Hamiltonian system solver using leapfrog integration, calculating interpolated shadow Hamiltonians up to order 24. Can be easily modified to new potentials by creating new implementations for the functions: 1. initial_conditions 2. force_eval 3. potential_eval [optional: 4. truncated_eval ] Robert Engle, June 2003 University of Illinois at Urbana-Champaign, Computer Science Department >----------------------------------------------------------------------------< These files need not be changed to implement a new potential >----------------------------------------------------------------------------< main.h - enumerated types, simulation data structure, & basic function declarations main.c - interpolated shadow Hamiltonian formula coefficients (initialized to 1D arrays), memory allocation & deallocation, call to leapfrog integrator.h - function declarations related to leapfrog method, energy & shadow energy calculation integrator.c - implementation of leapfrog (with difference table updates), evaluation of energy & shadow energy force.h - function delcarations for force & potential energy difftable.h - data structure to hold table of backward differences (orders 1 - 12) difftable.c - functions to update the q & beta portions of the backward difference table, & to calculate Aij's truncated.h - function declarations for truncated shadow Hamiltonian functions (orders 2, 4, ..., 12), & notes on the origins of truncated modified Hamiltonian code. output.h - function declarations for 3 data output functions output.c - implementations of data output functions >----------------------------------------------------------------------------< These files are specific to certain potentials >----------------------------------------------------------------------------< henon.c - implementation of force_eval and potential_eval for the Henon-Heiles Hamiltonian (2 atom system), and truncated shadow Hamiltonians of orders 2, 4, ..., 12. doublewell.c - ipmlementation of force_eval and potential_eval for a doublewell potential (1 atom system), and truncated shadow Hamiltonians of orders 2, 4, ..., 12.