Search Results

Search found 3311 results on 133 pages for 'computing theory'.

Page 109/133 | < Previous Page | 105 106 107 108 109 110 111 112 113 114 115 116  | Next Page >

• Computer science textbooks

  - by Barrett Conrad

  I would like to try the book question a little bit differently. My goal is to know what the community thinks are the quintessential computer science textbooks. <beginsadstory>I lost all of my computer science and math books from college in Hurricane Katrina in 2005. I greatly miss having my familiar tomes to refer to when topics and problems come up, so I am looking to rebuild my library.<endsadstory> What are your recommendations for the best examples of academic caliber books for the field of computer science and its associated mathematics? I am looking for books on subjects like computational theory, programming languages, compilers, operating systems, algorithms and so on. Don't limit your suggestions to your textbooks only. If there is a book you have read that covers computer science or a related math in a formal way, but is not strictly a textbook, I would be love to hear about them as well. Finally, for the sake of creating a good reference for all of us, may I suggest posting one book per answer so they can be rated individually.

  Read the article

• What's all this fuss about?

  - by atch

  Hi guys, At the beginning I want to state that it is not my intention to upset anyone who uses/like language other than C++. I'm saying that due to the fact that on one forum everytime when I've tried to ask questions of similiar nature I was almost always accused of trying to create a raw. Ok that's having done this is my question: I don't understand why java/c# creators thought/think that having something like vm and having source code compiled to bytecode instead of native code is in a long run any advantage. And why having function compiled for a first time when they are invoked is any advantege? And what's the story about write once run everywhere? When I think about the business of having something written once and it can run everywhere - well in theory this is all well. But I know for a fact that in practice it doesn't look that well at all. It is rather like write once test everywhere. And why would I preffer something to be compiled on runtime instead of compiletime. If I would have to wait even one hour longer for program to be installed once and for all and all the compilation would be done and nothing would be compiled after that I would preffer that. And I don't really know how it works in the real world (I'm a student never worked in IT business) but for example if I have working program written in C++ for Windows and I have wish to move it to another platform wouldn't I have to take my source code and compile it on desired machine? So in other words isn't that rather problem of having compiler which will compile source code on different machines (as far as I'm concerned there is just one C++ and source code will look identical in every machine). And last but not least if you think about it how many programs they are which are really word porting? I personnally can think of 3 maybe four.

  Read the article

• Choosing random numbers efficiently

  - by Frederik Wordenskjold

  I have a method, which uses random samples to approximate a calculation. This method is called millions of times, so its very important that the process of choosing the random numbers is efficient. I'm not sure how fast javas Random().nextInt really are, but my program does not seem to benefit as much as I would like it too. When choosing the random numbers, I do the following (in semi pseudo-code): // Repeat this 300000 times Set set = new Set(); while(set.length != 5) set.add(randomNumber(MIN,MAX)); Now, this obviously has a bad worst-case running time, as the random-function in theory can add duplicated numbers for an eternity, thus staying in the while-loop forever. However, the numbers are chosen from {0..45}, so a duplicated value is for the most part unlikely. When I use the above method, its only 40% faster than my other method, which does not approximate, but yields the correct result. This is ran ~ 1 million times, so I was expecting this new method to be at least 50% faster. Do you have any suggestions for a faster method? Or maybe you know of a more efficient way of generation a set of random numbers.

  Read the article

• WCF- "The underlying connection was closed: The connection was closed unexpectedly"

  - by SumGuy

  Hi there. I'm recieving that wonderfuly ambiguous error message when using one of my webmethods on my WCF webservice. As that error message doesn't provide any explanation whatsoever allow me to post my theory. I believe it may have something to do with the return type I'm using I have a Types DLL which is refrenced in both the webservice and the client. In this DLL is the base class ExceptionMessages. There is a child of this class called DrawingExcepions. Here is some code: public class ExceptionMessages { public object[] ReturnValue { get; set; } } public class DrawingExceptions : ExceptionMessages { private List<DrawingException> des = new List<DrawingException>(); } public class DrawingException { public Exception ExceptionMsg { get; set; } public List<object> Errors { get; set; } } The using code: [OperationContract] ExceptionMessages createNewBom(Bom bom, DrawingFiles dfs); public ExceptionMessages createNewBOM(Bom bom, DrawingFiles dfs) { return insertAssembly(bom, dfs); } public DrawingExceptions insertAssembly(Bom bom, DrawingFiles dfs) { DrawingExceptions des = new DrawingExceptions(); foreach (DrawingFile d in dfs.drawingFiles) { DrawingException temp = insertNewDrawing(bom, d); if (temp != null) des.addDrawingException(temp); if (d.Child != null) des.addDrawingException(insertAssembly(bom, d.Child)); } return des; } Returns to: ExceptionMessages ems = client.createNewBom(bom, currentDFS); if (ems is DrawingExceptions) { } Basically the return type from the webmethod is ExceptionMessages however I would usually be sending the child class back instead. My only idea is that it's the child that's causing the error but as far as I've read, this should have no effect. Has anyone got any ideas what could be going wrong here? If any more info is required, just ask :) Thanks.

