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• Ignore all folders with a certain name in SVN (subversion), how to?

  - by Roeland

  I am fairly new to Subversion and was wondering how exactly to ignore all folders by a specific name. From what I have read, I think I need to use the svn:ignore function, but I have no clue on how to actually do this. Some places mention a config file.. some say command prompt. I have my subversion repo set up on a windows 2008 server. I tried to go to command prompt and type svn:ignore name but that didnt work. The tutorial I used to set up my repo (with apache 2.2) had me create an etc folder in c:/. There I have subversion.conf, svn-acl and svn-auth-file. My subversion.conf file includes this: <Location /btp> DAV svn SVNPath C:/Files/Work/Repositories/btp AuthType Basic AuthName "By The Pixel Repo" AuthUserFile c:/etc/svn-auth-file Require valid-user AuthzSVNAccessFile c:/etc/svn-acl </Location> The client I use for my development machines is tortoisesvn. Im a bit of a noob so any help is appreciated it! Thanks.

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• MSI File/Registry failures on Windows Server 2008/Windows 7 (x64)

  - by Luca

  I'm trying to deploy an application on Windows Server 2008 (SP2 x64) and Windows 7 (x64), using VS2005 Installer Project. The MSI version (I think) it the 2.0. Everything works fine, except that some registry keys and some files are not copied on the install machine. The MSI system doesn't notify about nothing (and I don't know whether MSI logs its operations). Are there incompatibilities between my MSI installer project and these new OSes? It seems to me that the OS protect itself for being modified in some part. For example, I'm trying to set the registry keys: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\WinLogon\SpecialAccounts\UserList\User but it is not created. In the same installer there are many other keys, which are created like expected (as they always did before on Windows XP and Windows Server 2003). To provide another example, I'm trying to install the file %SystemFolder%\oobe\info\backgrounds\backgroundDefault.jpg (where %SystemFolder% is typically "C:\Windows\System32"), but the file is not copied at all!!! What's going on? I've found the backgroundDefault.jpg file is located in another directory: %SystemRoot%\SysWOW64\oobe\info. But I've not specified nothing about a System (64 bit) folder. How can I copy the file in the right place?

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• JQuery UI Sortable

  - by RussP

  Can someone please help me with this one: When using UISortables where - and how do I put "serialize" into the JQuery function? I have 4 columns class '.columm' and each wit a unique id - col1,col2,col3 & col4. I can get the drag & drop bit to work I now need to put the "final" positions into a serialized array. Here is my code: $(".column").sortable({ revert: true, scroll: true, appendTo: 'body', connectWith: '.column', delay:200, stop: function() { $(".column").each(function(){ var test = $(this).attr('id'); alert(test); // //var myArray = $(this).sortable("serialize"); }) }, revertDuration:50000, scope:'scope', opacity: 0.80, }); You will see alert test. I have done this to see if I can get the col id's into an alert and I can, but where do i put .sortable( "serialize" , [options] ) and how do I do that for the 4 columns to create 1 single serialized array? having done that how/where do you set the order when you next load the page? (OK yes, I do intent to "store" the serialized array) Help please - thanks

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• Invalid Pointer Operation, advice requested with debugging

  - by Xanyx

  I appear to have created code that is trashing memory. Having never had such problems before, i am now settign an Invalid Pointer Operation. In the following the value of the const string sFilename gets trashed after my call to PromptForXYZPropertiesSettings. // Allow the user to quickly display the properties of XYZ without needing to display the full Editor function PromptForXYZProperties(const sFilename:string; var AXYZProperties: TXYZProperties): boolean; var PropEditor: TdlgEditor; begin PropEditor:= TdlgEditor.create(nil); try PropEditor.LoadFromFile(sFilename); Other Details: Delphi 2007, Windows 7 64 bit, but can reproduce when testing EXE on XP REMOVING CONST STOPS PROBLEM FROM EXHIBITING (but presumably the problem is thus just lurking) PropEditor.PromptForXYZPropertiesSettings creates and shows a form. If I disable the ShowModal call then the memory is not trashed. Even though i have REMOVED ALL CONTROLS AND CODE from the form So I would like some advice on how to debug the issue. I was thinking perhaps watching the memory pointer where the sFilename var exists to see where it gets trashed, but not sure how i would do that (obviously needs to be done within the app so is owned memory). Thanks

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• How do I setup model associations in an RSpec test?

