; † 10 November 1970 in Zürich

Zürich

Zurich is the largest city in Switzerland and the capital of the canton of Zurich. It is located in central Switzerland at the northwestern tip of Lake Zurich...

) was a Swiss mathematician

Mathematician

A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....

 and a pioneer of modern numerical mathematics and computer science

Computer science

Computer science or computing science is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems...

.

Life

Heinz Rutishauser's father died when he was 13 years old and his mother died three years later, so together with his younger brother and sister he went to live in their uncle's home. From 1936, Rutishauser studied mathematics at the ETH Zürich

ETH Zurich

The Swiss Federal Institute of Technology Zurich or ETH Zürich is an engineering, science, technology, mathematics and management university in the City of Zurich, Switzerland....

 where he graduated in 1942. From 1942 to 1945 he was assistant of Walter Saxer at the ETH and from 1945 to 1948 a mathematics teacher in Glarisegg and Trogen. In 1948 he received his PhD from ETH with a well-received thesis on complex analysis

Complex analysis

Complex analysis, traditionally known as the theory of functions of a complex variable, is the branch of mathematical analysis that investigates functions of complex numbers. It is useful in many branches of mathematics, including number theory and applied mathematics; as well as in physics,...

.

From 1948 to 1949 Rutishauser was in the USA at the Universities

University

A university is an institution of higher education and research, which grants academic degrees in a variety of subjects. A university is an organisation that provides both undergraduate education and postgraduate education...

 of Harvard and Princeton

Princeton University

Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....

 in order to study the state of the art in computing. From 1949 to 1955 he was a research associate at the Institute for Applied Mathematics at ETH Zürich recently founded by Eduard Stiefel

Eduard Stiefel

Eduard L. Stiefel was a Swiss mathematician. Together with Cornelius Lanczos and Magnus Hestenes, he invented the conjugate gradient method, and gave what is now understood to be a partial construction of the Stiefel–Whitney classes of a real vector bundle, thus co-founding the study of...

, where he worked together with Ambros Speiser on the development of the first Swiss computer ERMETH. He contributed in particular in the field of compiler

Compiler

A compiler is a computer program that transforms source code written in a programming language into another computer language...

 pioneering work and was eventually involved in defining the programming language

Programming language

A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine and/or to express algorithms precisely....

 Algol 60

ALGOL 60

ALGOL 60 is a member of the ALGOL family of computer programming languages. It gave rise to many other programming languages, including BCPL, B, Pascal, Simula, C, and many others. ALGOL 58 introduced code blocks and the begin and end pairs for delimiting them...

.

In 1951 Rutishauser became a Privatdozent

Privatdozent

Privatdozent or Private lecturer is a title conferred in some European university systems, especially in German-speaking countries, for someone who pursues an academic career and holds all formal qualifications to become a tenured university professor...

, in 1955 he was appointed extraordinary professor and 1962 Associate Professor of Applied Mathematics at the ETH. In 1968 he became the head of the Group for Computer Science which later became the Computer Science Institute and ultimately in 1981 The Division of Computer Science at ETH Zürich.

At least since the 1950s Rutishauser suffered from heart problems. In 1964 he suffered a heart attack from which he recovered. He died on 10 November 1970 in his office from acute heart failure. After his untimely death, his wife Margaret took care of the publication of his posthumous works.

Papers

• Automatische Rechenplanfertigung. Habilitationsschrift ETHZ, 1951.
• Automatische Rechenplanfertigung bei programmgesteuerten Rechenmaschinen. Basel: Birkhäuser, 1952.
• Some programming techniques for the ERMETH, JACM, 2(1), pp. 1–4, Januar 1955.
• Der Quotienten-Differenzen-Algorithmus. Basel: Birkhäuser, 1957.
• Vorlesungen über numerische Mathematik. Band I: Gleichungssysteme, Interpolation und Approximation. Martin Gutknecht (Hrsg.). Basel: Birkhäuser, 1976. ISBN 3-7643-0810-9.
• Vorlesungen über numerische Mathematik. Band II: Differentialgleichungen und Eigenwertprobleme. Martin Gutknecht (Hrsg.). Basel: Birkhäuser, 1976. ISBN 3-7643-0850-8.
• Heinz Rutishauser, Ambros Paul Speiser, Eduard Stiefel: Programmgesteuerte digitale Rechengeräte (Elektronische Rechenmaschinen). Basel: Birkhäuser, 1951.
• Hans Rudolf Schwarz, Heinz Rutishauser, Eduard Stiefel: Numerik symmetrischer Matrizen. Stuttgart: Teubner, 1972, 2. Auflage, ISBN 3-519-12311-8.
• Numerische Prozeduren. Aus Nachlass und Lehre. Walter Gander (Hrsg.). Basel: Birkhäuser, Mai 1998, ISBN 3-7643-0874-5.

External links

• My years with Rutishauser by Friedrich L. Bauer
  Friedrich L. Bauer
  Friedrich Ludwig Bauer is a German computer scientist and professor emeritus at Technical University of Munich.-Life:...
  
  (PDF, englisch; 62 kB)
• Biography at the ETH Zürich