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  • Is it safe to use random Unicode for complex delimiter sequences in strings?

    - by ccomet
    Question: In terms of program stability and ensuring that the system will actually operate, how safe is it to use chars like ¦, § or ‡ for complex delimiter sequences in strings? Can I reliable believe that I won't run into any issues in a program reading these incorrectly? I am working in a system, using C# code, in which I have to store a fairly complex set of information within a single string. The readability of this string is only necessary on the computer side, end-users should only ever see the information after it has been parsed by the appropriate methods. Because some of the data in these strings will be collections of variable size, I use different delimiters to identify what parts of the string correspond to a certain tier of organization. There are enough cases that the standard sets of ;, |, and similar ilk have been exhausted. I considered two-char delimiters, like ;# or ;|, but I felt that it would be very inefficient. There probably isn't that large of a performance difference in storing with one char versus two chars, but when I have the option of picking the smaller option, it just feels wrong to pick the larger one. So finally, I considered using the set of characters like the double dagger and section. They only take up one char, and they are definitely not going to show up in the actual text that I'll be storing, so they won't be confused for anything. But character encoding is finicky. While the visibility to the end user is meaningless (since they, in fact, won't see it), I became recently concerned about how the programs in the system will read it. The string is stored in one database, while a separate program is responsible for both encoding and decoding the string into different object types for the rest of the application to work with. And if something is expected to be written one way, is possibly written another, then maybe the whole system will fail and I can't really let that happen. So is it safe to use these kind of chars for background delimiters?

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  • Running Solr on VPS problems

    - by Camran
    I have a VPS with Ubuntu OS. I run solr om my local machine (windows xp laptop) just fine. I have configured Jetty, and Solr just the same way as on my computer, but on the server. I have also downloaded the JRE and installed it on the server. However, whenever I try to run the start.jar file, the PuTTY terminal shows a bunch of text but gets stuck. I could pase the text here but it is very long, so unless somebody wants to see it I wont. Also, I cant view the solr admin page at all. Does anybody have experience in this kind of problem? Maybe java isn't correctly installed? It is a VPS so maybe installation is different. Thanks UPDATE: These are the last lines from the terminal, in other words, this is where it stops every time: INFO: [] webapp=null path=null params={event=firstSearcher&q=static+firstSearcher+warming+query+from+solrconfig.xml} hits=0 status=0 QTime=9 May 28, 2010 8:58:42 PM org.apache.solr.core.QuerySenderListener newSearcher INFO: QuerySenderListener done. May 28, 2010 8:58:42 PM org.apache.solr.handler.component.SpellCheckComponent$SpellCheckerListener newSearcher INFO: Loading spell index for spellchecker: default May 28, 2010 8:58:42 PM org.apache.solr.core.SolrCore registerSearcher INFO: [] Registered new searcher Searcher@63a721 main

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  • Inheritance issue with ivar on the iPhone

    - by Buffalo
    I am using the BLIP/MYNetwork library to establish a basic tcp socket connection between the iPhone and my computer. So far, the code builds and runs correctly in simulator but deploying to device yields the following error: error: property 'delegate' attempting to use ivar '_delegate' declared in super class of 'TCPConnection' @interface TCPConnection : TCPEndpoint { @private TCPListener *_server; IPAddress *_address; BOOL _isIncoming, _checkedPeerCert; TCPConnectionStatus _status; TCPReader *_reader; TCPWriter *_writer; NSError *_error; NSTimeInterval _openTimeout; } /** The delegate object that will be called when the connection opens, closes or receives messages. */ @property (assign) id<TCPConnectionDelegate> delegate; /** The delegate messages sent by TCPConnection. All methods are optional. */ @protocol TCPConnectionDelegate <NSObject> @optional /** Called after the connection successfully opens. */ - (void) connectionDidOpen: (TCPConnection*)connection; /** Called after the connection fails to open due to an error. */ - (void) connection: (TCPConnection*)connection failedToOpen: (NSError*)error; /** Called when the identity of the peer is known, if using an SSL connection and the SSL settings say to check the peer's certificate. This happens, if at all, after the -connectionDidOpen: call. */ - (BOOL) connection: (TCPConnection*)connection authorizeSSLPeer: (SecCertificateRef)peerCert; /** Called after the connection closes. You can check the connection's error property to see if it was normal or abnormal. */ - (void) connectionDidClose: (TCPConnection*)connection; @end @interface TCPEndpoint : NSObject { NSMutableDictionary *_sslProperties; id _delegate; } - (void) tellDelegate: (SEL)selector withObject: (id)param; @end Does anyone know how I would fix this? Would I simply declare _delegate as a public property of the base class "TCPEndPoint"? Thanks for the help ya'll!

