Search Results

Search found 61651 results on 2467 pages for 'function object'.

Page 304/2467 | < Previous Page | 300 301 302 303 304 305 306 307 308 309 310 311  | Next Page >

  • Retruning reference to object not changing the address in c++

    - by ashish-sangwan
    I am trying to understand function returning reference. For that i have written a simple program :- include using namespace std; class test { int i; friend test& func(); public: test(int j){i=j;} void show(){cout< }; test& func() { test temp(10); return temp; //// Address of temp=0xbfcb2874 } int main() { test obj1(50); // Address of obj1=0xbfcb28a0 func()=obj1; <= Problem:The address of obj1 is not changing obj1.show(); // // Address of obj1=0xbfcb28a0 return 0; } I run the program using gdb and observed that the address of obj1 still remains same but i expect it to get changed to 0xbfcb2874. I am not clear with the concept. Please help. Thanks in advance

    Read the article

  • Appending a function to an existing onclick event at page load

    - by tonsils
    Hi, I have the following html code that is pre written by the app I am using, which I do not have access to, i.e. <td align="center" class="shuttleControl"> <img src="/i/mydb/icons/shuttle_reload.png" onclick="g_Shuttlep_v61.reset();" alt="Reset" title="Reset"/> <img src="/i/mydb/icons/shuttle_last.png" onclick="g_Shuttlep_v61.move_all();" alt="Move All" title="Move All"/> <img src="/i/mydb/icons/shuttle_right.png" onclick="g_Shuttlep_v61.move();" alt="Move" title="Move" /> <img src="/i/mydb/icons/shuttle_left.png" onclick="g_Shuttlep_v61.remove();" alt="Remove" title="Remove" /> <img src="/i/mydb/icons/shuttle_first.png" onclick="g_Shuttlep_v61.remove_all();" alt="Remove All" title="Remove All" /> </td> Based on the above code, using jQuery, would it be possible that when the page finishes loading, search for the img src "shuttle_last.png" and append to it's onclick call, my own function get_Count(); ? That is, I would then see the following code when I do a view page source for this particular line, i.e.: <img src="/i/mydb/icons/shuttle_last.png" onclick="g_Shuttlep_v61.move_all();get_Count();" alt="Move All" title="Move All"/> Is this possible - if so, would really appreciate a code sample? Thanks.

    Read the article

  • Elegant code question: How to avoid creating unneeded object

    - by SeaDrive
    The root of my question is that the C# compiler is too smart. It detects a path via which an object could be undefined, so demands that I fill it. In the code, I look at the tables in a DataSet to see if there is one that I want. If not, I create a new one. I know that dtOut will always be assigned a value, but the the compiler is not happy unless it's assigned a value when declared. This is inelegant. How do I rewrite this in a more elegant way? System.Data.DataTable dtOut = new System.Data.DataTable(); . . // find table with tablename = grp // if none, create new table bool bTableFound = false; foreach (System.Data.DataTable d1 in dsOut.Tables) { string d1_name = d1.TableName; if (d1_name.Equals(grp)) { dtOut = d1; bTableFound = true; break; } } if (!bTableFound) dtOut = RptTable(grp);

    Read the article

  • Iterating over member typed collection fails when using untyped reference to generic object

    - by Alexander Pavlov
    Could someone clarify why iterate1() is not accepted by compiler (Java 1.6)? I do not see why iterate2() and iterate3() are much better. This paragraph is added to avoid silly "Your post does not have much context to explain the code sections; please explain your scenario more clearly." protection. import java.util.Collection; import java.util.HashSet; public class Test<T> { public Collection<String> getCollection() { return new HashSet<String>(); } public void iterate1(Test test) { for (String s : test.getCollection()) { // ... } } public void iterate2(Test test) { Collection<String> c = test.getCollection(); for (String s : c) { // ... } } public void iterate3(Test<?> test) { for (String s : test.getCollection()) { // ... } } } Compiler output: $ javac Test.java Test.java:11: incompatible types found : java.lang.Object required: java.lang.String for (String s : test.getCollection()) { ^ Note: Test.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details. 1 error

