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  • structure inside structure - c++ Error

    - by gamadeus
    First of all the error I am getting is of the type: Request for member 's' of struct1.struct1::struct2, which is of non class type '__u32' where: struct struct1 { struct x struct2; struct x struct3; struct x struct4; }; The usage is of the form: struct struct1 st1; st1.struct2.s = Value; Now my struct1 is: struct ip_mreq_source { struct in_addr imr_multiaddr; struct in_addr imr_sourceaddr; struct in_addr imr_interface; }; struct 'x' is in_addr Where: typedef uint32_t in_addr_t; struct in_addr { in_addr_t s_addr; }; element 's' is the element s_addr in in_addr. My detailed error coming out of g++ (GCC 4.4.3) from the Android based compiler: arm-linux-androideabi-g++ -MMD -MP -MF groupsock/GroupsockHelper.o.d.org -fpic -ffunction-sections -funwind-tables -fstack-protector -D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ -Wno-psabi -march=armv5te -mtune=xscale -msoft-float -fno-exceptions -fno-rtti -mthumb -Os -fomit-frame-pointer -fno-strict-aliasing -finline- limit=64 -Igroupsock/include -Igroupsock/../UsageEnvironment/include -Iandroid- ndk-r5b/sources/cxx-stl/system/include -Igroupsock -DANDROID -Wa,--noexecstack -DANDROID_NDK -Wall -fexceptions -O2 -DNDEBUG -g -Iandroid-8/arch-arm/usr/include -c groupsock/GroupsockHelper.cpp -o groupsock/GroupsockHelper.o && rm -f groupsock/GroupsockHelper.o.d && mv groupsock/GroupsockHelper.o.d.org groupsock/GroupsockHelper.o.d groupsock/GroupsockHelper.cpp: In function 'Boolean socketJoinGroupSSM(UsageEnvironment&, int, netAddressBits, netAddressBits)': groupsock/GroupsockHelper.cpp:427: error: request for member 's_addr' in 'imr.ip_mreq_source::imr_multiaddr', which is of non-class type '__u32' groupsock/GroupsockHelper.cpp:428: error: request for member 's_addr' in 'imr.ip_mreq_source::imr_sourceaddr', which is of non-class type '__u32' groupsock/GroupsockHelper.cpp:429: error: request for member 's_addr' in 'imr.ip_mreq_source::imr_interface', which is of non-class type '__u32' I am not sure what is causing the error. Any pointers would be great - no pun intended. Thanks

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  • How can I make this method more Scalalicious

    - by Neil Chambers
    I have a function that calculates the left and right node values for some collection of treeNodes given a simple node.id, node.parentId association. It's very simple and works well enough...but, well, I am wondering if there is a more idiomatic approach. Specifically is there a way to track the left/right values without using some externally tracked value but still keep the tasty recursion. /* * A tree node */ case class TreeNode(val id:String, val parentId: String){ var left: Int = 0 var right: Int = 0 } /* * a method to compute the left/right node values */ def walktree(node: TreeNode) = { /* * increment state for the inner function */ var c = 0 /* * A method to set the increment state */ def increment = { c+=1; c } // poo /* * the tasty inner method * treeNodes is a List[TreeNode] */ def walk(node: TreeNode): Unit = { node.left = increment /* * recurse on all direct descendants */ treeNodes filter( _.parentId == node.id) foreach (walk(_)) node.right = increment } walk(node) } walktree(someRootNode) Edit - The list of nodes is taken from a database. Pulling the nodes into a proper tree would take too much time. I am pulling a flat list into memory and all I have is an association via node id's as pertains to parents and children. Adding left/right node values allows me to get a snapshop of all children (and childrens children) with a single SQL query. The calculation needs to run very quickly in order to maintain data integrity should parent-child associations change (which they do very frequently). In addition to using the awesome Scala collections I've also boosted speed by using parallel processing for some pre/post filtering on the tree nodes. I wanted to find a more idiomatic way of tracking the left/right node values. After looking at the answers listed I have settled on this synthesised version: def walktree(node: TreeNode) = { def walk(node: TreeNode, counter: Int): Int = { node.left = counter node.right = treeNodes .filter( _.parentId == node.id) .foldLeft(counter+1) { (counter, curnode) => walk(curnode, counter) + 1 } node.right } walk(node,1) }

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  • learning to type - tips for programmers?

