Search Results

Search found 5377 results on 216 pages for 'explicit cast operator'.

Page 156/216 | < Previous Page | 152 153 154 155 156 157 158 159 160 161 162 163  | Next Page >

  • Postfix evaluation in C

    - by Andrewziac
    I’m taking a course in C and we have to make a program for the classic Postfix evaluation problem. Now, I’ve already completed this problem in java, so I know that we have to use a stack to push the numbers into, then pop them when we get an operator, I think I’m fine with all of that stuff. The problem I have been having is scanning the postfix expression in C. In java it was easier because you could use charAt and you could use the parseInt command. However, I’m not aware of any similar commands in C. So could anyone explain a method to read each value from a string in the form: 4 9 * 0 - = Where the equals is the signal of the end of the input. Any help would be greatly appreciated and thank you in advance :)

    Read the article

  • Java generic function for performing calculations on integer, on double?

    - by Daniel
    Is this possible? Surely if you passed in a double, any sort of function implementation code which casts an object to an Integer would not be able to work unless the cast 'Integer' was specifically used? I have a function like: public static void increment(Object o){ Integer one = (Integer)o; system.out.println(one++); } I cant see how this could be made generic for a double? I tried public static <E> void increment(E obj){ E one = (E)o; system.out.println(one++); } but it didn't like it?

    Read the article

  • Testing what a String token holds

    - by Yiwei Gao
    I am making a calculator and part of this program takes in user String input and tokenizes it (using my own implementation of a Tokenizer class). So now I have a bunch of Token objects and I would like to test each one of them to see if they hold numbers or operators. Is there a way to test to see if they hold operators (ie. +, -, *, /, =, (, ), etc.) without using if (token.equals("+") || token.equals("-") || ... and so on, for each operator? These Token objects are all of type String.

    Read the article

  • Running for loop depending on size of string vector

    - by xbonez
    I have made a string vector vector actor_; and then added elements in it using push_back. I now want to display all of them, for which I need to run a loop according to the number of elements in the vector. For that, I need to run the following loop: for (int i = 0; i < (int)actor_.size; i++) { } but this returns the following error: error C2440: 'type cast' : cannot convert from 'unsigned int (__thiscall std::vector<_Ty::* )(void) const' to 'int' 1 with 1 [ 1 _Ty=std::string 1 ] 1 There is no context in which this conversion is possible

    Read the article

  • A strange error in java generic.

    - by ???
    This is ok: Class<? extends String> stringClass = "a".getClass(); But this gets error: <T> void f(T obj) { Class<? extends T> objClass = obj.getClass(); } I know I can cast it like: <T> void f(T obj) { @SuppressWarnings("unchecked") Class<? extends T> objClass = (Class<? extends T>) obj.getClass(); } But why the previous error? Will the next release of Java 7 will support such usage?

    Read the article

  • Core Data: Detecting the type and casting it

    - by Tim Sullivan
    I have set up a Core Data model that includes an entity, Item with a 1-M relationship with the abstract entity Place, so that an item has many places. There are several entities with the parent set to Place. I want to set up several UI elements depending on the descendent place types. I have a loop that looks something like this: for (Place *place in item.places) { } ... but I'm not sure how to detect what type the place is, and how to cast it to the proper type so that I can access its properties. Thanks for any help!

    Read the article

  • Is it possible in Scala to force the caller to specify a type parameter for a polymorphic method ?

    - by Alex Kravets
    //API class Node class Person extends Node object Finder { def find[T <: Node](name: String): T = doFind(name).asInstanceOf[T] } //Call site (correct) val person = find[Person]("joe") //Call site (dies with a ClassCast inside b/c inferred type is Nothing) val person = find("joe") In the code above the client site "forgot" to specify the type parameter, as the API writer I want that to mean "just return Node". Is there any way to define a generic method (not a class) to achieve this (or equivalent). Note: using a manifest inside the implementation to do the cast if (manifest != scala.reflect.Manifest.Nothing) won't compile ... I have a nagging feeling that some Scala Wizard knows how to use Predef.<:< for this :-) Ideas ?

    Read the article

  • What does it mean when a Perl method returns a "hashref"?

    - by Uri
    I'm trying to decrypt a Perl code which I'm not familiar with, somehow related to HashRef. I'm using Amazon::S3, but my question is a general Perl question. See the code below: use Amazon::S3; my $s3 = Amazon::S3->new( ... ); my $response = $s3->buckets; Documentation (here) sais, about s3-buckets: Returns undef on error, else HASHREF of results The following line is working for me, but I don't understand why: for $b in ( @ { $response->{buckets} } ) { print "bucket: " . $b->bucket . "\n"; } I'm Puzzled by each operator on the first line. What type exactly are $response, $respone->{bucket}. Looks like the expression within the for is an array, but I don't understand this syntax: @{ ... }?

