BARONMP Options#
ampl: option solver baronmp; # change the solver
ampl: option baronmp_options 'option1=value1 option2=value2'; # specify options
ampl: solve; # solve the problem
Solver options obtained with $ baronmp -=.
BARONMP Optimizer Options for AMPL
--------------------------------------------
To set these options, assign a string specifying their values to the AMPL
option "baronmp_options". For example:
ampl: option baronmp_options 'mipgap=1e-6';
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:_expr
Solver acceptance level for all expressions, default 1:
0 - Not accepted, all expressions will be treated as flat constraints,
or redefined
1 - Accepted. See the individual acc:... options
acc:div
Solver acceptance level for 'DivConstraint' as expression, default 4:
0 - Not accepted natively, automatic redefinition will be attempted
3 - Accepted but automatic redefinition will be used where possible
4 - Accepted natively and preferred
acc:exp
Solver acceptance level for 'ExpConstraint' as either constraint or
expression, default 4:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted as constraint but automatic redefinition will be used
where possible
2 - Accepted as constraint natively and preferred
3 - Accepted as expression but automatic redefinition will be used
where possible
4 - Accepted as expression natively and preferred
acc:expa (acc:expA)
Solver acceptance level for 'ExpAConstraint' as either constraint or
expression, default 4:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted as constraint but automatic redefinition will be used
where possible
2 - Accepted as constraint natively and preferred
3 - Accepted as expression but automatic redefinition will be used
where possible
4 - Accepted as expression 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:linfunccon
Solver acceptance level for 'LinearFunctionalConstraint' as expression,
default 4:
0 - Not accepted natively, automatic redefinition will be attempted
3 - Accepted but automatic redefinition will be used where possible
4 - 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:log
Solver acceptance level for 'LogConstraint' as either constraint or
expression, default 4:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted as constraint but automatic redefinition will be used
where possible
2 - Accepted as constraint natively and preferred
3 - Accepted as expression but automatic redefinition will be used
where possible
4 - Accepted as expression natively and preferred
acc:loga (acc:logA)
Solver acceptance level for 'LogAConstraint' as either constraint or
expression, default 4:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted as constraint but automatic redefinition will be used
where possible
2 - Accepted as constraint natively and preferred
3 - Accepted as expression but automatic redefinition will be used
where possible
4 - Accepted as expression natively and preferred
acc:nlassigneq
Solver acceptance level for 'NLAssignEQ' 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:nlassignge
Solver acceptance level for 'NLAssignGE' 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:nlassignle
Solver acceptance level for 'NLAssignLE' 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:nlcon (acc:nlalgcon)
Solver acceptance level for 'NLConstraint' 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:powconstexp
Solver acceptance level for 'PowConstExpConstraint' as either constraint
or expression, default 4:
0 - Not accepted natively, automatic redefinition will be attempted
1 - Accepted as constraint but automatic redefinition will be used
where possible
2 - Accepted as constraint natively and preferred
3 - Accepted as expression but automatic redefinition will be used
where possible
4 - Accepted as expression natively and preferred
acc:quadeq
Solver acceptance level for 'QuadConEQ' 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:quadfunccon
Solver acceptance level for 'QuadraticFunctionalConstraint' as
expression, default 4:
0 - Not accepted natively, automatic redefinition will be attempted
3 - Accepted but automatic redefinition will be used where possible
4 - Accepted natively and preferred
acc:quadge
Solver acceptance level for 'QuadConGE' 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:quadle
Solver acceptance level for 'QuadConLE' 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:quadrange (acc:quadrng)
Solver acceptance level for 'QuadConRange' 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:deltaa (deltaa)
Adjustment parameter for delta values.
alg:deltar (deltar)
Relative delta adjustment.
alg:deltat (deltat)
Time-based delta adjustment.
alg:deltaterm (deltaterm)
Delta termination criterion.
alg:epsa (epsa)
EpsA convergence tolerance (default 1e-6). BARON stops if the current
function value f satisfies abs(f - L) <= epsa, where L is the currently
best available bound on f.
alg:epsr (epsr)
BARON's EpsR convergence tolerance (default 1e-9). BARON stops if the
current function value f satisfies abs(f - L) <= abs(L*epsr), where L is
the currently best available bound on f.
alg:firstfeas (firstfeas)
If set to 1, BARON will terminate once it finds numsol feasible
solutions, irrespective of solution quality. Default is 0, meaning that
BARON will search for the *best* numsol feasible solutions.
alg:firstloc (firstloc)
If set to 1, BARON will terminate once it finds a local optimum,
irrespective of solution quality. Default is 0, meaning that BARON will
search for the best numsol feasible solutions.
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) (default)
2 - Yes (for LP: ignoring the incoming alg:basis, if any.)
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:expcones (expcones)
0*/1: Recognize exponential cones.
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. Default:
1e-4.
