CP-SAT Options#
ampl: option solver cpsat; # change the solver
ampl: option cpsat_options 'option1=value1 option2=value2'; # specify options
ampl: solve; # solve the problem
Solver options obtained with $ cpsat -=.
CP-SAT Optimizer Options for AMPL
--------------------------------------------
To set these options, assign a string specifying their values to the AMPL
option "cpsat_options". For example:
ampl: option cpsat_options 'timelim=60 threads=4';
CP-SAT works with integer variables and integer coefficients only. Alldiff,
count, numberof, if-then-else, min, max, abs, and/or/indicator constraints are
passed natively.
'' Options:
acc:_all
Solver acceptance level for all constraints and expressions. Value
meaning: as described in the specific acc:... options.
Can be useful to disable all reformulations (acc:_all=2), or force
linearization (acc:_all=0.)
acc:abs
Solver acceptance level for 'AbsConstraint' as flat constraint, default
2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:alldiff
Solver acceptance level for 'AllDiffConstraint' as flat constraint,
default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:and (acc:forall)
Solver acceptance level for 'AndConstraint' as flat constraint, default
2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:count
Solver acceptance level for 'CountConstraint' as flat constraint,
default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:ifthen
Solver acceptance level for 'IfThenConstraint' as flat constraint,
default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:impl
Solver acceptance level for 'ImplicationConstraint' as flat constraint,
default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:indeq (acc:indlineq)
Solver acceptance level for 'IndicatorConstraintLinEQ' as flat
constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:indge (acc:indlinge)
Solver acceptance level for 'IndicatorConstraintLinGE' as flat
constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:indle (acc:indlinle)
Solver acceptance level for 'IndicatorConstraintLinLE' as flat
constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:intdiv
Solver acceptance level for 'IntDivConstraint' as flat constraint,
default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:lineq
Solver acceptance level for 'LinConEQ' as flat constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:linge
Solver acceptance level for 'LinConGE' as flat constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:linle
Solver acceptance level for 'LinConLE' as flat constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:linrange (acc:linrng)
Solver acceptance level for 'LinConRange' as flat constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:max
Solver acceptance level for 'MaxConstraint' as flat constraint, default
2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:min
Solver acceptance level for 'MinConstraint' as flat constraint, default
2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:mod
Solver acceptance level for 'ModConstraint' as flat constraint, default
2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:mul
Solver acceptance level for 'MulConstraint' as flat constraint, default
2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:numberofconst
Solver acceptance level for 'NumberofConstConstraint' as flat
constraint, default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:numberofvar
Solver acceptance level for 'NumberofVarConstraint' as flat constraint,
default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:or (acc:exists)
Solver acceptance level for 'OrConstraint' as flat constraint, default
2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
acc:powc (acc:powconstexp)
Solver acceptance level for 'PowConstExpConstraint' as flat constraint,
default 2:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted but automatic redefinition will be used where possible
2 - Accepted natively and preferred
alg:linearization (linearization_level)
Level of linearization of the CP model (default 1):
0 - No linearization
1 - Linearize some constraints (default)
2 - Full linearization
alg:relax (relax)
0*/1: Whether to relax integrality of variables.
alg:start (warmstart)
Whether to use incoming primal (and dual, for LP) variable values in a
warmstart:
0 - No
1 - Yes (for LP: if there is no incoming alg:basis)
2 - Yes (for LP: omitting the incoming alg:basis, if any)
3 - Yes (for LP: together with the incoming alg:basis, if any;
default).
cvt:bigM (cvt:bigm, cvt:mip:bigM, cvt:mip:bigm)
Default value of big-M for linearization of logical constraints. Not
used by default. Use with care (prefer tight bounds). Should be smaller
than (1.0 / [integrality tolerance])
cvt:compl (cvt:complementarity)
Complementarity conversion method (if not accepted natively, see
acc:compl and acc:nlcompl). Default 0:
0 - Disjunction: a<=0 || b<=0, a>=0, b>=0
1 - Product: a*b=cvt:compl:tol
2 - Fischer-Burmeister function: sqrt(a^2+b^2+2*cvt:compl:tol)=a+b
3 - min(a,b)=0
cvt:compl:tol (cvt:compl:eps, compl:eps)
Tolerance parameter for the product and Fischer-Burmeister encodings of
complementarity, see cvt:compl. Default 1e-9.
cvt:dvelim (dvelim)
Eliminate AMPL defined variables by substitution into linear, quadratic,
and polynomial expressions:
0 - Do not eliminate, always instantiate the variables.
