Search Results

Search found 17924 results on 717 pages for 'z order'.

Page 489/717 | < Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >

  • Improve C function performance with cache locality?

    - by Christoper Hans
    I have to find a diagonal difference in a matrix represented as 2d array and the function prototype is int diagonal_diff(int x[512][512]) I have to use a 2d array, and the data is 512x512. This is tested on a SPARC machine: my current timing is 6ms but I need to be under 2ms. Sample data: [3][4][5][9] [2][8][9][4] [6][9][7][3] [5][8][8][2] The difference is: |4-2| + |5-6| + |9-5| + |9-9| + |4-8| + |3-8| = 2 + 1 + 4 + 0 + 4 + 5 = 16 In order to do that, I use the following algorithm: int i,j,result=0; for(i=0; i<4; i++) for(j=0; j<4; j++) result+=abs(array[i][j]-[j][i]); return result; But this algorithm keeps accessing the column, row, column, row, etc which make inefficient use of cache. Is there a way to improve my function?

    Read the article

  • Declaring two classes that contain instance variables of each others' types.

    - by Benji XVI
    Let’s say you wish to have two classes like so, each declaring an instance variable that is of the other’s class. @interface A : NSObject { B *something; } @end @interface B : NSObject { A *something; } @end It seems to be impossible to declare these classes with these instance variables. In order for A to include an IV of class B, B must already be compiled, and so its @interface must come before A’s. But A’s must be put before B’s for the same reason. Putting the two class declarations in separate files, and #import-ing each other’s .h doesn’t work either, for obvious reasons. So, what is the solution? Or is this either (1) impossible or (2) indicative of a bad design anyway?

    Read the article

  • Is it a good idea to include a large text variable in compiled code?

    - by gladman
    I am writing a program that produces a formatted file for the user, but it's not only producing the formatted file, it does more. I want to distribute a single binary to the end user and when the user runs the program, it will generate the xml file for the user with appropriate data. In order to achieve this, I want to give the file contents to a char array variable that is compiled in code. When the user runs the program, I will write out the char file to generate an xml file for the user. char* buffers = "a xml format file contents, \ this represent many block text \ from a file,..."; I have two questions. Q1. Do you have any other ideas for how to compile my file contents into binary, i.e, distribute as one binary file. Q2. Is this even a good idea as I described above?

    Read the article

  • Where can I find a compact programming keyboard with logical key placement?

    - by Lefler
    I recently, at the order of my chiropractor, bought a laptop stand to elevate my screen. A result of this is that I need a standalone keyboard. Normal keyboards have numeric keypads on the right side, which moves my mouse further to the right... not an optimal position chiropractically speaking. I don't use the numeric keypad, but all the compact keyboards I can find use some random placement algorithm on the arrow, page up/down, and most importantly -- the insert,delete,home and end keys. Those misplaced keys are crippling my code entry. Does anyone know of a keyboard that is minus the keypad, but places those VERY IMPORTANT keys in a more standard position?

    Read the article

  • "Volkswagen Passat" Navigation

    - by joe_midi
    http://web.vw.com/all-new-passat-experience/ The navigation on this .swf is very impressive, and I was wondering how I would go about replicating it. The way each of the sections Design / Technology / Safety / Performance I want to know how each section can expand and still fit together. I've started with MOUSE_OVER events, but I'm not entirely sure how to order them so each section is the right size for every mouse over Event. This is the code I have for each "Section", I have created a movie clip with a Mask that expands on mouse over and brings the selected clip to the highest depth. this.firstButton01.addEventListener(MouseEvent.MOUSE_OVER, firstButton01OVER) function firstButton01OVER(e:Event):void { this.firstButton01.gotoAndPlay(2); this.setChildIndex(firstButton01,this.numChildren-1); }

    Read the article

  • How does the #! work?

    - by mocybin
    In a script you must include a #! on the first line followed by the path to the program that will execute the script (e.g.: sh, perl). As far as I know though, the # character denotes the start of a comment and that line is supposed to be ignored by the program executing the script. It would seem though, that this first line is at some point read by something in order for the script to be executed by the proper program. Could somebody please shed more light on the workings of the #! ? Edit: I'm really curious about this, so the more in-depth the answer the better.

    Read the article

  • Search box inside a div. Django

    - by Juliette Dupuis
    In my django app I display a list of elements (friends name) thanks to a loop: <div> {% for friend in group %} <p>{{ friend.name }} <p> {% endfor %} </div> I would like to create a search box on the top of my list in order to be able to find only the friends the user wants. I would like the search bar does not need to click to send the request (an example is the Airtime searchbox on top of the facebook friends list). I have absolutely no idea on how to do that, and I'm looking for hints or tips to start. Thank you very much for your help.

