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  • Linked List push()

    - by JKid314159
    The stack is initialized with a int MaxSize =3. Then I push one int onto the list. " Pushed:" is returned to the console. Program crashes here. I think my logic is flawed but unsure. Maybe an infinite loop or unmet condition? Thanks for your help. I'm trying to traverse the list to the last node in the second part of the full() method. I implemented this stack as array based so must implement this method full() as this method is inside of main class. while(!stacker.full()) { cout << "Enter number = "; cin >> intIn; stacker.push(intIn); cout << "Pushed: " << intIn << endl; }//while Call to LinkListStack.cpp to class LinkList full(). int LinkList::full() { if(head == NULL) { top = 0; } else { LinkNode * tmp1; LinkNode * tmp2; tmp1 = head; while(top != MaxSize) { if(tmp1->next != NULL){ tmp2 = tmp1->next; tmp1 = tmp2; ++top; }//if }//while }//else return (top + 1 == MaxSize); }

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  • Rails - Help scoring an online quiz in RoR

    - by ChrisWesAllen
    I'm trying to grade a quiz application I would like to make. I have a questions model with and ask(the actual question), 4 choices(a-d), and a correct answer(string). In the view I have the 4 question being diplayed then the correct answer choice (This is just a test for functionality) and then I created a text_field to accept the users answer choice and a button to refresh the index action which has the scoring logic, for now.. --Do I need to put the text_field within a form_tag? <p>1. <%= h @question.q1 %></p> <p>2. <%= h @question.q2 %></p> <p>3. <%= h @question.q3 %></p> <p>4. <%= h @question.q4 %></p> <p>Answer: <%= h @question.correct %></p> <%= text_field_tag :choice, params[:choice] %> <%= button_to "Grade", {:controller => 'site', :action => "index"} %> <p> <%= @answer %></p> Heres the index controller action def index @question = Question.find(1) if @question.correct == params[:choice] @answer = 'right' else @answer = 'wrong' end end Its not really working. The textfield is supposed to take a letter choice like 'a' or 'c' and compare it with the correct answer in the database. I would love this to work by radiobuttons, but I'm a newbie to rails so I thought I'd take baby steps. So if anyone can help me with how to fix this by string, or preferably by radiobuttons, I'd really appreciate it.

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  • Reversible numerical calculations in Prolog

    - by user8472
    While reading SICP I came across logic programming chapter 4.4. Then I started looking into the Prolog programming language and tried to understand some simple assignments in Prolog. I found that Prolog seems to have troubles with numerical calculations. Here is the computation of a factorial in standard Prolog: f(0, 1). f(A, B) :- A > 0, C is A-1, f(C, D), B is A*D. The issues I find is that I need to introduce two auxiliary variables (C and D), a new syntax (is) and that the problem is non-reversible (i.e., f(5,X) works as expected, but f(X,120) does not). Naively, I expect that at the very least C is A-1, f(C, D) above may be replaced by f(A-1,D), but even that does not work. My question is: Why do I need to do this extra "stuff" in numerical calculations but not in other queries? I do understand (and SICP is quite clear about it) that in general information on "what to do" is insufficient to answer the question of "how to do it". So the declarative knowledge in (at least some) math problems is insufficient to actually solve these problems. But that begs the next question: How does this extra "stuff" in Prolog help me to restrict the formulation to just those problems where "what to do" is sufficient to answer "how to do it"?

