cuts.c
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22 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
47 /* =========================================== general static functions =========================================== */
80 SCIPquadprecProdQD(coef, coef, (sol == NULL ? SCIPvarGetLPSol(vars[cutinds[i]]) : SCIPgetSolVal(scip, sol, vars[cutinds[i]])));
86 SCIPquadprecProdQD(coef, coef, (islocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]])));
90 SCIPquadprecProdQD(coef, coef, (islocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]])));
114 int*RESTRICT inds, /**< pointer to array with variable problem indices of non-zeros in variable vector */
157 int*RESTRICT inds, /**< pointer to array with variable problem indices of non-zeros in variable vector */
202 int* cutinds, /**< array of the problem indices of variables with a non-zero coefficient in the cut */
225 /** calculates the efficacy norm of the given aggregation row, which depends on the "separating/efficacynorm" parameter */
229 SCIP_Real* vals, /**< array of the non-zero coefficients in the vector; this is a quad precision array! */
230 int* inds, /**< array of the problem indices of variables with a non-zero coefficient in the vector */
287 /** calculates the cuts efficacy for the given solution; the cut coefs are stored densely and in quad precision */
292 SCIP_Real* cutcoefs, /**< array of the non-zero coefficients in the cut; this is a quad precision array! */
294 int* cutinds, /**< array of the problem indices of variables with a non-zero coefficient in the cut */
322 /** safely remove all coefficients below the given value; returns TRUE if the cut became redundant */
330 int* cutinds, /**< array of the problem indices of variables with a non-zero coefficient in the cut */
393 /** safely remove all coefficients below the given value; returns TRUE if the cut became redundant */
401 int* cutinds, /**< array of the problem indices of variables with a non-zero coefficient in the cut */
410 /* loop over non-zeros and remove values below minval; values above QUAD_EPSILON are cancelled with their bound
505 /** change given coefficient to new given value, adjust right hand side using the variables bound;
547 /** change given (quad) coefficient to new given value, adjust right hand side using the variables bound;
590 /** scales the cut and then tightens the coefficients of the given cut based on the maximal activity;
591 * see cons_linear.c consdataTightenCoefs() for details; the cut is given in a semi-sparse quad precision array;
599 int* cutinds, /**< array of the problem indices of variables with a non-zero coefficient in the cut */
623 /* compute the maximum activity and maximum absolute coefficient values for all and for integral variables in the cut */
635 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
654 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
705 (SCIP_Longint)scip->set->sepa_maxcoefratio, scip->set->sepa_maxcoefratio, &intscalar, &success) );
726 if( chgQuadCoeffWithBound(scip, vars[cutinds[i]], QUAD(val), intval, cutislocal, QUAD(cutrhs)) )
766 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
776 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
849 /* no coefficient tightening can be performed since the precondition doesn't hold for any of the variables */
855 /* loop over the integral variables and try to tighten the coefficients; see cons_linear for more details */
873 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
896 SCIPdebugPrintf("tightened coefficient from %g to %g; rhs changed from %g to %g; the bounds are [%g,%g]\n",
920 else if( QUAD_TO_DBL(val) > 0.0 && SCIPisLE(scip, maxact - QUAD_TO_DBL(val), QUAD_TO_DBL(*cutrhs)) )
923 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
946 SCIPdebugPrintf("tightened coefficient from %g to %g; rhs changed from %g to %g; the bounds are [%g,%g]\n",
969 else /* due to sorting we can stop completely if the precondition was not fulfilled for this variable */
978 /** scales the cut and then tightens the coefficients of the given cut based on the maximal activity;
979 * see cons_linear.c consdataTightenCoefs() for details; the cut is given in a semi-sparse array;
987 int* cutinds, /**< array of the problem indices of variables with a non-zero coefficient in the cut */
1021 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
1038 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
1088 SCIP_CALL( SCIPcalcIntegralScalar(intcoeffs, *cutnnz, -SCIPsumepsilon(scip), SCIPepsilon(scip),
1089 (SCIP_Longint)scip->set->sepa_maxcoefratio, scip->set->sepa_maxcoefratio, &intscalar, &success) );
1148 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
1158 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
1219 /* no coefficient tightening can be performed since the precondition doesn't hold for any of the variables */
1225 /* loop over the integral variables and try to tighten the coefficients; see cons_linear for more details */
