and explain better on these features in Python. But a class or the parent of a class can implement a __new__(cls[,..]) function that does customize the construction of the object before it is initialized with __init__(self[,..]).

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  • MySQL table data transformation -- how can I dis-aggregate MySQL time data?

    - by lighthouse65
    We are coding for a MySQL data warehousing application that stores descriptive data (User ID, Work ID, Machine ID, Start and End Time columns in the first table below) associated with time and production quantity data (Output and Time columns in the first table below) upon which aggregate (SUM, COUNT, AVG) functions are applied. We now wish to dis-aggregate time data for another type of analysis. Our current data table design: +---------+---------+------------+---------------------+---------------------+--------+------+ | User ID | Work ID | Machine ID | Event Start Time | Event End Time | Output | Time | +---------+---------+------------+---------------------+---------------------+--------+------+ | 080025 | ABC123 | M01 | 2008-01-24 16:19:15 | 2008-01-24 16:34:45 | 2120 | 930 | +---------+---------+------------+---------------------+---------------------+--------+------+ Reprocessing dis-aggregation that we would like to do would be to transform table content based on a granularity of minutes, rather than the current production event ("Event Start Time" and "Event End Time") granularity. The resulting reprocessing of existing table rows would look like: +---------+---------+------------+---------------------+--------+ | User ID | Work ID | Machine ID | Production Minute | Output | +---------+---------+------------+---------------------+--------+ | 080025 | ABC123 | M01 | 2010-01-24 16:19 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:20 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:21 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:22 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:23 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:24 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:25 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:26 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:27 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:28 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:29 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:30 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:31 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:22 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:33 | 133 | | 080025 | ABC123 | M01 | 2010-01-24 16:34 | 133 | +---------+---------+------------+---------------------+--------+ So the reprocessing would take an existing row of data created at the granularity of production event and modify the granularity to minutes, eliminating redundant (Event End Time, Time) columns while doing so. It assumes a constant rate of production and divides output by the difference in minutes plus one to populate the new table's Output column. I know this can be done in code...but can it be done entirely in a MySQL insert statement (or otherwise entirely in MySQL)? I am thinking of a INSERT ... INTO construction but keep getting stuck. An additional complexity is that there are hundreds of machines to include in the operation so there will be multiple rows (one for each machine) for each minute of the day. Any ideas would be much appreciated. Thanks.

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  • Flex - Increase timeout on a PHP service function call

    - by Travesty3
    I'm using Flash Builder 4 Beta 2. I have it connecting to a PHP service. The way I set this up was using the wizard, so I didn't actually write the code to connect to it. The service looks like this: package services.flash { import mx.rpc.AsyncToken; import com.adobe.fiber.core.model_internal; import mx.rpc.AbstractOperation; import valueObjects.CustomDatatype8; import valueObjects.NewUsageData; import mx.collections.ItemResponder; import mx.rpc.remoting.RemoteObject; import mx.rpc.remoting.Operation; import com.adobe.fiber.services.wrapper.RemoteObjectServiceWrapper; import com.adobe.fiber.valueobjects.AvailablePropertyIterator; import com.adobe.serializers.utility.TypeUtility; [ExcludeClass] internal class _Super_FLASH extends RemoteObjectServiceWrapper { // Constructor public function _Super_FLASH() { // initialize service control _serviceControl = new RemoteObject(); var operations:Object = new Object(); var operation:Operation; operation = new Operation(null, "sendCommand"); operation.resultType = Object; operations["sendCommand"] = operation; ... } } One of the functions that I'm calling fetches users from a MySQL database. There are about 30,000 users right now. The service seems to timeout when fetching more than around 22,000 rows, I get the "Channel Disconnected before an acknowledgement was received" error. If I call the PHP script from a browser, it fetches them all with no problems at all, however. I have tried increasing the timeout in the PHP script (which didn't work), but obviously this isn't the problem since the browser is able to pull them up with no problems. Is there a way to increase the timeout of the PHP service in Flash Builder? I'm a bit of a noob when it comes to Flash, so please be descriptive. Thanks in advance!