  - by Eric M.

  I've pastied the specs I've written for the posts/show.html.erb view in an application I'm writing as a means to learn RSpec. I am still learning about mocks and stubbing. This question is specific to the "should list all related comments" spec. What I want is to test that the show view displays a post's comments. But what I'm not sure about is how to setup this test and then have the test iterate through with should contain('xyz') statements. Any hints? Other suggestions are also appreciated! Thanks. ---Edit Some more information. I have a named_scope applied to comments in my view (I know, I did this a bit backwards in this case), so @post.comments.approved_is(true). The code pastied responds with the error "undefined method `approved_is' for #", which makes sense since I told it stub comments and return a comment. I'm still not sure, however, how to chain the stubs so that @post.comments.approved_is(true) will return an array of comments.

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• Is programming overrated?

  - by aengine

  [Subjective and intended to be a community wiki] I am sorry for such an offensive question: But here are my arguments Most of the progress in "computing" has came from non-programming sources. i.e. People invented faster microprocessors and better routers and novel memory devices. I dont think on average people are writting more efficient programs than those written 10 years ago. And the newer and popular languages are infact slower than C. though speed is one of the lesser criterias. Most of the progress came from novel paradigms. Web, Internet, Cloud computing and Social networking are novel paradigms and did not involve progress in programming as such. Heck even facebook was written in PHP and not some extreme language. Though it did face scalability issues (same with twitter) but i believe money and better programmers (who came in much later) took care of that. Thus ideating capability trumped programming capability/ Even things like Map-Reduce, Column oriented database and Probablistic algorithms (E.g. bloom filters) came from hardcore Algorithms research, rather than some programming convention. Thus my final point is why programming skill is so overstressed? To point a recent example about how only 10% of programmers can "write code" (binary search) without debugging. Isnt it a bit hypocritical, considering your real successs lies in coming up with better algorithm or a novel feature rather than getting right first time???

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• Error when feeding a mysql db with a python-parsed data

  - by Barnabe

  I use this bit of code to feed some data i have parsed from a web page to a mysql database c=db.cursor() c.executemany( """INSERT INTO data (SID, Time, Value1, Level1, Value2, Level2, Value3, Level3, Value4, Level4, Value5, Level5, ObsDate) VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)""", clean_data ) The parsed data looks like this (there are several hundred such lines) clean_data = [(161,00:00:00,8.19,1,4.46,4,7.87,4,6.54,null,4.45,6,2010-04-12),(162,00:00:00,7.55,1,9.52,1,1.90,1,4.76,null,0.14,1,2010-04-12),(164,00:00:00,8.01,1,8.09,1,0,null,8.49,null,0.20,2,2010-04-12),(166,00:00:00,8.30,1,4.77,4,10.99,5,9.11,null,0.36,2,2010-04-12)] if i hard code the data as above mySQL accepts my request (except for some quibbles about formatting) but if the variable clean_data is instead defined as the result of the parsing code, like this: cleaner = [(""" $!!'""", ')]'),(' $!!', ') etc etc] def processThis(str,lst): for find, replace in lst: str = str.replace(find, replace) return str clean_data = processThis(data,cleaner) then i get the dreaded "TypeError: not enough arguments for format string" After playing with formatting options for a few hours (I am very new to this) I am confused... what is the difference between the hard coded data and the result of the processThis function as fas as mySQL is concerned? Any idea greatly appreciated...

