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  • How to combine two rows and calculate the time difference between two timestamp values in MySQL?

    - by Nadar
    I have a situation that I'm sure is quite common and it's really bothering me that I can't figure out how to do it or what to search for to find a relevant example/solution. I'm relatively new to MySQL (have been using MSSQL and PostgreSQL earlier) and every approach I can think of is blocked by some feature lacking in MySQL. I have a "log" table that simply lists many different events with their timestamp (stored as datetime type). There's lots of data and columns in the table not relevant to this problem, so lets say we have a simple table like this: CREATE TABLE log ( id INT NOT NULL AUTO_INCREMENT, name VARCHAR(16), ts DATETIME NOT NULL, eventtype VARCHAR(25), PRIMARY KEY (id) ) Let's say that some rows have an eventtype = 'start' and others have an eventtype = 'stop'. What I want to do is to somehow couple each "startrow" with each "stoprow" and find the time difference between the two (and then sum the durations per each name, but that's not where the problem lies). Each "start" event should have a corresponding "stop" event occuring at some stage later then the "start" event, but because of problems/bugs/crashed with the data collector it could be that some are missing. In that case I would like to disregard the event without a "partner". That means that given the data: foo, 2010-06-10 19:45, start foo, 2010-06-10 19:47, start foo, 2010-06-10 20:13, stop ..I would like to just disregard the 19:45 start event and not just get two result rows both using the 20:13 stop event as the stop time. I've tried to join the table with itself in different ways, but the key problems for me seems to be to find a way to correctly identify the corresponding "stop" event to the "start" event for the given "name". The problem is exactly the same as you would have if you had table with employees stamping in and out of work and wanted to find out how much they actually were at work. I'm sure there must be well known solutions to this, but I can't seem to find them...

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  • Worpress WorkFlow Modfications

    - by blgnklc
    Hi All WordPress Lovers, I would like to ask a help about Zensor which is a plugin that you publish a post then a moderator approves the post to be published on the wordpress blog site. When a post is awating for approval, each awaiting post is appearing "waiting moderation". But, I dont want any link appears before moderator approval. Actually I found the joing sentence below; 1- Must be added to the end of JOIN part of any query: LEFT JOIN wp_zensor ON ID = wp_zensor.post_id 2- Must be added to the end of WHERE condition : AND wp_zensor.moderation_status = 'approved' Could you please show me; where should I add these modification on the category link presentation below: <h2>Politics</h2> <?php $recent = new WP_Query("cat=31&showposts=1"); while($recent->have_posts()) : $recent->the_post();?> <b><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></b> <?php the_content_limit(140, "devami &raquo;"); ?> <div class="hppostmeta"> <p><?php the_time('j F Y, H:i'); ?> | <?php the_author_posts_link(); ?></p> </div> <?php endwhile; ?> Or any general solutions will be welcomed. Thanks. BK

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  • Configuration Error , Finding assembly after I swapped referenced dll out. Visual Studio 2003

    - by TampaRich
    Here is the situation. I had a clean build of my asp.net web application working. I then went into the bin folder under the web app and replaced two referenced dll's with two older version of the same dll's. (Same name etc.) After testing I replaced those dll's back to the new ones and now my application keeps throwing the configuration error === Pre-bind state information === LOG: DisplayName = xxxxx.xxxx.Personalization (Partial) LOG: Appbase = file:///c:/inetpub/wwwroot/appname LOG: Initial PrivatePath = bin Calling assembly : (Unknown). LOG: Policy not being applied to reference at this time (private, custom, partial, or location-based assembly bind). I found this issue on the web and tried all the solutions to it but nothing worked. I then went into all my projects that it references under the solution and cleared out the bin/debug folder in each, I cleared out the obj folder under each and also deleted the temporary files associated with the application. I rebuilt it and it still will not work due to this error Not sure what is causing this or how to fix this issue. I have tried restarting IIS, stopping index services which was said to be a known issue. This is .net framework 1.1 app and visual studio 2003 Any suggestions would be great. Thanks.

