Provided by: toulbar2_1.2.1+dfsg-0.1_amd64 
NAME
toulbar2 - exactly solves discrete optimization problems on graphical models
SYNOPSIS
toulbar2 [options] file
DESCRIPTION
toulbar2 solves discrete optimization problems defined by a graphical model including Cost Function
Networks (solving the Weighted Constraint Satisfaction Problem), Markov Random Fields (solving Maximum A
Posteriori or MAP/MRF), Bayesian Networks (solving Maximum Probability Explanation or MPE/BN), Quadratic
Pseudo Boolean Optimization Problems (QPBO or MAXCUT), Partial Weighted Maximum Satisfiability...
OPTIONS
GENERAL CONTROL
-a=[integer]
Finds at most a given number of solutions with a cost strictly lower than the initial upper bound
and stops, or if no integer is given, finds all solutions (or counts the number of zero-cost
satisfiable solutions in conjunction with BTD).
-agap=[decimal]
Stop search if the absolute optimality gap reduces under the given value (provides solutions with
a guaranteed absolute approximation).
-D Approximate zero-cost solution count with BTD.
-logz Computes the log of probability of evidence (i.e. log partition function or log(Z) or PR task).
Restricted to stochastic graphical models (.uai format).
-seed=[integer]
Initializes the pseudo-random generator used inside toulbar2 with a fixed non-negative integer
argument. A negative argument instead specifies that the pseudo-random generator be seeded by
current time (default value is 1).
--stdin=[format]
Indicates that the problem should be read from the standard input instead of a file (default
format is cfn). Eg. cat example.uai | toulbar2 --stdin=uai
-timer=[integer]
Gives a cpu-time limit in seconds. Toulbar2 will stop after the specified amount of CPU time has
been consumed. The time limit is a CPU user time limit, not wall clock time limit.
PREPROCESSING
-nopre Deactivates all preprocessing options (equivalent to -e: -p: -t: -f: -dec: -n: -mst: -dee:
-trws:).
-p=[integer]
Preprocessing only: activates variable elimination of variables of degree less than or equal to
the given value (default value is -1, with no elimination performed).
-t=[integer]
Preprocessing only: simulates restricted path consistency by adding ternary cost functions on
triangles of binary cost functions within a given maximum space limit (in MB).
-f=[integer]
Preprocessing only: variable elimination of functional (f=1) (resp. bijective (f=2)) variables
(default value is 1).
-dec Preprocessing only: pairwise decomposition of cost functions with arity larger than 3 into smaller
arity cost functions (default: activated).
-n=[integer]
Preprocessing only: projects n-ary cost functions on all binary cost functions if n is lower than
the given value (default value is 10).
-mst Find a maximum spanning tree ordering for DAC.
-M=[integer]
Apply the Min Sum Diffusion algorithm (default is off, with a number of iterations of 0).
INITIAL UPPER BOUNDING
-ub=[decimal]
Gives a primal (upper in minimization mode, lower otherwise) bound on cost that a solution must
satisfies. If the file specifies a primal bound too, the tightest of the two bounds is used. A
tight primal bound can accelerate search or be used in conjunction with -a to find all solutions
of sufficient quality.
-l=[integer]
Activate limited discrepancy search. Use a negative value to stop search after the given absolute
number of discrepancies have been explored (discrepancy bound = 4 by default).
-L=[integer]
Activate randomized (quasi-random variable ordering) search with restart (maximum number of nodes
= 10000 by default).
-i=["string"]
Use initial upper bound found by INCOP local search solver. The string parameter is optional,
using "0 1 3 idwa 100000 cv v 0 200 1 0 0" by default with the following meaning:
stoppinglowerbound randomseed nbiterations method nbmoves neighborhoodchoice neighborhoodchoice
minnbneighbors maxnbneighbors neighborhoodchoice autotuning tracemode.
-pils=["string"]
Use initial upper bound found by PILS local search solver. The string parameter is optional,
using "3 0 0.333 100 500 10000 0.1 0.5 0.1 0.1" by default with the following meaning: nbruns
perturb_mode perturb_strength flatMaxIter nbEvalHC nbEvalMax strengthMin strengthMax incrFactor
decrFactor.
-x=[(,i=a)*]
Assigns variable of index i to value a (multiple assignments are separated by a comma and no
space). Without any argument, a complete assignment, used as initial upper bound and as a value
orderin heuristic, is read from default file "sol" or from a filename given directly as an
additional input filename with ".sol" extension and without -x.
TREE SEARCH ALGORITHMS AND TREE DECOMPOSITION SELECTION
-hbfs=[integer]
Use hybrid best-first search, restarting from the root after a given number of backtracks (default
value is 10000).
-open=[integer]
Set hybrid best-first search limit on the number of stored open nodes (default value is -1, no
limit).
