Introduction Computational science is about using computers to analyze scientific problems. It is distinct from computer science, which is the study of computers and computation, and it is different from theory and experiment, the traditional forms of science, in that it seeks to gain understanding principally through the analysis of mathematical models on high performance computers. The term computational scientist has been coined to describe scientists, engineers and mathematicians who apply high performance computer technology in innovative and essential ways to advance the state of knowledge in their respective disciplines. More recently, computational science has begun to make inroads into other areas such as economics, music and visual arts. The computational approach to doing science is inherently multidisciplinary: it requires of its practitioners a firm grounding in applied mathematics and computer science in addition to a command of on

Introduction Presently there is no generally accepted definition of Computational Science. In broad terms it is about using computers to analyze scientific problems. Thus we distinguish it from computer science, which is the study of computers and computation, and from theory and experiment, the traditional forms of science. Computational Science seeks to gain understanding principally through the analysis of mathematical models on high performance computers. The term computational scientist has been coined to describe scientists, engineers and mathematicians who apply high performance computer technology in innovative and essential ways to advance the state of knowledge in their respective disciplines. More recently, computational science has begun to make inroads into other areas such as economics, music and visual arts. We shall use the term "computational science" as a convenient shorthand for "computational science and engineering." A well-known characteris

Factory in [GHJ95]. A factory class is used when "a system should be independent of how its products are created, composed, and represented" or when "a system should be configured with one of multiple families of products". Our WireFactory class is not abstract, but we'll explore how to create more than one kind of factory in the exercises by creating an abstract base class from which WireFactory derives. The Gate::clone method outlined in Program Tip 13.9 as a realization of a factory method shares characteristics with the WireFactory class that is a factory class: both isolate object creation so that clients can use objects without knowing how to create them. 13.3.7 Refactoring: Creating a BinaryGate class When I first designed the Gate hierarchy in Fig. 13.5 I anticipated creating classes like And3Gate, an and-gate with three inputs that sets its output only when all three inputs are set. I considered an And3Gate to be a 3-1-gate, a gate with three inputs and one output. The e...

are reaching the stage of development where each new generation

The term ‘recursive’ has had different meanings during the past two centuries among various communities of scholars. Its historical epistemology has already been described by Soare (1996) with respect to the mathematicians, logicians, and recursive-function theorists. The computer practitioners, on the other hand, are discussed in this paper by focusing on the definition and implementation of the ALGOL60 programming language. Recursion entered ALGOL60 in two novel ways: (i) syntactically with what we now call BNF notation, and (ii) dynamically by means of the recursive procedure. As is shown, both (i) and (ii) were introduced by linguistically-inclined programmers who were not versed in logic and who, rather unconventionally, abstracted away from the down-to-earth practicalities of their computing machines. By the end of the 1960s, some computer practitioners had become aware of the theoretical insignificance of the recursive procedure in terms of computability, though without relying on recursive-function theory. The presented results help us to better understand the technological ancestry of modernday computer science, in the hope that contemporary researchers can more easily build upon its past.