Scippy

SCIP

Solving Constraint Integer Programs

type_lpi.h File Reference

Detailed Description

type definitions for specific LP solvers interface

Author
Tobias Achterberg

Definition in file type_lpi.h.

Go to the source code of this file.

Typedefs

typedef enum SCIP_ObjSen SCIP_OBJSEN
 
typedef enum SCIP_LPParam SCIP_LPPARAM
 
typedef enum SCIP_Pricing SCIP_PRICING
 
typedef enum SCIP_BaseStat SCIP_BASESTAT
 
typedef enum SCIP_LPSolQuality SCIP_LPSOLQUALITY
 
typedef struct SCIP_LPi SCIP_LPI
 
typedef struct SCIP_LPiState SCIP_LPISTATE
 
typedef struct SCIP_LPiNorms SCIP_LPINORMS
 

Enumerations

enum  SCIP_ObjSen {
  SCIP_OBJSEN_MAXIMIZE = -1 ,
  SCIP_OBJSEN_MINIMIZE = +1
}
 
enum  SCIP_LPParam {
  SCIP_LPPAR_FROMSCRATCH = 0 ,
  SCIP_LPPAR_FASTMIP = 1 ,
  SCIP_LPPAR_SCALING = 2 ,
  SCIP_LPPAR_PRESOLVING = 3 ,
  SCIP_LPPAR_PRICING = 4 ,
  SCIP_LPPAR_LPINFO = 5 ,
  SCIP_LPPAR_FEASTOL = 6 ,
  SCIP_LPPAR_DUALFEASTOL = 7 ,
  SCIP_LPPAR_BARRIERCONVTOL = 8 ,
  SCIP_LPPAR_OBJLIM = 9 ,
  SCIP_LPPAR_LPITLIM = 10 ,
  SCIP_LPPAR_LPTILIM = 11 ,
  SCIP_LPPAR_MARKOWITZ = 12 ,
  SCIP_LPPAR_ROWREPSWITCH = 13 ,
  SCIP_LPPAR_THREADS = 14 ,
  SCIP_LPPAR_CONDITIONLIMIT = 15 ,
  SCIP_LPPAR_TIMING = 16 ,
  SCIP_LPPAR_RANDOMSEED = 17 ,
  SCIP_LPPAR_POLISHING = 18 ,
  SCIP_LPPAR_REFACTOR = 19
}
 
enum  SCIP_Pricing {
  SCIP_PRICING_LPIDEFAULT = 0 ,
  SCIP_PRICING_AUTO = 1 ,
  SCIP_PRICING_FULL = 2 ,
  SCIP_PRICING_PARTIAL = 3 ,
  SCIP_PRICING_STEEP = 4 ,
  SCIP_PRICING_STEEPQSTART = 5 ,
  SCIP_PRICING_DEVEX = 6
}
 
enum  SCIP_BaseStat {
  SCIP_BASESTAT_LOWER = 0 ,
  SCIP_BASESTAT_BASIC = 1 ,
  SCIP_BASESTAT_UPPER = 2 ,
  SCIP_BASESTAT_ZERO = 3
}
 
enum  SCIP_LPSolQuality {
  SCIP_LPSOLQUALITY_ESTIMCONDITION = 0 ,
  SCIP_LPSOLQUALITY_EXACTCONDITION = 1
}
 

Typedef Documentation

◆ SCIP_OBJSEN

typedef enum SCIP_ObjSen SCIP_OBJSEN

Definition at line 45 of file type_lpi.h.

◆ SCIP_LPPARAM

typedef enum SCIP_LPParam SCIP_LPPARAM

Definition at line 73 of file type_lpi.h.

◆ SCIP_PRICING

typedef enum SCIP_Pricing SCIP_PRICING

Definition at line 86 of file type_lpi.h.

◆ SCIP_BASESTAT

Definition at line 96 of file type_lpi.h.

◆ SCIP_LPSOLQUALITY

Definition at line 104 of file type_lpi.h.

◆ SCIP_LPI

typedef struct SCIP_LPi SCIP_LPI

solver dependent LP interface

Definition at line 106 of file type_lpi.h.

