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  • Javascript OOP - accessing the inherited property or function from a closure within a subclass

    - by Ali
    Hi All, I am using the javascript inheritance helper provided here: http://ejohn.org/blog/simple-javascript-inheritance/ I have the following code, and I have problem accessing the inherited property or function from a closure within a subclass as illustrated below. I am new to OOP javascript code and I appreciate your advice. I suppose within the closure, the context changes to JQuery (this variable) hence the problem. I appreciate your comments. Thanks, -A PS - Using JQuery 1.5 var Users = Class.extend({ init: function(names){this.names = names;} }); var HomeUsers = Users.extend({ work:function(){ // alert(this.names.length); // PRINTS A // var names = this.names; // If I make a local alias it works $.map([1,2,3],function(){ var newName = this.names.length; //error this.names is not defined. alert(newName); }); } }); var users = new HomeUsers(["A"]); users.work();

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  • VB.NET Button Issue

    - by Michael
    I am having problem with a button the code of my button is. Private Sub btnCalculateCosts_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculateCosts.Click it handles: ' This Calculate Costs button click event handler edits the ' registration(costs) form to ensure it contains valid data. ' Then, after passing control to the business class, it ' displays the registration cost. Dim objCourse As Course Dim objCourseCostsFile As Course Dim InputError As Boolean = False ' Is student ID entered properly If Me.txtCorporateID.MaskFull = False Then MessageBox.Show("Enter your Corporate ID in the Corporate ID box", _ "Error") Me.txtCorporateID.Clear() Me.txtCorporateID.Focus() InputError = True ' Is student name entered properly ElseIf Me.txtFirstName.TextLength < 1 Or _ Me.txtFirstName.Text < "A" Then MessageBox.Show("Please enter your first name in the First Name box", "Error") Me.txtFirstName.Clear() Me.txtFirstName.Focus() InputError = True ' Is number of units entered properly ElseIf Me.txtLastName.TextLength < 1 Or _ Me.txtLastName.Text < "A" Then MessageBox.Show("Please enter your last name in the Last Name box", "Error") Me.txtLastName.Clear() Me.txtLastName.Focus() InputError = True ' Is number of units entered properly ElseIf Not IsNumeric(Me.txtNumberOfDays.Text) Then MessageBox.Show("Enter the units in the Number of Units box", _ "Error") Me.txtNumberOfDays.Clear() Me.txtNumberOfDays.Focus() InputError = True ' Has 1-4 units been entered ElseIf Convert.ToInt32(Me.txtNumberOfDays.Text) < 1 _ Or Convert.ToInt32(Me.txtNumberOfDays.Text) > 4 Then MessageBox.Show("Units must be 1 - 4", "Error") Me.txtNumberOfDays.Clear() Me.txtNumberOfDays.Focus() InputError = True End If ' If no input error, process the registration costs If Not InputError Then If Me.radPreConferenceCourse.Checked = False Then objCourse = New Course(txtCorporateID.Text, txtFirstName.Text, txtLastName.Text, txtNumberOfDays.Text) Me.lblCosts.Visible = True Me.lblCosts.Text = "Total Conference Costs Are: " _ & (objCourse.ComputeCosts()).ToString("C2") Else objCourse = New Course(txtCorporateID.Text, txtFirstName.Text, txtLastName.Text, txtNumberOfDays.Text, g) Me.lblCosts.Visible = True Me.lblCosts.Text = "Total Conference Costs Are: " _ & (objCourse.ComputeCosts()).ToString("C2") Receiving the error: Handles clause requrieres a WithEvents variable defined in the containing type or one of its base types.