  Read the article

• CS Master's Degree Project vs. Thesis options

  - by Nwosh

  I'm doing a master's degree in computer science, and I'm currently at the point where I have to decide between the thesis and non-thesis options offered by my university. The thesis option was my first choice, it entails taking less courses but tends to take more time doing your thesis. The non-thesis option involves taking more coursework, taking a comprehensive exam, and doing a project in one semester with a faculty member. I'd like to pursue a PhD degree eventually (although not right away, I want to get some years of professional experience first), and I heard that having demonstrated the ability to work on a thesis helps a lot with admission (like: not doing thesis raises questions and suggests not being interested in research) and that the experience itself is very good. At the same time, almost everyone I know who did a thesis at my university took a long time (2-3 years), in theory it could be done in 1.5 years. I'm a part time student and I don't really want to spend so much time just getting a master's degree, I could still publish a few papers while working on the project option and I'd be done in a year or so, additionally, I heard having a master's degree with a project and more coursework is more desirable for the industry. So, when applying for a PhD degree in CS at some of the better universities, would the time spent working on the master's thesis help in getting me accepted? Or should I opt for the non-thesis option and hope that the extra coursework and publishing some papers would make up for not working on a thesis?

  Read the article

• Getting browser to make an AJAX call ASAP, while page is still loading

  - by Chris

  I'm looking for tips on how to get the browser to kick off an AJAX call as soon as possible into processing a web page, ideally before the page is fully downloaded. Here's my approximate motivation: I have a web page that takes, say, 5 seconds to load. It calls a web service that takes, say, 10 seconds to load. If loading the page and calling the web service happened sequentially, the user would have to wait 15 seconds to see all the information. However, if I can get the web service call started before the 5 second page load is complete, then at least some of the work can happened in parallel. Ideally I'd like as much of the work to happen in parallel as possible. My initial theory was that I should place the AJAX-calling javascript as high up as possible in the web page HTML source (being mindful of putting it after the jquery.js include, because I'm making the call using jquery ajax). I'm also being mindful not to wrap the AJAX call in a jquery ready event handler. (I mention this because ready events are popular in a lot of jquery example code.) However, the AJAX call still doesn't seem to get kicked off as early as I'm hoping (at least as judged by the Google Chrome "Timeline" feature), so I'm wondering what other considerations apply. One thing that might potentially be detrimental is that the AJAX call is back to the same web server that's serving the original web page, so I might be in danger of hitting a browser limit on the # of HTTP connections back to that one machine? (The HTML page loads a number of images, css files, etc..)

  Read the article

• Flash movies in inactive browser tabs pause or don't execute in real time

  - by ZenBlender

  I'm noticing some unexpected behavior. Some time in the last few months, a change in either Firefox, the Flash player, or both, has made it so that Flash movies that are in inactive browser tabs no longer execute in real time. They appear to still execute, but only in bursts, and not in a predictable way. This is a problem because I develop a Flash-based (Actionscript 2.0, Flash CS3) multiplayer game that maintains a network connection and allows players to chat, etc. Many of our players complain about Firefox crashing while playing the game. I have noticed it too, not too frequently, but it crashes several times a week. (Firefox crashes, I do not get a message from Flash player that indicates an infinite loop or problem in my code) My theory is that this new behavior is causing crashes when there is a lot of activity in my game, leading to lots of unhandled network traffic for my game getting buffered before Firefox/Flash will give it a chance to execute. Maybe this leads to a buffer overflow or missing packets, and as a result, something crashes. At times I will switch back to the tab that is running my game and discover a display bug, which looks as though Flash has simply failed to execute something that it was supposed to. I would assume this new behavior is on purpose, for example to prevent all the Flash-based advertisements in inactive tabs from executing and therefore killing performance. In a quick test on Chrome (5.0.342.9 beta), this "pausing" of Flash seems to be there as well, but somehow it seems much less of a problem. My users have only complained about Firefox crashing, not other browsers. My machine: Windows 7 x64 Firefox 3.6.3 Flash Player 10.1.50.426 My game: triplejack.com Any ideas? Ideally I'd like to disable this behavior for my Flash game so it can execute in real time even when in an inactive tab. Thanks for any help!