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• Theme-aware XAML resources in a WP7 project

  - by SandRock

  I'm making a Windows Phone 7 application and I'm a bit confused with dark/light themes. With a panorama, you very often set a background image. The issue is it's very hard to make a picture which is right for both dark and light themes. How are we supposed to proceed? Is there a way to force a dark/light theme for a panorama? This will avoid making theme-specific panorama background pictures. Then how do I do? I found xaml files in C:\Program Files (x86)\Microsoft SDKs\Windows Phone\v7.0\Design. If this is a right way to proceed, how can I import them for my panorama? Or if there's no way (or if it's wrong) to force a dark/light theme: how to write conditional XAML to set correct resources? Now I have the following XAML which is fine with the dark theme: <ImageBrush x:Key="PageBackground" ImageSource="Resources/PageBackground.png" Stretch="None" /> <ImageBrush x:Key="PanoramaBackground" ImageSource="Resources/PanoramaBackground.png" Stretch="None" /> But when I use a light theme, black controls and black texts are hard to read with my dark background pictures. So I made different pictures that I can use this way: <ImageBrush x:Key="PageBackground" ImageSource="Resources/PageBackgroundLight.png" Stretch="None" /> <ImageBrush x:Key="PanoramaBackground" ImageSource="Resources/PanoramaBackgroundLight.png" Stretch="None" /> Now my issue is to make XAML conditionnal to declare the right thing depending on the current theme. I found no relevant way on the Internet. I would prefer not to use code or code-behind for that because I believe XAML is able to do this (I just don't know how).

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• page variable in a repeater

  - by carrot_programmer_3

  Hi I'm having a bit of an issue with a asp.net repeater I'm building a categories carousel with the dynamic categories being output by a repeater. Each item is a LinkButton control that passes an argument of the category id to the onItemClick handler. a page variable is set by this handler to track what the selected category id is.... public String SelectedID { get { object o = this.ViewState["_SelectedID"]; if (o == null) return "-1"; else return (String)o; } set { this.ViewState["_SelectedID"] = value; } } problem is that i cant seem to read this value while iterating through the repeater as follows... <asp:Repeater ID="categoriesCarouselRepeater" runat="server" onitemcommand="categoriesCarouselRepeater_ItemCommand"> <ItemTemplate> <%#Convert.ToInt32(Eval("CategoryID")) == Convert.ToInt32(SelectedID) ? "<div class=\"selectedcategory\">":"<div>"%> <asp:LinkButton ID="LinkButton1" CommandName="select_category" CommandArgument='<%#Eval("CategoryID")%>' runat="server"><img src="<%#Eval("imageSource")%>" alt="category" /><br /> </div> </ItemTemplate> </asp:Repeater> calling <%=SelectedID%> in the item template works but when i try the following expression the value of SelectedID returns empty.. <%#Convert.ToInt32(Eval("CategoryID")) == Convert.ToInt32(SelectedID) ? "match" : "not a match"%> the value is being set as follows... protected void categoriesCarouselRepeater_ItemCommand(object source, RepeaterCommandEventArgs e) { SelectedID = e.CommandArgument); } Any ideas whats wrong here?

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• Bind to a collection's view and just call ToString() in WPF

  - by womp

  I'm binding a GridView to a collection of objects that look like this: public class Transaction { public string PersonName { get; set; } public DateTime TransactionDate { get; set; } public MoneyCollection TransactedMoney { get; set;} } MoneyCollection simply inherits from ObservableCollection<T>, and is a collection of MyMoney type object. In my GridView, I just want to bind a column to the MoneyCollection's ToString() method. However, binding it directly to the TransactedMoney property makes every entry display the text "(Collection)", and the ToString() method is never called. Note that I do not want to bind to the items in MoneyCollection, I want to bind directly to the property itself and just call ToString() on it. I understand that it is binding to the collection's default view. So my question is - how can I make it bind to the collection in such a way that it calls the ToString() method on it? This is my first WPF project, so I know this might be a bit noobish, but pointers would be very welcome.

