Interoperable interactive geometry for Europe
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René Grothmann



University of Eichstätt



GER - Germany



Rene Grothmann


René Grothmann is professor for mathematics at the University of Eichstätt, Germany. His scientific interests include approximation theory, esp. complex approximation, and numerical programming. One of his projects in numerical programming is Euler Math Toolbox, a matrix language for Unix and Windows with interval and exact arithmetic and computer algebra support by Maxima.

In 1989, he developed the first version of a dynamic geometry program for the Atari ST for a programming class about object oriented programming. Ports to OS/2 and Windows followed. With the appearance of Java in 1995, a new version was programmed in Java, named Z.u.L. (Zirkel und Lineal) in German, C.a.R. (Compass and Ruler) in English. C.a.R. has then developed into a rapidly growing community driven project. It is now available in a many languages, with many users inside and outside Germany. C.a.R. is associated in the Inter2geo project, especially interested in the development of a common file format.