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  • HTTP 401.3 when PUT, DELETE to ADO.NET Data Service (.svc)

    - by Nate
    I have an ADO.NET Data Service (we'll call it service.svc). When I deploy it to an IIS 6 site with Integrated Windows Authentication turned on, all requests (GET, POST, PUT, and DELETE) work fine for me, because I am an administrator on the box. However, when a non-admin user hits the service, only GET and POST requests work. When they try a PUT or DELETE request, they get an HTTP 401.3 "Access is Denied" error: "Error message 401.3: You do not have permission to view this directory or page using the credentials you supplied (access denied due to Access Control Lists). Ask the web server's administrator to give you access to '...\service.svc'." If I give the "Authenticated Users" local group write access to the .svc file, everything works as it should, but I really don't want to do this (and don't think I should have to do this to get this to work). In fact, I'm confused as to why changing the file permissions would affect this at all, but it definitely seems to be the problem. I've found a couple of different suggestions to fix somewhat similar problems in the Microsoft forums (Here, and I would post more links, but am being told that new users can only post one link in a post), but none of the solutions help. Any help is much appreciated. I am certainly no IIS expert, and this one has got me stumped.

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  • Cross domain iframe content load detection

    - by fpb
    I have a rather interesting problem. I have a parent page that will create a modal jquery dialog with an iframe contained within the dialog. The iframe will be populated with content from a 3rd party domain. My issue is that I need to create some dialog level javascript that can detect if the content of the iframe loaded successfully and if it hasn't within a 5 second time frame, then to close the dialog and return the user to the parent page. I have researched numerous solutions and only two are of any true value. Get the remote site to include a javascript line of document.domain = 'our-domain.com'. Use a URL Fragment hack, but again I would need the request that the remote site able to modify the URL by appending '#some_value' to the end of the URL and my dialog window would have to poll the URL until it either sees it or times out. Are these honestly the only options I have to work with? Is there not a simpler way to just detect this? I have been researching if there's a way to poll for http response errors, but this still remains confined to the same restrictions. Any help would be immensely appreciated. Thanks

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  • R Random Data Sets within loops

    - by jugossery
    Here is what I want to do: I have a time series data frame with let us say 100 time-series of length 600 - each in one column of the data frame. I want to pick up 4 of the time-series randomly and then assign them random weights that sum up to one (ie 0.1, 0.5, 0.3, 0.1). Using those I want to compute the mean of the sum of the 4 weighted time series variables (e.g. convex combination). I want to do this let us say 100k times and store each result in the form ts1.name, ts2.name, ts3.name, ts4.name, weight1, weight2, weight3, weight4, mean so that I get a 9*100k df. I tried some things already but R is very bad with loops and I know vector oriented solutions are better because of R design. Thanks Here is what I did and I know it is horrible The df is in the form v1,v2,v2.....v100 1,5,6,.......9 2,4,6,.......10 3,5,8,.......6 2,2,8,.......2 etc e=NULL for (x in 1:100000) { s=sample(1:100,4)#pick 4 variables randomly a=sample(seq(0,1,0.01),1) b=sample(seq(0,1-a,0.01),1) c=sample(seq(0,(1-a-b),0.01),1) d=1-a-b-c e=c(a,b,c,d)#4 random weights average=mean(timeseries.df[,s]%*%t(e)) e=rbind(e,s,average)#in the end i get the 9*100k df } The procedure runs way to slow. EDIT: Thanks for the help i had,i am not used to think R and i am not very used to translate every problem into a matrix algebra equation which is what you need in R. Then the problem becomes a little bit complex if i want to calculate the standard deviation. i need the covariance matrix and i am not sure i can if/how i can pick random elements for each sample from the original timeseries.df covariance matrix then compute the sample variance (t(sampleweights)%*%sample_cov.mat%*%sampleweights) to get in the end the ts.weighted_standard_dev matrix Last question what is the best way to proceed if i want to bootstrap the original df x times and then apply the same computations to test the robustness of my datas thanks

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  • SVN Version Rollback Question

    - by phimuemue
    Hello, I'm using SVN (TortoiseSVN) and often came into the following situation: I wanted to discard any changes since a specific (old) revision and turn all files back to this specific (old) version. Then I wanted to work further as if this specific (old) revision was the newest one, i.e. I wanted to be able to commit the specific old revision as a new revision. I found several solutions for this problem (for example stackoverflow.com/questions/402159/roll-back-or-revert-entire-svn-repository-to-an-older-revision or rustyrazorblade.com/2007/04/how-to-roll-back-commits-to-an-earlier-version-of-a-repository-in-svn/). However, I wonder if there is a simple way to roll back to a specific revision. I thought version control is just good for such things (or am I misunderstanding something?). Is there a simple command/button/etc. that takes an updates my local repository to an old revision and declares it to be the newest one? Since I suppose that there is no "built-in" function to do this, I wanted to know what reason lead the developers to the decision not to integrate this feature. Does anybody know this?