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• How to get the real, actual duration of an MP3 file (VBR or CBR) server-side

  - by Cummander Checkov

  I used to calculate the duration of MP3 files server-side using ffmpeg - which seemed to work fine. Today i discovered that some of the calculations were wrong. Somehow, for some reason, ffmpeg will miscalculate the duration and it seems to happen with variable bit rate mp3 files only. When testing this locally, i noticed that ffmpeg printed two extra lines in green. Command used: ffmpeg -i song_9747c077aef8.mp3 ffmpeg says: [mp3 @ 0x102052600] max_analyze_duration 5000000 reached at 5015510 [mp3 @ 0x102052600] Estimating duration from bitrate, this may be inaccurate After a nice, warm google session, i found some posts on this, but no solution was found. I then tried to increase the maximum duration: ffmpeg -analyzeduration 999999999 -i song_9747c077aef8.mp3 After this, ffmpeg returned only the second line: [mp3 @ 0x102052600] Estimating duration from bitrate, this may be inaccurate But in either case, the calculated duration was just plain wrong. Comparing it to VLC i noticed that here the duration is correct. After more research i stumbled over mp3info - which i installed and used. mp3info -p "%S" song_9747c077aef8.mp3 mp3info then returned the CORRECT duration, but only as an integer, which i cannot use as i need a more accurate number here. The reason for this was explained in a comment below, by user blahdiblah - mp3info is simply pulling ID3 info from the file and not actually performing any calculations. I also tried using mplayer to retrieve the duration, but just as ffmpeg, mplayer is returning the wrong value. Now i ran out of options. If somebody knows how to get around this, any hints, tips, guides or corrections are welcome! Thank You!

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• Newbie - eclipse workflow (PHP development)

  - by engil

  Hi all - this is a bit of a newbie question but hoping I can get some guidance. I've been playing around with Eclipse for a couple months yet I'm still not completely comfortable with my setup and it seems like every time I install it to a new system I end up with different results. What I'm hoping to achieve is (I think) fairly standard. In my environment I'd like SVN (currently using Subclipse), FTP support (currently using Aptana plugin), debugging (going to use XDebug) and all the usual bells and whistles of development (code completion, refactoring, etc.) My biggest current issue is how to set up my environment to support both a 'development' and 'production' server. Optimally I would be able to work directly against the dev server (Eclipse on my Vista desktop against the VM Ubuntu dev server) and then push to production server (shared hosting). I'd prefer to work directly against the dev server (with no local project files, just using the Connections provided by Aptana) but I'm guessing this won't allow for code-completoin or all the other bells and whistles provided for development. Any thoughts? Kind of an open ended question, but maybe this could be an opportunity for some of you with a great deal of experience using Eclipse to describe your setups so people like me can get some insight into good ways to get set up.

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• CakePHP dropping session between pages

  - by DavidYell

  Hi, I have an application with multiple regions and various incoming links. The premise, well it worked before, is that in the app_controller, I break out these incoming links and set them in the session. So I have a huge beforeFilter() in my *app_controller* which catches these and sets two variables in the session. Viewing.region and Search.engine, no problem. The problem arises that the session does not seem to be persistant across page requests. So for example, going to /reviews/write (userReviews/add) should have a session available which was set when the user arrived at the site. Although it seems to have vanished! It would appear that unless $this-params is caught explicitly in the *app_controller* and a session variable written, it does not exist on other pages. So far I have tried, swapping between storing session in 'cake' and 'php' both seem to exhibit the same behaviour. I use 'php' as a default. My Session.timeout is '120', Session.checkAgent is False and Security.level is 'low'. All of which should give enough leniency to the framework to allow sessions the most room to live! I'm a bit stumped as to why the session seems to be either recreated or blanked when a new page is being requested. I have commented out the requestAction() calls to make sure that isn't confusing the session request object also, which doesn't seem to make a difference. Any help would be great, as I don't have to have to recode the site to pass all the various variables via parameters in the url, as that would suck, and it's worked before, thus switching on $this-Session-read('Viewing.region') in all my code!

