- Spot-announce

Spot 2.8.3 released
by Alexandre Duret-Lutz 06 Nov '19

06 Nov '19

We are happy to announce the release of Spot 2.8.3 This release mainly works around an issue in recent GraphViz releases, causing cropped automata in Jupyter notebooks. (If you do not use Spot in Jupyter notebooks, there is little point in updating.) You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.8.3.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. Please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.8.3 (2019-11-06) Build: - Minor portabilities improvements with C++17 deprecations. Python: - Doing "import spot.foo" will now load any spot-extra/foo.py on Python's search path. This can be used to install third-party packages that want to behave as plugins for Spot. - Work around GraphViz bug #1605 in Jupyter notebooks. https://gitlab.com/graphviz/graphviz/issues/1605 -- Alexandre Duret-Lutz

1 0

Spot 2.8.2 released
by Alexandre Duret-Lutz 28 Sep '19

28 Sep '19

We are happy to announce the release of Spot 2.8.2 This release contains many minor fixes; mostly portability issues. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.8.2.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. Please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.8.2 (2019-09-27) Command-line tools: - ltl2tgba and ltldo learned a --negate option. Bugs fixed: - Calling "autfilt --dualize" on an alternating automaton with transition-based acceptance and universal initial states would fail with "set_init_state() called with nonexisting state". - The numbering of nodes in the AIGER output of ltlsynt was architecture dependent. - Various compilation issues. In particular, this release is the first one that can be compiled (and pass tests) on a Raspberry PI. -- Alexandre Duret-Lutz

1 0

Spot 2.8.1 released
by Alexandre Duret-Lutz 18 Jul '19

18 Jul '19

We are happy to announce the release of Spot 2.8.1 This release one important bug fix to ltlcross, and a few other minor addition. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.8.1.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.8.1 (2019-07-18) Command-line tools: - genltl learned --pps-arbiter-standard and --pps-arbiter-strict. - ltlcross and autcross have learned a new option -q (--quiet) to remain quiet until an error is found. This helps for instance in scenarios where multiple instances of ltlcross/autcross are run in parallel (using "xargs -P" or "GNU Parallel", for instance). See https://spot.lrde.epita.fr/ltlcross.html#parallel for examples. Bugs fixed: - When complement() was called with an output_aborter, it could return an alternating automaton on large automata. This in turn caused ltlcross to emit errors like "remove_alternation() only works with weak alternating automata" or "product() does not support alternating automata". - Work around Emacs bug #34341 when rebuilding documentation on a system with Emacs <26.3, GNU TLS >= 3.6, and without ESS or with an obsolete org-mode installed. -- Alexandre Duret-Lutz

1 0

Spot 2.8 released
by Alexandre Duret-Lutz 10 Jul '19

10 Jul '19

We are happy to announce the release of Spot 2.8 Spot is a library of algorithms for manipulating LTL formulas and omega-automata objects (as commonly used in model checking). This release contains code contributed by Clément Gillard and myself. A detailed list of new features is given at the end of this email. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.8.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. Note that since Debian 10 ("Buster") was released a few days ago, the "stable" Debian packages we distribute are now built for Buster. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.8 (2019-07-10) Command-line tools: - autfilt learned --highlight-accepting-run=NUM to highlight some accepting run with color NUM. - ltldo, ltlcross, and autcross are now preferring posix_spawn() over fork()+exec() when available. - ltlcross has new options --determinize-max-states=N and --determinize-max-edges=M to restrict the use of determinization-based complementation to cases where it produces automata with at most N states and M edges. By default determinization is now attempted up to 500 states and 5000 edges. This is an improvement over the previous default where determinization-based complementation was not performed at all, unless -D was specified. - ltlcross will now skip unnecessary cross-checks and consistency-checks (they are unnecessary when all automata could be complemented and statistics were not required). - genaut learned --m-nba=N to generate Max Michel's NBA familly. (NBAs with N+1 states whose determinized have at least N! states.) - Due to some new simplification of parity acceptance, the output of "ltl2tgba -P -D" is now using a minimal number of colors. This means that recurrence properties have an acceptance condition among "Inf(0)", "t", or "f", and persistance properties have an acceptance condition among "Fin(0)", "t", or "f". - ltldo and ltlcross learned shorthands to call the tools ltl2na, ltl2nba, and ltl2ngba from Owl 19.06. Similarly, autcross learned a shorthand for Owl's dra2dpa. Documentation: - https://spot.lrde.epita.fr/tut90.html is a new file that explains the purpose of the spot::bdd_dict object. Library: - Add generic_accepting_run() as a variant of generic_emptiness_check() that returns an accepting run in an automaton with any acceptance condition. - twa::accepting_run() and twa::intersecting_run() now work on automata using Fin in their acceptance condition. - simulation-based reductions have learned a trick that sometimes improve transition-based output when the input is state-based. (The automaton output by 'ltl2tgba -B GFa | autfilt --small' now has 1 state instead of 2 in previous versions. Similarly, 'ltldo ltl2dstar -f 'GFa -> GFb' | autfilt --small' produces 1 state instead of 4.) - simulation-based reductions hae learned another trick to better merge states from transiant SCCs. - acc_cond::top_disjuncts() and acc_cond::top_conjuncts() can be used to split an acceptance condition on the top-level & or |. These methods also exist in acc_cond::acc_code. - minimize_obligation() learned to work on very weak automata even if the formula or negated automaton are not supplied. (This allows "autfilt [-D] --small" to minimize very-weak automata whenever they are found to represent obligation properties.) - There is a new spot::scc_and_mark_filter objet that simplifies the creation of filters to restrict spot::scc_info to some particular SCC while cutting new SCCs on given acceptance sets. This is used by spot::generic_emptiness_check() when processing SCCs recursively, and makes it easier to write similar code in Python. - print_dot has a new option 'g', to hide edge labels. This is helpful to display automata as "graphs", e.g., when illustrating algorithms that do not care about labels. - A new complement() function returns complemented automata with unspecified acceptance condition, allowing different algorithms to be used. The output can be alternating only if the input was alternating. - There is a new class output_aborter that is used to specify upper bounds on the size of automata produced by some algorithms. Several functions have been changed to accept an output_aborter. This includes: * tgba_determinize() * tgba_powerset() * minimize_obligation() * minimize_wdba() * remove_alternation() * product() * the new complement() * the postprocessor class, via the "det-max-state" and "det-max-edges" options. - SVA's first_match operator can now be used in SERE formulas and that is supported by the ltl_to_tgba_fm() translation. See doc/tl/tl.pdf for the semantics. *WARNING* Because this adds a new operator, any code that switches over the spot::op type may need a new case for op::first_match. Furthermore, the output of "randltl --psl" will be different from previous releases. - The parser for SERE learned to recognize the ##n and ##[i:j] operators from SVA. So {##2 a ##0 b[+] ##1 c ##2 e} is another way to write {[*2];a:b[+];c;1;e}. The syntax {a ##[i:j] b} is replaced in different ways depending on the values of i, a, and b. The formula::sugar_delay() function implements this SVA operator in terms of the existing PSL operators. ##[+] and ##[*] are sugar for ##[1:$] and ##[0:$]. - The F[n:m] and G[n:m] operators introduced in Spot 2.7 now support the case where m=$. - spot::relabel_apply() makes it easier to reverse the effect of spot::relabel() or spot::relabel_bse() on formula. - The LTL simplifier learned the following rules: F(G(a | Fb)) = FGa | GFb (if option "favor_event_univ") G(F(a | Gb)) = GFa | FGb (if option "favor_event_univ") F(G(a & Fb) = FGa & GFb (unless option "reduce_size_strictly") G(F(a & Gb)) = GFa & FGb (unless option "reduce_size_strictly") GF(f) = GF(dnf(f)) (unless option "reduce_size_strictly") FG(f) = FG(cnf(f)) (unless option "reduce_size_strictly") (f & g) R h = f R h if h implies g (f & g) M h = f M h if h implies g (f | g) W h = f W h if g implies h (f | g) U h = f U h if g implies h Gf | F(g & eventual) = f W (g & eventual) if !f implies g Ff & G(g | universal) = f M (g | universal) if f implies !g f U (g & eventual) = F(g & eventual) if !f implies g f R (g | universal) = G(g | universal) if f implies !g - cleanup_parity() and colorize_parity() were cleaned up a bit, resulting in fewer colors used in some cases. In particular, colorize_parity() learned that coloring transitiant edges does not require the introduction of a new color. - A new reduce_parity() function implements and generalizes the algorithm for minimizing parity acceptance by Carton and Maceiras (Computing the Rabin index of a parity automaton, 1999). This is a better replacement for cleanup_parity() and colorize_parity(). See https://spot.lrde.epita.fr/ipynb/parity.html for examples. - The postprocessor and translator classes are now using reduce_parity() for further simplifications. - The code for checking recurrence/persistence properties can also use the fact the reduce_parity() with return "Inf(0)" (or "t" or "f") for deterministic automata corresponding to recurrence properties, and "Fin(0)" (or "t" or "f") for persistence properties. This can be altered with the SPOT_PR_CHECK environment variable. Deprecation notices: - The virtual function twa::intersecting_run() no longuer takes a second "from_other" Boolean argument. This is a backward incompatibility only for code that overrides this function in a subclass. For backward compatibility with programs that simply call this function with two argument, a non-virtual version of the function has been introduced and marked as deprecated. - The spot::acc_cond::format() methods have been deprecated. These were used to display acceptance marks, but acceptance marks are unrelated to acceptance conditions, so it's better to simply print marks with operator<< without this extra step. Bugs fixed: - The gf_guarantee_to_ba() is relying on an inplace algorithm that could produce a different number of edges for the same input in two different transition order. - A symmetry-based optimization of the LAR algorithm performed in spot::to_parity() turned out to be incorrect. The optimization has been removed. "ltlsynt --algo=lar" is the only code using this function currently. -- Alexandre Duret-Lutz

