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• rapid application developement tools for very basic GUI apps

  - by Jurij

  I know there are many RAD platforms out there. Infact there are so many that I'm having a hard time finding out which one fits me best. What I want is a RAD tool that would allow me to define a database data model (make DB tables) and then create (view and edit) forms for the various tables. Data input, updating and various queries should be easy and GUI should generate automatically. I'd like to add some additional functionality by coding (such as various complex calculations on the data). I'm a programmer so I'm willing to learn to use a more complete, full-blown RAD solution if you can point me to it (NetBeans and RubyOnRails being the two such frameworks that I'd would probably be high on the list). I'm currently doing Windows Forms logistics apps in .NET. I've actually developed a very crude and basic version of what I need, but I just know that there are solutions out there that are much better and I'd benefit by knowing how to use them. So in short, the basic requirements: * database based data storage (SQLite if possible) * very automated GUI creation * desktop based (as in: not a web app) * extendable by coding * used for creating simple data entry, view & query apps. So basically something like Oracle Forms or DotNetMushroom Rapid Application Developer. But for .NET and SQLite if possible.

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• How does this Switch statement know which case to execute? (PHP/MySQL)

  - by ggfan

  Here is a code form a PHP+MySQL book I am reading and I am having trouble understanding this code. This code is about checking a file uploaded into a database. (Please excuse any spelling errors if any, I was typing it in) Q1: How does it know which case to echo? In the whole code, there is no mention of each case. Q2: Why do they skip case 5?! Or does it not matter which numbers you use(so I can have case 1, case 18, case 2?) if($_FILES['userfile']['error']>0) { echo 'Problem: '; switch($_FILES['userfile']['error']) { case 1: echo 'File exceeded upload_max_filesize'; break; case 2: echo 'File exceeded max_file_size'; break; case 3: echo 'File only partially uploaded'; break; case 4: echo 'No file uploaded'; break; case 6: echo 'Cannot upload file: no temp directory specified'; break; case 7: echo 'Upload failed: Cannot write to disk'; break; } exit; }

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• Code Golf: Morse code

  - by LiraNuna

  The challenge The shortest code by character count, that will input a string using only alphabetical characters (upper and lower case), numbers, commas, periods and question mark, and returns a representation of the string in Morse code. The Morse code output should consist of a dash (-, ascii 0x2D) for a long beep (aka 'dah') and a dot (., ascii 0x2E) for short beep (aka 'dit'). Each letter should be separated by a space (' ', ascii 0x20), and each word should be separated by a forward slash (/, ascii 0x2F). Morse code table: Test cases: Input: Hello world Output: .... . .-.. .-.. --- / .-- --- .-. .-.. -.. Input: Hello, Stackoverflow. Output: .... . .-.. .-.. --- --..-- / ... - .- -.-. -.- --- ...- . .-. ..-. .-.. --- .-- .-.-.- Code count includes input/output (i.e full program).

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• How does a java web project architecture look like without EJB3 ?

  - by Hendrik

  A friend and I are building a fairly complex website based on java. (PHP would have been more obvious but we chose for java because the educational aspect of this project is important to us) We have already decided to use JSF (with richfaces) for the front end and JPA for the backend and so far we have decided not to use EJB3 for the business layer. The reason we've decided not to use EJB3 is because - and please correct me if I am wrong - if we use EJB3 we can only run it on a full blown java application server like jboss and if we don't use EJB3 we can still run it on a lightweight server like tomcat. We want to keep speed and cost of our future web server in mind. So far i've worked on two JEE projects and both used the full stack with web business logic factories/persistence service entities with every layer a seperate module. Now here is my question, if you dont use EJB3 in the business logic layer. What does the layer look like? Please tell what is common practice when developing java web projects without ejb3? Do you think business logic layer can be thrown out altogether and have business logic in the backing beans? If you keep the layer, do you have all business methods static? Or do you initialize each business class as needed in the backing beans in every session as needed?