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• Inexplicably slow query in MySQL

  - by Brandon M.

  Given this result-set: mysql> EXPLAIN SELECT c.cust_name, SUM(l.line_subtotal) FROM customer c -> JOIN slip s ON s.cust_id = c.cust_id -> JOIN line l ON l.slip_id = s.slip_id -> JOIN vendor v ON v.vend_id = l.vend_id WHERE v.vend_name = 'blahblah' -> GROUP BY c.cust_name -> HAVING SUM(l.line_subtotal) > 49999 -> ORDER BY c.cust_name; +----+-------------+-------+--------+---------------------------------+---------------+---------+----------------------+------+----------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+--------+---------------------------------+---------------+---------+----------------------+------+----------------------------------------------+ | 1 | SIMPLE | v | ref | PRIMARY,idx_vend_name | idx_vend_name | 12 | const | 1 | Using where; Using temporary; Using filesort | | 1 | SIMPLE | l | ref | idx_vend_id | idx_vend_id | 4 | csv_import.v.vend_id | 446 | | | 1 | SIMPLE | s | eq_ref | PRIMARY,idx_cust_id,idx_slip_id | PRIMARY | 4 | csv_import.l.slip_id | 1 | | | 1 | SIMPLE | c | eq_ref | PRIMARY,cIndex | PRIMARY | 4 | csv_import.s.cust_id | 1 | | +----+-------------+-------+--------+---------------------------------+---------------+---------+----------------------+------+----------------------------------------------+ 4 rows in set (0.04 sec) I'm a bit baffled as to why the query referenced by this EXPLAIN statement is still taking about a minute to execute. Isn't it true that this query only has to search through 449 rows? Anyone have any idea as to what could be slowing it down so much?

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• Performance when querying a View

  - by Nate Bross

  I'm wondering if this is a bad practice or if in general this is the correct approach. Lets say that I've created a view that combines a few attributes from a few tables. My question, what do I need to do so I can query against this view as if it were a table without worrying about performance? All attributes in the original tables are indexed, my concern is that the result view will have hundreds of thousands of records, which I will want to narrow down quite a bit based on user input. What I'd like to avoid, is having multiple versions of the code that generates this view floating around with a few extra "where" conditions to facilitate the user input filtering. For example, assume my view has this header VIEW(Name, Type, DateEntered) this may have 100,000+ rows (possibly millions). I'd like to be able to make this view in SQL Server, and then in my application write querlies like this: SELECT Name, Type, DateEntered FROM MyView WHERE DateEntered BETWEEN @date1 and @date2; Basically, I am denormalizing my data for a series of reports that need to be run, and I'd like to centralize where I pull the data from, maybe I'm not looking at this problem from the right angle though, so I'm open to alternative ways to attack this.

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• codeigniter cron job with http access

  - by user1313850

  Sorry if this is a duplicate question...I've searched around and found similar advice but nothing that helps my exact problem. And please excuse the noob questions, CRON is a new thing for me. I have a codeigniter script that scrapes the html DOM of another site and stores some of that in a database. I'd like to run this script at a regular interval. This has lead me to looking into cron jobs. The page I have is at myserver.com/index.php/update I realize I can run a cron job with curl and run this page. If I want to be a bit more secure I can put a string at the end like: myserver.com/index.php/update/asdfh2784fufds And check for that in my CI controller. This seems like it would be mostly secure, but doesn't seem like the "right" way to do things. I've looked into running CI from the command line, and can execute basic pages like: php index.php mycontroller But when I try to do: php index.php update It doesn't work. I suspect this is because it needs to use HTTP to scrape the DOM of the outside page. So, my question: How do I securely run a codeigniter script with a cron job that needs HTTP access?