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  • MS Access Form - Horizontal Anchor Affecting Data Update

    - by nicholas
    Running Access 2007 with a databound form. The form Record Source is set to a query, and all fields in the form have a defined Control Source; nothing fancy, just field names. The form is a Single form with record navigation buttons which perform a "Next Record" and "Previous Record" actions. As I navigate the records the controls in the header update correctly. However, if I change a control Horizontal Anchor property to "Right" the fields no longer update on record navigation. This is observed for both text box and combo box controls. I can switch the anchoring back to "Left" and the updating works as it should. Is there some reason anchoring would affect a control updating of in an Access form? Or is this a bug that has been observed before? The only workaround I can think of is to assign the control text/value property in the form OnCurrent event, but this seems somewhat sloppy. Am I missing something here?

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  • Creating a join based on data from other tables...

    - by Workshop Alex
    I'm dealing with a database structure that can be defined as "illogical". It has about 100 different schema's with all different table structures per schema. Only one common factor is a "Version" table in each schema containing about 4 fields. (Thus, there are about 100 Version tables in the database.) There's also another table (view, actually) containing a list of all the schema's in the database that have a version table. I need a stored procedure that walks through all the schema's and selects all data from the Version table, adding the schema name as a fifth field to the result. Basically, this stored procedure is to return a list of all version records per schema. My idea: first walk through the schema list to create one new SQL statements that will JOIN all the schema.version tables into one SQL statement. Then I return the result of that query. How to do this? Or does anyone have a better suggestion? (No, redesigning the structure is NOT an option.)

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  • managedObjectContext question...

    - by treasure
    Hello, I have an app which is a UITabBarController, I have defined two subviews Both tabs have their Class attribute in the Identity Inspector set to UINavigationController. Now i have managed to get this far with my coding after VERY LONG trials. - (void)viewDidLoad { [super viewDidLoad]; myAppDelegate *appDelegate = (myAppDelegate *)[[UIApplication sharedApplication] delegate]; self.managedObjectContext = appDelegate.managedObjectContext; { NSError *error = nil; NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; [fetchRequest setEntity:[NSEntityDescription entityForName:@"User" inManagedObjectContext:self.managedObjectContext]]; NSArray *fetchedItems = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error]; NSEntityDescription *entityDesc = [NSEntityDescription entityForName:@"User" inManagedObjectContext:self.managedObjectContext]; // replace the old data with new. this DOESNT WORK if (fetchedItems.count > 0) { Usr *newUsr; for (newUsr in fetchedItems) { if ([newUsr.name isEqualToString:@"Line One"]) { newUsr.uName = @"Line One (new)"; } } } //add a new default data. THIS ADDS DATA TO MY TABLEVIEW BUT IT DOESNT SAVE THEM TO THE SQLITE User *addedDefaultdata = nil; addedDefaultdata = [[User alloc] initWithEntity:entityDesc insertIntoManagedObjectContext:self.managedObjectContext]; addedDefaultdata.name = @"Added new 1"; [addedDefaultdata release]; } NSError *error = nil; if (![[self fetchedResultsController] performFetch:&error]) { NSLog(@"Unresolved error %@, %@", error, [error userInfo]); abort(); } } and my appdelegate looks like this: - (void)applicationDidFinishLaunching:(UIApplication *)application { [application setStatusBarStyle:UIStatusBarStyleBlackOpaque]; [window addSubview:navigationController.view]; [window makeKeyAndVisible]; } now I cannot quire the "User" at all! although i get no errors or warnings! Any suggestions would be much appreciated! Thanks

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  • how to delete a line from file using awk filtered by some string

    - by embedded
    I have a file delimited by space. I need to write an awk command that receives a host name argument and it should replace the host name if it already defined in the file. It must be a full match not partially - if the file contains this host name: localhost searching for "ho" will fail and it will be added to the end of the file. another option is a delete: again awk receives host name argument and it should remove it from the file if exists. This is what I have so far: (It needs some enhancements) if [ "$DELETE_FLAG" == "" ]; then # In this case the entry should be added or updated # if clause deals with updating an existing entry # END clause deals with adding a new entry awk -F"[ ]" "BEGIN { found = 0;} \ { \ if ($2 == $HOST_NAME) { \ print \"$IP_ADDRESS $HOST_NAME\"; \ found = 1; \ } else { \ print \$0; \ } \ } \ END { \ if (found == 0) { \ print \"$IP_ADDRESS $HOST_NAME\"; } \ } " \ /etc/hosts > /etc/temp_hosts else # Delete an existing entry awk -F'[ ]' '{if($2 != $HOST_NAME) { print $0} }' /etc/hosts > /etc/temp_hosts fi Thanks