  Read the article

• Subdomain on different host

  - by mattsmith321

  Hi everyone! I'm trying to host a subdomain for my site with a different hosting company and I'm running into issues on how to set it up. Here are the specifics: - Domain is registered with GoDaddy. - Nameservers are pointing to DiscountASP.net where ASP.NET app has been happily running for couple of years. - Would like blog.mydomain.com to point to my account with DreamHost.com to take advantage of their LAMP stack. I have added blog.mydomain.com to DreamHost (after adding mydomain.com) via their control panel. I thought I would be able to add a subdomain entry on GoDaddy to point to DreamHost, but all they allow is blog.mydomain.com = new url. In theory I could just take our .biz or .net domain and host it on DreamHost but was hoping I could do it all with a subdomain. So, to summarize I'd like to know if what I want to do is feasible and if so, how do I go about it (given the constraints of GoDaddy, DiscountASP, & DreamHost). Thanks, Matt

  Read the article

• F# and .Net versions

  - by rwallace

  I'm writing a program in F# at the moment, which I specified in the Visual Studio project setup to target .Net 3.5, this being the highest offered, on the theory that I might as well get the best available. Then I tried just now running the compiled program on an XP box, not expecting it to work, but just to see what would happen. Unsurprisingly I just got an error message demanding an appropriate version of the framework, but surprisingly it wasn't 3.5 it demanded, but 2.0.50727. An additional puzzle is the version of MSBuild I'm using to compile the release version of the program, which I found in the framework 3.5 directory but claims to be framework 2.0 and build engine 3.5. I just guessed it was the right version of MSBuild to use because it seemed to correspond with the highest framework version F# seems to be able to target, but should I be using a different version? Anyone have any idea what's going on? C:\Windows>dir/s msbuild.exe Volume in drive C is OS Volume Serial Number is 0422-C2D0 Directory of C:\Windows\Microsoft.NET\Framework\v2.0.50727 27/07/2008 19:03 69,632 MSBuild.exe 1 File(s) 69,632 bytes Directory of C:\Windows\Microsoft.NET\Framework\v3.5 29/07/2008 23:40 91,136 MSBuild.exe 1 File(s) 91,136 bytes Directory of C:\Windows\Microsoft.NET\Framework\v4.0.30319 18/03/2010 16:47 132,944 MSBuild.exe 1 File(s) 132,944 bytes Directory of C:\Windows\winsxs\x86_msbuild_b03f5f7f11d50a3a_6.0.6000.16386_none_815e96e1b0e084be 20/10/2006 02:14 69,632 MSBuild.exe 1 File(s) 69,632 bytes Directory of C:\Windows\winsxs\x86_msbuild_b03f5f7f11d50a3a_6.0.6000.16720_none_81591d45b0e55432 27/07/2008 19:00 69,632 MSBuild.exe 1 File(s) 69,632 bytes Directory of C:\Windows\winsxs\x86_msbuild_b03f5f7f11d50a3a_6.0.6000.20883_none_6a9133e9ca879925 27/07/2008 18:55 69,632 MSBuild.exe 1 File(s) 69,632 bytes C:\Windows>cd Microsoft.NET\Framework\v3.5 C:\Windows\Microsoft.NET\Framework\v3.5>msbuild /ver Microsoft (R) Build Engine Version 3.5.30729.1 [Microsoft .NET Framework, Version 2.0.50727.3053] Copyright (C) Microsoft Corporation 2007. All rights reserved. 3.5.30729.1

  Read the article

• Where can I find clear examples of MVC?