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  • Practical rules for premature optimization

    - by DougW
    It seems that the phrase "Premature Optimization" is the buzz-word of the day. For some reason, iphone programmers in particular seem to think of avoiding premature optimization as a pro-active goal, rather than the natural result of simply avoiding distraction. The problem is, the term is beginning to be applied more and more to cases that are completely inappropriate. For example, I've seen a growing number of people say not to worry about the complexity of an algorithm, because that's premature optimization (eg http://stackoverflow.com/questions/2190275/help-sorting-an-nsarray-across-two-properties-with-nssortdescriptor/2191720#2191720). Frankly, I think this is just laziness, and appalling to disciplined computer science. But it has occurred to me that maybe considering the complexity and performance of algorithms is going the way of assembly loop unrolling, and other optimization techniques that are now considered unnecessary. What do you think? Are we at the point now where deciding between an O(n^n) and O(n!) complexity algorithm is irrelevant? What about O(n) vs O(n*n)? What do you consider "premature optimization"? What practical rules do you use to consciously or unconsciously avoid it? This is a bit vague, but I'm curious to hear other peoples' opinions on the topic.

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  • Hidden div height

    - by fudgey
    Ok, I was going to answer someone's question here on SO about why their script wasn't working. They loaded content into a hidden div, then got the height so they could animate the wrapping div. But I always try to test the code I provide. So I made this demo to prove it to them. So, umm, have I entered the twilight zone or am I dreaming right now? pinches self OUCH! I tried that demo in Firefox, IE and Chrome and both methods return the same value. Firebug says zero! I rebooted my computer and I even changed the code a bit (removed the height function) and tried it with jQuery 1.3.2 and it still worked! I know hidden elements USED to return a zero value. Even this SO Answer is giving the advice I would have! So I guess my question is... did I miss something or are we giving bad advice?

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  • Can you recommend a full-text search engine?

    - by Jen
    Can you recommend a full-text search engine? (Preferably open source) I have a database of many (though relatively short) HTML documents. I want users to be able to search this database by entering one or more search words in my C++ desktop application. Hence, I’m looking for a fast full-text search solution to integrate with my app. Ideally, it should: Skip common words, such as the, of, and, etc. Support stemming, i.e. search for run also finds documents containing runner, running and ran. Be able to update its index in the background as new documents are added to the database. Be able to provide search word suggestions (like Google Suggest) Have a well-documented API To illustrate, assume the database has just two documents: Document 1: This is a test of text search. Document 2: Testing is fun. The following words should be in the index: fun, search, test, testing, text. If the user types t in the search box, I want the application to be able to suggest test, testing and text (Ideally, the application should be able to query the search engine for the 10 most common search words starting with t). A search for testing should return both documents. Other points: I don't need multi-user support I don't need support for complex queries The database resides on the user's computer, so the indexing should be performed locally. Can you suggest a C or C++ based solution? (I’ve briefly reviewed CLucene and Xapian, but I’m not sure if either will address my needs, especially querying the search word indexes for the suggest feature).

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  • How do I design a Wizard-based system with SoC in mind?