    - by OrbMan
    After hunting and pecking for about 35 years, I have decided to learn to type. I am learning QWERTY and have learned about 2/3 of the letters so far. While learning, I have noticed how asymmeterical the keyboard is, which really bothers me. (I will probably switch to a symmetrical keyboard eventually, but for now am trying to do everything as standard and "correct" as possible.) Although I am not there yet in my lessons, it seems that many of the keys I am going to use as a C# web developer are supposed to be typed by the pinky of my right hand. Are there any typing patterns you have developed that are more ergonomic (or faster) when typing large volumes of code rife with braces, colons, semi-colons and quotes? Or, should I just accept the fact that every other key is going to be hit with my right pinky? It is not that speed is such a huge concern, as much as that it seems so inefficient to rely on one finger so much... As an example, some of the conventions I use as a hunt and pecker, like typing open and close braces right away with my index and middle finger, and then hitting the left arrow key to fill in the inner content, don't seem to work as well with just a pinky. What are some typing patterns using a standard QWERTY keyboard that work really well for you as a programmer?

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  • Link checker ; how to avoid false positives

    - by Burnzy
    I'm working a on a link checker/broken link finder and I am getting many false positives, after double checking I noticed that many error codes were returning webexceptions but they were actually downloadable, but in some other cases the statuscode is 404 and i can access the page from the browse. So here is the code, its pretty ugly, and id like to have something more, id say practical. All the status codes are in that big if are used to filter the ones i dont want to add to brokenlink because they are valid links ( i tested them all ). What i need to fix is the structure (if possible) and how to not get false 404. Thank you! try { HttpWebRequest request = ( HttpWebRequest ) WebRequest.Create ( uri ); request.Method = "Head"; request.MaximumResponseHeadersLength = 32; // FOR IE SLOW SPEED request.AllowAutoRedirect = true; using ( HttpWebResponse response = ( HttpWebResponse ) request.GetResponse() ) { request.Abort(); } /* WebClient wc = new WebClient(); wc.DownloadString( uri ); */ _validlinks.Add ( strUri ); } catch ( WebException wex ) { if ( !wex.Message.Contains ( "The remote name could not be resolved:" ) && wex.Status != WebExceptionStatus.ServerProtocolViolation ) { if ( wex.Status != WebExceptionStatus.Timeout ) { HttpStatusCode code = ( ( HttpWebResponse ) wex.Response ).StatusCode; if ( code != HttpStatusCode.OK && code != HttpStatusCode.BadRequest && code != HttpStatusCode.Accepted && code != HttpStatusCode.InternalServerError && code != HttpStatusCode.Forbidden && code != HttpStatusCode.Redirect && code != HttpStatusCode.Found ) { _brokenlinks.Add ( new Href ( new Uri ( strUri , UriKind.RelativeOrAbsolute ) , UrlType.External ) ); } else _validlinks.Add ( strUri ); } else _brokenlinks.Add ( new Href ( new Uri ( strUri , UriKind.RelativeOrAbsolute ) , UrlType.External ) ); } else _validlinks.Add ( strUri ); }

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  • Use a vector to index a matrix without linear index

    - by David_G
    G'day, I'm trying to find a way to use a vector of [x,y] points to index from a large matrix in MATLAB. Usually, I would convert the subscript points to the linear index of the matrix.(for eg. Use a vector as an index to a matrix in MATLab) However, the matrix is 4-dimensional, and I want to take all of the elements of the 3rd and 4th dimensions that have the same 1st and 2nd dimension. Let me hopefully demonstrate with an example: Matrix = nan(4,4,2,2); % where the dimensions are (x,y,depth,time) Matrix(1,2,:,:) = 999; % note that this value could change in depth (3rd dim) and time (4th time) Matrix(3,4,:,:) = 888; % note that this value could change in depth (3rd dim) and time (4th time) Matrix(4,4,:,:) = 124; Now, I want to be able to index with the subscripts (1,2) and (3,4), etc and return not only the 999 and 888 which exist in Matrix(:,:,1,1) but the contents which exist at Matrix(:,:,1,2),Matrix(:,:,2,1) and Matrix(:,:,2,2), and so on (IRL, the dimensions of Matrix might be more like size(Matrix) = (300 250 30 200) I don't want to use linear indices because I would like the results to be in a similar vector fashion. For example, I would like a result which is something like: ans(time=1) 999 888 124 999 888 124 ans(time=2) etc etc etc etc etc etc I'd also like to add that due to the size of the matrix I'm dealing with, speed is an issue here - thus why I'd like to use subscript indices to index to the data. I should also mention that (unlike this question: Accessing values using subscripts without using sub2ind) since I want all the information stored in the extra dimensions, 3 and 4, of the i and jth indices, I don't think that a slightly faster version of sub2ind still would not cut it..

