Class: Cbc::ConflictSolver

Inherits:
Object
  • Object
show all
Defined in:
lib/ruby-cbc/conflict_solver.rb

Instance Method Summary collapse

Constructor Details

#initialize(model) ⇒ ConflictSolver

Returns a new instance of ConflictSolver.



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# File 'lib/ruby-cbc/conflict_solver.rb', line 5

def initialize(model)
 @model = model
end

Instance Method Details

#find_conflict ⇒ Object

Assuming there is a conflict



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# File 'lib/ruby-cbc/conflict_solver.rb', line 10

def find_conflict
  continuous = is_continuous_conflict?
  conflict_set = []
  all_constraints = @model.constraints.to_a
  nb_constraints = all_constraints.count
  loop do
    m = Model.new
    m.vars = @model.vars
    m.enforce(conflict_set)
    return conflict_set if infeasible?(m, continuous: continuous)

    constraint_idx = first_failing(conflict_set, all_constraints, nb_constraints, continuous: continuous)
    return conflict_set if !constraint_idx

    nb_constraints = constraint_idx
    conflict_set << all_constraints[constraint_idx]
  end
end

#is_continuous_conflict? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ruby-cbc/conflict_solver.rb', line 29

def is_continuous_conflict?
  # Same model without objective
  model = Model.new
  model.vars = @model.vars
  model.constraints = @model.constraints
  infeasible?(model, continuous: true)
end