    - by Erik Forbes
    I'm building a Windows Forms system (in C# if it matters to anyone) that provides an application automation service. As this application is targeted at users who are not computer savvy, I've decided to break up the functions of the application into various tasks, and provide these tasks via a wizard UI. I'd like to avoid coupling the views and view engine (from which the Wizard will be built) to the automation engine. The problem I'm having is that the automation engine, which runs on a separate thread while it does its thing, needs to report status information back to the user, as well as listen for cancel or pause events from the user. Since I don't want the view engine or the automation engine to rely on each other, I'm having a hard time figuring out how to provide for this information conduit. Any insights into this issue I'm having would be greatly appreciated. I've been wracking my brain for a couple weeks now on this point, and I really don't want to give up and just couple everything together. If anyone needs additional details to help come up with some sort of idea please let me know and I'll be happy to provide them.

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  • multi-core processing in R on windows XP - via doMC and foreach

    - by Jan
    Hi guys, I'm posting this question to ask for advice on how to optimize the use of multiple processors from R on a Windows XP machine. At the moment I'm creating 4 scripts (each script with e.g. for (i in 1:100) and (i in 101:200), etc) which I run in 4 different R sessions at the same time. This seems to use all the available cpu. I however would like to do this a bit more efficient. One solution could be to use the "doMC" and the "foreach" package but this is not possible in R on a Windows machine. e.g. library("foreach") library("strucchange") library("doMC") # would this be possible on a windows machine? registerDoMC(2) # for a computer with two cores (processors) ## Nile data with one breakpoint: the annual flows drop in 1898 ## because the first Ashwan dam was built data("Nile") plot(Nile) ## F statistics indicate one breakpoint fs.nile <- Fstats(Nile ~ 1) plot(fs.nile) breakpoints(fs.nile) # , hpc = "foreach" --> It would be great to test this. lines(breakpoints(fs.nile)) Any solutions or advice? Thanks, Jan

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  • Database frontend for multiple db engines

    - by xeroxed_yeti
    Hey Stackoverflow, yeah it's spring and a lot of things happens to me... Also changing some software things at my computer, because suddenly everything seems to be boring after starting my laptop. I even changed my wallpaper!!! Besides I'm looking for a new database frontend and after using google with serveral queries I didn't find the right software. You have to know, my laptop and me are very very special :) I'm looking for a database frontend which should have following features can access PostgreSQL and MySQL databases can handle schemata overs a nice sql query tool supports an import and export functionality (something like tab separated text files) it for free looks awesome - every time when a college come to my office he must get the feeling: oh boy, this man really knows his job and should get more money! At the moment I used phpmyadmin, phppgadmin, pgadminIII, mysqladmin and dbVisualizer. Furthermore I was a big fan of the aqua datastudio until it became commercial. This tools offers a great variety of functionalities which can simplify programmes live. However, now you have to buy a license...I'm a scientist and money for software is limited =) So it's my first time (question) here at stackoverflow please be cheerful :)

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  • Why is this attempt at a binary search crashing?

    - by Ian Campbell
    I am fairly new to the concept of a binary search, and am trying to write a program that does this in Java for personal practice. I understand the concept of this well, but my code is not working. There is a run-time exception happening in my code that just caused Eclipse, and then my computer, to crash... there are no compile-time errors here though. Here is what I have so far: public class BinarySearch { // instance variables int[] arr; int iterations; // constructor public BinarySearch(int[] arr) { this.arr = arr; iterations = 0; } // instance method public int findTarget(int targ, int[] sorted) { int firstIndex = 1; int lastIndex = sorted.length; int middleIndex = (firstIndex + lastIndex) / 2; int result = sorted[middleIndex - 1]; while(result != targ) { if(result > targ) { firstIndex = middleIndex + 1; middleIndex = (firstIndex + lastIndex) / 2; result = sorted[middleIndex - 1]; iterations++; } else { lastIndex = middleIndex + 1; middleIndex = (firstIndex + lastIndex) / 2; result = sorted[middleIndex - 1]; iterations++; } } return result; } // main method public static void main(String[] args) { int[] sortedArr = new int[] { 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29 }; BinarySearch obj = new BinarySearch(sortedArr); int target = sortedArr[8]; int result = obj.findTarget(target, sortedArr); System.out.println("The original target was -- " + target + ".\n" + "The result found was -- " + result + ".\n" + "This took " + obj.iterations + " iterations to find."); } // end of main method } // end of class BinarySearch

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  • Limiting ssh user account only to access his home directory!

