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  • Python raises a KeyError (for an out of dictionary key) even though the key IS in the dictionary

    - by ignorantslut
    I'm getting a KeyError for an out of dictionary key, even though I know the key IS in fact in the dictionary. Any ideas as to what might be causing this? print G.keys() returns the following: ['24', '25', '20', '21', '22', '23', '1', '3', '2', '5', '4', '7', '6', '9', '8', '11', '10', '13', '12', '15', '14', '17', '16', '19', '18'] but when I try to access a value in the dictionary on the next line of code... for w in G[v]: #note that in this example, v = 17 I get the following error message: KeyError: 17 Any help, tips, or advice are all appreciated. Thanks.

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  • jUnit same exception in different cases

    - by coubeatczech
    Hi, I'm writing a jUnit test for a constructor that parses a String and then check numerous things. When there's wrong data, for every thing, some IllegalArgumentException with different message is thrown. So I would like to write tests for it, but how can i recognize what error was thrown? This is how can I do it: @Test(expected=IllegalArgumentException.class) public void testRodneCisloRok(){ new RodneCislo("891415",dopocitej("891415")); } and this is how I would like to be, but I don't know if it is possible to write it somehow: @Test(expected=IllegalArgumentException.class("error1")) public void testRodneCisloRok(){ new RodneCislo("891415",dopocitej("891415")); }

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  • Bash, Concatenating 2 strings to reference a 3rd variable

    - by Im Fine
    I have a bash script I am having some issues with concatenating 2 variables to call a 3rd. Here is a simplification of the script, but the syntax is eluding me after reading the docs. server_list_all="server1 server2 server3"; var1 = "server"; var2 = "all"; echo $(($var1_list_$var2)); This is about as close as I get to the right answer, it acknowledges the string and tosses an error on tokenization. syntax error in expression (error token is "server1 server2 server3.... Not really seeing anything in the docs for this, but it should be doable. EDIT: Cleaned up a bit

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  • Preserving NULL values in a Double Variable

    - by Sam
    Hi, I'm working on a vb.net application which imports from an Excel spreadsheet. If rdr.HasRows Then Do While rdr.Read() If rdr.GetValue(0).Equals(System.DBNull.Value) Then Return Nothing Else Return rdr.GetValue(0) End If Loop Else I was using string value to store the double values and when preparing the database statement I'd use this code: If (LastDayAverage = Nothing) Then command.Parameters.AddWithValue("@WF_LAST_DAY_TAG", System.DBNull.Value) Else command.Parameters.AddWithValue("@WF_LAST_DAY_TAG", Convert.ToDecimal(LastDayAverage)) End If I now have some data with quite a few decimal places and the data was put into the string variable in scientific notation, so this seems to be the wrong approach. It didn't seem right using the string variable to begin with. If I use a double or decimal type variable, the blank excel values come across as 0.0. How can I preserve the blank values? Thanks

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  • Assigning jQuery ajax response text to variable constanty returns null

    - by Dan Twining
    Hi all, hopefully one of you on this great site can help. I'm having issues with assigning a variable to a jQuery ajax call response text. I have a form which when submited runs my "checkemail" function to varify the email address can be found in a database. If it's found, the responseText == "true", else "false". This works fine, and can be seen ok using Firebug....but the actual variable the response text should be assigned to is constantly showing "", and therefore causing the function to return false all the time. function checkemail(){ var EmailFromForm = $("#lostemail").val(); var EmailCheckRes = $.ajax({ type : "POST", cache : false, url : "./scripts/passreset/emailcheck.php", data : "Email="+EmailFromForm, dataType : "text", }).responseText; if (EmailCheckRes == "true") { alert("Should say true: " + EmailCheckRes); return true; } else { $("#ErrorMsg").html("Your email address is either invalid or not found."); alert("Should say false: " + EmailCheckRes); return false; } } If anyone has any pointers as to what i'm doing wrong it'd be greatly appreciated.

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  • How to get reference of activity object ?

    - by Fevos
    Hi i want to show messageBox or notification when connection lost in Static DB class but i cant use getApplicationContext() becouse its a static class and i tried to call other class called notification but i have error so how i could pass activity object to my new class .

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  • Reference to fnc.