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• Angularjs: addition of integers even after I parse the variable as integer

  - by Shiv Kumar

  I really have a weird problem in adding two numbers. Here is my code, in the first controller everything is working fine, but in the second controller instead of 0 if I add 10, the output is completely weird Here is html code <div ng-app=""> <div ng-controller="Controller1"> <br/>**** Controller-1 <br/>Add 0 : {{update1(0)}} <br/>Add 10 : {{update1(10)}} <br/>Add 50 : {{update1(50)}} <br/>Add -60 : {{update1(-60)}}</div> <div ng-controller="Controller2"> <br/>**** Controller-2 <br/>Add 10 : {{update2(10)}} <br/>Add 10 : {{update2(10)}} <br/>Add 50 : {{update2(50)}} <br/>Add -60 : {{update2(-60)}}</div> </div> Here is my javascript function Controller1($scope) { var x = 0; $scope.update1 = function (smValue) { x += parseInt(smValue); return x; } } function Controller2($scope) { var y = 0; $scope.update2 = function (smValue) { y += parseInt(smValue); return y; } } and here is the output **** Controller-1 Add 0 : 0 Add 10 : 10 Add 50 : 60 Add -60 : 0 **** Controller-2 Add 0 : 110 Add 10 : 120 Add 50 : 170 Add -60 : 110 here is the link to try: http://jsfiddle.net/6VqqN/ can anyone please explain me why it is behaving like that. Even if I add a 3or4 digit number, output is completely different then what I expected.

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• LaTeX book class: Twosided document with wrong margins

  - by fgysin

  I am trying to write my thesis in latex... Cannot get the layout straight though :? I'm using the following document class: \documentclass[11pt,a4paper,twoside,openright]{book} My problem is: on the odd numbered pages there is a big margin right, and a small margin left - it should be the other way round... (for binding & stuff) I am a little puzzled by this - am I just to stupid to see the obvious? The odd page numbers appear on the 'right' page of a bound document, so there needs to be a larger margin left for bindin. Right? Why does LaTeX not behave like this? Here is the full code to produce a small Tex file that shows my problem: \documentclass[11pt,a4paper,twoside,openright]{book} \begin{document} \chapter{blah} Lorem ipsum ius et accumsan tractatos, aliquip deterruisset cu usu. Ea soleat eirmod nostrud eum, est ceteros similique ad, at mea tempor petentium. At decore neglegentur quo, ea ius doming dictas facilis, duo ut porro nostrum suavitate. \end{document}

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• Creating and publishing exel file in MOSS 2007 using data from SQL sever.

  - by Diomos

  Hello, I need help in this matter: We have a template of exel file in which all calculations are already set. User can request a 'report'. Idea is to create a button on our site (SharePoint portal). After clicking on it a new exel file is generated. This means to get actual data from database (SQL server 2005 SP2), import them into template, let all calculations to generate proper data and then allow user to see this file. For now it's enough to publish final exel file in document library. I am quite new in WSS 3.0 and MOSS 2007 and I need some advice in what can be the best solution. Looks like a quite complex task for me. Is there some direct way how to accomplish this? Or maybe I need one tool to get data from database and to import this data into exel file (SSRS?) and other tool to publish it in document library (MOSS7 Exel services?). I heard something about PerformancePoint Server 2007, is this a way to follow? Thanks forward for any advice!

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• Can someone look over the curriculum for this major & give me your thoughts? Computing & Security Te

  - by scottsharpejr

  My goal is to become a good web developer. I'm interested in learning how to build complex websites as well as how to write web applications. I want skills that will enable me to write apps for <--insert hottest web trend here-- (Facebook & iphone apps for example) This is one of my goals as far as Tech. is concerned. I'd also like to have a brod knowledge of different areas of IT. I'm looking into majoring in "Computing & Security Technology". The program is offered by Drexel in conjunction with my CC. It's a 4 year degree. Can someone take a look @ the pdf below. It outlines every course I must take. http://www.drexelatbcc.org/academics/PDF/CST_CT.pdf For degree requirments w/ links to course descriptiongs see drexel.edu/catalog/degree/ct.htm With electives I can go up to Web Development 4. Based on my goals of Web development & wanting a well rounding education in information technology, what do you think of the curriculum? How will I fare entering the job market with this degree? My goals here are a little different. I'd like to work for 2 to 3 companies over the course of 6-7 years. Working with and learning different areas of IT. I'd like to stay with a company an average of 2-3 years before moving on. My end goal is to go into business for myself (IT related). I appreciate any and all advice the community here can give me! :) Could someone also explain to me their interpretation of this major? thanks! P.S. I already know XHTML & CSS. I am just now starting to experiment with PHP.