1 - Eliminate only those used once.
2 - (Default). Always substitute where possible, even if the variable
needs to be instantiated for use in other places. Can introduce
redundancy but proves efficient in many cases.
See also cvt:pre:unnest, as well as AMPL options linelim and substout.
cvt:expcones (expcones)
0*/1: Recognize exponential cones.
cvt:expr:nlassign (expr:nlassign)
Above which reference count, an algebraic formula node should be
assigned to a variable (see acc: options). 0 means all nodes assigned.
Default 1.
cvt:expr:nlreif (expr:nlreif, expr:nlreify)
Above which reference count, a logical formula node should be assigned
(reified) to a variable (see acc: options). 0 means all nodes reified.
Default 1.
cvt:mip:eps (cvt:cmp:eps, cmp:eps)
Tolerance for strict comparison of continuous variables for MIP. Applies
to <, >, and != operators. Also applies to negation of conditional
comparisons: b==1 <==> x<=5 means that with b==0, x>=5+eps. Normally
should be larger or equal to the solver's feasibility tolerance.
Default: 1e-4.
cvt:mip:intprodbits (intprodbits)
Products x*y of variables, when not accepted natively, with an integer
factor of finite bounds (and the other factor bounded): exact MIP
reformulation by binary expansion of the integer factor with the smaller
range if it needs at most this many binary variables. Default 30.
Otherwise, and with 0, such products are approximated as
((x+y)^2-x^2-y^2)/2 with piecewise-linear squares, as for continuous
factors. Products with a binary factor are always exact.
cvt:multoutcard (multoutcard)
Up to which (estimated) QP matrix cardinality should a product of 2
linear expressions be multiplied out. Default 1.
Low value can speed up model input, but prone to numerical issues.
cvt:names (names, modelnames)
Whether to read or generate variable / constraint / objective names:
0 - No names
1 - (Default) Only provide names if at least one of .col / .row name
files was written by AMPL (AMPL: `option [<solver>_]auxfiles rc;`)
2 - Read names from AMPL, but create generic names if not provided
3 - Create generic names.
cvt:nlobj (passnlobj)
0*/1: Pass nonlinear objective terms to the solver. When 0, if the
solver accepts nonlinear constraints, such a constraint will be created
with those, otherwise linearly approximated. With cvt:quadobj=0, ensures
the objective is linear.
cvt:pl:domain (pl:domain, pldomain)
Max absolute value of the argument of a piecewise-linear expression
converted to SOS2 (and further to MIP if SOS2 is not accepted natively).
In the MIP reformulation, the solver's feasibility tolerance is
amplified by up to this value. Not used by default: then an unbounded
argument is an error in the MIP reformulation, and native SOS2 gets
exact rays for unbounded sides. Use with care (prefer tight bounds).
cvt:plapprox:domain (plapprox:domain, plapproxdomain)
For piecewise-linear approximated functions, both arguments and result
are bounded to +-[pladomain]. Default 1e6.
cvt:plapprox:reltol (plapprox:reltol, plapproxreltol)
Relative tolerance for piecewise-linear approximation. Default 0.01.
cvt:pow2_as_qp (pow2_as_qp, pow2asqp)
0/1*: whenever both quadratics and ^2 are accepted, submit (expr)^2 as
out-multiplied quadratics, if (expr) is linear.
See also cvt:multoutcard, cvt:quadobj, cvt:quadcon.
cvt:pre:all
0/1*: Set to 0 to disable most presolve in the flat converter.
cvt:pre:auxint (auxint)
0/1*: Submit as integer the auxiliary result variables whose integrality
is implied by their defining constraint (if-then-else, min, max, abs,
count, numberof, integer linear and quadratic functions of integer
arguments). 0: submit them as continuous (MP keeps the integrality for
its reformulations). Variables required to have their type by a
submitted constraint, e.g., indicator binaries, are not affected.
cvt:pre:boundlogarg (boundlogarg)
0*/1: Bound logarithm arguments to nonnegative.
cvt:pre:boundsbest (boundsbest, bestbounds)
0*/1/2/3/4: Submit best-known variable bounds to the solver (can inhibit
its presolve):
0 - no, hard bounds only
1 - all variables
2 - all but the result variables of smooth nonlinear expressions (exp,
log, pow, trigonometric functions, divisions, products), which keep
their hard bounds
3 - only those variables
4 - all variables if the submitted model has no nonlinear or quadratic
constraints or objectives, none otherwise (for solvers whose nonlinear
relaxations are solved by a barrier method; MP2NL sets it for such
subsolvers).
