Detailed Description

DIFF file reader.

Author: Jakob Witzig

This reader allows to parse a new objective function in the style of CPLEX .lp files.

The lp format is defined within the CPLEX documentation.

An example of a *.diff file looks like this:

Minimize obj: - STM6 + STM7

Here is the objective sense set to minimize the function -STM6 + STM7.

Definition in file reader_diff.c.

#include <ctype.h>
#include "scip/pub_fileio.h"
#include "scip/pub_message.h"
#include "scip/pub_misc.h"
#include "scip/pub_reader.h"
#include "scip/pub_var.h"
#include "scip/reader_diff.h"
#include "scip/scip_general.h"
#include "scip/scip_mem.h"
#include "scip/scip_message.h"
#include "scip/scip_numerics.h"
#include "scip/scip_prob.h"
#include "scip/scip_reader.h"
#include "scip/scip_solve.h"
#include <stdlib.h>
#include <string.h>
#include <strings.h>

Go to the source code of this file.

Macros
#define	READER_NAME "diffreader"

#define	READER_DESC "file reader for changes in the LP file"

#define	READER_EXTENSION "diff"

#define	LP_MAX_LINELEN 65536

#define	LP_MAX_PUSHEDTOKENS 2

#define	LP_INIT_COEFSSIZE 8192

Typedefs
typedef enum LpSection	LPSECTION

typedef enum LpExpType	LPEXPTYPE

typedef enum LpSense	LPSENSE

typedef struct LpInput	LPINPUT

Enumerations
enum	LpSection { LP_START, LP_OBJECTIVE, LP_END, LP_START, LP_OBJECTIVE, LP_CONSTRAINTS, LP_BOUNDS, LP_GENERALS, LP_BINARIES, LP_SEMICONTINUOUS, LP_SOS, LP_END }

enum	LpExpType { LP_EXP_NONE, LP_EXP_UNSIGNED, LP_EXP_SIGNED, LP_EXP_NONE, LP_EXP_UNSIGNED, LP_EXP_SIGNED }

enum	LpSense { LP_SENSE_LE, LP_SENSE_GE, LP_SENSE_EQ, LP_SENSE_NOTHING, LP_SENSE_LE, LP_SENSE_GE, LP_SENSE_EQ }

Functions
static void	syntaxError (SCIP scip, LPINPUT lpinput, const char *msg)

static SCIP_Bool	hasError (LPINPUT *lpinput)

static SCIP_Bool	isDelimChar (char c)

static SCIP_Bool	isTokenChar (char c)

static SCIP_Bool	isValueChar (char c, char nextc, SCIP_Bool firstchar, SCIP_Bool hasdot, LPEXPTYPE exptype)

static SCIP_Bool	getNextLine (SCIP scip, LPINPUT lpinput)

static void	swapPointers (char pointer1, char pointer2)

static SCIP_Bool	getNextToken (SCIP scip, LPINPUT lpinput)

static void	pushToken (LPINPUT *lpinput)

static void	pushBufferToken (LPINPUT *lpinput)

static void	swapTokenBuffer (LPINPUT *lpinput)

static SCIP_Bool	isNewSection (SCIP scip, LPINPUT lpinput)

static SCIP_Bool	isSign (LPINPUT lpinput, int sign)

static SCIP_Bool	isValue (SCIP scip, LPINPUT lpinput, SCIP_Real *value)

static SCIP_Bool	isSense (LPINPUT lpinput, LPSENSE sense)

static SCIP_RETCODE	getVariable (SCIP scip, char name, SCIP_VAR **var)

static SCIP_RETCODE	readStart (SCIP scip, LPINPUT lpinput)

static SCIP_RETCODE	readCoefficients (SCIP scip, LPINPUT lpinput, SCIP_Bool isobjective, char name, int coefssize, SCIP_VAR *vars, SCIP_Real coefs, int ncoefs, SCIP_Bool newsection)

static SCIP_RETCODE	readObjective (SCIP scip, LPINPUT lpinput)

static SCIP_RETCODE	readDiffFile (SCIP scip, LPINPUT lpinput, const char *filename)

static	SCIP_DECL_READERCOPY (readerCopyDiff)

static	SCIP_DECL_READERFREE (readerFreeDiff)

static	SCIP_DECL_READERREAD (readerReadDiff)