    Read the article

  • C# function called after dependency property have been set

    - by mizipzor
    My code currently looks like this: private Foo myFoo; public Foo CurrentFoo { get { return myFoo; } set { SetFoo(value); } } private void SetFoo(Foo newFoo) { // Do stuff // Here be dragons myFoo = newFoo; } To be able to bind it in XAML/WPF I need to turn Foo into a dependency property: public static DependencyProperty CurrentFooProperty = DependencyProperty.Register("CurrentFoo", typeof(Foo), typeof(FooHandler), new PropertyMetadata(false)); public Foo CurrentFoo { get { return (Foo)GetValue(CurrentFooProperty); } set { SetValue(CurrentFooProperty, value); } } Ive heard that you shouldnt do magic inside the actual C# property set {}, since it might not be called but the value is written directly to the dependency property. If this is false, let me know, it seems like the most obvious and simple route to take. I know I can add a validation function to the dependency property but I assume that it shouldnt be used for this? I need to communicate the change to legacy systems that cannot yet be bound in XAML. Whats the best way to approach this problem?

    Read the article

  • Matlab fft function

    - by CTZStef
    The code below is from the Matlab 2011a help about fft function. I think there is a problem here : why do they multiply t(1:50) by Fs, and then say it's time in millisecond ? Certainly, it happens to be true in this very particular case, but change the value of Fs to, say, 2000, and it won't work anymore, obviously because of this factor of 2. Right ? Quite misleading, isn't it ? What do I miss ? Fs = 1000; % Sampling frequency T = 1/Fs; % Sample time L = 1000; % Length of signal t = (0:L-1)*T; % Time vector % Sum of a 50 Hz sinusoid and a 120 Hz sinusoid x = 0.7*sin(2*pi*50*t) + sin(2*pi*120*t); y = x + 2*randn(size(t)); % Sinusoids plus noise plot(Fs*t(1:50),y(1:50)) title('Signal Corrupted with Zero-Mean Random Noise') xlabel('time (milliseconds)') Clearer with this : fs = 2000; % Sampling frequency T = 1 / fs; % Sample time L = 1000; % Length of signal t2 = (0:L-1)*T; % Time vector f = 50; % signal frequency s2 = sin(2*pi*f*t2); figure, plot(fs*t2(1:50),s2(1:50)); % NOT good figure, plot(t2(1:50),s2(1:50)); % good

    Read the article

  • F# ref-mutable vars vs object fields

    - by rwallace
    I'm writing a parser in F#, and it needs to be as fast as possible (I'm hoping to parse a 100 MB file in less than a minute). As normal, it uses mutable variables to store the next available character and the next available token (i.e. both the lexer and the parser proper use one unit of lookahead). My current partial implementation uses local variables for these. Since closure variables can't be mutable (anyone know the reason for this?) I've declared them as ref: let rec read file includepath = let c = ref ' ' let k = ref NONE let sb = new StringBuilder() use stream = File.OpenText file let readc() = c := stream.Read() |> char // etc I assume this has some overhead (not much, I know, but I'm trying for maximum speed here), and it's a little inelegant. The most obvious alternative would be to create a parser class object and have the mutable variables be fields in it. Does anyone know which is likely to be faster? Is there any consensus on which is considered better/more idiomatic style? Is there another option I'm missing?

    Read the article

  • tiemout for a function that waits indefiinitely (like listen())

    - by Fantastic Fourier
    Hello, I'm not quite sure if it's possible to do what I'm about to ask so I thought I'd ask. I have a multi-threaded program where threads share a memory block to communicate necessary information. One of the information is termination of threads where threads constantly check for this value and when the value is changed, they know it's time for pthread_exit(). One of the threads contains listen() function and it seems to wait indefinitely. This can be problematic if there are nobody who wants to make connection and the thread needs to exit but it can't check the value whether thread needs to terminate or not since it's stuck on listen() and can't move beyond. while(1) { listen(); ... if(value == 1) pthread_exit(NULL); } My logic is something like that if it helps illustrate my point better. What I thought would solve the problem is to allow listen() to wait for a duration of time and if nothing happens, it moves on to next statement. Unfortunately, none of two args of listen() involves time limit. I'm not even sure if I'm going about the right way with multi-threaded programming, I'm not much experienced at all. So is this a good approach? Perhaps there is a better way to go about it? Thanks for any insightful comments.

