Jørn Jensen (1925 – 2007) was one of the earliest
Danish computer
programmer
A programmer, computer programmer or coder is an author of computer source code someone with skill in computer programming.
The professional titles Software development, ''software developer'' and Software engineering, ''software engineer' ...
s. Examined as a
mechanical engineer
Mechanical may refer to:
Machine
* Machine (mechanical), a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement
* Mechanical calculator, a device used to perform the basic operations o ...
, he had worked with electromechanical construction. In 1958, he was employed at the Danish
Regnecentralen
Regnecentralen (RC) was the first Denmark, Danish computer company, founded on 12 October 1955. Through the 1950s and 1960s, they designed a series of computers, originally for their own use, and later to be sold commercially. Descendants of thes ...
(RC), and very soon exhibited an extraordinary programming skill. He developed the main parts of the base programs to the ''Dansk Aritmetisk Sekvens Kalkulator'' (
DASK, ''Danish Arithmetic Sequence Calculator''), the first Danish computer. Among other programs, he designed a set of monitor programs to supervise the program running schedule on DASK. In tight collaboration with
Peter Naur
Peter Naur (25 October 1928 – 3 January 2016) was a Danish computer science pioneer and 2005 Turing Award winner. He is best remembered as a contributor, with John Backus, to the Backus–Naur form (BNF) notation used in describing the syntax ...
and others, he developed reliable, well documented
compiler
In computing, a compiler is a computer program that Translator (computing), translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primaril ...
s for the
ALGOL 60
ALGOL 60 (short for ''Algorithmic Language 1960'') is a member of the ALGOL family of computer programming languages. It followed on from ALGOL 58 which had introduced code blocks and the begin and end pairs for delimiting them, representing a ...
programming language.
[ Mentions Naur's work with Jensen on GIER ALGOL.] In this context, he invented
Jensen's Device, an ingenious exploitation of the name parameters to compute numerical series without using procedure parameters, as is needed in all programming languages, except
ALGOL 60
ALGOL 60 (short for ''Algorithmic Language 1960'') is a member of the ALGOL family of computer programming languages. It followed on from ALGOL 58 which had introduced code blocks and the begin and end pairs for delimiting them, representing a ...
and
Simula
Simula is the name of two simulation programming languages, Simula I and Simula 67, developed in the 1960s at the Norwegian Computing Center in Oslo, by Ole-Johan Dahl and Kristen Nygaard. Syntactically, it is an approximate superset of AL ...
67.
After some 20 years at Regnecentralen, he continued his career in
systems programming
Systems programming, or system programming, is the activity of programming computer system software. The primary distinguishing characteristic of systems programming when compared to application programming is that application programming aims t ...
, and other types, at the
Brown, Boveri & Cie
Brown, Boveri & Cie. (Brown, Boveri & Company; BBC) was a Swiss group of electrical engineering companies. It was founded in Baden bei Zürich, in 1891 by Charles Eugene Lancelot Brown and Walter Boveri who worked at the Maschinenfabrik Oer ...
electrical engineering company.
References
Danish computer programmers
1925 births
2007 deaths
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