Sometimes it is useful to use the starting address of an std::vector and temporarily treat that address as the address of a regularly allocated buffer. For instance replace this: char* buf = new char[size]; fillTheBuffer(buf, size); useTheBuffer(buf, size); delete[] buf; With This: vector<char> buf(size); fillTheBuffer(&buf[0],...
According to C++ standard (3.7.3.2/4) using (not only dereferencing, but also copying, casting, whatever else) an invalid pointer is undefined behavior (in case of doubt also see this question). Now the typical code to traverse an STL containter looks like this: std::vector<int> toTraverse; //populate the vector for( std::vector<int>::i...
Hi, Is some one able to explain why header files have something like this? class foo; // This here? class bar { bar(); }; Do you need an include statement when using this? Thanks. ...
I'm working with iterators on C++ and I'm having some trouble here. It says "Debug Assertion Failed" on expression (this->_Has_container()) on line interIterator++. Distance list is a vector< vector< DistanceNode > >. What I'm I doing wrong? vector< vector<DistanceNode> >::iterator externIterator = distanceList.begin(); while (exter...
template <class T> void max (T &a ,T &b) {}//generic template #1 template<> void max(char &c, char &d) {} //template specializtion #2 void max (char &c, char &d) {}//ordinary function #3 what is difference between 1 ,2, and 3? ...
I have a file containing data as follows 10 20 30 40 70 20 30 70 30 40 10 20 29 70 80 90 20 30 40 40 45 65 10 20 80 45 65 20 I want to remove all subset transaction from this file. output file should be like follows 10 20 30 40 70 29 70 80 90 20 30 40 40 45 65 10 20 80 Where records like 20 30 70 30 40 10 20 45 65 20 are rem...
Hello, I'm using DCMTK library for reading Dicom files (Image format used in medical image processing.) I'm having a problem in compiling this DCMTK source code. DCMTK uses some additional external libraries (zlib, tiff, libpng, libxml2, libiconv). I know that all libraries should be generated with same Code Generation Options. I've do...
Hello. 'Smart Tabs' concept allows to automatically insert tab character for block indentation and space characters for in-block formatting. It's described here. Unfortunately, Visual Studio's 'smart tabs' option in text editor settings just indents text on enter press. Same name, completely different and near useless thing :). So, mayb...
I'm using Ubuntu Server 9.10 AMD Phenom 2 cpu g++ (Ubuntu 4.4.1-4ubuntu9) 4.4.1 trying to run the application pftp-shit v 1.11, which runs successfully until the remote file list is going to be saved (into .pftp//pftpfxp--). The following code in tcp.cc is executed successfully: int outfile_fd = open(name, O_CREAT | O_TRUNC | O_RDWR |...
Hello, I am finding it difficult to determine the length of the columns in a 2D unsigned short pointer array. I have done memory allocation correctly as far as I know. and can print them correctly. plz see the following code segment: int number_of_array_index_required_for_pointer_abc=3; char A[3][16]; strcpy(A[0],"Hello"); strcpy(A[1...
My application is to represent shapes on the Earth's (using a sphere is sufficient) surface. Those can be points, lines, and polygons. Coordinates should be defined by using degrees or radians (just like geographic coordinates). A (straight) line for example should be defined by two coordinates and use the great circle (http://en.wiki...
I have a device to acquire XRay images. Due to some technical constrains, the detector is made of heterogeneous pixel size and multiple tilted and partially overlapping tiles. The image is thus distorted. The detector geometry is known precisely. I need a function converting these distorted images into a flat image with homogeneous pixe...
I wrote a small program in VS2005 to test whether C++ global operator new can be overloaded. It can. #include "stdafx.h" #include "iostream" #include "iomanip" #include "string" #include "new" using namespace std; class C { public: C() { cout<<"CTOR"<<endl; } }; void * operator new(size_t size) { cout<<"my overload o...
Hi all i'm trying to make a simple GUI with QT 4.6. i made a separete class that represents the menu bar: MenuBar::MenuBar() { aboutAct = new QAction(tr("&About QT"), this); aboutAct->setStatusTip(tr("Show the application's About box")); connect(aboutAct, SIGNAL(triggered()), this, SLOT(about())); quitAct = new QAction...
I have a large C++ function which uses OpenCV library and running on Windows with cygwin g++ compiler. At the end it gives Aborted(core dumped) but the function runs completely before that. I have also tried to put the print statement in the end of the function. That also gets printed. So I think there is no logical bug in code which wil...
template<class T> class Array { public:void mf(); #1 }; template class Array<char>; // explicit instantiation #2 template void Array<int>::mf(); // explicit instantiation #3 void main() { Array<double> a; // implicit instantiation // my question is how to call mf() in #2 (explict declaration)from main() } ...
I'm currently working on a class to create and read out packets send through the network, so far I have it working with 16bit and 8bit integers (Well unsigned but still). Now the problem is I've tried numerous ways of copying it over but somehow the _buffer got mangled, it segfaulted, or the result was wrong. I'd appreciate if someone ...
Updated: please see this other thread instead, all this COM stuff is not part of the problem. One of our apps has a COM interface which will launch a dialog, e.g: STDMETHODIMP CSomeClass::LaunchDialog(BSTR TextToDisplay) { CDialog *pDlg = new CSomeDialog(TextToDisplay); pDlg->BringWindowToTop(); } For some reason when the COM m...
Hi, I'm new in QT, and I'm just testing out the MOC. For a given class: class Counter : public QObject { Q_OBJECT int m_value; public: Counter() {m_value = 0;} ~Counter() {} int value() {return m_value;} public slots: void setValue(int value); signals: void valueChanged(int newValue); }; I want to get a list of all methods in ...
I have a large framework consisting of many C++ classes. Is there a way using any tools at runtime, to trace all the C++ objects that are being constructed and currently exist? For example, at a certain time t1, perhaps the application has objects A1, A2 and B3, but at time t2, it has A1, A4, C2 and so on? This is a cross platform fra...