Implementation of an efficient logarithmic-Hamiltonian three-body code

The numerical integration of the gravitational few-body problem using the logarithmic-Hamiltonian leapfrog algorithm has been found to produce highly accurate results, especially when combined with the extrapolation method. We describe in detail an implementation of the algorithm to the three-body problem. The considered algorithm has proved itself in numerous simulations and is believed to have led to one of the simplest well working codes for the problem. The advantage of the present code is its relative simplicity since no coordinate transformations are required and therefore adaptations to special purposes are straightforward.

► The implementation of the logarithmic-Hamiltonian three-body algorithm has been discussed in details so that programming should be straightforward.
► The method is useful because of its simplicity so that many modifications for special purposes are easy.
► The accuracy is high, comparable to the use of the celebrated KS-transformation.
► Different versions of the code are available on request.