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  • Generate regular expression to match strings from the list A, but not from list B

    - by Vlad
    I have two lists of strings ListA and ListB. I need to generate a regular expression that will match all strings in ListA and will not match any string in ListB. The strings could contain any combination of characters, numbers and punctuation. If a string appears on ListA it is guaranteed that it will not be in the ListB. If a string is not in either of these two lists I don't care what the result of the matching should be. The lists typically contain thousands of strings, and strings are fairly similar to each other. I know the trivial answer to this question, which is just generate a regular expression of the form (Str1)|(Str2)|(Str3) where StrN is the string from ListA. But I am looking for a more efficient way to do this. Ideal solution would be some sort of tool that will take two lists and generate a Java regular expression for this. Update 1: By "efficient", I mean to generate expression that is shorter than trivial solution. The ideal algorithm would generate the shorted possible expression. Here are some examples. ListA = { C10 , C15, C195 } ListB = { Bob, Billy } The ideal expression would be /^C1.+$/ Another example, note the third element of ListB ListA = { C10 , C15, C195 } ListB = { Bob, Billy, C25 } The ideal expression is /^C[^2]{1}.+$/ The last example ListA = { A , D ,E , F , H } ListB = { B , C , G , I } The ideal expression is the same as trivial solution which is /^(A|D|E|F|H)$/ Also, I am not looking for the ideal solution, anything better than trivial would help. I was thinking along the lines of generating the list of trivial solutions, and then try to merge the common substrings while watching that we don't wander into ListB territory. *Update 2: I am not particularly worried about the time it takes to generate the RegEx, anything under 10 minutes on the modern machine is acceptable

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  • How do you get the solution directory in C# (VS 2008) in code?

    - by IsaacB
    Hi, Got an annoying problem here. I've got an NHibernate/Forms application I'm working through SVN. I made some of my own controls, but when I drag and drop those (or view some form editors where I have already dragged and dropped) onto some of my other controls, Visual studio decides it needs to execute some of the code I wrote, including the part that looks for hibernate.cfg.xml. I have no idea why this is, but (sometimes!) when it executes the code during my form load or drag and drop it switches the current directory to C:\program files\vs 9.0\common7\ide, and then nhibernate throws an exception that it can't find hibernate.cfg.xml, because I'm searching for that in a relative path. Now, I don't want to hard code the location of hibernate.cfg.xml, or just copy hibernate.cfg.xml to the ide directory (which will work). I want a solution that gets the solutions directory while the current directory is common7\ide. Something that will let someone view my forms in the designer on a fresh checkout to an arbitrary directory on an arbitrary machine. And no, I'm not about to load the controls in code. I have so many controls within controls that it is a nightmare to line everything up without it. I tried a pre build event that made a file that has the solution directory in it, but of course how can I find that from common7\ide? All the projects files need to be in the solution directory because of svn. Thanks for your help guys, I've already spent a few hours fiddling with this in vain.

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  • ASP.NET - Google Chrome caching DropDownList selections

    - by Fake
    I'm experiencing what seems to be a caching issue with Google Chrome and Safari on my cart page. In the cart there are 2 dropdown lists. When you hit the checkout button after changing the values in the dropdown lists, it commits what's selected in the lists to the database. It's a little bit hard to explain the unexpected behavior so I will try to write it out step by step with an illustration of my problem. Lets say the first dropdown list has the values of: VALUE1 VALUE2 VALUE3 And the second dropdown list has the values of: DUMBO1 DUMBO2 DUMBO3 I add an item to my cart. Screen Says: VALUE1, DUMBO1 Database Says: VALUE1, DUMBO1 I hit Checkout. Database says: VALUE1, DUMBO1 (I can't see the dropdown lists after I hit checkout because i'm not at the cart page) I hit the back button. Screen Says: VALUE1, DUMBO1 Database Says: VALUE1, DUMBO1 I drop down the VALUE1 combo and select VALUE2, VALUE2 is selected momentarily and then the site posts back and VALUE1 is re-selected in the drop down list (from being reloaded from the DB) MOMENTARILY Screen Says: VALUE2, DUMBO1 Database Says: VALUE1, DUMBO1 THEN AFTER POSTBACK FROM DROPDOWNLIST_SELECTIONCHANGED EVENT Screen Says: VALUE1, DUMBO1 Database Says: VALUE1, DUMBO1 Hit Checkout. Database Says VALUE1 ,DUMBO1 (I can't see the dropdown lists after I hit checkout because i'm not at the cart page) Go back. Screen Says: VALUE2, DUMBO1 Database Says: VALUE1, DUMBO1 So it appears that it's remembering my selection of VALUE2 even though it jumped back to VALUE1 before I checked out. It seems to be a caching problem, however I've got some no-cache code to prevent caching of that page that works great in firefox and internet explorer but seems to be failing in Chrome and Safari. I'm basically returning in the headers for the cart page: no-cache, no-store, and must-revalidate to attempt to prevent caching, but based on this scenario it seems to be caching the page anyway and not reloading it when I hit the back button. I am open to any solutions or suggestions at this point. Thanks!