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  • Sending buffered images between Java client and Twisted Python socket server

    - by PattimusPrime
    I have a server-side function that draws an image with the Python Imaging Library. The Java client requests an image, which is returned via socket and converted to a BufferedImage. I prefix the data with the size of the image to be sent, followed by a CR. I then read this number of bytes from the socket input stream and attempt to use ImageIO to convert to a BufferedImage. In abbreviated code for the client: public String writeAndReadSocket(String request) { // Write text to the socket BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())); bufferedWriter.write(request); bufferedWriter.flush(); // Read text from the socket BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream())); // Read the prefixed size int size = Integer.parseInt(bufferedReader.readLine()); // Get that many bytes from the stream char[] buf = new char[size]; bufferedReader.read(buf, 0, size); return new String(buf); } public BufferedImage stringToBufferedImage(String imageBytes) { return ImageIO.read(new ByteArrayInputStream(s.getBytes())); } and the server: # Twisted server code here # The analog of the following method is called with the proper client # request and the result is written to the socket. def worker_thread(): img = draw_function() buf = StringIO.StringIO() img.save(buf, format="PNG") img_string = buf.getvalue() return "%i\r%s" % (sys.getsizeof(img_string), img_string) This works for sending and receiving Strings, but image conversion (usually) fails. I'm trying to understand why the images are not being read properly. My best guess is that the client is not reading the proper number of bytes, but I honestly don't know why that would be the case. Side notes: I realize that the char[]-to-String-to-bytes-to-BufferedImage Java logic is roundabout, but reading the bytestream directly produces the same errors. I have a version of this working where the client socket isn't persistent, ie. the request is processed and the connection is dropped. That version works fine, as I don't need to care about the image size, but I want to learn why the proposed approach doesn't work.

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  • JAX-RS --- How to return JSON and HTTP Status code together?

    - by masato-san
    I'm writing REST web app (Netbean6.9, JAX-RS, Toplink-essential) and trying to return JSON and Http status code. I have code ready and working just to return JSON when HTTP GET Method is called from client. Code snippet @Path("get/id") @GET @Produces("application/json") public M_?? getMachineToUpdate(@PathParam("id") String id) { //some code to return JSON . . return myJson But I also want to return HTTP status code (500, 200, 204 etc) along with returning JSON. I tried using HttpServletResponse object, response.sendError("error message", 500); But this made browser to think it's real 500 so output web page was regular Http 500 error page. What I want to is just to return status code so that my Javascript on client side can handle some logic depending on what HTTP status code is returned. (maybe just to display the error code and message on html page.) Is it possible to do so? or should HTTP status code not be used for such thing?

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  • Integration transport choice (Oracle + SQL Server)

    - by lak-b
    We have several systems with Oracle (A) and SQL Server (B) databases on backend. I have to consolidate data from those systems into the new SQL Server database. Something like that: (A) =>|---------------| | some software | => SQL Server (B) =>|---------------| where some software is: transport (A and B systems located in the network) processing business logic (custom .NET code) Due to first point, I need some queue software or something similar (like MSMQ, Service Broker or something). In another hand, I can implement a web-service instead of queue. (A) =>|---------------|-------------| | queue/service | custom code | => SQL Server (B) =>|---------------|-------------| The question is: which queue/transport framework should I use with Oracle and SQL Server databases? It would be nice, if I can post messages to MSMQ in both Oracle and SQL Server stored procedures (can I?) It would be nice, if I can call a web-service in both Oracle and SQL Server stored procedures (can I?) It would be nice, if I can use something similar in both Oracle and SQL Server stored procedures (what exactly?) What software should I prefer to my requirements?

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  • How to write this snippet in Python?

