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  • How to detect changing directory size in Perl

    - by materiamage
    Hello, I am trying to find a way of monitoring directories in Perl, in particular the size of a directory, and upon detecting a change in directory size, perform a particular action. The issue I have is with large files that require a noticeable amount of time to copy into this directory, i.e. 100MB. What happens (in Windows, not Unix) is the system reserves enough disk space for the entire file, even though the file is still copying in progress. This causes problems for me, because my script will try to perform an action on this file that has not finished copying over. I can easily detect directory size changes in Unix via 'du', but 'du' in Windows does not behave the same way. Are there any accurate methods of detecting directory size changes in Perl? Edit: Some points to clarify: - My Perl script is only monitoring a particular directory, and upon detecting a new file or a new directory, perform an action on this new file or directory. It is not copying any files; users on the network will be copying files into the directory I am monitoring. - The problem occurs when a new file or directory appears (copied, not moved) that is significantly large ( 100MB, but usually a couple GB) and my program fires before this copy completes - In Unix I can easily 'du' to see that the file/directory in question is growing in size, and take the appropriate action - In Windows the size is static, so I cannot detect this change - opendir/readdir/closedir is not feasible, as some of the directories that appear may contain thousands of files, and I want to avoid the overhead of Ideally I would like my program to be triggered on change, but I am not sure how to do this. As of right now it busy waits until it detects a change. The change in file/directory size is not in my control.

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  • Scheduling Jobs On web server

    - by sirasad
    Hi Folks We Want to Create an online game like this.I think that ,this type of games have a scheduling software on web server. For Example : Player Click to create a resource And resource creation will be take a moment like 20 Minutes.(Every resource creation time will be different). This message will send to web server application but this message will not processed at same time for example must be processed after 20 Minutes. The web server application after getting the message must be put the order in the Queue. We have Some big problems : 1- The Jobs must be complete by the web server application Even the player Exit the Game. I think that we must create something like Windows service on Web Server. Can we do it? or Is there a better way? 2- The Second problem depended on problem 1 .Because we will have many Jobs (every player can create 20,30 Jobs in every Loggin and we will have thousands of users) , So Our Scheduling System Must be Work On time . it's possible that , there is 100 , 1000 jobs in a same second , if application Can't Done Jobs in him Second will be use the next second Time and the next second jobs will shift to next second and etc. How We can do for this problem ? Cheers Asad Safari Agile Coach , Scrum Master

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  • Attempting to Convert Byte[] into Image... but is there platform issues involved

    - by user305535
    Greetings, Current, I'm attempting to develop an application that takes a Byte Array that is streamed to us from a Linux C language program across a TCPClient (stream) and reassemble it back into an image/jpg. The "sending" application was developed by a off-site developer who claims that the image reassembles back into an image without any problems or errors in his test environment (all Linux)... However, we are not so fortunate. I (believe) we successfully get all of the data sent, storing it as a string (lets us append the stream until it is complete) and then we convert it back into a Byte[]. This appears to be working fine... But, when we take the byte[] we get from the streaming (and our string assembly) and try to convert it into an image using the System.Drawing.Image.FromStream() we get errors.... Anyone have any idea what we're doing wrong? Or, does anyone know if this is a cross-platform issue? We're developing our app for Windows XP and C# .net, but the off-site developer did his work in c and Linux... perhaps there's some difference as to how each Operating System Coverts Images into Byte Arrays? Anyway, here's the code for converting our received ByteArray (from the TCPClient Stream) into an image. This code works when we send an image from a test machine we built that RUNS on XP, but not from the Linux box... System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding(); byte[] imageBytes = encoding.GetBytes(data); MemoryStream ms = new MemoryStream(imageBytes, 0, imageBytes.Length); // Convert byte[] to Image ms.Write(imageBytes, 0, imageBytes.Length); System.Drawing.Image image = System.Drawing.Image.FromStream(ms, false); <-- DIES here, throws a {System.ArgumentException: Parameter is not valid.} error Any advice, suggestions, theories, or HELP would be GREATLY appreciated! Please let me know??? Best wishes all! Thanks in advance! Greg