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  • How to use boost::bind with non-copyable params, for example boost::promise ?

    - by zhengxi
    Some C++ objects have no copy constructor, but have move constructor. For example, boost::promise. How can I bind those objects using their move constructors ? #include <boost/thread.hpp> void fullfil_1(boost::promise<int>& prom, int x) { prom.set_value(x); } boost::function<void()> get_functor() { // boost::promise is not copyable, but movable boost::promise<int> pi; // compilation error boost::function<void()> f_set_one = boost::bind(&fullfil_1, pi, 1); // compilation error as well boost::function<void()> f_set_one = boost::bind(&fullfil_1, std::move(pi), 1); // PS. I know, it is possible to bind a pointer to the object instead of // the object itself. But it is weird solution, in this case I will have // to take cake about lifetime of the object instead of delegating that to // boost::bind (by moving object into boost::function object) // // weird: pi will be destroyed on leaving the scope boost::function<void()> f_set_one = boost::bind(&fullfil_1, boost::ref(pi), 1); return f_set_one; }

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  • jQuery .attr() crashing Internet Explorer

    - by Sunyatasattva
    Hello everyone, This is my first time posting a question here, as I usually try to find solutions myself. This one, though, being an IE issue, just drives me crazy. I use jQuery cycle plug-in on a website I made and, to populate a caption div, I use a little function that is called after the image is loaded, which uses the "alt" attribute of the image. This seems to exasperate Internet Explorer, which, doesn't have the time to fulfill this apparently so-complicated task, and, as the slideshow cycles, it enters in an infinite loop and eventually crashes – the newer the version, the worse the crash: the older IEs just display an error message saying “The webpage cannot be displayed”, while the newer (7 and 8) completely crash the system. I have no idea on how to solve or work around this. Here is the problematic code. function changeCaption() { var caption = $("img", this).attr("alt"); $('#caption').fadeIn("slow").html(caption); } Thanks in advance for any pointer: I am amazed as how something so simple and globally recognized (didn't encounter any other browser who had problem with this), can cause a problem so big. I also read somewhere that being able to crash a browser remotely is a serious issue :) Lucio

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  • Which linear programming package should I use for high numbers of constraints and "warm starts"

    - by davidsd
    I have a "continuous" linear programming problem that involves maximizing a linear function over a curved convex space. In typical LP problems, the convex space is a polytope, but in this case the convex space is piecewise curved -- that is, it has faces, edges, and vertices, but the edges aren't straight and the faces aren't flat. Instead of being specified by a finite number of linear inequalities, I have a continuously infinite number. I'm currently dealing with this by approximating the surface by a polytope, which means discretizing the continuously infinite constraints into a very large finite number of constraints. I'm also in the situation where I'd like to know how the answer changes under small perturbations to the underlying problem. Thus, I'd like to be able to supply an initial condition to the solver based on a nearby solution. I believe this capability is called a "warm start." Can someone help me distinguish between the various LP packages out there? I'm not so concerned with user-friendliness as speed (for large numbers of constraints), high-precision arithmetic, and warm starts. Thanks!

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  • What would cause native gem extensions on OS X to build but fail to load?

    - by goodmike
    I am having trouble with some of my rubygems, in particular those that use native extensions. I am on a MacBookPro, with Snow Leopard. I have XCode 3.2.1 installed, with gcc 4.2.1. Ruby 1.8.6, because I'm lazy and a scaredy cat and don't want to upgrade yet. Ruby is running in 32-bit mode. I built this ruby from scratch when my MBP ran OSX 10.4. When I require one of the affected gems in irb, I get a Load Error for the gem extension's bundle file. For example, here's nokogigi dissing me: > require 'rubygems' = true > require 'nokogiri' LoadError: Failed to load /usr/local/lib/ruby/gems/1.8/gems/nokogiri-1.4.1/lib/nokogiri/nokogiri.bundle This is also happening with the Postgres pg and MongoDB mongo gems. My first thought was that the extensions must not be building right. But gem install wasn't throwing any errors. So I reinstalled with the verbose flag, hoping to see some helpful warnings. I've put the output in a Pastie, and the only warning I see is a consistent one about "passing argument n of ‘foo’ with different width due to prototype." I suspect that this might be an issue from upgrading to Snow Leopard, but I'm a little surprised to experience it now, since I've updated my XCode. Could it stem from running Ruby in 1.8.6? I'm embarrassed that I don't know quite enough about my Mac and OSX to know where to look next, so any guidance, even just a pointer to some document I couldn't find via Google, would be most welcome. Michael