    Read the article

  • How to face observable object containing an observable field

    - by iseek
    Hello, I need a hint concerning MVC and Observer-Pattern. For example a model contains the classes "Address" and "Person". The Address class contains the fields street:String, zipcode:String, location:String. Whereas the Person class contains the fields name:String, firstName:String, address:Address. My approach so far looks something like this: Both, Address and Person are observable. If one of their setters is being called, I validate whether the current value and new value differ. Only in this case an update event is fired. The event contains the source, the name of the changed field, the old and the new value. The class for the view contains text fields to display and edit the information of a person: name, firstname, street, zipcode, location. It knows the Person model and is an subscribed observer for the person. So it gets the update events from the person object. My questions concerns the address field from type Address in the person class, since an address is observable on its own. If the view gets an update event from person when a new address has been set, I can update all of the address related fields in the view. But what if a field of the address changes? Should the view also register for update events from the address? Any hints about common design approaches would be appreciated. Greetings.

    Read the article

  • Dropdown list bound to object data source - how to update on a button click

    - by Jen
    This is probably something really stupidly simple.. I have a drop down list bound to an object data source. I have set AppendDataBoundItems to true so that I can have an initial select. <asp:DropDownList ID="Accommodations1" runat="server" AutoPostBack="true" DataTextField="AccommodationTypeDescription" DataValueField="Id" OnDataBound="Accommodations1_DataBound" onSelectedIndexChanged="Accommodations1_SelectedIndexChanged" Width="200px" DataSourceID="AccommodationDs" AppendDataBoundItems="true"> <asp:ListItem Text="Select" Value=""></asp:ListItem> </asp:DropDownList> <asp:ObjectDataSource ID="AccommodationDs" runat="server" OldValuesParameterFormatString="original_{0}" SelectMethod="ListByPropertyId" TypeName="PropertyAccommodationController"> <SelectParameters> <asp:Parameter Name="PropertyId" Type="Int32" /> </SelectParameters> </asp:ObjectDataSource> I have a button which adds an accommodaton - so after that happens I need the dropdown list to update to include the new accommodation. So I've tried calling databind on the dropdownlist, and databind on the datasource - and nothing is making this dropdown list update. eg. PropertyAccommodations1.DataBind(); Could someone please let me know what I'm doing wrong. Originally I thought it was due to an update panel issue.. but I've removed the update panel and it still doesn't work (and checked the master page doesn't include an update panel). Thanks!!

    Read the article

  • object.valid? returns false but object.errors.full_messages is empty

    - by user549563
    Hello I'm confuse about objects that I can't save, simplified model is class Subscription < ActiveRecord::base belongs_to :user, :class_name => "User", :foreign_key => "user_id" has_many :transactions, :class_name => "SubscriptionTransaction" validates_presence_of :first_name, :message => "ne peut être vide" validates_presence_of :last_name, :message => "ne peut être vide" validates_presence_of :card_number, :message => "ne peut être vide" validates_presence_of :card_verification, :message => "ne peut être vide" validates_presence_of :card_type, :message => "ne peut être vide" validates_presence_of :card_expires_on, :message => "ne peut être vide" attr_accessor :card_number, :card_verification validate_on_create :validate_card def validate_card unless credit_card.valid? credit_card.errors.full_messages.each do |message| errors.add_to_base message end end end def credit_card @credit_card ||= ActiveMerchant::Billing::CreditCard.new( :type => card_type, :number => card_number, :verification_value => card_verification, :month => card_expires_on.month, :year => card_expires_on.year, :first_name => first_name, :last_name => last_name ) end end and in my subscription_controller if subscription.save # do something else debugger # means breakpoint where i try subscription.errors.full_messages # do something else end I tried to use ruby-debug for this adding a breakpoint before. And subscription.valid? return false which explains that ActiveRecord doesn't allow the save method. Unfortunately i can't know why the object is invalid. subscription.errors.full_messages # => [] I'm stucked, if you have any idea, thank you.