◆ SCIP_LPISTATE

typedef struct SCIP_LPiState SCIP_LPISTATE

complete LP state (i.e. basis information)

Definition at line 107 of file type_lpi.h.

◆ SCIP_LPINORMS

typedef struct SCIP_LPiNorms SCIP_LPINORMS

LP pricing norms information

Definition at line 108 of file type_lpi.h.

Enumeration Type Documentation

◆ SCIP_ObjSen

objective sense

Enumerator
SCIP_OBJSEN_MAXIMIZE 

maximize objective function

SCIP_OBJSEN_MINIMIZE 

minimize objective function

Definition at line 40 of file type_lpi.h.

◆ SCIP_LPParam

LP solver parameters

Enumerator
SCIP_LPPAR_FROMSCRATCH 

solver should start from scratch at next call?

SCIP_LPPAR_FASTMIP 

fast mip setting of LP solver

SCIP_LPPAR_SCALING 

should LP solver use scaling?

SCIP_LPPAR_PRESOLVING 

should LP solver use presolving?

SCIP_LPPAR_PRICING 

pricing strategy

SCIP_LPPAR_LPINFO 

should LP solver output information to the screen?

SCIP_LPPAR_FEASTOL 

feasibility tolerance for primal variables and slacks, strictly positive

SCIP_LPPAR_DUALFEASTOL 

feasibility tolerance for dual variables and reduced costs, strictly positive

SCIP_LPPAR_BARRIERCONVTOL 

convergence tolerance used in barrier algorithm

SCIP_LPPAR_OBJLIM 

objective limit (stop if objective is known be larger/smaller than limit for min/max-imization)

SCIP_LPPAR_LPITLIM 

LP iteration limit, greater than or equal 0

SCIP_LPPAR_LPTILIM 

LP time limit, positive

SCIP_LPPAR_MARKOWITZ 

Markowitz tolerance

SCIP_LPPAR_ROWREPSWITCH 

simplex algorithm shall use row representation of the basis if number of rows divided by number of columns exceeds this value (0 <= value or -1 = valu ; if negative, this change never occurs)

SCIP_LPPAR_THREADS 

number of threads used to solve the LP

SCIP_LPPAR_CONDITIONLIMIT 

maximum condition number of LP basis counted as stable

SCIP_LPPAR_TIMING 

type of timer (1 - cpu, 2 - wallclock, 0 - off)

SCIP_LPPAR_RANDOMSEED 

inital random seed, e.g. for perturbations in the simplex (0: LP default)

SCIP_LPPAR_POLISHING 

set solution polishing (0 - disable, 1 - enable)

SCIP_LPPAR_REFACTOR 

set refactorization interval (0 - automatic)

Definition at line 48 of file type_lpi.h.

◆ SCIP_Pricing

LP pricing strategy

Enumerator
SCIP_PRICING_LPIDEFAULT 

the SCIP/LP interface should use its preferred strategy

SCIP_PRICING_AUTO 

the LP solver should use its preferred strategy

SCIP_PRICING_FULL 

full pricing

SCIP_PRICING_PARTIAL 

partial pricing

SCIP_PRICING_STEEP 

steepest edge pricing

SCIP_PRICING_STEEPQSTART 

steepest edge pricing without initial dual norms

SCIP_PRICING_DEVEX 

devex pricing

Definition at line 76 of file type_lpi.h.

◆ SCIP_BaseStat

basis status for columns and rows

Enumerator
SCIP_BASESTAT_LOWER 

(slack) variable is at its lower bound

SCIP_BASESTAT_BASIC 

(slack) variable is basic

SCIP_BASESTAT_UPPER 

(slack) variable is at its upper bound

SCIP_BASESTAT_ZERO 

free variable is non-basic and set to zero

Definition at line 89 of file type_lpi.h.

◆ SCIP_LPSolQuality

LP solution quality quantities

Enumerator
SCIP_LPSOLQUALITY_ESTIMCONDITION 

estimated condition number of (scaled) basis matrix (SCIP_Real)

SCIP_LPSOLQUALITY_EXACTCONDITION 

exact condition number of (scaled) basis matrix (SCIP_Real)

Definition at line 99 of file type_lpi.h.