SCIP_RETCODE	SCIPincludeReaderDiff (SCIP *scip)

SCIP_RETCODE	SCIPreadDiff (SCIP scip, SCIP_READER reader, const char filename, SCIP_RESULT result)

Variables
static const char	commentchars [] = "\\"

Macro Definition Documentation

◆ READER_NAME

#define READER_NAME "diffreader"

Definition at line 56 of file reader_diff.c.

Referenced by SCIP_DECL_READERCOPY(), and SCIPincludeReaderDiff().

◆ READER_DESC

#define READER_DESC "file reader for changes in the LP file"

Definition at line 57 of file reader_diff.c.

Referenced by SCIPincludeReaderDiff().

◆ READER_EXTENSION

#define READER_EXTENSION "diff"

Definition at line 58 of file reader_diff.c.

Referenced by SCIPincludeReaderDiff().

◆ LP_MAX_LINELEN

#define LP_MAX_LINELEN 65536

Definition at line 63 of file reader_diff.c.

Referenced by getNextLine(), getNextToken(), isNewSection(), readCoefficients(), readObjective(), and SCIPreadDiff().

◆ LP_MAX_PUSHEDTOKENS

#define LP_MAX_PUSHEDTOKENS 2

Definition at line 64 of file reader_diff.c.

Referenced by pushBufferToken(), pushToken(), and SCIPreadDiff().

◆ LP_INIT_COEFSSIZE

#define LP_INIT_COEFSSIZE 8192

Definition at line 65 of file reader_diff.c.

Referenced by readCoefficients().

Typedef Documentation

◆ LPSECTION

typedef enum LpSection LPSECTION

Definition at line 72 of file reader_diff.c.

◆ LPEXPTYPE

typedef enum LpExpType LPEXPTYPE

Definition at line 78 of file reader_diff.c.

◆ LPSENSE

typedef enum LpSense LPSENSE

Definition at line 84 of file reader_diff.c.

◆ LPINPUT

typedef struct LpInput LPINPUT

Definition at line 105 of file reader_diff.c.

Enumeration Type Documentation

◆ LpSection

enum LpSection

Section in LP File

Enumerator
LP_START
LP_OBJECTIVE
LP_END
LP_START
LP_OBJECTIVE
LP_CONSTRAINTS
LP_BOUNDS
LP_GENERALS
LP_BINARIES
LP_SEMICONTINUOUS
LP_SOS
LP_END

Definition at line 68 of file reader_diff.c.

◆ LpExpType

enum LpExpType

Enumerator
LP_EXP_NONE
LP_EXP_UNSIGNED
LP_EXP_SIGNED
LP_EXP_NONE
LP_EXP_UNSIGNED
LP_EXP_SIGNED

Definition at line 74 of file reader_diff.c.

◆ LpSense

enum LpSense

Enumerator
LP_SENSE_LE
LP_SENSE_GE
LP_SENSE_EQ
LP_SENSE_NOTHING
LP_SENSE_LE
LP_SENSE_GE
LP_SENSE_EQ

Definition at line 80 of file reader_diff.c.

Function Documentation

◆ syntaxError()

static void syntaxError	(	SCIP *	scip,
		LPINPUT *	lpinput,
		const char *	msg
	)

static

issues an error message and marks the LP data to have errors

Parameters

scip	SCIP data structure
lpinput	LP reading data
msg	error message

Definition at line 116 of file reader_diff.c.

References LP_END, NULL, SCIP_VERBLEVEL_MINIMAL, SCIPerrorMessage, SCIPsnprintf(), SCIPverbMessage(), and TRUE.

Referenced by readCoefficients().

◆ hasError()

static SCIP_Bool hasError ( LPINPUT * lpinput )

static

returns whether a syntax error was detected

Parameters

lpinput LP reading data

Definition at line 143 of file reader_diff.c.

