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addConstr ( constr, name="" )

Add a constraint to a model.

This method accepts a TempConstr as its first argument, and the constraint name as its optional second argument. You use operator overloading to create the argument (see this section for details). This one method allows you to add linear constraints, matrix constraints, quadratic constraints, and general constraints.


constr: TempConstr argument.

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 constraint object. This can be a Constr, an MConstr, or a QConstr, or a MQConstr, depending on the type of the argument.

Example usage:

  model.addConstr(x + y <= 2.0, "c1")
  model.addConstr(x*x + y*y <= 4.0, "qc0")
  model.addConstr(x + y + z == [1, 2], "rgc0")
  model.addConstr(A @ t >= b)
  model.addConstr(z == and_(x, y, w), "gc0")
  model.addConstr(z == min_(x, y), "gc1")
  model.addConstr((w == 1) >> (x + y <= 1), "ic0")

A constraint can only have a single comparison operator. While 1 <= x + y <= 2 may look like a valid constraint, addConstr won't accept it.

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