Note: when a variable can be fixed, the stronger bounds are always
submitted.
cvt:pre:continuous_fixed_vars (continuous_fixed_vars, ctg_fixed)
0/1*: Make fixed variables continuous, to avoid fake MIPs.
cvt:pre:ctx2bndeq (ctx2bndeq)
0/1*: Propagate exact context into conditional (dis)equalities-to-bound,
vs always mixed. Can be affected by cvt:pre:ineq2bndeq. See #267.
cvt:pre:ctx2count (ctx2count)
DEPRECATED. Use ctx2bndeq. NEW DEFAULT.
Propagate exact context into atleast/atmost/exactly, count and numberof
expressions, vs always mixed. Bitwise OR of the following values:
1 - atleast/atmost/exactly, count
2 - numberof with constant reference value
4 - numberof with variable reference value.
Default 7, see #267.
cvt:pre:ctx2ineq (ctx2ineq)
0/1*: Propagate exact context into conditional inequalities, vs always
mixed. See #267.
Finer control provided by cvt:pre:ctx:cond...(le/ge) options.
cvt:pre:ctx:abs (ctx:abs)
Controls propagation of context into abs() expressions, which could
affect reformulations of abs() and its arguments (see the acc: options).
Bitwise OR of the following values:
1 - Propagate positive context exactly (otherwise always mixed)
2 - Propagate negative context exactly (otherwise always mixed)
Default 3. See mp.ampl.com/components.html#mathematical-background.
cvt:pre:ctx:acos (ctx:acos)
Context propagation for 'Acos' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:acosh (ctx:acosh)
Context propagation for 'Acosh' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:alldiff (ctx:alldiff)
Context propagation for 'AllDiff' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:and (ctx:and)
Context propagation for 'And' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:asin (ctx:asin)
Context propagation for 'Asin' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:asinh (ctx:asinh)
Context propagation for 'Asinh' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:atan (ctx:atan)
Context propagation for 'Atan' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:atanh (ctx:atanh)
Context propagation for 'Atanh' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:call (ctx:call)
Context propagation for 'Call' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:ceil (ctx:ceil)
Context propagation for 'Ceil' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condlineq (ctx:condlineq)
Context propagation for 'Conditional< AlgebraicConstraint< LinTerms,
RhsEQ > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condlinge (ctx:condlinge)
Context propagation for 'Conditional< AlgebraicConstraint< LinTerms,
RhsGE > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condlingt (ctx:condlingt)
Context propagation for 'Conditional< AlgebraicConstraint< LinTerms,
RhsGT > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condlinle (ctx:condlinle)
Context propagation for 'Conditional< AlgebraicConstraint< LinTerms,
RhsLE > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condlinlt (ctx:condlinlt)
Context propagation for 'Conditional< AlgebraicConstraint< LinTerms,
RhsLT > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condquadeq (ctx:condquadeq)
Context propagation for 'Conditional< AlgebraicConstraint<
QuadAndLinTerms, RhsEQ > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condquadge (ctx:condquadge)
Context propagation for 'Conditional< AlgebraicConstraint<
QuadAndLinTerms, RhsGE > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condquadgt (ctx:condquadgt)
Context propagation for 'Conditional< AlgebraicConstraint<
QuadAndLinTerms, RhsGT > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condquadle (ctx:condquadle)
Context propagation for 'Conditional< AlgebraicConstraint<
QuadAndLinTerms, RhsLE > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:condquadlt (ctx:condquadlt)
Context propagation for 'Conditional< AlgebraicConstraint<
QuadAndLinTerms, RhsLT > >' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:cos (ctx:cos)
Context propagation for 'Cos' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:cosh (ctx:cosh)
Context propagation for 'Cosh' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:count (ctx:count)
Context propagation for 'Count' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:div (ctx:div)
Context propagation for 'Div' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:equiv (ctx:equiv)
Context propagation for 'Equivalence' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:exp (ctx:exp)
Context propagation for 'Exp' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:expa (ctx:expa)
Context propagation for 'ExpA' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:floor (ctx:floor)
Context propagation for 'Floor' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:ifthen (ctx:ifthen)
Context propagation for 'IfThen' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:impl (ctx:impl)
Context propagation for 'Implication' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:intdiv (ctx:intdiv)
Context propagation for 'IntDiv' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:linfn (ctx:linfn)
Context propagation for 'LinearFunctionalConstraint' expression, see
cvt:pre:ctx:abs.