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  • Weird Rails database errors

    - by Jason Swett
    I've had some trouble getting my Rails app to connect to PostgreSQL so I decided to just say screw it and use SQLite for now. (I'm using the tutorial here: http://guides.rubyonrails.org/getting_started.html) I started a BRAND NEW, fresh Rails app from this tutorial. When I visit my app in the browser after deleting public/index.html, I get this the first time: Please install the pg adapter: `gem install activerecord-pg-adapter` (no such file to load -- active_record/connection_adapters/pg_adapter) That's odd to me because I'm not mentioning PostgreSQL anywhere. Here's my databases.yml: # SQLite version 3.x # gem install sqlite3-ruby (not necessary on OS X Leopard) development: adapter: sqlite3 database: db/development.sqlite3 pool: 5 timeout: 5000 # Warning: The database defined as "test" will be erased and # re-generated from your development database when you run "rake". # Do not set this db to the same as development or production. test: adapter: sqlite3 database: db/test.sqlite3 pool: 5 timeout: 5000 production: adapter: sqlite3 database: db/production.sqlite3 pool: 5 timeout: 5000 To make things more confusing, I only get that "pg adapter" error on the first load. For every subsequent page request, I get this error: ActiveRecord::ConnectionNotEstablished So even though I removed all mention of PostgreSQL, I'm still getting errors. What could be going on?

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  • Ways to make (relatively) safe assumptions about the type of concrete subclasses?

    - by Kylotan
    I have an interface (defined as a abstract base class) that looks like this: class AbstractInterface { public: bool IsRelatedTo(const AbstractInterface& other) const = 0; } And I have an implementation of this (constructors etc omitted): class ConcreteThing { public: bool IsRelatedTo(const AbstractInterface& other) const { return m_ImplObject.has_relationship_to(other.m_ImplObject); } private: ImplementationObject m_ImplObject; } The AbstractInterface forms an interface in Project A, and the ConcreteThing lives in Project B as an implementation of that interface. This is so that code in Project A can access data from Project B without having a direct dependency on it - Project B just has to implement the correct interface. Obviously the line in the body of the IsRelatedTo function cannot compile - that instance of ConcreteThing has an m_ImplObject member, but it can't assume that all AbstractInterfaces do, including the other argument. In my system, I can actually assume that all implementations of AbstractInterface are instances of ConcreteThing (or subclasses thereof), but I'd prefer not to be casting the object to the concrete type in order to get at the private member, or encoding that assumption in a way that will crash without a diagnostic later if this assumption ceases to hold true. I cannot modify ImplementationObject, but I can modify AbstractInterface and ConcreteThing. I also cannot use the standard RTTI mechanism for checking a type prior to casting, or use dynamic_cast for a similar purpose. I have a feeling that I might be able to overload IsRelatedTo with a ConcreteThing argument, but I'm not sure how to call it via the base IsRelatedTo(AbstractInterface) method. It wouldn't get called automatically as it's not a strict reimplementation of that method. Is there a pattern for doing what I want here, allowing me to implement the IsRelatedTo function via ImplementationObject::has_relationship_to(ImplementationObject), without risky casts? (Also, I couldn't think of a good question title - please change it if you have a better one.)

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  • What does "Select Distinct Null As xxxxx" mean?