1243 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
1265 SCIPdebugPrintf("tightened coefficient from %g to %g; rhs changed from %g to %g; the bounds are [%g,%g]\n",
1291 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
1313 SCIPdebugPrintf("tightened coefficient from %g to %g; rhs changed from %g to %g; the bounds are [%g,%g]\n",
1336 else /* due to sorting we can stop completely if the precondition was not fulfilled for this variable */
1345 /** perform activity based coefficient tightening on the given cut; returns TRUE if the cut was detected
1353 int* cutinds, /**< array of the problem indices of variables with a non-zero coefficient in the cut */
1386 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
1405 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
1433 /* no coefficient tightening can be performed since the precondition doesn't hold for any of the variables */
1440 /* loop over the integral variables and try to tighten the coefficients; see cons_linear for more details */
1454 SCIP_Real lb = cutislocal ? SCIPvarGetLbLocal(vars[cutinds[i]]) : SCIPvarGetLbGlobal(vars[cutinds[i]]);
1467 SCIPdebugPrintf("tightened coefficient from %g to %g; rhs changed from %g to %g; the bounds are [%g,%g]\n",
1495 SCIP_Real ub = cutislocal ? SCIPvarGetUbLocal(vars[cutinds[i]]) : SCIPvarGetUbGlobal(vars[cutinds[i]]);
1508 SCIPdebugPrintf("tightened coefficient from %g to %g; rhs changed from %g to %g; the bounds are [%g,%g]\n",
1533 else /* due to sorting we can stop completely if the precondition was not fulfilled for this variable */
1545 /* =========================================== aggregation row =========================================== */
1630 SCIPmessageFPrintInfo(messagehdlr, file, "%+.15g<%s> ", QUAD_TO_DBL(val), SCIPvarGetName(vars[aggrrow->inds[i]]));
1653 SCIP_CALL( SCIPduplicateBlockMemoryArray(scip, &(*aggrrow)->vals, source->vals, QUAD_ARRAY_SIZE(nvars)) );
1664 SCIP_CALL( SCIPduplicateBlockMemoryArray(scip, &(*aggrrow)->rowsinds, source->rowsinds, source->nrows) );
1665 SCIP_CALL( SCIPduplicateBlockMemoryArray(scip, &(*aggrrow)->slacksign, source->slacksign, source->nrows) );
1666 SCIP_CALL( SCIPduplicateBlockMemoryArray(scip, &(*aggrrow)->rowweights, source->rowweights, source->nrows) );
1711 SCIP_CALL( SCIPreallocBlockMemoryArray(scip, &aggrrow->rowsinds, aggrrow->rowssize, newsize) );
1712 SCIP_CALL( SCIPreallocBlockMemoryArray(scip, &aggrrow->slacksign, aggrrow->rowssize, newsize) );
1713 SCIP_CALL( SCIPreallocBlockMemoryArray(scip, &aggrrow->rowweights, aggrrow->rowssize, newsize) );
1731 /* Automatically decide, whether we want to use the left or the right hand side of the row in the summation.
1759 SCIP_CALL( varVecAddScaledRowCoefsQuad(aggrrow->inds, aggrrow->vals, &aggrrow->nnz, row, weight) );
1764 /** Removes a given variable @p var from position @p pos the aggregation row and updates the right-hand side according
1765 * to sign of the coefficient, i.e., rhs -= coef * bound, where bound = lb if coef >= 0 and bound = ub, otherwise.
1767 * @note: The choice of global or local bounds depend on the validity (global or local) of the aggregation row.
1769 * @note: The list of non-zero indices will be updated by swapping the last non-zero index to @p pos.
1827 /** add the objective function with right-hand side @p rhs and scaled by @p scale to the aggregation row */
1970 /** calculates the efficacy norm of the given aggregation row, which depends on the "separating/efficacynorm" parameter
1972 * @return the efficacy norm of the given aggregation row, which depends on the "separating/efficacynorm" parameter
1982 /** Adds one row to the aggregation row. Differs from SCIPaggrRowAddRow() by providing some additional
1993 int negslack, /**< should negative slack variables allowed to be used? (0: no, 1: only for integral rows, 2: yes) */
2005 if( SCIPisFeasZero(scip, weight) || SCIProwIsModifiable(row) || (SCIProwIsLocal(row) && !allowlocal) )
2024 else if( SCIPisInfinity(scip, SCIProwGetRhs(row)) || (weight < 0.0 && ! SCIPisInfinity(scip, -SCIProwGetLhs(row))) )
2029 else if( (weight < 0.0 && !SCIPisInfinity(scip, -row->lhs)) || SCIPisInfinity(scip, row->rhs) )
2069 SCIP_CALL( SCIPreallocBlockMemoryArray(scip, &aggrrow->rowsinds, aggrrow->rowssize, newsize) );
2070 SCIP_CALL( SCIPreallocBlockMemoryArray(scip, &aggrrow->slacksign, aggrrow->rowssize, newsize) );
2071 SCIP_CALL( SCIPreallocBlockMemoryArray(scip, &aggrrow->rowweights, aggrrow->rowssize, newsize) );
2081 SCIP_CALL( varVecAddScaledRowCoefsQuad(aggrrow->inds, aggrrow->vals, &aggrrow->nnz, row, weight) );
2101 int negslack, /**< should negative slack variables allowed to be used? (0: no, 1: only for integral rows, 2: yes) */
2127 SCIP_CALL( addOneRow(scip, aggrrow, rows[rowinds[k]], weights[rowinds[k]], sidetypebasis, allowlocal, negslack, maxaggrlen, &rowtoolong) );
2137 SCIP_CALL( addOneRow(scip, aggrrow, rows[k], weights[k], sidetypebasis, allowlocal, negslack, maxaggrlen, &rowtoolong) );
