Hi, I have a vector of points, and I need to get those which are at a distance less than a value from a given point. I could do it with a simple loop, but is there a better way to do it? Thanks in advance ...
Hi, I'm trying to implement a multi threaded, recursive file search logic in Visual C++. The logic is as follows: Threads 1,2 will start at a directory location and match the files present in the directory with the search criteria. If they find a child directory, they will add it to a work Queue. Once a thread finishes with the files in...
Possible Duplicate: How to make elements of vector unique? (remove non adjacent duplicates) Is there any standard algorithm which is provided as part of STL algorithms which can remove duplicates from an array while preserving the order. For example, if I have an array like int a[] = {2,1,3,1,4,2}; after the removal of duplica...
I want to change some Perl code into C++. I need to know how to implement nested Perl hashes in C++. I thought of STL as a good choice and used maps. With the help of maps I can create only a simple hash but I do not know how to create a nested hash structure. My Perl hash is like this: %foo = ( "bar1" => { Default => 0, ...
Hi, I'm tring to calculate the standard deviation of a vector of doubles (called A). Now I have a function called StDev that will do this. However, the first few elements of vector A are zero and I need to remove these. To do this I create a sub-array and then pass this to my StDev function as follows: std::vector<double> Array(f...
One of my C++ classes derives from std::vector so that it can act as a container that also perform custom actions on its content. Unfortunately, the compiler complains about the destructor not to be virtual, which I cannot change, since its in the standard library. Am I doing the whole thing wrong (thou shall not derive from STL) or is ...
Hi, Is it safe to use one standard compliant STL in a library, and another in a project that uses that library? For example: //library.h #include <string> //let's say here it uses minGW STL void Foo(std::string& str_mingw); //library.cpp void Foo(std::string& str_mingw) { /*do something*/ } //application.cpp #include "library.h...
I have some code that looks like this: std::set<int> s1, s2, out; // ... s1 and s2 are populated ... std::set_intersection(s1.begin(), s1.end(), s2.begin(), s2.end(), std::inserter(out, out.end())); I've read inserts can be done in amortized constant time if the value being inserted to the...
What is going on? #include <iostream> #include <iterator> #include <sstream> int main() { std::basic_stringbuf<unsigned char> buf; std::basic_istream<unsigned char> stream(&buf); // the next line throws std::bad_cast on g++ 4.4 std::istream_iterator<unsigned char, unsigned char> it(stream); } I've tried stream.write(s...
I'm trying to combine three signal waveforms into a single, interleaved waveform. I need to know the best way to do it in C++ STL. Better solutions would use as much C++ STL style as possible, avoid redundant code, etc. Is there some STL "tuple" type class that would do this for me? I need contiguous storage at all times for backward com...
I need to use bit flags with more than 32 bits (33 to be exact right now). I tried and find std::bitset doesn't handle more than 32 bits (ulong). Do I have to use vector or there's a way to make bitset to work? I am limited to c++98 in this project so I can't use boost. Thanks. Edit: I'd like to do something like this: const uint64 ...
Hi, I need to get all the contents from a stream, without actually extracting them (just like stringstream::str()). I've tried basic_stringbuf::str(), but it behaves incorrectly when the stream is empty. To avoid that case, I had a go at basic_stringbuf::in_avail(), but that hasn't worked out very well either. In the following test ca...
From the title you'd almost assuredly think use set_union to create a list and then check if it's empty. However, the objects I'm comparing are "expensive" to copy. I've looked at includes but that only works if all the items of one list are found in another. I've also looked at mismatch but rejected it for obvious reasons. I can and...
I have a stl set of integers and I would like to iterate through all unique pairs of integer values, where by uniqueness I consider val1,val2 and val2,val1 to be the same and I should only see that combination once. I have written this in python where I use the index of a list (clusters): for i in range(len(clusters) - 1): for j in...
Hi, I have an application with several threads running. I have 2 threads that seem deadlocked when trying to allocate an std::string. Inspecting the backtrace of both threads suggest that at some point one has tried to allocate an std::string, and got a bad_alloc exception. In its catch block, another string is created in an attempt to ...
I am porting some code from linux to windows and am coming up with some strange error. I have the following class: (header) RegionRectangle.h #ifndef __RECTANGLE_H__ #define __RECTANGLE_H__ #include <iostream> using namespace std; class Rectangle { public: Rectangle(int x = 0,int y = 0,int width = 0,int height = 0, int threshold=...
Is there any existing iterator implementation (perhaps in boost) which implement some sort of flattening iterator? For example: unordered_set<vector<int> > s; s.insert(vector<int>()); s.insert({1,2,3,4,5}); s.insert({6,7,8}); s.insert({9,10,11,12}); flattening_iterator<unordered_set<vector<int> >::iterator> it( ... ), end( ... ); for...
hello, i've used search but i didn't find answer satisfying me... so.. this is chunk of code: //VoteContainer.h typedef uint32_t order_id_t; typedef int driver_id_t; class Vote { public: enum DriverVoteResponse {YES, NO, TIMEOUT}; struct DriverResponse { driver_id_t dri...
Hi, I have some original code that manages exception safety like this: void foo() { HDC hdc = //get an HDC HBITMAP hbitmap = //get an HBITMAP HGDIOBJ hbitmapOld = SelectObject(hdc, hbitmap); try { //do something that may throw an exception } catch (...) { SelectObject(hdc, hbitmapOld); thro...
Hello, i am looking for a container, to contain objects like Employee (with info: name, salary, phone ....) that will be possible to once sort it by name (a..z) and other time sort it by salary for example. what is the best way to do it ? i thought about map, but then i define only 1 key to go by would appreciate every idea (not too adva...