    - by EBAGHAKI
    By reading some tutorials online I used these commands: Make a local group: net localgroup CopsshUsers /ADD Deny access to this group at top level: cacls c:\ /c /e /t /d CopsshUsers Open access to the copSSH installation directory: cacls copssh-inst-dir /c /e /t /r CopsshUsers Add Copssh user to the group above: net localgroup CopsshUsers mysshuser /add simply put these commands will try to create a usergroup that has no permission on your computer and it only have access to the copSSH Installation directory. This is not true, since you cannot change the permission on your windows directory, the third command won't remove access to windows folder (it says access denied on his log). Somehow I achieved that by taking ownership of Windows folder and then i execute the third command so CopsshUsers has no permissions on windows folder from now on. Now i tried to SSH to the server and it simply can't login! this is kind of funny because with permission on windows directory you can login and without it you can't!! So if you CAN SSH to the server somehow you know that you have access to the windows directory! (Is this really true??) Simple task: Limiting ssh user account only to access his home directory on WINDOWS and nothing else! Guys please help!

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  • How can we serialize a class that is not a custom class of our own?

    - by Doug
    I need to look at the properties of an object and I cannot instantiate this object in the proper state on my dev machine. I need my client to run some code on her machine, serialize the object in question to disk and then I can analyze the file. Here is the class I want to serialize. System.Security.AccessControl.RegistrySecurity Here is my code: Private Sub SerializeRegSecurity(ByVal regKey As RegistryKey) Try Dim regSecurity As System.Security.AccessControl.RegistrySecurity = regKey.GetAccessControl() Dim oXS As XmlSerializer = New XmlSerializer(GetType(System.Security.AccessControl.RegistrySecurity)) Dim oStmW As StreamWriter Dim regDebugFilePath As String = Path.Combine(My.Computer.FileSystem.SpecialDirectories.Desktop, "RegDebugFile.xml") 'Serialize object to XML and write it to XML file oStmW = New StreamWriter(regDebugFilePath) oXS.Serialize(oStmW, regSecurity) oStmW.Close() Catch ex As Exception Console.WriteLine(ex.ToString) End Try End Sub And here's what I end up with in my XML file: <?xml version="1.0" encoding="utf-8"?> Any ideas on how to accomplish what I am trying to do? How can we serialize a class that is not a custom class of our own? Thanks for ANY help. Even an alternate method.

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  • What are the worst examples of moral failure in the history of software engineering?

    - by Amanda S
    Many computer science curricula include a class or at least a lecture on disasters caused by software bugs, such as the Therac-25 incidents or Ariane 5 Flight 501. Indeed, Wikipedia has a list of software bugs with serious consequences, and a question on StackOverflow addresses some of them too. We study the failures of the past so that we don't repeat them, and I believe that rather than ignoring them or excusing them, it's important to look at these failures squarely and remind ourselves exactly how the mistakes made by people in our profession cost real money and real lives. By studying failures caused by uncaught bugs and bad process, we learn certain lessons about rigorous testing and accountability, and we make sure that our innocent mistakes are caught before they cause major problems. There are kinds of less innocent failure in software engineering, however, and I think it's just as important to study the serious consequences caused by programmers motivated by malice, greed, or just plain amorality. Thus we can learn about the ethical questions that arise in our profession, and how to respond when we are faced with them ourselves. Unfortunately, it's much harder to find lists of these failures--the only one I can come up with is that apocryphal "DOS ain't done 'til Lotus won't run" story. What are the worst examples of moral failure in the history of software engineering?