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  • Help me with the simplest program for "Trusted" application

    - by idazuwaika
    Hi, I hope anyone from the large community here can help me write the simplest "Trusted" program that I can expand from. I'm using Ubuntu Linux 9.04, with TPM emulator 0.60 from Mario Strasser (http://tpm-emulator.berlios.de/). I have installed the emulator and Trousers, and can successfully run programs from tpm-tools after running tpmd and tcsd daemons. I hope to start developing my application, but I have problems compiling the code below. #include <trousers/tss.h> #include <trousers/trousers.h> #include <stdio.h> TSS_HCONTEXT hContext; int main() { Tspi_Context_Create(&hContext); Tspi_Context_Close(hContext); return 0; } After trying to compile with g++ tpm.cpp -o tpmexe I receive errors undefined reference to 'Tspi_Context_Create' undefined reference to 'Tspi_Context_Close' What do I have to #include to successfully compile this? Is there anything that I miss? I'm familiar with C, but not exactly so with Linux/Unix programming environment. ps: I am a part time student in Master in Information Security programme. My involvement with programming has been largely for academic purposes.

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  • Why is Delphi unable to infer the type for a parameter TEnumerable<T>?

    - by deepc
    Consider the following declaration of a generic utility class in Delphi 2010: TEnumerableUtils = class public class function InferenceTest<T>(Param: T): T; class function Count<T>(Enumerable: TEnumerable<T>): Integer; overload; class function Count<T>(Enumerable: TEnumerable<T>; Filter: TPredicate<T>): Integer; overload; end; Somehow the compiler type inference seems to have problems here: var I: Integer; L: TList<Integer>; begin TEnumerableUtils.InferenceTest(I); // no problem here TEnumerableUtils.Count(L); // does not compile: E2250 There is no overloaded version of 'Count' that can be called with these arguments TEnumerableUtils.Count<Integer>(L); // compiles fine end; The first call works as expected and T is correctly inferred as Integer. The second call does not work, unless I also add <Integer -- then it works, as can be seen in the third call. Am I doing something wrong or is the type inference in Delphi just not supporting this (I don't think it is a problem in Java which is why expected it to work in Delphi, too).

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  • Bookmarkable URLs after Ajax for Wicket

    - by Wolfgang
    There is this well-known problem that browsers don't put Ajax request in the request history and cause problems for bookmarkability, forward/back button, and refresh. Also, there is a common solution to that problem that appends the hash symbol # and some additional parameters to the URL by using Javascript window.location.hash = .... In this question a basic solution to this problem is proposed, for example. = My question is if such a solution has been integrated in Wicket, so that existing Wicket facilities are used and no custom Javascript had to be added. If not, I'd be interested in how this could be done. Such a solution had to answer the question what should be put after the hash. I like the idea that the bookmarkable URL that (in the non-Ajax case) were in front of the hash could be put behind it. For example, when you are on http://host/catalog and reach a page http://host/product/xyz the Ajax-triggered URL would be http://host/catalog#/product/xyz. Then it would be easy to write an onload handler that checks for the # and does a redirect to the URL after the hash.

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  • Moving UIScrollView in App

    - by jsetting32
    Currently, I am attempting to create the same effect as Yahoo! Weather's App where the vital day information is at the bottom of the page on the top of a UIScrollView, that's contained by a UIView. I am having a hard time thinking about how this is going to happen or how I should implement this. If the user taps on the top of the UIScrollView which is located near the bottom of the laoded UIView, and starts to scroll up (/), the UIScrollView's frame should be moved to the TOP of the current UIView's frame. So the UIScrollView's y-value should change to UIView's (self.view.frame.origin.y) if the user starts scrolling UP on the UIScrollView which is located on the UIView's y-pixel ~280. Here's what the UIViewController should look like in the beginning of loading the ViewController... Then once the user slides his finger from the bottom to the top of the screen... this should happen........ And when the user scrolls to the top of the UIScrollView with all the content within it... the view should go back to the start picture shown... How is this done? I was thinking several UIGestureRecognizer's and Instantiating the UIscrollview at the lower part of the UIView... _weatherView = [[UIScrollView alloc] initWithFrame:CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y + 250, self.view.bounds.size.width, self.view.bounds.size.height - 44)]; _weatherView.contentSize = CGSizeMake(self.view.bounds.size.width, self.view.bounds.size.height * 4); _weatherView.backgroundColor = [UIColor clearColor]; [self.view addSubview:_weatherView]; The adding some UIGestureRecognizer delegate method.... But anyone have any ideas on the UIGestureRecognizer delegate method? And how it should be implemented? I can write the psuedo-code but I am having problems finding the delegate methods :P Thank you!!! ---- Break Time.... :)

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  • Script to install and compile Python, Django, Virtualenv, Mercurial, Git, LessCSS, etc... on Dreamho

    - by tmslnz
    The Story After cleaning up my Dreamhost shared server's home folder from all the cruft accumulated over time, I decided to start afresh and compile/reinstall Python. All tutorials and snippets I found seemed overly simplistic, assuming (or ignoring) a bunch of dependencies needed by Python to compile all modules correctly. So, starting from http://andrew.io/weblog/2010/02/installing-python-2-6-virtualenv-and-virtualenvwrapper-on-dreamhost/ (so far the best guide I found), I decided to write a set-and-forget Bash script to automate this painful process, including along the way a bunch of other things I am planning to use. The Script I am hosting the script on http://bitbucket.org/tmslnz/python-dreamhost-batch/src/ The TODOs So far it runs fine, and does all it needs to do in about 900 seconds, giving me at the end of the process a fully functional Python / Mercurial / etc... setup without even needing to log out and back in. I though this might be of use for others too, but there are a few things that I think it's missing and I am not quite sure how to go for it, what's the best way to do it, or if this just doesn't make any sense at all. Check for errors and break Check for minor version bumps of the packages and give warnings Check for known dependencies Use arguments to install only some of the packages instead of commenting out lines Organise the code in a manner that's easy to update Optionally make the installers and compiling silent, with error logging to file failproof .bashrc modification to prevent breaking ssh logins and having to log back via FTP to fix it EDIT: The implied question is: can anyone, more bashful than me, offer general advice on the worthiness of the above points or highlight any problems they see with this approach? (see my answer to Ry4an's comment below) The Gist I am no UNIX or Bash or compiler expert, and this has been built iteratively, by trial and error. It is somehow going towards apt-get (well, 1% of it...), but since Dreamhost and others obviously cannot give root access on shared servers, this looks to me like a potentially very useful workaround; particularly so with some community work involved.

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  • IIS URL Rewriting: How can I reliably keep relative paths when serving multiple files?

    - by NVRAM
    My WebApp is part CMS, and when I serve up an HTML page to the user it typically contains relative paths in a.href and img.src attributes. I currently have them accessed by urls like: ~/get-data.aspx/instance/user/page.html -- where instance indicates the particular instance for the report and "user/page.html" is a path created by an external application that generates the content. This works pretty reliably with code in the application's BeginRequest method that translates the text after ".aspx" into a query string, then uses Context.RewritePath(). So far so good, but I've just tripped over something that took me by surprise: it appears that if any of the query string ("instance/user/page.html") happens to contain a plus sign ("+") the BeginRequest method is never called, and a 404 is immediately returned to the user. So my question is two-fold: Am I correct in my belief that a "+" would cause the 404, and if so are there other things that could cause similar problems? Is there a way around that problem (perhaps a different method than BeginRequest)? Is there a better way to preserve relative URL paths for generated content than what I'm using? I'd rather not require site admins to install a 3rd party rewrite tool if I can help it.

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  • VB6 Game Development

    - by CVS-2600Hertz-wordpress-com
    Hi All, I am developing a game in VB6 (plz don't ask me why :) ). The storyboard is ready and a rough implementation is underway. I am following a "pure-software-rendering" approach. (i.e. no DirectX, no openGL etc.) Amongst many others, the following "serious" problems exist: 2D alpha transparency reqd. to implement overlays. Parallax implementation to give depth-of-field illusion. Capturing mouse-scroll events globally (as in FPS-es; mapping them to changing weapon). Async sound play with absolute "near-zero-lag". Any ideas anyone. Please suggest any well documented library/ocx or sample-code. Plz do suggest solutions with good performance and as little overhead as possible. Also, anyone who has developed any games, and would be open to sharing her/his code would be highly appreciated. (any well-acknowledged VB games whose source-code i can study??) UPDATE: Here is a screen shot of GearHead Garage. This picture ought to describe what i was attempting in words above... :) Thank You

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  • Binding a Value from a View-Model to the View-Model of a child User Control in Silverlight?

    - by andrej351
    Hi there, So i have a UserControl for one of my Views and have another 'child' UserControl inside that. The outer 'parent' UserControl has a Collection on its View-Model and a Grid control on it to display a list of Items. I want to place another UserControl inside this UserControl to display a form representing the details of one Item. The outer / parent UserControl's View-Model already has a property on it to hold the currently selected Item and i would like to bind this to a DependancyProperty on the inner / child UserControl. I would then like to bind that DependancyProperty to a property on the child UserControl's View-Model. I can then set the DependancyProperty once in XAML with a binding expression and have the child UserControl do all its work in its View-Model like it should. The code i have looks like this.. Parent UserControl: <UserControl x:Class="ItemsListView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" DataContext="{Binding Source={StaticResource ServiceLocator}, Path=ItemsListViewModel}"> <!-- Grid Control here... --> <ItemDetailsView Item="{Binding Source={StaticResource ServiceLocator}, Path=ItemsListViewModel.SelectedItem}" /> </UserControl> Child UserControl: <UserControl x:Class="ItemDetailsView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" DataContext="{Binding Source={StaticResource ServiceLocator}, Path=ItemDetailsViewModel}" ItemDetailsView.Item="{Binding Source={StaticResource ServiceLocator}, Path=ItemDetailsViewModel.Item, Mode=TwoWay}"> <!-- Form controls here... --> </UserControl> The selected Item is bound to the DependancyProperty fine. However from the DependancyProperty to the child View-Model does not. I've used this sort of apporach in a WPF app without problems. It appears to be a situation where there are two concurrent bindings which need to work but with the same target for two sources. Why won't the second (in the child UserControl) binding work?? Is there a way to acheive the behaviour I'm after?? Cheers.

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  • little java help....

    - by jona
    Hi I am doing some practice problems and trying to print a diagonal line like the example below. I have writen the program you see below and I honestly dont understand what I am doing wrong. I m a java beginner and I cant see how to find the error. Example ( If you only see a straight line of stars...then imagine it diagonally....from top left to bottom right) * * * * * code: class Diagonal{ public static void main(String args[]) { int row, col; for(row = 1; row < 6; row++) { for(col = 1; col <= row; col++) { if(col==row){ System.out.print("*"); } else{ System.out.print(""); } System.out.println(); } } } } I am trying to learn for loops because they really confuse me. Another practice is to print a similar diagonal line but this time from right to left. I cant do that without getting this right however :( I believe they will be pretty similar? Above my reasining is this: As long as the column # is the same as the row number the print the line or otherwise leave a blank....what's wrong with how i did it? THANK YOU!

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  • Few Basic Questions in Overriding

    - by Dahlia
    I have few problems with my basic and would be thankful if someone can clear this. What does it mean when I say base *b = new derived; Why would one go for this? We very well separately can create objects for class base and class derived and then call the functions accordingly. I know that this base *b = new derived; is called as Object Slicing but why and when would one go for this? I know why it is not advisable to convert the base class object to derived class object (because base class is not aware of the derived class members and methods). I even read in other StackOverflow threads that if this is gonna be the case then we have to change/re-visit our design. I understand all that, however, I am just curious, Is there any way to do this? class base { public: void f(){cout << "In Base";} }; class derived:public base { public: void f(){cout << "In Derived";} }; int _tmain(int argc, _TCHAR* argv[]) { base b1, b2; derived d1, d2; b2 = d1; d2 = reinterpret_cast<derived*>(b1); //gives error C2440 b1.f(); // Prints In Base d1.f(); // Prints In Derived b2.f(); // Prints In Base d1.base::f(); //Prints In Base d2.f(); getch(); return 0; } In case of my above example, is there any way I could call the base class f() using derived class object? I used d1.base()::f() I just want to know if there any way without using scope resolution operator? Thanks a lot for your time in helping me out!

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  • Web development scheme for staging and production servers using Git Push

    - by ServAce85
    I am using git to manage a dynamic website (PHP + MySQL) and I want to send my files from my localhost to my staging and development servers in the most efficient and hassle-free way. I am currently convinced that the best way for me to approach this problem is to use this git branching model to organize my local git repo. From there, I will use the release branches to push to my staging server for testing. Once I am happy that the release code works on the staging server, I can then merge with my master branch and push that to my production server. Pushing to Staging Server: As noted in many introductory git posts, I could run into problems pushing into a non-bare repo, so, as suggested in this response, I plan to push the release branch to a bare repo on the server and have a post-receive hook that clones the bare repo to a non-bare repo that also acts as the web-hosted directory. Pushing to Production Server: Here's my newest source of confusion... In the response that I cited above, it made me curious as to why @Paul states that it's a completely different story when pushing to a live, development server. I guess I don't see the problem. Would it be safe and hassle-free to follow the same steps as above, but for the master branch? Where are the potential pit-falls? Config Files: With respect to configuration files that are unique to each environment (.htaccess, config.php, etc), it seems simplest to .gitignore each of those files in their respective repos on their respective servers. Can you see anything immediately wrong with this? Better solutions? Accessing Data: Finally, as I initially stated, the site uses MySQL databases to store data. How would you suggest I access that data (for testing purposes) from the staging server and localhost? I realize that I may have asked way too many questions for a single post, but since they're all related to the best way to set up this development scheme, I thought it was necessary.

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  • Add webservice reference, the classes in different file

    - by ArunDhaJ
    Hi, When I add webservice as service reference in my .Net project, it creates a service folder within "Service References". All the interfaces and classes are contained within that service folder. I wanted to know how to split the interface's method and classes. Actually I wanted the web service reference to import classes defined in different dll. I wanted to define this way because of my design constraints. I've 3 layered application. Of which third layer is communication layer which holds all web service references. second is business layer and first is presentation layer. If the class declarations are in layer-3 and I'm accessing those classes from presentation layer, it is logically a cross-layer-access-violation. Instead, I wanted a separate project which holds only the class declarations and this would be used in all 3 layers. I didn't faced any problems to achieve this with layer-1 and layer-2. But, I'm not sure how to make communication layer to use this common declaration dll. Your suggestion would help me to design my application better. Thanks in advance Regards ArunDhaJ

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  • .NET Regex - Replace multiple characters at once without overwriting?

    - by Everaldo Aguiar
    I'm implementing a c# program that should automatize a Mono-alphabetic substitution cipher. The functionality i'm working on at the moment is the simplest one: The user will provide a plain text and a cipher alphabet, for example: Plain text(input): THIS IS A TEST Cipher alphabet: A - Y, H - Z, I - K, S - L, E - J, T - Q Cipher Text(output): QZKL KL QJLQ I thought of using regular expressions since I've been programming in perl for a while, but I'm encountering some problems on c#. First I would like to know if someone would have a suggestion for a regular expression that would replace all occurrence of each letter by its corresponding cipher letter (provided by user) at once and without overwriting anything. Example: In this case, user provides plaintext "TEST", and on his cipher alphabet, he wishes to have all his T's replaced with E's, E's replaced with Y and S replaced with J. My first thought was to substitute each occurrence of a letter with an individual character and then replace that character by the cipherletter corresponding to the plaintext letter provided. Using the same example word "TEST", the steps taken by the program to provide an answer would be: 1 - replace T's with (lets say) @ 2 - replace E's with # 3 - replace S's with & 4 - Replace @ with E, # with Y, & with j 5 - Output = EYJE This solution doesn't seem to work for large texts. I would like to know if anyone can think of a single regular expression that would allow me to replace each letter in a given text by its corresponding letter in a 26-letter cipher alphabet without the need of splitting the task in an intermediate step as I mentioned. If it helps visualize the process, this is a print screen of my GUI for the program:

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  • Pecking order of pigeons?