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  • Read header data from files on remote server

    - by rejeep
    Hi! I'm working on a project right now where I need to read header data from files on remote servers. I'm talking about many and large files so I cant read whole files, but just the header data I need. The only solution I have is to mount the remote server with fuse and then read the header from the files as if they where on my local computer. I've tried it and it works. But it has some drawbacks. Specially with FTP: Really slow (FTP is compared to SSH with curlftpfs). From same server, with SSH 90 files was read in 18 seconds. And with FTP 10 files in 39 seconds. Not dependable. Sometimes the mountpoint will not be unmounted. If the server is active and a passive mounting is done. That mountpoint and the parent folder gets locked in about 3 minutes. Does timeout, even when there's data transfer going (guess this is the FTP-protocol and not curlftpfs). Fuse is a solution, but I don't like it very much because I don't feel that I can trust it. So my question is basically if there's any other solutions to the problem. Language is preferably Ruby, but any other will work if Ruby does not support the solution. Thanks!

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  • Reversing strings in a vector using for_each and bind

    - by fmuecke
    Hi! I was wandering how it's possible to reverese strings that are contained in a vector using a single for_each command just in one "simple" line. Yea, I know it is easy with a custom functor, but I can't accept, that it can't be done using bind (at least I couldn't do it). #include <vector> #include <string> #include <algorithm> std::vector<std::string> v; v.push_back("abc"); v.push_back("12345"); std::for_each(v.begin(), v.end(), /*call std::reverse for each element*/); Edit: Thanks a lot for those funtastic solutions. However, the solution for me was not to use the tr1::bind that comes with the Visual Studio 2008 feature pack/SP1. I don't know why it does not work like expected but that's the way it is (even MS admits that it's buggy). Maybe some hotfixes will help. With boost::bind everything works like desired and is so easy (but sometimes relly messy:)). I really should have tried boost::bind in the first place...

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  • Two references to the same domain/entity model

    - by Sbossb
    Problem I want to save the attributes of a model that have changed when a user edits them. Here's what I want to do ... Retrieve edited view model Get domain model and map back updated value Call the update method on repository Get the "old" domain model and compare values of the fields Store the changed values (in JSON) into a table However I am having trouble with step number 4. It seems that the Entity Framework doesn't want to hit the database again to get the model with the old values. It just returns the same entity I have. Attempted Solutions I have tried using the Find() and the SingleOrDefault() methods, but they just return the model I currently have. Example Code private string ArchiveChanges(T updatedEntity) { //Here is the problem! //oldEntity is the same as updatedEntity T oldEntity = DbSet.SingleOrDefault(x => x.ID == updatedEntity.ID); Dictionary<string, object> changed = new Dictionary<string, object>(); foreach (var propertyInfo in typeof(T).GetProperties()) { var property = typeof(T).GetProperty(propertyInfo.Name); //Get the old value and the new value from the models var newValue = property.GetValue(updatedEntity, null); var oldValue = property.GetValue(oldEntity, null); //Check to see if the values are equal if (!object.Equals(newValue, oldValue)) { //Values have changed ... log it changed.Add(propertyInfo.Name, newValue); } } var ser = new System.Web.Script.Serialization.JavaScriptSerializer(); return ser.Serialize(changed); } public override void Update(T entityToUpdate) { //Do something with this string json = ArchiveChanges(entityToUpdate); entityToUpdate.AuditInfo.Updated = DateTime.Now; entityToUpdate.AuditInfo.UpdatedBy = Thread.CurrentPrincipal.Identity.Name; base.Update(entityToUpdate); }

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  • Framework/service for hosting and managing files