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  • OS X: Terminal output of javac is garbled.

    - by Don Werve
    I've got my computer set up in Japanese (hey, it's good language practice), and everything is all fine and dandy... except javac. It displays localized error messages out to the console, but they're in Shift-JIS, not UTF8: $ javac this-file-doesnt-exist.java javac: ?t?@?C??????????????: this-file-doesnt-exist.java ?g????: javac <options> <source files> ?g?p?\??I?v?V?????~??X?g?????A-help ???g?p???? If I pipe the output through nkf -w, it's readable, but that's not really much of a solution: $ javac this-file-doesnt-exist.java 2>&1 | nkf -w javac: ????????????: this-file-doesnt-exist.java ???: javac <options> <source files> ????????????????????-help ?????? Everything else works fine (with UTF8) from the command-line; I can type filenames in Japanese, tab-completion works fine, vi can edit UTF-8 files, etc. Although java itself spits out all its messages in English (which is fine). Here's the relevant bits of my environment: LC_CTYPE=UTF-8 LANG=ja_JP.UTF-8 From what it looks like, javac isn't picking up the encoding properly, and java isn't picking up the language at all. I've tried -Dfile.encoding=utf8 as well, but that does nada, and documentation on the localization of the JVM toolchain is pretty nonexistent, at least from Google.

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  • Wondering where to begin

    - by Cat
    Hello all. After being interested for years and years (and years), I have finally decided to start learning how to create software and web applications. Base on recommendations, I have started with learning the basics of web design first (which I am almost done with) and then will move on to the meat of my process: learning the languages. Problem is, I don't know where to start :/ PHP, Ruby, Perl...and where would SQL, JavaScript and .NET fit into the mix? I am assuming they build on each other/play off of each other somewhat so following some sort of 'order' will make the process more logical and digestible. You're probably thinking, "Just go to school for computer engineering, duh!" But I already have a degree and don't plan on going back to school. I believe I have an adequate aptitude for this sort of thing, and although it will be challenging, with the support of the community I know I can do it on my own. Thank in advance everyone and I am very sorry for the length. I look forward to hearing what all you have to say. Warm Regards, Cat

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  • Given 4 objects, how to figure out whether exactly 2 have a certain property

    - by Cocorico
    Hi guys! I have another question on how to make most elegant solution to this problem, since I cannot afford to go to computer school right so my actual "pure programming" CS knowledge is not perfect or great. This is basically an algorhythm problem (someone please correct me if I am using that wrong, since I don't want to keep saying them and embarass myself) I have 4 objects. Each of them has an species property that can either be a dog, cat, pig or monkey. So a sample situation could be: object1.species=pig object2.species=cat object3.species=pig object4.species=dog Now, if I want to figure out if all 4 are the same species, I know I could just say: if ( (object1.species==object2.species) && (object2.species==object3.species) && (object3.species==object4.species) ) { // They are all the same animal (don't care WHICH animal they are) } But that isn't so elegant right? And if I suddenly want to know if EXACTLY 3 or 2 of them are the same species (don't care WHICH species it is though), suddenly I'm in spaghetti code. I am using Objective C although I don't know if that matters really, since the most elegant solution to this is I assume the same in all languages conceptually? Anyone got good idea? Thanks!!

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  • Is this a good job description? What title would you give this position?