    - by morpheous
    I am learning Python (I have a C/C++ background). I need to write something practical in Python though, whilst learning. I have the following pseudocode (my first attempt at writing a Python script, since reading about Python yesterday). Hopefully, the snippet details the logic of what I want to do. BTW I am using python 2.6 on Ubuntu Karmic. Assume the script is invoked as: script_name.py directory_path import csv, sys, os, glob # Can I declare that the function accepts a dictionary as first arg? def getItemValue(item, key, defval) return !item.haskey(key) ? defval : item[key] dirname = sys.argv[1] # declare some default values here weight, is_male, default_city_id = 100, true, 1 # fetch some data from a database table into a nested dictionary, indexed by a string curr_dict = load_dict_from_db('foo') #iterate through all the files matching *.csv in the specified folder for infile in glob.glob( os.path.join(dirname, '*.csv') ): #get the file name (without the '.csv' extension) code = infile[0:-4] # open file, and iterate through the rows of the current file (a CSV file) f = open(infile, 'rt') try: reader = csv.reader(f) for row in reader: #lookup the id for the code in the dictionary id = curr_dict[code]['id'] name = row['name'] address1 = row['address1'] address2 = row['address2'] city_id = getItemValue(row, 'city_id', default_city_id) # insert row to database table finally: f.close() I have the following questions: Is the code written in a Pythonic enough way (is there a better way of implementing it)? Given a table with a schema like shown below, how may I write a Python function that fetches data from the table and returns is in a dictionary indexed by string (name). How can I insert the row data into the table (actually I would like to use a transaction if possible, and commit just before the file is closed) Table schema: create table demo (id int, name varchar(32), weight float, city_id int); BTW, my backend database is postgreSQL

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  • Simulating a contains If-Else using RewriteCond

    - by hlissner
    Hi! I'm trying to get my head around RewriteCond, and want to rewrite any requests either to a static html page (if it exists), or to a specific index.php (so long as the requested file doesn't exist). To illustrate the logic: if HTTP_HOST is '(www\.)?mydomain.com' if file exists: "/default/static/{REQUEST_URI}.html", then rewrite .* to /default/static/{REQUEST_URI}.html else if file exists: {REQUEST_FILENAME}, then do not rewrite else rewrite .* to /default/index.php I don't seem to have much trouble doing it when I don't need to test for the HTTP_HOST. Ultimately, this one .htaccess file will be handling requests for several domains. I know I could get around this with vhosts, but I'd like to figure out how to do it this way. Here's where I am at now: RewriteCond %{HTTP_HOST} ^(www\.)?mydomain\.com$ [NC] RewriteCond /default/static/%{REQUEST_URI}.html -f RewriteRule . /default/static/%{REQUEST_URI}.html [L,NC] RewriteCond %{REQUEST_FILENAME} !-f RewriteRule . /default/index.php [L,QSA] I'm not too familiar with some of the other flags, will any of them be of use here (like chain|C, next|N or skip|S)? Thanks in advance!

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  • structDelete doesn't affect the shallow copy?

    - by Travis
    I was playing around onError so I tried to create an error using a large xml document object. <cfset XMLByRef = variables.parsedXML.XMLRootElement.XMLChildElement> <cfset structDelete(variables.parsedXML, "XMLRootElement")> <cfset startXMLShortLoop = getTickCount()> <cfloop from = "1" to = "#arrayLen(variables.XMLByRef)#" index = "variables.i"> <cfoutput>#variables.XMLByRef[variables.i].id.xmltext#</cfoutput><br /> </cfloop> <cfset stopXMLShortLoop = getTickCount()> I expected to get an error because I deleted the structure I was referencing. From LiveDocs: Variable Assignment - Creates an additional reference, or alias, to the structure. Any change to the data using one variable name changes the structure that you access using the other variable name. This technique is useful when you want to add a local variable to another scope or otherwise change a variable's scope without deleting the variable from the original scope. instead I got 580df1de-3362-ca9b-b287-47795b6cdc17 25a00498-0f68-6f04-a981-56853c0844ed ... ... ... db49ed8a-0ba6-8644-124a-6d6ebda3aa52 57e57e28-e044-6119-afe2-aebffb549342 Looped 12805 times in 297 milliseconds <cfdump var = "#variables#"> Shows there's nothing in the structure, just parsedXML.xmlRoot.xmlName with the value of XMLRootElement. I also tried <cfset structDelete(variables.parsedXML.XMLRootElement, "XMLChildElement")> as well as structClear for both. More information on deleting from the xml document object. http://help.adobe.com/en_US/ColdFusion/9.0/Developing/WSc3ff6d0ea77859461172e0811cbec22c24-78e3.html Can someone please explain my faulty logic? Thanks.

