Search Results

Search found 42625 results on 1705 pages for 'function points'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 127/1705 | < Previous Page | 123 124 125 126 127 128 129 130 131 132 133 134  | Next Page >

  • Effective and simple matching for 2 unequal small-scale point sets

    - by Pavlo Dyban
    I need to match two sets of 3D points, however the number of points in each set can be different. It seems that most algorithms are designed to align images and trimmed to work with hundreds of thousands of points. My case are 50 to 150 points in each of the two sets. So far I have acquainted myself with Iterative Closest Point and Procrustes Matching algorithms. Implementing Procrustes algorithms seems like a total overkill for this small quantity. ICP has many implementations, but I haven't found any readily implemented version accounting for the so-called "outliers" - points without a matching pair. Besides the implementation expense, algorithms like Fractional and Sparse ICP use some statistics information to cancel points that are considered outliers. For series with 50 to 150 points statistic measures are often biased or statistic significance criteria are not met. I know of Assignment Problem in linear optimization, but it is not suitable for cases with unequal sets of points. Are there other, small-scale algorithms that solve the problem of matching 2 point sets? I am looking for algorithm names, scientific papers or C++ implementations. I need some hints to know where to start my search.

    Read the article

  • change image use javascript DOM

    - by user289346
    <html> <head> <script type="text/javascript"> var curimage = "cottage_small.jpg"; var curtext = "View large image"; function changeSrc() { if (curtext == "View large image"||curimage == "cottage_small.jpg") { document.getElementById("boldStuff").innerHTML = "View small image"; curtext="View small image"; document.getElementById("myImage")= "cottage_large.jpg"; curimage = "cottage_large.jpg"; } else { document.getElementById("boldStuff").innerHTML = "View large image"; curtext = "View large image"; document.getElementById("myImage")= "cottage_small.jpg"; curimage = "cottage_small.jpg"; } } </script> </head> <body> <!-- Your page here --> <h1> Pink Knoll Properties</h1> <h2> Single Family Homes</h2> <p> Cottage:<strong>$149,000</strong><br/> 2 bed, 1 bath, 1,189 square feet, 1.11 acres <br/><br/> <a href="#" onclick="changeSrc()"><b id="boldStuff" />View large image</a> </p> <p><img id="myImage" src="cottage_small.jpg" alt="Photo of a cottage" /></p> </body> </html> This is my coding I need to change the image and text the same time when I click it. I use LTS, it shows the line document.getElementById("myImage")= "cottage_large.jpg"; is a wrong number of arquments or invalid property assigment. Dose someone can help? Bianca

    Read the article

  • User sumbitted top 5 and sort by popularity

    - by Bundy
    Hi, Database setup (MySQL) table: top_fives id, uid, first, second, third, fourth, fifth, creation_date 1, 1, cheese, eggs, ham, bacon, ketchup, 2010-03-17 2, 2, mayonaise, cheese, ketchup, eggs, bacon, 2010-03-17 Users can submit their top 5 of a certain subject. Now I would like a summary of the top fives ordered by popularity. Each column has it's own point value. column 'first' is rewarded 5 points, 'second' four points, 'third' three points, and so on... So, in my example it should be something like this: 1 Cheese (9 points = 5 + 4 -> 1 time in 'first' column and 1 time in 'second' column) 2 Eggs (6 points) 3 Mayonaise (5 points) 4 Ketchup (4 points) 5 Bacon (3 points) 6 Ham (3 points) What would be the easiest solution (PHP) for this kind of situation? Thanks in advance