  - by Tom

  I've read a couple of things about MVCs but I still don't understand when they should be used and when they shouldn't be used. I am looking for clear examples that say things like "if you're developing this then you should use MVC, like this" and "if you're developing this, you shouldn't use MVC." Most of the examples I've seen rely on complex frameworks which have already implemented everything and you have to learn the framework and use it a lot to understand what's really happening. To many programmers, phrasings such as "UI business logic" sound like marketing terms — for example, the words "Instead the View binds directly to a Presentation Model" are used in this post. I am aware of the dangers that may lurk in the shadows as MVC is a concept and everyone feels like they know it best, yet nobody really knows exactly how to use it because there may be a lot of variables involved and everyone is allowed to have a different perspective on how to dissect a project into the Model, the View and the Controller. There is a lot of theory out there but very few clear examples. What I'm looking for are not "the best" ways of doing it so this should not be considered as subjective; I'm looking for different simple implementations that would allow me to decide on my own which are the best approaches. Succinctly: What are good on-line resources that present pro and con arguments to using MVC in various situations and provide clear examples to help the reader understand the concept?

  Read the article

• Evolutionary Algorithms: Optimal Repopulation Breakdowns

  - by Brian MacKay

  It's really all in the title, but here's a breakdown for anyone who is interested in Evolutionary Algorithms: In an EA, the basic premise is that you randomly generate a certain number of organisms (which are really just sets of parameters), run them against a problem, and then let the top performers survive. You then repopulate with a combination of crossbreeds of the survivors, mutations of the survivors, and also a certain number of new random organisms. Do that several thousand times, and efficient organisms arise. Some people also do things like introduce multiple "islands" of organisms, which are seperate populations that are allowed to crossbreed once in awhile. So, my question is: what are the optimal repopulation percentages? I have been keeping the top 10% performers, and repopulating with 30% crossbreeds and 30% mutations. The remaining 30% is for new organisms. I have also tried out the multiple island theory, and I'm interested in your results on that as well. It is not lost on me that this is exactly the type of problem an EA could solve. Are you aware of anyone trying that? Thanks in advance!

  Read the article

• Managing common components with Fossil CVS

  - by Larry Lustig

  I'm a Fossil (and CVS configuration novice) attempting to create and manage a set of distributed Fossil repositories for a Delphi project. I have the following directory tree: Projects Some Project Delphi Components LookupListView Some Client Some Project For Client Some Other Project For Client Source Code Project Resources Project Database I am setting up Fossil version control in order to version and share Projects\Some Client\Some Other Project For Client\Source Code, which contains Delphi 2010 source for a database project. This project makes use of Projects\Delphi Components\LookupListView which is a Delphi component. I need this code to be included in the versioning system for my project. I will, in theory, need to include it in other Fossil repositories in the future, as well. If I create my Fossil repository at the Source Code or Some Other Project For Client level, I cannot add any code above that level to my repository. What is the proper way to deal with this? The two solutions that occur to me are 1) Creating a separate repository for LookupListView and make sure that everyone who uses a repository for a project that references it "knows" that they must also get the current version of this project as well. This seems to defeat the purpose of being able to obtain a complete, current version of the project with a single checkout. The problem is magnified because there are other common component dependencies in this project. 2) Establishing my Fossil repository in the Projects directory, so I can check in files from various subfolders. This seems to me to involve an awful lot of extra path-typing when doing adds, and also to impose my directory structure (Some Client\Some Other Project For Client\Source) on the other users of the repository -- in this case, the actual client. Any suggestions appreciated.

  Read the article

• java.net.SocketException: Software caused connection abort: recv failed; Causes and cures?

  - by IVR Avenger

  Hi, all. I've got an application running on Apache Tomcat 5.5 on a Win2k3 VM. The application serves up XML to be consumed by some telephony appliances as part of our IVR infrastructure. The application, in turn, receives its information from a handful of SOAP services. This morning, the SOAP services were timing out intermittently, causing all sorts of Exceptions. Once these stopped, I noticed that our application was still performing very slowly, in that it took it a long time to render and deliver pages. This sluggishness was noticed both on the appliances that consume the Tomcat output, and from a simple test of requesting some static documents from my web browser. Restarting Tomcat immediately resolved the issue. Cracking open the localhost log, I see a ton of these errors, right up until I restarted Tomcat: WARNING: Exception thrown whilst processing POSTed parameters java.net.SocketException: Software caused connection abort: recv failed After a big of Googling, my working theory is that the SOAP issue caused my users to get errors, which caused them to make more requests, which put an increased load on the application. This caused it to run out of available sockets to handle incoming requests. So, here's my quandary: 1. Is this a valid hypothesis, or am I just in over my head with HTTP and Tomcat? 2. If this is a valid hypothesis, is there a way to increase the size of the "socket queue", so that this doesn't happen in the future? Thanks! IVR Avenger

