Scippy

SCIP

Solving Constraint Integer Programs

type_lpi.h
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1/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2/* */
3/* This file is part of the program and library */
4/* SCIP --- Solving Constraint Integer Programs */
5/* */
6/* Copyright (c) 2002-2024 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 */
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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, */
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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 type_lpi.h
26 * @brief type definitions for specific LP solvers interface
27 * @author Tobias Achterberg
28 */
29
30/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
31
32#ifndef __SCIP_TYPE_LPI_H__
33#define __SCIP_TYPE_LPI_H__
34
35#ifdef __cplusplus
36extern "C" {
37#endif
38
39/** objective sense */
41{
42 SCIP_OBJSEN_MAXIMIZE = -1, /**< maximize objective function */
43 SCIP_OBJSEN_MINIMIZE = +1 /**< minimize objective function */
44};
46
47/** LP solver parameters */
49{
50 SCIP_LPPAR_FROMSCRATCH = 0, /**< solver should start from scratch at next call? */
51 SCIP_LPPAR_FASTMIP = 1, /**< fast mip setting of LP solver */
52 SCIP_LPPAR_SCALING = 2, /**< should LP solver use scaling? */
53 SCIP_LPPAR_PRESOLVING = 3, /**< should LP solver use presolving? */
54 SCIP_LPPAR_PRICING = 4, /**< pricing strategy */
55 SCIP_LPPAR_LPINFO = 5, /**< should LP solver output information to the screen? */
56 SCIP_LPPAR_FEASTOL = 6, /**< feasibility tolerance for primal variables and slacks, strictly positive */
57 SCIP_LPPAR_DUALFEASTOL = 7, /**< feasibility tolerance for dual variables and reduced costs, strictly positive */
58 SCIP_LPPAR_BARRIERCONVTOL = 8, /**< convergence tolerance used in barrier algorithm */
59 SCIP_LPPAR_OBJLIM = 9, /**< objective limit (stop if objective is known be larger/smaller than limit for min/max-imization) */
60 SCIP_LPPAR_LPITLIM = 10, /**< LP iteration limit, greater than or equal 0 */
61 SCIP_LPPAR_LPTILIM = 11, /**< LP time limit, positive */
62 SCIP_LPPAR_MARKOWITZ = 12, /**< Markowitz tolerance */
63 SCIP_LPPAR_ROWREPSWITCH = 13, /**< simplex algorithm shall use row representation of the basis
64 * if number of rows divided by number of columns exceeds this value
65 * (0 <= value or -1 = valu ; if negative, this change never occurs) */
66 SCIP_LPPAR_THREADS = 14, /**< number of threads used to solve the LP */
67 SCIP_LPPAR_CONDITIONLIMIT = 15, /**< maximum condition number of LP basis counted as stable */
68 SCIP_LPPAR_TIMING = 16, /**< type of timer (1 - cpu, 2 - wallclock, 0 - off) */
69 SCIP_LPPAR_RANDOMSEED = 17, /**< inital random seed, e.g. for perturbations in the simplex (0: LP default) */
70 SCIP_LPPAR_POLISHING = 18, /**< set solution polishing (0 - disable, 1 - enable) */
71 SCIP_LPPAR_REFACTOR = 19 /**< set refactorization interval (0 - automatic) */
72};
74
75/** LP pricing strategy */
77{
78 SCIP_PRICING_LPIDEFAULT = 0, /**< the SCIP/LP interface should use its preferred strategy */
79 SCIP_PRICING_AUTO = 1, /**< the LP solver should use its preferred strategy */
80 SCIP_PRICING_FULL = 2, /**< full pricing */
81 SCIP_PRICING_PARTIAL = 3, /**< partial pricing */
82 SCIP_PRICING_STEEP = 4, /**< steepest edge pricing */