    - by Soylent Green
    Background: I am mapping Sybase stored procedure return values to java objects using Spring. For example I map a Sybase datatype of varchar as a String type in Java, and a Sybase datatype of int as an int type in Java, etc. I have come across the following code in one of the stored procedures: SELECT DISTINCT A.Col1 AS val1, A.Col2 AS val2, NULL AS someVal, A.col3 AS val3, ... A.col9 AS val9 FROM #SomeTable A ORDER BY Col2, Col3 I have 2 related questions: What does Null mean in this scenario? I am confused as to what is happening here. I am able to determine the data type of Col1, Col2, etc. of course by looking at the table definition of Table A defined earlier in the stored procedure. Thus I know what datatype I can define in my Java object for val1, val2, etc.. But what about "someVal"? What datatype mapping am I supposed to perform for this Null value? I am fairly inexperienced in SQL. Perhaps the answer is much simpler than I realize.

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  • Performance difference between functions and pattern matching in Mathematica

    - by Samsdram
    So Mathematica is different from other dialects of lisp because it blurs the lines between functions and macros. In Mathematica if a user wanted to write a mathematical function they would likely use pattern matching like f[x_]:= x*x instead of f=Function[{x},x*x] though both would return the same result when called with f[x]. My understanding is that the first approach is something equivalent to a lisp macro and in my experience is favored because of the more concise syntax. So I have two questions, is there a performance difference between executing functions versus the pattern matching/macro approach? Though part of me wouldn't be surprised if functions were actually transformed into some version of macros to allow features like Listable to be implemented. The reason I care about this question is because of the recent set of questions (1) (2) about trying to catch Mathematica errors in large programs. If most of the computations were defined in terms of Functions, it seems to me that keeping track of the order of evaluation and where the error originated would be easier than trying to catch the error after the input has been rewritten by the successive application of macros/patterns.

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  • Multiple Foreign keys to a single table and single key pointing to more than one table

    - by user1216775
    I need some suggestions from the database design experts here. I have around six foreign keys into a single table (defect) which all point to primary key in user table. It is like: defect (.....,assigned_to,created_by,updated_by,closed_by...) If I want to get information about the defect I can make six joins. Do we have any better way to do it? Another one is I have a states table which can store one of the user-defined set of values. I have defect table and task table and I want both of these tables to share the common state table (New, In Progress etc.). So I created: task (.....,state_id,type_id,.....) defect(.....,state_id,type_id,...) state(state_id,state_name,...) importance(imp_id,imp_name,...) There are many such common attributes along with state like importance(normal, urgent etc), priority etc. And for all of them I want to use same table. I am keeping one flag in each of the tables to differentiate task and defect. What is the best solution in such a case? If somebody is using this application in health domain, they would like to assign different types, states, importances for their defect or tasks. Moreover when a user selects any project I want to display all the types,states etc under configuration parameters section.

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  • Best loose way to get objects with common base class

    - by Michael Teper
    I struggled to come up with a good title for this question, so suggestions are welcome. Let's say we have an abstract base class ActionBase that looks something like this: public abstract class ActionBase { public abstract string Name { get; } public abstract string Description { get; } // rest of declaration follows } And we have a bunch of different actions defined, like a MoveFileAction, WriteToRegistryAction, etc. These actions get attached to Worker objects: public class Worker { private IList<ActionBase> _actions = new List<ActionBase>(); public IList<ActionBase> Actions { get { return _actions; } } // worker stuff ... } So far, pretty straight-forward. Now, I'd like to have a UI for setting up Workers, assigning Actions, setting properties, and so on. In this UI, I want to present a list of all available actions, along with their properties, and for that I'd want to first gather up all the names and descriptions of available actions (plus the type) into a collection of the following type of item: public class ActionDescriptor { public string Name { get; } public string Description { get; } poblic Type Type { get; } } Certainly, I can use reflection to do this, but is there a better way? Having Name and Description be instance properties of ActionBase (as opposed to statics on derived classes) smells a bit, but there isn't an abstract static in C#. Thank you!