  Read the article

• Java Playing Cards Game Framework

  - by isme

  My friends and I at uni love playing Shithead into the wee hours. But soon we graduate and will leave town, so probably won't get together for a game for a while. I want to develop a Java app we can use to play Shithead and our other favorites over a network. An app like this already exists, but is ugly, buggy and does not support our house rules. The source is available, but is such a mess that I would really rather start from scratch than try to refactor it! Building my game using some standard playing card api or framework, if such a thing exists, would be better than starting from scratch. The answer to a similar SO question was to use the JPC-API, which allegedly provides basic playing card services and rendering. But this Sourceforge project currently makes available no files or source code! Is there an alternative, or somewhere else to find this framework? Soon I will need help with the following as well: Lobby services (finding other players) Gaming network protocol (to communicate moves between players) Gaming theory (to write the computer opponent) Winning condition detection Game UI development

  Read the article

• Optimized Publish/Subcribe JMS Broker Cluster and Conflicting Posts on StackOverFlow for the Answer

  - by Gene

  Hi, I am looking to build a publish/subscribe distributed messaging framework that can manage huge volumes of message traffic with some intelligence at the broker level. I don't know if there's a topology that describes this, but this is the model I'm going after: EXAMPLE MODEL A A) There are two running message brokers (ideally all on localhost if possible, for easier demo-ing) : Broker-A Broker-B B) Each broker will have 2 listeners and 1 publisher. Example Figure [subscriber A1, subscriber A2, publisher A1] <-- BrokerA <-- BrokerB <-- [publisher B1, subscriber B1, subscriber B2] IF a message-X is published to broker A and there no subscribers for it among the listeners on Broker-B (via criteria in Message Selectors or Broker routing rules), then that message-X will never be published to Broker-B. ELSE, broker A will publish the message to broker B, where one of the broker B listeners/subscribers/services is expecting that message based on the subscription criteria. Is Clustering the Correct Approach? At first, I concluded that the "Broker Clustering" concept is what I needed to support this. However, as I have come to understand it, the typical use of clustering entails either: message redundancy across all brokers ... or Competing Consumers pattern ... and neither of these satisfy the requirement in the EXAMPLE MODEL A. What is the Correct Approach? My question is, does anyone know of a JMS implementation that supports the model I described? I scanned through all the stackoverflow post titles for the search: JMS and Cluster. I found these two informative, but seemingly conflicting posts: Says the EXAMPLE MODEL A is/should-be implicitly supported: http://stackoverflow.com/questions/2255816/jms-consumer-with-activemq-network-of-brokers " this means you pick a broker, connect to it, and let the broker network sort it out amongst themselves. In theory." Says the EXAMPLE MODEL A IS NOT suported: http://stackoverflow.com/questions/2017520/how-does-a-jms-topic-subscriber-in-a-clustered-application-server-recieve-message "All the instances of PropertiesSubscriber running on different app servers WILL get that message." Any suggestions would be greatly appreciated. Thanks very much for reading my post, Gene

  Read the article

• Secure Password Storage and Transfer

  - by Andras Zoltan

  I'm developing a new user store for my organisation and am now tackling password storage. The concepts of salting, HMAC etc are all fine with me - and want to store the users' passwords either salted and hashed, HMAC hashed, or HMAC salted and hashed - not sure what the best way will be - but in theory it won't matter as it will be able to change over time if required. I want to have an XML & JSON service that can act as a Security Token Service for client-side apps. I've already developed one for another system, which requires that the client double-encrypts a clear-text password using SHA1 first and then HMACSHA1 using a 128 unique key (or nonce) supplied by the server for that session only. I'd like to repeat this technique for the new system - upgrading the algo to SHA256 (chosen since implementations are readily available for all aforementioned platforms - and it's much stronger than SHA1) - but there is a problem. If I'm storing the password as a salted hash in the user-store, the client will need to be sent that salt in order to construct the correct hash before being HMACd with the unique session key. This would completely go against the point of using a salt in the first place. Equally, if I don't use salt for password storage, but instead use HMAC, it's still the same problem. At the moment, the only solution I can see is to use naked SHA256 hashing for the password in the user store, so that I can then use this as a starting point on both the server and the client for a more secure salted/hmacd password transfer for the web service. This still leaves the user store vulnerable to a dictionary attack were it ever to be accessed; and however unlikely that might be - assuming it will never happen simply doesn't sit well with me. Greatly appreciate any input.