    Read the article

  • Strange C++ thread function invocation

    - by Tony
    I have the following: class DThread { virtual void run()=0; _beginthreadex(NULL,0,tfunc,this,0,&m_UIThreadID); // class itself being passed as param to thread function... static unsigned int __stdcall tfunc(void* thisptr) { static_cast<DThread*>(thisptr)->run(); return 0; } //other stuff } The run function is implemented in a derived class. Why is the function that's being called in the thread being called through a cast this pointer? Is this good practise? Can't it just be called directly? The actual function needing to run is in the derived class. My question is

    Read the article

  • How do I put logic in a View a scope or method in a Model?

    - by Angela
    I have the following in the view: <% unless contact_email.statuses.empty?%> (<%= contact_email.statuses.find(:last).status%>) <% end %> contact_email is an instance of a specific model. Could I do something like this? class ContactEmail < ActiveRecord::Base attr_accessible :contact_id, :email_id, :status, :subject, :body, :date_created, :date_sent def status unless contact_email.statuses.empty? contact_email.statuses.find(:last).status end end end is there a better way to do this? is there a way to use the || operator for a default if empty? Basically, I would like to be able to do the following in the View: <%= contact_email.status = IF there is a value, then display it, if not, show nothing.

    Read the article

  • calling a java class in a servlet

    - by kawtousse
    hi, in my servlet i called an instance of a class.java( a class that construct an html table) in order to create this table in my jsp. the servlet is like the following: String report=request.getParameter("selrep"); String datev=request.getParameter("datepicker"); String op=request.getParameter("operator"); String batch =request.getParameter("selbatch"); System.out.println("report kind was:"+report); System.out.println("date was:"+datev); System.out.println("operator:"+op); System.out.println("batch:"+batch); if(report.equalsIgnoreCase("Report Denied")) { DeniedReportDisplay rd = new DeniedReportDisplay(); rd.ConstruireReport(); } else if(report.equalsIgnoreCase("Report Locked")) { LockedReportDisplay rl = new LockedReportDisplay(); rl.ConstruireReport(); } request.getRequestDispatcher("EspaceValidation.jsp").forward(request, response); in my jsp i can not display this table even empty or full. note: exemple a class that construct denied Report has this structure: /*constructeur*/ public DeniedReportDisplay() {} /*Methodes*/ @SuppressWarnings("unchecked") public StringBuffer ConstruireReport() { StringBuffer retour=new StringBuffer(); int i = 0; retour.append("<table border = 1 width=900 id=sheet align=left>"); retour.append("<tr bgcolor=#0099FF>" ); retour.append("<label> Denied Report</label>"); retour.append("</tr>"); retour.append("<tr>"); String[] nomCols ={"Nom","Prenom","trackingDate","activity","projectcode","WAName","taskCode","timeSpent","PercentTaskComplete","Comment"}; //String HQL_QUERY = null; for(i=0;i< nomCols.length;i++) { retour.append(("<td bgcolor=#0066CC>")+ nomCols[i] + "</td>"); } retour.append("</tr>"); retour.append("<tr>"); try { s= HibernateUtil.currentSession(); tx=s.beginTransaction(); Query query = s.createQuery("select opcemployees.Nom,opcemployees.Prenom,dailytimesheet.TrackingDate,dailytimesheet.Activity," + "dailytimesheet.ProjectCode,dailytimesheet.WAName,dailytimesheet.TaskCode," + "dailytimesheet.TimeSpent,dailytimesheet.PercentTaskComplete from Opcemployees opcemployees,Dailytimesheet dailytimesheet " + "where opcemployees.Matricule=dailytimesheet.Matricule and dailytimesheet.Etat=3 " + "group by opcemployees.Nom,opcemployees.Prenom" ); for(Iterator it=query.iterate();it.hasNext();) { if(it.hasNext()){ Object[] row = (Object[]) it.next(); retour.append("<td>" +row [0]+ "</td>");//Nom retour.append("<td>" + row [1] + "</td>");//Prenom retour.append("<td>" + row [2] + "</td>");//trackingdate retour.append("<td>" + row [3]+ "</td>");//activity retour.append("<td>" + row [4] +"</td>");//projectcode retour.append("<td>" + row [5]+ "</td>");//waname retour.append("<td>" + row [6] + "</td>");//taskcode retour.append("<td>" + row [7] + "</td>");//timespent retour.append("<td>" + row [8] + "</td>");//perecnttaskcomplete retour.append("<td><input type=text /></td>");//case de commentaire } retour.append("</tr>"); } //terminer la table. retour.append ("</table>"); tx.commit(); } catch (HibernateException e) { retour.append ("</table><H1>ERREUR:</H1>" +e.getMessage()); e.printStackTrace(); } return retour; } thanks for help.