    Read the article

  • TypeError: Object #<HTMLDocument> has no method 'observe' issue with the plugin chosen

    - by NewBoy
    Hi made attempts to install the Jquery plugin chosen which enables me to customise my <select> tag in all browsers. Click here Anyway i have integrated this pluigin into my site and i have come across the following error message in my element inspector..Click here "TypeError: Object # has no method 'observe'" from the following code <script type="text/javascript"> document.observe('dom:loaded', function(evt) { var select, selects, _i, _len, _results; if (Prototype.Browser.IE && (Prototype.BrowserFeatures['Version'] === 6 || Prototype.BrowserFeatures['Version'] === 7)) { return; } selects = $$(".chzn-select"); _results = []; for (_i = 0, _len = selects.length; _i < _len; _i++) { select = selects[_i]; _results.push(new Chosen(select)); } deselects = $$(".chzn-select-deselect"); for (_i = 0, _len = deselects.length; _i < _len; _i++) { select = deselects[_i]; _results.push(new Chosen(select,{allow_single_deselect:true})); } return _results; }); </script> Does anyone know how i can solve this problem??

    Read the article

  • Nhibernate Fluent domain Object with Id(x => x.id).GeneratedBy.Assigned not saveable

    - by urpcor
    Hi there, I am using for some legacy db the corresponding domainclasses with mappings. Now the Ids of the entities are calculated by some stored Procedure in the DB which gives back the Id for the new row.(Its legacy, I cant change this) Now I create the new entity , set the Id and Call Save. But nothing happens. no exeption. Even NH Profiler does not say a bit. its as the Save call does nothing. I expect that NH thinks that the record is already in the db because its got an Id already. But I am using Id(x = x.id).GeneratedBy.Assigned() and intetionally the Session.Save(object) method. I am confused. I saw so many samples there it worked. does any body have any ideas about it? public class Appendix { public virtual int id { get; set; } public virtual AppendixHierarchy AppendixHierachy { get; set; } public virtual byte[] appendix { get; set; } } public class AppendixMap : ClassMap<Appendix> { public AppendixMap () { WithTable("appendix"); Id(x => x.id).GeneratedBy.Assigned(); References(x => x.AppendixHierachy).ColumnName("appendixHierarchyId"); Map(x => x.appendix); } }

    Read the article

  • What's the SQL function for timestamp manipulation?

    - by Eric Leroy
    I'm new to SQL and the time functions are different than mySQL so I'm having a terrible time finding a good site reference with USEFUL timestamp queries. I'm not able to locate the correct way of doing this query in SQL: Id Timestamp ----------------------------------- 1145744 2012-10-10 18:15:11.500 1145743 2012-10-10 18:15:11.313 1145742 2012-10-10 18:15:11.313 1145741 2012-10-10 18:15:11.253 1145740 2012-10-10 18:15:11.190 1145739 2012-10-10 18:15:11.190 1145738 2012-10-10 18:15:11.127 1145737 2012-10-10 18:15:11.067 1145736 2012-10-10 18:15:11.063 1145735 2012-10-10 18:15:10.940 1145734 2012-10-10 18:15:10.817 SELECT * from table WHERE Timestamp ... RANGE I need the range of 2 timestamps so I can select rows by the following parameters: second range minute range hour range day range week range month range year range Is there one function to put in 2 timestamps and get the range? or is this a mix of functions I need? Any good site references would be greatly appriceated. MSDN site isn't helping me isolate the proper way of doing this. I've been searching for about an hour trying to get the last day from 1:30PM to 1:30PM today.

