I have an approach which I think is interesting and a bit different from the rest. The main difference in my approach, compared to some of the others, is in how the image segmentation step is performed–I used the DBSCAN clustering algorithm from Python’s scikit-learn; it’s optimized for finding somewhat amorphous shapes that may not … Read more
PDF versions of the standard As of 1st September 2014 March 2022, the best locations by price for the official C and C++ standards documents in PDF seem to be: C++20 – ISO/IEC 14882:2020: 212 CAD (about $165 US) from csagroup.org C++17 – ISO/IEC 14882:2017: $90 NZD (about $65 US) from Standards New Zealand C++14 … Read more
The typical way is as follows: enum Foo { One, Two, Three, Last }; for ( int fooInt = One; fooInt != Last; fooInt++ ) { Foo foo = static_cast<Foo>(fooInt); // … } Please note, the enum Last is meant to be skipped by the iteration. Utilizing this “fake” Last enum, you don’t have to … Read more
Each element of the container is a map<K, V>::value_type, which is a typedef for std::pair<const K, V>. Consequently, in C++17 or higher, you can write for (auto& [key, value]: myMap) { std::cout << key << ” has value ” << value << std::endl; } or as for (const auto& [key, value]: myMap) { std::cout << … Read more
If you have a C++11 compiler, I would suggest using a range-based for-loop (see below); or else use an iterator. But you have several options, all of which I will explain in what follows. Range-based for-loop (C++11) In C++11 (and later) you can use the new range-based for-loop, which looks like this: std::vector<char> path; // … Read more
#pragma once does have one drawback (other than being non-standard) and that is if you have the same file in different locations (we have this because our build system copies files around) then the compiler will think these are different files.
You can achieve this like following : map<string, int>::iterator it; for (it = symbolTable.begin(); it != symbolTable.end(); it++) { std::cout << it->first // string (key) << ‘:’ << it->second // string’s value << std::endl; } With C++11 ( and onwards ), for (auto const& x : symbolTable) { std::cout << x.first // string (key) << … Read more
Note: Most of the answers cover function pointers which is one possibility to achieve “callback” logic in C++, but as of today not the most favourable one I think. What are callbacks(?) and why to use them(!) A callback is a callable (see further down) accepted by a class or function, used to customize the … Read more
[Executive Summary: Use ++i if you don’t have a specific reason to use i++.] For C++, the answer is a bit more complicated. If i is a simple type (not an instance of a C++ class), then the answer given for C (“No there is no performance difference”) holds, since the compiler is generating the … Read more
From Wikipedia’s Virtual function … In object-oriented programming, in languages such as C++, and Object Pascal, a virtual function or virtual method is an inheritable and overridable function or method for which dynamic dispatch is facilitated. This concept is an important part of the (runtime) polymorphism portion of object-oriented programming (OOP). In short, a virtual … Read more