2161 SCIP_Bool* success /**< pointer to return whether post-processing was succesful or cut is redundant */
2189 SCIP_CALL( cutTightenCoefs(scip, cutislocal, cutcoefs, QUAD(&rhs), cutinds, nnz, &redundant) );
2208 *success = ! removeZeros(scip, minallowedcoef, cutislocal, cutcoefs, QUAD(&rhs), cutinds, nnz);
2230 SCIP_Bool* success /**< pointer to return whether the cleanup was successful or if it is useless */
2246 if( removeZerosQuad(scip, SCIPfeastol(scip), cutislocal, cutcoefs, QUAD(cutrhs), cutinds, nnz) )
2255 SCIP_CALL( cutTightenCoefsQuad(scip, cutislocal, cutcoefs, QUAD(cutrhs), cutinds, nnz, &redundant) );
2276 *success = ! removeZerosQuad(scip, minallowedcoef, cutislocal, cutcoefs, QUAD(cutrhs), cutinds, nnz);
2291 *valid = ! removeZerosQuad(scip, SCIPsumepsilon(scip), aggrrow->local, aggrrow->vals, QUAD(&aggrrow->rhs), aggrrow->inds, &aggrrow->nnz);
2349 /** gets the array of corresponding variable problem indices for each non-zero in the aggregation row */
2400 * for the given cut; moves filtered cuts to the end of the array and returns number of selected cuts */
2437 /** move the cut with the highest score to the first position in the array; there must be at least one cut */
2483 SCIP_Real efficacyweight, /**< weight of efficacy (shortest cutoff distance) in score calculation */
2517 /* if there is an incumbent and the factor is not 0.0, compute directed cutoff distances for the incumbent */
2527 intsupportweight * SCIProwGetNumIntCols(cuts[i], scip->set) / (SCIP_Real) SCIProwGetNNonz(cuts[i]) :
2530 objparallelism = objparalweight != 0.0 ? objparalweight * SCIProwGetObjParallelism(cuts[i], scip->set, scip->lp) : 0.0;
2568 intsupportweight * SCIProwGetNumIntCols(cuts[i], scip->set) / (SCIP_Real) SCIProwGetNNonz(cuts[i]) :
2571 objparallelism = objparalweight > 0.0 ? objparalweight * SCIProwGetObjParallelism(cuts[i], scip->set, scip->lp) : 0.0;
2610 nnonforcedcuts = filterWithParallelism(cuts[i], nonforcedcuts, nonforcedscores, nnonforcedcuts, goodscore, goodmaxparall, maxparall);
2613 /* if the maximal number of cuts was exceeded after selecting the forced cuts, we can stop here */
2625 /* if the best cut of the remaining cuts is considered bad, we discard it and all remaining cuts */
2635 /* move the pointers to the next position and filter the remaining cuts to enforce the maximum parallelism constraint */
2640 nnonforcedcuts = filterWithParallelism(selectedcut, nonforcedcuts, nonforcedscores, nnonforcedcuts, goodscore, goodmaxparall, maxparall);
2650 /* =========================================== c-MIR =========================================== */
2661 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
2695 /* we have to avoid cyclic variable bound usage, so we enforce to use only variable bounds variables of smaller index */
2696 /**@todo this check is not needed for continuous variables; but allowing all but binary variables
2719 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
2753 /* we have to avoid cyclic variable bound usage, so we enforce to use only variable bounds variables of smaller index */
2754 /**@todo this check is not needed for continuous variables; but allowing all but binary variables
2770 /** determine the best bounds with respect to the given solution for complementing the given variable */
2776 SCIP_Real boundswitch, /**< fraction of domain up to which lower bound is used in transformation */
2778 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
2779 SCIP_Bool fixintegralrhs, /**< should complementation tried to be adjusted such that rhs gets fractional? */
2781 int* boundsfortrans, /**< bounds that should be used for transformed variables: vlb_idx/vub_idx,
2784 SCIP_BOUNDTYPE* boundtypesfortrans, /**< type of bounds that should be used for transformed variables;
2790 SCIP_BOUNDTYPE* selectedbound, /**< pointer to store whether the lower bound or the upper bound should be preferred */
2801 assert(SCIPvarGetType(var) == SCIP_VARTYPE_CONTINUOUS || ( boundsfortrans[v] == -2 || boundsfortrans[v] == -1 ));
2831 *bestlb = vlbcoefs[k] * (sol == NULL ? SCIPvarGetLPSol(vlbvars[k]) : SCIPgetSolVal(scip, sol, vlbvars[k])) + vlbconsts[k];
2837 /* find closest upper bound in standard upper bound (and variable upper bounds for continuous variables) */
2838 SCIP_CALL( findBestUb(scip, var, sol, usevbds && fixintegralrhs, allowlocal && fixintegralrhs, bestub, bestubtype) );
2869 /* we have to avoid cyclic variable bound usage, so we enforce to use only variable bounds variables of smaller index */
2870 *bestub = vubcoefs[k] * (sol == NULL ? SCIPvarGetLPSol(vubvars[k]) : SCIPgetSolVal(scip, sol, vubvars[k])) + vubconsts[k];
2876 /* find closest lower bound in standard lower bound (and variable lower bounds for continuous variables) */
2877 SCIP_CALL( findBestLb(scip, var, sol, usevbds && fixintegralrhs, allowlocal && fixintegralrhs, bestlb, bestlbtype) );
2886 /* find closest lower bound in standard lower bound (and variable lower bounds for continuous variables) */
2889 /* find closest upper bound in standard upper bound (and variable upper bounds for continuous variables) */