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  • algorithm || method to write prog

    - by fatai
    I am one of the computer science student. My wonder is everyone solve problem with different or same method, but actually I dont know whether they use method or I dont know whether there are such common method to approach problem. All teacher give us problem which in simple form sometimes, but they dont introduce any approach or method(s) so that we can first choose method then apply that one to problem , afterward find solution then write code. I have found one method when I failed the course, More accurately, When I counter problem in language , I will get more paper and then ; first, input/ output step ; my prog will take this / these there argument(s) and return namely X , ex : in c, input length is not known and at same type , so I must use pointer desired output is in form of package , so use structure second, execution part ; in that step , I am writing all step which are goes to final output ex : in python ; 1.) [ + , [- , 4 , [ * , 1 , 2 ]], 5] 2.) [ + , [- , 4 , 2 ],5 ] 3.) [ + , 2 , 5] 4.) 7 ==> return 7 third, I will write test code ex : in c++ input : append 3 4 5 6 vector_x remove 0 1 desired output vector_x holds : 5 6 But now, I wonder other method ; used to construct class :::: for c++ , python, java used to communicate classes / computers used for solving embedded system problem ::::: for c Why I wonder , because I learn if you dont costruct algorithm on paper, you may achieve your goal. Like no money no lunch , I can say no algorithm no prog therefore , feel free when you write your own method , a way which is introduced by someone else but you are using and you find it is so efficient

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  • jQuery accordion - different image for active sections

    - by Andrew Cassidy
    Hi, I'm using Ryan Stemkoski's "Stupid Simple Jquery Accordion Menu" which is available here: stemkoski.com/stupid-simple-jquery-accordion-menu/ Here is the javascript $(document).ready(function() { //ACCORDION BUTTON ACTION (ON CLICK DO THE FOLLOWING) $('.accordionButton').click(function() { //REMOVE THE ON CLASS FROM ALL BUTTONS $('.accordionButton').removeClass('on'); //NO MATTER WHAT WE CLOSE ALL OPEN SLIDES $('.accordionContent').slideUp('normal'); //IF THE NEXT SLIDE WASN'T OPEN THEN OPEN IT if($(this).next().is(':hidden') == true) { //ADD THE ON CLASS TO THE BUTTON $(this).addClass('on'); //OPEN THE SLIDE $(this).next().slideDown('normal'); } }); /*** REMOVE IF MOUSEOVER IS NOT REQUIRED ***/ //ADDS THE .OVER CLASS FROM THE STYLESHEET ON MOUSEOVER $('.accordionButton').mouseover(function() { $(this).addClass('over'); //ON MOUSEOUT REMOVE THE OVER CLASS }).mouseout(function() { $(this).removeClass('over'); }); /*** END REMOVE IF MOUSEOVER IS NOT REQUIRED ***/ /******************************************************************************************************************** CLOSES ALL S ON PAGE LOAD ********************************************************************************************************************/ $('.accordionContent').hide(); }); and the CSS #wrapper { width: 800px; margin-left: auto; margin-right: auto; } .accordionButton { width: 800px; float: left; _float: none; /* Float works in all browsers but IE6 */ background: #003366; border-bottom: 1px solid #FFFFFF; cursor: pointer; } .accordionContent { width: 800px; float: left; _float: none; /* Float works in all browsers but IE6 */ background: #95B1CE; } /*********************************************************************************************************************** EXTRA STYLES ADDED FOR MOUSEOVER / ACTIVE EVENTS ************************************************************************************************************************/ .on { background: #990000; } .over { background: #CCCCCC; } There is an "on" class which allows the style of the accordionButton class when it is active but I would like to be able to have each active accordionButton class have a different image. http://www.thepool.ie For example, in the above site the word "WORK" should be a darker grey image when the work section is selected, so should COLLAB when it is selected etc. I can't figure out how to do this, any help would be greatly appreciated. Thanks, Andrew

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  • SQL Server insert performance