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  • Difference dynami static 2d array c++

    - by snorlaks
    Hello, Im using opensource library called wxFreeChart to draw some XY charts. In example there is code which uses static array as a serie : double data1[][2] = { { 10, 20, }, { 13, 16, }, { 7, 30, }, { 15, 34, }, { 25, 4, }, }; dataset-AddSerie((double *) data1, WXSIZEOF(dynamicArray)); WXSIZEOF ismacro defined like: sizeof(array)/sizeof(array[0]) In this case everything works great but in my program Im using dynamic arrays (according to users input). I made a test and wrotecode like below: double **dynamicArray = NULL; dynamicArray = new double *[5] ; for( int i = 0 ; i < 5 ; i++ ) dynamicArray[i] = new double[2]; dynamicArray [0][0] = 10; dynamicArray [0][1] = 20; dynamicArray [1][0] = 13; dynamicArray [1][1] = 16; dynamicArray [2][0] = 7; dynamicArray [2][1] = 30; dynamicArray [3][0] = 15; dynamicArray [3][1] = 34; dynamicArray [4][0] = 25; dynamicArray [4][1] = 4; dataset-AddSerie((double *) *dynamicArray, WXSIZEOF(dynamicArray)); But it doesnt work correctly. I mean point arent drawn. I wonder if there is any possibility that I can "cheat" that method and give it dynamic array in way it understands it and will read data from correct place thanks for help

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  • C#/DataSet: Create and bind a custom column/property in a DataSet`s DataTable in the XXXDataSet.cs

    - by msfanboy
    Hello, I have a DataSet with a DataTable having the columns Number and Description. I do not want to bind both properties to a BindingSource bound again to 2 controls. What I want is a 3rd column in the DataTable called NumberDescription which is a composition of Number and Description. This property is bound only to 1 control/BindingSource`s property not 2. There is the partial XXXDataSet.Designer.cs file and the partial XXXDataSet.cs file. Of course I have defined the public string NumberDescription {get (doing some checks here;set (doing also some checks here} in the XXXDataSet.cs file. But all this does not bind my new property/Column to the BindingSource the DataTable is bound to because the DataSet does not know the new column/property. To make this new property/column known I could add a new column to the DataTAble in the DataSet designer view naming it NumberDescription. At least I see know the new property in the listing of the BindingSource so I can choose it. But all that did not help?? So how do I do that stuff properly? Should I call the NumberDescription Property in the Number AND Description Property ?

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  • Considering moving from Java/Spring MVC to Grails

    - by MDS
    I'm currently using Java & Spring (MVC) to create a webapp, and I'm considering moving to Grails. I'd appreciate feedback/insight on the following: I have multiple application contexts in the current Java/Spring webapp that I load through the web.xml ContextLoaderListener; is it possible to have multiple application contexts in Grails? If, yes, how? This webapp extensively uses a CXF restful web service and the current Java/Spring webapp uses the bundled CXF HTTP client. Can I continue to use the (Java) CXF HTTP Client in Grails? I implemented Spring Security using a custom implementation of UserDetails and UserDetailsService, can I re-use these implementations in Grails "as is" or must I re-implement them? There is an instance where I've relied on Spring's jdbc template (rather than the available ORM) and an additional data source I defined in app context, can I re-use this in Grails? I plan on using Maven as the project management tool; are there any issues of using Maven with Grails where there is a combination of groovy and java?