-B=[integer]
Use (0) DFBB, (1) BTD, (2) RDS-BTD, (3) RDS-BTD with path decomposition instead of tree
decomposition (default value is 0).
-O=[filename]
Read a variable elimination order from a file in order to build a tree decomposition (if BTD-like
and/or variable elimination methods are used). The order is also used as a DAC ordering.
-O=[negativeinteger]
Build a tree decomposition (if BTD-like and/or variable elimination methods are used) and also a
compatible DAC ordering using either:
(-1) maximum cardinality search ordering
(-2) minimum degree ordering
(-3) minimum fill-in ordering,
(-4) maximum spanning tree ordering (see -mst),
(-5) reverse Cuthill-Mckee ordering,
(-6) approximate minimum degree ordering.
If not specified, then the order in which variables appear in the problem file is used.
-j=[integer]
Splits large clusters into a chain of smaller embedded clusters with a number of proper variables
less than this number (use options "-B=3 -j=1 -svo -k=1" for pure RDS, use value 0 for no
splitting) (default value is 0).
-r=[integer]
Set a limit on the maximum cluster separator size (merge cluster with its father otherwise, use a
negative value for no limit, default value is -1).
-X=[integer]
Set a limit on the minimum number of proper variables in a cluster (merge cluster with its father
otherwise, use a zero for no limit, default value is 0).
-E=[float]
Merges leaf clusters with their fathers if small local treewidth (in conjunction with option "-e"
and positive threshold value) or a ratio of number of separator variables by number of cluster
variables is above a given threshold (in conjunction with option "-vns") (default value is 0).
-R=[integer]
Choose a specific cluster number as a root cluster.
-I=[integer]
Solve only a specific rooted cluster subtree (with RDS-BTD only).
VNS SEARCH
-vns unified decomposition guided variable neighborhood search (a problem decomposition can be given as
*.dec, *.cov, or *.order input files or using tree decomposition options such as -O).
-vnsini=[integer]
Initial solution for VNS-like methods found (-1) at random, (-2) min domain values, (-3) max
domain values, (-4) first solution found by a complete method, (k=0 or more) tree search with k
discrepancy max (-4 by default).
-ldsmin=[integer]
Minimum discrepancy for VNS-like methods (1 by default).
-ldsmax=[integer]
Maximum discrepancy for VNS-like methods (number of problem variables multiplied by maximum domain
size -1 by default).
-ldsinc=[integer]
Discrepancy increment strategy for VNS-like methods using (1) Add1, (2) Mult2, (3) Luby operator
(2 by default).
-kmin=[integer]
Minimum neighborhood size for VNS-like methods (4 by default).
-kmax=[integer]
Maximum neighborhood size for VNS-like methods (number of problem variables by default).
-kinc=[integer]
Neighborhood size increment strategy for VNS-like methods using (1) Add1, (2) Mult2, (3) Luby
operator (4) Add1/Jump (4 by default).
-best=[integer]
Stop VNS-like methods if a better solution is found (default value is 0).
NODE PROCESSING & BOUNDING OPTIONS
-e=[integer]
Perform "on the fly" variable elimination of variable with small degree (less than or equal to a
specified value. Default is 3, creating a maximum of ternary cost functions).
-k=[integer]
Set the soft local consistency level enforced at preprocessing and at each node during search:
0: Node Consistency with Strong Node Inverse Consistency for global cost functions,
1: Generalized Arc Consistency
2: Directed Generalized Arc Consistency
3: Full Directed Generalized Arc Consistency
4: (weak) Existential Directed Generalized Arc Consistency
Default value is 4.
-A=[integer]
Enforce Virtual Arc Consistency at each search node with a search depth less than the given value
(default value is 0 which enforces VAC only at root node).
-T=[decimal]
Threshold cost value for VAC (default value is 1).
-P=[decimal]
Threshold cost value for VAC during the preprocessing phase (default value is 1).
-C=[float]
Multiplies all costs internally by this number when loading the problem (default value is 1).
-S Preprocessing only: performs singleton consistency (only in conjunction with option "-A").
-trws=[float]
Preprocessing only: enforce TRW-S until a given precision is reached (default value is 0.00001).
--trws-n-iters=[integer]
Preprocessing only: enforce at most N iterations of TRW-S (default value is 1000).
--trws-n-iters-no-change=[integer]
Preprocessing only: stop TRW-S when N iterations did not change the lower bound up the given
precision (default value is 5, -1=never).
--trws-n-iters-compute-ub=[integer]
Preprocessing only: computes UB every N steps in TRW-S (default value is 100).
-dee=[integer]
Enforce restricted dead-end elimination, or value pruning by dominance rule from EAC value (dee>=1
and dee<=3) and soft neighborhood substitutability, in preprocessing (dee=2 or dee=4) or during
search (dee=3). Default value is 1.