1 0

Spot 2.7.5 released
by Alexandre Duret-Lutz 05 Jun '19

05 Jun '19

We are happy to announce the release of Spot 2.7.5 This maintenance release fixing a few minor issues. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.7.5.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.7.5 (2019-06-05) Build: - Although the Python bindings in this release are still done with Swig3.0, the code has been updated to be compatible with Swig4.0. Library: - print_dot will replace labels that have more 2048 characters by a "(label too long)" string. This works around a limitation of GraphViz that aborts when some label exceeds 16k characters, and also helps making large automata more readable. Bugs fixed: - spot::translator was not applying Boolean sub-formula rewritting by default unless a spot::option_map was passed. This caused some C++ code for translating certains formulas to be noticeably slower than the equivalent call to the ltl2tgba binary. - The remove_ap algorithm was preserving the "terminal property" of automata, but it is possible that a non-terminal input produces a terminal output after some propositions are removed. -- Alexandre Duret-Lutz

1 0

Spot 2.7.4 released
by Alexandre Duret-Lutz 27 Apr '19

27 Apr '19

We are happy to announce the release of Spot 2.7.4 This maintenance release contains only some bug fixes. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.7.4.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.7.4 (2019-04-27) Bugs fixed: - separate_sets_here() (and therefore autfilt --separate-sets) could loop infinitely on some inputs. - In some situation, ltl2tgba -G could abort with "direct_simulation() requires separate Inf and Fin sets". This was fixed by teaching simulation-based reductions how to deal with such cases. - The code for detecting syntactically stutter-invariant PSL formulas was incorrectly handling the ";" operator, causing some stutter-sensitive formulas to be flagged a stutter-invariant. -- Alexandre Duret-Lutz

1 0

Spot 2.7.3 released
by Alexandre Duret-Lutz 19 Apr '19

19 Apr '19

We are happy to announce the release of Spot 2.7.3 This maintenance release contains only bug fixes and documentation updates. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.7.3.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.7.3 (2019-04-19) Bugs fixed: - When processing CSV files with MSDOS-style \r\n line endings, --stats would output the \r as part of the %> sequence instead of ignoring it. - Fix serious typo in removel_alternation() causing incorrect output for some VWAA. Bug introduced in Spot 2.6. Documentation: - Multiple typos and minor updates. -- Alexandre Duret-Lutz