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  • Buttons OnClick Event not firing when it causes a textboxes onChange event to fire first

    - by user48408
    I have a few textboxes and button to save their values on a webpage. The onchange event of the textboxes fires some js which adds the changed text to a js array. The ok button when clicked flushes this to the database via a webservice. This works fine except when the onchange event is caused by clicking the ok button. In this scenario the onchange of the textboxes still fires but the onClick event of the button does not. Any ideas? textboxes look something like <input name="ctrlJPView$tbcTabContainer$Details$JP_Details_Address2Text" type="text" value="test" id="ctrlJPView_tbcTabContainer_Details_JP_Details_Address2Text" onchange="addSaveDetails('Jobs###' + document.getElementById('ctrlJPView_tbcTabContainer_Details_JP_Details_Address2Text').value + ');" style="font-size:8pt;Left:110px;Top:29px;Width:420px;Height:13px;Position:absolute;" /> My save button <input type="button" name="ctrlJPView$btnOk" value="OK" onclick="saveAmendments();refreshJobGrids();return false;__doPostBack('ctrlJPView$btnOk','')" id="ctrlJPView_btnOk" class="ControlText" style="width:60px;" /> UPDATE: I guess this comes down to one of two things. 1) Something is happening before the onClick of the button gets called to surpress that call such as an inadvertent return false; or 2) the onClick event isn't firing at all. Now I've rem'd out everything actually inside the functions that are being called beforehand but the problem persists. But if i remove the call altogether it works (???)

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  • Why is execution-time method resolution faster than compile-time resolution?

    - by Felix
    At school, we about virtual functions in C++, and how they are resolved (or found, or matched, I don't know what the terminology is -- we're not studying in English) at execution time instead of compile time. The teacher also told us that compile-time resolution is much faster than execution-time (and it would make sense for it to be so). However, a quick experiment would suggest otherwise. I've built this small program: #include <iostream> #include <limits.h> using namespace std; class A { public: void f() { // do nothing } }; class B: public A { public: void f() { // do nothing } }; int main() { unsigned int i; A *a = new B; for (i=0; i < UINT_MAX; i++) a->f(); return 0; } Where I made A::f() once normal, once virtual. Here are my results: [felix@the-machine C]$ time ./normal real 0m25.834s user 0m25.742s sys 0m0.000s [felix@the-machine C]$ time ./virtual real 0m24.630s user 0m24.472s sys 0m0.003s [felix@the-machine C]$ time ./normal real 0m25.860s user 0m25.735s sys 0m0.007s [felix@the-machine C]$ time ./virtual real 0m24.514s user 0m24.475s sys 0m0.000s [felix@the-machine C]$ time ./normal real 0m26.022s user 0m25.795s sys 0m0.013s [felix@the-machine C]$ time ./virtual real 0m24.503s user 0m24.468s sys 0m0.000s There seems to be a steady ~1 second difference in favor of the virtual version. Why is this? Relevant or not: dual-core pentium @ 2.80Ghz, no extra applications running between two tests. Archlinux with gcc 4.5.0. Compiling normally, like: $ g++ test.cpp -o normal Also, -Wall doesn't spit out any warnings, either.

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  • Design suggestion for expression tree evaluation with time-series data

