Computing Constraints with Polyhedra

[chelseas]

I get the following error:

julia> for (F, S) in list_of_constraint_types(model)
                           for con in all_constraints(model, F, S)
                               if MOI.get(model, MOI.ConstraintConflictStatus(), con) == MOI.IN_CONFLICT
                                   push!(conflict_constraint_list, con)
                                   println(con)
                               end
                           end
                       end
-xerr_1 + z0[2] = 0.0
xerr_1 = -0.037020325660705566
-z0[2] ≤ 0.0
ERROR: ArgumentError: Bridge of type `Polyhedra.PolyhedraToLPBridge{Float64, MathOptInterface.ScalarAffineFunction{Float64}}` does not support accessing the attribute `MathOptInterface.ConstraintConflictStatus()`.
Stacktrace:
  [1] get(#unused#::MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, attr::MathOptInterface.ConstraintConflictStatus, bridge::Polyhedra.PolyhedraToLPBridge{Float64, MathOptInterface.ScalarAffineFunction{Float64}})
    @ MathOptInterface.Bridges ~/.julia/packages/MathOptInterface/YDdD3/src/Bridges/bridge.jl:76
  [2] (::MathOptInterface.Bridges.var"#55#56"{MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, MathOptInterface.ConstraintConflictStatus})(bridge::Polyhedra.PolyhedraToLPBridge{Float64, MathOptInterface.ScalarAffineFunction{Float64}})
    @ MathOptInterface.Bridges ~/.julia/packages/MathOptInterface/YDdD3/src/Bridges/bridge_optimizer.jl:1206
  [3] (::MathOptInterface.Bridges.var"#1#2"{MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, MathOptInterface.ConstraintIndex{MathOptInterface.VectorOfVariables, Polyhedra.PolyhedraOptSet{Float64, DefaultPolyhedron{Float64, MixedMatHRep{Float64, Matrix{Float64}}, MixedMatVRep{Float64, Matrix{Float64}}}}}, MathOptInterface.Bridges.var"#55#56"{MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, MathOptInterface.ConstraintConflictStatus}})()
    @ MathOptInterface.Bridges ~/.julia/packages/MathOptInterface/YDdD3/src/Bridges/bridge_optimizer.jl:291
  [4] call_in_context(map::MathOptInterface.Bridges.Variable.Map, bridge_index::Int64, f::MathOptInterface.Bridges.var"#1#2"{MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, MathOptInterface.ConstraintIndex{MathOptInterface.VectorOfVariables, Polyhedra.PolyhedraOptSet{Float64, DefaultPolyhedron{Float64, MixedMatHRep{Float64, Matrix{Float64}}, MixedMatVRep{Float64, Matrix{Float64}}}}}, MathOptInterface.Bridges.var"#55#56"{MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, MathOptInterface.ConstraintConflictStatus}})
    @ MathOptInterface.Bridges.Variable ~/.julia/packages/MathOptInterface/YDdD3/src/Bridges/Variable/map.jl:455
  [5] call_in_context(map::MathOptInterface.Bridges.Variable.Map, ci::MathOptInterface.ConstraintIndex{MathOptInterface.VectorOfVariables, Polyhedra.PolyhedraOptSet{Float64, DefaultPolyhedron{Float64, MixedMatHRep{Float64, Matrix{Float64}}, MixedMatVRep{Float64, Matrix{Float64}}}}}, f::Function)
    @ MathOptInterface.Bridges.Variable ~/.julia/packages/MathOptInterface/YDdD3/src/Bridges/Variable/map.jl:486
  [6] call_in_context(b::MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, ci::MathOptInterface.ConstraintIndex{MathOptInterface.VectorOfVariables, Polyhedra.PolyhedraOptSet{Float64, DefaultPolyhedron{Float64, MixedMatHRep{Float64, Matrix{Float64}}, MixedMatVRep{Float64, Matrix{Float64}}}}}, f::MathOptInterface.Bridges.var"#55#56"{MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, MathOptInterface.ConstraintConflictStatus})
    @ MathOptInterface.Bridges ~/.julia/packages/MathOptInterface/YDdD3/src/Bridges/bridge_optimizer.jl:288
  [7] get(b::MathOptInterface.Bridges.LazyBridgeOptimizer{CPLEX.Optimizer}, attr::MathOptInterface.ConstraintConflictStatus, ci::MathOptInterface.ConstraintIndex{MathOptInterface.VectorOfVariables, Polyhedra.PolyhedraOptSet{Float64, DefaultPolyhedron{Float64, MixedMatHRep{Float64, Matrix{Float64}}, MixedMatVRep{Float64, Matrix{Float64}}}}})
    @ MathOptInterface.Bridges ~/.julia/packages/MathOptInterface/YDdD3/src/Bridges/bridge_optimizer.jl:1206
  [8] get(model::MathOptInterface.Utilities.CachingOptimizer{MathOptInterface.AbstractOptimizer, MathOptInterface.Utilities.UniversalFallback{MathOptInterface.Utilities.GenericModel{Float64, MathOptInterface.Utilities.ModelFunctionConstraints{Float64}}}}, attr::MathOptInterface.ConstraintConflictStatus, index::MathOptInterface.ConstraintIndex{MathOptInterface.VectorOfVariables, Polyhedra.PolyhedraOptSet{Float64, DefaultPolyhedron{Float64, MixedMatHRep{Float64, Matrix{Float64}}, MixedMatVRep{Float64, Matrix{Float64}}}}})
    @ MathOptInterface.Utilities ~/.julia/packages/MathOptInterface/YDdD3/src/Utilities/cachingoptimizer.jl:757
  [9] _moi_get_result(::MathOptInterface.Utilities.CachingOptimizer{MathOptInterface.AbstractOptimizer, MathOptInterface.Utilities.UniversalFallback{MathOptInterface.Utilities.GenericModel{Float64, MathOptInterface.Utilities.ModelFunctionConstraints{Float64}}}}, ::MathOptInterface.ConstraintConflictStatus, ::Vararg{Any, N} where N)
    @ JuMP ~/.julia/packages/JuMP/klrjG/src/JuMP.jl:1199
 [10] get(model::Model, attr::MathOptInterface.ConstraintConflictStatus, cr::ConstraintRef{Model, MathOptInterface.ConstraintIndex{MathOptInterface.VectorOfVariables, Polyhedra.PolyhedraOptSet{Float64, DefaultPolyhedron{Float64, MixedMatHRep{Float64, Matrix{Float64}}, MixedMatVRep{Float64, Matrix{Float64}}}}}, VectorShape})
    @ JuMP ~/.julia/packages/JuMP/klrjG/src/JuMP.jl:1244
 [11] top-level scope
    @ ./REPL[178]:3
 [12] top-level scope
    @ ~/.julia/packages/CUDA/Uurn4/src/initialization.jl:52

[odow]

Hi Chelsea, I'm going to close this issue and ask you to post on the community forum: https://discourse.julialang.org/c/domain/opt/13 with a reproducible example. (Two main reasons: this isn't a bug in MathOptInterface, and it may help others with similar questions in the future.)

But it looks like this is a missing feature of Polyhedra, not MathOptInterface. The conflict analysis is also pretty limited to simple LPs/MIPs. It probably won't work through more complicated JuMP extensions like Polyhedra.jl.