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  • Seam @Factory in abstract base class?

    - by Shadowman
    I've got a series of web actions I'm implementing in Seam to perform create, read, update, etc. operations. For my read/update/delete actions, I'd like to have individual action classes that all extend an abstract base class. I'd like to put the @Factory method in the abstract base class to retrieve the item that is to be acted upon. For example, I have this as the base class: public abstract class BaseAction { @In(required=false)@Out(required=false) private MyItem item=null; public MyItem getItem(){...} public void setItem(...){...} @Factory("item") public void initItem(){...} } My subclasses would extend BaseAction, so that I don't have to repeat the logic to load the item that is to be viewed, deleted, updated, etc. However, when I start my application, Seam throws errors saying I have declared multiple @Factory's for the same object. Is there any way around this? Is there any way to provide the @Factory in the base class without encoutnering these errors?

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  • How to embed a precharged collection of non-entity forms in symfony2

    - by metalvarez
    I want to embed a collection of precharged non-entity forms, here is the code, first is the parent form buildForm method. public function buildForm(FormBuilderInterface $builder, array $options) { $builder->add("example1")->add("example2"); $builder->addEventListener(FormEvents::PRE_SET_DATA, function (FormEvent $event) { /*some logic to do before adding the collection of forms*/ $form->add('aclAccess', 'collection', array( 'type' => new ChildFormType(), 'allow_add' => true, 'mapped' => false, 'data' => /* I dont know how to precharge a collection of non-entity forms*/ )); }); } now the child form public function buildForm (FormBuilderInterface $builder, array $options) { $builder->add("test1", "text", array("read_only" => true, "data" => "test")); $builder->->add("test2", "choice", array( 'choices' => array('opt1' => 'Opt1', 'opt2' => 'Opt2'), 'multiple' => true, 'expanded' => true )); } so basicly i want to manage those child options in the test2 field as separated forms, each option group will depend on the value of the test1 field, i know this can be done by coding everythin in twig without form classes but i think having form classes its the best practice to run phpunit test, for maintainability, etc ...

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  • Is there a max recommended size on bundling js/css files due to chunking or packet loss?

    - by George Mauer
    So we all have heard that its good to bundle your javascript. Of course it is, but it seems to me that the story is too simple. See if my logic makes sense here. Obviously fewer HTTP requests is fewer round trips and hence better. However - and I don't know much about bare http - aren't http responses sent in chunks? And if a file is larger than one of those chunks doesn't it have to be downloaded as multiple (possibly synchronous?) round trips? As opposed to this, several requests for files just under the chunking size would arrive much quicker since modern web browsers download resources like javascripts in parallel. Even if chunking is not an issue, it seems like there would be some max recommended size just due to likelyhood of packet loss alone since a bundled file must wait till it is entirely downloaded to execute, versus the more lenient native rule that scripts must execute in order. Obviously there's also matters of browser caching and code volatility to consider but can someone confirm this or explain why I'm off base? Does anyone have any numbers to put to it?

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  • VB.NET editing existing that with a form

