Inter language eq
Cslib.Automata.NA.Buchi.inter_language_eq
Plain-language statement
The language accepted by the intersection automaton is the intersection of the languages accepted by the two component automata.
Exact Lean statement
@[simp, scoped grind =]
theorem inter_language_eq :
language (Buchi.mk (interNA na acc) (interAccept acc)) =
⨅ i, language (Buchi.mk (na i) (acc i))Formal artifact
Lean source
@[simp, scoped grind =]theorem inter_language_eq : language (Buchi.mk (interNA na acc) (interAccept acc)) = ⨅ i, language (Buchi.mk (na i) (acc i)) := by apply mem_ext intro xs simp only [ωLanguage.mem_iInf] constructor · intro ⟨ss, h_run, h_inf⟩ i use ss.map (fun s ↦ s.fst i) constructor · apply iProd_run_iff.mp <| hist_run_proj h_run · simp only [interAccept, mem_union, frequently_or_distrib] at h_inf cases i · rcases h_inf with h_inf_f | h_inf_t · apply Frequently.mono h_inf_f grind · apply Frequently.mono <| inter_freq_acc_freq_acc h_run h_inf_t grind · rcases h_inf with h_inf_f | h_inf_t · apply Frequently.mono <| inter_freq_acc_freq_acc h_run h_inf_f grind · apply Frequently.mono h_inf_t grind · intro h choose ss_i h_ss_i using h let ss_p : ωSequence (Π i, State i) := fun k i ↦ ss_i i k have h_ss_p : (iProd na).Run xs ss_p := by grind only [Run, = iProd_run_iff, = get_fun, = LTS.OmegaExecution, = get_map] have (k : ℕ) (i : Bool) : ss_p k i = ss_i i k := rfl obtain ⟨ss, h_run, _⟩ := hist_run_exists h_ss_p use ss, h_run apply inter_freq_comp_acc_freq_acc h_run · apply Frequently.mono (h_ss_i false).2 grind · apply Frequently.mono (h_ss_i true).2 grind- Project
- Lean Computer Science Library
- License
- Apache-2.0
- Commit
- f36649cff2c9
- Source
- Cslib/Computability/Automata/NA/BuchiInter.lean:99-135
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Person-level attribution pending.
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Cslib.Automata.NA.Buchi.buchiFamily_cover
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Source project: Lean Computer Science Library
Person-level attribution pending.
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Plain-language statement
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Source project: Lean Computer Science Library
Person-level attribution pending.