    - by Zack Peterson
    Department: Information Technology Reports To: Chief Information Officer Purpose: Company's ________________ is specifically engaged in the development of World Wide Web applications and distributed network applications. This person is concerned with all facets of the software development process and specializes in software product management. He or she contributes to projects in an application architect role and also performs individual programming tasks. Essential Duties & Responsibilities: This person is involved in all aspects of the software development process such as: Participation in software product definitions, including requirements analysis and specification Development and refinement of simulations or prototypes to confirm requirements Feasibility and cost-benefit analysis, including the choice of architecture and framework Application and database design Implementation (e.g. installation, configuration, customization, integration, data migration) Authoring of documentation needed by users and partners Testing, including defining/supporting acceptance testing and gathering feedback from pre-release testers Participation in software release and post-release activities, including support for product launch evangelism (e.g. developing demonstrations and/or samples) and subsequent product build/release cycles Maintenance Qualifications: Bachelor's degree in computer science or software engineering Several years of professional programming experience Proficiency in the general technology of the World Wide Web: Hypertext Transfer Protocol (HTTP) Hypertext Markup Language (HTML) JavaScript Cascading Style Sheets (CSS) Proficiency in the following principles, practices, and techniques: Accessibility Interoperability Usability Security (especially prevention of SQL injection and cross-site scripting (XSS) attacks) Object-oriented programming (e.g. encapsulation, inheritance, modularity, polymorphism, etc.) Relational database design (e.g. normalization, orthogonality) Search engine optimization (SEO) Asynchronous JavaScript and XML (AJAX) Proficiency in the following specific technologies utilized by Company: C# or Visual Basic .NET ADO.NET (including ADO.NET Entity Framework) ASP.NET (including ASP.NET MVC Framework) Windows Presentation Foundation (WPF) Language Integrated Query (LINQ) Extensible Application Markup Language (XAML) jQuery Transact-SQL (T-SQL) Microsoft Visual Studio Microsoft Internet Information Services (IIS) Microsoft SQL Server Adobe Photoshop

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  • How to manipulate *huge* amounts of data

    - by Alejandro
    Hi there! I'm having the following problem. I need to store huge amounts of information (~32 GB) and be able to manipulate it as fast as possible. I'm wondering what's the best way to do it (combinations of programming language + OS + whatever you think its important). The structure of the information I'm using is a 4D array (NxNxNxN) of double-precission floats (8 bytes). Right now my solution is to slice the 4D array into 2D arrays and store them in separate files in the HDD of my computer. This is really slow and the manipulation of the data is unbearable, so this is no solution at all! I'm thinking on moving into a Supercomputing facility in my country and store all the information in the RAM, but I'm not sure how to implement an application to take advantage of it (I'm not a professional programmer, so any book/reference will help me a lot). An alternative solution I'm thinking on is to buy a dedicated server with lots of RAM, but I don't know for sure if that will solve the problem. So right now my ignorance doesn't let me choose the best way to proceed. What would you do if you were in this situation? I'm open to any idea. Thanks in advance!

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  • How to know if a device can be disabled or not?

    - by user326498
    I use the following code to enable/disable a device installed on my computer: SP_PROPCHANGE_PARAMS params; memset(&params, 0, sizeof(params)); devParams.cbSize = sizeof(devParams); params.ClassInstallHeader.cbSize = sizeof(params.ClassInstallHeader); params.ClassInstallHeader.InstallFunction = DIF_PROPERTYCHANGE; params.Scope = DICS_FLAG_GLOBAL; params.StateChange = DICS_DISABLE ; params.HwProfile = 0; // current profile if(!SetupDiSetClassInstallParams(m_hDev, &m_hDevInfo,&params.ClassInstallHeader,sizeof(SP_PROPCHANGE_PARAMS))) { dwErr = GetLastError(); return FALSE; } if(!SetupDiCallClassInstaller(DIF_PROPERTYCHANGE,m_hDev,&m_hDevInfo)) { dwErr = GetLastError(); return FALSE; } return TRUE; This code works perfectly only for those devices that can also be disabled by using Windows Device Manager, and won't work for some un-disabled devices such as my cpu device: Intel(R) Pentium(R) Dual CPU E2160 @ 1.80GHz. So the problem is how to determine if a device can be disabled or not programmatically? Is there any API to realize this goal? Thank you!

