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2    	/*                                                                           */
3    	/*                  This file is part of the program and library             */
4    	/*         SCIP --- Solving Constraint Integer Programs                      */
5    	/*                                                                           */
6    	/*  Copyright (c) 2002-2023 Zuse Institute Berlin (ZIB)                      */
7    	/*                                                                           */
8    	/*  Licensed under the Apache License, Version 2.0 (the "License");          */
9    	/*  you may not use this file except in compliance with the License.         */
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11   	/*                                                                           */
12   	/*      http://www.apache.org/licenses/LICENSE-2.0                           */
13   	/*                                                                           */
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15   	/*  distributed under the License is distributed on an "AS IS" BASIS,        */
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19   	/*                                                                           */
20   	/*  You should have received a copy of the Apache-2.0 license                */
21   	/*  along with SCIP; see the file LICENSE. If not visit scipopt.org.         */
22   	/*                                                                           */
23   	/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24   	
25   	/**@file   heur_rounding.h
26   	 * @ingroup PRIMALHEURISTICS
27   	 * @brief  LP rounding heuristic that tries to recover from intermediate infeasibilities
28   	 * @author Tobias Achterberg
29   	 *
30   	 * Rounding heuristic that starts from an LP-feasible point and reduces the number of fractional variables by one in
31   	 * each step. As long as no LP row is violated, the algorithm iterates over the fractional variables and applies a
32   	 * rounding into the direction of fewer locks, updating the activities of the LP rows after each step.  If there is a
33   	 * violated LP row, the heuristic will try to find a fractional variable that can be rounded in a direction such that
34   	 * the violation of the constraint is decreased, using the number of up- and down-locks as a tie breaker.  If no
35   	 * rounding can decrease the violation of the constraint, the procedure is aborted.
36   	 */
37   	
38   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
39   	
40   	#ifndef __SCIP_HEUR_ROUNDING_H__
41   	#define __SCIP_HEUR_ROUNDING_H__
42   	
43   	#include "scip/def.h"
44   	#include "scip/type_retcode.h"
45   	#include "scip/type_scip.h"
46   	
47   	#ifdef __cplusplus
48   	extern "C" {
49   	#endif
50   	
51   	/** creates the rounding heuristic with infeasibility recovering and includes it in SCIP
52   	 *
53   	 *  @ingroup PrimalHeuristicIncludes
54   	 */
55   	SCIP_EXPORT
56   	SCIP_RETCODE SCIPincludeHeurRounding(
57   	   SCIP*                 scip                /**< SCIP data structure */
58   	   );
59   	
60   	#ifdef __cplusplus
61   	}
62   	#endif
63   	
64   	#endif
65