    - by Lirik
    I have a (C#) genetic program that uses financial time-series data and it's currently working but I want to re-design the architecture to be more robust. My main goals are: sequentially present the time-series data to the expression trees. allow expression trees to access previous data rows when needed. to optimize performance of the data access while evaluating the expression trees. keep a common interface so various types of data can be used. Here are the possible approaches I've thought about: I can evaluate the expression tree by passing in a data row into the root node and let each child node use the same data row. I can evaluate the expression tree by passing in the data row index and letting each node get the data row from a shared DataSet (currently I'm passing the row index and going to multiple synchronized arrays to get the data). Hybrid: an immutable data set is accessible by all of the expression trees and each expression tree is evaluated by passing in a data row. The benefit of the first approach is that the data row is being passed into the expression tree and there is no further query done on the data set (which should increase performance in a multithreaded environment). The drawback is that the expression tree does not have access to the rest of the data (in case some of the functions need to do calculations using previous data rows). The benefit of the second approach is that the expression trees can access any data up to the latest data row, but unless I specify what that row is, I'll have to iterate through the rows and figure out which one is the last one. The benefit of the hybrid is that it should generally perform better and still provide access to the earlier data. It supports two basic "views" of data: the latest row and the previous rows. Do you guys know of any design patterns or do you have any tips that can help me build this type of system? Should I use a DataSet to hold and present the data, or are there more efficient ways to present rows of data while maintaining a simple interface? FYI: All of my code is written in C#.

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  • Setting Position of source and listener has no effect

    - by Ben E
    Hi Guys, First time i've worked with OpenAL, and for the life of my i can't figure out why setting the position of the source doesn't have any effect on the sound. The sounds are in stero format, i've made sure i set the listener position, the sound is not realtive to the listener and OpenAL isn't giving out any error. Can anyone shed some light? Create Audio device ALenum result; mDevice = alcOpenDevice(NULL); if((result = alGetError()) != AL_NO_ERROR) { std::cerr << "Failed to create Device. " << GetALError(result) << std::endl; return; } mContext = alcCreateContext(mDevice, NULL); if((result = alGetError()) != AL_NO_ERROR) { std::cerr << "Failed to create Context. " << GetALError(result) << std::endl; return; } alcMakeContextCurrent(mContext); SoundListener::SetListenerPosition(0.0f, 0.0f, 0.0f); SoundListener::SetListenerOrientation(0.0f, 0.0f, -1.0f); The two listener functions call alListener3f(AL_POSITION, x, y, z); Real vec[6] = {x, y, z, 0.0f, 1.0f, 0.0f}; alListenerfv(AL_ORIENTATION, vec); I set the sources position to 1,0,0 which should be to the right of the listener but it has no effect alSource3f(mSourceHandle, AL_POSITION, x, y, z); Any guidance would be much appreciated

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  • Boost class/struct serialization to byte array

    - by Dave18
    does boost library provide functions to pack the class/struct data into a byte array to shorten the length of serialized data? Currently i'm using stringstream to get the serialized data, for example - struct data { std::string s1; std::string s2; int i; }; template <typename Archive> void serialize(Archive &ar, data &d, const unsigned int version) { ar & d.s1; ar & d.s2; ar & d.i; } int main() { data d; d.s1 = "This is my first string"; d.s2 = "This is my second string"; d.i = 10000; std::stringstream archive_stream; boost::archive::text_oarchive archive(archive_stream); archive.operator <<(d); } How would i use a byte array instead of stringstream for data?

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  • What's better practice: objc_msgSendv or NSInvocation?

    - by Jared P
    So I'm working on something in obj-c (I'd rather not say what) where I need to be able to call arbitrary methods on arbitrary objects with arbitrary variables. The first two are easy enough to do, but I am unsure how to do the variable arguments. To be clear, this is not about a function/method receiving variable arguments, but about sending them. I have found two ways to do this: objc_msgSendv (and its variants) in the objective-c runtime, and NSInvocation. NSInvocation seems easier and more like it's the 'best practice', but objc_msgSendv sounds like it should be faster, and I need to do this many, many times over, with completely different messages each time. Which one should I choose? Is objc_msgSendv taboo for a good reason? (the docs say not to call the objc_msgsend functions.) P.S. I know the types of all the arguments, and not all of them are id-s Also, (not part of the main question,) there doesn't appear to be a way to message super from objc_msgSendv, but there doesn't seem to be a way to do that in NSInvocation either, so any help on that would be great too.