    - by sc_ray
    I was going though problems on graph theory posted by Prof. Ericksson from my alma-mater and came across this rather unique question about pigeons and their innate tendency to form pecking orders. The question goes as follows: Whenever groups of pigeons gather, they instinctively establish a pecking order. For any pair of pigeons, one pigeon always pecks the other, driving it away from food or potential mates. The same pair of pigeons always chooses the same pecking order, even after years of separation, no matter what other pigeons are around. Surprisingly, the overall pecking order can contain cycles—for example, pigeon A pecks pigeon B, which pecks pigeon C, which pecks pigeon A. Prove that any finite set of pigeons can be arranged in a row from left to right so that every pigeon pecks the pigeon immediately to its left. Since this is a question on Graph theory, the first things that crossed my mind that is this just asking for a topological sort of a graphs of relationships(relationships being the pecking order). What made this a little more complex was the fact that there can be cyclic relationships between the pigeons. If we have a cyclic dependency as follows: A-B-C-A where A pecks on B,B pecks on C and C goes back and pecks on A If we represent it in the way suggested by the problem, we have something as follows: C B A But the above given row ordering does not factor in the pecking order between C and A. I had another idea of solving it by mathematical induction where the base case is for two pigeons arranged according to their pecking order, assuming the pecking order arrangement is valid for n pigeons and then proving it to be true for n+1 pigeons. I am not sure if I am going down the wrong track here. Some insights into how I should be analyzing this problem will be helpful. Thanks

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  • Linux C debugging library to detect memory corruptions

    - by calandoa
    When working sometimes ago on an embedded system with a simple MMU, I used to program dynamically this MMU to detect memory corruptions. For instance, at some moment at runtime, the foo variable was overwritten with some unexpected data (probably by a dangling pointer or whatever). So I added the additional debugging code : at init, the memory used by foo was indicated as a forbidden region to the MMU; each time foo was accessed on purpose, access to the region was allowed just before then forbidden just after; a MMU irq handler was added to dump the master and the address responsible of the violation. This was actually some kind of watchpoint, but directly self-handled by the code itself. Now, I would like to reuse the same trick, but on a x86 platform. The problem is that I am very far from understanding how is working the MMU on this platform, and how it is used by Linux, but I wonder if any library/tool/system call already exist to deal with this problem. Note that I am aware that various tools exist like Valgrind or GDB to manage memory problems, but as far as I know, none of these tools car be dynamically reconfigured by the debugged code. I am mainly interested for user space under Linux, but any info on kernel mode or under Windows is also welcome!

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  • Best practice to structure large html-based project

    - by AntonAL
    I develop Rails based website, enjoying using partials for some common "components" Recently, i faced a problem, that states with CSS interference. Styles for one component (described in css) override styles for another components. For example, one component has ... <ul class="items"> ... and another component has it too. But that ul's has different meaning in these two components. On the other hand, i want to "inherit" some styles for one component from another. For example: Let, we have one component, called "post" <div class="post"> <!-- post's stuff --> <ul class="items"> ... </ul> </div And another component, called "new-post": <div class="new-post"> <!-- post's stuff --> <ul class="items"> ... </ul> <!-- new-post's stuff --> <div class="tools">...</div> </div Post and new-post have something similar ("post's stuff") and i want to make CSS rules to handle both "post" and "new-post" New post has "subcomponents", for example - editing tools, that has also: <ul class="items"> This is where CSS rules starting to interfer - some rules, targeted for ul.items (in post and new-post) applies subcomponent of new-post, called "tools" On the one hand - i want to inherit some styles On the other hand, i want to get better incapsulation What are the best practices, to avoid such kind of problems ?