    - by user127147
    Hi there, I have a simple questions that puzzles me. I need a little bit of refreashment with VB as I have been away for a while. I have a form that adds new contacts. New contacts are added by pressing an appropriate button and they appear as an entry in the list on the form. I try now to add an edit button that will edit existing entries. User will select a given entry on the list and press edit button and will be presented with an appropriate form (AddContFrm). Right now it simply adds another entry with the same title. Logic is handled in a class called Contact.vb Here is my code. Public Class Contact Public Contact As String Public Title As String Public Fname As String Public Surname As String Public Address As String Private myCont As String Public Property Cont() Get Return myCont End Get Set(ByVal value) myCont = Value End Set End Property Public Overrides Function ToString() As String Return Me.Cont End Function Sub NewContact() FName = frmAddCont.txtFName.ToString frmStart.lstContact.Items.Add(FName) frmAddCont.Hide() End Sub Public Sub Display() Dim C As New Contact 'C.Cont = InputBox("Enter a title for this contact.") C.Cont = frmAddCont.txtTitle.Text C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text 'frmStart.lstContact.Items.Add(C.Cont.ToString) frmStart.lstContact.Items.Add(C) End Sub End Class AddContFrm Public Class frmAddCont Public Class ControlObject Dim Title As String Dim FName As String Dim SName As String Dim Address As String Dim TelephoneNumber As Integer Dim emailAddress As String Dim Website As String Dim Photograph As String End Class Private Sub btnConfirmAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConfirmAdd.Click Dim C As New Contact C.Display() Me.Hide() End Sub Private Sub frmAddCont_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load End Sub End Class and frmStart.vb Public Class frmStart Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click frmAddCont.Show() End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDel.Click Dim DelCont As Contact DelCont = Me.lstContact.SelectedItem() lstContact.Items.Remove(DelCont) End Sub Private Sub lstContact_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstContact.SelectedIndexChanged End Sub Private Sub btnEdit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEdit.Click Dim C As Contact If lstContact.SelectedItem IsNot Nothing Then C = DirectCast(lstContact.SelectedItem, Contact) C.Display() End If End Sub End Class

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  • Object Design: How to Organize/Structure a "Collection Class"

    - by CrimsonX
    I'm currently struggling to understand how I should organize/structure a class which I have already created. The class does the following: As its input in the constructor, it takes a collection of logs In the constructor it validates and filters the logs through a series of algorithms implementing my business logic After all filtering and validation is complete, it returns a collection (a List) of the valid and filtered logs which can be presented to the user graphically in a UI. Here is some simplified code describing what I'm doing: class FilteredCollection { public FilteredCollection( SpecialArray<MyLog> myLog) { // validate inputs // filter and validate logs in collection // in end, FilteredLogs is ready for access } Public List<MyLog> FilteredLogs{ get; private set;} } However, in order to access this collection, I have to do the following: var filteredCollection = new FilteredCollection( secialArrayInput ); //Example of accessing data filteredCollection.FilteredLogs[5].MyLogData; Other key pieces of input: I foresee only one of these filtered collections existing in the application (therefore should I make it a static class? Or perhaps a singleton?) Testability and flexibility in creation of the object is important (Perhaps therefore I should keep this an instanced class for testability?) I'd prefer to simplify the dereferencing of the logs if at all possible, as the actual variable names are quite long and it takes some 60-80 characters to just get to the actual data. My attempt in keeping this class simple is that the only purpose of the class is to create this collection of validated data. I know that there may be no "perfect" solution here, but I'm really trying to improve my skills with this design and I would greatly appreciate advice to do that. Thanks in advance.

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  • Spring security - same page to deliver different content based on user role

    - by Ramesh
    Hello, i tried to search for any previous post related to my issue but couldnt find any. I have a scenario where in page handles 3 different scenarios and one of them not working. This page returns different content depending on if the user is authenticated or anonymous. localhost:8080/myApp/muUrl?test=authenticatedContent - used for Scenario 1 & 2 localhost:8080/myApp/muUrl?test=anonymousContent - used for Scenario 3 Scenario: 1) Authenticated user accesing the page url - the user gets displayed correct information. Works fine 2) Anonymous user accesing page URL with parameters that requires authentication - If anonymous, there is second level of check on the content they are accessing. for example, based on the GET parameters, there is custom logic to determine if the user has to be authenticated. In which case the page gets redirected to login page (WORKS fine). 3) Anonymous user accessing page URL with parameters that doesnt need authentication - in this case i get the SAvedRequest and redirect to the URL which is taking me to an infinite loop. Am i missing something very obvious or is there a way in AuthenticationProcessFilterEntryPoint to say "DON'T redirect to LOGIN page but process it" ? thanks.

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  • How can I send rich emails using the user's mail client ?

