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commit 87f86f82a9d8f1a78cf937fdf47a0be64086d446
parent a0505616ae96f2e4293bf8561b8a99881213d217
Author: Antoine Amarilli <a3nm@a3nm.net>
Date:   Thu, 12 Jun 2025 14:52:53 +0200

commit with codex

Diffstat:
approximate_pattern_matching | 15+++++++++++++++
bathie2021property | 15+++++++++++++++
bathie2024longest | 7+++++++
blocking_factor | 4++--
blocking_factor_minimal | 11+++++++++++
boolean_matrix_multiplication | 2+-
longest_common_extension | 4++++
longest_common_extension_wildcards | 17+++++++++++++++++
metadichotomy | 2+-
palindromic_length | 7+++++++
property_testing_formal_language | 4+++-
sparse_bmm_hypothesis | 6++++++
sparse_boolean_matrix_multiplication | 7+++++--
visibly_pushdown_automaton | 2+-
visibly_pushdown_language | 11+++++++++++
15 files changed, 106 insertions(+), 8 deletions(-)

diff --git a/approximate_pattern_matching b/approximate_pattern_matching @@ -0,0 +1,15 @@ +# Approximate pattern matching + +- find all occurrences of a pattern P in text T up to k modifications ([edit_distance]) +- only report the end of matches to avoid quadratic output + +variant: [approximate_pattern_matching_streaming] + +[academic_papers]: + +- [hazay2007approximate] +- [bathie2024longest] + +Up: [pattern_matching], [approximation] + +Aliases: pattern matching approximate diff --git a/bathie2021property b/bathie2021property @@ -0,0 +1,15 @@ +# bathie2021property + +by [gabriel] and [tatiana_starikovskaya] + +- Shows that there is a "hard" [regular_language] for which [property_testing_formal_language] requires Omega(log(1/ε)/ε) +- There are "easy" [regular_languages] needing Theta(1/ε) queries + - e.g., a^* +- There are "trivial" [regular_languages] where 0 queries are needed for large enough n + - any sufficiently long [word] cannot be [epsilon_far] from the [formal_language] + +Uses the notion of [blocking_factor]: they sample random [factors] and check if they are [blocking_factors] + +Follow-up: [bathie2025trichotomy] + +Up: [academic_paper] on [property_testing_formal_language] diff --git a/bathie2024longest b/bathie2024longest @@ -0,0 +1,7 @@ +# bathie2024longest + +- [approximate_pattern_matching] +- [LCEW] +- gives an [algorithm] for [sparse_BMM] + +Up: [academic_paper], [gabriel] diff --git a/blocking_factor b/blocking_factor @@ -2,7 +2,7 @@ A blocking factor of a [language] is a [word] which never occurs as a [factor] of a [word] of the language -- [blocking_factor_minimal] +- [minimal_blocking_factor] - [blocking_sequence] - [blocking_sequence_minimal] @@ -11,7 +11,7 @@ A blocking factor of a [language] is a [word] which never occurs as a [factor] o even for [strongly_connected] [NFA], it's [PSPACE_complete] - reduction from [NFA_universality] -See also: [links_seminar_gabriel], [property_testing] +See also: [links_seminar_gabriel], [property_testing], [Mortal_word] Aliases: blocking factors diff --git a/blocking_factor_minimal b/blocking_factor_minimal @@ -0,0 +1,11 @@ +# Blocking factor minimal + +A [blocking_factor] where no proper [factor] is a [blocking_factor] + +The set of [minimal_blocking_factors] of a [regular_language] is a [regular_language] ([bathie2025trichotomy], Lemma 3.15) + +Up: [blocking_factor] + +Aliases: minimal blocking factor, minimal blocking factors + +See also: [minimal_language] diff --git a/boolean_matrix_multiplication b/boolean_matrix_multiplication @@ -9,4 +9,4 @@ Variants: Up: [matrix_multiplication] for [boolean_semiring], [fine_grained_complexity_problems] -Aliases: matrix multiplication Boolean +Aliases: matrix multiplication Boolean, BMM diff --git a/longest_common_extension b/longest_common_extension @@ -4,6 +4,10 @@ Uses [suffix_array] Related open problem: [mirror_lce] +Generalization: [longest_common_extension_wildcards] + Up: [stringology] See also: [longest_common_subsequence] + +Aliases: LCE diff --git a/longest_common_extension_wildcards b/longest_common_extension_wildcards @@ -0,0 +1,17 @@ +# Longest common extension wildcards + +[longest_common_extension] with [wildcards] + +result by [crochemore]: [crochemore2015note] +- time O(nG) to build, with G the number of groups of wildcards +- constant time querying + +[bathie2024longest] +- allows tradeoffs +- lower bounds from [BMM] + +Can be used for [approximate_pattern_matching] + +Up: [longest_common_extension] + +Aliases: LCEW diff --git a/metadichotomy b/metadichotomy @@ -4,4 +4,4 @@ The [computational_problem] of deciding which case of a [dichotomy] result appli Up: [dichotomy] -Aliases: meta_dichotomy +Aliases: meta_dichotomy, metadichotomy criterion, metadichotomy criteria diff --git a/palindromic_length b/palindromic_length @@ -0,0 +1,7 @@ +# Palindromic length + +[computational_problem] of deciding, given a [word] w and an [integer] k, whether w is the concatenation of k [palindromes] + +[Academic_paper]: [bathie2025small] + +Up: [computational_problem] diff --git a/property_testing_formal_language b/property_testing_formal_language @@ -2,8 +2,10 @@ - [alon2001regular] on [regular_languages] - [Otilde](1/ε) bits are enough to know [with_high_probability] whether you need to change at least εn positions to belong to the target [regular_language] + - more precisely O(log^3(1/ε) / ε) - uses [hamming_distance] -- [ndione2013approximate] for [edit_distance]: +- [ndione2013approximate] for [levenshtein_distance]: + - uses the [levenshtein_distance], which is weaker - but the result is wrong according to [bathie2021property] - [bathie2021property] on [regular_languages] - uses the [levenshtein_distance], which is weaker diff --git a/sparse_bmm_hypothesis b/sparse_bmm_hypothesis @@ -0,0 +1,6 @@ +# Sparse bmm hypothesis + +[boolean_matrix_multiplication] cannot be +performed in [linear_time] in the number of 1 entries + +Up: [complexity_hypothesis], [sparse_boolean_matrix_multiplication] diff --git a/sparse_boolean_matrix_multiplication b/sparse_boolean_matrix_multiplication @@ -1,10 +1,13 @@ # Sparse BMM -[computational_hypothesis] : [boolean_matrix_multiplication] cannot be -performed in [linear_time] in the number of 1 entries +The [computational_problem] of [BMM] with [sparse_matrices] + +[computational_hypothesis]: [sparse_bmm_hypothesis] Also: [fully_sparse_boolean_matrix_multiplication] Up: [fine_grained_complexity] See also: [boolean_matrix_multiplication], [sparse] + +Aliases: sparse BMM diff --git a/visibly_pushdown_automaton b/visibly_pushdown_automaton @@ -4,6 +4,6 @@ Up: [pushdown_automaton] -See also: [tree_automaton] +See also: [tree_automaton], [visibly_pushdown_language] Aliases: VPA, VPAs, visibly pushdown automata, input driven automaton, input driven automata, input-driven automaton, input-driven automata diff --git a/visibly_pushdown_language b/visibly_pushdown_language @@ -0,0 +1,11 @@ +# Visibly pushdown language + +A [formal_language] recognized by a [visibly_pushdown_automaton] + +This is a subclass of [context_free_languages] + +Up: [formal_language] + +See also: [tree_language] + +Aliases: VPL, VPLs, visibly pushdown languages