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• How to scan an array for certain information

  - by Andrew Martin

  I've been doing an MSc Software Development conversion course, the main language of which is Java, since the end of September. We have our first assessed practical coming and I was hoping for some guidance. We have to create an array that will store 100 integers (all of which are between 1 and 10), which are generated by a random number generator, and then print out ten numbers of this array per line. For the second part, we need to scan these integers, count up how often each number appears and store the results in a second array. I've done the first bit okay, but I'm confused about how to do the second. I have been looking through the scanner class to see if it has any methods which I could use, but I don't see any. Could anyone point me in the right direction - not the answer, but perhaps which library it comes from? Code so far: import java.util.Random; public class Practical4_Assessed { public static void main(String[] args) { Random numberGenerator = new Random (); int[] arrayOfGenerator = new int[100]; for (int countOfGenerator = 0; countOfGenerator < 100; countOfGenerator++) arrayOfGenerator[countOfGenerator] = numberGenerator.nextInt(10); int countOfNumbersOnLine = 0; for (int countOfOutput = 0; countOfOutput < 100; countOfOutput++) { if (countOfNumbersOnLine == 10) { System.out.println(""); countOfNumbersOnLine = 0; countOfOutput--; } else { System.out.print(arrayOfGenerator[countOfOutput] + " "); countOfNumbersOnLine++; } } } } Thanks, Andrew

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• what exactly is the danger of an uninitialized pointer in C

  - by akh2103

  I am trying get a handle on C as I work my way thru Jim Trevor's "Cyclone: A safe dialect of C" for a PL class. Trevor and his co-authors are trying to make a safe version of C, so they eliminate uninitialized pointers in their language. Googling around a bit on uninitialized pointers, it seems like un-initialized pointers point to random locations in memory. It seems like this alone makes them unsafe. If you reference an un-itilialized pointer, you jump to an unsafe part of memory. Period. But the way Trevor talks about them seems to imply that it is more complex. He cites the following code, and explains that when the function FrmGetObjectIndex dereferences f, it isn’t accessing a valid pointer, but rather an unpredictable address — whatever was on the stack when the space for f was allocated. What does Trevor mean by "whatever was on the stack when the space for f was allocated"? Are "un-initialized" pointers initialized to random locations in memory by default? Or does their "random" behavior have to do with the memory allocated for these pointers getting filled with strange values (that are then referenced) because of unexpected behavior on the stack. Form *f; switch (event->eType) { case frmOpenEvent: f = FrmGetActiveForm(); ... case ctlSelectEvent: i = FrmGetObjectIndex(f, field); ... }

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• CLR Stored Procedures

  - by Paul Hatcherian

  In an ASP.NET application, I have a small number of fairly complex, frequently used operations to execute against a database. In these operations, one or more of several tables needs updates or inserts based a logical evaluation of both input parameters and values of certain tables. I've maintained a separation of logic and data access, so the operation currently looks like this: Request received from client Business layer invokes data layer to retrieve data from database Business layer processes result and determines which operation to execute Business layer invokes appropriate data operation Response sent to client As you can see, the client is kept waiting while two separate requests are made to the database. In searching for a solution to this, I've found CLR Stored Procedures, but I'm not sure if I have the right idea about what they are useful for. I have written a replacement for the code above which especially places steps 2-4 in a CLR SP. My understanding is that the SP will be executed locally by SQL Server and result in only one call being made to the server. My initial benchmark tests show this is actually orders of magnitude slower than my original code, but I attribute that recompilation of the code I have not worked out yet and/or some flaw in my environment. My question is basically, is this the intended use of CLR SPs or am I missing something? I realize this is a bit of a compromise structurally, so if there's a better way to do it I'd love to hear it.

