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ampl / mp

An open-source library for mathematical programming
https://mp.ampl.com
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Gurobi CBasis status #152

Open glebbelov opened 2 years ago

glebbelov commented 2 years ago

Gurobi 9.5 needs a complete basis.

For non-basic constraints, should we report low/upp/equ (currenlty 'none' for non-range constraints, which leads to unaccepted basis after adding new constraints and resolving, as we don't know in the driver which constraints are new. It seems we should set some of new constraints to bas for Gurobi to accept the basis)?

glebbelov commented 2 years ago

Reporting 'sup' for non-basic constraints. Moreover, on basis input, assuming new constraints (those with .sstatus 'none') are active and setting them as non-basic. Could improve this by looking at the slack.

4er4er4er commented 2 years ago

See my comment on ampl/solvers-private#47.

glebbelov commented 2 years ago

With setting new constraints as non-basic, warmstart often succeeds. Might improve this by looking at slack