    - by Brann
    I need my .net program to send rich emails (usually containing table data, around 20 columns x 10 rows) using the user's mail infrastructure, allowing him to review/edit the mail before sending it, and storing the mail in his 'sent items' folder. mailto: seems the obvious choice, but unfortunately, it doesn't support neither attachments nor html bodies. It seems some clients support some extra features (e.g. Outlook 97 used to support a &Attach tag, but this is not the case for more recent versions). I could use mailto and try to format the text body to look nice (using tabs, etc), but this isn't really elegant and wouldn't support huge data. using automation seems a very huge task, as I would need to automate dozens of clients (4 or 5 versions of outlook, lotusnotes, thunderbid, etc.) ... This would be a huge task and it's not really my core business ... I could send emails through code and write my own mail form to let the user edit the mail, but this would have a lot of drawbacks : the user would need to manually configure the mail server settings he wouldn't have access to his contact directory the mail wouldn't be sent in his sent items folder This seems a quite common issue, but I haven't found any satisfying solution yet ; does someone knows of a library supporting this (ie containing automation logic for most mainstream email clients?). Or an alternative to mailto ?

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  • Is it possible to filter data used by pivot table based on filtering the rows in a source table in Excel?

    - by Geoffrey Stoel
    I have developed a dashboard in Excel 2007 that uses one source table in a sheet (being filled with a query on our data warehouse) and multiple pivot tables making different cross sections on this data. I use the GETPIVOTDATA in almost a hundred formulas to give me the right value for a specific indicator in my dashboard. This all works fine. However I now have received the question to make the dashboard for 5 different segments. As you can imagine I don't want to create 5 different workbooks for this and need to maintain the dashboard logic on all of them. So my question is the following. Is it possible to automatically (through VBA or any other means) filter the results in my source table which is the source for my pivot tables and thus for my dashboard values. So schematically: DATABASE_VIEW -- SOURCE_TABLE -- 12 pivot tables -- 100 GETPIVOTDATA functions Preferably I would like to load all the segments in the source_table (one view on my database) and then filter the data in the source table, which results in filterd source_dat for my pivots. This way I can (without requerying the db) quickly change between segments in the dashboards (refreshing pivots only). Data in the source table has the column: CUSTOMER_SEGMENT available to filter upon. Any help is appreciated. Geoffrey

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  • Python Multiprocessing Question

    - by Avan
    My program has 2 parts divided into the core and downloader. The core handles all the app logic while the downloader just downloads urls. Right now, I am trying to use the python multiprocessing module to accomplish the task of the core as a process and the downloader as a process. The first problem I noticed was that if I spawn the downloader process from the core process so that the downloader is the child process and the core is the parent, the core process(parent) is blocked until the child is finished. I do not want this behaivor though. I would like to have a core process and a downloader process that are both able to execute their code and communicate between each other. example ... def main(): jobQueue = Queue() jobQueue.put("http://google.com) d = Downloader(jobQueue) p = Process(target=d.start()) p.start() if __name__ == '__main__': freeze_support() main() where Downloader's start() just takes the url out of the queue and downloads it. In order to have the 2 processes unblocked, would I need to create 2 processes from the parent process and then share something between them?

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  • When are predicates appropriate and what is the best pattern for usage

    - by Maxim Gershkovich
    When are predicates appropriate and what is the best pattern for usage? What are the advantages of predicates? It seems to me like most cases where a predicate can be employed a tight loop would accomplish the same functionality? I don’t see a reusability argument given you will probably only implement a predicate in one method right? They look and feel nice but besides that they seem like you would only employ them when you need a quick hack on the collection classes? UPDATE But why would you be rewriting the tight loop again and again? In my mind/code when it comes to collections I always end up with something like Class Person End Class Class PersonList Inherits List(Of Person) Function FindByName(Name) as Person tight loop.... End Function End Class @Ani By that same logic I could implement the method as such Class PersonList Inherits List(Of Person) Function FindByName(Name) as PersonList End Function Function FindByAge(Age) as PersonList End Function Function FindBySocialSecurityNumber(SocialSecurityNumber) as PersonList End Function End Class And call it as such Dim res as PersonList = MyList.FindByName("Max").FindByAge(25).FindBySocialSecurityNumber(1234) and the result along with the amount of code and its reusability is largely the same, no? I am not arguing just trying to understand.

