1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* */
/* This file is part of the program and library */
/* SCIP --- Solving Constraint Integer Programs */
/* */
/* Copyright 2002-2022 Zuse Institute Berlin */
/* */
/* Licensed under the Apache License, Version 2.0 (the "License"); */
/* you may not use this file except in compliance with the License. */
/* You may obtain a copy of the License at */
/* */
/* http://www.apache.org/licenses/LICENSE-2.0 */
/* */
/* Unless required by applicable law or agreed to in writing, software */
/* distributed under the License is distributed on an "AS IS" BASIS, */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
/* See the License for the specific language governing permissions and */
/* limitations under the License. */
/* */
/* You should have received a copy of the Apache-2.0 license */
/* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
/* */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/**@file sepa_mcf.h
* @ingroup SEPARATORS
* @brief multi-commodity-flow network cut separator
* @author Tobias Achterberg
* @author Christian Raack
*
* We try to identify a multi-commodity flow structure in the LP relaxation of the
* following type:
*
* (1) sum_{a in delta^+(v)} f_a^k - sum_{a in delta^-(v)} f_a^k <= -d_v^k for all v in V and k in K
* (2) sum_{k in K} f_a^k - c_a x_a <= 0 for all a in A
*
* Constraints (1) are flow conservation constraints, which say that for each commodity k and node v the
* outflow (delta^+(v)) minus the inflow (delta^-(v)) of a node v must not exceed the negative of the demand of
* node v in commodity k. To say it the other way around, inflow minus outflow must be at least equal to the demand.
* Constraints (2) are the arc capacity constraints, which say that the sum of all flow over an arc a must not
* exceed its capacity c_a x_a, with x being a binary or integer variable.
* c_a x_a does not need to be a single product of a capacity and an integer variable; we also accept general scalar
* products.
*/
/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
#ifndef __SCIP_SEPA_MCF_H__
#define __SCIP_SEPA_MCF_H__
#include "scip/def.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
#ifdef __cplusplus
extern "C" {
#endif
/** creates the mcf separator and includes it in SCIP
*
* @ingroup SeparatorIncludes
*/
SCIP_EXPORT
SCIP_RETCODE SCIPincludeSepaMcf(
SCIP* scip /**< SCIP data structure */
);
#ifdef __cplusplus
}
#endif
#endif