1 0

Spot 2.7.2 released
by Alexandre Duret-Lutz 17 Mar '19

17 Mar '19

We are happy to announce the release of Spot 2.7.2 This release contains mostly documentation improvements and some minor additions to the Python bindings. See below for a detailed list of user-visible changes. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.7.2.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.7.2 (2019-03-17) Python: - Improved support for explicit Kripke structures. It is now possible to iterate over a kripke_graph object in a way similar to twa_graph. Documentation: - A new page shows how to create explicit Kripke structures in C++ and Python. See https://spot.lrde.epita.fr/tut52.html - Another new page shows how to deal with LTLf formulas (i.e., LTL with finite semantics) and how to translate those. See https://spot.lrde.epita.fr/tut12.html Build: - Work around a spurious null dereference warning when compiling with --coverage and g++ 8.3.0-3 from Debian unstable. -- Alexandre Duret-Lutz

1 0

Spot 2.7.1 released
by Alexandre Duret-Lutz 14 Feb '19

14 Feb '19

We are happy to announce the release of Spot 2.7.1 This release contains mostly bug fixes and some minor additions to the Python bindings. See below for a detailed list of user-visible changes. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.7.1.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.7.1 (2019-02-14) Build - Work around GCC bug #89303 that causes memory leaks and std::weak_bad_ptr exceptions when Spot is compiled with the version of g++ 8.2 currently distributed by Debian unstable (starting with g++ 8.2.0-15). Python: - The following methods of spot::bdd_dict are now usable in Python when fine control over the lifetime of associations between BDD variables and atomic propositions is needed. - register_proposition(formula, for_me) - register_anonymous_variables(count, for_me) - register_all_propositions_of(other, for_me) - unregister_all_my_variables(for_me) - unregister_variable(var, for_me) - Better support for explicit Kripke structures: - the kripke_graph type now has Python bindings - spot.automaton() and spot.automata() now support a want_kripke=True to return a kripke_graph See the bottom of https://spot.lrde.epita.fr/ipynb/ltsmin-dve.html for some examples. Library: - Printing Kripke structures via print_hoa() will save state names. - kripke_graph_ptr objects now honnor any "state-names" property when formating states. Bugs fixed: - The print_dot_psl() function would incorrectly number all but the first children of commutative n-ary operators: in this case no numbering was expected. - std::out_of_range C++ exceptions raised from Python code are now converted into IndexError Python exceptions (instead of aborting the program). - The LTL parser would choke on carriage returns when command-line tools such as ltlfilt, ltlcross, or ltl2tgba were run on files of formulas with MS-DOS line endings. - The core translation for unambiguous automata was incorrectly tagging some non-weak automata as weak. - The product_susp() function used to multiply an automaton with a suspendable automaton could incorrectly build transition-based automata when multipliying two state-based automata. This caused ltl2tgba to emit error messages such as: "automaton has transition-based acceptance despite prop_state_acc()==true". -- Alexandre Duret-Lutz