cvt:pre:ctx:log (ctx:log)
Context propagation for 'Log' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:loga (ctx:loga)
Context propagation for 'LogA' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:logi (ctx:logi)
Context propagation for 'Logistic' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:max (ctx:max)
Context propagation for 'Max' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:min (ctx:min)
Context propagation for 'Min' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:mod (ctx:mod)
Context propagation for 'Mod' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:mul (ctx:mul)
Context propagation for 'Mul' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:not (ctx:not)
Context propagation for 'Not' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:numberofconst (ctx:numberofconst)
Context propagation for 'NumberofConst' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:numberofvar (ctx:numberofvar)
Context propagation for 'NumberofVar' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:or (ctx:or)
Context propagation for 'Or' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:pl (ctx:pl)
Context propagation for 'PL' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:pow (ctx:pow)
Context propagation for 'Pow' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:powc (ctx:powc)
Context propagation for 'PowConstExp' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:quadfn (ctx:quadfn)
Context propagation for 'QuadraticFunctionalConstraint' expression, see
cvt:pre:ctx:abs.
cvt:pre:ctx:round (ctx:round)
Context propagation for 'Round' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:sdpdotprod (ctx:sdpdotprod)
Context propagation for 'SDPDotProd' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:signpowc (ctx:signpowc)
Context propagation for 'SignpowConstExp' expression, see
cvt:pre:ctx:abs.
cvt:pre:ctx:sin (ctx:sin)
Context propagation for 'Sin' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:sinh (ctx:sinh)
Context propagation for 'Sinh' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:tan (ctx:tan)
Context propagation for 'Tan' expression, see cvt:pre:ctx:abs.
cvt:pre:ctx:tanh (ctx:tanh)
Context propagation for 'Tanh' expression, see cvt:pre:ctx:abs.
cvt:pre:disj2ind (disj2ind)
Absorb static disjunctions l || C, where C is a conditional comparison
used only there (or an AND of such), into indicator constraints !l ==>
C. This is how implications b==1 ==> C are received from AMPL. Bitwise
OR of the following values:
1 - Linear comparisons
2 - Quadratic comparisons
4 - Both disjuncts absorbable: absorb one into an indicator on the
other's result (if-else shape, complementarity)
8 - Comparisons x==k awaiting the unary encoding decision for x
(absorbed only if no encoding is chosen)
16 - Any AND of such comparisons (used only there) in positive context,
e.g., a disjunct (C1 && C2) of a multi-term disjunction: indicators on
the AND's result variable
32 - Static disjunctions l1 || .. || lm || (y1 && .. && yk) with the AND
used only there: clauses l1 || .. || lm || yj, without the AND's result
variable.
Requires cvt:pre:all=1. Default 11.
cvt:pre:eqbinary
0/1*: Preprocess reified equality comparison with a binary variable.
cvt:pre:eqresult
0/1*: Preprocess reified equality comparison's decidable cases.
cvt:pre:feastol (pre:feastol, pre:eps, pre:feastolabs, pre:epsabs)
Absolute tolerance to check variable and constraint bound contraditions.
Only warns if also pre:feastolrel is violated. See also sol:chk:feastol.
Default 1e-6.
cvt:pre:feastolrel (pre:feastolrel, pre:epsrel)
Relative tolerance to check variable and constraint bound
contradictions. Only warns if also pre:feastol is violated. See also
sol:chk:feastol. Default 1e-6.
cvt:pre:ineq2bndeq (ineq2bndeq)
0/1*: Preprocess reified inequality expr <(=) c, where c <)=(
lb(expr)+cvt:mip:eps, into expr == lb(expr), which works better on some
benchmarks/solvers.
cvt:pre:ineq2related (ineq2related, ineq2rel)
0/1*: Unify related reified inequalities: <=c, <c+cvt:mip:eps, >c,
>=c+cvt:mip:eps.
cvt:pre:ineqresult
0/1*: Preprocess reified inequality comparison's decidable cases.
cvt:pre:ineqrhs
0/1*: Preprocess reified inequality comparison's right-hand sides (round
for integer expression body).
cvt:pre:logistic (cvt:logistic)
0*/1: recognize logistic functions in the model, see acc:logistic.
cvt:pre:prod (cvt:prod)
Product preprocessing flags. Sum of a subset of the following bits:
1 - Quadratize higher-order products in the following order: integer
terms first, then real-valued ones; in each group, smaller-range terms
first.
