|
Science, Technology and Engineering |
 |
Principal Author: James Sherring
|
| Features |
|---|
Dimsym is a program primarily for the determination of symmetries of differential equations. It also can be used to compute symmetries of distributions of vector fields or differential forms on finite dimensional manifolds, symmetries of geometric objects (eg, isometries), and also to solve linear partial differential equations.
To use its primary function the user specifies a system of ordinary and/or partial differential equations and the type of symmetry to be found (Lie point, Lie-Backlund or some user-provided ansatz). Dimsym then produces the corresponding determining equations (a system of linear partial differential equations for the generator of the generic symmetry). It proceeds to solve these equations, reporting any special conditions required to produce a solution. Finally, Dimsym gives the generators of the symmetry group (which may of course be infinite dimensional).
The program allows the user to compute Lie brackets, vector derivatives and so on and it has an interface with the REDUCE package EXCALC so that all the machinery of calculus on manifolds can be utilised from within the program. Its use can be interactive or batch and there are extensive tracing options.
If you don't have REDUCE or you work on a stand alone IBM compatible you may wish to use Alan Head's LIE program.