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• Why is there so much XML in Java these days?

  - by BD at Rivenhill

  This is really more of a philosophy/design issue. I did some work in Java back in the middle 90's and again in the early 2000's and now I'm coming back to it after spending a lot of time in C/C++ and it seems like there was an explosion of XML dependency while I was gone. Major build system tools like ant and maven depend on XML for their configuration, but I'm actually more concerned with all the frameworks, such as Spring, Hibernate, etc. My experience is that powerful supporting libraries like these are where a developer can really get leverage for building programs with lots of features without writing a lot of code, but it really seems like I'm getting one language for the price of two here. I write a bunch of Java classes, but then I also write a bunch of XML files to glue them together. The things that get done in the XML are things that I can see reasonable ways of doing in straight code without the middleman, and they don't really seem to be treated exactly like configuration files: they change rarely and they end up getting committed to source code control like the Java code itself, but they are distributed with the resulting application and need to be unpacked and installed in the classpath in order to get the application to work. I'm working with server applications that are not web-based, so maybe the domain is a bit different from what most people are doing, but I just can't help feeling that I must be doing something wrong here. Can someone point me to a good source of information for why these design choices were made and what problems they are meant to solve so that I can analyze my own experiences in this context?

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• Why is Apache + Rails is spitting out two status headers for code 500?

  - by Daniel Beardsley

  I have a rails app that is working fine except for one thing. When I request something that doesn't exist (i.e. /not_a_controller_or_file.txt) and rails throws a "No Route matches..." exception, the response is this (blank line intentional): HTTP/1.1 200 OK Date: Thu, 02 Oct 2008 10:28:02 GMT Content-Type: text/html Content-Length: 122 Vary: Accept-Encoding Keep-Alive: timeout=15, max=100 Connection: Keep-Alive Status: 500 Internal Server Error Content-Type: text/html <html><body><h1>500 Internal Server Error</h1></body></html> I have the ExceptionLogger plugin in /vendor, though that doesn't seem to be the problem. I haven't added any error handling beyond the custom 500.html in public (though the response doesn't contain that HTML) and I have no idea where this bit of html is coming from. So Something, somewhere is adding that HTTP/1.1 200 status code too early, or the Status: 500 too late. I suspect it's Apache because I get the appropriate HTTP/1.1 500 header (at the top) when I use Webrick. My production stack is as follows: Apache 2 Mongrel (5 instances) RubyOnRails 2.1.1 (happens in both 1.2 and 2.1.1) I forgot to mention, the error is caused by a "no route matches..." exception

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• Database/Object Mapping

  - by Eric

  Hello everyone, This is a beginner question, but it's been frustrating me... I am using C#, by the way. I'd like to make a few classes, each with their own properties and methods. I would also like to have a database to store certain instances of these classes in case I would ever need to look at them again. So, for example... class Polygon { String name; Double perimiter; int numSides; public Double GetArea() { // ... } } class Circle { String name; Double radius; public void PrintName() { // ... } } Say I've got these classes. I also want a database that has the TABLES "Polygon" and "Circle" with the COLUMNS "name" "perimeter" "radius" etc. And I want an easy way to save a class instance into the database, or pull a class instance out of the database. I have previously been using MS Access for my database stuff, which I don't mind using, but I would prefer if nothing other than .NET need to be installed. I've been researching online a bit, but I wanted to get some opinions on here. I have looked at Linq-to-Sql, but it seems you need Sql-Server. Is this true? If so, I'd really rather not use it because I don't want to have to have it installed everywhere. Anway, I'm just fishing for some ideas/insights/suggestions/etc. so please help me out if you can. Thanks.

