This commit adds a new member function,
AquiferInterface::initFromRestart()
that consumes a vector<data::AquiferData> constructed from
information in the restart file's SAAQ and XAAQ vectors. At the
moment, we use the initial aquifer pressure, the total produced
liquid volume and the current aquifer pressure at restart.
We implement the interface's member function in terms of the virtual
function
AquiferInterface::assignRestartData()
that must be overridden in derived classes.
Implement a trivial such function for Carter-Tracy aquifers, and a
function that only stores the current aquifer pressure for the
Fetkovich aquifer model.
Additionally, record whether or not the aquifer object was
initialised from a previous solution. If so, don't reset total
produce liquid volumes or aquifer pressures to their base values
from the model input file.