References NULL.

Referenced by readDiffFile().

◆ isDelimChar()

static SCIP_Bool isDelimChar ( char c )

static

returns whether the given character is a token delimiter

Parameters

c	input character

Definition at line 154 of file reader_diff.c.

References FALSE, and TRUE.

Referenced by getNextToken().

◆ isTokenChar()

static SCIP_Bool isTokenChar ( char c )

static

returns whether the given character is a single token

Parameters

c	input character

Definition at line 175 of file reader_diff.c.

References FALSE, and TRUE.

Referenced by getNextToken().

◆ isValueChar()

static SCIP_Bool isValueChar	(	char	c,
		char	nextc,
		SCIP_Bool	firstchar,
		SCIP_Bool *	hasdot,
		LPEXPTYPE *	exptype
	)

static

returns whether the current character is member of a value string

Parameters

c	input character
nextc	next input character
firstchar	is the given character the first char of the token?
hasdot	pointer to update the dot flag
exptype	pointer to update the exponent type

Definition at line 199 of file reader_diff.c.

References FALSE, LP_EXP_NONE, LP_EXP_SIGNED, LP_EXP_UNSIGNED, NULL, and TRUE.

Referenced by getNextToken().

◆ getNextLine()

static SCIP_Bool getNextLine	(	SCIP *	scip,
		LPINPUT *	lpinput
	)

static

reads the next line from the input file into the line buffer; skips comments; returns whether a line could be read

Parameters

scip	SCIP data structure
lpinput	LP reading data

Definition at line 243 of file reader_diff.c.

References BMSclearMemoryArray, commentchars, FALSE, LP_MAX_LINELEN, NULL, SCIPdebugMsg, SCIPfgets(), SCIPfseek(), SCIPwarningMessage(), and TRUE.

Referenced by getNextToken().

◆ swapPointers()

static void swapPointers	(	char **	pointer1,
		char **	pointer2
	)

static

swaps the addresses of two pointers

Parameters

pointer1	first pointer
pointer2	second pointer

Definition at line 334 of file reader_diff.c.

Referenced by getNextToken(), pushBufferToken(), pushToken(), and swapTokenBuffer().

◆ getNextToken()

static SCIP_Bool getNextToken	(	SCIP *	scip,
		LPINPUT *	lpinput
	)

static

reads the next token from the input file into the token buffer; returns whether a token was read

Parameters

scip	SCIP data structure
lpinput	LP reading data

Definition at line 348 of file reader_diff.c.

References FALSE, getNextLine(), isDelimChar(), isTokenChar(), isValueChar(), LP_END, LP_EXP_NONE, LP_MAX_LINELEN, NULL, SCIP_Bool, SCIPdebugMsg, swapPointers(), and TRUE.

Referenced by isNewSection(), readCoefficients(), and readStart().

◆ pushToken()

static void pushToken ( LPINPUT * lpinput )

static

puts the current token on the token stack, such that it is read at the next call to getNextToken()

Parameters

lpinput LP reading data

Definition at line 454 of file reader_diff.c.

References LP_MAX_PUSHEDTOKENS, NULL, and swapPointers().

Referenced by isNewSection(), and readCoefficients().

◆ pushBufferToken()

static void pushBufferToken ( LPINPUT * lpinput )

static

puts the buffered token on the token stack, such that it is read at the next call to getNextToken()

Parameters

lpinput LP reading data

Definition at line 467 of file reader_diff.c.

References LP_MAX_PUSHEDTOKENS, NULL, and swapPointers().

Referenced by readCoefficients().

◆ swapTokenBuffer()

static void swapTokenBuffer ( LPINPUT * lpinput )

static

swaps the current token with the token buffer

Parameters

lpinput LP reading data

Definition at line 480 of file reader_diff.c.

References NULL, and swapPointers().

Referenced by isNewSection(), and readCoefficients().