    Read the article

  • MATLAB Easter Egg Spy vs Spy

    - by Aqui1aZ3r0
    I heard that MATLAB 2009b or earlier had a fun function. When you typed spy in the console, you would get something like this: http://t2.gstatic.com/images?q=tbn:ANd9GcSHAgKz-y1HyPHcfKvBpYmZ02PWpe3ONMDat8psEr89K0VsP_ft However, now you have an image like this:http://undocumentedmatlab.com/images/spy2.png I'd like it if I could get the code of the original spy vs spy image FYI, there's a code, but has certain errors in it: c = [';@3EA4:aei7]ced.CFHE;4\T*Y,dL0,HOQQMJLJE9PX[[Q.ZF.\JTCA1dd' '-IorRPNMPIE-Y\R8[I8]SUDW2e+' '=4BGC;7imiag2IFOQLID8''XI.]K0"PD@l32UZhP//P988_WC,U+Z^Y\<2' '&lt;82BF>?8jnjbhLJGPRMJE9/YJ/L1#QMC$;;V[iv09QE99,XD.YB,[_]=3a' '9;CG?@9kokc2MKHQSOKF:0ZL0aM2$RNG%AAW\jw9E.FEE-_G8aG.d]_W5+' '?:CDH@A:lpld3NLIRTPLG=1[M1bN3%SOH4BBX]kx:J9LLL8H9bJ/+d_dX6,' '@;DEIAB;mqmePOMJSUQMJ2\N2cO4&TPP@HCY^lyDKEMMN9+I@+S8,+deY7^' '8@EFJBC<4rnfQPNPTVRNKB3]O3dP5''UQQCIDZ_mzEPFNNOE,RA,T9/,++\8_' '9A2G3CD=544gRQPQUWUOLE4^P4"Q6(VRRIJE[n{KQKOOPK-SE.W:F/,,]Z+' ':BDH4DE>655hSRQRVXVPMF5_Q5#R>)eSSJKF\ao0L.L-WUL.VF8XCH001_[,' ';3EI<eo ?766iTSRSWYWQNG6$R6''S?*fTTlLQ]bp1M/P.XVP8[H9]DIDA=]' '?4D3=FP@877jUTSTXZXROK7%S7(TF+gUUmMR^cq:N9Q8YZQ9_IcIJEBd_^' '@5E@GQA98b3VUTUY*YSPL8&T)UI,hVhnNS_dr;PE.9Z[RCaR?+JTFC?e+' '79FA?HRB:9c4WVUVZ+ZWQM=,WG*VJ-"gi4OTes-XH+bK.#hj@PUvftDRMEF,]UH,UB.TYVWX,e\' '9;ECAKTY< ;eWYXWX\:)YSOE.YI,cL/$ikCqV1guE/PFL-^XI-YG/WZWXY1+]' ':AFDBLUZ=jgY[ZYZ-<7[XQG0[K.eN1&"$K2u:iyO9.PN9-_K8aJ9_]]82[' '?CEFDNW\?khZ[Z[==8\YRH1\M/!O2''#%m31Bw0PE/QXE8+R9bS;da^]93\' '@2FGEOX]ali[][9(ZSL2]N0"P3($&n;2Cx1QN9--L9,SA+T< +d_:4,' 'A3GHFPY^bmj\^]\]??:)[TM3^O1%Q4)%''oA:D0:0OE.8ME-TE,XB,+da;5[' '643IGQZ_cnk]_^]^@@;5\UN4_P2&R6*&(3B;E1<1PN99NL8WF.^C/,a+bY6,' '7:F3HR[dol^_^AA<6]VO5Q3''S>+'');CBF:=:QOEEOO9_G8aH6/d,cZ[Y' '8;G4IS\aep4_a-BD=7''XP6aR4(T?,(5@DCHCC;RPFLPPDH9bJ70+0d\\Z' '9BH>JT^bf45ba.CE@8(YQ7#S5)UD-)?AEDIDDD/QKMVQJ+S?cSDF,1e]a,' ':C3?K4_cg5[acbaADFA92ZR8$T6*VE.*@JFEJEEE0.NNWTK,U@+TEG0?+_bX' ';2D@L9dh6\bdcbBEGD:3[S=)U7+cK/+CKGFLIKI9/OWZUL-VA,WIHB@,`cY']; i = double(c(:)-32); j = cumsum(diff([0; i])< =0) + 1; S = sparse(i,j,1)'; spy(S)

    Read the article

  • Separating arguments to a function, in locales with comma as decimal marker

    - by Chris Pousset
    In locales, e.g. French, with comma as decimal indicator (where "5,2" means five and two-tenths), how do users separate function arguments from each other? For example, in many programming/scripting languages, I could specify MAX(1.5, X) in a EN-US locale. How do you avoid the ambiguity between the comma as decimal indicator, and as argument separator? In particular, I'm interested in how software that's perceived as user-friendly in the foreign locale does it. Obviously, it's a no-brainer to say, "thou shalt use decimal POINTs", but that's not particularly "friendly".

