What does the percent sign mean in PHP?
What exactly does this mean? $number = ( 3 - 2 + 7 ) % 7; ...
operators
Way of processing a string of plus and minus operations
Hello, I'm writing a java method that takes a string of plus and minus operations, eg "+1+2+3-5" and I want it to return an int of the answer. I'm trying to do this as efficiently as possible. I've tried the String.split() method, but it gets slightly confusing with the pluses and minuses. Can anyone help? No, this isn't homework. ...
C++ [] array operator with multiple arguments?
Can I define in C++ an array operator that takes multiple arguments? I tried it like this: const T& operator[](const int i, const int j, const int k) const{ return m_cells[k*m_resSqr+j*m_res+i]; } T& operator[](const int i, const int j, const int k){ return m_cells[k*m_resSqr+j*m_res+i]; } But I'm getting this error: error C28...
What does the '&' operator do in C++?
n00b question. I am a C guy and I'm trying to understand some C++ code. I have the following function declaration: int foo(const string &myname) { cout << "called foo for: " << myname << endl; return 0; } How does the function signature differ from the equivalent C: int foo(const char *myname) Is there a difference between usin...
prolog syntax problem
I can't distinguish these symbols: = and =:= \= and =\= [X,Y] and [X|Y] What’s the difference ? ...
Why is g++ saying 'no match for ‘operator=’ when there clearly is, and Visual Studio can see that there is?
I'm writing an interface library that allows access to variables within tables (up to a theoretically infinite depth) in an object of type regula::State. I'm accomplishing this by overloading operator[] within a class, which then returns another of that same class, and calls operator[] again as needed. For example: regula::State t; t["m...
C# Operator Overloading post-fix increment
I'm coding a date class and am having trouble with the post-fix increment (the prefix increment seems fine). Here is the sample code: public class date { int year, month, day; public date(int d, int m, int y) { day = d; month = m; year = y; } static public date operator ++(d...
operator << in c#
i couldn't understand this code in c# int i=4 int[] s =new int [1<<i]; Console.WriteLine(s.length); the ouput is 16 i don't know why the output like that? ...
problem while using enum for operators like +, - in c
Hi, I'm trying to enumerate some operators, my code line is : enum operations{+=4,-,%,<,>} when i'm trying to compile this line , gcc says : expected identifier before ‘+’ token So, how can I enumerate these operators. Can we use some escape characters for them ? ...
Understanding Incrementing
For example this: var a = 123; var b = a++; now a contains 124 and b contains 123 I understand that b is taking the value of a and then a is being incremented. However, I don't understand why this is so. The principal reason for why the creators of JavaScript would want this. Is this really more useful than doing it the PHP way? What...
Member access differences.
can someone tell me what is the different between (*ptr).field and ptr->field? I know it connect somehow to static and dynamic linking, but i dont know what is it. can someone tell me the differnet and give me an example? edit: if i have this code: Point p; //point is a class that derive from class shape Shape *s=&p; ...
explicit conversion operator error when converting generic lists
I am creating an explicit conversion operator to convert between a generic list of entity types to a generic list of model types. Does anyone know why I get the following error: User-defined conversion must convert to or from the enclosing type I already have an explicit conversion operator between Entity.objA and Model.objA which...
PHP's Dot Equals `.=` operator in Javascript?
How can you use PHP's Dot Equals .= operator in Javascript? ...
What does the ^ operator do in Java?
What function does the "^" operator serve in Java? When I try this: int a = 5^n; ...it gives me: for n = 5, returns 0 for n = 4, returns 1 for n = 6, returns 3 ...so I guess it doesn't indicate exponentiation. But what is it then? ...
Question about C programming
int a, b; a = 1; a = a + a++; a = 1; b = a + a++; printf("%d %d, a, b); output : 3,2 What's the difference between line 3 and 5? ...
Matlab Unused input notation details
Matlab R2009b introduced a new "operator" - ~ - to symbolize an unused function output or input. I have detailed question about that implementation. (Calling all @Loren s.) What does the function see for the value of an unused input parameter? i.e. if my function is defined as myfunc(argOne, argTwo, argThree) and it’s called like...
Arithmetic operator confusion
Why I'm getting two different values while using the arithmetic operators for the same value of variables. I've just altered little bit my second program, which is resulted in giving me the different output. Could anyone please tell me why? int number=113; int rot=0; rot=number%10; rot*=100+number/10; System.out.println(rot);//3...
What does the operator "<<" mean in C#?
I was doing some basic audio programming in C# using the NAudio package and I came across the following expression and I have no idea what it means, as i've never seen the << operator being used before. So what does << mean? Please give a quick explaination of this expression. short sample = (short)((buffer[index + 1] << 8) | buffer[in...
Double Buffering for Game objects, what's a nice clean generic C++ way?
This is in C++. So, I'm starting from scratch writing a game engine for fun and learning from the ground up. One of the ideas I want to implement is to have game object state (a struct) be double-buffered. For instance, I can have subsystems updating the new game object data while a render thread is rendering from the old data by guar...
Why does "x ^= true" produce false in this example?
Hi, Why does the statement z ^= true produce a false when the previous produces a true ? bool v = true; bool z = false; z ^= v; Console.WriteLine(z); z ^= true; Console.WriteLine(z); OUTPUT ====== True False ...