2965 * x^\prime_j := x_j - lb_j,& x_j = x^\prime_j + lb_j,& a^\prime_j = a_j,& \mbox{if lb is used in transformation}\\
2966 * x^\prime_j := ub_j - x_j,& x_j = ub_j - x^\prime_j,& a^\prime_j = -a_j,& \mbox{if ub is used in transformation}
2974 * x^\prime_j := x_j - (bl_j\, zl_j + dl_j),& x_j = x^\prime_j + (bl_j\, zl_j + dl_j),& a^\prime_j = a_j,& \mbox{if vlb is used in transf.} \\
2975 * x^\prime_j := (bu_j\, zu_j + du_j) - x_j,& x_j = (bu_j\, zu_j + du_j) - x^\prime_j,& a^\prime_j = -a_j,& \mbox{if vub is used in transf.}
2978 * move the constant terms \f$ a_j\, dl_j \f$ or \f$ a_j\, du_j \f$ to the rhs, and update the coefficient of the VLB variable:
2990 SCIP_Real boundswitch, /**< fraction of domain up to which lower bound is used in transformation */
2992 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
2993 SCIP_Bool fixintegralrhs, /**< should complementation tried to be adjusted such that rhs gets fractional? */
2995 int* boundsfortrans, /**< bounds that should be used for transformed variables: vlb_idx/vub_idx,
2998 SCIP_BOUNDTYPE* boundtypesfortrans, /**< type of bounds that should be used for transformed variables;
3009 SCIP_Bool* freevariable, /**< stores whether a free variable was found in MIR row -> invalid summation */
3010 SCIP_Bool* localbdsused /**< pointer to store whether local bounds were used in transformation */
3040 /* start with continuous variables, because using variable bounds can affect the untransformed integral
3041 * variables, and these changes have to be incorporated in the transformation of the integral variables
3053 SCIP_CALL( determineBestBounds(scip, vars[cutinds[i]], sol, boundswitch, usevbds, allowlocal, fixintegralrhs,
3055 bestlbs + i, bestubs + i, bestlbtypes + i, bestubtypes + i, selectedbounds + i, freevariable) );
3175 /* remove integral variables that now have a zero coefficient due to variable bound usage of continuous variables
3197 /* determine the best bounds for the integral variable, usevbd can be set to FALSE here as vbds are only used for continous variables */
3198 SCIP_CALL( determineBestBounds(scip, vars[v], sol, boundswitch, FALSE, allowlocal, fixintegralrhs,
3200 bestlbs + i, bestubs + i, bestlbtypes + i, bestubtypes + i, selectedbounds + i, freevariable) );
3209 /* now perform the bound substitution on the remaining integral variables which only uses standard bounds */
3325 /* prefer larger violations; for equal violations, prefer smaller f0 values since then the possibility that
3357 assert(bestubtypes[besti] < 0); /* cannot switch to a variable bound (would lead to further coef updates) */
3364 assert(bestlbtypes[besti] < 0); /* cannot switch to a variable bound (would lead to further coef updates) */
3385 /** Calculate fractionalities \f$ f_0 := b - down(b), f_j := a^\prime_j - down(a^\prime_j) \f$, and derive MIR cut \f$ \tilde{a} \cdot x' \leq down(b) \f$
3400 * x^\prime_j := x_j - lb_j,& x_j = x^\prime_j + lb_j,& a^\prime_j = a_j,& \hat{a}_j := \tilde{a}_j,& \mbox{if lb was used in transformation} \\
3401 * x^\prime_j := ub_j - x_j,& x_j = ub_j - x^\prime_j,& a^\prime_j = -a_j,& \hat{a}_j := -\tilde{a}_j,& \mbox{if ub was used in transformation}
3416 * x^\prime_j := x_j - (bl_j \cdot zl_j + dl_j),& x_j = x^\prime_j + (bl_j\, zl_j + dl_j),& a^\prime_j = a_j,& \hat{a}_j := \tilde{a}_j,& \mbox{(vlb)} \\
3417 * x^\prime_j := (bu_j\, zu_j + du_j) - x_j,& x_j = (bu_j\, zu_j + du_j) - x^\prime_j,& a^\prime_j = -a_j,& \hat{a}_j := -\tilde{a}_j,& \mbox{(vub)}
3430 * \hat{a}_{zl_j} := \hat{a}_{zl_j} - \tilde{a}_j\, bl_j = \hat{a}_{zl_j} - \hat{a}_j\, bl_j,& \mbox{or} \\
3440 int*RESTRICT cutinds, /**< array of variables problem indices for non-zero coefficients in cut */
3443 int*RESTRICT boundtype, /**< stores the bound used for transformed variable (vlb/vub_idx or -1 for lb/ub) */
3465 /* Loop backwards to process integral variables first and be able to delete coefficients of integral variables
3473 /*in debug mode check that all continuous variables of the aggrrow come before the integral variables */
3541 /* move the constant term -a~_j * lb_j == -a^_j * lb_j , or a~_j * ub_j == -a^_j * ub_j to the rhs */
3576 /* now process the continuous variables; postpone deletetion of zeros till all continuous variables have been processed */
3602 SCIPquadprecProdQQ(cutaj, onedivoneminusf0, aj); /* cutaj = varsign[i] * aj * onedivoneminusf0; // a^_j */
3627 /* move the constant term -a~_j * lb_j == -a^_j * lb_j , or a~_j * ub_j == -a^_j * ub_j to the rhs */
3734 * The coefficient of the slack variable s_r is equal to the row's weight times the slack's sign, because the slack
3737 * Depending on the slacks type (integral or continuous), its coefficient in the cut calculates as follows:
3741 * & \hat{a}_r = \tilde{a}_r = down(a^\prime_r) + (f_r - f0)/(1 - f0),& \mbox{if}\qquad f_r > f0 \\
3747 * Substitute \f$ \hat{a}_r \cdot s_r \f$ by adding \f$ \hat{a}_r \f$ times the slack's definition to the cut.
