Egon Zakrajšek (July 7, 1941 – September 2002) was a Slovene

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

and

computer scientist A computer scientist is a scientist who specializes in the academic study of computer science. Computer scientists typically work on the theoretical side of computation. Although computer scientists can also focus their work and research on ...

. Zakrajšek was born in

Ljubljana {{Infobox settlement , name = Ljubljana , official_name = , settlement_type = Capital city , image_skyline = {{multiple image , border = infobox , perrow = 1/2/2/1 , total_widt ...

SFR Yugoslavia The Socialist Federal Republic of Yugoslavia (commonly abbreviated as SFRY or SFR Yugoslavia), known from 1945 to 1963 as the Federal People's Republic of Yugoslavia, commonly referred to as Socialist Yugoslavia or simply Yugoslavia, was a country ...

(today

Slovenia Slovenia, officially the Republic of Slovenia, is a country in Central Europe. It borders Italy to the west, Austria to the north, Hungary to the northeast, Croatia to the south and southeast, and a short (46.6 km) coastline within the Adriati ...

). He became an orphan even before he started school. He went to elementary school and gymnasium in

Jesenice Jesenice (, ''Leksikon občin kraljestev in dežel zastopanih v državnem zboru'', vol. 6: Kranjsko. 1906. Vienna: C. Kr. Dvorna in Državna Tiskarna, p. 144.) is the tenth-largest town in Slovenia, located in the traditional province of Upper C ...

. He was a good student and he soon showed his talents and abilities. He graduated from technical mathematics at the Department of mathematics and physics of the then Faculty for natural sciences and technology (FNT) of the

University of Ljubljana The University of Ljubljana (, , ), abbreviated UL, is the oldest and largest university in Slovenia. It has approximately 38,000 enrolled students. The university has 23 faculties and three art academies with approximately 4,000 teaching and re ...

. He received his

Master's degree A master's degree (from Latin ) is a postgraduate academic degree awarded by universities or colleges upon completion of a course of study demonstrating mastery or a high-order overview of a specific field of study or area of professional prac ...

from the

University of Zagreb The University of Zagreb (, ) is a public university, public research university in Zagreb, Croatia. It is the largest Croatian university and one of the oldest continuously operating universities in Europe. The University of Zagreb and the Unive ...

for his work ''Numerična realizacija Ritzovega procesa'' (''Numerical realization of the Ritz process'') and his

doctorate A doctorate (from Latin ''doctor'', meaning "teacher") or doctoral degree is a postgraduate academic degree awarded by universities and some other educational institutions, derived from the ancient formalism '' licentia docendi'' ("licence to teach ...

in 1978 in Ljubljana with his dissertation ''O invariantni vložitvi pri reševanju diferencialnih enačb'' (''About the invariable embedding in solving of differential equations''). Professor Zakrajšek was one of the pioneers of

computer science Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, ...

in Slovenia. He became an expert on the first

computer A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic set ...

s of the University of Ljubljana, the Zuse Z-23 and its successor the

IBM 1130 The IBM 1130 Computing System, introduced in 1965, was IBM's least expensive computer at that time. A binary 16-bit machine, it was marketed to price-sensitive, computing-intensive technical markets, like education and engineering, succeeding th ...

. He later participated in the development of

programming language A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually def ...

s, tools and

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

s. At the same time he wrote textbooks and manuals for them: for Z-23 assembly,

Algol ALGOL (; short for "Algorithmic Language") is a family of imperative computer programming languages originally developed in 1958. ALGOL heavily influenced many other languages and was the standard method for algorithm description used by the ...

, Fortran,

Algol 68 ALGOL 68 (short for ''Algorithmic Language 1968'') is an imperative programming language member of the ALGOL family that was conceived as a successor to the ALGOL 60 language, designed with the goal of a much wider scope of application and ...

, Pascal, for domestic structran. In 1982 he set off for the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

and he became the manager of programming equipment at the

Cromemco Cromemco, Inc. was a Mountain View, California microcomputer company known for its high-end Z80-based S-100 bus computers and peripherals in the early days of the personal computer revolution. The company began as a partnership in 1974 between ...

company. In 1994 he returned to homeland, where he was again a professor. With his advocacy for the C language and open operating systems, that is,

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

and

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

, he helped to modernize the lessons of computer science. He additionally became an expert for

TeX Tex, TeX, TEX, may refer to: People and fictional characters * Tex (nickname), a list of people and fictional characters with the nickname * Tex Earnhardt (1930–2020), U.S. businessman * Joe Tex (1933–1982), stage name of American soul singer ...

LaTeX Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latices are found in nature, but synthetic latices are common as well. In nature, latex is found as a wikt:milky, milky fluid, which is present in 10% of all floweri ...

and

MATLAB MATLAB (an abbreviation of "MATrix LABoratory") is a proprietary multi-paradigm programming language and numeric computing environment developed by MathWorks. MATLAB allows matrix manipulations, plotting of functions and data, implementat ...

. Beside his computer science skills he was also an excellent mathematician with a broad profile. He taught and solved problems from many fields: the usage of mathematics in natural and social sciences,

statistics Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a s ...

mechanics Mechanics () is the area of physics concerned with the relationships between force, matter, and motion among Physical object, physical objects. Forces applied to objects may result in Displacement (vector), displacements, which are changes of ...

, classical

applied mathematics Applied mathematics is the application of mathematics, mathematical methods by different fields such as physics, engineering, medicine, biology, finance, business, computer science, and Industrial sector, industry. Thus, applied mathematics is a ...

discrete mathematics Discrete mathematics is the study of mathematical structures that can be considered "discrete" (in a way analogous to discrete variables, having a bijection with the set of natural numbers) rather than "continuous" (analogously to continuous f ...

graph Graph may refer to: Mathematics *Graph (discrete mathematics), a structure made of vertices and edges **Graph theory, the study of such graphs and their properties *Graph (topology), a topological space resembling a graph in the sense of discret ...

and

network theory In mathematics, computer science, and network science, network theory is a part of graph theory. It defines networks as Graph (discrete mathematics), graphs where the vertices or edges possess attributes. Network theory analyses these networks ...

linear programming Linear programming (LP), also called linear optimization, is a method to achieve the best outcome (such as maximum profit or lowest cost) in a mathematical model whose requirements and objective are represented by linear function#As a polynomia ...

operational research Operations research () (U.S. Air Force Specialty Code: Operations Analysis), often shortened to the initialism OR, is a branch of applied mathematics that deals with the development and application of analytical methods to improve management and ...

es,

numerical analysis Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic computation, symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of ...

References

# Marija Vencelj, ''Umrl je prof. dr. Egon Zakrajšek'' (''Professor Dr. Egon Zakrajšek has died''), (Obzornik mat, fiz. 49 (2002) 6, pp 184 – 186). 1941 births 2002 deaths Scientists from Ljubljana Slovenian computer scientists 20th-century Slovenian mathematicians Faculty of Science, University of Zagreb alumni University of Ljubljana alumni University of Zagreb alumni Academic staff of the University of Ljubljana {{Slovenia-scientist-stub