  Read the article

• SIMPLE PHP MVC Framework!

  - by Allen

  I need a simple and basic MVC example to get me started. I dont want to use any of the available packaged frameworks. I am in need of a simple example of a simple PHP MVC framework that would allow, at most, the basic creation of a simple multi-page site. I am asking for a simple example because I learn best from simple real world examples. Big popular frameworks (such as code ignighter) are to much for me to even try to understand and any other "simple" example I have found are not well explained or seem a little sketchy in general. I should add that most examples of simple MVC frameworks I see use mod_rewrite (for URL routing) or some other Apache-only method. I run PHP on IIS. I need to be able to understand a basic MVC framework, so that I could develop my own that would allow me to easily extend functionality with classes. I am at the point where I understand basic design patterns and MVC pretty well. I understand them in theory, but when it comes down to actually building a real world, simple, well designed MVC framework in PHP, i'm stuck. I would really appreciate some help! Edit: I just want to note that I am looking for a simple example that an experienced programmer could whip up in under an hour. I mean simple as in bare bones simple. I dont want to use any huge frameworks, I am trying to roll my own. I need a decent SIMPLE example to get me going.

  Read the article

• Autodetect Presence of CSV Headers in a File

  - by banzaimonkey

  Short question: How do I automatically detect whether a CSV file has headers in the first row? Details: I've written a small CSV parsing engine that places the data into an object that I can access as (approximately) an in-memory database. The original code was written to parse third-party CSV with a predictable format, but I'd like to be able to use this code more generally. I'm trying to figure out a reliable way to automatically detect the presence of CSV headers, so the script can decide whether to use the first row of the CSV file as keys / column names or start parsing data immediately. Since all I need is a boolean test, I could easily specify an argument after inspecting the CSV file myself, but I'd rather not have to (go go automation). I imagine I'd have to parse the first 3 to ? rows of the CSV file and look for a pattern of some sort to compare against the headers. I'm having nightmares of three particularly bad cases in which: The headers include numeric data for some reason The first few rows (or large portions of the CSV) are null There headers and data look too similar to tell them apart If I can get a "best guess" and have the parser fail with an error or spit out a warning if it can't decide, that's OK. If this is something that's going to be tremendously expensive in terms of time or computation (and take more time than it's supposed to save me) I'll happily scrap the idea and go back to working on "important things". I'm working with PHP, but this strikes me as more of an algorithmic / computational question than something that's implementation-specific. If there's a simple algorithm I can use, great. If you can point me to some relevant theory / discussion, that'd be great, too. If there's a giant library that does natural language processing or 300 different kinds of parsing, I'm not interested.

  Read the article

• need help passing multiple variables from foreach loop to test in switch case statement

  - by Brad

  $list_of_groups = array("FACULTY","STAFF"); foreach ($list_of_groups as $i => $group) { $user_in_group = $adldap->user_ingroup($username,$group); print "<h2>Group: ".$group." user in group? ".$user_in_group."</h2>"; // if 1, means yes } Need to print run the appropriate function based on what returns true. There are user's that are members of both FACULTY and STAFF groups, so I want to check for those users and display the appropriate content for them. So if the user is both faculty and staff, then display this, if they are only of staff, display that, same for faculty, might not make sense, but I will write out some code "in theory" that will help you understand what I am trying to do switch(Get group membership of user) { case "FACULTY": print "Faculty group member"; break; case "STAFF": print "Staff group member"; break; case "FACULTY and STAFF": print "Member of both faculty and staff"; break; } I am unsure on how it will check if they are members of both groups and run that thru the case statement to display the appropriate message. The foreach look currently runs thru every group the user belongs to, prints out the ones from the $list_of_groups and the number 1 to the right of it, signifying they belong to it. The problem I have is trying to use that information to run thru the case statement, I am unsure of how to go about that. This is what it prints out for the user currently passed thru the foreach loop: Group: FACULTY user in group? 1 Group: STAFF user in group? 1 Any help is appreciated.