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• How to arrange business logic in a Kohana 3 project

  - by Pekka

  I'm looking for advice, tutorials and links at how to set up a mid-sized web application with Kohana 3. I have implemented MVC patterns in the past but never worked against a "formalized" MVC framework so I'm still getting my head around the terminology - toying around with basic examples, building views and templates, and so on. I'm progressing fairly well but I want to set up a real-world web project (one of my own that I've been planning for quite some time now) as a learning object. I learn best by example, but example-based documentation is a bit sparse for Kohana 3 right now - they say so themselves on the site. While I'm not worried about learning the framework as I go along, I want to make sure the code base is healthily structured from the start - i.e. controllers are split nicely, named well and according to standards, and most importantly the business logic is separated into appropriately sized models. My application could, in its core, be described as a business directory with a range of search and listing functions, and a login area for each entry owner. The actual administrative database backend is already taken care of. Supposing I have all the API worked out and in place already - list all businesses, edit business, list businesses by street name, create offer logged in as business, and so on, and I'm just looking for how to fit the functionality into a MVC pattern and into a Kohana application structure that can be easily extended. Do you know real-life examples of "database-heavy" applications like directories, online communities... with a log-in area built on Kohana 3, preferably Open Source so I could take a peek how they do it? Are there conventions or best practices on how to structure an extendable login area for end users in a Kohana project that is not only able to handle a business directory page, but further products on separate pages as well? Do you know any good resources on building complex applications with Kohana? Have you built something similar and could give me recommendations on a project structure?

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• Is it immoral to write crappy code even if readability and correctness is not a requirement?

  - by mafutrct

  There are cases when crappy (i.e. unreadable and buggy) code is not much of a problem. For instance, imagine you need to generate a big text file that mostly follows a simple pattern with a few very complex exceptions. What do you do? You quickly write a simple algorithm and insert the exceptional bits in the output manually to save 4 hours. The code is unreadable, and the output is flawed, but it's still the correct way since it is way faster. But let's get this straight: I hate bad code. I've had to read and work with code that caused my stomach to hurt. I care a lot about good code. And actually, I caught myself thinking that it is immoral to write bad code even though the dirty approach is sometimes superior. I was surprised by myself and found my idea to be very irrational. Did you ever experience this? Should I just get rid of this stupid idea and use the most efficient approach to coding?

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• .NET regex: Match.nextMatch() never returns

  - by Jimmy

  I have a regex that seems to have worked fine for the past year or so, and all of a sudden today with a new slightly different text to match against, Match.nextMatch() never returns. I'm no regex expert and I'm sure the regex can be optimized, but previous data sets weren't much more complex than what I've tried today. Furthermore, the regex works fine against the offending data set in a tool like RegexBuddy; it's only in .net (running in debug in Visual Studio) that it seems to hang. Nevertheless, if anyone can figure out how to tweak the regex to make it work, I'd really appreciate it. This is the regex: <tr>(<td[^>]*><a[^>]*>(?<callOptionTicker>[A-Z]{1,5}\d{6}C\d{8})</a></td>)(<td[^>]*>.*?</td>){6}(<td[^>]*><b><a[^>]*>(?<strikePrice>\d*\.\d*)</a></b></td>)(<td[^>]*><a[^>]*>(?<putOptionTicker>[A-Z]{1,5}\d{6}P\d{8})</a></td>) It's meant to extract put and call option tickers from a Yahoo option chain page (i.e., raw HTML). It works fine for IBM http://finance.yahoo.com/q/os?s=IBM&m=2010-05-21 It doesn't work for SPX options (this is the offending data set) http://finance.yahoo.com/q/os?s=I:SPX.W&m=2010-05

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• DataTable vs. Collection in .Net