2 - Logicalize products of 2 binary terms. Logicalizing means that the
product is converted to a conjunction. If the solver does not support it
natively (see acc:and), the conjunction is linearized.
4 - Logicalize products of >=3 binary terms.
Default: 7.
Bits 2 or 4 imply bit 1.
cvt:pre:signpow (cvt:signpow)
0*/1: recognize signpow() functions in the model, such as abs(x)*x, see
acc:signpow.
cvt:pre:sort (cvt:sort)
0/1*: Sort and eliminate duplicates in arguments of AND, OR, MIN, MAX.
Sort arguments of COUNT, ATLEAST, EXACTLY, ATMOST, NUMBEROF, ALLDIFF.
Can be necessary for some solvers.
cvt:pre:unnest (cvt:unnest, cvt:pre:inline, cvt:inline)
Inline nested expressions. Bitwise OR of the following values:
1 - AND/FORALL and OR/EXISTS expressions
2 - Linear subexpressions in algebraic constraints
4 - Linear and quadratic subexpressions in algebraic constraints
8 - MIN/MAX
16 - Algebraic subexpressions in indicator constraints.
See also option cvt:dvelim concerning only the input model. Default 31.
cvt:pre:vbnd (vbnd)
Comparisons x (cmp) c decided by the domain of x reuse an existing
binary instead of a new reified comparison. Bitwise OR of the following
values:
1 - Variable-bound constraints x >= L*b, x <= U*b with binary b (AMPL's
encoding of x in {0} union interval[L, U], or the user's), 0 <= c <= L:
reuse b or its negation
2 - Root disjunctions x <= a || x >= b (e.g., x == 0 || x >= L for x >=
0), a < c < b: reuse the comparison x >= b or its negation.
Default 3.
cvt:qp2passes (cvt:qp2pass, qp2passes, qp2pass)
0/1*: Parse sums of QP expressions in 2 passes. Usually faster.
cvt:quadcon (passquadcon)
0/1*: set to 0 to disable quadratic constraints. Synonym for
acc:quad..=0. Setting to 0 disables out-multiplication of quadratic
terms, then they are linearized.
cvt:quadobj (passquadobj)
0*/1: Pass quadratic objective terms to the solver. When 0, if the
solver accepts quadratic constraints, such a constraint will be created
with those, otherwise linearly approximated. With cvt:nlobj=0, ensures
the objective is linear.
cvt:socp (socpmode, socp)
Second-Order Cone recognition mode:
0 - Do not recognize SOCP forms
1 - Recognize from non-quadratic expressions only (sqrt, abs)
2 - Recognize from quadratic and non-quadratic SOCP forms. Helpful if
the solver does not recognize non-standard forms
Recognized SOCP forms can be further converted to (SOCP-standardized)
quadratic constraints, see cvt:socp2qc. Default: 0.
cvt:socp2qc (socp2qcmode, socp2qc)
Mode to convert recognized SOCP forms to SOCP-standardized quadratic
constraints:
0 - Do not convert
1 - Convert if no other cone types found, and not all original
quadratics could be recognized as SOC, in particular if the
objective is quadratic
2 - Always convert
Such conversion can be necessary if the solver does not accept a mix of
conic and quadratic constraints/objectives. Default: 2.
cvt:sos (sos)
0/1*: Whether to honor declared suffixes .sosno and .ref describing SOS
sets. Each distinct nonzero .sosno value designates an SOS set, of type
1 for positive .sosno values and of type 2 for negative values. The .ref
suffix contains corresponding reference values used to order the
variables.
cvt:sos2 (sos2)
0*/1: Whether to honor SOS2 constraints for nonconvex piecewise-linear
terms, using suffixes .sos and .sosref provided by AMPL. Currently under
rework; we recommend to switch off PL expression linearization in AMPL
(option pl_linearize 0).
cvt:uenc:negctx:max (uenc:negctx:max, cvt:uenc:negctx, uenc:negctx)
If cvt:uenc:ratio applies, max number of constants in comparisons
x==const in negative context (equivalently, x!=const in positive
context), where const!=lb(x) and const!=ub(x), to skip unary encoding of
x. Default 1.