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  • Ultra-Portable Laptop or Tablet PC for Development and Sketching

    - by Nelson LaQuet
    I am a software developer that primarily writes in PHP, [X]HTML, CSS, Javascript, C# and C++. I use Eclipse for web development, Visual Studio 2008 for C++ and C# work, TortoiseSVN, Subversion server for local repositories, SQL Server Express, Apache and MYSQL. I also use Office 2007 for word processing and spreadsheets and use Vista Ultimate 64 as my primary operating system. The only other things I do on my laptop are watch movies, surf the internet and listen to music. I currently have a Acer Aspire 5100 (1.4 GHz AMD Turion X2, 2 GB of RAM and a 15.4" screen). This thing does not cut it in performance or portability, and in addition, my DVD drive failed. And before anybody posts about vista: I have had XP Professional 32 on it for the last two years, and recently upgraded to Vista 64. It is actually faster (with areo disabled) then XP; so it is not the OS that is causing the laptop to be slow. I usually sketch a lot, for explaining things, developing user interfaces and software architecture. Because of my requirements, I was thinking about a Lenovo X61 Tablet PC. It outperforms my current laptop, is significantly more portable, and... is a tablet. My question is: do any other software developers use this (or other tablets) for programming? Does it help to be able to sketch on the computer itself? And is it capable of being a good development machine? Will it handle the above software listed? If not, what is the best ultra-portable laptop that is good for programming? Or are ultra-portable laptops even good for programming? I could manage with my 15.4" screen, but am spoiled by my two 19" at my home desktop and my job's workstation.

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  • How to implement Horner's scheme for multivariate polynomials?

    - by gsreynolds
    Background I need to solve polynomials in multiple variables using Horner's scheme in Fortran90/95. The main reason for doing this is the increased efficiency and accuracy that occurs when using Horner's scheme to evaluate polynomials. I currently have an implementation of Horner's scheme for univariate/single variable polynomials. However, developing a function to evaluate multivariate polynomials using Horner's scheme is proving to be beyond me. An example bivariate polynomial would be: 12x^2y^2+8x^2y+6xy^2+4xy+2x+2y which would factorised to x(x(y(12y+8))+y(6y+4)+2)+2y and then evaluated for particular values of x & y. Research I've done my research and found a number of papers such as: staff.ustc.edu.cn/~xinmao/ISSAC05/pages/bulletins/articles/147/hornercorrected.pdf citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.40.8637&rep=rep1&type=pdf www.is.titech.ac.jp/~kojima/articles/B-433.pdf Problem However, I'm not a mathematician or computer scientist, so I'm having trouble with the mathematics used to convey the algorithms and ideas. As far as I can tell the basic strategy is to turn a multivariate polynomial into separate univariate polynomials and compute it that way. Can anyone help me? If anyone could help me turn the algorithms into pseudo-code that I can implement into Fortran myself, I would be very grateful.

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  • How to restrict a content of string to less than 4MB and save that string in DB using C#

    - by Pranay B
    I'm working on a project where I need to get the Text data from pdf files and dump the whole text in a DB column. With the help of iTextsharp, I got the data and referred it String. But now I need to check whether the string exceeds the 4MB limit or not and if it is exceeding then accept the string data which is less than 4MB in size. This is my code: internal string ReadPdfFiles() { // variable to store file path string filePath = null; // open dialog box to select file OpenFileDialog file = new OpenFileDialog(); // dilog box title name file.Title = "Select Pdf File"; //files to be accepted by the user. file.Filter = "Pdf file (*.pdf)|*.pdf|All files (*.*)|*.*"; // set initial directory of computer system file.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Desktop); // set restore directory file.RestoreDirectory = true; // execute if block when dialog result box click ok button if (file.ShowDialog() == DialogResult.OK) { // store selected file path filePath = file.FileName.ToString(); } //file path /// use a string array and pass all the pdf for searching //String filePath = @"D:\Pranay\Documentation\Working on SSAS.pdf"; try { //creating an instance of PdfReader class using (PdfReader reader = new PdfReader(filePath)) { //creating an instance of StringBuilder class StringBuilder text = new StringBuilder(); //use loop to specify how many pages to read. //I started from 5th page as Piyush told for (int i = 5; i <= reader.NumberOfPages; i++) { //Read the pdf text.Append(PdfTextExtractor.GetTextFromPage(reader, i)); }//end of for(i) int k = 4096000; //Test whether the string exceeds the 4MB if (text.Length < k) { //return the string text1 = text.ToString(); } //end of if } //end of using } //end try catch (Exception ex) { MessageBox.Show(ex.Message, "Please Do select a pdf file!!", MessageBoxButtons.OK, MessageBoxIcon.Warning); } //end of catch return text1; } //end of ReadPdfFiles() method Do help me!