    Read the article

  • Help needed in pivoting (SQL Server 2005)

    - by Newbie
    I have a table like ID Grps Vals --- ---- ----- 1 1 1 1 1 3 1 1 45 1 2 23 1 2 34 1 2 66 1 3 10 1 3 17 1 3 77 2 1 144 2 1 344 2 1 555 2 2 11 2 2 22 2 2 33 2 3 55 2 3 67 2 3 77 The desired output being ID Record1 Record2 Record3 --- ------- ------- ------- 1 1 23 10 1 3 34 17 1 45 66 77 2 144 11 55 2 344 22 67 2 555 33 77 I have tried(using while loop) but the program is running slow. I have been asked to do so by using SET based approach. My approach so far is SELECT ID,[1] AS [Record1], [2] AS [Record2], [3] as [Record3] FROM ( Select Row_Number() Over(Partition By ID Order By Vals) records ,* From myTable)x PIVOT (MAX(vals) FOR Grps IN ([1],[2],[3])) p But it is not working. Can any one please help to solve this.(SQL SERVER 2005)

    Read the article

  • The right way to implement communication between java objects

    - by imoschak
    I'm working on an academic project which simulates a rather large queuing procedure in java. The core of the simulator rests within one package where there exist 8 classes each one implementing a single concept. Every class in the project follows SRP. These classes encapsulate the behavior of the simulator and inter-connect every other class in the project. The problem that I has arisen is that most of these 8 classes are, as is logical i think, tightly coupled and each one has to have working knowledge of every other class in this package in order to be able to call methods from it when needed. The application needs only one instance of each class so it might be better to create static fields for each class in a new class and use that to make calls -instead of preserving a reference in each class for every other class in the package (which I'm certain that is incorrect)-, but is this considered a correct design solution? or is there a design pattern maybe that better suits my needs?

    Read the article

  • Updating cached counts in MySQL

    - by phleet
    In order to fix a bug, I have to iterate over all the rows in a table, updating a cached count of children to what its real value should be. The structure of the things in the table form a tree. In rails, the following does what I want: Thing.all.each do |th| Thing.connection.update( " UPDATE #{Thing.quoted_table_name} SET children_count = #{th.children.count} WHERE id = #{th.id} " ) end Is there any way of doing this in a single MySQL query? Alternatively, is there any way of doing this in multiple queries, but in pure MySQL? I want something like UPDATE table_name SET children_count = ( SELECT COUNT(*) FROM table_name AS tbl WHERE tbl.parent_id = table_name.id ) except the above doesn't work (I understand why it doesn't).

    Read the article

  • C# Generics Multiple Inheritance Problem

    - by Ciemnl
    Can any one help me with this syntax issue with C#? I have no idea how to do it. class SomeClass<T> : SomeOtherClass<T> where T : ISomeInterface , IAnotherInterface { ... } I want SomeClass to inherit from SomeOtherClass and IAnotherInterface and for T to inherit ISomeInterface only It seems the problem is that the where keyword screws everything up so that the compiler thinks both ISomeInterface and IAnotherInterface should both be inherited by T. This problem is very annoying and I think the solution is some kind of parenthesis but I have tried and failed finding one that works. Also, switching around the order of the two items inherited from SomeClass does not work because the class inherited always has to come before any interfaces. I couldn't find any solutions on the MSDN C# generics pages and I can't beleive I'm the first person to have this problem. Thanks, any help is much appreciated!

    Read the article

  • How to call 3 threads sequentially many times?

    - by Hello
    How to call 3 threads sequentially many times? For example: In iteration 1, execution order should be "Thread0-thread1-thread2" then in iteration 2 should be same i.e "Thread0 - thread1-thread2" and so on. The sample code is just executing 3 threads only once. It is not going to 2nd iteration. Thread0 = CreateThread( NULL,0,ThreadProc0, NULL, CREATE_SUSPENDED, &ThreadID); Thread1 = CreateThread( NULL,0,ThreadProc1, NULL, CREATE_SUSPENDED, &ThreadID); Thread2 = CreateThread( NULL,0,ThreadProc2, NULL, CREATE_SUSPENDED, &ThreadID); for(i=0;i<iterations;i++) //Iterations in calling threads { ResumeThread(Thread0); WaitForSingleObject(Thread0, INFINITE); ResumeThread(Thread1); WaitForSingleObject(Thread1, INFINITE); ResumeThread(Thread2); WaitForSingleObject(Thread2, INFINITE); } // Close thread and semaphore handles

    Read the article

  • How to roeder the rows of one matrix with respect to the other matrix?

