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  • Object-oriented GUI development in python

    - by ptabatt
    Hey guys, new programmer here. I have an assignment for class and I'm stuck... What I need to do is a create a GUI that gives someone a basic arithmetic problem in one box, asks the person to answer it, evaluates it, and tells you if you're right or wrong... Basically, what I have is this: [code] class Lesson(Frame): def init (self, parent=None): Frame.init(self, parent) self.pack() Lesson.make_widgets(self) def make_widgets(self): Label(self, text="").pack(side=TOP) ent = Entry(self) self.a = randrange(1,10) self.b = randrange(1,10) self.expr = choice(["+","-"]) ent.insert(END, str(self.a) + str(self.expr) + str(self.a)) [/code] I've broken this down into many little steps and basically, what I'm trying to do right now is insert a default random expression into the first entry widget. When I run this code, I just get a blank Label. Why is that? How can I put a something like "7+7" into the box? If you absolutely need background to the problem, it's question #3 on this link. http://reed.cs.depaul.edu/lperkovic/csc242/homeworks/Homework8.html -Thanks for all help in advance.

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  • C# : Forcing a clean run in a long running SQL reader loop?

    - by Wardy
    I have a SQL data reader that reads 2 columns from a sql db table. once it has done its bit it then starts again selecting another 2 columns. I would pull the whole lot in one go but that presents a whole other set of challenges. My problem is that the table contains a large amount of data (some 3 million rows or so) which makes working with the entire set a bit of a problem. I'm trying to validate the field values so i'm pulling the ID column then one of the other cols and running each value in the column through a validation pipeline where the results are stored in another database. My problem is that when the reader hits the end of handlin one column I need to force it to immediately clean up every little block of ram used as this process uses about 700MB and it has about 200 columns to go through. Without a full Garbage Collect I will definately run out of ram. Anyone got any ideas how I can do this? I'm using lots of small reusable objects, my thought was that I could just call GC.Collect() on the end of each read cycle and that would flush everything out, unfortunately that isn't happening for some reason.

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  • iPhone: detect "touch-and-drag" gesture from UIBarButtonItem?

    - by Greg Maletic
    I have an "add" button that's represented by a UIBarButtonItem. Hitting the "add" button adds an object into a list that represents a moment in time. By default, that time is "now"...but I'd like to be able to use dragging behavior to let the user specify earlier times for the object. Here's the behavior I want to implement: If the user touches on the UIBarButtonItem and lets go quickly, an object is added to the list that represents "now." If the user touches on the UIBarButtonItem and drags, a little UI pops up that shows the time that the distance of their drag represents. The further they drag, the further back in time their touch will represent. When they let go, the object representing an earlier time will get added to the list. (Though the description of the behavior is complicated, I'm convinced this will be pretty intuitive for users of the app.) I haven't implemented code for anything but the most simple touches in the past, and I'm at a loss as to the best way to try this. Does anyone have any suggestions, or could point me towards some sample code that implements something like this? Thanks very much.

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  • How many custom tabs can I add to a Facebook page?

    - by Maxi Ferreira
    I'm building a web application to create custom tabs and add them to the user's Facebook fanpages. I know how the process of "installing" FB apps into FB pages so they show up as Page Tabs works, but the problem is the client wants to allow the user to create unlimited Page Tabs for a single FB Page. So I have basically two questions. 1 - Can I resue a single FB App to be included into the same page several times? If so, is there a way to know what is the "id" of that Page Tab? So, if I have my FB App to look for the Tab content in http://www.mywebapp.com/tab/, I know I get a signed_request with the App ID and the Page ID, but if that same App is installed several times into the same Page, I don't know what's the Tab the user have cliked on. I know it's a little big messy, and I don't think there's a way to do this. So my next question is probably more accurate. 2 - Is there a limit on how many Tabs can I add to a single Facebook page? This way, if there's a limit of, say, 12 Tabs, I can create 12 FB Tab Apps, store the ID's and then I know which Tab of which Page the user is currently viewing. Thanks in advice! Maxi

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  • JDBC transaction dead-lock solution required?

