Search Results

Search found 16174 results on 647 pages for 'disk space'.

Page 565/647 | < Previous Page | 561 562 563 564 565 566 567 568 569 570 571 572  | Next Page >

• Is there a website to look up common, already written functions?

  - by pinnacler

  I'm sitting here writing a function that I'm positive has been written before, somewhere on earth. It's just too common to have not been attempted, and I'm wondering why I can't just go to a website and search for a function that I can then copy and paste into my project in 2 seconds, instead of wasting my day reinventing the wheel. Sure there are certain libraries you can use, but where do you find these libraries and when they are absent, is there a site like I'm describing? Possibly a wiki of some type that contains free code that anybody can edit and improve? Edit: I can code things fine, I just don't know HOW to do them. So for example, right now, I'm trying to localize a robot/car/point in space. I KNOW there is a way to do it, just based off of range and distance. Triangulation and Trilateration. How to code that is a different story. A site that could have psuedo code, step by step how to do that would be ridiculously helpful. It would also ensure the optimal solution since everybody can edit it. I'm also writing in Matlab, which I hate because it's quirky, adding to my desire for creating a website like I describe.

  Read the article

• Query Access and VB.NET

  - by yae

  Hi all: I have 2 tables: "products" and "pieces" PRODUCTS idProd product price PIECES id idProdMain idProdChild quant idProdMain and idProdChild are vinculated with the table: "products". Other considerations is that 1 product can have some pieces and 1 product can be a piece. Price product equal a sum of quantity * price of all their pieces. EXAMPLE: TABLE PRODUCTS (idProd - product - price) 1 - Computer - 300€ 2 - Hard Disk - 100€ 3 - Memory - 50€ 4 - Main Board - 100€ 5 - Software - 50€ 6 - CDroms 100 un. - 30€ TABLE PIECES (id - idProdMain - idProdChild - Quant.) 1 - 1 - 2 - 1 2 - 1 - 3 - 2 3 - 1 - 4 - 1 WHAT I NEED? I need update the price of the main product when the price of the product child (piece) is changed. Following the previous example, if I change the price of this product "memory" (is a piece too) to 60€, then product "Computer" will must change his price to 320€ How I can do it using queries? Already I have tried this to obatin the price of the main product, but not runs. This query not returns any value SELECT Sum(products.price*pieces.quant) AS Expr1 FROM products LEFT JOIN pieces ON (products.idProd = pieces.idProdChild) AND (products.idProd = pieces.idProdChild) AND (products.idProd = pieces.idProdMain) WHERE (((pieces.idProdMain)=5));

  Read the article

• Regex help in java validations

  - by user1697113

  Hi i want to do some validations.I used to put regex in JS but im new to regex in java, so i tried to make up a code on similar lines in java. Here is what i did. 1)Check whether first character in string is alphanumeric. 2)Check whether the string atleast 1 number. so i wrote a code, but it is always returning false.I am not sure if i'm doing this correctly. private static boolean checkEmbeddedPassword(final String field) { boolean returnValue=true; String testpatternAlpha="/^[A-Za-z0-9].+$/"; String testNumber="/[0-9]/"; Pattern pattern=Pattern.compile(testpatternAlpha); Pattern pattern2=Pattern.compile(testNumber); Matcher matcher = pattern.matcher(field); Matcher matcher2 = pattern2.matcher(field); boolean firstChar=matcher.matches(); boolean numberFlag=matcher2.matches(); System.out.println("-----the value of pwd iss-----"+field); System.out.println("---------Regex---------Out--put-----"+firstChar); System.out.println("---------Regex---------Out- for numeral-put-----"+numberFlag); if(firstChar){ returnValue=false; } else if(field.contains(" ")) { System.out.println("-----------cannot have space------"); returnValue=false; } else if(numberFlag) { returnValue=false; } return returnValue; }