83 SCIP_PRICING_STEEPQSTART = 5, /**< steepest edge pricing without initial dual norms */
84 SCIP_PRICING_DEVEX = 6 /**< devex pricing */
85};
87
88/** basis status for columns and rows */
90{
91 SCIP_BASESTAT_LOWER = 0, /**< (slack) variable is at its lower bound */
92 SCIP_BASESTAT_BASIC = 1, /**< (slack) variable is basic */
93 SCIP_BASESTAT_UPPER = 2, /**< (slack) variable is at its upper bound */
94 SCIP_BASESTAT_ZERO = 3 /**< free variable is non-basic and set to zero */
95};
97
98/** LP solution quality quantities */
100{
101 SCIP_LPSOLQUALITY_ESTIMCONDITION = 0, /**< estimated condition number of (scaled) basis matrix (SCIP_Real) */
102 SCIP_LPSOLQUALITY_EXACTCONDITION = 1 /**< exact condition number of (scaled) basis matrix (SCIP_Real) */
105
106typedef struct SCIP_LPi SCIP_LPI; /**< solver dependent LP interface */
107typedef struct SCIP_LPiState SCIP_LPISTATE; /**< complete LP state (i.e. basis information) */
108typedef struct SCIP_LPiNorms SCIP_LPINORMS; /**< LP pricing norms information */
109
110#ifdef __cplusplus
111}
112#endif
113
114#endif
SCIP_Pricing
Definition: type_lpi.h:77
@ SCIP_PRICING_STEEPQSTART
Definition: type_lpi.h:83
@ SCIP_PRICING_AUTO
Definition: type_lpi.h:79
@ SCIP_PRICING_DEVEX
Definition: type_lpi.h:84
@ SCIP_PRICING_STEEP
Definition: type_lpi.h:82
@ SCIP_PRICING_FULL
Definition: type_lpi.h:80
@ SCIP_PRICING_LPIDEFAULT
Definition: type_lpi.h:78
@ SCIP_PRICING_PARTIAL
Definition: type_lpi.h:81
enum SCIP_Pricing SCIP_PRICING
Definition: type_lpi.h:86
enum SCIP_LPParam SCIP_LPPARAM
Definition: type_lpi.h:73
SCIP_LPSolQuality
Definition: type_lpi.h:100
@ SCIP_LPSOLQUALITY_EXACTCONDITION
Definition: type_lpi.h:102
@ SCIP_LPSOLQUALITY_ESTIMCONDITION
Definition: type_lpi.h:101
SCIP_LPParam
Definition: type_lpi.h:49
@ SCIP_LPPAR_PRICING
Definition: type_lpi.h:54
@ SCIP_LPPAR_REFACTOR
Definition: type_lpi.h:71
@ SCIP_LPPAR_THREADS
Definition: type_lpi.h:66
@ SCIP_LPPAR_LPINFO
Definition: type_lpi.h:55
@ SCIP_LPPAR_POLISHING
Definition: type_lpi.h:70
@ SCIP_LPPAR_SCALING
Definition: type_lpi.h:52
@ SCIP_LPPAR_TIMING
Definition: type_lpi.h:68
@ SCIP_LPPAR_LPTILIM
Definition: type_lpi.h:61
@ SCIP_LPPAR_BARRIERCONVTOL
Definition: type_lpi.h:58
@ SCIP_LPPAR_PRESOLVING
Definition: type_lpi.h:53
@ SCIP_LPPAR_CONDITIONLIMIT
Definition: type_lpi.h:67
@ SCIP_LPPAR_RANDOMSEED
Definition: type_lpi.h:69
@ SCIP_LPPAR_FASTMIP
Definition: type_lpi.h:51
@ SCIP_LPPAR_DUALFEASTOL
Definition: type_lpi.h:57
@ SCIP_LPPAR_FROMSCRATCH
Definition: type_lpi.h:50
@ SCIP_LPPAR_MARKOWITZ
Definition: type_lpi.h:62
@ SCIP_LPPAR_FEASTOL
Definition: type_lpi.h:56
@ SCIP_LPPAR_LPITLIM
Definition: type_lpi.h:60
@ SCIP_LPPAR_ROWREPSWITCH
Definition: type_lpi.h:63
@ SCIP_LPPAR_OBJLIM
Definition: type_lpi.h:59
SCIP_BaseStat
Definition: type_lpi.h:90
@ SCIP_BASESTAT_BASIC
Definition: type_lpi.h:92
@ SCIP_BASESTAT_UPPER
Definition: type_lpi.h:93
@ SCIP_BASESTAT_LOWER
Definition: type_lpi.h:91
@ SCIP_BASESTAT_ZERO
Definition: type_lpi.h:94
enum SCIP_LPSolQuality SCIP_LPSOLQUALITY
Definition: type_lpi.h:104
SCIP_ObjSen
Definition: type_lpi.h:41
@ SCIP_OBJSEN_MAXIMIZE
Definition: type_lpi.h:42
@ SCIP_OBJSEN_MINIMIZE
Definition: type_lpi.h:43
enum SCIP_ObjSen SCIP_OBJSEN
Definition: type_lpi.h:45
enum SCIP_BaseStat SCIP_BASESTAT
Definition: type_lpi.h:96