    - by atch
    Hi guys, Is there a way in java to do something like this: void fnc(void Reference_to_other_func()); What I'm trying is basically I have number of places where I need to display this same text to the user and the only difference is which method is invoked after this text. So for example instead of writing: System.out.println("Hello"); f1(); //in some other place System.out.println("Hello"); f2(); //etc I would like to define one function: public void f(void Reference_to_other_func()) { System.out.println("Hello"); Reference_to_other_func();//HERE I'M INVOKING } and then instead of repeating this whole code I could write something like this: f(f1); //in some other place f(f2) //etc. Thanks for answers

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  • pass by const reference of class

    - by small_potato
    void foo(const ClassName &name) { ... } How can I access the method of class instance name? name.method() didn't work. then I tried: void foo(const ClassName &name) { ClassName temp = name; ... .... } I can use temp.method, but after foo was executed, the original name screwed up, any idea? BTW, the member variable of name didn't screwed up, but it was the member variable of subclass of class screwed up.

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  • Pass reference to ArrayLists to a method.

    - by bhavna raghuvanshi
    here is the whole program: public class ListMerge { public static void main( String[] args) { Scanner input = new Scanner(System.in); System.out.println ("Input length of arraylist 1:"); int n = input.nextInt(); ArrayList x = new ArrayList(); ArrayList y = new ArrayList(); for (int i = 0; i < n; i++) { System.out.println ("Input x[ " + i +"] :" ); x.add(new Integer(i)); } System.out.println ("Input length of arraylist 2:"); int m = input.nextInt(); for (int i = 0; i < m; i++) { System.out.println ("Input y[ " + i +"] :" ); y.add(new Integer(i)); } } list int merge(ArrayList x, ArrayList y) { List all = new ArrayList(); all.addAll(x); all.addAll(y); System.out.println(all); return all; } } also tell me how do i call the function merge?

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  • Access a static variable by $var::$reference

    - by chuckg
    I am trying to access a static variable within a class by using a variable class name. I'm aware that in order to access a function within the class, you use call_user_func(): class foo { function bar() { echo 'hi'; } } $class = "foo"; all_user_func(array($class, 'bar')); // prints hi However, this does not work when trying to access a static variable within the class: class foo { public static $bar = 'hi'; } $class = "foo"; call_user_func(array($class, 'bar')); // nothing echo $foo::$bar; // invalid How do I get at this variable? Is it even possible? I have a bad feeling this is only available in PHP 5.3 going forward and I'm running PHP 5.2.6. Thanks.

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  • Patterns to deal with with functions that can have different kinds of results.

    - by KaptajnKold
    Suppose you have an method on an object that given the some input alters the objects state if the input validates according to some complex logic. Now suppose that when the input doesn't validate, it can be due to several different things, each of which we would like to be able to deal with in different ways. I'm sure many of you are thinking: That's what exceptions are for! I've thought of this also. But my reservation against using exceptions is that in some cases there is nothing exceptional about the input not validating and I really would like to avoid using exceptions to control what is really just in the expected flow of the program. If there were only one interpretation possible, I could simply choose to return a boolean value indicating whether or not the operation resulted in a state change or not and the respond appropriately when it did not. There is of course also the option to return a status code which the client can then choose to interpret or not. I don't like this much either because there is nothing semantic about status codes. The solution I have so far is to always check for each possible situation which I am able to handle before I call the method which then returns a boolean to inform the client if the object changed state. This leaves me the flexibility to handle as few or as many as the possible situations as I wish depending on the context I am in. It also has the benefit of making the method I am calling simpler to write. The drawback is that there is quite a lot of duplication in the client code wherever I call the method. Which of these solutions do you prefer and why? What other patterns do people use for providing meaningful feedback from functions? I know that some languages support multiple return values, and I if I had that option I would surely prefer it.

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  • Passing C string reference to C#

    - by user336109
    c code extern "C" __declspec(dllexport) int export(LPCTSTR inputFile, string &msg) { msg = "haha" } c# code [DllImport("libXmlEncDll.dll")] public static extern int XmlDecrypt(StringBuilder inputFile, ref Stringbuilder newMsg) } I got an error when I try to retrieve the content of newMsg saying that I'm trying to write to a protected memory area. What is the best way to retrieve the string from c to c#. Thanks.