    Read the article

  • Pass arguments to a parameter class object

    - by David R
    This is undoubtedly a simple question. I used to do this before, but it's been around 10 years since I worked in C++ so I can't remember properly and I can't get a simple constructor call working. The idea is that instead of parsing the args in main, main would create an object specifically designed to parse the arguments and return them as required. So: Parameters params = new Parameters(argc, argv) then I can call things like params.getfile() Only problem is I'm getting a complier error in Visual Studio 2008 and I'm sure this is simple, but I think my mind is just too rusty. What I've got so far is really basic: In the main: #include "stdafx.h" #include "Parameters.h" int _tmain(int argc, _TCHAR* argv[]) { Parameters params = new Parameters(argc, argv); return 0; } Then in the Parameters header: #pragma once class Parameters { public: Parameters(int, _TCHAR*[]); ~Parameters(void); }; Finally in the Parameters class: include "Stdafx.h" #include "Parameters.h" Parameters::Parameters(int argc, _TCHAR* argv[]) { } Parameters::~Parameters(void) { } I would appreciate if anyone could see where my ageing mind has missed the really obvious. Thanks in advance.

    Read the article

  • Google App Engine error Object Manager has been closed

    - by newbie
    I had following error from Google App Engine when I was trying to iterate list in JSP page with EL. Object Manager has been closed I solved problem with following coe, but I don't think that it is very good solution to this problem: public List<Item> getItems() { PersistenceManager pm = getPersistenceManager(); Query query = pm.newQuery("select from " + Item.class.getName()); List<Item> items = (List<Items>) query.execute(); List<Item> items2 = new ArrayList<Item>(); // This line solved my problem Collections.copy(items, items2); // and this also pm.close(); return (List<Item>) items; } When I tried to use pm.detachCopyAll(items) it gave same error. I understood that detachCopyAll() method should do same what I did, but that method should be part of data nucelus, so it should be used instead of my owm methods. So why dosen't detachCopyAll() work at all?

    Read the article

  • WPF bound object update notification

    - by Carlo
    I have a TreeView with a few objects bound to it, let's say something like this: public class House { public List<Room> Rooms { get; set; } public List<Person> People { get; set; } public House() { this.Rooms = new List<Room>(); this.People = new List<Person>(); } public void BuildRoom(string name) { this.Rooms.Add(new Room() { Name = name }); } public void DestroyRoom(string name) { this.Rooms.Remove(new Room() { Name = name }); } public void PersonEnter(string name) { this.People.Add(new Person() { Name = name }); } public void PersonLeave(string name) { this.People.Remove(new Person() { Name = name }); } } public class Room { public string Name { get; set; } } public class Person { public string Name { get; set; } } The TreeView is watching over the House object, whenever a room is built / destroyed or a person enters / leaves, my tree view updates itself to show the new state of the house (I omitted some implementation details for simplicity). What I want is to know the exact moment when this update finishes, so I can do something right there, the thing is that I created an indicator of the selected item, and when something moves, I need to update said indicator's position, that's the reason I need it exactly when the tree view updates. Let me know if you know a solution to this. Also, the code is not perfect (DestroyRoom and PersonLeave), but you get the idea. Thanks!

    Read the article

  • Typedef equivalence in function arguments

    - by Warren Seine
    Hi guys, The question is kind of hard to ask without an example so here it is: #include <vector> struct O { }; struct C { template <typename T> void function1(void (C::*callback)(const O*)); template <typename T> void function2(void (C::*callback)(const typename T::value_type)); void print(const O*); }; int main() { C c; c.function1< std::vector<O*> >(&C::print); // Success. c.function2< std::vector<O*> >(&C::print); // Fail. } The error that I am given is: error: no matching function for call to ‘C::function2(void (C::*)(const O*))’. Basically, the only difference between calls is that in function2, I'm more generic since I use the typedef std::vector<O*>::value_type which should resolve to O*, hence similar to function1. I'm using G++ 4.2.1 (I know it's old), but Comeau confirms I'm wrong. Why does the compilation fail?

