GRBModel::addGenConstrLogistic()

Add a new general constraint of type GRB_GENCONSTR_LOGISTIC to a model.

A logistic function constraint states that the relationship $y = \frac{1}{1 + e^{-x}}$ should hold for variables $x$ and $y$.

A piecewise-linear approximation of the function is added to the model. The details of the approximation are controlled using the following four attributes (or using the parameters with the same names): FuncPieces, FuncPieceError, FuncPieceLength, and FuncPieceRatio. For details, consult the General Constraint discussion.

GRBGenConstr addGenConstrLogistic ( GRBVar xvar,
    GRBVar yvar,
    std::string name="",
    std::string options="" )

Arguments:

xvar: The $x$ variable.

yvar: The $y$ variable.

name (optional): Name for the new general constraint.

options (optional): A string that can be used to set the attributes that control the piecewise-linear approximation of this function constraint. To assign a value to an attribute, follow the attribute name with an equal sign and the desired value (with no spaces). Assignments for different attributes should be separated by spaces (e.g. "FuncPieces=-1 FuncPieceError=0.001").

Return value:

New general constraint.