  Read the article

• Vim, LaTeX, word-wrapping, and version control

  - by Bkkbrad

  I'm writing a LaTeX document in vim, and I have it hard wrapping at 80 characters to make reading easier. However, this causes problems with tracking changes with in version control. For example, inserting "Lorem ipsum" at the beginning of this text: 1 Dolor sit amet, consectetur adipiscing elit. Phasellus bibendum lobortis lectus 2 quis porta. Aenean vestibulum magna vel purus laoreet at molestie massa 3 suscipit. Vestibulum vestibulum, mauris nec convallis ultrices, tellus sapien 4 ullamcorper elit, dignissim consectetur justo tellus et nunc. results in: 1 Lorum ipsum dolor sit amet, consectetur adipiscing elit. Phasellus bibendum 2 lobortis lectus quis porta. Aenean vestibulum magna vel purus laoreet at 3 molestie massa suscipit. Vestibulum vestibulum, mauris nec convallis ultrices, 4 tellus sapien ullamcorper elit, dignissim consectetur justo tellus et nunc. When I review this change in git, it tells me that all the lines of the paragraph have changed because of the wrapping, even though only one semantic change has occurred. One way around this problem is to have every sentence on its own line. This looks the same in the rendered document, but the source now is harder to read, because each line has quite a different line length: 1 Lorum ipsum dolor sit amet, consectetur adipiscing elit. 2 Phasellus bibendum lobortis lectus quis porta. 3 Aenean vestibulum magna vel purus laoreet at molestie massa suscipit. 4 Vestibulum vestibulum, mauris nec convallis ultrices, tellus sapien ullamcorper elit, dignissim consectetur justo tellus et nunc. (If I soft wrap at 80, things still look bad, just in a different way.) Is it possible to have my text on disk with one newline per sentence, but display and edit it in vim as if the text of each paragraph was one long line, soft wrapped at 80 characters? I assume it requires some vim-foo rather than tweaking git or LaTeX.

  Read the article

• scrolling and css align with "right: 0px"

  - by Gabi

  Hello, In an HTML page, if I align some <div>s with "right: 0px", they all look very nice, as I expect. However, if I make the browser window smaller and the horizontal scroll bar appears, when I scroll the page to the right, I see an unexpected white space (instead of the background colors of my <div>s). It seems that my <div>s are aligned relative to the visible area of the page. See the sample code below: <html> <head> <style> <!-- #parent { position: absolute; left: 0px; right: 0px; top: 0px; bottom: 0px; background-color: yellow; } #child { position: absolute; left: 100px; top: 300px; width: 1000px; height: 400px; background-color: blue; } --> </style> </head> <body> <div id="parent"><div id="child">some text here</div></div> </body> </html> Is there any way to make the "right: 0px" property align the controls relative to the size of the entire page, not only the visible area? Thanks.

  Read the article

• Can't get data with spaces into the database from Ajax POST request

  - by J Jones

  I have a real simple form with a textbox and a button, and my goal is to have an asynchronous request (jQuery: $.ajax) send the text to the server (PHP/mysql a la Joomla) so that it can be added to a database table. Here's the javascript that is sending the data from the client: var value= $('#myvalue').val(); $.ajax( { type: "POST", url: "/administrator/index.php", data: { option: "com_mycomponent", task: "enterValue", thevalue: value, format: "raw"}, dataType: "text", success: reportSavedValue } ); The problem arises when the user enters text with a space in it. The $_POST variable that I receive has all the spaces stripped out, so that if the user enters "This string has spaces", the server gets the value "Thisstringhasspaces". I have been googling around, and have found lots of references that I need to use encodeURIComponent. So I have tried it, but now the value that I get from $_POST is "This20string20has20spaces". So it appears to be encoding it the way I would expect, only to have the percent signs stripped instead of the spaces, and leaving the hex numbers. I'm really confused. It seems that this sort of question is asked and answered everywhere on the web, and everywhere encodeURIComponent is hailed as the silver bullet. But apparently I'm fighting a different breed of lycanthrope. Does anyone have any suggestions?

  Read the article

• Make PasswordRecovery control work with locked out users ?