    Read the article

  • How do I set the current point in a CG graphics context?

    - by Joe
    When running the code below in the iphone simulator I get the error : CGContextClosePath: no current point. Why is the current point not being set? Or is the context not set to the correct state? CGContextBeginPath(ctx); CGMutablePathRef pathHolder; pathHolder = CGPathCreateMutable(); //move to point for the initial point NSLog(@"Drawing a state point %f, %f", [[holder.points objectAtIndex:0] floatValue], [[holder.points objectAtIndex:1] floatValue]); CGPathMoveToPoint(pathHolder, NULL, [[holder.points objectAtIndex:0] floatValue], [[holder.points objectAtIndex:1] floatValue]); for(int x = 2; x < [holder.points count] - 1; x += 2) { NSLog(@"Drawing a state point %f, %f", [[holder.points objectAtIndex:x] floatValue], [[holder.points objectAtIndex:(x+1)] floatValue]); CGPathAddLineToPoint(pathHolder, NULL, [[holder.points objectAtIndex:x] floatValue], [[holder.points objectAtIndex:(x+1)] floatValue]); } CGContextClosePath(ctx); CGContextFillPath(ctx);

    Read the article

  • Jquery addClass on radio box checked.

    - by Zoltan Repas
    I checked all the topics, but i simply don't know why my script does not work :( <script type="text/javascript" src="http://code.jquery.com/jquery-1.4.2.min.js"></script> <script type="text/javascript"> $('#pic').click(function() { $(this).parents("li").find(".green").removeClass("green"); if($(this).is(':checked')) { $(this).parents("ul").find("li").addClass('green'); } }); </script> etc... <ul> <li><input type="radio" name="pic" value="asd"/>asd</li> <li><input type="radio" name="pic" value="b"/>asd</li> <li><input type="radio" name="pic" value="ba"/>asd</li> <li><input type="radio" name="pic" value="bs"/>asd</li> <li><input type="radio" name="pic" value="bc"/>asd</li> </ul> Please help me!

    Read the article

  • Initializing objects on the fly

    - by pocoa
    I have a vector called players and a class called Player. And what I'm trying to do is to write: players.push_back(Player(name, Weapon(bullets))); So I want to be able to create players in a loop. But I see an error message says "no matching function for call Player::Player..." Then I've changed that to: Weapon w(bullets); Player p(name, w); players.push_back(p); Here is my Player definition: class Player { public: Player(string &name, Weapon &weapon); private string name; Weapon weapon; } I'm just trying to learn what is the difference between these definitions. And is this the right way to pass an object to an object constructor. Note: These are not my actual class definitions. I'm just trying to learn something about object oriented programming in C++ with coding it. I mean I know that Weapon should be initialized in Player :)

    Read the article

  • PHP Replace chars by functions

    - by user1860570
    I try change characters by functions <?php $string = "Hi everybody people [gal~images/articles~100~100~4] here other imagen [gal~images/products~100~100~3]"; $regex = "/\[(.*?)\]/"; preg_match_all($regex, $string, $matches); for($i=0; $i<count($matches[1]);$i++) { $match = $matches[1][$i]; $array = explode('~', $match); //$newValuet="gal("".$array[1]."","".$array[2]."","".$array[3]."","".$array[4]."")"; $newValue="gal(".$array[1].",".$array[2].",".$array[3].",".$array[4].")"; $string = str_replace($matches[0][$i],$newValue,$string); } echo $string; ?> The problem here : $newValue="gal(".$array[1].",".$array[2].",".$array[3].",".$array[4].")"; $string = str_replace($matches[0][$i],$newValue,$string); Function no give the right results i try differents methods but continue the problems , please i see all functions but no get this works if you can answer please put me some modification of this code for i can understand , thank´s a lot for all help

