Documentation


GRBaddgenconstrMin

int GRBaddgenconstrMin ( GRBmodel *model,
    const char *name,
    int resvar,
    int nvars,
    int* vars,
    double constant )

Add a new general constraint of type GRB_GENCONSTR_MIN to a model. Note that, due to our lazy update approach, the new constraint won't actually be added until you update the model (using GRBupdatemodel), optimize the model (using GRBoptimize), or write the model to disk (using GRBwrite).

A MIN constraint <span>$</span>r = \min\{x_1,\ldots,x_n,c\}<span>$</span> states that the resultant variable <span>$</span>r<span>$</span> should be equal to the minimum of the operand variables <span>$</span>x_1,\ldots,x_n<span>$</span> and the constant <span>$</span>c<span>$</span>.

Return value:

A non-zero return value indicates that a problem occurred while adding the general constraint. Refer to the Error Code table for a list of possible return values. Details on the error can be obtained by calling GRBgeterrormsg.

Arguments:

model: The model to which the new general constraint should be added.

name: Name for the new general constraint. This argument can be NULL, in which case the constraint is given a default name.

int resvar: The index of the resultant variable <span>$</span>r<span>$</span> whose value will be equal to the min of the other variables.

int nvars: The number <span>$</span>n<span>$</span> of operand variables over which the min will be taken.

const int *vars: An array containing the indices of the operand variables <span>$</span>x_j<span>$</span> over which the min will be taken.

double constant: An additional operand that allows you to include a constant <span>$</span>c<span>$</span> among the arguments of the min operation.

Example usage:

  /* x5 = min(x1, x3, x4, 2.0) */
  int ind[] = {1, 3, 4};
  error = GRBaddgenconstrMin(model, "minconstr", 5,
                             3, ind, 2.0);