  - by Moe Sisko

  Example scenario in an ASP.NET application using SQL Server membership provider : 1) a user can't remember their exact password, and tries many times in a short space of time to login with an invalid password (say 5 times in a 10 minute window). This locks out the user (i.e. sets the IsLockedOut flag of the aspnet_Membership table to 1). 2) user goes to the "forgot my password" screen to try to get a new password emailed to them. This screen uses the PasswordRecovery control. User enters their correct user id, but then cannot go further in the password recovery process, since the IsLockedOut flag is 1. (They don't even get to see their security question). 3) The user would then have to phone tech support to get themselves unlocked etc. To reduce the burden on support staff, we are trying to eliminate step 3) if possible, by making the PasswordRecovery control (if possible), work with locked out users. i.e. when they enter their login ID, the security question comes up, and IF they enter the correct answer, the system will unlock the user, then send the new email to them. I'm wondering if it is possible to tweak the PasswordRecovery control to do this. Or maybe I'm approaching this the wrong way ?

  Read the article

• How to mark array value types in PHP (Java)Doc?

  - by Christian Sciberras

  It might be a bit difficult to explain, so I'll give some example code. Note that I'm using NetBeans IDE (latest). class Dummy { public function say(){ } } /** * Builds dummy class and returns it. * @return Dummy The dummy class. */ function say_something(){ return new Dummy(); } $s=say_something(); While developing in netbeans I can invoke auto-complete by hitting ctrl+space after typing "$s-". In the the hint window that follows, there is the item "say()". This is because the javadoc says say_something returns a Dummy and NetBeans parsed Dummy class to know that it has a method called "say()". So far so good. My problem is with arrays. Example code follows: /** * Builds array of 2 dummy classes and returns it. * @return Array The dummy class. (*) */ function say_something2(){ return array(new Dummy(),new Dummy()); } $s=say_something2(); If I try the auto-complete thing again but with "$s[0]-" instead, I don't get the methods fro Dummy class. This is because in the JavaDoc I only said that it is an array, but not the values' type. So the question would be, is there any JavaDoc syntax, cheat, whatever which allows me to tell JavaDoc what type of variables to expect in an array?

  Read the article

• sem-dynamic cdn

  - by dwi kristianto

  i'm developing couple of websites using php (directory script, etc.) and wordpress as cms. i need to improve its performance, by using cdn for static files (css, js, images). the problem is, css and javascript files are generated on the fly. i did that due to yahoo and some expert advice to combine the files into one file. also changing basic color of css files. for the time being, i use couple of small vps but still its not fast enough. i already contact maxcdn and the support guy said that they dont have such kind of services. what i need is: a cdn that will serve the request from user/visitor and there's no file in local disk, the cdn will redirect/fetch it from another domain/server. in vps, it could be done easily using combination of .htaccess and php, but NOT in the cdn. most of cdn only support purely static files. is there any such cdn that will server semi-dynamic files?

  Read the article

• Cleaning up a sparsebundle with a script

  - by nickg

  I'm using time machine to backup some servers to a sparse disk image bundle and I'd like to have a script to clean up the old back ups and re-size the image once space has been freed up. I'm fairly certain the data is protected because if I delete the old backups by right clicking, I have to enter a password to be able to delete them. To allow my script to be able to delete them, I've been running it as root. For some reason, it just won't run and every file it tries to delete I get rm: /file/: Operation not permitted Here is what I have as my script: #!/bin/bash for server in servername; do /usr/bin/hdiutil attach -mountpoint /path/to/mountpoint /path/to/sparsebundle/$server.sparsebundle/; /bin/sleep 10; /usr/bin/find /path/to/mountpoint -type d -mtime +7 -exec /bin/rm -rf {} \; /usr/bin/hdiutil unmount /path/to/mountpoint; /bin/sleep 10; /usr/bin/hdiutil compact /path/to/sparsebundle/$server.sparsebundle/; done exit; One of the problems I thought was causing this was it needed to have a mountpoint specified since the default mount was to /Volumes/Time\ Machine\ Backups/ that's why I created a mountpoint. I also thought that it was trying to delete the files to quickly after mounting and it wasn't actually mounted yet, that's why I added the sleep. I've also tried using the -delete option for find instead of -exec, but it didn't make any difference. Any help on this would be greatly appreciated because I'm out of ideas as to why this won't work.