    Read the article

  • What is different about C++ math.h abs() compared to my abs()

    - by moka
    I am currently writing some glsl like vector math classes in c++, and I just implemented an abs() function like this: template<class T> static inline T abs(T _a) { return _a < 0 ? -_a : _a; } I compared its speed to the default c++ abs from math.h like this: clock_t begin = clock(); for(int i=0; i<10000000; ++i) { float a = abs(-1.25); }; clock_t end = clock(); unsigned long time1 = (unsigned long)((float)(end-begin) / ((float)CLOCKS_PER_SEC/1000.0)); begin = clock(); for(int i=0; i<10000000; ++i) { float a = myMath::abs(-1.25); }; end = clock(); unsigned long time2 = (unsigned long)((float)(end-begin) / ((float)CLOCKS_PER_SEC/1000.0)); std::cout<<time1<<std::endl; std::cout<<time2<<std::endl; Now the default abs takes about 25ms while mine takes 60. I guess there is some low level optimisation going on. Does anybody know how math.h abs works internally? The performance difference is nothing dramatic, but I am just curious!

    Read the article

  • In Ruby, why does a method invocation not be able to be treated as a unit when "do" and "end" is use

    - by Jian Lin
    The following question is related to http://stackoverflow.com/questions/2127836/ruby-print-inject-do-syntax The question is, can we insist on using DO and END and make it work with puts or p? This works: a = [1,2,3,4] b = a.inject do |sum, x| sum + x end puts b # prints out 10 so, is it correct to say, inject is a class method of the Array class, which takes a block of code, and then returns a number. If so, then it should be no different from calling a function and getting back a return value: b = foo(3) puts b or b = circle.getRadius() puts b In the above two cases, we can directly say puts foo(3) puts circle.getRadius() so, there is no way to make it work directly by using the following 2 ways: a = [1,2,3,4] puts a.inject do |sum, x| sum + x end but it gives ch01q2.rb:7:in `inject': no block given (LocalJumpError) from ch01q2.rb:4:in `each' from ch01q2.rb:4:in `inject' from ch01q2.rb:4 grouping the method call using ( ) doesn't work either: a = [1,2,3,4] puts (a.inject do |sum, x| sum + x end) and this gives: ch01q3.rb:4: syntax error, unexpected kDO_BLOCK, expecting ')' puts (a.inject do |sum, x| ^ ch01q3.rb:4: syntax error, unexpected '|', expecting '=' puts (a.inject do |sum, x| ^ ch01q3.rb:6: syntax error, unexpected kEND, expecting $end end) ^ finally, the following version works: a = [1,2,3,4] puts a.inject { |sum, x| sum + x } but why doesn't the grouping of the method invocation using ( ) work? What if a programmer insists that he uses do and end, can it be made to work directly with p or puts, without an extra temporary variable?

    Read the article

  • In Ruby, why is a method invocation not be able to be treated as a unit when "do" and "end" is used?

    - by Jian Lin
    The following question is related to the question "Ruby Print Inject Do Syntax". My question is, can we insist on using do and end and make it work with puts or p? This works: a = [1,2,3,4] b = a.inject do |sum, x| sum + x end puts b # prints out 10 so, is it correct to say, inject is a class method of the Array class, which takes a block of code, and then returns a number. If so, then it should be no different from calling a function and getting back a return value: b = foo(3) puts b or b = circle.getRadius() puts b In the above two cases, we can directly say puts foo(3) puts circle.getRadius() so, there is no way to make it work directly by using the following 2 ways: a = [1,2,3,4] puts a.inject do |sum, x| sum + x end but it gives ch01q2.rb:7:in `inject': no block given (LocalJumpError) from ch01q2.rb:4:in `each' from ch01q2.rb:4:in `inject' from ch01q2.rb:4 grouping the method call using ( ) doesn't work either: a = [1,2,3,4] puts (a.inject do |sum, x| sum + x end) and this gives: ch01q3.rb:4: syntax error, unexpected kDO_BLOCK, expecting ')' puts (a.inject do |sum, x| ^ ch01q3.rb:4: syntax error, unexpected '|', expecting '=' puts (a.inject do |sum, x| ^ ch01q3.rb:6: syntax error, unexpected kEND, expecting $end end) ^ finally, the following version works: a = [1,2,3,4] puts a.inject { |sum, x| sum + x } but why doesn't the grouping of the method invocation using ( ) work in the earlier example? What if a programmer insist that he uses do and end, can it be made to work?