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  • Prototype VS jQuery

    - by aSeptik
    Hi All guys! First of, thank's for your time; then i want go directly to the point by saying that, i don't want to open another "Yet Another Js VS Js" 3d , the web is almost busy of this! I want also make a premise, i have used both theese js frameworks and i love it and i know, that there are a lot of good js frameworks around, maybe better then this two; but, as you know we need to be perfomant and quickly by doing our works, so i want keep this two, that are the most famous and therefore have a great community support! now, if you are going to say me, that the choise depends on what i'm going to do!? then i can think, hey, in the end they are both javascript and they have almost the same methods and functions and for achieve a task they needs almost the same lines of code! So i want hear from you guys, from you that have really used one of theese, for a real Rich Internet Application what are the real points of force and what the weaknesses you find!? Regards.

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  • question regarding templatization of virtual function

    - by jan
    Hi, I am new to this forum and sorry If I am repeating this question. I know that you cannot templatize the virtual function and I do understand the concept behind it. But I still need a way to get across some errors I am getting it. I am able to make my stuff work but it doesn't look to me. Here's the deal, I have class called System, #include "Vector.h" class System { virtual void VectorToLocal(Vector<T>& global_dir,const Vector<T>* global_pos = 0) const = 0; }; class UnresolvedSystem : public System { virtual void VectorToLocal(Vector<T>& global_dir,const Vector<T>* global_pos = 0) const { //do something } }; In Vector.h tenplate<typename T> class Vector { //some functions }; See now I want to templatize VectorToLocal in system.h to take just Vector, but I cannot do it as it is a virtual function. I want a work around. I know I can have VectorToLocal take Vector, Vector etc as arguments. But I do not want to do it. Any help would be really appreciated. Thanks in advance, Jan

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  • How to insert an Array/Objet into SQL (bestpractice)

    - by Jason
    I need to store three items as an array in a single column and be able to quickly/easily modify that data in later functions. [---YOU CAN SKIP THIS PART IF YOU TRUST ME--] To be clear, I love and use x_ref tables all the time but an x_ref doesn't work here because this is not a one-to-many relationship. I am making a project management tool that among other things, assigns a user to a project and assigns hours to that project on a weekly basis, per user, sometimes for weeks many weeks into the future. Of course there are many projects, a project can have many team members, a team member can be involved with many projects at one time BUT its not one-to-many because a team member can be working many weeks on the same project but have different hours for different weeks. In other words, each object really is unique. Also/finally, this data can be changed at any time by any team-member - hence it needs to be easily to manipulate. Basically, I need to handle three values (the team member, the week we're talking about, and how many hours) dropped into a project row in the projects table (under the column for project team members) and treated as one item - a team member - that will actually be part of a larger array of all the team members involved on the project. [--END SKIP, START READING HERE :) --] So assuming that the application's general schema and relation tables aren't total crap and that we are in fact up against a wall in this one case to use an array/object as a value for this column, is there a best practice for that? Like a particular SQL data-type? A particular object/array format? CSV? JSON? XML? Most of the app is in C# but (for very odd reasons that I won't explain) we could really use any environment if there is a particular one that handles this well. For the moment, I am thinking either (webservice + JS/JSON) or PHP unserialize/serialize (but I am bit sketched out by the PHP solution because it seems a bit cumbersome when using ajax?) Thoughts anyone?

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  • java class creation dynamically and make it accessible across the network different jvms i.e. serial

    - by inj.rav
    Hi. I have a requirement of creating java classes dynamically and make it accessible different jvms across the network. I tried to use reflection and javassist tool,but nothing worked. Let me explain the scenario we are using Coherence distributed cache. It has a power of doing aggregation/filtering in parallel across the cluster. For example if a class has [dynamic class] has amount variable and getAmount/setAmount methods. Then if we execute COHERENCE queries, it will start process in parallel across the cluster. I tried to create classes at run time by using javassist and reflection. I am able to access it from single JVM, but when I tried to access the same class from other jvm [through coherence cluster]. I am getting exception of class not found [as remote jvm is not having idea of this class].I can over come this by creating same class dynamically on remote jvm also and access the methods. But coherence in built methods/functions are not able to find the class. could some one help me on this matter

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