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  • Cannot write to SD card -- canWrite is returning false

    - by Fizz
    Sorry for the ambiguous title but I'm doing the following to write a simple string to a file: try { File root = Environment.getExternalStorageDirectory(); if (root.canWrite()){ System.out.println("Can write."); File def_file = new File(root, "default.txt"); FileWriter fw = new FileWriter(def_file); BufferedWriter out = new BufferedWriter(fw); String defbuf = "default"; out.write(defbuf); out.flush(); out.close(); } else System.out.println("Can't write."); }catch (IOException e) { e.printStackTrace(); } But root.canWrite() seems to be returning false everytime. I am not running this off of an emulator, I have my android Eris plugged into my computer via USB and running the app off of my phone via Eclipse. Is there a way of giving my app permission so this doesn't happen? Also, this code seems to be create the file default.txt but what if it already exists, will it ignore the creation and just open it to write or do I have to catch something like FileAlreadyExists(if such an exception exists) which then just opens it and writes? Thanks for any help guys.

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  • Read file:// URLs in IE XMLHttpRequest

    - by Dan Fabulich
    I'm developing a JavaScript application that's meant to be run either from a web server (over http) or from the file system (on a file:// URL). As part of this code, I need to use XMLHttpRequest to load files in the same directory as the page and in subdirectories of the page. This code works fine ("PASS") when executed on a web server, but doesn't work ("FAIL") in Internet Explorer 8 when run off the file system: <html><head> <script> window.onload = function() { var xhr = new XMLHttpRequest(); xhr.open("GET", window.location.href, false); xhr.send(null); if (/TestString/.test(xhr.responseText)) { document.body.innerHTML="<p>PASS</p>"; } } </script> <body><p>FAIL</p></body> Of course, at first it fails because no scripts can run at all on the file system; the user is prompted a yellow bar, warning that "To help protect your security, Internet Explorer has restricted this webpage from running scripts or ActiveX controls that could access your computer." But even once I click on the bar and "Allow Blocked Content" the page still fails; I get an "Access is Denied" error on the xhr.open call. This puzzles me, because MSDN says that "For development purposes, the file:// protocol is allowed from the Local Machine zone." This local file should be part of the Local Machine Zone, right? How can I get code like this to work? I'm fine with prompting the user with security warnings; I'm not OK with forcing them to turn off security in the control panel. EDIT: I am not, in fact, loading an XML document in my case; I'm loading a plain text file (.txt).

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  • Why ntp settle time toe long?

    - by fercis
    I simply try to set-up NTP to my system. Both server and clients will run on my computer which are linked together with local link. One of them will have the reference clock. Both the server and Client are linux Ubuntu. I install ntp daemon to both sides. In clients, I enter the ip address of the server to /etc/ntp.conf. Everything works fine. However, the setting of the time to correct time in client side takes too long time (around 17 minutes). Is it possible to gather correct time just at startup. I write some code that regularly calls "ntpdate " by system call and the problem is solved but there has to be something that allows me to decrease the poll time of the client to 1-2 minutes. There are some settings as maxpoll - minpoll in ntp.conf, but I couldn't manage to understand their function, because with the best configuration (minpoll 4? 16 seconds?) I also cannot see that client side corrects its time before 10 minutes. In addition, in some cases my client is an embedded system (ARM - IGEP board) and it always opens with an irrelevant date (2-3 years ago). So the time that takes to correct the time should not depend on the time difference also.

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