c++

Extracting bool from istream in a templated function

I'm converting my fields class read functions into one template function. I have field classes for int, unsigned int, long, and unsigned long. These all use the same method for extracting a value from an istringstream (only the types change): template <typename Value_Type> Value_Type Extract_Value(const std::string& input_string) { ...

Real-time spectrum analyzer with API

I'm looking for a C or C++ API that will give me real-time spectrum analysis of a waveform on Windows. I'm not entirely sure how large a sample window it should need to determine frequency content, but the smaller the better. For example, if it can work with a 0.5 second long sample and determine frequency content to the Hz, that would...

Visitor and templated virtual methods

In a typical implementation of the Visitor pattern, the class must account for all variations (descendants) of the base class. There are many instances where the same method content in the visitor is applied to the different methods. A templated virtual method would be ideal in this case, but for now, this is not allowed. So, can te...

Linker error with Duplicated Symbols, SWIG and C++ Vectors

I came across this error trying to compile a shared object from 2 sets of objects. The first set contains one .os object compiled from one cpp file generated by SWIG. The second set is contains all of the .so files from the individual files that make up the interface to be wrapped. $g++ -shared *.os -o Mathlibmodule.so ld: duplicate...

gcc 4.5 installation problem under ubuntu

I tried to install gcc 4.5 on ubuntu 10.04 but failed. Here is a compile error that I don't know how to solve. Is there anyone successfully install the latest gcc on ubuntu? Following is my steps and the error message, I'd like to know where is the problem.... Step1: download these files: gcc-core-4.5.0.tar.gz gcc-g++-4.5.0.tar.gz gmp-...

C++ header files and variable scope

I want to organize my c++ variables and functions in the following way: function prototypes in a header file "stuff.h", function implementation in "stuff.cpp", then say #include "stuff.h" in main.cpp (so I can call functions implemented in stuff.cpp). So far so good. Now I want to declare some variables in stuff.cpp that have global s...

Creating rapid function overloads in C++

template<typename Functor, typename Return, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5, typename Arg6, typename Arg7, typename Arg8, typename Arg9, typename Arg10> class LambdaCall : public Instruction { public: LambdaCall(Functor func ...

pass a pointer of a class

Say I have Class1 and Class2 and I want a shallow copy constructor for Class1. Class1 has a member variable, which is a pointer pointing to a Class2 instance. Also I have to be able to change the Class2 ptr is pointing at. in header file: class Class1 { Class2* ptr; ... } in source file: Class1::Class1() { ptr = new Clas...

TrackMouseEvent not working

Basically I call TrackMouseEvent in my WM_CREATE then I call it again after a WM_MOUSELEAVE but this freezes up my program. Where should I be sticking it? Thanks ...

initializing a vector of custom class in c++

Hey basically Im trying to store a "solution" and create a vector of these. The problem I'm having is with initialization. Heres my class for reference class Solution { private: // boost::thread m_Thread; int itt_found; int dim; pfn_fitness f; double value; std::vector<double> x; public: ...

How to make multiple windows using Win32 API

I see plenty of tutorials and articles showing me how to make a simple windows program, which is great but none of them show me how to make multiple windows. Right now I have working code that creates and draws a layered window and I can blit stuff using GDI to draw anything I want on it, drag it around, even make it transparent, etc. ...

Should I use a global var or call the function every time? C++

Im using: bool GetOS(LPTSTR pszOS) { OSVERSIONINFOEX osve; BOOL bOsVersionInfoEx; ZeroMemory(&osve, sizeof(OSVERSIONINFOEX)); osve.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX); if( !(bOsVersionInfoEx = GetVersionEx ((OSVERSIONINFO *) &osve)) ) return false; TCHAR buf[80]; StringCchPrintf( buf, 80, TEXT("%...

C++ Why am I unable to use an enum declared globally outside of the class it was declared in?

Right now, my project has two classes and a main. Since the two classes inherit from each other, they are both using forward declarations. In the first object, right underneath the #include statement, I initialize two enums, before the class definition. I can use both enums just fine inside that class. However, if I try to use those enum...

Win32 C/C++ Load Image from memory buffer

I want to load a image (.bmp) file on a Win32 application, but I do not want to use the standard LoadBitmap/LoadImage from Windows API: I want it to load from a buffer that is already in memory. I can easily load a bitmap directly from file and print it on the screen, but this issue is making me stuck :( What I'm looking for is a functi...

Casting to derived type problem in C++

Hey there everyone, I am quite new to C++, but have worked with C# for years, however it is not helping me here! :) My problem: I have an Actor class which Ball and Peg both derive from on an objective-c iphone game I am working on. As I am testing for collision, I wish to set an instance of Ball and Peg appropriately depending on th...

inspect C++ template instantiation

hello. Is there some utility which would allow me to inspect template instantiation? my compiler is g++ or Intel. Specific points I would like: Step by step instantiation. Instantiation backtrace (can hack this by crashing compiler. Better method?) Inspection of template parameters. @gf helpd me with simple type printing, http://s...

Is there a C++ graphing library?

Is there a C++ graphing library that can display visual graphs (such as hyperbolas and parabolas and linear equations) based on the equation it is given and that is cross platform? Or am I just asking for too much... ...

What could possibly cause this error when declaring an object inside a class?

I'm battling with this assignment :) I've got two classes: Ocean and Grid. When I declare an object of the Grid inside the Ocean: unsigned int sharkCount; Grid grid; The compiler/complainer says: error C2146: syntax error : missing ';' before identifier 'grid' Can you possibly predict what produces this error with the limited i...

C++: looking for thread based a parallel kd tree library.

Hello, Are there some implementation for KD-Tree on shared memory machines? thanks Arman. ...

Lambda Expressions and Memory Management

How do the Lambda Expressions / Closures in C++0x complicate the memory management in C++? Why do some people say that closures have no place in languages with manual memory management? Is their claim valid and if yes, what are the reasons behind it? ...