    - by user49767
    It's a scenario described my friend and challenged to find solution. He is using Oracle database and JDBC connection with read committed as transaction isolation level. In one of the transaction, he updates a record and executes selects statement and commits the transaction. when everything happening within single thread, things are fine. But when multiple requests are handled, dead-lock happens. Thread-A updates a record. Thread B updates another record. Thread-A issues select statement and waits for Thread-B's transaction to complete the commit operation. Thread-B issues select statement and waits for Thread-A's transaction to complete the commit operation. Now above causes dead-lock. Since they use command pattern, the base framework allows to issue commit only once (at the end of all the db operation), so they are unable to issue commit immediately after select statement. My argument was Thread-A supposed to select all the records which are committed and hence should not be issue. But he said that Thread-A will surely wait till Thread-B commits the record. is that true? What are all the ways, to avoid the above issue? is it possible to change isolation-level? (without changing underlying java framework) Little information about base framework, it is something similar to Struts action, their each and every request handled by one action, transaction begins before execution and commits after execution.

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  • How to not use JavaScript with in the elements events attributes but still load via AJAX

    - by thecoshman
    I am currently loading HTMl content via AJAX. I have code for things on different elements onclick attributes (and other event attributes). It does work, but I am starting to find that the code is getting rather large, and hard to read. I have also read that it is considered bad practice to have the event code 'inline' like this and that I should really do by element.onclick = foobar and have foobar defined somewhere else. I understand how with a static page it is fairly easy to do this, just have a script tag at the bottom of the page and once the page is loaded have it executed. This can then attach any and all events as you need them. But how can I get this sort of affect when loading content via AJAX. There is also the slight case that the content loaded can very depending on what is in the database, some times certain sections of HTML, such as tables of results, will not even be displayed there will be something else entirely. I can post some samples of code if any body needs them, but I have no idea what sort of things would help people with this one. I will point out, that I am using Jquery already so if it has some helpful little functions that would be rather sweet¬

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  • KaZip for C++Builder2009/Delphi

    - by Katsumi
    Hi. I have download and install KaZip2.0 on C++Builder2009 (with little minor changes = only set type String to AnsiString). I have write: KAZip1->FileName = "test.zip"; KAZip1->CreateZip("test.zip"); KAZip1->Active = true; KAZip1->Entries->AddFile("pack\\text.txt","xxx.txt"); KAZip1->Active = false; KAZip1->Close(); now he create a test.zip with included xxx.txt (59byte original, 21byte packed). I open the archiv in WinRAR successful and want open the xxx.txt, but WinRAR says file is corrupt. :( What is wrong? Can somebody help me? Extract not working, because file is corrupt? KAZip1->FileName = "test.zip"; KAZip1->Active = true; KAZip1->Entries->ExtractToFile("xxx.txt","zzz.txt"); KAZip1->Active = false; KAZip1->Close();

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  • Advice on using .Net WorkFlow State Machine. What would you do?

    - by jlafay
    So I've been tasked at work to write windows services to replace some old legacy VB6 WinForms apps currently running as services, consistently repeating tasks day-to-day. To give some general background, they have there own state machines built in to handle decision basing and not utilizing threading. A lot of the senior developers here thought it would be worth a try to look into WorkFlow to replace the state machines rather than write my own business logic and try threading it programmaticly. So it's WF vs. the "Old College Try" I suppose. My concern is that there aren't many books on the topic, and since it was implemented in .Net I've heard very little about it being used. I brought this up at work and another developer mentioned that it's because Biz Talk never really caught on and it was designed for that. So is it broken? Do you think it will be supported long enough to not worry so much? I don't want an ill-functioning process injected into my services, my new babies at work, and then have WF's keel over. Leaving me with having to replace them with my own code in the event of an emergency; which does not seem like much of a grand scenario to me. Any suggestions, recommendations would be super.

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  • Question about memory allocation when initializing char arrays in C/C++.

