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• What ORM for .NET should I use?

  - by eKek0

  I'm relatively new to .NET and have being using Linq2Sql for a almost a year, but it lacks some of the features I'm looking for now. I'm going to start a new project in which I want to use an ORM with the following characteristics: It has to be very productive, I don't want to be dealing with the access layer to save or retrieve objects from or to the database, but it should allows me to easily tweak any object before actually commit it to the database; also it should allows me to work easily with a changing database schema It should allows me to extend the objects mapped from the database, for example to add virtual attributes to them (virtual columns to a table) It has to be (at least almost) database agnostic, it should allows me to work with different databases in a transparent way It has to have not so much configuration or must be based on conventions to make it work It should allows me to work with Linq So, do you know any ORM that I could use? Thank you for your help. EDIT I know that an option is to use NHibernate. This appears as the facto standard for enterprise level applications, but also it seems that is not very productive because its deep learning curve. In other way, I have read in some other post here in SO that it doesn't integrate well with Linq. Is all of that true?

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• Parse Facebook API data using loop for getting fan page ID#s?

  - by Brandon Lee

  I've been learning how to parse json data returned from the facebook-api. I've figured out how to fetch fan pages from a specific profile id and want to parse them using a loop! Heres the code and example I have below: This is the data I get back from the facebook-api Array ( [0] => Array ( [page_id] => XXXXXX60828 ) [1] => Array ( [page_id] => XXXXXX0750 ) [2] => Array ( [page_id] => XXXXXX91225 ) [3] => Array ( [page_id] => XXXXXX1960343 ) [4] => Array ( [page_id] => XXXXXX60863 ) [5] => Array ( [page_id] => XXXXXX8582 ) ) I need to be able to put this data in a loop and extract the page_id#s out... still getting familiar with json and am having issues figuring this out? How can I get this in a loop using for each and strip out the page id#s?

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• slot function not getting called

  - by chappar

  I am learning QT and trying out some examples. I am trying to make a dialog that disappears a label when a button is pressed and makes it appear when the same button is pressed again. Below is the code. #include <QApplication> #include <QPushButton> #include <QLabel> #include <QDialog> #include <QObject> #include <QHBoxLayout> int main(int argc, char ** argv) { QApplication app(argc, argv); QDialog *dialog = new QDialog; QPushButton *testButton = new QPushButton(QObject::tr("test")); QLabel * testLabel = new QLabel (QObject::tr("test")); QHBoxLayout * layout = new QHBoxLayout; layout->addWidget(testButton); layout->addWidget(testLabel); QObject::connect(testButton, SIGNAL(toggled(bool)), testLabel, SLOT(setVisible(bool))); dialog->setLayout(layout); dialog->show(); return app.exec(); } It is not working. Whenever i press the test button nothing happens. But if i change the signal slot connections as QObject::connect(testButton, SIGNAL(clicked(bool)), testLabel, SLOT(setVisible(bool))); it makes the label disappear. So, why it is not working with signal "toggled". What i am guessing is, it is not able to find that signal. Can you guys throw some light?

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• What's wrong with debugging in Eclipse on Android?

  - by Sebastian Dwornik

  I've obviously been spoiled by Visual Studio, because although I'm just learning Android and the Eclipse environment, debugging apps in Eclipse is becoming a serious detriment to further development. For example, Eclipse will compile this divide by zero just fine: public class Lesson2Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate (savedInstanceState); int i = 1 / 0; TextView tv = new TextView (this); tv.setText ("Hello, Android!"); setContentView (tv); } } And then, when it executes it under the debugger, I will get a full screen of useless debug info, non of which actually points me to the specific line containing the error. The stackTrace is null within the exception ('e') info tree, and it simply states a message stating 'ArithmeticException'. (that's nice, how about you point me in the direction of where you found it!?) I've looked all over the screen and am baffled that this IDE can't get this right. Does developing with Eclipse resort everyone back to 1991 with printf() like logging at every interval then to track down bugs? Seriously. Is there a configuration or plug-in that I'm missing to help with this? I haven't tested this case with XCode, but if the iPhone dev. IDE handles this more like Visual Studio, then no wonder the Android marketplace has so few apps. I'm excited about Android, but it seems that Eclipse is getting in the way.