3811 || (slacksign[i] == -1 && SCIPisFeasIntegral(scip, row->lhs - row->constant))) ) /*lint !e613*/
3893 /** calculates an MIR cut out of the weighted sum of LP rows; The weights of modifiable rows are set to 0.0, because
3896 * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
3908 SCIP_Real boundswitch, /**< fraction of domain up to which lower bound is used in transformation */
3910 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
3911 SCIP_Bool fixintegralrhs, /**< should complementation tried to be adjusted such that rhs gets fractional? */
3912 int* boundsfortrans, /**< bounds that should be used for transformed variables: vlb_idx/vub_idx,
3915 SCIP_BOUNDTYPE* boundtypesfortrans, /**< type of bounds that should be used for transformed variables;
3923 int* cutinds, /**< array to store the problem indices of variables with a non-zero coefficient in the cut */
3927 SCIP_Bool* cutislocal, /**< pointer to store whether the generated cut is only valid locally */
3928 SCIP_Bool* success /**< pointer to store whether the returned coefficients are a valid MIR cut */
3990 * x'_j := x_j - (bl_j * zl_j + dl_j), x_j == x'_j + (bl_j * zl_j + dl_j), a'_j == a_j, if vlb is used in transf.
3991 * x'_j := (bu_j * zu_j + du_j) - x_j, x_j == (bu_j * zu_j + du_j) - x'_j, a'_j == -a_j, if vub is used in transf.
3992 * move the constant terms "a_j * dl_j" or "a_j * du_j" to the rhs, and update the coefficient of the VLB variable:
3996 SCIP_CALL( cutsTransformMIR(scip, sol, boundswitch, usevbds, allowlocal, fixintegralrhs, FALSE,
3997 boundsfortrans, boundtypesfortrans, minfrac, maxfrac, tmpcoefs, QUAD(&rhs), cutinds, cutnnz, varsign, boundtype, &freevariable, &localbdsused) );
4016 * x'_j := x_j - lb_j, x_j == x'_j + lb_j, a'_j == a_j, a^_j := a~_j, if lb was used in transformation
4017 * x'_j := ub_j - x_j, x_j == ub_j - x'_j, a'_j == -a_j, a^_j := -a~_j, if ub was used in transformation
4024 * x'_j := x_j - (bl_j * zl_j + dl_j), x_j == x'_j + (bl_j * zl_j + dl_j), a'_j == a_j, a^_j := a~_j, (vlb)
4025 * x'_j := (bu_j * zu_j + du_j) - x_j, x_j == (bu_j * zu_j + du_j) - x'_j, a'_j == -a_j, a^_j := -a~_j, (vub)
4053 SCIP_CALL( cutsRoundMIR(scip, tmpcoefs, QUAD(&rhs), cutinds, cutnnz, varsign, boundtype, QUAD(f0)) );
4059 * The coefficient of the slack variable s_r is equal to the row's weight times the slack's sign, because the slack
4063 * Depending on the slacks type (integral or continuous), its coefficient in the cut calculates as follows:
4077 /* remove all nearly-zero coefficients from MIR row and relax the right hand side correspondingly in order to
4080 SCIP_CALL( postprocessCutQuad(scip, *cutislocal, cutinds, tmpcoefs, cutnnz, QUAD(&rhs), success) );
4084 *success = ! removeZerosQuad(scip, SCIPsumepsilon(scip), *cutislocal, tmpcoefs, QUAD(&rhs), cutnnz, cutinds);
4208 * Given the aggregation, it is transformed to a mixed knapsack set via complementation (using bounds or variable bounds)
4211 * so one would prefer to have integer coefficients for integer variables which are far away from their bounds in the
4214 * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
4226 SCIP_Real boundswitch, /**< fraction of domain up to which lower bound is used in transformation */
4228 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
4230 int* boundsfortrans, /**< bounds that should be used for transformed variables: vlb_idx/vub_idx,
4233 SCIP_BOUNDTYPE* boundtypesfortrans, /**< type of bounds that should be used for transformed variables;
4240 int* cutinds, /**< array to store the problem indices of variables with a non-zero coefficient in the cut */
4242 SCIP_Real* cutefficacy, /**< pointer to store efficacy of best cut; only cuts that are strictly better than the value of
4245 SCIP_Bool* cutislocal, /**< pointer to store whether the generated cut is only valid locally */
4294 /* we only compute bound distance for integer variables; we allocate an array of length aggrrow->nnz to store this, since
4295 * this is the largest number of integer variables. (in contrast to the number of total variables which can be 2 *
4296 * aggrrow->nnz variables: if all are continuous and we use variable bounds to completement, we introduce aggrrow->nnz
4328 * x'_j := x_j - (bl_j * zl_j + dl_j), x_j == x'_j + (bl_j * zl_j + dl_j), a'_j == a_j, if vlb is used in transf.
4329 * x'_j := (bu_j * zu_j + du_j) - x_j, x_j == (bu_j * zu_j + du_j) - x'_j, a'_j == -a_j, if vub is used in transf.
4330 * move the constant terms "a_j * dl_j" or "a_j * du_j" to the rhs, and update the coefficient of the VLB variable:
4335 boundsfortrans, boundtypesfortrans, minfrac, maxfrac, mksetcoefs, QUAD(&mksetrhs), mksetinds, &mksetnnz, varsign, boundtype, &freevariable, &localbdsused) );
4343 SCIPdebug(printCutQuad(scip, sol, mksetcoefs, QUAD(mksetrhs), mksetinds, mksetnnz, FALSE, FALSE));
4381 SCIP_CALL( SCIPcalcIntegralScalar(deltacands, nbounddist, -QUAD_EPSILON, SCIPsumepsilon(scip), (SCIP_Longint)10000, 10000.0, &intscale, &intscalesuccess) );
4457 * x'_j := x_j - lb_j, x_j == x'_j + lb_j, a'_j == a_j, a^_j := a~_j, if lb was used in transformation
4458 * x'_j := ub_j - x_j, x_j == ub_j - x'_j, a'_j == -a_j, a^_j := -a~_j, if ub was used in transformation
4465 * x'_j := x_j - (bl_j * zl_j + dl_j), x_j == x'_j + (bl_j * zl_j + dl_j), a'_j == a_j, a^_j := a~_j, (vlb)
4466 * x'_j := (bu_j * zu_j + du_j) - x_j, x_j == (bu_j * zu_j + du_j) - x'_j, a'_j == -a_j, a^_j := -a~_j, (vub)
4658 efficacy = computeMIREfficacy(scip, tmpcoefs, tmpvalues, QUAD_TO_DBL(mksetrhs), contactivity, contsqrnorm, deltacands[i], ntmpcoefs, minfrac, maxfrac);
4681 efficacy = computeMIREfficacy(scip, tmpcoefs, tmpvalues, QUAD_TO_DBL(mksetrhs), contactivity, contsqrnorm, delta, ntmpcoefs, minfrac, maxfrac);
4691 /* try to improve efficacy by switching complementation of integral variables that are not at their bounds
4707 SCIP_CALL( findBestLb(scip, vars[mksetinds[k]], sol, FALSE, allowlocal, &bestlb, &bestlbtype) );
4712 SCIP_CALL( findBestUb(scip, vars[mksetinds[k]], sol, FALSE, allowlocal, &bestub, &bestubtype) );
4731 tmpvalues[k - intstart] = varsign[k] == +1 ? bestub - SCIPgetSolVal(scip, sol, vars[mksetinds[k]]) : SCIPgetSolVal(scip, sol, vars[mksetinds[k]]) - bestlb;
4734 newefficacy = computeMIREfficacy(scip, tmpcoefs, tmpvalues, QUAD_TO_DBL(newrhs), contactivity, contsqrnorm, bestdelta, ntmpcoefs, minfrac, maxfrac);
4746 assert(bestubtype < 0); /* cannot switch to a variable bound (would lead to further coef updates) */
4753 assert(bestlbtype < 0); /* cannot switch to a variable bound (would lead to further coef updates) */
4793 SCIPdebug(printCutQuad(scip, sol, mksetcoefs, QUAD(mksetrhs), mksetinds, mksetnnz, FALSE, FALSE));
4797 SCIP_CALL( cutsRoundMIR(scip, mksetcoefs, QUAD(&mksetrhs), mksetinds, &mksetnnz, varsign, boundtype, QUAD(f0)) );
4800 SCIPdebug(printCutQuad(scip, sol, mksetcoefs, QUAD(mksetrhs), mksetinds, mksetnnz, FALSE, FALSE));
4804 * The coefficient of the slack variable s_r is equal to the row's weight times the slack's sign, because the slack
4808 * Depending on the slacks type (integral or continuous), its coefficient in the cut calculates as follows:
4820 SCIPdebug(printCutQuad(scip, sol, mksetcoefs, QUAD(mksetrhs), mksetinds, mksetnnz, FALSE, FALSE));
4834 SCIPdebugMessage("efficacy of cmir cut is different than expected efficacy: %f != %f\n", efficacy, bestefficacy);
4841 /* remove all nearly-zero coefficients from MIR row and relax the right hand side correspondingly in order to
4846 SCIP_CALL( postprocessCutQuad(scip, *cutislocal, mksetinds, mksetcoefs, &mksetnnz, QUAD(&mksetrhs), success) );
4850 *success = ! removeZerosQuad(scip, SCIPsumepsilon(scip), *cutislocal, mksetcoefs, QUAD(&mksetrhs), mksetinds, &mksetnnz);
4854 SCIPdebug(printCutQuad(scip, sol, mksetcoefs, QUAD(mksetrhs), mksetinds, mksetnnz, FALSE, FALSE));
4858 mirefficacy = calcEfficacyDenseStorageQuad(scip, sol, mksetcoefs, QUAD_TO_DBL(mksetrhs), mksetinds, mksetnnz);
4915 /* =========================================== flow cover =========================================== */
4927 #define MAXABSVBCOEF 1e+5 /**< maximal absolute coefficient in variable bounds used for snf relaxation */
4944 SCIP_Real d1; /**< right hand side of single-node-flow set plus the sum of all \f$ u_j \f$ for \f$ j \in C^- \f$ */
4945 SCIP_Real d2; /**< right hand side of single-node-flow set plus the sum of all \f$ u_j \f$ for \f$ j \in N^- \f$ */