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• Caching vector addition over changing collections

  - by DRMacIver

  I have the following setup: I have a largish number of uuids (currently about 10k but expected to grow unboundedly - they're user IDs) and a function f : id - sparse vector with 32-bit integer values (no need to worry about precision). The function is reasonably expensive (not outrageously so, but probably on the order of a few 100ms for a given id). The dimension of the sparse vectors should be assumed to be infinite, as new dimensions can appear over time, but in practice is unlikely to ever exceed about 20k (and individual results of f are unlikely to have more than a few hundred non-zero values). I want to support the following operations efficiently: add a new ID to the collection invalidate an existing ID retrieve sum f(id) in O(changes since last retrieval) i.e. I want to cache the sum of the vectors in a way that's reasonable to do incrementally. One option would be to support a remove ID operation and treat invalidation as a remove followed by an add. The problem with this is that it requires us to keep track of all the old values of f, which is expensive in space. I potentially need to use many instances of this sort of cached structure, so I would like to avoid that. The likely usage pattern is that new IDs are added at a fairly continuous rate and are frequently invalidated at first. Ids which have been invalidated recently are much more likely to be invalidated again than ones which have remained valid for a long time, but in principle an old Id can still be invalidated. Ideally I don't want to do this in memory (or at least I want a way that lets me save the result to disk efficiently), so an idea which lets me piggyback off an existing DB implementation of some sort would be especially appreciated.

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• Why can't we just use a hash of passphrase as the encryption key (and IV) with symmetric encryption algorithms?

  - by TX_

  Inspired by my previous question, now I have a very interesting idea: Do you really ever need to use Rfc2898DeriveBytes or similar classes to "securely derive" the encryption key and initialization vector from the passphrase string, or will just a simple hash of that string work equally well as a key/IV, when encrypting the data with symmetric algorithm (e.g. AES, DES, etc.)? I see tons of AES encryption code snippets, where Rfc2898DeriveBytes class is used to derive the encryption key and initialization vector (IV) from the password string. It is assumed that one should use a random salt and a shitload of iterations to derive secure enough key/IV for the encryption. While deriving bytes from password string using this method is quite useful in some scenarios, I think that's not applicable when encrypting data with symmetric algorithms! Here is why: using salt makes sense when there is a possibility to build precalculated rainbow tables, and when attacker gets his hands on hash he looks up the original password as a result. But... with symmetric data encryption, I think this is not required, as the hash of password string, or the encryption key, is never stored anywhere. So, if we just get the SHA1 hash of password, and use it as the encryption key/IV, isn't that going to be equally secure? What is the purpose of using Rfc2898DeriveBytes class to generate key/IV from password string (which is a very very performance-intensive operation), when we could just use a SHA1 (or any other) hash of that password? Hash would result in random bit distribution in a key (as opposed to using string bytes directly). And attacker would have to brute-force the whole range of key (e.g. if key length is 256bit he would have to try 2^256 combinations) anyway. So either I'm wrong in a dangerous way, or all those samples of AES encryption (including many upvoted answers here at SO), etc. that use Rfc2898DeriveBytes method to generate encryption key and IV are just wrong.

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• Replacing characters in a non well-formed XML body

  - by ryanprayogo

  In a (Java) code that I'm working on, I sometimes deal with a non well-formed XML (represented as a Java String), such as: <root> <foo> bar & baz < quux </foo> </root> Since this XML will eventually need to be unmarshalled (using JAXB), obviously this XML as is will throw exception upon unmarshalling. What's the best way to replace the & and the < to its character entities? For &, it's as easy as: xml.replaceAll("&", "&amp;") However, for the < symbol, it's a bit tricky since obviously I don't want to replace the < that's used for the XML tag opening 'bracket'. Other than scanning the string and manually replacing < in the XML body with &lt;, what other option can you suggest?

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• What do you call a generalized (non-GUI-related) "Model-View-Controller" architecture?