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• How do I apply a "template" or "skeleton" of code in C# here?

  - by Scott Stafford

  In my business layer, I need many, many methods that follow the pattern: public BusinessClass PropertyName { get { if (this.m_LocallyCachedValue == null) { if (this.Record == null) { this.m_LocallyCachedValue = new BusinessClass( this.Database, this.PropertyId); } else { this.m_LocallyCachedValue = new BusinessClass( this.Database, this.Record.ForeignKeyName); } } return this.m_LocallyCachedValue; } } I am still learning C#, and I'm trying to figure out the best way to write this pattern once and add methods to each business layer class that follow this pattern with the proper types and variable names substituted. BusinessClass is a typename that must be substituted, and PropertyName, PropertyId, ForeignKeyName, and m_LocallyCachedValue are all variables that should be substituted for. Are attributes usable here? Do I need reflection? How do I write the skeleton I provided in one place and then just write a line or two containing the substitution parameters and get the pattern to propagate itself? EDIT: Modified my misleading title -- I am hoping to find a solution that doesn't involve code generation or copy/paste techniques, and rather to be able to write the skeleton of the code once in a base class in some form and have it be "instantiated" into lots of subclasses as the accessor for various properties. EDIT: Here is my solution, as suggested but left unimplemented by the chosen answerer. // I'll write many of these... public BusinessClass PropertyName { get { return GetSingleRelation(ref this.m_LocallyCachedValue, this.PropertyId, "ForeignKeyName"); } } // That all call this. public TBusinessClass GetSingleRelation<TBusinessClass>( ref TBusinessClass cachedField, int fieldId, string contextFieldName) { if (cachedField == null) { if (this.Record == null) { ConstructorInfo ci = typeof(TBusinessClass).GetConstructor( new Type[] { this.Database.GetType(), typeof(int) }); cachedField = (TBusinessClass)ci.Invoke( new object[] { this.Database, fieldId }); } else { var obj = this.Record.GetType().GetProperty(objName).GetValue( this.Record, null); ConstructorInfo ci = typeof(TBusinessClass).GetConstructor( new Type[] { this.Database.GetType(), obj.GetType()}); cachedField = (TBusinessClass)ci.Invoke( new object[] { this.Database, obj }); } } return cachedField; }

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• Order in many to many relation in Django model

  - by Pietro Speroni

  I am writing a small website to store the papers I have written. The relation papers<- author is important, but the order of the name of the authors (which one is First Author, which one is second order, and so on) is also important. I am just learning Django so I don't know much. In any case so far I have done: from django.db import models class author(models.Model): Name = models.CharField(max_length=60) URLField = models.URLField(verify_exists=True, null=True, blank=True) def __unicode__(self): return self.Name class topic(models.Model): TopicName = models.CharField(max_length=60) def __unicode__(self): return self.TopicName class publication(models.Model): Title = models.CharField(max_length=100) Authors = models.ManyToManyField(author, null=True, blank=True) Content = models.TextField() Notes = models.TextField(blank=True) Abstract = models.TextField(blank=True) pub_date = models.DateField('date published') TimeInsertion = models.DateTimeField(auto_now=True) URLField = models.URLField(verify_exists=True,null=True, blank=True) Topic = models.ManyToManyField(topic, null=True, blank=True) def __unicode__(self): return self.Title This work fine in the sense that I now can define who the authors are. But I cannot order them. How should I do that? Of course I could add a series of relations: first author, second author,... but it would be ugly, and would not be flexible. Any better idea? Thanks

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• Recognize Dates In A String