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  • MySQL Ratings From Two Tables

    - by DirtyBirdNJ
    I am using MySQL and PHP to build a data layer for a flash game. Retrieving lists of levels is pretty easy, but I've hit a roadblock in trying to fetch the level's average rating along with it's pointer information. Here is an example data set: levels Table: level_id | level_name 1 | Some Level 2 | Second Level 3 | Third Level ratings Table: rating_id | level_id | rating_value 1 | 1 | 3 2 | 1 | 4 3 | 1 | 1 4 | 2 | 3 5 | 2 | 4 6 | 2 | 1 7 | 3 | 3 8 | 3 | 4 9 | 3 | 1 I know this requires a join, but I cannot figure out how to get the average rating value based on the level_id when I request a list of levels. This is what I'm trying to do: SELECT levels.level_id, AVG(ratings.level_rating WHERE levels.level_id = ratings.level_id) FROM levels I know my SQL is flawed there, but I can't figure out how to get this concept across. The only thing I can get to work is returning a single average from the entire ratings table, which is not very useful. Ideal Output from the above conceptually valid but syntactically awry query would be: level_id | level_rating 1| 3.34 2| 1.00 3| 4.54 My main issue is I can't figure out how to use the level_id of each response row before the query has been returned. It's like I want to use a placeholder... or an alias... I really don't know and it's very frustrating. The solution I have in place now is an EPIC band-aid and will only cause me problems long term... please help!

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  • Introduction to vectorizing in MATLAB - any good tutorials?

    - by Gacek
    I'm looking for any good tutorials on vectorizing (loops) in MATLAB. I have quite simple algorithm, but it uses two for loops. I know that it should be simple to vectorize it and I would like to learn how to do it instead of asking you for the solution. But to let you know what problem I have, so you would be able to suggest best tutorials that are showing how to solve similar problems, here's the outline of my problem: B = zeros(size(A)); % //A is a given matrix. for i=1:size(A,1) for j=1:size(A,2) H = ... %// take some surrounding elements of the element at position (i,j) (i.e. using mask 3x3 elements) B(i,j) = computeSth(H); %// compute something on selected elements and place it in B end end So, I'm NOT asking for the solution. I'm asking for a good tutorials, examples of vectorizing loops in MATLAB. I would like to learn how to do it and do it on my own.

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  • Opa app does not load in Internet Explorer when compiled with Opa 1.1.1

    - by Marcin Skórzewski
    I did a minor update to the already working application and then had problems using new version of Opa compiler. First problem - runtime exception Since the original deployment Opa 1.1.1 has been released and it resulted in error: events.js:72 throw er; // Unhandled 'error' event ^ Error: listen EADDRINUSE at errnoException (net.js:901:11) at Server._listen2 (net.js:1039:14) at listen (net.js:1061:10) at Server.listen (net.js:1127:5) at global.BslNet_Http_server_init_server (/opt/mlstate/lib/opa/stdlib/server.opp/serverNodeJsPackage.js:223:1405) at global.BslNet_Http_server_init_server_cps (/opt/mlstate/lib/opa/stdlib/server.opp/serverNodeJsPackage.js:226:15) at __v1_bslnet_http_server_init_server_cps_b970f080 (/opt/mlstate/lib/opa/stdlib/stdlib.qmljs/stdlib.core.web.server.opx/main.js:1:175) at /opt/mlstate/lib/opa/stdlib/stdlib.qmljs/stdlib.core.web.server.opx/main.js:440:106 at global.execute_ (/opt/mlstate/lib/opa/static/opa-js-runtime-cps/main.js:19:49) at /opt/mlstate/lib/opa/static/opa-js-runtime-cps/main.js:17:78 I decided to build Opa from sources and it helped, but another problem occurred :( Second problem - stops to support the IE Application stopped to work in Internet Explorer. I tried two different machines (Windows XP and 7) with IE 8 and 10. Web page does not load at all (looks like the network problem, but the same URL works fine in Firefox). I confirmed the same problem with "Hello world" from the Opa tutorial compiled with both Opa stable 1.1.1 and build from sources. I suspected that the problem is due to Node.js update (Opa = 1.1.1 requires Node 0.10.* - now I am using 0.10.12, but I also tried other 0.10-s), but "Hello world" from the Node's from page works fine. I am running the app on OSX developer box and Linux Debian 7.0 server. Any suggestions what am I doing wrong? PS. I was off the business for a while. Anyone knows what happened to the Opa forum? Signing is seams not to work.