  Read the article

• CSS sliding-door buttons center alignment

  - by rochal

  Hi guys, I need help to align CSS buttons. I tried many different variations and I just cannot center my button the way I want. Firstly, have a look at this url: http://www.front-end-developer.net/cssbuttons/example.htm I'm using 2 images to form a button (this could be done on 1 image, but in this case we've got two). Everything works as expected as long as we apply float:left or float:right to the parent div element, to 'limit' width of the div and close it as soon as the content of the div ends. You can remove float:left from the button to see what I mean. But what about center positioned buttons? I cannot add float:left/right because I want align it in the middle. In theory, I could set { width:XXpx; margin:0 auto; } And I will get what you can see on this picture: But I don't know the length of the text inside. Having different translations my button can be very short, or 5 times that long. I also tried to use <span> instead of <div>, but unfortunately nested inline elements don't respect their padding correctly... And yes, I must use <a> inside, so buttons can be accessed by web crawlers. I'm really stuck on this one.

  Read the article

• My PreferenceActivity does not show up, even though it is in my manifest file

  - by Charlie

  So I am modifying the Cube live wallpaper example. I have a class that extends PreferenceActivity, and I added the Activity in my manifest file. I keep getting ActivityNotFoundExceptions. Here is my preference class : public class MySettingsActivity extends PreferenceActivity implements SharedPreferences.OnSharedPreferenceChangeListener { @Override protected void onCreate(Bundle bundle) { super.onCreate(bundle); getPreferenceManager().setSharedPreferencesName( ParticleCandy.SHARED_PREFS_NAME); addPreferencesFromResource(R.xml.settings); getPreferenceManager().getSharedPreferences().registerOnSharedPreferenceChangeListener( this); } @Override protected void onResume() { super.onResume(); } @Override protected void onDestroy() { getPreferenceManager().getSharedPreferences().unregisterOnSharedPreferenceChangeListener( this); super.onDestroy(); } public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) { } } And here is my manifest file <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.pixel.theory.wallpapers.mywallpaper" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <service android:label="@string/app_name" android:name="MyWallpaper" android:permission="android.permission.BIND_WALLPAPER" > <intent-filter> <action android:name="android.service.wallpaper.WallpaperService"> </action> </application> <uses-sdk android:minSdkVersion="7" /> <uses-feature android:name="android.software.live_wallpaper" /> </manifest> Any ideas why my preferences activity doesn't get read in from the manifest?

  Read the article

• how to queue function behind ajax request

  - by user1052335

  What I'm asking is conceptual rather than why my code doesn't work. I'm trying to make a web app that displays content fetched from a database in a sequence, one at a time, and then waits for a response from the user before continuing to the next one. I'm working with javascript on the client side with the JQuery library and php on the server side. In theory, there's time while waiting for the user's input to fetch information from the server using an AJAX request and have it ready for the use by the time he clicks the button, but there's also a chance that such an AJAX request hasn't completed when he clicks the button. So I need something like pseudocode: display current information fetch next data point from the server in the background onUserInput { if ( ajax request complete) { present the information fetched in this request } else if (ajax request not complete) { wait for ajax request complete present information to user } My question is this: how does one implement this " else if (ajax request not complete) { wait for ajax request complete " part. I'm currently using JQuery for my AJAX needs. I'm somewhat new to working with AJAX, and I did search around, but I didn't find anything that seemed on point. I don't know what tools I should use for this. Some kind of queue maybe? I don't need to be spoon fed. I just need to know how this is done, using what tools or if my desired outcome would be accomplished in some other way entirely. Thanks.