  Read the article

• Having trouble plugging jQuery FullCalendar into Squarespace page

  - by ellenchristine

  When I test the fullcalendar widget locally, it works fine. However, when I try to integrate it with Squarespace, it doesn't show up. Here is what is in my head tag: <link rel='stylesheet' type='text/css' href='storage/scripts/fullcalendar.css' /> <script type='text/javascript' src='storage/scripts/jquery.js'></script> <script type='text/javascript' src='storage/scripts/fullcalendar.js'></script> <script type='text/javascript'> $(document).ready(function() { // page is now ready, initialize the calendar... $('#calendar').fullCalendar({ aspectRatio:2 }) }); </script> I have this in my body tag: <div id="calendar" style="width:500px; height:330px; background-color:#CCCCCC;"></div> The div displays but the calendar doesn't appear at all. I can't figure out why this isn't working! The calendar should definitely fit in the div space (at least it does locally). I've used jQuery with Squarespace before, and I don't see where my error is.

  Read the article

• dynamically created arrays

  - by DevAno1

  My task consists of two parts. First I have to create globbal char array of 100 elements, and insert some text to it using cin. Afterwards calculate amount of chars, and create dedicated array with the length of the inputted text. I was thinking about following solution : char[100]inputData; int main() { cin >> inputData >> endl; int length=0; for(int i=0; i<100; i++) { while(inputData[i] == "\0") { ++count; } } char c = new char[count]; Am I thinking good ? Second part of the task is to introduce in the first program dynamically created array of pointers to all inserted words. Adding a new word should print all the previous words and if there is no space for next words, size of the inputData array should be increased twice. And to be honest this is a bit too much for me. How I can create pointers to words specifically ? And how can I increase the size of global array without loosing its content ? With some temporary array ?

  Read the article

• MySQL multidimensional arrays...

  - by jay

  What is the best way to store data that is dynamic in nature using MySQL? Let's say I have a table in which one item is "dynamic". For some entries I need to store one value, but for others it could be one hundred values. For example let's say I have the following simple table: CREATE TABLE manager ( name char(50), worker_1_name(50), worker_2_name(50), ... worker_N_name(50) ); Clearly, this is not an ideal way to set up a database. Because I have to accommodate the largest group that a manager could potentially have, I am wasting a lot of space in the database. What I would prefer is to have a table that I can use as a member of another table (like I would do in C++ through inheritance) that can be used by the "manager" table to handle the variable number of employees. It might look something like this. CREATE TABLE manager ( name char(50), underlings WORKERS ); CREATE TABLE WORKERS ( name char(50), ); I would like to be able to add a variable number of workers to each manager. Is this possible or am I constrained to enumerating all the possible number of employees even though I will use the full complement only rarely?

  Read the article

• python VTE Terminal weirdness

  - by mykhal

  i'm trying to use the terminal from python VTE binding (python-vte from debian squeeze) as a virtual terminal emulator (just for ANSI/control chars text processing) in interactive python console, everything looks (almost) all right: >>> import vte >>> term = vte.Terminal() >>> term.feed("a\nb") >>> print repr(term.get_text(lambda *a: True).rstrip()) 'a\n b' however, launching this code (little modified) as python script, different result is yielded: $ python vte_wiredness_1.py '' strangely enough, pasting the code back into the (new) interactive python session also yields empty string: >>> import vte >>> term = vte.Terminal() >>> term.feed("a\nb") >>> print repr(term.get_text(lambda *a: True).rstrip()) '' >>> first thing caming on my mind was that the only difference between the two cases is the timing - there had to be some delay before get_text. unfortunately, preluding get_text with some seconds sleep did not help then i thought it has something to do with X window environment. but the results are the same pure linux console (with some warning on missing graphics). i wonder what causes such an unpredictable behavior (interactive console - pasted vs typed, and it's not the delay.. ant the interactive console has nothing to do with the vte terminal object.. i guess) can someone explain what is happening? is it possible to use the VTE Term such way? that the "b" letter in the output is preceded by the space, is another strangeness (all consecutive lines are preceded by more spaces.. looks like I have to send carriage return before the string.) (the lambda *a: True get_text method argument i'm using is a dummy callback, it's is some SlotSelectedCallback.. for its explanation i'd be grateful as well :) )