    Read the article

  • Wordpress inserting comments via wp_insert_comment()

    - by Cyber Junkie
    Hello all happy holidays! :) I'm trying to insert comments in my wordpress blog via the wp_insert_comment() function. It's for a plugin I'm trying to make. I have this code in my header for testing. It works every time I refresh the page. $agent = $_SERVER['HTTP_USER_AGENT']; $data = array( 'comment_post_ID' => 256, 'comment_author' => 'Dave', 'comment_author_email' => '[email protected]', 'comment_author_url' => 'http://www.someiste.com', 'comment_content' => 'Lorem ipsum dolor sit amet...', 'comment_author_IP' => '127.3.1.1', 'comment_agent' => $agent, 'comment_date' => date('Y-m-d H:i:s'), 'comment_date_gmt' => date('Y-m-d H:i:s'), 'comment_approved' => 1, ); $comment_id = wp_insert_comment($data); It successfully inserts comments into the database. The problem: Comments don't show via the Disqus comment system. I compared table rows and I noticed that user_agent differs. Normal comments use for example, Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv... and Disqus comments use Disqus/1.1(2.61):119598902 numbers are different for each comment. Does anyone know how to insert comments with wp_insert_comment() when Disqus is enabled?

    Read the article

  • SQL wont work? It doesn't come up with errors either

    - by Stefan
    Hey there, I have php function which checks to see if variables are set and then adds them onto my sql query. However I am don't seem to be getting any results back!? $where_array = array(); if (array_key_exists("location", $_GET)) { $location = addslashes($_GET['location']); $where_array[] = "`mainID` = '".$location."'"; } if (array_key_exists("gender", $_GET)) { $gender = addslashes($_GET["gender"]); $where_array[] = "`gender` = '".$gender."'"; } if (array_key_exists("hair", $_GET)) { $hair = addslashes($_GET["hair"]); $where_array[] = "`hair` = '".$hair."'"; } if (array_key_exists("area", $_GET)) { $area = addslashes($_GET["area"]); $where_array[] = "`locationID` = '".$area."'"; } $where_expr = ''; if ($where_array) { $where_expr = "WHERE " . implode(" AND ", $where_array); } $sql = "SELECT `postID` FROM `posts` ". $where_expr; $dbi = new db(); $result = $dbi->query($sql); $r = mysql_fetch_row($result); I'm trying to call the data after in a list like so: $dbi = new db(); $offset = ($currentpage - 1) * $rowsperpage; // get the info from the db $sql .= " ORDER BY `time` DESC LIMIT $offset, $rowsperpage"; $result = $dbi->query($sql); // while there are rows to be fetched... while ($row = mysql_fetch_object($result)){ // echo data echo $row['text']; } // end while Anyone got any ideas why I am not retrieving any data? -Stefan

    Read the article

  • I don't like Python functions that take two or more iterables. Is it a good idea?

    - by Xavier Ho
    This question came from looking at this question on Stackoverflow. def fringe8((px, py), (x1, y1, x2, y2)): Personally, it's been one of my pet peeves to see a function that takes two arguments with fixed-number iterables (like a tuple) or two or more dictionaries (Like in the Shotgun API). It's just hard to use, because of all the verbosity and double-bracketed enclosures. Wouldn't this be better: >>> class Point(object): ... def __init__(self, x, y): ... self.x = x ... self.y = y ... >>> class Rect(object): ... def __init__(self, x1, y1, x2, y2): ... self.x1 = x1 ... self.y1 = y1 ... self.x2 = x2 ... self.y2 = y2 ... >>> def fringe8(point, rect): ... # ... ... >>> >>> point = Point(2, 2) >>> rect = Rect(1, 1, 3, 3) >>> >>> fringe8(point, rect) Is there a situation where taking two or more iterable arguments is justified? Obviously the standard itertools Python library needs that, but I can't see it being pretty in maintainable, flexible code design.