◆ isNewSection()

static SCIP_Bool isNewSection	(	SCIP *	scip,
		LPINPUT *	lpinput
	)

static

checks whether the current token is a section identifier, and if yes, switches to the corresponding section

Parameters

scip	SCIP data structure
lpinput	LP reading data

Definition at line 491 of file reader_diff.c.

References FALSE, getNextToken(), LP_END, LP_MAX_LINELEN, LP_OBJECTIVE, NULL, pushToken(), SCIP_Bool, SCIP_OBJSENSE_MAXIMIZE, SCIP_OBJSENSE_MINIMIZE, SCIPdebugMsg, swapTokenBuffer(), and TRUE.

Referenced by readCoefficients(), and readStart().

◆ isSign()

static SCIP_Bool isSign	(	LPINPUT *	lpinput,
		int *	sign
	)

static

returns whether the current token is a sign

Parameters

lpinput	LP reading data
sign	pointer to update the sign

Definition at line 569 of file reader_diff.c.

References FALSE, NULL, and TRUE.

Referenced by readCoefficients().

◆ isValue()

static SCIP_Bool isValue	(	SCIP *	scip,
		LPINPUT *	lpinput,
		SCIP_Real *	value
	)

static

returns whether the current token is a value

Parameters

scip	SCIP data structure
lpinput	LP reading data
value	pointer to store the value (unchanged, if token is no value)

Definition at line 594 of file reader_diff.c.

References FALSE, NULL, SCIPinfinity(), and TRUE.

Referenced by readCoefficients().

◆ isSense()

static SCIP_Bool isSense	(	LPINPUT *	lpinput,
		LPSENSE *	sense
	)

static

returns whether the current token is an equation sense

Parameters

lpinput	LP reading data
sense	pointer to store the equation sense, or NULL

Definition at line 626 of file reader_diff.c.

References FALSE, LP_SENSE_EQ, LP_SENSE_GE, LP_SENSE_LE, NULL, and TRUE.

Referenced by readCoefficients().

◆ getVariable()

static SCIP_RETCODE getVariable	(	SCIP *	scip,
		char *	name,
		SCIP_VAR **	var
	)

static

returns the variable with the given name, or creates a new variable if it does not exist

Parameters

scip	SCIP data structure
name	name of the variable
var	pointer to store the variable

Definition at line 657 of file reader_diff.c.

References NULL, SCIP_OKAY, SCIP_READERROR, and SCIPfindVar().

Referenced by readCoefficients().

◆ readStart()

static SCIP_RETCODE readStart	(	SCIP *	scip,
		LPINPUT *	lpinput
	)

static

reads the header of the file

Parameters

scip	SCIP data structure
lpinput	LP reading data

Definition at line 676 of file reader_diff.c.

References getNextToken(), isNewSection(), NULL, and SCIP_OKAY.

Referenced by readDiffFile().

◆ readCoefficients()

static SCIP_RETCODE readCoefficients	(	SCIP *	scip,
		LPINPUT *	lpinput,
		SCIP_Bool	isobjective,
		char *	name,
		int *	coefssize,
		SCIP_VAR ***	vars,
		SCIP_Real **	coefs,
		int *	ncoefs,
		SCIP_Bool *	newsection
	)

static

reads an objective or constraint with name and coefficients

Parameters

scip	SCIP data structure
lpinput	LP reading data
isobjective	indicates whether we are currently reading the coefficients of the objective
name	pointer to store the name of the line; must be at least of size LP_MAX_LINELEN
coefssize	size of vars and coefs arrays
vars	pointer to store the array with variables (must be freed by caller)
coefs	pointer to store the array with coefficients (must be freed by caller)
ncoefs	pointer to store the number of coefficients
newsection	pointer to store whether a new section was encountered

Definition at line 697 of file reader_diff.c.