    - by Jose
    I have an insert query that gets generated like this INSERT INTO InvoiceDetail (LegacyId,InvoiceId,DetailTypeId,Fee,FeeTax,Investigatorid,SalespersonId,CreateDate,CreatedById,IsChargeBack,Expense,RepoAgentId,PayeeName,ExpensePaymentId,AdjustDetailId) VALUES(1,1,2,1500.0000,0.0000,163,1002,'11/30/2001 12:00:00 AM',1116,0,550.0000,850,NULL,@ExpensePay1,NULL); DECLARE @InvDetail1 INT; SET @InvDetail1 = (SELECT @@IDENTITY); This query is generated for only 110K rows. It takes 30 minutes for all of these query's to execute I checked the query plan and the largest % nodes are A Clustered Index Insert at 57% query cost which has a long xml that I don't want to post. A Table Spool which is 38% query cost <RelOp AvgRowSize="35" EstimateCPU="5.01038E-05" EstimateIO="0" EstimateRebinds="0" EstimateRewinds="0" EstimateRows="1" LogicalOp="Eager Spool" NodeId="80" Parallel="false" PhysicalOp="Table Spool" EstimatedTotalSubtreeCost="0.0466109"> <OutputList> <ColumnReference Database="[SkipPro]" Schema="[dbo]" Table="[InvoiceDetail]" Column="InvoiceId" /> <ColumnReference Database="[SkipPro]" Schema="[dbo]" Table="[InvoiceDetail]" Column="InvestigatorId" /> <ColumnReference Column="Expr1054" /> <ColumnReference Column="Expr1055" /> </OutputList> <Spool PrimaryNodeId="3" /> </RelOp> So my question is what is there that I can do to improve the speed of this thing? I already run ALTER TABLE TABLENAME NOCHECK CONSTRAINTS ALL Before the queries and then ALTER TABLE TABLENAME NOCHECK CONSTRAINTS ALL after the queries. And that didn't shave off hardly anything off of the time. Know I am running these queries in a .NET application that uses a SqlCommand object to send the query. I then tried to output the sql commands to a file and then execute it using sqlcmd, but I wasn't getting any updates on how it was doing, so I gave up on that. Any ideas or hints or help?

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  • How to isolate a single element from a scraped web page in R

    - by PaulHurleyuk
    Hello, I'm trying to do soemone a favour, and it's a tad outside my comfort zone, so I'm stuck. I want to use R to scrape this page (http://www.fifa.com/worldcup/archive/germany2006/results/matches/match=97410001/report.html ) and others, to get the goal scorers and times. So far, this is what I've got require(RCurl) require(XML) theURL <-"http://www.fifa.com/worldcup/archive/germany2006/results/matches/match=97410001/report.html" webpage <- getURL(theURL, header=FALSE, verbose=TRUE) webpagecont <- readLines(tc <- textConnection(webpage)); close(tc) pagetree <- htmlTreeParse(webpagecont, error=function(...){}, useInternalNodes = TRUE) and the pagetree object now contains a pointer to my parsed html (I think). The part I want is <div class="cont")<ul> <div class="bold medium">Goals scored</div> <li>Philipp LAHM (GER) 6', </li> <li>Paulo WANCHOPE (CRC) 12', </li> <li>Miroslav KLOSE (GER) 17', </li> <li>Miroslav KLOSE (GER) 61', </li> <li>Paulo WANCHOPE (CRC) 73', </li> <li>Torsten FRINGS (GER) 87'</li> </ul></div> but I'm now lost as to how to isolate them, and frankly xpathSApply, xpathApply confuse the beejeebies out of me !. So, does anyone know how to fomulate a command to suck out the element conmtaiend within the tags ? Thanks Paul.

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  • Dragging an UIView inside UIScrollView

    - by Sergey Mikhanov
    Hello community! I am trying to solve a basic problem with drag and drop on iPhone. Here's my setup: I have a UIScrollView which has one large content subview (I'm able to scroll and zoom it) Content subview has several small tiles as subviews that should be dragged around inside it. My UIScrollView subclass has this method: - (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event { UIView *tile = [contentView pointInsideTiles:[self convertPoint:point toView:contentView] withEvent:event]; if (tile) { return tile; } else { return [super hitTest:point withEvent:event]; } } Content subview has this method: - (UIView *)pointInsideTiles:(CGPoint)point withEvent:(UIEvent *)event { for (TileView *tile in tiles) { if ([tile pointInside:[self convertPoint:point toView:tile] withEvent:event]) return tile; } return nil; } And tile view has this method: - (void)touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event { UITouch *touch = [touches anyObject]; CGPoint location = [touch locationInView:self.superview]; self.center = location; } This works, but not fully correct: the tile sometimes "falls down" during the drag process. More precisely, it stops receiving touchesMoved: invocations, and scroll view starts scrolling instead. I noticed that this depends on the drag speed: the faster I drag, the quicker the tile "falls". Any ideas on how to keep the tile glued to the dragging finger? Thanks in advance!

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  • Is a red-black tree my ideal data structure?