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  • Where should I store shared resources between LocalSystem and regular user with UAC?

    - by rwired
    My application consists of two parts: A Windows Service running under the LocalSystem account and a client process running under the currently logged in regular user. I need to deploy the application across Windows versions from XP up to Win7. The client will retrieve files from the web and collect user data from the user. The service will construct files and data of it's own which the client needs to read. I'm trying to figure out the best place (registry or filesystem, or mix) to store all this. One file the client or service needs to be able to retrieve from the net is an update_patch executable which needs to run whenever an upgrade is available. I need to be sure the initial installer SETUP.EXE, and also the update_patch can figure out this ideal location and set a RegKey to be read later by both client and server telling them the magic location (The SETUP.EXE will run with elevated privileges since it needs to install the service) On my Win7 test system the service %APPDATA% points to: C:\Windows\system32\config\systemprofile\AppData\Roaming and the %APPDATA% of the client points to: C:\Users\(username)\AppData\Roaming Interestingly Google Chrome stores everything (App and Data) in C:\Users\(username)\AppData\Local\Google\Chrome Chrome runs pretty much in exactly the way I want my suite to run (able to silently update itself in the background) What I'm trying to avoid is nasty popups warning the user that the app wants to modify the system, and I want to avoid problems when VirtualStore doesn't exist because the user is running XP/2000/2003 or has UAC turned off. My target audience are non-tech-savvy general Windows users.

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  • SQLAlchemy: who is in charge of the "session"? ( and how to unit-test with sessions )

    - by Nick Perkins
    I need some guidance on how to use session objects with SQLAlchemy, and how to organize Unit Tests of my mapped objects. What I would like to able to do is something like this: thing = BigThing() # mapped object child = thing.new_child() # create and return a related object thing.save() # will also save the child object In order to achieve this, I was thinking of having the BigThing actually add itself ( and it's children ) to the database -- but maybe this not a good idea? One reason to add objects as soon as possible is Automatic id values that are assigned by the database -- the sooner they are available, the fewer problems there are ( right? ) What is the best way to manage session objects? Who is in charge of the session? Should it be created only when required? or saved for a long time? What about Unit Tests for my mapped objects?...how should the session be handled? Is it ever OK to have mapped objects just automatically add themselves to a database? or is that going to lead to trouble?

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  • problem creating jpg thumb with php

    - by Ross
    Hi, I am having problems creating a thumbnail from an uploaded image, my problem is (i) the quality (ii) the crop http://welovethedesign.com.cluster.cwcs.co.uk/phpimages/large.jpg http://welovethedesign.com.cluster.cwcs.co.uk/phpimages/thumb.jpg If you look the quality is very poor and the crop is taken from the top and is not a resize of the original image although the dimesions mean it is in proportion. The original is 1600px wide by 1100px high. Any help would be appreciated. $thumb = $targetPath."Thumbs/".$fileName; $imgsize = getimagesize($targetFile); $image = imagecreatefromjpeg($targetFile); $width = 200; //New width of image $height = 138; //This maintains proportions $src_w = $imgsize[0]; $src_h = $imgsize[1]; $thumbWidth = 200; $thumbHeight = 138; // Intended dimension of thumb // Beyond this point is simply code. $sourceImage = imagecreatefromjpeg($targetFile); $sourceWidth = imagesx($sourceImage); $sourceHeight = imagesy($sourceImage); $targetImage = imagecreate($thumbWidth,$thumbHeight); imagecopyresized($targetImage,$sourceImage,0,0,0,0,$thumbWidth,$thumbWidth,imagesx($sourceImage),imagesy($sourceImage)); //imagejpeg($targetImage, "$thumbPath/$thumbName"); imagejpeg($targetImage, $thumb); chmod($thumb, 0755);

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