category

pairwise_strength_ranker_common

Shared preprocessing, connectivity, and MM-iteration helpers for pairwise strength rankers.

Availability:
logtalk_load(ranking_protocols(loader))
Author: Paulo Moura
Version: 1:0:0
Date: 2026-04-25
Compilation flags:
static
Uses:
avltree
list
Remarks:
(none)
Inherited public predicates:
(none)

Public predicates

(no local declarations; see entity ancestors if any)

Protected predicates

update_strengths/4

Hook predicate that importing rankers must define to perform one synchronous strength-update iteration.

Compilation flags:
static
Template:
update_strengths(Context,Strengths0,Strengths,MaximumDifference)
Mode and number of proofs:
update_strengths(+nonvar,+list(number),-list(number),-number) - one

initial_strengths/2

Initializes a positive strength vector with a uniform value for each ordered item.

Compilation flags:
static
Template:
initial_strengths(Items,Strengths)
Mode and number of proofs:
initial_strengths(+list,-list(float)) - one

strength_pairs/3

Pairs ordered items with their learned strength values.

Compilation flags:
static
Template:
strength_pairs(Items,StrengthValues,Strengths)
Mode and number of proofs:
strength_pairs(+list,+list(number),-list(pair)) - one

index_items/3

Builds Item-Index pairs for the ordered training items.

Compilation flags:
static
Template:
index_items(Items,Index,Indices)
Mode and number of proofs:
index_items(+list,+integer,-list(pair)) - one

preprocess_matchups/6

Builds directed adjacency, reverse adjacency, per-item win totals, and undirected pair-adjacency structures from aggregated pairwise matchups.

Compilation flags:
static
Template:
preprocess_matchups(Matchups,IndexDictionary,DirectedAdjacency,ReverseAdjacency,WinWeights,PairAdjacency)
Mode and number of proofs:
preprocess_matchups(+list,+compound,-compound,-compound,-compound,-compound) - one

build_dataset_model/5

Materializes dense per-item win totals and weighted undirected adjacency lists from the sparse preprocessing dictionaries.

Compilation flags:
static
Template:
build_dataset_model(Count,WinWeights,PairAdjacency,PairWeights,Wins)
Mode and number of proofs:
build_dataset_model(+integer,+compound,+compound,-list,-list(number)) - one

require_strong_connectivity/4

Checks that the directed graph is strongly connected and throws a domain error with the strongly connected components otherwise.

Compilation flags:
static
Template:
require_strong_connectivity(Count,DirectedAdjacency,ReverseAdjacency,ErrorDomain)
Mode and number of proofs:
require_strong_connectivity(+integer,+compound,+compound,+atom) - one

strongly_connected/3

True when all indexed items are mutually reachable in both the forward and reverse adjacency graphs.

Compilation flags:
static
Template:
strongly_connected(Count,DirectedAdjacency,ReverseAdjacency)
Mode and number of proofs:
strongly_connected(+integer,+compound,+compound) - zero_or_one

strongly_connected_components/4

Computes the strongly connected components of the directed graph induced by the forward and reverse adjacency dictionaries.

Compilation flags:
static
Template:
strongly_connected_components(Count,DirectedAdjacency,ReverseAdjacency,Components)
Mode and number of proofs:
strongly_connected_components(+integer,+compound,+compound,-list) - one

optimize_strengths/8

Runs the iterative strength-update loop until convergence or the maximum iteration bound is reached.

Compilation flags:
static
Template:
optimize_strengths(MaximumIterations,Tolerance,UpdateContext,Strengths0,Strengths,Status,Iterations,FinalDifference)
Mode and number of proofs:
optimize_strengths(+integer,+number,+nonvar,+list(number),-list(number),-atom,-integer,-number) - one

strength_dictionary/2

Builds an index-addressable dictionary from an ordered list of strength values.

Compilation flags:
static
Template:
strength_dictionary(Strengths,Dictionary)
Mode and number of proofs:
strength_dictionary(+list(number),-compound) - one

item_denominator/5

Accumulates the pairwise MM denominator for one item using the current strength dictionary and weighted neighbors.

Compilation flags:
static
Template:
item_denominator(Neighbors,StrengthDictionary,CurrentStrength,Denominator0,Denominator)
Mode and number of proofs:
item_denominator(+list(pair),+compound,+number,+number,-number) - one

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)