    - by Peteris Caune
    Hi, in a webapp I'm building there is a planned side feature of supporting product illustrations and manuals (so pictures and PDFs), possibly arranged in galleries. As I'd rather not implement from scratch all of the uploading, managing and serving of this content, I'm looking for existing solutions which I could integrate. For example, I'm considering Flickr--users of webapp specify their Flickr username and then use some naming convention to link objects in my webapp with pictures uploaded in their Flickr account. Very little code to write from my side, maybe just some API calls that proxy Flickr APIs, since Flickr would handle picture uploading, organizing them in sets, storing them in cloud and serving them in various sizes etc. One drawback here is that either all of the the pictures are public or I have to deal with interactive Flickr authorization. Also not sure if Flickr would be happy being used in such manner. What other online services or libraries/frameworks I should look at? My webapp is written in Python/Pylons, so Python libraries would be preferred. I'm already using some of Amazon infrastructure, so frontends to Amazon S3 would be cool. For online services, RESTful API would be nice.

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  • How do I center align horizontal <UL> menu?

    - by Steven
    I need to centre align a horizontal menu. I've tried various solutions, including the mix of inline-block / block / center-align etc., but not being successful. Can someone help me please? :) Here is my code: <div class="topmenu-design"> <!-- Top menu content: START --> <ul id="topmenu firstlevel"> <li class="firstli" id="node_id_64"><div><a href="#"><span>Om kampanjen</span></a></div></li> <li id="node_id_65"><div><a href="#"><span>Fakta om inneklima</span></a></div></li> <li class="lastli" id="node_id_66"><div><a href="#"><span>Statistikk</span></a></div></li> </ul> <!-- Top menu content: END --> </div> UPDATE I know how to center align the UL within the DIV. That can be accomplished using Sarfraz's suggestion. But the list items are still floated left within the UL. Do I smell javascript to accomplish this?

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  • C++ - Where to throw exception?

    - by HardCoder1986
    Hello! I have some kind of an ideological question, so: Suppose I have some templated function template <typename Stream> void Foo(Stream& stream, Object& object) { ... } which does something with this object and the stream (for example, serializes that object to the stream or something like that). Let's say I also add some plain wrappers like (and let's say the number of these wrappers equals 2 or 3): void FooToFile(const std::string& filename, Object& object) { std::ifstream stream(filename.c_str()); Foo(stream, object); } So, my question is: Where in this case (ideologically) should I throw the exception if my stream is bad? Should I do this in each wrapper or just move that check to my Foo, so that it's body would look like if (!foo.good()) throw (something); // Perform ordinary actions I understand that this may be not the most important part of coding and these solutions are actually equal, but I just wan't to know "the proper" way to implement this. Thank you.

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  • Move and rename file in android

    - by Andre Fróes
    I am trying to copy a file to another folder in the android, but so far, i got no success. I manage to do so with a selected image and when taking a photo, but not with files. I've read and tried several solutions passed by the community (searched over the forum and the internet), but none of it was able to solve my problem when copying. First things first. I added the permissions to my manifest: <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" /> after that, before copying a file, i print its filepath and the directory file path: 06-10 11:11:11.700: I/System.out(1442): /mimetype/storage/sdcard/Misc/Javascript erros for Submit and Plan buttons in IE.doc 06-10 11:11:11.710: I/System.out(1442): /storage/sdcard/mywfm/checklist-files both exists: to copy the file to the expected folder I used the FileUtils: try { FileUtils.copyFile(selectedFile, dir); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } The problem is: I get no exception and the file isn't there. I tried this solution either: How to move/rename file from internal app storage to external storage on Android? same thing, no exception, but no file either.

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  • Looking for a book which teaches how to write applications (as opposed to writng code)

