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Diffstat (limited to 'build/Bonmin/include/coin/CoinPresolveZeros.hpp')
-rw-r--r-- | build/Bonmin/include/coin/CoinPresolveZeros.hpp | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/build/Bonmin/include/coin/CoinPresolveZeros.hpp b/build/Bonmin/include/coin/CoinPresolveZeros.hpp new file mode 100644 index 0000000..219e613 --- /dev/null +++ b/build/Bonmin/include/coin/CoinPresolveZeros.hpp @@ -0,0 +1,60 @@ +/* $Id: CoinPresolveZeros.hpp 1498 2011-11-02 15:25:35Z mjs $ */ +// Copyright (C) 2002, International Business Machines +// Corporation and others. All Rights Reserved. +// This code is licensed under the terms of the Eclipse Public License (EPL). + +#ifndef CoinPresolveZeros_H +#define CoinPresolveZeros_H + +/*! \file + + Drop/reintroduce explicit zeros. +*/ + +#define DROP_ZERO 8 + +/*! \brief Tracking information for an explicit zero coefficient + + \todo Why isn't this a nested class in drop_zero_coefficients_action? + That would match the structure of other presolve classes. +*/ + +struct dropped_zero { + int row; + int col; +}; + +/*! \brief Removal of explicit zeros + + The presolve action for this class removes explicit zeros from the constraint + matrix. The postsolve action puts them back. +*/ +class drop_zero_coefficients_action : public CoinPresolveAction { + + const int nzeros_; + const dropped_zero *const zeros_; + + drop_zero_coefficients_action(int nzeros, + const dropped_zero *zeros, + const CoinPresolveAction *next) : + CoinPresolveAction(next), + nzeros_(nzeros), zeros_(zeros) +{} + + public: + const char *name() const { return ("drop_zero_coefficients_action"); } + + static const CoinPresolveAction *presolve(CoinPresolveMatrix *prob, + int *checkcols, + int ncheckcols, + const CoinPresolveAction *next); + + void postsolve(CoinPostsolveMatrix *prob) const; + + virtual ~drop_zero_coefficients_action() { deleteAction(zeros_,dropped_zero*); } +}; + +const CoinPresolveAction *drop_zero_coefficients(CoinPresolveMatrix *prob, + const CoinPresolveAction *next); + +#endif |