    - by Carlos Nunez
    Before anything, I apologize if this question has been asked before. I am programming a simple packet sniffer for a class project. For a little while, I ran into the issue where the source and destination of a packet appeared to be the same. For example, the source and destination of an Ethernet frame would be the same MAC address all of the time. I custom-made ether_ntoa(char *) because Windows does not seem to have ethernet.h like Linux does. Code snippet is below: char *ether_ntoa(u_char etheraddr[ETHER_ADDR_LEN]) { int i, j; char eout[32]; for(i = 0, j = 0; i < 5; i++) { eout[j++] = etheraddr[i] >> 4; eout[j++] = etheraddr[i] & 0xF; eout[j++] = ':'; } eout[j++] = etheraddr[i] >> 4; eout[j++] = etheraddr[i] & 0xF; eout[j++] = '\0'; for(i = 0; i < 17; i++) { if(eout[i] < 10) eout[i] += 0x30; else if(eout[i] < 16) eout[i] += 0x57; } return(eout); } I solved the problem by using malloc() to have the compiler assign memory (i.e. instead of char eout[32], I used char * eout; eout = (char *) malloc (32);). However, I thought that the compiler assigned different memory locations when one sized a char-array at compile time. Is this incorrect? Thanks! Carlos Nunez

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  • How to convert many thousands of lines of VBScript to C#?

    - by Ross Patterson
    I have a collection of about 10,000 small VBScript programs (50-100 lines each) and a small collection of larger ones, and I'm looking for a way to convert them to C# without resorting to by-hand transliteration. The programs are automated test cases for a web application, written for HP/Mercury's QuickTest Pro, and I'm trying to turn them into test cases for Selenium. Luckily, the tests appear to be well-written, using a library of building blocks and idioms (the larger programs), so the test cases actually resemble a domain-specific language more than they do VBScript, and the QTP-ness is well-buried inside the libraries. Ideally, what I'm searching for is a tool that can do the syntactic transformation from VBScript to C# for both the dsl-ish test cases and also the more complicated building-block libraries. That would leave me with a manual cleanup of the libraries, and probably very little work on the test cases. If I could find a VBScript-to-VB.NET translator, I'd take that also, as I suspect I could compile the VB.NET and then de-compile to C# using .NET Relector or something similar. Plan B is to write a translator of my own for the test cases, since they're in a very straight-line style, but it wouldn't help with the libraries. Any suyggestions? I haven't written a compiler in at least 15 years, and while I haven't forgotten how, I'm not looking forward to it - least of all for VBScript!

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  • How can I get all content within <table></table> tags using a regex?

    - by Bob Dylan
    So I'm writing an application that will do a little screen scrapping. All the pages (about 1000 or so) contain this line: <table border="0" cellspacing="3"> <tr><td>First rows stuff</td></tr> <tr> <td> The data I want is in here <br /> and it's seperated by these annoying <br /> 's. No id's, classes, or even a single <p> tag. Just a bunch of <br /> tags. </td> </tr> </table> So I just need to get the data within the 2nd row out. How can I do this? Should I use a regex or something else?

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  • What can I read from the iPad Camera Connection Kit?

    - by HELVETICADE
    I'm building a small controller device that I'd like to partner with a computer. I've settled on using OSC out from my custom built hardware and am pretty satisfied with what I can get from WOscLib. Two goals I'd like to achieve are portability and a very ratio between battery:computing power, and this has lured me towards using iPhoneOS to accomplish my goals. I think the iPad would suit my needs perfectly, except that using wifi to broadcast OSC out from my device requires a third device and would destroy the goal of portability, whilst also introducing potential latency and stability headaches. My question is pretty simple: Can I push my OSC-out FROM my controller TO an iPad via USB and the Camera Connection Kit? If I could accomplish this, the two major goals of my project would be fulfilled very nicely. This seems like it should be a simple little question, but researching this obsessively over the past few weeks has left me more almost more uncertain than if I had done no research at all. I'd really like some more confidence before I go down this route, and it seems like it should be possible. Any insight would be very, very appreciated.

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  • How to (unit-)test data intensive PL/SQL application

    - by doom2.wad
    Our team is willing to unit-test a new code written under a running project extending an existing huge Oracle system. The system is written solely in PL/SQL, consists of thousands of tables, hundreds of stored procedures packages, mostly getting data from tables and/or inserting/updating other data. Our extension is not an exception. Most functions return data from a quite complex SELECT statementa over many mutually bound tables (with a little added logic before returning them) or make transformation from one complicated data structure to another (complicated in another way). What is the best approach to unit-test such code? There are no unit tests for existing code base. To make things worse, only packages, triggers and views are source-controlled, table structures (including "alter table" stuff and necessary data transformations are deployed via channel other than version control). There is no way to change this within our project's scope. Maintaining testing data set seems to be impossible since there is new code deployed to the production environment on weekly basis, usually without prior notice, often changing data structure (add a column here, remove one there). I'd be glad for any suggestion or reference to help us. Some team members tend to be tired by figuring out how to even start for our experience with unit-testing does not cover PL/SQL data intensive legacy systems (only those "from-the-book" greenfield Java projects).

