vigyasharma commented on code in PR #14729: URL: https://github.com/apache/lucene/pull/14729#discussion_r2183766249
########## lucene/core/src/java/org/apache/lucene/search/LateInteractionFloatValuesSource.java: ########## @@ -0,0 +1,194 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.lucene.search; + +import java.io.IOException; +import java.util.Arrays; +import java.util.Objects; +import org.apache.lucene.document.LateInteractionField; +import org.apache.lucene.index.BinaryDocValues; +import org.apache.lucene.index.LeafReaderContext; +import org.apache.lucene.index.VectorSimilarityFunction; + +/** + * A {@link DoubleValuesSource} that scores documents using similarity between a multi-vector query, + * and indexed document multi-vectors. + * + * <p>This is useful re-ranking query results using late interaction models, where documents and + * queries are represented as multi-vectors of composing token vectors. Document vectors are indexed + * using {@link org.apache.lucene.document.LateInteractionField}. + */ +public class LateInteractionFloatValuesSource extends DoubleValuesSource { + + private final String fieldName; + private final float[][] queryVector; + private final VectorSimilarityFunction vectorSimilarityFunction; + private final ScoreFunction scoreFunction; + + public LateInteractionFloatValuesSource(String fieldName, float[][] queryVector) { + this(fieldName, queryVector, VectorSimilarityFunction.COSINE, ScoreFunction.SUM_MAX_SIM); + } + + public LateInteractionFloatValuesSource( + String fieldName, float[][] queryVector, VectorSimilarityFunction vectorSimilarityFunction) { + this(fieldName, queryVector, vectorSimilarityFunction, ScoreFunction.SUM_MAX_SIM); + } + + public LateInteractionFloatValuesSource( + String fieldName, + float[][] queryVector, + VectorSimilarityFunction vectorSimilarityFunction, + ScoreFunction scoreFunction) { + this.fieldName = Objects.requireNonNull(fieldName); + this.queryVector = validateQueryVector(queryVector); + this.vectorSimilarityFunction = Objects.requireNonNull(vectorSimilarityFunction); + this.scoreFunction = Objects.requireNonNull(scoreFunction); + } + + private float[][] validateQueryVector(float[][] queryVector) { + if (queryVector == null || queryVector.length == 0) { + throw new IllegalArgumentException("queryVector must not be null or empty"); + } + if (queryVector[0] == null || queryVector[0].length == 0) { + throw new IllegalArgumentException( + "composing token vectors in provided query vector should not be null or empty"); + } + for (int i = 1; i < queryVector.length; i++) { + if (queryVector[i] == null || queryVector[i].length != queryVector[0].length) { + throw new IllegalArgumentException( + "all composing token vectors in provided query vector should have the same length"); + } + } + return queryVector; + } + + @Override + public DoubleValues getValues(LeafReaderContext ctx, DoubleValues scores) throws IOException { + BinaryDocValues values = ctx.reader().getBinaryDocValues(fieldName); + if (values == null) { + return DoubleValues.EMPTY; + } + + return new DoubleValues() { + @Override + public double doubleValue() throws IOException { + return scoreFunction.compare( + queryVector, + LateInteractionField.decode(values.binaryValue()), + vectorSimilarityFunction); + } + + @Override + public boolean advanceExact(int doc) throws IOException { + return values.advanceExact(doc); + } + }; + } + + @Override + public boolean needsScores() { + return false; + } + + @Override + public DoubleValuesSource rewrite(IndexSearcher reader) throws IOException { + return this; + } + + @Override + public int hashCode() { + return Objects.hash( + fieldName, Arrays.deepHashCode(queryVector), vectorSimilarityFunction, scoreFunction); + } + + @Override + public boolean equals(Object obj) { + if (this == obj) return true; + if (obj == null || getClass() != obj.getClass()) return false; + LateInteractionFloatValuesSource other = (LateInteractionFloatValuesSource) obj; + return Objects.equals(fieldName, other.fieldName) + && vectorSimilarityFunction == other.vectorSimilarityFunction + && scoreFunction == other.scoreFunction + && Arrays.deepEquals(queryVector, other.queryVector); + } + + @Override + public String toString() { + return "LateInteractionFloatValuesSource(fieldName=" + + fieldName + + " similarityFunction=" + + vectorSimilarityFunction + + " scoreFunction=" + + scoreFunction.name() + + " queryVector=" + + Arrays.deepToString(queryVector) + + ")"; + } + + @Override + public boolean isCacheable(LeafReaderContext ctx) { + return true; + } + + /** Defines the function to compute similarity score between query and document multi-vectors */ + public enum ScoreFunction { + + /** Computes the sum of max similarity between query and document vectors */ + SUM_MAX_SIM { + @Override + public float compare( + float[][] queryVector, + float[][] docVector, + VectorSimilarityFunction vectorSimilarityFunction) { + if (docVector.length == 0) { + return Float.MIN_VALUE; + } + float result = 0f; + for (float[] q : queryVector) { + float maxSim = Float.MIN_VALUE; + for (float[] d : docVector) { + if (q.length != d.length) { + throw new IllegalArgumentException( + "Provided multi-vectors are incompatible. " + + "Their composing token vectors should have the same dimension, got " Review Comment: This may get reused during graph building for multi-vector ANN, so I'm keeping it as a generic comparison between two multi-vectors. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org