    - by Hugo van der Sanden
    I have a collection of items (big rationals) that I'll be processing. In each case, processing will consist of removing the smallest item in the collection, doing some work, and then adding 0-2 new items (which will always be larger than the removed item). The collection will be initialised with one item, and work will continue until it is empty. I'm not sure what size the collection is likely to reach, but I'd expect in the range 1M-100M items. I will not need to locate any item other than the smallest. I'm currently planning to use a red-black tree, possibly tweaked to keep a pointer to the smallest item. However I've never used one before, and I'm unsure whether my pattern of use fits its characteristics well. 1) Is there a danger the pattern of deletion from the left + random insertion will affect performance, eg by requiring a significantly higher number of rotations than random deletion would? Or will delete and insert operations still be O(log n) with this pattern of use? 2) Would some other data structure give me better performance, either because of the deletion pattern or taking advantage of the fact I only ever need to find the smallest item? Update: glad I asked, the binary heap is clearly a better solution for this case, and as promised turned out to be very easy to implement. Hugo

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  • Use auto_ptr in VC6 dll cause crash

    - by Yan Cheng CHEOK
    // dll #include <memory> __declspec(dllexport) std::auto_ptr<int> get(); __declspec(dllexport) std::auto_ptr<int> get() { return std::auto_ptr<int>(new int()); } // exe #include <iostream> #include <memory> __declspec(dllimport) std::auto_ptr<int> get(); int main() { { std::auto_ptr<int> x = get(); } std::cout << "done\n"; getchar(); } The following code run perfectly OK under VC9. However, under VC6, I will experience an immediate crash with the following message. Debug Assertion Failed! Program: C:\Projects\use_dynamic_link\Debug\use_dynamic_link.exe File: dbgheap.c Line: 1044 Expression: _CrtIsValidHeapPointer(pUserData) Is it exporting auto_ptr under VC6 is not allowed? It is a known problem that exporting STL collection classes through DLL. http://stackoverflow.com/questions/2451714/access-violation-when-accessing-an-stl-object-through-a-pointer-or-reference-in-a However, I Google around and do not see anything mention for std::auto_ptr. Any workaround?

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  • is mysql index useful on column 'state' when only doing bit-operations on the column?

    - by Geert-Jan
    I have a lot of domain entities (stored in mysql) which undergo lots of different operations. Each operation is executed from a different program. I need to keep (flow)-state for these entities which I implemented in as a long field 'flowstate' used as a bitset. to query mysql for entities which have undergone a certain operation I do something like: select * from entities where state >> 7 & 1 = 1 Indicating bit 7 (cooresponding to operation 7) has run. (<-- simplified) Anyway, I really didn't pay attention to the performance implications of this setup in the beginning, and I think I'm in a bit of trouble since queries as the above run pretty slow. What I'd like to know: Does an mysql index on 'flowstate' help at all? After all it's not a single value Mysql can quickly find using a binary sort or whatever. If it doesn't, are there any other things I could do to speed things up? . Are there special 'mask-indices' for fields with use-cases as the above? TIA, Geert-jan

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  • grails scaffolding broken

    - by damian
    Grails scaffoldin does not work in my grails application. When I go from the main page to the specific controller page it output something like this: Error 500: Servlet: default URI: /myapp/myDomain/list Exception Message: Tag [sortableColumn] is missing required attribute [title] or [titleKey] at /webTestDummyDomain/list:25 Caused by: Error processing GroovyPageView: Tag [sortableColumn] is missing required attribute [title] or [titleKey] at /myDomain/list:25 Class: /myDomain/list At Line: [25] Code Snippet: Code snippet empty. If I try to create a new app scaffold works perfectly. Additional data: Application Status * App version: 0.1 * Grails version: 1.2.2 * JVM version: 1.6.0_20 * Controllers: 11 * Domains: 10 * Services: 19 * Tag Libraries: 26 Installed Plugins * i18n - 1.2.2 * filters - 1.2.2 * logging - 1.2.2 * core - 1.2.2 * tomcat - 1.2.2 * webtest - 2.0.4 * functionalTest - 1.2.7 * yui - 2.7.0.1 * rest - 0.3 * jquery - 1.4.2.1 * bubbling - 2.1.2 * urlMappings - 1.2.2 * groovyPages - 1.2.2 * servlets - 1.2.2 * dataSource - 1.2.2 * controllers - 1.2.2 * codecs - 1.2.2 * jqueryUi - 1.8-SNAPSHOT * grailsUi - 1.2-SNAPSHOT * domainClass - 1.2.2 * mimeTypes - 1.2.2 * scaffolding - 1.2.2 * converters - 1.2.2 * hibernate - 1.2.2 * validation - 1.2.2 * services - 1.2.2 Can you give me any pointer?