  - by Tim Scott

  I want a class something like this: public interface IDateRecognizer { DateTime[] Recognize(string s); } The dates might exist anywhere in the string and might be any format. For now, I could limit to U.S. culture formats. The dates would not be delimited in any way. They might have arbitrary amounts of whitespace between parts of the date. The ideas I have are: ANTLR Regex Hand rolled I have never used ANTLR, so I would be learning from scratch. I wonder if there are libraries or code samples out there that do something similar that could jump start me. Is ANTLR too heavy for such a narrow use? I have used Regex a lot before, but I hate it for all the reasons that most people hate it. I could certainly hand roll it but I'd rather not re-solve a solved problem. Suggestions? UPDATE: Here is an example. Given this input: This is a date 11/3/63. Here is another one: November 03, 1963; and another one Nov 03, 63 and some more (11/03/1963). The dates could be in any U.S. format. They might have dashes like 11-2-1963 or weird extra whitespace inside like this: Nov   3,   1963, and even maybe the comma is missing like [Nov 3 63] but that's an edge case. The output should be an array of seven DateTimes. Each date would be the same: 11/03/1963 00:00:00.

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• Is there a way to prevent Maven Test from rebuilding the database?

  - by Christopher W. Allen-Poole

  I've recently been asked to, effectively, sell my department on unit testing. I can't tell you how excited this makes me, but I do have one concern. We're using JUnit with Spring and Maven, and this means that each time mvn test is called, it rebuilds the database. Obviously, we can't integrate that with our production server -- it would kill valuable data. How do I prevent the rebuilding without telling maven to skip testing? The best I could figure was to assign the script to operate in a test database (line breaks added for readability): mvn test -Ddbunit.schema=<database>test -Djdbc.url=jdbc:mysql://localhost/<database>test? createDatabaseIfNotExist=true&amp; useUnicode=true&amp;characterEncoding=utf-8 I can't help but think there must be a better way. I'm especially interested in learning if there is an easy way to tell Maven to only run tests on particular classes without building anything else? mvn -Dtest=<test-name> test still rebuilds the database. ======= update ======= Bit of egg on my face here. I didn't realize that I was using the same variable in two places, meaning that the POM was using a "skip.test" variable for both rebuilding the database and for running the tests...

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• Why is there a constructor method if you can assign the values to variables?

  - by Joel

  I'm just learning PHP, and I'm confused about what the purpose of the __construct() method? If I can do this: class Bear { // define properties public $name = 'Bill'; public $weight = 200; // define methods public function eat($units) { echo $this->name." is eating ".$units." units of food... <br />"; $this->weight += $units; } } Then why do it with a constructor instead? : class Bear { // define properties public $name; public $weight; public function __construct(){ $this->name = 'Bill'; $this->weight = 200; } // define methods public function eat($units) { echo $this->name." is eating ".$units." units of food... <br />"; $this->weight += $units; } }

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• How to Manage CSS Explosion

  - by Jason

  I have been heavily relying on CSS for a website that I am working on (currently, everything is done as property values within each tag on the website and I'm trying to get away from that to make updates significantly easier). The problem I am running into, is I'm starting to get a bit of "CSS explosion" going on. It is becoming difficult for me to decide how to best organize and abstract data within the CSS file. For example: I am using a large number of div tags within the website (previously it was completely tables based). So I'm starting to get a lot of CSS that looks like this... div.title { background-color: Blue; color: White; text-align: center; } div.footer { /* Stuff Here */ } div.body { /* Stuff Here */ } etc. It's not too bad yet, but since I am learning here, I was wondering if recommendations could be made on how best to organize the various parts of a CSS file. What I don't want to get to is where I have a separate CSS attribute for every single thing on my website (which I have seen happen), and I always want the CSS file to be fairly intuitive. (P.S. I do realize this is a very generic, high-level question. My ultimate goal is to make it easy to use the CSS files and demonstrate their power to increase the speed of web development so other individuals that may work on this site in the future will also get into the practice of using them rather than hard-coding values everywhere.)