References FALSE, getNextToken(), getVariable(), isNewSection(), isSense(), isSign(), isValue(), LP_INIT_COEFSSIZE, LP_MAX_LINELEN, MAX, NULL, pushBufferToken(), pushToken(), SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_READERROR, SCIP_Real, SCIPallocBlockMemoryArray, SCIPdebugMsg, SCIPisZero(), SCIPmemccpy(), SCIPreallocBlockMemoryArray, SCIPvarGetName(), SCIPwarningMessage(), swapTokenBuffer(), syntaxError(), and TRUE.

Referenced by readObjective().

◆ readObjective()

static SCIP_RETCODE readObjective	(	SCIP *	scip,
		LPINPUT *	lpinput
	)

static

reads the objective section

Parameters

scip	SCIP data structure
lpinput	LP reading data

Definition at line 897 of file reader_diff.c.

References LP_MAX_LINELEN, NULL, readCoefficients(), SCIP_Bool, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPchgReoptObjective(), SCIPfreeBlockMemoryArrayNull, and TRUE.

Referenced by readDiffFile().

◆ readDiffFile()

static SCIP_RETCODE readDiffFile	(	SCIP *	scip,
		LPINPUT *	lpinput,
		const char *	filename
	)

static

reads a diff file

Parameters

scip	SCIP data structure
lpinput	LP reading data
filename	name of the input file

Definition at line 926 of file reader_diff.c.

References hasError(), LP_END, LP_OBJECTIVE, LP_START, NULL, readObjective(), readStart(), SCIP_CALL, SCIP_INVALIDDATA, SCIP_NOFILE, SCIP_OKAY, SCIP_STAGE_PROBLEM, SCIPerrorMessage, SCIPfclose(), SCIPfopen(), SCIPfreeReoptSolve(), SCIPfreeTransform(), SCIPgetStage(), SCIPisReoptEnabled(), and SCIPprintSysError().

Referenced by SCIPreadDiff().

◆ SCIP_DECL_READERCOPY()

static SCIP_DECL_READERCOPY ( readerCopyDiff )

static

copy method for reader plugins (called when SCIP copies plugins)

Definition at line 986 of file reader_diff.c.

References NULL, READER_NAME, SCIP_CALL, SCIP_OKAY, SCIPincludeReaderDiff(), and SCIPreaderGetName().

◆ SCIP_DECL_READERFREE()

static SCIP_DECL_READERFREE ( readerFreeDiff )

static

destructor of reader to free user data (called when SCIP is exiting)

Definition at line 1000 of file reader_diff.c.

References SCIP_OKAY.

◆ SCIP_DECL_READERREAD()

static SCIP_DECL_READERREAD ( readerReadDiff )

static

problem reading method of reader

Definition at line 1007 of file reader_diff.c.

References SCIP_CALL, SCIP_OKAY, and SCIPreadDiff().

Variable Documentation

◆ commentchars

const char commentchars[] = "\\"

static

Definition at line 107 of file reader_diff.c.

Referenced by getNextLine().

SCIP

Detailed Description

Macros

Typedefs

Enumerations

Functions

Variables

Macro Definition Documentation

◆ READER_NAME

◆ READER_DESC

◆ READER_EXTENSION

◆ LP_MAX_LINELEN

◆ LP_MAX_PUSHEDTOKENS

◆ LP_INIT_COEFSSIZE

Typedef Documentation

◆ LPSECTION

◆ LPEXPTYPE

◆ LPSENSE

◆ LPINPUT

Enumeration Type Documentation

◆ LpSection

◆ LpExpType

◆ LpSense

Function Documentation

◆ syntaxError()

◆ hasError()

◆ isDelimChar()

◆ isTokenChar()

◆ isValueChar()

◆ getNextLine()

◆ swapPointers()

◆ getNextToken()

◆ pushToken()

◆ pushBufferToken()

◆ swapTokenBuffer()

◆ isNewSection()

◆ isSign()

◆ isValue()

◆ isSense()

◆ getVariable()

◆ readStart()

◆ readCoefficients()

◆ readObjective()

◆ readDiffFile()

◆ SCIP_DECL_READERCOPY()

◆ SCIP_DECL_READERFREE()

◆ SCIP_DECL_READERREAD()

Variable Documentation

◆ commentchars