    Read the article

  • How to change the meaning of pointer access operator

    - by kumar_m_kiran
    Hi All, This may be very obvious question, pardon me if so. I have below code snippet out of my project, #include <stdio.h> class X { public: int i; X() : i(0) {}; }; int main(int argc,char *arv[]) { X *ptr = new X[10]; unsigned index = 5; cout<<ptr[index].i<<endl; return 0; } Question Can I change the meaning of the ptr[index] ? Because I need to return the value of ptr[a[index]] where a is an array for subindexing. I do not want to modify existing source code. Any new function added which can change the behavior is needed. Since the access to index operator is in too many places (536 to be precise) in my code, and has complex formulas inside the index subscript operator, I am not inclined to change the code in many locations. PS : 1. I tried operator overload and came to conclusion that it is not possible. 2. Also p[i] will be transformed into *(p+i). I cannot redefine the basic operator '+'. So just want to reconfirm my understanding and if there are any possible short-cuts to achieve. Else I need fix it by royal method of changing every line of code :) .

    Read the article

  • How to open links in new window ONLY IF the check box is checked

    - by Travis
    Here is what i have so far. I have it so they open in new windows, but i want it only if the check box is checked... <!DOCTYPE html> <html> <head> <script> function new() { if ( document.getElementById('checkbox').checked ) window.open( 'y', 'n', 't', 'New Window' ); } else { break; } var OpenNew = document.getElementById('opennew'); OpenNew.addEventListener('click', OpenWin, false ); </script> </head> <body> <p> <form name="test"> <p>Open link in a new window &nbsp; <input type="checkbox" id="checkbox" name="check" /></p> </form> </p> <p> <h2>My favorite Websites to visit</h2> <a href="http://www.youtube.com" target="new" id="y">Youtube</a><br /> <a href="http://www.newegg.com" target="new" id="n">Newegg</a><br /> <a href="http://www.twitch.tv" target="new" id="t">Twitch.tv</a><br /> </p> </body> </html> I am unsure how to actually do the if statement if it is checked then open. It does currently open in a new tab.. i just need it to be only when its checked. Any help with this will be greatly appreciated! Thanks!

    Read the article

  • Calling Base Class Functions with Inherited Type

    - by Kein Mitleid
    I can't describe exactly what I want to say but I want to use base class functions with an inherited type. Like I want to declare "Coord3D operator + (Coord3D);" in one class, but if I use it with Vector3D operands, I want it to return Vector3D type instead of Coord3D. With this line of code below, I add two Vector3D's and get a Coord3D in return, as told to me by the typeid().name() function. How do I reorganize my classes so that I get a Vector3D on return? #include <iostream> #include <typeinfo> using namespace std; class Coord3D { public: float x, y, z; Coord3D (float = 0.0f, float = 0.0f, float = 0.0f); Coord3D operator + (Coord3D &); }; Coord3D::Coord3D (float a, float b, float c) { x = a; y = b; z = c; } Coord3D Coord3D::operator+ (Coord3D &param) { Coord3D temp; temp.x = x + param.x; temp.y = y + param.y; temp.z = z + param.z; return temp; } class Vector3D: public Coord3D { public: Vector3D (float a = 0.0f, float b = 0.0f, float c = 0.0f) : Coord3D (a, b, c) {}; }; int main () { Vector3D a (3, 4, 5); Vector3D b (6, 7, 8); cout << typeid(a + b).name(); return 0; }

    Read the article

  • Haskel dot (.) and dollar ($) composition: correct use.