    - by user2806363
    I have two big matrices A and B with diffrent dimensions.I want to order the rows of matrix B with respect to rows of the matrix A. and add the rows with values 0 to matrix B, if that row is not exist in B but in A Here is the reproduceable example and expected output: A<-matrix(c(1:40), ncol=8) rownames(A)<-c("B", "A", "C", "D", "E") > A [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] B 1 6 11 16 21 26 31 36 A 2 7 12 17 22 27 32 37 C 3 8 13 18 23 28 33 38 D 4 9 14 19 24 29 34 39 E 5 10 15 20 25 30 35 40 > B<-matrix(c(100:108),ncol=3) rownames(B)<-c("A", "E", "C") > B [,1] [,2] [,3] A 100 103 106 E 101 104 107 C 102 105 108 Here is the Expected output : >B [,1] [,2] [,3] B 0 0 0 A 100 103 106 C 102 105 108 D 0 0 0 E 101 104 107 > Would someone help me to implement this in R ?

    Read the article

  • endpoints (bug?) behavior in xts

    - by Alex
    If I try to get endpoints for every year, for example, and do the following: xts.data <- xts(1:10000, order.by=seq(from=as.Date("1970-01-01"), by=1, len=10000)) z <- endpoints(xts.data, on="months", k=12) The return value for this is: > z [1] 0 10000 Same with numbers higher than 12. Why would xts simply not return indices of every year or 13th month starting from the beginning. Is it limited by the number of periods in a year? That is if i did: z <- endpoints(xts.data, on="weeks", k=54) This seems to work fine.

    Read the article

  • Matlab: plotting frequency distribution with a curve

    - by Kaly
    I have to plot 10 frequency distributions on one graph. In order to keep things tidy, I would like to avoid making a histogram with bins and would prefer having lines that follow the contour of each histogram plot. I tried the following [counts, bins] = hist(data); plot(bins, counts) But this gives me a very inexact and jagged line. I read about ksdensity, which gives me a nice curve, but it changes the scaling of my y-axis and I need to be able to read the frequencies from the y-axis. Can you recommend anything else?

    Read the article

  • Hilighting div tag in Masterpage on redirection to content page

    - by user1713632
    I have a link in Master page within a div tag. I want to highlight the div when I am clicking the link, in order to redirect to some content page. I have written the following code: <li> <div id="div_test" runat="server"> <asp:LinkButton ID="lnk_test_menu" Font-Underline="false" ForeColor="Black" runat="server" Text="Test Link" CausesValidation="false" onclick="lnk_test_menu_Click1" > </asp:LinkButton></div> </li> Code in the cs page: protected void lnk_test_menu_Click1(object sender, EventArgs e) { div_test.Attributes.Add("class", "testSelected"); Response.Redirect(Test.aspx"); } The div in the master page is not being selected on redirection. Could anybody help me on this?

    Read the article

  • SQL query to get lowest 2 values of a counted query selection (using db2)?

    - by jNoob
    Hi, Imagine I already have a query that returns the following: Col1 | Col2 ------------ A | 2 B | 3 C | 3 D | 4 E | 8 ... Say I used something like this: select Col1, count ( * ) as Col2 \ from ... where ... order by Col2 \ group by Col1 \ So now, all I want to select are (Col1, Col2) such that it returns the selections (a, b) and (c, d) where (b >= all (Col2)) and (d >= ((all (Col2)) - a)). So for the above example, it would return {(A, 2), (B, 3), (C, 3)}. How do I go about doing this? Any help would be highly appreciated. Thanks.

    Read the article

  • <hash_set> equality operator doesn't work in VS2010

    - by ProgramWriter
    Sample code: std::hash_set<int> hs1; // also i try std::unorded_set<int> - same effect std::hash_set<int> hs2; hs1.insert(15); hs1.insert(20); hs2.insert(20); hs2.insert(15); assert(hs1 == hs2); hash_set doesn't stores elements in some order defined by hash function... why? Please note that this code works in VS2008 using stdext::hash_set.

    Read the article

  • left join without duplicate values using MIN()

    - by Clipper87
    I have a table_1: id custno 1 1 2 2 3 3 and a table_2: id custno qty descr 1 1 10 a 2 1 7 b 3 2 4 c 4 3 7 d 5 1 5 e 6 1 5 f When I run this query to show the minimum order quantities from every customer: SELECT DISTINCT table_1.custno,table_2.qty,table_2.descr FROM table_1 LEFT OUTER JOIN table_2 ON table_1.custno = table_2.custno AND qty = (SELECT MIN(qty) FROM table_2 WHERE table_2.custno = table_1.custno ) Then I get this result: custno qty descr 1 5 e 1 5 f 2 4 c 3 7 d Customer 1 appears twice each time with the same minimum qty (& a different description) but I only want to see customer 1 appear once. I don't care if that is the record with 'e' as a description or 'f' as a description. How could I do this ? Thx!