  - by dcuccia

  I am currently refactoring code that coordinates multiple hardware components for data acquisition, and feeling a bit like I'm recreating the wheel. In particular, an MVC-like pattern seems to be emerging. Except, this has nothing to do with a GUI and I'm worried that I'm forcing this particular pattern where another might be more appropriate. Here's my scenario: Individual hardware "component" classes obey interface contracts for each hardware type. Previously, component instances were orchestrated by a single monolithic InstrumentController class, which relied heavily on configuration + branching logic for executing a specific acquisition sequence. After an iteration, I have a separate controller for each component, with these controllers all managed by a small InstrumentControllerBase (or its derivatives). The composite system will receive "input" either programmatically or via inter-hardware component triggering - in either case these interactions are routed to, and handled by, the appropriate controller. So, I have something that feels MVC-esque, but I don't know if that's because I'm forcing the point. With little direct MVC experience in application development, it's hard to know if I'm just trying to make my scenario fit MVC, where another pattern might be a good alternative or complimentary. My problem is, search results and wiki documentation of these family of patterns seems to immediately drop me into GUI-specific discussions. I understand "M means Model data and the V means View" - but do you call the superset pattern? Component-Commander-Controller? Whence can I exhume examples exemplary?

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• Asynchronous Controller is blocking requests in ASP.NET MVC through jQuery

  - by Jason

  I have just started using the AsyncController in my project to take care of some long-running reports. Seemed ideal at the time since I could kick off the report and then perform a few other actions while waiting for it to come back and populate elements on the screen. My controller looks a bit like this. I tried to use a thread to perform the long task which I'd hoped would free up the controller to take more requests: public class ReportsController : AsyncController { public void LongRunningActionAsync() { AsyncManager.OutstandingOperations.Increment(); var newThread = new Thread(LongTask); newThread.Start(); } private void LongTask() { // Do something that takes a really long time //....... AsyncManager.OutstandingOperations.Decrement(); } public ActionResult LongRunningActionCompleted(string message) { // Set some data up on the view or something... return View(); } public JsonResult AnotherControllerAction() { // Do a quick task... return Json("..."); } } But what I am finding is that when I call LongRunningAction using the jQuery ajax request, any further requests I make after that back up behind it and are not processed until LongRunningAction completes. For example, call LongRunningAction which takes 10 seconds and then call AnotherControllerAction which is less than a second. AnotherControllerAction simply waits until LongRunningAction completes before returning a result. I've also checked the jQuery code, but this still happens if I specifically set "async: true": $.ajax({ async: true, type: "POST", url: "/Reports.aspx/LongRunningAction", dataType: "html", success: function(data, textStatus, XMLHttpRequest) { // ... }, error: function(XMLHttpRequest, textStatus, errorThrown) { // ... } }); At the moment I just have to assume that I'm using it incorrectly, but I'm hoping one of you guys can clear my mental block!

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• Fatal error: Call to a member function escape() on a non-object in .....on line 10

  - by danyo

  i am making a simple javascript login form for wordpress. i have the form submitting to the following bit of php to handle the login: <?php get_header(); global $user_ID; if (!$user_ID) { if($_POST){ //We shall SQL escape all inputs $username = $wpdb->escape($_REQUEST['username']); $password = $wpdb->escape($_REQUEST['password']); $remember = $wpdb->escape($_REQUEST['rememberme']); if($remember) $remember = "true"; else $remember = "false"; $login_data = array(); $login_data['user_login'] = $username; $login_data['user_password'] = $password; $login_data['remember'] = $remember; $user_verify = wp_signon( $login_data, false ); //wp_signon is a wordpress function which authenticates a user. It accepts user info parameters as an array. if ( is_wp_error($user_verify) ) { echo "<span class='error'>Invalid username or password. Please try again!</span>"; exit(); } else { echo "<script type='text/javascript'>window.location='". get_bloginfo('url') ."'</script>"; exit(); } } else { //get_header(); ?> any ideas on why i am getting the error? Cheers, Dan

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