Introduction to C++

1. Introduction to C++ Shirley Moore http://www.cs.utep.edu/svmoore/ svmoore@utep.edu CPS 5401, Fall 2013 http://svmoore.pbworks.com/

2. History of C++ • Reference: www.cplusplus.com/ • History going back to 1979, when BjarneStroustrup was doing work for his Ph.D. thesis • Stroustrup was working with the Simula 67 language, regarded as the first language to support the object-oriented programming paradigm, but it was too slow to be of practical use. • Goal was to add object-oriented programming into the C language without sacrificing speed or low-level functionality. • His language included classes, basic inheritance, inlining, default function arguments, and strong type checking in addition to all the features of the C language. • In 1983, the name of the language was changed from C with Classes to C++. New features included virtual functions and function overloading. • In 1985, Stroustrup’sThe C++ Programming Language was published. Also in 1985, C++ was implemented as a commercial product. • In 1990, The Annotated C++ Reference Manual was pubslished and Borland's Turbo C++ compiler was released as a commercial product. • In 1998, the C++ standards committee published the first international standard for C++ ISO/IEC 14882:1998, informally known as C++98. • In mid-2011, the new C++ standard (dubbed C++11) was finished. New features included a standard threading library.

3. Features of C++ • C++ ...is an open ISO-standardized language....is a compiled language....is a strongly-typed unsafe language....supports both manifest and inferred typing....supports both static and dynamic type checking....offers many paradigm choices....is portable....is upwards compatible with C....has vast library support.

4. Classes • Object-oriented programming concept • A class is a construct that is used to create instances of itself – referred to as class instances or objects • A class defines members that enable its instances to have state and behavior. • Data field members (member variables or instance variables) enable a class instance to maintain state. • Methods enable the behavior of class instances. • Classes support information encapsulation. • Classes define the type of their instances.

5. Inheritance • Inheritance is a mechanism of reusing and extending existing classes, thus producing hierarchical relationships between them. • A new class is derived from the base class. • Can add new data members and member functions to the derived class. • Can modify the implementation of existing member functions or data by overriding base class member functions or data in the newly derived class. • Multiple inheritance allows you to create a derived class that inherits properties from more than one base class.

6. Polymorphic Functioins • Polymorphic functions are functions that can be applied to objects of more than one type. In C++, polymorphic functions are implemented in two ways: • Overloaded functions are statically bound at compile time. • A virtual function is a function that can be called for a number of different user-defined types that are related through derivation. Virtual functions are bound dynamically at run time.

7. HPC Codes Written in C++ • MPQC computational chemistry code • www.mpqc.org • C++ development version of GAMESS • LAMMPS molecular dynamics code • lammps.sandia.gov • NAMD molecular dynamics code • www.ks.uiuc.edu/Research/namd/ • Object-oriented math libraries (parts written in Fortran and/or C and/or using code generators) • PETSc • Trilinos • Many others