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• Trouble compiling C/C++ project in NetBeans 6.8 with MinGW on Windows

  - by dontoo

  I am learning C and because VC++ 2008 doesn't support C99 features I have just installed NetBeans and configure it to work with MinGW. I can compile single file project ( main.c) and use debugger but when I add new file to project I get error "undefined reference to ... function(code) in that file..". Obviously MinGW does't link my files or I don't know how properly add them to my project (c standard library files work fine). /bin/make -f nbproject/Makefile-Debug.mk SUBPROJECTS= .build-conf make[1]: Entering directory `/c/Users/don/Documents/NetBeansProjects/CppApplication_7' /bin/make -f nbproject/Makefile-Debug.mk dist/Debug/MinGW-Windows/cppapplication_7.exe make[2]: Entering directory `/c/Users/don/Documents/NetBeansProjects/CppApplication_7' mkdir -p dist/Debug/MinGW-Windows gcc.exe -o dist/Debug/MinGW-Windows/cppapplication_7 build/Debug/MinGW-Windows/main.o build/Debug/MinGW-Windows/main.o: In function `main': C:/Users/don/Documents/NetBeansProjects/CppApplication_7/main.c:5: undefined reference to `X' collect2: ld returned 1 exit status make[2]: *** [dist/Debug/MinGW-Windows/cppapplication_7.exe] Error 1 make[2]: Leaving directory `/c/Users/don/Documents/NetBeansProjects/CppApplication_7' make[1]: *** [.build-conf] Error 2 make[1]: Leaving directory `/c/Users/don/Documents/NetBeansProjects/CppApplication_7' make: *** [.build-impl] Error 2 BUILD FAILED (exit value 2, total time: 1s) main.c #include "header.h" int main(int argc, char** argv) { X(); return (EXIT_SUCCESS); } header.h #ifndef _HEADER_H #define _HEADER_H #include <stdio.h> #include <stdlib.h> void X(void); #endif source.c #include "header.h" void X(void) { printf("dsfdas"); }

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• List<object>.RemoveAll - How to create an appropriate Predicate

  - by CJM

  This is a bit of noob question - I'm still fairly new to C# and generics and completely new to predicates, delegates and lamda expressions... I have a class 'Enquiries' which contains a generic list of another class called 'Vehicles'. I'm building up the code to add/edit/delete Vehicles from the parent Enquiry. And at the moment, I'm specifically looking at deletions. From what I've read so far, it appears that I can use Vehicles.RemoveAll() to delete an item with a particular VehicleID or all items with a particular EnquiryID. My problem is understanding how to feed .RemoveAll the right predicate - the examples I have seen are too simplistic (or perhaps I am too simplistic given my lack of knowledge of predicates, delegates and lambda expressions). So if I had a List<Of Vehicle> Vehicles where each Vehicle had an EnquiryID, how would I use Vehicles.RemoveAll() to remove all vehicles for a given EnquiryID? I understand there are several approaches to this so I'd be keen to hear the differences between approaches - as much as I need to get something working, this is also a learning exercise. As an supplementary question, is a Generic list the best repository for these objects? My first inclination was towards a Collection, but it appears I am out of date. Certainly Generics seem to be preferred, but I'm curious as to other alternatives. Thanks

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• positioning text/image with a border

  - by user167487

  Learning html/css, having trouble with positioning text and or images within a border on a page exactly where i want them. I'm first trying to stack them underneath each other vertically, but i dont know how to move each box underneath, at the moment they are stacking horizontally until they go over the max width, what do i do? HTML: <div id="column1"> <p>blah blah blah</p> </div> <div id="column2"> <p>blah blah blah</p> </div> <div id="column3"> <p>blah blah blah</p> </div> CSS: p { font-family: Tahoma; font-size: 14px; margin: 1px; padding: 10px; text-align: left; background-color: white; width: 800px; } #column1 {float: left; position: relative; width: 200px; padding: 3px; background: gray ; top: 10px;margin: 1px; } #column2 {float: left; position: relative; width: 200px; padding: 3px; background: orange; top:50px;margin: 1px; } #column3 {float: left; position: relative; width: 200px; padding: 3px; background: gray; top: 100px;margin: 1px; }

