Bug in Nightly: Default Value Not Correctly Set

[OPMUSER]

Default value should be true not false.

` [/build/opm-simulators-2020-06-30-git6d644da/opm/simulators/linalg/ISTLSolverEbos.hpp:183] Flexible solvers and CPR need the well contribution in the matrix. Please run with --matrix-add-well-contributions=true

MatrixAddWellContributions="false" # default: "0" ` NOR01-PRED01-OPM-NB-R00.zip

[blattms]

I be to differ. true is unstable for some models hence the default is false. Only CPR is still different and that should either be fixed or the default neglected. @atgeirr @hnil

[atgeirr]

A limitation of our current parameter system is that defaults can not depend on other parameters. The reasonable thing to do here would be to have the default be true with CPR and false with ILU0, but we cannot do that at the moment. An alternative would be to remove the parameter from user control and let its value be decided by the CPR-or-not choice, but that is also not good for the following reasons:

• The --matrix-add-well-contributions=true option is not implemented yet for MS wells.
• Work is ongoing (although paused at the moment) to make the false variant (the operator approach) work well also with more complex preconditioners such as CPR, we need to test these against each other.

That said, I think the particular issue of not being allowed to run CPR with the false option is no longer true with OPM/opm-simulators#2706. Work on that is also paused, but I hope to get it in before the next release.