This sub-chapter contains the specifications of the integrators
from the
DASSL package,
Brenan et al. (1996).
The DASSL integrator
nag_dae_ivp_dassl_gen (d02nec) is designed for solving systems of the form,
. These formulations permit solution of differential/algebraic systems
(DAEs). The facilities provided are essentially those of the explicit solvers.
The DASSL integrator,
nag_dae_ivp_dassl_gen (d02nec), has an associated setup function
nag_dae_ivp_dassl_setup (d02mwc) which must be called first. On return from the integrator, if it is feasible to continue the integration, the associated continuation call function is
nag_dae_ivp_dassl_cont (d02mcc) may be called to rest various integration parameters. The structure of the Jacobian is assumed to be full unless
nag_dae_ivp_dassl_linalg (d02npc) is called following a call to the setup function to specify that the Jacobian is banded and to supply its bandwidths.
The DASSL integrator
nag_dae_ivp_dassl_gen (d02nec) can solve DAEs of the fully implicit form
and therefore has increased functionality over the SPRINT integrators. Additionally
nag_dae_ivp_dassl_gen (d02nec) can be used to solve difficult algebraic problems by continuation; for example, the nonlinear algebraic problem
can be solved by integrating solutions of
where the solution to
is known. The solution of this type of problem is illustrated in
Section 10 in
nag_dae_ivp_dassl_gen (d02nec).
Berzins M and Furzeland R M (1985) A user's manual for SPRINT – A versatile software package for solving systems of algebraic, ordinary and partial differential equations: Part 1 – Algebraic and ordinary differential equations Report TNER.85.085 Shell Research Limited