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  • Where do objects merge/join data in a 3-tier model?

    - by BerggreenDK
    Its probarbly a simple 3-tier problem. I just want to make sure we use the best practice for this and I am not that familiary with the structures yet. We have the 3 tiers: GUI: ASP.NET for Presentation-layer (first platform) BAL: Business-layer will be handling the logic on a webserver in C#, so we both can use it for webforms/MVC + webservices DAL: LINQ to SQL in the Data-layer, returning BusinessObjects not LINQ. DB: The SQL will be Microsoft SQL-server/Express (havent decided yet). Lets think of setup where we have a database of [Persons]. They can all have multiple [Address]es and we have a complete list of all [PostalCode] and corresponding citynames etc. The deal is that we have joined a lot of details from other tables. {Relations}/[tables] [Person]:1 --- N:{PersonAddress}:M --- 1:[Address] [Address]:N --- 1:[PostalCode] Now we want to build the DAL for Person. How should the PersonBO look and when does the joins occure? Is it a business-layer problem to fetch all citynames and possible addressses pr. Person? or should the DAL complete all this before returning the PersonBO to the BAL ? Class PersonBO { public int ID {get;set;} public string Name {get;set;} public List<AddressBO> {get;set;} // Question #1 } // Q1: do we retrieve the objects before returning the PersonBO and should it be an Array instead? or is this totally wrong for n-tier/3-tier?? Class AddressBO { public int ID {get;set;} public string StreetName {get;set;} public int PostalCode {get;set;} // Question #2 } // Q2: do we make the lookup or just leave the PostalCode for later lookup? Can anyone explain in what order to pull which objects? Constructive criticism is very welcome. :o)

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  • Semantically correct nested anchors

    - by Blackie123
    I am working on a web applicaton. And what we also create is something that could be described as inline editing. Just to portray thing I am trying to solve I use example of Facebook post. You have post like. Steve Jobs added 5 new photos Steve Jobs is link that redirects to his profile so in HTML, that would be: <div class="post-block"> <p><a href="stevejobs/" title="#">Steve Jobs</a> added 5 new photos.<p> </div> But what I want is the whole post "block" to be clickable although I want only that name to appear to be link. Normally in HTML logic would say to to this: <a href="stevejobs/" title="#"><div class="post-block"> <p><a href="stevejobs/" title="#">Steve Jobs</a> added 5 new photos.<p> </div></a> But this isn't semantically correct. Quick look to HTML 4.01 or any other standard says something like this: Links and anchors defined by the A element must not be nested; an A element must not contain any other A elements. How to create it semantically correct other than using javascript and defining div:hover state for the whole "div anchor"?

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  • How to check for a null object reference when validating forms in MVC

    - by quakkels
    Hello SO, I'm experimenting with validating forms in the asp.net MVC framework. I'm focusing on server side validation for the time being. I've come across an error that I'm not sure how to rectify. System.NullReferenceException: Object reference not set to an instance of an object. The code that throws the error is: [AcceptVerbs(HttpVerbs.Post)] public ActionResult Create([Bind(Exclude="ID")] MembersCreate mc ) { mc.Modules = ModuleListDataContext.GetModuleList(); ViewData.Model = mc; //Validation using ModelState // // //line below errors when form field is empty // if ((string)mc.Member.Username.Trim() == "") ModelState.AddModelError("Member.Username", "Username is required."); if (!ModelState.IsValid) return View(); try { // TODO: Add insert logic here return RedirectToAction("Index","Home"); } catch { return View(); } } When I put spaces in the field it performs exactly as i want, but if I leave the field blank and press submit I get the error. What's the best way to avoid this error and still validate blank form fields? Thanks all -

