Gato - the Graph Animation Toolbox - is a software which visualizes algorithms on graphs. Graphs are mathematical objects consisting of vertices and edges connecting pairs of vertices: think of cities as vertices and interstates as edges connecting two cities. Algorithms might find a shortest path - the fastest route -- or a minimal spanning tree or solve one of other interesting problems on graphs: maximal-flow, weighted and non-weighted matching and min-cost flow. Visualisation means linking cause - the statements of an algorithm - immediately to an effect - changes to the graph the algorithm has as its input - by terms of blinking, changing colors and other visual effects. You can read more about the concepts involved, see examples using HTML or see a video of an example session.

Gato has been developed at the ZAIK/ZPR, an institute at the Unversity of Cologne. Gato is (c) 1998, 1999 ZAIK/ZPR, Universität zu Köln and distributed under the Gnu Public License. It runs on all plattforms Python and Tcl/Tk run on, which includes at least Unix, Linux, MacOS and Windows 95/98/NT.

Gato is used in CATBox (the Combinatorial Algorithm Toolbox - an interactive course on discrete mathematics) to be published by Springer Verlag and has been used for courses on algorithms - both in the Computer Science and the Mathematics department - taught at the University of Cologne.