[Bridges] fix deleting variable in bridged objective #2150
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Some solvers error getting ObjectiveFunctionType if objective is not set.
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@blegat can you take a look? This is fairly urgent because it broke tests for CPLEX and Gurobi |
| ::Vector{MOI.VariableIndex}, | ||
| ::Type{F}, | ||
| ) where {F} | ||
| # Nothing to do here. The variables can be deleted without changing the type |
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Suppose the objective is a quadratic function that is bridged with Objective.Slack and then Constraint.QuadtoSOC, we should still update the function so that the corresponding SOC constraint is updated.
This can be done in a separate PR though
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I think that happens automatically. This is just a special case where deleting a variable can unset the objective, rather than just modify the existing function.
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I don't think it does. I think the variable deletion API kind of assumes that all bridges are affine so since the deletion commutes with affine operations then it's fine to skip the bridges and delete the solver model directly but there is one notable exception which is the QuadtoSOC bridge. We should maybe check but it's best we open a separate issue
Some solvers error getting ObjectiveFunctionType if objective is not set. (x-ref jump-dev/CPLEX.jl#433)
I need to manually test this with CPLEX and Gurobi: