/** reads an objective or constraint with name and coefficients */
static
SCIP_RETCODE readCoefficients(
SCIP* scip, /**< SCIP data structure */
LPINPUT* lpinput, /**< LP reading data */
SCIP_Bool isobjective, /**< indicates whether we are currently reading the coefficients of the objective */
char* name, /**< pointer to store the name of the line; must be at least of size
* LP_MAX_LINELEN */
SCIP_VAR*** vars, /**< pointer to store the array with variables (must be freed by caller) */
SCIP_Real** coefs, /**< pointer to store the array with coefficients (must be freed by caller) */
int* ncoefs, /**< pointer to store the number of coefficients */
SCIP_Bool* newsection /**< pointer to store whether a new section was encountered */
)
{
SCIP_Bool havesign;
SCIP_Bool havevalue;
SCIP_Real coef;
int coefsign;
int coefssize;
assert(lpinput != NULL);
assert(name != NULL);
assert(vars != NULL);
assert(coefs != NULL);
assert(ncoefs != NULL);
assert(newsection != NULL);
*vars = NULL;
*coefs = NULL;
*name = '\0';
*ncoefs = 0;
*newsection = FALSE;
/* read the first token, which may be the name of the line */
if( getNextToken(scip, lpinput) )
{
/* check if we reached a new section */
if( isNewSection(scip, lpinput) )
{
*newsection = TRUE;
return SCIP_OKAY;
}
/* remember the token in the token buffer */
swapTokenBuffer(lpinput);
/* get the next token and check, whether it is a colon */
if( getNextToken(scip, lpinput) )
{
if( strcmp(lpinput->token, ":") == 0 )
{
/* the second token was a colon: the first token is the line name */
(void)SCIPmemccpy(name, lpinput->tokenbuf, '\0', LP_MAX_LINELEN);
name[LP_MAX_LINELEN - 1] = '\0';
SCIPdebugMessage("(line %d) read constraint name: '%s'\n", lpinput->linenumber, name);
}
else
{
/* the second token was no colon: push the tokens back onto the token stack and parse them as coefficients */
pushToken(lpinput);
pushBufferToken(lpinput);
}
}
else
{
/* there was only one token left: push it back onto the token stack and parse it as coefficient */
pushBufferToken(lpinput);
}
}
/* initialize buffers for storing the coefficients */
coefssize = LP_INIT_COEFSSIZE;
SCIP_CALL( SCIPallocMemoryArray(scip, vars, coefssize) );
SCIP_CALL( SCIPallocMemoryArray(scip, coefs, coefssize) );
/* read the coefficients */
coefsign = +1;
coef = 1.0;
havesign = FALSE;
havevalue = FALSE;
*ncoefs = 0;
while( getNextToken(scip, lpinput) )
{
SCIP_VAR* var;
/* check if we read a sign */
if( isSign(lpinput, &coefsign) )
{
SCIPdebugMessage("(line %d) read coefficient sign: %+d\n", lpinput->linenumber, coefsign);
havesign = TRUE;
continue;
}
/* check if we read a value */
if( isValue(scip, lpinput, &coef) )
{
SCIPdebugMessage("(line %d) read coefficient value: %g with sign %+d\n", lpinput->linenumber, coef, coefsign);
if( havevalue )
{
syntaxError(scip, lpinput, "two consecutive values.");
return SCIP_OKAY;
}
havevalue = TRUE;
continue;
}
/* check if we reached an equation sense */
if( isSense(lpinput, NULL) )
{
if( isobjective )
{
syntaxError(scip, lpinput, "no sense allowed in objective");
return SCIP_OKAY;
}
/* put the sense back onto the token stack */
pushToken(lpinput);
break;
}
/* check if we reached a new section, that will be only allowed when having no current sign and value and if we
* are not in the quadratic part
*/
if( (isobjective || (!havevalue && !havesign)) && isNewSection(scip, lpinput) )
{
if( havesign && !havevalue )
{
SCIPwarningMessage(scip, "skipped single sign %c without value or variable in objective\n", coefsign == 1 ? '+' : '-');
}
else if( isobjective && havevalue && !SCIPisZero(scip, coef) )
{
SCIPwarningMessage(scip, "constant term %+g in objective is skipped\n", coef * coefsign);
}
*newsection = TRUE;
return SCIP_OKAY;
}
/* check if we start a quadratic part */
if( *lpinput->token == '[' )
{
syntaxError(scip, lpinput, "diff reader does not support quadratic objective function.");
return SCIP_READERROR;
}
/* all but the first coefficient need a sign */
if( *ncoefs > 0 && !havesign )
{
syntaxError(scip, lpinput, "expected sign ('+' or '-') or sense ('<' or '>').");
return SCIP_OKAY;
}
/* check if the last variable should be squared */
if( *lpinput->token == '^' )
{
syntaxError(scip, lpinput, "diff reader does not support quadratic objective function.");
return SCIP_READERROR;
}
else
{
/* the token is a variable name: get the corresponding variable */
SCIP_CALL( getVariable(scip, lpinput->token, &var) );
}
/* insert the linear coefficient */
