Draw a knot diagram by clicking on the grid (A). Overcrossings are defined by left-clicking when arcs intersect, undercrossings by right-clicking. Closing the knot completes the diagram and then crossings can be toggled over/under by clicking on them. The Jones polynomial is displayed in the output window (B) once Calculate is pressed. To erase the knot, press Clear . Start the program by clicking on the image below

This program was conceived and written by Tim O'Leary, as part of a fourth-year Mmath project in 2002. It is based on the paper:
A matrix for computing the Jones polynomial of a knot, Topology, Volume 34, Issue 3, July 1995, Pages 717-729
MA3F2 page