C++ for Scientists - Technische Universität Dresden

C ++ Libraries for Scientific Computing
Chapter 11
TODO: Introducing words.
11.1 GLAS: Generic Linear Algebra Software
11.1.1 Introduction
Software kernels for dense and sparse linear algebra have been developed over many decades.
The development of the BLAS [?] [?] [?] [?] [?] in FORTRAN and later the similar work in
C++, see MTL [?], Blitz++, to name a few.
Currently, more and more scientific software is written in C++, but the language does not
provide us with dense and sparse vector and matrix concepts and algorithms, as this is the
case for Matlab. This makes exchanging C++ software harder than, for example, Fortran 90
software, which has dense vector and matrix concepts defined in the language. Note that
Fortran 90 does not have sparse and structured matrix types such as symmetric or upper
triangular, or banded matrices.
11.1.2 Goal
The goal of the GLAS project is to open the discussion on standardization for C++ programming.
The goal is not to present a standard as such, but may be a first step to achieve this
goal.
We realize that this is very ambitious. We think, the GLAS proposal meets the goals, but the
internals are still rather complicated, which makes extensions less straightforward. GLAS is a
generic software package using advanced meta programming tools such as the Boost MPL, but
this is invisible to the user who does not want to add extensions to GLAS. A minor knowledge
about template programming and expression templates is required for making proper use of the
software.
This version does not use Concept C++, since we have encountered instability problems with
the Concept-GCC compiler and found it hard to work with expression-templates.
243