    - by Robert Massaioli
    I have been reading Real World Haskell and I am nearing the end but a matter of style has been niggling at me to do with the (.) and ($) operators. When you write a function that is a composition of other functions you write it like: f = g . h But when you apply something to the end of those functions I write it like this: k = a $ b $ c $ value But the book would write it like this: k = a . b . c $ value Now to me they look functionally equivalent, they do the exact same thing in my eyes. However, the more I look, the more I see people writing their functions in the manner that the book does: compose with (.) first and then only at the end use ($) to append a value to evaluate the lot (nobody does it with many dollar compositions). Is there a reason for using the books way that is much better than using all ($) symbols? Or is there some best practice here that I am not getting? Or is it superfluous and I shouldn't be worrying about it at all? Thanks.

    Read the article

  • How to pass data to a C++0x lambda function that will run in a different thread?

    - by Dimitri C.
    In our company we've written a library function to call a function asynchronously in a separate thread. It works using a combination of inheritance and template magic. The client code looks as follows: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, &DemoThread::SomeFunction, stringToPassByValue); Since the introduction of lambda functions I'd like to use it in combination with lambda functions. I'd like to write the following client code: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, [=]() { const std::string someCopy = stringToPassByValue; }); Now, with the Visual C++ 2010 this code doesn't work. What happens is that the stringToPassByValue is not copied. Instead the "capture by value" feature passes the data by reference. The result is that if the function is executed after stringToPassByValue has gone out of scope, the application crashes as its destructor is called already. So I wonder: is it possible to pass data to a lambda function as a copy? Note: One possible solution would be to modify our framework to pass the data in the lambda parameter declaration list, as follows: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, [=](const std::string stringPassedByValue) { const std::string someCopy = stringPassedByValue; } , stringToPassByValue); However, this solution is so verbose that our original function pointer solution is both shorter and easier to read. Update: The full implementation of AsyncCall is too big to post here. In short, what happens is that the AsyncCall template function instantiates a template class holding the lambda function. This class is derived from a base class that contains a virtual Execute() function, and upon an AsyncCall() call, the function call class is put on a call queue. A different thread then executes the queued calls by calling the virtual Execute() function, which is polymorphically dispatched to the template class which then executes the lambda function.

    Read the article

  • scheme basic loop

    - by utku
    I'm trying to write a scheme func that behaves in a way similar to a loop. (loop min max func) This loop should perform the func between the range min and max (integers) -- one of an example like this (loop 3 6 (lambda (x) (display (* x x)) (newline))) 9 16 25 36 and I define the function as ( define ( loop min max fn) (cond ((>= max min) ( ( fn min ) ( loop (+ min 1 ) max fn) ) ) ) ) when I run the code I get the result then an error occur. I couldn't handle this error. (loop 3 6 (lambda (x) (display(* x x))(newline))) 9 16 25 36 Backtrace: In standard input: 41: 0* [loop 3 6 #] In utku1.scheme: 9: 1 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 2 [# ... 10: 3* [loop 4 6 #] 9: 4 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 5 [# ... 10: 6* [loop 5 6 #] 9: 7 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 8 [# ... 10: 9* [loop 6 6 #] 9: 10 (cond ((= max min) ((fn min) (loop # max fn)))) 10: 11 [# #] utku1.scheme:10:31: In expression ((fn min) (loop # max ...)): utku1.scheme:10:31: Wrong type to apply: #<unspecified> ABORT: (misc-error)

    Read the article

  • using time() to measure how long a function takes

    - by hap497
    Hi, I am trying to use time() to measure various points of my program. http://www.cplusplus.com/reference/clibrary/ctime/time/ What I don't understand is why the values in the before and after are Different? I understanding this is not the best way to profile my program, I just want to see how long does something take. printf ("**MyProgram::before time= %ld\n", time(NULL)); doSomthing(); doSomthingLong(); printf ("**MyProgram::after time= %ld\n", time(NULL)); Thank you.

