heur_actconsdiving.h
Go to the documentation of this file.
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) Definition: objbranchrule.h:33 SCIP callable library. |