    Read the article

  • Using Generics to return a literal string or from Dictionary<string, object>

    - by Mike
    I think I outsmarted myself this time. Feel free to edit the title also I could not think of a good one. I am reading from a file and then in that file will be a string because its like an xml file. But in the file will be a literal value or a "command" to get the value from the workContainer so <Email>[email protected]</Email> or <Email>[? MyEmail ?]</Email> What I wanted to do instead of writing ifs all over the place to put it in a generic function so logic is If Container command grab from container else grab string and convert to desired type Its up to the user to ensure the file is ok and the type is correct so another example is so <Answer>3</Answer> or <Answer>[? NumberOfSales ?]</Answer> This is the procedure I started to work on public class WorkContainer:Dictionary<string, object> { public T GetKeyValue<T>(string Parameter) { if (Parameter.StartsWith("[? ")) { string key = Parameter.Replace("[? ", "").Replace(" ?]", ""); if (this.ContainsKey(key)) { return (T)this[key]; } else { // may throw error for value types return default(T); } } else { // Does not Compile if (typeof(T) is string) { return Parameter } // OR return (T)Parameter } } } The Call would be mail.To = container.GetKeyValue<string>("[email protected]"); or mail.To = container.GetKeyValue<string>("[? MyEmail ?]"); int answer = container.GetKeyValue<int>("3"); or answer = container.GetKeyValue<int>("[? NumberOfSales ?]"); But it does not compile?

    Read the article

  • function working fine in IE but the same funtion is not working for mozilla 3.6

    - by anand-juventus
    function VisibleDiv(obj) { if (obj == BaseLog) { var objStyle = document.getElementById('DivCalls').style; if (objStyle.display == "block") objStyle.display = "none"; else objStyle.display = "block"; } else if (obj == ViewReports) { var objStyle = document.getElementById('DivReports').style; if (objStyle.display == "block") objStyle.display = "none"; else objStyle.display = "block"; } else if (obj ==Management) { var objStyle = document.getElementById('DivManage').style; if (objStyle.display == "block") objStyle.display = "none"; else objStyle.display = "block"; } <a href="#" id="BaseLog" class="TextHeader" onclick="VisibleDiv(this)">Base Log </a> in the above code is working in IE but not working in mozilla 3.6. I have checked that obj==BaseLog is not working in the above code. I have tried many options like event.srcelement window.event.srcelement but all in vain. when I debug the code ,I found that obj is having complete value for IE but the same obj is having all the names .ie. the name of tag,id and class for "Base Log" seperated by #. i.e a#BaseLog#TextHeader# Please suggest what shoud I do?

    Read the article

  • Android: sending xml as document object, POST method

    - by juro
    i am new at programming and i need some help with that please =/ web service is already written but not by me. so all i have to do is send xml as document object by post method through web service. my code: public class send extends application { @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); HttpClient httpclient = new DefaultHttpClient(); HttpPost httppost = new HttpPost("http://app.local/test/"); try { DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance(); DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder(); Document document = documentBuilder.newDocument(); Element rootElement = document.createElement("packet"); rootElement.setAttribute("version", "1.2"); document.appendChild(rootElement); Element em = document.createElement("imei"); em.appendChild(document.createTextNode("000000000000000")); rootElement.appendChild(em); em = document.createElement("username"); em.appendChild(document.createTextNode("5555")); rootElement.appendChild(em); HttpResponse response = httpclient.execute(httppost); } catch (Exception e) { System.out.println("XML Pasing Excpetion = " + e); } } }

    Read the article

  • javascript array/object issue

    - by FlyingCat
    I am trying to push elements to an array. for (a=0; a < test.length; a++){ if(this.testnumber != test[a].number){ //it will only loop 8 times under conditional statement group = { title: test.Title , ID: test.ID, contents: [] }; this.company.push(group); this.testnumber = test.number[a]; } //outside of if conditional statement.. it will loop 15 times //i want every test[a].conetents get pushed to group.contents array. //this.company is the final variable I need for this function... group.contents.push(test[a].contents); } However, when I do console.log(this.company); I see 8 elmements with only 1 element in each group.contents array The ideal situation is to have 8 elements with 2 to 3 elements in the group.contents array I hope I explain my situation well. Any idea how to solve my issue? Thanks a lot!