  - by B Pete

  I am writing a program that needs to read a set of records that describe the register map of a device I need to communicate with. Each record will have a handfull of fields that describe the properties of each register. I don't really need to edit or modify the data in my VB or C# program, though I would like to be able to display the data on a grid. I would like to store the data in a CSV file, or perhaps an XML file. I need to enable users to edit the data off-line, preferably in excel. I am considering using a DataTable or a Collection of "Register" objects (which I would define). I prototyped a DataTable, and found I can read/write XML easily using the built in methods and I can easily bind to a DataGridView. I was not able to find a way to retreive info on a single register without using a query that returns a collection of rows, even though I defined a unique primaty key column. The syntax to get a value from a column is also complex, though I could be missing something on both counts. I'm tempted to use a collection of "Register" objects that I can access via a unique key. It would be a little more coding up front, but seems like a cleaner solution overall. I should still be able to use LINQ to dataset to query subsets of registers when I need them, but would also be able to grab a single field using a the key value, something like this: Registers(keyValue).fieldName). Which would be a cleaner approach to the problem? Is there a way to read/write XML into a Collection without needing custom code? Could this be accomplished using String for a key?

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• Why does my ActivePerl program report 'Sorry. Ran out of threads'?

  - by Zaid

  Tom Christiansen's example code (à la perlthrtut) is a recursive, threaded implementation of finding and printing all prime numbers between 3 and 1000. Below is a mildly adapted version of the script #!/usr/bin/perl # adapted from prime-pthread, courtesy of Tom Christiansen use strict; use warnings; use threads; use Thread::Queue; sub check_prime { my ($upstream,$cur_prime) = @_; my $child; my $downstream = Thread::Queue->new; while (my $num = $upstream->dequeue) { next unless ($num % $cur_prime); if ($child) { $downstream->enqueue($num); } else { $child = threads->create(\&check_prime, $downstream, $num); if ($child) { print "This is thread ",$child->tid,". Found prime: $num\n"; } else { warn "Sorry. Ran out of threads.\n"; last; } } } if ($child) { $downstream->enqueue(undef); $child->join; } } my $stream = Thread::Queue->new(3..shift,undef); check_prime($stream,2); When run on my machine (under ActiveState & Win32), the code was capable of spawning only 118 threads (last prime number found: 653) before terminating with a 'Sorry. Ran out of threads' warning. In trying to figure out why I was limited to the number of threads I could create, I replaced the use threads; line with use threads (stack_size => 1);. The resultant code happily dealt with churning out 2000+ threads. Can anyone explain this behavior?

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• C# Using Enumerable Range and Except with custom class to determine missing sequence number

  - by Jon

  I have a List<MyClass> The class is like this: private class MyClass { public string Name{ get; set; } public int SequenceNumber { get; set; } } I want to work out what Sequence numbers might be missing. I can see how to do this here however because this is a class I am unsure what to do? I think I can handle the except method ok with my own IComparer but the Range method I can't figure out because it only excepts int so this doesn't compile: Enumerable.Range(0, 1000000).Except(chqList, MyEqualityComparer<MyClass>); Here is the IComparer: public class MyEqualityComparer<T> : IEqualityComparer<T> where T : MyClass { #region IEqualityComparer<T> Members public bool Equals(T x, T y) { return (x == null && y == null) || (x != null && y != null && x.SequenceNumber.Equals(y.SequenceNumber)); } /// </exception> public int GetHashCode(T obj) { if (obj == null) { throw new ArgumentNullException("obj"); } return obj.GetHashCode(); } #endregion }

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• Performance of java on different hardware?

  - by tangens

  In another SO question I asked why my java programs run faster on AMD than on Intel machines. But it seems that I'm the only one who has observed this. Now I would like to invite you to share the numbers of your local java performance with the SO community. I observed a big performance difference when watching the startup of JBoss on different hardware, so I set this program as the base for this comparison. For participation please download JBoss 5.1.0.GA and run: jboss-5.1.0.GA/bin/run.sh (or run.bat) This starts a standard configuration of JBoss without any extra applications. Then look for the last line of the start procedure which looks like this: [ServerImpl] JBoss (Microcontainer) [5.1.0.GA (build: SVNTag=JBoss_5_1_0_GA date=200905221634)] Started in 25s:264ms Please repeat this procedure until the printed time is somewhat stable and post this line together with some comments on your hardware (I used cpu-z to get the infos) and operating system like this: java version: 1.6.0_13 OS: Windows XP Board: ASUS M4A78T-E Processor: AMD Phenom II X3 720, 2.8 GHz RAM: 2*2 GB DDR3 (labeled 1333 MHz) GPU: NVIDIA GeForce 9400 GT disc: Seagate 1.5 TB (ST31500341AS) Use your votes to bring the fastest configuration to the top. I'm very curious about the results. EDIT: Up to now only a few members have shared their results. I'd really be interested in the results obtained with some other architectures. If someone works with a MAC (desktop) or runs an Intel i7 with less than 3 GHz, please once start JBoss and share your results. It will only take a few minutes.

