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addQConstr ( lhs, sense=None, rhs=None, name="" )

Add a quadratic constraint to a model.

Important note: Gurobi can handle both convex and non-convex quadratic constraints. The differences between them can be both important and subtle. Refer to this discussion for additional information.


lhs: Left-hand side for new quadratic constraint. Can be a constant, a Var, a LinExpr, or a QuadExpr.

sense: Sense for new quadratic constraint (GRB.LESS_EQUAL or GRB.GREATER_EQUAL).

rhs: Right-hand side for new quadratic constraint. Can be a constant, a Var, a LinExpr, or a QuadExpr.

name: Name for new constraint. Note that name will be stored as an ASCII string. Thus, a name like 'A<span>$</span>{\rightarrow}<span>$</span>B' will produce an error, because '<span>$</span>{\rightarrow}<span>$</span>' can not be represented as an ASCII character. Note also that names that contain spaces are strongly discouraged, because they can't be written to LP format files.

Return value:

New quadratic constraint object.

Example usage:

  model.addQConstr(x*x + y*y, GRB.LESS_EQUAL, z*z, "c0")
  model.addQConstr(x*x + y*y <= 2.0, "c1")

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