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  • Inorder tree traversal in binary tree in C

    - by srk
    In the below code, I'am creating a binary tree using insert function and trying to display the inserted elements using inorder function which follows the logic of In-order traversal.When I run it, numbers are getting inserted but when I try the inorder function( input 3), the program continues for next input without displaying anything. I guess there might be a logical error.Please help me clear it. Thanks in advance... #include<stdio.h> #include<stdlib.h> int i; typedef struct ll { int data; struct ll *left; struct ll *right; } node; node *root1=NULL; // the root node void insert(node *root,int n) { if(root==NULL) //for the first(root) node { root=(node *)malloc(sizeof(node)); root->data=n; root->right=NULL; root->left=NULL; } else { if(n<(root->data)) { root->left=(node *)malloc(sizeof(node)); insert(root->left,n); } else if(n>(root->data)) { root->right=(node *)malloc(sizeof(node)); insert(root->right,n); } else { root->data=n; } } } void inorder(node *root) { if(root!=NULL) { inorder(root->left); printf("%d ",root->data); inorder(root->right); } } main() { int n,choice=1; while(choice!=0) { printf("Enter choice--- 1 for insert, 3 for inorder and 0 for exit\n"); scanf("%d",&choice); switch(choice) { case 1: printf("Enter number to be inserted\n"); scanf("%d",&n); insert(root1,n); break; case 3: inorder(root1); break; default: break; } } }

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  • find contiguous stretches of equal data in a vector

    - by mariotomo
    I have a numeric vector, it contains patches of elements that are repeating, something like: R> data <- c(1,1,1,2,2,2,3,3,2,2,2,2,2,3,3,1,1,1,1,1) R> data [1] 1 1 1 2 2 2 3 3 2 2 2 2 2 3 3 1 1 1 1 1 R> I need to extract contiguous patches of elements equals to a specific value... but I'm only interested in the patch around a specific position. so, my input is: (1) the numeric vector, (2) the desired value, (3) the position. I want to return a logic vector indicating which positions satisfy the request. if at that position the data does not equal the value, I return all FALSE. possible outcomes that are not all F would be: [1] 1 1 1 2 2 2 3 3 2 2 2 2 2 3 3 1 1 1 1 1 [1] T T T F F F F F F F F F F F F F F F F F [2] F F F T T T F F F F F F F F F F F F F F [3] F F F F F F T T F F F F F F F F F F F F [4] F F F F F F F F T T T T T F F F F F F F [5] F F F F F F F F F F F F F T T F F F F F [6] F F F F F F F F F F F F F F F T T T T T

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  • WPF validation on Enter Key Up

    - by Martin
    I'm trying to validate a UI change when Enter key is pressed. The UI element is a textbox, which is data binded to a string. My problem is that the data binding hasn't updated TestText when Enter key is Up. It is only updated when I press the button which brings up a message box. /// <summary> /// Interaction logic for Window1.xaml /// </summary> public partial class Window1 : Window, INotifyPropertyChanged { String _testText = new StringBuilder("One").ToString(); public string TestText { get { return _testText; } set { if (value != _testText) { _testText = value; OnPropertyChanged("TestText"); } } } public Window1() { InitializeComponent(); myGrid.DataContext = this; } private void OnPropertyChanged(string property) { if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(property)); } } public event PropertyChangedEventHandler PropertyChanged; private void onKeyUp(object sender, KeyEventArgs e) { if (e.Key != System.Windows.Input.Key.Enter) return; System.Diagnostics.Trace.WriteLine(TestText); } private void button1_Click(object sender, RoutedEventArgs e) { MessageBox.Show(TestText); } } Window XAML: Window x:Class="VerificationTest.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Window1" Height="300" Width="300" KeyUp="onKeyUp" TextBox XAML: TextBox Name="myTextBox" Text="{Binding TestText}" Button XAML: Button Name="button1" Click="button1_Click"

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