Example:
var x in 1..9;
var y >=1 <=200;
s.t. Con: (x==9 || x==2 || x==6) ==> y >= 4;
With uenc:negctx<=1, this triggers unary encoding for x.
cvt:uenc:ratio (uenc:ratio)
Min ratio (ub-lb+1)/Nvalues to skip unary encoding for a variable x,
where Nvalues is the number of constants used in conditional comparisons
x==const. Instead, indicator constraints (or big-Ms) are used, if
uenc:negctx also applies. Default 0.
Example:
var x in 1..9;
var y >=1 <=200;
s.t. Con: y>3 ==> (x==2 || x==6 || x==5);
With uenc:ratio>3, this triggers unary encoding for x.
lim:conflicts (conflictlim, conflictlimit)
Limit on the number of conflicts; default: no limit.
lim:dettime (dettimelim, dettimelimit)
Limit on the deterministic time (an abstract, machine-independent
measure, which makes runs reproducible); default: no limit.
lim:mem (memlimit)
Limit on the memory used, in megabytes (default 10000). The solver stops
when it is reached.
lim:time (timelim, timelimit)
Limit on solve time (in seconds; default: no limit).
mip:bestbound (bestbound, return_bound)
Whether to return suffix .bestbound for the best known MIP dual bound on
the objective value:
0 - No (default)
1 - Yes.
The suffix is on the objective and problem and is -Infinity for
minimization problems and +Infinity for maximization problems if there
are no integer variables or if a dual bound is not available.
mip:gap (mipgap)
Relative gap between the best objective and the best bound at which to
stop (default 0).
mip:gapabs (mipgapabs)
Absolute gap between the best objective and the best bound at which to
stop (default 1e-4).
mip:plateau:absgaptol (mip:plateauabsgaptol, plateauabsgaptol)
If set (>0), also track the reported absolute MIP gap as progress for
mip:plateautime: the plateau timer resets whenever the absolute gap
shrinks by at least this amount. Default 0 (disabled).
mip:plateau:abstol (mip:plateauabstol, plateauabstol)
Minimum absolute objective improvement to reset the mip:plateautime
timer. Default 0 (any improvement resets the timer).
mip:plateau:log (mip:plateaulog, plateaulog)
Whether to print the current plateau status. Default 0 (silent).
mip:plateau:relgaptol (mip:plateaurelgaptol, plateaurelgaptol)
If set (>0), also track the reported relative MIP gap as progress for
mip:plateautime: the plateau timer resets whenever the relative gap
shrinks by at least this amount. Default 0 (disabled).
mip:plateau:reltol (mip:plateaureltol, plateaureltol)
Minimum relative objective improvement, as a fraction of the current
value, to reset the mip:plateautime timer. Default 0.
mip:plateau:time (mip:plateautime, plateautime)
Stop the MIP search if the incumbent objective (and, if
mip:plateauabsgaptol/mip:plateaurelgaptol are set, the MIP gap) has not
improved by at least mip:plateauabstol or mip:plateaureltol for this
many seconds. Default 0 (disabled).
mip:plateau:warmup (mip:plateauwarmup, plateauwarmup)
Grace period (in seconds) after the solve starts before mip:plateautime
is checked. Default 0.
mip:plateau:warmup:absgap (mip:plateauwarmupabsgap, plateauwarmupabsgap)
Absolute MIP gap to be reached before mip:plateautime is checked.
Default 0.
mip:plateau:warmup:relgap (mip:plateauwarmuprelgap, plateauwarmuprelgap)
Relative MIP gap to be reached before mip:plateautime is checked.
Default 0.
mip:return_gap (return_mipgap)
Whether to return mipgap suffixes or include mipgap values (|objectve -
.bestbound|) in the solve_message: sum of
1 - Return .relmipgap suffix (relative to |obj|)
2 - Return .absmipgap suffix (absolute mipgap)
4 - Suppress mipgap values in solve_message.