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  • SCons and dependencies for python function generating source

    - by elmo
    I have an input file data, a python function parse and a template. What I am trying to do is use parse function to get dictionary out of data and use that to replace fields in template. Now to make this a bit more generic (I perform the same action in few places) I have defined a custom function to do so. Below is definition of custom builder and values is a dictionary with { 'name': (data_file, parse_function) } (you don't really need to read through this, I simply put it here for completeness). def TOOL_ADD_FILL_TEMPLATE(env): def FillTemplate(env, output, template, values): out = output[0] subs = {} for name, (node, process) in values.iteritems(): def Process(env, target, source): with open( env.GetBuildPath(target[0]), 'w') as out: out.write( process( source[0] ) ) builder = env.Builder( action = Process ) subs[name] = builder( env, env.GetBuildPath(output[0])+'_'+name+'_processed.cpp', node )[0] def Fill(env, target, source): values = dict( (name, n.get_contents()) for name, n in subs.iteritems() ) contents = template[0].get_contents().format( **values ) open( env.GetBuildPath(target[0]), 'w').write( contents ) builder = env.Builder( action = Fill ) builder( env, output[0], template + subs.values() ) return output env.Append(BUILDERS = {'FillTemplate': FillTemplate}) It works fine when it comes to checking if data or template changed. If it did it rebuilds the output. It even works if I edit process function directly. However if my process function looks like this: def process( node ): return subprocess(node) and I edit subprocess the change goes unnoticed. Is there any way to get correct builds without making process functions being always invoked?

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  • Can't declare an abstract method private....

    - by Zombies
    I want to do this, yet I can't. Here is my scenario and rational. I have an abstract class for test cases that has an abstract method called test(). The test() method is to be defined by the subclass; it is to be implemented with logic for a certain application, such as CRMAppTestCase extends CompanyTestCase. I don't want the test() method to be invoked directly, I want the super class to call the test() method while the sub class can call a method which calls this (and does other work too, such as setting a current date-time right before the test is executed for example). Example code: public abstract class CompanyTestCase { //I wish this would compile, but it cannot be declared private private abstract void test(); public TestCaseResult performTest() { //do some work which must be done and should be invoked whenever //this method is called (it would be improper to expect the caller // to perform initialization) TestCaseResult result = new TestCaseResult(); result.setBeginTime(new Date()); long time = System.currentTimeMillis(); test(); //invoke test logic result.setDuration(System.currentTimeMillis() - time); return result; } } Then to extend this.... public class CRMAppTestCase extends CompanyTestCase { public void test() { //test logic here } } Then to call it.... TestCaseResult result = new CRMAppTestCase().performTest();

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  • Magento, 1 db field not saved

    - by david parloir
    Hi there, I have a problem with 1 field of the db. With this code: $expireMonth = Mage::getStoreConfig('points_options/config_points/expiration_period', Mage::app()->getStore()->getId()); if (!is_null($expireMonth) && ($expireMonth > 0)) { $expireDate = date("Y-m-d H:i:s", strtotime("+" . $expireMonth . " month")); } else { $expireDate = NULL; } //die($expireDate); //store in points history table $this->_pointsModel->setCustomerId($this->_customer->getId()) ->setOrdersId('welcome') ->setPointsPending($pointsForNewCustomer) ->setPointsComment(Mage::helper('points')->__('welcome points')) ->setDateAdded(date('Y-m-d H:i:s')) ->setPointsStatus(2)//confirmed ->setPointsType('WE') ->setStoreId(Mage::app()->getStore()->getId()) ->setExpireDate($expireDate) ->save(); every field is saved in the table, except for expire_date. If I uncoment the die($expireData), I see the correct value, something like 2012-01-13 13:21:12. The filed is defined as: `expire_date` datetime NULL Any thaughts? edit: the solution is: $expireDate = date("Y-m-d H:i:s", strtotime("+" . $expireMonth . " months")); check out the "s" in my strtotime expression

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  • Why is joining two vectors simply not working?

    - by Jim
    I have two vectors of MyObj structs. MyObj is defined as follows: struct MyObj { float x, y; unsigned int data[8]; unsigned int tmp[1]; MyObj(const MyObj &m) { x = m.x; y = m.y; tmp[0] = 0; for (int i = 0; i < 8; ++i) { data[i] = m.data[i]; } } }; I then have two vectors... vector<MyObj> v1; vector<MyObj> v2; // both get data eventually. v1.insert(v1.end(), v2.begin(), v2.end()); v2 has 3535004 elements in my experiment. v1 is similarly sized. I've also tried building a new vector and just using .push_back to build it from both vectors. Essentially, when I try to merge the two vectors I just get an error from visual studio saying "Debug error! R6010, abort() has been called". Very non-useful... So my question is: what could be causing this error, and how can I solve it? Thank you

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  • On counting pairs of words that differ by one letter

    - by Quintofron
    Let us consider n words, each of length k. Those words consist of letters over an alphabet (whose cardinality is n) with defined order. The task is to derive an O(nk) algorithm to count the number of pairs of words that differ by one position (no matter which one exactly, as long as it's only a single position). For instance, in the following set of words (n = 5, k = 4): abcd, abdd, adcb, adcd, aecd there are 5 such pairs: (abcd, abdd), (abcd, adcd), (abcd, aecd), (adcb, adcd), (adcd, aecd). So far I've managed to find an algorithm that solves a slightly easier problem: counting the number of pairs of words that differ by one GIVEN position (i-th). In order to do this I swap the letter at the ith position with the last letter within each word, perform a Radix sort (ignoring the last position in each word - formerly the ith position), linearly detect words whose letters at the first 1 to k-1 positions are the same, eventually count the number of occurrences of each letter at the last (originally ith) position within each set of duplicates and calculate the desired pairs (the last part is simple). However, the algorithm above doesn't seem to be applicable to the main problem (under the O(nk) constraint) - at least not without some modifications. Any idea how to solve this?

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  • "pseudo-atomic" operations in C++

    - by dan
    So I'm aware that nothing is atomic in C++. But I'm trying to figure out if there are any "pseudo-atomic" assumptions I can make. The reason is that I want to avoid using mutexes in some simple situations where I only need very weak guarantees. 1) Suppose I have globally defined volatile bool b, which initially I set true. Then I launch a thread which executes a loop while(b) doSomething(); Meanwhile, in another thread, I execute b=true. Can I assume that the first thread will continue to execute? In other words, if b starts out as true, and the first thread checks the value of b at the same time as the second thread assigns b=true, can I assume that the first thread will read the value of b as true? Or is it possible that at some intermediate point of the assignment b=true, the value of b might be read as false? 2) Now suppose that b is initially false. Then the first thread executes bool b1=b; bool b2=b; if(b1 && !b2) bad(); while the second thread executes b=true. Can I assume that bad() never gets called? 3) What about an int or other builtin types: suppose I have volatile int i, which is initially (say) 7, and then I assign i=7. Can I assume that, at any time during this operation, from any thread, the value of i will be equal to 7? 4) I have volatile int i=7, and then I execute i++ from some thread, and all other threads only read the value of i. Can I assume that i never has any value, in any thread, except for either 7 or 8? 5) I have volatile int i, from one thread I execute i=7, and from another I execute i=8. Afterwards, is i guaranteed to be either 7 or 8 (or whatever two values I have chosen to assign)?

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  • using same ids for many tags?

    - by gaurav rathor
    here is the example code that i was testing and i got confused that every one says that we can use or we should use only one time per id but i have testes using using it multiple times but its giving me the correct output. so what should i do. it is kinda working same like class for me in this example code: <html> <head> <style> #exampleID1 { background-color: blue; } #exampleID2 { text-transform: uppercase; } </style> </head> <body> <p id="exampleID1">This paragraph has an ID name of "exampleID1" and has a blue CSS defined background.</p> <p id="exampleID2">This paragraph has an ID name of "exampleID2" and has had its text transformed to uppercase letters.</p> <address id="exampleID1"> Written by W3Schools.com<br /> <a href="mailto:[email protected]">Email us</a><br /> Address: Box 564, Disneyland<br /> Phone: +12 34 56 78 </address> <blockquote id="exampleID1"> Here is a long quotation here is a long quotation here is a long quotation here is a long quotation here is a long quotation here is a long quotation here is a long quotation here is a long quotation here is a long quotation. </blockquote> </body> </html> please see the above code and answer me that why we should not use id selector two times in a page while its working fine.

