1    	/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
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.         */
10   	/*  You may obtain a copy of the License at                                  */
11   	/*                                                                           */
12   	/*      http://www.apache.org/licenses/LICENSE-2.0                           */
13   	/*                                                                           */
14   	/*  Unless required by applicable law or agreed to in writing, software      */
15   	/*  distributed under the License is distributed on an "AS IS" BASIS,        */
16   	/*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
17   	/*  See the License for the specific language governing permissions and      */
18   	/*  limitations under the License.                                           */
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   boundstore.c
26   	 * @ingroup PARALLEL
27   	 * @brief  the implementation of the bound store datastructure
28   	 * @author Leona Gottwald
29   	 */
30   	
31   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
32   	
33   	#include "scip/boundstore.h"
34   	#include "scip/struct_syncstore.h"
35   	#include "blockmemshell/memory.h"
36   	#include "scip/scip.h"
37   	
38   	/** create bound store data structure */
39   	SCIP_RETCODE SCIPboundstoreCreate(
40   	   SCIP*                 scip,               /**< scip main datastructure */
41   	   SCIP_BOUNDSTORE**     boundstore,         /**< pointer to store the bound store datastructure */
42   	   int                   nvars               /**< number of variables for which bounds may be stored */
43   	   )
44   	{
45   	   assert(scip != NULL);
46   	   assert(boundstore != NULL);
47   	
48   	   SCIP_CALL( SCIPallocMemory(scip, boundstore) );
49   	
50   	   (*boundstore)->bndchg = NULL;
51   	   (*boundstore)->bndchgsize = 0;
52   	   (*boundstore)->nbndchg = 0;
53   	   (*boundstore)->nvars = nvars;
54   	   SCIP_CALL( SCIPallocClearBlockMemoryArray(scip, &(*boundstore)->bndpos, nvars) );
55   	
56   	   return SCIP_OKAY;
57   	}
58   	
59   	/** free bound store data structure */
60   	void SCIPboundstoreFree(
61   	   SCIP*                 scip,               /**< scip main datastructure */
62   	   SCIP_BOUNDSTORE**     boundstore          /**< pointer to the bound store datastructure */
63   	   )
64   	{
65   	   assert(scip != NULL);
66   	   assert(boundstore != NULL);
67   	   assert((*boundstore) != NULL);
68   	
69   	   SCIPfreeBlockMemoryArray(scip, &(*boundstore)->bndpos, (*boundstore)->nvars);
70   	   SCIPfreeBlockMemoryArrayNull(scip, &(*boundstore)->bndchg, (*boundstore)->bndchgsize);
71   	   SCIPfreeMemory(scip, boundstore);
72   	}
73   	
74   	/** add bound change to bound store data structure */
75   	SCIP_RETCODE SCIPboundstoreAdd(
76   	   SCIP*                 scip,               /**< scip main datastructure */
77   	   SCIP_BOUNDSTORE*      boundstore,         /**< the bound store datastructure */
78   	   int                   varidx,             /**< variable index of bound change, must be smaller than the
79   	                                              *   number of variables given during creation of bound store */
80   	   SCIP_Real             newbound,           /**< bound value of variable */
81   	   SCIP_BOUNDTYPE        boundtype           /**< type of new bound */
82   	   )
83   	{
84   	   /* check if already stored a bound of same type for this variable */
85   	   int pos;
86   	
87   	   assert(scip != NULL);
88   	   assert(boundstore != NULL);
89   	
90   	   pos = boundstore->bndpos[varidx].pos[boundtype];
91   	
92   	   if( pos == 0 )
93   	   {
94   	      /* variable has no bound stored yet so store this bound */
95   	      int i;
96   	      i = boundstore->nbndchg++;
97   	      SCIP_CALL( SCIPensureBlockMemoryArray(scip, &boundstore->bndchg, &boundstore->bndchgsize, boundstore->nbndchg) );