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  • Why does Jcreator show iIlegal start of expression?

    - by Inusual Whisper Sinclair
    I am new at programming and currently in our classes we are learning java. I am trying to create a routine in which I need to use String variables only. Below it is the code in which I am working with: public static void main(String[] args) throws java.io.IOException { BufferedReader in = new BufferedReader(new InputStreamReader(System. in )); PrintStream out = System.out; String hair.equals("damagedHair"); cutHair(marvin); cleanHair(michelle); for (int i = 0; i < 2; i++) { static void cutHair(String marvin) { String cabello; marvin.equals(hair); if (marvin.equals("damagedHair")) { cabello.equals("newHaircut"); result(hair); } static void cleanHair(String michelle) { String hair; michelle.equals(hair); if (michelle.equals(newHaircut)) { hair.equals("putShampooAndConditioner"); result(hair); } static void result(String pHair) {; PrintStream out = System.out; out.println("============="); out.println(pHair); out.println("============="); } } Jcreator is giving me an error that says Illegal start of expression and also java 50 error ';' expected. I am not sure why is this coming up and I am a little confused as to whether I am doing something I am not supposed to and how to correct it. Sorry about the double posting, this is the right message. Need some help from you guys to figure this out. Thanks in advanced!

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  • Read Java in as Hex

    - by James
    Hi, I have tried to solve this but I keep coming up with stuff that is no help I'm sure this is easy (when you know how of course ;) ) What I would like to do is read in a file using a byte stream like below: while((read = in.read()) != -1){ //code removed to save space Integer.toHexString(read); System.out.println(read); } When it prints out the Hex to the screen it will print out numbers fine e.g 31 13 12 0 but when it comes to a hex code that should be 01 31 it will print 0 131. I want to read it in to a variable like you would see in a hex editor i.e 00 11 21 31 no single numbers as i need to scan the whole file and look for patterns which I know how to do I'm just stuck on this :/ so in short i need a variabe to contain the two hex characters i.e int temp = 01 not int temp = 0 , I hope this all makes sense, I'm a little confused as it's 3am! If anyone knows how to do this I would be most greatful, p.s thanks for the help in advance this site has saved me loads of research and have learnt a lot! Many thanks.

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  • How should developers cope with so many GUI configuration combinations?

    - by shawn-harrison
    These days, any decent Windows desktop application must perform well and look good under the following conditions: XP and Vista and Windows 7. 32 bit and 64 bit. With and without Themes. With and without Aero. At 96 and 120 and perhaps custom DPIs. One or more monitors (screens). Each OS has its own preferred font. Oh my! What is a lowly little Windows desktop application developer to do? :( I'm hoping to get a thread started with suggestions on how to deal with this GUI dilemma. First off, I'm on Delphi 7. a) Does Delphi 2010 bring anything new to the table to help with this situation? b) Should we pick an aftermarket component suite and rely on them to solve all these problems? c) Should we go with an aftermarket skinning engine? d) Perhaps a more HTML-type GUI is the way to go. Can we make a relatively complex GUI app with HTML that doesn't require using a browser? (prefer to keep it form based) e) Should we just knuckle down and code through each one of these scenarios and quit bitching about it? f) And finally, how in the world are we supposed to test all these conditions?