SCIPdebugMessage("(line %d) read linear coefficient: %+g<%s>\n", lpinput->linenumber, coefsign * coef, SCIPvarGetName(var));
if( !SCIPisZero(scip, coef) )
{
/* resize the vars and coefs array if needed */
if( *ncoefs >= coefssize )
{
coefssize *= 2;
coefssize = MAX(coefssize, (*ncoefs)+1);
SCIP_CALL( SCIPreallocMemoryArray(scip, vars, coefssize) );
SCIP_CALL( SCIPreallocMemoryArray(scip, coefs, coefssize) );
}
assert(*ncoefs < coefssize);
/* add coefficient */
(*vars)[*ncoefs] = var;
(*coefs)[*ncoefs] = coefsign * coef;
(*ncoefs)++;
}
/* reset the flags and coefficient value for the next coefficient */
coefsign = +1;
coef = 1.0;
havesign = FALSE;
havevalue = FALSE;
}
return SCIP_OKAY;
}
/** checks whether the current token is a section identifier, and if yes, switches to the corresponding section */
static
SCIP_Bool isNewSection(
SCIP* scip, /**< SCIP data structure */
BLKINPUT* blkinput /**< BLK reading data */
)
{
SCIP_Bool iscolon;
assert(blkinput != NULL);
/* remember first token by swapping the token buffer */
swapTokenBuffer(blkinput);
/* look at next token: if this is a ':', the first token is a name and no section keyword */
iscolon = FALSE;
if( getNextToken(blkinput) )
{
iscolon = (strcmp(blkinput->token, ":") == 0);
pushToken(blkinput);
}
/* reinstall the previous token by swapping back the token buffer */
swapTokenBuffer(blkinput);
/* check for ':' */
if( iscolon )
return FALSE;
if( strcasecmp(blkinput->token, "PRESOLVED") == 0 )
{
SCIPdebugMessage("(line %d) new section: PRESOLVED\n", blkinput->linenumber);
blkinput->section = BLK_PRESOLVED;
return TRUE;
}
if( strcasecmp(blkinput->token, "NBLOCKS") == 0 )
{
SCIPdebugMessage("(line %d) new section: NBLOCKS\n", blkinput->linenumber);
blkinput->section = BLK_NBLOCKS;
return TRUE;
}
if( strcasecmp(blkinput->token, "BLOCK") == 0 )
{
int blocknr;
blkinput->section = BLK_BLOCK;
if( getNextToken(blkinput) )
{
/* read block number */
if( isInt(scip, blkinput, &blocknr) )
{
assert(blocknr >= 0);
assert(blocknr <= blkinput->nblocks);
blkinput->blocknr = blocknr-1;
}
else
syntaxError(scip, blkinput, "no block number after block keyword!\n");
}
else
syntaxError(scip, blkinput, "no block number after block keyword!\n");
SCIPdebugMessage("new section: BLOCK %d\n", blkinput->blocknr);
return TRUE;
}
if( strcasecmp(blkinput->token, "MASTERCONSS") == 0 )
{
blkinput->section = BLK_MASTERCONSS;
SCIPdebugMessage("new section: MASTERCONSS\n");
return TRUE;
}
if( strcasecmp(blkinput->token, "END") == 0 )
{
SCIPdebugMessage("(line %d) new section: END\n", blkinput->linenumber);
blkinput->section = BLK_END;
return TRUE;
}
return FALSE;
}
/** checks whether the current token is a section identifier, and if yes, switches to the corresponding section */
static
SCIP_Bool isNewSection(
SCIP* scip, /**< SCIP data structure */
LPINPUT* lpinput /**< LP reading data */
)
{
SCIP_Bool iscolon;
size_t len;
assert(lpinput != NULL);
/* remember first token by swapping the token buffer */
swapTokenBuffer(lpinput);
/* look at next token: if this is a ':', the first token is a name and no section keyword */
iscolon = FALSE;
if( getNextToken(scip, lpinput) )
{
iscolon = (*lpinput->token == ':');
pushToken(lpinput);
}
/* reinstall the previous token by swapping back the token buffer */
swapTokenBuffer(lpinput);
/* check for ':' */
if( iscolon )
return FALSE;
len = strlen(lpinput->token);
assert(len < LP_MAX_LINELEN);
/* the section keywords are at least 2 characters up to 8 or exactly 15 characters long */
if( len > 1 && (len < 9 || len == 15) )
{
char token[16];
int c = 0;
while( lpinput->token[c] != '\0' )
{
token[c] = toupper(lpinput->token[c]); /*lint !e734*/
++c;
assert(c < 16);
}
token[c] = '\0';
if( (len == 3 && strcmp(token, "MIN") == 0)
|| (len == 7 && strcmp(token, "MINIMUM") == 0)
|| (len == 8 && strcmp(token, "MINIMIZE") == 0) )
{
SCIPdebugMessage("(line %d) new section: OBJECTIVE\n", lpinput->linenumber);
lpinput->section = LP_OBJECTIVE;
lpinput->objsense = SCIP_OBJSENSE_MINIMIZE;
return TRUE;
}
if( (len == 3 && strcmp(token, "MAX") == 0)
|| (len == 7 && strcmp(token, "MAXIMUM") == 0)
|| (len == 8 && strcmp(token, "MAXIMIZE") == 0) )
{
SCIPdebugMessage("(line %d) new section: OBJECTIVE\n", lpinput->linenumber);
lpinput->section = LP_OBJECTIVE;
lpinput->objsense = SCIP_OBJSENSE_MAXIMIZE;
return TRUE;
}
if( len == 3 && strcmp(token, "END") == 0 )
{
SCIPdebugMessage("(line %d) new section: END\n", lpinput->linenumber);
lpinput->section = LP_END;
return TRUE;
}
}
return FALSE;
}