Default = 0. The suffixes are on the objective and problem. Returned
suffix values are +Infinity if no integer-feasible solution has been
found, in which case no mipgap values are reported in the solve_message.
mip:round (round)
Whether to round integer variables to integral values before returning
the solution, and whether to report that the solver returned noninteger
values for integer values: sum of
1 ==> Round nonintegral integer variables
2 ==> Modify solve_result
4 ==> Modify solve_message
Default = 0. Modifications that were or would be made are reported in
solve_result and solve_message only if the maximum deviation from
integrality exceeded mip:round_reptol.
mip:round_reptol (round_reptol)
Tolerance for reporting rounding of integer variables to integer values;
see "mip:round". Default = 1e-9.
obj:multi (multiobj)
Whether to use multi-objective optimization:
0 - Single objective, see option obj:no (default)
1 - Multi-objective, solver's native handling if available
2 - Multi-objective, force emulation
When obj:multi>0 and several objectives are present, suffixes
.objpriority, .objweight, .objreltol, and .objabstol on the objectives
are relevant. Objectives with greater .objpriority values (integer
values) have higher priority. Objectives with the same .objpriority are
weighted by .objweight, according to the option obj:multi:weight.
Objectives with positive .objabstol or .objreltol are allowed to be
degraded by lower priority objectives by amounts not exceeding the
.objabstol (absolute) and .objreltol (relative) limits.
Note that with solver's native handling (when obj:multi=1 and
supported), some solvers might have special rules for the tolerances,
especially for LP, and only allow linear objectives. See the solver
documentation and options cvt:quadobj, cvt:nlobj.
obj:multi:options (multiobjoptions)
0/1*: Regard multiobjective option suffixes which are objective suffixes
beginning with option_. Example: suffix option_timelim; let
_obj[2].option_timelim:=15;
obj:multi:stats (multiobjstats)
0*/1: Report multiobjective pass statistics in the following objective
suffixes:
* .objpass: index of the pass where this objective was solved, 0 if not
solved due to a stop in a previous pass
* .objpass_result: the solve_result of the pass where this objective was
solved; -1 if not
* .objpass_runtime, _mipgap, _objval, _objbound, _work, _itercount,
_nodecount, _opennodecount if available.
With MP's emulation (obj:multi=2), _objval and _objbound refer to the
blended pass objective in the sense of the first objective, and _runtime
is the wall-clock time of the pass including model updates; numeric
statistics are NaN if not available for a pass. If the solver's native
multiobjective mode does not report pass statistics, use obj:multi=2.
See also tech:stats.
obj:multi:weight (multiobjweight, obj:multi:weights, multiobjweights)
How to interpret each objective's weight sign:
1 - relative to the sense of the 1st objective
2 - relative to its own sense (default)
With the 1st option (legacy behaviour), negative .objweight for
objective i would make objective i's sense the opposite of the model's
1st objective. Otherwise, it would make objective i's sense the opposite
to its sense defined in the model.
obj:no (objno)
Objective to optimize:
0 - None
1 - First (default, if available)
2 - Second (if available), etc.
pre:solve (presolve)
Whether to use CP-SAT presolve:
0 - No
1 - Yes (default)
sol:chk:fail (chk:fail, checkfail)
Fail on MP solution check violations, with solve result 150.
sol:chk:feastol (sol:chk:eps, chk:eps, chk:feastol)
Absolute tolerance to check objective values', variable and constraint
bounds' violations. Only triggers if also sol:chk:feastolrel is
violated. See also pre:feastol. Default 1e-6.
sol:chk:feastolrel (sol:chk:epsrel, chk:epsrel, chk:feastolrel)
Relative tolerance to check objective values', variable and constraint
bounds' violations. Only triggers if also sol:chk:feastol is violated.
See also pre:feastol. Default 1e-6.
sol:chk:infeas (chk:infeas, checkinfeas)
Check even infeasible solution condidates, whenever solver reports them.
sol:chk:inttol (sol:chk:inteps, sol:inteps, chk:inttol)
Solution checking tolerance for variables' integrality. Default 1e-5.
sol:chk:mode (solcheck, checkmode, chk:mode)
Solution checking mode. Sum of a subset of the following bits:
1 - Check variable bounds and integrality.
2 - Check original model constraints, as well as any non-linear
expression values reported by the solver.
4 - Check intermediate auxiliary constraints (i.e., those which were
reformulated further).
8 - Check final auxiliary constraints sent to solver.
16 - Check objective values.
32, 64, 128, 256, 512 - similar, but non-linear expressions are
recomputed (vs using their values reported by the solver.)
*Experimental.* This is an idealistic check, because it does not
consider possible tolerances applied by the solver when computing
expression values.