  Read the article

• atrribute value using msxml from xml

  - by edwards

  Hi I have the folowing XML <?xml version="1.0" encoding="ISO-8859-1" ?> - <DEVICEMESSAGES> <VERSION xml="1" checksum="" revision="0" envision="33050000" device="" /> <HEADER id1="0001" id2="0001" content="Nasher[<messageid>]: <!payload>" /> <MESSAGE level="7" parse="1" parsedefvalue="1" tableid="15" id1="24682" id2="24682" eventcategory="1003010000" content="Access to <webpage> was blocked due to its category (<info> by <hostname>)" /> </DEVICEMESSAGES> I am using the following xslt <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="text"/> <xsl:strip-space elements="*"/> <xsl:template match="DEVICEMESSAGES"> <xsl:value-of select="@id2"/>,<xsl:text/> <xsl:value-of select="@content"/>,<xsl:text/> <xsl:text>&#xa;</xsl:text> </xsl:template> </xsl:stylesheet> when i use MSXML i just get ,, whereas i want to have something like id2, content 0001 , Nasher[]: "

  Read the article

• Netbeans (PHP) catching syntax error on xml declaration

  - by Mike Valeriano

  Hello. I've just installed and configured Netbeans to work with PHP (including xdebug), and almost everything is working as intended, except that I've been getting "errors" in the IDE after I edited the default webpage template to comply with xhtml 1.1. The template is this: <?xml version="1.0" encoding="${project.encoding}" ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=${project.encoding}" /> <title></title> </head> <body> </body> </html> These are the errors I receive (I can't post images yet). Page is created OK, character encoding is inherited from project's settings as expected. It's probably something to do with the xml declaration on top of the document, but I don't really know how to "tune" Netbeans to ignore it and not show the 3 errors on every page I create. The warning is there because NB does not recognize the xhtml 1.1 DTD, so it falls back to html 4.01, which does not support the xmlns attribute in the html tag - and that's the only thing I could find searching around. It will be fixed in the next version, so I'm not worried about it. I know there's nothing wrong with the markup, but there's probably something I'm missing in NB configuration, and I would like to get rid of those messages because they pretty much take all the space I reserve for errors/warnings/tasks. So is there any way I can either make NB recognize this xml declaration or make it ignore these specific "errors"? Thanks.

  Read the article

• php: replacing double <br /> with </p><p>

  - by andufo

  i use nicEdit to write RTF data in my CMS. The problem is that it generates strings like this: hello first line<br><br />this is a second line<br />this is a 3rd line since this is for a news site, i much prefer the final html to be like this: <p>hello first line</p><p>this is a second line<br />this is a 3rd line</p> so my current solution is this: i need to trim the $data for <br /> at the start/end of the string replace <br /><br /> with </p><p> (one single <br /> is allowed). finally, add <p> at the start and </p> at the end i only have the 3rd step so far. can someone give me a hand with steps 1 and 2? function replace_br($data) { # step 3 $data = '<p>'.$data.'</p>'; return $data; } thanks! ps: it would be even better to avoid specific situations. example: "hello<br /><br /><br /><br /><br />too much space" -- those 5 breaklines should also be converted to just one "</p><p>"

  Read the article

• How do I find Microsoft APIs?

  - by Stephen

  I'm a java programmer, and if I see something that: I don't know about or just want to find a method description without opening an ide or am on support I type java [classname] into google, and there it is. If I try this crazy stunt for C# I'll come up with a whole heap of tutorials (how do I use it etc). If I manage to get to MSDN, I have to wade through a page describing every .net technology to see how their syntax references the same object, and then I have to find the appropriate page from there ([class name] Constructor) for example. This is even more pronounced, because I don't have Visual Studio, so I've got nothing to make it easier. There must be something I'm missing or don't know... how does this situation work for Microsoft developers? how can I make my life easier/searches better? are there techniques that work no matter what computer I'm on (e.g. require no computer setup/downloads) Notes It could be thought that java is just "java", but it's just that the java apis are only referenced/defined in the core language. For all the other languages on the JVM, it's assumed that you will just learn the correct syntax to use the java apis. I presume that .Net only lists a whole heap of languages as the api classes are actually different and have different interfaces capabilities (or some approximation of this presumption). Edit While searching msdn works... in the java space I can type 'java [anyclass]' and it will generally be found... whether it's a java core api or a third party library

  Read the article

• MKL Accelerated Math Libraries for Java...