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  • GitHub solution for personal repo

    - by Luke Maurer
    So I've got my private SVN repo on my home server, and it has maybe 30 different modules thrown together in it, ranging from abortive throw-away larks to a few endeavors that might actually go somewhere someday. But a recent filesystem failure (BTW, never ever EVER use XFS without a battery-backed hardware RAID) has me spooked and thinking of using a DVCS for all that. I've also just had quite the swig of the Git koolaid, and I've been working with GitHub of late, so that's where I'm looking right now. Of course, it would be silly to shell out major cash for a separate private Git repo for every little project, and I don't want to have to be selective about what I throw up there (I love all my children :-D ), so I'll have to be somewhat creative about this. I can happily use SSH to my home box to use Git the way I've been using SVN, and I'm thinking from there I could amalgamate everything into, say, a big project with 30 submodules, which I then push to GitHub. What'd be a sane way to set this up? Does using submodules sound feasible? How do I sync it all to my private GitHub repo? Cron job? Git hook? I'd love to hear it if anyone's done something similar. I'm not really married to Git or GitHub, so a sufficiently compelling feature of another solution might sway me. But if your answer does involve a different system (especially a different VCS), be advised it'll be a tougher sell :-)

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  • Machine leaning algorithm for data classification.

    - by twk
    Hi all, I'm looking for some guidance about which techniques/algorithms I should research to solve the following problem. I've currently got an algorithm that clusters similar-sounding mp3s using acoustic fingerprinting. In each cluster, I have all the different metadata (song/artist/album) for each file. For that cluster, I'd like to pick the "best" song/artist/album metadata that matches an existing row in my database, or if there is no best match, decide to insert a new row. For a cluster, there is generally some correct metadata, but individual files have many types of problems: Artist/songs are completely misnamed, or just slightly mispelled the artist/song/album is missing, but the rest of the information is there the song is actually a live recording, but only some of the files in the cluster are labeled as such. there may be very little metadata, in some cases just the file name, which might be artist - song.mp3, or artist - album - song.mp3, or another variation A simple voting algorithm works fairly well, but I'd like to have something I can train on a large set of data that might pick up more nuances than what I've got right now. Any links to papers or similar projects would be greatly appreciated. Thanks!

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  • wpf: capturing mouse does not work

    - by amethyste
    hello I am developing an kind of outlook calendar application where I need to make the appointment resizable from mouse. My first try with a thumb did not work properly so I tried another way. What I did is that: 1) on the botton of the appointmennt panel I added a rectangle to figure out the resize zone (the thumb). The appointment panel is put on a grid panel. 2) I intercept down event on the rectangle and send event to this code: private Point startPoint; private void OnResizeElementMouseDown(object sender, MouseButtonEventArgs e) { e.Handled = true; this.MouseMove += new MouseEventHandler(ResizeEndElement_MouseMove); this.MouseLeftButtonUp += new MouseButtonEventHandler(OnResizeElementMouseUp); // some code to perform new height computation Mouse.Capture(this); } where this is the appointment panel that own the thumb. Decreasing height works well. But increasing is more difficult. If I move the mouse very very slowly it's OK, if I speed it up a little bit it tends to leave out the appointment panel and then all MouseMove event are lost. I thought Mouse.Capture() was propose to solve this kind of problem, but in fact not. Does anybody know what is wrong in my code?

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  • When memory is actually freeded?

    - by zhyk
    Hello all. I'm trying to understand memory management stuff in Objective-C. If I see the memory usage listed by Activity Monitor, it looks like memory is not being freed (I mean column rsize). But in "Object Allocations" everything looks fine. Here is my simple code: #import <Foundation/Foundation.h> int main (int argc, const char * argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; NSInteger i, k=10000; while (k>0) { NSMutableArray *array = [[NSMutableArray alloc]init]; for (i=0;i<1000*k; i++) { NSString *srtring = [[NSString alloc] initWithString:@"string...."]; [array addObject:srtring]; [srtring release]; srtring = nil; } [array release]; array = nil; k-=500; } [NSThread sleepForTimeInterval:5]; [pool release]; return 0; } As for retain and release it's cool, everything is balanced. But rsize decreases only after quitting from this little program. Is it possible to "clean" memory somehow before quitting?

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  • Does fast typing influence fast programming? [closed]

    - by Lukasz Lew
    Many young programmers think that their bottleneck is typing speed. After some experience one realizes that it is not the case, you have to think much more than type. At some point my room-mate forced me to turn of the light (he sleeps during the night). I had to learn to touch type and I experienced an actual improvement in programming skill. The most surprising was that the improvement not due to sheer typing speed, but to a change in mindset. I'm less afraid now to try new things and refactor them later if they work well. It's like having a new tool in the bag. Have anyone of you had similar experience? Now I trained a touch typing a little with KTouch. I find auto-generate lessons the best. I can use this program to create new lessons out of text files but it's only verbatim training, not auto-generated based on a language model. Do you know any touch typing program that allows creation of custom, but randomized lessons?