  Read the article

• thread reaches end but isn't removed

  - by pstanton

  I create a bunch of threads to do some processing: new Thread("upd-" + id){ @Override public void run(){ try{ doSomething(); } catch (Throwable e){ LOG.error("error", e); } finally{ LOG.debug("thread death"); } } }.start(); I know i should be using a threadPool but i need to understand the following problem before i change it: I'm using eclipse's debugger and looking at the threads in the debug pane which lists active threads. Many of them complete as you would expect, and are removed from the debug pane, however some seem to stay in the list of active threads even though the log shows the "thread death" entry for these. When i attempt to debug these threads, they either do not pause for debugging or show an error dialog: "A timeout occurred while retrieving stack frames for thread: upd-...". there is some synchronization going on within the doSomething() call but i'm fairly sure it's ok and since the "thread death" log is being called i'm assuming these threads aren't deadlocked in that method. i don't do any Thread.join()s, however i do call a third party API but doubt they do either. Can anyone think of another reason these threads are lingering? Thanks. EDIT: I created this test to check the Garbage Collection theory: Thread thread = new Thread("!!!!!!!!!!!!!!!!") { @Override public void run() { System.out.println("running"); ThreadUs.sleepQuiet(5000); System.out.println("finished"); // <-- thread removed from list here } }; thread.start(); ThreadUs.sleepQuiet(10000); System.out.println(thread.isAlive()); // <-- thread already removed from list but hasn't been GC'd ThreadUs.sleepQuiet(10000); this proves that it is nothing to do with garbage collection as eclipse removes the thread from the thread list as soon as it completes and isn't waiting for the object to be de-referenced/GC'd.

  Read the article

• GRAPH PROBLEM: find an algorithm to determine the shortest path from one point to another in a recta

  - by newba

  I'm getting such an headache trying to elaborate an appropriate algorithm to go from a START position to a EXIT position in a maze. For what is worth, the maze is rectangular, maxsize 500x500 and, in theory, is resolvable by DFS with some branch and bound techniques ... 10 3 4 7 6 3 3 1 2 2 1 0 2 2 2 4 2 2 5 2 2 1 3 0 2 2 2 2 1 3 3 4 2 3 4 4 3 1 1 3 1 2 2 4 2 2 1 Output: 5 1 4 2 Explanation: Our agent looses energy every time he gives a step and he can only move UP, DOWN, LEFT and RIGHT. Also, if the agent arrives with a remaining energy of zero or less, he dies, so we print something like "Impossible". So, in the input 10 is the initial agent's energy, 3 4 is the START position (i.e. column 3, line 4) and we have a maze 7x6. Think this as a kind of labyrinth, in which I want to find the exit that gives the agent a better remaining energy (shortest path). In case there are paths which lead to the same remaining energy, we choose the one which has the small number of steps, of course. I need to know if a DFS to a maze 500x500 in the worst case is feasible with these limitations and how to do it, storing the remaining energy in each step and the number of steps taken so far. The output means the agent arrived with remaining energy= 5 to the exit pos 1 4 in 2 steps. If we look carefully, in this maze it's also possible to exit at pos 3 1 (column 3, row 1) with the same energy but with 3 steps, so we choose the better one. With these in mind, can someone help me some code or pseudo-code? I have troubles working this around with a 2D array and how to store the remaining energy, the path (or number of steps taken)....

  Read the article

• What is the correct way to implement a massive hierarchical, geographical search for news?

  - by Philip Brocoum

  The company I work for is in the business of sending press releases. We want to make it possible for interested parties to search for press releases based on a number of criteria, the most important being location. For example, someone might search for all news sent to New York City, Massachusetts, or ZIP code 89134, sent from a governmental institution, under the topic of "traffic". Or whatever. The problem is, we've sent, literally, hundreds of thousands of press releases. Searching is slow and complex. For example, a press release sent to Queens, NY should show up in the search I mentioned above even though it wasn't specifically sent to New York City, because Queens is a subset of New York City. We may also want to implement "and" and "or" and negation and text search to the query to create complex searches. These searches also have to be fast enough to function as dynamic RSS feeds. I really don't know anything about search theory, or how it's properly done. The way we are getting by right now is using a data mart to store the locations the releases were sent to in a single table. However, because of the subset thing mentioned above, the data mart is gigantic with millions of rows. And we haven't even implemented cities yet, and there are about 50,000 cities in the United States, which will exponentially increase the size of the data mart by so much I'm afraid it just won't work anymore. Anyway, I realize this is not a simple question and there won't be a "do this" answer. However, I'm hoping one of you can point me in the right direction where I can learn about how massive searches are done? Because I really know nothing about it. And such a search engine is turning out to be incredibly difficult to make. Thanks! I know there must be a way because if Google can search the entire internet we must be able to search our own database :-)

  Read the article

< Previous Page | 105 106 107 108 109 110 111 112 113 114 115 116  | Next Page >