  - by Kaopua

  I've looked at the related threads on StackOverflow and Googled with not much luck. I'm also very new to Java (I'm coming from a C# and .NET background) so please bear with me. There is so much available in the Java world it's pretty overwhelming. I'm starting on a new Java-on-Linux project that requires some heavy and highly repetitious numerical calculations (i.e. statistics, FFT, Linear Algebra, Matrices, etc.). So maximizing the performance of the mathematical operations is a requirement, as is ensuring the math is correct. So hence I have an interest in finding a Java library that perhaps leverages native acceleration such as MKL, and is proven (so commercial options are definitely a possibility here). In the .NET space there are highly optimized and MKL accelerated commercial Mathematical libraries such as Centerspace NMath and Extreme Optimization. Is there anything comparable in Java? Most of the math libraries I have found for Java either do not seem to be actively maintained (such as Colt) or do not appear to leverage MKL or other native acceleration (such as Apache Commons Math). I have considered trying to leverage MKL directly from Java myself (e.g. JNI), but me being new to Java (let alone interoperating between Java and native libraries) it seemed smarter finding a Java library that has already done this correctly, efficiently, and is proven. Again I apologize if I am mistaken or misguided (even in regarding any libraries I've mentioned) and my ignorance of the Java offerings. It's a whole new world for me coming from the heavily commercialized Microsoft stock so I could easily be mistaken on where to look and regarding the Java libraries I've mentioned. I would greatly appreciate any help or advice.

  Read the article

• Error Converting PIL B&W images to Numpy Arrays

  - by Elliot

  I am getting weird errors when I try to convert a black and white PIL image to a numpy array. An example of the code I am working with is below. if image.mode != '1': image = image.convert('1') #convert to B&W data = np.array(image) #convert data to a numpy array n_lines = data.shape[0] #number of raster passes line_range = range(data.shape[1]) for l in range(n_lines): # process one horizontal line of the image line = data[l] for n in line_range: if line[n] == 1: write_line_to(xl, z+scale*n, speed) #conversion to other program code elif line[n] == 0: run_to(xl, z+scale*n) #conversion to other program code I have tried this using both array and asarray for the conversion, and gotten different errors. If I use array, then the data I get out is nothing like what I put in. It looks like several very shrunken partial images side by side, with the remainder of the image space filled in in black. If I use asarray, then the entirety of python crashes during the raster step (on a random line). If I work with a greyscale image ('L'), then neither of these errors occurs for either array or asarray. Does anyone know what I am doing wrong? Is there something odd about the way PIL encodes B&W images, or something special I need to pass numpy to make it convert properly?

  Read the article

• error detection/correction/recovery in serial protocols

  - by Jason S

  I have some designing to do for a serial protocol and am running into some questions that I figure must have been considered elsewhere. So I'm wondering if there are some recommendations for best practices in designing serial protocols. (Please either state a fact that is easily verifiable, or cite a reputable source if you make a claim.) General recommendations for websites/books are also welcome. In particular I have to deal with issues like parsing a stream of bytes into packets verifying a packet is correct (easy with a CRC, for instance) identifying reasonable types of errors that can occur (e.g. in a point-to-point serial stream, sporadic single bit errors, and dropped series of bytes, are both likely, but extra phantom bytes are unlikely; whereas with a record stored in flash memory or on a disk drive the types of errors that predominate are different) error correction or recovery (if I detect an error in a packet, can I correct it? If not, can I resync to the boundary of the next packet?) how to make variable-length packets robust to error correction / recovery. Any suggestions?

  Read the article

• How does one create and use a pointer to an array of an unknown number of structures inside a class?