Default: 1+2+512.
sol:chk:prec (chk:prec, chk:precision)
AMPL solution_precision option when checking: number of significant
digits.
sol:chk:round (chk:round, chk:rnd)
AMPL solution_round option when checking: round to this number of
decimals after comma (before comma if negative.)
sol:count (countsolutions)
0*/1: Whether to count the number of solutions and return it in the
".nsol" problem suffix.
sol:report_uncertain (report_uncertain_sol)
0/1*: whether to report objective value(s) in solve_message when
solve_result is '?' (unknown).
sol:stub (solstub, solutionstub)
Stub for solution files. If "solutionstub" is specified, found solutions
are written to files ("solutionstub & '1' & '.sol'") ... ("solutionstub
& Current.nsol & '.sol'"), where "Current.nsol" holds the number of
returned solutions. That is, file names are obtained by appending 1, 2,
... "Current.nsol" to "solutionstub".
tech:debug (debug)
0*/1: whether to assist testing & debugging, e.g., by outputting
auxiliary information (mostly via suffixes).
tech:logfile (logfile)
Log file name. The log is appended to it regardless of tech:outlev,
which only controls whether the log is also written to stdout.
tech:optionfile (optionfile, option:file)
Name of an AMPL solver option file to read (surrounded by 'single' or
"double" quotes if the name contains blanks). Lines that start with #
are ignored. Otherwise, each nonempty line should contain "name=value",
e.g., "lim:iter=500".
tech:outlev (outlev)
0*/1: Whether to write the CP-SAT search log to stdout.
tech:outlev_mp (outlev_mp)
0*/1: whether to print MP model information.
tech:params (params, parameters)
Additional CP-SAT parameters, in the protobuf text format of
SatParameters, applied after all other options. Example:
"params='linearization_level: 2 symmetry_level: 3'".
tech:seed (seed)
Random seed (default 1).
tech:stats (stats, tech:report_stats, solve_stats)
Whether to return solve statistics and timings; the information will be
stored in the problem suffixes: 'simplex_iterations',
'barrier_iterations', 'nodes' and possibly other solver-dependent
suffixes. A JSON representation of the information above is returned in
the problem suffix `stats`.
Note that timing information will also be included in the JSON
representation if tech:timing>0. Values:
0 - Do not report statistics (default)
1 - Report statistics in JSON format in the problem suffix 'stats'
2 - Report statistics in suffixes
3 - Report statistics both in suffixes and the suffix 'stats'.
See also obj:multi:stats.
tech:threads (threads)
How many search workers (threads) to use; default 0 ==> automatic
choice.
tech:timing (timing, tech:report_times, report_times)
0*/1/2: Whether to print and return timings for the run, all times are
wall times. If set to 1, return the solution times in the problem
suffixes 'time_solver', 'time_setup' and 'time', 'time'=
time_solver+time_setup+time_output is a measure of the total time spent
in the solver driver. If set to 2, return more granular times, including
'time_read', 'time_conversion' and 'time_output'.
tech:varbound (varbound)
Magnitude used for infinite variable bounds, which CP-SAT cannot handle
(default 1e12). Larger values may cause integer overflow in the CP-SAT
model.
tech:version (version)
Single-word phrase: report version details before solving the problem.
tech:wantsol (wantsol)
In a stand-alone invocation (no "-AMPL" on the command line), what
solution information to write. Sum of
1 - Write ".sol" file
2 - Primal variables to stdout
4 - Dual variables to stdout
8 - Suppress solution message.
tech:writegraph (cvt:writegraph, writegraph, exportgraph)
File to export conversion graph. Format: JSON Lines.
tech:writemodel (tech:writeprob, writeprob, writemodel, tech:exportfile)
Specifies files where to export the model before solving (repeat the
option for several files.) File name extensions can be ".lp[.7z]",
".mps", etc.
To write a model during iterative solve (e.g., with obj:multi=2), use
tech:writemodel:index.
tech:writemodel:index (tech:writeprob:index, writeprobindex, writemodelindex)
During iterative solve (e.g., with obj:multi=2), the iteration before
which to write solver model. 0 means before iteration is initialized;
positive value - before solving that iteration. Default 0.
tech:writemodelonly (justwriteprob, justwritemodel)
Specifies files where to export the model, no solving (option can be
repeated.) File extensions can be ".dlp", ".mps", etc.