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presol_dualagg.h File Reference Detailed Descriptionaggregate variables by dual arguments This presolver looks for variables which could not be handled by duality fixing because of one up/downlock. If the constraint which delivers the up/downlock has a specific structure, we can aggregate the corresponding variable. In more detail (for a minimization problem and the case of only one uplock): Given a variable x_i with c_i <= 0 and only one up lock (originating from a constraint c), we are looking for a binary variable x_j such that: 1) if x_j = 0, constraint c can only be fulfilled for x_i = lb_i, and 2) if x_j = 1, constraint c becomes redundant and x_i can be dualfixed to its upper bound ub_i (or vice versa). Then we can perform the following aggregation: x_i = lb_i + x_j (ub_i  lb_i). Similar arguments apply for the case of only one down lock and c_i >= 0. Definition in file presol_dualagg.h. #include "scip/scip.h" Go to the source code of this file.
Function Documentation
creates the dualagg presolver and includes it in SCIP