  - by user1658731

  Sorry for the confusing title... I've been playing around with C++, working on a project to parse a game's (Kerbal Space Program) save file so I can modify it and eventually send it over a network. I'm stuck with storing an unknown number of vessels and crew members, so I need to have an array of unknown size. Is this possible? I figured having a pointer to an array would be the way to go. I have: class SaveFileSystem { string version; string UT; int activeVessel; int numCrew; ??? Crews; // !! int numVessels; ??? Vessels; // !! } Where Crews and Vessels should be arrays of structures: struct Crew { string name; //Other stuff }; struct Vessel { string name; //Stuff }; I'm guessing I should have something like: this->Crews = new ???; this->Vessels = new ???; in my constructor to initialize the arrays, and attempt to access it with: this->Crews[0].name = "Ship Number One"; Does this make any sense??? I'd expect the "???"'s to involve a mess of asterisk's, like "*struct (*)Crews" but I have no real idea. I've got normal pointers down and such, but this is a tad over my head... I'd like to access the structures like in the last snippet, but if C++ doesn't like that I could do pointer arithmetic. I've looked into vectors, but I have an unhealthy obsession with efficiency, and it really pains me how you don't know what's going on behind it.

  Read the article

• QuadTrees - how to update when internal items are moving

  - by egarcia

  I've implemented a working QuadTree. It subdivides 2-d space in order to accomodate items, identified by their bounding box (x,y,width,height) on the smallest possible quad (up to a minimum area). My code is based on this implementation (mine is in Lua instead of C#) : http://www.codeproject.com/KB/recipes/QuadTree.aspx I've been able to successfully implement insertions and deletions successfully. I've turn now my attention to the update() function, since my items' position and dimensions change over time. My first implementation works, but it is quite naïve: function QuadTree:update(item) self:remove(item) return self.root:insert(item) end Yup, I basically remove and reinsert every item every time they move. This works, but I'd like to optimize it a bit more; after all, most of the time, moving items still remain on the same quadTree node most of the iterations. Is there any standard way to deal with this kind of update? In case it helps, my code is here: http://github.com/kikito/passion/blob/master/ai/QuadTree.lua I'm not looking for someone to implement it for me; pointers to an existing working implementation (even in other languages) would suffice.

  Read the article

• XElement vs Dcitionary

  - by user135498

  Hi All, I need advice. I have application that imports 10,000 rows containing name & address from a text file into XElements that are subsequently added to a synchronized queue. When the import is complete the app spawns worker threads that process the XElements by deenqueuing them, making a database call, inserting the database output into the request document and inserting the processed document into an output queue. When all requests have been processed the output queue is written to disk as an XML doc. I used XElements for the requests because I needed the flexibility to add fields to the request during processing. i.e. Depending on the job type the app might require that it add phone number, date of birth or email address to a request based on a name/address match against a public record database. My questions is; The XElements seems to use quite a bit of memory and I know there is a lot of parsing as the document makes its way through the processing methods. I’m considering replacing the XElements with a Dictionary object but I’m skeptical the gain will be worth the effort. In essence it will accomplish the same thing. Thoughts?

  Read the article

• Why do System.IO.Log SequenceNumbers have variable length?

  - by Doug McClean

  I'm trying to use the System.IO.Log features to build a recoverable transaction system. I understand it to be implemented on top of the Common Log File System. The usual ARIES approach to write-ahead logging involves persisting log record sequence numbers in places other than the log (for example, in the header of the database page modified by the logged action). Interestingly, the documentation for CLFS says that such sequence numbers are always 64-bit integers. Confusingly, however, the .Net wrapper around those SequenceNumbers can be constructed from a byte[] but not from a UInt64. It's value can also be read as a byte[], but not as a UInt64. Inspecting the implementation of SequenceNumber.GetBytes() reveals that it can in fact return arrays of either 8 or 16 bytes. This raises a few questions: Why do the .Net sequence numbers differ in size from the CLFS sequence numbers? Why are the .Net sequence numbers variable in length? Why would you need 128 bits to represent such a sequence number? It seems like you would truncate the log well before using up a 64-bit address space (16 exbibytes, or around 10^19 bytes, more if you address longer words)? If log sequence numbers are going to be represented as 128 bit integers, why not provide a way to serialize/deserialize them as pairs of UInt64s instead of rather-pointlessly incurring heap allocations for short-lived new byte[]s every time you need to write/read one? Alternatively, why bother making SequenceNumber a value type at all? It seems an odd tradeoff to double the storage overhead of log sequence numbers just so you can have an untruncated log longer than a million terabytes, so I feel like I'm missing something here, or maybe several things. I'd much appreciate it if someone in the know could set me straight.

  Read the article

< Previous Page | 561 562 563 564 565 566 567 568 569 570 571 572  | Next Page >