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• Can't get this SPARQL query to work

  - by Jason

  Okay, I'm just learning to use SPARQL to query data from dbpedia.org and I'm using dbpedia's http://dbpedia.org/snorql/ to run my queries in. I am trying to get a list of MusicalArtists based on searching for the same string over three fields like so: SELECT ?subject ?artistRdfsLabel ?artistFoafName ?artistDbpedia2Name WHERE { ?subject rdf:type <http://dbpedia.org/ontology/MusicalArtist> . OPTIONAL { ?subject rdfs:label ?artistRdfsLabel . } OPTIONAL { ?subject foaf:name ?artistFoafName . } OPTIONAL { ?subject dbpedia2:name ?artistDbpedia2Name . } FILTER ( str(?artistRdfsLabel) = "Stevie Nicks" || str(?artistFoafName) = "Stevie Nicks" || str(?artistDbpedia2Name) = "Stevie Nicks" ) } LIMIT 10 This works because "Stevie Nicks" has all three fields (rdfs:label, foaf:name, dbpedia2:name). But when I try to query by another MusicalArtist that doesn't have all three ("Depeche Mode" for example) I get no results. I have tried various things like BIND(COALESCE(?field,...,...) AS ?artistName) to filter by ?artistName and I also tried UNION but nothing seems to work. Can someone point out the error of my SPARQL ways? :) Thanks! Jason

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• Applying for .net jobs as a "self learner"

  - by DeanMc

  Hi All, I have recently started applying for .Net jobs. I currently work in a sales role with a large telco. I found out quite late that I like programming and as such bought my house and made commitments that mean college is not an option. What I would like to know is, is it harder to get a junior job as a self learner? I have gotten a few enquiries regarding my C.V but nothing concrete yet. I try to be involved in projects as I get the chance and tend to put up any worthwhile projects as I develop them. Some examples of my work are: A Xaml lexer and parser: http://www.xlight.mendhak.com A font obfuscation tool: http://www.silverlightforums.com/showthread.php?1516-Font-Obsfucation-Tool-ALPHA A tagger for m4a: http://projectaudiophile.codeplex.com/SourceControl/list/changesets I, of course think that these are great examples of my work but that is my opinion based on self learning. The other query is how much should I actually know? I've never used linked lists but I know that strings are immutable and I understand what that means. I am only touching on T-SQL but I understand things like how properties function in IL (as two standard methods :) ). I suppose I understand a lot of concepts but specific features need some looking up to implement as I may not know the syntax off the top of my head.

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• Class Plugins in PHP?

  - by YuriKolovsky

  i just got some more questions while learning PHP, does php implement any built in plugin system? so the plugin would be able to change the behavior of the core component. for example something like this works: include 'core.class.php'; include 'plugin1.class.php'; include 'plugin2.class.php'; new plugin2; where core.class.php contains class core { public function coremethod1(){ echo 'coremethod1'; } public function coremethod2(){ echo 'coremethod2'; } } plugin1.class.php contains class plugin1 extends core { public function coremethod1(){ echo 'plugin1method1'; } } plugin2.class.php contains class plugin2 extends plugin1 { public function coremethod2(){ echo 'plugin2method2'; } } This would be ideal, if not for the problem that now the plugins are dependable on each other, and removing one of the plugins: include 'core.class.php'; //include 'plugin1.class.php'; include 'plugin2.class.php'; new plugin2; breaks the whole thing... are there any proper methods to doing this? if there are not, them i might consider moving to a different langauge that supports this... thanks for any help.

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• Properties vs. Fields: Need help grasping the uses of Properties over Fields.

