C.a.R.

Compass and Ruler - Construct and Rule

C.a.R. simulates constructions with a pair of compasses and a ruler on a computer. By moving basic points, students can

• experience changes in the construction,
• check the construction for correctness,
• discover relations between geometric objects.

Moreover, tracks of points or polar sets of lines can be generated to establish new conjectures and gain geometrical insights.

With functions, curves and expressions, C.a.R goes far beyond compass and ruler. With the powerful macros very complicated constructions can be explored. Other geometries, elliptic or hyperbolic, can be explored too. Graphics can be exported in various formats.

Constructions are saved in an open XML based format, and the program itself is open source under the Gnu Public License.

The program is written in Java and available for all operating systems that support Java, such as Windows, Mac OS, or Linux. A Java version must be installed.

I take this opportunity to thank all people that helped me with ideas, debugging or testing this software. Without them, this would not be possible.

C.a.R. has been developed by René Grothmann from the Catholic University of Eichstätt.