    Read the article

  • Is it poor practice to identify objects via an enumeration property, instead of using GetType()?

    - by James
    I have a collection of objects that all implement one (custom) interface: IAuditEvent. Each object can be stored in a database and a unique numeric id is used for each object type. The method that stores the objects loops around a List<IAuditEvent>, so it needs to know the specific type of each object in order to store the correct numeric id. Is it poor practice to have an enumeration property on IAuditEvent so that each object can identify itself with a unique enumeration value? I can see that the simplest solution would be to write a method that translates a Type into an integer, but what if I need an enumeration of audit events for another purpose? Would it still be wrong to have my enumeration property on IAuditEvent?

    Read the article

  • Count, inner join

    - by Urosh
    I have two tables: DRIVER (Driver_Id,First name,Last name,...) PARTICIPANT IN CAR ACCIDENT (Participant_Id,Driver_Id-foreign key,responsibility-yes or no,...) Now, I need to find out which driver participated in accident where responsibility is 'YES', and how many times. I did this: Select Driver_ID, COUNT (Participant.Driver_ID)as 'Number of accidents' from Participant in car accident where responsibility='YES' group by Driver_ID order by COUNT (Participant.Driver_ID) desc But, I need to add drivers first and last name from the first table(using inner join, I suppose). I don't know how, because it is not contained in either an aggregate function or the GROUP BY clause. Please help :)

    Read the article

  • how to get the second batch and 3rd batch in the same query result in oracle sql + yii framework?

    - by sasori
    let' say i have 20 results in the sql query. if am gonna use the limit in the yii active record, I'll obviously get the first four from the result, but what if i wanna get the 2nd four and then 3rd four in the same query result ? how to query that via sql ? e.g $criteria2 = new CDbCriteria(); $criteria2->select = 'USERID, ADID ,ADTYPE, ADTITLE, ADDESC, PAGEVIEW, DISPPUBLISHDATE'; $criteria2->addCondition("STATUS = 1"); $criteria2->order = '"t".PAGEVIEW DESC,"t".PUBLISHDATE DESC'; $criteria2->limit = 4; $criteria2->with = array('subcat','adimages'); $result = $this->findAll($criteria2); return $result;

    Read the article

  • help with stored procedure

    - by I__
    i am looking at this site: http://cloudexchange.cloudapp.net/stackoverflow/s/84/rising-stars-top-50-users-ordered-on-rep-per-day set nocount on DECLARE @endDate date SELECT @endDate = max(CreationDate) from Posts set nocount off SELECT TOP 50 Id AS [User Link], Reputation, Days, Reputation/Days AS RepPerDays FROM ( SELECT *, CONVERT(int, @endDate - CreationDate) as Days FROM Users ) AS UsersAugmented WHERE Reputation > 5000 ORDER BY RepPerDays DESC i am also a beginner at SQL. i have the following questions about this code: is this mysql or mssql? what does this do? set nocount off why is this in brackets? [User Link] what does this do? CONVERT(int, @endDate - CreationDate) as Days thanks!

    Read the article

  • How do I select the most recent entry in mysql?

    - by ggfan
    i want to select the most recent entry from a table and see if that entry is exactly the same as the one the user is trying to enter. How do I do a query to "select * from the most recent entry of 'posting'"? $query="Select * FROM //confused here (SELECT * FROM posting ORDER BY date_added DESC) WHERE user_id='{$_SESSION['user_id']}' AND title='$title' AND price='$price' AND city='$city' AND state='$state' AND detail='$detail' "; $data = mysqli_query($dbc, $query); $row = mysqli_fetch_array($data); if(mysqli_num_rows($data)>0) { echo "You already posted this ad. Most likely caused by refreshing too many times."; echo "<br>"; $linkposting_id=$row['posting_id']; echo "See the <a href='ad.php?posting_id=$linkposting_id'>Ad</a>"; } else { ...insert into the dbc }

    Read the article

  • Sort vector<int>(n) in O(n) time using O(m) space?

    - by Adam
    I have a vector<unsigned int> vec of size n. Each element in vec is in the range [0, m], no duplicates, and I want to sort vec. Is it possible to do better than O(n log n) time if you're allowed to use O(m) space? In the average case m is much larger than n, in the worst case m == n. Ideally I want something O(n). I get the feeling that there's a bucket sort-ish way to do this: unsigned int aux[m]; aux[vec[i]] = i; Somehow extract the permutation and permute vec. I'm stuck on how to do 3. In my application m is on the order of 16k. However this sort is in the inner loops and accounts for a significant portion of my runtime.

    Read the article

< Previous Page | 485 486 487 488 489 490 491 492 493 494 495 496  | Next Page >