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• Function that prints something to std::ostream and returns std::ostream?

  - by dehmann

  I want to write a function that outputs something to a ostream that's passed in, and return the stream, like this: std::ostream& MyPrint(int val, std::ostream* out) { *out << val; return *out; } int main(int argc, char** argv){ std::cout << "Value: " << MyPrint(12, &std::cout) << std::endl; return 0; } It would be convenient to print the value like this and embed the function call in the output operator chain, like I did in main(). It doesn't work, however, and prints this: $ ./a.out 12Value: 0x6013a8 The desired output would be this: Value: 12 How can I fix this? Do I have to define an operator<< instead? UPDATE: Clarified what the desired output would be. UPDATE2: Some people didn't understand why I would print a number like that, using a function instead of printing it directly. This is a simplified example, and in reality the function prints a complex object rather than an int.

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• Tips on managing dependencies for a release?

  - by Andrew Murray

  Our system comprises many .NET websites, class libraries, and a MSSQL database. We use SVN for source control and TeamCity to automatically build to a Test server. Our team is normally working on 4 or 5 projects at a time. We try to lump many changes into a largish rollout every 2-4 weeks. My problem is with keeping track of all the dependencies for a rollout. Example: Website A cannot go live until we've rolled out Branch X of Class library B, built in turn against the Trunk of Class library C, which needs Config Updates Y and Z and Database Update D, which needs Migration Script E... It gets even more complex - like making sure each developer's project is actually compatible with the others and are building against the same versions. Yes, this is a management issue as much as a technical issue. Currently our non-optimal solution is: a whiteboard listing features that haven't gone live yet relying on our memory and intuition when planning the rollout, until we're pretty sure we've thought of everything... a dry-run on our Staging environment. It's a good indication but we're often not sure if Staging is 100% in sync with Live - part of the problem I'm hoping to solve. some amount of winging it on rollout day. So far so good, minus a few close calls. But as our system grows, I'd like a more scientific release management system allowing for more flexibility, like being able to roll out a single change or bugfix on it's own, safe in the knowledge that it won't break anything else. I'm guessing the best solution involves some sort of version numbering system, and perhaps using a project management tool. We're a start-up, so we're not too hot on religiously sticking to rigid processes, but we're happy to start, providing it doesn't add more overhead than it's worth. I'd love to hear advice from other teams who have solved this problem.

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• how to manage a "resource" array efficiently

  - by Haiyuan Zhang

  The senario of my question is that one need to use a fixed size of array to keep track of certain number of "objects" . The object here can be as simply as a integer or as complex as very fancy data structure. And "keep track" here means to allocate one object when other part of the app need one instance of object and recyle it for future allocation when one instance of the object is returned .Finally ,let me use c++ to put my problme in a more descriptive way . #define MAX 65535 /* 65535 just indicate that many items should be handled . performance demanding! */ typedef struct { int item ; }Item_t; Item_t items[MAX] ; class itemManager { private : /* up to you.... */ public : int get() ; /* get one index to a free Item_t in items */ bool put(int index) ; /* recyle one Item_t indicate by one index in items */ } how will you implement the two public functions of itemManager ? it's up to you to add any private member .

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• average case running time of linear search algorithm

  - by Brahadeesh

  Hi all. I am trying to derive the average case running time for deterministic linear search algorithm. The algorithm searches an element x in an unsorted array A in the order A[1], A[2], A[3]...A[n]. It stops when it finds the element x or proceeds until it reaches the end of the array. I searched on wikipedia and the answer given was (n+1)/(k+1) where k is the number of times x is present in the array. I approached in another way and am getting a different answer. Can anyone please give me the correct proof and also let me know whats wrong with my method? E(T)= 1*P(1) + 2*P(2) + 3*P(3) ....+ n*P(n) where P(i) is the probability that the algorithm runs for 'i' time (i.e. compares 'i' elements). P(i)= (n-i)C(k-1) * (n-k)! / n! Here, (n-i)C(k-1) is (n-i) Choose (k-1). As the algorithm has reached the ith step, the rest of k-1 x's must be in the last n-i elements. Hence (n-i)C(k-i). (n-k)! is the total number of ways of arranging the rest non x numbers, and n! is the total number of ways of arranging the n elements in the array. I am not getting (n+1)/(k+1) on simplifying.