    - by rumtscho
    I am not a developer. I have coded for fun and for university projects in several languages, and during an internship, I have written code which is still in use by a department of Fortune Global 500 company. I also have extensive theoretical knowledge of software engineering - process models, architecture, project management, UI construction using Lauesen's virtual windows... you get the picture. But I am not involved with software development in my job. I recently decided to start coding for fun again, and now I have some free days to do it. But this time, I want to do it right. I want to write a real, useful application, install it on my devices and use it myself. Also I want to publish it for others to use, should they want to do so. I am vaguely aware that there is more to writing an application than to writing code. There is stuff like version control software, decision for the right IDE, having a suite of unit tests, producing an installation package - and probably lots of other things I never thought of but which must be taken care of in a proper application, as opposed to a bunch of classes I am running from my IDE. All this is stuff I should know before I start, but I have not learned it. Coding books touch on some of the subjects like IDE choice, but don't go into detail, and are not exhaustive. Theoretical software engineering textbooks are even less helpful. So is there a book which teaches exactly that? I know that I can find information on each of these topics on the Internet, but I'd rather have a systematic book exhaustively listing all the things I should take care of if I want to create a good application, and offering the currently accepted solutions for them. In the best case, it will be language- and platform independent, but if you know of a good book focusing on a specific platform, I would like to know about it too. I know I want a lot, but given how important such knowledge is and how many people need it, surely somebody must have written such a book?

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  • Shouldn't we ignore IE6 and IE7 users?

    - by Sebi
    Lately I created two webpages with a simple CMS for a a small club and a private person (http://foto.roser.li and http://www.ovlu.li/cms). I dont really understand much of HTML/PHP/CSS and all this web stuff, but it was enough to adapt the stylesheets and add some javascript functions and so on to make the pages to look more or less nice in firefox and IE8. Nevertheles, if you open the pages with IE7 or IE6, particulary the second home page really looks terrible. So what should I do know? I don't have the know-how to adapt the stylesheets so that it looks good at such browsers. However if I check the statistics of the pages, i noticed that almost half of the visitors uses this kind of browsers. I could put much effort in adapting the stylesheets to look good at all browser but while thinking about this I'm asking myself if this is really the best way. If all developers put effort in providing solutions for really old browsers (like e.g. the IE6), then people who use these brwoser dont have any incentives to update their browsers. Naturally, I as a provider of information should present the content in a readable form to my users, but were should i draw the line? I also saw that some users are visiting the pages with even IE5 or IE4... but I really can't think of a way how to adapt the content in a suitable form for these very old brwosers. I would appreciaed any hints how to handle this balancing between putting much effort into developing a version for very old brwosers and the necessity of providing content to all users which want to visits my homepages. Im also interested in your thoughts about they idea that putting effort in adapting the content for old browsers prevents the users from updating their browsres because they don't see any need.

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  • is there a simple timed lock algorithm avoiding deadlock on multiple mutexes?

    - by Vicente Botet Escriba
    C++0x thread library or Boost.thread define a non-member variadic template function that locks all mutex at once that helps to avoid deadlock. template <class L1, class L2, class... L3> void lock(L1&, L2&, L3&...); The same can be applied to a non-member variadic template function try_lock_until, which locks all the mutex until a given time is reached that helps to avoid deadlock like lock(...). template <class Clock, class Duration, class L1, class L2, class... L3> void try_lock_until( const chrono::time_point<Clock,Duration>& abs_time, L1&, L2&, L3&...); I have an implementation that follows the same design as the Boost function boost::lock(...). But this is quite complex. As I can be missing something evident I wanted to know if: is there a simple timed lock algorithm avoiding deadlock on multiple mutexes? If no simple implementation exists, can this justify a proposal to Boost? P.S. Please avoid posting complex solutions.

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  • Website badge system

    - by linkyndy
    I am currently working on a widget-based website, built entirely on user socialization. Since a reputation system pays off for attracting users, I decided to implement one of these. Now, I would like to hear some solutions on how should this be implemented the right way (take, for example, Foursquare's badge system). Basically, I need to be able to do the following: have a badges table, where I can add, edit and delete badges; be able to enable and disable a badge; be able to introduce a new badge, but without writing new code - simply give some parameters to the add badge form regarding what should be followed in order for a user to receive a badge; be able to give badges in real time - meaning that whenever a user accomplishes whatever it needs to receive a badge, the system should know immediately to give the badge to that user; also, the system should not be overloaded with "badge listeners" - I believe interrogating each user request with every badge requirements is time consuming; These being said, I would like to hear your opinions on how to implement the right way a badge system (logic, database schema, methods etc.) Thank you very much!

