Posted by Sherri Arrieta on August 11, 1998 at 16:32:33:
In Reply to: VODE solver....supplying Jacobian posted by Jason on August 08, 1998 at 10:50:38:
: HI
: I am trying to solve a relatively small number of stiff
: First order ODE's. To do this I am trying to use
: VODE.
: Though this program can calculate the Jacobian, the
: instructions suggest that, if possible, it is supplied.
: Is there any reason why a Jacobian that I supply would
: be better than letting the code calculate one itself?
It saves time (a substantial amount of time! in some cases
but for a small system of ODEs you may not even notice)
and computer memory space to supply a jacobian subroutine.
: Also, what are the advantages of banding the Jacobian
: and why would I want to do this?
Once again it saves computer memory space but not all
jacobians can be easily banded. I wouldn't even bother
trying.
: Thanks in advance
: Jason