4947 SCIP_Real mp; /**< smallest variable bound coefficient of variable in \f$ C^{++} (min_{j \in C++} u_j) \f$ */
4951 /** structure that contains all the data that defines the single-node-flow relaxation of an aggregation row */
4963 SCIP_Real* aggrcoefsbin; /**< aggregation coefficient of the original binary var used to define the
4965 SCIP_Real* aggrcoefscont; /**< aggregation coefficient of the original continous var used to define the
4967 SCIP_Real* aggrconstants; /**< aggregation constant used to define the continuous variable in the relaxed set */
4970 /** get solution value and index of variable lower bound (with binary variable) which is closest to the current LP
4971 * solution value of a given variable; candidates have to meet certain criteria in order to ensure the nonnegativity
4972 * of the variable upper bound imposed on the real variable in the 0-1 single node flow relaxation associated with the
4986 SCIP_Real* closestvlb, /**< pointer to store the LP sol value of the closest variable lower bound */
4987 int* closestvlbidx /**< pointer to store the index of the closest vlb; -1 if no vlb was found */
4995 assert(bestsub == SCIPvarGetUbGlobal(var) || bestsub == SCIPvarGetUbLocal(var)); /*lint !e777*/
5040 /* if the variable is not active the problem index is -1, so we cast to unsigned int before the comparison which
5048 /* check if current variable lower bound l~_i * x_i + d_i imposed on y_j meets the following criteria:
5052 * 0. no other non-binary variable y_k has used a variable bound with x_i to get transformed variable y'_k yet
5100 /** get LP solution value and index of variable upper bound (with binary variable) which is closest to the current LP
5101 * solution value of a given variable; candidates have to meet certain criteria in order to ensure the nonnegativity
5102 * of the variable upper bound imposed on the real variable in the 0-1 single node flow relaxation associated with the
5116 SCIP_Real* closestvub, /**< pointer to store the LP sol value of the closest variable upper bound */
5117 int* closestvubidx /**< pointer to store the index of the closest vub; -1 if no vub was found */
5125 assert(bestslb == SCIPvarGetLbGlobal(var) || bestslb == SCIPvarGetLbLocal(var)); /*lint !e777*/
5170 /* if the variable is not active the problem index is -1, so we cast to unsigned int before the comparison which
5182 * 0. no other non-binary variable y_k has used a variable bound with x_i to get transformed variable y'_k
5230 /** determines the bounds to use for constructing the single-node-flow relaxation of a variable in
5240 int varposinrow, /**< position of variable in the rowinds array for which the bounds should be determined */
5244 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
5245 SCIP_Real boundswitch, /**< fraction of domain up to which lower bound is used in transformation */
5254 SCIP_BOUNDTYPE* selectedbounds, /**< pointer to store the preferred bound for the transformation */
5281 SCIP_CALL( findBestLb(scip, var, sol, FALSE, allowlocal, &bestslb[varposinrow], &bestslbtype[varposinrow]) );
5282 SCIP_CALL( findBestUb(scip, var, sol, FALSE, allowlocal, &bestsub[varposinrow], &bestsubtype[varposinrow]) );
5293 SCIPdebugMsg(scip, " %d: %g <%s, idx=%d, lp=%g, [%g(%d),%g(%d)]>:\n", varposinrow, rowcoef, SCIPvarGetName(var), probidx,
5294 solval, bestslb[varposinrow], bestslbtype[varposinrow], bestsub[varposinrow], bestsubtype[varposinrow]);
5296 /* mixed integer set cannot be relaxed to 0-1 single node flow set because both simple bounds are -infinity
5299 if( SCIPisInfinity(scip, -bestslb[varposinrow]) && SCIPisInfinity(scip, bestsub[varposinrow]) )
5305 /* get closest lower bound that can be used to define the real variable y'_j in the 0-1 single node flow
5318 SCIP_CALL( getClosestVlb(scip, var, sol, rowcoefs, binvarused, bestsub[varposinrow], rowcoef, &bestvlb, &bestvlbidx) );
5327 /* get closest upper bound that can be used to define the real variable y'_j in the 0-1 single node flow
