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int GRBgetBasisHead ( GRBmodel *model,
    int *bhead )

Returns the indices of the variables that make up the current basis matrix.

Return value:

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


model: The model. Note that the model must have a current optimal basis, as computed by GRBoptimize.

bhead: The constraint matrix columns that make up the current basis. The result contains one entry per constraint in <span>$</span>A<span>$</span>. If bhead[i]=j, then column i in the basis matrix <span>$</span>B<span>$</span> is column j from the constraint matrix <span>$</span>A<span>$</span>. Note that the basis may contain slack or articifial variables. If bhead[i] is greater than or equal to cols (the number of columns in <span>$</span>A<span>$</span>), then the corresponding basis column is the articial or slack variable from row bhead[i]-cols.

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