-o Ensures an optimal worst-case time complexity of Directed and Existential Arc Consistency (can be
slower in practice).
BRANCHING, VARIABLE & VALUE ORDERING
-svo Use a static variable ordering heuristic. The variable order used will be the same order as the
DAC order.
-b Use binary branching (as a default) instead of k-ary branching. Uses binary branching for
interval domains and small domains and dichotomic branching for large enumerated domains (see
option -d).
-c Use binary branching with last conflict backjumping variable ordering heuristic.
-q=[integer]
Use weighted degree variable ordering heuristic if the number of cost functions is less than the
given value (default value is 10000).
-var=[integer]
Searches by branching only on the first [given value] decision variables, assuming the remaining
variables are intermediate variables that will be completely assigned by the decision variables
(use a zero if all variables are decision variables). Default value is 0.
-m=[integer]
Use a variable ordering heuristic that preferably selects variables such that the sum of the mean
(m=1) or median (m=2) cost of all incident cost functions is maximum (in conjunction with weighted
degree heuristic -q). Default value is 0: unused.
-d=[integer]
Searches using dichotomic branching. The default d=1 splits domains in the middle of domain range
while d=2 splits domains in the middle of the sorted domain based on unary costs.
-sortd Sort domains in preprocessing based on increasing unary costs (works only for binary CFN).
-solr Use solution-based phase saving as a value ordering heuristic (default option).
-V VAC-based value ordering heuristic (default option, only in conjunction with option "-A").
CONSOLE OUTPUT
-help Show default help message that toulbar2 prints when it gets no argument.
-v=[integer]
Set the verbosity level (default 0).
-Z=[integer]
Debug mode (save problem at each node if verbosity option -v=num>= 1 and -Z=num>=3).
-s=[integer]
Shows each solution found during search. The solution is printed on one line. The default -s=1
gives the value (integer) of each variable successively in increasing order of definition in the
model file. For -s=2, the value name is used instead, for -s=3, variable name=valuename is
printed instead.
FILE OUTPUT
-w=[filename]
Writes last solution found in the specified filename (or "sol" if no parameter is given). The
current directory is used as a relative path.
-z=[filename]
Saves problem in wcsp format in filename (or "problem.wcsp" if no parameter is given).
Writes also the graphviz .dot file and the degree distribution of the input problem.
-z=[integer]
1: saves original instance (by default), 2: saves
after preprocessing (this option can be used in combination with -z=filename).
PROBABILITY REPRESENTATION AND NUMERICAL CONTROL
-precision=[integer]
Probability/real log10 precision conversion factor (a power of ten) for representing probabilities
as fixed decimal point numbers. Default value is 7.
-epsilon=[float]
Approximation factor for computing the partition function (default value is 1000 representing
epsilon=1/1000).
-qpmult=[double]
Coefficient multiplier for quadratic terms when reading qpbo format (default value is 2).
RANDOM PROBLEM GENERATION
-random=[benchprofile]
Benchmark profile must be specified as follows, where n and d are respectively the number of
variable and the maximum domain size of the random problem.
bin-{n}-{d}-{t1}-{p2}-{seed}
t1 is the tightness in percentage of random binary cost functions
p2 is the number of binary cost functions to include
the seed parameter is optional
binsub-{n}-{d}-{t1}-{p2}-{p3}-{seed} binary random submodular cost functions
t1 is the tightness in percentage of random cost functions
p2 is the number of binary cost functions to include
p3 is the percentage of submodular cost functions among p2 cost functions (plus 10
permutations of two randomly-chosen values for each domain).
tern-{n}-{d}-{t1}-{p2}-{p3}-{seed}
p3 is the number of ternary cost functions
nary-{n}-{d}-{t1}-{p2}-{p3}...-{pn}-{seed}
pn is the number of n-ary cost functions
salldiff-{n}-{d}-{t1}-{p2}-{p3}...-{pn}-{seed}
pn is the number of salldiff global cost functions (p2 and p3 still being used for
the number of random binary and ternary cost functions). salldiff can be replaced by
gcc or regular keywords with three possible forms ( e.g., sgcc, sgccdp, wgcc).
FILE FORMATS
toulbar2 can read .cfn, .wcsp, .uai, .LG, .cnf, .wcnf, .qpbo, .pre, .bep files. The files can be
compressed with gzip or xz (e.g., .cfn.gz or .cfn.xz, except for pre and bep formats). See the full user
documentation for a description of these file formats.
SEE ALSO
A more complete user documentation should be available on your system, in
/usr/share/doc/toulbar2/userdoc.pdf or can be otherwise downloaded from http://miat.inrae.fr/toulbar2.
AUTHORS
See https://github.com/toulbar2/toulbar2
TOULBAR2(1)