  - by pghtech

  First off, I have read through a list of postings on this topic and I don't feel I have grasped properties because of what I had come to understand about encapsulation and field modifiers (private, public..ect). One of the main aspects of C# that I have come to learn is the importance of data protection within your code by the use of encapsulation. I 'thought' I understood that to be because of the ability of the use of the modifiers (private, public, internal, protected). However, after learning about properties I am sort of torn in understanding not only properties uses, but the overall importance/ability of data protection (what I understood as encapsulation) within C#. To be more specific, everything I have read when I got to properties in C# is that you should try to use them in place of fields when you can because of: 1) they allow you to change the data type when you can't when directly accessing the field directly. 2) they add a level of protection to data access However, from what I 'thought' I had come to know about the use of field modifiers did #2, it seemed to me that properties just generated additional code unless you had some reason to change the type (#1) - because you are (more or less) creating hidden methods to access fields as opposed to directly. Then there is the whole modifiers being able to be added to Properties which further complicates my understanding for the need of properties to access data. I have read a number of chapters from different writers on "properties" and none have really explained a good understanding of properties vs. fields vs. encapsulation (and good programming methods). Can someone explain: 1) why I would want to use properties instead of fields (especially when it appears I am just adding additional code 2) any tips on recognizing the use of properties and not seeing them as simply methods (with the exception of the get;set being apparent) when tracing other peoples code? 3) Any general rules of thumb when it comes to good programming methods in relation to when to use what? Thanks and sorry for the long post - I didn't want to just ask a question that has been asked 100x without explaining why I am asking it again.

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• How do I define a Calculated Measure in MDX based on a Dimension Attribute?

  - by ShaneD

  I would like to create a calculated measure that sums up only a specific subset of records in my fact table based on a dimension attribute. Given: Dimension Date LedgerLineItem {Charge, Payment, Write-Off, Copay, Credit} Measures LedgerAmount Relationships * LedgerLineItem is a degenerate dimension of FactLedger If I break down LedgerAmount by LedgerLineItem.Type I can easily see how much is charged, paid, credit, etc, but when I do not break it down by LedgerLineItem.Type I cannot easily add the credit, paid, credit, etc into a pivot table. I would like to create separate calculated measures that sum only specific type (or multiple types) of ledger facts. An example of the desired output would be: | Year | Charged | Total Paid | Amount - Ledger | | 2008 | $1000 | $600 | -$400 | | 2009 | $2000 | $1500 | -$500 | | Total | $3000 | $2100 | -$900 | I have tried to create the calculated measure a couple of ways and each one works in some circumstances but not in others. Now before anyone says do this in ETL, I have already done it in ETL and it works just fine. What I am trying to do as part of learning to understand MDX better is to figure out how to duplicate what I have done in the ETL in MDX as so far I am unable to do that. Here are two attempts I have made and the problems with them. This works only when ledger type is in the pivot table. It returns the correct amount of the ledger entries (although in this case it is identical to [amount - ledger] but when I try to remove type and just get the sum of all ledger entries it returns unknown. CASE WHEN ([Ledger].[Type].currentMember = [Ledger].[Type].&[Credit]) OR ([Ledger].[Type].currentMember = [Ledger].[Type].&[Paid]) OR ([Ledger].[Type].currentMember = [Ledger].[Type].&[Held Money: Copay]) THEN [Measures].[Amount - ledger] ELSE 0 END This works only when ledger type is not in the pivot table. It always returns the total payment amount, which is incorrect when I am slicing by type as I would only expect to see the credit portion under credit, the paid portion, under paid, $0 under charge, etc. sum({([Ledger].[Type].&[Credit]), ([Ledger].[Type].&[Paid]), ([Ledger].[Type].&[Held Money: Copay])}, [Measures].[Amount - ledger]) Is there any way to make this return the correct numbers regardless of whether Ledger.Type is included in my pivot table or not?