98   	      boundstore->bndchg[i].varidx = varidx;
99   	      boundstore->bndchg[i].newbound = newbound;
100  	      boundstore->bndchg[i].boundtype = boundtype;
101  	      boundstore->bndpos[varidx].pos[boundtype] = boundstore->nbndchg;
102  	   }
103  	   else
104  	   {
105  	      /* since pos == 0 is reserved if no bound is stored
106  	       * the index is pos-1
107  	       */
108  	      --pos;
109  	      assert(boundstore->bndchg[pos].boundtype == boundtype);
110  	      assert(boundstore->bndchg[pos].varidx == varidx);
111  	
112  	      /* if the bound is better overwrite the old one */
113  	      if( (boundtype == SCIP_BOUNDTYPE_LOWER && newbound > boundstore->bndchg[pos].newbound) ||
114  	          (boundtype == SCIP_BOUNDTYPE_UPPER && newbound < boundstore->bndchg[pos].newbound) )
115  	      {
116  	         boundstore->bndchg[pos].newbound = newbound;
117  	      }
118  	   }
119  	
120  	   return SCIP_OKAY;
121  	}
122  	
123  	/** add all bound changes of source to target */
124  	SCIP_RETCODE SCIPboundstoreMerge(
125  	   SCIP*                 scip,               /**< scip main datastructure for target boundstore */
126  	   SCIP_BOUNDSTORE*      target,             /**< the bound store datastructure where the bounds get merged in */
127  	   SCIP_BOUNDSTORE*      source              /**< the bound store datastructure from which the bounds get merged in */
128  	   )
129  	{
130  	   int i;
131  	
132  	   assert(scip != NULL);
133  	   assert(source != NULL);
134  	   assert(target != NULL);
135  	
136  	   /* just iterate over the boundchanges in the source and add them to the target */
137  	   for( i = 0; i < source->nbndchg; ++i )
138  	   {
139  	      SCIP_CALL( SCIPboundstoreAdd(scip, target, source->bndchg[i].varidx, source->bndchg[i].newbound, source->bndchg[i].boundtype) );
140  	   }
141  	
142  	   return SCIP_OKAY;
143  	}
144  	
145  	/** remove all boundchanges from bound store */
146  	void SCIPboundstoreClear(
147  	   SCIP_BOUNDSTORE*      boundstore          /**< the bound store datastructure */
148  	   )
149  	{
150  	   assert(boundstore != NULL);
151  	
152  	   /* clearing the positions is enough */
153  	   if( boundstore->nbndchg > 0 )
154  	   {
155  	      BMSclearMemoryArray(boundstore->bndpos, boundstore->nvars);
156  	      boundstore->nbndchg = 0;
157  	   }
158  	}
159  	
160  	/** gets variable index of the i'th stored boundchange */
161  	int SCIPboundstoreGetChgVaridx(
162  	   SCIP_BOUNDSTORE*      boundstore,         /**< the bound store datastructure */
163  	   int                   i                   /**< the index of the bound change */
164  	   )
165  	{
166  	   assert(boundstore != NULL);
167  	   assert(i < boundstore->nbndchg);
168  	
169  	   return boundstore->bndchg[i].varidx;
170  	}
171  	
172  	/** gets the type of the i'th stored boundchange */
173  	SCIP_BOUNDTYPE SCIPboundstoreGetChgType(
174  	   SCIP_BOUNDSTORE*      boundstore,         /**< the bound store datastructure */
175  	   int                   i                   /**< the index of the bound change */
176  	   )
177  	{
178  	   assert(boundstore != NULL);
179  	   assert(i < boundstore->nbndchg);
180  	
181  	   return boundstore->bndchg[i].boundtype;
182  	}
183  	
184  	/** gets the bound value of the i'th stored boundchange */
185  	SCIP_Real SCIPboundstoreGetChgVal(
186  	   SCIP_BOUNDSTORE*      boundstore,         /**< the bound store datastructure */
187  	   int                   i                   /**< the index of the bound change */
188  	   )
189  	{
190  	   assert(boundstore != NULL);
191  	   assert(i < boundstore->nbndchg);
192  	
193  	   return boundstore->bndchg[i].newbound;
194  	}
195  	
196  	/** gets the number of stored bound changes */
197  	int SCIPboundstoreGetNChgs(
198  	   SCIP_BOUNDSTORE*      boundstore          /**< the bound store datastructure */
199  	   )
200  	{
201  	   assert(boundstore != NULL);
202  	
203  	   return boundstore->nbndchg;
204  	}
205