[Getdp] Can GetDP reuse a stiffness matrix?

[John_V]

I am using GetDP to repeatedly solve electrostatic problems on the same 
mesh. The only thing that changes from one solution to the next is the 
distribution of charges. That is, GetDP is solving K.V = S for V, where 
the stiffness matrix K is every time the same and only S changes. In 
this circumstance it is not in principle necessary to build K from the 
mesh every time. It could just be built the first time and then reused.

I have two questions:

1. Does GetDP presently implement any mechanism to do this? For example, 
is there a way to export the matrix to a file after it is computed, and 
then import it for use the next time GetDP is used?

2. Is this likely to save any (or much) time? Each resolution is taking 
about 15 to 50 minutes on my computer, but I don't know what fraction of 
this is spent building the K matrix and what fraction is actually 
solving the system of equations. I know from watching the output that 
all of the [0% - 10% - ... 90% - Done] convergence messages appear in 
the last minute or so. If those coincide with the solution of the 
equations then it may be that a significant amount of the time is spent 
computing K, in which case this could lead to a big time savings.

John