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

A power function constraint states that the relationship <span>$</span>y = x^a<span>$</span> should hold for variables <span>$</span>x<span>$</span> and <span>$</span>y<span>$</span>, where <span>$</span>a<span>$</span> is the (constant) exponent. The lower bound of variable <span>$</span>x<span>$</span> must be nonnegative, even if <span>$</span>a<span>$</span> is an integer, and <span>$</span>x > 0<span>$</span> if <span>$</span>a < 0<span>$</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, FuncPieceLength, and FuncPieceRatio. For details, consult the General Constraint discussion.

GRBGenConstr AddGenConstrPow ( GRBVar xvar,
    GRBVar yvar,
    double a,
    string name,
    string options )


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

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

a: The exponent of the function.

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.

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