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• Getting Started with Ruby & Ruby on Rails

  - by JakeTheSnake

  Some background: I'm a jack-of-all traits, one of which is programming. I learned VB6 through Excel and PHP for creating websites and so far it's worked out just fine for me. I'm not CS major or even mathematically inclined - logic is what interests me. Current status: I'm willing to learn new and more powerful languages; my first foray into such a route is learning Ruby. I went to the main Ruby website and did the interactive intro. (by the way, I'm currently getting redirected to google.com when I try the link...it's happening to other websites as well...is my computer infected?) I liked what I learned and wanted to get started using Ruby to create websites. I downloaded InstantRails and installed it; everything so far has been fine - the program starts up just fine, and I can test some Ruby code in the console. However my troubles begin when I try and view a web page with Ruby code present. Lastly, my problem: As in PHP, I can browse to the .php file directly and through using PHP tags and some simple 'echo' statements I can be on my way in making dynamic web pages. However with the InstantRails app working, accessing a .rb or .rhtml page doesn't produce similar results. I made a simple text file named 'test.rb' and put basic HTML tags in there (html, head, body) and the Ruby tags <%= and % with some ruby code inside. The web page actually shows the tags and the code - as if it's all just plain HTML. I take it Ruby isn't parsing the page before it is displayed to the user, but this is where my lack of understanding of the Ruby environment stops me short. Where do I go from here?

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• What does O(log n) mean exactly?

  - by Andreas Grech

  I am currently learning about Big O Notation running times and amortized times. I understand the notion of O(n) linear time, meaning that the size of the input affects the growth of the algorithm proportionally...and the same goes for, for example, quadratic time O(n2) etc..even algorithms, such as permutation generators, with O(n!) times, that grow by factorials. For example, the following function is O(n) because the algorithm grows in proportion to its input n: f(int n) { int i; for (i = 0; i < n; ++i) printf("%d", i); } Similarly, if there was a nested loop, the time would be O(n2). But what exactly is O(log n)? For example, what does it mean to say that the height of a complete binary tree is O(log n)? I do know (maybe not in great detail) what Logarithm is, in the sense that: log10 100 = 2, but I cannot understand how to identify a function with a logarithmic time.

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• Help understanding linux/tcp.h

  - by Chris

  I'm learning to use raw sockets, and im trying to prase out the tcp header data, but i can't seem to figure out what res1, ece, and cwr are. Through my networking book and google i know what the rest stand for, but can't seem to find anything on those three. Below is the tcphdr struct in my includes area. Ive commented the parts a bit as i was figureing out what they stood for. struct tcphdr { __be16 source; __be16 dest; __be32 seq; __be32 ack_seq; #if defined(__LITTLE_ENDIAN_BITFIELD) _u16 res1:4, doff:4,//tcp header length fin:1,//final syn:1,//synchronization rst:1,//reset psh:1,//push ack:1,//ack urg:1,// urge ece:1, cwr:1; #elif defined(_BIG_ENDIAN_BITFIELD) __u16 doff:4,//tcp header length res1:4, cwr:1, ece:1, urg:1,//urge ack:1,//ack psh:1,//push rst:1,//reset syn:1,//synchronization fin:1;//final #else #error "Adjust your defines" #endif __be16 window; __sum16 check; __be16 urg_ptr; };

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• Help me understand dynamic layouts in Sinatra

  - by thermans

  Help me understand this; I'm learning Sinatra (and Rails for that matter, er, and Ruby). Say I'm doing a search app. The search form is laid out in one div, and the results will be laid out in another. The search form is rendered into the div by a previous view (maybe from a login form). I want to process the form params, perform the search, and render the results into the results div. If I have a single "yield" in the layout and render the divs from different views, the results div erases the search div when it renders. If I define the divs in the default layout, then just render the content, obviously the layout will be messed up: there would have to be two "yields" and I don't think Sinatra supports passing blocks in to yields. I tried foca's sinatra-content-for plugin, and that seems closer to what I need. But I can't figure out where to place the "yield_content" statements. If I have this haml in my layout: #search -# search form = yield_content :search #results -# search results = yield_content :results ... this in my search view: - content_for :search do %form{:method => "post"... etc. ... and this in the results view: - content_for :results do %table{:class => 'results'... etc. This sort of works but when I render the results view, the search div is emptied out. I would like to have it remain. Am I doing something wrong? How should I set this up?