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  • Static files in (Java) App Engine not accessible.

    - by fiXedd
    The example documentation says that you simply need to place your files in war/ (or a subdirectory) and they should be accessible from the host (as long as they aren't JSPs or in WEB-INF). For example, if you place foo.css in war/ then you should be able to access it at http://localhost:8080/foo.css. However, this isn't working for me at all. NONE of my static files are accessible. The docs on appengine-web.xml say that you can also specifically denote certain types as static. I've tried this as well and it makes no difference. Am I missing something obvious? UPDATE: Turns out one of the mappings in my web.xml was a little too aggressive. The following was the culprit: <servlet> <servlet-name>Main</servlet-name> <servlet-class>MainServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>Main</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> It seems that it was grabbing everything that wasn't grabbed be one of the other rules, which I don't understand because there was no * on the end of the url-pattern. It also seems to be directly contradictory to the documentation that says: Note: Static files, files that are served verbatim to users such as images, CSS or JavaScript, are handled separately from paths mentioned in the deployment descriptor. A request for a URL path that matches a path to a file in the WAR that's considered a static file will serve the file, regardless of servlet and filter mappings in the deployment descriptor. You can exclude files from those treated as static files using the appengine-web.xml file. So, how can I have a rule that matches the base of my domain (eg. http://www.example.com/) and still allows the static files to filter through?

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  • VSTO - Outlook 2007 How do I show a user property even when it's not present?

    - by Yandros
    I have added user property in a mail folder, let's call it UserProperty01. Some of the folder items have this property, some don't. I need to show in the folder's view if that property is set or not, so I added another property called UserProperty01Present, and I set it to true when I set the original property and false when I deleted it; then I added it to the folder's view. The problem is that the little checkbox appears checked in those mails where the property is set, blank in those where the property was deleted... and nowhere at all in those where the property was never set in the first place. My question is, is there any way to show the blank checkbox when the property is not set? The only alternative I found so far is looking in every mail item and setting it to false when it's not set every time the folder is opened; needless to say, I'm not very happy with this solution. Is there any other way? Thank you for your time.

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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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  • [Ruby] Object assignment and pointers

    - by Jergason
    I am a little confused about object assignment and pointers in Ruby, and coded up this snippet to test my assumptions. class Foo attr_accessor :one, :two def initialize(one, two) @one = one @two = two end end bar = Foo.new(1, 2) beans = bar puts bar puts beans beans.one = 2 puts bar puts beans puts beans.one puts bar.one I had assumed that when I assigned bar to beans, it would create a copy of the object, and modifying one would not affect the other. Alas, the output shows otherwise. ^_^[jergason:~]$ ruby test.rb #<Foo:0x100155c60> #<Foo:0x100155c60> #<Foo:0x100155c60> #<Foo:0x100155c60> 2 2 I believe that the numbers have something to do with the address of the object, and they are the same for both beans and bar, and when I modify beans, bar gets changed as well, which is not what I had expected. It appears that I am only creating a pointer to the object, not a copy of it. What do I need to do to copy the object on assignment, instead of creating a pointer? Tests with the Array class shows some strange behavior as well. foo = [0, 1, 2, 3, 4, 5] baz = foo puts "foo is #{foo}" puts "baz is #{baz}" foo.pop puts "foo is #{foo}" puts "baz is #{baz}" foo += ["a hill of beans is a wonderful thing"] puts "foo is #{foo}" puts "baz is #{baz}" This produces the following wonky output: foo is 012345 baz is 012345 foo is 01234 baz is 01234 foo is 01234a hill of beans is a wonderful thing baz is 01234 This blows my mind. Calling pop on foo affects baz as well, so it isn't a copy, but concatenating something onto foo only affects foo, and not baz. So when am I dealing with the original object, and when am I dealing with a copy? In my own classes, how can I make sure that assignment copies, and doesn't make pointers? Help this confused guy out.

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