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  • How do I pass references as method parameters across AppDomains?

    - by Thiado de Arruda
    I have been trying to get the following code to work(everything is defined in the same assembly) : namespace SomeApp{ public class A : MarshalByRefObject { public byte[] GetSomeData() { // } } public class B : MarshalByRefObject { private A remoteObj; public void SetA(A remoteObj) { this.remoteObj = remoteObj; } } public class C { A someA = new A(); public void Init() { AppDomain domain = AppDomain.CreateDomain("ChildDomain"); string currentAssemblyPath = Assembly.GetExecutingAssembly().Location; B remoteB = domain.domain.CreateInstanceFromAndUnwrap(currentAssemblyPath,"SomeApp.B") as B; remoteB.SetA(someA); // this throws an ArgumentException "Object type cannot be converted to target type." } } } What I'm trying to do is pass a reference of an 'A' instance created in the first AppDomain to the child domain and have the child domain execute a method on the first domain. In some point on 'B' code I'm going to call 'remoteObj.GetSomeData()'. This has to be done because the 'byte[]' from 'GetSomeData' method must be 'calculated' on the first appdomain. What should I do to avoid the exception, or what can I do to achieve the same result?

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  • A basic load test question

    - by user236131
    I have a very basic load test question. I am running a load test using VSTS 2008 and I have test rig with controller + 10 agents. This load test is against a SharePoint farm I have. My goal of the load test is to find out the resource utilization on web+app+db tiers of my farm for any given load scenario. An example of a load scenario is Usage profile: Average collaboration (as defined by SCCP) User Load: 500 (using step load pattern=a step of 50 every 2 mins and a warm up time of 2mins for every step) Think time: 0 Load duration: 8hrs Now, the question is: Is it fair to expect that metrics like Requests/sec, %processor time on web front end / App / DB, Test/sec, and etc become flat or enter a steady state at one point in time during the load test. Like I said, the goal is not to create a bottleneck but to only measure the utilization of resources by the above load profile. I am asking this question because I see something different. At one point in the load test, requests/sec becomes more or less flat. But processor utilization on the web/DB servers keeps increasing. After digging through the data a bit, I see that "tests running" counter also steadily increased over time. So, if I run the load test for more than 8hrs, %processor may go up further. This way, I don't know what to consider as the load excreted by the load profile. What does this "tests running" counter really signify? How is this different from tests/sec? Another question is: how can I find out why "tests running" counter shows an increase overtime? Thanks for your time

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  • Infile incomplete type error

    - by kd7vdb
    I am building a program that takes a input file in this format: title author title author etc and outputs to screen title (author) title (author) etc The Problem I am currently getting is a error "ifstream infile has incomplee type and cannot be defined" #include <iostream> #include <string> #include <ifstream> using namespace std; string bookTitle [14]; string bookAuthor [14]; int loadData (string pathname); void showall (int counter); int main () { int counter; string pathname; cout<<"Input the name of the file to be accessed: "; cin>>pathname; loadData (pathname); showall (counter); } int loadData (string pathname) // Loads data from infile into arrays { ifstream infile; int counter = 0; infile.open(pathname); //Opens file from user input in main if( infile.fail() ) { cout << "File failed to open"; return 0; } while (!infile.eof()) { infile >> bookTitle [14]; //takes input and puts into parallel arrays infile >> bookAuthor [14]; counter++; } infile.close; } void showall (int counter) // shows input in title(author) format { cout<<bookTitle<<"("<<bookAuthor<<")"; } Thanks ahead of time, kd7vdb

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