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• Simple in-place discrete fourier transform ( DFT )

  - by Adam

  I'm writing a very simple in-place DFT. I am using the formula shown here: http://en.wikipedia.org/wiki/Discrete_Fourier_transform#Definition along with Euler's formula to avoid having to use a complex number class just for this. So far I have this: private void fft(double[] data) { double[] real = new double[256]; double[] imag = new double[256]; double pi_div_128 = -1 * Math.PI / 128; for (int k = 0; k < 256; k++) { for (int n = 0; n < 256; n++) { real[k] += data[k] * Math.Cos(pi_div_128 * k * n); imag[k] += data[k] * Math.Sin(pi_div_128 * k * n); } data[k] = Math.Sqrt(real[k] * real[k] + imag[k] * imag[k]); } } But the Math.Cos and Math.Sin terms eventually go both positive and negative, so as I'm adding those terms multiplied with data[k], they cancel out and I just get some obscenely small value. I see how it is happening, but I can't make sense of how my code is perhaps mis-representing the mathematics. Any help is appreciated. FYI, I do have to write my own, I realize I can get off-the shelf FFT's.

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• Cladogram, tree of life, cladistics, taxonomy in JS or canvas?

  - by boblet

  Good people - I need some help to find a way to create an interactive cladogram or phylogenetic tree (yes, I have read all related posts, and do not find what I am looking for). The thing is, I need the nodes to be name-able. An example would be something like this Most scripts I find are either applets, flash, or simply do not show the node classification, ie it would skip "feliformia" in this example. This is useless to me, as I would then end up with carnivore - anonymous node - anonymous node - anonymous node - tiger, and that is not good. This tree will in theory cover all life, so it could get rather large, and get links and names in english and latin from database. So: no flash, no applets. It must be horizontal, no supertrees (circular). I have gone through this http://bioinfo.unice.fr/biodiv/Tree_editors.html but most of them seems to be either old, not displaying sub-node levels, applets, or way too complex. I imagine this would be a delightful job for canvas/jQuery..? And chances are, someone got there before me? Any pointers much appreciated. Note: if anyone out there would like to do something like this as a project, I will be happy to help, even though it would not benefit me for this project.This type of taxonomy is not as simple as it may seem, and I would be happy see this happen.

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• Why This Maintainability Index Increase?

  - by Timothy

  I would be appreciative if someone could explain to me the difference between the following two pieces of code in terms of Visual Studio's Code Metrics rules. Why does the Maintainability Index increase slightly if I don't encapsulate everything within using ( )? Sample 1 (MI score of 71) public static String Sha1(String plainText) { using (SHA1Managed sha1 = new SHA1Managed()) { Byte[] text = Encoding.Unicode.GetBytes(plainText); Byte[] hashBytes = sha1.ComputeHash(text); return Convert.ToBase64String(hashBytes); } } Sample 2 (MI score of 73) public static String Sha1(String plainText) { Byte[] text, hashBytes; using (SHA1Managed sha1 = new SHA1Managed()) { text = Encoding.Unicode.GetBytes(plainText); hashBytes = sha1.ComputeHash(text); } return Convert.ToBase64String(hashBytes); } I understand metrics are meaningless outside of a broader context and understanding, and programmers should exercise discretion. While I could boost the score up to 76 with return Convert.ToBase64String(sha1.ComputeHash(Encoding.Unicode.GetBytes(plainText))), I shouldn't. I would clearly be just playing with numbers and it isn't truly any more readable or maintainable at that point. I am curious though as to what the logic might be behind the increase in this case. It's obviously not line-count.

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