    Read the article

  • Is it possible to use the values method for a HashMap if the values are ArrayLists?

    - by Denman
    I'm stuck trying to get something to work in an assignment. I have a HashMap<Integer, ArrayList<Object>> called sharedLocks and I want to check whether a certain value can be found in any ArrayList in the HashMap. The following code obviously wouldn't work because Object[] can't be cast to ArrayList[], but it is a demonstration of the general functionality that I want. ArrayList[] values = (ArrayList[]) sharedLocks.values().toArray(); boolean valueExists = false; for (int i = 0; i < values.length; i++) { if (values[i].contains(accessedObject)) { valueExists = true; } } Is there a way for me to check every ArrayList in the HashMap for a certain value? I'm not sure how to use the values method for HashMaps in this case. Any help would be much appreciated.

    Read the article

  • Mobile web apps - Is this the right approach?

    - by Pasta
    I need to build a cross platform mobile app (iphone, android, etc). The app is for a company like a cellular operator (Tmobile, ATT). The app needs to do the following: Show previous bills (cached so that it does not have to download everytime) Need an internet connection to download newer bills, view recent data, etc. Can I build a mobile web app to handle this? I understand that there is offline storage and iPhone has good support for web apps (full screen, good icons, offline, etc). Will a web app be the best approach to take as the app requires to be online? The app will not be used by lots of people, just customers of the website who don't want to use an existing website. We are all web developers and a mobile web app looks like the best way to approach this.

    Read the article

  • Casting an object which could be null

    - by DeeMac
    DateTime? testDate = (DateTime?)arrayOfObjects[dateObject]; Does that code look ok? I attempted to use the as operator but I got the 'non-nullable' error. What I'm trying to say is that the object I'm choosing from the array is either DateTime or a null DateTime but either can be assigned to testDate. Doesn't feel right doing it this way, I think I'm missing something obvious. EDIT: I suppose it's the same as the way I could've adapted the as in the following way: DateTime? testDate = arrayOfObjects[dateObject] as DateTime?; Is either line of code the best way of handling potential nulls?

    Read the article

  • How do I get a Type[] with arguments from a MethodCallExpression?

    - by Tomas Lycken
    I'm reflecting over a class (in a unit test of said class) to make sure its members have all the required attributes. To do so, I've constructed a couple of helpers, that take an Expression as an argument. I do some checks for it, and take slightly different actions depending on what type of Expression it is, but it's basically the same. Now, my problem is that I have several methods with the same name (but different signatures), and the following code throws an AmbiguousMatchException: // TOnType is a type argument for the type where the method is declared // mce is the MethodCallExpression var m = typeof(TOnType).GetMethod(mce.Method.Name); Now, if I could add an array of Type[] with the types of the arguments to this method as a second parameter to .GetMethod(), the problem would be solved. But how do I find this Type[] array that I need? I have cast the Expression<Func<...>> to an Expression, and then to a MethodCallExpression, and in this method the contents of <...> is not known.

    Read the article

  • Linking each text word or words divided by comma into an existing URL?

    - by Mezelderz
    I am trying to auto add each word or words divided by comma into an existing url. I have url lets say http://stackoverflow.com/search?q=HERE IS THAT TEXT. I have this function: function movie_cast( $atts, $content = null ) { return '<div class="movie_cast">Cast: '.$content.'</div>'; } add_shortcode( 'movie_cast', 'movie_cast' ); I am using it: [movie_cast]Actor 1, Actor 2[/movie_cast] Output from this is just text: Actor 1, Actor 2 How can I get otput it like this: <a href="http://stackoverflow.com/search?q=Actor 1">Actor 1</a>, <a href="http://stackoverflow.com/search?q=Actor 2">Actor 2</a>

    Read the article

  • C++ Iterators and inheritance

    - by jomnis
    Have a quick question about what would be the best way to implement iterators in the following: Say I have a templated base class 'List' and two subclasses "ListImpl1" and "ListImpl2". The basic requirement of the base class is to be iterable i.e. I can do: for(List<T>::iterator it = list->begin(); it != list->end(); it++){ ... } I also want to allow iterator addition e.g.: for(List<T>::iterator it = list->begin()+5; it != list->end(); it++){ ... } So the problem is that the implementation of the iterator for ListImpl1 will be different to that for ListImpl2. I got around this by using a wrapper ListIterator containing a pointer to a ListIteratorImpl with subclasses ListIteratorImpl2 and ListIteratorImpl2, but it's all getting pretty messy, especially when you need to implement operator+ in the ListIterator. Any thoughts on a better design to get around these issues?

