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heur_actconsdiving.h
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18 * @brief LP diving heuristic that chooses fixings w.r.t. the active constraints the variable appear in
21 * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
22 * depth-first-search in the tree. Active Constraint Diving chooses a variable based on the active LP rows (equations
23 * are counted twice here). The variable score is calculated as a convex combination of the number of constraints the
24 * variable appears in, the sum of all positive coefficients and the absolute sum of all negative coefficients. The
25 * chosen variable is then rounded to the closest integer. One-level backtracking is applied: If the LP gets infeasible,
26 * the last fixings is undone, and the opposite fixing is tried. If this is infeasible, too, the procedure aborts.
29 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
SCIP_RETCODE SCIPincludeHeurActconsdiving(SCIP *scip) SCIP callable library. |