5340 SCIP_CALL( getClosestVub(scip, var, sol, rowcoefs, binvarused, bestslb[varposinrow], rowcoef, &bestvub, &bestvubidx) );
5348 SCIPdebugMsg(scip, " bestlb=%g(%d), bestub=%g(%d)\n", bestlb[varposinrow], bestlbtype[varposinrow], bestub[varposinrow], bestubtype[varposinrow]);
5350 /* mixed integer set cannot be relaxed to 0-1 single node flow set because there are no suitable bounds
5361 /* select best upper bound if it is closer to the LP value of y_j and best lower bound otherwise and use this bound
5362 * to define the real variable y'_j with 0 <= y'_j <= u'_j x_j in the 0-1 single node flow relaxation;
5365 if( SCIPisEQ(scip, solval, (1.0 - boundswitch) * bestlb[varposinrow] + boundswitch * bestub[varposinrow]) && bestlbtype[varposinrow] >= 0 )
5369 else if( SCIPisEQ(scip, solval, (1.0 - boundswitch) * bestlb[varposinrow] + boundswitch * bestub[varposinrow])
5374 else if( SCIPisLE(scip, solval, (1.0 - boundswitch) * bestlb[varposinrow] + boundswitch * bestub[varposinrow]) )
5380 assert(SCIPisGT(scip, solval, (1.0 - boundswitch) * bestlb[varposinrow] + boundswitch * bestub[varposinrow]));
5395 else if ( selectedbounds[varposinrow] == SCIP_BOUNDTYPE_UPPER && bestubtype[varposinrow] >= 0 )
5410 /** construct a 0-1 single node flow relaxation (with some additional simple constraints) of a mixed integer set
5417 SCIP_Real boundswitch, /**< fraction of domain up to which lower bound is used in transformation */
5418 SCIP_Bool allowlocal, /**< should local information allowed to be used, resulting in a local cut? */
5425 SCIP_Bool* localbdsused /**< pointer to store whether local bounds were used in transformation */
5448 SCIPdebugMsg(scip, "--------------------- construction of SNF relaxation ------------------------------------\n");
5466 /* array to store whether a binary variable is in the row (-1) or has been used (1) due to variable bound usage */
5483 SCIP_CALL( determineBoundForSNF(scip, sol, vars, rowcoefs, rowinds, i, binvarused, allowlocal, boundswitch,
5484 bestlb, bestub, bestslb, bestsub, bestlbtype, bestubtype, bestslbtype, bestsubtype, selectedbounds, &freevariable) );
5542 /* store for y_j that bestlb is the bound used to define y'_j and that y'_j is the associated real variable
5572 /* store aggregation information for y'_j for transforming cuts for the SNF relaxation back to the problem variables later */
5601 SCIPdebugMsg(scip, " --> bestlb used for trans: ... %s y'_%d + ..., y'_%d <= %g x_%d (=1), rhs=%g-(%g*%g)=%g\n",
5602 snf->transvarcoefs[snf->ntransvars] == 1 ? "+" : "-", snf->ntransvars, snf->ntransvars, snf->transvarvubcoefs[snf->ntransvars],
5603 snf->ntransvars, QUAD_TO_DBL(transrhs) + QUAD_TO_DBL(rowcoeftimesbestsub), QUAD_TO_DBL(rowcoef), bestsub, QUAD_TO_DBL(transrhs));
5619 * y'_j = - ( a_j ( y_j - d_j ) + c_j x_j ) with 0 <= y'_j <= - ( a_j l~_j + c_j ) x_j if a_j > 0
5651 /* store aggregation information for y'_j for transforming cuts for the SNF relaxation back to the problem variables later */
5681 SCIPdebugMsg(scip, " --> bestlb used for trans: ... %s y'_%d + ..., y'_%d <= %g x_%d (=%s), rhs=%g-(%g*%g)=%g\n",
5682 snf->transvarcoefs[snf->ntransvars] == 1 ? "+" : "-", snf->ntransvars, snf->ntransvars, snf->transvarvubcoefs[snf->ntransvars],
5683 snf->ntransvars, SCIPvarGetName(vlbvars[bestlbtype[i]]), QUAD_TO_DBL(transrhs) + QUAD_TO_DBL(rowcoeftimesvlbconst), QUAD_TO_DBL(rowcoef),
5726 /* store aggregation information for y'_j for transforming cuts for the SNF relaxation back to the problem variables later */
5755 SCIPdebugMsg(scip, " --> bestub used for trans: ... %s y'_%d + ..., Y'_%d <= %g x_%d (=1), rhs=%g-(%g*%g)=%g\n",
5756 snf->transvarcoefs[snf->ntransvars] == 1 ? "+" : "-", snf->ntransvars, snf->ntransvars, snf->transvarvubcoefs[snf->ntransvars],
5757 snf->ntransvars, QUAD_TO_DBL(transrhs) + QUAD_TO_DBL(rowcoeftimesbestslb), QUAD_TO_DBL(rowcoef), bestslb[i], QUAD_TO_DBL(transrhs));
5774 * y'_j = - ( a_j ( y_j - d_j ) + c_j x_j ) with 0 <= y'_j <= - ( a_j u~_j + c_j ) x_j if a_j < 0,
5803 /* store aggregation information for y'_j for transforming cuts for the SNF relaxation back to the problem variables later */