Documentation


Model.addGenConstrAbs()

addGenConstrAbs ( resvar, argvar, name="" )

Add a new general constraint of type GRB.GENCONSTR_ABS to a model.

An ABS constraint <span>$</span>r = \mbox{abs}\{x\}<span>$</span> states that the resultant variable <span>$</span>r<span>$</span> should be equal to the absolute value of the argument variable <span>$</span>x<span>$</span>.

You can also add an ABS constraint using the abs_ function.

Arguments:

resvar (Var): The variable whose value will be to equal the absolute value of the argument variable.

argvar (Var): The variable for which the absolute value will be taken.

name (string, optional): Name for the new general 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.

Example usage:

  # x5 = abs(x1)
  model.addGenConstrAbs(x5, x1, "absconstr")

  # overloaded form
  model.addConstr(x5 == abs_(x1), name="absconstr")