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  • How to avoid circular reference when excel cell update

    - by Nimo
    Hi, I'm writing a set of functions in c++ which can be called by excel. However, these functions are asynchronous, therefore no immediate return values available. Once a result is available I used a callback function through VBA which update the result to the relevant cell which called the functions. But, here I'm having circular function calling problem, because when I update the cell. excel automatically call the original function once again. Please help me to get around this problem Thank You

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  • EF4 (CPT5) ForeignKeyAttribute in base class - Assert Failure entityType != null

    - by Anthony Johnston
    Getting an error when trying to set a ForeignKeyAttribute in a base class class User{} abstract class FruitBase{ [ForeignKey("CreateById")] public User CreateBy{ get; set; } public int CreateById{ get; set; } } class Banana{} class DataContext : DbContext{ DbSet<Banana> Bananas{ get; set; } } If I move the FruitBase code into the banana, all is well, but I don't want to, as there will be many many fruit and I want to remain relatively DRY if I can Is this a know issue that will be fixed by March? Does anyone know a work around?

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  • Prevent debugging projects that are added as reference in Visual Studio

    - by DSWD
    I have a project that is auto generated. This project is referenced by my web app in visual studio. When i step through the code in debug mode the code from this project gets stepped into. Is there a way I can skip this code in debug mode. I can't use System.Diagnostics.DebuggerStepThroughAttribute since the code will get replaced every time my datasource changes. Thanks,

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  • C++, is it possible to obtain the dimension of an array?

    - by aaa
    hi. Suppose I have some pointer, which I want to reinterpret as static dimension array reference: double *p; double (&r)[4] = ?(p); // some construct? // clarify template< size_t N> void function(double (&a)[N]); ... double *p; function(p); // this will not work. // I would like to cast p as to make it appear as double[N] Is it possible to do so? how do I do it?

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  • int vs const int&

    - by Valdo
    I've noticed that I usually use constant references as return values or arguments. I think the reason is that it works almost the same as using non-reference in the code. But it definitely takes more space and function declarations become longer. I'm OK with such code but I think some people my find it a bad programming style. What do you think? Is it worth writing const int& over int? I think it's optimized by the compiler anyway, so maybe I'm just wasting my time coding it, a?

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  • floating point exception in C++ code !

    - by mekasperasky
    #include<stdio.h> #include<math.h> int main () { FILE *fp; fp=fopen("output","w"); float t,y=0,x=0,e=5,f=1,w=1; for (t=0;t<10;t=t+0.01) { if( y==inf && y== nan) break; fprintf(fp,"%lf\t%lf\n",y,x); y = y + ((e*(1 - x*x)*y) - x + f*cos(w*t))*t; x = x + y*t; } return (0); } why is the ouput giving infinite and NAN values?

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  • Pointer-like behavior in Java

    - by Shmoo
    I got the following: class A{ int foo; } class B extends A{ public void bar(); } I got a instance of A and want to convert it to an instance of B without losing the reference to the variable foo. For example: A a = new A(); a.foo = 2; B b = a; <-- what I want to do. //use b b.foo = 3; //a.foo should now be 3 Thanks for any help!

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  • can function return 0 as reference

    - by helloWorld
    I have this snippet of the code Account& Company::findAccount(int id){ for(list<Account>::const_iterator i = listOfAccounts.begin(); i != listOfAccounts.end(); ++i){ if(i->nID == id){ return *i; } } return 0; } Is this right way to return 0 if I didn't find appropriate account? cause I receive an error: no match for 'operator!' in '!((Company*)this)->Company::findAccount(id)' I use it this way: if(!(findAccount(id))){ throw "hey"; } thanks in advance

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  • Postion of & to denote reference type

    - by Matt H
    I was wondering whether to put the ampersand (&) after the variable type or before the variable name. To put it simply, I want to know which one is the conventional style or the standard, or if it is entirely down to preference. int &x; or int& x;

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  • Why do I get a Null Pointer Exception?

    - by Roman
    I have this code: Manager manager = new Manager("Name"); MyWindowListener windowListener = new MyWindowListener(); manager.addWindowListener(windowListener); Eclipse writes that I have a NullPointerException in the last line. What can be the reason for that. I do have constructors in the Manager and MyWindowListener. If it's important MyWindowListener implements WindowListener.

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