C++ for Scientists - Technische Universität Dresden

Inheritance
Chapter 6
C ++ is a multi-paradigm language and the paradigm that is most strongly associated with C ++
is ‘Object-Oriented Programming’ (OOP). The authors feel nevertheless that it is not the most
important paradigm for scientific programming because it is inferior to generic programming
for two major reasons:
• Flexibility and
• Performance.
However, the impact of these two disadvantages is negligible in some situations. The performance
is only deteriorated when we use virtual functions (§ 6.1).
OOP in combination with generic programming is a very powerful mechanism to provide a form
of reusability that neither of the paradigms can provide on it own (§ 6.3–§ 6.5).
6.1 Basic Principles
See section ?? from page ?? to page ??.
6.2 Dynamic Selection by Sub-typing
solver base class
The way solvers are selected in AMDiS. The MTL4 solvers generic functions. AMDiS is only
slightly generic but many decisions are made at run-time (by means of pointers and virtual
functions). So, we needed a way to call the generic functions but decide at run time which one.
The dynamic solver selection can be done with classical C features like:
#include
#include
class matrix {};
class vector {};
void cg(const matrix& A, const vector& b, vector& x)
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