    Read the article

  • Strange overloading rules in C++

    - by bucels
    I'm trying to compile this code with GCC 4.5.0: #include <algorithm> #include <vector> template <typename T> void sort(T, T) {} int main() { std::vector<int> v; sort(v.begin(), v.end()); } But it doesn't seem to work: $ g++ -c nm.cpp nm.cpp: In function ‘int main()’: nm.cpp:9:28: error: call of overloaded ‘sort(std::vector<int>::iterator, std::vector<int>::iterator)’ is ambiguous nm.cpp:4:28: note: candidates are: void sort(T, T) [with T = __gnu_cxx::__normal_iterator<int*, std::vector<int> >] /usr/lib/gcc/i686-pc-linux-gnu/4.5.0/../../../../include/c++/4.5.0/bits/stl_algo.h:5199:69: note: void std::sort(_RAIter, _RAIter) [with _RAIter = __gnu_cxx::__normal_iterator<int*, std::vector<int> >] Comeau compiles this code without errors. (4.3.10.1 Beta2, strict C++03, no C++0x) Is this valid C++?

    Read the article

  • In Ruby, why is a method invocation not able to be treated as a unit when "do" and "end" is used?

    - by Jian Lin
    The following question is related to the question "Ruby Print Inject Do Syntax". My question is, can we insist on using do and end and make it work with puts or p? This works: a = [1,2,3,4] b = a.inject do |sum, x| sum + x end puts b # prints out 10 so, is it correct to say, inject is an instance method of the Array object, and this instance method takes a block of code, and then returns a number. If so, then it should be no different from calling a function or method and getting back a return value: b = foo(3) puts b or b = circle.getRadius() puts b In the above two cases, we can directly say puts foo(3) puts circle.getRadius() so, there is no way to make it work directly by using the following 2 ways: a = [1,2,3,4] puts a.inject do |sum, x| sum + x end but it gives ch01q2.rb:7:in `inject': no block given (LocalJumpError) from ch01q2.rb:4:in `each' from ch01q2.rb:4:in `inject' from ch01q2.rb:4 grouping the method call using ( ) doesn't work either: a = [1,2,3,4] puts (a.inject do |sum, x| sum + x end) and this gives: ch01q3.rb:4: syntax error, unexpected kDO_BLOCK, expecting ')' puts (a.inject do |sum, x| ^ ch01q3.rb:4: syntax error, unexpected '|', expecting '=' puts (a.inject do |sum, x| ^ ch01q3.rb:6: syntax error, unexpected kEND, expecting $end end) ^ finally, the following version works: a = [1,2,3,4] puts a.inject { |sum, x| sum + x } but why doesn't the grouping of the method invocation using ( ) work in the earlier example? What if a programmer insist that he uses do and end, can it be made to work?

    Read the article

  • How to call shared_ptr<boost::signal> from a vector in a loop?

    - by BTR
    I've got a working callback system that uses boost::signal. I'm extending it into a more flexible and efficient callback manager which uses a vector of shared_ptr's to my signals. I've been able to successfully create and add callbacks to the list, but I'm unclear as to how to actually execute the signals. ... // Signal aliases typedef boost::signal<void (float *, int32_t)> Callback; typedef std::shared_ptr<Callback> CallbackRef; // The callback list std::vector<CallbackRef> mCallbacks; // Adds a callback to the list template<typename T> void addCallback(void (T::* callbackFunction)(float * data, int32_t size), T * callbackObject) { CallbackRef mCallback = CallbackRef(new Callback()); mCallback->connect(boost::function<void (float *, int32_t)>(boost::bind(callbackFunction, callbackObject, _1, _2))); mCallbacks.push_back(mCallback); } // Pass the float array and its size to the callbacks void execute(float * data, int32_t size) { // Iterate through the callback list for (vector<CallbackRef>::iterator i = mCallbacks.begin(); i != mCallbacks.end(); ++i) { // What do I do here? // (* i)(data, size); // <-- Dereferencing doesn't work } } ... All of this code works. I'm just not sure how to run the call from within a shared_ptr from with a vector. Any help would be neat-o. Thanks, in advance.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 123 124 125 126 127 128 129 130 131 132 133 134  | Next Page >