1 0

Spot 2.7 released
by Alexandre Duret-Lutz 11 Dec '18

11 Dec '18

We are happy to announce the release of Spot 2.7 Someone recently reported some release-worthy bug, and unfortunately we do not have time to prepare a 2.6.4 release by cherry-picking the bug fixes from the development branch. So here is Spot 2.7 instead, with some minor new features and backward-incompatible changes done over the last 5 months. See the list below for details. This release contains contributions by Maximilien Colange, Etienne Renault, and myself. You can find the new release here: http://www.lrde.epita.fr/dload/spot/spot-2.7.tar.gz See https://spot.lrde.epita.fr/ for documentation and installation instructions. As always, please direct any feedback to <spot(a)lrde.epita.fr>. New in spot 2.7 (2018-12-11) Command-line tools: - ltlsynt now has three algorithms for synthesis: --algo=sd is the historical one. The automaton of the formula is split to separate inputs and outputs, then determinized (with Safra construction). --algo=ds the automaton of the formula is determinized (Safra), then split to separate inputs and outputs. --algo=lar translate the formula to a deterministic automaton with an arbitrary acceptance condition, then turn it into a parity automaton using LAR, and split it. In all three cases, the obtained parity game is solved using Zielonka algorithm. Calude's quasi-polynomial time algorithm has been dropped as it was not used. - ltlfilt learned --liveness to match formulas representing liveness properties. - the --stats= option of tools producing automata learned how to tell if an automaton uses universal branching (%u), or more precisely how many states (%[s]u) or edges (%[e]u) use universal branching. Python: - spot.translate() and spot.postprocess() now take an xargs= argument similar to the -x option of ltl2tgba and autfilt, making it easier to fine tune these operations. For instance ltl2tgba 'GF(a <-> XXa)' --det -x gf-guarantee=0 would be written in Python as spot.translate('GF(a <-> XXa)', 'det', xargs='gf-guarantee=0') (Note: those extra options are documented in the spot-x(7) man page.) - spot.is_generalized_rabin() and spot.is_generalized_streett() now return a tuple (b, v) where b is a Boolean, and v is the vector of the sizes of each generalized pair. This is a backward incompatible change. Library: - The LTL parser learned syntactic sugar for nested ranges of X using the X[n], F[n:m], and G[n:m] syntax of TSLF. (These correspond to the next!, next_e!, and next_a! operators of PSL, but we do not support those under these names currently.) X[6]a = XXXXXXa F[2:4]a = XX(a | X(a | Xa)) G[2:4]a = XX(a & X(a & Xa)) The corresponding constructors (for C++ and Python) are formula::X(unsigned, formula) formula::F(unsigned, unsigned, formula) formula::G(unsigned, unsigned, formula) - spot::unabbreviate(), used to rewrite away operators such as M or W, learned to use some shorter rewritings when an argument (e) is a pure eventuality or (u) is purely universal: Fe = e Gu = u f R u = u f M e = F(f & e) f W u = G(f | u) - The twa_graph class has a new dump_storage_as_dot() method to show its data structure. This is more conveniently used as aut.show_storage() in a Jupyter notebook. See https://spot.lrde.epita.fr/ipynb/twagraph-internals.html - spot::generic_emptiness_check() is a new function that performs emptiness checks of twa_graph_ptr (i.e., automata not built on-the-fly) with an *arbitrary* acceptance condition. Its sister spot::generic_emptiness_check_scc() can be used to decide the emptiness of an SCC. This is now used by twa_graph_ptr::is_empty(), twa_graph_ptr::intersects(), and scc_info::determine_unknown_acceptance(). - The new function spot::to_parity() translates an automaton with arbitrary acceptance condition into a parity automaton, based on a last-appearance record (LAR) construction. (It is used by ltlsynt but not yet by autfilt or ltl2tgba.) - The new function is_liveness() and is_liveness_automaton() can be used to check whether a formula or an automaton represents a liveness property. - Two new functions count_univbranch_states() and count_univbranch_edges() can help measuring the amount of universal branching in alternating automata. Bugs fixed: - translate() would incorrectly mark as stutter-invariant some automata produced from formulas of the form X(f...) where f... is syntactically stutter-invariant. - acc_cond::is_generalized_rabin() and acc_cond::is_generalized_streett() did not recognize the cases were a single generalized pair is used. - The pair of acc_cond::mark_t returned by acc_code::used_inf_fin_sets(), and the pair (bool, vector_rs_pairs) by acc_cond::is_rabin_like() and acc_cond::is_streett_like() were not usable in Python. - Many object types had __repr__() methods that would return the same string as __str__(), contrary to Python usage where repr(x) should try to show how to rebuild x. The following types have been changed to follow this convention: spot.acc_code spot.acc_cond spot.atomic_prop_set spot.formula spot.mark_t spot.twa_run (__repr__ shows type and address) spot.twa_word (likewise, but _repr_latex_ used in notebooks) Note that this you were relying on the fact that Jupyter calls repr() to display returned values, you may want to call print() explicitely if you prefer the old representation. - Fix compilation under Cygwin and Alpine Linux, both choking on undefined secure_getenv().

1 0