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  • DAL Layer : EF 4.0 or Normal Data access layer with Stored Procedure

    - by Harryboy
    Hello Experts, Application : I am working on one mid-large size application which will be used as a product, we need to decide on our DAL layer. Application UI is in Silverlight and DAL layer is going to be behind service layer. We are also moving ahead with domain model, so our DB tables and domain classes are not having same structure. So patterns like Data Mapper and Repository will definitely come into picture. I need to design DAL Layer considering below mentioned factors in priority manner Speed of Development with above average performance Maintenance Future support and stability of the technology Performance Limitation : 1) As we need to strictly go ahead with microsoft, we can not use NHibernate or any other ORM except EF 4.0 2) We can use any code generation tool (Should be Open source or very cheap) but it should only generate code in .Net, so there would not be any licensing issue on per copy basis. Questions I read so many articles about EF 4.0, on outset it looks like that it is still lacking in features from NHibernate but it is considerably better then EF 1.0 So, Do you people feel that we should go ahead with EF 4.0 or we should stick to ADO .Net and use any code geneartion tool like code smith or any other you feel best Also i need to answer questions like what time it will take to port application from EF 4.0 to ADO .Net if in future we stuck up with EF 4.0 for some features or we are having serious performance issue. In reverse case if we go ahead and choose ADO .Net then what time it will take to swith to EF 4.0 Lastly..as i was going through the article i found the code only approach (with POCO classes) seems to be best suited for our requirement as switching is really easy from one technology to other. Please share your thoughts on the same and please guide on the above questions

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  • Does height and width not apply to span?

    - by Kyle Sevenoaks
    Total noob question, but here. CSS .product__specfield_8_arrow { /*background-image:url(../../upload/orng_bg_arrow.png); background-repeat:no-repeat;*/ background-color:#fc0; width:50px !important; height:33px !important; border: 1px solid #dddddd; border-left:none; border-radius:5px; -moz-border-radius:5px; -webkit-border-radius:5px; border-bottom-left-radius:0px; border-top-left-radius:0px; -moz-border-radius-bottomleft:0px; -moz-border-radius-topleft:0px; -webkit-border-bottom-left-radius:0px; -webkit-border-top-left-radius:0px; margin:0; padding:2px; cursor:pointer; }??? HTML <span class="product__specfield_8_arrow">&nbsp;</span>? Fiddle Basically I'm trying to emulate a button, make a span (or something) look like a button next to an input field that actually doesn't need to be one because of an auto fill generator that generates errors onEnter. Thought this'd be a quick fix for now but obviously not. Thanks.

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  • Dependency between operations in scala actors

    - by paradigmatic
    I am trying to parallelise a code using scala actors. That is my first real code with actors, but I have some experience with Java Mulithreading and MPI in C. However I am completely lost. The workflow I want to realise is a circular pipeline and can be described as the following: Each worker actor has a reference to another one, thus forming a circle There is a coordinator actor which can trigger a computation by sending a StartWork() message When a worker receives a StartWork() message, it process some stuff locally and sends DoWork(...) message to its neighbour in the circle. The neighbours do some other stuff and sends in turn a DoWork(...) message to its own neighbour. This continues until the initial worker receives a DoWork() message. The coordinator can send a GetResult() message to the initial worker and wait for a reply. The point is that the coordinator should only receive a result when data is ready. How can a worker wait that the job returned to it before answering the GetResult() message ? To speed up computation, any worker can receive a StartWork() at any time. Here is my first try pseudo-implementation of the worker: class Worker( neighbor: Worker, numWorkers: Int ) { var ready = Foo() def act() { case StartWork() => { val someData = doStuff() neighbor ! DoWork( someData, numWorkers-1 ) } case DoWork( resultData, remaining ) => if( remaining == 0 ) { ready = resultData } else { val someOtherData = doOtherStuff( resultData ) neighbor ! DoWork( someOtherData, remaining-1 ) } case GetResult() => reply( ready ) } } On the coordinator side: worker ! StartWork() val result = worker !? GetResult() // should wait

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  • Self-describing file format for gigapixel images?