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: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:pre:all
0/1*: Set to 0 to disable most presolve in the flat converter.
cvt:pre:eqbinary
0/1*: Preprocess reified equality comparison with a binary variable.
cvt:pre:eqresult
0/1*: Preprocess reified equality comparison's boolean result bounds.
cvt:pre:unnest
0/1*: Inline nested expressions, currently Ands/Ors.
cvt:prod (cvt:pre: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: 1+4. That is, 2-term binary products which are not part of a
higher-order binary product, are not logicalized by default.
Bits 2 or 4 imply bit 1.
cvt:quadcon (passquadcon)
Convenience option. Set to 0 to disable quadratic constraints. Synonym
for acc:quad..=0. Currently this disables out-multiplication of
quadratic terms, then they are linearized.
cvt:quadobj (passquadobj)
0/1*: Pass quadratic objective terms to the solver. If the solver
accepts quadratic constraints, such a constraint will be created with
those, otherwise linearly approximated.
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: 2.
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.
cvt:uenc:negctx:max (uenc:negctx:max, uenc:negctx)
If cvt:uenc:ratio applies, max number of constants in comparisons
x==const in negative context (equivalently, x!=const in positive
context) to skip UEnc(x). Default 1.
cvt:uenc:ratio (uenc:ratio)
Min ratio (ub-lb)/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.
lim:iter (iterlimit, maxiter)
Maximum number of iterations.
lim:time (timelim, timelimit, maxtime)
Maximum time in seconds (default 1000).
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: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 not allow quadratic objectives. See the solver
documentation.
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.
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. Default 1e-6.
sol:chk:feastolrel (sol:chk:epsrel, chk:epsrel, chk:feastolrel)
Relative tolerance to check objective values, variable and constraint
bounds. 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: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:barstats (barstats)
Report detailed BARON statistics.
tech:cplexlibname (cplexlibname)
If used, specifies the path to cplex libraries
tech:debug (debug)
0*/1: whether to assist testing & debugging, e.g., by outputting
auxiliary information.
tech:keepsol (keepsol)
Keep BARON's solution files.
tech:lpsolver (lpsolver)
Choice of LP solver, which matters mainly when there are integer
variables: one of cbc (default), cplex, or xpress. The last two must be
suitably licensed to be used.
tech:lsolmsg (lsolmsg)
Show solution messages for lsolver.
tech:lsolver (lsolver)
Local nonlinear solver that BARON should call.
tech:nlpsolver (nlpsol, nlpsolver)
Local nonlinear solvers BARON is allowed to use: sum (mod 16) of
| 1 - IPOPT (builtin)
| 2 - FilterSD (builtin)
| 4 - FilterSQP (builtin)
| 8 - lsolver (if lsolver=... is specified)
Default 0 - allow all.
tech:numsol (numsol)
Number of near optimal solutions to find. Default = 1; values > 1 imply
keepsol and cause suffix .numsol on the objective and problem to be
returned.
tech:objbound (objbound)
Return suffixes .obj_lb and .obj_ub on the problem and objective with
Baron's final lower and upper bounds on the objective value
tech:objno (objno)
Objective number (default: 1).
tech:optfile (optfile)
Name of BARON option file (not required). If given, the file should
contain name-value pairs, one per line, with the name and value
separated by a blank, a colon, or an equal sign, possibly surrounded by
white space. The names and possible values are summarized in section 7
of the BARON user manual (baron_manual.pdf). Empty lines and lines that
start with # are ignored.
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:optionnative (optionnative, optnative, tech:param)
General way to specify values of both documented and undocumented Baron
parameters; value should be a quoted string (delimited by ' or ")
containing a parameter name, a space, and the value to be assigned to
the parameter.
tech:outlev (outlev)
Output verbosity level.
tech:overwrite (overwrite)
If set, overwrite the files in the scratch directory.
tech:prfreq (prfreq)
Report progress every prfreq nodes (default 1e6).
tech:prloc (prloc)
Whether to report local searches:
0 - No (default)
1 - Yes.
tech:problem (problem)
Problem name printed in logfile.
tech:prtime (prtime)
Report progress every prtime seconds (default 30).
tech:scratch (scratch)
Directory for temporary files; if set to 'local' it uses a subdirectory
of the NL file location with the NL file name
tech:seed (seed)
Initial seed for random number generation, must be a positive integer
(default 19631963).
tech:sumfile (sumfile)
Name of summary file.
tech:threads (threads)
Maximum number of threads to use (default 1 when integer variables are
present)
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:trace (trace)
Name of BARON trace file.
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.
tech:writesolution (writesol, writesolution)
Specifies the names of files where to export the solution and/or other
result files in solver's native formats. Option can be repeated. File
name extensions can be ".sol[.tar.gz]", ".json", ".bas", ".ilp", etc.
tech:xpresslibname (xpresslibname)
If used, specifies the path to xpress libraries