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commit 9000341fa710c499c6a259d01742420374750e8c
parent 2f73af16ab4a6d1fb82fa898098db66df1aa4bb0
Author: Antoine Amarilli <a3nm@a3nm.net>
Date:   Tue, 18 Feb 2025 11:54:17 +0100

commit with codex

Diffstat:
automata_weighted | 2++
chase | 12++++++++++--
chase_termination | 10++++++++++
core | 21+++++++++++++++++++++
disjoint_union | 2++
equation | 2+-
graph_bipartite | 3++-
locality_logic | 8++++++++
monoid_positive | 9+++++++++
naturally_ordered_semiring | 2++
polynomial | 2+-
semiring_absorptive | 2++
12 files changed, 70 insertions(+), 5 deletions(-)

diff --git a/automata_weighted b/automata_weighted @@ -14,6 +14,8 @@ given a [word]: Schützenberger, 1961 +- [automata_weighted_conjugacy] + Up: [automata] See also: [weighted_mso] diff --git a/chase b/chase @@ -1,9 +1,17 @@ # Chase -Process for [database_dependency] to construct [universal_model] +Given [database_dependencies] and an [instance], construct a (possibly infinite) [universal_model] - [chase_termination] - [gerlach2023general]: - - cf "weakly acyclic" and other sufficient conditions for chase termination + - cf [weakly_acyclic_TGDs] and other sufficient conditions for chase termination + +Variants: + +- [chase_restricted] +- [chase_oblivious] +- [chase_core] + +Can be used for [query_optimization] Up: [database_theory] diff --git a/chase_termination b/chase_termination @@ -0,0 +1,10 @@ +# Chase termination + +depends on the kind of [chase]: +- [chase_oblivious] +- [chase_restricted] + +recent work: [hanisch2024chase] + - idea: beyond [ptime] [data_complexity] + +Up: [chase], [termination] diff --git a/core b/core @@ -0,0 +1,21 @@ +# Core + +The [core] of an [instance] A is a [subinstance] B of A such that there is no [homomorphism] from B to a strict [subinstance] B' of B +- this is unique up to [isomorphism] +- it is equal to A if there is no [endomorphism] from A to a strict [subinstance] of A + +[computational_problem] of computing the core: +- checking if a [graph] is its own core + - clearly in [coNP] (guess the [homomorphism]) + - [conp_complete] + - https://cstheory.stackexchange.com/questions/2733/what-is-the-best-exact-algorithm-to-compute-the-core-of-a-graph +- checking if input [graph] G is core of input [graph] H + - is in [dp]: + - guess existence of [homomorphism] + - guess inexistence of other [homomorphism] + - is [dp_complete] by [fagin2005data2] + - https://cstheory.stackexchange.com/questions/2733/what-is-the-best-exact-algorithm-to-compute-the-core-of-a-graph + +Up: [homomorphism] + +See also: [chase_core] diff --git a/disjoint_union b/disjoint_union @@ -3,3 +3,5 @@ The [union] of two [sets] that are [disjoint] Up: [union] + +Aliases: disjoint unions diff --git a/equation b/equation @@ -9,4 +9,4 @@ Up: [mathematics] -See also: [disequation], [inequation], [equality] +See also: [disequation], [inequation], [equality], [left_hand_side], [right_hand_side] diff --git a/graph_bipartite b/graph_bipartite @@ -1,8 +1,9 @@ # Graph bipartite -Membership can be tested in [linear_time] with [greedy_algorithm] +Testing if a [graph] is bipartite can be done in [linear_time] with [greedy_algorithm] - [deficiency] +- [complete_bipartite_graph] Up: [graph_family] diff --git a/locality_logic b/locality_logic @@ -0,0 +1,8 @@ +# Locality logic + +Works for [FO] + +- [Hanf's_theorem], cf [Hanf_normal_form] +- [Gaifman_normal_form] + +Up: [logic] diff --git a/monoid_positive b/monoid_positive @@ -0,0 +1,9 @@ +# Monoid positive + +A [monoid] being *positive* means x + y = 0 implies x = 0 and y = 0 + +aka "zero-sum-free" + +See also: [semiring_positive] + +Up: [monoid] diff --git a/naturally_ordered_semiring b/naturally_ordered_semiring @@ -3,3 +3,5 @@ [semiring] with [natural_order] Up: [natural_order], [semiring] + +Aliases: naturally ordered semirings diff --git a/polynomial b/polynomial @@ -5,6 +5,6 @@ Up: [mathematics] -See also: [polynomial_irreducible] +See also: [polynomial_irreducible], [monomial] Aliases: polynomials diff --git a/semiring_absorptive b/semiring_absorptive @@ -9,3 +9,5 @@ Implies [semiring_idempotence] Up: [dioid] See also: [absorptivity] + +Aliases: absorptive semiring, absorptive semirings