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  • Optimize Duplicate Detection

    - by Dave Jarvis
    Background This is an optimization problem. Oracle Forms XML files have elements such as: <Trigger TriggerName="name" TriggerText="SELECT * FROM DUAL" ... /> Where the TriggerText is arbitrary SQL code. Each SQL statement has been extracted into uniquely named files such as: sql/module=DIAL_ACCESS+trigger=KEY-LISTVAL+filename=d_access.fmb.sql sql/module=REP_PAT_SEEN+trigger=KEY-LISTVAL+filename=rep_pat_seen.fmb.sql I wrote a script to generate a list of exact duplicates using a brute force approach. Problem There are 37,497 files to compare against each other; it takes 8 minutes to compare one file against all the others. Logically, if A = B and A = C, then there is no need to check if B = C. So the problem is: how do you eliminate the redundant comparisons? The script will complete in approximately 208 days. Script Source Code The comparison script is as follows: #!/bin/bash echo Loading directory ... for i in $(find sql/ -type f -name \*.sql); do echo Comparing $i ... for j in $(find sql/ -type f -name \*.sql); do if [ "$i" = "$j" ]; then continue; fi # Case insensitive compare, ignore spaces diff -IEbwBaq $i $j > /dev/null # 0 = no difference (i.e., duplicate code) if [ $? = 0 ]; then echo $i :: $j >> clones.txt fi done done Question How would you optimize the script so that checking for cloned code is a few orders of magnitude faster? System Constraints Using a quad-core CPU with an SSD; trying to avoid using cloud services if possible. The system is a Windows-based machine with Cygwin installed -- algorithms or solutions in other languages are welcome. Thank you!

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  • WPF A good way to make a view/edit control?

    - by Jefim
    Hi, this is just a question to discuss - what is the best way to make a view/edit control in WPF? E.g. we have an entity object Person, that has some props (name, surname, address, phone etc.). One presentation of the control would be a read-only view. And the other would have the edit view for this same person. Example: <UserControl x:Name="MyPersonEditor"> <Grid> <Grid x:Name="ViewGrid" Visibility="Visible"> <TextBlock Text="Name:"/> <TextBlock Text="{Binding Person.Name}"/> <Button Content="Edit" Click="ButtonEditStart_Click"/> </Grid> <Grid x:Name="EditGrid" Visibility="Collapsed"> <TextBlock Text="Name:"/> <TextBox Text="{Binding Person.Name}"/> <Button Content="Save" Click="ButtonEditEnd_Click"/> </Grid> </Grid> </UserControl> I hope that the idea is clear. The two options I see right now two grids with visibility switching and a TabControl without its header panel This is just a discussion question - not much trouble with it, yet I am just wondering if there are any other possibilities and elegant solutions to this.

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  • What kind of online hosting do I need for a WCF-based service?

    - by mafutrct
    First of all, I'm not sure if SO is the right place to ask. Please migrate me if needed. I would like to host a WCF-based service so it is available for everyone. While hosting it on my personal, local servers succeeded, I would prefer to move it to an external service provider for various reasons. I'll be blunt: I have no clue about hosting providers. I know there are webhosters, virtual and root servers and several other services. What I would like to know is what kind of hosting I need in my case. I understand that a root server would easily fulfill my requirements, but that is not exactly cheap. The program I'd like to run on the server requires .NET 4, preferably on a windows machine. Access to a folder in the file system is much appreciated (1 GB storage is enough by far). Communication with clients (in form of an applications written in .NET) via opening a port on the server. Traffic is low (<<1 GB/month?) There is no website. Having the provider perform updates would be nice. My understanding is that a virtual server would be a possible solution. Prices seem start at around 5€/month, which is ok for me. However, I read that for these cheap solutions RAM is severely limited (~400 MB), and I'm not confident that is enough to run windows and a .NET application.

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  • File being used by another process. Reason, and solution?

    - by pstar
    The process cannot access the file 'abc.log' because it is being used by another process. Hi, I've seen this exception from my application occationaly but I am still trying to fix that, hope I will get some insight from stackoverflow. In my application I've have defined a WriteToLog function which will write to a log file. Also the mainForm of my application will launch a backgroundWorker do some job which also calls the WriteToLog. Maybe two threads access a file will cause a problem? But in my code I 've already do my best to write flush and close the text file (I think), and here is my code from WriteToLog: StreamWriter sw = null; string newText = ""; try { //populate the content for newText sw = File.AppendText(LOG_FILE); sw.Write(newText); sw.Flush(); sw.Close(); } catch (IOException ex) { MessageBox.Show("Failed to write to log!\n\t" + ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); } finally { if (sw != null) { sw.Close(); } } I think as long as I flush and close the streamWriter, I should be able call the WriteToLog multi-times and in multi-threads isn't it? Or if I am wrong, could I simple make the file open shared, or there are other reason/solutions?

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