    Read the article

  • Changing type of object in a conditional

    - by David Doria
    I'm having a bit of trouble with dynamic_casting. I need to determine at runtime the type of an object. Here is a demo: include include class PersonClass { public: std::string Name; virtual void test(){}; //it is annoying that this has to be here... }; class LawyerClass : public PersonClass { public: void GoToCourt(){}; }; class DoctorClass : public PersonClass { public: void GoToSurgery(){}; }; int main(int argc, char *argv[]) { PersonClass* person = new PersonClass; if(true) { person = dynamic_cast(person); } else { person = dynamic_cast(person); } person-GoToCourt(); return 0; } I would like to do the above. The only legal way I found to do it is to define all of the objects before hand: PersonClass* person = new PersonClass; LawyerClass* lawyer; DoctorClass* doctor; if(true) { lawyer = dynamic_cast(person); } else { doctor = dynamic_cast(person); } if(true) { lawyer-GoToCourt(); } The main problem with this (besides having to define a bunch of objects that won't be use) is that I have to change the name of the 'person' variable. Is there a better way? (I am not allowed to change any of the classes (Person, Lawyer, or Doctor) because they are part of a library that people who will use my code have and won't want to change). Thanks, Dave

    Read the article

  • Time complexity of a powerset generating function

    - by Lirik
    I'm trying to figure out the time complexity of a function that I wrote (it generates a power set for a given string): public static HashSet<string> GeneratePowerSet(string input) { HashSet<string> powerSet = new HashSet<string>(); if (string.IsNullOrEmpty(input)) return powerSet; int powSetSize = (int)Math.Pow(2.0, (double)input.Length); // Start at 1 to skip the empty string case for (int i = 1; i < powSetSize; i++) { string str = Convert.ToString(i, 2); string pset = str; for (int k = str.Length; k < input.Length; k++) { pset = "0" + pset; } string set = string.Empty; for (int j = 0; j < pset.Length; j++) { if (pset[j] == '1') { set = string.Concat(set, input[j].ToString()); } } powerSet.Add(set); } return powerSet; } So my attempt is this: let the size of the input string be n in the outer for loop, must iterate 2^n times (because the set size is 2^n). in the inner for loop, we must iterate 2*n times (at worst). 1. So Big-O would be O((2^n)*n) (since we drop the constant 2)... is that correct? And n*(2^n) is worse than n^2. if n = 4 then (4*(2^4)) = 64 (4^2) = 16 if n = 100 then (10*(2^10)) = 10240 (10^2) = 100 2. Is there a faster way to generate a power set, or is this about optimal?

    Read the article

  • Map Literals to Object Properties/Values

    - by vijay
    For eg, my input XML is look like this. <root> <myelemt> <input type="variable"> <variable>STARTDATE</variable> <variable>CUSTOMERNAME</variable> </input> </myelemt> </root> it is deserialized and loaded into the object MyXmlElemtObj in my code i have written like this, if(MyXmlElemtObj.input.variable.ToUpper() == "STARTDATE") ProcessObjectB(ObjectA.OrderDate); if(MyXmlElemtObj.input.variable.ToUpper() == "CUSTOMERNAME") ProcessObjectB(ObjectC.UserName); Here I am mapping those input literals to some objects value. The one thing that scares me is seeing some ** hard-coded literals** all over my code. Instead i would like to write something like ProcessObjectB(Common.GetMappedvalue(MyXmlElemtObj.input.variable)); Is there a way to isolate this mapping thing to common class, where i will predefine which literal is mapped to which values. The problem is the values are of objects created at the run time. If my question is making sense then So how do i achieve this? I think i have given all the necessary details. if anything is missing please metnion. Thx Much.

    Read the article

< Previous Page | 300 301 302 303 304 305 306 307 308 309 310 311  | Next Page >