    - by Adam Goode
    In medical imaging, there appears to be two ways of storing huge gigapixel images: Use lots of JPEG images (either packed into files or individually) and cook up some bizarre index format to describe what goes where. Tack on some metadata in some other format. Use TIFF's tile and multi-image support to cleanly store the images as a single file, and provide downsampled versions for zooming speed. Then abuse various TIFF tags to store metadata in non-standard ways. Also, store tiles with overlapping boundaries that must be individually translated later. In both cases, the reader must understand the format well enough to understand how to draw things and read the metadata. Is there a better way to store these images? Is TIFF (or BigTIFF) still the right format for this? Does XMP solve the problem of metadata? The main issues are: Storing images in a way that allows for rapid random access (tiling) Storing downsampled images for rapid zooming (pyramid) Handling cases where tiles are overlapping or sparse (scanners often work by moving a camera over a slide in 2D and capturing only where there is something to image) Storing important metadata, including associated images like a slide's label and thumbnail Support for lossy storage What kind of (hopefully non-proprietary) formats do people use to store large aerial photographs or maps? These images have similar properties.

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  • Passing row from UIPickerView to integer CoreData attribute

    - by Gordon Fontenot
    I'm missing something here, and feeling like an idiot about it. I'm using a UIPickerView in my app, and I need to assign the row number to a 32-bit integer attribute for a Core Data object. To do this, I am using this method: -(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component { object.integerValue = row; } This is giving me a warning: warning: passing argument 1 of 'setIntegerValue:' makes pointer from integer without a cast What am I mixing up here? --EDIT 1-- Ok, so I can get rid of the errors by changing the method to do the following: NSNumber *number = [NSNumber numberWithInteger:row]; object.integerValue = rating; However, I still get a value of 0 for object.integerValue if I use NSLog to print it out. object.integerValue has a max value of 5, so I print out number instead, and then I'm getting a number above 62,000,000. Which doesn't seem right to me, since there are 5 rows. If I NSLog the row variable, I get a number between 0 and 5. So why do I end up with a completely different number after casting the number to NSNumber?

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  • NSDate out of scope

    - by therealtkd
    Having problems with out of scope for NSDate in an iphone app. I have an interface defined like this: @interface MyObject : NSoObject { NSMutableArray *array; BOOL checkThis; NSDate *nextDue; } Now in the implementation I have this: -(id) init { if( (self=[super init]) ) { checkThis = NO; array = [[NSMutableArray alloc] init]; nextDue = [[NSDate date] retain]; NSDate *testDate = [NSDate date]; } return self; } Now, if I trace through the init, before I actually assign the variables checkThis shows as boolean. array shows as pointer 0x0 because it hasn't ben assigned. But the nextDue is showing as 'out of scope'. I don't understand why this is out of scope but the other variables aren't. If I trace through the code until after the variables are assigned, array now shows as being correctly assigned but nextDue is still out of scope. Interestingly, the testDate variable is assigned just fine and the debugger shows this as a valid date. Further interesting point is if I move the mouse over the testDate variable while I am debugging, it shows as an 'NSDate *' type which I would expect since that's its definition. Yet the nextDue, which to me is defined the same way is showing as a '_NSCFDate *'. Any googling I did on the subject said that the retain is the problem, but its actually out of scope before I even try to assign the variable. However, in another class, the same definition for NSDate work ok. It shows as nil before a value is assigned to it. Arghhh

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  • Best Practice - Removing item from generic collection in C#

    - by Matt Davis
    I'm using C# in Visual Studio 2008 with .NET 3.5. I have a generic dictionary that maps types of events to a generic list of subscribers. A subscriber can be subscribed to more than one event. private static Dictionary<EventType, List<ISubscriber>> _subscriptions; To remove a subscriber from the subscription list, I can use either of these two options. Option 1: ISubscriber subscriber; // defined elsewhere foreach (EventType event in _subscriptions.Keys) { if (_subscriptions[event].Contains(subscriber)) { _subscriptions[event].Remove(subscriber); } } Option 2: ISubscriber subscriber; // defined elsewhere foreach (EventType event in _subscriptions.Keys) { _subscriptions[event].Remove(subscriber); } I have two questions. First, notice that Option 1 checks for existence before removing the item, while Option 2 uses a brute force removal since Remove() does not throw an exception. Of these two, which is the preferred, "best-practice" way to do this? Second, is there another, "cleaner," more elegant way to do this, perhaps with a lambda expression or using a LINQ extension? I'm still getting acclimated to these two features. Thanks. EDIT Just to clarify, I realize that the choice between Options 1 and 2 is a choice of speed (Option 2) versus maintainability (Option 1). In this particular case, I'm not necessarily trying to optimize the code, although that is certainly a worthy consideration. What I'm trying to understand is if there is a generally well-established practice for doing this. If not, which option would you use in your own code?

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