    Read the article

  • Quickest way to compute the number of shared elements between two vectors

    - by shn
    Suppose I have two vectors of the same size vector< pair<float, NodeDataID> > v1, v2; I want to compute how many elements from both v1 and v2 have the same NodeDataID. For example if v1 = {<3.7, 22>, <2.22, 64>, <1.9, 29>, <0.8, 7>}, and v2 = {<1.66, 7>, <0.03, 9>, <5.65, 64>, <4.9, 11>}, then I want to return 2 because there are two elements from v1 and v2 that share the same NodeDataIDs: 7 and 64. What is the quickest way to do that in C++ ? Just for information, note that the type NodeDataIDs is defined as I use boost as: typedef adjacency_list<setS, setS, undirectedS, NodeData, EdgeData> myGraph; typedef myGraph::vertex_descriptor NodeDataID; But it is not important since we can compare two NodeDataID using the operator == (that is, possible to do v1[i].second == v2[j].second)

    Read the article

  • What's the simplest way of defining lexicographic comparison for elements of a class?

    - by the_mandrill
    If I have a class that I want to be able to sort (ie support a less-than concept), and it has several data items such that I need to do lexicographic ordering then I need something like this: struct MyData { string surname; string forename; bool operator<(const MyData& other) const { return surname < other.surname || (surname==other.surname && forename < other.forename); } }; This becomes pretty unmanageable for anything with more than 2 data members. Are there any simpler ways of achieving it? The data members may be any Comparable class.

    Read the article

  • SQL Convert Nvarchar(255) to DateTime problem

    - by steven
    Hi, I'm using SQL server 2008. I have 2 Tables: Table 1 and Table 2. Table 1 has 1 column called: OldDate which is nvarchar(255), null Table 2 has 1 column called: NewDate which is datetime, not null Example data in Table 1: 26/07/03 NULL NULL 23/07/2003 7/26/2003 NULL 28/07/03 When i try CAST(OldDate as datetime) I get this error: Arithmetic overflow error converting expression to data type datetime. I need to insert OldDate into NewDate with no errors. I can't skip some rows. Anyhelp would be appreciated.

    Read the article

  • Is void *p = 0L valid?

    - by Artefacto
    In this answer, sassman initializes a pointer with: zend_class_entry* ce = 0L; My question is – is this valid? I would say it isn't, to initialize the variable with a null pointer either an unadorned (and possibly casted to void *) 0 constant, or some macro that evaluates to that such as NULL should be used. However, I can't find definitive language in the standard that supports this interpretation. All it says is: An integer constant expression with the value 0, or such an expression cast to type void *, is called a null pointer constant.

    Read the article

  • What do C# Table Adapters actually return?

    - by Raven Dreamer
    I'm working on an application that manipulates SQL tables in a windows form application. Up until now, I've only been using the pre-generated Fill queries, and self-made update and delete queries (which return nothing). I am interested in storing the value of a single value from a single column (an 'nchar(15)' name), and though I have easily written the SQL code to return that value to the application, I have no idea what it will be returned as. SELECT [Contact First Name] FROM ContactSkillSet WHERE [Contact ID] = @CurrentID Can the result be stored directly as a string? Do I need to cast it? Invoke a toString method?

    Read the article

  • C++ Reference of vector

    - by void
    Hello, class Refvect { public: vector<int> &refv; Refvect(int t, vector<int> &refv = vector<int>()) : refv(refv) { }; void operator()() { refv.clear(); } }; int main () { Refvect r(0); r(); } With Visual Studio 2010, this gives me an error : "vector iterators incompatible" at the execution, but I don't understand why (but I can insert elements in refv without any problem). The temporary object vector() lives as long as the reference, no?

    Read the article

  • error message fix

    - by user1722654
    for (int i = 0; i < dataGridView1.Rows.Count; i++) { //bool sleected = false; if (dataGridView1.Rows[i].Cells[3].Value != null) { selected.Add(i); } } //string donew = ""; // line off error textBox1.Text = ((String)dataGridView1.Rows[1].Cells[2].Value); /* for (int i = 0; i < selected.Count; i++) { textAdded.Add((String)dataGridView1.Rows[0].Cells[2].Value); // donew += (String)dataGridView1.Rows[selected[i]].Cells[2].Value; }*/ I keep getting the error Unable to cast object of type 'System.Double' to type 'System.String' What can I do to overcome this?

    Read the article

  • C++ How do you set an array of pointers to null in an initialiser list like way?

    - by boredjoe
    I am aware you cannot use an initialiser list for an array. However I have heard of ways that you can set an array of pointers to NULL in a way that is similar to an initialiser list. I am not certain how this is done. I have heard that a pointer is set to NULL by default, though I do not know if this is guaranteed/ in the C++ standard. I am also not sure if initialising through the new operator compared to normal allocation can make a difference too.

    Read the article

< Previous Page | 152 153 154 155 156 157 158 159 160 161 162 163  | Next Page >