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• can I disable the "(Type e to repeat macro)" message in emacs?

  - by lindes

  Hi there, So, I've finally made the plunge, and have gotten to the state where I'm quite happy to have switched from vi and vim to emacs... I've been putting stuff in my .emacs file, learning how to evaluate things (not to mention becoming familiar with movement commands), etc. etc. etc. And now I have a problem with a require line in my .emacs file (a require statement*), which bombs out when I launch emacs (and generally fails to work). So, this lead me to the following situation: In the process of trying to debug the above situation, one of the steps I did was to open the file I was trying to require, and evaluate it bit by bit, using C-M-f and C-x C-e (and later just M-x eval-buffer), which all worked fine. But along the way of the section-by-section, I got tired of typing all those, and so I recorded a keyboard macro... C-x ( C-M-f C-x C-e C-x ) and then C-x e... which gave me a message in the minibuffer (I think I'm using the right name), saying (Type e to repeat macro). Which meant I could no longer see the resultant value of the evaluation of each section of code... which, while not critical in this case, I was liking having. Which leads me to the actual question: Is there a way to disable that message, and/or to cause the minibuffer to show multiple lines at once? I know about the *Messages* buffer, and that could have helped, I'm just wondering if there's a way to either disable that message, or otherwise make it coexist with other messages. Any suggestions? Thanks! lindes * - the problem at hand, which is not really my question, is that (require 'ruby-mode/ruby-mode) fails, even though emacs is definitely and successfully (per system call tracing) opening and reading the ruby-mode.el file. I presume this is because the provide line says just 'ruby-mode. I've found a solution for this, but if anyone can point me to any "best practices", I'd appreciate it.

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• Any high-level languages that can use c libraries?

  - by Isaiah

  I know this question could be in vain, but it's just out of curiosity, and I'm still much a newb^^ Anyways I've been loving python for some time while learning it. My problem is obviously speed issues. I'd like to get into indie game creation, and for the short future, 2d and pygame will work. But I'd eventually like to branch into the 3d area, and python is really too slow to make anything 3d and professional. So I'm wondering if there has ever been work to create a high-level language able to import and use c libraries? I've looked at Genie and it seems to be able to use certain libraries, but I'm not sure to what extent. Will I be able to use it for openGL programing, or in a c game engine? I do know some lisp and enjoy it a lot, but there aren't a great many libraries out there for it. Which leads to the problem: I can't stand C syntax, but C has libraries galore that I could need! And game engines like irrlicht. Is there any language that can be used in place of C around C? Thanks so much guys

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• Beyond core java

  - by Paul

  Coming to the end of the first year of my CS degree, we've done some Java but just the core stuff; manipulating strings and arrays, inheritance, implementing logic etc. I visit this website daily and I see so much stuff that is beyond me; using frameworks; managing databases etc. It makes me feel like I've just learned the syntax of Java, and there is so much more to do with it. My question is though, how do I get there? I don't think I'm advanced enough to join an open source project, which seems to be suggested often (though I'd love to) and I've looked at other similar questions on here (like this one) but even then I don't think that'd work for me.. firstly, could somebody try give me some commonly used frameworks etc and how and what they are used for? Where would be a good place to start? How did you get started in using the things you do? Or perhaps you think I'm going down the wrong route. Should I learn another language, and just wait until the moment occurs where it's clear what I should be doing? I'm only in the first year of my degree, so far we've lightly covered Haskell and Java, and I've done a little HTML and CSS in my free time. I know that next year we cover python, so perhaps I should just wait till then and see if I prefer that? I feel like I also risk learning something in depth and then never using it... I suppose I'm also asking for personal experiences; was there a point where you felt you'd exceeded the basic grasp of a language (does not necessarily have to be Java related) and reach a more "advanced" level? I guess I'll put subjective tag on this, but really I just want to know how to get beyond the basic understanding of a language.

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