GRBModel.AddGenConstrLog()

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

A natural logarithmic function constraint states that the relationship <span>$</span>y = log(x)<span>$</span> should hold for variables <span>$</span>x<span>$</span> and <span>$</span>y<span>$</span>.

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, FuncPiecesLength, and FuncPieceRatio. For details, consult the General Constraint discussion.

GRBGenConstr AddGenConstrLog ( GRBVar xvar,
    GRBVar yvar,
    string name,
    string options )

Arguments:

xvar: The <span>$</span>x<span>$</span> variable.

yvar: The <span>$</span>y<span>$</span> variable.

name: Name for the new general constraint.

options: 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.